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Topic Review
Power-System Protection
Power-system protection is a branch of electrical power engineering that deals with the protection of electrical power systems from faults through the disconnection of faulted parts from the rest of the electrical network. The objective of a protection scheme is to keep the power system stable by isolating only the components that are under fault, whilst leaving as much of the network as possible still in operation. Thus, protection schemes must apply a very pragmatic and pessimistic approach to clearing system faults. The devices that are used to protect the power systems from faults are called protection devices.
  • 4.4K
  • 16 Nov 2022
Topic Review
Agarwood
Agarwood, popularly known as oudh or gaharu, is a fragrant resinous wood of high commercial value, traded worldwide and primarily used for its distinctive fragrance in incense, perfumes, and medicine. This fragrant wood is created when Aquilaria trees are wounded and infected by fungi, producing resin as a defense mechanism. The depletion of natural agarwood caused by overharvesting amidst increasing demand has caused this fragrant defensive resin of endangered Aquilaria to become a rare and valuable commodity. Given that instances of natural infection are quite low, artificial induction, including biological inoculation, is being conducted to induce agarwood formation.
  • 4.4K
  • 06 Jun 2022
Topic Review
Power
In physics, power is the amount of energy transferred or converted per unit time. In the International System of Units, the unit of power is the watt, equal to one joule per second. In older works, power is sometimes called activity. Power is a scalar quantity. Power is related to other quantities; for example, the power involved in moving a ground vehicle is the product of the traction force on the wheels and the velocity of the vehicle. The output power of a motor is the product of the torque that the motor generates and the angular velocity of its output shaft. Likewise, the power dissipated in an electrical element of a circuit is the product of the current flowing through the element and of the voltage across the element.
  • 4.4K
  • 31 Oct 2022
Topic Review
Social Closure
Social closure refers to the process by which groups or social categories seek to establish and maintain boundaries to protect their privileged position and restrict access to resources, opportunities, or social status. This phenomenon involves mechanisms such as exclusion, discrimination, or credentialism, aimed at preserving the advantages of certain groups while limiting the mobility and opportunities of others. Social closure can manifest in various domains, including education, employment, and social institutions, contributing to social stratification and inequality within societies.
  • 4.4K
  • 08 Feb 2024
Topic Review
Glycogen Storage Diseases
Glycogen storage diseases (GSDs) are metabolic disorders of glycogen metabolism. In aggregate, GSDs are not considered rare diseases, but every individual type are. The overall estimated GSD incidence is 1 case per 20,000-43,000 live births, and a prevalence of 1:100,000 is considered for main types (including I, II, II, V and IX). There are 19 types which are classified by enzyme deficiency and affected tissue. Most of them are inherited in an autosomal recessive manner, except for one X-linked GSDIX and Danon subtypes. Disorders related with creation, deposits and degradation of glycogen, may primarily affect the liver (hepatic GSDs), the muscles (muscle GSDs), or in a multiorganic manner (mainly Pompe). The common characteristic of all types of GSDs is the alteration of some step in glycogenolysis/glycolysis pathway, as can be seen in figures 1a and 1b.
  • 4.4K
  • 13 May 2021
Topic Review
Salt Bridges investigated by NMR
Salt bridges are interactions, electrostatic combined with hydrogen bonding, between oppositely charged residues, typically carboxylic acid anions and ammonium ions, provided they are close together.  For an illustration see Fig. 1. Salt bridges are of particular interest in proteins and other biomolecules.  In the present contribution salt bridges are investigated by means of 1H chemical shifts, determination of pKa values and deuterium isotope effect on 15N and 1H chemical shifts.  In the latter case model compounds like ammonium ions are also investigated and the use of deuterium isotope effects on chemical shifts are supported by Density Functional Theory (DFT) calculations.  The use of isotope effects on chemical shifts enables a distinction between salt bridges observed in the solid state by X-ray diffraction and those actually present in solution.
  • 4.4K
  • 27 Oct 2020
Topic Review
Augmented Humanity
Augmented humanity is a human–computer integration technology that proposes to improve capacity and productivity by changing or increasing the normal ranges of human function, through the restoration or extension of human physical, intellectual and social capabilities.
  • 4.4K
  • 07 Feb 2022
Topic Review Peer Reviewed
Organizational Justice: Typology, Antecedents and Consequences
Organizational Justice is an individual’s perception that events, actions, or decisions within an organization adhere to a standard of fairness. Justice researchers have categorized justice into four types, differentiated by how fairness is evaluated by employees: distributive, procedural, interpersonal, and informational justice. Organizational justice perceptions have consequences for the employee and the organization: increasing job satisfaction, commitment, and trust; and decreasing turnover, counterproductive work behaviors, and even workplace violence. Contemporary organizational justice research seeks to understand how to restore justice after an injustice has occurred. 
