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95465 | https://en.wikipedia.org/wiki/Stirling%20number | Stirling number | In mathematics, Stirling numbers arise in a variety of analytic and combinatorial problems. They are named after James Stirling, who introduced them in a purely algebraic setting in his book Methodus differentialis (1730). They were rediscovered and given a combinatorial meaning by Masanobu Saka in 1782.
Two different... | Mathematics | Combinatorics | null |
95807 | https://en.wikipedia.org/wiki/Radiography | Radiography | Radiography is an imaging technique using X-rays, gamma rays, or similar ionizing radiation and non-ionizing radiation to view the internal form of an object. Applications of radiography include medical ("diagnostic" radiography and "therapeutic radiography") and industrial radiography. Similar techniques are used in ... | Technology | Imaging | null |
19194676 | https://en.wikipedia.org/wiki/S-type%20star | S-type star | An S-type star (or just S star) is a cool giant with approximately equal quantities of carbon and oxygen in its atmosphere. The class was originally defined in 1922 by Paul Merrill for stars with unusual absorption lines and molecular bands now known to be due to s-process elements. The bands of zirconium monoxide (Z... | Physical sciences | Stellar astronomy | Astronomy |
19194778 | https://en.wikipedia.org/wiki/Deformation%20%28physics%29 | Deformation (physics) | In physics and continuum mechanics, deformation is the change in the shape or size of an object. It has dimension of length with SI unit of metre (m). It is quantified as the residual displacement of particles in a non-rigid body, from an configuration to a configuration, excluding the body's average translation and ... | Physical sciences | Fluid mechanics | Physics |
19196523 | https://en.wikipedia.org/wiki/Randomness | Randomness | In common usage, randomness is the apparent or actual lack of definite pattern or predictability in information. A random sequence of events, symbols or steps often has no order and does not follow an intelligible pattern or combination. Individual random events are, by definition, unpredictable, but if there is a know... | Mathematics | Probability | null |
14161438 | https://en.wikipedia.org/wiki/Polysporangiophyte | Polysporangiophyte | Polysporangiophytes, also called polysporangiates or formally Polysporangiophyta, are plants in which the spore-bearing generation (sporophyte) has branching stems (axes) that bear sporangia. The name literally means 'many sporangia plant'. The clade includes all land plants (embryophytes) except for the bryophytes (li... | Biology and health sciences | Vascular plants (except seed plants) | Plants |
3345164 | https://en.wikipedia.org/wiki/Pteropus | Pteropus | Pteropus (suborder Yinpterochiroptera) is a genus of megabats which are among the largest bats in the world. They are commonly known as fruit bats or flying foxes, among other colloquial names.
They live in South Asia, Southeast Asia, Australia, East Africa, and some oceanic islands in the Indian and Pacific Oceans.
... | Biology and health sciences | Bats | null |
3345336 | https://en.wikipedia.org/wiki/Riparian%20zone | Riparian zone | A riparian zone or riparian area is the interface between land and a river or stream. In some regions, the terms riparian woodland, riparian forest, riparian buffer zone, riparian corridor, and riparian strip are used to characterize a riparian zone. The word riparian is derived from Latin ripa, meaning "river bank".
... | Physical sciences | Wetlands | Earth science |
15261560 | https://en.wikipedia.org/wiki/Dictyostelium%20discoideum | Dictyostelium discoideum | Dictyostelium discoideum is a species of soil-dwelling amoeba belonging to the phylum Amoebozoa, infraphylum Mycetozoa. Commonly referred to as slime mold, D. discoideum is a eukaryote that transitions from a collection of unicellular amoebae into a multicellular slug and then into a fruiting body within its lifetime. ... | Biology and health sciences | Eukaryotes | Plants |
712345 | https://en.wikipedia.org/wiki/Debridement | Debridement | Debridement is the medical removal of dead, damaged, or infected tissue to improve the healing potential of the remaining healthy tissue. Removal may be surgical, mechanical, chemical, autolytic (self-digestion), or by maggot therapy.
In podiatry, practitioners such as chiropodists, podiatrists and foot health practit... | Biology and health sciences | Surgery | Health |
712576 | https://en.wikipedia.org/wiki/Passive%20smoking | Passive smoking | Passive smoking is the inhalation of tobacco smoke, called passive smoke, secondhand smoke (SHS) or environmental tobacco smoke (ETS), by individuals other than the active smoker. It occurs when tobacco smoke diffuses into the surrounding atmosphere as an aerosol pollutant, which leads to its inhalation by nearby bysta... | Biology and health sciences | Health and fitness: General | Health |
712625 | https://en.wikipedia.org/wiki/Scree | Scree | Scree is a collection of broken rock fragments at the base of a cliff or other steep rocky mass that has accumulated through periodic rockfall. Landforms associated with these materials are often called talus deposits.
