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Sandfly or sand fly is a colloquial name for any species or genus of flying, biting, blood-sucking dipteran (fly) encountered in sandy areas. In the United States, sandfly may refer to certain horse flies that are also known as "greenheads" (family Tabanidae), or to members of the family Ceratopogonidae. The bites usua... | Sandfly | Wikipedia | 503 | 1471115 | https://en.wikipedia.org/wiki/Sandfly | Biology and health sciences | Flies (Diptera) | Animals |
Leishmania donovani causes spiking fevers, hepatosplenomegaly, and pancytopenia. It can be diagnosed through microscopic review by visualizing amastigotes in containing macrophages, and is treatable with sodium stibogluconate.
Bacteria
Bartonella bacilliformis, the causal agent of Carrion's disease, is transmitted by... | Sandfly | Wikipedia | 364 | 1471115 | https://en.wikipedia.org/wiki/Sandfly | Biology and health sciences | Flies (Diptera) | Animals |
A crutch is a mobility aid that transfers weight from the legs to the upper body. It is often used by people who cannot use their legs to support their weight, for reasons ranging from short-term injuries to lifelong disabilities.
History
Crutches were used in ancient Egypt. In 1917, Emile Schlick patented the first c... | Crutch | Wikipedia | 433 | 1471182 | https://en.wikipedia.org/wiki/Crutch | Technology | Mobility aids | null |
A forearm crutch (also commonly known as an elbow crutch, Canadian crutch or "Lofstrand" crutch due to a brand by this name) has a cuff at the top that goes around the forearm. It is used by inserting the arm into the cuff and holding the grip. The hinged cuff, most frequently made of plastic or metal, can be a half-ci... | Crutch | Wikipedia | 466 | 1471182 | https://en.wikipedia.org/wiki/Crutch | Technology | Mobility aids | null |
Four-point gait
Those who can tolerate partial weight bearing on both legs usually use the four point gait. The sequence is right crutch, left leg, left crutch, right leg. This is the slowest of all gaits but also the safest in that three of the four points are in contact with the ground at any given time.
Two-point g... | Crutch | Wikipedia | 384 | 1471182 | https://en.wikipedia.org/wiki/Crutch | Technology | Mobility aids | null |
The blood orange is a variety of orange with crimson, near blood-colored flesh. It is one of the sweet orange varieties (Citrus × sinensis). It is also known as the raspberry orange.
The dark flesh color is due to the presence of anthocyanins, a family of polyphenol pigments common to many flowers and fruit, but uncom... | Blood orange | Wikipedia | 461 | 1471836 | https://en.wikipedia.org/wiki/Blood%20orange | Biology and health sciences | Citrus fruits | Plants |
The Moro is the most colorful of the blood oranges, with a deep red flesh and a rind with a bright red blush. The flavor is stronger and the aroma is more intense than a normal orange. This fruit has a distinct, sweet flavor with a hint of raspberry. This orange possesses a more bitter taste than the 'Tarocco' or the '... | Blood orange | Wikipedia | 512 | 1471836 | https://en.wikipedia.org/wiki/Blood%20orange | Biology and health sciences | Citrus fruits | Plants |
Sanguinello
The Sanguinello , also called Sanguinelli in the US (the plural form of its name in Italian), discovered in Spain in 1929, has reddish skin, few seeds, and sweet, tender flesh. 'Sanguinello', the Sicilian late "full-blood" orange, is close in characteristics to the 'Moro'. Where grown in the Northern Hemis... | Blood orange | Wikipedia | 371 | 1471836 | https://en.wikipedia.org/wiki/Blood%20orange | Biology and health sciences | Citrus fruits | Plants |
Pleurotus ostreatus, the oyster mushroom, oyster fungus, hiratake, or pearl oyster mushroom is a common edible mushroom.
It is one of the more commonly sought wild mushrooms, though it can also be cultivated on straw and other media.
Description
The mushroom has a broad, fan or oyster-shaped cap spanning ; natural sp... | Pleurotus ostreatus | Wikipedia | 476 | 1473803 | https://en.wikipedia.org/wiki/Pleurotus%20ostreatus | Biology and health sciences | Edible fungi | null |
Distribution and habitat
The oyster mushroom is widespread in many temperate and subtropical forests throughout the world, although it is absent from the Pacific Northwest of North America, being replaced by P. pulmonarius and P. populinus. It is a saprotroph that acts as a primary decomposer of wood, especially decid... | Pleurotus ostreatus | Wikipedia | 492 | 1473803 | https://en.wikipedia.org/wiki/Pleurotus%20ostreatus | Biology and health sciences | Edible fungi | null |
Oyster mushrooms can also be used industrially for mycoremediation purposes. Oyster mushrooms were used to treat soil that had been polluted with diesel oil. The mushroom was able to convert 95% of the oil into non-toxic compounds. P. ostreatus is also capable of growing upon and degrading oxo-biodegradable plastic bag... | Pleurotus ostreatus | Wikipedia | 87 | 1473803 | https://en.wikipedia.org/wiki/Pleurotus%20ostreatus | Biology and health sciences | Edible fungi | null |
The Compton wavelength is a quantum mechanical property of a particle, defined as the wavelength of a photon whose energy is the same as the rest energy of that particle (see mass–energy equivalence). It was introduced by Arthur Compton in 1923 in his explanation of the scattering of photons by electrons (a process kno... | Compton wavelength | Wikipedia | 458 | 1474467 | https://en.wikipedia.org/wiki/Compton%20wavelength | Physical sciences | Quantum mechanics | Physics |
This limitation depends on the mass of the particle.
