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235899 | https://en.wikipedia.org/wiki/Circuit%20breaker | Circuit breaker | A circuit breaker is an electrical safety device designed to protect an electrical circuit from damage caused by current in excess of that which the equipment can safely carry (overcurrent). Its basic function is to interrupt current flow to protect equipment and to prevent fire. Unlike a fuse, which operates once and ... | Technology | Components | null |
235926 | https://en.wikipedia.org/wiki/DNA%20polymerase | DNA polymerase | A DNA polymerase is a member of a family of enzymes that catalyze the synthesis of DNA molecules from nucleoside triphosphates, the molecular precursors of DNA. These enzymes are essential for DNA replication and usually work in groups to create two identical DNA duplexes from a single original DNA duplex. During this ... | Biology and health sciences | Molecular biology | Biology |
235968 | https://en.wikipedia.org/wiki/Hydrogenation | Hydrogenation | Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organic compounds. Hydrogenation typically constitutes the addition of pairs of hydrog... | Physical sciences | Organic reactions | Chemistry |
235980 | https://en.wikipedia.org/wiki/Sarcopterygii | Sarcopterygii | Sarcopterygii (; ) — sometimes considered synonymous with Crossopterygii () — is a clade (traditionally a class or subclass) of vertebrate animals which includes a group of bony fish commonly referred to as lobe-finned fish. These vertebrates are characterised by prominent muscular limb buds (lobes) within their fins, ... | Biology and health sciences | Fishes | null |
235988 | https://en.wikipedia.org/wiki/Bichir | Bichir | Bichirs and the reedfish comprise Polypteridae , a family of archaic ray-finned fishes and the only family in the order Polypteriformes .
All the species occur in freshwater habitats in tropical Africa and the Nile River system, mainly swampy, shallow floodplains and estuaries.
Cladistia, polypterids and their fossi... | Biology and health sciences | Chondrosteans | null |
236020 | https://en.wikipedia.org/wiki/Elliptic%20geometry | Elliptic geometry | Elliptic geometry is an example of a geometry in which Euclid's parallel postulate does not hold. Instead, as in spherical geometry, there are no parallel lines since any two lines must intersect. However, unlike in spherical geometry, two lines are usually assumed to intersect at a single point (rather than two). Beca... | Mathematics | Non-Euclidean geometry | null |
236445 | https://en.wikipedia.org/wiki/Nucleophilic%20substitution | Nucleophilic substitution | In chemistry, a nucleophilic substitution (SN) is a class of chemical reactions in which an electron-rich chemical species (known as a nucleophile) replaces a functional group within another electron-deficient molecule (known as the electrophile). The molecule that contains the electrophile and the leaving functional g... | Physical sciences | Organic reactions | Chemistry |
236449 | https://en.wikipedia.org/wiki/Sleep%20paralysis | Sleep paralysis | Sleep paralysis is a state, during waking up or falling asleep, in which a person is conscious but in a complete state of full-body paralysis. During an episode, the person may hallucinate (hear, feel, or see things that are not there), which often results in fear. Episodes generally last no more than a few minutes. It... | Biology and health sciences | Mental disorders | Health |
236466 | https://en.wikipedia.org/wiki/Airborne%20early%20warning%20and%20control | Airborne early warning and control | An airborne early warning and control (AEW&C) system is an airborne radar early warning system designed to detect aircraft, ships, vehicles, missiles and other incoming projectiles at long ranges, as well as performing command and control of the battlespace in aerial engagements by informing and directing friendly figh... | Technology | Military aviation | null |
236666 | https://en.wikipedia.org/wiki/Androgen | Androgen | An androgen (from Greek andr-, the stem of the word meaning ) is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This includes the embryological development of the primary male sex organs, and the developmen... | Biology and health sciences | Animal hormones | Biology |
236674 | https://en.wikipedia.org/wiki/Ayurveda | Ayurveda | Ayurveda (; ) is an alternative medicine system with historical roots in the Indian subcontinent. It is heavily practiced throughout India and Nepal, where as much as 80% of the population report using ayurveda. The theory and practice of ayurveda is pseudoscientific and toxic metals such as lead are used as ingredient... | Biology and health sciences | Alternative and traditional medicine | null |
236856 | https://en.wikipedia.org/wiki/Deinonychus | Deinonychus | Deinonychus ( ; ) is a genus of dromaeosaurid theropod dinosaur with one described species, Deinonychus antirrhopus. This species, which could grow up to long, lived during the early Cretaceous Period, about 115–108 million years ago (from the mid-Aptian to early Albian stages). Fossils have been recovered from the U.... | Biology and health sciences | Theropods | Animals |
236936 | https://en.wikipedia.org/wiki/Rufous%20hummingbird | Rufous hummingbird | The rufous hummingbird (Selasphorus rufus) is a small hummingbird, about long with a long, straight and slender bill. These birds are known for their extraordinary flight skills, flying during their migratory transits. It is one of nine species in the genus Selasphorus.
Taxonomy
The rufous hummingbird was formally d... | Biology and health sciences | Apodiformes | Animals |
236952 | https://en.wikipedia.org/wiki/Wallaroo | Wallaroo | Wallaroo is a common name for several species of moderately large macropods, intermediate in size between the kangaroos and the wallabies. The word "wallaroo" is from the Dharug walaru with spelling influenced by the words "kangaroo" and "wallaby".
