UNESCO/IUBS/EUBIOS BIOETHICS DICTIONARY - "V"s

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

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VACCINATION: (Latin vacca 'cow'). Any inoculation of killed or attenuated disease-bearing microorganisms given to induce immunity to or reduce the adverse effects associated with that particular disease. Vaccination can be administered by injection (intramuscularly, subcutaneously or intradermally) or by oral dosing. Vaccinating children against such diseases as measles, whooping cough, diphtheria and polio has been made compulsory in a number of countries. However, some oppose compulsory vaccination programs because, like any inoculation, it may infrequently cause infection and even more infrequently induce severe allergic reactions. (See VACCINE, IMMUNITY, IMMUNE SYSTEM, JENNER, EDWARD) (IP)

VACCINE: (Latin vaccinus 'relating to the cow'). A preparation containing killed or attenuated disease-bearing microorganisms used to induce immunity to that particular disease. Vaccines may be used as single or combination preparations. (See VACCINATION, IMMUNITY, IMMUNE SYSTEM, JENNER, EDWARD) (IP)

VALIDATION: The process of assessing the validity of a theory, argument or statistical result. This usually involves an independent check of the reported results, preferably including investigation of the same topic from a different angle. (See VALIDITY, KNOWLEDGE VALIDATION, SENSITIVITY ANALYSIS) (MP)

VALIDITY: Validity is a property of reasoning, arguments or logical inferences. Valid reasoning has coherence and agreement of its premises, which together logically imply the conclusion (whether or not any of these are actually true). In non-philosophical parlance, a valid argument must in addition not be a weak argument or include false statements. Validity can also be property of measurement and modeling, for example content, construct and criterion validity. (See COHERENCE, VALIDATION, VERIFICATION, VERACITY, PROOF) (MP)

VALIUM: See DIAZEPAM.

VALUE: 1. The worth of something/someone, can be monetary worth, aesthetic worth, ethical worth or worthy as a means in itself. 2. of a thing as measured by the amount of other things for which it can be exchanged, or estimated in terms of a medium of exchange (from Old French valeir meaning worth). (IP) 3. In general it means the importance or worth, price put by humans on a species / natural resources / concept. Measured in terms of utility for humans, e.g. time spent on an item. Intrinsic value is the concept of independent existence, having a predetermined purpose of a species/organ, places an objective value on individual animal, species, ecosystem, biosphere. See the concept developed by Holmes Rolston III, for example. A hierarchy of values is giving different values in the order of importance of organisms/ecosystem. (JA)

VARIABLE: 1. Containing variety, fluctuating. 2. In statistics, a measurement or attribute, able to be graphed and analyzed. (See DIVERSITY, DEPENDENT VARIABLE, INDEPENDENT VARIABLE) (MP)

VARIANCE: A measure of dispersion, variance is equal to the standard deviation squared. (See STANDARD DEVIATION, MEASURES OF DISPERSION) (MP)  

VARIETY: refers to a distinct group of plant or animal within the same species that share a number of characteristics which are passed on from one generation to the next and which distinguishes the plant/animal of one variety from those of another. (IP)

VASECTOMY: Sterilization of a man by surgical excision of a part of the vas deferens. (DM)

VDRL TEST: Venereal Disease Research Laboratory Test, a microscopic agglutination screening test for the detection of Waisermann antibodies in the serum of syphilitic patients. (JA)

VECTOR: DNA molecule originating from a virus, a bacterium, or the cell of a higher organism used to carry additional DNA base pairs; vectors introduce foreign DNA into host cells, where it can be reproduced in large quantities. Examples are plasmics, cosmids and yeast artificial chromosomes. (DM)

VEDAS: (Sanskrit: "knowledge") Sacred literature of Hinduism, composed from around 1500 BCE and comprising the four Vedas: the ‘Rig Veda’ containing hymns of praise, the "Suma Veda" with sacrificial chants, the "Yajur Veda" with sacrificial formulae, and the "Atharva Veda" comprised of spells and legends. The Vedas were appended with the "Brahmanas", "Aranyakas" and "Upanishads", which were more philosophically inclined and highlighted non-sacrificial means to salvation. (See UPANISHADS) (IP & MP)

