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  • hypochromic macrocytic anemia (medical disorder)

    alcoholism: Chronic diseases: …resulting from vitamin C deficiency; hypochromic macrocytic anemia, caused by folate deficiency, vitamin B12 deficiency, or certain chemotherapeutic agents; and pernicious anemia, resulting from vitamin B12 deficiency. Severe open sores on the skin of alcoholic derelicts whose usual drink is the cheapest form of alcohol—low-quality fortified wines—are sometimes miscalled “wine…

  • hypochromic microcytic anemia (pathology)

    blood disease: Anemia: …with hemoglobin; this is called hypochromic microcytic anemia. In still other cases of anemia, there is no significant alteration in the size, shape, or coloration of the red cells, a condition called normocytic anemia.

  • Hypochytriales (protist)

    protozoan: Annotated classification: Hypochytriales Absorptive heterotrophs. Grow as chytridlike unicells; some also grow as hyphae. Typically parasitic or saprobic. Chrysophyceae (golden algae) Most freshwater. Have a unique feeding cup. Mixotrophy common; some taxa are strictly phagotrophic heterotrophs. Algal taxa possess 1 or 2 plastids per cell.

  • Hypocolius ampelinus (bird)

    Hypocoly, (Hypocolius ampelinus), Middle Eastern songbird believed by some authorities to be related to the waxwing (family Bombycillidae) but often separated as the sole member of the family Hypocoliidae (order Passeriformes). The hypocoly is a slim grayish bird, about 18 cm (7 inches) long, with

  • hypocoly (bird)

    Hypocoly, (Hypocolius ampelinus), Middle Eastern songbird believed by some authorities to be related to the waxwing (family Bombycillidae) but often separated as the sole member of the family Hypocoliidae (order Passeriformes). The hypocoly is a slim grayish bird, about 18 cm (7 inches) long, with

  • hypocoristic name (language)

    name: Forms of personal names: Hypocoristic forms of names are those that are used in familiar, friendly, or intimate situations (usually shortened or otherwise modified)—e.g., Tom for Thomas, Jim for James. Some of these forms are also used as given names, particularly in the United States.

  • hypocortisonism (pathology)

    Addison disease, rare disorder defined by destruction of the outer layer of the adrenal glands, the hormone-producing organs located just above the kidneys. Addison disease is rare because it only occurs when at least 90 percent of the adrenal cortex is destroyed. In the mid-19th century when the

  • hypocotyl (plant anatomy)

    angiosperm: Stems: …a transition region called the hypocotyl. In the developing embryo, the hypocotyl is the embryonic axis that bears the seedling leaves (cotyledons).

  • Hypocreales (fungi order)

    fungus: Annotated classification: Order Hypocreales Parasitic or pathogenic on plants, may cause canker formation; when present, perithecia and stromata are brightly coloured, soft, fleshy, or waxy; asci borne in a basal layer among apical paraphyses; included in subclass Hypocreomycetidae; example genera include Hypocrea, Nectria, Cordyceps, Claviceps, and Niesslia. Order…

  • hypocretin (hormone)

    narcolepsy: …of a hormone known as hypocretin (also known as orexin), which promotes wakefulness. The loss of hypocretin may in turn be linked to an underlying autoimmune disorder in which immune cells target the hormone for destruction. In some persons, autoimmunity against hypocretin is suspected to occur as a result of…

  • hypodactyly (pathology)

    malformation: Somatic characters: …as fingers or toes (polydactyly, hypodactyly [ectrodactyly], brachydactyly), is a frequent anomaly in man and other mammals. In many analyzed cases it has been shown to result from the inheritance of an abnormal gene that produces a localized disturbance of a growth process in the embryo. In the rabbit a…

  • Hypoderma bovis (insect)

    warble fly: …bot, flies Hypoderma lineatum and H. bovis are large, heavy, and beelike. The females deposit their eggs on the legs of cattle. The larvae penetrate the skin, migrate through the body for several months, and produce a characteristic lump, or warble, on the animal’s back. The warble contains a hole,…

  • Hypoderma lineatum (insect)

    warble fly: The warble, or bot, flies Hypoderma lineatum and H. bovis are large, heavy, and beelike. The females deposit their eggs on the legs of cattle. The larvae penetrate the skin, migrate through the body for several months, and produce a characteristic lump, or warble, on the animal’s back. The warble…

  • Hypoderma tarandi (insect)

    warble fly: Oedemagena tarandi is another warble fly that causes economic losses of leather, meat, and milk in reindeer herds.

