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  • hypernephroma (pathology)

    Renal carcinoma, malignant tumour affecting the epithelial (covering and lining) cells of the kidney. Most renal carcinomas appear in persons past 40 years of age, with peak incidence around the sixth or seventh decade. They tend to arise in persons with vascular disorders of the kidneys; because

  • Hyperoliidae (amphibian family)

    Anura: Annotated classification: Family Hyperoliidae No fossil record; 8 presacral vertebrae; vertebral column procoelous with Presacral VIII usually biconcave; intercalary cartilages present; 3 or 4 tarsals; aquatic larvae; 19 genera, 226 species; adult size 1.5–8.7 cm (0.5–3 inches); 4 subfamilies: Hyperoliinae (Africa and Madagascar), Kassininae (Africa), Leptopelinae (Africa), and…

  • Hyperoliinae (amphibian subfamily)

    Anura: Annotated classification: 5–3 inches); 4 subfamilies: Hyperoliinae (Africa and Madagascar), Kassininae (Africa), Leptopelinae (Africa), and Tachycneminae (Seychelles). Family Mantellidae No fossil record; 8 presacral vertebrae; vertebral column procoelous; intercalary cartilages present; 3 tarsals; aquatic larvae; 3 genera, 61 species;

  • Hyperolius (amphibian)

    frog: Sedge frogs (Hyperolius), for example, are climbing African frogs with adhesive toe disks. The flying frogs (Rhacophorus) are tree-dwelling, Old World rhacophorids; they can glide 12 to 15 metres (40 to 50 feet) by means of expanded webbing between the fingers and toes (see tree…

  • hyperon (subatomic particle)

    Hyperon, quasi-stable member of a class of subatomic particles known as baryons that are composed of three quarks. More massive than their more-familiar baryon cousins, the nucleons (protons and neutrons), hyperons are distinct from them in that they contain one or more strange quarks. Hyperons, in

  • Hyperoodon (mammal genus)

    beaked whale: Paleontology and classification: Genus Hyperoodon (bottlenose whales) 2 species, 1 primarily of the North Atlantic and the other of far southern seas and around Antarctica. Genus Indopacetus (Longman’s beaked whale) 1 Indo-Pacific species identified only from skeletons in 1926 and 1955.

  • Hyperoodon ampullatus (species of mammal)

    cetacean: Breathing and diving: …a harpooned bottlenose whale (Hyperoodon ampullatus) that dived for two hours, surfaced, and then dived again. Patterns of locomotion and breathing are very important to whale watchers identifying whales at a distance, as different species show different blow heights and shapes. Right whales, for instance, have an unequal inclination…

  • Hyperoodon planifrons (mammal)

    bottlenose whale: The maxillary crests of the southern bottlenose whale (H. planifrons) are more modestly developed.

  • Hyperoodontidae (mammal)

    Beaked whale, (family Ziphiidae), any of 23 species of medium-sized toothed whales that have an extended snout, including the bottlenose whales. Little is known about this family of cetaceans; one species was first described in 1995, two others are known only from skeletal remains, and the bodies

  • hyperopia (visual disorder)

    Hyperopia, refractive error or abnormality in which the cornea and lens of the eye focus the image of the visual field at an imaginary point behind the retina (the light-sensitive layer of tissue lining the back and sides of the eye). The retina thus receives an unfocused image of near objects,

  • hyperparasitism (zoology)

    hymenopteran: General features: Hyperparasitism—the parasitic habit of one species upon another parasitic species—has also attracted attention. Polyembryony, the development of many individuals (as many as 1,000) from a single egg, is an unusual phenomenon occurring in some members of the families Chalcididae and Proctotrupidae. Parthenogenesis (production of young…

  • hyperparathyroidism (pathology)

    Hyperparathyroidism, abnormal increase in the secretion of parathormone by one or more parathyroid glands. Hyperparathyroidism may be primary or secondary. In primary hyperparathyroidism, one or more parathyroid glands produces excessive amounts of parathormone. This causes an increase in serum

