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Topic Review
Pseudomonas aeruginosa
Pseudomonas aeruginosa is the most frequent cause of infection among non-fermenting Gram-negative bacteria, predominantly affecting immunocompromised patients, but its pathogenic role should not be disregarded in immunocompetent patients. seudomonas aeruginosa is the most frequent cause of infection among non-fermenting Gram-negative bacteria, predominantly affecting immunocompromised patients, but its pathogenic role should not be disregarded in immunocompetent patients.
  • 3.9K
  • 21 Jan 2021
Topic Review
3D Braiding Technology
3D braiding technologies enable the production of structures with complex geometry, which are often used for lightweight solutions, for example in automotive engineering. In addition, medical technology offers wide-ranging applications for 3D braiding technology. 3D braided structures are defined as those with yarns that intersect in all three spatial directions. 3D braiding processes allow the fiber orientation to be easily influenced, thus ensuring high strength and stiffness with reduced mass.
  • 3.9K
  • 25 Aug 2021
Topic Review
Marine Mammal
Marine mammals are aquatic mammals that rely on the ocean and other marine ecosystems for their existence. They include animals such as seals, whales, manatees, sea otters and polar bears. They do not represent a distinct taxon or systematic grouping, but rather have a polyphyletic relation due to convergent evolution, as in they do not have an immediate common ancestor. They are also unified by their reliance on the marine environment for feeding. Marine mammal adaptation to an aquatic lifestyle varies considerably between species. Both cetaceans and sirenians are fully aquatic and therefore are obligate water dwellers. Seals and sea-lions are semiaquatic; they spend the majority of their time in the water, but need to return to land for important activities such as mating, breeding and molting. In contrast, both otters and the polar bear are much less adapted to aquatic living. Their diet varies considerably as well; some may eat zooplankton, others may eat fish, squid, shellfish, sea-grass and a few may eat other mammals. While the number of marine mammals is small compared to those found on land, their roles in various ecosystems are large, especially concerning the maintenance of marine ecosystems, through processes including the regulation of prey populations. This role in maintaining ecosystems makes them of particular concern as 23% of marine mammal species are currently threatened. Marine mammals were first hunted by aboriginal peoples for food and other resources. Many were also the target for commercial industry, leading to a sharp decline in all populations of exploited species, such as whales and seals. Commercial hunting lead to the extinction of †Steller's sea cow, †sea mink, †Japanese sea lion and the †Caribbean monk seal. After commercial hunting ended, some species, such as the gray whale and northern elephant seal, have rebounded in numbers; conversely, other species, such as the North Atlantic right whale, are critically endangered. Other than hunting, marine mammals can be killed as bycatch from fisheries, where they become entangled in fixed netting and drown or starve. Increased ocean traffic causes collisions between fast ocean vessels and large marine mammals. Habitat degradation also threatens marine mammals and their ability to find and catch food. Noise pollution, for example, may adversely affect echolocating mammals, and the ongoing effects of global warming degrade arctic environments.
  • 3.9K
  • 21 Oct 2022
Topic Review
Greek Old Calendarists
Greek Old Calendarists (Greek: Παλαιοημερολογίτες, Paleoimerologites), sometimes abbreviated as GOC ("Genuine Orthodox Christians"), are groups of Old Calendarist Orthodox Christians that remained committed to the traditional Orthodox practice and are not in communion with many other Orthodox churches such as the Orthodox Church of Greece, the Patriarchate of Constantinople, or the Church of Cyprus. The split began with a disagreement over the abandonment of the traditional church calendar (also called the Julian calendar) in preference to the adoption of the Revised Julian calendar which is similar to the papal Gregorian calendar but will pull ahead by one day in the year 2800 and over other liturgical reforms that were introduced.
  • 3.9K
  • 24 Nov 2022
Topic Review
Coenzyme A
Coenzyme A (CoA) is synthetized from pantothenic acid (commonly known as vitamin B5). The importance of CoA as a carrier of acyl residues in cell metabolism is well understood. Coenzyme A participates in more than 100 different catabolic and anabolic reactions, including those involved in the metabolism of lipids, carbohydrates, proteins, ethanol, bile acids, and xenobiotics.