  • hypodermic syringe (medical instrument)

    blood transfusion: Transfusion procedures and blood storage: …vein by means of a hypodermic syringe and is passed through a plastic tube to a collection bag or bottle to which sodium citrate has been added in order to prevent the blood from clotting. In transfusing blood into the recipient, donor blood of the appropriate type is passed by…

  • hypodermis (plant anatomy)

    tree: Adaptations: …more thick-walled layers called the hypodermis beneath it. The sunken stomates are generally located on all surfaces, and the cavity is filled with wax. The vascular tissue is embedded in a layer of spongy cells called the transfusion tissue, which is thought to facilitate water distribution to the mesophyll.

  • hypodipsia (pathology)

    Adipsia, rare disorder characterized by the lack of thirst even in the presence of dehydration. In adipsia the brain’s thirst centre, located in the hypothalamus, is damaged. People with adipsia have little or no sensation of thirst when they become dehydrated. These people must be instructed, even

  • Hypodorian mode (music)

    Hypodorian mode, in music, second of the eight medieval church modes. See church

  • hypofibrinogenemia (pathology)

    blood disease: Afibrinogenemia: Afibrinogenemia, or hypofibrinogenemia, refers to a reduction in the amount of the clotting factor fibrinogen in the blood. This is seen in rare instances as an inherited disorder, but more commonly it is found as part of the syndrome of disseminated intravascular coagulation (see…

  • hypofunction (hormones)

    human endocrine system: Endocrine hypofunction and receptor defects: …in hormone production, known as hypofunction, is required to maintain homeostasis. One example of hypofunction is decreased production of thyroid hormones during starvation and illness. Because the thyroid hormones control energy expenditure, there is survival value in slowing the body’s metabolism when food intake is low. Thus, there is a…

  • hypogammaglobulinemia (pathology)

    gamma globulin: …it—conditions called, respectively, agammaglobulinemia and hypogammaglobulinemia—have frequently recurring infections because of their inability to develop adequate immunity to infectious diseases. See also antibody.

  • hypogeal germination (botany)

    angiosperm: Seedlings: In hypogeous germination, the hypocotyl remains short and the cotyledons do not emerge from the seed but rather force the radicle and epicotyl axis to elongate out of the seed coat. The seed, with the enclosed cotyledons, remains underground, and the epicotyl grows up through the…

  • hypogeous germination (botany)

    angiosperm: Seedlings: In hypogeous germination, the hypocotyl remains short and the cotyledons do not emerge from the seed but rather force the radicle and epicotyl axis to elongate out of the seed coat. The seed, with the enclosed cotyledons, remains underground, and the epicotyl grows up through the…

  • hypoglossal nerve (anatomy)

    human nervous system: Hypoglossal nerve (CN XII or 12): The hypoglossal nerve innervates certain muscles that control movement of the tongue. From the hypoglossal nucleus in the medulla oblongata, general somatic efferent fibres exit the cranial cavity through the hypoglossal canal and enter the neck in close proximity…

  • hypoglycemia (pathology)

    Hypoglycemia, reduction of the concentration of glucose in the blood below normal levels, commonly occurring as a complication of treatment for diabetes mellitus. In healthy individuals an intricate glucoregulatory system acts rapidly to counter hypoglycemia by reducing insulin production (insulin

  • hypoglycemic encephalopathy (pathology)

    lychee: …fruits has been linked to hypoglycemic encephalopathy and death in a number of children in India, Bangladesh, and Vietnam. The fruits and seeds contain the toxins hypoglycin A and methylene cyclopropyl-glycin, which inhibit the synthesis of glucose and can cause acute hypoglycemia. These toxins are more concentrated in unripe fruits,…

  • hypogonadism (pathology)

    Hypogonadism, in men, decreased testicular function that results in testosterone deficiency and infertility. Hypogonadism is caused by hypothalamic, pituitary, and testicular diseases. Hypothalamic and pituitary diseases that may cause decreased testicular function include tumours and cysts of the

  • hypogonadotropic eunuchoidism (pathology)

    reproductive system disease: Delayed puberty: …glands; this condition is called hypogonadotropic eunuchoidism. The term delayed puberty is usually applied to boys who develop more slowly than the average but who still eventually undergo full sexual development. Only in retrospect—i.e., after the affected person reaches the age of 20—can one clearly differentiate these cases from the…

  • hypogyneismus (psychology)

    frigidity: …therapists by the general term hypogyneismus, the inability of a woman to obtain sexual satisfaction under otherwise appropriate circumstances.