  • hyperphagia (biology)

    motivation: Hunger: …produces a condition known as hyperphagia, in which animals overeat and gain enormous amounts of weight. Damage to a different area known as the lateral hypothalamus (located on the sides of the hypothalamus) produces a total lack of eating known as aphagia, as well as a lack of drinking, or…

  • hyperphenylalaninemia (medical disorder)

    phenylketonuria: …to a general disorder called hyperphenylalaninemia, characterized by abnormally high levels of phenylalanine in the blood and urine. The symptoms of hyperphenylalaninemia include impaired cognitive function, seizures, and behavioral and developmental abnormalities that may become apparent within months of birth.

  • hyperpipiecolic acidemia (pathology)

    metabolic disease: Peroxisomal disorders: (cerebrohepatorenal) syndrome, neonatal adrenoleukodystrophy, hyperpipecolic acidemia, and infantile Refsum disease. Patients may have severely decreased muscle tone (hypotonia), cerebral malformations, seizures, and an enlarged liver in infancy. Many develop eye abnormalities, in particular a defect in retinal pigment. Patients with Zellweger syndrome also may have small kidney cysts and…

  • hyperplasia (pathology)

    tumour: …commonly in other conditions; (2) hyperplasia, or an increase in the number of cells within a given zone; in some instances it may constitute the only criterion of tumour formation; (3) anaplasia, or a regression of the physical characteristics of a cell toward a more primitive or undifferentiated type; this…

  • hyperplastic symptom (plant pathology)

    plant disease: Symptoms: necrotic, hypoplastic, and hyperplastic or hypertrophic. These categories reflect abnormal effects on host cells, tissues, and organs that can be seen without a hand lens or microscope.

  • hyperpolarization (biology)

    nervous system: The neuronal membrane: …even more negative is called hyperpolarization, while any change tending to make it less negative is called depolarization.

  • hypersensitivity

    Allergy, hypersensitivity reaction by the body to foreign substances (antigens) that in similar amounts and circumstances are harmless within the bodies of other people. Antigens that provoke an allergic reaction are called allergens. Typical allergens include pollens, drugs, lints, bacteria,

  • hypersensitivity angiitis (pathology)

    connective tissue disease: Necrotizing vasculitides: Hypersensitivity angiitis tends to involve smaller blood vessels than those affected in polyarteritis nodosa. Frequently, the affected person seems to have experienced hypersensitivity to various medications, particularly penicillin, sulfonamides, and iodides.

  • hypersensitivity pneumonia (pathology)

    pneumonia: Hypersensitivity pneumonia: Hypersensitivity pneumonias are a spectrum of disorders that arise from an allergic response to the inhalation of a variety of organic dusts. These pneumonias may occur following exposure to moldy hay or sugarcane, room humidifiers, and air-conditioning ducts, all of which contain the…

  • hypersensitivity pneumonitis (pathology)

    farmer's lung: …diseases that are categorized as hypersensitivity pneumonitis; these include pigeon breeder’s lung (also called bird fancier’s, or bird breeder’s, lung), mushroom worker’s lung, cheesewasher’s lung, and coffee worker’s lung.

  • hypersomnia (pathology)

    sleep: Hypersomnia of central origin: Idiopathic hypersomnia (excessive sleeping without a known cause) may involve either excessive daytime sleepiness and drowsiness or a nocturnal sleep period of greater than normal duration, but it does not include sleep-onset REM periods, as seen in narcolepsy. One reported concomitant of hypersomnia, the failure…

  • hypersonic flight

    supersonic flight: …sound (Mach 5), the term hypersonic flight is employed. An object traveling through Earth’s atmosphere at supersonic speed generates a sonic boom—i.e., a shock wave heard on the ground as a sound like a loud explosion.