VEDIC: A period in Indian/Asian cuLture, dating back 3,500 BC to 800 BC. Features include personification of nature, ascribed divinity to natural resouces like rivers, mountains, water, air, fire, land. (JA)

VEGETARIANISM: The custom of eating only vegetable products and no meat. Vast numbers of vegetarians, especially in India, also eat milk and milk products. In some parts of the world, notably Bengal, fish is accepted as part of a vegetarian diet. It can be debated whether eggs are acceptable. Reasons for vegetarianism may be (1) respect for the rights of animals, (2) health, (3) spirituality. The Brahmin caste in India is traditionally vegetarian. They are also known for a high standard of health.

Many people believe that eating meat is necessary for their health, while others successfully live long, healthy vegetarian lives. There might be a "gene for vegetarianism" in the sense that certain people, perhaps including the Brahmins, might have genetic sequences, which produce enzymes, or other substances, which allow them to get optimal nutrition from non-meat sources. But this hypothesis has not yet been adequately researched. Another hypothesis, which has not yet been adequately researched, proposes that younger, growing people need meat, while older people can do well on a vegetarian diet. (FL)

VEGETATIVE PROPAGATION: Includes to cut bits of mature plants that are grown to produce genetically identical plants, analogous to animal cloning. (JA)

VEGETATIVE STATE: A state in which a patient (usually through brain damage) is not brain dead, shows EEG activity, goes through periods of sleep and wakefulness, but cannot communicate with others and shows no evidence of consciousness. The "permanent vegetative state" must be distinguished from the "persistent vegetative state". Dr Keith Andrews of London has succeeded in returning patients to various levels of consciousness after four or more years in the persistent vegetative state. The Israeli hospital, Beit Levenstein, has had similar success with accident and terror victims. Raanan Gillon once argued in the British Medical Journal that in spite of Dr Andrews' success, the investment is not justified within a National Health Service whose resources are limited. But one may question what right we have to judge the meaning of people's lives, even if their level of consciousness and function seem to be low. The term, "vegetative" is unfortunate and insulting to patients, families and caregivers. Perhaps "persistent coma" would be a more successful term. (FL)

VENTILATORS : Mechanical devices used to produce or assist pulmonary ventilation. Also called respirators. (DM)

VENUS: 1. in Roman mythology the Goddess of sexual love and desire with her kingdom consisting of those with strong passions who were embroiled in a multitude of love affairs and sometimes in a confused welter of problems (see Aphrodite) 2. The oldest known human statuettes are the fertility figurines or Venuses of the Paleolithic Age crafted around and before 22,000 BC 3. The planet orbiting next to earth nearer to the sun who is known as the brilliant Morning or Evening "Star"; her phases, discovered by Galileo and accessible to the simplest astronomical telescope, are spectacular so the planet has dazzled humankind since antiquity. The NASA Magellan probe, between 1990 and 1992, monitored two complete rotations of the planet and established an entire map with unequaled resolution. (IP)

VENUS'S-FLYTRAP: genus Dionaea are carnivorous, heterotrophic plants which augment their nitrogen and phosphorus supply by capturing and digesting flies and other insects. None of the carnivorous plants must feed on insects as they grow adequately without them, but in nature they grow faster and are a darker green when insects are available to them because the extra supply of nitrogen is used to make more proteins and chlorophyll, as well as other nitrogen-containing compounds. (IP)

VERIFICATION: 1. Management: Checking that the data being used are the same as those in the original source; a systematic search for errors. 2. Philosophy: The sometimes difficult process of showing a statement to be conclusively true. The ‘Verification Principle’ of Logical Positivism was the belief that meaningful propositions must be empirical and verifiable. (See REPLICATION, VALIDITY, VALIDATION, PROOF, FALSIFICATION, EMPIRICISM) (MP)

VERTEBRATE: The group or individual animals of the phylum Chordata, subphylum vertebrata. Vertebrates are characterized by the presence of a spine. (RW)

VESTED INTERESTS: See STAKEHOLDERS, PROFIT MOTIVE.

