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Topic Review
OER Electrocatalysts
The oxygen evolution reaction (OER) is the efficiency-determining half-reaction process of high-demand, electricity-driven water splitting due to its sluggish four-electron transfer reaction. Tremendous effects on developing OER catalysts with high activity and strong acid-tolerance at high oxidation potentials have been made for proton-conducting polymer electrolyte membrane water electrolysis (PEMWE), which is one of the most promising future hydrogen-fuel-generating technologies. Electrochemical water splitting involves two heterogeneous multi-step half-reactions, which are referred to as the cathodic hydrogen evolution reaction (HER) and the anodic oxygen evolution reaction (OER). An important frontier in OER electrocatalysis research is the development of the rational design of catalysts. Most of the excellent OER catalysts with high activity and durability are not stable in acidic solutions. They are easily oxidized and decomposed in a strong acid system, which is one of the indispensable working conditions for PEMWE.  Outstanding OER electrocatalysts should have excellent intrinsic activity and sufficient active sites, and these requirements are generally combined with simplicity and controllability.
  • 4.2K
  • 23 Jun 2021
Topic Review
Microgrid Control
Microgrids (MGs) are advancing in terms of intelligence, distribution, and flexibility. Electrical grids are being dominated by cutting-edge power electronics and artificial intelligence (AI) techniques, and this trend may continue for many years to come.
  • 4.2K
  • 21 Feb 2023
Topic Review
Social Trap
In psychology, a social trap is a conflict of interest or perverse incentive where individuals or a group of people act to obtain short-term individual gains, which in the long run leads to a loss for the group as a whole. Social traps are the cause of countless environmental issues, including overfishing, energy "brownout" and "blackout" power outages during periods of extreme temperatures, the overgrazing of cattle on the Sahelian Desert, the destruction of the rainforest by logging interests and agriculture, and, most importantly, climate change.
  • 4.1K
  • 01 Dec 2022
Topic Review
Medicinal Value of Dandelion
The genus Taraxacum is part of the Asteraceae family of the Cichorioideae subfamily, Lactuceae tribe. This plant's geographical distribution is usually around the warm areas of the Northern Hemisphere and its users have been cherishing it for its curative properties since ancient times. Reports show that traditional medicine practitioners used Taraxacum officinale L. for treating dyspepsia, spleen, liver disorders, hepatitis, and anorexia. Aqueous extracts of dandelion were also used traditionally through Asia, Europe, and North America for treating different types of cancer like leukemia and breast cancer, even if their working mechanisms were unknown. The main reported components of dandelions consist of phenolic acids (chicoric, caffeic, and chlorogenic acids), terpenes (taraxacoside, ainslioside, taraxinic acid), and storage carbohydrates (inulin), which are thought to be accountable for the plant’s health-related properties. This entry is based on a literature review and highlights the beneficial and therapeutic action of dandelion extracts and their confirmed or hypothesized mechanism of action in diabetes, hepatic disorders, and cardiovascular disease, as indicated by the results of in vivo an in vitro studies, on cell lines, human and animal models.
  • 4.1K
  • 10 May 2021
Topic Review
MIT License
The MIT License is a permissive free software license originating at the Massachusetts Institute of Technology (MIT) in the late 1980s. As a permissive license, it puts only very limited restriction on reuse and has, therefore, high license compatibility. The MIT License is compatible with many copyleft licenses, such as the GNU General Public License (GNU GPL). Any software licensed under the terms of the MIT License can be integrated with software licensed under the terms of the GNU GPL. Unlike copyleft software licenses, the MIT License also permits reuse within proprietary software, provided that all copies of the software or its substantial portions include a copy of the terms of the MIT License and also a copyright notice. (As of 2020), the MIT License was the most popular software license found in one analysis, continuing from reports in 2015 that the MIT License was the most popular software license on GitHub. Notable projects that use the MIT License include the X Window System, Ruby on Rails, Nim, Node.js, Lua, and jQuery. Notable companies using the MIT License include Microsoft (.NET Core), Google (Angular), and Meta (React).
