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Topic Review
Brainstem Encephalitis
Brainstem encephalitis refers to inflammatory diseases affecting the midbrain, pons, and medulla oblongata. The causes of brainstem encephalitis include infections, autoimmune diseases, and paraneoplastic syndromes. Listeria is a common etiology of infectious rhombencephalitis. The trigeminal nerve has been proposed as a pathway through which Listeria monocytogenes reaches the brainstem after entering damaged oropharyngeal mucosa or periodontal tissues. Listeria monocytogenes may also invade the brainstem along the vagus nerve after it infects enteric neurons in the walls of the gastrointestinal tract.
  • 7.7K
  • 22 Oct 2020
Topic Review Video
Risk Management in Information Systems
Businesses are bombarded with great deals of risks, vulnerabilities, and unforeseen business interruptions in their lifetime, which negatively affect their productivity and sustainability within the market. Such risks require a risk management system to identify risks and risk factors and propose approaches to eliminate or reduce them. Risk management involves highly structured practices that should be implemented within an organization, including organizational planning documents. Continuity planning and fraud detection policy development are among the many critically important practices conducted through risk management that aim to mitigate risk factors, their vulnerability, and their impact. Information systems play a pivotal role in any organization by providing many benefits, such as reducing human errors and associated risks owing to the employment of sophisticated algorithms. Both the development and establishment of an information system within an organization contributes to mitigating business-related risks and also creates new types of risks associated with its establishment. Businesses must prepare for, react to, and recover from unprecedented threats that might emerge in the years or decades that follow.
  • 7.7K
  • 15 Dec 2021
Topic Review
Extraction of Peanut Skins
In addition to the edible kernel, the peanut seed consists of the woody outer shell and a paper-like substance that surrounds the kernel itself known as the testa or skin.
  • 7.7K
  • 28 Jan 2021
Topic Review
Sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) mineral particles or rock fragments. Most sandstone is composed of quartz or feldspar (both silicates) because they are the most resistant minerals to weathering processes at the Earth's surface, as seen in Bowen's reaction series. Like uncemented sand, sandstone may be any color due to impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Since sandstone beds often form highly visible cliffs and other topographic features, certain colors of sandstone have been strongly identified with certain regions. Rock formations that are primarily composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs. Fine-grained aquifers, such as sandstones, are better able to filter out pollutants from the surface than are rocks with cracks and crevices, such as limestone or other rocks fractured by seismic activity. Quartz-bearing sandstone can be converted into quartzite through metamorphism, usually related to tectonic compression within orogenic belts.
  • 7.7K
  • 15 Nov 2022
Topic Review
Wind Turbines
Wind turbines (WTs) are large devices utilized to convert the wind's kinetic energy into electricity. There are several different typologies of WTs, the most common type being the so-called Horizontal Axis Wind Turbine (HAWT) systems. In this configuration, the rotation axis of the rotor is parallel to the ground. Specific attention must be paid to the orientation with respect to the wind direction, which is different from other types of wind turbines such as those with a vertical axis (VAWT), whose orientation is independent of the prevailing wind direction. For HAWT, the three-bladed upwind configuration is the most common one, with the rotor facing the incoming wind. WTs can be deployed both on- or offshore and have very different blade lengths, which result in different sizes (especially regarding the tower height) and power output. Due to fatigue and exposure to outdoor elements, WT monitoring and diagnostics are strictly needed to reduce structural and mechanical failure and achieve cost-effective energy production. This requires both the Structural Health Monitoring of the WTs load-bearing components (tower, blades, foundations, etc) and the Condition Monitoring of their mechanical parts (gearbox, generator, etc).
  • 7.7K
  • 02 Mar 2022
Topic Review
Snake Dry Bites
Snake ‘dry bites’ are characterized by the absence of venom being injected into the victim during a snakebite incident. The dry bite mechanism and diagnosis are quite complex, and the lack of envenoming symptoms in these cases may be misinterpreted as a miraculous treatment or as proof that the bite from the perpetrating snake species is rather harmless.