  • hypersound (physics)

    ultrasonics: Hypersound, sometimes called praetersound or microsound, is sound waves of frequencies greater than 1013 hertz. At such high frequencies it is very difficult for a sound wave to propagate efficiently; indeed, above a frequency of about 1.25 × 1013 hertz it is impossible for longitudinal…

  • hypersthene chondrite (meteorite)

    chondrite: These are carbonaceous chondrites, ordinary chondrites, and enstatite chondrites.

  • hypersusceptibility (pathology)

    poison: Allergies: …caused by the terms hypersensitivity, hypersusceptibility, and idiosyncrasy. Hypersensitivity is a reaction to a chemical or substance in certain individuals and has a basis in the immune system. Hypersusceptibility is an increased predisposition of certain individuals to react to a chemical. Because of biological variability among humans, some individuals respond…

  • Hypertalk (computer language)

    Hypertalk, a computer programming language designed in 1985 as “programming for the rest of us” by American computer scientist Bill Atkinson for Apple’s Macintosh. Using a simple English-like syntax, Hypertalk enabled anyone to combine text, graphics, and audio quickly into “linked stacks” that

  • hypertensin (peptide)

    pharmaceutical industry: Contribution of scientific knowledge to drug discovery: …inactive angiotensin I to active angiotensin II by angiotensin-converting enzyme (ACE) and the interaction of angiotensin II with its physiologic receptors, including AT1 receptors. Angiotensin II interacts with AT1 receptors to raise blood pressure. Knowledge of the biochemistry and physiology of this system suggested to scientists that new drugs could…

  • hypertension (pathology)

    Hypertension, condition that arises when the blood pressure is abnormally high. Hypertension occurs when the body’s smaller blood vessels (the arterioles) narrow, causing the blood to exert excessive pressure against the vessel walls and forcing the heart to work harder to maintain the pressure.

  • hypertext (computer science)

    Hypertext, the linking of related pieces of information by electronic connections in order to allow a user easy access between them. Hypertext is a feature of some computer programs that allow the user of electronic media to select a word from text and receive additional information pertaining to t

  • hypertext markup language (computer science)

    HTML, a formatting system for displaying text, graphics, and audio retrieved over the Internet on a computer monitor. Each retrieval unit is known as a Web page (from World Wide Web), and such pages frequently contain hypertext links that allow related pages to be retrieved. HTML is the markup

  • HyperText Transfer Protocol (computer science)

    HTTP, standard application-level protocol used for exchanging files on the World Wide Web. HTTP runs on top of the TCP/IP protocol. Web browsers are HTTP clients that send file requests to Web servers, which in turn handle the requests via an HTTP service. HTTP was originally proposed in 1989 by

  • hyperthelia

    Hyperthelia, abnormal presence of accessory nipples, a condition of relatively frequent occurrence (1 percent of male and female human population). The nipples usually occur along the primitive milk line, between the armpit and groin, corresponding to the distribution in lower animals. Usually

  • hyperthermia (therapy)

    therapeutics: Hyperthermia: Some tumours are more sensitive than the surrounding healthy tissue to temperatures around 43 °C (109.4 °F). Sensitivity to heat is increased in the centre of tumours, where the blood supply is poor and radiation is less effective. A tumour may be heated using…

  • hyperthermophile (biology)

    extremophile: …°C [140 and 176 °F]); hyperthermophilic (optimal growth above 80 °C [176 °F]); psychrophilic (optimal growth at 15 °C [60 °F] or lower, with a maximum tolerant temperature of 20 °C [68 °F] and minimal growth at or below 0 °C [32 °F]); piezophilic, or barophilic (optimal growth at high…

  • hyperthermophilic organism (biology)

    extremophile: …°C [140 and 176 °F]); hyperthermophilic (optimal growth above 80 °C [176 °F]); psychrophilic (optimal growth at 15 °C [60 °F] or lower, with a maximum tolerant temperature of 20 °C [68 °F] and minimal growth at or below 0 °C [32 °F]); piezophilic, or barophilic (optimal growth at high…

