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Topic Review
Universal Model of Cancer Transformation and Development
As a phenomenon, cancer is a disease related to multicellular evolution, i.e., cancer in general is understood to be a failure of the multicellular systems and is considered a reversal to unicellularity. Cancer cells are like unicellular organisms that benefit from ancestral-like traits. As a disease, cancer can be interpreted as (a) a destruction of cooperative behaviors underlying multicellular evolution, (b) a disruption of molecular networks established during the emergence of multicellularity or (c) an atavistic state resulting from reactivation of primitive programs typical of the earliest unicellular species. From this point of view and in accordance with the layered model of evolution of cellular functionalities, cancer transformation can occur as a result of huge disturbances or the destruction of functionalities that are located in the multicellular layer.
  • 5.4K
  • 06 May 2022
Topic Review
Japanese River Otter
The Japanese river otter (Japanese: ニホンカワウソ(日本川獺 ー, Hepburn: Nihon-kawauso) (Lutra lutra whiteleyi) is an extinct variety of otter formerly widespread in Japan. Dating back to the 1880s, it was even seen in Tokyo. The population suddenly shrank in the 1930s, and the mammal nearly vanished. Since then, it has only been spotted several times, in 1964 in the Seto Inland Sea, and in the Uwa Sea in 1972 and 1973. The last official sighting was in the southern part of Kōchi Prefecture in 1979, when it was photographed in the mouth of the Shinjo River in Susaki. It was subsequently classified as a "Critically Endangered" species on the Japanese Red List. On August 28, 2012, the Japanese river otter was officially declared extinct by the Ministry of the Environment. It is the official animal symbol of Ehime Prefecture. In February 2017, a wild otter was caught on camera on Tsushima Island, Nagasaki Prefecture. However, it is not known whether the observed otter was a Japanese river otter.
  • 5.3K
  • 18 Oct 2022
Topic Review
Cylinder Block
The cylinder block is an integrated structure comprising the cylinder(s) of a reciprocating engine and often some or all of their associated surrounding structures (coolant passages, intake and exhaust passages and ports, and crankcase). The term engine block is often used synonymously with "cylinder block" (although technically distinctions can be made between en bloc cylinders as a discrete unit versus engine block designs with yet more integration that comprise the crankcase as well). In the basic terms of machine elements, the various main parts of an engine (such as cylinder(s), cylinder head(s), coolant passages, intake and exhaust passages, and crankcase) are conceptually distinct, and these items can all be made as discrete pieces that are bolted together. Such construction was very widespread in the early decades of the commercialization of internal combustion engines (1880s to 1920s), and it is still sometimes used in certain applications where it remains advantageous (especially very large engines, but also some small engines). However, it is no longer the normal way of building most petrol engines and diesel engines, because for any given engine configuration, there are more efficient ways of designing for manufacture (and also for maintenance and repair). These generally involve integrating multiple machine elements into one discrete part, and doing the making (such as casting, stamping, and machining) for multiple elements in one setup with one machine coordinate system (of a machine tool or other piece of manufacturing machinery). This yields lower unit cost of production (and/or maintenance and repair). Today most engines for cars, trucks, buses, tractors, and so on are built with fairly highly integrated design, so the words "monobloc" and "en bloc" are seldom used in describing them; such construction is often implicit. Thus "engine block", "cylinder block", or simply "block" are the terms likely to be heard in the garage or on the street.
  • 5.3K
  • 28 Sep 2022
Topic Review
Vinca Leaves
Morphological and anatomical traits of the Vinca leaf were examined using microscopy techniques. Outdoor Vinca minor and V. herbacea plants and greenhouse cultivated V. major and V. major var. variegata plants had interspecific variations. All Vinca species leaves are hypostomatic. However, except for V. minor leaf, few stomata were also present on the upper epidermis. V. minor leaf had the highest stomatal index and V. major had the lowest, while the distribution of trichomes on the upper epidermis was species-specific. Differentiated palisade and spongy parenchyma tissues were present in all Vinca species’ leaves. However, V. minor and V. herbacea leaves had a more organized anatomical aspect, compared to V. major and V. major var. variegata leaves. Additionally, as a novelty, the cellular to intercellular space ratio of the Vinca leaf’s mesophyll was revealed herein with the help of computational analysis.
