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In the early 1990s, industrial hemp agriculture in North America began with the Hemp Awareness Committee at the University of Manitoba. The Committee worked with the provincial government to get research and development assistance and was able to obtain test plot permits from the Canadian government. Their efforts led ... | Hemp | Wikipedia | 435 | 963313 | https://en.wikipedia.org/wiki/Hemp | Biology and health sciences | Rosales | Plants | vital_articles |
United Kingdom
In the United Kingdom, cultivation licenses are issued by the Home Office under the Misuse of Drugs Act 1971. When grown for nondrug purposes, hemp is referred to as industrial hemp, and a common product is fiber for use in a wide variety of products, as well as the seed for nutritional aspects and the o... | Hemp | Wikipedia | 374 | 963313 | https://en.wikipedia.org/wiki/Hemp | Biology and health sciences | Rosales | Plants | vital_articles |
The process to legalize hemp cultivation began in 2009, when Oregon began approving licenses for industrial hemp. Then, in 2013, after the legalization of marijuana, several farmers in Colorado planted and harvested several acres of hemp, bringing in the first hemp crop in the United States in over half a century. Afte... | Hemp | Wikipedia | 481 | 963313 | https://en.wikipedia.org/wiki/Hemp | Biology and health sciences | Rosales | Plants | vital_articles |
Textile expert Elizabeth Wayland Barber summarizes the historical evidence that Cannabis sativa, "grew and was known in the Neolithic period all across the northern latitudes, from Europe (Germany, Switzerland, Austria, Romania, Ukraine) to East Asia (Tibet and China)," but, "textile use of Cannabis sativa does not sur... | Hemp | Wikipedia | 327 | 963313 | https://en.wikipedia.org/wiki/Hemp | Biology and health sciences | Rosales | Plants | vital_articles |
The Spaniards brought hemp to the Americas and cultivated it in Chile starting about 1545. Similar attempts were made in Peru, Colombia, and Mexico, but only in Chile did the crop find success. In July 1605, Samuel Champlain reported the use of grass and hemp clothing by the (Wampanoag) people of Cape Cod and the (Naus... | Hemp | Wikipedia | 403 | 963313 | https://en.wikipedia.org/wiki/Hemp | Biology and health sciences | Rosales | Plants | vital_articles |
George Washington also imported the Indian hemp plant from Asia, which was used for fiber and, by some growers, for intoxicating resin production. In a 1796 letter to William Pearce who managed the plants for him, Washington says, "What was done with the Indian Hemp plant from last summer? It ought, all of it, to be so... | Hemp | Wikipedia | 475 | 963313 | https://en.wikipedia.org/wiki/Hemp | Biology and health sciences | Rosales | Plants | vital_articles |
While the Marijuana Tax Act of 1937 had just been signed into law, the United States Department of Agriculture lifted the tax on hemp cultivation during WWII. Before WWII, the U.S. Navy used Jute and Manila Hemp from the Philippines and Indonesia for the cordage on their ships. During the war, Japan cut off those suppl... | Hemp | Wikipedia | 489 | 963313 | https://en.wikipedia.org/wiki/Hemp | Biology and health sciences | Rosales | Plants | vital_articles |
In Japan, hemp was historically used as paper and a fiber crop. There is archaeological evidence cannabis was used for clothing and the seeds were eaten in Japan back to the Jōmon period (10,000 to 300 BC). Many Kimono designs portray hemp, or asa (), as a beautiful plant. In 1948, marijuana was restricted as a narcoti... | Hemp | Wikipedia | 340 | 963313 | https://en.wikipedia.org/wiki/Hemp | Biology and health sciences | Rosales | Plants | vital_articles |
Messier 49 (also known as M49 or NGC 4472) is a giant elliptical galaxy about away in the equatorial constellation of Virgo. This galaxy was discovered by astronomer Charles Messier in 1777.
As an elliptical galaxy, Messier 49 has the physical form of a radio galaxy, but it only has the radio emission of a normal gal... | Messier 49 | Wikipedia | 445 | 963403 | https://en.wikipedia.org/wiki/Messier%2049 | Physical sciences | Notable galaxies | Astronomy | vital_articles |
A fireplace or hearth is a structure made of brick, stone or metal designed to contain a fire. Fireplaces are used for the relaxing ambiance they create and for heating a room. Modern fireplaces vary in heat efficiency, depending on the design.
Historically, they were used for heating a dwelling, cooking, and heating ... | Fireplace | Wikipedia | 495 | 963967 | https://en.wikipedia.org/wiki/Fireplace | Technology | Other components | null | vital_articles |
Ventless fireplaces (duct free/room-venting fireplaces) are fueled by either gel, liquid propane, bottled gas or natural gas. In the United States, some states and local counties have laws restricting these types of fireplaces. They must be properly sized to the area to be heated. There are also air quality control iss... | Fireplace | Wikipedia | 507 | 963967 | https://en.wikipedia.org/wiki/Fireplace | Technology | Other components | null | vital_articles |
Fire pits developed into raised hearths in buildings, but venting smoke depended on open windows or holes in roofs. The medieval great hall typically had a centrally located hearth, where an open fire burned with the smoke rising to the vent in the roof. Louvers were developed during the Middle Ages to allow the roof v... | Fireplace | Wikipedia | 499 | 963967 | https://en.wikipedia.org/wiki/Fireplace | Technology | Other components | null | vital_articles |
Many flaws were found in early fireplace designs. Along with the Industrial Revolution, came large-scale housing developments, necessitating a standardization of fireplaces. The most renowned fireplace designers of this time were the Adam Brothers: John Adam, Robert Adam, and James Adam. They perfected a style of firep... | Fireplace | Wikipedia | 492 | 963967 | https://en.wikipedia.org/wiki/Fireplace | Technology | Other components | null | vital_articles |
Wood
A literature review published in the Journal of Toxicology and Environmental Health concludes that there are a wide variety of health risks posed by residential wood combustion. It states:
The Washington State Department of Ecology also published a booklet explaining why wood smoke can be dangerous. It explains t... | Fireplace | Wikipedia | 352 | 963967 | https://en.wikipedia.org/wiki/Fireplace | Technology | Other components | null | vital_articles |
Several of these terms may be compounded with chimney or fireplace such as chimney-back.