  • hypogynous flower (plant anatomy)

    angiosperm: The gynoecium: In hypogynous flowers, the perianth and stamens are attached to the receptacle below the gynoecium; the ovary is superior to these organs, and the remaining floral organs arise from below the point of origin of the carpel. In perigynous flowers, a hypanthium (a floral tube formed…

  • hypoid gear (mechanical part)

    automobile: Axles: The adoption of hypoid or offset spiral bevel gears in the rear axle provided an increase in this clearance by lowering the drive pinion below the centre of the axle shafts.

  • Hypoionian mode (music)

    mode: Gradual emergence of major and minor tonality: The Ionian and Hypoionian modes correspond to the major mode, the Aeolian and Hypoaeolian modes to the “natural” minor mode. The 12 modes of the Dodecachordon comprise authentic and plagal structures with tonal centres on the notes C, D, E, F,…

  • hypokalemia (pathology)

    Potassium deficiency, condition in which potassium is insufficient or is not utilized properly. Potassium is a mineral that forms positive ions (electrically charged particles) in solution and is an essential constituent of cellular fluids. The relationship between potassium and the metabolism of

  • hypokalemic periodic paralysis (pathology)

    muscle disease: The periodic paralyses: In hypokalemic periodic paralysis, the level of potassium in the blood falls during the attack, which also can be precipitated by anything that tends to lower the potassium level. Hyperkalemic periodic paralysis, on the other hand, is associated with an increase in the potassium level. An…

  • hypolimnion (water layer)

    hydrosphere: Lake waters: …the lower water layer (the hypolimnion) of lakes. The starting point is photosynthesis, represented by the following reaction:

  • hypolipidemic drug

    Hypolipidemic drug, any agent the reduces the level of lipids and lipoproteins (lipid-protein complexes) in the blood. Lipoproteins bind cholesterol and can accumulate in blood vessels. High levels of specific lipoproteins, namely, low-density lipoprotein (LDL) and very low-density lipoprotein

  • Hypolocrian mode (music)

    Locrian mode: …its plagal (lower-register) counterpart, the Hypolocrian mode, existed in principal long before they were mentioned by the Swiss humanist Henricus Glareanus in his landmark music treatise Dodecachordon (1547). In that work Glareanus expanded the standing system of church modes to accommodate the increasingly common major and minor modes as well…

  • Hypolydian mode (music)

    Hypolydian mode, in music, sixth of the eight medieval church modes. See church

  • hypomagnesemia (pathology)

    Magnesium deficiency, condition in which magnesium is insufficient or is not utilized properly. Magnesium is a mineral that is essential to a variety of cellular metabolic reactions and sometimes has the ability to replace a portion of body calcium. It is also required for the synthesis of

  • hypomania (mental illness)

    seasonal affective disorder: …experience a condition known as hypomania, in which they have rapid thoughts and speech, have grandiose ideas about themselves, or become short-tempered, irritable, and impulsive. If these symptoms become severe, affected individuals may show bad judgment and behave recklessly—characteristics of a condition described as mania. People with SAD may suffer…

  • Hypomixolydian mode (music)

    Hypomixolydian mode, in music, last of the eight medieval church modes. See church

  • Hypomnematismoi kai semeioseis gnomikai (work by Metochites)

    Theodore Metochites: His best-known work, Hypomnematismoi kai semeioseis gnomikai (“Personal Comments and Annotations”), commonly designated the “Philosophical and Historical Miscellany,” is an encyclopaedic collection of tracts and essays on classical thought, history, and literature, comprising more than 80 Greek authors. Other treatises on physics, astronomy, physiology, and Aristotelian psychology survive…

  • hyponatremia (blood disorder)

    nutritional disease: Sodium: Symptoms of hyponatremia, or low blood sodium, include muscle cramps, nausea, dizziness, weakness, and eventually shock and coma. After prolonged high-intensity exertion in the heat, sodium balance can be restored by drinking beverages containing sodium and glucose (so-called sports drinks) and by eating salted food. Drinking a…

  • Hypopachus cuneus (amphibian)

    narrow-mouthed toad: The Mexican narrow-mouthed toad, or sheep frog (Hypopachus cuneus), is similar but is larger and has a yellow stripe on its back. It hides in burrows, pack rat nests, or, as does the eastern narrow-mouth, under objects lying on the ground.

