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Topic Review Peer Reviewed

The Capital Asset Pricing Model

The capital asset pricing model (CAPM) is an influential paradigm in financial risk management. It formalizes mean-variance optimization of a risky portfolio given the presence of a risk-free investment such as short-term government bonds. The CAPM defines the price of financial assets according to the premium demanded by investors for bearing excess risk.

4.0K
13 Apr 2022

Topic Review

Inflammatory Pain Study in Animal-Models

Pain is an easily recognized sensation that is experienced by humans and animals alike. However, the process behind the production of the pain experience is a complex pathway that requires parallel integration of both the emotional and sensory experiences together with noxious perceptual information registered by multiple layers of our brain structure with the purpose of defending our body from harm’s way. Here, the complete protocol that is being adapted for inflammatory pain study in animals induced by different phlogogenic agents and different assessment methods were elaborated along with the underlying mechanism of actions. This provides a concise idea and improves our scientists’ understanding of inflammatory pain management in future research.

4.0K
05 Nov 2020

Topic Review

Ballast Contamination Mechanisms

Ballasted railway tracks constitute the major transportation grids in many countries across the globe; they convey commuters, as well as freight and bulk cargoes, between cities, mines, farmlands, and ports . The railtrack structure can be categorised into two groups: the substructure and the superstructure. The substructure comprises the subgrade, the sub-ballast, and the ballast, while the superstructure encompasses the sleepers (timber or concrete), the fastening mechanism, and the steel rails.

4.0K
14 Jan 2021

Topic Review

Baddeley's Model of Working Memory

Baddeley's model of working memory is a model of human memory proposed by Alan Baddeley and Graham Hitch in 1974, in an attempt to present a more accurate model of primary memory (often referred to as short-term memory). Working memory splits primary memory into multiple components, rather than considering it to be a single, unified construct. Baddeley & Hitch proposed their three-part working memory model as an alternative to the short-term store in Atkinson & Shiffrin's 'multi-store' memory model (1968). This model is later expanded upon by Baddeley and other co-workers to add a fourth component, and has become the dominant view in the field of working memory. However, alternative models are developing, providing a different perspective on the working memory system. The original model of Baddeley & Hitch was composed of three main components: the central executive which acts as a supervisory system and controls the flow of information from and to its slave systems: the phonological loop and the visuo-spatial sketchpad. The phonological loop stores verbal content, whereas the visuo-spatial sketchpad caters to visuo-spatial data. Both the slave systems only function as short-term storage centers. In 2000, Baddeley added a third slave system to his model, the episodic buffer. Baddeley & Hitch's argument for the distinction of two domain-specific slave systems in the older model was derived from experimental findings with dual-task paradigms. Performance of two simultaneous tasks requiring the use of two separate perceptual domains (i.e. a visual and a verbal task) is nearly as efficient as performance of the tasks individually. In contrast, when a person tries to carry out two tasks simultaneously that use the same perceptual domain, performance is less efficient than when performing the tasks individually. A fourth component of Baddeley's model was added 25 years later to complement the central executive system. The third slave system was designated as episodic buffer. It is considered a limited-capacity system that provides temporary storage of information by conjoining information from the subsidiary systems, and long-term memory, into a single episodic representation.

4.0K
04 Nov 2022

Topic Review

An ionocraft or ion-propelled aircraft (commonly known as a lifter or hexalifter) is a device that uses an electrical electrohydrodynamic (EHD) phenomenon to produce thrust in the air without requiring any combustion or moving parts. The term "ionocraft" dates back to the 1960s, an era in which EHD experiments were at their peak. In its basic form, it simply consists of two parallel conductive electrodes, one in the form of a fine wire and another which may be formed out of wire grid, tubes or foil skirts with a smooth round surface. When such an arrangement is powered by high voltage (in the range of a few kilovolts), it produces thrust. The ionocraft forms part of the EHD thruster family, but is a special case in which the ionisation and accelerating stages are combined into a single stage. The device is a popular science fair project for students. It is also popular among anti-gravity or so-called "electrogravitics" proponents, due to the research of Thomas Townsend Brown, who built these devices in the 1920s and incorrectly believed that he had found a way to modify gravity using electric fields. The term "lifter" is an accurate description because it is not an anti-gravity device; rather, it produces lift using the same basic principle as a rocket, i.e. from the equal but opposite force upward generated by the driving force downward, specifically by driving the ionized air downward in the case of the ionocraft. Much like a rocket or a jet engine (it can actually be much more thrust efficient than a jet engine), the force that an ionocraft generates is consistently oriented along its own axis, regardless of the surrounding gravitational field. Claims of the device also working in a vacuum have been disproved. Ionocraft require many safety precautions due to the high voltage required for their operation; nevertheless, a large subculture has grown up around this simple EHD thrusting device and its physics are now known to a much better extent.

