renal system: Arteries and arterioles: …afferent arteriole to become the efferent arterioles carrying blood away from the glomeruli. The afferent arterioles are almost twice as thick as the efferent arterioles because they have thicker muscular coats, but the sizes of their channels are almost the same.

nervous system: Nervous systems: …and sends an outgoing, or efferent, impulse to an efferent neuron, such as a motor neuron. The efferent neuron, in turn, makes contact with an effector such as a muscle or gland, which produces a response.

human sexual activity: Nervous system factors: …come from the cord (efferent nerves) transmitting impulses to activate muscles, and (2) the autonomic system, the primary function of which is the regulation and maintenance of the body processes necessary to life, such as heart rate, breathing, digestion, and temperature control. Sexual response involves the entire nervous system.…

nerve: …categories, namely, sensory (afferent) and motor (efferent). The fibres of these categories and their subdivisions constitute the functional components of the nerves. The combinations of such components vary in the individual cranial nerves; in the spinal nerves they are more uniform.

nervous system: Nervous systems: …or efferent, impulse to an efferent neuron, such as a motor neuron. The efferent neuron, in turn, makes contact with an effector such as a muscle or gland, which produces a response.

calcite: Chemical composition: …reaction is manifested by vigorous effervescence. (The dilution of the HCl usually used is about 90:10 [water:concentrated HCl].) The reactions involved are

Effi Briest, novel by Theodor Fontane, written in 1891–93; published in installments in the literary and political periodical Deutsche Rundschau from October 1894 to March 1895 and in book form in 1895. Known for its deft characterization and accurate portrayal of Brandenburg society, the novel

drug: Receptors: …to bind to a receptor; efficacy (sometimes called intrinsic activity) describes the ability of the drug-receptor complex to produce a physiological response. Together, the affinity and the efficacy of a drug determine its potency.

automobile: Transmission: The efficiency of an automobile engine is highest when the load on the engine is high and the throttle is nearly wide open. At moderate speeds on level pavement, the power required to propel an automobile is only a fraction of this. Under normal driving conditions…

efficiency, in economics and organizational analysis, a measure of the input a system requires to achieve a specified output. A system that uses few resources to achieve its goals is efficient, in contrast to one that wastes much of its input. Efficiency is a favourite objective of economists and

marketing: Efficiency control: Efficiency control involves micro-level analysis of the various elements of the marketing mix, including sales force, advertising, sales promotion, and distribution. For example, to understand its sales-force efficiency, a company may keep track of how many sales calls a representative makes each day,…

gerrymandering: …be represented as an “efficiency gap” between the parties when the difference between wasted votes is divided by the total number of votes cast. The plaintiffs argued that efficiency gaps of 7 percent or greater were legally significant because they were more likely than smaller gaps to persist through…

radiation measurement: Scintillators: …fraction is given the name scintillation efficiency and ranges from about 3 to 15 percent for common scintillation materials. The photon energy (or the wavelength of the light) is distributed over an emission spectrum that is characteristic of the particular scintillation material.

economics: Theory of allocation: …combination is called the “optimal” or “efficient” combination. As a rule, the optimal allocation equalizes the returns of the marginal (or last) unit to be transferred between all the possible uses. In the theory of the firm, an optimum allocation of outlays among the factors is the same for…

metaphysics: Aristotelianism: The notion of an efficient cause has a role in Aristotelianism. As Aristotle put it, it takes a human being, a developed specimen of the kind, to beget a human being. It is, however, a subordinate role and yields pride of place to a different idea—namely, form considered as…

rubber: The cure package: …is known as an “efficient vulcanization” (EV) system and gives products with sulfur interlinks of shorter length. EV products have improved resilience but lower strength.

economics: Financial economics: …changed understanding of the “efficient market hypothesis,” which held that securities prices in an efficient stock market were inherently unpredictable—that is, an investment in the stock market was, for all but insider traders, equivalent to gambling in a casino. (An efficient stock market was one in which all information…

Derek Jacobi: …Grace of Monaco (2014), and Effie Gray (2014). He reteamed with Branagh for the movie adaptations of Cinderella (2015) and Murder on the Orient Express (2017). In between the latter films, he reunited with the Cinderella cast onstage in Branagh’s production of Romeo and Juliet (2016).