Description
Wallaroos are typically distinct species from kangaroos ... | Biology and health sciences | Diprotodontia | Animals |
236981 | https://en.wikipedia.org/wiki/Amniote | Amniote | Amniotes are tetrapod vertebrate animals belonging to the clade Amniota, a large group that comprises the vast majority of living terrestrial and semiaquatic vertebrates. Amniotes evolved from amphibious stem tetrapod ancestors during the Carboniferous period. Those of Amniota are defined as the smallest crown clade co... | Biology and health sciences | General classifications_2 | Animals |
237037 | https://en.wikipedia.org/wiki/Cartesian%20closed%20category | Cartesian closed category | In category theory, a category is Cartesian closed if, roughly speaking, any morphism defined on a product of two objects can be naturally identified with a morphism defined on one of the factors. These categories are particularly important in mathematical logic and the theory of programming, in that their internal lan... | Mathematics | Category theory | null |
237052 | https://en.wikipedia.org/wiki/Entoprocta | Entoprocta | Entoprocta (), or Kamptozoa , is a phylum of mostly sessile aquatic animals, ranging from long. Mature individuals are goblet-shaped, on relatively long stalks. They have a "crown" of solid tentacles whose cilia generate water currents that draw food particles towards the mouth, and both the mouth and anus lie inside... | Biology and health sciences | Spiralia | Animals |
237199 | https://en.wikipedia.org/wiki/Forklift | Forklift | A forklift (also called industrial truck, lift truck, jitney, hi-lo, fork truck, fork hoist, and forklift truck) is a powered industrial truck used to lift and move materials over short distances. The forklift was developed in the early 20th century by various companies, including Clark, which made transmissions, and Y... | Technology | Industrial machinery | null |
237248 | https://en.wikipedia.org/wiki/Medical%20ethics | Medical ethics | Medical ethics is an applied branch of ethics which analyzes the practice of clinical medicine and related scientific research. Medical ethics is based on a set of values that professionals can refer to in the case of any confusion or conflict. These values include the respect for autonomy, non-maleficence, beneficence... | Biology and health sciences | General concepts | null |
19349161 | https://en.wikipedia.org/wiki/Cambrian%20explosion | Cambrian explosion | The Cambrian explosion (also known as Cambrian radiation or Cambrian diversification) is an interval of time beginning approximately in the Cambrian period of the early Paleozoic, when a sudden radiation of complex life occurred and practically all major animal phyla started appearing in the fossil record. It lasted f... | Physical sciences | Geological history | null |
20536726 | https://en.wikipedia.org/wiki/Ocean%20dynamics | Ocean dynamics | Ocean dynamics define and describe the flow of water within the oceans. Ocean temperature and motion fields can be separated into three distinct layers: mixed (surface) layer, upper ocean (above the thermocline), and deep ocean.
Ocean dynamics has traditionally been investigated by sampling from instruments in situ.
... | Physical sciences | Oceanography | Earth science |
12618815 | https://en.wikipedia.org/wiki/Minneapolis%20Skyway%20System | Minneapolis Skyway System | The Minneapolis Skyway System is an interlinked collection of enclosed pedestrian footbridges that connect various buildings in 80 full city blocks over of Downtown Minneapolis, enabling people to walk in climate-controlled comfort year-round. The skyways are owned by individual buildings in Minneapolis, and as such t... | Technology | Bridges | null |
734845 | https://en.wikipedia.org/wiki/Shanghai%20Metro | Shanghai Metro | The Shanghai Metro (; Shanghainese: Zaon6he5 Di6thiq7) is a rapid transit system in Shanghai, operating urban and suburban transit services to 14 of its 16 municipal districts and to the neighboring township of Huaqiao, in Kunshan, Jiangsu Province.
Forming the vast majority of the broader, multi-operator Shanghai rai... | Technology | China | null |
735512 | https://en.wikipedia.org/wiki/K%E2%80%93Ar%20dating | K–Ar dating | Potassium–argon dating, abbreviated K–Ar dating, is a radiometric dating method used in geochronology and archaeology. It is based on measurement of the product of the radioactive decay of an isotope of potassium (K) into argon (Ar). Potassium is a common element found in many materials, such as feldspars, micas, clay ... | Physical sciences | Geochronology | Earth science |
735672 | https://en.wikipedia.org/wiki/Cellular%20network | Cellular network | A cellular network or mobile network is a telecommunications network where the link to and from end nodes is wireless and the network is distributed over land areas called cells, each served by at least one fixed-location transceiver (such as a base station). These base stations provide the cell with the network covera... | Technology | Networks | null |
735965 | https://en.wikipedia.org/wiki/Valence%20bond%20theory | Valence bond theory | In chemistry, valence bond (VB) theory is one of the two basic theories, along with molecular orbital (MO) theory, that were developed to use the methods of quantum mechanics to explain chemical bonding. It focuses on how the atomic orbitals of the dissociated atoms combine to give individual chemical bonds when a mole... | Physical sciences | Chemical bonds | null |
736449 | https://en.wikipedia.org/wiki/Macram%C3%A9 | Macramé | Macramé is a form of textile produced using knotting (rather than weaving or knitting) techniques.