To see how, note that we can measure the position of a particle by bouncing light off it – but measuring the position accurately requires light of short wavelength. Light with a short wavelength consists of photons of high energy. If the energy of these photons exce... | Compton wavelength | Wikipedia | 475 | 1474467 | https://en.wikipedia.org/wiki/Compton%20wavelength | Physical sciences | Quantum mechanics | Physics |
The Planck mass is the order of mass for which the Compton wavelength and the Schwarzschild radius are the same, when their value is close to the Planck length (). The Schwarzschild radius is proportional to the mass, whereas the Compton wavelength is proportional to the inverse of the mass. The Planck mass and length... | Compton wavelength | Wikipedia | 124 | 1474467 | https://en.wikipedia.org/wiki/Compton%20wavelength | Physical sciences | Quantum mechanics | Physics |
In developmental biology, animal embryonic development, also known as animal embryogenesis, is the developmental stage of an animal embryo. Embryonic development starts with the fertilization of an egg cell (ovum) by a sperm cell (spermatozoon). Once fertilized, the ovum becomes a single diploid cell known as a zygote.... | Animal embryonic development | Wikipedia | 475 | 1474542 | https://en.wikipedia.org/wiki/Animal%20embryonic%20development | Biology and health sciences | Animal reproduction | Biology |
To prevent more than one sperm fertilizing the egg (polyspermy), fast block and slow block to polyspermy are used. Fast block, the membrane potential rapidly depolarizing and then returning to normal, happens immediately after an egg is fertilized by a single sperm. Slow block begins in the first few seconds after fert... | Animal embryonic development | Wikipedia | 452 | 1474542 | https://en.wikipedia.org/wiki/Animal%20embryonic%20development | Biology and health sciences | Animal reproduction | Biology |
In amniotes, the cells of the morula are at first closely aggregated, but soon they become arranged into an outer or peripheral layer, the trophoblast, which does not contribute to the formation of the embryo proper, and an inner cell mass, from which the embryo is developed. Fluid collects between the trophoblast and ... | Animal embryonic development | Wikipedia | 324 | 1474542 | https://en.wikipedia.org/wiki/Animal%20embryonic%20development | Biology and health sciences | Animal reproduction | Biology |
Before gastrulation, the cells of the trophoblast become differentiated into two layers: The outer layer forms a syncytium (i.e., a layer of protoplasm studded with nuclei, but showing no evidence of subdivision into cells), termed the syncytiotrophoblast, while the inner layer, the cytotrophoblast, consists of well-de... | Animal embryonic development | Wikipedia | 265 | 1474542 | https://en.wikipedia.org/wiki/Animal%20embryonic%20development | Biology and health sciences | Animal reproduction | Biology |
The embryonic disc becomes oval and then pear-shaped, the wider end being directed forward. Towards the narrow, posterior end, an opaque primitive streak, is formed and extends along the middle of the disc for about half of its length; at the anterior end of the streak there is a knob-like thickening termed the primiti... | Animal embryonic development | Wikipedia | 296 | 1474542 | https://en.wikipedia.org/wiki/Animal%20embryonic%20development | Biology and health sciences | Animal reproduction | Biology |
During gastrulation cells migrate to the interior of the blastula, subsequently forming two (in diploblastic animals) or three (triploblastic) germ layers. The embryo during this process is called a gastrula. The germ layers are referred to as the ectoderm, mesoderm and endoderm. In diploblastic animals only the ectode... | Animal embryonic development | Wikipedia | 359 | 1474542 | https://en.wikipedia.org/wiki/Animal%20embryonic%20development | Biology and health sciences | Animal reproduction | Biology |
In front of the primitive streak, two longitudinal ridges, caused by a folding up of the ectoderm, make their appearance, one on either side of the middle line formed by the streak. These are named the neural folds; they commence some little distance behind the anterior end of the embryonic disk, where they are continu... | Animal embryonic development | Wikipedia | 424 | 1474542 | https://en.wikipedia.org/wiki/Animal%20embryonic%20development | Biology and health sciences | Animal reproduction | Biology |
The cephalic end of the neural groove exhibits several dilatations that, when the tube is closed, assume the form of the three primary brain vesicles, and correspond, respectively, to the future forebrain (prosencephalon), midbrain (mesencephalon), and hindbrain (rhombencephalon) (Fig. 18). The walls of the vesicles ar... | Animal embryonic development | Wikipedia | 474 | 1474542 | https://en.wikipedia.org/wiki/Animal%20embryonic%20development | Biology and health sciences | Animal reproduction | Biology |
Somitogenesis is the process by which somites (primitive segments) are produced. These segmented tissue blocks differentiate into skeletal muscle, vertebrae, and dermis of all vertebrates.
