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Topic Review
IgG Transplacental Transfer: Benefits & Risks
IgG antibodies can cross and do cross the placenta during pregnancy from the mother to the fetus. The passage starts by the end of the first trimester and continues throughout pregnancy. This is a manner by which the fetus gets passive humoral immunity from the mother. In the early neonatal period, these transferred maternal antibodies will act as a defense and help the developing immunity of the baby. While they are short-lived and cleared from the neonatal circulation within several months, they may be very helpful. A down-side is that in certain maternal autoimmune conditions auto-antibodies seem to have the capacity to hijack the transfer mechanism. It is the case for anti-Ro antibodies. These antibodies are frequent in women with systemic lupus erythematosus and/or Sjogren syndrome. They can lead to fetal atrioventricular block.   
  • 5.9K
  • 17 Jan 2022
Topic Review
Transmission (Mechanics)
A transmission is a machine in a power transmission system, which provides controlled application of power. Often the term 5-speed transmission refers simply to the gearbox, that uses gears and gear trains to provide speed and torque block conversions from a rotating power source to another device. The term transmission properly refers to the whole drivetrain, including clutch, gearbox, prop shaft (for rear-wheel drive vehicles), differential, and final drive shafts. In the United States the term is sometimes used in casual speech to refer more specifically to the gearbox alone, and detailed usage differs. The most common use is in motor vehicles, where the transmission adapts the output of the internal combustion engine to the drive wheels. Such engines need to operate at a relatively high rotational speed, which is inappropriate for starting, stopping, and slower travel. The transmission reduces the higher engine speed to the slower wheel speed, increasing torque in the process. Transmissions are also used on pedal bicycles, fixed machines, and where different rotational speeds and torques are adapted. Often, a transmission has multiple gear ratios (or simply "gears") with the ability to switch between them as the speed varies. This switching may be done manually (by the operator) or automatically (by a control unit). Directional (forward and reverse) control may also be provided. Single-ratio transmissions also exist, which simply change the speed and torque (and sometimes direction) of motor output. In motor vehicles, the transmission generally is connected to the engine crankshaft via a flywheel or clutch or fluid coupling, partly because internal combustion engines cannot run below a particular speed. The output of the transmission is transmitted via the driveshaft to one or more differentials, which drive the wheels. While a differential may also provide gear reduction, its primary purpose is to permit the wheels at either end of an axle to rotate at different speeds (essential to avoid wheel slippage on turns) as it changes the direction of rotation. Conventional gear/belt transmissions are not the only mechanism for speed/torque adaptation. Alternative mechanisms include torque converters and power transformation (e.g. diesel-electric transmission and hydraulic drive system). Hybrid configurations also exist. Automatic transmissions use a valve body to shift gears using fluid pressures in response to engine RPM, speed, and throttle input.
  • 5.9K
  • 01 Nov 2022
Topic Review
Distance Measures (Cosmology)
Distance measures are used in physical cosmology to give a natural notion of the distance between two objects or events in the universe. They are often used to tie some observable quantity (such as the luminosity of a distant quasar, the redshift of a distant galaxy, or the angular size of the acoustic peaks in the cosmic microwave background (CMB) power spectrum) to another quantity that is not directly observable, but is more convenient for calculations (such as the comoving coordinates of the quasar, galaxy, etc.). The distance measures discussed here all reduce to the common notion of Euclidean distance at low redshift. In accord with our present understanding of cosmology, these measures are calculated within the context of general relativity, where the Friedmann–Lemaître–Robertson–Walker solution is used to describe the universe.
  • 5.9K
  • 19 Oct 2022
Topic Review
Carcharodontosaurus
Carcharodontosaurus (/ˌkɑːrkəroʊˌdɒntoʊˈsɔːrəs/; lit. sharp-toothed lizard) is a genus of large carcharodontosaurid theropod dinosaur that existed during the Cenomanian age of the Late Cretaceous in Northern Africa. The genus Carcharodontosaurus is named after the shark genus Carcharodon, itself composed of the Greek karchar[os] (κάρχαρος, meaning "jagged" or "sharp") and odōn (ὀδών, "teeth"), and the suffix -saurus ("lizard"). It is currently known to have two species: C. saharicus and C. iguidensis.
