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Topic Review
Peroxisomal β-Oxidation
It is not paradoxical that what has been overlooked tends to be of great importance. Peroxisomes, the widely distributed organelles in the body, play irreplaceable roles in cellular metabolism, especially in fatty acid oxidation (FAO) and the generation and elimination of reactive oxygen species (ROS).
  • 8.5K
  • 15 Jul 2022
Topic Review
List of Folk Heroes
This is a list of folk heroes.
  • 8.5K
  • 17 Oct 2022
Topic Review
International Trade Theory
International trade theory is a sub-field of economics which analyzes the patterns of international trade, its origins, and its welfare implications. International trade policy has been highly controversial since the 18th century. International trade theory and economics itself have developed as means to evaluate the effects of trade policies.
  • 8.5K
  • 14 Nov 2022
Topic Review
Responsive Architecture
Responsive architecture is a type of architecture, an artificial entity, that reacts to data and information collected by a variety of types of sensors. It is also defined as an interactive and collective platform where diverse computing or operating systems are executed, leading to architectural behaviors like changing forms or services.
  • 8.5K
  • 20 May 2021
Topic Review
Turbocharged Direct Injection
Turbocharged direct injection or TDI is a design of turbodiesel engines featuring turbocharging and cylinder-direct fuel injection that was developed and produced by the Volkswagen Group (VW AG). These TDI engines are widely used in all mainstream Volkswagen Group marques of passenger cars and light commercial vehicles made by the company (particularly those sold in Europe). They are also used as marine engines in Volkswagen Marine and Volkswagen Industrial Motor applications. TDI engines installed in 2009 to 2015 model year Volkswagen Group cars sold through 18 September 2015 had an emissions defeat device, which activated emissions controls only during emissions testing. The emissions controls were suppressed otherwise, allowing the TDI engines to exceed legal limits on emissions. VW has admitted to using the illegal device in its TDI diesel cars. In many countries, TDI is a registered trademark of Volkswagen AG. The TDI designation has also been used on vehicles powered by Land Rover-designed diesel engines. These are unrelated to Volkswagen Group engines.
  • 8.5K
  • 08 Nov 2022
Topic Review
Incineration Bottom Ash from Municipal Solid Waste
Incineration bottom ash (IBA) is the main residue from municipal solid waste (MSW) incineration and refers to the incombustible materials that remain in the furnace after combustion. IBA is a very heterogeneous material, comprising irregularly shaped particles and a wide particle size distribution. This material is a complex inorganic mixture generally composed of melt products, minerals, metallic compounds, ceramics, and glass [1]. The classification and the management practices of IBA differ worldwide and, particularly, among the EU Member States. However, different applications have been studied for this material.
  • 8.5K
  • 24 Dec 2021
Topic Review
Leucaena leucocephala as Protein Source
White leadtree or Leucaena (Leucaena leucocephala) (), also known as ipil-ipil, is native to Central America and has spread and/or naturalized all over the World at a latitude between 30° N and 30° S due to a shrub variety used as a shade tree for coffee, cocoa, hemp plantations, pepper, vanilla, and other essences.
  • 8.4K
  • 04 Aug 2021
Topic Review
Lewis's Trilemma
Lewis's trilemma is an apologetic argument traditionally used to argue for the divinity of Jesus by arguing that the only alternatives were that he was evil or deluded. One version was popularised by University of Oxford literary scholar and writer C. S. Lewis in a BBC radio talk and in his writings. It is sometimes described as the "Lunatic, Liar, or Lord", or "Mad, Bad, or God" argument. It takes the form of a trilemma — a choice among three options, each of which is in some way difficult to accept. This argument is very popular with Christian apologists, although some theologians and biblical scholars do not view Jesus as having claimed to be God. Some argue that he identified himself as a divine agent, with a unique relationship to Israel's God. Others see him as wanting to direct attention to the divine kingdom he proclaimed.