The term scree is applied both to an unstable steep mountain slope composed of rock fragments and ot... | Physical sciences | Montane landforms | Earth science |
712675 | https://en.wikipedia.org/wiki/Operator%20theory | Operator theory | In mathematics, operator theory is the study of linear operators on function spaces, beginning with differential operators and integral operators. The operators may be presented abstractly by their characteristics, such as bounded linear operators or closed operators, and consideration may be given to nonlinear operato... | Mathematics | Mathematical analysis | null |
712694 | https://en.wikipedia.org/wiki/Push-up | Push-up | The push-up (press-up in British English) is a common calisthenics exercise beginning from the prone position. By raising and lowering the body using the arms, push-ups exercise the pectoral muscles, triceps, and anterior deltoids, with ancillary benefits to the rest of the deltoids, serratus anterior, coracobrachialis... | Biology and health sciences | Physical fitness | Health |
712760 | https://en.wikipedia.org/wiki/Trichoplax | Trichoplax | Trichoplax adhaerens is one of the four named species in the phylum Placozoa. The others are Hoilungia hongkongensis, Polyplacotoma mediterranea and Cladtertia collaboinventa. Placozoa is a basal group of multicellular animals, possible relatives of Cnidaria. Trichoplax are very flat organisms commonly less than 4 mm i... | Biology and health sciences | Other | Animals |
713497 | https://en.wikipedia.org/wiki/Wireless%20mesh%20network | Wireless mesh network | A wireless mesh network (WMN) is a communications network made up of radio nodes organized in a mesh topology. It can also be a form of wireless ad hoc network.
A mesh refers to rich interconnection among devices or nodes. Wireless mesh networks often consist of mesh clients, mesh routers and gateways. Mobility of nod... | Technology | Networks | null |
713903 | https://en.wikipedia.org/wiki/Taipan | Taipan | Taipans are snakes of the genus Oxyuranus in the elapid family. They are large, fast-moving, highly venomous, and endemic to Australia and New Guinea. Three species are recognised, one of which, the coastal taipan, has two subspecies. Taipans are some of the deadliest known snakes.
Taxonomy
The common name, taipan, wa... | Biology and health sciences | Snakes | Animals |
714543 | https://en.wikipedia.org/wiki/Br%C3%B8nsted%E2%80%93Lowry%20acid%E2%80%93base%20theory | Brønsted–Lowry acid–base theory | The Brønsted–Lowry theory (also called proton theory of acids and bases) is an acid–base reaction theory which was first developed by Johannes Nicolaus Brønsted and Thomas Martin Lowry independently in 1923. The basic concept of this theory is that when an acid and a base react with each other, the acid forms its conju... | Physical sciences | Concepts | Chemistry |
714710 | https://en.wikipedia.org/wiki/Weber%20%28unit%29 | Weber (unit) | In physics, the weber ( ; symbol: Wb) is the unit of magnetic flux in the International System of Units (SI). The unit is derived (through Faraday's law of induction) from the relationship (volt-second). A magnetic flux density of 1 Wb/m2 (one weber per square metre) is one tesla.
The weber is named after the German ... | Physical sciences | Electromagnetism | null |
714908 | https://en.wikipedia.org/wiki/Ridge | Ridge | A ridge is a long, narrow, elevated geomorphologic landform, structural feature, or a combination of both separated from the surrounding terrain by steep sides. The sides of a ridge slope away from a narrow top, the crest or ridgecrest, with the terrain dropping down on either side. The crest, if narrow, is also called... | Physical sciences | Montane landforms | Earth science |
715028 | https://en.wikipedia.org/wiki/Chain%20%28unit%29 | Chain (unit) | The chain (abbreviated ch) is a unit of length equal to 66 feet (22 yards), used in both the US customary and Imperial unit systems. It is subdivided into 100 links. There are 10 chains in a furlong, and 80 chains in one statute mile. In metric terms, it is 20.1168 m long. By extension, chainage (running distance) is t... | Physical sciences | English | Basics and measurement |
715308 | https://en.wikipedia.org/wiki/Whirlpool%20Galaxy | Whirlpool Galaxy | The Whirlpool Galaxy, also known as Messier 51a (M51a) or NGC 5194, is an interacting grand-design spiral galaxy with a Seyfert 2 active galactic nucleus. It lies in the constellation Canes Venatici, and was the first galaxy to be classified as a spiral galaxy. It is 31 million lightyears (9.5 megaparsecs/Mpc) away and... | Physical sciences | Notable galaxies | null |
715446 | https://en.wikipedia.org/wiki/Picea%20sitchensis | Picea sitchensis | Picea sitchensis, the Sitka spruce, is a large, coniferous, evergreen tree growing to just over tall, with a trunk diameter at breast height that can exceed 5 m (16 ft). It is by far the largest species of spruce and the fifth-largest conifer in the world (behind giant sequoia, coast redwood, kauri, and western red ce... | Biology and health sciences | Pinaceae | Plants |
715930 | https://en.wikipedia.org/wiki/Cider%20apple | Cider apple | Cider apples are a group of apple cultivars grown for their use in the production of cider (referred to as "hard cider" in the United States). Cider apples are distinguished from "cookers" and "eaters", or dessert apples, by their bitterness or dryness of flavour, qualities which make the fruit unpalatable but can be u... | Biology and health sciences | Pomes | Plants |
