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Topic Review
Critical Minerals
Critical minerals are paramount to the successful deployment of low-carbon technologies in future transportation, defense, agriculture, healthcare, and infrastructure. They have a significant economic importance and their insecure supplies may hinder the development and industrial application of new technologies. An implementation of large quantities of minerals, in particular metals, into the clean energy transition will create new economic opportunities but also bring new challenges to energy security that could lead to unexpected dependencies on raw materials.
  • 3.9K
  • 30 Aug 2022
Topic Review
Mirroring (Psychology)
User:RMCD bot/subject notice Mirroring is the behavior in which one person unconsciously imitates the gesture, speech pattern, or attitude of another. Mirroring often occurs in social situations, particularly in the company of close friends or family. The concept often affects other individuals' notions about the individual that is exhibiting mirroring behaviors, which can lead to the individual building rapport with others. Mirroring is the subconscious replication of another person's nonverbal signals. This concept takes place in everyday interactions and often goes unnoticed by both the person enacting the mirroring behaviors as well as the individual who is being mirrored. The activation of mirror neurons takes place within the individual who begins to mirror another's movements and allows them a greater connection and understanding with the individual who they are mirroring, as well as allowing the individual who is being mirrored to feel a stronger connection with the other individual. Mirroring is distinct from conscious imitation under the premise that while the latter is a conscious, typically overt effort to copy another person, mirroring is unconsciously done during the act and often goes unnoticed. The display of mirroring often begins as early as infancy, as babies begin to mimic individuals around them and establish connections with particular body movements. The ability to mimic another person's actions allows the infant to establish a sense of empathy and thus begin to understand another person's emotions. The infant continues to establish connections with other individual's emotions and subsequently mirror their movements. Mirroring can establish rapport with the individual who is being mirrored, as the similarities in nonverbal gestures allow the individual to feel more connected with the person exhibiting the mirrored behavior. As the two individuals in the situation display similar nonverbal gestures, they may believe that they share similar attitudes and ideas as well. Mirror neurons react to and cause these movements, allowing the individuals to feel a greater sense of engagement and belonging within the situation.
  • 3.9K
  • 06 Oct 2022
Topic Review
Stokes Boundary Layer
In fluid dynamics, the Stokes boundary layer, or oscillatory boundary layer, refers to the boundary layer close to a solid wall in oscillatory flow of a viscous fluid. Or, it refers to the similar case of an oscillating plate in a viscous fluid at rest, with the oscillation direction(s) parallel to the plate. For the case of laminar flow at low Reynolds numbers over a smooth solid wall, George Gabriel Stokes – after whom this boundary layer is called – derived an analytic solution, one of the few exact solutions for the Navier–Stokes equations. In turbulent flow, this is still named a Stokes boundary layer, but now one has to rely on experiments, numerical simulations or approximate methods in order to obtain useful information on the flow. The thickness of the oscillatory boundary layer is called the Stokes boundary-layer thickness.
  • 3.9K
  • 28 Oct 2022
Topic Review
Different Definitions of Dyslexia
Defining dyslexia has still not reached a consensus. This uncertainty may explain why only one of the seven definitions proved satisfactory according to the four-level model. Today, dyslexia is a term that is commonly known and denotes an innate disposition leading to reading and/or writing difficulties. Medicine, linguistics, psychology, pedagogics, social sciences have been involved in assessing dyslexia from different angles.
  • 3.9K
  • 09 Nov 2022
Topic Review
Interfacial Polymerization Techniques for TFC/TFN
Here, we review various novel/modified interfacial polymerization (IP) techniques for the fabrication of polyamide (PA) thin film composite (TFC)/thin film nanocomposite (TFN) membranes in both pressure-driven and osmotically driven separation processes. Although conventional IP technique is the dominant technology for the fabrication of commercial nanofiltration (NF) and reverse osmosis (RO) membranes, it is plagued with issues of low membrane permeability, relatively thick PA layer and susceptibility to fouling, which limit the performance. Over the past decade, we have seen a significant growth in scientific publications related to the novel/modified IP techniques used in fabricating advanced PA-TFC/TFN membranes for various water applications. Novel/modified IP lab-scale studies have consistently, so far, yielded promising results compared to membranes made by conventional IP technique, in terms of better filtration efficiency (increased permeability without compensating solute rejection), improved chemical properties (crosslinking degree), reduced surface roughness and the perfect embedment of nanomaterials within selective layers. Furthermore, several new IP techniques can precisely control the thickness of the PA layer at sub-10 nm and significantly reduce the usage of chemicals.