  • 3.9K
  • 15 Dec 2020
Topic Review
Wearable User Interface
Making a wearable robot is one of the most important research issues, not only in the bio-mimicking robotics area but also in the conventional robotics or haptics area. There are many advantages for using DEAs for wearable interfaces, such as their small size, flexibility, softness, and customizability. Many wearable haptic interfaces using Dielectric Elastomer Actuators such as tactile displays or vibrotactile displays were suggested from the previous researches. However, there are several challenges in the use of DEAs as actuators embedded into wearable devices such as high driving voltage and low output force compare to the motor based actuator. 
  • 3.9K
  • 01 Nov 2020
Topic Review
Naturally Occurring Hydroxycinnamic Acids
Naturally occurring hydroxycinnamic acids, namely ferulic, para-coumaric, caffeic, sinapic acids, and 3,4-dimethoxycinnamic acid are present in significant quantities in the cell wall of plants. They can make up about a third of the phenolic compounds in our diet, hence the interest in their potential biological activity and properties. Methods of synthesis and properties of natural and synthetic hydroxycinnamic acid derivatives are reviewed in detail.
  • 3.9K
  • 10 Nov 2020
Topic Review
Meaning
In semantics, semiotics, philosophy of language, metaphysics, and metasemantics, meaning "is a relationship between two sorts of things: signs and the kinds of things they intend, express, or signify". The types of meanings vary according to the types of the thing that is being represented. Namely: The major contemporary positions of meaning come under the following partial definitions of meaning:
  • 3.9K
  • 09 Oct 2022
Topic Review
Ischemic Stroke Pathophysiology and Preclinical Models
Ischemic stroke is a leading cause of death worldwide, mainly in western countries. So far, approved therapies rely mainly on reperfusion of the affected brain area, by intravenous thrombolysis or mechanical thrombectomy. The combination of pharmacological brain-protective strategies with reperfusion is the future of stroke therapy, aiming to reduce brain cell death and decrease patients’ disabilities. The success of new therapies relies on bringing preclinical studies and clinical practice close together. Recent upgrades of in vitro and in vivo stroke models for accurate and effective evaluation of therapeutic strategies are described.
  • 3.9K
  • 20 Oct 2022
Topic Review Peer Reviewed
Aircraft Icing Severity Evaluation
Aircraft icing refers to the ice buildup on the surface of an aircraft flying in icing conditions. The ice accretion on the aircraft alters the original aerodynamic configuration and degrades the aerodynamic performances and may lead to unsafe flight conditions. Evaluating the flow structure, icing mechanism and consequences is of great importance to the development of an anti/deicing technique. Studies have shown computational fluid dynamics (CFD) and machine learning (ML) to be effective in predicting the ice shape and icing severity under different flight conditions. CFD solves a set of partial differential equations to obtain the air flow fields, water droplets trajectories and ice shape. ML is a branch of artificial intelligence and, based on the data, the self-improved computer algorithms can be effective in finding the nonlinear mapping relationship between the input flight conditions and the output aircraft icing severity features.
  • 3.9K
  • 13 Apr 2022
Topic Review
Applications of VR
Applications of VR (also known as virtual reality) can be found in fields as diverse as entertainment, marketing, education, medicine, and many others. They provide numerous possibilities for users to explore virtual realities for various purposes.
