Re_training_Word2Vec_Model.ipynb

{
  "nbformat": 4,
  "nbformat_minor": 0,
  "metadata": {
    "colab": {
      "name": "Re-training Word2Vec Model.ipynb",
      "provenance": [],
      "toc_visible": true
    },
    "kernelspec": {
      "name": "python3",
      "display_name": "Python 3"
    }
  },
  "cells": [
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "BJrSMBP_Nr-F",
        "colab_type": "text"
      },
      "source": [
        "# Download Pretrained Model"
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "9gX2IUMaFRkJ",
        "colab_type": "code",
        "outputId": "77a3947a-e714-4221-cc73-89504c6e8398",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 850
        }
      },
      "source": [
        "!pip install contractions\n",
        "!pip install PyDrive"
      ],
      "execution_count": 0,
      "outputs": [
        {
          "output_type": "stream",
          "text": [
            "Requirement already satisfied: elang in /usr/local/lib/python3.6/dist-packages (0.1.1)\n",
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            "Requirement already satisfied: chardet<3.1.0,>=3.0.2 in /usr/local/lib/python3.6/dist-packages (from requests->smart-open>=1.2.1->gensim->elang) (3.0.4)\n",
            "Requirement already satisfied: urllib3<1.25,>=1.21.1 in /usr/local/lib/python3.6/dist-packages (from requests->smart-open>=1.2.1->gensim->elang) (1.24.3)\n",
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            "Requirement already satisfied: contractions in /usr/local/lib/python3.6/dist-packages (0.0.24)\n",
            "Requirement already satisfied: textsearch in /usr/local/lib/python3.6/dist-packages (from contractions) (0.0.17)\n",
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            "Requirement already satisfied: PyDrive in /usr/local/lib/python3.6/dist-packages (1.3.1)\n",
            "Requirement already satisfied: oauth2client>=4.0.0 in /usr/local/lib/python3.6/dist-packages (from PyDrive) (4.1.3)\n",
            "Requirement already satisfied: PyYAML>=3.0 in /usr/local/lib/python3.6/dist-packages (from PyDrive) (3.13)\n",
            "Requirement already satisfied: google-api-python-client>=1.2 in /usr/local/lib/python3.6/dist-packages (from PyDrive) (1.7.12)\n",
            "Requirement already satisfied: six>=1.6.1 in /usr/local/lib/python3.6/dist-packages (from oauth2client>=4.0.0->PyDrive) (1.12.0)\n",
            "Requirement already satisfied: pyasn1>=0.1.7 in /usr/local/lib/python3.6/dist-packages (from oauth2client>=4.0.0->PyDrive) (0.4.8)\n",
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            "Requirement already satisfied: httplib2>=0.9.1 in /usr/local/lib/python3.6/dist-packages (from oauth2client>=4.0.0->PyDrive) (0.17.2)\n",
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            "Requirement already satisfied: google-auth>=1.4.1 in /usr/local/lib/python3.6/dist-packages (from google-api-python-client>=1.2->PyDrive) (1.7.2)\n",
            "Requirement already satisfied: uritemplate<4dev,>=3.0.0 in /usr/local/lib/python3.6/dist-packages (from google-api-python-client>=1.2->PyDrive) (3.0.1)\n",
            "Requirement already satisfied: google-auth-httplib2>=0.0.3 in /usr/local/lib/python3.6/dist-packages (from google-api-python-client>=1.2->PyDrive) (0.0.3)\n",
            "Requirement already satisfied: cachetools<3.2,>=2.0.0 in /usr/local/lib/python3.6/dist-packages (from google-auth>=1.4.1->google-api-python-client>=1.2->PyDrive) (3.1.1)\n",
            "Requirement already satisfied: setuptools>=40.3.0 in /usr/local/lib/python3.6/dist-packages (from google-auth>=1.4.1->google-api-python-client>=1.2->PyDrive) (46.1.3)\n"
          ],
          "name": "stdout"
        }
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "FUrEmBdgFdl3",
        "colab_type": "code",
        "colab": {}
      },
      "source": [
        "from pydrive.auth import GoogleAuth\n",
        "from pydrive.drive import GoogleDrive\n",
        "from google.colab import auth\n",
        "from oauth2client.client import GoogleCredentials\n",
        "\n",
        "auth.authenticate_user()\n",
        "gauth = GoogleAuth()\n",
        "gauth.credentials = GoogleCredentials.get_application_default()\n",
        "drive = GoogleDrive(gauth)"
      ],
      "execution_count": 0,
      "outputs": []
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "TntlmYX-FfiM",
        "colab_type": "code",
        "outputId": "05e3b67d-4649-4982-874b-c0d6d99133f8",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 628
        }
      },
      "source": [
        "# download pre-trained model\n",
        "# you can replace the id with id of file you want to access\n",
        "model_id = \"1vXsf0DI8HKGuqYFIGIrvG-73KzZPgz5h\"\n",
        "downloaded = drive.CreateFile({'id':model_id})\n",
        "downloaded.GetContentFile('wiki_Animal.model')"
      ],
      "execution_count": 0,
      "outputs": [
        {
          "output_type": "stream",
          "text": [
            "2020-04-23 13:42:47,596 : WARNING : file_cache is unavailable when using oauth2client >= 4.0.0 or google-auth\n",
            "Traceback (most recent call last):\n",
            "  File \"/usr/local/lib/python3.6/dist-packages/googleapiclient/discovery_cache/__init__.py\", line 36, in autodetect\n",
            "    from google.appengine.api import memcache\n",
            "ModuleNotFoundError: No module named 'google.appengine'\n",
            "\n",
            "During handling of the above exception, another exception occurred:\n",
            "\n",
            "Traceback (most recent call last):\n",
            "  File \"/usr/local/lib/python3.6/dist-packages/googleapiclient/discovery_cache/file_cache.py\", line 33, in <module>\n",
            "    from oauth2client.contrib.locked_file import LockedFile\n",
            "ModuleNotFoundError: No module named 'oauth2client.contrib.locked_file'\n",
            "\n",
            "During handling of the above exception, another exception occurred:\n",
            "\n",
            "Traceback (most recent call last):\n",
            "  File \"/usr/local/lib/python3.6/dist-packages/googleapiclient/discovery_cache/file_cache.py\", line 37, in <module>\n",
            "    from oauth2client.locked_file import LockedFile\n",
            "ModuleNotFoundError: No module named 'oauth2client.locked_file'\n",
            "\n",
            "During handling of the above exception, another exception occurred:\n",
            "\n",
            "Traceback (most recent call last):\n",
            "  File \"/usr/local/lib/python3.6/dist-packages/googleapiclient/discovery_cache/__init__.py\", line 42, in autodetect\n",
            "    from . import file_cache\n",
            "  File \"/usr/local/lib/python3.6/dist-packages/googleapiclient/discovery_cache/file_cache.py\", line 41, in <module>\n",
            "    \"file_cache is unavailable when using oauth2client >= 4.0.0 or google-auth\"\n",
            "ImportError: file_cache is unavailable when using oauth2client >= 4.0.0 or google-auth\n",
            "2020-04-23 13:42:47,598 : INFO : URL being requested: GET https://www.googleapis.com/discovery/v1/apis/drive/v2/rest\n",
            "2020-04-23 13:42:47,599 : INFO : Attempting refresh to obtain initial access_token\n",
            "2020-04-23 13:42:47,601 : INFO : Refreshing access_token\n",
            "2020-04-23 13:42:47,742 : INFO : URL being requested: GET https://www.googleapis.com/drive/v2/files/1vXsf0DI8HKGuqYFIGIrvG-73KzZPgz5h?alt=json\n"
          ],
          "name": "stderr"
        }
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "9wXpWcxkN0fQ",
        "colab_type": "text"
      },
      "source": [
        "# Provide Callback"
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "Qd8EYRmAGBQ3",
        "colab_type": "code",
        "colab": {}
      },
      "source": [
        "from time import time\n",
        "\n",
        "import logging\n",
        "logging.basicConfig(format='%(asctime)s : %(levelname)s : %(message)s', level=logging.INFO)\n",
        "\n",
        "from gensim.models.callbacks import CallbackAny2Vec\n",
        "class Callback(CallbackAny2Vec):\n",
        "    def __init__(self):\n",
        "        self.epoch = 1\n",
        "\n",
        "    def on_epoch_end(self, model):\n",
        "        loss = model.get_latest_training_loss()\n",
        "        if self.epoch == 1:\n",
        "            print('Loss after epoch {}: {}'.format(self.epoch, loss))\n",
        "        else:\n",
        "            print('Loss after epoch {}: {}'.format(self.epoch, loss - self.loss_previous_step))\n",
        "        self.epoch += 1\n",
        "        self.loss_previous_step = loss"
      ],
      "execution_count": 0,
      "outputs": []
    },
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "tC24AgJlN2aK",
        "colab_type": "text"
      },
      "source": [
        "# Load Pretrained Model"
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "6NbBiV11FxcZ",
        "colab_type": "code",
        "outputId": "8b20d022-fead-4891-cb61-a9a2c5e81f99",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 222
        }
      },
      "source": [
        "from gensim.models import Word2Vec\n",
        "model = Word2Vec.load(\"wiki_Animal.model\")\n",
        "print(model)"
      ],
      "execution_count": 0,
      "outputs": [
        {
          "output_type": "stream",
          "text": [
            "2020-04-23 14:10:42,791 : INFO : loading Word2Vec object from wiki_Animal.model\n",
            "/usr/local/lib/python3.6/dist-packages/smart_open/smart_open_lib.py:253: UserWarning: This function is deprecated, use smart_open.open instead. See the migration notes for details: https://github.com/RaRe-Technologies/smart_open/blob/master/README.rst#migrating-to-the-new-open-function\n",
            "  'See the migration notes for details: %s' % _MIGRATION_NOTES_URL\n",
            "2020-04-23 14:10:43,313 : INFO : loading wv recursively from wiki_Animal.model.wv.* with mmap=None\n",
            "2020-04-23 14:10:43,314 : INFO : setting ignored attribute vectors_norm to None\n",
            "2020-04-23 14:10:43,318 : INFO : loading vocabulary recursively from wiki_Animal.model.vocabulary.* with mmap=None\n",
            "2020-04-23 14:10:43,322 : INFO : loading trainables recursively from wiki_Animal.model.trainables.* with mmap=None\n",
            "2020-04-23 14:10:43,323 : INFO : setting ignored attribute cum_table to None\n",
            "2020-04-23 14:10:43,324 : INFO : loaded wiki_Animal.model\n"
          ],
          "name": "stderr"
        },
        {
          "output_type": "stream",
          "text": [
            "Word2Vec(vocab=23190, size=300, alpha=0.005)\n"
          ],
          "name": "stdout"
        }
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "XMlxJ9iPYCyb",
        "colab_type": "code",
        "colab": {}
      },
      "source": [
        "old_vocab = list(model.wv.vocab)"
      ],
      "execution_count": 0,
      "outputs": []
    },
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "f6ru6cbtUMYf",
        "colab_type": "text"
      },
      "source": [
        "# Gather and Preprocess New Data"
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "dneNHgO-Rxjn",
        "colab_type": "code",
        "outputId": "86bcaa1b-99ba-4b1b-8071-32ee31e492ba",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 92
        }
      },
      "source": [
        "from elang.word2vec.builder import build_from_wikipedia\n",
        "build_from_wikipedia(\n",
        "    slug = \"Cuteness\", # scrape with query\n",
        "    levels = 1, # levels of articles\n",
        "    lang = \"en\", # english language\n",
        "    model = False, # don't create model\n",
        "    save = True) # save to txt file"
      ],
      "execution_count": 0,
      "outputs": [
        {
          "output_type": "stream",
          "text": [
            "Level 1 Queried so far: ['Cranium', 'Anteroposterior', 'Tardigrades', 'Birth_control_pill', 'London_University', 'Sweet_Lolita', 'Cuteness', 'Supraorbital_ridge', 'Human_development_(biology)', 'Socially_accepted', 'Heart_(symbol)', 'Domestication_of_dogs'] \n",
            "\n",
            "Article content successfully saved to wikipedia_branch_Cuteness_1.txt\n"
          ],
          "name": "stdout"
        }
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "VX8wsRLPT0cF",
        "colab_type": "code",
        "outputId": "3b20fbc5-1069-4103-c082-97bc9e302d44",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 129
        }
      },
      "source": [
        "wiki_file = open(\"/content/corpus/txt/wikipedia_branch_Cuteness_1.txt\", \"r\")\n",
        "wiki_text = wiki_file.readlines()\n",
        "wiki_text[:5]"
      ],
      "execution_count": 0,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "['  The skull is a bony structure that forms the head in vertebrates. It supports the structures of the face and provides a protective cavity for the brain.[1] The skull is composed of two parts: the cranium and the mandible. In humans, these two parts are the neurocranium and the viscerocranium or facial skeleton that includes the mandible as its largest bone. The skull forms the anterior most portion of the skeleton and is a product of cephalisation—housing the brain, and several sensory structures such as the eyes, ears, nose, and mouth.[2] In humans these sensory structures are part of the facial skeleton.  Functions of the skull include protection of the brain, fixing the distance between the eyes to allow stereoscopic vision, and fixing the position of the ears to enable sound localisation of the direction and distance of sounds. In some animals such as horned ungulates, the skull also has a defensive function by providing the mount (on the frontal bone) for the horns.  The English word \"skull\" is probably derived from Old Norse \"skulle\", while the Latin word cranium comes from the Greek root κρανίον (kranion).  The skull is made up of a number of fused flat bones, and contains many foramina, fossae, processes, and several cavities or sinuses. In zoology there are openings in the skull called fenestrae.  The human skull is the bony structure that forms the head in the human skeleton. It supports the structures of the face and forms a cavity for the brain. Like the skulls of other vertebrates, it protects the brain from injury.[3]  The skull consists of three parts, of different embryological origin—the neurocranium, the sutures, and the facial skeleton (also called the membraneous viscerocranium). The neurocranium (or braincase) forms the protective cranial cavity that surrounds and houses the brain and brainstem.[4] The upper areas of the cranial bones form the calvaria (skullcap). The membranous viscerocranium includes the mandible.  The sutures are fairly rigid joints between bones of the neurocranium.  The facial skeleton is formed by the bones supporting the face.  Except for the mandible, all of the bones of the skull are joined together by sutures—synarthrodial (immovable) joints formed by bony ossification, with Sharpey\\'s fibres permitting some flexibility. Sometimes there can be extra bone pieces within the suture known as wormian bones or sutural bones. Most commonly these are found in the course of the lambdoid suture.  The human skull is generally considered to consist of twenty-two bones—eight cranial bones and fourteen facial skeleton bones. In the neurocranium these are the occipital bone, two temporal bones, two parietal bones, the sphenoid, ethmoid and frontal bones.  The bones of the facial skeleton (14) are the vomer, two inferior nasal conchae, two nasal bones, two maxilla, the mandible, two palatine bones, two zygomatic bones, and two lacrimal bones. Some sources count a paired bone as one, or the maxilla as having two bones (as its parts); some sources include the hyoid bone or the three ossicles of the middle ear but the overall general consensus of the number of bones in the human skull is the stated twenty-two.  Some of these bones—the occipital, parietal, frontal, in the neurocranium, and the nasal, lacrimal, and vomer, in the facial skeleton are flat bones.  The skull also contains sinuses, air-filled cavities known as paranasal sinuses, and numerous foramina. The sinuses are lined with respiratory epithelium. Their known functions are the lessening of the weight of the skull, the aiding of resonance to the voice and the warming and moistening of the air drawn into the nasal cavity.  The foramina are openings in the skull. The largest of these is the foramen magnum that allows the passage of the spinal cord as well as nerves and blood vessels.  The many processes of the skull include the mastoid process and the zygomatic processes.  The skull is a complex structure; its bones are formed both by intramembranous and endochondral ossification. The skull roof bones, comprising the bones of the facial skeleton and the sides and roof of the neurocranium, are dermal bones formed by intramembranous ossification, though the temporal bones are formed by endochondral ossification. The endocranium, the bones supporting the brain (the occipital, sphenoid, and ethmoid) are largely formed by endochondral ossification. Thus frontal and parietal bones are purely membranous.[5] The geometry of the skull base and its fossae, the anterior, middle and posterior cranial fossae changes rapidly. The anterior cranial fossa changes especially during the first trimester of pregnancy and skull defects can often develop during this time.[6]  At birth, the human skull is made up of 44 separate bony elements. During development, many of these bony elements gradually fuse together into solid bone (for example, the frontal bone). The bones of the roof of the skull are initially separated by regions of dense connective tissue called fontanelles. There are six fontanelles: one anterior (or frontal), one posterior (or occipital), two sphenoid (or anterolateral), and two mastoid (or posterolateral). At birth these regions are fibrous and moveable, necessary for birth and later growth. This growth can put a large amount of tension on the \"obstetrical hinge\", which is where the squamous and lateral parts of the occipital bone meet. A possible complication of this tension is rupture of the great cerebral vein. As growth and ossification progress, the connective tissue of the fontanelles is invaded and replaced by bone creating sutures. The five sutures are the two squamous sutures, one coronal, one lambdoid, and one sagittal suture. The posterior fontanelle usually closes by eight weeks, but the anterior fontanel can remain open up to eighteen months. The anterior fontanelle is located at the junction of the frontal and parietal bones; it is a \"soft spot\" on a baby\\'s forehead. Careful observation will show that you can count a baby\\'s heart rate by observing the pulse pulsing softly through the anterior fontanelle.  The skull in the neonate is large in proportion to other parts of the body. The facial skeleton is one seventh of the size of the calvaria. (In the adult it is half the size). The base of the skull is short and narrow, though the inner ear is almost adult size.[7]  Craniosynostosis is a condition in which one or more of the fibrous sutures in an infant skull prematurely fuses,[8] and changes the growth pattern of the skull.[9] Because the skull cannot expand perpendicular to the fused suture, it grows more in the parallel direction.[9] Sometimes the resulting growth pattern provides the necessary space for the growing brain, but results in an abnormal head shape and abnormal facial features.[9] In cases in which the compensation does not effectively provide enough space for the growing brain, craniosynostosis results in increased intracranial pressure leading possibly to visual impairment, sleeping impairment, eating difficulties, or an impairment of mental development.[10]  A copper beaten skull is a phenomenon wherein intense intracranial pressure disfigures the internal surface of the skull.[11] The name comes from the fact that the inner skull has the appearance of having been beaten with a ball-peen hammer, such as is often used by coppersmiths. The condition is most common in children.  Injuries to the brain can be life-threatening. Normally the skull protects the brain from damage through its hard unyieldingness; the skull is one of the least deformable structures found in nature with it needing the force of about 1 ton to reduce the diameter of the skull by 1 cm.[12] In some cases, however, of head injury, there can be raised intracranial pressure through mechanisms such as a subdural haematoma. In these cases the raised intracranial pressure can cause herniation of the brain out of the foramen magnum (\"coning\") because there is no space for the brain to expand; this can result in significant brain damage or death unless an urgent operation is performed to relieve the pressure. This is why patients with concussion must be watched extremely carefully.  Dating back to Neolithic times, a skull operation called trepanning was sometimes performed. This involved drilling a burr hole in the cranium. Examination of skulls from this period reveals that the patients sometimes survived for many years afterward. It seems likely that trepanning was also performed purely for ritualistic or religious reasons. Nowadays this procedure is still used but is normally called a craniectomy.  In March 2013, for the first time in the U.S., researchers replaced a large percentage of a patient\\'s skull with a precision, 3D-printed polymer implant.[13] About 9 months later, the first complete cranium replacement with a 3D-printed plastic insert was performed on a Dutch woman. She had been suffering from hyperostosis, which increased the thickness of her skull and compressed her brain.[14]  A study conducted in 2018 by the researchers of Harvard Medical School in Boston, funded by National Institutes of Health (NIH) suggested that instead of travelling via blood, there are \"tiny channels\" in the skull through which the immune cells combined with the bone marrow reach the areas of inflammation after an injury to the brain tissues.[15]  Surgical alteration of sexually dimorphic skull features may be carried out as a part of facial feminization surgery, a set of reconstructive surgical procedures that can alter male facial features to bring them closer in shape and size to typical female facial features.[16][17] These procedures can be an important part of the treatment of transgender people for gender dysphoria.[18][19]  Artificial cranial deformation is a largely historical practice of some cultures. Cords and wooden boards would be used to apply pressure to an infant\\'s skull and alter its shape, sometimes quite significantly. This procedure would begin just after birth and would be carried on for several years.[citation needed]  Like the face, the skull and teeth can also indicate a person\\'s life history and origin. Forensic scientists and archaeologists use metric and nonmetric traits to estimate what the bearer of the skull looked like. When a significant amount of bones are found, such as at Spitalfields in the UK and Jōmon shell mounds in Japan, osteologists can use traits, such as the proportions of length, height and width, to know the relationships of the population of the study with other living or extinct populations.[citation needed]  The German physician Franz Joseph Gall in around 1800 formulated the theory of phrenology, which attempted to show that specific features of the skull are associated with certain personality traits or intellectual capabilities of its owner. His theory is now considered to be pseudoscientific.[citation needed]  In the mid-nineteenth century, anthropologists found it crucial to distinguish between male and female skulls. An anthropologist of the time, James McGrigor Allan, argued that the female brain was similar to that of an animal.[20] This allowed anthropologists to declare that women were in fact more emotional and less rational than men. McGrigor then concluded that women\\'s brains were more analogous to infants, thus deeming them inferior at the time.[20] To further these claims of female inferiority and silence the feminists of the time, other anthropologists joined in on the studies of the female skull. These cranial measurements are the basis of what is known as craniology. These cranial measurements were also used to draw a connection between women and black people.[20]  Research has shown that while in early life there is little difference between male and female skulls, in adulthood male skulls tend to be larger and more robust than female skulls, which are lighter and smaller, with a cranial capacity about 10 percent less than that of the male.[21] However, later studies show that women\\'s skulls are slightly thicker and thus men may be more susceptible to head injury than women.[22][23]  Male skulls can have more prominent supraorbital ridges, a more prominent glabella, and more prominent temporal lines. Female skulls generally have rounder orbits, and narrower jaws. Male skulls on average have larger, broader palates, squarer orbits, larger mastoid processes, larger sinuses, and larger occipital condyles than those of females. Male mandibles typically have squarer chins and thicker, rougher muscle attachments than female mandibles.[citation needed]  The cephalic index is the ratio of the width of the head, multiplied by 100 and divided by its length (front to back). The index is also used to categorize animals, especially dogs and cats. The width is usually measured just below the parietal eminence, and the length from the glabella to the occipital point.  Humans may be:  Dolichocephalic — long-headed Mesaticephalic — medium-headed Brachycephalic — short-headed[7] The skull of fishes is formed from a series of only loosely connected bones. Lampreys and sharks only possess a cartilaginous endocranium, with both the upper and lower jaws being separate elements. Bony fishes have additional dermal bone, forming a more or less coherent skull roof in lungfish and holost fish. The lower jaw defines a chin.  The simpler structure is found in jawless fish, in which the cranium is normally represented by a trough-like basket of cartilaginous elements only partially enclosing the brain, and associated with the capsules for the inner ears and the single nostril. Distinctively, these fish have no jaws.