  • 8.4K
  • 10 Nov 2022
Topic Review
Cluster Chemistry
In chemistry, a cluster is an ensemble of bound atoms or molecules that is intermediate in size between a molecule and a bulk solid. Clusters exist of diverse stoichiometries and nuclearities. For example, carbon and boron atoms form fullerene and borane clusters, respectively. Transition metals and main group elements form especially robust clusters. Clusters can also consist solely of a certain kind of molecules, such as water clusters. The phrase cluster was coined by F.A. Cotton in the early 1960s to refer to compounds containing metal–metal bonds. In another definition a cluster compound contains a group of two or more metal atoms where direct and substantial metal bonding is present. The prefixed terms "nuclear" and "metallic" are used and imply different meanings. For example, polynuclear refers to a cluster with more than one metal atom, regardless of the elemental identities. Heteronuclear refers to a cluster with at least two different metal elements. The main cluster types are "naked" clusters (without stabilizing ligands) and those with ligands. For transition metal clusters, typical stabilizing ligands include carbon monoxide, halides, isocyanides, alkenes, and hydrides. For main group elements, typical clusters are stabilized by hydride ligands. Transition metal clusters are frequently composed of refractory metal atoms. In general metal centers with extended d-orbitals form stable clusters because of favorable overlap of valence orbitals. Thus, metals with a low oxidation state for the later metals and mid-oxidation states for the early metals tend to form stable clusters. Polynuclear metal carbonyls are generally found in late transition metals with low formal oxidation states. The polyhedral skeletal electron pair theory or Wade's electron counting rules predict trends in the stability and structures of many metal clusters. Jemmis mno rules have provided additional insight into the relative stability of metal clusters.
  • 8.4K
  • 08 Nov 2022
Topic Review
Cat Café
A cat café is a theme café whose attraction is cats who can be watched and played with. Patrons pay a cover fee, generally hourly, and thus cat cafés can be seen as a form of supervised indoor pet rental. "Cat café" has been officially recognized in the online edition of the Oxford Dictionary of English since August 2015.
  • 8.4K
  • 20 Oct 2022
Topic Review
The Sims 2 Stuff Packs
Stuff packs are minor expansion packs for The Sims 2 that add new items, clothing, and furniture to the game without implementing any significant changes to gameplay.
  • 8.4K
  • 17 Nov 2022
Topic Review
Water-Gas Shift Reaction
The water-gas shift reaction (WGSR) describes the reaction of carbon monoxide and water vapor to form carbon dioxide and hydrogen: The water gas shift reaction was discovered by Italian physicist Felice Fontana in 1780. It was not until much later that the industrial value of this reaction was realized. Before the early 20th century, hydrogen was obtained by reacting steam under high pressure with iron to produce iron, iron oxide and hydrogen. With the development of industrial processes that required hydrogen, such as the Haber–Bosch ammonia synthesis, a less expensive and more efficient method of hydrogen production was needed. As a resolution to this problem, the WGSR was combined with the gasification of coal to produce a pure hydrogen product. As the idea of hydrogen economy gains popularity, the focus on hydrogen as a replacement fuel source for hydrocarbons is increasing.
  • 8.4K
  • 22 Nov 2022
Topic Review
History of Democratic Socialism
Democratic socialism represents the modernist development of socialism and its outspoken support for democracy. The origins of democratic socialism can be traced back to 19th-century utopian socialist thinkers and the Chartist movement in Great Britain, which somewhat differed in their goals but shared a common demand of democratic decision making and public ownership of the means of production, and viewed these as fundamental characteristics of the society they advocated for. Democratic socialism was also heavily influenced by the gradualist form of socialism promoted by the British Fabian Society and Eduard Bernstein's evolutionary socialism. In the 19th century, the ruling classes were afraid of socialism because it challenged their rule. Socialism has faced opposition since then, and the opposition to it has often been organized and violent. In countries such as Germany and Italy, democratic socialist parties were banned, like with Otto von Bismarck's Anti-Socialist Laws. With the expansion of liberal democracy and universal suffrage during the 20th century, democratic socialism became a mainstream movement which expanded across the world, as centre-left and left-wing parties came to govern, became the main opposition party, or simply a commonality of the democratic process in most of the Western world; one major exception was the United States. Democratic socialist parties greatly contributed to existing liberal democracy.