crurotarsan: …that some forms, such as Effigia okeeffeae, were bipedal. (E. okeeffeae evolved some 80 million years before the first bipedal dinosaurs appeared.) Most crurotarsan lineages died out during the end-Triassic extinction event, and their demise has been attributed to a combination of volcanic eruptions and climatic changes. Furthermore, many

metalwork: England: There remain in England 10 effigies cast in bronze over a period of two centuries (1290–1518), among them some of the finest examples of figure work and metal casting to be found in Europe. In several instances, particulars for the contracts of the tombs survive, together with the names of…

mask: Funerary and commemorative uses: …revived in the making of effigy masks for the royalty and nobility of Europe from the late Middle Ages through the 18th century. Painted and with human hair, these masks were attached to a dummy dressed in state regalia and were used for display, processionals, or commemorative ceremonies.

effigy mound, earthen mound in the form of an animal or bird found throughout the north-central United States. Prehistoric Native Americans built a variety of earth berm structures in addition to effigy mounds, including conical, linear, and flat-topped mounds. Although other mound forms preceded

Effigy Mounds National Monument, area of 4 square miles (10 square km) containing numerous ancient Native American burial and ceremonial mounds in northeastern Iowa, U.S., on the Mississippi River, a few miles north of McGregor. Established in 1949 and located on bluffs overlooking the river, the

Effingham, city, seat (1860) of Effingham county, east-central Illinois, U.S. It lies near the Little Wabash River, about 65 miles (105 km) southeast of Decatur. Settled about 1814 by farmers, the community grew slowly as pioneers moved westward along the Cumberland (National) Road, which had been

massage: …light or hard stroking (effleurage), which relaxes muscles and improves circulation to the small surface blood vessels and is thought to increase the flow of blood toward the heart; compression (petrissage), which includes kneading, squeezing, and friction and is useful in stretching scar tissue, muscles, and tendons so that…

efflorescence, spontaneous loss of water by a hydrated salt, which occurs when the aqueous vapor pressure of the hydrate is greater than the partial pressure of the water vapour in the air. For example, because the vapour pressures of washing soda (Na2CO3·10H2O) and Glauber’s salt (Na2SO4·10H2O)

mining: Evaporation of effluents: Increasing attention has been devoted to the extraction of salts from brines discharged as effluent after the distillation of fresh water from seawater. By using these brines for the extraction of minerals, several important advantages are gained. First, the cost of pumping is carried…

wastewater treatment: Effluent polishing: For the removal of additional suspended solids and BOD from secondary effluent, effluent polishing is an effective treatment. It is most often accomplished using granular media filters, much like the filters used to purify drinking water. Polishing filters are usually built as prefabricated…

wastewater treatment: Wastewater treatment and disposal: Effluent standards, on the other hand, pertain directly to the quality of the treated wastewater discharged from a sewage treatment plant. The factors controlled under these standards usually include biochemical oxygen demand (BOD), suspended solids, acidity, and coliforms.

electromagnetism: Emergence of the modern sciences of electricity and magnetism: …which then left an “effluvium,” or atmosphere, around the body. The language is quaint, but, if the “humour” is renamed “charge” and the “effluvium” renamed “electric field,” Gilbert’s notions closely approach modern ideas.

electromagnetism: Emergence of the modern sciences of electricity and magnetism: …which then left an “effluvium,” or atmosphere, around the body. The language is quaint, but, if the “humour” is renamed “charge” and the “effluvium” renamed “electric field,” Gilbert’s notions closely approach modern ideas.

Effon-Alaiye, town, Ekiti state, southwestern Nigeria, in the Yoruba Hills, at the intersection of roads from Ilesha, Ondo, and Ado-Ekiti. It was probably founded in the late 19th century, when both the Ilesha and Effon belonged to the Ekiti–Parapo, a Yoruba confederation that fought against the

French literature: Drama: …the corruption of financiers in Les Effrontés (1861; “The Shameless Ones”) is as trenchant as comparable portraits in the Naturalist novelists.

gas: Effusion: Consider the system described above in the calculation of gas pressure, but with the area A in the container wall replaced with a small hole. The number of molecules that escape through the hole in time t is equal to (1/2)(N/V)vz(At). In this case,…

volcano: Two 20th-century eruptions: …of Mauna Loa (illustrative of effusive volcanism).