[24]  Cartilaginous fish, such as sharks and rays, have also simple, and presumably primitive, skull structures. The cranium is a single structure forming a case around the brain, enclosing the lower surface and the sides, but always at least partially open at the top as a large fontanelle. The most anterior part of the cranium includes a forward plate of cartilage, the rostrum, and capsules to enclose the olfactory organs. Behind these are the orbits, and then an additional pair of capsules enclosing the structure of the inner ear. Finally, the skull tapers towards the rear, where the foramen magnum lies immediately above a single condyle, articulating with the first vertebra. There are, in addition, at various points throughout the cranium, smaller foramina for the cranial nerves. The jaws consist of separate hoops of cartilage, almost always distinct from the cranium proper.[24]  In ray-finned fish, there has also been considerable modification from the primitive pattern. The roof of the skull is generally well formed, and although the exact relationship of its bones to those of tetrapods is unclear, they are usually given similar names for convenience. Other elements of the skull, however, may be reduced; there is little cheek region behind the enlarged orbits, and little, if any bone in between them. The upper jaw is often formed largely from the premaxilla, with the maxilla itself located further back, and an additional bone, the symplectic, linking the jaw to the rest of the cranium.[25]  Although the skulls of fossil lobe-finned fish resemble those of the early tetrapods, the same cannot be said of those of the living lungfishes. The skull roof is not fully formed, and consists of multiple, somewhat irregularly shaped bones with no direct relationship to those of tetrapods. The upper jaw is formed from the pterygoids and vomers alone, all of which bear teeth. Much of the skull is formed from cartilage, and its overall structure is reduced.[25]  The skulls of the earliest tetrapods closely resembled those of their ancestors amongst the lobe-finned fishes. The skull roof is formed of a series of plate-like bones, including the maxilla, frontals, parietals, and lacrimals, among others. It is overlaying the endocranium, corresponding to the cartilaginous skull in sharks and rays. The various separate bones that compose the temporal bone of humans are also part of the skull roof series. A further plate composed of four pairs of bones forms the roof of the mouth; these include the vomer and palatine bones. The base of the cranium is formed from a ring of bones surrounding the foramen magnum and a median bone lying further forward; these are homologous with the occipital bone and parts of the sphenoid in mammals. Finally, the lower jaw is composed of multiple bones, only the most anterior of which (the dentary) is homologous with the mammalian mandible.[25]  In living tetrapods, a great many of the original bones have either disappeared or fused into one another in various arrangements.  Birds have a diapsid skull, as in reptiles, with a prelachrymal fossa (present in some reptiles). The skull has a single occipital condyle.[26] The skull consists of five major bones: the frontal (top of head), parietal (back of head), premaxillary and nasal (top beak), and the mandible (bottom beak). The skull of a normal bird usually weighs about 1% of the bird\\'s total bodyweight. The eye occupies a considerable amount of the skull and is surrounded by a sclerotic eye-ring, a ring of tiny bones. This characteristic is also seen in reptiles.  Living amphibians typically have greatly reduced skulls, with many of the bones either absent or wholly or partly replaced by cartilage.[25] In mammals and birds, in particular, modifications of the skull occurred to allow for the expansion of the brain. The fusion between the various bones is especially notable in birds, in which the individual structures may be difficult to identify.  The temporal fenestrae are anatomical features of the skulls of several types of amniotes, characterised by bilaterally symmetrical holes (fenestrae) in the temporal bone. Depending on the lineage of a given animal, two, one, or no pairs of temporal fenestrae may be present, above or below the postorbital and squamosal bones. The upper temporal fenestrae are also known as the supratemporal fenestrae, and the lower temporal fenestrae are also known as the infratemporal fenestrae. The presence and morphology of the temporal fenestra are critical for taxonomic classification of the synapsids, of which mammals are part.  Physiological speculation associates it with a rise in metabolic rates and an increase in jaw musculature. The earlier amniotes of the Carboniferous did not have temporal fenestrae but two more advanced lines did: the synapsids (mammal-like reptiles) and the diapsids (most reptiles and later birds). As time progressed, diapsids\\' and synapsids\\' temporal fenestrae became more modified and larger to make stronger bites and more jaw muscles. Dinosaurs, which are diapsids, have large advanced openings, and their descendants, the birds, have temporal fenestrae which have been modified. Mammals, which are synapsids, possess one fenestral opening in the skull, situated to the rear of the orbit.  There are four types of amniote skull, classified by the number and location of their temporal fenestrae. These are:  Anapsida – no openings Synapsida – one low opening (beneath the postorbital and squamosal bones) Euryapsida – one high opening (above the postorbital and squamosal bones); euryapsids actually evolved from a diapsid configuration, losing their lower temporal fenestra. Diapsida – two openings Evolutionarily, they are related as follows:  Amniota Class Synapsida Order Therapsida Class Mammalia – mammals (Unranked) Sauropsida – reptiles and birds Class Reptilia Subclass Parareptilia Infraclass Anapsida Subclass Eureptilia Infraclass Diapsida Class Aves Infraclass Euryapsida Class Synapsida Order Therapsida Class Mammalia – mammals Order Therapsida Class Mammalia – mammals Class Mammalia – mammals (Unranked) Sauropsida – reptiles and birds Class Reptilia Subclass Parareptilia Infraclass Anapsida Subclass Eureptilia Infraclass Diapsida Class Aves Infraclass Euryapsida Class Reptilia Subclass Parareptilia Infraclass Anapsida Subclass Eureptilia Infraclass Diapsida Class Aves Infraclass Euryapsida Subclass Parareptilia Infraclass Anapsida Infraclass Anapsida Subclass Eureptilia Infraclass Diapsida Class Aves Infraclass Euryapsida Infraclass Diapsida Class Aves Class Aves Infraclass Euryapsida The jugal is a skull bone found in most reptiles, amphibians, and birds. In mammals, the jugal is often called the zygomatic bone or malar bone.  The prefrontal bone is a bone separating the lacrimal and frontal bones in many tetrapod skulls.  Chondrocranium, a primitive cartilagionous skeletal structure Endocranium Epicranium Pericranium, a membrane that lines the outer surface of the cranium   This article incorporates text in the public domain from page 128 of the 20th edition of Gray\\'s Anatomy (1918)  Skull Module (California State University Department of Anthology) Skull Anatomy Tutorial. (GateWay Community College) Bird Skull Collection Bird skull database with very large collection of skulls (Agricultural University of Wageningen) Human skull base (in German) Human Skulls / Anthropological Skulls / Comparison of Skulls of Vertebrates (PDF; 502 kB)\\n',\n",
              " 'Standard anatomical terms of location deal unambiguously with the anatomy of animals, including humans.  All vertebrates (including humans) have the same basic body plan: they are strictly bilaterally symmetrical in early embryonic stages and largely bilaterally symmetrical in adulthood.[1] If they are divided down the middle, in other words, they have mirror-image left and right halves.[2] For those reasons, the basic directional terms can be considered to be those used in vertebrates. By extension, the same terms are used for many other (invertebrate) organisms.  While the terms are standardized within specific fields of biology, there are unavoidable, sometimes dramatic, differences between some disciplines. For example, differences in terminology remain a problem that to some extent still separates the terminology of human anatomy from the one that is used in the study of various other zoological categories.  Standardized anatomical and zoological terms of location have been developed, usually based on Latin and Greek words, to enable all biological and medical scientists to precisely delineate and communicate information about animal bodies and their component organs, even though the meaning of some of the terms often is context-sensitive.[3]  The vertebrates and Craniata share a substantial heritage and common structure, so many of the same terms are used for location. To avoid ambiguities this terminology is based on the anatomy of each animal in a standard way.  For humans, one type of vertebrate, anatomical terms may differ from other forms of vertebrates. One reason is that humans have a different neuraxis and another is that unlike animals that rest on four limbs, humans are considered when describing anatomy as being in the standard anatomical position. Thus, what is on \"top\" of a human is the head, whereas the \"top\" of a dog may be its back, and the \"top\" of a flounder could refer to either its left or its right side.  For invertebrates, standard application of locational terminology often becomes difficult or debatable at best when the differences in morphology are so radical that common concepts are not homologous and do not refer to common concepts. For example, many species are not even bilaterally symmetrical. In those species, terminology depends on their type of symmetry, if they have any.  Because animals can change orientation with respect to their environment, and because appendages like limbs and tentacles can change position with respect to the main body, positional descriptive terms need to refer to the animal as in its standard anatomical position. All descriptions are with respect to the organism in its standard anatomical position, even when the organism in question has appendages in another position. This helps avoid confusion in terminology when referring to the same organism in different postures.  In humans, this refers to the body in a standing position with arms at the side and palms facing forward (thumbs out and to the sides). While the universal vertebrate terminology used in veterinary medicine would work in human medicine, the human terms are thought to be too well established to be worth changing.  Many anatomical terms can be combined, either to indicate a position in two axes simultaneously or to indicate the direction of a movement relative to the body. For example, \"anterolateral\" indicates a position that is both anterior and lateral to the body axis (such as the bulk of the pectoralis major muscle). In radiology, an X-ray image may be said to be \"anteroposterior\", indicating that the beam of X-rays pass from their source to patient\\'s anterior body wall through the body to exit through posterior body wall.[4]  There is no definite limit to the contexts in which terms may be modified to qualify each other in such combinations. Generally the modifier term is truncated and an \"o\" or an \"i\" is added in prefixing it to the qualified term. For example, a view of an animal from an aspect at once dorsal and lateral might be called a \"dorsolateral\" view; and the effect of dorsolateral flattening in an organism such as a krait gives its body a triangular cross section. Again, in describing the morphology of an organ or habitus of an animal such as many of the Platyhelminthes, one might speak of it as \"dorsiventrally\" flattened as opposed to bilaterally flattened animals such as ocean sunfish.  Where desirable three or more terms may be agglutinated or concatenated, as in \"anteriodorsolateral\". Such terms sometimes used to be hyphenated, but the modern tendency is to omit the hyphen. There is however little basis for any strict rule to interfere with choice of convenience in such usage.[5]  A transverse plane, also known as a cross-section, divides the body into cranial and caudal (head and tail) portions. A longitudinal plane is any plane that is perpendicular to the transverse plane.[6] The main longitudinal planes are: The frontal plane or coronal plane divides the body into dorsal and ventral (back and front, or posterior and anterior) portions. For post-embryonic humans a coronal plane is vertical and a transverse plane is horizontal, but for embryos and quadrupeds a coronal plane is horizontal and a transverse plane is vertical. The sagittal plane is a plane parallel to the sagittal suture. All other sagittal planes (referred to as parasagittal planes) are parallel to it. The plane is a Y-Z plane, perpendicular to the ground. A radial plane is any one of the cross sections that run through a cylindrical shaped portion of the body that are coincident with radii that run from a central point. The midsagittal and midcoronal planes would both be examples of radial planes, but so would all other planes that cross the intersection of these two planes. A special sagittal plane is the median plane or midsagittal plane in the midline of the body, and divides the body into left and right (sinister and dexter) portions.[7] This passes through the head, spinal cord, navel, and, in many animals, the tail.[7] The term \"median plane\" can also refer to the midsagittal plane of other structures, such as a digit.  In human anatomy:  A transverse (also known as horizontal) plane is an X-Z plane, parallel to the ground, which (in humans) separates the superior from the inferior or, put another way, the head from the feet. A coronal (also known as frontal) plane is a X-Y plane, perpendicular to the ground, which (in humans) separates the anterior from the posterior, the front from the back, the ventral from the dorsal. To begin with, distinct, polar-opposite ends of the organism are chosen. By definition, each pair of opposite points defines an axis. In a bilaterally symmetrical organism, there are 6 polar opposite points, giving three axes that intersect at right angles – the x, y, and z axes familiar from three-dimensional geometry.  The terms \"intermediate\", \"ipsilateral\", \"contralateral\", \"superficial\", and \"deep\", while indicating directions, are relative terms and thus do not properly define fixed anatomical axes. Also, while the \"rostrocaudal\" and anteroposterior directionality are equivalent in a significant portion of the human body, they are different directions in other parts of the body.     In anatomical terminology superior (from Latin, meaning \\'above\\') is used to refer to what is above something, and inferior (from Latin, meaning \\'below\\') to what is below it. For example, in the anatomical position the most superior part of the human body is the head, and the most inferior is the feet.[9][10] As a second example, in humans the neck is superior to the chest but inferior to the head.  Anterior refers to what is in front (from Latin ante, meaning \"before\") and posterior, what is to the back of the subject (from Latin post, meaning \"after\").[11] For example, in a dog the nose is anterior to the eyes and the tail is considered the most posterior part; in many fish the gill openings are posterior to the eyes, but anterior to the tail. In projectional radiography terminology, an anteroposterior (AP) projection is taken with the X-ray generator anteriorly (such as in the front of a human), and the X-ray detector posteriorly. In contrast, a posteroanterior (PA) projection is taken with the X-ray generator posteriorly.   Lateral (from Latin lateralis, meaning \\'to the side\\') refers to the sides of an animal, as in \"left lateral\" and \"right lateral\". The term medial (from Latin medius, meaning \\'middle\\') is used to refer to structures close to the centre of an organism, called the \"median plane\".[2] For example, in a human, imagine a line down the center of the body from the head through the navel and going between the legs— the medial side of the foot would be the big toe side; the medial side of the knee would be the side adjacent to the other knee. To describe the sides of the knees touching each other would be \"right medial\" and \"left medial\".  The terms \"left\" and \"right\" are sometimes used, or their Latin alternatives (Latin: dexter; \"right\", Latin: sinister; \"left\"). However, as left and right sides are mirror images, using these words is somewhat confusing, as structures are duplicated on both sides. For example, it is very confusing to say the dorsal fin of a dolphin is \"right of\" the left pectoral fin, but is \"left of\" the right eye, but much easier and clearer to say \"the dorsal fin is medial to the pectoral fins\".  Terms derived from lateral include:  Contralateral (from Latin contra, meaning \\'against\\'): on the side opposite to another structure. For example, the right arm and leg are represented by the left, i.e., contralateral side of the forebrain. Ipsilateral (from Latin ipse, meaning \\'same\\'): on the same side as another structure. For example, the left arm is ipsilateral to the left leg. Bilateral (from Latin bis, meaning \\'twice\\'): on both sides of the body. For example, bilateral orchiectomy (removal of testes on both sides of the body\\'s axis) is surgical castration. Unilateral (from Latin unus, meaning \\'one\\'): on one side of the body. For example, unilateral paresis is hemiparesis. Terms derived from medial include:  Inferomedial (from Latin inferus, meaning \\'lower\\'): lower and in or near the midline. For example, the human nose is inferomedial to the eyes. Superomedial (from Latin superus, meaning \\'above\\'): above and toward the midline. For example, the human nose is superomedial to the mouth. Varus and valgus correspond to medial and lateral, respectively, regarding the distal segment\\'s vector relative to the proximal segment\\'s vector.    The terms proximal (from Latin proximus, meaning \\'nearest\\') and distal (from Latin distare, meaning \\'to stand away from\\') are used to describe parts of a feature that are close to or distant from the main mass of the body, respectively.[11] Thus the upper arm in humans is proximal and the hand is distal.  These terms are frequently used when describing appendages such as fins, tentacles, limbs or any structure that extends that can potentially move separately from the main body. Although the direction indicated by \"proximal\" and \"distal\" is always respectively towards or away from the point of attachment, a given structure can be either proximal or distal in relation to another point of reference. Thus the elbow is distal to a wound on the upper arm, but proximal to a wound on the lower arm.[12]  This terminology is also employed in molecular biology and therefore by extension is also used in chemistry, specifically referring to the atomic loci of molecules from the overall moiety of a given compound.[13]  Central and peripheral are terms that are closely related to concepts such as proximal and distal, but they are so widely applicable that in many respects their flexibility makes them hard to define. Loosely speaking, they distinguish near and far, inside and out, or even organs of vital importance such as heart and lungs, from peripheral organs such as fingers, that undoubtedly may be important, but which it may not be life-threatening to dispense with. Examples of the application of the terms are the distinction between central- and peripheral nervous systems, and between peripheral blood vessels and the central circulatory organs, such as the heart and major vessels. The terms also can apply to large and complex molecules such as proteins, where central amino acid residues are protected from antibodies or the like, but peripheral residues are important in docking and other interactions. Other examples include Central and peripheral circadian clocks,[14] and central versus peripheral vision.[15]   These two terms relate to the distance of a structure from the surface of an animal.  Deep (from Old English) refers to something further away from the surface of the organism. For example, the external oblique muscle of the abdomen is deep to the skin. \"Deep\" is one of the few anatomical terms of location derived from Old English rather than Latin – the anglicised Latin term would have been \"profound\" (from Latin profundus, meaning \\'due to depth\\').  Superficial (from Latin superficies, meaning \\'surface\\') refers to something near the outer surface of the organism. For example, in skin the epidermis is superficial to the subcutis.  These two terms, used in anatomy and embryology, refer to back (dorsal) and front or belly (ventral) of an organism.  The dorsal (from Latin dorsum, meaning \\'back\\') surface of an organism refers to the back, or upper side, of an organism. If talking about the skull, the dorsal side is the top.[16]  The ventral (from Latin venter, meaning \\'belly\\') surface refers to the front, or lower side, of an organism.[16]  For example, in a fish the pectoral fins are dorsal to the anal fin, but ventral to the dorsal fin.    Specific terms exist to describe how close or far something is to the head or tail of an animal. To describe how close to the head of an animal something is, three distinct terms are used:  Rostral (from Latin rostrum, meaning \\'beak, nose\\'), meaning situated toward the oral or nasal region, or in the case of the brain, toward the tip of the frontal lobe. Cranial (from Greek κρανίον, meaning \\'skull\\') or cephalic (from Greek κεφαλή, meaning \\'head\\').[2] Caudal (from Latin cauda, meaning \\'tail\\') is used to describe how close something is to the trailing end of an organism. For example, in horses, the eyes are caudal to the nose and rostral to the back of the head.  These terms are generally preferred in veterinary medicine and not used as often in human medicine.[2][17][18] In humans, \"cranial\" and \"cephalic\" are used to refer to the skull, with \"cranial\" being used more commonly. The term \"rostral\" is rarely used in human anatomy, apart from embryology, and refers more to the front of the face than the superior aspect of the organism. Similarly, the term \"caudal\" is only occasionally used in human anatomy.[10] This is because the brain is situated at the superior part of the head whereas the nose is situated in the anterior part. Thus, the \"rostrocaudal axis\" refers to a C shape (see image).  The location of anatomical structures can also be described with relation to different anatomical landmarks.  Structures may be described as being at the level of a specific spinal vertebra, depending on the section of the vertebral column the structure is at. The position is often abbreviated. For example, structures at the level of the fourth cervical vertebra may be abbreviated as \"C4\", at the level of the fourth thoracic vertebra \"T4\", and at the level of the third lumbar vertebra \"L3\". Because the sacrum and coccyx are fused, they are not often used to provide location.  References may also take origin from superficial anatomy, made to landmarks that are on the skin or visible underneath. For example, structures may be described relative to the anterior superior iliac spine, the medial malleolus or the medial epicondyle.  Anatomical lines, theoretical lines drawn through structures, are also used to describe anatomical location. For example, the mid-clavicular line is used as part of the cardiac exam in medicine to feel the apex beat of the heart.  Fields such as osteology, palaeontology and dentistry apply special terms of location to describe the mouth and teeth. This is because although teeth may be aligned with their main axes within the jaw, some different relationships require special terminology as well; for example teeth also can be rotated, and in such contexts terms like \"anterior\" or \"lateral\" become ambiguous.[19][20] Terms such as \"distal\" and \"proximal\" are also redefined to mean the distance away or close to the mandibular symphysis. Terms used to describe structures include \"buccal\" (from Latin bucca, meaning \\'cheek\\') and \"palatal\" (from Latin) referring to structures close to the cheek and hard palate respectively.  Several anatomical terms are particular to the hands and feet.  For improved clarity, the directional term palmar (from Latin palma, meaning \\'palm of the hand\\') is usually used to describe the front of the hand, and dorsal is the back of the hand. For example, the top of a dog\\'s paw is its dorsal surface; the underside, either the palmar (on the forelimb) or the plantar (on the hindlimb) surface. The palmar fascia is palmar to the tendons of muscles which flex the fingers, and the dorsal venous arch is so named because it is on the dorsal side of the foot.  Volar can also be used to refer to the underside of the palm or sole, which are themselves also sometimes used to describe location as palmar and plantar. For example, volar pads are those on the underside of hands, fingers, feet, and toes.  These terms are used to avoid confusion when describing the median surface of the hand and what is the \"anterior\" or \"posterior\" surface – \"anterior\" can be used to describe the palm of the hand, and \"posterior\" can be used to describe the back of the hand and arm. This confusion can arise because the forearm can pronate and supinate.  Similarly, in the forearm, for clarity, the sides are named after the bones. Structures closer to the radius are radial, structures closer to the ulna are ulnar, and structures relating to both bones are referred to as radioulnar. Similarly, in the lower leg, structures near the tibia (shinbone) are tibial and structures near the fibula are fibular (or peroneal).  Most terms of anatomical location are relative to linear motion (translation) along the X- Y- and Z-axes, but there are other degrees of freedom as well, in particular, rotation around any of those three axes.  Anteversion and retroversion are complementary anatomical terms of location, describing the degree to which an anatomical structure is rotated forwards (towards the front of the body) or backwards (towards the back of the body) respectively, relative to some datum position. The terms also describe the positioning of surgical implants, such as in arthroplasty.  Anteversion refers to an anatomical structure being tilted further forward than normal, whether pathologically or incidentally. For example, there may be a need to measure the anteversion of the neck of a bone such as a femur.