Andiron—Either one of two horizontal metal bars resting on short legs intended to support firewood in a hearth.
Arch—An arched top of the fireplace opening.
Ash dump—An opening in a hearth to sweep ashes for later removal from t... | Fireplace | Wikipedia | 332 | 963967 | https://en.wikipedia.org/wiki/Fireplace | Technology | Other components | null | vital_articles |
A scale or balance is a device used to measure weight or mass. These are also known as mass scales, weight scales, mass balances, massometers, and weight balances.
The traditional scale consists of two plates or bowls suspended at equal distances from a fulcrum. One plate holds an object of unknown mass (or weight), w... | Weighing scale | Wikipedia | 426 | 964428 | https://en.wikipedia.org/wiki/Weighing%20scale | Physical sciences | Classical mechanics | null | vital_articles |
Examples, dating , have also been found in the Indus River valley. Uniform, polished stone cubes discovered in early settlements were probably used as mass-setting stones in balance scales. Although the cubes bear no markings, their masses are multiples of a common denominator. The cubes are made of many different kin... | Weighing scale | Wikipedia | 462 | 964428 | https://en.wikipedia.org/wiki/Weighing%20scale | Physical sciences | Classical mechanics | null | vital_articles |
The balance (also balance scale, beam balance and laboratory balance) was the first mass measuring instrument invented. In its traditional form, it consists of a pivoted horizontal lever with arms of equal lengththe beam or tron and a weighing pan suspended from each arm (hence the plural name "scales for a weighing in... | Weighing scale | Wikipedia | 394 | 964428 | https://en.wikipedia.org/wiki/Weighing%20scale | Physical sciences | Classical mechanics | null | vital_articles |
To reduce the need for large reference masses, an off-center beam can be used. A balance with an off-center beam can be almost as accurate as a scale with a center beam, but the off-center beam requires special reference masses and cannot be intrinsically checked for accuracy by simply swapping the contents of the pans... | Weighing scale | Wikipedia | 454 | 964428 | https://en.wikipedia.org/wiki/Weighing%20scale | Physical sciences | Classical mechanics | null | vital_articles |
Further developments have included a "gear balance" in which the parallelogram is replaced by any odd number of interlocking gears greater than one, with alternating gears of the same size and with the central gear fixed to a stand and the outside gears fixed to pans, as well as the "sprocket gear balance" consisting o... | Weighing scale | Wikipedia | 327 | 964428 | https://en.wikipedia.org/wiki/Weighing%20scale | Physical sciences | Classical mechanics | null | vital_articles |
An analytical balance is a class of balance designed to measure small mass in the sub-milligram range. The measuring pan of an analytical balance (0.1 mg or better) is inside a transparent enclosure with doors so that dust does not collect and so any air currents in the room do not affect the balance's operation. This... | Weighing scale | Wikipedia | 475 | 964428 | https://en.wikipedia.org/wiki/Weighing%20scale | Physical sciences | Classical mechanics | null | vital_articles |
Scales also are widely used as a symbol of finance, commerce, or trade, in which they have played a traditional, vital role since ancient times. For instance, balance scales are depicted in the seal of the U.S. Department of the Treasury and the Federal Trade Commission.
Scales are also the symbol for the astrological... | Weighing scale | Wikipedia | 478 | 964428 | https://en.wikipedia.org/wiki/Weighing%20scale | Physical sciences | Classical mechanics | null | vital_articles |
In a spring scale, the spring either stretches (as in a hanging scale in the produce department of a grocery store) or compresses (as in a simple bathroom scale). By Hooke's law, every spring has a proportionality constant that relates how hard it is pulled to how far it stretches. Weighing scales use a spring with a k... | Weighing scale | Wikipedia | 494 | 964428 | https://en.wikipedia.org/wiki/Weighing%20scale | Physical sciences | Classical mechanics | null | vital_articles |
Digital bathroom scale
A digital bathroom scale is a scale on the floor which a person stands on. The weight is shown on an LED or LCD display. The digital electronics may do more than just display weight, it may calculate body fat, BMI, lean mass, muscle mass, and water ratio. Some modern bathroom scales are wireles... | Weighing scale | Wikipedia | 476 | 964428 | https://en.wikipedia.org/wiki/Weighing%20scale | Physical sciences | Classical mechanics | null | vital_articles |
Weighbridges : A large scale that can weigh trucks, lorries, containers, and other heavy-duty vehicles. They are used in industries like manufacturing, shipping, mining, agriculture, etc
Container Stacker Scale : A container stacker scale is a specialized weighing system designed for accurately measuring the weight of... | Weighing scale | Wikipedia | 434 | 964428 | https://en.wikipedia.org/wiki/Weighing%20scale | Physical sciences | Classical mechanics | null | vital_articles |
Wheel Loader Scale : A wheel loader scale is a system that measures the weight of the materials lifted by a wheel loader, a type of heavy machinery used for moving large amounts of earth, sand, gravel, or other materials. A wheel loader scale can help improve the efficiency and accuracy of loading operations, as well a... | Weighing scale | Wikipedia | 482 | 964428 | https://en.wikipedia.org/wiki/Weighing%20scale | Physical sciences | Classical mechanics | null | vital_articles |
Because gravity varies by over 0.5% over the surface of the earth, the distinction between force due to gravity and mass is relevant for accurate calibration of scales for commercial purposes. Usually, the goal is to measure the mass of the sample rather than its force due to gravity at that particular location.
