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Topic Review
Ascorbic Acid-Mediated Reactions
Ascorbic acid is a vitamin found in different types of food. It has tremendous medical applications in several different fields such as in pharmaceuticals, cosmetics, and in organic synthesis. 
  • 5.5K
  • 25 Nov 2020
Topic Review
Human Mobility and Smart City
Human mobility, the movement of human beings in space and time, reflects the spatial-temporal characteristics of human behavior. With big data analytics, human mobility research can be used to facilitate smart city development, in multiple disciplines such as smart traffic, smart urban planning, smart health, smart safety, smart commerce, etc. A framework for linking international academic research and city-level management policy was established and applied to the case of Hong Kong. Literatures regarding human mobility research using big data are reviewed. These studies contribute to (1) discovering the spatial-temporal phenomenon, (2) identifying the difference in human behaviour or spatial attributes, (3) explaining the dynamic of mobility, and (4) applying to city management. Then, the application of the research to smart city development are scrutinised based on email queries to various governmental departments in Hong Kong. With further improvement in the practical value of data analytics and the utilization of data sourced from multiple sectors, paths to achieve smarter cities from policymaking perspectives are highlighted.
  • 5.5K
  • 06 Jun 2021
Topic Review
Religious Views on Euthanasia
There are many religious views on euthanasia, although many moral theologians are critical of the procedure.
  • 5.5K
  • 15 Nov 2022
Topic Review
Role-Playing Games
Role-Playing Games may be defined as a system for creating stories based on rules. They allow a group of players and a game director (also known as Game Master or Narrator) to participate and interact using their imagination to determine what could happen. There are different kinds of Role-Playing Games (RPGs) that relate to video games and online video games. The original RPGs, sometimes called tabletop RPGs or pen-and-paper RPGs, were the starting point of their digital relatives, and used mainly speech and imagination; however, technology may be used in some cases for communication. RPGs that are played by writing posts in forums or sending emails are called Play by Post (PbP). Some RPGs even require live interaction, similar to theater representations; these are called Live Action Role Play (LARP).
  • 5.4K
  • 16 Dec 2021
Biography
E. Michael Jones
Eugene Michael Jones (born May 4, 1948) is an American writer, former professor, media commentator and the current editor of Culture Wars magazine (formerly Fidelity Magazine). Jones is known for his writings from a perspective which defends the Catholic Church in American society and overviews the decline of the Catholic communities which were assimilated into the secular American mainstream af
  • 5.4K
  • 29 Dec 2022
Topic Review
Home Economics
Home economics, or family and consumer sciences, is a subject concerning human development, personal and family finances, consumer issues, housing and interior design, nutrition and food preparation, as well as textiles and apparel. Home economics courses are offered around the world and across multiple educational levels. Internationally, it is coordinated by the International Federation for Home Economics. Historically, the purpose of these courses was to professionalize housework, to provide intellectual fulfillment for women, and to emphasize the value of "women's work" in society and to prepare them for the traditional roles of sexes. However, it has since evolved into family and consumer sciences to cover additional subject matter outside of just home life and wellness. Family and consumer sciences are taught as an elective or required course in secondary education, as a continuing education course in institutions, and at the primary level.   Beginning as home economics in the United States, the course was a key part of the education system for teaching one the art of taking care of a household. In the 19th and early 20th century, it was a woman-dominated course, teaching women to be homemakers and efficient household managers. The American Association of Family and Consumer Sciences was created as an answer to more Americans desiring youth to learn vocational skills. Politics played a role in home economics education, and it wasn’t until later in the century that the course shifted from being woman-dominated to now required for both sexes.   Now family and consumer science have been included in the broader subject of Career Technical Education, a program that teaches skilled trades, applied sciences, modern technologies, and career preparation. Despite the subjects over the past century, there has been a major decline in home economics courses offered by educational institutions.  
