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Topic Review
List of AEW&C Aircraft Operators
Airborne early warning and control (AEW&C) aircraft are airborne radar systems designed to detect and track aircraft, missiles, ships and vehicles and provide command and control to direct friendly forces. Some operators, such as the Royal Air Force refer to such aircraft as Airborne early warning (AEW), while others reserve the shorter name for AEW aircraft lacking command and control facilities.
  • 4.6K
  • 03 Nov 2022
Topic Review
Tendencies Affecting Growth and Cultivation of Genus Spirulina
Spirulina, a kind of blue-green algae, is one of the Earth’s oldest known forms of life. Spirulina grows best in very alkaline environments, although it may flourish across a wide variety of pH values. There are several techniques for growing Spirulina spp., ranging from open systems such as ponds and lakes, which are vulnerable to contamination by animals and extraterrestrial species, to closed systems such as photovoltaic reactors, which are not. Most contaminated toxins come from other toxic algae species that become mixed up during harvest, necessitating the study of spirulina production processes at home. Lighting, temperature, inoculation volume, stirring speed, dissolved particles, pH, water quality, and overall micronutrient richness are only a few of the environmental parameters influencing spirulina production.
  • 4.6K
  • 08 Dec 2022
Topic Review
Giardia lamblia
Giardia lamblia, also known as Giardia intestinalis, is a flagellated parasitic microorganism, that colonizes and reproduces in the small intestine, causing giardiasis. The parasite attaches to the epithelium by a ventral adhesive disc or sucker, and reproduces via binary fission. Giardiasis does not spread via the bloodstream, nor does it spread to other parts of the gastrointestinal tract, but remains confined to the lumen of the small intestine. Giardia trophozoites absorb their nutrients from the lumen of the small intestine, and are anaerobes. If the organism is split and stained, its characteristic pattern resembles the familiar "smiley face" symbol. Chief pathways of human infection include ingestion of untreated sewage, a phenomenon particularly common in many developing countries; contamination of natural waters also occurs in watersheds where intensive grazing occurs. Giardia infections occur worldwide, however Giardia lamblia is the most commonly identified intestinal parasite in the United States and Canada among children in day care centers, hikers, family members, homosexual male partners and immunocompromised adults. Approximately 20,000 cases per year in the United States are reported.
  • 4.6K
  • 25 Oct 2022
Topic Review
Imamah (Shia)
Template:Infobox monarchyTemplate:Aqidah In Shia Islam, the imamah (Arabic: إمامة) is the doctrine that the figures known as imams are rightfully the central figures of the ummah; the entire Shi'ite system of doctrine focuses on the imamah. Shi'ites believe that the Imams are the true Caliphs or rightful successors of Muhammad, and further that Imams are possessed of divine knowledge and authority (Ismah) as well as being part of the Ahl al-Bayt, the family of Muhammad. These Imams have the role of providing commentary and interpretation of the Quran as well as guidance. According to Nasir al-Din al-Tusi, the Imam is a means through which humans receive divine grace, because "He brings men closer to obedience (of Allah) and keeps them away from disobedience." As fulfilling the human being is his wish, it is logical that God appoints Imams to subject man to his wishes. So his existence and his deeds display two forms of grace of God toward man.
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  • 01 Nov 2022
Topic Review
Yield (Engineering)
In materials science and engineering, the yield point is the point on a stress-strain curve that indicates the limit of elastic behavior and the beginning of plastic behavior. Below the yield point, a material will deform elastically and will return to its original shape when the applied stress is removed. Once the yield point is passed, some fraction of the deformation will be permanent and non-reversible and is known as plastic deformation. The yield strength or yield stress is a material property and is the stress corresponding to the yield point at which the material begins to deform plastically. The yield strength is often used to determine the maximum allowable load in a mechanical component, since it represents the upper limit to forces that can be applied without producing permanent deformation. In some materials, such as aluminium, there is a gradual onset of non-linear behavior, making the precise yield point difficult to determine. In such a case, the offset yield point (or proof stress) is taken as the stress at which 0.2% plastic deformation occurs. Yielding is a gradual failure mode which is normally not catastrophic, unlike ultimate failure. In solid mechanics, the yield point can be specified in terms of the three-dimensional principal stresses ([math]\displaystyle{ \sigma_1, \sigma_2 , \sigma_3 }[/math]) with a yield surface or a yield criterion. A variety of yield criteria have been developed for different materials.
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  • 17 Oct 2022
Topic Review
Bamboo Node’s Vascular Bundle
The vascular bundle is an important structural unit that determines the growth and properties of bamboo. A high-resolution X-ray microtomography (μCT) was used to observe and reconstruct a three-dimensional (3D) morphometry model of the vascular bundle of the Qiongzhuea tumidinoda node due to its advantages of quick, nondestructive, and accurate testing of plant internal structure.