Somitogenesis begins with the formation of somitomeres (whorls of concentric mesoderm) marking the future somites in the presomiti... | Animal embryonic development | Wikipedia | 462 | 1474542 | https://en.wikipedia.org/wiki/Animal%20embryonic%20development | Biology and health sciences | Animal reproduction | Biology |
At some point after the different germ layers are defined, organogenesis begins. The first stage in vertebrates is called neurulation, where the neural plate folds forming the neural tube (see above). Other common organs or structures that arise at this time include the heart and somites (also above), but from now on e... | Animal embryonic development | Wikipedia | 130 | 1474542 | https://en.wikipedia.org/wiki/Animal%20embryonic%20development | Biology and health sciences | Animal reproduction | Biology |
An adverse effect is an undesired harmful effect resulting from a medication or other intervention, such as surgery. An adverse effect may be termed a "side effect", when judged to be secondary to a main or therapeutic effect. The term complication is similar to adverse effect, but the latter is typically used in pharm... | Adverse effect | Wikipedia | 494 | 1474961 | https://en.wikipedia.org/wiki/Adverse%20effect | Biology and health sciences | General concepts_2 | Health |
Reporting systems
In many countries, adverse effects are required by law to be reported, researched in clinical trials and included into the patient information accompanying medical devices and drugs for sale to the public. Investigators in human clinical trials are obligated to report these events in clinical study re... | Adverse effect | Wikipedia | 417 | 1474961 | https://en.wikipedia.org/wiki/Adverse%20effect | Biology and health sciences | General concepts_2 | Health |
New Zealand
Adverse reaction reporting is an important component of New Zealand's pharmacovigilance activities. The Centre for Adverse Reactions Monitoring (CARM) in Dunedin is New Zealand's national monitoring centre for adverse reactions. It collects and evaluates spontaneous reports of adverse reactions to medicines... | Adverse effect | Wikipedia | 500 | 1474961 | https://en.wikipedia.org/wiki/Adverse%20effect | Biology and health sciences | General concepts_2 | Health |
Other nonsurgical physical procedures, such as high-intensity radiation therapy, may cause burns and alterations in the skin. In general, these therapies try to avoid damage to healthy tissues while maximizing the therapeutic effect.
Vaccination may have adverse effects due to the nature of its biological preparation,... | Adverse effect | Wikipedia | 512 | 1474961 | https://en.wikipedia.org/wiki/Adverse%20effect | Biology and health sciences | General concepts_2 | Health |
The scientific field of activity associated with drug safety is increasingly government-regulated, and is of major concern for the public, as well as to drug manufacturers. The distinction between adverse and nonadverse effects is a major undertaking when a new drug is developed and tested before marketing it. This is ... | Adverse effect | Wikipedia | 367 | 1474961 | https://en.wikipedia.org/wiki/Adverse%20effect | Biology and health sciences | General concepts_2 | Health |
Examples with specific medications
Abortion, miscarriage or uterine hemorrhage associated with misoprostol (Cytotec), a labor-inducing drug (this is a case where the adverse effect has been used legally and illegally for performing abortions)
Addiction to many sedatives and analgesics, such as diazepam, morphine, etc... | Adverse effect | Wikipedia | 496 | 1474961 | https://en.wikipedia.org/wiki/Adverse%20effect | Biology and health sciences | General concepts_2 | Health |
Tardive dyskinesia associated with use of metoclopramide and many antipsychotic medications | Adverse effect | Wikipedia | 25 | 1474961 | https://en.wikipedia.org/wiki/Adverse%20effect | Biology and health sciences | General concepts_2 | Health |
Controversies
Sometimes, putative medical adverse effects are regarded as controversial and generate heated discussions in society and lawsuits against drug manufacturers. One example is the recent controversy as to whether autism was linked to the MMR vaccine (or to thiomersal, a mercury-based preservative used in som... | Adverse effect | Wikipedia | 263 | 1474961 | https://en.wikipedia.org/wiki/Adverse%20effect | Biology and health sciences | General concepts_2 | Health |
Green beans are young, unripe fruits of various cultivars of the common bean (Phaseolus vulgaris), although immature or young pods of the runner bean (Phaseolus coccineus), yardlong bean (Vigna unguiculata subsp. sesquipedalis), and hyacinth bean (Lablab purpureus) are used in a similar way. Green beans are known by ma... | Green bean | Wikipedia | 488 | 1475860 | https://en.wikipedia.org/wiki/Green%20bean | Biology and health sciences | Fabales | null |
Plant
Green beans are classified by growth habit into two major groups, "bush" (or "dwarf") beans and "pole" (or "climbing") beans.
Bush beans are short plants, growing to not more than in height, often without requiring supports. They generally reach maturity and produce all of their fruit in a relatively short per... | Green bean | Wikipedia | 491 | 1475860 | https://en.wikipedia.org/wiki/Green%20bean | Biology and health sciences | Fabales | null |
Production
In 2020, world production of green beans was 23 million tonnes, with China accounting for 77% of the total (table).
Gallery | Green bean | Wikipedia | 28 | 1475860 | https://en.wikipedia.org/wiki/Green%20bean | Biology and health sciences | Fabales | null |
Tetraethyl pyrophosphate, abbreviated TEPP, is an organophosphate compound with the formula . It is the tetraethyl derivative of pyrophosphate (P2O74-). It is a colorless oil that solidifies near room temperature. It is used as an insecticide. The compound hydrolyzes rapidly.
