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1027433 | https://en.wikipedia.org/wiki/Wiwaxia | Wiwaxia | Wiwaxia is a genus of soft-bodied animals that were covered in carbonaceous scales and spines that protected it from predators. Wiwaxia fossils—mainly isolated scales, but sometimes complete, articulated fossils—are known from early Cambrian and middle Cambrian fossil deposits across the globe. The living animal would ... | Biology and health sciences | Mollusks | Animals |
1028100 | https://en.wikipedia.org/wiki/Sit-up | Sit-up | The sit-up is an abdominal endurance training exercise to strengthen, tighten and tone the abdominal muscles. It is similar to a curl-up (that target the rectus abdominis and also work the external and internal obliques), but sit-ups have a fuller range of motion and condition additional muscles.
Form
Sit-ups begin wi... | Biology and health sciences | Physical fitness | Health |
1028265 | https://en.wikipedia.org/wiki/Asterism%20%28astronomy%29 | Asterism (astronomy) | An asterism is an observed pattern or group of stars in the sky. Asterisms can be any identified pattern or group of stars, and therefore are a more general concept than the 88 formally defined constellations. Constellations are based on asterisms, but unlike asterisms, constellations outline and today completely divid... | Physical sciences | Celestial sphere: General | Astronomy |
1028552 | https://en.wikipedia.org/wiki/Nelumbo | Nelumbo | Nelumbo is a genus of aquatic plants with large, showy flowers. Members are commonly called lotus, though the name is also applied to various other plants and plant groups, including the unrelated genus Lotus. Members outwardly resemble those in the family Nymphaeaceae ("water lilies"), but Nelumbo is actually very d... | Biology and health sciences | Others | null |
1028614 | https://en.wikipedia.org/wiki/Nelumbo%20nucifera | Nelumbo nucifera | Nelumbo nucifera, also known as sacred lotus, Indian lotus, or simply lotus, is one of two extant species of aquatic plant in the family Nelumbonaceae. It is sometimes colloquially called a water lily, though this more often refers to members of the family Nymphaeaceae.
Lotus plants are adapted to grow in the flood pl... | Biology and health sciences | Proteales | Plants |
1029022 | https://en.wikipedia.org/wiki/Embryonic%20stem%20cell | Embryonic stem cell | Embryonic stem cells (ESCs) are pluripotent stem cells derived from the inner cell mass of a blastocyst, an early-stage pre-implantation embryo. Human embryos reach the blastocyst stage 4–5 days post fertilization, at which time they consist of 50–150 cells. Isolating the inner cell mass (embryoblast) using immunosurge... | Biology and health sciences | Cell processes | Biology |
1029211 | https://en.wikipedia.org/wiki/Metabolomics | Metabolomics | Metabolomics is the scientific study of chemical processes involving metabolites, the small molecule substrates, intermediates, and products of cell metabolism. Specifically, metabolomics is the "systematic study of the unique chemical fingerprints that specific cellular processes leave behind", the study of their smal... | Biology and health sciences | Metabolic processes | Biology |
1029967 | https://en.wikipedia.org/wiki/Hypernucleus | Hypernucleus | A hypernucleus is similar to a conventional atomic nucleus, but contains at least one hyperon in addition to the normal protons and neutrons. Hyperons are a category of baryon particles that carry non-zero strangeness quantum number, which is conserved by the strong and electromagnetic interactions.
A variety of react... | Physical sciences | Nuclear physics | Physics |
344536 | https://en.wikipedia.org/wiki/Hepatitis%20A | Hepatitis A | Hepatitis A is an infectious disease of the liver caused by Hepatovirus A (HAV); it is a type of viral hepatitis. Many cases have few or no symptoms, especially in the young. The time between infection and symptoms, in those who develop them, is two–six weeks. When symptoms occur, they typically last eight weeks and ma... | Biology and health sciences | Viral diseases | Health |
344618 | https://en.wikipedia.org/wiki/China%20National%20Space%20Administration | China National Space Administration | The China National Space Administration (CNSA) is a government agency of the People's Republic of China headquartered in Haidian, Beijing, responsible for civil space administration and international space cooperation. These responsibilities include organizing or leading foreign exchanges and cooperation in the aerospa... | Technology | Programs and launch sites | null |
344673 | https://en.wikipedia.org/wiki/Apocynaceae | Apocynaceae | Apocynaceae (, from Apocynum, Greek for "dog-away") is a family of flowering plants that includes trees, shrubs, herbs, stem succulents, and vines, commonly known as the dogbane family, because some taxa were used as dog poison. Members of the family are native to the European, Asian, African, Australian, and American ... | Biology and health sciences | Others | null |
344775 | https://en.wikipedia.org/wiki/Earthenware | Earthenware | Earthenware is glazed or unglazed nonvitreous pottery that has normally been fired below . Basic earthenware, often called terracotta, absorbs liquids such as water. However, earthenware can be made impervious to liquids by coating it with a ceramic glaze, and such a process is used for the great majority of modern d... | Technology | Materials | null |