  • 5.3K
  • 06 Apr 2021
Topic Review
Observer Effect
In physics, the observer effect is the disturbance of an observed system by the act of observation. This is often the result of instruments that, by necessity, alter the state of what they measure in some manner. A common example is checking the pressure in an automobile tire; this is difficult to do without letting out some of the air, thus changing the pressure. Similarly, seeing non-luminous objects requires light hitting the object, and causing it to reflect that light. While the effects of observation are often negligible, the object still experiences a change. This effect can be found in many domains of physics, but can usually be reduced to insignificance by using different instruments or observation techniques. A notable example of the observer effect occurs in quantum mechanics, as demonstrated by the double-slit experiment. Physicists have found that observation of quantum phenomena can change the measured results of this experiment. Despite the "observer effect" in the double-slit experiment being caused by the presence of an electronic detector, the experiment's results have been misinterpreted by some to suggest that a conscious mind can directly affect reality. The need for the "observer" to be conscious is not supported by scientific research, and has been pointed out as a misconception rooted in a poor understanding of the quantum wave function ψ and the quantum measurement process.
  • 5.3K
  • 29 Nov 2022
Topic Review
Big Three TV Networks
In the United States , there are three major traditional commercial broadcast television networks - CBS (Columbia Broadcasting System), NBC (National Broadcasting Company), and ABC (American Broadcasting Company) - that due to their longevity and ratings success are referred to as the "Big Three", which dominated American television until the 1990s, and are still considered major U.S. broadcast companies.
  • 5.3K
  • 08 Oct 2022
Topic Review
Birth Certificate
A birth certificate is a vital record that documents the birth of a child. The term "birth certificate" can refer to either the original document certifying the circumstances of the birth or to a certified copy of or representation of the ensuing registration of that birth. Depending on the jurisdiction, a record of birth might or might not contain verification of the event by such as a midwife or doctor.
  • 5.3K
  • 08 Nov 2022
Topic Review
Altitude (Triangle)
In geometry, an altitude of a triangle is a line segment through a vertex and perpendicular to (i.e., forming a right angle with) a line containing the base (the side opposite the vertex). This line containing the opposite side is called the extended base of the altitude. The intersection of the extended base and the altitude is called the foot of the altitude. The length of the altitude, often simply called "the altitude", is the distance between the extended base and the vertex. The process of drawing the altitude from the vertex to the foot is known as dropping the altitude at that vertex. It is a special case of orthogonal projection. Altitudes can be used in the computation of the area of a triangle: one half of the product of an altitude's length and its base's length equals the triangle's area. Thus, the longest altitude is perpendicular to the shortest side of the triangle. The altitudes are also related to the sides of the triangle through the trigonometric functions. In an isosceles triangle (a triangle with two congruent sides), the altitude having the incongruent side as its base will have the midpoint of that side as its foot. Also the altitude having the incongruent side as its base will be the angle bisector of the vertex angle. It is common to mark the altitude with the letter h (as in height), often subscripted with the name of the side the altitude is drawn to. In a right triangle, the altitude drawn to the hypotenuse c divides the hypotenuse into two segments of lengths p and q. If we denote the length of the altitude by hc, we then have the relation For acute and right triangles the feet of the altitudes all fall on the triangle's sides (not extended). In an obtuse triangle (one with an obtuse angle), the foot of the altitude to the obtuse-angled vertex falls in the interior of the opposite side, but the feet of the altitudes to the acute-angled vertices fall on the opposite extended side, exterior to the triangle. This is illustrated in the adjacent diagram: in this obtuse triangle, an altitude dropped perpendicularly from the top vertex, which has an acute angle, intersects the extended horizontal side outside the triangle.
  • 5.3K
  • 25 Oct 2022
Topic Review
Pathophysiology-Based Traumatic Brain Injury
Traumatic brain injury (TBI) is a leading cause of disability and death among children and young adults, with an incidence of approximately 1.7 million per year in the USA, resulting in 52,000 deaths. Survivors of the initial impact must still contend with the consequences of trauma, as not all injury occurs at the time of impact. The primary injury results from forces applied to the head and involve direct structural damage to the brain. This triggers a cascade of events leading to neurological damage that evolves secondary injury. Several external brain insults, both intracranial and systemic, may complicate and worsen the secondary injury.