Applications
TEPP is an insecticide to ap... | Tetraethyl pyrophosphate | Wikipedia | 495 | 33284883 | https://en.wikipedia.org/wiki/Tetraethyl%20pyrophosphate | Technology | Pest and disease control | null |
Death is mostly due to either respiratory failure and in some cases cardiac arrest. The route of absorption might be responsible for the range of effect on certain systems.
For cold-blooded animals the effects are slightly different. In a study with frogs, acute exposure caused a depression in the amount of erythrocyt... | Tetraethyl pyrophosphate | Wikipedia | 482 | 33284883 | https://en.wikipedia.org/wiki/Tetraethyl%20pyrophosphate | Technology | Pest and disease control | null |
Around the beginning of the Second World War, TEPP was discovered to be an inhibitor of cholinesterases. Schrader referred to the studies by Eberhard Gross, who was the first to recognize the mechanism of action for TEPP in 1939. More experiments were conducted including those of Hans Gremels, who confirmed Gross's wor... | Tetraethyl pyrophosphate | Wikipedia | 207 | 33284883 | https://en.wikipedia.org/wiki/Tetraethyl%20pyrophosphate | Technology | Pest and disease control | null |
The gradient theorem, also known as the fundamental theorem of calculus for line integrals, says that a line integral through a gradient field can be evaluated by evaluating the original scalar field at the endpoints of the curve. The theorem is a generalization of the second fundamental theorem of calculus to any curv... | Gradient theorem | Wikipedia | 494 | 5337437 | https://en.wikipedia.org/wiki/Gradient%20theorem | Mathematics | Multivariable and vector calculus | null |
This result can be obtained much more simply by noticing that the function has gradient , so by the Gradient Theorem:
Example 2
For a more abstract example, suppose has endpoints , , with orientation from to . For in , let denote the Euclidean norm of . If is a real number, then
Here the final equality follows... | Gradient theorem | Wikipedia | 476 | 5337437 | https://en.wikipedia.org/wiki/Gradient%20theorem | Mathematics | Multivariable and vector calculus | null |
It is straightforward to show that a vector field is path-independent if and only if the integral of the vector field over every closed loop in its domain is zero. Thus the converse can alternatively be stated as follows: If the integral of over every closed loop in the domain of is zero, then is the gradient of som... | Gradient theorem | Wikipedia | 476 | 5337437 | https://en.wikipedia.org/wiki/Gradient%20theorem | Mathematics | Multivariable and vector calculus | null |
Using the above proof, we know is well-defined and differentiable, and (from this formula we can use the gradient theorem to easily derive the well-known formula for calculating work done by conservative forces: ). This function is often referred to as the electrostatic potential energy of the system of charges in ... | Gradient theorem | Wikipedia | 373 | 5337437 | https://en.wikipedia.org/wiki/Gradient%20theorem | Mathematics | Multivariable and vector calculus | null |
Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthropods including decapods (shrimps, prawns, crabs, lobsters and crayfish), seed shrimp, bra... | Crustacean | Wikipedia | 364 | 40119056 | https://en.wikipedia.org/wiki/Crustacean | Biology and health sciences | Biology | null |
Most crustaceans are free-living aquatic animals, but some are terrestrial (e.g. woodlice, sandhoppers), some are parasitic (e.g. Rhizocephala, fish lice, tongue worms) and some are sessile (e.g. barnacles). The group has an extensive fossil record, reaching back to the Cambrian. More than 7.9 million tons of crustacea... | Crustacean | Wikipedia | 328 | 40119056 | https://en.wikipedia.org/wiki/Crustacean | Biology and health sciences | Biology | null |
Each somite, or body segment can bear a pair of appendages: on the segments of the head, these include two pairs of antennae, the mandibles and maxillae; the thoracic segments bear legs, which may be specialised as pereiopods (walking legs) and maxillipeds (feeding legs). Malacostraca and Remipedia (and the hexapods) h... | Crustacean | Wikipedia | 465 | 40119056 | https://en.wikipedia.org/wiki/Crustacean | Biology and health sciences | Biology | null |
In many decapods, the first (and sometimes the second) pair of pleopods are specialised in the male for sperm transfer. Many terrestrial crustaceans (such as the Christmas Island red crab) mate seasonally and return to the sea to release the eggs. Others, such as woodlice, lay their eggs on land, albeit in damp conditi... | Crustacean | Wikipedia | 377 | 40119056 | https://en.wikipedia.org/wiki/Crustacean | Biology and health sciences | Biology | null |
Mating system
Most crustaceans have separate sexes, and reproduce sexually. In fact, a recent study explains how the male T. californicus decide which females to mate with by dietary differences, preferring when the females are algae-fed instead of yeast-fed. A small number are hermaphrodites, including barnacles, remi... | Crustacean | Wikipedia | 322 | 40119056 | https://en.wikipedia.org/wiki/Crustacean | Biology and health sciences | Biology | null |
Crustaceans exhibit a number of larval forms, of which the earliest and most characteristic is the nauplius. This has three pairs of appendages, all emerging from the young animal's head, and a single naupliar eye. In most groups, there are further larval stages, including the zoea (pl. zoeæ or zoeas). This name was gi... | Crustacean | Wikipedia | 507 | 40119056 | https://en.wikipedia.org/wiki/Crustacean | Biology and health sciences | Biology | null |
The name "crustacean" dates from the earliest works to describe the animals, including those of Pierre Belon and Guillaume Rondelet, but the name was not used by some later authors, including Carl Linnaeus, who included crustaceans among the "Aptera" in his . The earliest nomenclatural valid work to use the name "Crust... | Crustacean | Wikipedia | 308 | 40119056 | https://en.wikipedia.org/wiki/Crustacean | Biology and health sciences | Biology | null |
The traditional classification of Crustacea based on morphology recognised four to six classes.