  • 5.4K
  • 09 Nov 2022
Topic Review
Bell Test Experiments
A Bell test experiment or Bell's inequality experiment, also simply a Bell test, is a real-world physics experiment designed to test the theory of quantum mechanics in relation to Albert Einstein's concept of local realism. The experiments test whether or not the real world satisfies local realism, which requires the presence of some additional local variables (called "hidden" because they are not a feature of quantum theory) to explain the behavior of particles like photons and electrons. To date, all Bell tests have found that the hypothesis of local hidden variables is inconsistent with the way that physical systems behave. According to Bell's theorem, if nature actually operates in accord with any theory of local hidden variables, then the results of a Bell test will be constrained in a particular, quantifiable way. If a Bell test is performed in a laboratory and the results are not thus constrained, then they are inconsistent with the hypothesis that local hidden variables exist. Such results would support the position that there is no way to explain the phenomena of quantum mechanics in terms of a more fundamental description of nature that is more in line with the rules of classical physics. Many types of Bell test have been performed in physics laboratories, often with the goal of ameliorating problems of experimental design or set-up that could in principle affect the validity of the findings of earlier Bell tests. This is known as "closing loopholes in Bell test experiments". In a novel experiment conducted in 2016, over 100,000 volunteers participated in an online video game that used human choices to produce the data for researchers conducting multiple independent tests across the globe.
  • 5.4K
  • 29 Nov 2022
Topic Review
Enchanta
Enchanta /ɛnˈtʃɑːntɑː/ (Enchan /ɛnˈtʃɑːn/ in the 2016 series) is a constructed language spoken by the denizens of Encantadia, known as Encantado(s)/Encantada(s) or Diwata (fairies). It was initially created by Suzette Doctolero for the Philippines fantasy television drama saga Encantadia, which aired on GMA Network in 2005, and was later used in the show's sequels, Etheria: Ang Ikalimang Kaharian ng Encantadia and Encantadia: Pag-ibig Hanggang Wakas. The source material of the language appears to have been derived from Philippine languages (particularly Tagalog) and Romance languages. It has its own script, Enchan, which appears to be based on Baybayin. Three songs in the language are written by Doctolero, namely "Asshenti (Love song)", "Hade!! (Etheria theme song)", and "Ivo (Lireo national anthem)", which are all sung by Bayang Barrios for the sequel Etheria in 2006.
  • 5.4K
  • 07 Nov 2022
Topic Review
Analysis of Business Efficiency
Measuring efficiency and identifying the sources of potential inefficiency in particular are very important steps in improving the competitive position of the enterprises in their continuous development, sustainability, overall behavior in the current corporate environment and security aspects. 
  • 5.4K
  • 28 Jan 2022
Topic Review
Human Sex Ratio
In anthropology and demography, the human sex ratio is the ratio of males to females in a population. More data are available for humans than for any other species, and the human sex ratio is more studied than that of any other species, but interpreting these statistics can be difficult. Like most sexual species, the sex ratio in humans is close to 1:1. In humans, the natural ratio between males and females at birth is slightly biased towards the male sex, being estimated to be about 1.05 or 1.06 or within a narrow range from 1.03 to 1.06 males/per female born. Sex imbalance may arise as a consequence of various factors including natural factors, exposure to pesticides and environmental contaminants, war casualties, sex-selective abortions, infanticides, aging, gendercide and problems with birth registration. The sex ratio for the entire world population is 100 males to 100 females (2021 est.). Human sex ratios, either at birth or in the population as a whole, are reported in any of four ways: the ratio of males to females, the ratio of females to males, the proportion of males, or the proportion of females. If there are 108,000 males and 100,000 females the ratio of males to females is 1.080 and the proportion of males is 51.9%. Scientific literature often uses the proportion of males. This article uses the ratio of males to females, unless specified otherwise.
  • 5.4K
  • 08 Oct 2022
Topic Review
Free Society
The term free society is used frequently by American libertarian theorists to denote a society in which their ideal political, legal and economic aims are in effect. In a theoretical free society, all individuals act voluntarily, having the freedom to obtain the power and resources to fulfill their own potential. Adlai Stevenson defined free societies as a society in which individuals find it "safe to be unpopular". Others, such as Chandran Kukathas, described a free society as dependent upon the "principle of freedom of association". Cindy Cohn has argued that the freedom to have a "private conversation" is "central to a free society". These interpretations can also be elaborated in terms of freedom of speech – if people have a right to express their views without fear of arrest, imprisonment, or physical harm. In a free society, individuals would organize in voluntary associations, including free market and communal societies. Individuals would gain more prosperity due to the lack of restrictions on trade and wealth creation.