  • 5.9K
  • 09 Nov 2022
Topic Review Peer Reviewed
Entropy
The concept of entropy constitutes, together with energy, a cornerstone of contemporary physics and related areas. It was originally introduced by Clausius in 1865 along abstract lines focusing on thermodynamical irreversibility of macroscopic physical processes. In the next decade, Boltzmann made the genius connection—further developed by Gibbs—of the entropy with the microscopic world, which led to the formulation of a new and impressively successful physical theory, thereafter named statistical mechanics. The extension to quantum mechanical systems was formalized by von Neumann in 1927, and the connections with the theory of communications and, more widely, with the theory of information were respectively introduced by Shannon in 1948 and Jaynes in 1957. Since then, over fifty new entropic functionals emerged in the scientific and technological literature. The most popular among them are the additive Renyi one introduced in 1961, and the nonadditive one introduced in 1988 as a basis for the generalization of the Boltzmann–Gibbs and related equilibrium and nonequilibrium theories, focusing on natural, artificial and social complex systems. Along such lines, theoretical, experimental, observational and computational efforts, and their connections to nonlinear dynamical systems and the theory of probabilities, are currently under progress. Illustrative applications, in physics and elsewhere, of these recent developments are briefly described in the present synopsis.
  • 5.9K
  • 07 May 2022
Topic Review
Disse (Space of Disse)
Space of Disse: a thin perisinusoidal area between the endothelial cells and hepatocytes filled with blood plasma, nutrients and oxygen, but also debris from our organism, that have acquired great importance in liver disease
  • 5.9K
  • 20 Feb 2021
Topic Review
Marine Battery Energy Storage Systems on Ships
The shipping industry is going through a period of technology transition that aims to increase the use of carbon-neutral fuels. There is a significant trend of vessels being ordered with alternative fuel propulsion. Shipping’s future fuel market will be more diverse, reliant on multiple energy sources. One of very promising means to meet the decarbonisation requirements is to operate ships with sustainable electrical energy by integrating local renewables, shore connection systems and battery energy storage systems (BESS). 
  • 5.9K
  • 20 Mar 2023
Topic Review
Unintended Consequences
In the social sciences, unintended consequences (sometimes unanticipated consequences or unforeseen consequences) are outcomes of a purposeful action that are not intended or foreseen. The term was popularised in the twentieth century by American sociologist Robert K. Merton and expanded by economist Thomas Sowell and psychologist Stuart Vyse. Unintended consequences can be grouped into three types: Unexpected benefit: A positive unexpected benefit (also referred to as luck, serendipity or a windfall). Unexpected drawback: An unexpected detriment occurring in addition to the desired effect of the policy (e.g., while irrigation schemes provide people with water for agriculture, they can increase waterborne diseases that have devastating health effects, such as schistosomiasis). Perverse result: A perverse effect contrary to what was originally intended (when an intended solution makes a problem worse).
  • 5.9K
  • 14 Oct 2022
Topic Review
DRDO Rustom
The DRDO Rustom (English: Warrior) is a Medium Altitude Long Endurance unmanned air vehicle (UAV) being developed by Defence Research and Development Organisation for the three services, Indian Army, Indian Navy and the Indian Air Force of the Indian Armed Forces. Rustom is derived from the NAL's LCRA (Light Canard Research Aircraft) developed by a team under the leadership of late Prof Rustom Damania in the 1980s. The UAV will have structural changes and a new engine. Rustom will replace/supplement the Heron UAVs in service with the Indian armed forces.