  • 5.3K
  • 07 Mar 2024
Topic Review
House of Tudor
The House of Tudor was an English royal house of Welsh origin, descended in the male line from the Tudors of Penmynydd. Tudor monarchs ruled the Kingdom of England and its realms, including their ancestral Wales and the Lordship of Ireland (later the Kingdom of Ireland) from 1485 until 1603, with five monarchs in that period. The Tudors succeeded the House of Plantagenet as rulers of the Kingdom of England, and were succeeded by the House of Stuart. The first Tudor monarch, Henry VII of England, descended through his mother from a legitimised branch of the English royal House of Lancaster. The Tudor family rose to power in the wake of the Wars of the Roses, which left the House of Lancaster, to which the Tudors were aligned, extinct. Henry Tudor was able to establish himself as a candidate not only for traditional Lancastrian supporters, but also for the discontented supporters of their rival House of York, and he rose to the throne by the right of conquest. His victory at the Battle of Bosworth Field was reinforced by his marriage to Elizabeth of York, daughter of Edward IV, symbolically uniting the former warring factions under a new dynasty. The Tudors extended their power beyond modern England, achieving the full union of England and the Principality of Wales in 1542 (Laws in Wales Acts 1535 and 1542), and successfully asserting English authority over the Kingdom of Ireland. They also maintained the nominal English claim to the Kingdom of France; although none of them made substance of it, Henry VIII fought wars with France trying to reclaim that title. After him, his daughter Mary I lost control of all territory in France permanently with the fall of Calais in 1558. In total, five Tudor monarchs ruled their domains for just over a century. Henry VIII was the only son of Henry VII to live to the age of maturity. Issues around the royal succession (including marriage and the succession rights of women) became major political themes during the Tudor era. The House of Stuart, descended from Henry VII's daughter Margaret, came to power in 1603 when Elizabeth I died and the Tudor line failed. For analysis of politics, diplomacy and social history, see Tudor period.
  • 5.3K
  • 11 Nov 2022
Topic Review
Phosphorus (Morning Star)
Phosphorus (Greek Φωσφόρος Phōsphoros) is the Morning Star, the planet Venus in its morning appearance. Φαοσφόρος (Phaosphoros) and Φαεσφόρος (Phaesphoros) are forms of the same name in some Greek dialects. This celestial object was named when stars and planets were not always distinguished with modern precision. Another Greek name for the Morning Star is Heosphoros (Greek Ἑωσφόρος Heōsphoros), meaning "Dawn-Bringer". The form Eosphorus is sometimes met in English, as if from Ἠωσφόρος (Ēōsphoros), which is not actually found in Greek literature, but would be the form that Ἑωσφόρος would have in some dialects. As an adjective, the Greek word φωσφόρος is applied in the sense of "light-bringing" to, for instance, the dawn, the god Dionysos, pine torches, the day; and in the sense of "torch-bearing" as an epithet of several god and goddesses, especially Hecate but also of Artemis/Diana and Hephaestus. The Latin word lucifer, corresponding to Greek φωσφόρος, was used as a name for the morning star and thus appeared in the Vulgate translation of the Hebrew word הֵילֵל (helel), meaning Venus as the brilliant, bright or shining one, in Isaiah 14:12, where the Septuagint Greek version uses, not φωσφόρος, but ἑωσφόρος. As a translation of the same Hebrew word the King James Version gave "Lucifer", a name often misunderstood as a reference to Satan. Modern translations of the same passage render the Hebrew word instead as "morning star", "daystar", "shining one" or "shining star". In Revelation 22:16, Jesus is referred to as the morning star, but not as lucifer in Latin, nor as φωσφόρος in the original Greek text, which instead has ὁ ἀστὴρ ὁ λαμπρὸς ὁ πρωϊνός (ho astēr ho lampros ho prōinos), literally: the star, the shining one, the dawn. In the Vulgate Latin text of 2 Peter 1:19 the word "lucifer" is used of the morning star in the phrase "until the day dawns and the morning star rises in your hearts", the corresponding Greek word being φωσφόρος.
  • 5.3K
  • 31 Oct 2022
Topic Review
Lane Detection and Tracking
Lane detection and tracking are the advanced key features of the advanced driver assistance system. Lane detection is the process of detecting white lines on the roads. Lane tracking is the process of assisting the vehicle to remain in the desired path, and it controls the motion model by using previously detected lane markers.