  • hyperthyroidism (pathology)

    Hyperthyroidism, excess production of thyroid hormone by the thyroid gland. Most patients with hyperthyroidism have an enlarged thyroid gland (goitre), but the characteristics of the enlargement vary. Examples of thyroid disorders that give rise to hyperthyroidism include diffuse goitre (Graves

  • hypertime (physics)

    time: Time in the special theory of relativity: …advance with respect to a hypertime, perhaps a new time direction orthogonal to the old one. Perhaps it could be a fifth dimension, as has been used in describing the de Sitter universe as a four-dimensional hypersurface in a five-dimensional space. The question may be asked, however, what advantage such…

  • hypertragulid (fossil mammal family)

    artiodactyl: Evolution and paleontology: The hypertragulids were a mainly Oligocene group of chevrotain-like forms related to the Protoceratidae. The latter had horns above their noses, a position unique among artiodactyls, as well as in the usual position. The North American Miocene (23 million to 5.3 million years ago) produced some…

  • Hypertragulidae (fossil mammal family)

    artiodactyl: Evolution and paleontology: The hypertragulids were a mainly Oligocene group of chevrotain-like forms related to the Protoceratidae. The latter had horns above their noses, a position unique among artiodactyls, as well as in the usual position. The North American Miocene (23 million to 5.3 million years ago) produced some…

  • hypertrichosis (congenital disorder)

    Hypertrichosis, excessive, abnormal hairiness that may be localized or cover the entire body. Hypertrichosis is associated with disorders such as anorexia, repeated skin trauma, systemic illness, metabolic disorders, and exposure to certain drugs and chemicals. In very rare instances the disorder

  • hypertrophic cardiomyopathy (disease)

    cardiomyopathy: In hypertrophic cardiomyopathy, the ventricles are quite small owing to abnormal growth and arrangement of the cardiac muscle fibres. This form of the disease is often hereditary and has been associated with mutations in several different genes, each of which encodes a protein necessary for the…

  • hypertrophic osteoarthropathy (pathology)

    joint disease: Hypertrophic osteoarthropathy: In approximately 5 to 10 percent of persons who have primary tumours within the chest, the ends of the bones near the joints become enlarged and painful. New bone is formed in the periosteum, and only occasionally do abnormalities develop within the joints…

  • hypertrophic scar (biology)

    scar: …of overscarring is that of hypertrophic scars, in which the scar grows overly thick but remains confined within the limits of the wound. Keloids and hypertrophic scars are most troublesome when they result from serious burns and cover large areas of the skin; these may inhibit a person’s movement, especially…

  • hypertrophic spondylitis (pathology)

    spondylitis: Hypertrophic spondylitis, also known as osteoarthritis of the spine, is a degenerative disease seen mostly in individuals over the age of 50. It is characterized by the destruction of intervertebral disks and the growth of spurs on the vertebrae themselves. Treatment includes rest, the application…

  • hypertrophy (biology)

    human disease: Health versus disease: …(the process is known as hypertrophy). This occurs in certain forms of heart disease, especially in those involving long-standing high blood pressure or structural defects of the heart valves. A large heart, therefore, may be a sign of disease. On the other hand, it is not uncommon for athletes to…

  • hyperuricemia (pathology)

    arthritis: Crystalloid arthritis: …uric acid excretion, leading to hyperuricemia. Although acute gouty attacks are self-limited when hyperuricemia is left untreated for years, such attacks can recur intermittently, involving multiple joints. Chronic tophaceous gout occurs when, after about 10 years, chalky, pasty deposits of monosodium urate crystals begin to accumulate in the soft tissue,…

  • hypervalence

    chemical bonding: Hypervalence: Lewis structures and the octet rule jointly offer a succinct indication of the type of bonding that occurs in molecules and show the pattern of single and multiple bonds between the atoms. There are many compounds, however, that do not conform to the octet…