715934 | https://en.wikipedia.org/wiki/Snakebite | Snakebite | A snakebite is an injury caused by the bite of a snake, especially a venomous snake. A common sign of a bite from a venomous snake is the presence of two puncture wounds from the animal's fangs. Sometimes venom injection from the bite may occur. This may result in redness, swelling, and severe pain at the area, which m... | Biology and health sciences | Types | Health |
716184 | https://en.wikipedia.org/wiki/JAXA | JAXA | The is the Japanese national air and space agency. Through the merger of three previously independent organizations, JAXA was formed on 1 October 2003. JAXA is responsible for research, technology development and launch of satellites into orbit, and is involved in many more advanced missions such as asteroid explorati... | Technology | Programs and launch sites | null |
716422 | https://en.wikipedia.org/wiki/16-cell | 16-cell | In geometry, the 16-cell is the regular convex 4-polytope (four-dimensional analogue of a Platonic solid) with Schläfli symbol {3,3,4}. It is one of the six regular convex 4-polytopes first described by the Swiss mathematician Ludwig Schläfli in the mid-19th century. It is also called C16, hexadecachoron, or hexdecahed... | Mathematics | Four-dimensional space | null |
16976158 | https://en.wikipedia.org/wiki/Notosuchia | Notosuchia | Notosuchia is a suborder of primarily Gondwanan mesoeucrocodylian crocodylomorphs that lived during the Jurassic and Cretaceous. Some phylogenies recover Sebecosuchia as a clade within Notosuchia, others as a sister group (see below); if Sebecosuchia is included within Notosuchia its existence is pushed into the Middle... | Biology and health sciences | Prehistoric crocodiles | Animals |
4533924 | https://en.wikipedia.org/wiki/Binary%20multiplier | Binary multiplier | A binary multiplier is an electronic circuit used in digital electronics, such as a computer, to multiply two binary numbers.
A variety of computer arithmetic techniques can be used to implement a digital multiplier. Most techniques involve computing the set of partial products, which are then summed together using bi... | Technology | Digital logic | null |
4535852 | https://en.wikipedia.org/wiki/Carbon%20sequestration | Carbon sequestration | Carbon sequestration is the process of storing carbon in a carbon pool. It plays a crucial role in limiting climate change by reducing the amount of carbon dioxide in the atmosphere. There are two main types of carbon sequestration: biologic (also called biosequestration) and geologic.
Biologic carbon sequestration ... | Physical sciences | Earth science basics: General | Earth science |
1157422 | https://en.wikipedia.org/wiki/Virial%20expansion | Virial expansion | The virial expansion is a model of thermodynamic equations of state. It expresses the pressure of a gas in local equilibrium as a power series of the density. This equation may be represented in terms of the compressibility factor, , as
This equation was first proposed by Kamerlingh Onnes. The terms , , and represen... | Physical sciences | Thermodynamics | Physics |
1157601 | https://en.wikipedia.org/wiki/Rake%20%28tool%29 | Rake (tool) | A rake (Old English raca, cognate with Dutch hark, German Rechen, from the root meaning "to scrape together", "heap up") is a broom for outside use; a horticultural implement consisting of a toothed bar fixed transversely to a handle, or tines fixed to a handle, and used to collect leaves, hay, grass, etc., and in gard... | Technology | Agricultural tools | null |
1157828 | https://en.wikipedia.org/wiki/ROSAT | ROSAT | ROSAT (short for Röntgensatellit; in German X-rays are called Röntgenstrahlen, in honour of Wilhelm Röntgen) was a German Aerospace Center-led satellite X-ray telescope, with instruments built by West Germany, the United Kingdom and the United States. It was launched on 1 June 1990, on a Delta II rocket from Cape Canav... | Technology | Space-based observatories | null |
1157853 | https://en.wikipedia.org/wiki/Bellis%20perennis | Bellis perennis | Bellis perennis (), the daisy, is a European species of the family Asteraceae, often considered the archetypal species of the name daisy. To distinguish this species from other plants known as daisies, it is sometimes qualified or known as common daisy, lawn daisy or English daisy.
Description
Bellis perennis is a per... | Biology and health sciences | Asterales | null |
1158125 | https://en.wikipedia.org/wiki/DNA%20sequencing | DNA sequencing | DNA sequencing is the process of determining the nucleic acid sequence – the order of nucleotides in DNA. It includes any method or technology that is used to determine the order of the four bases: adenine, guanine, cytosine, and thymine. The advent of rapid DNA sequencing methods has greatly accelerated biological and... | Biology and health sciences | Genetics | Biology |
1158235 | https://en.wikipedia.org/wiki/Debye%20length | Debye length | In plasmas and electrolytes, the Debye length (Debye radius or Debye–Hückel screening length), is a measure of a charge carrier's net electrostatic effect in a solution and how far its electrostatic effect persists. With each Debye length the charges are increasingly electrically screened and the electric potential d... | Physical sciences | Electrostatics | Physics |
1160429 | https://en.wikipedia.org/wiki/Foreshock | Foreshock | A foreshock is an earthquake that occurs before a larger seismic eventthe mainshockand is related to it in both time and space. The designation of an earthquake as foreshock, mainshock or aftershock is only possible after the full sequence of events has happened.