Bowman and Abele (1982) recognised 652 extant families and 38 orders, organised into six classes: Branchiopoda, Remipedia, Cephalocarida,
Maxillopoda, Ostracoda, and Malacostraca. Martin and Davis (2001) updated this classi... | Crustacean | Wikipedia | 496 | 40119056 | https://en.wikipedia.org/wiki/Crustacean | Biology and health sciences | Biology | null |
Within the Malacostraca, no fossils are known for krill, while both Hoplocarida and Phyllopoda contain important groups that are now extinct as well as extant members (Hoplocarida: mantis shrimp are extant, while Aeschronectida are extinct; Phyllopoda: Canadaspidida are extinct, while Leptostraca are extant). Cumacea a... | Crustacean | Wikipedia | 415 | 40119056 | https://en.wikipedia.org/wiki/Crustacean | Biology and health sciences | Biology | null |
In mathematics, the integral of a non-negative function of a single variable can be regarded, in the simplest case, as the area between the graph of that function and the axis. The Lebesgue integral, named after French mathematician Henri Lebesgue, is one way to make this concept rigorous and to extend it to more gene... | Lebesgue integral | Wikipedia | 481 | 26064288 | https://en.wikipedia.org/wiki/Lebesgue%20integral | Mathematics | Integral calculus | null |
However, Riemann integration does not interact well with taking limits of sequences of functions, making such limiting processes difficult to analyze. This is important, for instance, in the study of Fourier series, Fourier transforms, and other topics. The Lebesgue integral describes better how and when it is possible... | Lebesgue integral | Wikipedia | 500 | 26064288 | https://en.wikipedia.org/wiki/Lebesgue%20integral | Mathematics | Integral calculus | null |
The Lebesgue integral may then be defined by adding up the areas of these horizontal slabs. From this perspective, a key difference with the Riemann integral is that the "slabs" are no longer rectangular (cartesian products of two intervals), but instead are cartesian products of a measurable set with an interval.
Si... | Lebesgue integral | Wikipedia | 510 | 26064288 | https://en.wikipedia.org/wiki/Lebesgue%20integral | Mathematics | Integral calculus | null |
where the integral on the right is an ordinary improper Riemann integral, of a non-negative function (interpreted appropriately as if on a neighborhood of 0).
Most textbooks, however, emphasize the simple functions viewpoint, because it is then more straightforward to prove the basic theorems about the Lebesgue inte... | Lebesgue integral | Wikipedia | 487 | 26064288 | https://en.wikipedia.org/wiki/Lebesgue%20integral | Mathematics | Integral calculus | null |
We can show that this is equivalent to requiring that the pre-image of any Borel subset of be in . The set of measurable functions is closed under algebraic operations, but more importantly it is closed under various kinds of point-wise sequential limits:
are measurable if the original sequence , where , consists of ... | Lebesgue integral | Wikipedia | 473 | 26064288 | https://en.wikipedia.org/wiki/Lebesgue%20integral | Mathematics | Integral calculus | null |
where the coefficients are real numbers and are disjoint measurable sets, is called a measurable simple function. We extend the integral by linearity to non-negative measurable simple functions. When the coefficients are positive, we set
whether this sum is finite or +∞. A simple function can be written in differe... | Lebesgue integral | Wikipedia | 512 | 26064288 | https://en.wikipedia.org/wiki/Lebesgue%20integral | Mathematics | Integral calculus | null |
It turns out that this definition gives the desirable properties of the integral.
Via improper Riemann integral
Assuming that is measurable and non-negative, the function
is monotonically non-increasing. The Lebesgue integral may then be defined as the improper Riemann integral of :
This integral is improper at th... | Lebesgue integral | Wikipedia | 471 | 26064288 | https://en.wikipedia.org/wiki/Lebesgue%20integral | Mathematics | Integral calculus | null |
Limitations of the Riemann integral
With the advent of Fourier series, many analytical problems involving integrals came up whose satisfactory solution required interchanging limit processes and integral signs. However, the conditions under which the integrals
are equal proved quite elusive in the Riemann framework. ... | Lebesgue integral | Wikipedia | 312 | 26064288 | https://en.wikipedia.org/wiki/Lebesgue%20integral | Mathematics | Integral calculus | null |
The following theorems are proved in most textbooks on measure theory and Lebesgue integration.
If and are non-negative measurable functions (possibly assuming the value ) such that almost everywhere, then To wit, the integral respects the equivalence relation of almost-everywhere equality.