4.0K
01 Dec 2022

Topic Review

OpenMP (Open Multi-Processing) is an application programming interface (API) that supports multi-platform shared-memory multiprocessing programming in C, C++, and Fortran, on many platforms, instruction-set architectures and operating systems, including Solaris, AIX, FreeBSD, HP-UX, Linux, macOS, and Windows. It consists of a set of compiler directives, library routines, and environment variables that influence run-time behavior. OpenMP is managed by the nonprofit technology consortium OpenMP Architecture Review Board (or OpenMP ARB), jointly defined by a broad swath of leading computer hardware and software vendors, including Arm, AMD, IBM, Intel, Cray, HP, Fujitsu, Nvidia, NEC, Red Hat, Texas Instruments, and Oracle Corporation. OpenMP uses a portable, scalable model that gives programmers a simple and flexible interface for developing parallel applications for platforms ranging from the standard desktop computer to the supercomputer. An application built with the hybrid model of parallel programming can run on a computer cluster using both OpenMP and Message Passing Interface (MPI), such that OpenMP is used for parallelism within a (multi-core) node while MPI is used for parallelism between nodes. There have also been efforts to run OpenMP on software distributed shared memory systems, to translate OpenMP into MPI and to extend OpenMP for non-shared memory systems.

4.0K
19 Oct 2022

Topic Review

In biology, tissue is a biological organizational level between cells and a complete organ. A tissue is an ensemble of similar cells and their extracellular matrix from the same origin that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues. The English word "tissue" derives from the French word "tissu", the past participle of the verb tisser, "to weave". The study of tissues is known as histology or, in connection with disease, as histopathology. Xavier Bichat is considered as the "Father of Histology". Plant histology is studied in both plant anatomy and physiology. The classical tools for studying tissues are the paraffin block in which tissue is embedded and then sectioned, the histological stain, and the optical microscope. Developments in electron microscopy, immunofluorescence, and the use of frozen tissue-sections have enhanced the detail that can be observed in tissues. With these tools, the classical appearances of tissues can be examined in health and disease, enabling considerable refinement of medical diagnosis and prognosis.

4.0K
26 Oct 2022

Topic Review

Capture Myopathy in Spotted Deer

Capture myopathy is a noninfectious disease of the muscle associated with capturing or handling of any animals.

4.0K
17 Jun 2021

Topic Review

The Aeroflot passenger fleet consists of narrow-body and wide-body aircraft from six aircraft families: the Airbus A320, the Airbus A330, the Airbus A350, the Boeing 737, the Boeing 777, and the Sukhoi Superjet 100. As of March 2020, there are 247 passenger aircraft registered in the Aeroflot fleet. For most of its history, Aeroflot's fleet consisted almost entirely of aircraft built by Soviet manufacturers such as Antonov, Ilyushin, and Tupolev. Following the Soviet Union's dissolution and subsequent partition of the airline, Aeroflot began replacing its old Soviet aircraft with modern Western and some new-generation Russian models. Aeroflot's CEO Vitaly Saveliev intends to make its fleet younger in accordance with its corporate strategy to keep the airline competitive with other international airlines.

4.0K
29 Nov 2022

Topic Review

The Impact of Regulatory Pressures on Governance

abstract: Purpose: With this paper, we aim to provide an insight on the regulatory reforms on corporate governance, brought about, by its ineffectiveness in the global financial crisis. Design/Approach/Methodology: To this effect we compared accounting ratios over a period of 10 years - 5 years prior and during financial crisis (i.e. 2006-2010) and 5-years post regulatory reforms on governance (i.e. 2014-2018) -using panel data of ratios for profitability, liquidity and efficiency. Findings: The general trend in the banks was that profitability and efficiency decreased drastically in the post regulatory period, contrary to liquidity, which increased, as higher capital buffers were imposed on banks. Practical Implications: This study is important because the burden of regulations is detrimental to the performance of public banks in the EU Mediterranean region. There are several arguments that the burden of compliance is becoming very costly and this is negatively affecting their profitability and efficiency. Originality/Value: These findings are of interest to economists and policymakers within the European Mediterranean region. Keywords: Governance, regulations on governance, changes in regulations, performance, financial crisis, governance and performance. JEL code: G21, G28.