344899 | https://en.wikipedia.org/wiki/Quercus%20suber | Quercus suber | Quercus suber, commonly called the cork oak, is a medium-sized, evergreen oak tree in the section Quercus sect. Cerris. It is the primary source of cork for wine bottle stoppers and other uses, such as cork flooring and as the cores of cricket balls. It is native to southwest Europe and northwest Africa. In the Medit... | Biology and health sciences | Fagales | Plants |
344974 | https://en.wikipedia.org/wiki/Chemosynthesis | Chemosynthesis | In biochemistry, chemosynthesis is the biological conversion of one or more carbon-containing molecules (usually carbon dioxide or methane) and nutrients into organic matter using the oxidation of inorganic compounds (e.g., hydrogen gas, hydrogen sulfide) or ferrous ions as a source of energy, rather than sunlight, as ... | Biology and health sciences | Basics | Biology |
345035 | https://en.wikipedia.org/wiki/Halo%20%28optical%20phenomenon%29 | Halo (optical phenomenon) | A halo () is an optical phenomenon produced by light (typically from the Sun or Moon) interacting with ice crystals suspended in the atmosphere. Halos can have many forms, ranging from colored or white rings to arcs and spots in the sky. Many of these appear near the Sun or Moon, but others occur elsewhere or even in t... | Physical sciences | Atmospheric optics | Earth science |
345286 | https://en.wikipedia.org/wiki/Gel%20permeation%20chromatography | Gel permeation chromatography | Gel permeation chromatography (GPC) is a type of size-exclusion chromatography (SEC), that separates high molecular weight or colloidal analytes on the basis of size or diameter, typically in organic solvents. The technique is often used for the analysis of polymers. As a technique, SEC was first developed in 1955 by L... | Physical sciences | Chromatography | Chemistry |
345330 | https://en.wikipedia.org/wiki/Iridaceae | Iridaceae | Iridaceae () is a family of plants in order Asparagales, taking its name from the irises. It has a nearly global distribution, with 69 accepted genera with a total of c. 2500 species. It includes a number of economically important cultivated plants, such as species of Freesia, Gladiolus, and Crocus, as well as the crop... | Biology and health sciences | Monocots | null |
345356 | https://en.wikipedia.org/wiki/Skate%20%28fish%29 | Skate (fish) | Skates are cartilaginous fish belonging to the family Rajidae in the superorder Batoidea of rays. More than 150 species have been described, in 17 genera. Softnose skates and pygmy skates were previously treated as subfamilies of Rajidae (Arhynchobatinae and Gurgesiellinae), but are now considered as distinct families.... | Biology and health sciences | Batoidea | null |
345366 | https://en.wikipedia.org/wiki/Luna%20moth | Luna moth | The luna moth (Actias luna), also called the American moon moth, is a Nearctic moth in the family Saturniidae, subfamily Saturniinae, a group commonly named the giant silk moths.
The moth has lime-green wings and a white body. Its caterpillars are also green. Its typical wingspan is roughly , but wingspans can exceed ... | Biology and health sciences | Lepidoptera | Animals |
345526 | https://en.wikipedia.org/wiki/DEET | DEET | N,N-Diethyl-meta-toluamide, also called diethyltoluamide or DEET (, from DET, the initials of di- + ethyl + toluamide), is the oldest, one of the most effective, and most common active ingredients in commercial insect repellents. It is a slightly yellow oil intended to be applied to the skin or to clothing and provides... | Physical sciences | Amides and amines | Chemistry |
345938 | https://en.wikipedia.org/wiki/Libellulidae | Libellulidae | The chasers, darters, skimmers, and perchers and their relatives form the Libellulidae, the largest family of dragonflies. It is sometimes considered to contain the Corduliidae as the subfamily Corduliinae and the Macromiidae as the subfamily Macromiinae. Even if these are excluded (as Silsby does), there remains a fam... | Biology and health sciences | Odonata | Animals |
346030 | https://en.wikipedia.org/wiki/Improper%20integral | Improper integral | In mathematical analysis, an improper integral is an extension of the notion of a definite integral to cases that violate the usual assumptions for that kind of integral. In the context of Riemann integrals (or, equivalently, Darboux integrals), this typically involves unboundedness, either of the set over which the in... | Mathematics | Integral calculus | null |
346133 | https://en.wikipedia.org/wiki/Annihilation | Annihilation | In particle physics, annihilation is the process that occurs when a subatomic particle collides with its respective antiparticle to produce other particles, such as an electron colliding with a positron to produce two photons. The total energy and momentum of the initial pair are conserved in the process and distribute... | Physical sciences | Particle physics: General | Physics |
346312 | https://en.wikipedia.org/wiki/Tachinidae | Tachinidae | The Tachinidae are a large and variable family of true flies within the insect order Diptera, with more than 8,200 known species and many more to be discovered. Over 1,300 species have been described in North America alone. Insects in this family commonly are called tachinid flies or simply tachinids. As far as is know... | Biology and health sciences | Flies (Diptera) | Animals |
346315 | https://en.wikipedia.org/wiki/Human%20variability | Human variability | Human variability, or human variation, is the range of possible values for any characteristic, physical or mental, of human beings.
