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Topic Review
Magnitude
In astronomy, magnitude is a unitless measure of the brightness of an object in a defined passband, often in the visible or infrared spectrum, but sometimes across all wavelengths. An imprecise but systematic determination of the magnitude of objects was introduced in ancient times by Hipparchus. The scale is logarithmic and defined such that a magnitude 1 star is exactly 100 times brighter than a magnitude 6 star. Thus each step of one magnitude is [math]\displaystyle{ \sqrt{100} \approx 2.512 }[/math] times brighter than the next faintest. The brighter an object appears, the lower the value of its magnitude, with the brightest objects reaching negative values. Astronomers use two different definitions of magnitude: apparent magnitude and absolute magnitude. The apparent magnitude (m) is the brightness of an object as it appears in the night sky from Earth. Apparent magnitude depends on an object's intrinsic luminosity, its distance, and the extinction reducing its brightness. The absolute magnitude (M) describes the intrinsic luminosity emitted by an object and is defined to be equal to the apparent magnitude that the object would have if it were placed at a certain distance from Earth, 10 parsecs for stars. A more complex definition of absolute magnitude is used for planets and small Solar System bodies, based on its brightness at one astronomical unit from the observer and the Sun. The Sun has an apparent magnitude of −27 and Sirius, the brightest visible star in the night sky, −1.46. Venus at its brightest is -5. The International Space Station (ISS) sometimes reaches a magnitude of −6.
  • 3.6K
  • 28 Sep 2022
Topic Review
Mitogen-Activated Protein Kinase Signaling Pathway
The basic composition of the mitogen-activated protein kinase (MAPK) pathway is divided into three modules in sequence, with a cascade effect: MAPK kinase kinase (MAPKKK), MAPK kinase (MAPKK), and MAPK. The MAPK signaling pathway is activated in over 50% of human oral cancer cases.
  • 3.6K
  • 11 Oct 2022
Topic Review
List of Ant Genera
Ants (family Formicidae in the order Hymenoptera) are the most species-rich of all social insects, with more than 12,000 described species and many others awaiting description. Formicidae is divided into 21 subfamilies, of which 17 are extant and four subfamilies are extinct, described from fossils. In total more than 300 genera have been described. Ants have come to occupy virtually all major terrestrial habitats, with the exception of tundra and cold ever-wet forests. They display a wide range of social behaviors, foraging habits and associations with other organisms, which has generated scientific and public interest. The following is a list of worldwide ant genera organised by subfamily.
  • 3.6K
  • 09 Nov 2022
Topic Review
Maple
Maple is a symbolic and numeric computing environment as well as a multi-paradigm programming language. It covers several areas of technical computing, such as symbolic mathematics, numerical analysis, data processing, visualization, and others. A toolbox, MapleSim, adds functionality for multidomain physical modeling and code generation. Maple's capacity for symbolic computing include those of a general-purpose computer algebra system. For instance, it can manipulate mathematical expressions and find symbolic solutions to certain problems, such as those arising from ordinary and partial differential equations. Maple is developed commercially by the Canadian software company Maplesoft. The name 'Maple' is a reference to the software's Canadian heritage.
  • 3.6K
  • 27 Jul 2026
Topic Review
Haskell (Programming Language)
Haskell (/ˈhæskəl/) is a general-purpose, statically-typed, purely functional programming language with type inference and lazy evaluation. Designed for teaching, research and industrial application, Haskell has pioneered a number of programming language features such as type classes, which enable type-safe operator overloading. Haskell's main implementation is the Glasgow Haskell Compiler (GHC). It is named after logician Haskell Curry. Haskell's semantics are historically based on those of the Miranda programming language, which served to focus the efforts of the initial Haskell working group. The last formal specification of the language was made in July 2010, while the development of GHC has expanded Haskell via language extensions. The next formal specification (As of 2020). On 29 October 2021 GHC2021 was released in GHC version 9.2.1. Haskell is used in academia and industry. (As of May 2021), Haskell was the 28th most popular programming language by Google searches for tutorials, and made up less than 1% of active users on the GitHub source code repository.
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  • 05 Dec 2022
Topic Review
Biogas as Energy in Rural Sector and Significance
In rural areas, where access to conventional energy sources is limited, alternative energy options such as biogas production offer tremendous potential. The sustainable utilization of biowaste resources for biogas production is a promising solution for meeting rural bioenergy requirements. Biowaste, such as agricultural residues, food waste, and animal manure, represents a significant source of organic material that can be converted into biogas through anaerobic digestion.