  • 4.1K
  • 29 Nov 2022
Topic Review
Definitions and the Basics of Knot Tying
Surgical knots are sequences of half-knots (H) or half-hitches (S), defined by their number of throws, by an opposite or similar rotation compared with the previous one, and for half-hitches whether they are sliding (s) or blocking (b). Opposite rotation results in (more secure) symmetric (s) knots, similar rotation in asymmetric (a) knots, and changing the active and passive ends has the same effect as changing the rotation. Loop security is the force to keep tissue together after a first half-knot or sliding half-hitches. With polyfilament sutures, H2, H3, SSs, and SSsSsSs have a loop security of 10, 18, 28, and 48 Newton (N), respectively. With monofilament sutures, they are only 7, 16, 18, and 25 N. For knot security, half hitch sequences such as 2 sliding and 2 blocking half hitches are the future: the risk of destabilisation is less, and for monofilament sutures, they are mandatory.   
  • 4.1K
  • 05 Dec 2023
Topic Review
Promoting Traditional Craftsmanship Through Digital Technology
Τhe success of assisting Cultural Heritage (CH) valorization through digital technologies (availability, accessibility, and engaging and interactive presentations) is due to the captivating content of stories, memories, and meaning that CH offers. Traditional Crafts (TCs) have a paramount cultural value and offer a thematic thesaurus of stories and narratives related to the origins of modern societies, history, and culture, the origins of industrial development and design, economic factors and societal outcomes, as well as, personal and family memories, all of which general audiences can relate to.
  • 4.1K
  • 30 Mar 2022
Topic Review
Coffee Leaf Miner Leucoptera coffeella
The coffee leaf miner (CLM) Leucoptera coffeella moth is a major threat to coffee production. Insect damage is related to the feeding behavior of the larvae on the leaf. During the immature life stages, the insect feeds in the mesophyll triggering necrosis and causing loss of photosynthetic capacity, defoliation and significant yield loss to coffee crops. Chemical control is used to support the coffee production chain, though market requirements move toward conscious consumption claiming for more sustainable methods.
  • 4.1K
  • 22 Dec 2021
Topic Review
Multiple-Output DC–DC Converters
Multiple-output DC–DC converters are essential in a multitude of applications where different DC output voltages are required. The interest and importance of this type of multiport configuration is also reflected in that many electronics manufacturers currently develop integrated solutions. Traditionally, the different output voltages required are obtained by means of a transformer with several windings, which are in addition to providing electrical isolation. However, the current trend in the development of multiple-output DC–DC converters follows general aspects, such as low losses, high-power density, and high efficiency, as well as the development of new architectures and control strategies.
  • 4.1K
  • 27 Apr 2022
Topic Review
History of South Asian Domes
Islamic rule over northern and central India brought with it the use of domes constructed with stone, brick and mortar, and iron dowels and cramps. Centering was made from timber and bamboo. The use of iron cramps to join together adjacent stones was known in pre-Islamic India, and was used at the base of domes for hoop reinforcement. The synthesis of styles created by this introduction of new forms to the Hindu tradition of trabeate construction created a distinctive architecture. Domes in pre-Mughal India have a standard squat circular shape with a lotus design and bulbous finial at the top, derived from Hindu architecture. Because the Hindu architectural tradition did not include arches, flat corbels were used to transition from the corners of the room to the dome, rather than squinches. In contrast to Persian and Ottoman domes, the domes of Indian tombs tend to be more bulbous.
  • 4.1K
  • 20 Oct 2022
Topic Review
Permanent Magnet Machines for High-Speed Applications
High-speed electrical machines have been extensively researched in the last few decades for industrial and domestic applications, including compressors, vacuum pumps, turbine generators, machine tools, flywheel energy storages, and so on. Compared with low-speed and moderate-speed conventional electrical machines, high-speed electrical machines offer advantages such as high-power density, small size, and light weight. More importantly, high-speed electrical machines can be directly connected to high-speed loads, and conventional gear boxes are no longer needed, which avoids complex gear box systems, improves system efficiency and reliability, and reduces system vibration, noise, and cost. With the evolution in the field of power electronics converters, the problems of high frequency supplies, required for high-speed operation, is no longer a restriction. The development of high-speed electrical machines is also supported by the development of high-speed bearing systems with high robustness, fewer losses, and longer lifetime.
