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Occlusive strokes, those in which a blood vessel supplying a part of the brain is blocked, are divided into four groups: (1) Transient ischemic attacks (TIAs) are the mildest occlusive strokes; symptoms last for minutes or hours. TIAs are usually caused by small emboli, such as fragments composed of blood cells or cholesterol, that are swept into the circulation of the brain from the arteries......

...the growing grains are extremely difficult to eliminate, no matter how long the object is sintered. For this reason sintering aids are often used to enhance the sintering of advanced ceramics. In reactive-liquid, or transient-liquid, sintering, a chemical additive produces a temporary liquid that facilitates the initial stages of sintering. The liquid is subsequently evaporated, resorbed by......

...that results in thickened blood, retarded flow, and an increased danger of clot formation within the circulatory system. Polycythemia may be relative (e.g., after blood-plasma loss), transient (as when a large number of red blood cells suddenly enter the circulation from storage), or absolute (i.e., reflecting an increase in actual mass of red cells in the body). Relative......

Prominences vary considerably in size, shape, and motion and are of two main types, active and quiescent. Active prominences erupt quickly and have lifetimes lasting from several minutes to a few hours. They are associated with sunspot groups and, like these, are correlated in numbers and activity with the solar cycle. Quiescent prominences tend to emerge smoothly and subside much more slowly,......

Consider a circuit consisting of a capacitor and a resistor that are connected as shown in Figure 19. What will be the voltage at point b if the voltage at a is increased suddenly from Va = 0 to Va = +50 volts? Closing the switch produces such a voltage because it connects the positive terminal of a 50-volt battery to point......

Prominences vary considerably in size, shape, and motion and are of two main types, active and quiescent. Active prominences erupt quickly and have lifetimes lasting from several minutes to a few hours. They are associated with sunspot groups and, like these, are correlated in numbers and activity with the solar cycle. Quiescent prominences tend to emerge smoothly and subside much more slowly,......

...then force the air stream back and forth across the edge, reinforcing the vibration at the resonant frequency of the tube. The time required to set up this steady-state oscillation is called the transient time of the instrument. The human ear is extremely sensitive to transients in musical tones, and such transients are crucial to the identification of various musical instruments whose......

...generators big enough to drive the pumps and a battery supply sufficient to run the instruments. The risk would be that of the emergency generators not accepting load when they are started up. In transient without scram, the event is insertion of reactivity, for example, by an unchecked withdrawal of shim rods. The protective response is the rapid and automatic insertion of the safety rods.......

historic eastern European region. After forming part of Hungary (11th–16th century), it was an autonomous principality within the Ottoman Empire (16th–17th century) and then once again became part of Hungary at the end of the 17th century; later it was incorporated into Romania (1918–20). The region, whose name first appeared in written documents in the 12th...

...following the line of a tectonic dislocation, or zone of shattering in the Earth’s crust, parallel with this part of the mountains. Between this volcanic range and the South Carpathian Block, the Transylvanian Plateau spreads out, filled with loose rock formations of young Tertiary age....

semiconductor device for amplifying, controlling, and generating electrical signals. Transistors are the active components of integrated circuits, or “microchips,” which often contain millions of these minuscule devices etched into their shiny surfaces. Deeply embedded in almost everything electronic, transistors have become the nerve cells of th...

This watershed agreement led to Totsuko’s first hugely successful product line: transistor radios. Although Texas Instruments Incorporated was first to market with its Regency transistor radio in 1955, it was Sony’s TR-63, an inexpensive shirt-pocket-sized all-transistor radio, that caught consumers’ attention when it was released in 1957. Sony’s pocket radios were a tr...

any of the first series of U.S. navigation satellites. Launched by the U.S. Navy in 1960–61, the Transit satellites were developed to provide an accurate, all-weather navigational aid for seagoing vessels (including submarines) and aircraft. The system was so designed that any such craft could pinpoint its position by using a computer specially programmed to translate co...