If and are functions... | Lebesgue integral | Wikipedia | 424 | 26064288 | https://en.wikipedia.org/wiki/Lebesgue%20integral | Mathematics | Integral calculus | null |
Then is a normed vector space (and in particular, it is a metric space.) All metric spaces have Hausdorff completions, so let be its completion. This space is isomorphic to the space of Lebesgue integrable functions modulo the subspace of functions with integral zero. Furthermore, the Riemann integral is a uniformly... | Lebesgue integral | Wikipedia | 427 | 26064288 | https://en.wikipedia.org/wiki/Lebesgue%20integral | Mathematics | Integral calculus | null |
Chromebook (sometimes stylized in lowercase as chromebook) is a line of laptops, desktops, tablets and all-in-one computers that run ChromeOS, a proprietary operating system developed by Google.
Chromebooks are optimised for web access. They also run Android apps, Linux applications, and Progressive web apps which do... | Chromebook | Wikipedia | 449 | 31747219 | https://en.wikipedia.org/wiki/Chromebook | Technology | Specific hardware | null |
On October 9, 2023, Google announced Chromebook Plus, a new category of Chromebooks that requires minimum hardware specifications, such as CPU (Intel Core i3 12th Gen or the AMD Ryzen 3 7000 series), at least 8 GB of RAM, 128 GB of local storage, 1080p IPS or better display and a 1080p+ web camera. The Plus supports vi... | Chromebook | Wikipedia | 492 | 31747219 | https://en.wikipedia.org/wiki/Chromebook | Technology | Specific hardware | null |
Chromebooks ship with ChromeOS, an operating system that uses the Linux kernel and the Google Chrome web browser with an integrated media-player. Enabling developer mode allows the installation of Linux distributions and other operating systems on Chromebooks. Chromebooks also include a screw or switch directly on the ... | Chromebook | Wikipedia | 503 | 31747219 | https://en.wikipedia.org/wiki/Chromebook | Technology | Specific hardware | null |
The first two commercially available Chromebooks, the Samsung Series 5 and the Acer AC700, were unveiled on May 11, 2011, at the Google I/O developer conference. They were to begin selling through online channels, including Amazon and Best Buy in the United States, the United Kingdom, France, Germany, the Netherlands, ... | Chromebook | Wikipedia | 421 | 31747219 | https://en.wikipedia.org/wiki/Chromebook | Technology | Specific hardware | null |
In an article published on ZDNet in June 2011, entitled "Five Chromebook concerns for businesses", Steven J. Vaughan-Nichols faulted the devices for lack of virtual private network capability, not supporting some Wi-Fi security methods, in particular Wi-Fi Protected Access II (WPA2) Enterprise with Extensible Authentic... | Chromebook | Wikipedia | 419 | 31747219 | https://en.wikipedia.org/wiki/Chromebook | Technology | Specific hardware | null |
By January 2013, Acer's Chromebook sales were being driven by "heavy Internet users with educational institutions", and the platform represented 5–10 percent of the company's US shipments, according to Acer president Jim Wong. He called those numbers sustainable, contrasting them with low Windows 8 sales which he blame... | Chromebook | Wikipedia | 479 | 31747219 | https://en.wikipedia.org/wiki/Chromebook | Technology | Specific hardware | null |
The education market has been the Chromebooks' most notable success, competing on the low cost of the hardware, software and upkeep. The simplicity of the machines, which could be a drawback in other markets, has proven an advantage to school districts by reducing training and maintenance costs.
By January 2012, even ... | Chromebook | Wikipedia | 508 | 31747219 | https://en.wikipedia.org/wiki/Chromebook | Technology | Specific hardware | null |
Despite this, Chromebooks made up nearly 60% of computers used in US schools in March 2018. CNET writer Alfred Ng cited superior security as the main reason for this level of market adoption.