Tradi... | Weighing scale | Wikipedia | 372 | 964428 | https://en.wikipedia.org/wiki/Weighing%20scale | Physical sciences | Classical mechanics | null | vital_articles |
Elastic arm scale
In 2014 a concept of hybrid scale was introduced, the elastically deformable arm scale, which is a combination between a spring scale and a beam balance, exploiting simultaneously both principles of equilibrium and deformation. In this scale, the rigid arms of a classical beam balance (for example a s... | Weighing scale | Wikipedia | 158 | 964428 | https://en.wikipedia.org/wiki/Weighing%20scale | Physical sciences | Classical mechanics | null | vital_articles |
A dwarf galaxy is a small galaxy composed of about 1000 up to several billion stars, as compared to the Milky Way's 200–400 billion stars. The Large Magellanic Cloud, which closely orbits the Milky Way and contains over 30 billion stars, is sometimes classified as a dwarf galaxy; others consider it a full-fledged galax... | Dwarf galaxy | Wikipedia | 483 | 964475 | https://en.wikipedia.org/wiki/Dwarf%20galaxy | Physical sciences | Galaxy morphological classification | null | vital_articles |
In astronomy, a blue compact dwarf galaxy (BCD galaxy) is a small galaxy which contains large clusters of young, hot, massive stars. These stars, the brightest of which are blue, cause the galaxy itself to appear blue in colour. Most BCD galaxies are also classified as dwarf irregular galaxies or as dwarf lenticular ga... | Dwarf galaxy | Wikipedia | 390 | 964475 | https://en.wikipedia.org/wiki/Dwarf%20galaxy | Physical sciences | Galaxy morphological classification | null | vital_articles |
Ultra-compact dwarfs
Ultra-compact dwarf galaxies (UCD) are a class of very compact galaxies with very high stellar densities,
discovered in the 2000s.
They are thought to be on the order of 200 light years across, containing about 100 million stars. It is theorised that these are the cores of nucleated dwarf elliptica... | Dwarf galaxy | Wikipedia | 481 | 964475 | https://en.wikipedia.org/wiki/Dwarf%20galaxy | Physical sciences | Galaxy morphological classification | null | vital_articles |
The Spanish dancer, scientific name Hexabranchus sanguineus (literally meaning "blood-colored six-gills"), is a dorid nudibranch, a very large and colorful sea slug, a marine gastropod mollusk in the family Hexabranchidae.The taxonomy of the genus Hexabranchus has been controversial but a thorough molecular and morphol... | Spanish dancer | Wikipedia | 335 | 965247 | https://en.wikipedia.org/wiki/Spanish%20dancer | Biology and health sciences | Gastropods | Animals | vital_articles |
Biology
During daytime, the Spanish dancer hides away from the light in the crevices of its natural habitat to only come out late at night.
It feeds on various species of sponge.