  • 4.6K
  • 23 Dec 2021
Topic Review
Mo Siang Online
Mo Siang Online is an MMORPG based on the warring states of ancient China . The game is mainly focused on Martial Arts and Kung Fu, allowing each character to choose 6 fighting styles. At present, Mo Siang only has five English servers and eight Chinese servers with their own language interface.The Korean game developer once released its global server and renamed this game as Titan, but this game used to be called as Dark Story in Korea with its Korean server. In Japan, Mo Siang is called Feats of Arms. After the agent in Japan is replaced, this game is renamed as Crest of Jade. The Japanese game distributor run its Beta on 19th Feb. 2009. From August 2009 on, there is another English version of Mo Siang released, the game agent PlayOMG renames this game as Azuga, Age of Chaos. On the contrary, from September 2009 on, the Japanese game agent of Mo Siang decides to close their server.
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  • 22 Nov 2022
Topic Review
Silvicultural Site Preparation Techniques
Silvicultural site preparation techniques are planned anthropogenic disturbances that are designed to aid in the regeneration and establishment of a new stand of trees.
  • 4.6K
  • 09 Dec 2020
Topic Review
Honey in Treatment of COVID-19 Infection
The emergence of COVID-19, caused by the SARS-CoV-2 virus, led to the pursuit of solutions for the treatment of symptoms and/or disease. Honey has proven to be effective against viral infections, principally due to its potential antioxidant and anti-inflammatory activities that attenuate oxidative damage induced by pathogens, and by improving the immune system.
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  • 22 Aug 2022
Topic Review
Parabolic Aluminized Reflector Light
A parabolic aluminized reflector lamp (also PARCAN light, PARcan, or simply PAR) is a type of electric lamp that is widely used in commercial, residential, and transportation illumination. Usage includes locomotive headlamps, aircraft landing lights, and residential and commercial recessed lights ("cans" in the United States). They are identical in principle to sealed beam automobile headlights. The lamps and their fixtures are widely used in theatre, concerts and motion picture production when a substantial amount of flat lighting is required for a scene. In situations where sunlight or other specular light is available, a white foam reflector is often used to accomplish the same effect as a PAR array. PAR cans are being replaced in some stage applications by LED PAR cans, which use less electric power and produce a wide array of saturated colors without the use of color filters, when white light is not needed.
  • 4.6K
  • 18 Oct 2022
Topic Review
Surfactants versus Biosurfactants
Based on their origin and composition, surfactants can be divided into three different categories: (i) synthetic surfactants; (ii) bio-based surfactants; and (iii) microbial biosurfactants. The first group is the most widespread and cost-effective. It is composed of surfactants, which are synthetically produced, using non-renewable sources, with a final structure that is different from the natural components of living cells. The second category comprises surfactants of intermediate biocompatibility, usually produced by chemical synthesis but integrating fats, sugars or amino acids obtained from renewable sources into their structure. Finally, the third group of surfactants, designated as microbial biosurfactants, are considered the most biocompatible and eco-friendly, as they are produced by living cells, mostly bacteria and yeasts, without the intermediation of organic synthesis.
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  • 14 Mar 2021
Topic Review
Green Tea
Green tea is a type of tea that is made from Camellia sinensis leaves that have not undergone the same withering and oxidation process used to make oolong teas and black teas. Green tea originated in China , but its production and manufacture has spread to many other countries in Asia. Several varieties of green tea exist, which differ substantially based on the variety of C. sinensis used, growing conditions, horticultural methods, production processing, and time of harvest. Although there has been considerable research on the possible health effects of consuming green tea regularly, there is little evidence that drinking green tea has any effects on health.
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  • 08 Nov 2022
Topic Review
Education of Midwives in Portugal and Spain
In Europe, midwives education, in accordance with the principles of the Bologna Declaration, are based on the pillars defined by Directive 2005/36/CE and by the Munich Declaration. In Portugal, the candidate applies on their own initiative to one of the Higher Education Institutions (HEIs) that provide such training. At the end of the education, students will achieve the master title. In Spain, the candidate sits for a state exam, which is announced annually by each autonomous community, for admission to the specialization.
  • 4.6K
  • 24 Jun 2022
Topic Review
Surface Treatment in PDMS-Microfluidic Devices
Microfluidic lab-on-a-chip cell culture techniques have been gaining popularity by offering the possibility of reducing the amount of samples and reagents with greater control over the cellular microenvironment. Polydimethylsiloxane (PDMS) is the commonly used polymer for microfluidic cell culture devices because of the cheap and easy fabrication techniques, non-toxicity, biocompatibility, high gas permeability, and optical transparency.
  • 4.6K
  • 07 Dec 2021
Topic Review
Theory of Planned Behavior and Perceived Consumer Effectiveness
The Theory of Planned Behavior (TPB) is a further development of the Theory of Reasoned Action (TRA) to predict an individual’s intention to engage in a specific behavior. The theory aims to explain the behavioral intention over which an individual has the ability to exert self-control. It claims that the individual’s intention to perform a specific behavior is mainly influenced by three key elements—attitude, subjective norm, and perceived behavioral control—and an individual with strong intention is more likely to perform an actual behavior.