According to research firms Gartner and Canalys, over 30 million Chromebooks were shipped in 2020, as school districts and pare... | Chromebook | Wikipedia | 501 | 31747219 | https://en.wikipedia.org/wiki/Chromebook | Technology | Specific hardware | null |
The device's USB port is capable of supporting a keyboard, mouse, Ethernet adapter, or USB storage, but not a printer, as ChromeOS offers no print stack. Adding further hardware outside of the previously mentioned items will likely cause problems with the operating system's "self knowing" security model. Users instead ... | Chromebook | Wikipedia | 499 | 31747219 | https://en.wikipedia.org/wiki/Chromebook | Technology | Specific hardware | null |
The Cr-48 features an Intel Atom N455, a single-core processor clocked at 1.66 GHz, with 512 KB of cache and hyperthreading enabled. It also features 2 GB of removable DDR3 memory in a single SO-DIMM, integrated chipset graphics (Intel GMA 3150), and a 66 watt-hour battery. It has been found that the Intel NM10 chipset... | Chromebook | Wikipedia | 414 | 31747219 | https://en.wikipedia.org/wiki/Chromebook | Technology | Specific hardware | null |
Reviewing the Samsung Series 5 specifications, Scott Stein of CNET was unimpressed with a machine with a 12-inch screen and just 16 GB of onboard storage. "Chrome OS might be lighter than Windows XP, but we'd still prefer more media storage space. At this price, you could also get an Wi-Fi AMD E-350-powered ultraporta... | Chromebook | Wikipedia | 437 | 31747219 | https://en.wikipedia.org/wiki/Chromebook | Technology | Specific hardware | null |
Joe Wilcox of BetaNews wrote that "price to performance and how it compares to other choices" is "where Chromebook crumbles for many potential buyers." He noted that the new models sell for more than their predecessors, and while the price-performance ratio is quite favorable compared to the MacBook Air, "by the specs,... | Chromebook | Wikipedia | 448 | 31747219 | https://en.wikipedia.org/wiki/Chromebook | Technology | Specific hardware | null |
Samsung Chromebook 3
The Chromebook 3 is distinct from and distinguished from the similarly named Samsung Series 3 in several respects: newer (released 2016), different architecture (Intel Celeron N3050 instead of Exynos 5 Dual ARM Cortex), thinner (0.7"), and less expensive (about $100 less than the Series 3); while ... | Chromebook | Wikipedia | 316 | 31747219 | https://en.wikipedia.org/wiki/Chromebook | Technology | Specific hardware | null |
HP
HP's first Chromebook, and the largest Chromebook on the market at that time, was the Pavilion 14 Chromebook launched February 3, 2013. It had an Intel Celeron 847 CPU and either 2 GB or 4 GB of RAM. Battery life was not long, at just over 4 hours, but the larger form factor made it more friendly for all-day use. H... | Chromebook | Wikipedia | 475 | 31747219 | https://en.wikipedia.org/wiki/Chromebook | Technology | Specific hardware | null |
The Cretaceous–Paleogene (K–Pg) extinction event, also known as the K–T extinction, was the mass extinction of three-quarters of the plant and animal species on Earth approximately 66 million years ago. The event caused the extinction of all non-avian dinosaurs. Most other tetrapods weighing more than also became exti... | Cretaceous–Paleogene extinction event | Wikipedia | 467 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Other causal or contributing factors to the extinction may have been the Deccan Traps and other volcanic eruptions, climate change, and sea level change. However, in January 2020, scientists reported that climate-modeling of the extinction event favored the asteroid impact and not volcanism.
A wide range of terrestria... | Cretaceous–Paleogene extinction event | Wikipedia | 421 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Despite the event's severity, there was significant variability in the rate of extinction between and within different clades. Species that depended on photosynthesis declined or became extinct as atmospheric particles blocked sunlight and reduced the solar energy reaching the ground. This plant extinction caused a maj... | Cretaceous–Paleogene extinction event | Wikipedia | 503 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Despite the massive loss of life inferred to have occurred during the extinction, and a number of geologic formations worldwide that span the boundary, only a few fossil sites contain direct evidence of the mass mortality that occurred exactly at the K-Pg boundary. These include the Tanis site of the Hell Creek Formati... | Cretaceous–Paleogene extinction event | Wikipedia | 434 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Radiolaria have left a geological record since at least the Ordovician times, and their mineral fossil skeletons can be tracked across the K–Pg boundary. There is no evidence of mass extinction of these organisms, and there is support for high productivity of these species in southern high latitudes as a result of cool... | Cretaceous–Paleogene extinction event | Wikipedia | 433 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Ostracods, a class of small crustaceans that were prevalent in the upper Maastrichtian, left fossil deposits in a variety of locations. A review of these fossils shows that ostracod diversity was lower in the Paleocene than any other time in the Cenozoic. Current research cannot ascertain whether the extinctions occurr... | Cretaceous–Paleogene extinction event | Wikipedia | 386 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
The numbers of bivalve genera exhibited significant diminution after the K–Pg boundary. Entire groups of bivalves, including rudists (reef-building clams) and inoceramids (giant relatives of modern scallops), became extinct at the K–Pg boundary, with the gradual extinction of most inoceramid bivalves beginning well bef... | Cretaceous–Paleogene extinction event | Wikipedia | 441 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Approximately 35% of echinoderm genera became extinct at the K–Pg boundary, although taxa that thrived in low-latitude, shallow-water environments during the late Cretaceous had the highest extinction rate. Mid-latitude, deep-water echinoderms were much less affected at the K–Pg boundary. The pattern of extinction poin... | Cretaceous–Paleogene extinction event | Wikipedia | 475 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
In the Maastrichtian age, 28 shark families and 13 batoid families thrived, of which 25 and 9, respectively, survived the K–T boundary event. Forty-seven of all neoselachian genera cross the K–T boundary, with 85% being sharks. Batoids display with 15%, a comparably low survival rate. Among elasmobranchs, those species... | Cretaceous–Paleogene extinction event | Wikipedia | 448 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Choristoderes