  • hypoparathyroidism (pathology)

    Hypoparathyroidism, inadequate secretion of parathormone. Hypoparathyroidism can be due to decreased secretion of parathormone or, less often, to decreased action of parathormone (pseudohypoparathyroidism). In either case, hypoparathyroidism results in decreased mobilization of calcium from bone,

  • hypopharynx (anatomy)

    human respiratory system: The pharynx: …the pharynx is called the hypopharynx. Its anterior wall is formed by the posterior part of the tongue. Lying directly above the larynx, it represents the site where the pathways of air and food cross each other: Air from the nasal cavity flows into the larynx, and food from the…

  • hypophosphatasia (pathology)

    Hypophosphatasia, rare hereditary disorder characterized by very low levels of tissue and serum alkaline phosphatase (the enzyme necessary in cell processes such as muscle metabolism and bone formation). The disease is more common in females. Growth of the infant is retarded; permanent stunting

  • hypophosphatemia (pathology)

    Hypophosphatemia, reduction in the concentration of phosphate in the blood serum, thus disrupting the body’s energy metabolism and impairing the delivery of oxygen through the bloodstream to the tissues. Hypophosphatemia usually occurs in conjunction with other metabolic disturbances that affect

  • hypophosphite (chemical compound)

    oxyacid: Hypophosphorous acid and hypophosphite salts: Free hypophosphorous acid, H3PO2, is prepared by acidifying aqueous solutions of hypophosphite ions, H2PO2−. For example, the solution remaining when phosphine is prepared from the reaction of white phosphorus and a base contains the H2PO2− ion. If barium hydroxide (BaOH) is used as…

  • hypophosphorous acid (chemical compound)

    oxyacid: Hypophosphorous acid and hypophosphite salts: Free hypophosphorous acid, H3PO2, is prepared by acidifying aqueous solutions of hypophosphite ions, H2PO2−. For example, the solution remaining when phosphine is prepared from the reaction of white phosphorus and a base contains the H2PO2− ion. If barium hydroxide (BaOH)…

  • Hypophrygian mode (music)

    Hypophrygian mode, in music, fourth of the eight medieval church modes. See church

  • Hypophthalmichthys molitrix (fish)

    Asian carp: black carp (Mylopharyngodon piceus), and silver carp (Hypophthalmichthys molitrix), following their accidental introduction into waterways in the United States, are collectively referred to as Asian carp.

  • Hypophthalmichthys nobilis (fish)

    Asian carp: The grass carp (Ctenopharyngodon idella), bighead carp (Hypophthalmichthys nobilis), black carp (Mylopharyngodon piceus), and silver carp (Hypophthalmichthys molitrix), following their accidental introduction into waterways in the United States, are collectively referred to as Asian carp.

  • hypophysis (anatomy)

    Pituitary gland, ductless gland of the endocrine system that secretes hormones directly into the bloodstream. The term hypophysis (from the Greek for “lying under”)—another name for the pituitary—refers to the gland’s position on the underside of the brain. The pituitary gland is called the “master

  • hypophysis (plant embryo)

    plant development: Origin of the primary organs: The hypophysis will give rise to the radicle and the root cap; the cells of the suspensor will degenerate as the embryo matures.

