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505484 | https://en.wikipedia.org/wiki/Spermatogenesis | Spermatogenesis | Spermatogenesis is the process by which haploid spermatozoa develop from germ cells in the seminiferous tubules of the testicle. This process starts with the mitotic division of the stem cells located close to the basement membrane of the tubules. These cells are called spermatogonial stem cells. The mitotic division ... | Biology and health sciences | Animal reproduction | Biology |
505536 | https://en.wikipedia.org/wiki/Blood%20donation | Blood donation | A blood donation occurs when a person voluntarily has blood drawn and used for transfusions and/or made into biopharmaceutical medications by a process called fractionation (separation of whole blood components). A donation may be of whole blood, or of specific components directly (apheresis). Blood banks often partici... | Biology and health sciences | Medical procedures: General | Health |
505721 | https://en.wikipedia.org/wiki/Wolfdog | Wolfdog | A wolfdog is a canine produced by the mating of a domestic dog (Canis familiaris) with a gray wolf (Canis lupus), eastern wolf (Canis lycaon), red wolf (Canis rufus), or Ethiopian wolf (Canis simensis) to produce a hybrid.
Admixture
There are a range of experts who believe that they can tell the difference between a ... | Biology and health sciences | Canines | Animals |
506239 | https://en.wikipedia.org/wiki/Woolly%20rhinoceros | Woolly rhinoceros | The woolly rhinoceros (Coelodonta antiquitatis) is an extinct species of rhinoceros that inhabited northern Eurasia during the Pleistocene epoch. The woolly rhinoceros was a member of the Pleistocene megafauna. The woolly rhinoceros was large, comparable to in size to the largest living rhinoceros species, the white rh... | Biology and health sciences | Perissodactyla | Animals |
507190 | https://en.wikipedia.org/wiki/Steel%20and%20tin%20cans | Steel and tin cans | A steel can, tin can, tin (especially in British English, Australian English, Canadian English and South African English), or can is a container made of thin metal, for distribution or storage of goods. Some cans are opened by removing the top panel with a can opener or other tool; others have covers removable by hand... | Technology | Containers | null |
507709 | https://en.wikipedia.org/wiki/Azolla | Azolla | Azolla (common called mosquito fern, water fern, and fairy moss) is a genus of seven species of aquatic ferns in the family Salviniaceae. They are extremely reduced in form and specialized, looking nothing like other typical ferns but more resembling the form of some mosses or even duckweeds. Azolla filiculoides is one... | Biology and health sciences | Ferns | Plants |
507854 | https://en.wikipedia.org/wiki/Helium%20flash | Helium flash | A helium flash is a very brief thermal runaway nuclear fusion of large quantities of helium into carbon through the triple-alpha process in the core of low-mass stars (between 0.8 solar masses () and 2.0 ) during their red giant phase. The Sun is predicted to experience a flash 1.2 billion years after it leaves the mai... | Physical sciences | Stellar astronomy | Astronomy |
507960 | https://en.wikipedia.org/wiki/Solid%20geometry | Solid geometry | Solid geometry or stereometry is the geometry of three-dimensional Euclidean space (3D space).
A solid figure is the region of 3D space bounded by a two-dimensional closed surface; for example, a solid ball consists of a sphere and its interior.
Solid geometry deals with the measurements of volumes of various solids, ... | Mathematics | Three-dimensional space | null |
293758 | https://en.wikipedia.org/wiki/Loperamide | Loperamide | Loperamide, sold under the brand name Imodium, among others, is a medication of the opioid receptor agonist class used to decrease the frequency of diarrhea. It is often used for this purpose in irritable bowel syndrome, inflammatory bowel disease, short bowel syndrome, Crohn's disease, and ulcerative colitis. It is no... | Biology and health sciences | Specific drugs | Health |
293802 | https://en.wikipedia.org/wiki/Closure%20%28mathematics%29 | Closure (mathematics) | In mathematics, a subset of a given set is closed under an operation of the larger set if performing that operation on members of the subset always produces a member of that subset. For example, the natural numbers are closed under addition, but not under subtraction: is not a natural number, although both 1 and 2 are... | Mathematics | Set theory | null |
293921 | https://en.wikipedia.org/wiki/Seoul%20Metropolitan%20Subway | Seoul Metropolitan Subway | The Seoul Metropolitan Subway () is a metropolitan railway system consisting of 23 rapid transit, light metro, commuter rail and people mover lines located in northwest South Korea. The system serves most of the Seoul Metropolitan Area including the Incheon metropolis and satellite cities in Gyeonggi province. Some reg... | Technology | South Korea | null |
293961 | https://en.wikipedia.org/wiki/Aleph%20number | Aleph number | In mathematics, particularly in set theory, the aleph numbers are a sequence of numbers used to represent the cardinality (or size) of infinite sets that can be well-ordered. They were introduced by the mathematician Georg Cantor and are named after the symbol he used to denote them, the Hebrew letter aleph (ℵ).