Frequently debated areas of variability include cognitive ability, personality, physical appearance (body shape, skin color, etc.) and immunology.
Variability is partly heritable and par... | Biology and health sciences | Human anatomy | Health |
346451 | https://en.wikipedia.org/wiki/Abrasive | Abrasive | An abrasive is a material, often a mineral, that is used to shape or finish a workpiece through rubbing which leads to part of the workpiece being worn away by friction. While finishing a material often means polishing it to gain a smooth, reflective surface, the process can also involve roughening as in satin, matte o... | Technology | Material and chemical | null |
346547 | https://en.wikipedia.org/wiki/Reusability | Reusability | In computer science and software engineering, reusability is the use of existing assets in some form within the software product development process; these assets are products and by-products of the software development life cycle and include code, software components, test suites, designs and documentation. The opposi... | Technology | Software development: General | null |
346860 | https://en.wikipedia.org/wiki/Ajwain | Ajwain | Ajwain or ajowan (Trachyspermum ammi) () —also known as ajowancaraway,
thymol seeds, bishop's weed, or carom—is an annual herb in the family Apiaceae. Both the leaves and the seed‑like fruit (often mistakenly called seeds) of the plant are consumed by humans. The name "bishop's weed" also is a common name for other p... | Biology and health sciences | Herbs and spices | Plants |
346865 | https://en.wikipedia.org/wiki/Basil | Basil | Basil (, ; , ; Ocimum basilicum (, )), also called great basil, is a culinary herb of the family Lamiaceae (mints). It is a tender plant, and is used in cuisines worldwide. In Western cuisine, the generic term "basil" refers to the variety also known as Genovese basil or sweet basil. Basil is native to tropical regions... | Biology and health sciences | Lamiales | null |
346892 | https://en.wikipedia.org/wiki/Tendril | Tendril | In botany, a tendril is a specialized stem, leaf or petiole with a thread-like shape used by climbing plants for support and attachment, as well as cellular invasion by parasitic plants such as Cuscuta. There are many plants that have tendrils; including sweet peas, passionflower, grapes and the Chilean glory-flower. T... | Biology and health sciences | Plant anatomy and morphology: General | Biology |
346896 | https://en.wikipedia.org/wiki/Berkeley%20Open%20Infrastructure%20for%20Network%20Computing | Berkeley Open Infrastructure for Network Computing | The Berkeley Open Infrastructure for Network Computing (BOINC, pronounced – rhymes with "oink") is an open-source middleware system for volunteer computing (a type of distributed computing). Developed originally to support SETI@home, it became the platform for many other applications in areas as diverse as medicine, ... | Technology | Science | null |
346939 | https://en.wikipedia.org/wiki/Carob | Carob | The carob ( ; Ceratonia siliqua) is a flowering evergreen tree or shrub in the Caesalpinioideae sub-family of the legume family, Fabaceae. It is widely cultivated for its edible fruit, which takes the form of seed pods, and as an ornamental tree in gardens and landscapes. The carob tree is native to the Mediterranean r... | Biology and health sciences | Other culinary fruits | Plants |
347123 | https://en.wikipedia.org/wiki/Lymph | Lymph | Lymph () is the fluid that flows through the lymphatic system, a system composed of lymph vessels (channels) and intervening lymph nodes whose function, like the venous system, is to return fluid from the tissues to be recirculated. At the origin of the fluid-return process, interstitial fluid—the fluid between the cel... | Biology and health sciences | Circulatory system | Biology |
347603 | https://en.wikipedia.org/wiki/Carpenter%20bee | Carpenter bee | Carpenter bees are species in the genus Xylocopa of the subfamily Xylocopinae. The genus includes some 500 bees in 31 subgenera. The common name "carpenter bee" derives from their nesting behavior; nearly all species burrow into hard plant material such as dead wood or bamboo. The main exceptions are species in the sub... | Biology and health sciences | Hymenoptera | Animals |
347838 | https://en.wikipedia.org/wiki/Nuclear%20medicine | Nuclear medicine | Nuclear medicine (nuclear radiology, nucleology), is a medical specialty involving the application of radioactive substances in the diagnosis and treatment of disease. Nuclear imaging is, in a sense, radiology done inside out, because it records radiation emitted from within the body rather than radiation that is trans... | Biology and health sciences | Fields of medicine | Health |
14664934 | https://en.wikipedia.org/wiki/Glock | Glock | Glock (; stylized as GLOCK) is a brand of polymer-framed, short-recoil-operated, striker-fired, locked-breech semi-automatic pistols designed and produced by Austrian manufacturer Glock Ges.m.b.H.