  • 5.4K
  • 11 Oct 2022
Topic Review
Club of Rome
Founded in 1968 at Accademia dei Lincei in Rome, Italy, the Club of Rome consists of current and former heads of state, UN bureaucrats, high-level politicians and government officials, diplomats, scientists, economists, and business leaders from around the globe. It stimulated considerable public attention in 1972 with the first report to the Club of Rome, The Limits to Growth. Since 1 July 2008 the organization has been based in Winterthur, Switzerland.
  • 5.4K
  • 02 Nov 2022
Topic Review
Ti Nitrides and Ti Silicides
The diffusion of nitrogen into TiSi2 films of low electrical resistivity, deposited on complementary metal oxyde semiconductor (CMOS) and Schottky diodes components increases their performances. TiN acts as a good diffusion barrier, gate material, Schottky barrier contact...Both TiSi2 and TiN are synthesized in Ti films coated on Si wafers and processed in an expanding microwave plasma producing nitrogen species such as NHx...This process promotes the chemical reactions at the surface of the metal. The growth of both compounds give rise to two competing processes which are thermodynamically and kinetically controlled. Ti films, 250 nm thick, processed at 600°C for  30 min, only consist of TiSi2 crystallites and TiN of amorphous structure. TiN crystallizes at 800°C and grows at the expense of TiSi2 according to thermodynamic data. 
  • 5.4K
  • 30 Oct 2020
Topic Review
Normal Gravity Formula
Normal gravity formulas are mathematical expressions, with which the free-fall acceleration at a point in vicinity to the surface of the earth can be estimated. Along with the mass (known or predicted) of a body, the weight is calculated.
  • 5.4K
  • 10 Nov 2022
Topic Review
Uniaxial Tensile Test
Tensile testing, also known as tension testing, is a fundamental materials science and engineering test in which a sample is subjected to a controlled tension until failure. Properties that are directly measured via a tensile test are ultimate tensile strength, breaking strength, maximum elongation and reduction in area. From these measurements the following properties can also be determined: Young's modulus, Poisson's ratio, yield strength, and strain-hardening characteristics. Uniaxial tensile testing is the most commonly used for obtaining the mechanical characteristics of isotropic materials. Some materials use biaxial tensile testing. The main difference between these testing machines being how load is applied on the materials.
  • 5.4K
  • 07 Nov 2022
Topic Review
Climate Change and Russian Agriculture
Russian weather trends such as winter softening and increase in summer heat have a significant but opposite effect on yields. An interesting finding is a significant and mostly positive influence of global climatic variables, such as the CO2 concentration, El Niño and La Niña events on both harvests and yields. Although technological factors are the main drivers of growth in Russian agricultural performance over the past 20 years, we found a strong positive effect on yield and gross harvest only for mineral fertilizers. The influence of the other variables is mixed, which is mainly due to data quality and aggregation errors.
  • 5.4K
  • 24 Jan 2022
Topic Review
Early Flood Warning System
The early-warning model for flash floods is based on a hydrological and geomorphological concept connected to the river basin, with the principle that flash floods will only occur where there is a high potential risk and when rainfall exceeds the threshold. In the model used to build flash-floods risk maps, the parameters of the basin are analyzed and evaluated and the weight is determined using Thomas Saaty’s analytic hierarchy process (AHP). The flash-floods early-warning software is built using open source programming tools. With the spatial module and online processing, a predicted precipitation of one to six days in advance for iMETOS (AgriMedia—Vietnam) automatic meteorological stations is interpolated and then processed with the potential risk maps (iMETOS is a weather-environment monitoring system comprising a wide range of equipment and an online platform and can be used in various fields such as agriculture, tourism and services). The results determine the locations of flash floods at several risk levels corresponding to the predicted rainfall values at the meteorological stations. The system was constructed and applied to flash floods disaster early warning for Thuan Chau in Son La province when the rainfall exceeded the 150 mm/d threshold. The system initially supported positive decision-making to prevent and minimize damage caused by flash floods.