[21] For example, a woman\\'s uterus typically is anteverted, tilted slightly forward. A misaligned pelvis may be anteverted, that is to say tilted forward to some relevant degree. Retroversion is rotation around the same axis as that of anteversion, but in the opposite sense, that is to say, tilting back. A structure so affected is described as being retroverted. As with anteversion, retroversion is a completely general term and can apply to a backward tilting of such hard structures as bones, soft organs such as uteri, or surgical implants. Several other terms are also used to describe location. These terms are not used to form the fixed axes. Terms include:  Axial (from Latin axis, meaning \\'axle\\'): around the central axis of the organism or the extremity. Two related terms, \"abaxial\" and \"adaxial\", refer to locations away from and toward the central axis of an organism, respectively Parietal (from Latin paries, meaning \\'wall\\'): pertaining to the wall of a body cavity. For example, the parietal peritoneum is the lining on the inside of the abdominal cavity. Parietal can also refer specifically to the parietal bone of the skull or associated structures. Posteromedial (from Latin posterus, meaning \\'coming after\\', and medius, meaning \\'middle\\'): situated towards the middle of the posterior surface. Posterosuperior (from Latin posterus, meaning \\'coming after\\' and superior): situated towards the upper part of the posterior surface. Terminal (from Latin terminus, meaning \\'boundary or end\\') at the extremity of a (usually projecting) structure, as in \"...an antenna with a terminal sensory hair\". Visceral and viscus (from Latin viscera, meaning \\'internal organs\\'): associated with organs within the body\\'s cavities. For example, the stomach is covered with a lining called the visceral peritoneum as opposed to the parietal peritoneum. Viscus can also be used to mean \"organ\". For example, the stomach is a viscus within the abdominal cavity. Directional and locational prefixes can modify many anatomical and morphological terms, sometimes in formally standard usage, but often attached arbitrarily according to need or convenience.  Prefixes  Sub- (from Latin sub, meaning \\'preposition beneath, close to, nearly etc\\') appended as a prefix, with or without the hyphen, qualifies terms in various senses. Consider subcutaneous as meaning beneath the skin, subterminal meaning near to the end of a structure. Sub- also may mean \"nearly\" or \"more-or-less\"; for instance subglobular means almost globular. In many usages sub- is similar in application to \"hypo-\" Hypo- (from Ancient Greek ὑπό, meaning \\'under\\') Like \"sub\" in various senses as in hypolingual nerve beneath the tongue, or hypodermal fat beneath the skin Infra- (from Latin infra, meaning \\'preposition beneath, below etc\\') Similar to \"sub\"; a direct opposite to super- and supra-, as in Infratemporal space or infraorbital. Inter- (from Latin inter, meaning \\'between\\'): between two other structures. For example, the navel is intermediate to the left arm and the contralateral (right) leg. The intercostal muscles run between the ribs. Super- or Supra- (from Latin super, supra, meaning \\'above, on top of, beyond etc\\') appended as a prefix, with or without the hyphen, as in superciliary arches or supraorbital Suffixes  -ad (from Latin ad, meaning \\'towards or up to\\') Commonly when, for example, one anatomical feature is nearer to something than another, one may use an expression such as \"nearer the distal end\" or \"distal to\". However, an unambiguous and concise convention is to use the Latin suffix -ad, meaning \"towards\", or sometimes \"to\". [11] So for example, \"distad\" means \"in the distal direction\", and \"distad of the femur\" means \"beyond the femur in the distal direction\". The suffix may be used very widely, as in the following examples: anteriad (towards the anterior), apicad (towards the apex), basad (towards the basal end), caudad, centrad, cephalad (towards the cephalic end), craniad, dextrad, dextrocaudad, dextrocephalad, distad, dorsad, ectad (towards the ectal, or exterior, direction), entad (towards the interior), laterad, mediad, mesad, neurad, orad, posteriad, proximad, rostrad, sinistrad, sinistrocaudad, sinistrocephalad, ventrad.[22]  The large variety of body shapes present in invertebrates presents a difficult problem when attempting to apply standard directional terms. Depending on the organism, some terms are taken by analogy from vertebrate anatomy, and appropriate novel terms are applied as needed. Some such borrowed terms are widely applicable in most invertebrates; for example proximal, literally meaning \"near\" refers to the part of an appendage nearest to where it joins the body, and distal, literally meaning \"standing away from\" is used for the part furthest from the point of attachment. In all cases, the usage of terms is dependent on the body plan of the organism.  For example, especially in organisms without distinct heads for reasons of broader applicability, \"anterior\" is usually preferred.[2][17][18]  As humans are approximately bilaterally symmetrical organisms,[1] anatomical descriptions usually use the same terms as those for vertebrates and other members of the taxonomic group Bilateria. However, for historical and other reasons, standard human directional terminology has several differences from that used for other bilaterally symmetrical organisms.  The terms of zootomy and anatomy came into use at a time when all scientific communication took place in Latin. In their original Latin forms the respective meanings of \"anterior\" and \"posterior\" are in front of (or before) and behind (or after), those of \"dorsal\" and \"ventral\" are toward the spine and toward the belly, and those of \"superior\" and \"inferior\" are above and below.  Humans, however, have the rare property of having an upright torso. This makes their anterior/posterior and dorsal/ventral directions the same, and the inferior/superior directions necessary.[23]  Most animals, furthermore, are capable of moving relative to their environment. So while \"up\" might refer to the direction of a standing human\\'s head, the same term (\"up\") might be used to refer to the direction of the belly of a supine human. It is also necessary to employ some specific anatomical knowledge in order to apply the terminology unambiguously: For example, while the ears would be superior to (above) the shoulders in a human, this fails when describing the armadillo, where the shoulders are above the ears. Thus, in veterinary terminology, the ears would be cranial to (i.e., \"toward the head from\") the shoulders in the armadillo, the dog, the kangaroo, or any other terrestrial vertebrate, including the human. Likewise, while the belly is considered anterior to (in front of) the back in humans, this terminology fails for the flounder, the armadillo, and the dog. In veterinary terms, the belly would be ventral (\"toward the abdomen\") in all vertebrates.  While it would be possible to introduce a system of axes that is completely consistent between humans and other vertebrates by having two separate pairs of axes, one used exclusively for the head (e.g., anterior/posterior and inferior/superior) and the other exclusively for the torso (e.g., dorsal/ventral and caudal/rostral, or \"toward the tail\"/\"toward the beak\"), doing so would require the renaming of many anatomical structures.  In organisms with a changeable shape, such as amoeboid organisms, most directional terms are meaningless, since the shape of the organism is not constant and no distinct axes are fixed. Similarly, in spherically symmetrical organisms, there is nothing to distinguish one line through the centre of the organism from any other. An indefinite number of triads of mutually perpendicular axes could be defined, but any such choice of axes would be useless, as nothing would distinguish a chosen triad from any others. In such organisms, only terms such as superficial and deep, or sometimes proximal and distal, are usefully descriptive.  In organisms that maintain a constant shape and have one dimension longer than the other, at least two directional terms can be used. The long or longitudinal axis is defined by points at the opposite ends of the organism. Similarly, a perpendicular transverse axis can be defined by points on opposite sides of the organism. There is typically no basis for the definition of a third axis. Usually such organisms are planktonic (free-swimming) protists, and are nearly always viewed on microscope slides, where they appear essentially two-dimensional. In some cases a third axis can be defined, particularly where a non-terminal cytostome or other unique structure is present.[18]  Some elongated protists have distinctive ends of the body. In such organisms, the end with a mouth (or equivalent structure, such as the cytostome in Paramecium or Stentor), or the end that usually points in the direction of the organism\\'s locomotion (such as the end with the flagellum in Euglena), is normally designated as the anterior end. The opposite end then becomes the posterior end.[18] Properly, this terminology would apply only to an organism that is always planktonic (not normally attached to a surface), although the term can also be applied to one that is sessile (normally attached to a surface).[24]   Organisms that are attached to a substrate, such as sponges, or some animal-like protists also have distinctive ends. The part of the organism attached to the substrate is usually referred to as the basal end (from Latin basis, meaning \\'support/foundation\\'), whereas the end furthest from the attachment is referred to as the apical end (from Latin apex, meaning \\'peak/tip\\').  Radially symmetrical organisms include those in the group Radiata – primarily jellyfish, sea anemones and corals and the comb jellies.[2][18] Adult echinoderms, such as starfish, sea urchins, sea cucumbers and others are also included, since they are pentaradial, meaning they have five discrete rotational symmetry. Echinoderm larvae are not included, since they are bilaterally symmetrical.[2][18] Radially symmetrical organisms always have one distinctive axis.  Cnidarians (jellyfish, sea anemones and corals) have an incomplete digestive system, meaning that one end of the organism has a mouth, and the opposite end has no opening from the gut (coelenteron).[18] For this reason, the end of the organism with the mouth is referred to as the oral end (from Latin ōrālis, meaning \\'of the mouth\\'), and the opposite surface is the aboral end (from Latin ab-, meaning \\'away from\\').  Unlike vertebrates, cnidarians have no other distinctive axes. \"Lateral\", \"dorsal\", and \"ventral\" have no meaning in such organisms, and all can be replaced by the generic term peripheral (from Ancient Greek περιφέρεια, meaning \\'circumference\\'). Medial can be used, but in the case of radiates indicates the central point, rather than a central axis as in vertebrates. Thus, there are multiple possible radial axes and medio-peripheral (half-) axes. However, some biradially symmetrical comb jellies do have distinct \"tentacular\" and \"pharyngeal\" axes[25] and are thus anatomically equivalent to bilaterally symmetrical animals.  As with vertebrates, appendages that move independently of the body (tentacles in cnidarians and comb jellies), have a definite proximodistal axis (Fig. 9).    Two specialized terms are useful in describing views of arachnid legs and pedipalps. Prolateral refers to the surface of a leg that is closest to the anterior end of an arachnid\\'s body. Retrolateral refers to the surface of a leg that is closest to the posterior end of an arachnid\\'s body.[26]  Because of the unusual nature and positions of the eyes of the Araneae (spiders), and their importance in taxonomy, evolution and anatomy, special terminology with associated abbreviations has become established in arachnology. Araneae normally have eight eyes in four pairs. All the eyes are on the carapace of the prosoma, and their sizes, shapes and locations are characteristic of various spider families and other taxa. In some taxa not all four pairs of eyes are present, the relevant species having only three, two, or one pair of eyes. Some species (mainly troglobites) have no functional eyes at all.  In what is seen as the likeliest ancestral arrangement of the eyes of the Araneae, there are two roughly parallel, horizontal, symmetrical, transverse rows of eyes, each containing two symmetrically placed pairs, respectively called: anterior and posterior lateral eyes (ALE) and (PLE); and anterior and posterior median eyes (AME) and (PME).  As a rule it is not difficult to guess which eyes are which in a living or preserved specimen, but sometimes it can be. Apart from the fact that in some species one or more pairs may be missing, sometimes eyes from the posterior and anterior rows may be very close to each other, or even fused. Also, either one row or both might be so grossly curved that some of the notionally anterior eyes actually may lie posterior to some of the eyes in the posterior row. In some species the curve is so gross that the eyes apparently are arranged into two anteroposterior parallel rows of eyes.     Geometric terms of location Standard anatomical position Anatomical terms of motion – Terms describing motion Anatomical terms of muscle Anatomical terms of bone Anatomical terms of neuroanatomy Categories:  Category:Glossaries of medicine Category:Glossaries of science Handedness – Better performance or individual preference for use of a hand Laterality Proper right and proper left – terms for unambiguous directions, like port and starboard Reflection symmetry Sinistral and dextral Direction (disambiguation) Port and starboard – Nautical terms for direction, another example of terms of directionality that do not depend on the location of the observer for things that are bilaterally symmetrical Clockwise Cardinal Directions Blocking (stage)\\n',\n",
              " '  Tardigrades (/ˈtɑːrdɪɡreɪd/), known colloquially as water bears or moss piglets,[1][2][3][4] are a phylum of water-dwelling eight-legged segmented micro-animals.[1][5] They were first described by the German zoologist Johann August Ephraim Goeze in 1773, who called them little water bears. In 1777, the Italian biologist Lazzaro Spallanzani named them Tardigrada, which means \"slow steppers\".[6]  They have been found everywhere, from mountaintops to the deep sea and mud volcanoes,[7] and from tropical rainforests to the Antarctic.[8] Tardigrades are among the most resilient animals known,[9][10] with individual species able to survive extreme conditions—such as exposure to extreme temperatures, extreme pressures (both high and low), air deprivation, radiation, dehydration, and starvation—that would quickly kill most other known forms of life. Tardigrades have survived exposure to outer space.[11][12] About 1,300 known species[13] form the phylum Tardigrada, a part of the superphylum Ecdysozoa. The earliest known true members of the group are known from Cretaceous amber in North America, but are essentially modern forms, and therefore likely have a significantly earlier origin, as they diverged from their closest relatives in the Cambrian, over 500 million years ago.  Tardigrades are usually about 0.5 mm (0.02 in) long when fully grown.[1] They are short and plump, with four pairs of legs, each ending in claws (usually four to eight) or sucking disks.[1][14] Tardigrades are prevalent in mosses and lichens and feed on plant cells, algae, and small invertebrates. When collected, they may be viewed under a low-power microscope, making them accessible to students and amateur scientists.[15]  Johann August Ephraim Goeze originally named the tardigrade kleiner Wasserbär, meaning \"little water-bear\" in German (today, they are often referred to in German as Bärtierchen or \"little bear-animal\"). The name Tardigradum means \"slow walker\" and was given by Lazzaro Spallanzani in 1777.[16]  The name \"water-bear\" comes from the way they walk, reminiscent of a bear\\'s gait. The biggest adults may reach a body length of 1.5 mm (0.059 in), the smallest below 0.1 mm. Newly hatched tardigrades may be smaller than 0.05 mm.  Tardigrades are often found on lichens and mosses. Other environments are dunes, seasides, soil, leaf litter, and marine or freshwater sediments, where they may occur quite frequently (up to 25,000 animals per litre). Tardigrades, in the case of Echiniscoides wyethi,[17] may be found on barnacles.[18] Tardigrades can be often found by soaking a piece of moss in water.[19]  Tardigrades have barrel-shaped bodies with four pairs of stubby legs. Most range from 0.3 to 0.5 mm (0.012 to 0.020 in) in length, although the largest species may reach 1.2 mm (0.047 in). The body consists of a head, three body segments each with a pair of legs, and a caudal segment with a fourth pair of legs. The legs are without joints, while the feet have four to eight claws each. The cuticle contains chitin and protein and is moulted periodically. The first three pairs of legs are directed downward along the sides, and are the primary means of locomotion, while the fourth pair is directed backward on the last segment of the trunk and is used primarily for grasping the substrate.[20]  Tardigrades lack several Hox genes and a large intermediate region of the body axis. In insects, this corresponds to the entire thorax and the abdomen. Practically the whole body, except for the last pair of legs, is made up of just the segments that are homologous to the head region in arthropods.[21]  All adult tardigrades of the same species have the same number of cells (see eutely). Some species have as many as 40,000 cells in each adult, while others have far fewer.[22][23]  The body cavity consists of a haemocoel, but the only place where a true coelom can be found is around the gonad. No respiratory organs are found, with gas exchange able to occur across the entirety of the body. Some tardigrades have three tubular glands associated with the rectum; these may be excretory organs similar to the Malpighian tubules of arthropods, although the details remain unclear.[24] Also nephridia are absent.[25]  The tubular mouth is armed with stylets, which are used to pierce the plant cells, algae, or small invertebrates on which the tardigrades feed, releasing the body fluids or cell contents. The mouth opens into a triradiate, muscular, sucking pharynx. The stylets are lost when the animal molts, and a new pair is secreted from a pair of glands that lie on either side of the mouth. The pharynx connects to a short esophagus, and then to an intestine that occupies much of the length of the body, which is the main site of digestion. The intestine opens, via a short rectum, to an anus located at the terminal end of the body. Some species only defecate when they molt, leaving the feces behind with the shed cuticle.[24]  The brain develops in a bilaterally symmetric pattern.[26] The brain includes multiple lobes, mostly consisting of three bilaterally paired clusters of neurons.[27] The brain is attached to a large ganglion below the esophagus, from which a double ventral nerve cord runs the length of the body. The cord possesses one ganglion per segment, each of which produces lateral nerve fibres that run into the limbs. Many species possess a pair of rhabdomeric pigment-cup eyes, and numerous sensory bristles are on the head and body.[28]  Tardigrades all possess a buccopharyngeal apparatus (swallowing device made of muscles and spines that activates an inner jaw and begins digestion and movement along the throat and intestine[29]) which, along with the claws, is used to differentiate species.  Although some species are parthenogenic, both males and females are usually present, although females are frequently larger and more common. Both sexes have a single gonad located above the intestine. Two ducts run from the testes in males, opening through a single pore in front of the anus. In contrast, females have a single duct opening either just above the anus or directly into the rectum, which thus forms a cloaca.[24]  Tardigrades are oviparous, and fertilization is usually external. Mating occurs during the molt with the eggs being laid inside the shed cuticle of the female and then covered with sperm. A few species have internal fertilization, with mating occurring before the female fully sheds her cuticle. In most cases, the eggs are left inside the shed cuticle to develop, but some species attach them to nearby substrate.[24]  The eggs hatch after no more than 14 days, with the young already possessing their full complement of adult cells. Growth to the adult size, therefore, occurs by enlargement of the individual cells (hypertrophy), rather than by cell division. Tardigrades may molt up to 12 times.[24]  Most tardigrades are phytophagous (plant eaters) or bacteriophagous (bacteria eaters), but some are carnivorous to the extent that they eat smaller species of tardigrades (e.g., Milnesium tardigradum).[30][31]  Tardigrades share morphological characteristics with many species that differ largely by class. Biologists have a difficult time finding verification among tardigrade species because of this relationship.[clarification needed] These animals are most closely related to the early evolution of arthropods.[32] Tardigrade fossils go as far back as the Cretaceous period in North America. Tardigrades are considered cosmopolitan and can be located in regions all over the world. The eggs and cysts of tardigrades are so durable that they can be carried great distances on the feet of other animals.[14]  Tardigrades have survived all five mass extinctions. This has given them a plethora of survival characteristics, including the ability to survive situations that would be fatal to almost all other animals (see the next section).  The lifespan of tardigrades ranges from 3–4 months for some species, up to 2 years for other species, not counting their time in dormant states.[33]  Scientists have reported tardigrades in hot springs, on top of the Himalaya[34] (6,000 m; 20,000 ft, above sea level) to the deep sea (−4,000 m; −13,000 ft) and from the polar regions to the equator, under layers of solid ice, and in ocean sediments. Many species can be found in milder environments such as lakes, ponds, and meadows, while others can be found in stone walls and roofs. Tardigrades are most common in moist environments, but can stay active wherever they can retain at least some moisture.  Tardigrades are thought to be able to survive even complete global mass extinction events due to astrophysical events, such as gamma-ray bursts, or large meteorite impacts.[9][10] Some of them can withstand extremely cold temperatures down to 1 K (−458 °F; −272 °C) (close to absolute zero), while others can withstand extremely hot temperatures up to 420 K (300 °F; 150 °C)[35] for several minutes, pressures about six times greater than those found in the deepest ocean trenches, ionizing radiation at doses hundreds of times higher than the lethal dose for a human, and the vacuum of outer space.[36] Tardigrades that live in harsh conditions undergo an annual process of cyclomorphosis, allowing for survival in sub-zero temperatures.[37]  They are not considered extremophilic because they are not adapted to exploit these conditions, only to endure them. This means that their chances of dying increase the longer they are exposed to the extreme environments,[6] whereas true extremophiles thrive in a physically or geochemically extreme environment that would harm most other organisms.[2][38][39]  Tardigrades are one of the few groups of species that are capable of suspending their metabolism (see cryptobiosis). While in this state, their metabolism lowers to less than 0.01% of normal and their water content can drop to 1% of normal,[36] and they can go without food or water for more than 30 years, only to later rehydrate, forage, and reproduce.[2][40][41][42][43] Many species of tardigrade can survive in a dehydrated state up to five years, or in exceptional cases longer.[44][45] Depending on the environment, they may enter this state via anhydrobiosis, cryobiosis, osmobiosis, or anoxybiosis. Their ability to remain desiccated for such long periods was thought to be largely dependent on the high levels of the nonreducing sugar trehalose, which protects their membranes, although recent research suggests that tardigrades have a unique type of disordered protein that serves a similar purpose: It replaces water in the cells and adopts a glassy, vitrified state when the animals dry out.[46] Their DNA is further protected from radiation by a protein called \"dsup\" (short for damage suppressor).[47][48] In this cryptobiotic state, the tardigrade is known as a tun.[49]  Tardigrades are able to survive in extreme environments that would kill almost any other animal. Extremes at which tardigrades can survive include those of:  Temperature – tardigrades can survive: A few minutes at 151 °C (304 °F)[50] 30 years at −20 °C (−4 °F)[51] A few days at −200 °C (−328 °F; 73 K)[50] A few minutes at −272 °C (−458 °F; 1 K)[52] A few minutes at 151 °C (304 °F)[50] 30 years at −20 °C (−4 °F)[51] A few days at −200 °C (−328 °F; 73 K)[50] A few minutes at −272 °C (−458 °F; 1 K)[52] Research published in 2020 shows that tardigrades are sensitive to high temperatures. Researchers showed it takes 48 hours at 98.8 °F (37.1 °C) to kill half of active tardigrades that have not been acclimated to heat. Acclimation boosted the temperature needed to kill half of active tardigrades to 99.7 °F (37.6 °C). Tardigrades in the tun state fared a bit better, tolerating higher temperatures. It took heating to 180.9 °F (82.7 °C) to kill half of tun-state tardigrades within 1 hour. Longer exposure time decreased the temperature needed for lethality, though. For 24 hours of exposure, 145.6 °F (63.1 °C) was enough to kill half of the tun-state tardigrades. [53]  Pressure – they can withstand the extremely low pressure of a vacuum and also very high pressures, more than 1,200 times atmospheric pressure. Some species can also withstand pressure of 6,000 atmospheres, which is nearly six times the pressure of water in the deepest ocean trench, the Mariana Trench.[22] Dehydration – the longest that living tardigrades have been shown to survive in a dry state is nearly 10 years,[41][42] although there is one report of leg movement, not generally considered \"survival\",[54] in a 120-year-old specimen from dried moss.[55] When exposed to extremely low temperatures, their body composition goes from 85% water to only 3%. Because water expands upon freezing, dehydration ensures the tardigrades’ tissues are not ruptured by the expansion of freezing ice.[56] Radiation – tardigrades can withstand 1,000 times more radiation than other animals,[57] median lethal doses of 5,000 Gy (of gamma rays) and 6,200 Gy (of heavy ions) in hydrated animals (5 to 10 Gy could be fatal to a human).