...a tripod with adjustable legs, the theodolite is used in the field to obtain precise angular measurements for triangulation in road building, tunnel alignment, and other civil-engineering work. The transit is a variety of theodolite that has the telescope so mounted that it can be completely reversed, or transited. The phototheodolite, a combination camera and theodolite mounted on the same......

in astronomy, the passage of a relatively small body across the disk of a larger body, usually the Sun or a planet, occulting only a very small area. Mercury and Venus periodically transit the Sun, and a satellite may transit its planet. Compare eclipse....

...of the skin, the lining of the small intestine, and bone marrow, undergo continuous cellular turnover. They contain stem cells, which persist indefinitely, and a much larger number of “transit amplifying cells,” which arise from the stem cells and divide a finite number of times until they become differentiated. The stem cells exist in niches formed by other cells, which......

There are four main types of buses: city or transit, suburban, intercity or tour, and school. The city bus operates within the city limits and is characterized by low maximum speed, low-ride platform, provision for standing and wheelchair passengers, two entrances on the curb side, low-back seats, and no luggage space. The suburban bus is designed for short intercity runs and has high-back......

...his meridian. The latter process is referred to as transiting the meridian, from which the name of the telescope is derived. There are various types of transit instruments, as, for example, the transit circle telescope, the vertical circle telescope, and the horizontal meridian circle telescope. The transit circle determines the right ascension of celestial objects, while the vertical......

...tariffs—unless they are so high as to keep out imports—yield revenue, while revenue tariffs give some protection to any domestic producer of the duty-bearing goods. A transit duty, or transit tax, is a tax levied on commodities passing through a customs area en route to another country. Similarly, an export duty, or export tax, is a tax imposed on commodities leaving a customs......

...otherness of Tasmania in The Doubleman (1985) and Out of Ireland (1999). Likewise, Shirley Hazzard wrote with great seriousness of purpose in her modern tragedy The Transit of Venus (1980), an ironic love story devised to contemplate how strangely things come about. Like so much of Australian fiction, it looks for patterns of meaning that might......

...tariffs—unless they are so high as to keep out imports—yield revenue, while revenue tariffs give some protection to any domestic producer of the duty-bearing goods. A transit duty, or transit tax, is a tax levied on commodities passing through a customs area en route to another country. Similarly, an export duty, or export tax, is a tax imposed on commodities leaving a customs......

German maker of astronomical instruments who introduced the meridian, or transit, circle, a specially designed telescope for measuring both the time when a celestial body is directly over the meridian (the longitude of the instrument) and the angle of the body at meridian passage. By 1796 he was engaged in the construction of a dividing engine, a machine used to mark off equal intervals......

American founders, with Elliot Paul, of the revolutionary literary quarterly transition....

alteration of a physical system from one state, or condition, to another. In atomic and particle physics, transitions are often described as being allowed or forbidden (see selection rule). Allowed transitions are those that have high probability of occurring, as in the case of short-lived radioactive decay of atomic nuclei. In three-millionths of a se...

In East Africa in the 1960s, written literature was only just coming to birth; and the literary review Transition (Kampala, Uganda, 1961–68) played an important part in encouraging young writers. In the late 1960s the most original talent in East Africa was that of a Ugandan, Okot p’Bitek, whose long poem Song of Lawino (196...

any of various chemical elements that have valence electrons—i.e., electrons that can participate in the formation of chemical bonds—in two shells instead of only one. While the term transition has no particular chemical significance, it is a convenient name by which to distinguish the similarity of the atomic structures and resulting properties of ...

...the proton is substantially constant, and the region of stable phase is on the falling side of the voltage curve, as it is in a synchrocyclotron. At the point that divides these regions, called the transition energy, there is no phase stability. At Brookhaven a model electron accelerator was built to demonstrate that the beam could be accelerated through the transition energy in a stable......

any of various chemical elements that have valence electrons—i.e., electrons that can participate in the formation of chemical bonds—in two shells instead of only one. While the term transition has no particular chemical significance, it is a convenient name by which to distinguish the similarity of the atomic structures and resulting properties of ...

...to know the entire history of the process than it is to know only its current state. The conditional distribution of X(t + h) given X(t) is called the transition probability of the process. If this conditional distribution does not depend on t, the process is said to have “stationary” transition probabilities. A Markov proces...