Like all nudibranchs, it is hermaphrodite and its bright red to pink egg ribbon has a spiral shape related to the size of the animal so relat... | Spanish dancer | Wikipedia | 202 | 965247 | https://en.wikipedia.org/wiki/Spanish%20dancer | Biology and health sciences | Gastropods | Animals | vital_articles |
An antimicrobial is an agent that kills microorganisms (microbicide) or stops their growth (bacteriostatic agent). Antimicrobial medicines can be grouped according to the microorganisms they act primarily against. For example, antibiotics are used against bacteria, and antifungals are used against fungi. They can also ... | Antimicrobial | Wikipedia | 466 | 965323 | https://en.wikipedia.org/wiki/Antimicrobial | Biology and health sciences | Anti-infectives | Health | vital_articles |
In the 19th century, microbiologists such as Louis Pasteur and Jules Francois Joubert observed antagonism between some bacteria and discussed the merits of controlling these interactions in medicine. Louis Pasteur's work in fermentation and spontaneous generation led to the distinction between anaerobic and aerobic bac... | Antimicrobial | Wikipedia | 408 | 965323 | https://en.wikipedia.org/wiki/Antimicrobial | Biology and health sciences | Anti-infectives | Health | vital_articles |
The discovery, development and use of antibacterials during the 20th century have reduced mortality from bacterial infections. The antibiotic era began with the therapeutic application of sulfonamide drugs in 1936, followed by a "golden" period of discovery from about 1945 to 1970, when a number of structurally diverse... | Antimicrobial | Wikipedia | 416 | 965323 | https://en.wikipedia.org/wiki/Antimicrobial | Biology and health sciences | Anti-infectives | Health | vital_articles |
As well as their use in medicine, antifungals are frequently sought after to control indoor mold in damp or wet home materials. Sodium bicarbonate (baking soda) blasted on to surfaces acts as an antifungal. Another antifungal solution applied after or without blasting by soda is a mix of hydrogen peroxide and a thin su... | Antimicrobial | Wikipedia | 486 | 965323 | https://en.wikipedia.org/wiki/Antimicrobial | Biology and health sciences | Anti-infectives | Health | vital_articles |
A wide range of chemical and natural compounds are used as antimicrobials. Organic acids and their salts are used widely in food products, e.g. lactic acid, citric acid, acetic acid, either as ingredients or as disinfectants. For example, beef carcasses often are sprayed with acids, and then rinsed or steamed, to reduc... | Antimicrobial | Wikipedia | 483 | 965323 | https://en.wikipedia.org/wiki/Antimicrobial | Biology and health sciences | Anti-infectives | Health | vital_articles |
Antimicrobial pesticides
According to the U.S. Environmental Protection Agency (EPA), and defined by the Federal Insecticide, Fungicide, and Rodenticide Act, antimicrobial pesticides are used to control growth of microbes through disinfection, sanitation, or reduction of development and to protect inanimate objects, in... | Antimicrobial | Wikipedia | 499 | 965323 | https://en.wikipedia.org/wiki/Antimicrobial | Biology and health sciences | Anti-infectives | Health | vital_articles |
Ozone can kill microorganisms in air, water and process equipment and has been used in settings such as kitchen exhaust ventilation, garbage rooms, grease traps, biogas plants, wastewater treatment plants, textile production, breweries, dairies, food and hygiene production, pharmaceutical industries, bottling plants, z... | Antimicrobial | Wikipedia | 224 | 965323 | https://en.wikipedia.org/wiki/Antimicrobial | Biology and health sciences | Anti-infectives | Health | vital_articles |
Halogens
Elements such as chlorine, iodine, fluorine, and bromine are nonmetallic in nature and constitute the halogen family. Each of these halogens have a different antimicrobial effect that is influenced by various factors such as pH, temperature, contact time, and type of microorganism. Chlorine and iodine are the... | Antimicrobial | Wikipedia | 389 | 965323 | https://en.wikipedia.org/wiki/Antimicrobial | Biology and health sciences | Anti-infectives | Health | vital_articles |
Alcohols
Alcohols are commonly used as disinfectants and antiseptics. Alcohols kill vegetative bacteria, most viruses and fungi. Ethyl alcohol, n-propanol and isopropyl alcohol are the most commonly used antimicrobial agents. Methanol is also a disinfecting agent but is not generally used as it is highly poisonous. Es... | Antimicrobial | Wikipedia | 285 | 965323 | https://en.wikipedia.org/wiki/Antimicrobial | Biology and health sciences | Anti-infectives | Health | vital_articles |
Phenol and Phenolic compounds
Phenol, also known as carbolic acid, was one of the first chemicals which was used as an antimicrobial agent. It has high antiseptic properties. It is bacteriostatic at concentrations of 0.1%–1% and is bactericidal/fungicidal at 1%–2%. A 5% solution kills anthrax spores in 48 hr. Phenols ... | Antimicrobial | Wikipedia | 456 | 965323 | https://en.wikipedia.org/wiki/Antimicrobial | Biology and health sciences | Anti-infectives | Health | vital_articles |
Aldehydes
Aldehydes are highly effective against bacteria, fungi, and viruses. Aldehydes inhibit bacterial growth by disrupting the outer membrane. They are used in the disinfection and sterilization of surgical instruments. As they are highly toxic, they are not used in antiseptics. Currently, only three aldehyde co... | Antimicrobial | Wikipedia | 509 | 965323 | https://en.wikipedia.org/wiki/Antimicrobial | Biology and health sciences | Anti-infectives | Health | vital_articles |
Desiccation
Desiccation is also known as dehydration. It is the state of extreme dryness or the process of extreme drying. Some microorganisms like bacteria, yeasts and molds require water for their growth. Desiccation dries up the water content thus inhibiting microbial growth. On the availability of water, the bact... | Antimicrobial | Wikipedia | 458 | 965323 | https://en.wikipedia.org/wiki/Antimicrobial | Biology and health sciences | Anti-infectives | Health | vital_articles |
The roller is an agricultural tool used for flattening land or breaking up large clumps of soil, especially after ploughing or disc harrowing. Typically, rollers are pulled by tractors or, prior to mechanisation, a team of animals such as horses or oxen. As well as for agricultural purposes, rollers are used on cricket... | Roller (agricultural tool) | Wikipedia | 415 | 965924 | https://en.wikipedia.org/wiki/Roller%20%28agricultural%20tool%29 | Technology | Agricultural tools | null | vital_articles |
Farming use
Rollers are a secondary tillage tool used for flattening land or breaking up large clumps of soil, especially after ploughing or disc harrowing. Rollers are typically pulled by tractors today. Before mechanised agriculture, a team of working animals such as horses or oxen provided the power. Animal power is... | Roller (agricultural tool) | Wikipedia | 486 | 965924 | https://en.wikipedia.org/wiki/Roller%20%28agricultural%20tool%29 | Technology | Agricultural tools | null | vital_articles |
Lawn rollers are designed to even out or firm up the lawn surface, especially in climates where heaving causes the lawn to be lumpy. Heaving may result when the ground freezes and thaws many times over winter. Where this occurs, gardeners are advised to give the lawn a light rolling with a lawn roller in the spring. Cl... | Roller (agricultural tool) | Wikipedia | 81 | 965924 | https://en.wikipedia.org/wiki/Roller%20%28agricultural%20tool%29 | Technology | Agricultural tools | null | vital_articles |
The inverse second or reciprocal second (s−1), also called per second, is a unit defined as the multiplicative inverse of the second (a unit of time). It is applicable for physical quantities of dimension reciprocal time, such as frequency and strain rate.