  • hypervalent compound

    chemical bonding: Hypervalence: Lewis structures and the octet rule jointly offer a succinct indication of the type of bonding that occurs in molecules and show the pattern of single and multiple bonds between the atoms. There are many compounds, however, that do not conform to the octet…

  • hypervalinemia (pathology)

    maple syrup urine disease: …acids are isovaleric acidemia and hypervalinemia. In the former, the metabolism of leucine alone is blocked at one specific step by a defect in an enzyme called isovaleryl coenzyme A dehydrogenase. As a result, the level of isovaleric acid rises markedly in body fluids, and the affected individual suffers from…

  • hypervelocity impact (physics)

    meteorite crater: The impact-cratering process: …extreme speeds is called a hypervelocity impact. Although the resulting depression may bear some resemblance to the hole that results from throwing a pebble into a sandbox, the physical process that occurs is actually much closer to that of an atomic bomb explosion. A large meteorite impact releases an enormous…

  • hyperventilation (pathology)

    Hyperventilation, sustained abnormal increase in breathing. During hyperventilation the rate of removal of carbon dioxide from the blood is increased. As the partial pressure of carbon dioxide in the blood decreases, respiratory alkalosis, characterized by decreased acidity or increased alkalinity

  • hypervitaminosis A (pathology)

    nutritional disease: Vitamins: Chronic hypervitaminosis A, usually resulting from a sustained daily intake of 30,000 μg (100,000 IU) for months or years, may result in wide-ranging effects, including loss of bone density and liver damage. Vitamin A toxicity in young infants may be seen in a swelling of the…

  • hypervitaminosis D (pathology)

    vitamin D: …toxic levels, a condition called hypervitaminosis D. An individual experiencing vitamin D poisoning may complain of weakness, fatigue, loss of appetite, nausea, and vomiting. In infants and children there may be growth failure. Because vitamin D is involved in the intestinal absorption and mobilization of calcium, this mineral may reach…

  • hypha (biology)

    fungus: Basic morphology: The filaments, called hyphae (singular hypha), branch repeatedly into a complicated, radially expanding network called the mycelium, which makes up the thallus, or undifferentiated body, of the typical fungus. The mycelium grows by utilizing nutrients from the environment and, upon reaching a certain stage of maturity, forms—either directly…

  • hyphae (biology)

    fungus: Basic morphology: The filaments, called hyphae (singular hypha), branch repeatedly into a complicated, radially expanding network called the mycelium, which makes up the thallus, or undifferentiated body, of the typical fungus. The mycelium grows by utilizing nutrients from the environment and, upon reaching a certain stage of maturity, forms—either directly…

  • Hyphaene (plant genus)

    palm: Distribution: (palmyra palm), Calamus (rattan palm), Hyphaene (doum palm), and Phoenix (date palm) in Africa and Asia. Numbers of individuals of a species may be few or many.

  • Hyphaene compressa (plant)

    palm: Distribution: …and coastal plains of Africa, Hyphaene compressa and Borassus aethiopum occur, often in great abundance. Freshwater swamplands in parts of New Guinea are dominated by Metroxylon sagu. Both the doum palm and the sago palm (Metroxylon) are useful, and their distribution may be due in part to human activities. Eugeissona…

  • hyphal loop (predation)

    fungus: Predation: Other fungi produce hyphal loops that ensnare small animals, thereby allowing the fungus to use its haustoria to penetrate and kill a trapped animal. Perhaps the most amazing of these fungal traps are the so-called constricting rings of some species of Arthrobotrys, Dactylella, and Dactylaria—soil-inhabiting fungi easily grown…

  • Hyphasis River (river, India)

    Beas River, river in Himachal Pradesh and Punjab states, northwestern India. It is one of the five rivers that give the Punjab (“Five Rivers”) its name. The Beas rises at an elevation of 14,308 feet (4,361 metres) at Rohtang Pass in the western (Punjab) Himalayas (a section of the vast Himalayas

  • hyphen

    punctuation: Punctuation in Greek and Latin to 1600: The hyphen, to mark words divided at the ends of lines, appeared late in the 10th century; single at first, it was often doubled in the period between the 14th and 18th centuries.