The choristoderes (a group of semi-aquatic diapsids of uncertain position) survived across the K–Pg boundary subsequently becoming extinct in the Miocene. The gharial-like choristodere genus Champsosaurus palatal teeth suggest that there were dietary changes among the various species across the K–Pg even... | Cretaceous–Paleogene extinction event | Wikipedia | 511 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Marine reptiles
∆44/42Ca values indicate that prior to the mass extinction, marine reptiles at the top of food webs were feeding on only one source of calcium, suggesting their populations exhibited heightened vulnerability to extinctions at the terminus of the Cretaceous. Along with the aforementioned mosasaurs, plesi... | Cretaceous–Paleogene extinction event | Wikipedia | 395 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Pterosaurs
Two families of pterosaurs, Azhdarchidae and Nyctosauridae, were definitely present in the Maastrichtian, and they likely became extinct at the K–Pg boundary. Several other pterosaur lineages may have been present during the Maastrichtian, such as the ornithocheirids, pteranodontids, a possible tapejarid, a ... | Cretaceous–Paleogene extinction event | Wikipedia | 398 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
The growing consensus about the endothermy of dinosaurs (see dinosaur physiology) helps to understand their full extinction in contrast with their close relatives, the crocodilians. Ectothermic ("cold-blooded") crocodiles have very limited needs for food (they can survive several months without eating), while endotherm... | Cretaceous–Paleogene extinction event | Wikipedia | 191 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Whether the extinction occurred gradually or suddenly has been debated, as both views have support from the fossil record. A highly informative sequence of dinosaur-bearing rocks from the K–Pg boundary is found in western North America, particularly the late Maastrichtian-age Hell Creek Formation of Montana. Comparison... | Cretaceous–Paleogene extinction event | Wikipedia | 376 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Several researchers support the existence of Paleocene non-avian dinosaurs. Evidence of this existence is based on the discovery of dinosaur remains in the Hell Creek Formation up to above and 40,000 years later than the K–Pg boundary. Pollen samples recovered near a fossilized hadrosaur femur recovered in the Ojo Ala... | Cretaceous–Paleogene extinction event | Wikipedia | 336 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Only a small fraction of ground and water-dwelling Cretaceous bird species survived the impact, giving rise to today's birds. The only bird group known for certain to have survived the K–Pg boundary is the Aves. Avians may have been able to survive the extinction as a result of their abilities to dive, swim, or seek sh... | Cretaceous–Paleogene extinction event | Wikipedia | 247 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Mammals
Mammalian species began diversifying approximately 30 million years prior to the K–Pg boundary. Diversification of mammals stalled across the boundary. All major Late Cretaceous mammalian lineages, including monotremes (egg-laying mammals), multituberculates, metatherians (which includes modern marsupials), eu... | Cretaceous–Paleogene extinction event | Wikipedia | 341 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
After the K–Pg extinction, mammals evolved to fill the niches left vacant by the dinosaurs. Some research indicates that mammals did not explosively diversify across the K–Pg boundary, despite the ecological niches made available by the extinction of dinosaurs. Several mammalian orders have been interpreted as diversif... | Cretaceous–Paleogene extinction event | Wikipedia | 485 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Due to the wholesale destruction of plants at the K–Pg boundary, there was a proliferation of saprotrophic organisms, such as fungi, that do not require photosynthesis and use nutrients from decaying vegetation. The dominance of fungal species lasted only a few years while the atmosphere cleared and plenty of organic m... | Cretaceous–Paleogene extinction event | Wikipedia | 503 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
The proliferation of fungi has occurred after several extinction events, including the Permian–Triassic extinction event, the largest known mass extinction in Earth's history, with up to 96% of all species suffering extinction.
Dating
A 1991 study of fossil leaves dated the extinction-associated freezing to early Ju... | Cretaceous–Paleogene extinction event | Wikipedia | 342 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
The sedimentation rate and thickness of K–Pg clay from three sites suggest rapid extinction, perhaps over a period of less than 10,000 years. At one site in the Denver Basin of Colorado, after the K–Pg boundary layer was deposited, the fern spike lasted approximately 1,000 years, and no more than 71,000 years; at the s... | Cretaceous–Paleogene extinction event | Wikipedia | 194 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
In 1980, a team of researchers consisting of Nobel Prize-winning physicist Luis Alvarez, his son, geologist Walter Alvarez, and chemists Frank Asaro and Helen Michel discovered that sedimentary layers found all over the world at the Cretaceous–Paleogene boundary contain a concentration of iridium many times greater tha... | Cretaceous–Paleogene extinction event | Wikipedia | 494 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Additional evidence for the impact event is found at the Tanis site in southwestern North Dakota, United States. Tanis is part of the heavily studied Hell Creek Formation, a group of rocks spanning four states in North America renowned for many significant fossil discoveries from the Upper Cretaceous and lower Paleocen... | Cretaceous–Paleogene extinction event | Wikipedia | 198 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
Some critics of the impact theory have put forward that the impact precedes the mass extinction by about 300,000 years and thus was not its cause. However, in a 2013 paper, Paul Renne of the Berkeley Geochronology Center dated the impact at years ago, based on argon–argon dating. He further posits that the mass extinc... | Cretaceous–Paleogene extinction event | Wikipedia | 494 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
The re-entry of ejecta into Earth's atmosphere included a brief (hours-long) but intense pulse of infrared radiation, cooking exposed organisms. This is debated, with opponents arguing that local ferocious fires, probably limited to North America, fall short of global firestorms. This is the "Cretaceous–Paleogene fires... | Cretaceous–Paleogene extinction event | Wikipedia | 197 | 44503418 | https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene%20extinction%20event | Physical sciences | Geological history | null |
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