  • hypophysis cerebri (anatomy)

    Pituitary gland, ductless gland of the endocrine system that secretes hormones directly into the bloodstream. The term hypophysis (from the Greek for “lying under”)—another name for the pituitary—refers to the gland’s position on the underside of the brain. The pituitary gland is called the “master

  • hypopituitarism (pathology)

    Hypopituitarism, deficiency of pituitary hormones caused by damage to the pituitary gland. Patients may have a deficiency of one or all pituitary hormones, including vasopressin (antidiuretic hormone), the hormone of the posterior pituitary gland that controls the excretion of urine. Deficiency of

  • hypoplasia (dentistry)

    enamel: …of enamel may occur: (1) hypoplasia, in which the amount of matrix is insufficient, so that there is a lack of enamel; this may result from infection or malnutrition during development or, in rare instances, from genetic anomaly; (2) hypocalcification, in which there is insufficient calcium and a soft enamel…

  • hypoplastic left heart syndrome (pathology)

    congenital heart disease: One example is hypoplastic left heart syndrome, a very serious condition in which the left ventricle and other structures are underdeveloped, severely compromising blood flow through the body. Fortunately, surgical advances have made it possible to correct many defects, so that some patients who once would have succumbed…

  • hypoplastic symptom (plant pathology)

    plant disease: Symptoms: categories: prenecrotic, 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.

  • hypoprothrombinemia (pathology)

    Hypoprothrombinemia, disease characterized by a deficiency of the blood-clotting substance prothrombin, resulting in a tendency to prolonged bleeding. Hypoprothrombinemia is usually associated with a lack of vitamin K, which is necessary for the synthesis of prothrombin in the liver cells. In

  • hyposensitization (medicine)

    Desensitization, treatment that attempts to eliminate allergic reactions, as of hay fever or bronchial asthma, by a series of injections in graded strengths of the substance to which the person is sensitive (e.g., pollen, house dust). Extracts of the material to be injected are purified and put i

  • hyposexuality (pathology)

    frigidity: …only with great difficulty (hyposexuality); and the inability to achieve orgasm (anorgasmia). Failure of sexual response in females—as in males—may have specific physical sources; such is the case of women who experience vaginal spasms (vaginismus) or pain (dyspareunia) during attempted intercourse. Likewise, female sexual response may be impaired by…

  • Hyposmocoma (insect genus)

    Hyposmocoma, moth genus containing more than 350 described species in the family Cosmopterigidae (order Lepidoptera). The group is endemic to the Hawaiian Islands and contains multiple species noted for their amphibious caterpillar stage, during which they can survive underwater for unlimited

  • Hyposmocoma molluscivora (insect)

    Hyposmocoma: Larvae of the species H. molluscivora are predacious, feeding on terrestrial snails of the genus Tornatellides. H. molluscivora larvae trap their prey by using silk lines to bind the snails to leaves. The larva then enters the shell of the snail and feeds.

  • hyposomnia (sleep disorder)

    Insomnia, the inability to sleep adequately. Causes may include poor sleeping conditions, circulatory or brain disorders, a respiratory disorder known as apnea, stress, or other physical or mental disorders. Insomnia is not harmful if it is only occasional; the body is readily restored by a few

  • hypospadias (pathology)

    urogenital malformation: In hypospadias, often familial, the urethra opens on the underside of the penis. Plastic surgery can repair both anomalies.

  • hypostasis (theology)

    Christianity: Emergence of official doctrine: …ousia (nature or essence) and hypostasis (entity, used as virtually equivalent to prosōpon, person). (In Latin these terms became substantia and persona.) Christ was said to have two natures, one of which was of the same nature (homoousios) as the Father, whereas the other was of the same nature as…

  • hypostatic gene (genetics)

    heredity: Epistatic genes: …gene it subordinates is the hypostatic gene. The gene for albinism (lack of pigment) in humans is an epistatic gene. It is not part of the interacting skin-colour genes described above; rather, its dominant allele is necessary for the development of any skin pigment, and its recessive homozygous state results…

  • hypostatic union (theology)

    Incarnation: …been referred to as the hypostatic union. The union of the two natures has not resulted in their diminution or mixture; rather, the identity of each is believed to have been preserved.