The c... | Mathematics | Set theory | null |
294127 | https://en.wikipedia.org/wiki/Grains%20of%20paradise | Grains of paradise | Grains of paradise (Aframomum melegueta) is a species in the ginger family, Zingiberaceae, and closely related to cardamom. Its seeds are used as a spice (ground or whole); it imparts a pungent, black-pepper-like flavor with hints of citrus. It is also known as melegueta pepper, Guinea grains, ossame, or fom wisa, and... | Biology and health sciences | Herbs and spices | Plants |
294248 | https://en.wikipedia.org/wiki/Observable | Observable | In physics, an observable is a physical property or physical quantity that can be measured. In classical mechanics, an observable is a real-valued "function" on the set of all possible system states, e.g., position and momentum. In quantum mechanics, an observable is an operator, or gauge, where the property of the qua... | Physical sciences | Quantum mechanics | Physics |
294338 | https://en.wikipedia.org/wiki/Lead%20poisoning | Lead poisoning | Lead poisoning, also known as plumbism and saturnism, is a type of metal poisoning caused by lead in the body. Symptoms may include abdominal pain, constipation, headaches, irritability, memory problems, infertility, and tingling in the hands and feet. It causes almost 10% of intellectual disability of otherwise unknow... | Biology and health sciences | Types | Health |
294340 | https://en.wikipedia.org/wiki/Poisson%20bracket | Poisson bracket | In mathematics and classical mechanics, the Poisson bracket is an important binary operation in Hamiltonian mechanics, playing a central role in Hamilton's equations of motion, which govern the time evolution of a Hamiltonian dynamical system. The Poisson bracket also distinguishes a certain class of coordinate transfo... | Physical sciences | Classical mechanics | Physics |
294390 | https://en.wikipedia.org/wiki/Commutative%20property | Commutative property | In mathematics, a binary operation is commutative if changing the order of the operands does not change the result. It is a fundamental property of many binary operations, and many mathematical proofs depend on it. Perhaps most familiar as a property of arithmetic, e.g. or , the property can also be used in more advan... | Mathematics | Algebra | null |
294408 | https://en.wikipedia.org/wiki/Penrose%E2%80%93Hawking%20singularity%20theorems | Penrose–Hawking singularity theorems | The Penrose–Hawking singularity theorems (after Roger Penrose and Stephen Hawking) are a set of results in general relativity that attempt to answer the question of when gravitation produces singularities. The Penrose singularity theorem is a theorem in semi-Riemannian geometry and its general relativistic interpretati... | Physical sciences | Theory of relativity | Physics |
294419 | https://en.wikipedia.org/wiki/Sunscreen | Sunscreen | Sunscreen, also known as sunblock, sun lotion or sun cream, is a photoprotective topical product for the skin that helps protect against sunburn and prevent skin cancer. Sunscreens come as lotions, sprays, gels, foams (such as an expanded foam lotion or whipped lotion), sticks, powders and other topical products. Sunsc... | Biology and health sciences | Hygiene products | Health |
294656 | https://en.wikipedia.org/wiki/Andrology | Andrology | Andrology (from , anēr, genitive , andros 'man' and , -logia) is a name for the medical specialty that deals with male health, particularly relating to the problems of the male reproductive system and urological problems that are unique to men. It is the parallel to gynecology, which deals with medical issues which are... | Biology and health sciences | Fields of medicine | Health |
294752 | https://en.wikipedia.org/wiki/Quince | Quince | The quince (; Cydonia oblonga) is the sole member of the genus Cydonia in the Malinae subtribe (which contains apples, pears, and other fruits) of the Rosaceae family. It is a deciduous tree that bears hard, aromatic bright golden-yellow pome fruit, similar in appearance to a pear. Ripe quince fruits are hard, tart, an... | Biology and health sciences | Pomes | Plants |
294812 | https://en.wikipedia.org/wiki/Barbecue%20grill | Barbecue grill | A barbecue grill or barbeque grill (known as a barbecue or barbie in Australia and New Zealand) is a device that cooks food by applying heat from below. There are several varieties of grills, with most falling into one of three categories: gas-fueled, charcoal, or electric. There is debate over which method yields supe... | Technology | Household appliances | null |
294813 | https://en.wikipedia.org/wiki/Internet%20forum | Internet forum | An Internet forum, or message board, is an online discussion site where people can hold conversations in the form of posted messages. They differ from chat rooms in that messages are often longer than one line of text, and are at least temporarily archived. Also, depending on the access level of a user or the forum set... | Technology | Internet | null |
294943 | https://en.wikipedia.org/wiki/Carotenoid | Carotenoid | Carotenoids () are yellow, orange, and red organic pigments that are produced by plants and algae, as well as several bacteria, archaea, and fungi. Carotenoids give the characteristic color to pumpkins, carrots, parsnips, corn, tomatoes, canaries, flamingos, salmon, lobster, shrimp, and daffodils. Over 1,100 identified... | Biology and health sciences | Biochemistry and molecular biology | null |
294959 | https://en.wikipedia.org/wiki/Mistral%20%28wind%29 | Mistral (wind) | The mistral (, Corsican: maestrale, , , , ) is a strong, cold, northwesterly wind that blows from southern France into the Gulf of Lion in the northern Mediterranean. It produces sustained winds averaging 31 miles an hour (50 kilometres an hour), sometimes reaching 60 miles an hour (100 kilometres an hour). It can last... | Physical sciences | Winds | Earth science |