Efik, people inhabiting the lower Cross River in Cross River state, Nigeria. Their language is the main dialect and language of the Efik-Ibibio group of the Benue-Congo branch of Niger-Congo languages. It is widely spoken as a lingua franca throughout the Cross River region. The Efik, who are

Efik: …dialect and language of the Efik-Ibibio group of the Benue-Congo branch of Niger-Congo languages. It is widely spoken as a lingua franca throughout the Cross River region. The Efik, who are culturally and linguistically related to the Ibibio, migrated down the Cross River during the first half of the 17th…

English Football League (EFL), English professional football (soccer) organization. The league was formed in 1888, largely through the efforts of William McGregor, known afterward as the “father of the league.” Twelve of the strongest professional clubs of the time joined in the league, and the

Walachia, principality on the lower Danube River, which in 1859 joined Moldavia to form the state of Romania. Its name is derived from that of the Vlachs, who constituted the bulk of its population. Walachia was bounded on the north and northeast by the Transylvanian Alps, on the west, south, and

eflornithine, drug used to treat late-stage African trypanosomiasis (sleeping sickness). Eflornithine is effective only against Trypanosoma brucei gambiense, which causes Gambian (or West African) sleeping sickness. It is not effective against T. brucei rhodesiense, which causes Rhodesian (or East

ephod, part of the ceremonial dress of the high priest of ancient Israel described in the Old Testament (Ex. 28:6–8; 39:2–5). It was worn outside the robe and probably kept in place by a girdle and by shoulder pieces, from which hung the breast piece (or pouch) containing the sacred lots

Profiat Duran was a Jewish philosopher and linguist, the author of a devastating satire on medieval Christianity and of a notable work on Hebrew grammar. Duran was the descendant of a scholarly Jewish family of southern France. He was educated in Germany and then took a position as tutor with a

Profiat Duran was a Jewish philosopher and linguist, the author of a devastating satire on medieval Christianity and of a notable work on Hebrew grammar. Duran was the descendant of a scholarly Jewish family of southern France. He was educated in Germany and then took a position as tutor with a

Effon-Alaiye, town, Ekiti state, southwestern Nigeria, in the Yoruba Hills, at the intersection of roads from Ilesha, Ondo, and Ado-Ekiti. It was probably founded in the late 19th century, when both the Ilesha and Effon belonged to the Ekiti–Parapo, a Yoruba confederation that fought against the

improvised explosive device: Components: …some Shīʿite militia groups used explosively formed projectiles (EFPs)—an extremely lethal form of shaped charge supplied by Iran—to destroy even the most heavily armoured vehicles, such as M1 Abrams tanks.

ifrit, in Islamic mythology and folklore, a class of powerful malevolent supernatural beings. The exact meaning of the term ifrit in the earliest sources is difficult to determine. It does not occur in pre-Islamic poetry and is only used once in the Qurʾān, in the phrase “the ifrit of the jinn”

Marina Ivanovna Tsvetayeva was a Russian poet whose verse is distinctive for its staccato rhythms, originality, and directness and who, though little known outside Russia, is considered one of the finest 20th-century poets in the Russian language. Tsvetayeva spent her youth predominantly in Moscow,

Who were the Von Erich wrestling family?: Kevin Von Erich (1957– ): …by Sean Durkin and starring Zac Efron, Jeremy Allen White, and Harris Dickinson as Kevin, Kerry, and David Von Erich, respectively.

Slovakia: History of Slovakia: …over the expansion of the European Financial Stability Facility (EFSF), the euro zone’s primary bailout mechanism, toppled the Radičová government. After the government’s collapse, Radičová opened talks with Smer, and Fico pledged his support for the EFSF in exchange for early elections.

money: Electronic money: First, depositors can use electronic funds transfers (EFTs) to withdraw currency from their accounts using automated teller machines (ATMs). In this way an ATM withdrawal works like a debit card. ATMs also allow users to deposit checks into their accounts or repay bank loans. While they do not replace…

European Free Trade Association (EFTA), group of four countries—Iceland, Liechtenstein, Norway, and Switzerland—organized to remove barriers to trade in industrial goods among themselves, but with each nation maintaining its own commercial policy toward countries outside the group. Headquarters are

Dan Andersson: …published after his death in Efterskörd (1929; “Late Harvest”) and Tryckt och otryckt (1942; “Printed and Unprinted”).