The primary knots of macramé are the square (or reef knot) and forms of "hitching": various combinations of half hitches. It was long crafted by sailors, especially in elaborate or ornamental knotting forms, to cover any... | Technology | Other techniques | null |
736919 | https://en.wikipedia.org/wiki/Camino%20de%20Santiago | Camino de Santiago | The Camino de Santiago (, ; ), or in English the Way of St. James, is a network of pilgrims' ways or pilgrimages leading to the shrine of the apostle James in the cathedral of Santiago de Compostela in Galicia in northwestern Spain, where tradition holds that the remains of the apostle are buried.
As Pope Benedict XVI... | Technology | Ground transportation networks | null |
737029 | https://en.wikipedia.org/wiki/Cloudburst | Cloudburst | A cloudburst is an enormous amount of precipitation in a short period of time, sometimes accompanied by hail and thunder, which is capable of creating flood conditions. Cloudbursts can quickly dump large amounts of water, e.g. 25 mm of the precipitation corresponds to 25,000 metric tons per square kilometre (1 inch cor... | Physical sciences | Precipitation | Earth science |
737584 | https://en.wikipedia.org/wiki/Toyota%20Corolla | Toyota Corolla | The is a series of compact cars (formerly subcompact) manufactured and marketed globally by the Japanese automaker Toyota Motor Corporation. Introduced in 1966, the Corolla was the best-selling car worldwide by 1974 and has been one of the best-selling cars in the world since then. In 1997, the Corolla became the best... | Technology | Specific automobiles | null |
737798 | https://en.wikipedia.org/wiki/Hydroxyl%20radical | Hydroxyl radical | The hydroxyl radical, •HO, is the neutral form of the hydroxide ion (HO–). Hydroxyl radicals are highly reactive and consequently short-lived; however, they form an important part of radical chemistry. Most notably hydroxyl radicals are produced from the decomposition of hydroperoxides (ROOH) or, in atmospheric chemist... | Physical sciences | Hydrogen compounds | Chemistry |
738149 | https://en.wikipedia.org/wiki/K%C3%A1rm%C3%A1n%20line | Kármán line | The Kármán line (or von Kármán line ) is a conventional definition of the edge of space. It is not universally accepted. The international record-keeping body FAI (Fédération aéronautique internationale) defines the Kármán line at an altitude of above mean sea level.
While named after Theodore von Kármán, who calcul... | Physical sciences | Atmosphere: General | Earth science |
738178 | https://en.wikipedia.org/wiki/Orbital%20spaceflight | Orbital spaceflight | An orbital spaceflight (or orbital flight) is a spaceflight in which a spacecraft is placed on a trajectory where it could remain in space for at least one orbit. To do this around the Earth, it must be on a free trajectory which has an altitude at perigee (altitude at closest approach) around ; this is the boundary of... | Technology | Basics_6 | null |
4614583 | https://en.wikipedia.org/wiki/Sea%20toad | Sea toad | The sea toads and coffinfishes are a family, the Chaunacidae, of deep-sea ray-finned fishes belonging to the monotypic suborder Chaunacoidei within the order Lophiiformes, the anglerfishes. These are bottom-dwelling fishes found on the continental slopes of the Atlantic, Indian, and Pacific Oceans, at depths to at leas... | Biology and health sciences | Acanthomorpha | Animals |
4615016 | https://en.wikipedia.org/wiki/Domestic%20canary | Domestic canary | The domestic canary, often simply known as the canary (Serinus canaria forma domestica), is a domesticated form of the wild canary, a small songbird in the finch family originating from the Macaronesian Islands of the Azores, Madeira and the Canary Islands.