  • 5.9K
  • 02 Nov 2022
Topic Review
Bongo Drum
Bongos (Spanish: bongó) are an Afro-Cuban percussion instrument consisting of a pair of small open bottomed hand drums of different sizes. They are struck with both hands, most commonly in an eight-stroke pattern called martillo (hammer). They are mainly employed in the rhythm section of son cubano and salsa ensembles, often alongside other drums such as the larger congas and the stick-struck timbales. Bongo drummers (bongoseros) emerged as the only drummers of son cubano ensembles in eastern Cuba toward the end of the 19th century. The instrument remained important as son groups evolved into larger conjuntos and orchestras in Havana in the 1940s, at which point they began to share the stage with congas. Bongos later reached the United States, where they are commonly played in salsa, Afro-Cuban jazz, Latin rock and other genres. Bongo drums are about 20 centimetres (8 in) high and have diameters of approximately 20 centimetres (8 in) and 25 centimetres (10 in) (the smaller drum is called macho, male, and the larger drum, hembra, female). They are the smallest drums in Latin percussion, some models being only 15 centimetres (6 in) in diameter. The shells of the drums and the bridge (the small block that joins them) are usually made of wood, although fiberglass is also common. The heads are typically made of calfskin and attached to the shells via steel hardware that enables their tuning. Originally, metal tacks were used, so tuning had to be done by heating the skins.
  • 5.9K
  • 02 Nov 2022
Topic Review
Saltation
In biology, saltation (from la saltus 'leap, jump') is a sudden and large mutational change from one generation to the next, potentially causing single-step speciation. This was historically offered as an alternative to Darwinism. Some forms of mutationism were effectively saltationist, implying large discontinuous jumps. Speciation, such as by polyploidy in plants, can sometimes be achieved in a single and in evolutionary terms sudden step. Evidence exists for various forms of saltation in a variety of organisms.
  • 5.9K
  • 29 Sep 2022
Topic Review
Mechanisms of Essential oils on Central Nervous System
Essential oils (EOs) are naturally occurring complex mixtures of volatile odor compounds synthesized as secondary metabolites by plants and are extracted through steam distillation, solvent extraction, maceration, cold press extraction, water distillation, and CO2 extraction. Novel methods that are more efficient and provide higher yields include supercritical fluid extraction, microwave-assisted extraction, and ultrasound. Studies conducted on animals and humans have shown that EOs can produce a variety of central nervous system (CNS) targeted pharmacological effects such as anxiolytic effect, neuroprotection, antidepressant effect, anticonvulsant effect, analgesic, and sedative effect, to name a few. As a result, EOs can be used as an adjuvant therapy to prevent and relieve symptoms associated with CNS-based disorders such as insomnia, depression, dementia, Alzheimer’s disease (AD), etc.
  • 5.9K
  • 10 Feb 2022
Topic Review
Public Parks
Public parks are a part of the public spaces of a city. Cities are rediscovering the potential of urban parks to advance environmental sustainability and enhance its social amenities.
  • 5.9K
  • 16 Jan 2022
Topic Review
Egyptian Medical Papyri
Egyptian medical papyri are ancient Egyptian texts written on papyrus which permit a glimpse at medical procedures and practices in ancient Egypt. The papyri give details on disease, diagnosis, and remedies of disease, which include herbal remedies, surgery, and magical spells. It is thought there were more medical papyri, but many have been lost due to grave robbing. The largest study of the medical papyri to date has been undertaken by Humboldt University of Berlin and was titled Medizin der alten Ägypter ("Medicine of ancient Egypt"). Early Egyptian medicine was based mostly on a mixture of magic and religious spells. Most commonly "cured" by use of amulets or magical spells, the illnesses were thought to be caused by spiteful behavior or actions. Afterwards, doctors performed various medical treatments if necessary. The instructions for these medical rituals were later inscribed on papyrus scrolls by the priests performing the actions.