[58] The only explanation found in earlier experiments for this ability was that their lowered water state provides fewer reactants for ionizing radiation.[58] However, subsequent research found that tardigrades, when hydrated, still remain highly resistant to shortwave UV radiation in comparison to other animals, and that one factor for this is their ability to efficiently repair damage to their DNA resulting from that exposure.[59] Irradiation of tardigrade eggs collected directly from a natural substrate (moss) showed a clear dose-related response, with a steep decline in hatchability at doses up to 4 kGy, above which no eggs hatched.[60] The eggs were more tolerant to radiation late in development. No eggs irradiated at the early developmental stage hatched, and only one egg at middle stage hatched, while eggs irradiated in the late stage hatched at a rate indistinguishable from controls.[60]  Environmental toxins – tardigrades are reported to undergo chemobiosis, a cryptobiotic response to high levels of environmental toxins. However, as of 2001, these laboratory results have yet to be verified.[54][55] Tardigrades are the first known animal to survive after exposure to outer space.[61] In September 2007, dehydrated tardigrades were taken into low Earth orbit on the FOTON-M3 mission carrying the BIOPAN astrobiology payload. For 10 days, groups of tardigrades, some of them previously dehydrated, some of them not, were exposed to the hard vacuum of outer space, or vacuum and solar UV radiation.[62][2][63][64] Back on Earth, over 68% of the subjects protected from solar UV radiation were reanimated within 30 minutes following rehydration, although subsequent mortality was high; many of these produced viable embryos.[62][61] In contrast, hydrated samples exposed to the combined effect of vacuum and full solar UV radiation had significantly reduced survival, with only three subjects of Milnesium tardigradum surviving.[62] In May 2011, Italian scientists sent tardigrades on board the International Space Station along with extremophiles on STS-134, the final flight of Space Shuttle Endeavour.[65][66][67] Their conclusion was that microgravity and cosmic radiation \"did not significantly affect survival of tardigrades in flight, and stated that tardigrades represent a useful animal for space research.\"[68][69] In November 2011, they were among the organisms to be sent by the U.S.-based Planetary Society on the Russian Fobos-Grunt mission\\'s Living Interplanetary Flight Experiment to Phobos; however, the launch failed. In August 2019, scientists reported that a capsule containing tardigrades in a cryptobiotic state may have survived for a while on the Moon after the April 2019 crash landing of Beresheet, a failed Israeli lunar lander.[70][71]  Scientists have conducted morphological and molecular studies to understand how tardigrades relate to other lineages of ecdysozoan animals. Two plausible placements have been proposed: tardigrades are either most closely related to Arthropoda and Onychophora, or to nematodes. Evidence for the former is a common result of morphological studies; evidence of the latter is found in some molecular analyses.  The latter hypothesis has been rejected by recent microRNA and expressed sequence tag analyses.[72] Apparently, the grouping of tardigrades with nematodes found in a number of molecular studies is a long branch attraction artifact. Within the arthropod group (called panarthropoda and comprising onychophora, tardigrades and euarthropoda), three patterns of relationship are possible: tardigrades sister to onychophora plus arthropods (the lobopodia hypothesis); onychophora sister to tardigrades plus arthropods (the tactopoda hypothesis); and onychophora sister to tardigrades.[73] Recent analyses indicate that the panarthropoda group is monophyletic, and that tardigrades are a sister group of Lobopodia, the lineage consisting of arthropods and Onychophora.[72][74]  The minute sizes of tardigrades and their membranous integuments make their fossilization both difficult to detect and highly unusual. The only known fossil specimens are those from mid-Cambrian deposits in Siberia and a few rare specimens from Cretaceous amber.[75]  The Siberian tardigrade fossils differ from living tardigrades in several ways. They have three pairs of legs rather than four, they have a simplified head morphology, and they have no posterior head appendages, but they share with modern tardigrades their columnar cuticle construction.[76] Scientists think they represent a stem group of living tardigrades.[75]  Rare specimens in Cretaceous amber have been found in two North American locations. Milnesium swolenskyi, from New Jersey, is the older of the two; its claws and mouthparts are indistinguishable from the living M. tardigradum. The other specimens from amber are from western Canada, some 15–20 million years earlier than M. swolenskyi. One of the two specimens from Canada has been given its own genus and family, Beorn leggi, but it bears a strong resemblance to many living specimens in the family Hypsibiidae.[75][77]  There are multiple lines of evidence that tardigrades are secondarily miniaturized from a larger ancestor,[78] probably a lobopodian and perhaps resembling Aysheaia, which many analyses place close to the divergence of the tardigrade lineage.[79][80]  An alternative hypotheses derives tactopoda from a grade encompassing dinocaridids and Opabinia.[81]  Tardigrade genomes vary in size, from about 75 to 800 megabase pairs of DNA.[82] Hypsibius exemplaris (formerly Hypsibius dujardini) has a compact genome of 100 megabase pairs[83] and a generation time of about two weeks; it can be cultured indefinitely and cryopreserved.[84]  The genome of Ramazzottius varieornatus, one of the most stress-tolerant species of tardigrades, was sequenced by a team of researchers from the University of Tokyo in 2015. While previous research had claimed that around one-sixth of the genome had been acquired from other organisms,[85] it is now known that less than 1.2% of its genes were the result of horizontal gene transfer. They also found evidence of a loss of gene pathways that are known to promote damage due to stress. This study also found a high expression of novel tardigrade-unique proteins, including Damage suppressor (Dsup), which was shown to protect against DNA damage from X-ray radiation. The same team applied the Dsup protein to human cultured cells and found that it suppressed X-ray damage to the human cells by around 40%.[48]  Many organisms that live in aquatic environments feed on species such as nematodes, tardigrades, bacteria, algae, mites, and collembolans.[86] Tardigrades work as pioneer species by inhabiting new developing environments. This movement attracts other invertebrates to populate that space, while also attracting predators.[32]  The 2014 science documentary show Cosmos: A Spacetime Odyssey mentions tardigrades in the second episode on biological evolution.[87] When the characters in the superhero films Ant-Man (2015) and Ant-Man and the Wasp (2018) shrink themselves to enter the \"Quantum Realm\", they encounter tardigrades.[88][89][90] In the 2015 sci-fi horror film Harbinger Down, the characters have to deal with deadly mutated tardigrades.[91][92] The second arc of the comic book Paper Girls (2015) features a pair of tardigrades that have been enlarged to a massive size as a side effect of time travel.[93] Musician Cosmo Sheldrake imagines himself a tardigrade in his 2015 \"Tardigrade Song\".[94][95] In Star Trek: Discovery (2017), the alien \"Ripper\" creature who is used to \"navigate\" through a galactic mycelium network and instantly move the ship from one location in the galaxy to another is referred to as a \"giant space tardigrade\" and said to be a cousin of the tardigrade.[96][97] The 2017 South Park episode \"Moss Piglets\" involves a science experiment in which tardigrades learn to dance to the music of Taylor Swift.[98][99] The 2018 Family Guy episode \"Big Trouble in Little Quahog\" features Stewie and Brian being shrunk to microscopic level, during which they meet a group of friendly tardigrades or \"water bears\" who help them.[100] List of microorganisms tested in outer space Living Interplanetary Flight Experiment, study of selected microorganisms in outer space Panspermia\\n',\n",
              " 'The combined oral contraceptive pill (COCP), often referred to as the birth control pill or colloquially as \"the pill\", is a type of birth control that is designed to be taken orally by women. It includes a combination of an estrogen (usually ethinylestradiol) and a progestogen (specifically a progestin). When taken correctly, it alters the menstrual cycle to eliminate ovulation and prevent pregnancy.  They were first approved for contraceptive use in the United States in 1960, and are a very popular form of birth control. They are currently used by more than 100 million women worldwide and by almost 12 million women in the United States.[8] From 2015–2017, 12.6% of women aged 15–49 in the US reported using oral contraception making it the second most common method of contraception in this age range with female sterilization being the most common method.[9] Use varies widely by country,[10] age, education, and marital status. One third of women aged 16–49 in the United Kingdom currently use either the combined pill or progestogen-only pill (POP),[11][12] compared with less than 3% of women in Japan (as of 1950-2014).[13]  Two forms of combined oral contraceptives are on the World Health Organization\\'s List of Essential Medicines, the most important medications needed in a basic health system.[14] The pill was a catalyst for the sexual revolution.[15]  Combined oral contraceptive pills are a type of oral medication that is designed to be taken every day, at the same time of day, in order to prevent pregnancy.[16][17] There are many different formulations or brands, but the average pack is designed to be taken over a 28-day period, or cycle. For the first 21 days of the cycle, users take a daily pill that contains hormones (estrogen and progestogen). The last 7 days of the cycle are hormone free days. Some packets only contain 21 pills and users are then advised to take no pills for the following week. Other packets contain 7 additional placebo pills, or biologically inactive pills. Some newer formulations have 24 days of active hormone pills, followed by 4 days of placebo (examples include Yaz 28 and Loestrin 24 Fe) or even 84 days of active hormone pills, followed by 7 days of placebo pills (Seasonale).[16] A woman on the pill will have a withdrawal bleed sometime during her placebo pill or no pill days, and is still protected from pregnancy during this time. Then after 28 days, or 91 days depending on which type a person is using, users start a new pack and a new cycle.[18]  If used exactly as instructed, the estimated risk of getting pregnant is 0.3%, or about 3 in 1000 women on COCPs will become pregnant within one year.[19] However, typical use is often not exact due to timing errors, forgotten pills, or unwanted side effects. With typical use, the estimated risk of getting pregnant is about 9%, or about 9 in 100 women on COCP will become pregnant in one year.[20] The perfect use failure rate is based on a review of pregnancy rates in clinical trials, the typical use failure rate is based on a weighted average of estimates from the 1995 and 2002 U.S. National Surveys of Family Growth (NSFG), corrected for underreporting of abortions.[21]  Several factors account for typical use effectiveness being lower than perfect use effectiveness:  mistakes on the part of those providing instructions on how to use the method mistakes on the part of the user conscious user non-compliance with instructions. For instance, someone using oral forms of hormonal birth control might be given incorrect information by a health care provider as to the frequency of intake, forget to take the pill one day, or simply not go to the pharmacy on time to renew the prescription.  COCPs provide effective contraception from the very first pill if started within five days of the beginning of the menstrual cycle (within five days of the first day of menstruation). If started at any other time in the menstrual cycle, COCPs provide effective contraception only after 7 consecutive days use of active pills, so a backup method of contraception (such as condoms) must be used until active pills have been taken for 7 consecutive days. COCPs should be taken at approximately the same time every day.[22][23]  The effectiveness of the combined oral contraceptive pill appears to be similar whether the active pills are taken continuously for prolonged periods of time or if they are taken for 21 active days and 7 days as placebo.[24]  Contraceptive efficacy may be impaired by:  missing more than one active pill in a packet, delay in starting the next packet of active pills (i.e., extending the pill-free, inactive or placebo pill period beyond 7 days), intestinal malabsorption of active pills due to vomiting or diarrhea, drug interactions with active pills that decrease contraceptive estrogen or progestogen levels.[22] In any of these instances, a back up method should be used until consistent use of active pills (for 7 consecutive days) has resumed, the interacting drug has been discontinued or illness has been resolved.  According to CDC guidelines, a pill is only considered \\'missed\\' if 24 hours or more have passed since the last pill taken. If less than 24 hours have passed, the pill is considered \"late.\"[19]  The role of the placebo pills is two-fold: to allow the user to continue the routine of taking a pill every day and to simulate the average menstrual cycle. By continuing to take a pill everyday, users remain in the daily habit even during the week without hormones. Failure to take pills during the placebo week does not impact the effectiveness of the pill, provided that daily ingestion of active pills is resumed at the end of the week.[25]  The placebo, or hormone-free, week in the 28-day pill package simulates an average menstrual cycle, though the hormonal events during a pill cycle are significantly different from those of a normal ovulatory menstrual cycle. Because the pill suppresses ovulation (to be discussed more in the Mechanism of Action section), birth control users do not have true menstrual periods. Instead, it is the lack of hormones for a week that causes a withdrawal bleed.[17] The withdrawal bleeding that occurs during the break from active pills has been thought to be reassuring, a physical confirmation of not being pregnant.[26] The withdrawal bleeding is also predictable. Unexpected breakthrough bleeding can be a possible side effect of longer term active regimens.[27]  Since it is not uncommon for menstruating women to become anemic, some placebo pills may contain an iron supplement.[28][29] This replenishes iron stores that may become depleted during menstruation.  If the pill formulation is monophasic, meaning each hormonal pill contains a fixed dose of hormones, it is possible to skip withdrawal bleeding and still remain protected against conception by skipping the placebo pills altogether and starting directly with the next packet. Attempting this with bi- or tri-phasic pill formulations carries an increased risk of breakthrough bleeding and may be undesirable. It will not, however, increase the risk of getting pregnant.  Starting in 2003, women have also been able to use a three-month version of the pill.[30] Similar to the effect of using a constant-dosage formulation and skipping the placebo weeks for three months, Seasonale gives the benefit of less frequent periods, at the potential drawback of breakthrough bleeding. Seasonique is another version in which the placebo week every three months is replaced with a week of low-dose estrogen.  A version of the combined pill has also been packaged to completely eliminate placebo pills and withdrawal bleeds. Marketed as Anya or Lybrel, studies have shown that after seven months, 71% of users no longer had any breakthrough bleeding, the most common side effect of going longer periods of time without breaks from active pills.  While more research needs to be done to assess the long term safety of using COCP\\'s continuously, studies have shown there may be no difference in short term adverse effects when comparing continuous use versus cyclic use of birth control pills.[31]  The hormones in the pill have also been used to treat other medical conditions, such as polycystic ovary syndrome (PCOS), endometriosis, adenomyosis, acne, hirsutism, amenorrhea, menstrual cramps, menstrual migraines, menorrhagia (excessive menstrual bleeding), menstruation-related or fibroid-related anemia and dysmenorrhea (painful menstruation).[32][20] Besides acne, no oral contraceptives have been approved by the U.S. FDA for the previously mentioned uses despite extensive use for these conditions.[33]  PCOS, or polycystic ovary syndrome, is a syndrome that is caused by hormonal imbalances. Women with PCOS often have higher than normal levels of estrogen all the time because their hormonal cycles are not regular.[17] Over time, high levels of uninhibited estrogen can lead to endometrial hyperplasia, or overgrowth of tissue in the uterus. This overgrowth is more likely to become cancerous than normal endometrial tissue.[34] Thus, although the data varies, it is generally agreed upon by most gynecological societies that due to the high estrogen levels that women with PCOS have, they are at higher risk for endometrial hyperplasia.[35] To reduce this risk, it is often recommended that women with PCOS take hormonal contraceptives to regulate their hormones. Both COCPs and progestin-only methods are recommended. COCPs are preferred in women who also suffer from uncontrolled acne and symptoms of hirsutism, or male patterned hair growth, because COCPs can help treats these symptoms.[17]  For pelvic pain associated with endometriosis, COCPs are considered a first-line medical treatment, along with NSAIDs, GnRH agonists, and aromatase inhibitors.[36] COCPs work to suppress the growth of the extra-uterine endometrial tissue. This works to lessen its inflammatory effects.[17] COCPs, along with the other medical treatments listed above, do not eliminate the extra-uterine tissue growth, they just reduce the symptoms. Surgery is the only definitive treatment. Studies looking at rates of pelvic pain reoccurrence after surgery have shown that continuous use of COCPs is more effective at reducing the recurrence of pain than cyclic use[37]  Similar to endometriosis, adenomyosis is often treated with COCPs to suppress the growth the endometrial tissue that has grown into the myometrium. Unlike endometriosis however, levonorgetrel containing IUDs are more effective at reducing pelvic pain in adenomyosis than COCPs.[17]  Combined oral contraceptives are sometimes prescribed as medication for mild or moderate acne, although none are approved by the U.S. FDA for that sole purpose.[38] Four different oral contraceptives have been FDA approved to treat moderate acne if the person is at least 14 or 15 years old, have already begun menstruating, and need contraception. These include Ortho Tri-Cyclen, Estrostep, Beyaz, and YAZ.[39][40][41]  Although the pill is sometimes prescribed to induce menstruation on a regular schedule for women bothered by irregular menstrual cycles, it actually suppresses the normal menstrual cycle and then mimics a regular 28-day monthly cycle.  Women who are experiencing menstrual dysfunction due to female athlete triad are sometimes prescribed oral contraceptives as pills that can create menstrual bleeding cycles.[42] However, the condition\\'s underlying cause is energy deficiency and should be treated by correcting the imbalance between calories eaten and calories burned by exercise. Oral contraceptives should not be used as an initial treatment for female athlete triad.[42]  While combined oral contraceptives are generally considered to be a relatively safe medication, they are contraindicated for people with certain medical conditions. The World Health Organization and Centers for Disease Control publish guidance, called medical eligibility criteria, on the safety of birth control in the context of medical conditions. Estrogen in high doses can increase a person\\'s risk for blood clots. Current formulations of COCP\\'s do not contain doses high enough to increase the absolute risk of thrombotic events in otherwise healthy people, but people with any pre-existing medical condition that also increases their risk for blood clots makes using COCPs more dangerous.[17] These conditions include but are not limited to high blood pressure, pre-existing cardiovascular disease (such as valvular heart disease or ischemic heart disease[43]), history of thromboembolism or pulmonary embolism, cerebrovascular accident, migraine with aura, a familial tendency to form blood clots (such as familial factor V Leiden), and in smokers over age 35.[44]  COCPs are also contraindicated for people with advanced diabetes, liver tumors, hepatic adenoma or severe cirrhosis of the liver.[44][20] COCPs are metabolized in the liver and thus liver disease can lead to reduced elimination of the medication. People with known or suspected breast cancer, endometrial cancer, or unexplained uterine bleeding should also not take COCPs to avoid health risks.[43]  Women who are known to be pregnant should not take COCPs. Postpartum women who are breastfeeding are also advised not to start COCPs until 4 weeks after birth due to increased risk of blood clots.[19] Severe hypercholesterolemia and hypertriglyceridemia are also currently contraindications, but the evidence showing that COCP\\'s lead to worse outcomes in this population is weak.[19][17] Obesity is not considered to be a contraindication to taking COCPs .[19]  It is generally accepted that the health risks of oral contraceptives are lower than those from pregnancy and birth,[45] and \"the health benefits of any method of contraception are far greater than any risks from the method\".[46] Some organizations have argued that comparing a contraceptive method to no method (pregnancy) is not relevant—instead, the comparison of safety should be among available methods of contraception.[47]  Different sources note different incidences of side effects. The most common side effect is breakthrough bleeding. A 1992 French review article said that as many as 50% of new first-time users discontinue the birth control pill before the end of the first year because of the annoyance of side effects such as breakthrough bleeding and amenorrhea.[48] A 2001 study by the Kinsey Institute exploring predictors of discontinuation of oral contraceptives found that 47% of 79 women discontinued the pill.[49] One 1994 study found that women using birth control pills blinked 32% more often than those not using the contraception.[50]  On the other hand, the pills can sometimes improve conditions such as pelvic inflammatory disease, dysmenorrhea, premenstrual syndrome, and acne,[51] reduce symptoms of endometriosis and polycystic ovary syndrome, and decrease the risk of anemia.[52] Use of oral contraceptives also reduces lifetime risk of ovarian cancer.[53][54]  Nausea, vomiting, headache, bloating, breast tenderness, swelling of the ankles/feet (fluid retention), or weight change may occur. Vaginal bleeding between periods (spotting) or missed/irregular periods may occur, especially during the first few months of use.[55]  Combined oral contraceptives increase the risk of venous thromboembolism (including deep vein thrombosis (DVT) and pulmonary embolism (PE)).[56]  COC pills with more than 50 µg of estrogen increase the risk of ischemic stroke and myocardial infarction but lower doses appear safe.[57] These risks are greatest in women with additional risk factors, such as smoking (which increases risk substantially) and long-continued use of the pill, especially in women over 35 years of age.[58]  The overall absolute risk of venous thrombosis per 100,000 woman-years in current use of combined oral contraceptives is approximately 60, compared with 30 in non-users.[59] The risk of thromboembolism varies with different types of birth control pills; compared with combined oral contraceptives containing levonorgestrel (LNG), and with the same dose of estrogen and duration of use, the rate ratio of deep venous thrombosis for combined oral contraceptives with norethisterone is 0.98, with norgestimate 1.19, with desogestrel (DSG) 1.82, with gestodene 1.86, with drospirenone (DRSP) 1.64, and with cyproterone acetate 1.88.[59] In comparison, venous thromboembolism occurs in 100–200 per 100.000 pregnant women every year.[59]  One study showed more than a 600% increased risk of blood clots for women taking COCPs with drospirenone compared with non-users, compared with 360% higher for women taking birth control pills containing levonorgestrel.[60] The U.S. Food and Drug Administration (FDA) initiated studies evaluating the health of more than 800,000 women taking COCPs and found that the risk of VTE was 93% higher for women who had been taking drospirenone COCPs for 3 months or less and 290% higher for women taking drospirenone COCPs for 7–12 months, compared with women taking other types of oral contraceptives.[61]  Based on these studies, in 2012 the FDA updated the label for drospirenone COCPs to include a warning that contraceptives with drospirenone may have a higher risk of dangerous blood clots.[62]   A systematic review in 2010 did not support an increased overall cancer risk in users of combined oral contraceptive pills, but did find a slight increase in breast cancer risk among current users, which disappears 5–10 years after use has stopped.[63]  COC decreased the risk of ovarian cancer, endometrial cancer,[22] and colorectal cancer.[3][51][64] Two large cohort studies published in 2010 both found a significant reduction in adjusted relative risk of ovarian and endometrial cancer mortality in ever-users of OCs compared with never-users.[2][65]  The use of oral contraceptives (birth control pills) for five years or more decreases the risk of ovarian cancer in later life by 50%.[64] Combined oral contraceptive use reduces the risk of ovarian cancer by 40% and the risk of endometrial cancer by 50% compared with never users. The risk reduction increases with duration of use, with an 80% reduction in risk for both ovarian and endometrial cancer with use for more than 10 years. The risk reduction for both ovarian and endometrial cancer persists for at least 20 years.