  • 3.9K
  • 01 Dec 2022
Topic Review
Market Power
In economics, market power refers to the ability of a firm to influence the price at which it sells a product or service to increase economic profit. In other words, market power occurs if a firm does not face a perfectly elastic demand curve and can set its price (P) above marginal cost (MC) without losing sales. This indicates that the magnitude of market power is associated with the gap between P and MC at a firm's profit maximising level of output. Such propensities contradict perfectly competitive markets, where market participants have no market power, P = MC and firms earn zero economic profit. Market participants in perfectly competitive markets are consequently referred to as 'price takers', whereas market participants that exhibit market power are referred to as 'price makers' or 'price setters'. A firm with market power has the ability to individually affect either the total quantity or price in the market. This said, market power has been seen to exert more upward pressure on prices due to effects relating to Nash equilibria and profitable deviations that can be made by raising prices. Price makers face a downward-sloping demand curve and as a result, price increases lead to a lower quantity demanded. The decrease in supply creates an economic deadweight loss (DWL) and a decline in consumer surplus. This is viewed as socially undesirable and has implications for welfare and resource allocation as larger firms with high markups negatively effect labour markets by providing lower wages. Perfectly competitive markets do not exhibit such issues as firms set prices that reflect costs, which is to the benefit of the customer. As a result, many countries have antitrust or other legislation intended to limit the ability of firms to accrue market power. Such legislation often regulates mergers and sometimes introduces a judicial power to compel divestiture. Market power provides firms with the ability to engage in unilateral anti-competitive behavior. As a result, legislation recognises that firms with market power can, in some circumstances, damage the competitive process. In particular, firms with market power are accused of limit pricing, predatory pricing, holding excess capacity and strategic bundling. A firm usually has market power by having a high market share although this alone is not sufficient to establish the possession of significant market power. This is because highly concentrated markets may be contestable if there are no barriers to entry or exit. Invariably, this limits the incumbent firm's ability to raise its price above competitive levels. If no individual participant in the market has significant market power, anti-competitive conduct can only take place through collusion, or the exercise of a group of participants' collective market power. An example of which was seen in 2007, when British Airways was found to have colluded with Virgin Atlantic between 2004 and 2006, increasing their surcharges per ticket from £5 to £60. Regulators are able to assess the level of market power and dominance a firm has and measure competition through the use of several tools and indicators. Although market power is extremely difficult to measure, through the use of widely used analytical techniques such as concentration ratios, the Herfindahl-Hirschman index and the Lerner index, regulators are able to oversee and attempt to restore market competitiveness.
  • 3.9K
  • 19 Oct 2022
Topic Review
Subscriber Identity Module
A subscriber identity module or subscriber identification module (SIM), widely known as a SIM card, is an integrated circuit that is intended to securely store the international mobile subscriber identity (IMSI) number and its related key, which are used to identify and authenticate subscribers on mobile telephony devices (such as mobile phones and computers). It is also possible to store contact information on many SIM cards. SIM cards are always used on GSM phones; for CDMA phones, they are only needed for newer LTE-capable handsets. SIM cards can also be used in satellite phones, smart watches, computers, or cameras. The SIM circuit is part of the function of a universal integrated circuit card (UICC) physical smart card, which is usually made of PVC with embedded contacts and semiconductors. SIM cards are transferable between different mobile devices. The first UICC smart cards were the size of credit and bank cards; sizes were reduced several times over the years, usually keeping electrical contacts the same, so that a larger card could be cut down to a smaller size. A SIM card contains its unique serial number (ICCID), international mobile subscriber identity (IMSI) number, security authentication and ciphering information, temporary information related to the local network, a list of the services the user has access to, and two passwords: a personal identification number (PIN) for ordinary use, and a personal unblocking code (PUC) for PIN unlocking.
  • 3.9K
  • 25 Oct 2022
Topic Review
Social Media
Social media is a computer-based technology that facilitates the sharing of ideas, thoughts, and information through the building of virtual networks and communities.
  • 3.9K
  • 14 Oct 2021
Topic Review
Interferometric Fiber Optic Sensors
Due to the improvement of living standards, people’s attention to health has gradually increased. More and more people are willing to spend money and time on health management. The vital signs monitoring system based on fiber optic interferometers, including the design of sensor structures, signal demodulation methods and data analysis. After a large number of trials, the system can achieve long-term stable heart rate (HR), respiration rate (RR) and body temperature monitoring, and the collected data can be used for health analysis. Due to the high sensitivity, low cost, and light weight of the interferometric fiber optic sensor, it can be integrated under a mattress or a cushion, which is very suitable for daily use. The system has great application prospects in the field of healthcare. 
  • 3.9K
  • 26 Jan 2022
Topic Review
The All
The All (also called The One, The Absolute, The Great One, The Creator, The Supreme Mind, The Supreme Good, The Father, and The All Mother) is the Hermetic, pantheistic, pandeistic or panentheistic (and thus also panpsychism/monopsychism/unus mundus/anima mundi) view of God, which is that everything that is, or at least that can be experienced, collectively makes up The All. One Hermetic maxim states, "While All is in The All, it is equally true that The All is in All." The All can also be seen to be androgynous, possessing both masculine and feminine qualities in equal part.
