Science & Philosophy: Thallophyta to Toxicology

Science Encyclopedia

Thermocouple

Accurately measuring temperatures over a wide range is a challenge to engineers, physicists, and other scientists. Many techniques have been devised to deal with a wide range of conditions and temperatures. One such technique is a thermocouple. A thermocouple makes use of one aspect of the thermoelectric effect to measure temperatures, the voltage produced between two different wires with junction…

1 minute read

Thermodynamics - Historical Background, Temperature, Expansion Coefficients, Thermostats, Water, Heat, The First Law Of Thermodynamics - Conservation of energy

Thermodynamics is the science that deals with work and heat, and the transformation of one into the other. It is a macroscopic theory, dealing with matter in bulk, disregarding the molecular nature of materials. The corresponding microscopic theory, based on the fact that materials are made up of a vast number of molecules, is called statistical mechanics. The conservation of energy is well known …

4 minute read

Thermometer

A thermometer is a device that registers the temperature of a substance relative to some agreed upon standard. Thermometers use changes in the physical or electronic properties of the device to detect temperature variations. For example, the most common thermometer consists of some sort of liquid sealed into a narrow tube, or capillary, with a calibrated scale attached. The liquid, typically mercu…

2 minute read

Thermostat

A thermostat is a device for controlling heating and cooling systems. It consists of a circuit controlled by a temperature sensitive device and connected to the environmental system. The most common thermostat, such as the one seen in homes and offices, is based on a bimetallic strip. As its name suggests, a bimetallic strip consists of thin strips of two different metals bonded together. One meta…

1 minute read

Third Cinema - Third Cinema And The Third World, Formal Dimensions, Periodizing Third Cinema, Ideology: Racism And Identification

"The anti-imperialist struggle of the peoples of the Third World and of their equivalents inside the imperialist countries constitutes today the axis of the world revolution. Third cinema is, in our opinion, the cinema that recognizes in that struggle the most gigantic cultural, scientific and artistic manifestation of our time, the great possibility of constructing a liberated personality …

1 minute read

Third World - Origins, Theories Of "third World" Development, The Future Of The Third World, Bibliography

The term Third World has long served to describe countries of Africa, Asia, and Latin America that have been seen to share relatively low per-capita incomes, high rates of illiteracy, limited development of industry, agriculture-based economies, short life expectancies, low degrees of social mobility, and unstable political structures. The 120 countries of the Third World also share a history of u…

1 minute read

Third World Literature

As a term of standard usage, though still minus "literature," Third World dates from the 1950s. (The Oxford English Dictionary's first listing for it—still in its French form of Tiers Monde—is dated 1956.) Supposedly coined by the French sociologist Alfred Sauvy (1898–1990) in 1952, it initially referred to the independent and soon-to-be-independent nation…

7 minute read

Thistle

Thistle is the common name given to some plants in several genera of the Cynareae tribe, family Asteraceae. These genera include Cirsium, Carduus, Echinops, Onopordum, Silybum, Centaurea, and Cnicus. The name thistle most often refers to the weedy, prickly plants belonging to the genera Cirsium and Carduus. Thistles are composite flowers, which means their flower is actually a group of small flowe…

1 minute read

Thoracic Surgery

Thoracic surgery refers to surgery performed in the thorax or chest. The anatomy and physiology of the thorax require special procedures to be carried out for the surgery to be done. The thorax is the bony cage consisting of the ribs, the spine, and the breastbone or sternum. The floor of the thorax is formed by the diaphragm. Within the thorax lie the two lungs and the heart, the organs whose fun…

5 minute read

Thrips

Thrips are minute (less than 0.20 in or 5 mm) slender-bodied insects of the order Thysanoptera, characterized by two pairs of veinless, bristle-fringed wings, which are narrow and held over the back when at rest. Although thrips have wings, they do not fly. There are 4,500 species of thrips worldwide. In North America, there are 694 species of thrips in a number of families in two suborders, the T…