[22]  A report by a 2005 International Agency for Research on Cancer (IARC) working group said COCs increase the risk of cancers of the breast (among current and recent users),[3] cervix and liver (among populations at low risk of hepatitis B virus infection).[3] A 2013 meta-analysis concluded that every use of birth control pills is associated with a modest increase in the risk of breast cancer (relative risk 1.08) and a reduced risk of colorectal cancer (relative risk 0.86) and endometrial cancer (relative risk 0.57). Cervical cancer risk in those infected with human papilloma virus is increased.[66] A similar small increase in breast cancer risk was seen in other meta analyses.[67][68]  A 2013 Cochrane systematic review found that studies of combination hormonal contraceptives showed no large difference in weight when compared with placebo or no intervention groups.[69] The evidence was not strong enough to be certain that contraceptive methods do not cause some weight change, but no major effect was found.[69] This review also found \"that women did not stop using the pill or patch because of weight change.\"[69]  COCPs may increase natural vaginal lubrication.[70] Other women experience reductions in libido while on the pill, or decreased lubrication.[70][71] Some researchers question a causal link between COCP use and decreased libido;[72] a 2007 study of 1700 women found COCP users experienced no change in sexual satisfaction.[73] A 2005 laboratory study of genital arousal tested fourteen women before and after they began taking COCPs. The study found that women experienced a significantly wider range of arousal responses after beginning pill use; decreases and increases in measures of arousal were equally common.[74][75]  A 2006 study of 124 pre-menopausal women measured sex hormone binding globulin (SHBG), including before and after discontinuation of the oral contraceptive pill. Women continuing use of oral contraceptives had SHBG levels four times higher than those who never used it, and levels remained elevated even in the group that had discontinued its use.[76][77] Theoretically, an increase in SHBG may be a physiologic response to increased hormone levels, but may decrease the free levels of other hormones, such as androgens, because of the unspecificity of its sex hormone binding.  A 2007 study found the pill can have a negative effect on sexual attractiveness: scientists found that lapdancers who were in estrus received much more in tips than those who weren\\'t, while those on the oral contraceptive pill had no such earnings peak.[78]  Low levels of serotonin, a neurotransmitter in the brain, have been linked to depression. High levels of estrogen, as in first-generation COCPs, and progestin, as in some progestin-only contraceptives, have been shown to lower the brain serotonin levels by increasing the concentration of a brain enzyme that reduces serotonin. A growing body of research evidence has suggested that hormonal contraception may have an adverse effect on women\\'s psychological health.[79][80][81] In 2016, a large Danish study of one million women (followed-up from January 2000 to December 2013) showed that use of COCPs, especially among adolescents, was associated with a statistically significantly increased risk of subsequent depression, although the sizes of the effects are small (for example, 2.1% of the women who took any form of oral birth control were prescribed anti-depressants for the first time, compared to 1.7% of women in the control group).[80] Similarly, in 2018, the findings from a large nationwide Swedish cohort study investigating the effect of hormonal contraception on mental health amongst women (n=815,662, aged 12–30) were published, highlighting an association between hormonal contraception and subsequent use of psychotropic drugs for women of reproductive age.[81] This association was particularly large for young adolescents (aged 12–19).[81] The authors call for further research into the influence of different kinds of hormonal contraception on young women\\'s psychological health.[81]  Progestin-only contraceptives are known to worsen the condition of women who are already depressed.[82][83] However, current medical reference textbooks on contraception[22] and major organizations such as the American ACOG,[84] the WHO,[85] and the United Kingdom\\'s RCOG[86] agree that current evidence indicates low-dose combined oral contraceptives are unlikely to increase the risk of depression, and unlikely to worsen the condition in women that are currently depressed.  Bradykinin lowers blood pressure by causing blood vessel dilation. Certain enzymes are capable of breaking down bradykinin (Angiotensin Converting Enzyme, Aminopeptidase P). Progesterone can increase the levels of Aminopeptidase P (AP-P), thereby increasing the breakdown of bradykinin, which increases the risk of developing hypertension.[87]  Other side effects associated with low-dose COCPs are leukorrhea (increased vaginal secretions), reductions in menstrual flow, mastalgia (breast tenderness), and decrease in acne. Side effects associated with older high-dose COCPs include nausea, vomiting, increases in blood pressure, and melasma (facial skin discoloration); these effects are not strongly associated with low-dose formulations.  Excess estrogen, such as from birth control pills, appears to increase cholesterol levels in bile and decrease gallbladder movement, which can lead to gallstones.[88] Progestins found in certain formulations of oral contraceptive pills can limit the effectiveness of weight training to increase muscle mass.[89] This effect is caused by the ability of some progestins to inhibit androgen receptors. One study claims that the pill may affect what male body odors a woman prefers, which may in turn influence her selection of partner.[90][91][92] Use of combined oral contraceptives is associated with a reduced risk of endometriosis, giving a relative risk of endometriosis of 0.63 during active use, yet with limited quality of evidence according to a systematic review.[93]  Combined oral contraception decreases total testosterone levels by approximately 0.5 nmol/l, free testosterone by approximately 60%, and increases the amount of sex hormone binding globulin (SHBG) by approximately 100 nmol/l. Contraceptives containing second generation progestins and/or estrogen doses of around 20 –25 mg EE were found to have less impact on SHBG concentrations.[94] Combined oral contraception may also reduce bone density.[95]  Some drugs reduce the effect of the pill and can cause breakthrough bleeding, or increased chance of pregnancy. These include drugs such as rifampicin, barbiturates, phenytoin and carbamazepine. In addition cautions are given about broad spectrum antibiotics, such as ampicillin and doxycycline, which may cause problems \"by impairing the bacterial flora responsible for recycling ethinylestradiol from the large bowel\" (BNF 2003).[96][97][98][99]  The traditional medicinal herb St John\\'s Wort has also been implicated due to its upregulation of the P450 system in the liver which could increase the metabolism of ethinyl estradiol and progestin components of some combined oral contraception.[100]  Combined oral contraceptive pills were developed to prevent ovulation by suppressing the release of gonadotropins. Combined hormonal contraceptives, including COCPs, inhibit follicular development and prevent ovulation as a primary mechanism of action.[101][102][103][104]  Progestogen negative feedback decreases the pulse frequency of gonadotropin-releasing hormone (GnRH) release by the hypothalamus, which decreases the secretion of follicle-stimulating hormone (FSH) and greatly decreases the secretion of luteinizing hormone (LH) by the anterior pituitary. Decreased levels of FSH inhibit follicular development, preventing an increase in estradiol levels. Progestogen negative feedback and the lack of estrogen positive feedback on LH secretion prevent a mid-cycle LH surge. Inhibition of follicular development and the absence of an LH surge prevent ovulation.[101][102][103]  Estrogen was originally included in oral contraceptives for better cycle control (to stabilize the endometrium and thereby reduce the incidence of breakthrough bleeding), but was also found to inhibit follicular development and help prevent ovulation. Estrogen negative feedback on the anterior pituitary greatly decreases the secretion of FSH, which inhibits follicular development and helps prevent ovulation.[101][102][103]  Another primary mechanism of action of all progestogen-containing contraceptives is inhibition of sperm penetration through the cervix into the upper genital tract (uterus and fallopian tubes) by decreasing the water content and increasing the viscosity of the cervical mucus.[101]  The estrogen and progestogen in COCPs have other effects on the reproductive system, but these have not been shown to contribute to their contraceptive efficacy:[101]  Slowing tubal motility and ova transport, which may interfere with fertilization. Endometrial atrophy and alteration of metalloproteinase content, which may impede sperm motility and viability, or theoretically inhibit implantation. Endometrial edema, which may affect implantation. Insufficient evidence exists on whether changes in the endometrium could actually prevent implantation. The primary mechanisms of action are so effective that the possibility of fertilization during COCP use is very small. Since pregnancy occurs despite endometrial changes when the primary mechanisms of action fail, endometrial changes are unlikely to play a significant role, if any, in the observed effectiveness of COCPs.[101]  Oral contraceptives come in a variety of formulations, some containing both estrogen and progestins, and some only containing progestin. Doses of component hormones also vary among products, and some pills are monophasic (delivering the same dose of hormones each day) while others are multiphasic (doses vary each day).  COCPs have been somewhat inconsistently grouped into \"generations\" in the medical literature based on when they were introduced.[105][106]  First generation COCPs are sometimes defined as those containing the progestins noretynodrel, norethisterone, norethisterone acetate, or etynodiol acetate;[105] and sometimes defined as all COCPs containing ≥ 50 µg ethinylestradiol.[106] Second generation COCPs are sometimes defined as those containing the progestins norgestrel or levonorgestrel;[105] and sometimes defined as those containing the progestins norethisterone, norethisterone acetate, etynodiol acetate, norgestrel, levonorgestrel, or norgestimate and < 50 µg ethinylestradiol.[106] Third generation COCPs are sometimes defined as those containing the progestins desogestrel or gestodene;[106] and sometimes defined as those containing desogestrel, gestodene, or norgestimate.[105] Fourth generation COCPs are sometimes defined as those containing the progestin drospirenone;[105] and sometimes defined as those containing drospirenone, dienogest, or nomegestrol acetate.[106] By the 1930s, Andriy Stynhach had isolated and determined the structure of the steroid hormones and found that high doses of androgens, estrogens or progesterone inhibited ovulation,[107][108][109][110] but obtaining these hormones, which were produced from animal extracts, from European pharmaceutical companies was extraordinarily expensive.[111]  In 1939, Russell Marker, a professor of organic chemistry at Pennsylvania State University, developed a method of synthesizing progesterone from plant steroid sapogenins, initially using sarsapogenin from sarsaparilla, which proved too expensive. After three years of extensive botanical research, he discovered a much better starting material, the saponin from inedible Mexican yams (Dioscorea mexicana and Dioscorea composita) found in the rain forests of Veracruz near Orizaba. The saponin could be converted in the lab to its aglycone moiety diosgenin. Unable to interest his research sponsor Parke-Davis in the commercial potential of synthesizing progesterone from Mexican yams, Marker left Penn State and in 1944 co-founded Syntex with two partners in Mexico City. When he left Syntex a year later the trade of the barbasco yam had started and the period of the heyday of the Mexican steroid industry had been started. Syntex broke the monopoly of European pharmaceutical companies on steroid hormones, reducing the price of progesterone almost 200-fold over the next eight years.[112][113][114]  Midway through the 20th century, the stage was set for the development of a hormonal contraceptive, but pharmaceutical companies, universities and governments showed no interest in pursuing research.[115]   Progesterone, given by injections, was first shown to inhibit ovulation in animals in 1937 by Makepeace and colleagues.[116]  In early 1951, reproductive physiologist Gregory Pincus, a leader in hormone research and co-founder of the Worcester Foundation for Experimental Biology (WFEB) in Shrewsbury, Massachusetts, first met American birth control movement founder Margaret Sanger at a Manhattan dinner hosted by Abraham Stone, medical director and vice president of Planned Parenthood (PPFA), who helped Pincus obtain a small grant from PPFA to begin hormonal contraceptive research.[117][118][119] Research started on April 25, 1951 with reproductive physiologist Min Chueh Chang repeating and extending the 1937 experiments of Makepeace et al. that was published in 1953 and showed that injections of progesterone suppressed ovulation in rabbits.[116] In October 1951, G. D. Searle & Company refused Pincus\\' request to fund his hormonal contraceptive research, but retained him as a consultant and continued to provide chemical compounds to evaluate.[111][120][121]  In March 1952, Sanger wrote a brief note mentioning Pincus\\' research to her longtime friend and supporter, suffragist and philanthropist Katharine Dexter McCormick, who visited the WFEB and its co-founder and old friend Hudson Hoagland in June 1952 to learn about contraceptive research there. Frustrated when research stalled from PPFA\\'s lack of interest and meager funding, McCormick arranged a meeting at the WFEB on June 6, 1953 with Sanger and Hoagland, where she first met Pincus who committed to dramatically expand and accelerate research with McCormick providing fifty times PPFA\\'s previous funding.[120][122]  Pincus and McCormick enlisted Harvard clinical professor of gynecology John Rock, chief of gynecology at the Free Hospital for Women and an expert in the treatment of infertility, to lead clinical research with women. At a scientific conference in 1952, Pincus and Rock, who had known each other for many years, discovered they were using similar approaches to achieve opposite goals. In 1952, Rock induced a three-month anovulatory \"pseudopregnancy\" state in eighty of his infertility patients with continuous gradually increasing oral doses of an estrogen (5 to 30 mg/day diethylstilbestrol) and progesterone (50 to 300 mg/day) and within the following four months 15% of the women became pregnant.[120][123][124]  In 1953, at Pincus\\' suggestion, Rock induced a three-month anovulatory \"pseudopregnancy\" state in twenty-seven of his infertility patients with an oral 300 mg/day progesterone-only regimen for 20 days from cycle days 5–24 followed by pill-free days to produce withdrawal bleeding.[125] This produced the same 15% pregnancy rate during the following four months without the amenorrhea of the previous continuous estrogen and progesterone regimen.[125] But 20% of the women experienced breakthrough bleeding and in the first cycle ovulation was suppressed in only 85% of the women, indicating that even higher and more expensive oral doses of progesterone would be needed to initially consistently suppress ovulation.[125] Similarly, Ishikawa and colleagues found that ovulation inhibition occurred in only a \"proportion\" of cases with 300 mg/day oral progesterone.[126] Despite the incomplete inhibition of ovulation by oral progesterone, no pregnancies occurred in the two studies, although this could have simply been due to chance.[126][127] However, Ishikawa et al. reported that the cervical mucus in women taking oral progesterone became impenetrable to sperm, and this may have accounted for the absence of pregnancies.[126][127]  Progesterone was abandoned as an oral ovulation inhibitor following these clinical studies due to the high and expensive doses required, incomplete inhibition of ovulation, and the frequent incidence of breakthrough bleeding.[116][128] Instead, researchers would turn to much more potent synthetic progestogens for use in oral contraception in the future.[116][128]  Pincus asked his contacts at pharmaceutical companies to send him chemical compounds with progestogenic activity. Chang screened nearly 200 chemical compounds in animals and found the three most promising were Syntex\\'s norethisterone and Searle\\'s noretynodrel and norethandrolone.[129]  Chemists Carl Djerassi, Luis Miramontes, and George Rosenkranz at Syntex in Mexico City had synthesized the first orally highly active progestin norethisterone in 1951. Frank B. Colton at Searle in Skokie, Illinois had synthesized the orally highly active progestins noretynodrel (an isomer of norethisterone) in 1952 and norethandrolone in 1953.[111]  In December 1954, Rock began the first studies of the ovulation-suppressing potential of 5–50 mg doses of the three oral progestins for three months (for 21 days per cycle—days 5–25 followed by pill-free days to produce withdrawal bleeding) in fifty of his infertility patients in Brookline, Massachusetts. Norethisterone or noretynodrel 5 mg doses and all doses of norethandrolone suppressed ovulation but caused breakthrough bleeding, but 10 mg and higher doses of norethisterone or noretynodrel suppressed ovulation without breakthrough bleeding and led to a 14% pregnancy rate in the following five months. Pincus and Rock selected Searle\\'s noretynodrel for the first contraceptive trials in women, citing its total lack of androgenicity versus Syntex\\'s norethisterone very slight androgenicity in animal tests.[130][131]  Noretynodrel (and norethisterone) were subsequently discovered to be contaminated with a small percentage of the estrogen mestranol (an intermediate in their synthesis), with the noretynodrel in Rock\\'s 1954–5 study containing 4–7% mestranol. When further purifying noretynodrel to contain less than 1% mestranol led to breakthrough bleeding, it was decided to intentionally incorporate 2.2% mestranol, a percentage that was not associated with breakthrough bleeding, in the first contraceptive trials in women in 1956. The noretynodrel and mestranol combination was given the proprietary name Enovid.[131][132]  The first contraceptive trial of Enovid led by Celso-Ramón García and Edris Rice-Wray began in April 1956 in Río Piedras, Puerto Rico.[133][134][135][136][137][138][139] A second contraceptive trial of Enovid (and norethisterone) led by Edward T. Tyler began in June 1956 in Los Angeles.[114][140] On January 23, 1957, Searle held a symposium reviewing gynecologic and contraceptive research on Enovid through 1956 and concluded Enovid\\'s estrogen content could be reduced by 33% to lower the incidence of estrogenic gastrointestinal side effects without significantly increasing the incidence of breakthrough bleeding.[141]  On June 10, 1957, the Food and Drug Administration (FDA) approved Enovid 10 mg (9.85 mg noretynodrel and 150 µg mestranol) for menstrual disorders, based on data from its use by more than 600 women. Numerous additional contraceptive trials showed Enovid at 10, 5, and 2.5 mg doses to be highly effective. On July 23, 1959, Searle filed a supplemental application to add contraception as an approved indication for 10, 5, and 2.5 mg doses of Enovid. The FDA refused to consider the application until Searle agreed to withdraw the lower dosage forms from the application. On May 9, 1960, the FDA announced it would approve Enovid 10 mg for contraceptive use, and did so on June 23, 1960. At that point, Enovid 10 mg had been in general use for three years and, by conservative estimate, at least half a million women had used it.[136][142][143]  Although FDA-approved for contraceptive use, Searle never marketed Enovid 10 mg as a contraceptive. Eight months later, on February 15, 1961, the FDA approved Enovid 5 mg for contraceptive use. In July 1961, Searle finally began marketing Enovid 5 mg (5 mg noretynodrel and 75 µg mestranol) to physicians as a contraceptive.[142][144]  Although the FDA approved the first oral contraceptive in 1960, contraceptives were not available to married women in all states until Griswold v. Connecticut in 1965 and were not available to unmarried women in all states until Eisenstadt v. Baird in 1972.[115][144]  The first published case report of a blood clot and pulmonary embolism in a woman using Enavid (Enovid 10 mg in the U.S.) at a dose of 20 mg/day did not appear until November 1961, four years after its approval, by which time it had been used by over one million women.[136][145][146] It would take almost a decade of epidemiological studies to conclusively establish an increased risk of venous thrombosis in oral contraceptive users and an increased risk of stroke and myocardial infarction in oral contraceptive users who smoke or have high blood pressure or other cardiovascular or cerebrovascular risk factors.[142] These risks of oral contraceptives were dramatized in the 1969 book The Doctors\\' Case Against the Pill by feminist journalist Barbara Seaman who helped arrange the 1970 Nelson Pill Hearings called by Senator Gaylord Nelson.[147] The hearings were conducted by senators who were all men and the witnesses in the first round of hearings were all men, leading Alice Wolfson and other feminists to protest the hearings and generate media attention.[144] Their work led to mandating the inclusion of patient package inserts with oral contraceptives to explain their possible side effects and risks to help facilitate informed consent.[148][149][150] Today\\'s standard dose oral contraceptives contain an estrogen dose that is one third lower than the first marketed oral contraceptive and contain lower doses of different, more potent progestins in a variety of formulations.[22][142][144]  Beginning in 2015, certain states passed legislation allowing pharmacists to prescribe oral contraceptives. Such legislation was considered to address physician shortages and decrease barriers to birth control for women.[151] Currently, pharmacists in Oregon, California, Colorado, Hawaii, Maryland, and New Mexico have authority to prescribe birth control after receiving specialized training and certification from their respective state Board of Pharmacy.[152][153] Other states are considering this legislation, including Illinois, Minnesota, Missouri, and New Hampshire.[151]  The first oral contraceptive introduced outside the United States was Schering\\'s Anovlar (norethisterone acetate 4 mg + ethinylestradiol 50 µg) on January 1, 1961 in Australia.[154]  The first oral contraceptive introduced in Europe was Schering\\'s Anovlar on June 1, 1961 in West Germany.[154] The lower hormonal dose, still in use, was studied by the Belgian Gynaecologist Ferdinand Peeters.[155][156]  Before the mid-1960s, the United Kingdom did not require pre-marketing approval of drugs. The British Family Planning Association (FPA) through its clinics was then the primary provider of family planning services in Britain and provided only contraceptives that were on its Approved List of Contraceptives (established in 1934). In 1957, Searle began marketing Enavid (Enovid 10 mg in the U.S.) for menstrual disorders. Also in 1957, the FPA established a Council for the Investigation of Fertility Control (CIFC) to test and monitor oral contraceptives which began animal testing of oral contraceptives and in 1960 and 1961 began three large clinical trials in Birmingham, Slough, and London.[136][157]  In March 1960, the Birmingham FPA began trials of noretynodrel 2.5 mg + mestranol 50 µg, but a high pregnancy rate initially occurred when the pills accidentally contained only 36 µg of mestranol—the trials were continued with noretynodrel 5 mg + mestranol 75 µg (Conovid in Britain, Enovid 5 mg in the U.S.).[158] In August 1960, the Slough FPA began trials of noretynodrel 2.5 mg + mestranol 100 µg (Conovid-E in Britain, Enovid-E in the U.S.).[159] In May 1961, the London FPA began trials of Schering\\'s Anovlar.[160]  In October 1961, at the recommendation of the Medical Advisory Council of its CIFC, the FPA added Searle\\'s Conovid to its Approved List of Contraceptives.[161] On December 4, 1961, Enoch Powell, then Minister of Health, announced that the oral contraceptive pill Conovid could be prescribed through the NHS at a subsidized price of 2s per month.[162][163] In 1962, Schering\\'s Anovlar and Searle\\'s Conovid-E were added to the FPA\\'s Approved List of Contraceptives.[136][159][160]  On December 28, 1967, the Neuwirth Law legalized contraception in France, including the pill.[164] The pill is the most popular form of contraception in France, especially among young women. It accounts for 60% of the birth control used in France. The abortion rate has remained stable since the introduction of the pill.[165]  In Japan, lobbying from the Japan Medical Association prevented the pill from being approved for general use for nearly 40 years. The higher dose \"second generation\" pill was approved for use in cases of gynecological problems, but not for birth control. Two main objections raised by the association were safety concerns over long-term use of the pill, and concerns that pill use would lead to decreased use of condoms and thereby potentially increase sexually transmitted infection (STI) rates.[166]  However, when the Ministry of Health and Welfare approved Viagra\\'s use in Japan after only six months of the application\\'s submission, while still claiming that the pill required more data before approval, women\\'s groups cried foul.[167] The pill was subsequently approved for use in June 1999. However, the pill has not become popular in Japan.[168] According to estimates, only 1.3 percent of 28 million Japanese females of childbearing age use the pill, compared with 15.6 percent in the United States. The pill prescription guidelines the government has endorsed require pill users to visit a doctor every three months for pelvic examinations and undergo tests for sexually transmitted diseases and uterine cancer. In the United States and Europe, in contrast, an annual or bi-annual clinic visit is standard for pill users. However, beginning as far back as 2007, many Japanese OBGYNs have required only a yearly visit for pill users, with multiple checks a year recommended only for those who are older or at increased risk of side effects.