...the latter two intervals. On average, Mercury transits the Sun about 13 times per century. In the transit of Mercury that took place on Nov. 15, 1999, the planet just grazed the edge of the Sun. The Transition Region and Coronal Explorer (TRACE) satellite, an Earth-orbiting solar observatory launched in 1998, recorded the event in several wavelengths (see the photo). Mercury’s dar...

a conception of chemical reactions or other processes that involve rearrangement of matter as proceeding through a continuous change in the relative positions and potential energies of the constituent atoms and molecules. Between the initial and final arrangements of atoms or molecules there exists an intermediate configuration for which the energy arising from interatomic and i...

complete disappearance of electrical resistance in various solids when they are cooled below a characteristic temperature. This temperature, called the transition temperature, varies for different materials but generally is below 20 K (−253 °C)....

...Plateau is marked by a series of giant escarpments known collectively as the Mogollon Rim. West and south of the rim, a number of streams follow narrow canyons or broad valleys south through the Transition Zone and into the Basin and Range Province. The Transition Zone bordering the plateaus comprises separated plateau blocks, rugged peaks, and isolated rolling uplands so forbidding that......

...foothills, and valleys above 4,500 feet, is a region of prairie grasses, low piñon pines, and juniper shrubs. At higher altitudes, better stands reflect the more abundant rainfall. The Transition Zone, covering some 19,000 square miles, is identified chiefly by the ponderosa pine. The Canadian Zone, covering 4,000 square miles at elevations of 8,500 to 9,500 feet, contains blue......

In transitional activity, another type of conflict resolution, the animal is stimulated to perform a particular behaviour, but the required environmental stimulus becomes unavailable during the course of the response. The animal discontinues its initial behaviour and substitutes another behaviour that it initially had not “intended” to perform....

Dialectologists often distinguish between focal areas—which provide sources of numerous important innovations and usually coincide with centres of lively economic or cultural activity—and relic areas—places toward which such innovations are spreading but have not usually arrived. (Relic areas also have their own innovations, which, however, usually extend over a smaller......

...(PDG). In April 1984, after Touré’s death, a military group abolished the PDG and all associated revolutionary committees and replaced them with the Military Committee for National Recovery (CMRN). A new constitution in 1991 began a transition to civilian rule. Political parties were legalized in 1992, and Guinea’s first multiparty elections were held in 1993. The constitut...

In stratified ciliated epithelium the superficial cells are ciliated and columnar. This epithelium lines parts of the respiratory passages, the vas deferens, and the epididymis. Transitional epithelium lines the urinary bladder; its appearance depends upon whether the bladder is contracted or distended. ...

in mathematics and logic, statement that if A bears some relation to B and B bears the same relation to C, then A bears it to C. In arithmetic, the property of equality is transitive, for if A = B and B = C, then A = C. Likewise is the property inequality if the two inequalities have the same se...

in mathematics and logic, statement that if A bears some relation to B and B bears the same relation to C, then A bears it to C. In arithmetic, the property of equality is transitive, for if A = B and B = C, then A = C. Likewise is the property inequality if the two inequalities have the same se...

...they may be used in combination with a following member of B, cannot occur alone (cf. “enjoyed”). The question is whether one respects the traditional distinction between transitive and intransitive verb forms. It may be decided, then, that “lost,” “stole,” “ate” and so forth belong to one class, C (the class to which....

in mathematics and logic, statement that if A bears some relation to B and B bears the same relation to C, then A bears it to C. In arithmetic, the property of equality is transitive, for if A = B and B = C, then A = C. Likewise is the property inequality if the two inequalities have the same se...

Arab country of Southwest Asia, in the rocky desert of the northern Arabian Peninsula....

...Epoch (23.8 to 5.3 million years ago), as the Arabian tectonic plate collided with the Eurasian plate to the north, upheaval of the seabed produced the upfolded structures of the Transjordanian highlands and the central range of Palestine, causing the fractures that allowed the Dead Sea graben to drop. At that time, the Dead Sea was probably about the size that it is today......

former republic (though never internationally recognized as such) and Bantustan in southern Africa. It lay along the Indian Ocean and was surrounded mainly by the Republic of South Africa, though to the north it also touched Lesotho. Transkei consisted of three separate land units, two much smaller than the third. The capital was at Umtata....

