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 EMPIRICISM, FALSIFICATION, PROOF, REPLICATION, VALIDATION, VALIDITY) (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 PROFIT MOTIVE, STAKEHOLDERS.
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 AGENT ORANGE, CONSCIENTIOUS OBJECTOR, 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 consciousness. Investigation is required of factors perpetuating violent media, such as the psychological reasons behind consumer demand for such media, or the mutualistic relationships between News or Hollywood and the Military. Media makers are admired by consumers and critics when they promote human values and produce positive, balanced news and entertainment. (See DESENSITIZATION, TELEVISION, VIDEO GAME VIOLENCE) (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 CYBERSEX, DESENSITIZATION, VIRTUAL WARFARE) (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) without placing a pilot at risk. Predator is a robotic US military spy-plane with missile attack capabilities, used for example in the skies above Afghanistan and Iraq. Other types of remotely piloted vehicle (RPV) may include bomb removal robots, expendable minesweepers, unmanned ground vehicles, patrol boats, mini-helicopters, perimeter sentries, aquabots, microscopic mote sensors with swarm intelligence, and in the future perhaps nanobots. Frighteningly, robotic or virtual warfare can be used in battlefield environments which are too dangerous, or in the case of weapons of mass destruction, too toxic for human soldiers. This also raises the ethical issue of adequate controls on the proliferation of sophisticated military cyber-technologies suitable for deployment of chemical and biological weapons. (See AUTONOMOUS WEAPONS, BIOLOGICAL WARFARE, CYBERWARFARE, INSTITUTION OF WAR, MOTES, NANOBOT, NON-LETHAL WEAPONRY, ROBOT, SPACE WARFARE, VIRTUAL REALITY) (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 BACTERIA, COMPUTER VIRUS, LIFE, VIROID) (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 BATES, SENSES) (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 ENVIRONMENTAL CODE OF CONDUCT, STEWARDSHIP, SUSTAINABLE CORPORATION). (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 MINERAL AND VITAMIN DEFICIENCY, MINERALS, NIACIN, NUTRITION, VITAMIN A, VITAMIN B, VITAMIN B COMPLEX, VITAMIN C, VITAMIN D, VITAMIN E, VITAMIN K). (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 -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 MINERAL AND VITAMIN DEFICIENCY, MINERALS, NIACIN, NUTRITION, VITAMIN, VITAMIN B, VITAMIN B COMPLEX, VITAMIN C, VITAMIN D, VITAMIN E, VITAMIN K). (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 in many other metabolic reactions. It"s, thus, necessary for the healthy functioning of the cardiovascular and nervous 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 germ, unpolished rice, peas, soybeans but most plants contain trace amounts. Organ meats, pork and egg yolk are also rich sources of thiamine. Beriberi is a severe thiamine 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 B6 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 MINERAL AND VITAMIN DEFICIENCY, MINERALS, NIACIN, NUTRITION, VITAMIN, VITAMIN A, VITAMIN B COMPLEX, VITAMIN C, VITAMIN D, VITAMIN E, VITAMIN K). (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 VITAMIN B, FOLIC ACID). (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 nutrients such as iron, B vitamins, vitamins A & E, calcium and certain amino acids. By promoting the formation of strong connective tissue it helps to heal wounds and burns, and by enhancing the function of the immune system it helps to resist and combat disease. Physical stressors such as illness, fever, continuous medication (oral contraceptive use), cigarette smoking and 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 vitamin C deficiency disease. Ascorbic acid is water soluble, sensitive to oxygen, heat, light, alkalis and copperware. Plentiful in rose hips, tomatoes, parsley, winter cress, green pepper, broccoli, citrus fruit and in moderate amounts in all fresh vegetables and fruit. (See MINERAL AND VITAMIN DEFICIENCY, MINERALS, NIACIN, NUTRITION, VITAMIN, VITAMIN A, VITAMIN B, VITAMIN B COMPLEX, VITAMIN D, VITAMIN E, VITAMIN K). (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 MINERAL AND VITAMIN DEFICIENCY, MINERALS, NIACIN, NUTRITION, VITAMIN, VITAMIN A, VITAMIN B, VITAMIN B COMPLEX, VITAMIN C, VITAMIN E, VITAMIN K). (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 MINERAL AND VITAMIN DEFICIENCY, MINERALS, NIACIN, NUTRITION, VITAMIN, VITAMIN A, VITAMIN B, VITAMIN B COMPLEX, VITAMIN C, VITAMIN D, VITAMIN K). (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 MINERAL AND VITAMIN DEFICIENCY, MINERALS, NIACIN, NUTRITION, VITAMIN, VITAMIN A, VITAMIN B, VITAMIN B COMPLEX, VITAMIN C, VITAMIN D, VITAMIN E). (IP)
VNTR (Variable Number of Tandem Repeats): Short repeated sequence of 11-16bp: GGAGGTGGGCAGGA[A/G]G. The presence of core sequences favors the high unequal recombination rate (10 fold, compared to other genome regions). In consequence, the number of such repeats shows a high degree of divergence between individuals, accounting therefore for its high polymorphism and usefulness in linkage or forensic analyses. (GK)