It is dimensionally equivalent to:
hertz (Hz), historically k... | Inverse second | Wikipedia | 319 | 11694119 | https://en.wikipedia.org/wiki/Inverse%20second | Physical sciences | Angular velocity | Basics and measurement | vital_articles |
Sugar alcohols (also called polyhydric alcohols, polyalcohols, alditols or glycitols) are organic compounds, typically derived from sugars, containing one hydroxyl group attached to each carbon atom. They are white, water-soluble solids that can occur naturally or be produced industrially by hydrogenating sugars. Sinc... | Sugar alcohol | Wikipedia | 501 | 562526 | https://en.wikipedia.org/wiki/Sugar%20alcohol | Physical sciences | Sugar alcohols | Chemistry | vital_articles |
Health effects
Sugar alcohols do not contribute to tooth decay; in fact, xylitol deters tooth decay.
Sugar alcohols are absorbed at 50% of the rate of sugars, resulting in less of an effect on blood sugar levels as measured by comparing their effect to sucrose using the glycemic index.
Common sugar alcohols
Ethylene... | Sugar alcohol | Wikipedia | 467 | 562526 | https://en.wikipedia.org/wiki/Sugar%20alcohol | Physical sciences | Sugar alcohols | Chemistry | vital_articles |
In addition to their sweetness, some sugar alcohols can produce a noticeable cooling sensation in the mouth when highly concentrated, for instance in sugar-free hard candy or chewing gum. This happens, for example, with the crystalline phase of sorbitol, erythritol, xylitol, mannitol, lactitol and maltitol. The cooling... | Sugar alcohol | Wikipedia | 300 | 562526 | https://en.wikipedia.org/wiki/Sugar%20alcohol | Physical sciences | Sugar alcohols | Chemistry | vital_articles |
In graph theory, a vertex cover (sometimes node cover) of a graph is a set of vertices that includes at least one endpoint of every edge of the graph.
In computer science, the problem of finding a minimum vertex cover is a classical optimization problem. It is NP-hard, so it cannot be solved by a polynomial-time alg... | Vertex cover | Wikipedia | 510 | 562782 | https://en.wikipedia.org/wiki/Vertex%20cover | Mathematics | Graph theory | null | vital_articles |
The vertex cover problem is an NP-complete problem: it was one of Karp's 21 NP-complete problems. It is often used in computational complexity theory as a starting point for NP-hardness proofs.
ILP formulation
Assume that every vertex has an associated cost of .
The (weighted) minimum vertex cover problem can be formu... | Vertex cover | Wikipedia | 460 | 562782 | https://en.wikipedia.org/wiki/Vertex%20cover | Mathematics | Graph theory | null | vital_articles |
An exhaustive search algorithm can solve the problem in time 2knO(1), where k is the size of the vertex cover. Vertex cover is therefore fixed-parameter tractable, and if we are only interested in small k, we can solve the problem in polynomial time. One algorithmic technique that works here is called bounded search tr... | Vertex cover | Wikipedia | 388 | 562782 | https://en.wikipedia.org/wiki/Vertex%20cover | Mathematics | Graph theory | null | vital_articles |
The set C constructed this way is a vertex cover: suppose that an edge e is not covered by C; then M ∪ {e} is a matching and e ∉ M, which is a contradiction with the assumption that M is maximal. Furthermore, if e = {u, v} ∈ M, then any vertex cover – including an optimal vertex cover – must contain u or v (or both); o... | Vertex cover | Wikipedia | 432 | 562782 | https://en.wikipedia.org/wiki/Vertex%20cover | Mathematics | Graph theory | null | vital_articles |
Applications
Vertex cover optimization serves as a model for many real-world and theoretical problems. For example, a commercial establishment interested in installing the fewest possible closed circuit cameras covering all hallways (edges) connecting all rooms (nodes) on a floor might model the objective as a vertex ... | Vertex cover | Wikipedia | 83 | 562782 | https://en.wikipedia.org/wiki/Vertex%20cover | Mathematics | Graph theory | null | vital_articles |
In mathematics and logic, a higher-order logic (abbreviated HOL) is a form of logic that is distinguished from first-order logic by additional quantifiers and, sometimes, stronger semantics. Higher-order logics with their standard semantics are more expressive, but their model-theoretic properties are less well-behaved... | Higher-order logic | Wikipedia | 291 | 562883 | https://en.wikipedia.org/wiki/Higher-order%20logic | Mathematics | Mathematical logic | null | vital_articles |
In the standard or full semantics, quantifiers over higher-type objects range over all possible objects of that type. For example, a quantifier over sets of individuals ranges over the entire powerset of the set of individuals. Thus, in standard semantics, once the set of individuals is specified, this is enough to spe... | Higher-order logic | Wikipedia | 512 | 562883 | https://en.wikipedia.org/wiki/Higher-order%20logic | Mathematics | Mathematical logic | null | vital_articles |
The term "higher-order logic" is assumed in some context to refer to classical higher-order logic. However, modal higher-order logic has been studied as well. According to several logicians, Gödel's ontological proof is best studied (from a technical perspective) in such a context. | Higher-order logic | Wikipedia | 63 | 562883 | https://en.wikipedia.org/wiki/Higher-order%20logic | Mathematics | Mathematical logic | null | vital_articles |
Signs and symptoms are diagnostic indications of an illness, injury, or condition.