  • hypostyle hall

    Hypostyle hall, in architecture, interior space whose roof rests on pillars or columns. The word means literally “under pillars,” and the design allows for the construction of large spaces—as in temples, palaces, or public buildings—without the need for arches. It was used extensively in ancient

  • hyposulfite of soda (chemical compound)

    Hyposulfite of soda, most important salt of thiosulfuric acid, an unstable compound of sulfur

  • hypotension (pathology)

    Hypotension, condition in which the blood pressure is abnormally low, either because of reduced blood volume or because of increased blood-vessel capacity. Though not in itself an indication of ill health, it often accompanies disease. Extensive bleeding is an obvious cause of reduced blood volume

  • hypotensive drug (pharmacology)

    cardiovascular drug: Drugs affecting the blood vessels: Hypotensive drugs, particularly nitroglycerine tablets and calcium channel blockers, are often used to relieve angina pectoris. Angina often is the result of partial occlusion of the coronary vessels by fatty deposits (atheroma) or blood clots. Hypotensive drugs reduce arterial blood pressure and cardiac output and…

  • hypothalamic amenorrhea (pathology)

    oligomenorrhea: Hypothalamic amenorrhea is a term used to describe the condition of women who have oligomenorrhea or amenorrhea as a result of decreased pulsatile secretion of gonadotropin-releasing hormone (GnRH), which stimulates the synthesis and secretion of the two primary gonadotropins—luteinizing hormone (LH) and follicle-stimulating

  • hypothalamic releasing factor (physiology)

    hormone: Melanocyte-stimulating hormone (intermedin): …neurosecretions from the hypothalamus called hypothalamic releasing factors. Chemical characterization of these factors shows them to be simple polypeptides, in which respect they resemble the hypothalamic polypeptide hormones. This neurosecretory system is best understood in mammals, in which good evidence has been found for the existence of a separate releasing…

  • hypothalamic releasing hormone (physiology)

    hormone: Melanocyte-stimulating hormone (intermedin): …neurosecretions from the hypothalamus called hypothalamic releasing factors. Chemical characterization of these factors shows them to be simple polypeptides, in which respect they resemble the hypothalamic polypeptide hormones. This neurosecretory system is best understood in mammals, in which good evidence has been found for the existence of a separate releasing…

  • hypothalamic-hypophyseal portal circulation (physiology)

    human endocrine system: Modes of hormone transport: One system, the hypothalamic-hypophyseal portal circulation, collects blood from capillaries originating in the hypothalamus and, through a plexus of veins surrounding the pituitary stalk, directs the blood into the anterior pituitary gland. This allows the neurohormones secreted by the neuroendocrine cells of the hypothalamus to be transported directly…

  • hypothalamic-pituitary-target organ axis (physiology)

    endocrine system: The hypothalamic-pituitary-target organ axis: The hypothalamic-pituitary-target organ axes of all vertebrates are similar. The hypothalamic neurosecretory system is poorly developed in the most primitive of the living Agnatha vertebrates, the hagfishes, but all of the basic rudiments are present in the closely related lampreys. In most…

  • hypothalamus (anatomy)

    Hypothalamus, region of the brain lying below the thalamus and making up the floor of the third cerebral ventricle. The hypothalamus is an integral part of the brain. It is a small cone-shaped structure that projects downward from the brain, ending in the pituitary (infundibular) stalk, a tubular

  • hypothallus (fungal structure)

    fungus: Form and function of lichens: Crustose lichens may have a hypothallus—i.e., an algal-free mat of hyphae extending beyond the margin of the regular thallus. Crustose form varies: granular types such as Lepraria, for example, have no organized thalloid structure; but some Lecanora species have highly organized thalli, with lobes that resemble foliose lichens lacking a…

  • hypothec (Roman law)

    Hypothec, in Roman law, a type of security for a debt in which the creditor had neither ownership nor possession. It arose in cases in which a renter needed the use of the things that he pledged as security for his continued payment of rent, usually tools or equipment necessary for working the

  • hypothermia (physiology)

    Hypothermia, abnormally low body temperature in a warm-blooded creature, associated with a general slowing of physiologic activity. Hibernating animals allow their body temperatures to fall to levels only slightly above ambient temperature, in a unique kind of hypothermia from which they can

  • Hypotheseis ton planomenon (work by Ptolemy)

    Ptolemy: Astronomer: …much as a later treatise, Hypotheseis tōn planōmenōn (Planetary Hypotheses). In this work he proposed what is now called the Ptolemaic system—a unified system in which each heavenly body is attached to its own sphere and the set of spheres nested so that it extends without gaps from Earth to…

  • hypothesis (logic)

    Hypothesis, something supposed or taken for granted, with the object of following out its consequences (Greek hypothesis, “a putting under,” the Latin equivalent being suppositio). In planning a course of action, one may consider various alternatives, working out each in detail. Although the word

  • Hypothesis Physica Nova (work by Leibniz)

    Gottfried Wilhelm Leibniz: Early life and education: …1671 under the general title Hypothesis Physica Nova (“New Physical Hypothesis”). He asserted that movement depends, as in the theory of the German astronomer Johannes Kepler, on the action of a spirit (God).