Occurrence
Foreshock activity has been detected for abo... | Physical sciences | Seismology | Earth science |
1161453 | https://en.wikipedia.org/wiki/Clay%20mineral | Clay mineral | Clay minerals are hydrous aluminium phyllosilicates (e.g. kaolin, Al2Si2O5(OH)4), sometimes with variable amounts of iron, magnesium, alkali metals, alkaline earths, and other cations found on or near some planetary surfaces.
Clay minerals form in the presence of water and have been important to life, and many theorie... | Physical sciences | Silicate minerals | Earth science |
2444759 | https://en.wikipedia.org/wiki/Shrimpfish | Shrimpfish | Shrimpfish, also called razorfish, are five small species of marine fishes in the subfamily Centriscinae of the family Centriscidae. The species in the genera Aeoliscus and Centriscus are found in relatively shallow tropical parts of the Indo-Pacific, while the banded bellowsfish, which often is placed in the subfamily... | Biology and health sciences | Acanthomorpha | Animals |
2445877 | https://en.wikipedia.org/wiki/Bastion%20fort | Bastion fort | A bastion fort or trace italienne (a phrase derived from non-standard French, meaning 'Italian outline') is a fortification in a style developed during the early modern period in response to the ascendancy of gunpowder weapons such as cannon, which rendered earlier medieval approaches to fortification obsolete. It appe... | Technology | Fortification | null |
1762926 | https://en.wikipedia.org/wiki/Molecular%20machine | Molecular machine | Molecular machines are a class of molecules typically described as an assembly of a discrete number of molecular components intended to produce mechanical movements in response to specific stimuli, mimicking macromolecular devices such as switches and motors. Naturally occurring or biological molecular machines are re... | Technology | Basics | null |
1763424 | https://en.wikipedia.org/wiki/Turbidity%20current | Turbidity current | A turbidity current is most typically an underwater current of usually rapidly moving, sediment-laden water moving down a slope; although current research (2018) indicates that water-saturated sediment may be the primary actor in the process. Turbidity currents can also occur in other fluids besides water.
Researcher... | Physical sciences | Oceanography | Earth science |
1764276 | https://en.wikipedia.org/wiki/Autobahn | Autobahn | The (; German , ) is the federal controlled-access highway system in Germany. The official term is (abbreviated BAB), which translates as 'federal motorway'. The literal meaning of the word is 'Federal Auto(mobile) Track'.
Much of the system has no speed limit for some classes of vehicles. However, limits are poste... | Technology | Ground transportation networks | null |
1765204 | https://en.wikipedia.org/wiki/Fuji%20%28apple%29 | Fuji (apple) | The is an apple cultivar developed by growers at the in Fujisaki, Aomori, Japan, in the late 1930s, and brought to market in 1962. It originated as a cross between two American apple varieties—the Red Delicious and old Virginia Ralls Janet (sometimes cited as "Rawls Jennet") apples. According to the US Apple Associat... | Biology and health sciences | Pomes | Plants |
1765281 | https://en.wikipedia.org/wiki/Climate%20sensitivity | Climate sensitivity | Climate sensitivity is a key measure in climate science and describes how much Earth's surface will warm for a doubling in the atmospheric carbon dioxide () concentration. Its formal definition is: "The change in the surface temperature in response to a change in the atmospheric carbon dioxide (CO2) concentration or ot... | Physical sciences | Climate change | Earth science |
1765503 | https://en.wikipedia.org/wiki/Water%20deer | Water deer | The water deer (Hydropotes inermis) is a small deer species native to Korea and China. Its prominent tusks, similar to those of musk deer, have led to both subspecies being colloquially named vampire deer in English-speaking areas to which they have been imported. It was first described to the Western world by Robert S... | Biology and health sciences | Deer | Animals |
1765998 | https://en.wikipedia.org/wiki/Wildlife%20conservation | Wildlife conservation | Wildlife conservation refers to the practice of protecting wild species and their habitats in order to maintain healthy wildlife species or populations and to restore, protect or enhance natural ecosystems. Major threats to wildlife include habitat destruction, degradation, fragmentation, overexploitation, poaching, po... | Biology and health sciences | Ecology | null |
1767352 | https://en.wikipedia.org/wiki/Taung%20Child | Taung Child | The Taung Child (or Taung Baby) is the fossilised skull of a young Australopithecus africanus. It was discovered in 1924 by quarrymen working for the Northern Lime Company in Taung, South Africa. Raymond Dart described it as a new species in the journal Nature in 1925.