VIABILITY: The potential of the fetus to survive outside the uterus. (DM)

VIABLE: Alive - capable of replication like a cell or DNA in a cell. (JA)

VIAGRA: Trademark name for sildenafil citrate, an oral therapy for erectile dysfunction. Unlike previously approved treatments for impotency, Viagra does not directly cause penile erections; instead it affects the male's response to sexual simulation. The drug acts by enhancing the smooth-muscle relaxant effects of nitric oxide; a chemical normally released in response to sexual stimulation. This smooth-muscle relaxation allows increased blood flow into certain areas of the penis, leading to an erection. It is important to note, however, that impotency is often associated with other underlying disorders such as hypertension, diabetes, coronary artery disease and severe anxiety states. Therefore, Viagra cannot be seen as a panacea and is contraindicated in patients with known organic disorders, especially if undergoing other drug therapies. Viagra has not been studied in combination with other treatment regimes. (IP)

VIROID: One of the simplest examples of life or proto-life, a viroid is a short circle or coil of unprotected RNA. (See VIRUS) (MP)

VIDEO CONFERENCING: The gathering of executives or experts in an interactive audiovisual software environment on the internet. Desktop webcams deliver images of participants who can meet face-to-face in cyberspace without the inconvenience and expense of travel. Virtual reality technologies have the potential to revolutionize online education and acquaintance. (See CYBERSPACE, VIRTUAL REALITY) (MP)

VIDEO GAME VIOLENCE: The computer or video game is a traditionally violent medium, often training young users in hand-eye coordination tasks such as shooting, combat skills and other competitive activities. The "first-person shooter" action genre in particular (pioneered by Doom and Quake ) has taken violence to a new level. "Game over" is often heralded by the death of the protagonist, for example in the popular Tomb Raider, the gamer is in effect watching a girl undergoing a continuous series of different gory deaths. Such games may have a desensitizing effect on the often immaturely developed psyche of young gamers. This will be of greater concern in the era of virtual reality, where the distinctions between virtuality and reality will become increasingly indistinguishable. (See DESENSITIZATION, VIOLENT MEDIA, VIRTUAL REALITY) (MP)

VIENNA, CIRCLE: A group of philosophers who flourished in Vienna during the 1920's and l930's, until they had to flee Nazism. They attempted to rid scientific, as well as ordinary language from metaphysics, which they described as nonsense. Their famous principle said that a sentence is meaningful if, and only if, it is either analytic or empirically verifiable. By analytic is meant a sentence, which can be proved by the methods of logic or mathematics. Sentences, which do not meet this criterion, are considered to be nonsense. The movement may have been a reaction against much of the ideological verbiage in European nationalism, Fascism, and Nazism. But they may have reacted too extremely in that they also rejected all religious and ethical language. Statements of ethics were considered nonsensical in that they failed to describe any facts in the world, for after all good and bad do not describe empirically observable qualities like colours and sounds. But although statements of ethics have no scientific meaning, they may have an emotive meaning in that they serve to express feelings. (FL)

VIETNAM WAR: Beginning in 1959-1960 and lasting till 1975. It was a war between the northern (mostly communist government of Ho Chi Minh in Hanoi) and southern (anti-communist government of Ngo Dinh Diem in Saigon) zones of Vietnam as they emerged from the Geneva Agreement of 1954. The conflict was also a 'cold war' struggle between the United States and the Soviet Union. At the height of the war (1967-1968) there were 500,000 American troops in Vietnam. American air attacks on the north began in 1965 when they also began to send combat troops. American forces were withdrawn in 1973 and in 1975 South Vietnam fell under communist forces and Saigon was re-named Ho Chi Minh City. (See CONSCIENTIOUS OBJECTOR, AGENT ORANGE, INSTITUTION OF WAR) (IP)