  • hypothesis testing (statistics)

    Hypothesis testing, In statistics, a method for testing how accurately a mathematical model based on one set of data predicts the nature of other data sets generated by the same process. Hypothesis testing grew out of quality control, in which whole batches of manufactured items are accepted or

  • hypothetical bias

    environmental economics: Sources of bias: …the respondent has no information), hypothetical bias (where the respondent will neither pay nor give a reasonable answer), starting-point bias (where the respondent is influenced by the initial numbers given as examples or as part of a range in survey), and strategic bias (where the respondent wants a specific outcome).…

  • hypothetical construct (psychology)

    Construct, in psychology, a tool used to facilitate understanding of human behaviour. All sciences are built on systems of constructs and their interrelations. The natural sciences use constructs such as gravity, temperature, phylogenetic dominance, tectonic pressure, and global warming. Likewise,

  • hypothetical imperative (philosophy)

    categorical imperative: …categorical as distinct from the hypothetical imperatives associated with desire, such as “Do not steal if you want to be popular.” For Kant there was only one such categorical imperative, which he formulated in various ways. “Act only according to that maxim by which you can at the same time…

  • hypothetical proposition (logic)

    categorical proposition: …connections, they contrast especially with hypothetical propositions, such as “If every man is mortal, then Socrates is mortal.”

  • hypothetical syllogism (logic)

    history of logic: Theophrastus of Eresus: …also credited with investigations into hypothetical syllogisms. A hypothetical proposition, for Theophrastus is a proposition made up of two or more component propositions (e.g., “p or q,” or “if p then q”), and a hypothetical syllogism is an inference containing at least one hypothetical proposition as a premise. The extent…

  • hypothetico-deductive method (philosophy)

    Hypothetico-deductive method, procedure for the construction of a scientific theory that will account for results obtained through direct observation and experimentation and that will, through inference, predict further effects that can then be verified or disproved by empirical evidence derived

  • hypothyroidism (pathology)

    Hypothyroidism, a deficiency in hormone production by the thyroid gland. Hypothyroidism usually results from a disorder of the thyroid gland, in which case it is described as primary hypothyroidism. Congenital primary hypothyroidism is caused by lack of or abnormal development of the thyroid in

  • hypotonia (pathology)

    cerebellar ataxia: Manifestations of ataxia and other symptoms: …may also show signs of hypotonia, or abnormally decreased muscle tone (e.g., floppier motions). Hypotonia, when present, is apparent only during the early phase of cerebellar disease.

  • hypotrich (protozoan)

    Hypotrich, any dorsoventrally flattened, oval protozoan of the ciliate order Hypotrichida, very widely distributed in both fresh and salt water. Instead of having simple cilia (hairlike processes), the hypotrichs have groups of fused cilia (cirri) arranged on the ventral surface and used for

  • hypotrichida (protozoan)

    Hypotrich, any dorsoventrally flattened, oval protozoan of the ciliate order Hypotrichida, very widely distributed in both fresh and salt water. Instead of having simple cilia (hairlike processes), the hypotrichs have groups of fused cilia (cirri) arranged on the ventral surface and used for

  • Hypotyposeis (work by Theognostus)

    Theognostus Of Alexandria: His principal work, the Hypotypōseis (Greek: “Outlines”), is a doctrinal compendium in seven books intended for use at the school.

  • hypoventilation syndrome (pathology)

    human respiratory system: Abnormal gas exchange: … are grouped into four categories—hypoventilation, shunting, ventilation–blood flow imbalance, and limitations of diffusion.

  • hypovitaminosis (pathology)

    nutritional disease: Vitamins: Although deficiency diseases have been described in laboratory animals and humans deprived of single vitamins, in human experience multiple deficiencies are usually present simultaneously. The eight B-complex vitamins function in coordination in numerous enzyme systems and metabolic pathways; thus, a deficiency of one may affect…

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