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Topic Review
Parity
In quantum mechanics, a parity transformation (also called parity inversion) is the flip in the sign of one spatial coordinate. In three dimensions, it can also refer to the simultaneous flip in the sign of all three spatial coordinates (a point reflection): It can also be thought of as a test for chirality of a physical phenomenon, in that a parity inversion transforms a phenomenon into its mirror image. All fundamental interactions of elementary particles, with the exception of the weak interaction, are symmetric under parity. The weak interaction is chiral and thus provides a means for probing chirality in physics. In interactions that are symmetric under parity, such as electromagnetism in atomic and molecular physics, parity serves as a powerful controlling principle underlying quantum transitions. A matrix representation of P (in any number of dimensions) has determinant equal to −1, and hence is distinct from a rotation, which has a determinant equal to 1. In a two-dimensional plane, a simultaneous flip of all coordinates in sign is not a parity transformation; it is the same as a 180° rotation. In quantum mechanics, wave functions that are unchanged by a parity transformation are described as even functions, while those that change sign under a parity transformation are odd functions.
  • 4.2K
  • 10 Nov 2022
Topic Review
Bone Tissues
Osseous tissue is a kind of hard connective tissue, which is also composed of cells, fibers and matrix. The fibers are bone glue fibers (the same as collagen fibers), and the matrix contains a large amount of solid inorganic salts.
  • 4.2K
  • 13 Sep 2021
Topic Review
2014 Taiwan Food Scandal
The 2014 Taiwan food scandal refers to a series of food safety incidents in Taiwan that came to light in 2014. Adulteration of cooking oil with recycled waste oil and animal feed oil was discovered in September 2014. Despite coming to light only in 2014, mass food adulteration by Taiwanese food conglomerates, however, has been suppressed for decades, and the food safety crisis has been among the reasons for the electoral defeat of the Kuomintang in late 2014. At least 1,256 businesses were affected in the gutter oil scandal. In November 2014, it was found that dried tofu products (a.k.a. dougan 豆乾) have been adulterated with an industrial dye, methyl yellow (a.k.a. dimethyl), for some 20 years. In December 2014, it was furthermore found that even regular non-dyed tofu has been found contaminated with carcinogens, resulting in over 25,000 kg recalled.
  • 4.2K
  • 28 Nov 2022
Topic Review
Online Reviews
Online reviews, also referred to as electronic word of mouth (eWOM) or user-generated content (UGC), are all similar concepts with minor differences. eWOM is all electronic communications between producers and consumers and between consumers themselves: emails, websites, consumer review sites, blogs, virtual communities, chat rooms, newsgroups, and instant messaging. UGC is data generated online by consumers, e.g., text (consumer reviews and blogs) and picture data.
  • 4.2K
  • 09 Dec 2020
Topic Review
Gowind-Class Corvette
The Gowind design is a family of steel monohull corvettes developed since 2006 by France 's Naval Group, formerly known as DCNS, to conduct missions in littoral zone such as anti-submarine warfare (ASW). The Gowind family includes vessels with lengths from 85 m to 102 m and displacement from 1,000 t to 2,500 t. The Gowind design can deploy Unmanned Aerial Vehicles (UAVs), Unmanned Surface Vehicles (USVs) and Underwater Unmanned Vehicles (UUVs). An aft deck has been provided allowing for a 10-ton class helicopter or Unmanned Aerial Vehicle (UAV) operations. The platform's weapon system consists of a multi-functional radar and MICA SAM. It is armed with Exocet anti ship missiles. The propulsion system is based on Combined Diesel and Diesel (CODAD) and includes water-jets for improved maneuverability in shallow waters and high-speed performance. There is no funnel (smokestack) on these ships. The radar and other sensors are mounted on a single central mast thus allowing 360-degree view. Naval Group offers two variants of the design: Gowind 1000 and Gowind 2500.
  • 4.2K
  • 02 Dec 2022
Topic Review
Chemical Depolymerization Methods of Poly(ethylene terephthalate)
The significant amount of waste generated by poly(ethylene terephthalate) (PET) requires the development of a recycling process chain in which chemical recycling plays an important role. On the one hand, it allows the depolymerization of degraded plastics that do not meet the quality requirements to be used in mechanical recycling, and on the other hand, provides an opportunity to process cheap waste and obtain products with greater added value. It can be widely used in the recycling of both packaging plastics and textiles, or other waste generated with PET.
  • 4.2K
  • 12 Oct 2023
Topic Review
Fat-tailed Gerbil
The fat-tailed gerbil (Pachyuromys duprasi), also called the duprasi gerbil, is a rodent belonging to subfamily Gerbillinae. It is the only member of the genus Pachyuromys. These rodents are the most docile species of the gerbil subfamily. They have fluffy and soft fur. Fat-tailed gerbils have been available on the pet market for decades, but in the 21st century breeders can be hard to find. They are sometimes considered as pocket pets. Other common English names are: fat-tailed jird, fat-tailed rat, and beer mat gerbil. Names in other languages are: abu lya (أبو ليه) in Egyptian Arabic, and adhal alyan (عضل أليان) in Standard Arabic, souris à grosse queue (French), Fettschwanzrennmaus (German), fedthale mus (Danish), rasvahäntägerbiili (Finnish), and dikstaartgerbil (Dutch).