Peter Seeberg: …Seeberg’s collection of short stories, Eftersøgningen (1962; “The Search”). These characters act but lack all awareness of the motives of their actions.

Bulgarian Orthodox Church: …Turks (1393), the last patriarch, Eftimi, was exiled and the patriarchate ceased to exist. For nearly five centuries Bulgaria was under Turkish domination, and the church was administered by the patriarch of Constantinople through a Greek clergy. The struggle for an independent Bulgarian church, begun late in the 18th century,…

African literature: English: Flora Nwapa wrote the novel Efuru (1966), the story of a talented, brilliant, and beautiful woman who, living in a small community, is confined by tradition. A woman’s fundamental role, childbearing, is prescribed for her, and if she does not fulfill that role she suffers the negative criticism of members…

stem cell: Embryonic germ cells: Embryonic germ (EG) cells, derived from primordial germ cells found in the gonadal ridge of a late embryo, have many of the properties of embryonic stem cells. The primordial germ cells in an embryo develop into stem cells that in an adult…

Tefé, city and river port, central Amazonas estado (state), northwestern Brazil. Founded by missionaries as Nogueira in the 17th century and also called Ega at one time, Tefé lies on the left (north) bank of the portion of the Amazon River known as the Solimões, on the lake formed by the mouth of

Egadi Islands, small mountainous group of islets belonging to Italy, in the Mediterranean just off the western coast of Sicily, with a total area of 15 square miles (39 square km). The principal islands are Favignana, the largest (7 square miles [18 square km]), Levanzo, and Marettimo. In the

keffiyeh: Variations: …thick black cord called the ʿiqāl is tied around the ghutrah to secure it to the head. This variation is worn primarily in the Gulf States, including Bahrain, Qatar, and the United Arab Emirates. In Iran the chafiyeh is worn atop the head and is typically checkered in a dark…

egalitarianism, the belief in human equality, especially political, social, and economic equality. Egalitarianism has been a driving principle of many modern social movements, including the Enlightenment, feminism, civil rights efforts, and the establishment of international human rights. Given

Jennifer Egan is an American novelist and short-story writer whose diverse works have garnered great critical acclaim. Egan was born in Chicago but grew up in San Francisco. She attended the University of Pennsylvania and then went to England to study at St. John’s College, Cambridge. During this

Pierce Egan, the Elder was a sporting writer whose works were considered indispensable reading for English men-about-town in the early 19th century. Egan made his reputation as a boxing reporter. His best-known work is Boxiana (1818–24), a racy but accurate account of the lives of famous pugilists.

Terrassa, city, Barcelona provincia (province), in the comunidad autónoma (autonomous community) of Catalonia, in northeastern Spain. Terrassa lies along the coastal plain, just northwest of Barcelona city. The successor of Egara, a Roman town, it became in ad 450 an important episcopal see with a

António Egas Moniz was a Portuguese neurologist and statesman who was the founder of modern psychosurgery. With Walter Hess he was awarded the 1949 Nobel Prize for Physiology or Medicine for the development of prefrontal leucotomy (lobotomy) as a radical therapy for certain psychoses, or mental

Abeokuta: …hunter and leader of the Egba refugees who fled from the disintegrating Oyo empire. The town was also settled by missionaries (in the 1840s) and by Sierra Leone Creoles, who later became prominent as missionaries and as businessmen. Abeokuta’s success as the capital of the Egba and as a link…

Yoruba: …of voluntary associations, including the egbe, a male recreational association; the aro, a mutual-aid association of farmers; and the esusu, whose members contribute a fixed amount of money and from which they can receive loans. Political authority is vested in the oba and a council of chiefs; constituent towns each…

Obafemi Awolowo: …while there he founded the Egbe Omo Oduduwa (Yoruba: “Society of the Descendants of Oduduwa”) to promote the culture and unity of the Yoruba people, one of the three largest ethnic groups in colonial Nigeria, and to ensure a secure future for them. During that period Awolowo also wrote the…

Egbert was the king of the West Saxons from 802 to 839, who formed around Wessex a kingdom so powerful that it eventually achieved the political unification of England (mid-10th century). The son of Ealhmund, king in Kent in 784 and 786, Egbert was a member of a family that had formerly held the

Ekoi: …of British colonial administration, the egbo was a prominent Ekoi secret society that had strong social regulatory functions as well as influence in religious matters. Members of the egbo used a form of ideographic writing called nsibidi, variations of which were formerly found among other ethnic groups in southeastern Nigeria.