The firearm entered Austrian military and police service in 1982 after becoming the top performer in reliability and safet... | Technology | Specific firearms | null |
3084010 | https://en.wikipedia.org/wiki/Gatehouse | Gatehouse | A gatehouse is a type of fortified gateway, an entry control point building, enclosing or accompanying a gateway for a town, religious house, castle, manor house, or other fortification building of importance. Gatehouses are typically the most heavily armed section of a fortification, to compensate for being structural... | Technology | Fortification | null |
3086453 | https://en.wikipedia.org/wiki/Core%20sample | Core sample | A core sample is a cylindrical section of (usually) a naturally-occurring substance. Most core samples are obtained by drilling with special drills into the substance, such as sediment or rock, with a hollow steel tube, called a core drill. The hole made for the core sample is called the "core hole". A variety of core ... | Physical sciences | Geology: General | Earth science |
3087602 | https://en.wikipedia.org/wiki/Topological%20order | Topological order | In physics, topological order is a kind of order in the zero-temperature phase of matter (also known as quantum matter). Macroscopically, topological order is defined and described by robust ground state degeneracy and quantized non-abelian geometric phases of degenerate ground states. Microscopically, topological or... | Physical sciences | Quantum mechanics | Physics |
3087674 | https://en.wikipedia.org/wiki/Plymouth%20Rock%20chicken | Plymouth Rock chicken | The Plymouth Rock is an American breed of domestic chicken. It was first seen in Massachusetts in the nineteenth century and for much of the early twentieth century was the most widely kept chicken breed in the United States. It is a dual-purpose bird, raised both for its meat and for its brown eggs. It is resistant to... | Biology and health sciences | Chickens | Animals |
17481271 | https://en.wikipedia.org/wiki/Fluorine | Fluorine | Fluorine is a chemical element; it has symbol F and atomic number 9. It is the lightest halogen and exists at standard conditions as pale yellow diatomic gas. Fluorine is extremely reactive as it reacts with all other elements except for the light inert gases. It is highly toxic.
Among the elements, fluorine ranks 24t... | Physical sciences | Chemical elements_2 | null |
16234880 | https://en.wikipedia.org/wiki/Tree%20frog | Tree frog | A tree frog (or treefrog) is any species of frog that spends a major portion of its lifespan in trees, known as an arboreal state. Several lineages of frogs among the Neobatrachia suborder have given rise to treefrogs, although they are not closely related to each other.
Millions of years of convergent evolution have ... | Biology and health sciences | Frogs and toads | Animals |
16248198 | https://en.wikipedia.org/wiki/Rex%20rabbit | Rex rabbit | The term rex rabbit (without capitalization) refers informally to one of at least eight breeds of domestic rabbit. One such breed is the Rex, which is recognized by the American Rabbit Breeders Association (ARBA) and by the British Rabbit Council (BRC). Other modern-day rex rabbit breeds are listed below. Care must be ... | Biology and health sciences | Rabbits | Animals |
4217326 | https://en.wikipedia.org/wiki/Intracluster%20medium | Intracluster medium | In astronomy, the intracluster medium (ICM) is the superheated plasma that permeates a galaxy cluster. The gas consists mainly of ionized hydrogen and helium and accounts for most of the baryonic material in galaxy clusters. The ICM is heated to temperatures on the order of 10 to 100 megakelvins, emitting strong X-ray ... | Physical sciences | Basics_2 | Astronomy |
11983318 | https://en.wikipedia.org/wiki/Branches%20of%20science | Branches of science | The branches of science, also referred to as sciences, scientific fields or scientific disciplines, are commonly divided into three major groups:
Formal sciences: the study of formal systems, such as those under the branches of logic and mathematics, which use an a priori, as opposed to empirical, methodology. They st... | Physical sciences | Science basics | Basics and measurement |
5617916 | https://en.wikipedia.org/wiki/Propylene%20carbonate | Propylene carbonate | Propylene carbonate (often abbreviated PC) is an organic compound with the formula C4H6O3. It is a cyclic carbonate ester derived from propylene glycol. This colorless and odorless liquid is useful as a polar, aprotic solvent. Propylene carbonate is chiral, but is used as the racemic mixture in most contexts.
Prepara... | Physical sciences | Esters and ethers | Chemistry |
5622659 | https://en.wikipedia.org/wiki/Photometric%20system | Photometric system | In astronomy, a photometric system is a set of well-defined passbands (or optical filters), with a known sensitivity to incident radiation. The sensitivity usually depends on the optical system, detectors and filters used. For each photometric system a set of primary standard stars is provided.