  • 3.9K
  • 09 Mar 2021
Topic Review
Dexibuprofen
S-(+) enantiomer of ibuprofen (IBU) dexibuprofen (DXI) is known to be more potent than its R-(−) form and exhibits many advantages over the racemic mixture of IBU such as lower toxicity, greater clinical efficacy, and lesser variability in therapeutic effects. Moreover, DXI potential has been recently advocated to reduce cancer development and prevent the development of neurodegenerative diseases in addition to its anti-inflammatory properties. 
  • 3.9K
  • 23 Jun 2021
Topic Review
Spin
Spin is an intrinsic form of angular momentum carried by elementary particles, and thus by composite particles (hadrons) and atomic nuclei. Spin is one of two types of angular momentum in quantum mechanics, the other being orbital angular momentum. The orbital angular momentum operator is the quantum-mechanical counterpart to the classical angular momentum of orbital revolution and appears when there is periodic structure to its wavefunction as the angle varies. For photons, spin is the quantum-mechanical counterpart of the polarization of light; for electrons, the spin has no classical counterpart. The existence of electron spin angular momentum is inferred from experiments, such as the Stern–Gerlach experiment, in which silver atoms were observed to possess two possible discrete angular momenta despite having no orbital angular momentum. The existence of the electron spin can also be inferred theoretically from the spin–statistics theorem and from the Pauli exclusion principle—and vice versa, given the particular spin of the electron, one may derive the Pauli exclusion principle. Spin is described mathematically as a vector for some particles such as photons, and as spinors and bispinors for other particles such as electrons. Spinors and bispinors behave similarly to vectors: they have definite magnitudes and change under rotations; however, they use an unconventional "direction". All elementary particles of a given kind have the same magnitude of spin angular momentum, though its direction may change. These are indicated by assigning the particle a spin quantum number. The SI unit of spin is the same as classical angular momentum (i.e., N·m·s, J·s, or kg·m2·s−1). In practice, spin is given as a dimensionless spin quantum number by dividing the spin angular momentum by the reduced Planck constant ħ, which has the same dimensions as angular momentum, although this is not the full computation of this value. Very often, the "spin quantum number" is simply called "spin". The fact that it is a quantum number is implicit.
  • 3.9K
  • 27 Oct 2022
Topic Review
Biological Functions of Nitric Oxide
Nitric oxide (nitrogen monoxide) is a molecule and chemical compound with chemical formula of NO. In mammals including humans, nitric oxide is a signaling molecule involved in several physiological and pathological processes. It is a powerful vasodilator with a half-life of a few seconds in the blood. Standard pharmaceuticals such as nitroglycerine and amyl nitrite are precursors to nitric oxide. Low levels of nitric oxide production are typically due to ischemic damage in the liver. As a consequence of its importance in neuroscience, physiology, and immunology, nitric oxide was proclaimed "Molecule of the Year" in 1992. Research into its function led to the 1998 Nobel Prize for elucidating the role of nitric oxide as a cardiovascular signalling molecule.
  • 3.9K
  • 04 Nov 2022
Topic Review
Roof Plate in Neural Development
The roof plate is the most dorsal region of the neural tube. The Roof plate serves as an organizing center that controls proliferation and differentiation of dorsal interneurons. In addition, this region is involved in development of neural crest cells, which are the source of migratory neural crest cells. During early development of the spinal cord, roof plate cells secrete signaling molecules, such as Wnt and BMP family proteins, which regulate development of neural crest cells and dorsal spinal cord. After the dorso-ventral pattern is established, spinal cord dynamically changes its morphology. With this morphological transformation, the lumen of the spinal cord gradually shrinks to form the central canal. Accompanied by formation of the central canal, roof plate cells dramatically stretch along the dorso-ventral axis. During this stretching process, the tips of roof plate cells maintain contact with cells surrounding the shrinking lumen of the spinal cord, eventually exposed to the inner surface of the central canal. In this late stage of the spinal cord development, Wnt secreted by stretched roof plate cells regulates transformation of roof plate cells themselves and promotes proliferation of ependymal cells surrounding the central canal, including neural progenitor cells, in the spinal cord.
