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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.
  • 4.5K
  • 23 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.
  • 4.5K
  • 08 Feb 2024
Topic Review
The Festival of Diwali: Its Origins and History
Diwali, the Festival of Lights, is one of India's most celebrated festivals, marked by joy, light, and a spirit of togetherness. Originating in ancient India, Diwali has grown beyond its religious roots to become a global celebration symbolizing victory over darkness, ignorance, and evil. While traditionally associated with Hinduism and stories from the Ramayana, Diwali is also celebrated by Sikhs, Jains, and Buddhists, each community attaching its own significance and narratives to the festivities. This article traces the historical evolution of Diwali from its origins in agrarian societies to its current standing as a multicultural and global festival. It examines the religious and cultural stories associated with Diwali, the rituals and customs observed across different communities, and the festival’s role in fostering social cohesion. As Diwali has spread globally, it has taken on new meanings and variations, demonstrating the enduring appeal of this ancient festival in modern times.
  • 4.5K
  • 01 Nov 2024
Topic Review
Nasal Mucosa Injury
Nasal mucosa injury can be caused by trauma, radiotherapy, chronic infection such as sinusitis, and post sinus surgery. The rate of healing and its treatment are important in the recovery of patients especially in post sinus surgery, which introduces new injuries.
  • 4.5K
  • 28 Apr 2022
Topic Review
Fenbendazole Fever
Fenbendazole (FZ) is a benzimidazole carbamate drug with broad-spectrum antiparasitic activity in humans and animals. The mechanism of action of FZ is associated with microtubular polymerization inhibition and glucose uptake blockade resulting in reduced glycogen stores and decreased ATP formation in the adult stages of susceptible parasites. 
  • 4.5K
  • 10 Nov 2022
Topic Review
Fuzzy Logic Control for Refrigeration Systems
Logic fuzzy systems are based on the human ability to think, which has allowed controllers to adapt better to systems by finding an approximation to their real behavior.
  • 4.5K
  • 14 Mar 2022
Topic Review
Saudi Arabian Plants
The kingdom of Saudi Arabia (SA) ranks fifth in Asia in terms of area. It features broad biodiversity, including interesting flora, and was the historical origin of Islam. It is endowed with a large variety of plants, including many herbs, shrubs, and trees. Many of these plants have a long history of use in traditional medicine.
  • 4.5K
  • 13 Jan 2023
Topic Review Peer Reviewed
Inhabited Institutionalism
Inhabited Institutionalism is a meso-level theoretical approach for evaluating the recursive relationships among institutions, social interactions, and organizations. This theoretical framework offers organizational scholars a multi-faceted consideration of coupling configurations that highlight how institutional processes are maintained, challenged, and transformed without reverting to nested yet binary arguments about individual agency and structural conditions.
  • 4.5K
  • 18 Aug 2022
Topic Review
Plant-Based Milk Production
Growing concerns about the environmental impacts, healthiness, and ethical implications of eating animal-based products, such as meat, eggs, and milk, has led to an increase in demand for plant-based alternatives.  Plant-based milk substitutes can be created using two main approaches. First, certain oil-rich plant tissues (such as almonds, cashews, coconut flesh, flaxseeds, or soy beans) can be converted into colloidal suspensions using size-reduction and isolation techniques (such as soaking, grinding, enzyme-treatment, filtration, and centrifugation).  Second, plant-based oils (such as corn, flaxseed soybean, or sunflower oil) can be homogenized with water in the presence of plant-based proteins (such as pea, legume, or soy proteins), polysaccharides (gum arabic or beet pectin), phospholipids (such as soy or sunflower lecithin), or saponins (such as quillaja saponin) to create an oil-in-water emulsion with similar characteristics to bovine milk.   
  • 4.5K
  • 28 Oct 2020
Topic Review Peer Reviewed
Fungal Secondary Metabolism
Fungal secondary metabolites (SMs) comprise a vast collection of compounds expendable for these organisms under laboratory conditions. They exhibit enormous chemical diversity, and usually belong to four major families: terpenoids, polyketides, non-ribosomal peptides, or a combination of the last two. Their functions are very diverse and are normally associated with a greater fitness of the producing fungi in their environment, which often compete with other microorganisms or interact with host plants. Many SMs have beneficial applications, e.g., as antibiotics or medical drugs, but others, known as mycotoxins, are harmful to health.