The Taung skull is in repository at the Universit... | Biology and health sciences | Australopithecines | Biology |
19210530 | https://en.wikipedia.org/wiki/Browsing%20%28herbivory%29 | Browsing (herbivory) | Browsing is a type of herbivory in which a herbivore (or, more narrowly defined, a folivore) feeds on leaves, soft shoots, or fruits of high-growing, generally woody plants such as shrubs. This is contrasted with grazing, usually associated with animals feeding on grass or other lower vegetations. Alternatively, graze... | Biology and health sciences | Ethology | Biology |
19217674 | https://en.wikipedia.org/wiki/Mawsonia%20%28fish%29 | Mawsonia (fish) | Mawsonia is an extinct genus of prehistoric coelacanth fish. It is amongst the largest of all coelacanths, with one quadrate specimen (DGM 1.048-P) possibly belonging to an individual measuring in length. It lived in freshwater and brackish environments from the late Jurassic to the mid-Cretaceous (Kimmeridgian to Cen... | Biology and health sciences | Prehistoric osteichthyans | Animals |
5980254 | https://en.wikipedia.org/wiki/Desert%20farming | Desert farming | Desert farming is the practice of developing agriculture in deserts. As agriculture depends upon irrigation and water supply, farming in arid regions where water is scarce is a challenge. However, desert farming has been practiced by humans for thousands of years. In the Negev, there is evidence to suggest agricultu... | Technology | Agriculture_2 | null |
3350402 | https://en.wikipedia.org/wiki/Cuckoo%20bee | Cuckoo bee | The term cuckoo bee is used for a variety of different bee lineages which have evolved the kleptoparasitic behaviour of laying their eggs in the nests of other bees, reminiscent of the behavior of cuckoo birds. The name is perhaps best applied to the apid subfamily Nomadinae, but is sometimes used in Europe to mean bum... | Biology and health sciences | Hymenoptera | Animals |
3352423 | https://en.wikipedia.org/wiki/Hydrogen%20fluoride | Hydrogen fluoride | Hydrogen fluoride (fluorane) is an inorganic compound with chemical formula . It is a very poisonous, colorless gas or liquid that dissolves in water to yield hydrofluoric acid. It is the principal industrial source of fluorine, often in the form of hydrofluoric acid, and is an important feedstock in the preparation of... | Physical sciences | Hydrogen compounds | Chemistry |
3352536 | https://en.wikipedia.org/wiki/Exotic%20star | Exotic star | An exotic star is a hypothetical compact star composed of exotic matter (something not made of electrons, protons, neutrons, or muons), and balanced against gravitational collapse by degeneracy pressure or other quantum properties.
Types of exotic stars include
quark stars (composed of quarks)
strange stars (compos... | Physical sciences | Stellar astronomy | Astronomy |
12502446 | https://en.wikipedia.org/wiki/Fairchild%20Republic%20A-10%20Thunderbolt%20II | Fairchild Republic A-10 Thunderbolt II | The Fairchild Republic A-10 Thunderbolt II is a single-seat, twin-turbofan, straight-wing, subsonic attack aircraft developed by Fairchild Republic for the United States Air Force (USAF). In service since 1977, it is named after the Republic P-47 Thunderbolt, but is commonly referred to as the "Warthog" or simply "Hog"... | Technology | Specific aircraft | null |
4543466 | https://en.wikipedia.org/wiki/Future%20Air%20Navigation%20System | Future Air Navigation System | The Future Air Navigation System (FANS) is an avionics system which provides direct data link communication between the pilot and the air traffic controller. The communications include air traffic control clearances, pilot requests and position reporting. In the FANS-B equipped Airbus A320 family aircraft, an Air Traff... | Technology | Aircraft components | null |
4544079 | https://en.wikipedia.org/wiki/Songket | Songket | Songket or sungkit is a tenun fabric that belongs to the brocade family of textiles of Brunei, Indonesia, and Malaysia. It is hand-woven in silk or cotton, and intricately patterned with gold or silver threads. The metallic threads stand out against the background cloth to create a shimmering effect. In the weaving pro... | Technology | Weaving | null |
4546155 | https://en.wikipedia.org/wiki/Structural%20basin | Structural basin | A structural basin is a large-scale structural formation of rock strata formed by tectonic warping (folding) of previously flat-lying strata into a syncline fold. They are geological depressions, the inverse of domes. Elongated structural basins are a type of geological trough. Some structural basins are sedimentary ba... | Physical sciences | Structural geology | Earth science |
420229 | https://en.wikipedia.org/wiki/Sarcomere | Sarcomere | A sarcomere (Greek σάρξ sarx "flesh", μέρος meros "part") is the smallest functional unit of striated muscle tissue. It is the repeating unit between two Z-lines. Skeletal muscles are composed of tubular muscle cells (called muscle fibers or myofibers) which are formed during embryonic myogenesis. Muscle fibers contai... | Biology and health sciences | Muscular system | null |
420275 | https://en.wikipedia.org/wiki/Galactic%20bulge | Galactic bulge | In astronomy, a galactic bulge (or simply bulge) is a tightly packed group of stars within a larger star formation. The term almost exclusively refers to the central group of stars found in most spiral galaxies (see galactic spheroid). Bulges were historically thought to be elliptical galaxies that happened to have a d... | Physical sciences | Basics_2 | Astronomy |
420661 | https://en.wikipedia.org/wiki/False%20killer%20whale | False killer whale | The false killer whale (Pseudorca crassidens) is a species of oceanic dolphin that is the only extant representative of the genus Pseudorca. It is found in oceans worldwide but mainly in tropical regions. It was first described in 1846 as a species of porpoise based on a skull, which was revised when the first carcasse... | Biology and health sciences | Toothed whale | Animals |