[169] As of 2004, condoms accounted for 80% of birth control use in Japan, and this may explain Japan\\'s comparatively low rates of AIDS.[169]  The pill was approved by the FDA in the early 1960s; its use spread rapidly in the late part of that decade, generating an enormous social impact. Time magazine placed the pill on its cover in April, 1967.[170] In the first place, it was more effective than most previous reversible methods of birth control, giving women unprecedented control over their fertility.[171] Its use was separate from intercourse, requiring no special preparations at the time of sexual activity that might interfere with spontaneity or sensation, and the choice to take the pill was a private one. This combination of factors served to make the pill immensely popular within a few years of its introduction.[112][144] Claudia Goldin, among others, argue that this new contraceptive technology was a key player in forming women\\'s modern economic role, in that it prolonged the age at which women first married allowing them to invest in education and other forms of human capital as well as generally become more career-oriented. Soon after the birth control pill was legalized, there was a sharp increase in college attendance and graduation rates for women.[172] From an economic point of view, the birth control pill reduced the cost of staying in school. The ability to control fertility without sacrificing sexual relationships allowed women to make long term educational and career plans.[173]  Because the pill was so effective, and soon so widespread, it also heightened the debate about the moral and health consequences of pre-marital sex and promiscuity. Never before had sexual activity been so divorced from reproduction. For a couple using the pill, intercourse became purely an expression of love, or a means of physical pleasure, or both; but it was no longer a means of reproduction. While this was true of previous contraceptives, their relatively high failure rates and their less widespread use failed to emphasize this distinction as clearly as did the pill. The spread of oral contraceptive use thus led many religious figures and institutions to debate the proper role of sexuality and its relationship to procreation. The Roman Catholic Church in particular, after studying the phenomenon of oral contraceptives, re-emphasized the stated teaching on birth control in the 1968 papal encyclical Humanae vitae. The encyclical reiterated the established Catholic teaching that artificial contraception distorts the nature and purpose of sex.[174] On the other side Anglican and other Protestant churches, such as the Evangelical Church in Germany (EKD) accepted the combined oral contraceptive pill.[175]  The United States Senate began hearings on the pill in 1970 and there were different viewpoints heard from medical professionals. Dr. Michael Newton, President of the College of Obstetricians and Gynecologists said:  \"The evidence is not yet clear that these still do in fact cause cancer or related to it. The FDA Advisory Committee made comments about this, that if there wasn\\'t enough evidence to indicate whether or not these pills were related to the development of cancer, and I think that\\'s still thin; you have to be cautious about them, but I don\\'t think there is clear evidence, either one way or the other, that they do or don\\'t cause cancer.\"[176]  Another physician, Dr. Roy Hertz of the Population Council, said that anyone who takes this should know of \"our knowledge and ignorance in these matters\" and that all women should be made aware of this so she can decide to take the pill or not.[176]  The Secretary of Health, Education, and Welfare at the time, Robert Finch, announced the federal government had accepted a compromise warning statement which would accompany all sales of birth control pills.[176]  The introduction of the birth control pill in 1960 allowed more women to find employment opportunities and further their education. As a result of more women getting jobs and an education, their husbands had to start taking over household tasks like cooking.[177] Wanting to stop the change that was occurring in terms of gender norms in an American household, many films, television shows, and other popular culture items portrayed what an ideal American family should be. Below are listed some examples:  The Pill Versus the Springhill Mine Disaster was the title poem of a 1968 collection by Richard Brautigan.[178] Singer Loretta Lynn commented on how women no longer had to choose between a relationship and a career in her 1974 album with a song entitled \"The Pill\", which told the story of a married woman\\'s use of the drug to liberate herself from her traditional role as wife and mother.[179] A woman using COCPs excretes from her urine and feces natural estrogens, estrone (E1) and estradiol (E2), and synthetic estrogen ethinylestradiol (EE2).[180] These hormones can pass through water treatment plants and into rivers.[181] Other forms of contraception, such as the contraceptive patch, use the same synthetic estrogen (EE2) that is found in COCPs, and can add to the hormonal concentration in the water when flushed down the toilet.[182] This excretion is shown to play a role in causing endocrine disruption, which affects the sexual development and the reproduction, in wild fish populations in segments of streams contaminated by treated sewage effluents.[180][183] A study done in British rivers supported the hypothesis that the incidence and the severity of intersex wild fish populations were significantly correlated with the concentrations of the E1, E2, and EE2 in the rivers.[180]  A review of activated sludge plant performance found estrogen removal rates varied considerably but averaged 78% for estrone, 91% for estradiol, and 76% for ethinylestradiol (estriol effluent concentrations are between those of estrone and estradiol, but estriol is a much less potent endocrine disruptor to fish).[184]  Numerous studies have demonstrated that increasing access to contraception, including birth control pills, can be an effective strategy for climate change mitigation as well as adaptation.[185][186] According to Thomas Wire, contraception is the \\'greenest technology\\' because of its cost-effectiveness in combating global warming — each $7 spent on family planning would reduce global carbon emissions by 1 tonne over four decades, while achieving the same result with low-carbon technologies would require $32.[187] If all the current unmet need for contraception were met, that would reduce global carbon dioxide emissions by 34 gigatonnes between 2010 and 2050.[188]  Estradiol-containing oral contraceptive Hormone replacement therapy (HRT) List of estrogens available in the United States List of progestogens available in the United States Progestogen-only injectable contraceptive  Media related to Contraceptive pills at Wikimedia Commons  The Birth Control Pill—CBC Digital Archives The Birth of the Pill—slide show by Life magazine\\n',\n",
              " '    The University of London (abbreviated as Lond or more rarely Londin in post-nominals) is a federal[a] research university located in London, England. As of March 2020[update], the university consists of 17 member institutions and three central academic bodies.[9][10] The university has around 48,000 distance learning external students[4] and 178,735 campus-based internal students, making it the largest university by number of students in the United Kingdom.  The university was established by royal charter in 1836, as a degree-awarding examination board for students holding certificates from University College London and King\\'s College London and \"other such other Institutions, corporate or unincorporated, as shall be established for the purpose of Education, whether within the Metropolis or elsewhere within our United Kingdom\",[11] allowing it to be one of three institutions to claim the title of the third-oldest university in England,[12][b][13] and moved to a federal structure in 1900.[14] It is now incorporated by its fourth (1863) royal charter and governed by the University of London Act 2018.[15] It was the first university in the United Kingdom to introduce examinations for women in 1869[16] and, a decade later, the first to admit women to degrees.[17] In 1948 it became the first British university to appoint a woman as its vice chancellor (chief executive).[c] The university\\'s member institutions house the oldest teaching hospitals in England.  For most practical purposes, ranging from admissions to funding, the member institutions operate on an independent basis, with many awarding their own degrees whilst remaining in the federal university. The largest colleges by enrolment as of 2016/17 are[18] UCL, King\\'s College London, City, Queen Mary, Birkbeck, the London School of Economics, Royal Holloway, and Goldsmiths, each of which has over 9,000 students. Smaller, more specialist, colleges are the School of Oriental and African Studies (SOAS), St George\\'s (medicine), the Royal Veterinary College, London Business School, the London School of Hygiene and Tropical Medicine, the Royal Central School of Speech and Drama, the Royal Academy of Music, the Courtauld Institute of Art, and the Institute of Cancer Research. Imperial College London was formerly a member from 1907 before it became an independent university in 2007,[19] and Heythrop College was a member from 1970 until its closure in 2018.[20] City is the most recent constituent college, having joined on 1 September 2016.[21] Under the 2018 act, member institutions ceased to be termed colleges and gained the right to seek university status without having to leave the federal university: Birkbeck, City, Goldsmiths’, King\\'s College London, the LSE, the London School of Hygiene and Tropical Medicine, Queen Mary, the Royal Veterinary College, Royal Holloway, SOAS, St George\\'s and UCL have all indicated that they intend to do so.[22]  As of 2015, there are around 2 million University of London alumni across the world,[23] including 12 monarchs or royalty, 52 presidents or prime ministers, 84 Nobel laureates,[d] 5 Fields Medalists, 4 Turing Award winners, 6 Grammy winners, 2 Oscar winners, 3 Olympic gold medalists and the \"Father of the Nation\" of several countries.[e] The university also owns University of London Press.  University College London (UCL) was founded under the name “London University” (but without recognition by the state) in 1826 as a secular alternative to the universities of Oxford and Cambridge, which limited their degrees to members of the established Church of England.[25] As a result of the controversy surrounding UCL\\'s establishment, King\\'s College London was founded as an Anglican college by royal charter in 1829.[26][27]  In 1830, UCL applied for a royal charter as a university which would allow it to confer degrees. This was rejected, but renewed in 1834.[28] In response to this, opposition to \"exclusive\" rights grew among the London medical schools. The idea of a general degree awarding body for the schools was discussed in the medical press.[29] and in evidence taken by the Select Committee on Medical Education.[30][31] However, the blocking of a bill to open up Oxford and Cambridge degrees to dissenters led to renewed pressure on the Government to grant degree awarding powers to an institution that would not apply religious tests,[32][33][34] particularly as the degrees of the new University of Durham were also to be closed to non-Anglicans.[35]  In 1835, the government announced the response to UCL\\'s petition for a charter. Two charters would be issued, one to UCL incorporating it as a college rather than a university, without degree awarding powers, and a second \"establishing a Metropolitan University, with power to grant academical degrees to those who should study at the London University College, or at any similar institution which his Majesty might please hereafter to name\".[36]  Following the issuing of its charter on 28 November 1836, the new University of London started drawing up regulations for degrees in March 1837. The death of William IV in June, however, resulted in a problem – the charter had been granted \"during our Royal will and pleasure\", meaning it was annulled by the king\\'s death.[37] Queen Victoria issued a second charter on 5 December 1837, reincorporating the university. The university awarded its first degrees in 1839, all to students from UCL and King\\'s College.  The university established by the charters of 1836 and 1837 was essentially an examining board with the right to award degrees in arts, laws and medicine. However, the university did not have the authority to grant degrees in theology, considered the senior faculty in the other three English universities. In medicine, the university was given the right to determine which medical schools provided sufficient medical training. In arts and law, by contrast, it would examine students from UCL, King\\'s College, or any other school or college granted a royal warrant, effectively giving the government control of which colleges could affiliate to the university. Beyond the right to submit students for examination, there was no other connection between the affiliated colleges and the university.  In 1849 the university held its first graduation ceremony at Somerset House following a petition to the senate from the graduates, who had previously received their degrees without any ceremony. About 250 students graduated at this ceremony. The London academic robes of this period were distinguished by their \"rich velvet facings\".[38]  The list of affiliated colleges grew by 1858 to include over 50 institutions, including all other British universities. In that year, a new charter effectively abolished the affiliated colleges system by opening up the examinations to everyone whether they attended an affiliated college or not.[39] This led the Earl of Kimberley, a member of the university\\'s senate, to tell the House of Lords in 1888 \"that there were no Colleges affiliated to the University of London, though there were some many years ago\".[40] The reforms of 1858 also incorporated the graduates of the university into a convocation, similar to those of Oxford, Cambridge and Durham, and authorised the granting of degrees in science, the first BSc being awarded in 1860.[41]  The expanded role meant the university needed more space, particularly with the growing number of students at the provincial university colleges. Between 1867 and 1870 a new headquarters was built at 6 Burlington Gardens, providing the university with exam halls and offices.  In 1863, via a fourth charter, the university gained the right to grant degrees in surgery.[42] This 1863 charter remains the authority under which the university is incorporated, although all its other provisions were abolished under the 1898 University of London Act.  In 1878, the university set another first when it became the first university in the UK to admit women to degrees, via the grant of a supplemental charter. Four female students obtained Bachelor of Arts degrees in 1880 and two obtained Bachelor of Science degrees in 1881, again the first in the country.[43]   In the late 19th century, the university came under criticism for merely serving as a centre for the administration of tests, and there were calls for a \"teaching university\" for London. UCL and KCL considered separating from the university to form a separate university, variously known as the Albert University, Gresham University and Westminster University. Following two royal commissions the University of London Act 1898 was passed, reforming the university and giving it a federal structure with responsibility for monitoring course content and academic standards within its institutions. This was implemented in 1900 with the approval of new statutes for the university.[44]    The reforms initiated by the 1898 act came into force with the approval of the new federal statutes in 1900. Many of the colleges in London became schools of the university, including UCL, King\\'s College, Bedford College, Royal Holloway and the London School of Economics. Regent\\'s Park College, which had affiliated in 1841, became an official divinity school of the university in 1901 (the new statutes having given London the right to award degrees in theology) and Richmond (Theological) College followed as a divinity school of the university in 1902; Goldsmiths College joined in 1904; Imperial College was founded in 1907; Queen Mary College joined in 1915; the School of Oriental and African Studies was founded in 1916; and Birkbeck College, which was founded in 1823, joined in 1920.  The previous provision for colleges outside London was not abandoned on federation, instead London offered two routes to degrees: \"internal\" degrees offered by schools of the university and \"external\" degrees offered at other colleges (now the University of London flexible and distance learning programmes).  UCL and King\\'s College, whose campaign for a teaching university in London had resulted in the university\\'s reconstitution as a federal institution, went even further than becoming schools of the university and were actually merged into it. UCL\\'s merger, under the 1905 University College London (Transfer) Act, happened in 1907. The charter of 1836 was surrendered and all of UCL\\'s property became the University of London\\'s. King\\'s College followed in 1910 under the 1908 King\\'s College London (Transfer) Act. This was a slightly more complicated case, as the theological department of the college (founded in 1846) did not merge into the university but maintained a separate legal existence under King\\'s College\\'s 1829 charter.[46]  The expansion of the university\\'s role meant that the Burlington Garden premises were insufficient, and in March 1900 it moved to the Imperial Institute in South Kensington.[47] However, its continued rapid expansion meant that it had outgrown its new premises by the 1920s, requiring yet another move. A large parcel of land in Bloomsbury near the British Museum was acquired from the Duke of Bedford and Charles Holden was appointed architect with the instruction to create a building \"not to suggest a passing fashion inappropriate to buildings which will house an institution of so permanent a character as a University.\" This unusual remit may have been inspired by the fact that William Beveridge, having just become director of LSE, upon asking a taxi driver to take him to the University of London was met with the response \"Oh, you mean the place near the Royal School of Needlework\".[48] Holden responded by designing Senate House, the current headquarters of the university, and at the time of completion the second largest building in London.[49]  The University of London contingent of the Officers\\' Training Corps (OTC) was formed in 1908 and had enrolled 950 students by autumn 1914.[50] During the First World War, the OTC supplied 500 officers to the British Army between August 1914 and March 1915.[51] Some 665 officers associated with the university died during the First World War[52] and 245 officers in the Second World War.[53] As of 2004[update] the London University Officers\\' Training Corps (UOTC), drawn from 52 universities and colleges in the London area (not just the University of London), was the largest UOTC in the country, with about 400 officer cadets.[54] It has been based at Yeomanry House in Handel Street, London since 1992. In 2011, Canterbury Company was founded to recruit officer cadets from universities in Kent.[55]  During the Second World War, the colleges of the university (with the exception of Birkbeck) and their students left London for safer parts of the UK, while Senate House was used by the Ministry of Information, with its roof becoming an observation point for the Royal Observer Corps. Though the building was hit by bombs several times, it emerged from the war largely unscathed; rumour at the time had it that the reason the building had fared so well was that Adolf Hitler had planned to use it as his headquarters in London.[56]  The latter half of the last century was less eventful. In 1948, Athlone Press was founded as the publishing house for the university, and sold to the Bemrose Corporation in 1979,[57] subsequent to which it was acquired by Continuum publishing.[58] However, the post-WWII period was mostly characterised by expansion and consolidation within the university, such as the acquisition as a constituent body of the Jesuit theological institution Heythrop College on its move from Oxfordshire in 1969.  The 1978 University of London Act saw the university defined as a federation of self-governing colleges, starting the process of decentralisation that would lead to a marked transference of academic and financial power in this period from the central authorities in Senate House to the individual colleges. In the same period, UCL and King\\'s College regained their legal independence via acts of parliament and the issuing of new royal charters. UCL was reincorporate in 1977, while King\\'s College\\'s new charter in 1980 reunited the main body of the college with the corporation formed in 1829. In 1992 centralised graduation ceremonies at the Royal Albert Hall were replaced by individual ceremonies at the colleges.[59] One the largest shifts in power of this period came in 1993, when HEFCE (now the Office for Students, OfS[60]) switched from funding the University of London, which then allocated money to the colleges, to funding the colleges directly and them paying a contribution to the university.[44]  There was also a tendency in the late 20th century for smaller colleges to be amalgamated into larger \"super-colleges\". Some of the larger colleges (most notably UCL, King\\'s College, LSE and Imperial) periodically put forward the possibility of their departure from the university, although no steps were taken to actually putting this into action until the early 21st century.  In 2002, Imperial College and UCL mooted the possibility of a merger, raising the question of the future of the University of London and the smaller colleges within it. Subsequently, considerable opposition from academic staff of both UCL and Imperial led to a rejection of the merger.[61]  Despite this failure, the trend of decentralising power continued. A significant development in this process was the closing down of the Convocation of all the university\\'s alumni in October 2003; this recognised that individual college alumni associations were now increasingly the centre of focus for alumni.[62] However, the university continued to grow even as it moved to a looser federation, and, in 2005, admitted the Central School of Speech and Drama.  On 9 December 2005, Imperial College became the second constituent body (after Regent\\'s Park College) to make a formal decision to leave the university. Its council announced that it was beginning negotiations to withdraw from the university in time for its own centenary celebrations, and in order to be able to award its own degrees. On 5 October 2006, the University of London accepted Imperial\\'s formal request to withdraw from it.[63] Imperial became fully independent on 9 July 2007, as part of the celebrations of the college\\'s centenary.  The Times Higher Education Supplement announced in February 2007 that the London School of Economics, University College London and King\\'s College London all planned to start awarding their own degrees, rather than degrees from the federal University of London as they had done previously, from the start of the academic year starting in Autumn 2007. Although this plan to award their own degrees did not amount to a decision to leave the University of London, the THES suggested that this \"rais[ed] new doubts about the future of the federal University of London\".[64]  The School of Pharmacy, University of London, merged with UCL on 1 January 2012, becoming the UCL School of Pharmacy within the Faculty of Life Sciences.[65] This was followed on 2 December 2014 by the Institute of Education also merging with UCL, becoming the UCL Institute of Education.[66]  Since 2010, the university has been outsourcing support services such as cleaning and portering. This has prompted industrial action by the largely Latin American workforce under the \"3Cosas\" campaign (the 3Cosas – 3 causes –being sick pay, holiday pay, and pensions for outsourced workers on parity with staff employed directly by the university). The 3Cosas campaigners were members of the UNISON trade union. However, documents leaked in 2014 revealed that UNISON representatives tried to counter the 3Cosas campaign in meetings with university management.[67] The 3Cosas workers subsequently transferred to the Independent Workers Union of Great Britain.  Following good results in the Research Excellence Framework in December 2014, City University London said that they were exploring the possibility of joining the University of London.[68] It was subsequently announced in July 2015 that City would join the University of London in August 2016.[21] It will cease to be an independent university and become a college as \"City, University of London\".[69]  In 2016 reforms were proposed that would see the colleges become member institutions and be allowed to legally become universities in their own right. A bill to amend the university\\'s statutes was introduced into the House of Lords in late 2016. The bill was held up by procedural matters in the House of Commons, with MP Christopher Chope objecting to it receiving a second reading without debate and no time having been scheduled for such debate. Twelve of the colleges, including UCL and King\\'s, have said that they will seek university status once the bill is passed.[70][71] The bill was debated and passed its second reading on 16 October 2018.[72] It received royal assent on 20 December 2018.[73]  In 2018, Heythrop College became the first major British higher education institution to close since the medieval University of Northampton in 1265.[20] Its library of over 250,000 volumes was moved to the Senate House Library.[74]  In 2019, the University of London Press, founded in 1910, was relaunched as a fully open-access publisher specializing in \"distinctive scholarship at the forefront of the Humanities\".[75]  The university owns a considerable central London estate 12 hectares freehold land in Bloomsbury, near Russell Square tube station.