  • Hyphessobrycon innesi (fish)

    tetra: The neon tetra (Paracheirodon, or Hyphessobrycon, innesi) is a slender fish that is very popular with aquarium owners. It grows to a length of 4 cm, its hind parts are coloured a gleaming red, and its sides have a neonlike blue-green stripe. The cardinal tetra (Cheirodon…

  • hypho-borane (chemical compound)

    borane: Structure and bonding of boranes: …with two missing vertices; (4) hypho- (Greek, meaning “to weave” or “a net”), the most open clusters, with boron atoms occupying n corners of an (n + 3)-cornered closo-polyhedron; and (5) klado- (Greek, meaning “branch”), n vertices of an n + 4-vertex closo-polyhedron occupied by n boron atoms. Members of…

  • hypho-carborane (chemical compound)

    carborane: Reactions and synthesis of carboranes: The first hypho-carborane, C3B4H12, was reported in 1993 by Robert Greatrex, Norman N. Greenwood, and their colleagues.

  • Hyphochytriales (chromist order)

    fungus: Annotated classification: Order Hyphochytriales Mostly marine; motile cells bear a single tinsel flagellum (a flagellum with short side branches along the central axis, comblike); example genera include Hyphochytrium and Rhizidiomyces. Phylum Labyrinthulomycota Found in both salt water and fresh water in association with algae and other chromists; feeding…

  • Hyphochytriomycota (chromist phylum)

    Hyphochytriomycota, phylum of mostly aquatic funguslike organisms in the kingdom Chromista. The taxonomy of the group is contentious but is generally thought to contain about 20 species. The phylum is distinguished by the asexual production of motile cells (zoospores) with a single, anterior,

  • Hyphomicrobium (bacterium genus)

    bacteria: Budding: In Hyphomicrobium a hyphal filament (prostheca) grows out of one end of the cell, and the bud grows out of the tip of the prostheca, separated by a relatively long distance from the mother cell.

  • hypnagogic state (state of consciousness)

    dream: Dreamlike activities: …as he awakens, respectively called hypnagogic and hypnopompic reveries. During sleep itself there are nightmares, observable signs of sexual activity, and sleepwalking. Even people who ostensibly are awake may show evidence of such related phenomena as hallucinating, trance behaviour, and reactions to drugs.

  • Hypnerotomachia Poliphili (work printed by Manutius)

    graphic design: Renaissance book design: …was the Aldine Press’s 1499 Hypnerotomachia Poliphili, believed to be written by Francesco Colonna. The design of the work achieves an understated simplicity and tonal harmony, and its elegant synthesis of type and image has seldom been equaled. The layout combined exquisitely light woodcuts by an anonymous illustrator with roman…

  • hypnopompic state (state of consciousness)

    dream: Dreamlike activities: respectively called hypnagogic and hypnopompic reveries. During sleep itself there are nightmares, observable signs of sexual activity, and sleepwalking. Even people who ostensibly are awake may show evidence of such related phenomena as hallucinating, trance behaviour, and reactions to drugs.

  • Hypnos (Greco-Roman god)

    Hypnos, Greco-Roman god of sleep. Hypnos was the son of Nyx (Night) and the twin brother of Thanatos (Death). In Greek myth he is variously described as living in the underworld or on the island of Lemnos ( according to Homer) or (according to Book XI of Ovid’s Metamorphoses) in a dark, musty cave

  • hypnosis (psychology)

    Hypnosis, special psychological state with certain physiological attributes, resembling sleep only superficially and marked by a functioning of the individual at a level of awareness other than the ordinary conscious state. This state is characterized by a degree of increased receptiveness and

  • Hypnosis and Suggestibility (work by Hull)

    Clark L. Hull: …studies formed the basis of Hypnosis and Suggestibility (1933).