A commonly adopted stan... | Physical sciences | Basics | Astronomy |
5622894 | https://en.wikipedia.org/wiki/Rh%20blood%20group%20system | Rh blood group system | The Rh blood group system is a human blood group system. It contains proteins on the surface of red blood cells. After the ABO blood group system, it is the most likely to be involved in transfusion reactions. The Rh blood group system consisted of 49 defined blood group antigens in 2005. there are over 50 antigens am... | Biology and health sciences | Human anatomy | Health |
11005224 | https://en.wikipedia.org/wiki/Penetrating%20trauma | Penetrating trauma | Penetrating trauma is an open wound injury that occurs when an object pierces the skin and enters a tissue of the body, creating a deep but relatively narrow entry wound. In contrast, a blunt or non-penetrating trauma may have some deep damage, but the overlying skin is not necessarily broken and the wound is still clo... | Biology and health sciences | Types | Health |
11007302 | https://en.wikipedia.org/wiki/Halo%20orbit | Halo orbit | A halo orbit is a periodic, three-dimensional orbit associated with one of the L1, L2 or L3 Lagrange points in the three-body problem of orbital mechanics. Although a Lagrange point is just a point in empty space, its peculiar characteristic is that it can be orbited by a Lissajous orbit or by a halo orbit. These can b... | Physical sciences | Orbital mechanics | Astronomy |
11008314 | https://en.wikipedia.org/wiki/Evolutionary%20history%20of%20plants | Evolutionary history of plants | The evolution of plants has resulted in a wide range of complexity, from the earliest algal mats of unicellular archaeplastids evolved through endosymbiosis, through multicellular marine and freshwater green algae, to spore-bearing terrestrial bryophytes, lycopods and ferns, and eventually to the complex seed-bearing g... | Biology and health sciences | Basics_4 | Biology |
2238936 | https://en.wikipedia.org/wiki/Projection%20screen | Projection screen | A projection screen is an installation consisting of a surface and a support structure used for displaying a projected image for the view of an audience. Projection screens may be permanently installed on a wall, as in a movie theater, mounted to or placed in a ceiling using a rollable projection surface that retracts ... | Technology | Media and communication: Basics | null |
2240066 | https://en.wikipedia.org/wiki/Vertical%20draft | Vertical draft | In meteorology, an updraft (British English: up-draught) is a small-scale current of rising air, often within a cloud.
Overview
Vertical drafts, known as updrafts or downdrafts, are localized regions of warm or cool air that move vertically. A mass of warm air will typically be less dense than the surrounding region, ... | Physical sciences | Winds | Earth science |
2241280 | https://en.wikipedia.org/wiki/Veliidae | Veliidae | Veliidae is a family of gregarious predatory insects in the suborder Heteroptera. They are commonly known as riffle bugs, small water striders, or broad-shouldered water striders because the segment immediately behind the head is wider than the rest of the abdomen. Species of the genus Rhagovelia are also referred to a... | Biology and health sciences | Hemiptera (true bugs) | Animals |
610813 | https://en.wikipedia.org/wiki/Tarnish | Tarnish | Tarnish is a thin layer of corrosion that forms over copper, brass, aluminum, magnesium, neodymium and other similar metals as their outermost layer undergoes a chemical reaction. Tarnish does not always result from the sole effects of oxygen in the air. For example, silver needs hydrogen sulfide to tarnish, although i... | Physical sciences | Redox reactions | Chemistry |
611074 | https://en.wikipedia.org/wiki/Point%20mutation | Point mutation | A point mutation is a genetic mutation where a single nucleotide base is changed, inserted or deleted from a DNA or RNA sequence of an organism's genome. Point mutations have a variety of effects on the downstream protein product—consequences that are moderately predictable based upon the specifics of the mutation. The... | Biology and health sciences | Genetics | Biology |
611177 | https://en.wikipedia.org/wiki/Perchlorate | Perchlorate | A perchlorate is a chemical compound containing the perchlorate ion, , the conjugate base of perchloric acid (ionic perchlorate). As counterions, there can be metal cations, quaternary ammonium cations or other ions, for example, nitronium cation ().
The term perchlorate can also describe perchlorate esters or covalen... | Physical sciences | Halide oxyanions | Chemistry |
611229 | https://en.wikipedia.org/wiki/Dissection | Dissection | Dissection (from Latin "to cut to pieces"; also called anatomization) is the dismembering of the body of a deceased animal or plant to study its anatomical structure. Autopsy is used in pathology and forensic medicine to determine the cause of death in humans. Less extensive dissection of plants and smaller animals pr... | Biology and health sciences | Basics_2 | null |
611249 | https://en.wikipedia.org/wiki/Bell%20tower | Bell tower | A bell tower is a tower that contains one or more bells, or that is designed to hold bells even if it has none. Such a tower commonly serves as part of a Christian church, and will contain church bells, but there are also many secular bell towers, often part of a municipal building, an educational establishment, or a t... | Technology | Mixed-use buildings | null |
611501 | https://en.wikipedia.org/wiki/Coral%20snake | Coral snake | Coral snakes are a large group of elapid snakes that can be divided into two distinct groups, the Old World coral snakes and New World coral snakes. There are 27 species of Old World coral snakes, in three genera (Calliophis, Hemibungarus, and Sinomicrurus), and 83 recognized species of New World coral snakes, in two g... | Biology and health sciences | Reptiles | null |
611537 | https://en.wikipedia.org/wiki/Magnesite | Magnesite | Magnesite is a mineral with the chemical formula (magnesium carbonate). Iron, manganese, cobalt, and nickel may occur as admixtures, but only in small amounts.