Canaries were first bred in captivity in the 17th century, ha... | Biology and health sciences | Passerida | Animals |
7960760 | https://en.wikipedia.org/wiki/Hubble%20volume | Hubble volume | In cosmology, a Hubble volume (named for the astronomer Edwin Hubble) or Hubble sphere, Hubble bubble, subluminal sphere, causal sphere and sphere of causality is a spherical region of the observable universe surrounding an observer beyond which objects recede from that observer at a rate greater than the speed of ligh... | Physical sciences | Physical cosmology | Astronomy |
7962344 | https://en.wikipedia.org/wiki/Rod%20end%20bearing | Rod end bearing | A rod end bearing, also known as a heim joint (N. America) or rose joint (U.K. and elsewhere), is a mechanical articulating joint. Such joints are used on the ends of control rods, steering links, tie rods, or anywhere a precision articulating joint is required, and where a clevis end (which requires perfect 90-degree ... | Technology | Mechanisms | null |
7966125 | https://en.wikipedia.org/wiki/HTML5 | HTML5 | HTML5 (Hypertext Markup Language 5) is a markup language used for structuring and presenting hypertext documents on the World Wide Web. It was the fifth and final major HTML version that is now a retired World Wide Web Consortium (W3C) recommendation. The current specification is known as the HTML Living Standard. It i... | Technology | Markup languages | null |
2493928 | https://en.wikipedia.org/wiki/Weever | Weever | Weevers (or weeverfish) are nine extant species of ray-finned fishes of the family Trachinidae in the order Perciformes, part of the wider clade Percomorpha. They are long (up to 37 cm), mainly brown in color, and have venomous spines on their first dorsal fin and gills. During the day, weevers bury themselves in sand,... | Biology and health sciences | Acanthomorpha | Animals |
2494084 | https://en.wikipedia.org/wiki/Hair%20care | Hair care | Hair care or haircare is an overall term for hygiene and cosmetology involving the hair which grows from the human scalp, and to a lesser extent facial, pubic and other body hair. Hair care routines differ according to an individual's culture and the physical characteristics of one's hair. Hair may be colored, trimmed,... | Biology and health sciences | Hygiene and grooming: General | Health |
2494915 | https://en.wikipedia.org/wiki/Masiakasaurus | Masiakasaurus | Masiakasaurus is a genus of small predatory noasaurid theropod dinosaurs from the Late Cretaceous of Madagascar. In Malagasy, masiaka means "vicious"; thus, the genus name means "vicious lizard". The type species, Masiakasaurus knopfleri, was named after the musician Mark Knopfler, whose music inspired the expedition ... | Biology and health sciences | Theropods | Animals |
18361733 | https://en.wikipedia.org/wiki/Rapid%20transit | Rapid transit | Rapid transit or mass rapid transit (MRT) or heavy rail, commonly referred to as metro, is a type of high-capacity public transport that is generally built in urban areas. A grade separated rapid transit line below ground surface through a tunnel can be regionally called a subway, tube, metro or underground. They are s... | Technology | Trains | null |
18365750 | https://en.wikipedia.org/wiki/White%20currant | White currant | The white currant or whitecurrant is a group of cultivars of the red currant (Ribes rubrum), a species of flowering plant in the family Grossulariaceae, native to Europe.
It is sometimes mislabelled as Ribes glandulosum, called the "skunk currant" in the United States.
Description
It is a deciduous shrub growing to ... | Biology and health sciences | Berries | Plants |
17158563 | https://en.wikipedia.org/wiki/Sheep | Sheep | Sheep (: sheep) or domestic sheep (Ovis aries) are a domesticated, ruminant mammal typically kept as livestock. Although the term sheep can apply to other species in the genus Ovis, in everyday usage it almost always refers to domesticated sheep. Like all ruminants, sheep are members of the order Artiodactyla, the eve... | Biology and health sciences | Biology | null |
1192866 | https://en.wikipedia.org/wiki/Accommodation%20%28vertebrate%20eye%29 | Accommodation (vertebrate eye) | Accommodation is the process by which the vertebrate eye changes optical power to maintain a clear image or focus on an object as its distance varies. In this, distances vary for individuals from the far point—the maximum distance from the eye for which a clear image of an object can be seen, to the near point—the mini... | Biology and health sciences | Visual system | Biology |
1193370 | https://en.wikipedia.org/wiki/Gas%20laser | Gas laser | A gas laser is a laser in which an electric current is discharged through a gas to produce coherent light. The gas laser was the first continuous-light laser and the first laser to operate on the principle of converting electrical energy to a laser light output. The first gas laser, the Helium–neon laser (HeNe), was co... | Technology | Lasers | null |
1194227 | https://en.wikipedia.org/wiki/Black-backed%20jackal | Black-backed jackal | The black-backed jackal (Lupulella mesomelas), also called the silver-backed jackal, is a medium-sized canine native to eastern and southern Africa. These regions are separated by roughly 900 kilometers.
One region includes the southernmost tip of the continent, including South Africa, Namibia, Botswana and Zimbabwe. ... | Biology and health sciences | Canines | Animals |
1194257 | https://en.wikipedia.org/wiki/Gomphothere | Gomphothere | Gomphotheres are an extinct group of proboscideans related to modern elephants. First appearing in Africa during the Oligocene, they dispersed into Eurasia and North America during the Miocene and arrived in South America during the Pleistocene as part of the Great American Interchange. Gomphotheres are a paraphyletic ... | Biology and health sciences | Proboscidea | Animals |
1194393 | https://en.wikipedia.org/wiki/Roadrunner | Roadrunner | The roadrunners (genus Geococcyx), also known as chaparral birds or chaparral cocks, are two species of fast-running ground cuckoos with long tails and crests. They are found in the southwestern and south-central United States, Mexico and Central America, usually in the desert. Although capable of flight, roadrunners g... | Biology and health sciences | Cuculiformes and relatives | Animals |
1195100 | https://en.wikipedia.org/wiki/Giant%20Gippsland%20earthworm | Giant Gippsland earthworm | The giant Gippsland earthworm (Megascolides australis) is one of Australia's 1,000 native earthworm species.
Description
These giant earthworms average long and in diameter and can reach in length; however, their body is able to expand and contract making them appear much larger. On average they weigh about . They ... | Biology and health sciences | Lophotrochozoa | Animals |
1195294 | https://en.wikipedia.org/wiki/Degree%20%28angle%29 | Degree (angle) | A degree (in full, a degree of arc, arc degree, or arcdegree), usually denoted by ° (the degree symbol), is a measurement of a plane angle in which one full rotation is 360 degrees.