  • 8.4K
  • 22 Nov 2022
Topic Review
Literacy
Literacy is traditionally defined as the ability to read and write. In the modern world, this is one way of interpreting literacy. A more broad interpretation is literacy as knowledge and competence in a specific area. The concept of literacy has evolved in meaning. The modern term's meaning has been expanded to include the ability to use language, numbers, images, computers, and other basic means to understand, communicate, gain useful knowledge, solve mathematical problems and use the dominant symbol systems of a culture. The concept of literacy is expanding across OECD countries to include skills to access knowledge through technology and ability to assess complex contexts. A person who travels and resides in a foreign country but is unable to read or write in the language of the host country would also be regarded by the locals as illiterate. The key to literacy is reading development, a progression of skills that begins with the ability to understand spoken words and decode written words, and culminates in the deep understanding of text. Reading development involves a range of complex language underpinnings including awareness of speech sounds (phonology), spelling patterns (orthography), word meaning (semantics), grammar (syntax) and patterns of word formation (morphology), all of which provide a necessary platform for reading fluency and comprehension. Once these skills are acquired, the reader can attain full language literacy, which includes the abilities to apply to printed material critical analysis, inference and synthesis; to write with accuracy and coherence; and to use information and insights from text as the basis for informed decisions and creative thought. The inability to do so is called illiteracy or analphabetism. The United Nations Educational, Scientific and Cultural Organization (UNESCO) defines literacy as the "ability to identify, understand, interpret, create, communicate and compute, using printed and written materials associated with varying contexts. Literacy involves a continuum of learning in enabling individuals to achieve their goals, to develop their knowledge and potential, and to participate fully in their community and wider society".
  • 8.4K
  • 05 Dec 2022
Topic Review
Bayraktar Tactical UAS
The Bayraktar Tactical UAS is a surveillance and reconnaissance unmanned aerial vehicle (UAV) initially developed for the Turkish Armed Forces. It is developed by the Kale-Baykar, a joint venture between the Kale Group and Baykar Technologies. In 2014, Bayraktar held the national endurance and altitude record for Turkey's unmanned aerial vehicles (UAV). It set a record for autonomous flight endurance when it flew 24 hours and 34 minutes at 18,000 feet on 5 August 2014. It furthermore recorded highest altitude of 27,030 feet on its flight on 14 June 2014 with full payload. Bayraktar TB2 successfully demonstrated firing of ROKETSAN MAM-L Smart Micro Munition with 100% accuracy in December 2015. While the Turkish Armed Forces describes Bayraktar as "Tactical UAV Class" to prevent it from being a competitor to the TAI Anka UAV, international standards would classify it as a medium-altitude long-endurance UAV. With its 650 kg MTOW and 12 meters wingspan platform powered by an internal combustion engine, Bayraktar is capable of flying at 22,500 feet and loitering for more than 24 hours.
  • 8.4K
  • 24 Oct 2022
Topic Review
Perovskite Materials
In the development of hydrogen-based technology, a key challenge is the sustainable production of hydrogen in terms of energy consumption and environmental aspects. However, existing methods mainly rely on fossil fuels due to their cost efficiency, and as such, it is difficult to be completely independent of carbon-based technology. Electrochemical hydrogen production is essential, since it has shown the successful generation of hydrogen gas of high purity. Similarly, the photoelectrochemical (PEC) method is also appealing, as this method exhibits highly active and stable water splitting with the help of solar energy. We discuss the exceptional optical and electrical characteristics of perovskite materials which often dictate PEC performance. We further extend our discussion to the material limit of perovskite under a hydrogen production environment, i.e., that PEC reactions often degrade the contact between the electrode and the electrolyte.