  • 4.6K
  • 19 Jan 2024
Topic Review
Impact of Wildfires on Ecosystems and Wildlife
Wildfires are common occurrences worldwide that can destroy vast forest areas and kill numerous animals in a few hours. The researchers describe how the different species are expected to behave during a wildfire and the impacts on the ecosystem. 
  • 4.6K
  • 10 Feb 2023
Topic Review
Sustainable Housing in Rwanda
Baked clay bricks (Impunyu) is the dominant wall construction material in Rwanda. Clay deposits in the country’s lowlands are utilized for baked clay bricks. Despite the ongoing campaign, the use of wood by some local brick producers is unfriendly to the environment. Recent research has called for alternative methods in order to reduce the cost and impact on the environment. Earlier efforts with compressed earth blocks were saddled with weight and a substantial use of cement for good surface texture and adequate resistance against surface erosion. This research explored the potentials of using an appropriate dose of clay (from Muhanzi), volcanic light aggregate (Amakoro, (from Musanze)), and cement to produce unbaked shelled compressed earth blocks (SCEB). SCEB is a compressed earth block with an outer shell and inner core of different cement content or materials, compressed into a unit block. The result is a masonry unit with a higher surface resistance, durability, and desirable architectural effect produced with a 60% reduction in cement content. A weight reduction of 12% was achieved with an optimum content of 33% of the volcanic lightweight aggregate. A cost reduction of 25% was recorded over conventional compressed earth brick walls and a 54% over sand-cement block walls. Possible future trends were also identified with appreciable prospects in earthen architecture. 
  • 4.6K
  • 29 Jul 2021
Topic Review
MMR Vaccine Controversy
A controversy surrounding the combined measles, mumps, and rubella (MMR) vaccine started with the 1998 publication of a fraudulent research paper in The Lancet linking the vaccine to colitis and autism spectrum disorders. The claims in the paper were widely reported, leading to a sharp drop in vaccination rates in the UK and Ireland and increases in the incidence of measles and mumps, resulting in deaths and serious permanent injuries. Following the initial claims in 1998, multiple large epidemiological studies were undertaken. Reviews of the evidence by the Centers for Disease Control and Prevention, the American Academy of Pediatrics, the Institute of Medicine of the US National Academy of Sciences, the UK National Health Service, and the Cochrane Library all found no link between the MMR vaccine and autism. An investigation by journalist Brian Deer found that Andrew Wakefield, the author of the original research paper linking the vaccine to autism, had multiple undeclared conflicts of interest, had manipulated evidence, and had broken other ethical codes. The Lancet paper was partially retracted in 2004 and fully retracted in 2010, when Lancet's editor-in-chief Richard Horton described it as "utterly false" and said that the journal had been deceived. Wakefield was found guilty by the General Medical Council of serious professional misconduct in May 2010 and was struck off the Medical Register, meaning he could no longer practise as a doctor in the UK. In 2011, Deer provided further information on Wakefield's improper research practices to the British Medical Journal, which in a signed editorial described the original paper as fraudulent. The scientific consensus is that there is no link between the MMR vaccine and autism and that the vaccine's benefits greatly outweigh its risks. Wakefield's paper was described as "perhaps, the most damaging medical hoax of the last 100 years". Physicians, medical journals, and editors have described Wakefield's actions as fraudulent and tied them to epidemics and deaths.
  • 4.6K
  • 21 Oct 2022
Topic Review
DESCRIPTION OF THE MITOCHONDRIAL PORIN VDAC1 AND ITS DISEASE RELEVANCE
Mitochondrial porins or voltage-dependent anionic channels (VDAC) are nonspecific channels that determine the permeability of the mitochondrial outer membrane (MEM). Its molecular mass oscillates around 28 to 36 kDa. These channels represent the most abundant proteins of the MEM. They are freely permeable to hydrophilic solutes and the limit of exclusion of metabolites is 3 to 6 kDa. These channels are the main route for the diffusion of ions such as pyruvate and ATP, among others. It has been proposed that the transport of these metabolites regulates the cellular energy supply. This review focus on some of the main aspects of the VDAC porins and its relevance in some physiological processes related with cancer and neurodegeneration diseases. 
  • 4.6K
  • 30 Oct 2020
Topic Review
Language Attrition
Language attrition is the loss of a first or second language or a portion of that language by either a community or an individual. Language attrition is related to multilingualism and language acquisition. Many factors are at play in learning (acquisition) and unlearning (loss) the first and second languages. This can be a simple reversal of learning. In other cases, the type and speed of attrition depends on the individual, also on his or her age and skill level. For the same second language, attrition has been affected differently depending on what is the dominant first language environment. In many cases, attrition could well be case-by-case. Those language learners motivated to keep their first and second languages may very well maintain it, although to do so will likely involve continuous study, or regular use of both.
  • 4.6K
  • 01 Dec 2022
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