It is not an SI unit—the SI unit of angular measure is the radian—but it is mentioned in the SI brochure as an accepted unit. Because a f... | Physical sciences | Angle | null |
1195462 | https://en.wikipedia.org/wiki/Environmental%20studies | Environmental studies | Environmental studies (EVS or EVST) is a multidisciplinary academic field which systematically studies human interaction with the environment. Environmental studies connects principles from the physical sciences, commerce/economics, the humanities, and social sciences to address complex contemporary environmental issue... | Physical sciences | Earth science basics: General | Earth science |
1195577 | https://en.wikipedia.org/wiki/Lacrimal%20gland | Lacrimal gland | The lacrimal glands are paired exocrine glands, one for each eye, found in most terrestrial vertebrates and some marine mammals, that secrete the aqueous layer of the tear film. In humans, they are situated in the upper lateral region of each orbit, in the lacrimal fossa of the orbit formed by the frontal bone. Inflamm... | Biology and health sciences | Exocrine system | Biology |
1195815 | https://en.wikipedia.org/wiki/Homo%20antecessor | Homo antecessor | Homo antecessor (Latin "pioneer man") is an extinct species of archaic human recorded in the Spanish Sierra de Atapuerca, a productive archaeological site, from 1.2 to 0.8 million years ago during the Early Pleistocene. Populations of this species may have been present elsewhere in Western Europe, and were among the fi... | Biology and health sciences | Homo | Biology |
15434651 | https://en.wikipedia.org/wiki/Glutamate%20flavoring | Glutamate flavoring | Glutamate flavoring is the generic name for flavor-enhancing compounds based on glutamic acid and its salts (glutamates). These compounds provide an umami (savory) taste to food.
Glutamic acid and glutamates are natural constituents of many fermented or aged foods, including soy sauce, fermented bean paste, and cheese... | Physical sciences | Glutamates | Chemistry |
6064895 | https://en.wikipedia.org/wiki/Sea%20snail | Sea snail | Sea snails are slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the absence of a visible shell.
Definition
Determining whether some gastropods should be called se... | Biology and health sciences | Gastropods | Animals |
10304194 | https://en.wikipedia.org/wiki/Daytime | Daytime | Daytime or day as observed on Earth is the period of the day during which a given location experiences natural illumination from direct sunlight. Daytime occurs when the Sun appears above the local horizon, that is, anywhere on the globe's hemisphere facing the Sun. In direct sunlight the movement of the sun can be rec... | Physical sciences | Celestial mechanics | Astronomy |
10308785 | https://en.wikipedia.org/wiki/Differentiation%20rules | Differentiation rules | This is a summary of differentiation rules, that is, rules for computing the derivative of a function in calculus.
Elementary rules of differentiation
Unless otherwise stated, all functions are functions of real numbers (R) that return real values; although more generally, the formulae below apply wherever they are ... | Mathematics | Differential calculus | null |
436034 | https://en.wikipedia.org/wiki/Kleptomania | Kleptomania | Kleptomania is the inability to resist the urge to steal items, usually for reasons other than personal use or financial gain. First described in 1816, kleptomania is classified in psychiatry as an impulse control disorder. Some of the main characteristics of the disorder suggest that kleptomania could be an obsessive-... | Biology and health sciences | Mental disorders | Health |
436114 | https://en.wikipedia.org/wiki/Cupressus | Cupressus | Cupressus is one of several genera of evergreen conifers within the family Cupressaceae that have the common name cypress; for the others, see cypress. It is considered a polyphyletic group. Based on genetic and morphological analysis, the genus Cupressus is found in the subfamily Cupressoideae. The common name "cypre... | Biology and health sciences | Gymnosperms | null |
436136 | https://en.wikipedia.org/wiki/Hesperocyparis%20macrocarpa | Hesperocyparis macrocarpa | Hesperocyparis macrocarpa also known as Cupressus macrocarpa, or the Monterey cypress is a coniferous tree, and is one of several species of cypress trees endemic to California.
The Monterey cypress is found naturally only on the Central Coast of California. Due to being a glacial relict, the natural distributional ra... | Biology and health sciences | Cupressaceae | Plants |
436166 | https://en.wikipedia.org/wiki/Variable-frequency%20oscillator | Variable-frequency oscillator | A variable frequency oscillator (VFO) in electronics is an oscillator whose frequency can be tuned (i.e., varied) over some range. It is a necessary component in any tunable radio transmitter and in receivers that work by the superheterodyne principle. The oscillator controls the frequency to which the apparatus is tun... | Technology | Functional circuits | null |
436251 | https://en.wikipedia.org/wiki/Bactrian%20camel | Bactrian camel | The Bactrian camel (Camelus bactrianus), also known as the Mongolian camel, domestic Bactrian camel or two-humped camel, is a large camel native to the steppes of Central Asia. It has two humps on its back, in contrast to the single-humped dromedary. Its population of 2 million exists mainly in the domesticated form. T... | Biology and health sciences | Artiodactyla | null |
436303 | https://en.wikipedia.org/wiki/Cownose%20ray | Cownose ray | The cownose ray (Rhinoptera bonasus) is a species of Batoidea found throughout a large part of the western Atlantic and Caribbean, from New England to southern Brazil (the East Atlantic populations are now generally considered a separate species, the Lusitanian cownose ray (R. marginata)). These rays also belong to the... | Biology and health sciences | Batoidea | Animals |
436418 | https://en.wikipedia.org/wiki/Compressed-air%20energy%20storage | Compressed-air energy storage | Compressed-air-energy storage (CAES) is a way to store energy for later use using compressed air. At a utility scale, energy generated during periods of low demand can be released during peak load periods.