2 minute read

Thrombosis

Thrombosis is the formation of a blood clot, or thrombus, in a blood vessel. The process is an exaggeration of a normal and useful event by which the body prevents the loss of blood from veins and arteries as a result of an injury. During thrombosis, the blood clotting process goes beyond the construction of a blockage for a damaged blood vessel and actually produces a solid clump (the clot) that …

2 minute read

Thunderstorm - Thunderstorm Development, Hail, Lightning, And Tornadoes

A thunderstorm is a strong disturbance in the atmosphere bringing heavy rain, lightning, and thunder to areas from one to hundreds of kilometers across. Thunderstorms are formed when humid air near the surface begins rising and cooling. The rising air forms clouds. Lightning over Tamworth, New South Wales, Australia. Photograph by Gordon Garrado. Science Photo Library, National Audubon Societ…

less than 1 minute read

Time - China - Gua Time, Manipulable Time And Social Time: Progress, Alchemy, Salvation, Metaphysical Time: Terms And Philosophies

Chinese thinkers did not devise philosophies, pedagogies, or keys of the sort developed in the West concerning time, and the context was chiefly driven by the state's need for cosmological and ritual correctness, and in some cases by cosmological and apocalyptic notions conveyed in Buddhist and Daoist scriptures. Yet China also produced its own sophisticated metaphysics of time—more …

2 minute read

Time - India - Bibliography

In general, the conceptualization of time in Indian religious and philosophical thought is framed by a dichotomy between the phenomenal world and absolute transcendence—that is, the realms of time and the timeless. The former, the sphere of contingent temporality, is usually understood to be the world of suffering, of change and impermanence, of what is known in Sanskrit as samsara. The lat…

8 minute read

Time - Traditional and Utilitarian - The Origins Of Utilitarian Modernity, Modern Societies, Conclusion, Bibliography

A primary distinction separates sequential (or utilitarian) time, which has to do with the relations of before and after, from traditional time, which has to do with the relation of the present to both the past and the future. For Émile Durkheim (1858–1917), traditional societies were based on solidarities in traditional time, and they relegated to the margins of social life practical …

1 minute read

Tinamous - Species of tinamous

Tinamous are about 45-50 species of ground-dwelling birds that comprise the family Tinamidae, the only member of the order Tinamiformes. Tinamous have a plump, partridge-like body, but they are not related to the "true" partridges, which are species in the pheasant family (Phasianidae). The evolutionary relationships of tinamous are not well understood, but their closest living relat…

4 minute read

Tissue

A tissue is a collection of similar cells grouped to perform a common function. Different tissues are made of their own specialized cells that are adapted for a given function. All animal cells are basically similar. Each cell has a cell wall or plasma membrane that surrounds the cell and contains various receptors that interact with the outside area. A nucleus, Golgi apparatus, mitochondria, and …

1 minute read

Tit Family

The tit family, Paridae, consists of 46 species of small birds, variously known as tits, titmice, and chickadees. These are all song birds, in the order Passeriformes. All are rather small birds, ranging in body length from about 4–8 in (11–20 cm), and mostly occurring in forests, shrubby woodlands, and in urban and suburban habitats. This family of birds is widespread, and its repre…

2 minute read

Toadfish

Toadfish are a poorly known group of marine fishes, the vast majority of which live close to the shoreline but remain close to the sea bed. Unlike most fish, these animals are extremely vocal, with some authorities even reporting that their loud calls can be heard out of water. One North American genus, Porichthys, is more commonly known as the singing midshipman. The calls are produced by muscula…

1 minute read

Toleration - Conceptual Nuances, Related Concepts, Valence, Toleration In The Ancient World, The Rise Of Christian Persecution

Toleration is a policy or attitude toward something that is not approved and yet is not actively rejected. The word comes from the Latin tolerare (to bear or endure), suggesting a root meaning of putting up with something. There is no single and widely accepted definition of the term, and it is hardly an exaggeration to say that every author uses it in his or her own way. Therefore it may be best …