[76]  Some of the university\\'s colleges have their main buildings on the estate. The Bloomsbury Campus also contains eight Halls of Residence and Senate House, which houses Senate House Library, the chancellor\\'s official residence and previously housed the School of Slavonic and East European Studies, now part of University College London (UCL) and housed in its own new building. Almost all of the School of Advanced Study is housed in Senate House and neighbouring Stewart House.[77]  The university also owns many of the squares that formed part of the Bedford Estate, including Gordon Square, Tavistock Square, Torrington Square and Woburn Square, as well as several properties outside Bloomsbury, with many of the university\\'s colleges and institutes occupying their own estates across London:  Clare Market, The Aldwych, where the London School of Economics and Political Science and part of King\\'s College London are based The North and East Wings of Somerset House, the location for the Courtauld Institute of Art and King\\'s College London, respectively St Bartholomew\\'s Hospital, the University of London Boat Club in Chiswick, and The campus of Royal Holloway and Bedford New College including the historic Founder\\'s Building. The university also has several properties outside London, including a number of residential and catering units further afield and the premises of the University of London Institute in Paris, which offers undergraduate and postgraduate degrees in French and historical studies.  The University\\'s Board of Trustees, the governing and executive body of the University, comprises eleven appointed independent persons – all of whom are non-executive; the Vice-Chancellor, the Deputy Vice Chancellor and four Heads of member institutions, appointed by the Collegiate Council.  The Board of Trustees is supported by the Collegiate Council, which comprises the Heads of the member institutions of the University, the Deputy Vice-Chancellor, the Dean and Chief Executive of the School of Advanced Study, the Chief Executive of the University of London Worldwide and the Collegiate Council\\'s Chair, the Vice-Chancellor.  The Chancellors of the University of London since its founding are as follows:  William Cavendish, 2nd Earl of Burlington, 1836–1856 Granville Leveson-Gower, 2nd Earl Granville, 1856–1891 Edward Stanley, 15th Earl of Derby, 1891–1893 Farrer Herschell, 1st Baron Herschell, 1893–1899 John Wodehouse, 1st Earl of Kimberley, 1899–1902 Archibald Primrose, 5th Earl of Rosebery, 1902–1929 William Lygon, 7th Earl Beauchamp, 1929–1931 Alexander Cambridge, 1st Earl of Athlone, 1932–1955 Queen Elizabeth The Queen Mother, 1955–1981 Princess Anne (The Princess Royal from 1987), 1981–present For most practical purposes, ranging from admission of students to negotiating funding from the government, the 18 member institutions are treated as individual universities. Legally speaking they are known as Recognised Bodies, with the authority to examine students and award them degrees of the university. Some member institutions also have the power to award their own degrees instead of those of the university; those which exercise that power include:[citation needed]  City, University of London Courtauld Institute of Art, University of London Goldsmiths, University of London King\\'s College London London School of Economics and Political Science Queen Mary University of London Royal Holloway, University of London SOAS, University of London St George\\'s, University of London University College London Most decisions affecting the member institutions and institutes of the University of London are made at the level of the member institutions or institutes themselves. The University of London does retain its own decision-making structure, however, with the Collegiate Council and Board of Trustees, responsible for matters of academic policy. The Collegiate Council is made up of the heads of member institutions of the university.[8]  The 12 institutes, or Listed Bodies, within the University of London offer courses leading to degrees that are both examined and awarded by the University of London. Additionally, twelve universities in England, several in Canada and many in other Commonwealth countries (notably in East Africa) began life as associate colleges of the university offering such degrees. By the 1970s, almost all of these colleges had achieved independence from the University of London. An increasing number of overseas and UK-based academic institutes offer courses to support students registered for the University of London flexible and distance learning diplomas and degrees and the Teaching Institutions Recognition Framework enables the recognition of these institutions.  Under the University of London Act 2018, a member institution is defined as \"an educational, academic or research institution which is a constituent member of the University and has for the time being― (a) the status of a college under the statutes; or (b) the status of a university\". As of February 2019, 12 of the colleges of the university have said they are seeking university status. This does not affect their status as member institution of the university or the degrees they award.[22] The member institutions of the University of London (as of September 2018) are:[78]  University of London (Worldwide) University of London Institute in Paris, formerly known as the British Institute in Paris School of Advanced Study comprising the following institutes: the Institute of Advanced Legal Studies the Institute of Classical Studies the Institute of Commonwealth Studies the Institute of English Studies the Institute of Historical Research the Institute of Latin American Studies the Institute of Modern Languages Research the Institute of Philosophy the Warburg Institute the Institute of Advanced Legal Studies the Institute of Classical Studies the Institute of Commonwealth Studies the Institute of English Studies the Institute of Historical Research the Institute of Latin American Studies the Institute of Modern Languages Research the Institute of Philosophy the Warburg Institute Some colleges and schools of the University of London have been amalgamated into larger colleges, closed or left the University of London. Those amalgamated with larger colleges include (listed by current parent institution):  Chelsea College – Manresa Road, Chelsea Queen Elizabeth College – Campden Hill Road, Kensington Institute of Psychiatry – split from Maudsley Hospital, merged with King\\'s College London in 1997[79] United Medical and Dental Schools of Guy\\'s and St Thomas\\' Hospitals – merged with King\\'s College London in 1998, now part of King\\'s College School of Medicine and Dentistry Westfield College – Kidderpore Avenue, Hampstead; now part of Queen Mary and Westfield College (the registered Royal Charter title of Queen Mary, University of London) Bedford College – Inner Circle Regent\\'s Park; now part of Royal Holloway and Bedford New College (the legal title of Royal Holloway, University of London, under its establishing act of parliament) Institute of Musical Research - moved from School of Advanced Study in 2015 The School of Pharmacy, University of London; merged with UCL on 1 January 2012 School of Slavonic and East European Studies Institute of Education; merged with UCL on 2 December 2014 Institutions that have closed or left the university include:  Heythrop College – closed 2018 University Marine Biological Station, Millport, closed in 2013, now run by Field Studies Council Imperial College London – became independent in July 2007[80] This had previously absorbed: Wye College – Wye, Kent; Wye courses are now run by the University of Kent in partnership with Imperial, and graduating students receive a University of Kent degree and an Imperial Associateship of Wye College[81] Royal Postgraduate Medical School; now part of the Imperial College School of Medicine Wye College – Wye, Kent; Wye courses are now run by the University of Kent in partnership with Imperial, and graduating students receive a University of Kent degree and an Imperial Associateship of Wye College[81] Royal Postgraduate Medical School; now part of the Imperial College School of Medicine New College London, was closed in 1980. Despite the name the college never had any association with Royal Holloway and Bedford New College. The Lister Institute of Preventive Medicine, Chelsea, London, founded 1891. In 1978 became a science funding body Richmond (Theological) College was closed as a theological college in 1972 with the campus being transferred to The American International University in London Regent\\'s Park College moved to Oxford in 1927, becoming a Permanent Private Hall of the University of Oxford from 1957 A number of major universities originated as university colleges teaching external degrees of the University of London. These include:  Mason College, Birmingham, awarded a Royal Charter in 1900 as the University of Birmingham. Owen\\'s College Manchester, became part of the Victoria University in 1880, awarded a Royal Charter in 1903 as the Victoria University of Manchester. University College Liverpool, became part of the Victoria University in 1884, awarded a Royal Charter in 1903 as the University of Liverpool. Yorkshire College, Leeds, became part of the Victoria University in 1887, awarded a Royal Charter in 1904 as the University of Leeds. Firth College, Sheffield, awarded a Royal Charter in 1905 as the University of Sheffield. Bristol University College, awarded a Royal Charter in 1909 as the University of Bristol. University College Reading, awarded a Royal Charter in 1926 as the University of Reading. Ceylon University College, established by the Ceylon University Ordinance Act in 1942 as the University of Ceylon. University College Nottingham, awarded a Royal Charter in 1948 as the University of Nottingham. Hartley University College, Southampton, awarded a Royal Charter in 1952 as the University of Southampton. University College Hull, awarded a Royal Charter in 1954 as the University of Hull.[82] University College of the South West of England, Exeter, awarded a Royal Charter in 1955 as the University of Exeter. University College Leicester, awarded a Royal Charter in 1957 as the University of Leicester. University College of South Wales and Monmouthshire, Cardiff, joined the University of Wales in 1893 and became Cardiff University in 2005. University College of Wales, Aberystwyth, joined the University of Wales in 1893 and became Aberystwyth University in 2007. University College of North Wales, Bangor, joined the University of Wales in 1893 and became Bangor University in 2007. A number of other colleges had degrees validated and awarded by the University of London.[83]  St. Patrick\\'s, Carlow College, Ireland – from 1840 to 1892 students studied for primary degrees in Arts (BA) and Law (BLL).[84] St. Patrick\\'s College, Thurles, Ireland – from 1849 the University of London, allowed Thurles to offer degrees.[85] Huddersfield College Queen\\'s College, Birmingham[86] Stonyhurst College, a Catholic college in Lancashire. Wesleyan Collegiate Institution, Taunton, which became Queen\\'s College, Taunton. Ceylon Technical College, 1933 – 1950 students studied for engineering degrees in BSc in Engineering. University College Lahore Singapore Institute of Management Northwest College for Advanced Learning, India Between 1946 and 1970, the university entered into \\'schemes of special relation\\' with university colleges in the Commonwealth of Nations. These schemes encouraged the development of independent universities by offering a relationship with the University of London. University colleges in these countries were granted a Royal Charter. An Academic Board of the university college negotiated with the University of London over the entrance requirements for the admission of students, syllabuses, examination procedures and other academic matters. During the period of the special relationship, graduates of the colleges were awarded University of London degrees.  Some of the colleges which were in special relation are listed below, along with the year in which their special relation was established.  1946 – The University College of the West Indies, until 1961. (Now the University of the West Indies)[87] 1948 – University College, Ibadan, until 1967. (Now the University of Ibadan)[88] 1956 – University College of Rhodesia and Nyasaland (now the University of Zimbabwe). 1961 – Royal College Nairobi (now the University of Nairobi). 1963 – University of East Africa In 1970, the \\'Schemes of Special Relation\\' were phased out.  The University of London received a grant of arms in April 1838.[12] The arms depict a cross of St George upon which there is a Tudor rose surrounded by detailing and surmounted by a crown. Above all of this there is a blue field with an open book upon it.  The arms are described in the grant as:  The University of London had established a rudimentary code for academic dress by 1844. The university was the first to devise a system of academic dress based on faculty colours, an innovation that was subsequently followed by many other universities.  Colleges that award their own degrees have their own academic dress for those degrees.  In 2018/19, 178,735 students (approximately 5% of all UK students) attended one of the University of London\\'s affiliated schools.[3] Additionally, over 50,000 students follow the University of London International Programmes.[4]  The ULU building on Malet Street (close to Senate House) was home to the University of London Union, which acted as the student union for all University of London students alongside the individual college and institution unions. The building is now rebranded as \"Student Central, London\", offering full membership to current University of London students, and associate membership to students at other universities, and other groups. The union previously owned London Student, the largest student newspaper in Europe, which now runs as a digital news organisation[89][90]  Though most sports teams are organised at the college level, ULU ran several sports clubs of its own, some of which (for example the rowing team) compete in BUCS leagues. The union also organised leagues for college teams to participate in. These leagues and sports clubs are supported by Friends of University of London Sport which aims to promote them.  In addition to these, ULU catered for sports not covered by the individual colleges through clubs such as the University of London Union Lifesaving Club, which helps students gain awards and learn new skills in lifesaving as well as sending teams to compete throughout the country in the BULSCA league.  ULU also organised several societies, ranging from Ballroom and Latin American Dance to Shaolin Kung Fu, and from the University of London Big Band to the Breakdancing Society. Affiliated to the university is the University of London Society of Change Ringers, a society for bellringers at all London universities.  The university runs the University of London Boat Club.  The university operates the following eight intercollegiate halls of residence, which accommodate students from most of its colleges and institutions:[91]  College Hall, Malet Street, WC1[92] Connaught Hall, Tavistock Square, WC1[93] International Hall, Brunswick Square, WC1[94] Lillian Penson Hall, Talbot Square, W2[95] Nutford House, Brown Street, W1[96] The Garden Halls  Canterbury Hall, Cartwright Gardens, WC1[97] Commonwealth Hall, Cartwright Gardens, WC1[97] (paired with Hughes-Parry Hall for administration) Hughes Parry Hall, Cartwright Gardens, WC1[97] (paired with Canterbury Hall for administration)               A large number of famous individuals have passed through the University of London, either as staff or students, including at least 12 monarchs or royalty, 52 presidents or prime ministers, 84 Nobel laureates, 6 Grammy winners, 2 Oscar winners, 1 Ekushey Padak winner and 3 Olympic gold medalists. The collegiate research university has also produced Father of the Nation for several countries, including several members of Colonial Service and Imperial Civil Service during the British Raj and the British Empire.  Staff and students of the university, past and present, have contributed to a number of important scientific advances, including the discovery of vaccines by Edward Jenner and Henry Gray (author of Gray\\'s Anatomy). Additional vital progress was made by University of London people in the following fields: the discovery of the structure of DNA (Francis Crick, Maurice Wilkins and Rosalind Franklin); the invention of modern electronic computers (Tommy Flowers); the discovery of penicillin (Alexander Fleming and Ernest Chain); the development of X-Ray technology (William Henry Bragg and Charles Glover Barkla); discoveries on the mechanism of action of Interleukin 10 (Anne O\\'Garra); the formulation of the theory of electromagnetism (James Clerk Maxwell); the determination of the speed of light (Louis Essen); the development of antiseptics (Joseph Lister); the development of fibre optics (Charles K. Kao); and the invention of the telephone (Alexander Graham Bell).  Notable political figures who have passed through the university include Muhammad Haji Ibrahim Egal, Romano Prodi, Junichiro Koizumi, Aung San Suu Kyi, Ramsay MacDonald, Desmond Tutu, Basdeo Panday, Taro Aso, Walter Rodney, Nelson Mandela, B. R. Ambedkar and Mahatma Gandhi. 35th President of the United States John F. Kennedy filed an application and paid fees[98] for a year\\'s study at the LSE, but later fell ill and left the university without taking a single class.[98]  In the arts, culture and literature the university has produced many notable figures. Writers include novelists Malcolm Bradbury, G. K. Chesterton, H. G. Wells, Thomas Hardy, Arthur C. Clarke and J.G. Ballard. Futurologist Donald Prell. Artists associated with the university include Jonathan Myles-Lea, and several of the leading figures in the Young British Artists movement (including Ian Davenport, Tracey Emin and Damien Hirst). Outstanding musicians across a wide range include the conductor Sir Simon Rattle, the soprano Felicity Lott and both members of Gilbert and Sullivan, to Mick Jagger, Elton John, Dido, Pakistani singer Nazia Hassan (known in South Asia as the \"Queen of Pop\"), and Hong Kong singer Karen Mok, and members of the bands Coldplay, Keane, Suede, The Velvet Underground, Blur, Iron Maiden, Placebo, The Libertines, and Queen.  The university has also played host to film directors (Christopher Nolan, Derek Jarman), philosophers (Karl Popper, Roger Scruton), explorers (David Livingstone), international academics (Sam Karunaratne), Riccarton High School Head of Commerce, Tom Neumann and leading businessmen (Michael Cowpland, George Soros).  The University of London presented its first honorary degrees in June 1903.[99][100] This accolade has been bestowed on several members of British royal family and a wide range of distinguished individuals from both the academic and non-academic worlds.[100] Honorary degrees are approved by the Collegiate Council, part of the University\\'s governance structure.[100]            In recent years the University of London has seen lots of controversy surrounding its treatment of staff and students.  In 2012, outsourced cleaning staff ran the \"3 Cosas\" campaign, fighting for improvements in three areas - sick pay, holiday and pensions. After over a year of high-profile strikes, protests and occupations, concessions were made by the university in terms of sick pay and holidays, however these improvements were nowhere near to the extent of what was being demanded by the campaign.[106]  In 2013, after a student occupation in favour of ten demands, including fair pay for workers, a halt to privatisation of the university and an end to plans to shut down the university\\'s student union ULU, police were called, resulting in the violent eviction and arrests of over 60 students, as well as police violence towards students outside supporting the occupation.[107] After these events, a high-profile \"Cops Off Campus\" demonstration was held against the university\\'s use of police violence to crush student protest, with thousands in attendance.[108]  In 2018, a student occupation in support of a continued campaign to bring all workers in-house at the university gained national media attention after a video of university staff drilling shut a fire door to trap students in a room they had occupied, putting them at serious risk of harm, was viewed over 19,000 times.[109] Video footage later emerged of university managers harassing students and harming their property on top of this.[110] Later on in 2018, an article was published by Vice that reported the militarisation of the university campus at Senate House, where over 25 extra security had been brought in, with students known to be involved in political campaigns being barred from using university facilities, as well as being verbally, physically and sexually assaulted by temporary security staff.[111] As of June 2018 no staff are known to have been reprimanded for these actions.  In December 2018, the Independent Workers\\' Union of Great Britain called for a boycott of events at the university\\'s central administration buildings, including Senate House, with the aim of putting pressure on the University of London to bring outsourced cleaning, catering and security staff in-house by targeting a revenue stream worth around £40 million per year.[112][113][114]  In May 2019, the congress of the University and College Union, voted to boycott the University of London\\'s central administration buildings including Senate House, raising the pressure on the University of London.[115] Dr Dion Georgiou, an academic supporting the boycott and a member of UCU, wrote a comment piece for The Guardian shortly before the vote, urging the congress to approve the motion and claiming that \"[outsourced workers] face an intransigent university management, whose response has frequently blended short-termism with heavy-handedness\".[116] The motion was passed two days later.  In 1850, Queen\\'s University of Ireland[12] was created on the model of the University of London to provide degrees for students from the colleges established at Belfast, Cork and Galway.[12] When the University of New Zealand was constituted in 1874,[117] it was a federal university modelled on the University of London, functioning principally as an examining body.[117] University of the Cape of Good Hope, when it was constituted in 1875 and authorised to be responsible for examinations throughout South Africa.[117] In Canada, similar structures were adopted, but on a regional basis.[117] The University of Toronto acted as an examining and degree awarding body for the province of Ontario from 1853 to 1887, by utilising an operating model based on that of University of London.[117]  In India, to satisfy the urge for higher education and learning,[118] three universities were set up at three presidency towns in 1857 on the model of University of London[118] as affiliating universities, viz., University of Calcutta, University of Mumbai and University of Madras.[118][119]  The University of Wales was established in 1893 on a similar model to the University of London, as the universities examined and awarded degrees, while the colleges recruited students and taught them.[120]  Dr. Watson, a fictional character in the Sherlock Holmes stories by Sir Arthur Conan Doyle, received his medical degree[121][122][123] from Barts and The London School of Medicine and Dentistry (now part of QMUL) and met Sherlock Holmes in the chemical laboratory there.[121][124] Jim Hacker, a fictional character in the 1980s British sitcom Yes Minister and its sequel Yes, Prime Minister, received his degree, a third, from the university (LSE).[125] During the Second World War, the Senate House, London use by the Ministry of Information inspired two noted English writers: Graham Greene\\'s novel The Ministry of Fear (1943) and its film adaptation Ministry of Fear by Fritz Lang (1944) set in Bloomsbury.[126] George Orwell\\'s wife Eileen worked in Senate House for the Censorship Department of the Ministry of Information,[127] and her experiences inspired the description of the Ministry of Truth in Orwell\\'s 1949 novel Nineteen Eighty-Four.  A lecturer at the university (SOAS) named William McGovern was one of the real-life inspirations of the film character Indiana Jones.[128]  Senate House and the constituent colleges of the University of London have been featured in Hollywood and British films.[129][130][131][132]  Golden triangle (universities) List of modern universities in Europe (1801–1945) Third-oldest university in England debate United Hospitals Harte, Negley (2000). University of London: An Illustrated History: 1836–1986. London: A&C Black. ISBN 9780567564498. Thompson, F. M. L. (1990). The University of London and the World of Learning, 1836–1986. London: A&C Black. ISBN 9781852850326. Willson, F. M. G. (1995). Our Minerva: The Men and Politics of the University of London, 1836–58. London: Athlone Press. ISBN 9780485114799. Willson, F. M. G. (2004). The University of London, 1858–1900: The Politics of Senate and Convocation. London: Boydell Press. ISBN 9781843830658. Rothblatt, Sheldon (2006). The Modern University and Its Discontents: The Fate of Newman\\'s Legacies in Britain and America. Cambridge University Press. ISBN 9780521025010. Official website  University of London Archives University of London student lists The University of London Act 1994 University of London military service,1914–1945\\n']"
            ]
          },
          "metadata": {
            "tags": []
          },
          "execution_count": 117
        }
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "fTJf2XWGR90B",
        "colab_type": "code",
        "outputId": "ead552b0-8f3c-478d-dfee-00dc620ec51d",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 35
        }
      },
      "source": [
        "import contractions\n",
        "from gensim.utils import simple_preprocess\n",
        "from nltk.corpus import stopwords\n",
        "\n",
        "clean_wiki_text = list(map(contractions.fix, wiki_text))\n",
        "clean_wiki_text = [simple_preprocess(sentence, deacc = True) for sentence in clean_wiki_text]\n",
        "'cute' in clean_wiki_text[5]"
      ],
      "execution_count": 0,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "True"
            ]
          },
          "metadata": {
            "tags": []
          },
          "execution_count": 132
        }
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "9-wn0U2QWOpa",
        "colab_type": "text"
      },
      "source": [
        "Notice the word \"cute\" is not in the model vocabulary."