Occurrence
Magnesite occurs as veins in and an alteration product of ultramafic rocks, serpentinite and other magnesium rich rock types in both contact and r... | Physical sciences | Minerals | Earth science |
611589 | https://en.wikipedia.org/wiki/Java%20Man | Java Man | Java Man (Homo erectus erectus, formerly also Anthropopithecus erectus or Pithecanthropus erectus) is an early human fossil discovered in 1891 and 1892 on the island of Java (Indonesia). Estimated to be between 700,000 and 1,490,000 years old, it was, at the time of its discovery, the oldest hominid fossil ever found, ... | Biology and health sciences | Homo | Biology |
612029 | https://en.wikipedia.org/wiki/Cyclic%20model | Cyclic model | A cyclic model (or oscillating model) is any of several cosmological models in which the universe follows infinite, or indefinite, self-sustaining cycles. For example, the oscillating universe theory briefly considered by Albert Einstein in 1930 theorized a universe following an eternal series of oscillations, each beg... | Physical sciences | Physical cosmology | Astronomy |
612057 | https://en.wikipedia.org/wiki/Potential%20well | Potential well | A potential well is the region surrounding a local minimum of potential energy. Energy captured in a potential well is unable to convert to another type of energy (kinetic energy in the case of a gravitational potential well) because it is captured in the local minimum of a potential well. Therefore, a body may not pro... | Physical sciences | Classical mechanics | Physics |
612389 | https://en.wikipedia.org/wiki/Akula-class%20submarine | Akula-class submarine | The Akula class, Soviet designation Project 971 Shchuka-B (, NATO reporting name Akula) is a series of fourth generation nuclear-powered attack submarines (SSNs) first deployed by the Soviet Navy in 1986. There are four sub-classes or flights of Shchuka-B, consisting of the original seven Project 971 boats (codenamed A... | Technology | Naval warfare | null |
612479 | https://en.wikipedia.org/wiki/Hydrogen%20line | Hydrogen line | The hydrogen line, 21 centimeter line, or H I line is a spectral line that is created by a change in the energy state of solitary, electrically neutral hydrogen atoms. It is produced by a spin-flip transition, which means the direction of the electron's spin is reversed relative to the spin of the proton. This is a qua... | Physical sciences | Atomic physics | Physics |
613362 | https://en.wikipedia.org/wiki/Solar%20storm | Solar storm | A solar storm is a disturbance on the Sun, which can emanate outward across the heliosphere, affecting the entire Solar System, including Earth and its magnetosphere, and is the cause of space weather in the short-term with long-term patterns comprising space climate.
Types
Solar storms include:
Solar flare, a larg... | Physical sciences | Solar System | Astronomy |
613480 | https://en.wikipedia.org/wiki/Garter%20snake | Garter snake | Garter snake is the common name for small to medium-sized snakes belonging to the genus Thamnophis in the family Colubridae. They are native to North and Central America, ranging from central Canada in the north to Costa Rica in the south.
With about 35 recognized species and subspecies, garter snakes are highly varia... | Biology and health sciences | Reptiles | null |
8841749 | https://en.wikipedia.org/wiki/IPhone | IPhone | The iPhone is a line of smartphones developed and marketed by Apple that run iOS, the company's own mobile operating system. The first-generation iPhone was announced by then–Apple CEO Steve Jobs on January 9, 2007, at Macworld 2007, and launched later that year. Since then, Apple has annually released new iPhone model... | Technology | Computer hardware | null |
1590842 | https://en.wikipedia.org/wiki/Work%20hardening | Work hardening | Work hardening, also known as strain hardening, is the process by which a material's load-bearing capacity (strength) increases during plastic (permanent) deformation. This characteristic is what sets ductile materials apart from brittle materials. Work hardening may be desirable, undesirable, or inconsequential, depen... | Technology | Metallurgy | null |
1590884 | https://en.wikipedia.org/wiki/Chinese%20garden | Chinese garden | The Chinese garden is a landscape garden style which has evolved over three thousand years. It includes both the vast gardens of the Chinese emperors and members of the imperial family, built for pleasure and to impress, and the more intimate gardens created by scholars, poets, former government officials, soldiers and... | Technology | Buildings and infrastructure | null |
1590904 | https://en.wikipedia.org/wiki/Precipitation%20hardening | Precipitation hardening | Precipitation hardening, also called age hardening or particle hardening, is a heat treatment technique used to increase the yield strength of malleable materials, including most structural alloys of aluminium, magnesium, nickel, titanium, and some steels, stainless steels, and duplex stainless steel. In superalloys, i... | Technology | Metallurgy | null |
1591064 | https://en.wikipedia.org/wiki/Breathalyzer | Breathalyzer | A breathalyzer or breathalyser (a portmanteau of breath and analyzer/analyser), also called an alcohol meter, is a device for measuring breath alcohol content (BrAC). It is commonly utilized by law enforcement officers whenever they initiate traffic stops. The name is a genericized trademark of the Breathalyzer brand n... | Technology | Law enforcement equipment | null |
1592048 | https://en.wikipedia.org/wiki/Volcanic%20island | Volcanic island | Geologically, a volcanic island is an island of volcanic origin. The term high island can be used to distinguish such islands from low islands, which are formed from sedimentation or the uplifting of coral reefs (which have often formed on sunken volcanoes).