420732 | https://en.wikipedia.org/wiki/Ground%20squirrel | Ground squirrel | Ground squirrels are rodents of the squirrel family (Sciuridae) that generally live on the ground or in burrows, rather than in trees like the tree squirrels. The term is most often used for the medium-sized ground squirrels, as the larger ones are more commonly known as marmots (genus Marmota) or prairie dogs, while t... | Biology and health sciences | Rodents | Animals |
420764 | https://en.wikipedia.org/wiki/Integrated%20pest%20management | Integrated pest management | Integrated pest management (IPM), also known as integrated pest control (IPC) that integrates both chemical and non-chemical practices for economic control of pests. The UN's Food and Agriculture Organization defines IPM as "the careful consideration of all available pest control techniques and subsequent integration o... | Technology | Pest and disease control | null |
420944 | https://en.wikipedia.org/wiki/Vampire%20squid | Vampire squid | The vampire squid (Vampyroteuthis infernalis, lit. 'vampire squid from hell') is a small cephalopod found throughout temperate and tropical oceans in extreme deep sea conditions. The vampire squid uses its bioluminescent organs and its unique oxygen metabolism to thrive in the parts of the ocean with the lowest concent... | Biology and health sciences | Cephalopods | Animals |
421049 | https://en.wikipedia.org/wiki/Spirit%20%28rover%29 | Spirit (rover) | Spirit, also known as MER-A (Mars Exploration Rover – A) or MER-2, is a Mars robotic rover, active from 2004 to 2010. Spirit was operational on Mars for sols or 3.3 Martian years ( days; ). It was one of two rovers of NASA's Mars Exploration Rover Mission managed by the Jet Propulsion Laboratory (JPL). Spirit landed s... | Technology | Rovers | null |
421051 | https://en.wikipedia.org/wiki/Opportunity%20%28rover%29 | Opportunity (rover) | Opportunity, also known as MER-B (Mars Exploration Rover – B) or MER-1, and nicknamed Oppy, is a robotic rover that was active on Mars from 2004 until 2018. Opportunity was operational on Mars for sols ( on Earth). Launched on July 7, 2003, as part of NASA's Mars Exploration Rover program, it landed in Meridiani Planu... | Technology | Rovers | null |
421068 | https://en.wikipedia.org/wiki/Prenex%20normal%20form | Prenex normal form | A formula of the predicate calculus is in prenex normal form (PNF) if it is written as a string of quantifiers and bound variables, called the prefix, followed by a quantifier-free part, called the matrix. Together with the normal forms in propositional logic (e.g. disjunctive normal form or conjunctive normal form), i... | Mathematics | Mathematical logic | null |
421074 | https://en.wikipedia.org/wiki/Skolem%20normal%20form | Skolem normal form | In mathematical logic, a formula of first-order logic is in Skolem normal form if it is in prenex normal form with only universal first-order quantifiers.
Every first-order formula may be converted into Skolem normal form while not changing its satisfiability via a process called Skolemization (sometimes spelled Skol... | Mathematics | Mathematical logic | null |
421366 | https://en.wikipedia.org/wiki/Mars%20rover | Mars rover | A Mars rover is a remote-controlled motor vehicle designed to travel on the surface of Mars. Rovers have several advantages over stationary landers: they examine more territory, they can be directed to interesting features, they can place themselves in sunny positions to weather winter months, and they can advance the ... | Technology | Rovers | null |
421517 | https://en.wikipedia.org/wiki/Dobsonian%20telescope | Dobsonian telescope | A Dobsonian telescope is an altazimuth-mounted Newtonian telescope design popularized by John Dobson in 1965 and credited with vastly increasing the size of telescopes available to amateur astronomers. Dobson's telescopes featured a simplified mechanical design that was easy to manufacture from readily available compon... | Technology | Telescope | null |
421940 | https://en.wikipedia.org/wiki/Bragg%27s%20law | Bragg's law | In many areas of science, Bragg's law, Wulff–Bragg's condition, or Laue–Bragg interference are a special case of Laue diffraction, giving the angles for coherent scattering of waves from a large crystal lattice. It describes how the superposition of wave fronts scattered by lattice planes leads to a strict relation bet... | Physical sciences | Waves | Physics |
422180 | https://en.wikipedia.org/wiki/Telescope%20mount | Telescope mount | A telescope mount is a mechanical structure which supports a telescope. Telescope mounts are designed to support the mass of the telescope and allow for accurate pointing of the instrument. Many sorts of mounts have been developed over the years, with the majority of effort being put into systems that can track the mot... | Technology | Telescope | null |
422328 | https://en.wikipedia.org/wiki/Napkin | Napkin | A napkin, serviette or face towelette is a square of cloth or paper tissue used at the table for wiping the mouth and fingers while eating. It is also sometimes used as a bib by tucking it into a shirt collar. It is usually small and folded, sometimes in intricate designs and shapes.
Etymology and terminology
The ter... | Biology and health sciences | Hygiene products | Health |
422481 | https://en.wikipedia.org/wiki/Mass%E2%80%93energy%20equivalence | Mass–energy equivalence | In physics, mass–energy equivalence is the relationship between mass and energy in a system's rest frame, where the two quantities differ only by a multiplicative constant and the units of measurement. The principle is described by the physicist Albert Einstein's formula: . In a reference frame where the system is movi... | Physical sciences | Basics_6 | null |
422569 | https://en.wikipedia.org/wiki/Galena | Galena | Galena, also called lead glance, is the natural mineral form of lead(II) sulfide (PbS). It is the most important ore of lead and an important source of silver.