  • 3.9K
  • 05 Aug 2021
Topic Review
Phlegm Syndrome
Phlegm is defined as a viscous and turbid pathological factor that is formed due to an imbalance in body fluid in traditional East Asian medicine (TEAM) and accumulates in certain parts of the body as the form of condensation.
  • 3.9K
  • 12 Oct 2021
Topic Review
Synthesis of Conducting Polymers
Conductive polymers (CPs) are a class of organic compounds that belong to a large group of electrochemically active polymers. They have been actively studied for more than 40 years, beginning with the discovery of the conductive properties of halogen-substituted polyacetylene and the preparation of polypyrrole.
  • 3.9K
  • 26 Sep 2023
Topic Review
Marine Mammal
Marine mammals are aquatic mammals that rely on the ocean and other marine ecosystems for their existence. They include animals such as seals, whales, manatees, sea otters and polar bears. They do not represent a distinct taxon or systematic grouping, but rather have a polyphyletic relation due to convergent evolution, as in they do not have an immediate common ancestor. They are also unified by their reliance on the marine environment for feeding. Marine mammal adaptation to an aquatic lifestyle varies considerably between species. Both cetaceans and sirenians are fully aquatic and therefore are obligate water dwellers. Seals and sea-lions are semiaquatic; they spend the majority of their time in the water, but need to return to land for important activities such as mating, breeding and molting. In contrast, both otters and the polar bear are much less adapted to aquatic living. Their diet varies considerably as well; some may eat zooplankton, others may eat fish, squid, shellfish, sea-grass and a few may eat other mammals. While the number of marine mammals is small compared to those found on land, their roles in various ecosystems are large, especially concerning the maintenance of marine ecosystems, through processes including the regulation of prey populations. This role in maintaining ecosystems makes them of particular concern as 23% of marine mammal species are currently threatened. Marine mammals were first hunted by aboriginal peoples for food and other resources. Many were also the target for commercial industry, leading to a sharp decline in all populations of exploited species, such as whales and seals. Commercial hunting lead to the extinction of †Steller's sea cow, †sea mink, †Japanese sea lion and the †Caribbean monk seal. After commercial hunting ended, some species, such as the gray whale and northern elephant seal, have rebounded in numbers; conversely, other species, such as the North Atlantic right whale, are critically endangered. Other than hunting, marine mammals can be killed as bycatch from fisheries, where they become entangled in fixed netting and drown or starve. Increased ocean traffic causes collisions between fast ocean vessels and large marine mammals. Habitat degradation also threatens marine mammals and their ability to find and catch food. Noise pollution, for example, may adversely affect echolocating mammals, and the ongoing effects of global warming degrade arctic environments.
  • 3.9K
  • 21 Oct 2022
Topic Review
Wearable User Interface
Making a wearable robot is one of the most important research issues, not only in the bio-mimicking robotics area but also in the conventional robotics or haptics area. There are many advantages for using DEAs for wearable interfaces, such as their small size, flexibility, softness, and customizability. Many wearable haptic interfaces using Dielectric Elastomer Actuators such as tactile displays or vibrotactile displays were suggested from the previous researches. However, there are several challenges in the use of DEAs as actuators embedded into wearable devices such as high driving voltage and low output force compare to the motor based actuator. 
  • 3.9K
  • 01 Nov 2020
Topic Review
Nickel Laterite Deposit
Tectonic emplacement of variably serpentinized ultramafic host rock on land and subsequent chemical weathering under humid tropical to subtropical conditions results in the formation of nickel laterite deposits. Nickel laterites typically occur as weathering mantle over ophiolite complexes, as well as komatiites and layered complexes in Archean to Phanerozoic stable cratonic platforms.
  • 3.9K
  • 01 Apr 2022
Topic Review
High-explosive Anti-tank Warhead
A high-explosive anti-tank (HEAT) warhead is a type of shaped charge explosive that uses the Munroe effect to penetrate thick tank armor. The warhead functions by having the explosive charge collapse a metal liner inside the warhead into a high-velocity superplastic jet. This superplastic jet is capable of penetrating armor steel to a depth of seven or more times the diameter of the charge (charge diameters, CD) but is usually used to immobilize or destroy tanks. Due to the way they work, they do not have to be fired as fast as an armor piercing shell, allowing less recoil. Contrary to a widespread misconception (possibly resulting from the acronym HEAT), the jet does not melt its way through armor, as its effect is purely kinetic in nature. The HEAT warhead has become less effective against tanks and other armored vehicles due to the use of composite armor, explosive-reactive armor, and active protection systems which destroy the HEAT warhead before it hits the tank. While HEAT ammunition has become less effective against the composite armor found on MBTs from 1964 onward and today pose little threat to any modern tank, they are still deadly against lighter vehicles. In addition, air vehicles are also possible targets.