  • hypnotic

    Sedative-hypnotic drug, chemical substance used to reduce tension and anxiety and induce calm (sedative effect) or to induce sleep (hypnotic effect). Most such drugs exert a quieting or calming effect at low doses and a sleep-inducing effect in larger doses. Sedative-hypnotic drugs tend to depress

  • Hypnotic Eye (album by Tom Petty and the Heartbreakers)

    Tom Petty: Hypnotic Eye, another Heartbreakers’ effort, topped the Billboard album chart in 2014.

  • hypnozoite (biology)

    malaria: The course of the disease: …the liver in a “hypnozoite” stage for months or even years before emerging to attack red blood cells and cause a relapse of the disease.

  • hypnozygote (biology)

    Gymnodinium: Sexual reproduction often results in hypnozygotes (thick-walled resting cysts) that can remain dormant in mud and other sediments until conditions are favourable for growth. Asexual reproduction is primarily through binary fission.

  • Hypnum (plant)

    Carpet moss, (genus Hypnum), genus of about 80 species of mosses (family Hypnaceae) that form dense green mats in many habitats throughout the world, especially on decaying wood in moist areas. A few species are aquatic. About 20 species occur in North America, though the taxonomy of the group is

  • Hypnum crista-castrensis (plant species)

    Feather moss, (Ptilium, formerly Hypnum, crista-castrensis), the only species of the genus Ptilium, it is a widely distributed plant of the subclass Bryidae that forms dense light green mats on rocks, rotten wood, or peaty soil, especially in mountain forests of the Northern Hemisphere. The erect

  • Hypnum curvifolium (plant)

    Sheet moss, (Hypnum curvifolium), a species of carpet moss (family Hypnaceae). The names sheet moss and carpet moss refer to the growth pattern of the plants, which often form large carpetlike mats on rocks or soil. This species is sometimes used by florists in constructing flower

  • hypo (chemical compound)

    sodium: Principal compounds: Sodium thiosulfate (sodium hyposulfite), Na2S2O3, is used by photographers to fix developed negatives and prints; it acts by dissolving the part of the silver salts coated onto film which remain unchanged by exposure to light.

  • Hypoaeolian mode (music)

    Aeolian mode: …its plagal (lower-range) form, the Hypoaeolian mode, had A as their finalis (the tone on which a piece in a given mode ends). The Ionian mode and its plagal counterpart, the Hypoionian, had their finalis on C. The pitch series of the Ionian mode matches that of the major scale.

  • hypoaldosteronism (medical disorder)

    Hypoaldosteronism, abnormally low serum levels of aldosterone, a steroid hormone secreted by the adrenal gland. Hypoaldosteronism nearly always arises as a result of disorders in which the adrenal glands are destroyed. However, there does exist a disease in which defective aldosterone synthesis and

  • hypobaric storage (food processing)

    fruit processing: Storage: Hypobaric storage involves the cold storage of fruit under partial vacuum. Typical conditions include pressures as low as 80 and 40 millimetres of mercury and temperatures of 5° C (40° F). Hypobaric conditions reduce ethylene production and respiration rates; the result is an extraordinarily high-quality…

  • hypoblast (cell layer)

    blastocyst: …layer of cells, called the hypoblast, between the inner cell mass and the cavity. These cells contribute to the formation of the embryonic endoderm, from which derive the respiratory and digestive tracts.

  • hypobranchial gland (anatomy)

    mollusk: External features: …epithelium called mucus tracts or hypobranchial glands, and the outlets for the digestive, excretory, and reproductive systems. A loss of the ctenidia (along with the mucus tracts) is seen in scaphopods, advanced gastropods, septibranch bivalves, and solenogasters.