294995 | https://en.wikipedia.org/wiki/Euler%E2%80%93Lagrange%20equation | Euler–Lagrange equation | In the calculus of variations and classical mechanics, the Euler–Lagrange equations are a system of second-order ordinary differential equations whose solutions are stationary points of the given action functional. The equations were discovered in the 1750s by Swiss mathematician Leonhard Euler and Italian mathematicia... | Physical sciences | Classical mechanics | Physics |
295148 | https://en.wikipedia.org/wiki/Shoal | Shoal | In oceanography, geomorphology, and geoscience, a shoal is a natural submerged ridge, bank, or bar that consists of, or is covered by, sand or other unconsolidated material, and rises from the bed of a body of water close to the surface or above it, which poses a danger to navigation. Shoals are also known as sandbank... | Physical sciences | Oceanic and coastal landforms | Earth science |
295183 | https://en.wikipedia.org/wiki/Galilean%20transformation | Galilean transformation | In physics, a Galilean transformation is used to transform between the coordinates of two reference frames which differ only by constant relative motion within the constructs of Newtonian physics. These transformations together with spatial rotations and translations in space and time form the inhomogeneous Galilean gr... | Physical sciences | Classical mechanics | Physics |
295477 | https://en.wikipedia.org/wiki/Bowden%20cable | Bowden cable | A Bowden cable ( )
is a type of flexible cable used to transmit mechanical force or energy by the movement of an inner cable relative to a hollow outer cable housing. The housing is generally of composite construction, consisting of an inner lining, a longitudinally incompressible layer such as a helical winding or a... | Technology | Flexible components | null |
295670 | https://en.wikipedia.org/wiki/Urban%20ecology | Urban ecology | Urban ecology is the scientific study of the relation of living organisms with each other and their surroundings in an urban environment. An urban environment refers to environments dominated by high-density residential and commercial buildings, paved surfaces, and other urban-related factors that create a unique lands... | Biology and health sciences | Ecology | Biology |
295684 | https://en.wikipedia.org/wiki/Molybdenum%20disulfide | Molybdenum disulfide | Molybdenum disulfide (or moly) is an inorganic compound composed of molybdenum and sulfur. Its chemical formula is .
The compound is classified as a transition metal dichalcogenide. It is a silvery black solid that occurs as the mineral molybdenite, the principal ore for molybdenum. is relatively unreactive. It is un... | Physical sciences | Sulfide salts | Chemistry |
295829 | https://en.wikipedia.org/wiki/Reflection%20%28mathematics%29 | Reflection (mathematics) | In mathematics, a reflection (also spelled reflexion) is a mapping from a Euclidean space to itself that is an isometry with a hyperplane as the set of fixed points; this set is called the axis (in dimension 2) or plane (in dimension 3) of reflection. The image of a figure by a reflection is its mirror image in the axi... | Mathematics | Geometry: General | null |
295844 | https://en.wikipedia.org/wiki/Inversive%20geometry | Inversive geometry | In geometry, inversive geometry is the study of inversion, a transformation of the Euclidean plane that maps circles or lines to other circles or lines and that preserves the angles between crossing curves. Many difficult problems in geometry become much more tractable when an inversion is applied. Inversion seems to h... | Mathematics | Non-Euclidean geometry | null |
295971 | https://en.wikipedia.org/wiki/Wolframite | Wolframite | Wolframite is an iron, manganese, and tungstate mineral with a chemical formula of that is the intermediate mineral between ferberite ( rich) and hübnerite ( rich). Along with scheelite, the wolframite series are the most important tungsten ore minerals. Wolframite is found in quartz veins and pegmatites associated wi... | Physical sciences | Minerals | Earth science |
296445 | https://en.wikipedia.org/wiki/Impala | Impala | The impala or rooibok (Aepyceros melampus) is a medium-sized antelope found in eastern and southern Africa. The only extant member of the genus Aepyceros, and tribe Aepycerotini, it was first described to Europeans by German zoologist Hinrich Lichtenstein in 1812. Two subspecies are recognised—the grassland-dwelling co... | Biology and health sciences | Artiodactyla | null |
296542 | https://en.wikipedia.org/wiki/Chrysanthemum | Chrysanthemum | Chrysanthemums ( ), sometimes called mums or chrysanths, are flowering plants of the genus Chrysanthemum in the family Asteraceae. They are native to East Asia and northeastern Europe. Most species originate from East Asia, and the center of diversity is in China. Countless horticultural varieties and cultivars exist.
... | Biology and health sciences | Asterales | null |
296639 | https://en.wikipedia.org/wiki/Arrow%20of%20time | Arrow of time | The arrow of time, also called time's arrow, is the concept positing the "one-way direction" or "asymmetry" of time. It was developed in 1927 by the British astrophysicist Arthur Eddington, and is an unsolved general physics question. This direction, according to Eddington, could be determined by studying the organizat... | Physical sciences | Physics basics: General | Physics |
25453345 | https://en.wikipedia.org/wiki/Tropical%20year | Tropical year | A tropical year or solar year (or tropical period) is the time that the Sun takes to return to the same position in the sky – as viewed from the Earth or another celestial body of the Solar System – thus completing a full cycle of astronomical seasons. For example, it is the time from vernal equinox to the next vernal ... | Physical sciences | Celestial sphere: General | Astronomy |
25453500 | https://en.wikipedia.org/wiki/Coordinated%20Universal%20Time | Coordinated Universal Time | Coordinated Universal Time (UTC) is the primary time standard globally used to regulate clocks and time. It establishes a reference for the current time, forming the basis for civil time and time zones. UTC facilitates international communication, navigation, scientific research, and commerce.