  • 3.9K
  • 18 Oct 2022
Topic Review
Capital Centre
The Capital Centre (later USAir Arena and US Airways Arena) was an indoor arena in the eastern United States, located in Landover, Maryland, east of Washington, D.C. Opened in late 1973, it closed in 1999, and was demolished in 2002. The seating capacity was 18,756 for basketball and 18,130 for hockey. The elevation at street level was approximately 160 feet (50 m) above sea level. The U.S. Census Bureau defined the land, later occupied by The Boulevard at the Capital Centre, as being in the Mitchellville census-designated place as of the 1990 U.S. Census, while in the 2000 U.S. Census the area was placed in the Lake Arbor CDP.
  • 3.9K
  • 28 Nov 2022
Topic Review
Reactive Oxygen Species in Macrophages
Reactive oxygen species (ROS) are a chemically defined group of reactive molecules derived from molecular oxygen. ROS are involved in a plethora of processes in cells in all domains of life, ranging from bacteria, plants and animals, including humans. The importance of ROS for macrophage-mediated immunity is unquestioned. Their functions comprise direct antimicrobial activity against bacteria and parasites as well as redox-regulation of immune signaling and induction of inflammasome activation.
  • 3.9K
  • 10 May 2021
Topic Review
Stellar Aberration (Derivation from Lorentz Transformation)
Stellar aberration is an astronomical phenomenon "which produces an apparent motion of celestial objects". It can be proven mathematically that stellar aberration is due to the change of the astronomer's inertial frame of reference. The formula is derived with the use of Lorentz transformation of the star's coordinates. As the astronomer John Herschel has already explained in 1844, the stellar aberration does not depend on the relative velocity of the star towards Earth. Otherwise eclipsing binary stars would appear to be separated, in stark contrast to observation: both stars are rotating with high speed —and ever changing and different velocity vectors— around each other, but they appear as one spot all the time.
  • 3.9K
  • 27 Oct 2022
Topic Review
Geology of the Himalaya
The geology of the Himalayas is a record of the most dramatic and visible creations of the immense mountain range formed by plate tectonic forces and sculpted by weathering and erosion. The Himalayas, which stretch over 2400 km between the Namcha Barwa syntaxis at the eastern end of the mountain range and the Nanga Parbat syntaxis at the western end, are the result of an ongoing orogeny — the collision of the continental crust of two tectonic plates, namely, the Indian Plate thrusting into the Eurasian Plate. The Himalaya-Tibet region supplies fresh water for more than one-fifth of the world population, and accounts for a quarter of the global sedimentary budget. Topographically, the belt has many superlatives: the highest rate of uplift (nearly 10 mm/year at Nanga Parbat), the highest relief (8848 m at Mt. Everest Chomolangma), among the highest erosion rates at 2–12 mm/yr, the source of some of the greatest rivers and the highest concentration of glaciers outside of the polar regions. This last feature earned the Himalaya its name, originating from the Sanskrit for "the abode of the snow". From south to north the Himalaya (Himalaya orogen) is divided into 4 parallel tectonostratigraphic zones and 5 thrust faults which extend across the length of Himalaya orogen. Each zone, flanked by the thrust faults on its north and south, has stratigraphy (type of rocks and their layering) different from the adjacent zones. From south to north, the zones and the major faults separating them are the Main Frontal Thrust (MFT), Subhimalaya Zone (also called Sivalik), Main Boundary Thrust (MBT), Lesser Himalaya (further subdivided into the "Lesser Himalayan Sedimentary Zone (LHSZ) and the Lesser Himalayan Crystalline Nappes (LHCN)), Main Central thrust (MCT), Higher (or Greater) Himalayan crystallines (HHC), South Tibetan detachment system (STD), Tethys Himalaya (TH), and the Indus‐Tsangpo Suture Zone (ISZ). North of this lies the transhimalaya in Tibet which is outside the Himalayas. Himalaya has Indo-Gangetic Plain in south, Pamir Mountains in west in Central Asia, and Hengduan Mountains in east on China–Myanmar border. From east to west the Himalayas are divided into 3 regions, Eastern Himalaya, Central Himalaya, and Western Himalaya, which collectively house several nations and states.
  • 3.9K
  • 05 Dec 2022
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