VIOLENT MEDIA: The debate has been long-lived as to the effects of violent movies, television and video games on society and individuals. Conflict has been considered essential to successful drama, and violence is common currency in the media of many countries. Violence may be central to comedy as well as drama, as the typical misfortunes of someone in a slapstick or cartoon fantasy would testify. Context, tone and intent of a work make the difference between a war movie and an anti-war movie. A violent movie can still promote an ethical value system, illustrate significant issues, or even act as a relatively safe outlet for aggressive tension. However, gratuitous violence or vengeance without proper illustration of negative consequences may glorify non-ethical social values and standards, and may lead to desensitization or even imitation in some unstable or immature personalities. In such individuals fight moves and other aggressive acts may be added to the repertoire – an extreme example perhaps being the extraordinary plot leading to September 11, 2001. Media has a large role in injecting ideas into the infosphere and shaping public c required of factors perpetuating violent media, such as the psychological reasons behind consumer demand for such media, or the mutualistic relationships between News oredia makers are admired by consumers and critics when they promote human values and produce positive, balanced news and entertainment. (See VIDEO GAME VIOLENCE, TELEVISION, DESENSITIZATION) (MP)

VIRTUAL REALITY: (Virtual "essence or appearance of" + Reality "existing environment") A computer generated environment, simulating and resembling actual reality or constructing an imaginary artificial world. The virtual reality environment is interactive with the virtual traveller through equipment such as electronic gloves to monitor hand movements and a helmet with TV displays to each eye. This results in the illusion of entering and interacting within a constructed or simulated reality. An interesting example would be to enter the visual field of a robot and watch yourself. The technology has many applications including remote surgery, space/deep sea exploration, unmanned military units, skills training, cyberspace conferencing and other tasks involving interaction in three-dimensions with computer technology. Not least among these applications is the entertainment industry, where potential ripples to the psychosocial fabric include tactile simulated sex at a distance (teledildonics), highly addictive psychedelic playgrounds, and desensitization to reality from the regular exposures of military trainees and young virtual reality gamers. (See VIRTUAL WARFARE, CYBERSEX, DESENSITIZATION) (MP)

VIRTUAL WARFARE: Armed conflict linked with electronic and computer technologies - virtual warfare is actual warfare, but waged at a distance with virtual reality, for example tele-operated gun vehicles. Cyber-warfare involves different types of activities, and autonomous weapons differ in their independent ability to locate and direct themselves unaided. In casualty-averse modern warfare the unmanned aerial vehicle (UAV) is becoming increasingly standard, able to perform live reconnaissance (e.g. ‘Global Hawk’ surveillance aircraft) and offensive missions (e.g. ‘Predator’ drone) pilotedwarm intruction, biological weapons. (See VIRTUAL REALITY, CYBERWARFARE, AUTONOMOUS WEAPONS, SPACE WARFARE, ROBOT, MOTE, NANOBOT, BIOLOGICAL WARFARE, INSTITUTION OF WAR, NON-LETHAL WEAPONS) (MP & IP)

VIRTUES: Character traits which are considered to be morally praiseworthy, such as compassion, honesty, integrity, and trustworthiness. (DM)

VIRULENCE: The degree of pathogenicity exhibited by a strain of microorganism. (JA)

VIRUS: (Latin: 'slime' or 'poison') Any of a large group of sub-microscopic organisms comprised of a protein coat with genetic material in the form of a nucleic acid molecule (DNA or RNA, double or single strand, linear or circular). A virus is however unable to reproduce outside the host cell of another plant or animal, and for this reason is often not included within the definition of life. Viruses nevertheless live at the borderlines, providing insight into the nature and processes of life and evolution. Some viruses are pathogenic to plants and animals, for example causing human diseases including the common cold, herpes, measles, smallpox and HIV/AIDS. (See VIROID, BACTERIA, LIFE, COMPUTER VIRUS) (MP)