UTC has been widely embr... | Technology | Timekeeping | null |
25453985 | https://en.wikipedia.org/wiki/Atomic%20clock | Atomic clock | An atomic clock is a clock that measures time by monitoring the resonant frequency of atoms. It is based on atoms having different energy levels. Electron states in an atom are associated with different energy levels, and in transitions between such states they interact with a very specific frequency of electromagnetic... | Technology | Timekeeping | null |
1942366 | https://en.wikipedia.org/wiki/Air%20quality%20index | Air quality index | An air quality index (AQI) is an indicator developed by government agencies to communicate to the public how polluted the air currently is or how polluted it is forecast to become. As air pollution levels rise, so does the AQI, along with the associated public health risk. Children, the elderly and individuals with res... | Physical sciences | Other_2 | Basics and measurement |
1945208 | https://en.wikipedia.org/wiki/Burgundy%20%28color%29 | Burgundy (color) | Burgundy is a purplish red.
The color burgundy takes its name from the Burgundy wine in France. When referring to the color, "burgundy" is not usually capitalized.
The color burgundy is similar to Bordeaux (Web color code #4C1C24), Merlot (#73343A), Berry (#A01641), and Redberry (#701f28). Burgundy is made of 50% r... | Physical sciences | Colors | Physics |
21059721 | https://en.wikipedia.org/wiki/Ulmus%20parvifolia | Ulmus parvifolia | Ulmus parvifolia, commonly known as the Chinese elm or lacebark elm, is a species native to eastern Asia, including China, India, Japan, Korea, and Vietnam. It has been described as "one of the most splendid elms, having the poise of a graceful Nothofagus".
Description
A small to medium deciduous or semideciduous (rar... | Biology and health sciences | Rosales | Plants |
6485164 | https://en.wikipedia.org/wiki/Aquaculture%20of%20catfish | Aquaculture of catfish | Catfish are easy to farm in warm climates, leading to inexpensive and safe food at local grocers. Catfish raised in inland tanks or channels are considered safe for the environment, since their waste and disease should be contained and not spread to the wild.
Asia
In Asia, many catfish species are important as food. S... | Technology | Aquaculture | null |
6487947 | https://en.wikipedia.org/wiki/Bullet%20Cluster | Bullet Cluster | The Bullet Cluster (1E 0657-56) consists of two colliding clusters of galaxies. Strictly speaking, the name Bullet Cluster refers to the smaller subcluster, moving away from the larger one. It is at a comoving radial distance of .
The object is of a particular note for astrophysicists, because gravitational lensing st... | Physical sciences | Notable galaxy clusters | Astronomy |
6493704 | https://en.wikipedia.org/wiki/D%C3%A9collement | Décollement | Décollement () is a gliding plane between two rock masses, also known as a basal detachment fault. Décollements are a deformational structure, resulting in independent styles of deformation in the rocks above and below the fault. They are associated with both compressional settings (involving folding and overthrusting... | Physical sciences | Tectonics | Earth science |
8453671 | https://en.wikipedia.org/wiki/Subtractor | Subtractor | In electronics, a subtractor – a digital circuit that performs subtraction of numbers – can be designed using the same approach as that of an adder. The binary subtraction process is summarized below. As with an adder, in the general case of calculations on multi-bit numbers, three bits are involved in performing the s... | Technology | Digital logic | null |
4946686 | https://en.wikipedia.org/wiki/Relative%20velocity | Relative velocity | The relative velocity of an object B relative to an observer A, denoted (also or ), is the velocity vector of B measured in the rest frame of A.
The relative speed is the vector norm of the relative velocity.
Classical mechanics
In one dimension (non-relativistic)
We begin with relative motion in the classical, (o... | Physical sciences | Classical mechanics | Physics |
4948091 | https://en.wikipedia.org/wiki/Port%20of%20New%20York%20and%20New%20Jersey | Port of New York and New Jersey | The Port of New York and New Jersey is the port district of the New York-Newark metropolitan area, encompassing the region within approximately a radius of the Statue of Liberty National Monument.