Accompanying Moscow’s rise were a series of writings on the theme of translatio imperii (“translation of empire”), which constructed genealogies and described the transmission of imperial and ecclesiastical regalia to Russia. Particularly important is the monk Philotheus’ (Filofei’s) epistle to Vasily III (written between 1514 and 1521), which proclaimed t...

The period of greatest interest in computational linguistics was from about 1955 to 1965, when researchers undertook projects that would lead to computerized or mechanical translation involving grammatical and semantic analysis of sentences. Support for research in mechanical translation diminished after it became apparent that the problem of producing automatic translations of high quality was......

in physics, change with time of the position or orientation of a body. Motion along a line or a curve is called translation. Motion that changes the orientation of a body is called rotation. In both cases all points in the body have the same velocity (directed speed) and the same acceleration (time rate of change of velocity). The most general kind of motion combines both translation and......

The general motion of a rigid body tumbling through space may be described as a combination of translation of the body’s centre of mass and rotation about an axis through the centre of mass. The linear momentum of the body of mass M is given by...

The process of translation requires the interaction not only of large numbers of proteinaceous translational factors but also of specific membranes and organelles of the cell. In both prokaryotes and eukaryotes, translation takes place on cytoplasmic organelles called ribosomes. Ribosomes are aggregations of many different types of proteins and ribosomal RNA (rRNA). They can be thought of as......

...number of elements of symmetry; i.e., changes in the orientation of the arrangement of atoms seem to leave the atoms unmoved. One such element of symmetry is rotation; other elements are translation, reflection, and inversion. The elements of symmetry present in a particular crystalline solid determine its shape and affect its physical properties....

...one of the main contributors to the Tory-oriented Edinburgh Monthly Magazine (later Blackwood’s Edinburgh Magazine) from the time of its founding in 1817. With others, he wrote the “Translation from an Ancient Chaldee Manuscript,” which lampooned Scottish celebrities in a parody of Old Testament style; this article made Blackwood’s an immediate s...

Every gas molecule moves in three-dimensional space, and this translational motion contributes (3/2)RT (per mole) to the internal energy E. For monatomic gases, such as helium, neon, argon, krypton, and xenon, this is the sole energy contribution. Gases that contain two or more atoms per molecule also contribute additional terms because of their internal motions:...

Atomic positions in a crystal exhibit a property called long-range order or translational periodicity; positions repeat in space in a regular array, as in Figure 2A. In an amorphous solid, translational periodicity is absent. As indicated in Figure 2B, there is no long-range order. The atoms are not randomly distributed in space, however, as they are in the gas in Figure 2C. In the glass......

Rockslides and other types of slides involve the displacement of material along one or more discrete shearing surfaces. The sliding can extend downward and outward along a broadly planar surface (a translational slide), or it can be rotational along a concave-upward set of shear surfaces (a slump). A translational slide typically takes place along structural features, such as a bedding plane or......

...partition to modern Irish self-perception and self-representation. Friel, already established as Ireland’s leading playwright, wrote and in 1980 produced Field Day’s landmark play Translations; it is set in mid-19th-century Donegal, where British Ordnance Survey engineers are remapping and translating the Irish landscape into English. The play’s per...

...program determines which user program is to be executed next. Certain operating-system programs, however, may operate as independent units to facilitate the programming process. These include translators (either assemblers or compilers), which transform an entire program from one language to another; interpreters, which execute a program sequentially, translating at each step; and......

Separate transliteration tables for Classical and Modern Greek accompany this article. Some differences in transliteration result from changes in pronunciation of the Greek language; others reflect convention, as for example the χかい (chi or khi), which was transliterated by the Romans as ch (because they lacked the letter k in their usual alphabet). In Modern......

Separate transliteration tables for Classical and Modern Greek accompany this article. Some differences in transliteration result from changes in pronunciation of the Greek language; others reflect convention, as for example the χかい (chi or khi), which was transliterated by the Romans as ch (because they lacked the letter k in their usual alphabet). In Modern.........