4.0K
28 May 2020

Topic Review

Poliomyelitis, often called polio or infantile paralysis, is an infectious disease caused by the poliovirus. In about 0.5 percent of cases there is muscle weakness resulting in an inability to move. This can occur over a few hours to a few days. The weakness most often involves the legs but may less commonly involve the muscles of the head, neck and diaphragm. Many people fully recover. In those with muscle weakness about 2 to 5 percent of children and 15 to 30 percent of adults die. Another 25 percent of people have minor symptoms such as fever and a sore throat and up to 5 percent have headache, neck stiffness and pains in the arms and legs. These people are usually back to normal within one or two weeks. In up to 70 percent of infections there are no symptoms. Years after recovery post-polio syndrome may occur, with a slow development of muscle weakness similar to that which the person had during the initial infection. Poliovirus is usually spread from person to person through infected fecal matter entering the mouth. It may also be spread by food or water containing human feces and less commonly from infected saliva. Those who are infected may spread the disease for up to six weeks even if no symptoms are present. The disease may be diagnosed by finding the virus in the feces or detecting antibodies against it in the blood. The disease only occurs naturally in humans. The disease is preventable with the polio vaccine; however, multiple doses are required for it to be effective. The US Centers for Disease Control and Prevention recommends polio vaccination boosters for travelers and those who live in countries where the disease is occurring. Once infected there is no specific treatment. In 2016, there were 37 cases of wild polio and 5 cases of vaccine-derived polio. This is down from 350,000 wild cases in 1988. In 2014 the disease was only spreading between people in Afghanistan, Nigeria, and Pakistan . In 2015 Nigeria had stopped the spread of wild poliovirus but it reoccurred in 2016. Poliomyelitis has existed for thousands of years, with depictions of the disease in ancient art. The disease was first recognized as a distinct condition by the English physician Michael Underwood in 1789 and the virus that causes it was first identified in 1908 by the Austrian immunologist Karl Landsteiner. Major outbreaks started to occur in the late 19th century in Europe and the United States. In the 20th century it became one of the most worrying childhood diseases in these areas. The first polio vaccine was developed in the 1950s by Jonas Salk. It was hoped that vaccination efforts and early detection of cases would result in global eradication of the disease by 2018.

4.0K
10 Nov 2022

Topic Review

Plants as anti-inflammatory drugs

Plants represent the main source of molecules for the development of new drugs, which intensifies the interest of transnational industries in searching for substances obtained from plant sources, especially since the vast majority of species have not yet been studied chemically or biologically, particularly concerning anti-inflammatory action. Anti-inflammatory drugs can interfere in the pathophysiological process of inflammation, to minimize tissue damage and provide greater comfort to the patient. Therefore, it is important to note that due to the existence of a large number of species available for research, the successful development of new naturally occurring anti-inflammatory drugs depends mainly on a multidisciplinary effort to find new molecules. Although many review articles have been published in this regard, the majority presented the subject from a limited regional perspective.

4.0K
25 Aug 2020

Topic Review

Family Tree of the Malaysian Monarchs

The following is a family tree of the monarchs of Malaysia. - - - - The dashed line denotes a marriage ♀ - denotes a female.

4.0K
11 Nov 2022

Topic Review

Jewish Views on Evolution

Jewish views on evolution includes a continuum of views about the theory of evolution, experimental evolution, the origin of life, age of the universe, evolutionary creationism, and theistic evolution. Today, many Jews accept the theory of evolution and do not see it as incompatible with traditional Judaism, reflecting the emphasis of prominent rabbis such as the Vilna Gaon and Maimonides on the ethical rather than factual significance of scripture.

4.0K
10 Oct 2022

Biography

Sitaramdas Omkarnath

Sri Sri Sitaramdas Omkarnath (17 February 1892 – 6 December 1982) was a preeminent Indian Vaishnav Saint, 19th century Bhakti cult spiritual luminary and an unequaled humanitarian from the state of West Bengal, India. Addressed as Sri Sri Thakur Sitaramdas Omkarnath, where "Omkar" signifies the supreme cosmic enlightenment and attaining supreme consciousnes, he was heralded as the Divine Incar

4.0K
14 Nov 2022

Topic Review

Smart City Applications

Smart city applications are designed to take advantage of the smart city ICT and collected data to provide value-added smart features. These applications use data analytics, intelligent techniques and other advanced technologies to make smart decisions that improve the smart city's operations and quality of life.