  • 4.2K
  • 08 Oct 2022
Topic Review
Consumption
Consumption is a fundamental economic and sociological concept that plays a pivotal role in shaping individual lifestyles, societal structures, and global economies. It refers to the utilization of goods and services by individuals or households to satisfy their needs and wants. This multifaceted phenomenon encompasses a wide range of activities, from the basic necessities of daily life to the acquisition of luxury items, and it has profound implications for various aspects of society.
  • 4.2K
  • 25 Jan 2024
Topic Review
The Perry High/Scope Preschool Program: A Critique
Early Childhood Education programs aim at preventing educational delays associated with socio-ethnic disadvantage in the home environment of young children. Advocates claim that such programs can be effective, provided they are of high quality. Despite the investment of enormous budgets, the educational gap between socio-economically deprived families and their wealthier counterparts is still widening. The question therefore is justified whether these claims are warranted. This article focuses on the internal and external validity of the most cited preschool program, the High/Scope Perry Preschool Project, which was carried out between 1962 and 1967 in one school in Ypsilant, MI. Are the program's effects as reported by, e.g. Lawrence Schweinhart and James Heckman, reliable and valid? And is it really possible to generalize the findings of this so-called model program to other programs, target groups, settings and conditions, as is being claimed?
  • 4.2K
  • 21 Aug 2023
Topic Review
Pranami Sampraday
Pranami Sampradaya is a community that believes in the Supreme Truth God "Rajji".
  • 4.2K
  • 11 Oct 2022
Topic Review
Empowerment
Empowerment is the degree of autonomy and self-determination in people and in communities. This enables them to represent their interests in a responsible and self-determined way, acting on their own authority. It is the process of becoming stronger and more confident, especially in controlling one's life and claiming one's rights. Empowerment as action refers both to the process of self-empowerment and to professional support of people, which enables them to overcome their sense of powerlessness and lack of influence, and to recognize and use their resources. As a term, empowerment originates from American community psychology and is associated with the social scientist Julian Rappaport (1981). However, the roots of empowerment theory extend further into history and are linked to Marxist sociological theory. These sociological ideas have continued to be developed and refined through Neo-Marxist Theory (also known as Critical Theory). In social work, empowerment forms a practical approach of resource-oriented intervention. In the field of citizenship education and democratic education, empowerment is seen as a tool to increase the responsibility of the citizen. Empowerment is a key concept in the discourse on promoting civic engagement. Empowerment as a concept, which is characterized by a move away from a deficit-oriented towards a more strength-oriented perception, can increasingly be found in management concepts, as well as in the areas of continuing education and self-help.
  • 4.2K
  • 15 Nov 2022
Topic Review
Pharmacological Update Properties of Aloe Vera Active Constituents
Aloe vera (Aloe barbadensis Miller, family Xanthorrhoeaceae) is a perennial green herb with bright yellow tubular flowers that is extensively distributed in hot and dry areas of North Africa, the Middle East of Asia, the Southern Mediterranean, and the Canary Islands.  Aloe vera has been traditionally used to treat skin injuries (burns, cuts, insect bites, and eczemas) and digestive problems because its anti-inflammatory, antimicrobial, and wound healing properties. 
  • 4.2K
  • 27 Jul 2022
Topic Review
Pentacene
Pentacene is a polycyclic aromatic hydrocarbon consisting of five linearly-fused benzene rings. This highly conjugated compound is an organic semiconductor. The compound generates excitons upon absorption of ultra-violet (UV) or visible light; this makes it very sensitive to oxidation. For this reason, this compound, which is a purple powder, slowly degrades upon exposure to air and light. Structurally, pentacene is one of the linear acenes, the previous one being tetracene (four fused benzene rings) and the next one being hexacene (six fused benzene rings). In August 2009, a group of researchers from IBM published experimental results of imaging a single molecule of pentacene using an atomic force microscope. In July 2011, they used a modification of scanning tunneling microscopy to experimentally determine the shapes of the highest occupied and lowest unoccupied molecular orbitals. In 2012, pentacene-doped p-terphenyl was shown to be effective as the amplifier medium for a room-temperature maser.
  • 4.2K
  • 12 Oct 2022
Topic Review
Maquis Du Vercors
The Maquis du Vercors was a rural group of the French Forces of the Interior (FFI) (maquis) that resisted the 1940–1944 German occupation of France in World War II. The Maquis du Vercors used the prominent scenic plateau known as the Massif du Vercors (Vercors Plateau) as a refuge. Initially the maquis carried out only sabotage and partisan operations against the Germans, but after the Normandy Invasion on 6 June 1944, the leadership of an army of about 4,000 maquis declared the "Free Republic of Vercors," raised the French flag, and attempted to create a conventional army to oppose the German occupation. The allies supported the maquis with parachute drops of weapons and by supplying teams of advisors and trainers, but the uprising was premature. In July 1944 as many as 10,000 German soldiers invaded the massif and killed more than 600 of the maquis, known as maquisards, and 200 civilians. It was German's largest anti-partisan operation in Western Europe during World War II. In August 1944, shortly after the battle for the Vercors, the area was liberated from German control by the American army allied with the FFI.