...can be duplicated three (triploidy) or more (polyploidy) times; or one arm or part of one arm of a single chromosome may be missing (deletion). Part of one chromosome may be transferred to another (translocation), which has no effect on the person in which it occurs but generally causes a deletion or duplication syndrome in his or her children. Changes in chromosome number occur during sperm or...

...nonoverlapping action, the film contains an early example of parallel editing, two credible back, or rear, projections (the projection from the rear of previously filmed action or scenery onto a translucent screen to provide the background for new action filmed in front of the screen), two camera pans, and several shots composed diagonally and staged in depth—a major departure from the.....

in religion and philosophy, rebirth of the soul in one or more successive existences, which may be human, animal, or, in some instances, vegetable. While belief in reincarnation is most characteristic of Asian religions and philosophies, it also appears in the religious and philosophical thought of primitive religions, in some ancient Middle Eastern religions (e.g., the G...

...frequency, or phase—are modified by another wave in such a manner that the original wave becomes a “carrier,” bearing the recognizable imprint of the modifying wave. In the transmission of data signals over the PSTN, the carrier wave is the voiceband signal, and the modifying wave is the digital data signal. At the receiving end of the transmission path, a similar modem......

in mechanical engineering, a device interposed between a source of power and a specific application for the purpose of adapting one to the other. Most mechanical transmissions function as rotary speed changers; the ratio of the output speed to the input speed may be constant (as in a gearbox) or variable. On variable-speed transmissions the speeds may be variable in discrete steps (as on an autom...

In the nervous system of animals at all levels of the evolutionary scale, the signals containing information about a particular stimulus are electrical in nature. In the past the nerve fibre and its contents were compared to metal wire, while the membrane was compared to insulation around the wire. This comparison was erroneous for a number of reasons. First, the charge carriers in......

...became IPTO director in 1979, the Department of Defense had multiple incompatible packet-switching networks. Kahn forged the Internet from these disparate systems through the creation of the famous Transmission Control Protocol/Internet Protocol (TCP/IP), a process involving industry, academia, and the armed services. Once again DARPA hired individuals well versed in specific fields and gave......

Power-measuring dynamometers may be transmission dynamometers or absorption dynamometers. The former utilize devices that measure torque, in terms of the elastic twist of the shaft or of a special torquemeter inserted between sections of the shaft. The torque is produced by the useful load that the prime mover, motor, or machine is carrying....

The transmission electron microscope has three essential systems: (1) an electron gun, which produces the electron beam, and the condenser system, which focuses the beam onto the object, (2) the image-producing system, consisting of the objective lens, movable specimen stage, and intermediate and projector lenses, which focus the electrons passing through the specimen to form a real, highly......

Atmospheric conditions have a marked effect on the luminous range of lights. They are defined in terms of a transmission factor, which is expressed as a percentage up to a maximum of 100 percent (representing a perfectly clear atmosphere, never attained in practice). Clear weather in the British Isles corresponds to about 80 percent transmission, but in tropical regions it can rise to 90......

component of optical devices consisting of a surface ruled with close, equidistant, and parallel lines for the purpose of resolving light into spectra. A grating is said to be a transmission or reflection grating according to whether it is transparent or mirrored—that is, whether it is ruled on glass or on a thin metal film deposited on a glass blank. Reflection gratings are further......

...and is the lowest-cost fuel in many instances. In addition, the search for inherently cleaner and more efficient ways to burn coal in electric utilities has intensified. The world’s highest-voltage transmission line (1,150 kilovolts) transports electricity from Siberia to consumers in the western republics of the former Soviet Union—a distance of more than 3,000 kilometres. In the...

...had maximum data transmission rates, and he derived a formula for calculating these rates in finite bandwidth noiseless channels. Another pioneer was Nyquist’s colleague R.V.L. Hartley, whose paper “Transmission of Information” (1928) established the first mathematical foundations for information theory....