  • 5.4K
  • 27 Jan 2022
Topic Review
German Question
"The German Question" was a debate in the 19th century, especially during the Revolutions of 1848, over the best way to achieve a unification of all or most lands inhabited by Germans. From 1815 to 1866, about 37 independent German-speaking states existed within the German Confederation. The Großdeutsche Lösung ("Greater German solution") favored unifying all German-speaking peoples under one state, and was promoted by the Austrian Empire and its supporters. The Kleindeutsche Lösung ("Little German solution") sought only to unify the northern German states and did not include any part of Austria (either its German-inhabited areas or its areas dominated by other ethnic groups); this proposal was favored by the Kingdom of Prussia. The solutions are also referred to by the names of the states they proposed to create, Kleindeutschland and Großdeutschland ("Little Germany" and "Greater Germany"). Both movements were part of a growing German nationalism. They also drew upon similar contemporary efforts to create a unified nation state of people who shared a common ethnicity and language, such as the unification of Italy by the House of Savoy and the Serbian Revolution. During the Cold War, the term also referred to the matters pertaining to the division, and re-unification, of Germany.
  • 5.4K
  • 21 Nov 2022
Topic Review Peer Reviewed
Natural Disasters: Origins, Impacts, Management
Natural hazards are processes that serve as triggers for natural disasters. Natural hazards can be classified into six categories. Geophysical or geological hazards relate to movement in solid earth. Their examples include earthquakes and volcanic activity. Hydrological hazards relate to the movement of water and include floods, landslides, and wave action. Meteorological hazards are storms, extreme temperatures, and fog. Climatological hazards are increasingly related to climate change and include droughts and wildfires. Biological hazards are caused by exposure to living organisms and/or their toxic substances. The COVID-19 virus is an example of a biological hazard. Extraterrestrial hazards are caused by asteroids, meteoroids, and comets as they pass near earth or strike earth. In addition to local damage, they can change earth inter planetary conditions that can affect the Earth’s magnetosphere, ionosphere, and thermosphere. This entry presents an overview of origins, impacts, and management of natural disasters. It describes processes that have potential to cause natural disasters. It outlines a brief history of impacts of natural hazards on the human built environment and the common techniques adopted for natural disaster preparedness. It also lays out challenges in dealing with disasters caused by natural hazards and points to new directions in warding off the adverse impact of such disasters. 
  • 5.4K
  • 13 Apr 2022
Topic Review
Pathogenic Bacteria
Pathogenic bacteria are bacteria that can cause disease. This article focuses on the bacteria that are pathogenic to humans. Most species of bacteria are harmless and are often beneficial but others can cause infectious diseases. The number of these pathogenic species in humans is estimated to be fewer than a hundred. By contrast, several thousand species are part of the gut flora present in the digestive tract. The body is continually exposed to many species of bacteria, including beneficial commensals, which grow on the skin and mucous membranes, and saprophytes, which grow mainly in the soil and in decaying matter. The blood and tissue fluids contain nutrients sufficient to sustain the growth of many bacteria. The body has defence mechanisms that enable it to resist microbial invasion of its tissues and give it a natural immunity or innate resistance against many microorganisms. Pathogenic bacteria are specially adapted and endowed with mechanisms for overcoming the normal body defences, and can invade parts of the body, such as the blood, where bacteria are not normally found. Some pathogens invade only the surface epithelium, skin or mucous membrane, but many travel more deeply, spreading through the tissues and disseminating by the lymphatic and blood streams. In some rare cases a pathogenic microbe can infect an entirely healthy person, but infection usually occurs only if the body's defence mechanisms are damaged by some local trauma or an underlying debilitating disease, such as wounding, intoxication, chilling, fatigue, and malnutrition. In many cases, it is important to differentiate infection and colonization, which is when the bacteria are causing little or no harm. Caused by Mycobacterium tuberculosis bacteria, one of the diseases with the highest disease burden is tuberculosis, which killed 1.4 million people in 2019, mostly in sub-Saharan Africa. Pathogenic bacteria contribute to other globally important diseases, such as pneumonia, which can be caused by bacteria such as Streptococcus, Pneumococcus and Pseudomonas, and foodborne illnesses, which can be caused by bacteria such as Shigella, Campylobacter, and Salmonella. Pathogenic bacteria also cause infections such as tetanus, typhoid fever, diphtheria, syphilis, and leprosy. Pathogenic bacteria are also the cause of high infant mortality rates in developing countries. Most pathogenic bacteria can be grown in cultures and identified by Gram stain and other methods. Bacteria grown in this way are often tested to find which antibiotics will be an effective treatment for the infection. For hitherto unknown pathogens, Koch's postulates are the standard to establish a causative relationship between a microbe and a disease.
  • 5.4K
  • 07 Nov 2022
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