Calabar: …of Old Calabar by the Ekpe secret society, which was controlled by the towns’ merchant houses.

esophagogastroduodenoscopy (EGD), diagnostic procedure in which an endoscope is passed through the esophagus, stomach, and duodenum in order to visually examine the tissues for evidence of disease. The flexible fibre-optic endoscope contains special channels, which facilitate biopsy, and usually

Aegean Sea, an arm of the Mediterranean Sea located between the Greek peninsula on the west and Asia Minor on the east. About 380 miles (612 km) long and 186 miles (299 km) wide, it has a total area of some 83,000 square miles (215,000 square km). The Aegean is connected through the straits of the

Eskimo-Aleut languages: Alphabets and orthography: …was published in 1742 by Hans Egede, a Dano-Norwegian missionary to Greenland. It was printed in the current Roman alphabet.

Greenland: History of Greenland: IA leader Múte Bourup Egede became prime minister, the steward of IA-Naleraq majority coalition government that was supported by Atassut.

Jan Egeland is a Norwegian public official who served as head of United Nations (UN) humanitarian and relief efforts from 2003 to 2006. Egeland earned a bachelor’s degree in political science from the University of Oslo (1982) and studied as a Fulbright scholar at the University of California,

rederijkerskamer: The Egelantier (Dutch: Wild Briar) and the Wit Lavendel (Dutch: White Lavender), however, remained popular into the 17th century because of the leading Renaissance poets associated with them in Amsterdam.

Western sculpture: Central Europe: Paul Egell was a pupil of Permoser in Dresden at the time of the Zwinger decorations, and in 1721 he was appointed court sculptor at Mannheim. Egell’s elongated and refined Baroque figures were an effective counter to the Classicism of Donner, and his personality was…

The Comedy of Errors: Egeon, a merchant of Syracuse, is arrested in Ephesus because of hostilities between the two cities and, unable to pay the local ransom, is condemned to death. He tells the duke, Solinus, his sad tale: years earlier he and his wife had been shipwrecked with…

Cheb, city, extreme western Czech Republic. Cheb lies along the Ohře River, near the German border. Its history has been full of violence, for it guards the easiest approach to Bohemia from the northwest. The city passed in the 13th century from Swabian rulers to Otakar I, king of Bohemia, and it

Eger, city of county status and seat of Heves megye (county), northern Hungary. It lies in the valley of the Eger River, which is a tributary of the Tisza, between the Mátra and Bükk mountains. Eger is an old Magyar tribal city with a bishopric founded in the 11th century. The Tatar invasion of the

Ohře River, tributary of the Elbe River, rising in the Fichtel Mountains (Fichtelgebirge) of Germany and flowing generally east and northeastward into the Czech Republic past Cheb, Karlovy Vary, Žatec, and Louny until it reaches the Elbe (Labe) River opposite Litoměřice. The river is 196 miles (316

Germany: Wenceslas: At the Diet of Eger (May 2) he ordered them to desist and declared the city leagues to be dissolved. The contestants complied. The princes were satisfied with the prospective disbandment of the cities, and the cities feared the consequences of further resistance, but neither side relished…

Sarah Helen Whitman was an American poet and essayist, noted for her literary criticism and perhaps best remembered for her alliance with and scholarly defense of Edgar Allan Poe. Sarah Power from an early age was an avid reader of novels and of poetry, especially that of Lord Byron. In 1828 she

Egeria, in Roman religion, a water spirit worshiped in connection with Diana at Aricia and also with the Camenae in their grove outside the Porta Capena at Rome. Like Diana, she was a protectress of pregnant women and, like the Camenae, was considered prophetic. Traditionally she was the wife, or

Elodea: Brazilian elodea (Egeria densa; formerly Elodea densa) and Canadian waterweed are commonly used in schools as an experimental plant for demonstrating cellular structures, such as chloroplasts and nuclei, and oxygen production during photosynthesis. Those and other species are also economically important as aquarium plants, where…

Krisztina Egerszegi is a Hungarian swimmer, the youngest athlete ever to win an Olympic gold medal in swimming. She won the 200-metre backstroke at the 1988, 1992, and 1996 Olympic Games, becoming only the second swimmer (after Dawn Fraser) to win an individual event at three Olympiads. In 1987

Nakuru: …centre and the site of Egerton University (1939). It is a busy commercial and transport centre for west-central Kenya. Nearby attractions include Lake Nakuru National Park, known for its hundreds of species of birds, the Hyrax Hill prehistoric site, and the immense Menengai Crater. Pop. (1999) 219,366; (2009) 286,411.