  • hypobranchial muscle (anatomy)

    muscle: Jawed fishes: The hypobranchial muscles of jawed fishes are straplike muscles running from the pectoral girdle to the structures of the visceral skeleton, the jaws, and the gill bars. Some muscles, such as the coracomandibularis, are specialized as jaw openers, although most of the work of jaw opening…

  • hypocalcemia (pathology)

    calcium deficiency: Severe calcium deficiency, or hypocalcemia, which is defined as a reduction of calcium levels in the bloodstream below a certain normal range, has its own clinical manifestations. The main syndrome is tetany, which involves sensations of numbness and tingling around the mouth and fingertips and painful aches and spasms…

  • hypocalcemic action (physiology)

    hormone: Ultimobranchial tissue and calcitonin: …calcium in the blood (hypocalcemic action) when it rises above the normal level. Its secretion probably is regulated by a negative feedback relationship between the gland and the blood plasma. The hormone affects bone, which is an active tissue. It undergoes not only growth but also remodeling as it…

  • hypocalcification (anatomy)

    enamel: …instances, from genetic anomaly; (2) hypocalcification, in which there is insufficient calcium and a soft enamel is produced; this may result, for example, from excess fluorine in the diet. See also cementum; dentine.

  • hypocarp (plant)

    cashew: …swollen stem (hypocarp), called the cashew apple. The cashew apple, which is an accessory fruit (e.g., not a true fruit), is about three times as large as the true fruit and is reddish or yellow. The true fruit has two walls, or shells. The outer shell is smooth, thin, and…

  • hypocaust (architecture)

    Hypocaust, in building construction, open space below a floor that is heated by gases from a fire or furnace below and that allows the passage of hot air to heat the room above. This type of heating was developed by the Romans, who used it not only in the warm and hot rooms of the baths but also

  • hypocentre (seismology)

    earthquake: Principal types of seismic waves: …the Earth, is called the focus, or hypocentre. The point at the surface immediately above the focus is known as the epicentre.

  • hypochile (plant anatomy)

    orchid: Natural history: …or hood-shaped portion called the hypochile above; an elongate, sometimes fluted part, the mesochile; and a bucket-shaped epichile. The epichile is partially filled with water during the last few hours before the flower opens and for a short time afterward by two faucetlike organs located at the base of the…

  • hypochlorite (chemical compound)

    poison: Inorganic compounds: Hypochlorites are often used as bleaching agents. In low concentrations, as in household bleaches, hypochlorites have little toxicity but may be irritating to tissues; they can, however, be corrosive at high concentrations. Cyanide ions poison the oxidative metabolic machinery of cells so that insufficient energy…

  • hypochondria (psychology)

    Illness anxiety disorder, mental disorder characterized by an excessive preoccupation with illness and a tendency to fear or believe that one has a serious disease on the basis of the presence of insignificant physical signs or symptoms. Illness anxiety disorder is thought to be derived from the

  • Hypochondriac, The (play by Molière)

    The Imaginary Invalid, comedy in three acts by Molière, produced in 1673 and published in 1674 as Le Malade imaginaire. It was also translated as The Hypochondriac. Molière wrote the play while ill, and he collapsed during his own performance of the title role, that of Argan, a hypochondriac who

  • hypochondriasis (psychology)

    Illness anxiety disorder, mental disorder characterized by an excessive preoccupation with illness and a tendency to fear or believe that one has a serious disease on the basis of the presence of insignificant physical signs or symptoms. Illness anxiety disorder is thought to be derived from the

  • hypochondroplasia (medical disorder)

    dwarfism: Hypochondroplasia resembles achondroplasia except that the head is of normal size. Diastrophic dwarfism is characterized by progressive, crippling skeletal deformities. There is a high risk of death from respiratory failure during early infancy; thereafter the prospect of a normal life span is good. Intelligence is…

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