Galena is one of the most abundant and widely distributed sulfide minerals. It crystallizes in the cubic crystal system often showing octahedral forms. It is o... | Physical sciences | Minerals | Earth science |
422698 | https://en.wikipedia.org/wiki/Decomposer | Decomposer | Decomposers are organisms that break down dead organisms and release the nutrients from the dead matter into the environment around them. Decomposition relies on chemical processes similar to digestion in animals; in fact, many sources use the words digestion and decomposition interchangeably. In both processes, comple... | Biology and health sciences | Ecology | Biology |
422936 | https://en.wikipedia.org/wiki/Vector%20potential | Vector potential | In vector calculus, a vector potential is a vector field whose curl is a given vector field. This is analogous to a scalar potential, which is a scalar field whose gradient is a given vector field.
Formally, given a vector field , a vector potential is a vector field such that
Consequence
If a vector field admits ... | Physical sciences | Classical mechanics | Physics |
423063 | https://en.wikipedia.org/wiki/Season%20extension | Season extension | Season extension in agriculture is any method that allows a crop to be grown beyond its normal outdoor growing season and harvesting time frame, or the extra time thus achieved. To extend the growing season into the colder months, one can use unheated techniques such as floating row covers, low tunnels, caterpillar tun... | Technology | Basics_2 | null |
15295535 | https://en.wikipedia.org/wiki/Snow%20leopard | Snow leopard | The snow leopard (Panthera uncia) is a species of large cat in the genus Panthera of the family Felidae. The species is native to the mountain ranges of Central and South Asia. It is listed as Vulnerable on the IUCN Red List because the global population is estimated to number fewer than 10,000 mature individuals and i... | Biology and health sciences | Carnivora | null |
15296588 | https://en.wikipedia.org/wiki/Linear%20molecular%20geometry | Linear molecular geometry | The linear molecular geometry describes the geometry around a central atom bonded to two other atoms (or ligands) placed at a bond angle of 180°. Linear organic molecules, such as acetylene (), are often described by invoking sp orbital hybridization for their carbon centers.
According to the VSEPR model (Valence Shel... | Physical sciences | Bond structure | Chemistry |
15296960 | https://en.wikipedia.org/wiki/Bent%20molecular%20geometry | Bent molecular geometry | In chemistry, molecules with a non-collinear arrangement of two adjacent bonds have bent molecular geometry, also known as angular or V-shaped. Certain atoms, such as oxygen, will almost always set their two (or more) covalent bonds in non-collinear directions due to their electron configuration. Water (H2O) is an exam... | Physical sciences | Bond structure | Chemistry |
10152440 | https://en.wikipedia.org/wiki/Dallasaurus | Dallasaurus | Dallasaurus ("Dallas lizard") is a basal mosasauroid from the Upper Cretaceous of North America. Along with Russellosaurus, Dallasaurus is one of the two oldest mosasauroid taxa currently known from North America. It is also one of the smallest known mosasaurines, measuring approximately in length.
Specimens
The gen... | Biology and health sciences | Prehistoric squamates | Animals |
10153680 | https://en.wikipedia.org/wiki/Fluoxetine | Fluoxetine | Fluoxetine, sold under the brand name Prozac, among others, is an antidepressant medication of the selective serotonin reuptake inhibitor (SSRI) class used for the treatment of major depressive disorder, anxiety, obsessive–compulsive disorder (OCD), panic disorder, premenstrual dysphoric disorder, and bulimia nervosa. ... | Biology and health sciences | Psychiatric drugs | Health |
222676 | https://en.wikipedia.org/wiki/Lewis%20acids%20and%20bases | Lewis acids and bases | A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any species that has a filled orbital containing an electron pair which is not invo... | Physical sciences | Concepts | Chemistry |
222881 | https://en.wikipedia.org/wiki/Pint | Pint | The pint (, ; symbol pt, sometimes abbreviated as p) is a unit of volume or capacity in both the imperial and United States customary measurement systems. In both of those systems it is traditionally one eighth of a gallon. The British imperial pint is about 20% larger than the American pint because the two systems are... | Physical sciences | Volume | Basics and measurement |
223033 | https://en.wikipedia.org/wiki/Gannet | Gannet | Gannets are seabirds comprising the genus Morus in the family Sulidae, closely related to boobies. They are known as 'solan' or 'solan goose' in Scotland. A common misconception is that the Scottish name is 'guga' but this is the Gaelic name referring to the chicks only.
Gannets are large white birds with yellowish he... | Biology and health sciences | Pelecanimorphae | Animals |
223034 | https://en.wikipedia.org/wiki/Booby | Booby | A booby is a seabird in the genus Sula, part of the family Sulidae. Boobies are closely related to the gannets (Morus), which were formerly included in Sula.