Ellesmere Island: …coast in the Isabel) for Francis Egerton, 1st Earl of Ellesmere.

Francis Egerton, 3rd duke of Bridgewater was the founder of British inland navigation, whose canal, built from his estates at Worsley to the city of Manchester, is called the Bridgewater Canal. His father, who was created duke in 1720, was the great-great-grandson of Lord Chancellor Ellesmere.

Thomas Egerton, Viscount Brackley was an English lawyer and diplomat who secured the independence of the Court of Chancery from the common-law courts, thereby formulating nascent principles of equitable relief. Educated at Brasenose College, Oxford, and called to the bar by Lincoln’s Inn in 1572,

Funen: Two of the finest are Egeskov (1554) and Brahetrolleborg (1568; incorporating parts of a monastery founded in 1172), both in the south. The island’s chief ports are the manufacturing city of Odense, Assens, Svendborg, Nyborg, Kerteminde, Middelfart, and Fåborg. Area 1,152 square miles (2,984 square km). Pop. (2003 est.) 441,795.

Segesta, ancient city of Sicily, located on Monte Barbaro about 2 miles (3 km) northwest of modern Calatafimi. It was the chief city of the Elymi, a people for whom Thucydides claimed a Trojan origin; they are archaeologically indistinguishable in the Early Iron Age (c. 1000–c. 500 bc) from their

digestion: Egestion: Animals that ingest bulk food unavoidably take in some matter that they are incapable of using. In the case of unicellular organisms that form food vacuoles, the vacuoles eventually fuse with the cell membrane and then rupture, releasing indigestible wastes to the outside. Substances…

Stanley Cohen: Cohen termed this substance epidermal growth factor (EGF), and he went on to purify it and completely analyze its chemistry. He and his coworkers found that EGF influences a great range of developmental events in the body. He also discovered the mechanisms by which EGF is taken into and…

macular degeneration: Other forms of macular degeneration: …by mutations in the gene EFEMP1 (EGF-containing fibulin-like extracellular matrix protein 1). Sorsby fundus dystrophy, which is clinically similar to wet AMD, is caused by mutations in a gene known as TIMP3 (tissue-inhibitor of metalloproteinase 3). These forms of macular degeneration, with the exception of Stargardt macular dystrophy, are inherited…

pancreatic cancer: Treatment: …of enzyme) associated with the epidermal growth factor receptor (EGFR), which stimulates unregulated cell division when mutated in cancer cells. When erlotinib is given in combination with the chemotherapeutic agent gemcitabine (Gemzar), an antimetabolite that inhibits the synthesis of genetic material in dividing cells, patient survival is improved, although only…

Ecgfrith was an Anglo-Saxon king of the Northumbrians from 670 who ultimately lost his wars against the Mercians on the south and the Picts on the north. Ecgfrith was the son of King Oswiu and nephew of St. Oswald and a generous supporter of his kingdom’s great monasteries. By 674 he defeated a

egg, the content of the hard-shelled reproductive body produced by a bird, considered as food. While the primary role of the egg obviously is to reproduce the species, most eggs laid by domestic fowl, except those specifically set aside for hatching, are not fertilized but are sold mainly for human

egg, in biology, the female sex cell, or gamete. In botany, the egg is sometimes called a macrogamete. In zoology, the Latin term for egg, ovum, is frequently used to refer to the single cell, while the word egg may be applied to the entire specialized structure or capsule that consists of the

egg: Structure and composition: The structural components of the egg include the shell and shell membranes (10 percent); the albumen or white (60 percent), including the thick albumen, the outer thin albumen, the inner thin albumen, and the chalazae; and the yolk (30 percent). In a fertilized egg, the yolk supplies the nutrients and…