It includes the system of navigable waterways in the New York–New Jersey Harbor Estuary, which runs along over of shorel... | Technology | Specific piers and ports | null |
24066956 | https://en.wikipedia.org/wiki/Alluvial%20river | Alluvial river | An alluvial river is one in which the bed and banks are made up of mobile sediment and/or soil. Alluvial rivers are self-formed, meaning that their channels are shaped by the magnitude and frequency of the floods that they experience, and the ability of these floods to erode, deposit, and transport sediment. For this r... | Physical sciences | Hydrology | Earth science |
24066971 | https://en.wikipedia.org/wiki/Bedrock%20river | Bedrock river | A bedrock river is a river that has little to no alluvium mantling the bedrock over which it flows. However, most bedrock rivers are not pure forms; they are a combination of a bedrock channel and an alluvial channel. The way one can distinguish between bedrock rivers and alluvial rivers is through the extent of sedime... | Physical sciences | Hydrology | Earth science |
24071884 | https://en.wikipedia.org/wiki/Haneda%20Airport | Haneda Airport | , sometimes referred to as Tokyo-Haneda, is the busier of the two international airports serving the Greater Tokyo Area, the other one being Narita International Airport (NRT). It serves as the primary domestic base of Japan's two largest airlines, Japan Airlines (Terminal 1) and All Nippon Airways (Terminal 2), as wel... | Technology | Asia | null |
19973790 | https://en.wikipedia.org/wiki/Hawksbill%20sea%20turtle | Hawksbill sea turtle | The hawksbill sea turtle (Eretmochelys imbricata) is a critically endangered sea turtle belonging to the family Cheloniidae. It is the only extant species in the genus Eretmochelys. The species has a global distribution that is largely limited to tropical and subtropical marine and estuary ecosystems.
The appearance o... | Biology and health sciences | Turtles | Animals |
19975098 | https://en.wikipedia.org/wiki/Pull-apart%20basin | Pull-apart basin | In geology, a basin is a region where subsidence generates accommodation space for the deposition of sediments. A pull-apart basin is a structural basin where two overlapping (en echelon) strike-slip faults or a fault bend create an area of crustal extension undergoing tension, which causes the basin to sink down. Freq... | Physical sciences | Tectonics | Earth science |
26950550 | https://en.wikipedia.org/wiki/Type-cD%20galaxy | Type-cD galaxy | The type-cD galaxy (also cD-type galaxy, cD galaxy) is a galaxy morphology classification, a subtype of type-D giant elliptical galaxy. Characterized by a large halo of stars, they can be found near the centres of some rich galaxy clusters. They are also known as supergiant ellipticals or central dominant galaxies.
Ch... | Physical sciences | Galaxy classification | Astronomy |
26959489 | https://en.wikipedia.org/wiki/Tenaille | Tenaille | A tenaille (archaic tenalia) is an advanced defensive-work, in front of the main defences of a fortress, which takes its name from resemblance to the lip of a pair of pincers. It is "from French, literally: tongs, from Late Latin tenācula, pl of tenaculum".
In a letter to John Bradshaw, President of the Council of Sta... | Technology | Fortification | null |
21076226 | https://en.wikipedia.org/wiki/Plant%20tissue%20culture | Plant tissue culture | Plant tissue culture is a collection of techniques used to maintain or grow plant cells, tissues, or organs under sterile conditions on a nutrient culture medium of known composition. It is widely used to produce clones of a plant in a method known as micropropagation. Different techniques in plant tissue culture may o... | Technology | Biotechnology | null |
21076839 | https://en.wikipedia.org/wiki/Web%20page | Web page | A web page (or webpage) is a document on the Web that is accessed in a web browser. A website typically consists of many web pages linked together under a common domain name. The term "web page" is therefore a metaphor of paper pages bound together into a book.
Navigation
Each web page is identified by a distinct Un... | Technology | Internet | null |
3654207 | https://en.wikipedia.org/wiki/List%20of%20Chinese%20star%20names | List of Chinese star names | Chinese star names (Chinese: , xīng míng) are named according to ancient Chinese astronomy and astrology. The sky is divided into star mansions (, xīng xiù, also translated as "lodges") and asterisms (, xīng guān). The ecliptic is divided into four sectors that are associated with the Four Symbols, guardians in Chinese... | Physical sciences | Celestial sphere: General | Astronomy |
3656192 | https://en.wikipedia.org/wiki/Screw%20axis | Screw axis | A screw axis (helical axis or twist axis) is a line that is simultaneously the axis of rotation and the line along which translation of a body occurs. Chasles' theorem shows that each Euclidean displacement in three-dimensional space has a screw axis, and the displacement can be decomposed into a rotation about and a s... | Physical sciences | Basics_4 | Physics |
2694386 | https://en.wikipedia.org/wiki/Swietenia | Swietenia | Swietenia is a genus of trees in the chinaberry family, Meliaceae. It occurs natively in the Neotropics, from southern Florida, the Caribbean, Mexico and Central America south to Bolivia. The genus is named for Dutch-Austrian physician Gerard van Swieten (1700–1772). The wood of Swietenia trees is known as mahogany.
O... | Biology and health sciences | Sapindales | Plants |
2696466 | https://en.wikipedia.org/wiki/Demand%20response | Demand response | Demand response is a change in the power consumption of an electric utility customer to better match the demand for power with the supply. Until the 21st century decrease in the cost of pumped storage and batteries, electric energy could not be easily stored, so utilities have traditionally matched demand and supply by... | Technology | Electricity transmission and distribution | null |
6499752 | https://en.wikipedia.org/wiki/Electrical%20fault | Electrical fault | In an electric power system, a fault or fault current is any abnormal electric current. For example, a short circuit is a fault in which a live wire touches a neutral or ground wire. An open-circuit fault occurs if a circuit is interrupted by a failure of a current-carrying wire (phase or neutral) or a blown fuse or c... | Technology | Concepts | null |
6502961 | https://en.wikipedia.org/wiki/IAU%20definition%20of%20planet | IAU definition of planet | The International Astronomical Union (IAU) defined in August 2006 that, in the Solar System, a planet is a celestial body that:
is in orbit around the Sun,
has sufficient mass to assume hydrostatic equilibrium (a nearly round shape), and
has "cleared the neighbourhood" around its orbit.