The first utility-scale CAES project was in the Huntorf power plant in Elsfleth, Germany, and is still operationa... | Technology | Energy storage | null |
436600 | https://en.wikipedia.org/wiki/Decapod | Decapod | The Decapoda or decapods () is a large order of crustaceans within the class Malacostraca, and includes crabs, lobsters, crayfish, shrimp, and prawns. Most decapods are scavengers. The order is estimated to contain nearly 15,000 extant species in around 2,700 genera, with around 3,300 fossil species. Nearly half of the... | Biology and health sciences | Crustaceans | null |
436779 | https://en.wikipedia.org/wiki/Boundary%20value%20problem | Boundary value problem | In the study of differential equations, a boundary-value problem is a differential equation subjected to constraints called boundary conditions. A solution to a boundary value problem is a solution to the differential equation which also satisfies the boundary conditions.
Boundary value problems arise in several branc... | Mathematics | Differential equations | null |
436824 | https://en.wikipedia.org/wiki/Gerontology | Gerontology | Gerontology ( ) is the study of the social, cultural, psychological, cognitive, and biological aspects of aging. The word was coined by Ilya Ilyich Mechnikov in 1903, from the Greek (), meaning "old man", and (), meaning "study of". The field is distinguished from geriatrics, which is the branch of medicine that spec... | Biology and health sciences | Health and fitness: General | Health |
436825 | https://en.wikipedia.org/wiki/Geriatrics | Geriatrics | Geriatrics, or geriatric medicine, is a medical specialty focused on providing care for the unique health needs of the elderly. The term geriatrics originates from the Greek γέρων geron meaning "old man", and ιατρός iatros meaning "healer". It aims to promote health by preventing, diagnosing and treating disease in old... | Biology and health sciences | Fields of medicine | null |
436896 | https://en.wikipedia.org/wiki/Tarantula%20hawk | Tarantula hawk | A tarantula hawk is a spider wasp (Pompilidae) that preys on tarantulas. Tarantula hawks belong to any of the many species in the genera Pepsis and Hemipepsis. They are one of the largest parasitoid wasps, using their sting to paralyze their prey before dragging it into a brood nest as living food; a single egg is laid... | Biology and health sciences | Hymenoptera | Animals |
437052 | https://en.wikipedia.org/wiki/Positional%20notation | Positional notation | Positional notation, also known as place-value notation, positional numeral system, or simply place value, usually denotes the extension to any base of the Hindu–Arabic numeral system (or decimal system). More generally, a positional system is a numeral system in which the contribution of a digit to the value of a numb... | Mathematics | Basics | null |
437103 | https://en.wikipedia.org/wiki/Root%20canal | Root canal | A root canal is the naturally occurring anatomic space within the root of a tooth. It consists of the pulp chamber (within the coronal part of the tooth), the main canal(s), and more intricate anatomical branches that may connect the root canals to each other or to the surface of the root.
Structure
At the center of ... | Biology and health sciences | Dentistry | null |
437348 | https://en.wikipedia.org/wiki/Tsuga | Tsuga | Tsuga (, from Japanese (), the name of Tsuga sieboldii) is a genus of conifers in the subfamily Abietoideae of Pinaceae, the pine family. The English-language common name "hemlock" arose from a perceived similarity in the smell of its crushed foliage to that of the unrelated plant hemlock. Unlike the latter, Tsuga spe... | Biology and health sciences | Pinaceae | Plants |
437461 | https://en.wikipedia.org/wiki/Megalania | Megalania | Megalania (Varanus priscus) is an extinct species of giant monitor lizard, part of the megafaunal assemblage that inhabited Australia during the Pleistocene. It is the largest terrestrial lizard known to have existed, but the fragmentary nature of known remains make estimates highly uncertain. Recent studies suggest t... | Biology and health sciences | Prehistoric squamates | Animals |
437573 | https://en.wikipedia.org/wiki/Black-eyed%20pea | Black-eyed pea | The black-eyed pea or black-eyed bean is a legume grown around the world for its medium-sized, edible bean. It is a subspecies of the cowpea, an Old World plant domesticated in Africa, and is sometimes simply called a cowpea.
The common commercial variety is called the California Blackeye; it is pale-colored with a pr... | Biology and health sciences | Pulses | Plants |
437619 | https://en.wikipedia.org/wiki/Shear%20stress | Shear stress | Shear stress (often denoted by , Greek: tau) is the component of stress coplanar with a material cross section. It arises from the shear force, the component of force vector parallel to the material cross section. Normal stress, on the other hand, arises from the force vector component perpendicular to the material cr... | Physical sciences | Solid mechanics | Physics |
437762 | https://en.wikipedia.org/wiki/Fagus%20sylvatica | Fagus sylvatica | Fagus sylvatica, the European beech or common beech, is a large, graceful deciduous tree in the beech family with smooth silvery-gray bark, large leaf area, and a short trunk with low branches.