  • 3.6K
  • 27 Jul 2023
Topic Review
Tricarboxylic Acid (TCA) Cycle Intermediates
The tricarboxylic acid cycle (TCA) is a series of chemical reactions used in aerobic organisms to generate energy via the oxidation of acetylcoenzyme A (CoA) derived from carbohydrates, fatty acids and proteins. 
  • 3.6K
  • 20 Feb 2021
Topic Review
Neurobiological Mechanisms of Dreaming
Dream research has advanced significantly over the last twenty years, thanks to the new applications of neuroimaging and electrophysiological techniques. Many findings pointed out that mental activity during sleep and wakefulness shared similar neural bases. On the other side, recent studies have highlighted that dream experience is promoted by significant brain activation, characterized by reduced low frequencies and increased rapid frequencies. Additionally, several studies confirmed that the posterior parietal area and prefrontal cortex are responsible for dream experience. Further, early results revealed that dreaming might be manipulated by sensory stimulations that would provoke the incorporation of specific cues into the dream scenario. Recently, transcranial stimulation techniques have been applied to modulate the level of consciousness during sleep, supporting previous findings and adding new information about neural correlates of dream recall. Overall, although multiple studies suggest that both the continuity and activation hypotheses provide a growing understanding of neural processes underlying dreaming, several issues are still unsolved. The impact of state-/trait-like variables, the influence of circadian and homeostatic factors, and the examination of parasomnia-like events to access dream contents are all opened issues deserving further deepening in future research.
  • 3.6K
  • 01 Mar 2021
Topic Review
Photocatalytic Reactors Design
The photoreactors design and concepts vary based on the working regime (static or dynamic), photocatalyst morphology (powders or bulk) and volume.
  • 3.6K
  • 10 May 2021
Topic Review
ZIS-5 (Truck)
The ZIS-5 (Russian: ЗиС-5) was a 4x2 Soviet truck produced by Moscow ZIS factory from 1932 to 1948 (first one made at the end of 1930).
  • 3.6K
  • 04 Nov 2022
Topic Review
Ecology and Evolution of Saccharomyces cerevisiae
The yeast distributes ubiquitously in nature with clearly structured populations. The baker’s yeast Saccharomyces cerevisiae has become a powerful model in ecology and evolutionary biology. The global genetic diversity of S. cerevisiae is mainly contributed by strains from Far East Asia, and the ancient basal lineages of the species have been found only in China, supporting an ‘out-of-China’ origin hypothesis. The wild and domesticated populations are clearly separated in phylogeny and exhibit hallmark differences in sexuality, heterozygosity, gene copy number variation (CNV), horizontal gene transfer (HGT) and introgression events, and maltose utilization ability. The domesticated strains from different niches generally form distinct lineages and harbor lineage-specific CNVs, HGTs and introgressions, which contribute to their adaptations to specific fermentation environments. 
  • 3.6K
  • 01 Mar 2022
Topic Review
Entoptic Phenomenon
Entoptic phenomena (from grc ἐντός (entós) 'within', and ὀπτικός (optikós) 'visual') are visual effects whose source is within the human eye itself. (Occasionally, these are called entopic phenomena, which is probably a typographical mistake.) In Helmholtz's words: "Under suitable conditions light falling on the eye may render visible certain objects within the eye itself. These perceptions are called entoptical."
  • 3.6K
  • 02 Nov 2022
Topic Review
ECG Monitoring Systems
Health monitoring and its related technologies is an attractive research area. The electrocardiogram (ECG) has always been a popular measurement scheme to assess and diagnose cardiovascular diseases (CVDs). The number of ECG monitoring systems in the literature is expanding exponentially. Hence, it is very hard for researchers and healthcare experts to choose, compare, and evaluate systems that serve their needs and fulfill the monitoring requirements. This accentuates the need for a verified reference guiding the design, classification, and analysis of ECG monitoring systems, serving both researchers and professionals in the field. In this paper, we propose a comprehensive, expert-verified taxonomy of ECG monitoring systems and conduct an extensive, systematic review of the literature. This provides evidence-based support for critically understanding ECG monitoring systems’ components, contexts, features, and challenges. Hence, a generic architectural model for ECG monitoring systems is proposed, an extensive analysis of ECG monitoring systems’ value chain is conducted, and a thorough review of the relevant literature, classified against the experts’ taxonomy, is presented, highlighting challenges and current trends. Finally, we identify key challenges and emphasize the importance of smart monitoring systems that leverage new technologies, including deep learning, artificial intelligence (AI), Big Data and Internet of Things (IoT), to provide efficient, cost-aware, and fully connected monitoring systems.