Signs are objective and externally observable; symptoms are a person's reported subjective experiences.
A sign for example may be a higher or lower temperature than normal, raised or lowered blood pressure or an abnormality showing on ... | Signs and symptoms | Wikipedia | 497 | 562958 | https://en.wikipedia.org/wiki/Signs%20and%20symptoms | Biology and health sciences | Symptoms and signs | Health | vital_articles |
Symptomatic
When a disease is evidenced by symptoms it is known as symptomatic. There are many conditions including subclinical infections that display no symptoms, and these are termed asymptomatic.
Signs and symptoms may be mild or severe, brief or longer-lasting when they may become reduced (remission), or then re... | Signs and symptoms | Wikipedia | 504 | 562958 | https://en.wikipedia.org/wiki/Signs%20and%20symptoms | Biology and health sciences | Symptoms and signs | Health | vital_articles |
Vital signs
Vital signs are the four signs that can give an immediate measurement of the body's overall functioning and health status. They are temperature, heart rate, breathing rate, and blood pressure. The ranges of these measurements vary with age, weight, gender and with general health.
A digital application has ... | Signs and symptoms | Wikipedia | 490 | 562958 | https://en.wikipedia.org/wiki/Signs%20and%20symptoms | Biology and health sciences | Symptoms and signs | Health | vital_articles |
Positive and negative
Sensory symptoms can also be described as positive symptoms, or as negative symptoms depending on whether the symptom is abnormally present such as tingling or itchiness, or abnormally absent such as loss of smell. The following terms are used for negative symptoms – hypoesthesia is a partial loss... | Signs and symptoms | Wikipedia | 508 | 562958 | https://en.wikipedia.org/wiki/Signs%20and%20symptoms | Biology and health sciences | Symptoms and signs | Health | vital_articles |
Cardinal
Cardinal signs and symptoms are those that may be diagnostic, and pathognomonic – of a certainty of diagnosis. Inflammation for example has a recognised group of cardinal signs and symptoms, as does exacerbations of chronic bronchitis, and Parkinson's disease.
In contrast to a pathognomonic cardinal sign, the... | Signs and symptoms | Wikipedia | 457 | 562958 | https://en.wikipedia.org/wiki/Signs%20and%20symptoms | Biology and health sciences | Symptoms and signs | Health | vital_articles |
Symptomatology
A symptom (from Greek σύμπτωμα, "accident, misfortune, that which befalls", from συμπίπτω, "I befall", from συν- "together, with" and πίπτω, "I fall") is a departure from normal function or feeling. Symptomatology (also called semiology) is a branch of medicine dealing with the signs and symptoms of a di... | Signs and symptoms | Wikipedia | 237 | 562958 | https://en.wikipedia.org/wiki/Signs%20and%20symptoms | Biology and health sciences | Symptoms and signs | Health | vital_articles |
A number of advances introduced mostly in the 19th century, allowed for more objective assessment by the physician in search of a diagnosis, and less need of input from the patient. During the 20th century the introduction of a wide range of imaging techniques and other testing methods such as genetic testing, clinical... | Signs and symptoms | Wikipedia | 487 | 562958 | https://en.wikipedia.org/wiki/Signs%20and%20symptoms | Biology and health sciences | Symptoms and signs | Health | vital_articles |
The 1896 introduction of the sphygmomanometer, designed by Scipione Riva-Rocci (1863–1937), to measure blood pressure. | Signs and symptoms | Wikipedia | 32 | 562958 | https://en.wikipedia.org/wiki/Signs%20and%20symptoms | Biology and health sciences | Symptoms and signs | Health | vital_articles |
Diagnosis
The recognition of signs, and noting of symptoms may lead to a diagnosis. Otherwise a physical examination may be carried out, and a medical history taken. Further diagnostic medical tests such as blood tests, scans, and biopsies, may be needed. An X-ray for example would soon be diagnostic of a suspected bo... | Signs and symptoms | Wikipedia | 177 | 562958 | https://en.wikipedia.org/wiki/Signs%20and%20symptoms | Biology and health sciences | Symptoms and signs | Health | vital_articles |
The sun bear (Helarctos malayanus) is a bear species in the family Ursidae found in the tropical forests of Southeast Asia. It is the only species in the genus Helarctos and the smallest bear species, standing nearly at the shoulder and weighing . It is stockily built, with large paws, strongly curved claws, small, ro... | Sun bear | Wikipedia | 478 | 563137 | https://en.wikipedia.org/wiki/Sun%20bear | Biology and health sciences | Bears | Animals | vital_articles |
Taxonomy and phylogeny
The scientific name Ursus malayanus was proposed by Stamford Raffles in 1821 when he first described a sun bear from Sumatra. In 1825, Thomas Horsfield placed the species in a genus of its own, Helarctos, when describing a sun bear from Borneo.