VISION: (Latin visus 'vision') 1. Exceptional strategic perception and foresight, a characteristic of effective leadership. The visionary leader's concepts may appear idealistic or unrealistic, but vision is based on a higher order of perception concerned with fundamental insights, the big picture, and projection of current concerns into the future. (See FORESIGHT, VISIONARY COMPANY) (MP) 2. The sense of sight. The eye is the organ that provides vision, situated in the orbital cavity and supplied by the optic nerve or second cranial nerve. Structurally the two eyes are separate but, unlike the ear, some of their activities are coordinated so that they function as a pair; for example, it is possible to see with one eye but three-dimensional vision is impaired when only one eye is used. Light waves, which travel at a speed of 300,000 km per second, are reflected into the eyes by objects within the field of vision. Light is a combination of all colors of the visual (rainbow) spectrum; that is, red, yellow, green, blue, indigo and violet. The spectrum of light is broad but only a small part is visible to the human eye. Beyond the long end there are infrared (heat), radar and radio waves; beyond the short end are ultraviolet (uv), x-ray and cosmic waves. Other animals can see differing spectra; for example the honeybee can see uv light - an evolutionary adaptation to its way of life. A specific color is perceived when one wavelength is reflected by an object and all others are absorbed; for example, an object appears red when only red wavelength is reflected, white when all wavelengths are reflected and black when they are all absorbed. The light reflected from objects within the visual field is focused on the retinas of both eyes. Before reaching the retina light rays pass successively through the conjunctiva, cornea, aqueous fluid, lens and vitreous body - all are denser than air and with the exception of the lens they have a constant refractive power close to that of water. It is the elastic structure of the lens which changes the refraction, bending all the light rays in order to focus them onto the retina (light from distant objects needs least refraction and as an object comes closer the amount required increases). Looking at near objects tires the eyes more quickly due to the continuous use of the ciliary muscle suspending the lens - adding credit to precautionary advice about close work, especially at computer terminals. The retina is the photosensitive part of the eye, with the light-sensitive cells called the rods and cones. Light rays cause chemical changes in photosensitive pigments in these cells, which emit nerve impulses that pass to the visual lobes of the cerebrum via the optic nerves. It is in the brain where perception of different colors takes place. The eye is a delicate organ which is protected by several structures such as eyebrows, eyelids, eyelashes and lacrimal (tear) glands. (See SENSES, BATES WILLIAM) (IP)

VISIONARY COMPANY: Corporations or organizations which are the premier institutions of their industries, have long-term success and make a significant impact on the world. The distinguishing feature of visionary companies is that they are driven not by profits but by vision - they have clear core values and meaningful objectives which manage to inspire staff, stakeholders and society. (See SUSTAINABLE CORPORATION, ENVIRONMENTAL CODE OF CONDUCT, STEWARDSHIP) (MP)

VITALISM: the view that a patient’s life is self-determining, therefore, it is a doctor’s duty to sustain life even if it were decided that the patient were better off dead.

VITAMIN: (Latin vita "life"). Any one of several unrelated organic compounds that an organism cannot synthesize itself so they must be obtained from the diet, or from dietary supplements. They are essential, in small quantity, for normal growth and metabolism and when deficient produce specific-deficiency illnesses. Vitamin loss occurs as a result of handling and preparation of fresh foods during harvesting, heating, pickling, salting, drying, milling, canning and other food-processing methods. Vitamin loss can also be associated with digestive disorders that prevent nutrient absorption and with the use of certain drugs. (See NUTRITION, VITAMIN A, VITAMIN B complex, VITAMIN B, VITAMIN C, VITAMIN D, VITAMIN E, VITAMIN K, NIACIN, MINERALS, MINERAL AND VITAMIN DEFICIENCY) (IP)

VITAMIN A: This vitamin is not found in plants but is synthesized by the animal body from various pigment substances or carotenoids that are common in plants; for example, carrots and apricots advertise their beta -carotene content by their yellow/orange color or tomatoes and red peppers by their lycopene which makes for a deeper orange/red color; but green leafy vegetables such as parsley and spinach are also a rich source of these vital pigments. Animal products such as fish liver oils, liver, milk, cheese, butter and egg yolk are a rich source of vitamin A. Vitamin A is essential for night vision, promotes healthy skin and mucous membranes and is important for skeletal growth and good teeth, for effective digestion, for production of red and white blood corpuscles in the blood, and for lactation (breast feeding). Vitamin A is fat-soluble and is sensitive to oxygen especially if combined with heat. (See NUTRITION, VITAMIN, VITAMIN B complex, VITAMIN B, VITAMIN C, VITAMIN D, VITAMIN E, VITAMIN K, NIACIN, MINERALS, MINERAL AND VITAMIN DEFICIENCY) (IP)