  • 4.4K
  • 08 Jul 2022
Topic Review
Techniques Involved in Plantlet Generation
Ornamentals come in a variety of shapes, sizes, and colors to suit a wide range of climates, landscapes, and gardening needs. Compared to demand, a shortage of plant materials and diversity force the search for solutions for their constant acquisition and improvement to increase their commercial value, respectively. In vitro cultures are a suitable solution to meet expectations using callus culture, somatic embryogenesis, protoplast culture, and the organogenesis of protocorm-like bodies; many of these techniques are commercially practiced. Factors such as culture media, explants, carbohydrates, plant growth regulators, and light are associated with the success of in vitro propagation. Techniques, especially embryo rescue and somatic hybridization, are widely used to improve ornamentals. The development of synthetic seed allows season-independent seed production and preservation in the long term. Despite the advantages of propagation and the improvement of ornamentals, many barriers still need to be resolved. In contrast to propagation and crop developmental studies, there is also a high scope for molecular studies, especially epigenetic changes caused by plant tissue culture of ornamentals. 
  • 4.4K
  • 07 Dec 2022
Topic Review
Access Economy
The access economy is a business model where goods and services are traded on the basis of access rather than ownership: it refers to renting things temporarily rather than selling them permanently. The term arose as a correction to the term sharing economy because major players in the sharing economy, such as Airbnb, Zipcar, and Uber, are commercial enterprises whose businesses do not involve any sharing. This model uses a technology platform, often accessed via mobile phone, to connect suppliers willing to rent assets (e.g., apartments for rent or cars for transportation services) with consumers. This movement was worth around $26 billion a year in 2015. The number of persons involved in the access economy is not easily measured. The "access economy" or "on-demand economy" poses regulatory and political challenges, such as: defining the nature of the employment relationship; designing regulations to safeguard parties to these transactions; the loss of taxes and corporate access that results from moving away from small locally owned companies to large remote technology companies; and the bypassing of local regulations (such as the requirement for taxi drivers to provide wheelchair vans, or provide drivers 24-7).
  • 4.4K
  • 04 Nov 2022
Topic Review
Life Cycle Assessment of State-of-the-Art Steel Production Routes
Using the life cycle assessment (LCA) methodology, the impacts of the primary steel production via the blast furnace route and the scrap-based secondary steel production via the electric arc furance (EAF) route are assessed. Methodological as well as technical differences are analysed and their impacts on the results.
  • 4.4K
  • 08 Nov 2022
Topic Review
Smart Libraries
With the rapid development of artificial intelligence (AI) and Internet-of-Things (IoT), thousands of smart devices can be interconnected with each other. A series of innovative concepts have emerged and penetrated into all aspects of human life, e.g., “Smarter Planet”, “Smart City”, “Smart Community”, and “Smart Campus”. As a key and indispensable field, librarianship has become a convenient scenario aided by AI and IoT. Distinctive advanced AI-based approaches applied in libraries include, but are not limited to, natural language processing (NLP), deep learning (DL), recommender systems, machine vision, and smart acquisition.
  • 4.4K
  • 19 Apr 2022
Topic Review
Multi-Drug Resistance
Multidrug-resistance is a long debated term. Since 1980 it was used to imply the resistance of a microorganism to multiple pharmaceutical agents, without the number or types of antimicrobials being specified.Currently, the most widely accepted definition of multidrug-resistant (MDR) bacteria include a lack of susceptibility in three or more antimicrobial categories active against the isolated microorganism.
  • 4.4K
  • 27 Aug 2020
Topic Review
Bryophyllum sp.
The subgenus Bryophyllum belongs to genus Kalanchoe (Crassulaceae family) and includes about 25 plant species native to Madagascar, which are widely used in traditional medicine in vast regions throughout Africa, Asia and South Africa. Different formulations from bryophyllum (this term is proposed to be the common name to collectively refer to these species) have been employed for the treatment of several ailments, including infections, gynecological disorders, and chronic diseases, such as diabetes, neurological and neoplastic diseases. Two major families of secondary metabolites have been reported as responsible for these bioactivities: phenolic compounds and bufadienolides. These compounds are found in limited amounts in plants because they are biosynthesized in response to different biotic and abiotic stresses. Therefore, novel approaches should be undertaken with the aim of achieving the phytochemical valorization of Bryophyllum sp., allowing a sustainable production that prevents from a massive exploitation of wild plant resources. This review focuses on the study of phytoconstituents reported on bryophyllum; the application of plant tissue culture methodology as a reliable tool for the valorization of bioactive compounds; and the application of machine learning technology to model and optimize the full phytochemical potential of bryophyllum. As a result, bryophyllum species can be considered as a promising source of plant bioactive compounds, with enormous antioxidant and anticancer potential, which could be used for their large-scale biotechnological exploitation in cosmetic, food, and pharmaceutical industries.