Subspecies and distribution
H. annamiticus, descr... | Sun bear | Wikipedia | 370 | 563137 | https://en.wikipedia.org/wiki/Sun%20bear | Biology and health sciences | Bears | Animals | vital_articles |
The sun bear is named so for its characteristic orange- to cream-coloured, crescent-like chest patch.
It is the smallest of all bear species. It is stockily built, with large paws, strongly curved claws, small rounded ears and a short snout. The head-and-body length is between , and the shoulder height is nearly . Adul... | Sun bear | Wikipedia | 348 | 563137 | https://en.wikipedia.org/wiki/Sun%20bear | Biology and health sciences | Bears | Animals | vital_articles |
During feeding, the sun bear can extend its exceptionally long tongue to extract insects and honey. The teeth are very large, especially the canines, and the bite force quotient is high relative to its body size for reasons not well understood; a possible explanation could be its frequent opening of tropical hardwood t... | Sun bear | Wikipedia | 352 | 563137 | https://en.wikipedia.org/wiki/Sun%20bear | Biology and health sciences | Bears | Animals | vital_articles |
Sun bears are shy and reclusive animals, and usually do not attack humans unless provoked to do so, or if they are injured or with their cubs; their timid nature led these bears to be often tamed and kept as pets in the past. Other sources, though, state that sun bears are known as very fierce animals when surprised in... | Sun bear | Wikipedia | 313 | 563137 | https://en.wikipedia.org/wiki/Sun%20bear | Biology and health sciences | Bears | Animals | vital_articles |
Sun bears are omnivores and feed on a broad variety of items, such as ants, bees, beetles, honey, termites, and plant material such as seeds and several kinds of fruits. Vertebrates such as birds, deer, eggs, and reptiles may be eaten occasionally. They forage mostly at night. Sun bears tear open hollow trees with thei... | Sun bear | Wikipedia | 459 | 563137 | https://en.wikipedia.org/wiki/Sun%20bear | Biology and health sciences | Bears | Animals | vital_articles |
The sun bear is native to the tropical forests of Southeast Asia; its range is bound by northeastern India to the north and extends south to Bangladesh, Myanmar, Thailand, Cambodia, Laos, and Vietnam to Brunei, Indonesia, and Malaysia to the south. Its presence in China was confirmed in 2017 when it was sighted in Ying... | Sun bear | Wikipedia | 438 | 563137 | https://en.wikipedia.org/wiki/Sun%20bear | Biology and health sciences | Bears | Animals | vital_articles |
Fossil remains suggest its occurrence farther north during the Pleistocene; it may have occurred as far south as Java in the middle to Late Pleistocene. Fossils also known from the Middle Pleistocene of Thailand along with Stegodon, gaur, wild water buffalo, and other living and extinct mammals. Today, it has been elim... | Sun bear | Wikipedia | 175 | 563137 | https://en.wikipedia.org/wiki/Sun%20bear | Biology and health sciences | Bears | Animals | vital_articles |
According to the IUCN Bear Specialist Group, sun bear populations have fallen by an estimated 35% since the 1990s. Numbers are especially low in Bangladesh and China, and populations in Vietnam are feared to decline severely by 50–80% in the next 30 years. Habitat fragmentation is on the rise, particularly in Borneo, S... | Sun bear | Wikipedia | 289 | 563137 | https://en.wikipedia.org/wiki/Sun%20bear | Biology and health sciences | Bears | Animals | vital_articles |
During surveys in Kalimantan between 1994 and 1997, interviewees admitted to hunting sun bears and indicated that sun bear meat is eaten by indigenous people in several areas there. Studies have found evidence of pet trade and sale of sun bear parts such as gall bladders in traditional Chinese medicine (TCM) shops in S... | Sun bear | Wikipedia | 293 | 563137 | https://en.wikipedia.org/wiki/Sun%20bear | Biology and health sciences | Bears | Animals | vital_articles |
Conservation measures
The sun bear is listed as vulnerable on the IUCN Red List, and is included in CITES Appendix I. With the exception of Sarawak (Malaysia) and Cambodia, the sun bear is legally protected from hunting in its whole range. A 2014 report documented rampant poaching and trade in sun bear parts in Sarawa... | Sun bear | Wikipedia | 185 | 563137 | https://en.wikipedia.org/wiki/Sun%20bear | Biology and health sciences | Bears | Animals | vital_articles |
Membrane potential (also transmembrane potential or membrane voltage) is the difference in electric potential between the interior and the exterior of a biological cell. It equals the interior potential minus the exterior potential. This is the energy (i.e. work) per charge which is required to move a (very small) posi... | Membrane potential | Wikipedia | 488 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
In non-excitable cells, and in excitable cells in their baseline states, the membrane potential is held at a relatively stable value, called the resting potential. For neurons, resting potential is defined as ranging from –80 to –70 millivolts; that is, the interior of a cell has a negative baseline voltage of a bit le... | Membrane potential | Wikipedia | 504 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
The system as a whole is electro-neutral. The uncompensated positive charges outside the cell, and the uncompensated negative charges inside the cell, physically line up on the membrane surface and attract each other across the lipid bilayer. Thus, the membrane potential is physically located only in the immediate vici... | Membrane potential | Wikipedia | 451 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
The same principle applies to voltage in cell biology. In electrically active tissue, the potential difference between any two points can be measured by inserting an electrode at each point, for example one inside and one outside the cell, and connecting both electrodes to the leads of what is in essence a specialized ... | Membrane potential | Wikipedia | 436 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
Ions cross the cell membrane under two influences: diffusion and electric fields. A simple example wherein two solutions—A and B—are separated by a porous barrier illustrates that diffusion will ensure that they will eventually mix into equal solutions. This mixing occurs because of the difference in their concentratio... | Membrane potential | Wikipedia | 495 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