VITAMIN B: 1. Vitamin B₁ or thiamine (Greek theion "containing sulfur" + amine "ammonia") occurs in both plant and animal tissue and plays a key role in the body’s production of energy through the breakdown of carbohydrates and also takes part i systems. Since the vitamin is not stored in the body it must be supplied daily. Vitamin B₁ is found in good quantity in brewer’s yeast, sunflower seeds, wheat germine deficiency disease. 2. Vitamin B₂ or riboflavin (Latin ribose "a 5-carbon sugar" + flavus "yellow") occurs generally in the same foods as vitamin B₁ . Riboflavin is essential for cell growth and for enzymic reactions by which the body oxidizes proteins, fats and carbohydrates. Vitamin B₂ plays an important part in preventing visual disorders especially cataracts. Most plants contain traces of vitamin B₂ but in good quantity can be found in brewer’s yeast, dried almonds, wheat germ, unpolished rice, barley, sweet potatoes. Animal sources are organ meats, milk, cheese and eggs. 3. Vitamin B₆ or pyridoxine occurs in small quantities in most plant and animal tissue but rich sources are meat especially organ meats, yeast, blackstap molasses, wheat bran and wheat germ, soybeans, barley, rice, peanuts, cabbage, potatoes and carrots. Vitamin B ₆ takes part in many enzyme reactions and is particularly important for construction of hormones important in brain function, the production of antibodies, the maintenance of the body’s fluid balance and the effective absorption of vitamin B₁₂. There is an increased need for pyridoxine during pregnancy, breast-feeding and use of oral contraceptives. 4. Vitamin B₁₂ or cyanocobalamin (Greek kyanos "blue" + German kobald "mine goblin"). There is little or no vitamin B₁₂ in plants which is why a strictly vegetarian diet sometimes causes pernicious anemia and risk brain damage. Rich dietary sources are liver, kidney, meats, fish and dairy products. Vitamin B₁₂ is essential for the proper functioning of body cells particularly in the nervous system, bone marrow and the gastrointestinal tract. The vitamin is also involved in the metabolism of fats, proteins and carbohydrates. (See NUTRITION, VITAMIN, VITAMIN B complex, VITAMIN A, VITAMIN C, VITAMIN D, VITAMIN E, VITAMIN K, NIACIN, MINERALS, MINERAL AND VITAMIN DEFICIENCY) (IP)

VITAMIN B COMPLEX : A group of water-soluble vitamins possessing individual structures and biological effects that is defined separately under vitamin B (B₁ through to B₁₂ ). They are present separately or in combination in many foods - especially liver and yeast - and are heat sensitive risking destruction by prolonged cooking. (See FOLIC ACID, VITAMIN B) (IP)

VITAMIN B₉ : See FOLIC ACID.

VITAMIN C: Also called ascorbic acid. (Greek a "not" + scurf "scurvy"). This vitamin is a plant vitamin and occurs to some degree in almost all plants. The human body neither makes or stores vitamin C, thus a continuous supply must be provided in the food. Normal body cell function requires ascorbic acid, as does the formation of intercellular matrices, healthy collagen (the basic protein of connective tissue), bones, teeth, cartilage, skin and capillary walls. Vitamin C promotes the body’s effective use of other nutrientand by enhancing the function of nd other forms of drug abuse all increase the body’s need for vitamin C, as does distress such as chronic anxiety and depression. The body’s need for vitamin C is also elevated during pregnancy and lactation. Scurvy is a vitam. Plentiful in rose hips, tomatoes, parsley, winter cress, green pepper, broccoli, citrITAMIN A, VITAMIN B, VITAMIN D, VITAMIN E, VITAMIN K, NIACIN, MINERALS, MINERAL AND VITAMIN DEFICIENCY) (IP)

VITAMIN D: This vitamin, chemically related to steroids, does not occur in plants but some plants contain compounds called sterols (a form of cholesterol) which can be irradiated with ultraviolet light to make Vitamin D. Yeast and fungi, for example, are rich sources of ergosterol that can be irradiated to make commercial vitamin D. The human skin contains another sterol, which is converted to vitamin D by the ultraviolet part of sunlight that is then absorbed; however, this sterol can be removed by using soap whose alkalinity removes the oil from the skin. Natural sources are fish liver oil, salt-water fish especially sardines and herring, organ meats, milk and egg yolk but requirements can also be met by artificial enrichment of various foods. Vitamin D is essential for healthy bones and teeth, for proper assimilation and body balance of calcium and phosphorus, and for the prevention or rickets. The vitamin is fat-soluble and is not sensitive to heat, light or oxygen. (See NUTRITION, VITAMIN, VITAMIN B complex, VITAMIN A, VITAMIN B, VITAMIN C, VITAMIN E, VITAMIN K, NIACIN, MINERALS, MINERAL AND VITAMIN DEFICIENCY). (IP)

VITAMIN DEFICIENCY: See MINERAL AND VITAMIN DEFICIENCY.