  • 3.6K
  • 29 Oct 2020
Topic Review
Cold Plasma
Plasma is referred to as the fourth state of matter. It is an ionized gas comprising several excited atomic, molecular, ionic, and radical species, co-existing with electrons, positive and negative ions, free radicals, gas atoms, molecules in the ground or excited state, and quanta of electromagnetic radiation (UV photons and visible light).
  • 3.6K
  • 03 Dec 2021
Topic Review
Hydrogen-Based Hybrid Microgrid System
Hydrogen is acknowledged as a potential and appealing energy carrier for decarbonizing the sectors that contribute to global warming, such as power generation, industries, and transportation. Many people are interested in employing low-carbon sources of energy to produce hydrogen by using water electrolysis. Additionally, the intermittency of renewable energy supplies, such as wind and solar, makes electricity generation less predictable, potentially leading to power network incompatibilities. Hence, hydrogen generation and storage can offer a solution by enhancing system flexibility. Hydrogen saved as compressed gas could be turned back into energy or utilized as a feedstock for manufacturing, building heating, and automobile fuel.
  • 3.6K
  • 10 Nov 2022
Topic Review
Electrochemical Immunosensor
Electrochemical immunosensors (EI) are systems that combine the analytical power of electrochemical techniques and the high selectivity and specificity of antibodies in a solid phase immunoassay for a target analyte.
  • 3.6K
  • 02 Dec 2021
Topic Review
Role of NF-kB in Alzheimer’s Disease
Alzheimer’s Disease (AD) is the most common neurodegenerative disease worldwide, with a high prevalence that is expected to double every 20 years. Besides the formation of Aβ plaques and neurofibrillary tangles, neuroinflammation is one the major phenotypes that worsens AD progression. Indeed, the nuclear factor-κB (NF-κB) is a well-established inflammatory transcription factor that fuels neurodegeneration.
  • 3.6K
  • 23 Aug 2022
Topic Review
Malacostraca
Malacostraca (from New Latin; from grc μαλακός (malakós) 'soft', and όστρακον "shell") is the largest of the six classes of crustaceans, containing about 40,000 living species, divided among 16 orders. Its members, the malacostracans, display a great diversity of body forms and include crabs, lobsters, crayfish, shrimp, krill, prawns, woodlice, amphipods, mantis shrimp and many other, less familiar animals. They are abundant in all marine environments and have colonised freshwater and terrestrial habitats. They are segmented animals, united by a common body plan comprising 20 body segments (rarely 21), and divided into a head, thorax, and abdomen.
  • 3.6K
  • 31 Oct 2022
Topic Review
Erysipelas
Erysipelas (/ˌɛrəˈsɪpələs/) is a relatively common bacterial infection of the superficial layer of the skin (upper dermis), extending to the superficial lymphatic vessels within the skin, characterized by a raised, well-defined, tender, bright red rash, typically on the face or legs, but which can occur anywhere on the skin. It is a form of cellulitis and is potentially serious. Erysipelas is usually caused by the bacteria Streptococcus pyogenes, also known as group A β-hemolytic streptococci, through a break in the skin such as from scratches or an insect bite. It is more superficial than cellulitis, and is typically more raised and demarcated. The term is from Greek ἐρυσίπελας (erysípelas), meaning "red skin". In animals, erysipelas is a disease caused by infection with the bacterium Erysipelothrix rhusiopathiae. The disease caused in animals is called Diamond Skin Disease, which occurs especially in pigs. Heart valves and skin are affected. Erysipelothrix rhusiopathiae can also infect humans, but in that case, the infection is known as erysipeloid.
  • 3.6K
  • 23 Nov 2022
Biography
P. M. H. Atwater
P. M. H. Atwater (born Phyllis Marie DeKeyser, September 19, 1937) is a North American writer and researcher on subjects related to Idaho, life and death issues, and spirituality from a New Thought point of view. Atwater was born in Twin Falls, Idaho[1] and was later adopted by Kenneth L. Johnston. She married John Bernard Huffman in 1956 (divorced in 1976) and had three children: Kelly, Nata
  • 3.6K
  • 12 Dec 2022
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