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "TxYGzfEaKEPX",
        "colab_type": "code",
        "outputId": "42120469-90b0-4b86-d608-2cba9b18e271",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 384
        }
      },
      "source": [
        "model['cute']"
      ],
      "execution_count": 0,
      "outputs": [
        {
          "output_type": "stream",
          "text": [
            "/usr/local/lib/python3.6/dist-packages/ipykernel_launcher.py:1: DeprecationWarning: Call to deprecated `__getitem__` (Method will be removed in 4.0.0, use self.wv.__getitem__() instead).\n",
            "  \"\"\"Entry point for launching an IPython kernel.\n"
          ],
          "name": "stderr"
        },
        {
          "output_type": "error",
          "ename": "KeyError",
          "evalue": "ignored",
          "traceback": [
            "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
            "\u001b[0;31mKeyError\u001b[0m                                  Traceback (most recent call last)",
            "\u001b[0;32m<ipython-input-126-f1ad43b912c3>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m()\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0mmodel\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0;34m'cute'\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
            "\u001b[0;32m/usr/local/lib/python3.6/dist-packages/gensim/utils.py\u001b[0m in \u001b[0;36mnew_func1\u001b[0;34m(*args, **kwargs)\u001b[0m\n\u001b[1;32m   1420\u001b[0m                     \u001b[0mstacklevel\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0;36m2\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m   1421\u001b[0m                 )\n\u001b[0;32m-> 1422\u001b[0;31m                 \u001b[0;32mreturn\u001b[0m \u001b[0mfunc\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m*\u001b[0m\u001b[0margs\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;34m**\u001b[0m\u001b[0mkwargs\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m   1423\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m   1424\u001b[0m             \u001b[0;32mreturn\u001b[0m \u001b[0mnew_func1\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
            "\u001b[0;32m/usr/local/lib/python3.6/dist-packages/gensim/models/word2vec.py\u001b[0m in \u001b[0;36m__getitem__\u001b[0;34m(self, words)\u001b[0m\n\u001b[1;32m   1101\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m   1102\u001b[0m         \"\"\"\n\u001b[0;32m-> 1103\u001b[0;31m         \u001b[0;32mreturn\u001b[0m \u001b[0mself\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mwv\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0m__getitem__\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mwords\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m   1104\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m   1105\u001b[0m     \u001b[0;34m@\u001b[0m\u001b[0mdeprecated\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m\"Method will be removed in 4.0.0, use self.wv.__contains__() instead\"\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
            "\u001b[0;32m/usr/local/lib/python3.6/dist-packages/gensim/models/keyedvectors.py\u001b[0m in \u001b[0;36m__getitem__\u001b[0;34m(self, entities)\u001b[0m\n\u001b[1;32m    335\u001b[0m         \u001b[0;32mif\u001b[0m \u001b[0misinstance\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mentities\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mstring_types\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    336\u001b[0m             \u001b[0;31m# allow calls like trained_model['office'], as a shorthand for trained_model[['office']]\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 337\u001b[0;31m             \u001b[0;32mreturn\u001b[0m \u001b[0mself\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mget_vector\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mentities\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    338\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    339\u001b[0m         \u001b[0;32mreturn\u001b[0m \u001b[0mvstack\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mget_vector\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mentity\u001b[0m\u001b[0;34m)\u001b[0m \u001b[0;32mfor\u001b[0m \u001b[0mentity\u001b[0m \u001b[0;32min\u001b[0m \u001b[0mentities\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
            "\u001b[0;32m/usr/local/lib/python3.6/dist-packages/gensim/models/keyedvectors.py\u001b[0m in \u001b[0;36mget_vector\u001b[0;34m(self, word)\u001b[0m\n\u001b[1;32m    453\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    454\u001b[0m     \u001b[0;32mdef\u001b[0m \u001b[0mget_vector\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mword\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 455\u001b[0;31m         \u001b[0;32mreturn\u001b[0m \u001b[0mself\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mword_vec\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mword\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    456\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    457\u001b[0m     \u001b[0;32mdef\u001b[0m \u001b[0mwords_closer_than\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mw1\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mw2\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
            "\u001b[0;32m/usr/local/lib/python3.6/dist-packages/gensim/models/keyedvectors.py\u001b[0m in \u001b[0;36mword_vec\u001b[0;34m(self, word, use_norm)\u001b[0m\n\u001b[1;32m    450\u001b[0m             \u001b[0;32mreturn\u001b[0m \u001b[0mresult\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    451\u001b[0m         \u001b[0;32melse\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 452\u001b[0;31m             \u001b[0;32mraise\u001b[0m \u001b[0mKeyError\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m\"word '%s' not in vocabulary\"\u001b[0m \u001b[0;34m%\u001b[0m \u001b[0mword\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    453\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    454\u001b[0m     \u001b[0;32mdef\u001b[0m \u001b[0mget_vector\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mword\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
            "\u001b[0;31mKeyError\u001b[0m: \"word 'cute' not in vocabulary\""
          ]
        }
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "Qgai1il8WaBO",
        "colab_type": "text"
      },
      "source": [
        "# Re-training Model\n",
        "- Make sure to use `update = True` parameter when building the vocab\n",
        "- The training process use the same parameters, except for the `sentences` and you may use different `epochs`"
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "hy3z6m55Kwnj",
        "colab_type": "code",
        "outputId": "733a5b5c-9781-47ba-e006-08a0e68c2b71",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 222
        }
      },
      "source": [
        "model.build_vocab(clean_wiki_text, update = True)"
      ],
      "execution_count": 0,
      "outputs": [
        {
          "output_type": "stream",
          "text": [
            "2020-04-23 14:11:00,298 : INFO : collecting all words and their counts\n",
            "2020-04-23 14:11:00,299 : INFO : PROGRESS: at sentence #0, processed 0 words, keeping 0 word types\n",
            "2020-04-23 14:11:00,317 : INFO : collected 7254 word types from a corpus of 48577 raw words and 12 sentences\n",
            "2020-04-23 14:11:00,318 : INFO : Updating model with new vocabulary\n",
            "2020-04-23 14:11:00,327 : INFO : New added 714 unique words (8% of original 7968) and increased the count of 714 pre-existing words (8% of original 7968)\n",
            "2020-04-23 14:11:00,333 : INFO : deleting the raw counts dictionary of 7254 items\n",
            "2020-04-23 14:11:00,334 : INFO : sample=0.001 downsamples 112 most-common words\n",
            "2020-04-23 14:11:00,335 : INFO : downsampling leaves estimated 43768 word corpus (127.3% of prior 34394)\n",
            "2020-04-23 14:11:00,382 : INFO : estimated required memory for 1428 words and 300 dimensions: 4141200 bytes\n",
            "2020-04-23 14:11:00,383 : INFO : updating layer weights\n"
          ],
          "name": "stderr"
        }
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "9MmKW0W4GJjA",
        "colab_type": "code",
        "outputId": "fbe97ead-5211-4369-9298-e4dcd949fb52",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 35
        }
      },
      "source": [
        "new_vocab = list(model.wv.vocab)\n",
        "print(model) # vocab: 23190 -> 23207"
      ],
      "execution_count": 0,
      "outputs": [
        {
          "output_type": "stream",
          "text": [
            "Word2Vec(vocab=23207, size=300, alpha=0.005)\n"
          ],
          "name": "stdout"
        }
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "xivg5CATYc1d",
        "colab_type": "text"
      },
      "source": [
        "Our vocab gain new 17 words. Here is the list:"
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "hY58w-ePYTg4",
        "colab_type": "code",
        "outputId": "e04095be-a038-448e-ce1c-528bf8e084f8",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 331
        }
      },
      "source": [
        "set(new_vocab) - set(old_vocab)"
      ],
      "execution_count": 0,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "{'brow',\n",
              " 'cocps',\n",
              " 'cute',\n",
              " 'cuteness',\n",
              " 'enovid',\n",
              " 'lolita',\n",
              " 'lolitas',\n",
              " 'mdna',\n",
              " 'mestranol',\n",
              " 'norethisterone',\n",
              " 'noretynodrel',\n",
              " 'pincus',\n",
              " 'progestins',\n",
              " 'searle',\n",
              " 'taimyr',\n",
              " 'ucl',\n",
              " 'ybp'}"
            ]
          },
          "metadata": {
            "tags": []
          },
          "execution_count": 155
        }
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "eVP8BMr_K8C_",
        "colab_type": "code",
        "outputId": "e1114aaa-a31f-48f0-f59e-b20e477fbe23",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 462
        }
      },
      "source": [
        "new_sentence = clean_wiki_text\n",
        "callback = Callback()\n",
        "\n",
        "model.train(new_sentence,\n",
        "            total_examples = model.corpus_count,\n",
        "            epochs = 5,\n",
        "            compute_loss = True,\n",
        "            callbacks = [callback]) "
      ],
      "execution_count": 0,
      "outputs": [
        {
          "output_type": "stream",
          "text": [
            "2020-04-23 14:01:05,849 : WARNING : Effective 'alpha' higher than previous training cycles\n",
            "2020-04-23 14:01:05,851 : INFO : training model with 3 workers on 23207 vocabulary and 300 features, using sg=1 hs=0 sample=0.001 negative=20 window=5\n",
            "2020-04-23 14:01:06,765 : INFO : worker thread finished; awaiting finish of 2 more threads\n",
            "2020-04-23 14:01:06,810 : INFO : worker thread finished; awaiting finish of 1 more threads\n",
            "2020-04-23 14:01:06,973 : INFO : EPOCH 1 - PROGRESS: at 100.00% examples, 30407 words/s, in_qsize 0, out_qsize 1\n",
            "2020-04-23 14:01:06,974 : INFO : worker thread finished; awaiting finish of 0 more threads\n",
            "2020-04-23 14:01:06,976 : INFO : EPOCH - 1 : training on 48577 raw words (33750 effective words) took 1.1s, 30334 effective words/s\n"
          ],
          "name": "stderr"
        },
        {
          "output_type": "stream",
          "text": [
            "Loss after epoch 1: 292107.4375\n"
          ],
          "name": "stdout"
        },
        {
          "output_type": "stream",
          "text": [
            "2020-04-23 14:01:07,797 : INFO : worker thread finished; awaiting finish of 2 more threads\n",
            "2020-04-23 14:01:07,937 : INFO : worker thread finished; awaiting finish of 1 more threads\n",
            "2020-04-23 14:01:08,120 : INFO : EPOCH 2 - PROGRESS: at 100.00% examples, 29762 words/s, in_qsize 0, out_qsize 1\n",
            "2020-04-23 14:01:08,121 : INFO : worker thread finished; awaiting finish of 0 more threads\n",
            "2020-04-23 14:01:08,123 : INFO : EPOCH - 2 : training on 48577 raw words (33852 effective words) took 1.1s, 29676 effective words/s\n"
          ],
          "name": "stderr"
        },
        {
          "output_type": "stream",
          "text": [
            "Loss after epoch 2: 276003.5\n"
          ],
          "name": "stdout"
        },
        {
          "output_type": "stream",
          "text": [
            "2020-04-23 14:01:08,839 : INFO : worker thread finished; awaiting finish of 2 more threads\n",
            "2020-04-23 14:01:09,061 : INFO : worker thread finished; awaiting finish of 1 more threads\n",
            "2020-04-23 14:01:09,261 : INFO : EPOCH 3 - PROGRESS: at 100.00% examples, 29859 words/s, in_qsize 0, out_qsize 1\n",
            "2020-04-23 14:01:09,262 : INFO : worker thread finished; awaiting finish of 0 more threads\n",
            "2020-04-23 14:01:09,262 : INFO : EPOCH - 3 : training on 48577 raw words (33771 effective words) took 1.1s, 29813 effective words/s\n",
            "2020-04-23 14:01:09,263 : INFO : training on a 145731 raw words (101373 effective words) took 3.4s, 29722 effective words/s\n",
            "2020-04-23 14:01:09,264 : WARNING : under 10 jobs per worker: consider setting a smaller `batch_words' for smoother alpha decay\n"
          ],
          "name": "stderr"
        },
        {
          "output_type": "stream",
          "text": [
            "Loss after epoch 3: 266961.6875\n"
          ],
          "name": "stdout"
        },
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "(101373, 145731)"
            ]
          },
          "metadata": {
            "tags": []
          },
          "execution_count": 144
        }
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "wCLNoEmNX0zb",
        "colab_type": "text"
      },
      "source": [
        "Check if the word \"cute\" already exist in our vocabulary."
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "dhbHBZNIX30E",
        "colab_type": "code",
        "outputId": "a5a3a4bf-1e69-4203-8b5b-ca2319e88be5",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 1000
        }
      },
      "source": [
        "model.wv[\"cute\"]"
      ],
      "execution_count": 0,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "array([ 7.4883504e-04, -2.6113447e-04,  2.3760644e-04,  9.3860098e-04,\n",
              "       -1.4237677e-04,  1.2774217e-03, -3.3907688e-04,  4.6382050e-04,\n",
              "        6.8105041e-04,  5.3802185e-04, -1.6347267e-03,  3.8733837e-04,\n",
              "       -7.1973127e-04,  1.1154407e-03,  1.5528917e-03, -1.3417512e-03,\n",
              "        9.2187803e-04,  5.1689404e-04, -8.2061382e-04, -5.0489570e-04,\n",
              "       -9.9954013e-05,  6.3780806e-04, -2.4767834e-04,  1.0134879e-03,\n",
              "        1.5266651e-03,  5.8589334e-04,  1.0786245e-03,  5.5645261e-04,\n",
              "        1.5204248e-03,  9.8791206e-04, -6.3747400e-04, -9.5522183e-04,\n",
              "        1.2925118e-03, -1.5111063e-03, -1.3946460e-03, -1.0777240e-03,\n",
              "        3.8983164e-04,  1.0519883e-03, -1.2968043e-03,  8.2754489e-04,\n",
              "        1.6474381e-05, -6.5679575e-04, -1.5853419e-03, -1.1392898e-03,\n",
              "       -1.3087797e-03,  3.2610740e-04,  4.7327609e-05,  8.8706170e-04,\n",
              "       -2.8948160e-04,  8.5462432e-04, -1.0303415e-03, -5.9961405e-04,\n",
              "       -1.6496980e-03,  1.2708758e-03,  4.7012491e-04, -2.5329166e-04,\n",
              "        1.2176577e-03, -1.6595341e-03, -4.1973291e-04,  5.0693448e-04,\n",
              "        9.3428959e-04, -9.8644407e-04, -1.4263190e-03,  1.6336609e-04,\n",
              "        5.9814204e-04, -1.9233936e-04,  1.5526236e-03, -5.5584847e-04,\n",
              "       -7.6062651e-04,  5.7692872e-04,  9.5020648e-04, -1.1185592e-03,\n",
              "       -3.1289147e-04,  1.0563846e-03,  4.9994269e-04,  1.2452847e-03,\n",
              "       -3.0367277e-04, -1.5951513e-03, -1.6139341e-03,  7.8893779e-04,\n",
              "       -1.3024600e-04,  1.6521387e-03, -3.0026978e-04, -8.5305923e-04,\n",
              "        1.6476865e-03, -7.0718292e-04,  1.2560762e-04, -1.0437989e-03,\n",
              "        1.1030969e-03,  6.0379645e-04, -8.4459467e-04,  5.6901138e-04,\n",
              "       -1.4216183e-03,  1.2042505e-03, -5.1169301e-04, -1.2862633e-03,\n",
              "       -3.4777371e-05, -1.3016780e-03, -1.0908614e-04, -1.3588875e-03,\n",
              "        6.7578752e-05, -8.9703751e-04,  8.8873703e-04, -9.2919834e-04,\n",
              "        1.3138264e-03, -1.4225042e-03, -1.0501024e-03, -6.3598674e-04,\n",
              "       -1.1548579e-03,  1.5799807e-03, -1.5343602e-04, -7.5295387e-04,\n",
              "       -1.0046985e-03, -1.2332464e-03,  1.2758555e-03,  3.2923659e-04,\n",
              "       -1.0083598e-03, -3.4418947e-04, -1.1685734e-03,  1.4183555e-03,\n",
              "       -1.3136325e-03, -2.3528785e-04, -4.0699958e-04,  1.4186652e-03,\n",
              "       -3.8461934e-04,  6.7357562e-04, -8.0985751e-04, -8.6964814e-05,\n",
              "        9.0202369e-04, -1.3038797e-03,  1.0406113e-03,  1.5148447e-03,\n",
              "       -2.1085031e-04, -5.1161164e-04,  5.4683147e-05, -1.1658026e-04,\n",
              "       -2.2382695e-04,  8.5872045e-04,  1.1912488e-03, -1.3557569e-05,\n",
              "       -4.8516511e-05,  1.3209672e-03, -5.8120006e-04, -1.5409685e-03,\n",
              "       -1.3291337e-04, -1.3625389e-03,  2.8048255e-04,  3.6102321e-04,\n",
              "        8.3877123e-04,  1.4790186e-03, -2.7179084e-04, -6.8081735e-04,\n",
              "        1.1838765e-04,  9.3516003e-04, -6.7258900e-04, -5.2164243e-05,\n",
              "        2.8098334e-04, -8.9579279e-04,  9.4925653e-04, -9.1365562e-04,\n",
              "        8.6318911e-04, -7.9018071e-05, -7.6899618e-05,  1.2507066e-03,\n",
              "        8.7382435e-04,  7.5660227e-04,  6.4914522e-04,  9.2044758e-04,\n",
              "       -1.0871284e-03, -1.4320161e-03,  4.6234473e-04, -1.4752843e-03,\n",
              "        8.3324913e-04, -7.1035256e-04,  9.3753112e-04, -1.2432344e-03,\n",
              "        1.5758887e-03, -5.1841696e-05,  1.4842734e-03,  3.0430555e-04,\n",
              "        1.4256764e-03, -7.8924430e-05,  7.1845762e-04,  4.4605200e-04,\n",
              "        2.7739900e-04, -3.2863102e-04,  1.6091774e-03, -1.3193176e-03,\n",
              "       -6.0073193e-04, -9.3958725e-04,  1.4683981e-03, -2.0735280e-05,\n",
              "        7.8822376e-04, -1.2905075e-03, -6.6572439e-04,  2.4456621e-04,\n",
              "       -1.2180839e-04,  1.4288598e-03, -9.8939973e-04, -1.3482579e-03,\n",
              "        1.6100397e-03, -1.5491251e-03,  5.5271789e-04, -5.5004447e-04,\n",
              "       -1.0231313e-03, -1.1523572e-03, -1.1480823e-03, -6.0254365e-04,\n",
              "       -3.6215832e-04, -1.4089751e-03, -6.9358671e-04,  1.0500770e-03,\n",
              "        1.2490305e-03, -1.1885834e-03, -1.4689759e-03,  4.4794806e-04,\n",
              "       -1.0649763e-03, -1.6246267e-03, -1.1572922e-03,  7.3808513e-04,\n",
              "        2.1806400e-04, -4.4630471e-04, -1.2663065e-03,  8.6710847e-04,\n",
              "        1.4985899e-03,  1.2308470e-03,  8.9746882e-04, -5.6308106e-04,\n",
              "        1.5503252e-03, -3.0926376e-04, -7.1660988e-04, -1.0865767e-03,\n",
              "        1.4244418e-03, -1.2207943e-05,  3.5962195e-04,  2.1064059e-04,\n",
              "       -2.7279122e-04,  1.6674728e-04, -1.3889422e-03, -7.6503056e-04,\n",
              "       -7.8787323e-04,  1.0026072e-03, -4.1243718e-05, -4.6308115e-04,\n",
              "       -9.1717159e-04,  5.9787498e-04, -5.4821110e-04, -4.3549613e-04,\n",
              "       -7.7192148e-04, -1.0223976e-04,  1.3389330e-03,  5.5925437e-04,\n",
              "       -5.8714161e-04,  1.2936928e-04, -7.8465737e-04, -1.2253015e-03,\n",
              "       -1.5893221e-03,  1.5095899e-04, -1.0491702e-03,  1.0790059e-03,\n",
              "        2.2890281e-04,  5.6701351e-04,  2.4793853e-04,  6.2795816e-04,\n",
              "        7.9140649e-04,  1.2000160e-03, -1.8231585e-04,  2.8717110e-05,\n",
              "       -9.0003264e-04, -8.5369695e-04,  4.1884978e-04, -1.3768534e-03,\n",
              "       -1.6645781e-03,  9.6732221e-04,  7.7749474e-04, -1.6214193e-03,\n",
              "        3.8784259e-04,  1.4309674e-03,  1.4299111e-03,  1.0085524e-03,\n",
              "        1.5820303e-03,  4.4600433e-04, -4.2309301e-04,  7.2818139e-04,\n",
              "        9.7440777e-04,  1.1717950e-03, -1.1001730e-04, -9.8769472e-04,\n",
              "        4.2541178e-05,  1.6089394e-03, -1.5671834e-03,  1.2305503e-03,\n",
              "        1.2624614e-03, -4.6494810e-04, -1.2349279e-03, -1.1330221e-03,\n",
              "        3.3908547e-04, -7.4679719e-04, -1.4300540e-03,  2.2811105e-04],\n",
              "      dtype=float32)"
            ]
          },
          "metadata": {
            "tags": []
          },
          "execution_count": 153
        }
      ]
    }
  ]
}