VITAMIN E: Also called tocopherol. This vitamin occurs in both plant and animal tissue. As an intracellular antioxidant it acts in the body to protect polyunsaturated fatty acids and other fatlike substances such as vitamin A and hormones of the pituitary, adrenal and reproductive glands from oxidation damage. The vitamin also maintains healthy membrane tissue, blood cells and is essential for fertility. It is generally found in whole grains and their oils, green leaves and seeds, thus is in abundance in sunflower oil, cotton seed oil, wheat germ oil and wheat germ, peanuts, olive oil, oatmeal and so on. Since the vitamin is stored in the body for a long time it is also found in butter, liver and eggs. Vitamin E is fat-soluble and is sensitive to oxygen, alkalis and ultraviolet light. (See NUTRITION, VITAMIN, VITAMIN B complex, VITAMIN A, VITAMIN B, VITAMIN C, VITAMIN D, VITAMIN K, NIACIN, MINERALS, MINERAL AND VITAMIN DEFICIENCY) (IP)

VITAMIN K: Occurs primarily in plants but is also synthesized by intestinal bacteria in the small intestine. Vitamin K belongs to a group of compounds known as quinones that are essential for the synthesis by the liver of the blood-clotting enzyme prothrombin. The vitamin is fat-soluble and is sensitive to light, oxygen, strong acids and alkalis. It is found in abundance in alfalfa, green leafy vegetable, soybean oil, kelp, fish-liver oils, blackstrap molasses, liver, yogurt and egg yolk. Deficiency, which can be associated with intestinal or liver disease, is characterized by poor blood coagulation and hemorrhage. Sometimes the vitamin is given prophylactically to infants to prevent hemorrhagic disease. (See NUTRITION, VITAMIN, VITAMIN B complex, VITAMIN A, VITAMIN B, VITAMIN C, VITAMIN D, VITAMIN E, NIACIN, MINERALS, MINERAL AND VITAMIN DEFICIENCY). (IP)

VNTR (VARIABLE NUMBER OF TANDEM REPEATS): Short repeated sequence of 11-16bp: GGAGGTGGGCAGGA[A/G]G. The presence of alpha core sequences favors the high unequal recombination rate (10 fold, compare, accounting therefore for its high polymorphism and usefulness in linkage or forensic analyses. (GK)

VOICE RECOGNITION: See SPEECH RECOGNITION.

VOLUNTARY ADMISSION: Entrance into a mental health facility at a person's request or with his or her consent. (DM)

VOLUNTARY EUTHANASIA: The killing of a patient who is suffering or is afflicted with an incurable disease or condition, for reasons of mercy, at that person's request or with his or her consent. (DM)

VOLUNTARY SIMPLICITY: See HIPPIES and SUFFICIENCY.

VOLUNTARY STERILIZATION: Sterilization performed at the request of, or with the informed consent of, the patient. (DM)

VOLUNTARY ADMISSION: Entrance into a mental health facility at a person's request or with his or her consent. (DM)

VOLUNTARY SIMPLICITY: See SUFFICIENCY, HIPPIES.

VULNERABLE SPECIES: A species or other taxon which is at high risk of becoming extinct in the wild in the medium-term future. This may be indicated by any of the following measures: a) a previous or projected population reduction of at least 20% over whichever is longer of a period of 10 years or three generations, b) extent of occurrence less than 20,000 km² or area of occupancy less than 2000 km² , along with population decline, fragmentation or extreme fluctuations, c) population less than 10,000 mature individuals with continuing decline, d) population less than 1000 mature individuals, or e) probability of extinction in the wild at least 10% within 100 years. (See ENDANGERED SPECIES, CRITICALLY ENDANGERED, GHOST SPECIES, EXTINCTION) (MP)

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