In electrical terminology, the plasma membrane functions as a combined resistor and capacitor. Resistance arises from the fact that the membrane impedes the movement of charges across it. Capacitance arises from the fact that the lipid bilayer is so thin that an accumulation of charged particles on one side gives rise ... | Membrane potential | Wikipedia | 499 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
Ion pumps are integral membrane proteins that carry out active transport, i.e., use cellular energy (ATP) to "pump" the ions against their concentration gradient. Such ion pumps take in ions from one side of the membrane (decreasing its concentration there) and release them on the other side (increasing its concentrati... | Membrane potential | Wikipedia | 457 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
Another functionally important ion pump is the sodium-calcium exchanger. This pump operates in a conceptually similar way to the sodium-potassium pump, except that in each cycle it exchanges three Na+ from the extracellular space for one Ca++ from the intracellular space. Because the net flow of charge is inward, this ... | Membrane potential | Wikipedia | 487 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
Ion channels can be classified by how they respond to their environment. For example, the ion channels involved in the action potential are voltage-sensitive channels; they open and close in response to the voltage across the membrane. Ligand-gated channels form another important class; these ion channels open and clos... | Membrane potential | Wikipedia | 510 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
One of the most important members of this group is a type of voltage-gated sodium channel that underlies action potentials—these are sometimes called Hodgkin-Huxley sodium channels because they were initially characterized by Alan Lloyd Hodgkin and Andrew Huxley in their Nobel Prize-winning studies of the physiology of... | Membrane potential | Wikipedia | 459 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
Even if two different ions have the same charge (i.e., K+ and Na+), they can still have very different equilibrium potentials, provided their outside and/or inside concentrations differ. Take, for example, the equilibrium potentials of potassium and sodium in neurons. The potassium equilibrium potential EK is −84 mV wi... | Membrane potential | Wikipedia | 315 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
The most important regulators of cell excitability are the extracellular electrolyte concentrations (i.e. Na+, K+, Ca2+, Cl−, Mg2+) and associated proteins. Important proteins that regulate cell excitability are voltage-gated ion channels, ion transporters (e.g. Na+/K+-ATPase, magnesium transporters, acid–base transpor... | Membrane potential | Wikipedia | 449 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
Electrophysiologists model the effects of ionic concentration differences, ion channels, and membrane capacitance in terms of an equivalent circuit, which is intended to represent the electrical properties of a small patch of membrane. The equivalent circuit consists of a capacitor in parallel with four pathways each ... | Membrane potential | Wikipedia | 395 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
Resting potential
When the membrane potential of a cell goes for a long period of time without changing significantly, it is referred to as a resting potential or resting voltage. This term is used for the membrane potential of non-excitable cells, but also for the membrane potential of excitable cells in the absence ... | Membrane potential | Wikipedia | 364 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
In essence, the Goldman formula expresses the membrane potential as a weighted average of the reversal potentials for the individual ion types, weighted by permeability. (Although the membrane potential changes about 100 mV during an action potential, the concentrations of ions inside and outside the cell do not change... | Membrane potential | Wikipedia | 419 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
On the other hand, the high resting potential in undifferentiated cells does not necessarily incur a high metabolic cost. This apparent paradox is resolved by examination of the origin of that resting potential. Little-differentiated cells are characterized by extremely high input resistance, which implies that few lea... | Membrane potential | Wikipedia | 488 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
Graded membrane potentials are particularly important in neurons, where they are produced by synapses—a temporary change in membrane potential produced by activation of a synapse by a single graded or action potential is called a postsynaptic potential. Neurotransmitters that act to open Na+ channels typically cause th... | Membrane potential | Wikipedia | 423 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
If the driving force is high, then the ion is being "pushed" across the membrane. If the permeability is high, it will be easier for the ion to diffuse across the membrane.
Driving force is the net electrical force available to move that ion across the membrane. It is calculated as the difference between the voltage... | Membrane potential | Wikipedia | 465 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
Effects and implications
While cells expend energy to transport ions and establish a transmembrane potential, they use this potential in turn to transport other ions and metabolites such as sugar. The transmembrane potential of the mitochondria drives the production of ATP, which is the common currency of biological en... | Membrane potential | Wikipedia | 235 | 563161 | https://en.wikipedia.org/wiki/Membrane%20potential | Biology and health sciences | Cell parts | Biology | vital_articles |
Adansonia is a genus made up of eight species of medium-to-large deciduous trees known as baobabs ( or ) or adansonias. They are placed in the family Malvaceae, subfamily Bombacoideae. They are native to Madagascar, mainland Africa, and Australia. The trees have also been introduced to other regions such as Asia. A ge... | Adansonia | Wikipedia | 512 | 563290 | https://en.wikipedia.org/wiki/Adansonia | Biology and health sciences | Others | null | vital_articles |
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