A non-satellite body fulfill... | Physical sciences | Planetary science | Astronomy |
856761 | https://en.wikipedia.org/wiki/Muricidae | Muricidae | Muricidae is a large and varied taxonomic family of small to large predatory sea snails, marine gastropod mollusks, commonly known as murex snails or rock snails. With over 1,700 living species, the Muricidae represent almost 10% of the Neogastropoda. Additionally, 1,200 fossil species have been recognized. Numerous su... | Biology and health sciences | Gastropods | Animals |
857235 | https://en.wikipedia.org/wiki/Equivalence%20principle | Equivalence principle | The equivalence principle is the hypothesis that the observed equivalence of gravitational and inertial mass is a consequence of nature. The weak form, known for centuries, relates to masses of any composition in free fall taking the same trajectories and landing at identical times. The extended form by Albert Einstein... | Physical sciences | Theory of relativity | null |
858097 | https://en.wikipedia.org/wiki/Salt%20lake | Salt lake | A salt lake or saline lake is a landlocked body of water that has a concentration of salts (typically sodium chloride) and other dissolved minerals significantly higher than most lakes (often defined as at least three grams of salt per liter). In some cases, salt lakes have a higher concentration of salt than sea water... | Physical sciences | Hydrology | Earth science |
859077 | https://en.wikipedia.org/wiki/Beige | Beige | Beige is variously described as a pale sandy fawn color, a grayish tan, a light-grayish yellowish brown, or a pale to grayish yellow. It takes its name from French, where the word originally meant natural wool that has been neither bleached nor dyed, hence also the color of natural wool.
The word "beige" has come to ... | Physical sciences | Colors | Physics |
859275 | https://en.wikipedia.org/wiki/Displacement%20%28geometry%29 | Displacement (geometry) | In geometry and mechanics, a displacement is a vector whose length is the shortest distance from the initial to the final position of a point P undergoing motion. It quantifies both the distance and direction of the net or total motion along a straight line from the initial position to the final position of the point t... | Physical sciences | Basics_4 | Physics |
859283 | https://en.wikipedia.org/wiki/Cylinder | Cylinder | A cylinder () has traditionally been a three-dimensional solid, one of the most basic of curvilinear geometric shapes. In elementary geometry, it is considered a prism with a circle as its base.
A cylinder may also be defined as an infinite curvilinear surface in various modern branches of geometry and topology. The s... | Mathematics | Three-dimensional space | null |
859981 | https://en.wikipedia.org/wiki/Biochip | Biochip | In molecular biology, biochips are engineered substrates ("miniaturized laboratories") that can host large numbers of simultaneous biochemical reactions. One of the goals of biochip technology is to efficiently screen large numbers of biological analytes, with potential applications ranging from disease diagnosis to de... | Technology | Biotechnology | null |
860000 | https://en.wikipedia.org/wiki/Smokeless%20powder | Smokeless powder | Smokeless powder is a type of propellant used in firearms and artillery that produces less smoke and less fouling when fired compared to black powder. Because of their similar use, both the original black powder formulation and the smokeless propellant which replaced it are commonly described as gunpowder. The combusti... | Technology | Ammunition | null |
22576085 | https://en.wikipedia.org/wiki/Arrow%20pushing | Arrow pushing | Arrow pushing or electron pushing is a technique used to describe the progression of organic chemistry reaction mechanisms. It was first developed by Sir Robert Robinson. In using arrow pushing, "curved arrows" or "curly arrows" are drawn on the structural formulae of reactants in a chemical equation to show the react... | Physical sciences | Basics_3 | Chemistry |
1318086 | https://en.wikipedia.org/wiki/Revolutions%20per%20minute | Revolutions per minute | Revolutions per minute (abbreviated rpm, RPM, rev/min, r/min, or r⋅min−1) is a unit of rotational speed (or rotational frequency) for rotating machines.
One revolution per minute is equivalent to hertz.