Definition and origin
There are a number of volcanic islands... | Physical sciences | Oceanic and coastal landforms | Earth science |
1594239 | https://en.wikipedia.org/wiki/Addition%20principle | Addition principle | In combinatorics, the addition principle or rule of sum is a basic counting principle. Stated simply, it is the intuitive idea that if we have A number of ways of doing something and B number of ways of doing another thing and we can not do both at the same time, then there are ways to choose one of the actions. In m... | Mathematics | Combinatorics | null |
1594286 | https://en.wikipedia.org/wiki/Rule%20of%20product | Rule of product | In combinatorics, the rule of product or multiplication principle is a basic counting principle (a.k.a. the fundamental principle of counting). Stated simply, it is the intuitive idea that if there are ways of doing something and ways of doing another thing, then there are ways of performing both actions.
Examples... | Mathematics | Combinatorics | null |
1594759 | https://en.wikipedia.org/wiki/Leaf%20vegetable | Leaf vegetable | Leaf vegetables, also called leafy greens, pot herbs, vegetable greens, or simply greens, are plant leaves eaten as a vegetable, sometimes accompanied by tender petioles and shoots. Leaf vegetables eaten raw in a salad can be called salad greens.
Nearly one thousand species of plants with edible leaves are known. Leaf... | Biology and health sciences | Leafy vegetables | Plants |
1595197 | https://en.wikipedia.org/wiki/Sciadopitys | Sciadopitys | Sciadopitys, commonly called umbrella pines, is a genus of a unique conifers now endemic to Japan. The sole living member of the family Sciadopityaceae is Sciadopitys verticillata, a living fossil. The oldest fossils of Sciadopitys are from the Late Cretaceous of Japan, and the genus was widespread in Laurasia during m... | Biology and health sciences | Pinophyta (Conifers) | Plants |
171865 | https://en.wikipedia.org/wiki/Agricultural%20policy | Agricultural policy | Agricultural policy describes a set of laws relating to domestic agriculture and imports of foreign agricultural products. Governments usually implement agricultural policies with the goal of achieving a specific outcome in the domestic agricultural product markets. Well designed agricultural policies use predetermined... | Technology | Academic disciplines | null |
171879 | https://en.wikipedia.org/wiki/Brachistochrone%20curve | Brachistochrone curve | In physics and mathematics, a brachistochrone curve (), or curve of fastest descent, is the one lying on the plane between a point A and a lower point B, where B is not directly below A, on which a bead slides frictionlessly under the influence of a uniform gravitational field to a given end point in the shortest time.... | Mathematics | Two-dimensional space | null |
171882 | https://en.wikipedia.org/wiki/Calculus%20of%20variations | Calculus of variations | The calculus of variations (or variational calculus) is a field of mathematical analysis that uses variations, which are small changes in functions
and functionals, to find maxima and minima of functionals: mappings from a set of functions to the real numbers. Functionals are often expressed as definite integrals invol... | Mathematics | Calculus and analysis | null |
171885 | https://en.wikipedia.org/wiki/Family%20farm | Family farm | A family farm is generally understood to be a farm owned and/or operated by a family. It is sometimes considered to be an estate passed down by inheritance.
Although a recurring conceptual and archetypal distinction is that of a family farm as a smallholding versus corporate farming as large-scale agribusiness, that n... | Technology | Agriculture, labor and economy | null |
171899 | https://en.wikipedia.org/wiki/Agathis%20australis | Agathis australis | Agathis australis, or kauri, is a coniferous tree in the family Araucariaceae, found north of 38°S in the northern regions of New Zealand's North Island.
It is the largest (by volume) but not tallest species of tree in New Zealand, standing up to 50 m tall in the emergent layer above the forest's main canopy. The tree... | Biology and health sciences | Pinophyta (Conifers) | Plants |
171950 | https://en.wikipedia.org/wiki/Root%20of%20unity | Root of unity | In mathematics, a root of unity, occasionally called a de Moivre number, is any complex number that yields 1 when raised to some positive integer power . Roots of unity are used in many branches of mathematics, and are especially important in number theory, the theory of group characters, and the discrete Fourier trans... | Mathematics | Complex analysis | null |
172081 | https://en.wikipedia.org/wiki/Gooseberry | Gooseberry | Gooseberry ( or (American and northern British) or (southern British)) is a common name for many species of Ribes (which also includes currants), as well as a large number of plants of similar appearance, and also several unrelated plants (see List of gooseberries). The berries of those in the genus Ribes (sometim... | Biology and health sciences | Berries | Plants |
172111 | https://en.wikipedia.org/wiki/Washing%20machine | Washing machine | A washing machine (laundry machine, clothes washer, washer, or simply wash) is a machine designed to launder clothing. The term is mostly applied to machines that use water. Other ways of doing laundry include dry cleaning (which uses alternative cleaning fluids and is performed by specialist businesses) and ultrasonic... | Technology | Household appliances | null |
172121 | https://en.wikipedia.org/wiki/Phonograph%20record | Phonograph record | A phonograph record (also known as a gramophone record, especially in British English) or a vinyl record (for later varieties only) is an analog sound storage medium in the form of a flat disc with an inscribed, modulated spiral groove. The groove usually starts near the outside edge and ends near the center of the dis... | Technology | Media and communication: Basics | null |