Description
Fagus sylvatica is a large tree, capable of reaching heights of up to tall and trunk diameter, though more ty... | Biology and health sciences | Fagales | Plants |
437771 | https://en.wikipedia.org/wiki/Cryptomeria | Cryptomeria | Cryptomeria (literally "hidden parts") is a monotypic genus of conifer in the cypress family Cupressaceae. It includes only one species, Cryptomeria japonica (syn. Cupressus japonica L.f.). It is considered to be endemic to Japan, where it is known as . The tree is called Japanese cedar or Japanese redwood in English... | Biology and health sciences | Cupressaceae | Plants |
437856 | https://en.wikipedia.org/wiki/Group%204%20element | Group 4 element | |-
! colspan=2 style="text-align:left;" | ↓ Period
|-
! 4
|
|-
! 5
|
|-
! 6
|
|-
! 7
|
|-
| colspan="2"|
Legendprimordial element
synthetic element
|}
Group 4 is the second group of transition metals in the periodic table. It contains only the four elements titanium (Ti), zirconium (Zr), hafnium (Hf), and rutherf... | Physical sciences | Group 4 | Chemistry |
437861 | https://en.wikipedia.org/wiki/Atomic%20spectroscopy | Atomic spectroscopy | In physics, atomic spectroscopy is the study of the electromagnetic radiation absorbed and emitted by atoms. Since unique elements have unique emission spectra, atomic spectroscopy is applied for determination of elemental compositions. It can be divided by atomization source or by the type of spectroscopy used. In th... | Physical sciences | Spectroscopy | Chemistry |
437919 | https://en.wikipedia.org/wiki/Acer%20pseudoplatanus | Acer pseudoplatanus | Acer pseudoplatanus, known as the sycamore in the British Isles and as the sycamore maple in the United States, is a species of maple native to Central Europe and Western Asia. It is a large deciduous, broad-leaved tree, tolerant of wind and coastal exposure.
Although native to an area ranging from France eastward to ... | Biology and health sciences | Sapindales | Plants |
437931 | https://en.wikipedia.org/wiki/Alnus%20glutinosa | Alnus glutinosa | Alnus glutinosa, the common alder, black alder, European alder, European black alder, or just alder, is a species of tree in the family Betulaceae, native to most of Europe, southwest Asia and northern Africa. It thrives in wet locations where its association with the bacterium Frankia alni enables it to grow in poor q... | Biology and health sciences | Fagales | Plants |
437956 | https://en.wikipedia.org/wiki/Sweet%20chestnut | Sweet chestnut | The sweet chestnut (Castanea sativa), also known as the Spanish chestnut or just chestnut, is a species of tree in the family Fagaceae, native to Southern Europe and Asia Minor, and widely cultivated throughout the temperate world. A substantial, long-lived deciduous tree, it produces an edible seed, the chestnut, whic... | Biology and health sciences | Nuts | Plants |
437961 | https://en.wikipedia.org/wiki/Electric%20ray | Electric ray | The electric rays are a group of rays, flattened cartilaginous fish with enlarged pectoral fins, composing the order Torpediniformes . They are known for being capable of producing an electric discharge, ranging from 8 to 220 volts, depending on species, used to stun prey and for defense. There are 69 species in four f... | Biology and health sciences | Batoidea | null |
438178 | https://en.wikipedia.org/wiki/Ribes | Ribes | Ribes () is a genus of about 200 known species of flowering plants, most of them native to the temperate regions of the Northern Hemisphere. The species may be known as various kinds of currants, such as redcurrants, blackcurrants, and whitecurrants, or as gooseberries, and some are cultivated for their edible fruit or... | Biology and health sciences | Saxifragales | Plants |
438261 | https://en.wikipedia.org/wiki/Ulmus%20glabra | Ulmus glabra | Ulmus glabra, the wych elm or Scots elm, has the widest range of the European elm species, from Ireland eastwards to the Ural Mountains, and from the Arctic Circle south to the mountains of the Peloponnese and Sicily, where the species reaches its southern limit in Europe; it is also found in Iran. A large deciduous tr... | Biology and health sciences | Rosales | Plants |
438266 | https://en.wikipedia.org/wiki/Ulmaceae | Ulmaceae | The Ulmaceae () are a family of flowering plants that includes the elms (genus Ulmus), and the zelkovas (genus Zelkova). Members of the family are widely distributed throughout the north temperate zone, and have a scattered distribution elsewhere except for Australasia.