Standards
ISO 80000-3:2019 defines a physical quantity called rotation (or number of revolutions), dimensionless, ... | Physical sciences | Angular velocity | Basics and measurement |
1318099 | https://en.wikipedia.org/wiki/Kronosaurus | Kronosaurus | Kronosaurus ( ) is an extinct genus of large short-necked pliosaur that lived during the Aptian to Albian stages of the Early Cretaceous in what is now Australia. The first known specimen was received in 1899 and consists of a partially preserved mandibular symphysis, which was first thought to come from an ichthyosaur... | Biology and health sciences | Prehistoric marine reptiles | Animals |
1319795 | https://en.wikipedia.org/wiki/Deinosuchus | Deinosuchus | Deinosuchus () is an extinct genus of alligatoroid crocodilian, related to modern alligators and caimans, that lived 82 to 73 million years ago (Ma), during the late Cretaceous period. The name translates as "terrible crocodile" and is derived from the Greek deinos (δεινός), "terrible", and soukhos (σοῦχος), "crocodile... | Biology and health sciences | Prehistoric crocodiles | Animals |
1320257 | https://en.wikipedia.org/wiki/Resplendent%20quetzal | Resplendent quetzal | The resplendent quetzal (Pharomachrus mocinno) is a small bird found in Central America and southern Mexico that lives in tropical forests, particularly montane cloud forests. They are part of the family Trogonidae and have two recognized subspecies, P. m. mocinno and P. m. costaricensis. Like other quetzals, the respl... | Biology and health sciences | Trogoniformes | null |
1324296 | https://en.wikipedia.org/wiki/Utility%20pole | Utility pole | A utility pole, commonly referred to as a transmission pole, telephone pole, telecommunication pole, power pole, hydro pole, telegraph pole, or telegraph post, is a column or post used to support overhead power lines and various other public utilities, such as electrical cable, fiber optic cable, and related equipment ... | Technology | Electricity transmission and distribution | null |
4955826 | https://en.wikipedia.org/wiki/Ara%20%28bird%29 | Ara (bird) | Ara is a Neotropical genus of macaws with eight extant species and at least two extinct species. The genus name was coined by French naturalist Bernard Germain de Lacépède in 1799. It gives its name to and is part of the Arini, or tribe of Neotropical parrots. The genus name Ara is derived from the Tupi word ará, an on... | Biology and health sciences | Psittaciformes | null |
4958097 | https://en.wikipedia.org/wiki/55%20Cancri%20e | 55 Cancri e | 55 Cancri e (abbreviated 55 Cnc e, also known as Janssen ) is an exoplanet orbiting a Sun-like host star, 55 Cancri A. The mass of the exoplanet is about eight Earth masses and its diameter is about twice that of the Earth. 55 Cancri e was discovered on 30 August 2004, thus making it the first super-Earth discovered ar... | Physical sciences | Notable exoplanets | Astronomy |
19980507 | https://en.wikipedia.org/wiki/Hybodontiformes | Hybodontiformes | Hybodontiformes, commonly called hybodonts, are an extinct group of shark-like cartilaginous fish (chondrichthyans) which existed from the late Devonian to the Late Cretaceous. Hybodonts share a close common ancestry with modern sharks and rays (Neoselachii) as part of the clade Euselachii. They are distinguished from ... | Biology and health sciences | Prehistoric chondrichthyans | Animals |
508239 | https://en.wikipedia.org/wiki/Trichromacy | Trichromacy | Trichromacy or trichromatism is the possession of three independent channels for conveying color information, derived from the three different types of cone cells in the eye. Organisms with trichromacy are called trichromats.
The normal explanation of trichromacy is that the organism's retina contains three types of c... | Biology and health sciences | Visual system | Biology |
508455 | https://en.wikipedia.org/wiki/Oxygen%20therapy | Oxygen therapy | Oxygen therapy, also referred to as supplemental oxygen, is the use of oxygen as medical treatment. Supplemental oxygen can also refer to the use of oxygen enriched air at altitude. Acute indications for therapy include hypoxemia (low blood oxygen levels), carbon monoxide toxicity and cluster headache. It may also be p... | Biology and health sciences | Treatments | Health |
508504 | https://en.wikipedia.org/wiki/Compressor | Compressor | A compressor is a mechanical device that increases the pressure of a gas by reducing its volume. An air compressor is a specific type of gas compressor.
Many compressors can be staged, that is, the gas is compressed several times in steps or stages, to increase discharge pressure. Often, the second stage is physically... | Technology | Hydraulics and pneumatics | null |
508602 | https://en.wikipedia.org/wiki/Reactivity%20%28chemistry%29 | Reactivity (chemistry) | In chemistry, reactivity is the impulse for which a chemical substance undergoes a chemical reaction, either by itself or with other materials, with an overall release of energy.
Reactivity refers to:
the chemical reactions of a single substance,
the chemical reactions of two or more substances that interact with ea... | Physical sciences | Reaction | Chemistry |
509033 | https://en.wikipedia.org/wiki/Rivet | Rivet | A rivet is a permanent mechanical fastener. Before being installed, a rivet consists of a smooth cylindrical shaft with a head on one end. The end opposite the head is called the tail. On installation, the deformed end is called the shop head or buck-tail.