  • 4.1K
  • 17 Jan 2022
Topic Review
Marketing Information System
A marketing information system (MKIS) is a management information system (MIS) designed to support marketing decision making. Jobber (2007) defines it as a "system in which marketing data is formally gathered, stored, analysed and distributed to managers in accordance with their informational needs on a regular basis." In addition, the online business dictionary defines Marketing Information System (MKIS) as "a system that analyzes and assesses marketing information, gathered continuously from sources inside and outside an organization or a store." Furthermore, "an overall Marketing Information System can be defined as a set structure of procedures and methods for the regular, planned collection, analysis and presentation of information for use in making marketing decisions." (Kotler, at al, 2006)
  • 4.1K
  • 17 Oct 2022
Topic Review
Polyphenols against Skin Aging
Polyphenols représente a superfamily of diverse naturally occurring phytochemicals, which exert a particularly potent antioxidant activity, thereby contributing to delay skin aging.
  • 4.1K
  • 19 Nov 2020
Topic Review
Misnagdim
Misnagdim (מתנגדים; also Mitnagdim; singular misnaged/mitnaged) is a Hebrew word meaning "opponents". The term "Misnagdim" commonly refers to opponents of Hasidism. The term "Misnagdim" gained a common usage among Jews living in Europe as the term that referred to Ashkenazi Jews who opposed the rise and spread of early Hasidic Judaism.
  • 4.1K
  • 18 Nov 2022
Topic Review
Ethics in Religion
Ethics involves systematizing, defending, and recommending concepts of right and wrong behavior. A central aspect of ethics is "the good life", the life worth living or life that is simply satisfying, which is held by many philosophers to be more important than traditional moral conduct. Most religions have an ethical component, often derived from purported supernatural revelation or guidance. Some assert that religion is necessary to live ethically. Simon Blackburn states that there are those who "would say that we can only flourish under the umbrella of a strong social order, cemented by common adherence to a particular religious tradition".
  • 4.1K
  • 17 Oct 2022
Topic Review
Torino Scale
The Torino scale is a method for categorizing the impact hazard associated with near-Earth objects (NEOs) such as asteroids and comets. It is intended as a communication tool for astronomers and the public to assess the seriousness of collision predictions, by combining probability statistics and known kinetic damage potentials into a single threat value. The Palermo Technical Impact Hazard Scale is a similar, but more complex scale. Near-Earth objects with a Torino scale of 1 pop up every couple of months or so and may last a few weeks until they have a longer observation arc.