4.0K
17 Dec 2021

Topic Review

Defect-Related Etch Pits on Crystals and Their Utilization

Etch pits could form on an exposed surface of a crystal when the crystal is exposed to an etching environment or chemicals. Due to different dissolution rates along various crystalline directions in a crystal, the dissolution process is anisotropic; hence, etch pits usually have a regular shape. The morphology, size, and density of etch pits can be affected by various factors, including the chemical composition of the etchant, etching time, etching temperature, status of the matrix, and so on. Traditionally, etch pits are utilized to evaluate the dislocation density and some defect-related properties. Now, in the modern fabrication industries, the relationship between etch pits and defects has been utilized more skillfully. High-quality crystals can be fabricated by controlling dislocations revealed by etch pits. Meanwhile, with the as-revealed dislocation as the diffusion path of atoms, new crystals will emerge in corresponding etch pits.

4.0K
11 Nov 2022

Topic Review

The 214 Kangxi radicals (Chinese: 康熙部首; pinyin: Kāngxī bùshǒu), also known as the Zihui radicals, form a system of radicals (部首) of Chinese characters. The radicals are numbered in stroke count order. They are the most popular system of radicals for dictionaries that order Traditional Chinese characters (hanzi, hanja, kanji, chữ hán) by radical and stroke count. They are officially part of the Unicode encoding system for CJKV characters, in their standard order, under the coding block "Kangxi radicals", while their graphic variants are contained in the "CJK Radicals Supplement". Thus, a reference to "radical 61", for example, without additional context, refers to the 61st radical of the Kangxi Dictionary, 心; xīn "heart". Originally introduced in the 1615 Zihui (字彙), they are more commonly named in relation to the Kangxi Dictionary of 1716 (Kāngxī 康熙 being the era name for 1662–1723). The 1915 encyclopedic word dictionary Ciyuan (辭源) also uses this system. In modern times, many dictionaries that list Traditional Chinese head characters continue to use this system. For example, the Wang Li Character Dictionary of Ancient Chinese (王力古漢語字典, 2000) adopted the Kangxi radicals system. The system of 214 Kangxi radicals is based on the older system of 540 radicals used in the Han-era Shuowen Jiezi. Since 2009, the PRC government has promoted a 201-radical system (Table of Han Character Radicals, 汉字部首表) as a national standard for Simplified Chinese (see list of Xinhua Zidian radicals).

4.0K
22 Nov 2022

Topic Review

Bioactive Glass

Bioactive glass (BAG) consist of known biocompatible and bioactive minerals, including fluorapatite (FAP), wollastonite, diopside, and tricalcium phosphate. A bioactive material can interact with the biological environment to elicit a specific biological response and they can be osteoconductive or osteoinductive. Bioactive Glasses are amorphous solids with the irregular organization of atoms, optically transparent, and brittle consisting of silica networks. They possesses bioactivity and antimicrobial properties as presented n following sections. The bioactivity of BAGs involves several steps; BAGs immediately undergo ionic dissolution and glass degradation via the exchange of H+ ions in the solution and Na+ and Ca2+ from the glass network. BAG exhibits antimicrobial properties against various pathogens, e.g pathogens associated with sinusitis and osteomyelitis.

4.0K
22 Oct 2020

Topic Review

Empathizing–Systemizing Theory

The empathizing–systemizing (E–S) theory is a theory on the psychological basis of autism and male–female neurological differences originally put forward by English clinical psychologist Simon Baron-Cohen. It classifies individuals based on abilities in empathic thinking (E) and systematic thinking (S). It measures skills using an Empathy Quotient (EQ) and Systemizing Quotient (SQ) and attempts to explain the social and communication symptoms in autism spectrum disorders as deficits and delays in empathy combined with intact or superior systemizing. According to Baron-Cohen, the E–S theory has been tested using the Empathy Quotient (EQ) and Systemizing Quotient (SQ), developed by him and colleagues, and generates five different 'brain types' depending on the presence or absence of discrepancies between their scores on E or S. E–S profiles show that the profile E>S is more common in females than in males, and the profile S>E is more common in males than in females. Baron-Cohen and associates say the E–S theory is a better predictor than gender of who chooses STEM subjects (Science, Technology, Engineering and Mathematics). The E–S theory has been extended into the extreme male brain (EMB) theory of autism and Asperger syndrome, which are associated in the E–S theory with below-average empathy and average or above-average systemizing. Baron-Cohen's studies and theory have faced some criticism.

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18 Oct 2022

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