Because there is effectively a head on each end of an installe... | Technology | Components_2 | null |
509042 | https://en.wikipedia.org/wiki/Ostracod | Ostracod | Ostracods, or ostracodes, are a class of the Crustacea (class Ostracoda), sometimes known as seed shrimp. Some 33,000 species (only 13,000 of which are extant) have been identified, grouped into 7 valid orders. They are small crustaceans, typically around in size, but varying from in the case of the marine Gigantocyp... | Biology and health sciences | Crustaceans | null |
509137 | https://en.wikipedia.org/wiki/Newtonian%20telescope | Newtonian telescope | The Newtonian telescope, also called the Newtonian reflector or just a Newtonian, is a type of reflecting telescope invented by the English scientist Sir Isaac Newton, using a concave primary mirror and a flat diagonal secondary mirror. Newton's first reflecting telescope was completed in 1668 and is the earliest known... | Technology | Telescope | null |
509748 | https://en.wikipedia.org/wiki/Parking%20lot | Parking lot | A parking lot or car park (British English), also known as a car lot, is a cleared area intended for parking vehicles. The term usually refers to an area dedicated only for parking, with a durable or semi-durable surface. In most jurisdictions where cars are the dominant mode of transportation, parking lots are a major... | Technology | Concepts of ground transport | null |
509871 | https://en.wikipedia.org/wiki/Pinus%20elliottii | Pinus elliottii | Pinus elliottii, commonly known as slash pine, is a conifer tree native to the Southeastern United States. Slash pine is named after the "slashes" – swampy ground overgrown with trees and bushes – that constitute its habitat. Other common names include swamp pine, yellow slash pine, and southern Florida pine. Slash pin... | Biology and health sciences | Pinaceae | Plants |
510060 | https://en.wikipedia.org/wiki/Intermediate-mass%20black%20hole | Intermediate-mass black hole | An intermediate-mass black hole (IMBH) is a class of black hole with mass in the range of one hundred to one hundred thousand (102–105) solar masses: significantly higher than stellar black holes but lower than the hundred thousand to more than one billion (105–109) solar mass supermassive black holes. Several IMBH can... | Physical sciences | Basics_2 | Astronomy |
510323 | https://en.wikipedia.org/wiki/Sumatran%20rhinoceros | Sumatran rhinoceros | The Sumatran rhinoceros (Dicerorhinus sumatrensis), also known as the Sumatran rhino, hairy rhinoceros or Asian two-horned rhinoceros, is a rare member of the family Rhinocerotidae and one of five extant species of rhinoceros; it is the only extant species of the genus Dicerorhinus. It is the smallest rhinoceros, altho... | Biology and health sciences | Perissodactyla | Animals |
510340 | https://en.wikipedia.org/wiki/Stellar%20black%20hole | Stellar black hole | A stellar black hole (or stellar-mass black hole) is a black hole formed by the gravitational collapse of a star. They have masses ranging from about 5 to several tens of solar masses. They are the remnants of supernova explosions, which may be observed as a type of gamma ray burst. These black holes are also referred ... | Physical sciences | Basics_2 | Astronomy |
511394 | https://en.wikipedia.org/wiki/Opioid | Opioid | Opioids are a class of drugs that derive from, or mimic, natural substances found in the opium poppy plant. Opioids work on opioid receptors in the brain and other organs to produce a variety of morphine-like effects, including pain relief.
The terms 'opioid' and 'opiate' are sometimes used interchangeably, but the te... | Biology and health sciences | Pain treatments | Health |
1947467 | https://en.wikipedia.org/wiki/Radical%20polymerization | Radical polymerization | In polymer chemistry, radical polymerization (RP) is a method of polymerization by which a polymer forms by the successive addition of a radical to building blocks (repeat units). Radicals can be formed by a number of different mechanisms, usually involving separate initiator molecules. Following its generation, the in... | Physical sciences | Organic reactions | Chemistry |
1948637 | https://en.wikipedia.org/wiki/Neuroplasticity | Neuroplasticity | Neuroplasticity, also known as neural plasticity or just plasticity, is the ability of neural networks in the brain to change through growth and reorganization. Neuroplasticity refers to the brain's ability to reorganize and rewire its neural connections, enabling it to adapt and function in ways that differ from its p... | Biology and health sciences | Biology basics | Biology |
1949009 | https://en.wikipedia.org/wiki/Heat%20capacity%20ratio | Heat capacity ratio | In thermal physics and thermodynamics, the heat capacity ratio, also known as the adiabatic index, the ratio of specific heats, or Laplace's coefficient, is the ratio of the heat capacity at constant pressure () to heat capacity at constant volume (). It is sometimes also known as the isentropic expansion factor and is... | Physical sciences | Thermodynamics | Physics |
1950552 | https://en.wikipedia.org/wiki/Wood%20frog | Wood frog | Lithobates sylvaticus or Rana sylvatica, commonly known as the wood frog, is a frog species that has a broad distribution over North America, extending from the boreal forest of the north to the southern Appalachians, with several notable disjunct populations including lowland eastern North Carolina. The wood frog has ... | Biology and health sciences | Frogs and toads | Animals |
1950766 | https://en.wikipedia.org/wiki/Graph%20isomorphism%20problem | Graph isomorphism problem | The graph isomorphism problem is the computational problem of determining whether two finite graphs are isomorphic.
The problem is not known to be solvable in polynomial time nor to be NP-complete, and therefore may be in the computational complexity class NP-intermediate. It is known that the graph isomorphism probl... | Mathematics | Graph theory | null |
1950953 | https://en.wikipedia.org/wiki/Crowbar | Crowbar | A crowbar, also called a wrecking bar, pry bar or prybar, pinch-bar, or occasionally a prise bar or prisebar, colloquially gooseneck, or pig bar, or in Australia a jemmy, is a lever consisting of a metal bar with a single curved end and flattened points, used to force two objects apart or gain mechanical advantage in ... | Technology | Hand tools | null |
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