  • 4.2K
  • 20 Oct 2022
Topic Review
Green Chemistry Education
An important goal for sustainability education is to learn negotiation, problem solving and decision-making skills through discussions about ecological, social, economic, and ethical principles concerning local and global responsibility in their own life. Through memorable, experiential, and active processes, students learn to discuss their own value selection and to evaluate phenomena and sources of information critically. In this article, we aim to identify suitable pedagogical approaches to teaching and learning green chemistry among college students and preservice teachers by examining the teaching methods that have been used to promote green chemistry education (GCE) and how these methods have supported green chemistry learning (GCL).
  • 4.2K
  • 11 Nov 2020
Topic Review Peer Reviewed
Digital Literacy and Electronic Business
Digital literacy is a term that traditionally describes the extent to which a person is able to use interactive digital devices for living and working, such as computers and smartphones, as well as services delivered through these devices. The advent of the digital society at large and electronic business, specifically in the past decades, has broadened the use of digital devices beyond the isolated uses of working and simple communication; this advent has created digital ecosystems in which workers and consumers are embedded to various degrees, such as social media platforms or integrated shopping and media platforms. This embedding implies that a traditional, narrow notion of digital literacy needs to be extended and made more precise. For this purpose, we use the related notions of digital dexterity, digital proficiency and digital awareness. The term digital dexterity describes the extent to which an individual can handle or operate digital devices or services from a physical perspective. The term digital proficiency describes the extent to which an individual can use digital means to effectively and efficiently facilitate their living and working. The term digital awareness describes the extent to which individuals can understand what their position in digital ecosystems is, including the opportunities and threats of participating in these ecosystems. Digital literacy in the modern, broad interpretation is then the combination of digital dexterity, digital proficiency and digital awareness.
  • 4.2K
  • 13 Apr 2022
Topic Review
Lazarus
Lazarus is a free cross-platform visual integrated development environment (IDE) for rapid application development (RAD) using the Free Pascal compiler. Its goal is to provide an easy-to-use development environment for programmers developing with the Object Pascal language, which is as close as possible to Delphi. Software developers use Lazarus to create native-code console and graphical user interface (GUI) applications for the desktop, and also for mobile devices, web applications, web services, visual components and function libraries for a number of different platforms, including Mac, Linux and Windows. A project created by using Lazarus on one platform can be compiled on any other one which Free Pascal compiler supports. For desktop applications a single source can target Mac OS, Linux, and Windows, with little or no modification. An example is the Lazarus IDE itself, created from a single code base and available on all major platforms including the Raspberry Pi.
  • 4.2K
  • 17 Oct 2022
Topic Review
Atmospheric-pressure Chemical Ionization
Atmospheric pressure chemical ionization (APCI) is an ionization method used in mass spectrometry which utilizes gas-phase ion-molecule reactions at atmospheric pressure (105 Pa), commonly coupled with high-performance liquid chromatography (HPLC). APCI is a soft ionization method similar to chemical ionization where primary ions are produced on a solvent spray. The main usage of APCI is for polar and relatively less polar thermally stable compounds with molecular weight less than 1500 Da. The application of APCI with HPLC has gained a large popularity in trace analysis detection such as steroids, pesticides and also in pharmacology for drug metabolites.
  • 4.2K
  • 01 Dec 2022
Topic Review
Bismuth Ferrite
Bismuth ferrite was first discovered to harness its ferroelectric and magnetoelectric properties; the bulk BFO prepared in the 1960s–1970s were marred with high conductivity and secondary phases, which resulted in the loss of motivation over the years. It was not until the early 2000s that the research in single crystals, high-quality BFO thin films, and ceramics brought back researchers into BFO. It is an ABO3 type perovskite compound that crystalizes into the rhombohedral R3c group, hence possessing multiferroic properties due to its noncentrosymmetric nature. In ABO3, perovskite A is Bismuth (Bi) and occupies the corner of the perovskite unit cell, B is iron (Fe), the central atom with an oxygen octahedral arrangement. There is a tilting of oxygen octahedral, which doubles the pseudocubic unit cell giving rhombohedral unit cell. There is an equivalence between pseudocubic unit cell, rhombohedral and hexagonal unit cell representation and hence Figure 2 gives the hexagonal representation. The ferroelectric Curie temperature (TC) of BFO is as high as ~1103 K and antiferromagnetic Neel temperature (TN) is ~643 K. It exhibits a weak net magnetization as the G- type magnetic ordering with an incommensurate cycloidal spin structure having a periodicity of 62 nm. The chemical substitution of A and B sites are considered as one of the alternatives for enhancing the net magnetization via disruption of the cycloidal chain
  • 4.2K
  • 04 Feb 2023
Topic Review
Ursus (Genus)
Ursus is a genus in the family Ursidae (bears) that includes the widely distributed brown bear, the polar bear, the American black bear, and the Asian black bear. The name is derived from the Latin ursus, meaning bear.
  • 4.2K
  • 01 Dec 2022
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