  • 8.4K
  • 30 Jul 2021
Topic Review
Slope Stability Analysis
Slope stability analysis is performed to assess the safe design of a human-made or natural slopes (e.g. embankments, road cuts, open-pit mining, excavations, landfills etc.) and the equilibrium conditions. Slope stability is the resistance of inclined surface to failure by sliding or collapsing. The main objectives of slope stability analysis are finding endangered areas, investigation of potential failure mechanisms, determination of the slope sensitivity to different triggering mechanisms, designing of optimal slopes with regard to safety, reliability and economics, designing possible remedial measures, e.g. barriers and stabilization. Successful design of the slope requires geological information and site characteristics, e.g. properties of soil/rock mass, slope geometry, groundwater conditions, alternation of materials by faulting, joint or discontinuity systems, movements and tension in joints, earthquake activity etc. The presence of water has a detrimental effect on slope stability. Water pressure acting in the pore spaces, fractures or other discontinuities in the materials that make up the pit slope will reduce the strength of those materials. Choice of correct analysis technique depends on both site conditions and the potential mode of failure, with careful consideration being given to the varying strengths, weaknesses and limitations inherent in each methodology. Before the computer age stability analysis was performed graphically or by using a hand-held calculator. Today engineers have a lot of possibilities to use analysis software, ranges from simple limit equilibrium techniques through to computational limit analysis approaches (e.g. Finite element limit analysis, Discontinuity layout optimization) to complex and sophisticated numerical solutions (finite-/distinct-element codes). The engineer must fully understand limitations of each technique. For example, limit equilibrium is most commonly used and simple solution method, but it can become inadequate if the slope fails by complex mechanisms (e.g. internal deformation and brittle fracture, progressive creep, liquefaction of weaker soil layers, etc.). In these cases more sophisticated numerical modelling techniques should be utilised. Also, even for very simple slopes, the results obtained with typical limit equilibrium methods currently in use (Bishop, Spencer, etc.) may differ considerably. In addition, the use of the risk assessment concept is increasing today. Risk assessment is concerned with both the consequence of slope failure and the probability of failure (both require an understanding of the failure mechanism). Within the last decade (2003) Slope Stability Radar has been developed to remotely scan a rock slope to monitor the spatial deformation of the face. Small movements of a rough wall can be detected with sub-millimeter accuracy by using interferometry techniques.
  • 8.4K
  • 19 Oct 2022
Topic Review
Consanguinity
Consanguinity ("blood relation", from Latin consanguinitas) is the property of being from the same kinship as another person. In that aspect, consanguinity is the quality of being descended from the same ancestor as another person. The laws of many jurisdictions set out the degree of consanguinity in relation to prohibited sexual relations and marriage parties. Such rules are also used to determine heirs of an estate according to statutes that govern intestate succession, which vary from jurisdiction to jurisdiction. In some places and times, cousin marriage is approved and expected; in others, it is taboo as incest. The degree of relative consanguinity can be illustrated with a consanguinity table in which each level of lineal consanguinity (generation or meiosis) appears as a row, and individuals with a collaterally consanguineous relationship share the same row. The Knot System is a numerical notation that defines consanguinity.
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  • 28 Sep 2022
Topic Review
Mercedes-Benz W108
The Mercedes-Benz W108 and W109 are luxury cars produced by Mercedes-Benz from 1965 through to 1972 and 1973 in North America only. The line was an update of the predecessor W111 and W112 fintail sedans. The cars were successful in West Germany and in export markets including North America and Southeast Asia. During the seven-year run, a total of 383,361 units were manufactured.
  • 8.4K
  • 19 Oct 2022
Topic Review
Parental Involvement
Parental involvement is seen as an important strategy for the advancement of the quality of education. The ultimate objective of this is to expand the academic and social capacities of students, especially those of disadvantaged backgrounds determined by ethnic minority origin and low socio-economic status. In this contribution, various forms of both parental and school-initiated involvement will be described. In addition, results of studies into the effectiveness of parental involvement will be presented.
  • 8.4K
  • 15 Nov 2021
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