1 minute read

Tomato Family

The tomato, or nightshade family (Solanaceae), contains about 85 genera and 2,300 species. Most of the species are tropical or subtropical in distribution, and a Tomatoes in the field. Photograph by Robert J. Huffman. Field Mark Publications. Reproduced by permission. few are of great economic importance. The region of greatest species richness is Central and South America, but representativ…

2 minute read

Tongue Worms

Tongue worms are bloodsucking endoparasites with a flattened, tongue-like body, and are in the phylum Linguatulida. The final host of these parasites is a predaceous vertebrate, usually a reptile, but sometimes a mammal or a bird. The intermediate host (in which the parasite lives as a larva) can be any of a number of animals, including insects, fish, amphibians, reptiles, and mammals. The 70 spec…

1 minute read

Tonsillitis

Tonsillitis is an inflammation or infection of the tonsils, caused by either bacteria or viruses. The tonsils usually become swollen and very painful, making swallowing difficult. Sometimes the tonsils have spots of exudates (usually leukocytes) or pus on the surface. The surface of the tonsils is covered by recesses or crypts (cryptae tonsillares) that may branch and extend deep into the tonsil. …

1 minute read

Tornado - Tornado Formation, Tornado Characteristics, Tornado History, Prediction And Tracking Of Tornadoes

A tornado is a rapidly spinning column of air formed in severe thunderstorms. The rotating column, or vortex, forms inside the storm cloud then grows downward until it touches the ground. Although a tornado is not as large as its parent thunderstorm, it is capable of extreme damage because it packs very high wind speeds into a compact area. Tornadoes have been known to shatter buildings, drive str…

less than 1 minute read

Torque

According to Isaac Newton, an object at rest will remain at rest, and an object will remain in motion unless acted upon by an outside force. A force, therefore, is what causes any object to move. Any force which causes an object to rotate, turn, or twist is called a torque. Torque is equal to the amount of force being exerted on the object times the object's rotation point to the location w…

1 minute read

Torus

A torus is a doughnut-shaped, three-dimensional figure formed when a circle is rotated through 360° about a line in its plane, but not passing through the circle itself. Imagine, for example, that the circle lies in space such that its diameter is parallel to a straight line. The figure that is formed is a hollow, circular tube, a torus. A torus is sometimes referred to as an anchor ring. …

1 minute read

Total Solar Irradiance - Global warming, Measuring solar irradiance

Total solar irradiance is defined as the amount of radiant energy emitted by the Sun over all wavelengths that fall each second on 11 sq ft (1 sq m) outside the earth's atmosphere. By way of further definition, irradiance is defined as the amount of electromagnetic energy incident on a surface per unit time per unit area. Solar refers to electromagnetic radiation in the spectral range of ap…

11 minute read

Totalitarianism - Origins, Trajectory, Causation, Totalitarian Characteristics, The Coherence Of Totalitarianism, Criticisms And Responses

Totalitarianism is a concept rooted in the horror of modern war, revolution, terror, genocide, and, since 1945, the threat of nuclear annihilation. It is also among the most versatile and contested terms in the political lexicon. At its simplest, the idea suggests that despite Fascist/Nazi "particularism" (the centrality of the nation or the master race) and Bolshevist "univer…

6 minute read

Toucans - Species of toucans

Toucans are 42 species of familiar, brilliantly colored arboreal birds that make up the family Ramphastidae. Toucans are in the order Piciformes, which also includes the woodpeckers. Toucans range from southern Mexico to northern Argentina and Paraguay. Their usual habitat is tropical and subtropical forests and woodlands, and sometimes more open savanna with clumps of trees. Most species occur in…

3 minute read

Touch - How We Feel The Outside World, Touch And Health

Touch is one of the five senses (the others being smell, taste, vision, and hearing) through which animals and people interpret the world around them. While the other senses are localized primarily in a single area (such as vision in the eyes or taste in the tongue), the sensation of touch (or contact with the outside world) can be experienced anywhere on the body, from the top of the head to the …

less than 1 minute read