  • 5.9K
  • 07 Nov 2022
Topic Review
Mortal Kombat
Mortal Kombat is an American media franchise centered on a series of video games, originally developed by Midway Games in 1992. The development of the first game was originally based on an idea that Ed Boon and John Tobias had of making a video game starring Jean-Claude Van Damme, but as that idea fell through, a fantasy-themed fighting game was created instead, nonetheless paying homage to him with nut-cracking movie star character Johnny Cage, whose initials and personal style echo Van Damme's. Mortal Kombat was the first ever fighting game to introduce a secret fighter, reached if the player fulfilled a set of requirements. The original game has spawned many sequels and spin-offs consisting of several action-adventure games, as well as a comic book series and a card game. Film producer Lawrence Kasanoff licensed the rights to the game in the early 1990s and produced the first hit movie ever made from a video game. Lawrence also produced the second movie, animated TV series, live-action TV series films, the first one million platinum-selling album and a live-action tour. Mortal Kombat has become the most successful fighting franchise in the history of video games and one of the highest-grossing media franchises of all time. The series has a reputation for high levels of graphic violence, including, most notably, its Fatalities (finishing moves allowing the player to finish off their defeated opponent). Controversies surrounding Mortal Kombat, in part, led to the creation of the ESRB video game rating system. Early games in this series were also noted for their realistic digitized sprites and an extensive use of palette swapping to create new characters. Following Midway's bankruptcy, the Mortal Kombat development team was acquired by Warner Bros. Entertainment and turned into NetherRealm Studios.
  • 5.9K
  • 19 Oct 2022
Topic Review
Post-Translational Modification
Post-translational modifications (PTMs) add a layer of complexity to the proteome through the addition of biochemical moieties to specific residues of proteins, altering their structure, function and/or localization. Mass spectrometry (MS)-based techniques are at the forefront of PTM analysis due to their ability to detect large numbers of modified proteins with a high level of sensitivity and specificity.
  • 5.9K
  • 29 Apr 2021
Topic Review
Illegal IPTV Technologies
Technologies providing copyright-infringing IPTV content are commonly used as an illegal alternative to legal IPTV subscriptions and services, as they usually have lower monetary costs and can be more convenient for users who follow content from different sources. These infringing IPTV technologies may include websites, software, software add-ons, and physical set-top boxes. Due to the free or low cost of illegal IPTV technologies, illicit IPTV content providers will often resort to intrusive advertising, scams, and the distribution of malware to increase their revenue.
  • 5.9K
  • 20 Oct 2023
Topic Review
Sultan
Sultan (/ˈsʌltən/; Arabic: سلطان sulṭān, pronounced [sʊlˈtˤɑːn, solˈtˤɑːn]) is a position with several historical meanings. Originally, it was an Arabic abstract noun meaning "strength", "authority", "rulership", derived from the verbal noun سلطة sulṭah, meaning "authority" or "power". Later, it came to be used as the title of certain rulers who claimed almost full sovereignty in practical terms (i.e., the lack of dependence on any higher ruler), albeit without claiming the overall caliphate, or to refer to a powerful governor of a province within the caliphate. The adjectival form of the word is "sultanic", and the state and territories ruled by a sultan, as well as his office, are referred to as a sultanate (سلطنة salṭanah). The term is distinct from king (ملك malik), despite both referring to a sovereign ruler. The use of "sultan" is restricted to Muslim countries, where the title carries religious significance, contrasting the more secular king, which is used in both Muslim and non-Muslim countries. Brunei and Oman are the only independent countries which retain the title "sultan" for their monarchs. In recent years, the title has been gradually replaced by "king" by contemporary hereditary rulers who wish to emphasize their secular authority under the rule of law. A notable example is Morocco, whose monarch changed his title from sultan to king in 1957.
  • 5.9K
  • 23 Nov 2022
Topic Review Peer Reviewed
Non-Patent Literature
Non-patent literature is defined as scientific publications, technical standards, conference proceedings, clinical trials, books, manuals, technical or research reports, or any other technical scientific material which is cited in patents to show what has already been published and disseminated about the invention to be patented, in order to justify its novelty. These documents are considered technically relevant to the patent granting procedure and are cited along with other patents related to the same subject matter. 
  • 5.9K
  • 13 Apr 2022
Topic Review
Earthquake Early Warning Systems
An Earthquake Early Warning Systems (EEWS) is the combination of different elements, such as seismometers, sensors, communication appliances, computers, and alarm systems, able to detect and warm of the arrival of seismic waves. It serves to mitigate damages and losses , to be used primarily in moderate and high seismically active regions.  
  • 5.9K
  • 25 Feb 2021
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