...textual criticism is indispensable for the student of history, literature, or philosophy. Written texts supply the main foundation for these disciplines, and some knowledge of the processes of their transmission is necessary for understanding and control of the scholar’s basic materials. For the advanced student the criticism and editing of texts offers an unrivalled philological trainin...

...although it is neither the only model of the communication process extant nor is it universally accepted. As originally conceived, the model contained five elements—an information source, a transmitter, a channel of transmission, a receiver, and a destination—all arranged in linear order. Messages (electronic messages, initially) were supposed to travel along this path, to be......

any of a group of chemical agents released by neurons (nerve cells) to stimulate neighbouring neurons, thus allowing impulses to be passed from one cell to the next throughout the nervous system....

...many types of antennas have been developed for different purposes. An antenna may be designed specifically to transmit or to receive, although these functions may be performed by the same antenna. A transmitting antenna, in general, must be able to handle much more electrical energy than a receiving antenna. An antenna also may be designed to transmit at specific frequencies. In the United......

conversion of one chemical element into another. A transmutation entails a change in the structure of atomic nuclei and hence may be induced by a nuclear reaction, such as neutron capture, or occur spontaneously by radioactive decay, such as alpha decay and beta decay. Transmutation of base metals (such as mercury, tin, copper, lead) into p...

any corporation that is registered and operates in more than one country at a time. Generally the corporation has its headquarters in one country and operates wholly or partially owned subsidiaries in other countries. Its subsidiaries report to the corporation’s central headquarters....

Another group stems from the rise of a transnational workforce. Indian-born anthropologist Arjun Appadurai has studied English-speaking professionals who trace their origins to South Asia but who live and work elsewhere. They circulate in a social world that has multiple home bases, and they have gained access to a unique network of individuals and opportunities. For example, many software......

assembly of conductors enclosed by an insulating sheath and laid on the ocean floor for the transmission of messages. Undersea cables for transmitting telegraph signals antedated the invention of the telephone; the first undersea telegraph cable was laid in 1850 between England and France. The Atlantic was spanned in 1858 between Ireland and Newfoundland, but ...

...for Manila using the Martin M-130 (the China Clipper), with a wingspan of 130 feet (equal to the Boeing 727 of a generation later). Passengers were added to the service in 1936, when the first long transoceanic flight began....

...across the Drakensberg, where, except for a short period, the British government was reluctant to pursue them. In 1852 and 1854 the British granted independence to the trekkers in the Transvaal and Transorangia regions, respectively. In Transvaal several warring little polities were established, and factional strife ended only in the 1860s. In Transorangia the trekkers established the Orange......

...involved severing the nerve pathways in the two frontal lobes of the brain, after entry to the brain had been achieved by boring two holes in the skull. This method was soon replaced by the transorbital lobotomy, in which a picklike instrument was forced through the back of the eye sockets to pierce the thin bone that separates the eye sockets from the frontal lobes; the pick’s point......

(“That Which Lies Beyond the River”), historical region of Turkistan in Central Asia east of the Amu Darya (Oxus River) and west of the Syr Darya (Jaxartes River), roughly corresponding to present-day Uzbekistan and parts of Turkmenistan and Kazakhstan. A great centre of Muslim civilization during the European Middle Ages, Transoxania was the centre of the Timurid empire in the 15th...

(“That Which Lies Beyond the River”), historical region of Turkistan in Central Asia east of the Amu Darya (Oxus River) and west of the Syr Darya (Jaxartes River), roughly corresponding to present-day Uzbekistan and parts of Turkmenistan and Kazakhstan. A great centre of Muslim civilization during the European Middle Ages, Transoxania was the centre of the Timurid empire in the 15th...

one of the world’s oldest major ocean races for sailing yachts, a 2,225-mile (3,580-kilometre) event run from various California harbours to Honolulu, Hawaii. It was first held in 1906 and made a biennial event in 1939 to alternate with the Bermuda Race. Since 1941 the race has been from San Pedro, Calif. (Los Angeles’ harbour), to Diamond Head Buoy, off Honolulu. Since the course is...

...blocked all unfiltered light) coated with a thin film of panchromatic (i.e., sensitive to all colours) emulsion, and it resulted in a positive colour transparency. Because Autochrome was a colour transparency and could be viewed only by reflected light, however, researchers continued to look for improvements and alternative colour processes....