  • 4.4K
  • 05 Jan 2021
Topic Review
Solar Tree
A solar tree is a structure incorporating solar energy technology on a single pillar, like a tree trunk. It may be a solar artwork or a functional power generator.
  • 4.4K
  • 17 Oct 2022
Topic Review
Plant Cell Culture
The large-scale production of plant-derived secondary metabolites (PDSM) in bioreactors to meet the increasing demand for bioactive compounds for the treatment and prevention of degenerative diseases is nowadays considered an engineering challenge. Plant cell culture (PCC) is nowadays recognized as a promising, renewable, sustainable, and environmentally friendly alternative to obtain PDSM out of wild plants. PCC accounts for the virtues of whole-plant cultivation systems and offers significant advantages, such as controlled manufacture due to standardized environmental conditions, i.e., it is not seasonal dependent, makes use of low amounts of water, and pesticides and herbicides are not required, achieving better quality in the desired product.
  • 4.4K
  • 29 Dec 2021
Topic Review
F-X (Japan)
The F-X (unofficially called F-3) is a sixth-generation stealth fighter in development for the Japan Air Self-Defense Force (JASDF). It is Japan's first domestically developed stealth fighter jet and will replace the Mitsubishi F-2 by the mid–2030's. Its development is to also bolster the nation's defense industry and potentially enter the international arms market amid Japan's change in defense posture. The F-X has been nicknamed the "Godzilla" fighter owing to its large size, as well as a nod to the popular Kaiju.
  • 4.4K
  • 17 Oct 2022
Topic Review
Hydrochar
Recently, due to the escalating usage of non-renewable fossil fuels such as coal, natural gas and petroleum coke in electricity and power generation, and associated issues with pollution and global warming, more attention is being paid to finding alternative renewable fuel sources. Thermochemical and hydrothermal conversion processes have been used to produce biochar and hydrochar, respectively, from waste renewable biomass. Char produced from the thermochemical and hydrothermal decomposition of biomass is considered an environmentally friendly replacement for solid hydrocarbon materials such as coal and petroleum coke. Unlike thermochemically derived biochar, hydrochar has received little attention due to the lack of literature on its production technologies, physicochemical characterization, and applications.
  • 4.4K
  • 23 Aug 2021
Topic Review
Photon
A photon (from grc φῶς, φωτός  'light') is an elementary particle that is a quantum of the electromagnetic field, including electromagnetic radiation such as light and radio waves, and the force carrier for the electromagnetic force. Photons are massless,[lower-alpha 1] so they always move at the speed of light in vacuum, 299792458 m/s (or about 186,282 mi/s). The photon belongs to the class of bosons. Like all elementary particles, photons are currently best explained by quantum mechanics, and exhibit wave–particle duality, their behavior featuring properties of both waves and particles. The modern photon concept originated during the first two decades of the 20th century with the work of Albert Einstein, who built upon the research of Max Planck. While trying to explain how matter and electromagnetic radiation could be in thermal equilibrium with one another, Planck proposed that the energy stored within a material object should be regarded as composed of an integer number of discrete, equal-sized parts. To explain the photoelectric effect, Einstein introduced the idea that light itself is made of discrete units of energy. In 1926, Gilbert N. Lewis popularized the term photon for these energy units. Subsequently, many other experiments validated Einstein's approach. In the Standard Model of particle physics, photons and other elementary particles are described as a necessary consequence of physical laws having a certain symmetry at every point in spacetime. The intrinsic properties of particles, such as charge, mass, and spin, are determined by gauge symmetry. The photon concept has led to momentous advances in experimental and theoretical physics, including lasers, Bose–Einstein condensation, quantum field theory, and the probabilistic interpretation of quantum mechanics. It has been applied to photochemistry, high-resolution microscopy, and measurements of molecular distances. Moreover, photons have been studied as elements of quantum computers, and for applications in optical imaging and optical communication such as quantum cryptography.
  • 4.4K
  • 23 Oct 2022
Topic Review
Corporate Social Responsibility Reporting
Corporate Social Responsibility (CSR) Reporting is an essential mechanism for ensuring the transparency and accountability of companies towards sustainability performance. To further promote that sustainable development agenda, CSR-related regulations and policies have emerged worldwide.
  • 4.4K
  • 22 Oct 2021
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