  • 4.1K
  • 21 Nov 2022
Topic Review
Stuttering
Stuttering, also known as stammering, is a speech disorder in which the flow of speech is disrupted by involuntary repetitions and prolongations of sounds, syllables, words, or phrases as well as involuntary silent pauses or blocks in which the person who stutters is unable to produce sounds. The term stuttering is most commonly associated with involuntary sound repetition, but it also encompasses the abnormal hesitation or pausing before speech, referred to by people who stutter as blocks, and the prolongation of certain sounds, usually vowels or semivowels. According to Watkins et al., stuttering is a disorder of "selection, initiation, and execution of motor sequences necessary for fluent speech production". For many people who stutter, repetition is the main concern. The term "stuttering" covers a wide range of severity, from barely perceptible impediments that are largely cosmetic to severe symptoms that effectively prevent oral communication. Almost 70 million people worldwide stutter, about 1% of the world's population. The impact of stuttering on a person's functioning and emotional state can be severe. This may include fears of having to enunciate specific vowels or consonants, fears of being caught stuttering in social situations, self-imposed isolation, anxiety, stress, shame, low self-esteem, being a possible target of bullying (especially in children), having to use word substitution and rearrange words in a sentence to hide stuttering, or a feeling of "loss of control" during speech. Stuttering is sometimes popularly seen as a symptom of anxiety, but there is no direct correlation in that direction. Stuttering is generally not a problem with the physical production of speech sounds or putting thoughts into words. Acute nervousness and stress are not thought to cause stuttering, but they can trigger stuttering in people who have the speech disorder, and living with a stigmatized disability can result in anxiety and high allostatic stress load (chronic nervousness and stress) that reduce the amount of acute stress necessary to trigger stuttering in any given person who stutters, worsening the situation in the manner of a positive feedback system; the name 'stuttered speech syndrome' has been proposed for this condition. Neither acute nor chronic stress, however, itself creates any predisposition to stuttering. The disorder is also variable, which means that in certain situations, such as talking on the telephone or in a large group, the stuttering might be more severe or less, depending on whether or not the person who stutters is self-conscious about their stuttering. People who stutter often find that their stuttering fluctuates and that they have "good" days, "bad" days and "stutter-free" days. The times in which their stuttering fluctuates can be random. Although the exact etiology, or cause, of stuttering is unknown, both genetics and neurophysiology are thought to contribute. There are many treatments and speech therapy techniques available that may help decrease speech disfluency in some people who stutter to the point where an untrained ear cannot identify a problem; however, there is essentially no cure for the disorder at present. The severity of the person's stuttering would correspond to the amount of speech therapy needed to decrease disfluency. For severe stuttering, long-term therapy and hard work is required to decrease disfluency.
  • 4.1K
  • 23 Nov 2022
Topic Review
Silicon-Based Optical Phased Array Lidar
Silicon-based Lidar is an ideal way to reduce the volume of the Lidar and realize monolithic integration. It removes the moving parts in the conventional device and realizes solid-state beam steering. The advantages of low cost, small size, and high beam steering speed have attracted the attention of many researchers. 
  • 4.1K
  • 07 Jul 2023
Topic Review
Self-Amplifying mRNA Vaccine
The core principle behind mRNA vaccines is to encode the antigen in the mRNA and then to deliver the transcript to the host cell cytoplasm using a non-viral delivery system, allowing antigen expression and induction of an antigen-specific immune response. Self-amplifying RNA (saRNA) is a type of mRNA that also encodes viral replicase, which enables the RNA to self-replicate upon delivery into the cell.
  • 4.1K
  • 13 Feb 2021
Topic Review
History of Intersex Surgery
The history of intersex surgery is intertwined with the development of the specialities of pediatric surgery, pediatric urology, and pediatric endocrinology, with our increasingly refined understanding of sexual differentiation, with the development of political advocacy groups united by a human qualified analysis, and in the last decade by doubts as to efficacy, and controversy over when and even whether some procedures should be performed. Prior to the medicalization of intersex, Canon and common law referred to a person's sex as male, female or hermaphrodite, with legal rights as male or female depending on the characteristics that appeared most dominant. The foundation of common law, the Institutes of the Lawes of England described how a hermaphrodite could inherit "either as male or female, according to that kind of sexe which doth prevaile." Single cases have been described by legal cases sporadically over the centuries. Modern ideas of medicalization of intersex and birth defects can be traced to French anatomist Isidore Geoffroy Saint-Hilaire (1805–1861), who pioneered the field of teratology. Since the 1920s surgeons have attempted to "fix" an increasing variety of conditions. Success has often been partial and surgery is often associated with minor or major, transient or permanent complications. Techniques in all fields of surgery are frequently revised in a quest for higher success rates and lower complication rates. Some surgeons, well aware of the immediate limitations and risks of surgery, feel that significant rates of imperfect outcomes are no scandal (especially for the more severe and disabling conditions). Instead they see these negative outcomes as a challenge to be overcome by improving the techniques. Genital reconstruction evolved within this tradition. In recent decades, nearly every aspect of this perspective has been called into question, with increasing concern regarding the human rights implications of medical interventions.
  • 4.1K
  • 01 Nov 2022
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