Systematics and evolution
The genus Sula was introduced by the French zoologist Mathurin Jacques Brisson in 1760. The type species is the brown booby. The name... | Biology and health sciences | Pelecanimorphae | Animals |
223204 | https://en.wikipedia.org/wiki/Emperor%20penguin | Emperor penguin | The emperor penguin (Aptenodytes forsteri) is the tallest and heaviest of all living penguin species and is endemic to Antarctica. The male and female are similar in plumage and size, reaching in length and weighing from . Feathers of the head and back are black and sharply delineated from the white belly, pale-yellow... | Biology and health sciences | Sphenisciformes | Animals |
223325 | https://en.wikipedia.org/wiki/Software%20design | Software design | Software design is the process of conceptualizing how a software system will work before it is implemented or modified.
Software design also refers to the direct result of the design process the concepts of how the software will work which consists of both design documentation and undocumented concepts.
Software desi... | Technology | Software development: General | null |
223356 | https://en.wikipedia.org/wiki/Power%20inverter | Power inverter | A power inverter, inverter, or invertor is a power electronic device or circuitry that changes direct current (DC) to alternating current (AC). The resulting AC frequency obtained depends on the particular device employed. Inverters do the opposite of rectifiers which were originally large electromechanical devices con... | Technology | Functional circuits | null |
223396 | https://en.wikipedia.org/wiki/Laridae | Laridae | Laridae is a family of seabirds in the order Charadriiformes that includes the gulls, terns (including white terns), noddies, and skimmers. It includes around 100 species arranged into 22 genera. They are an adaptable group of mostly aerial birds found worldwide.
Taxonomy
The family Laridae was introduced (as Laridia... | Biology and health sciences | Charadriiformes | Animals |
223397 | https://en.wikipedia.org/wiki/Larus | Larus | Larus is a large genus of gulls with worldwide distribution (by far the greatest species diversity is in the Northern Hemisphere).
Many of its species are abundant and well-known birds in their ranges. Until about 2005–2007, most gulls were placed in this genus, but this arrangement is now known to be polyphyletic, le... | Biology and health sciences | Charadriiformes | Animals |
223405 | https://en.wikipedia.org/wiki/Coraciidae | Coraciidae | Coraciidae () is a family of Old World birds, which are known as rollers because of the aerial acrobatics some of these birds perform during courtship or territorial flights. The family contains 13 species and is divided into two genera. Rollers resemble crows in size and build, and share the colourful appearance of ki... | Biology and health sciences | Piciformes | Animals |
223508 | https://en.wikipedia.org/wiki/Beehive | Beehive | A beehive is an enclosed structure where some honey bee species of the subgenus Apis live and raise their young. Though the word beehive is used to describe the nest of any bee colony, scientific and professional literature distinguishes nest from hive. Nest is used to discuss colonies that house themselves in natural ... | Biology and health sciences | Shelters and structures | Animals |
223515 | https://en.wikipedia.org/wiki/Jersey%20cattle | Jersey cattle | The Jersey is a British breed of small dairy cattle from Jersey, in the British Channel Islands. It is one of three Channel Island cattle breeds, the others being the Alderney – now extinct – and the Guernsey. The milk is high in butterfat and has a characteristic yellowish tinge.
The Jersey adapts well to various cli... | Biology and health sciences | Cattle | Animals |
223980 | https://en.wikipedia.org/wiki/Ice%20crystal | Ice crystal | Ice crystals are solid ice in symmetrical shapes including hexagonal columns, hexagonal plates, and dendritic crystals. Ice crystals are responsible for various atmospheric optic displays and cloud formations.
Formation
At ambient temperature and pressure, water molecules have a V shape. The two hydrogen atoms bond... | Physical sciences | Water | Chemistry |
223986 | https://en.wikipedia.org/wiki/Cycloalkane | Cycloalkane | In organic chemistry, the cycloalkanes (also called naphthenes, but distinct from naphthalene) are the monocyclic saturated hydrocarbons. In other words, a cycloalkane consists only of hydrogen and carbon atoms arranged in a structure containing a single ring (possibly with side chains), and all of the carbon-carbon bo... | Physical sciences | Aliphatic hydrocarbons | Chemistry |
223992 | https://en.wikipedia.org/wiki/Wind%20shear | Wind shear | Wind shear (; also written windshear), sometimes referred to as wind gradient, is a difference in wind speed and/or direction over a relatively short distance in the atmosphere. Atmospheric wind shear is normally described as either vertical or horizontal wind shear. Vertical wind shear is a change in wind speed or dir... | Physical sciences | Winds | Earth science |
224145 | https://en.wikipedia.org/wiki/Northern%20storm%20petrel | Northern storm petrel | Northern storm petrels are seabirds in the genus Hydrobates in the family Hydrobatidae, part of the order Procellariiformes. The family was once lumped with the similar austral storm petrels in the combined storm petrels, but have been split, as they were not closely related. These smallest of seabirds feed on plankton... | Biology and health sciences | Procellariiformes | Animals |
224301 | https://en.wikipedia.org/wiki/Boundary%20layer | Boundary layer | In physics and fluid mechanics, a boundary layer is the thin layer of fluid in the immediate vicinity of a bounding surface formed by the fluid flowing along the surface. The fluid's interaction with the wall induces a no-slip boundary condition (zero velocity at the wall). The flow velocity then monotonically increa... | Physical sciences | Fluid mechanics | Physics |
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