  • 3.9K
  • 01 Nov 2022
Topic Review
Visual Basic
User:RMCD bot/subject notice Visual Basic (also referred to as Classic Visual Basic) is a third-generation event-driven programming language from Microsoft known for its Component Object Model (COM) programming model first released in 1991 and declared legacy during 2008. Microsoft intended Visual Basic to be relatively easy to learn and use. Visual Basic was derived from BASIC and enables the rapid application development (RAD) of graphical user interface (GUI) applications, access to databases using Data Access Objects, Remote Data Objects, or ActiveX Data Objects, and creation of ActiveX controls and objects. A programmer can create an application using the components provided by the Visual Basic program itself. Over time the community of programmers developed third-party components. Programs written in Visual Basic can also make use of the Windows API, which requires external functions declarations. The final release was version 6 in 1998 (now known simply as Visual Basic). On April 8, 2008, Microsoft stopped supporting Visual Basic 6.0 IDE. The Microsoft Visual Basic team still maintains compatibility for Visual Basic 6.0 applications through its "It Just Works" program on supported Windows operating systems. In 2014, some software developers still preferred Visual Basic 6.0 over its successor, Visual Basic .NET. In 2014 some developers lobbied for a new version of the VB6 programming environment. In 2016, Visual Basic 6.0 won the technical impact award at The 19th Annual D.I.C.E. Awards. Visual Basic 6.0 was selected as the most dreaded programming language by respondents of Stack Overflow's annual developer survey in 2016, 2017, and 2018. A dialect of Visual Basic, Visual Basic for Applications (VBA), is used as a macro or scripting language within several Microsoft and ISV applications, including Microsoft Office.
  • 3.9K
  • 17 Nov 2022
Topic Review
Greek Old Calendarists
Greek Old Calendarists (Greek: Παλαιοημερολογίτες, Paleoimerologites), sometimes abbreviated as GOC ("Genuine Orthodox Christians"), are groups of Old Calendarist Orthodox Christians that remained committed to the traditional Orthodox practice and are not in communion with many other Orthodox churches such as the Orthodox Church of Greece, the Patriarchate of Constantinople, or the Church of Cyprus. The split began with a disagreement over the abandonment of the traditional church calendar (also called the Julian calendar) in preference to the adoption of the Revised Julian calendar which is similar to the papal Gregorian calendar but will pull ahead by one day in the year 2800 and over other liturgical reforms that were introduced.
  • 3.9K
  • 24 Nov 2022
Topic Review
3D Braiding Technology
3D braiding technologies enable the production of structures with complex geometry, which are often used for lightweight solutions, for example in automotive engineering. In addition, medical technology offers wide-ranging applications for 3D braiding technology. 3D braided structures are defined as those with yarns that intersect in all three spatial directions. 3D braiding processes allow the fiber orientation to be easily influenced, thus ensuring high strength and stiffness with reduced mass.
  • 3.9K
  • 25 Aug 2021
Topic Review
Molecular Dynamics Simulations
Molecular dynamics (MD) is a simulation technique that aims at deriving statements about the structural, dynamical, and thermodynamical properties of a molecular system. MD simulations have become increasingly useful in the modern drug development process. For example, in the lead discovery and lead optimization phases, MD facilitates the evaluation of the binding energetics and kinetics of the ligand-receptor interactions, therefore guiding the choice of the best candidate molecules for further development. in the future, the role of MD simulations in facilitating the drug development process is likely to grow substantially with the increasing computer power and advancements in the development of force fields and enhanced MD methodologies.
  • 3.9K
  • 20 Jan 2021
Topic Review
β-Glucan
β-glucans are complex polysaccharides that are found in several plants and foods, including mushrooms. β-glucans display an array of potentially therapeutic properties. 
  • 3.9K
  • 07 Feb 2021
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