  • 5.3K
  • 25 Oct 2021
Topic Review
Olive Tree (Religious Movement)
Olive Tree is the most common English name of a new religious movement founded in South Korea by Park Tae Son (한국예박태선). The movement was originally known in Korea as Jesus Christ Congregation Revival Association of Korea (한국예수교전도관부흥협회) and later as The Church of Heavenly Father (Cheonbugyo, 천부교). In a revised 2009 version of his 1996 doctoral dissertation on the history of Korean Pentecostalism, pastor Young Hoon Lee called the Olive Tree “the fastest growing and largest of the Korean syncretistic religions during the 1950s and 1960s,” although he noted it had become “largely insignificant” by the end of the 20th century. The Olive Tree is regarded as a cult by mainline Christian denominations in Korea, and it has been argued that combating the Olive Tree was a main reason for the emergence of an organized anti-cult movement in South Korea.
  • 5.3K
  • 25 Nov 2022
Topic Review
Natural Preservatives for Fish
Fish is extremely perishable as a result of rapid microbial growth naturally present in fish or from contamination. Synthetic preservatives are widely used in fish storage to extend shelf life and maintain quality and safety. Natural preservatives from microorganisms, plants, and animals have been shown potential in replacing the chemical antimicrobials. Bacteriocins and organic acids from bacteria showed good antimicrobial activities against spoilage bacteria. Plant-derived antimicrobials could prolong fish shelf life and decrease lipid oxidation. Animal-derived antimicrobials also have good antimicrobial activities.
  • 5.3K
  • 25 Jun 2021
Topic Review
Serotonin
Serotonin (5-hydroxytryptamine, 5-HT) plays two important roles in humans—one central and the other peripheral—depending on the location of the 5-HT pools of on either side of the blood-brain barrier. In the central nervous system it acts as a neurotransmitter, controlling such brain functions as autonomic neural activity, stress response, body temperature, sleep, mood and appetite. This role is very important in intensive care, as in critically ill patients multiple serotoninergic agents like opioids, antiemetics and antidepressants are frequently used. High serotonin levels lead to altered mental status, deliria, rigidity and myoclonus, together recognized as serotonin syndrome. In its role as a peripheral hormone, serotonin is unique in controlling the functions of several organs. In the gastrointestinal tract it is important for regulating motor and secretory functions. Apart from intestinal motility, energy metabolism is regulated by both central and peripheral serotonin signaling. It also has fundamental effects on hemostasis, vascular tone, heart rate, respiratory drive, cell growth and immunity. Serotonin regulates almost all immune cells in response to inflammation, following the activation of platelets. 
  • 5.3K
  • 18 May 2021
Topic Review
Passive Constant Flow Regulators
Passive flow control regulators, also known as passive flow control or autoregulated or pressure-compensated valves, deliver, without external control and energy consumption, a constant flow rate regardless of pressure variations.
  • 5.3K
  • 22 Dec 2020
Topic Review
Tomato and Olive Oil in Prostate Health
Tomato, the fruit providing the most comprehensive complex of prostate-health-preserving micronutrients, has been shown to be superior to its single-nutrient counterparts in decreasing the incidence of age-related prostate diseases.
  • 5.3K
  • 30 Mar 2023
Topic Review
Principles of the Suzuki Coupling Reaction
The Suzuki coupling is a transition metal-catalyzed, cross-coupling carbon–carbon (C–C) bond forming reaction between organic boron compounds and organic halides. As an operationally simple and versatilely applicable procedure, the Suzuki coupling reaction has found immense applications in drug discovery and development in the pharmaceutical industry. 
  • 5.3K
  • 06 Jan 2023
Topic Review
WordNet
WordNet is a lexical database of semantic relations between words in more than 200 languages. WordNet links words into semantic relations including synonyms, hyponyms, and meronyms. The synonyms are grouped into synsets with short definitions and usage examples. WordNet can thus be seen as a combination and extension of a dictionary and thesaurus. While it is accessible to human users via a web browser, its primary use is in automatic text analysis and artificial intelligence applications. WordNet was first created in the English language and the English WordNet database and software tools have been released under a BSD style license and are freely available for download from that WordNet website.
  • 5.3K
  • 11 Nov 2022
Topic Review
Fatty Acid Synthase
Fatty acid synthase is a multi-enzyme protein that involves in fatty acid synthesis. It's main function is to synthesise palmitate, a 16-carbon long chain saturated fatty acid from acetyl-CoA and malonyl-CoA, in the presence of NADPH.
  • 5.3K
  • 01 Sep 2020
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