172161 | https://en.wikipedia.org/wiki/Blackcurrant | Blackcurrant | The blackcurrant (Ribes nigrum), also known as black currant or cassis, is a deciduous shrub in the family Grossulariaceae grown for its edible berries. It is native to temperate parts of central and northern Europe and northern Asia, where it prefers damp fertile soils. It is widely cultivated both commercially and do... | Biology and health sciences | Others | null |
172174 | https://en.wikipedia.org/wiki/R%C3%A9seau%20Express%20R%C3%A9gional | Réseau Express Régional | The Réseau Express Régional (; ), commonly abbreviated RER (), is a hybrid commuter rail and rapid transit system, similar to the S-Bahns of German-speaking countries and the S Lines of Milan, serving Paris and its suburbs. It acts as a combined city-center underground rail system and suburbs-to-city-center commuter ra... | Technology | France | null |
172273 | https://en.wikipedia.org/wiki/Tick | Tick | Ticks are parasitic arachnids of the order Ixodida. They are part of the mite superorder Parasitiformes. Adult ticks are approximately 3 to 5 mm in length depending on age, sex, species, and "fullness". Ticks are external parasites, living by feeding on the blood of mammals, birds, and sometimes reptiles and amphibians... | Biology and health sciences | Arachnids | null |
172274 | https://en.wikipedia.org/wiki/Centaur%20%28small%20Solar%20System%20body%29 | Centaur (small Solar System body) | In planetary astronomy, a centaur is a small Solar System body that orbits the Sun between Jupiter and Neptune and crosses the orbits of one or more of the giant planets. Centaurs generally have unstable orbits because of this; almost all their orbits have dynamic lifetimes of only a few million years, but there is one... | Physical sciences | Planetary science | Astronomy |
172321 | https://en.wikipedia.org/wiki/Hand%2C%20foot%2C%20and%20mouth%20disease | Hand, foot, and mouth disease | Hand, foot, and mouth disease (HFMD) is a common infection caused by a group of enteroviruses. It typically begins with a fever and feeling generally unwell. This is followed a day or two later by flat discolored spots or bumps that may blister, on the hands, feet and mouth and occasionally buttocks and groin. Signs an... | Biology and health sciences | Infectious disease | null |
172323 | https://en.wikipedia.org/wiki/Rubella | Rubella | Rubella, also known as German measles or three-day measles, is an infection caused by the rubella virus. This disease is often mild, with half of people not realizing that they are infected. A rash may start around two weeks after exposure and last for three days. It usually starts on the face and spreads to the rest o... | Biology and health sciences | Viral diseases | Health |
172333 | https://en.wikipedia.org/wiki/Dispersion%20%28optics%29 | Dispersion (optics) | Dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency. Sometimes the term chromatic dispersion is used to refer to optics specifically, as opposed to wave propagation in general. A medium having this common property may be termed a dispersive medium.
Although the term is used in ... | Physical sciences | Optics | Physics |
172396 | https://en.wikipedia.org/wiki/Lichen | Lichen | A lichen ( , ) is a hybrid colony of algae or cyanobacteria living symbiotically among filaments of multiple fungi species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualistic relationship. Lichens are the lifeform that first brought the term symbiosis (as Symbiotismus) under biological c... | Biology and health sciences | Other organisms | null |
172474 | https://en.wikipedia.org/wiki/Lactic%20acid | Lactic acid | Lactic acid is an organic acid. It has the molecular formula C3H6O3. It is white in the solid state and it is miscible with water. When in the dissolved state, it forms a colorless solution. Production includes both artificial synthesis as well as natural sources. Lactic acid is an alpha-hydroxy acid (AHA) due to the p... | Physical sciences | Carbon–oxygen bond | null |
172592 | https://en.wikipedia.org/wiki/Organic%20reaction | Organic reaction | Organic reactions are chemical reactions involving organic compounds. The basic organic chemistry reaction types are addition reactions, elimination reactions, substitution reactions, pericyclic reactions, rearrangement reactions, photochemical reactions and redox reactions. In organic synthesis, organic reactions are ... | Physical sciences | Organic reactions | Chemistry |
172599 | https://en.wikipedia.org/wiki/Search%20and%20rescue | Search and rescue | Search and rescue (SAR) is the search for and provision of aid to people who are in distress or imminent danger. The general field of search and rescue includes many specialty sub-fields, typically determined by the type of terrain the search is conducted over. These include mountain rescue; ground search and rescue, i... | Biology and health sciences | General concepts | Health |
172644 | https://en.wikipedia.org/wiki/Handedness | Handedness | In human biology, handedness is an individual's preferential use of one hand, known as the dominant hand, due to it being stronger, faster or more dextrous. The other hand, comparatively often the weaker, less dextrous or simply less subjectively preferred, is called the non-dominant hand. In a study from 1975 on 7,688... | Biology and health sciences | Human anatomy | Health |
172716 | https://en.wikipedia.org/wiki/Caltrop | Caltrop | A caltrop (also known as caltrap, galtrop, cheval trap, galthrap, galtrap, calthrop, jackrock or crow's foot) is an area denial weapon made up of usually four, but possibly more, sharp nails or spines arranged in such a manner that one of them always points upward from a stable base (for example, a tetrahedron). Histor... | Technology | Maneuver | null |
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