The family was formerly sometimes treated to inc... | Biology and health sciences | Rosales | Plants |
438476 | https://en.wikipedia.org/wiki/Path%20integral%20formulation | Path integral formulation | The path integral formulation is a description in quantum mechanics that generalizes the stationary action principle of classical mechanics. It replaces the classical notion of a single, unique classical trajectory for a system with a sum, or functional integral, over an infinity of quantum-mechanically possible traje... | Physical sciences | Quantum mechanics | Physics |
438703 | https://en.wikipedia.org/wiki/Dormouse | Dormouse | A dormouse is a rodent of the family Gliridae (this family is also variously called Myoxidae or Muscardinidae by different taxonomists). Dormice are nocturnal animals found in Africa, Asia, and Europe. They are named for their long, dormant hibernation period of six months or longer. There are 9 genera and 28 living sp... | Biology and health sciences | Rodents | null |
438758 | https://en.wikipedia.org/wiki/Mammalogy | Mammalogy | In zoology, mammalogy is the study of mammals – a class of vertebrates with characteristics such as homeothermic metabolism, fur, four-chambered hearts, and complex nervous systems. Mammalogy has also been known as mastology, theriology, and therology. The archive of number of mammals on earth is constantly growing, bu... | Biology and health sciences | Basics_2 | Biology |
438944 | https://en.wikipedia.org/wiki/Actin | Actin | Actin is a family of globular multi-functional proteins that form microfilaments in the cytoskeleton, and the thin filaments in muscle fibrils. It is found in essentially all eukaryotic cells, where it may be present at a concentration of over 100 μM; its mass is roughly 42 kDa, with a diameter of 4 to 7 nm.
An actin ... | Biology and health sciences | Cell parts | Biology |
1803999 | https://en.wikipedia.org/wiki/Dagger-axe | Dagger-axe | The dagger-axe () is a type of polearm that was in use from the Longshan culture until the Han dynasty in China. It consists of a dagger-shaped blade, mounted by its tang to a perpendicular wooden shaft. The earliest dagger-axe blades were made of stone. Later versions used bronze. Jade versions were also made for cere... | Technology | Polearms | null |
1804896 | https://en.wikipedia.org/wiki/Prunus%20serotina | Prunus serotina | Prunus serotina, commonly called black cherry, wild black cherry, rum cherry, or mountain black cherry, is a deciduous tree or shrub in the rose family Rosaceae. Despite its common names, it is not very closely related to commonly cultivated cherries. It is found in the Americas.
Description
Prunus serotina is a mediu... | Biology and health sciences | Stone fruits | Plants |
1804940 | https://en.wikipedia.org/wiki/Furry%20lobster | Furry lobster | Furry lobsters (sometimes called coral lobsters) are small decapod crustaceans, closely related to the slipper lobsters and spiny lobsters. The antennae are not as enlarged as in spiny and slipper lobsters, and the body is covered in short hairs, hence the name furry lobster. Although previously considered a family in ... | Biology and health sciences | Crayfishes and lobsters | Animals |
1805751 | https://en.wikipedia.org/wiki/Vicinal%20%28chemistry%29 | Vicinal (chemistry) | In chemistry the descriptor vicinal (from Latin vicinus = neighbor), abbreviated vic, is a descriptor that identifies two functional groups as bonded to two adjacent carbon atoms (i.e., in a 1,2-relationship). It may arise from vicinal difunctionalization.
Relation of atoms in a molecule
For example, the molecule 2,3... | Physical sciences | Concepts_2 | Chemistry |
20541773 | https://en.wikipedia.org/wiki/Wind%20turbine | Wind turbine | A wind turbine is a device that converts the kinetic energy of wind into electrical energy. , hundreds of thousands of large turbines, in installations known as wind farms, were generating over 650 gigawatts of power, with 60 GW added each year. Wind turbines are an increasingly important source of intermittent renewab... | Technology | Electricity generation and distribution | null |
20548535 | https://en.wikipedia.org/wiki/Nameplate%20capacity | Nameplate capacity | Nameplate capacity, also known as the rated capacity, nominal capacity, installed capacity, maximum effect or gross capacity, is the intended full-load sustained output of a facility such as a power station, electric generator, a chemical plant, fuel plant, mine, metal refinery, and many others. Nameplate capacity i... | Technology | Concepts | null |
19363373 | https://en.wikipedia.org/wiki/Moons%20of%20Haumea | Moons of Haumea | The dwarf planet Haumea has two known moons, Hiʻiaka and Namaka, named after Hawaiian goddesses. These small moons were discovered in 2005, from observations of Haumea made at the large telescopes of the W. M. Keck Observatory in Hawaii.
Haumea's moons are unusual in a number of ways. They are thought to be part of it... | Physical sciences | Solar System | Astronomy |
3428791 | https://en.wikipedia.org/wiki/Blue%20hour | Blue hour | The blue hour (from French ; ) is the period of twilight (in the morning or evening, around the nautical stage) when the Sun is at a significant depth below the horizon. During this time, the remaining sunlight takes on a mostly blue shade. This shade differs from the colour of the sky on a clear day, which is caused b... | Physical sciences | Celestial mechanics | Astronomy |
3430618 | https://en.wikipedia.org/wiki/Temnodontosaurus | Temnodontosaurus | Temnodontosaurus (meaning "cutting-tooth lizard") is an extinct genus of large ichthyosaurs that lived during the Lower Jurassic in what is now Europe and possibly Chile. The first known fossil is a specimen consisting of a complete skull and partial skeleton discovered on a cliff by Joseph and Mary Anning around the e... | Biology and health sciences | Prehistoric marine reptiles | Animals |
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