  • 4.5K
  • 13 Apr 2022
Topic Review
Kerb Construction
Concrete kerbs can be prepared by precast and cast in situ methods. The precast concrete kerbs can be manufactured by conventional (using a vibrator), dry-pressed and wet-pressed methods and can be installed in almost all weather conditions. Possible rainfall, temperatures and sunlight hours are considered in casting in situ kerbs, and they are more labour-intensive compared to the precast variations. However, cast in situ kerb can better handle sudden changes of direction. There is no study found comparing different aspects of in situ casting and precast kerb. Both types of concrete kerb are suggested for construction by all authorities, such as the Austroads and AASHTO. The precast kerbs require manual placement and have been a major source of workplace injury in the United Kingdom. Past studies have suggested that the use of special lifting equipment (such as vacuum lifters, lifting clamps or stone magnets), reduction in kerb section length, reduction in kerb foundation depth, use of a lightweight or hollow concrete section or other lightweight materials, such as polymer, can reduce the likelihood of such workplace injuries and may also lead to quicker construction as well as better construction quality.
  • 4.5K
  • 28 Mar 2022
Topic Review
Building-Integrated Photovoltaics in Singapore
Building-integrated photovoltaics (BIPVs) represent an effective technology to attain zero energy buildings (ZEBs) via solar energy use. A BIPV system can seamlessly integrate PV modules into external building surfaces, such as walls, roofs, shading devices, and decorative components. Moreover, it can generate clean energy. From an environmental and economic perspective, PV energy generation provides more advantages than fossil fuel-based energy generation. First, in contrast to the limited storage of fossil fuels, the solar radiation reaching the Earth’s surface every day contains 10,000 times the energy requirements of humans on a daily basis. Second, the manufacturing process of PV modules produces only a small amount of carbon dioxide (20–30 g carbon dioxide equivalent (CO2e/kWh)).
  • 4.5K
  • 30 Aug 2022
Topic Review
Abuse of Power
Abuse of power or abuse of authority, in the form of "malfeasance in office" or "official abuse of power", is the commission of an unlawful act, done in an official capacity, which affects the performance of official duties. Malfeasance in office is often a just cause for removal of an elected official by statute or recall election. Officials who utilize abuse of power are often those who exploit the ability to use corruption in their advantage. In the United States, abuse of power has been cited in the impeachment of at least five federal officials. Two of these (Judge George English and President Richard Nixon) resigned before their trial in the Senate could take place, and two others were acquitted by the Senate. The two Senate impeachment trials of President Donald Trump concluded with the president being found not guilty both times. At the state level, Governor Rod Blagojevich of Illinois was impeached and unanimously removed from office by the Illinois Senate in 2009 for offenses including abuse of power.
  • 4.5K
  • 16 Nov 2022
Topic Review
Cocaine
Cocaine is one of the most consumed stimulants throughout the world, as official sources report. It is a naturally occurring sympathomimetic tropane alkaloid derived from the leaves of Erythroxylon coca, which has been used by South American locals for millennia. Cocaine can usually be found in two forms, cocaine hydrochloride, a white powder, or ‘crack’ cocaine, the free base. 
  • 4.5K
  • 27 Apr 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. 
  • 4.5K
  • 07 Dec 2022
Biography
Mikhail Leonidovich Gromov
Mikhail Leonidovich Gromov (also Mikhael Gromov, Michael Gromov or Mischa Gromov; Russian: Михаи́л Леони́дович Гро́мов; born 23 December 1943) is a Russian-French mathematician known for his work in geometry, analysis and group theory. He is a permanent member of IHÉS in France and a Professor of Mathematics at New York University. Gromov has won several prizes, includ
  • 4.5K
  • 29 Nov 2022
Topic Review
Dimensionality of materials
As generally known dimensionality of materials is a crucial factor to determine functions and properties of the materials. In addition to zero-dimensional, one-dimensional, three-dimensional, and further integrated functional materials, various two-dimensional materials have been paid special attention. Two-dimensional materials have their unique electronic propertiesand play important roles in interfacial sciences.
  • 4.5K
  • 12 Aug 2021
Topic Review
Mean Field Theory
In physics and probability theory, mean-field theory (aka MFT or rarely self-consistent field theory) studies the behavior of high-dimensional random (stochastic) models by studying a simpler model that approximates the original by averaging over degrees of freedom. Such models consider many individual components that interact with each other. In MFT, the effect of all the other individuals on any given individual is approximated by a single averaged effect, thus reducing a many-body problem to a one-body problem. The main idea of MFT is to replace all interactions to any one body with an average or effective interaction, sometimes called a molecular field. This reduces any multi-body problem into an effective one-body problem. The ease of solving MFT problems means that some insight into the behavior of the system can be obtained at a lower computational cost. MFT has since been applied to a wide range of fields outside of physics, including statistical inference, graphical models, neuroscience, artificial intelligence, epidemic models, queueing theory, computer network performance and game theory, as in the Quantal response equilibrium.
  • 4.5K
  • 03 Nov 2022
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.
  • 4.5K
  • 27 Oct 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.
  • 4.5K
  • 05 Jan 2021
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