Transparency refers to the preference in East Asian music for chamber-music sound ideals; no matter how large an ensemble may be, the individual instruments are meant to be heard. This differs from the orchestral sound ideal, popular in 19th-century Western music, in which the intention is to merge the sounds of the individual instruments into one musical colour. A transparent texture is a......

Because electrons in glass molecules are confined to particular energy levels, they cannot absorb and reemit photons (the basic units of light energy) by skipping from one energy band to another and back again. As a consequence, light energy travels through glass instead of being absorbed and reflected, so that glass is transparent. Furthermore, the molecular units in glass are so small in......

...Jr., and Leopold Mannes, two American musicians working with the Kodak Research Laboratories, initiated the modern era of colour photography with their invention of Kodachrome film. With this reversal (slide) film, colour transparencies could be obtained that were suitable both for projection and for reproduction. A year later the Agfa Company of Germany developed the Agfacolor......

The “Transparente” (completed 1732), designed by Narciso Tomé for the cathedral in Toledo, is among the masterpieces of Churrigueresque. Tomé created an arrangement in which the Holy Sacrament could be placed within a transparent vessel that was visible from both the high altar and the ambulatory, seen both by the congregation and the pilgrim. Sculpted clouds, gilded......

About 1925 Lipchitz began to produce a series of sculptures collectively known as “transparents.” In these curvilinear bronzes, he incorporated open space into the design, depicting mass by integrating solid with void. Many of the transparents, such as Harpist (1928), were cast from small, fragile cardboard-and-wax constructions. Lipchitz translated......

Baja California Sur is sparsely populated and has many isolated areas. Greater attention came to the state following the completion in 1973 of the Transpeninsular Highway, which connects Tijuana at the U.S.-Mexico border with Cabo San Lucas at the peninsula’s southern tip. Ferry services also link the peninsula to the Mexican mainland. There are more than 20 ports, the most important of whi...

in botany, a plant’s loss of water, mainly through the stomates of leaves. Stomates consist of two guard cells that form a small pore on the surfaces of leaves. The guard cells control the opening and closing of the stomates in response to various environmental stimuli. Darkness, internal water deficit, and extremes of temperature tend to close stomates and decrease transpiration; illuminat...

in botany, a generally accepted explanation of the rise of sap in plants by means of intermolecular attractions. Calculation and experiment indicate that the forces of cohesion between water molecules and the forces of adhesion between water molecules and the walls of the vessel cells are sufficient to confer on thin columns of water a tensile strength of at least 30 atmosphere...

...any tree without breaking the column. The cohesion of water explains only maintenance of the sap column; the explanation for the upward movement of the water is accounted for by a mechanism, called transpiration pull, that involves the evaporation of water from leaves. Thus, the explanation for the upward movement of sap in trees is also called the transpiration–cohesion hypothesis. It.....

Suppose that two containers of the same gas but at different temperatures are connected by a tiny hole and that the gas is brought to a steady state. If the hole is small enough and the gas density is low enough that only effusion occurs, the equilibrium pressure will be greater on the high-temperature side. But, if the initial pressures on both sides are equal, gas will flow from the......

in medicine, a section of tissue or a complete organ that is removed from its original natural site and transferred to a new position in the same person or in a separate individual. The term, like the synonym graft, was borrowed by surgeons from horticulture. Both words imply that success will result in a healthy and flourishing graft or transplant, which will gain its nourishment from its new env...

in horticulture, plant or tree removed from one location and reset in the ground at another. Most small deciduous trees may be moved with no soil attached to their roots. Trees of more than 7.5 cm (3 inches) in trunk diameter, however, are best moved balled and burlapped, that is, with a ball of earth enclosing the roots held in place with burlap....

The factors that provoke graft rejection are called transplantation, or histocompatibility, antigens. If donor and recipient have the same antigens, as do identical twins, there can be no rejection. All cells in the body have transplantation antigens except the red blood cells, which carry their own system of blood-group (ABO) antigens. The main human transplantation antigens—called the......