  • 7.7K
  • 01 Dec 2020
Topic Review
Critical Factors in Renewable Energy Generation
The factors influencing the development of renewable energy in the electrical power sector can be grouped into four main clusters: (i) economic factors, (ii) legal and policy factors, (iii) social acceptance factors, and (iv) adverse impacts of renewable energy projects on the ecological environment.
  • 7.7K
  • 16 Dec 2021
Topic Review
Support Vector Machine
In machine learning, support-vector machines (SVMs, also support-vector networks) are supervised learning models with associated learning algorithms that analyze data used for classification and regression analysis. The Support Vector Machine (SVM) algorithm is a popular machine learning tool that offers solutions for both classification and regression problems. Developed at AT&T Bell Laboratories by Vapnik with colleagues (Boser et al., 1992, Guyon et al., 1993, Vapnik et al., 1997), it presents one of the most robust prediction methods, based on the statistical learning framework or VC theory proposed by Vapnik and Chervonekis (1974) and Vapnik (1982, 1995). Given a set of training examples, each marked as belonging to one or the other of two categories, an SVM training algorithm builds a model that assigns new examples to one category or the other, making it a non-probabilistic binary linear classifier (although methods such as Platt scaling exist to use SVM in a probabilistic classification setting). An SVM model is a representation of the examples as points in space, mapped so that the examples of the separate categories are divided by a clear gap that is as wide as possible. New examples are then mapped into that same space and predicted to belong to a category based on the side of the gap on which they fall. In addition to performing linear classification, SVMs can efficiently perform a non-linear classification using what is called the kernel trick, implicitly mapping their inputs into high-dimensional feature spaces. When data are unlabelled, supervised learning is not possible, and an unsupervised learning approach is required, which attempts to find natural clustering of the data to groups, and then map new data to these formed groups. The support-vector clustering algorithm, created by Hava Siegelmann and Vladimir Vapnik, applies the statistics of support vectors, developed in the support vector machines algorithm, to categorize unlabeled data, and is one of the most widely used clustering algorithms in industrial applications.
  • 7.7K
  • 14 Oct 2022
Topic Review
Quantum Vacuum Thruster
A quantum vacuum thruster (QVT or Q-thruster) is a theoretical system hypothesized to use the same principles and equations of motion that a conventional plasma thruster would use, namely magnetohydrodynamics (MHD), to make predictions about the behavior of the propellant. However, rather than using a conventional plasma as a propellant, a QVT would interact with quantum vacuum fluctuations of the zero-point field. The concept is controversial and generally not considered physically possible. However, if QVT systems were possible they could eliminate the need to carry propellant, being limited only by the availability of energy.
  • 7.7K
  • 11 Oct 2022
Topic Review Peer Reviewed
Mozambique: Country Profile
Mozambique is a Southern African tropical country; it forms a 4330 km coastline on the Indian Ocean side. It is one of the continent’s five former Portuguese colonies, with the economy relying mainly on agriculture and mining.
  • 7.6K
  • 03 Mar 2023
Topic Review
Grade Retention
Grade retention is a strategy for the remediation of learning or developmental delays. Students who cannot keep up with their peers or do not meet a predefined level repeat the same grade once again and by doing so have an extra year to get at the level that is needed to successfully manage the next grade. There are considerable doubts as regards the usefulness and effectiveness of retaining grades. Studies conclude that in the short term retaining grades may have a positive effect on academic achievement, but that this gain disappears in the longer term.
  • 7.6K
  • 30 Oct 2020
Topic Review
Synthetic Aperture Radar
SAR constellations 
  • 7.6K
  • 24 Aug 2020
Topic Review
Lost Lands
Lost lands can be continents, islands or other regions existing during prehistory, having since disappeared as a result of catastrophic geological phenomena or slowly rising sea levels since the end of the last Ice Age. Lost lands, where they existed, are supposed to have subsided into the sea, leaving behind only a few traces or legends. The term can also be extended to mythological lands generally, to underground civilizations, or even to whole planets. The classification of lost lands as continents, islands, or other regions is in some cases subjective; for example, Atlantis is variously described as either a "lost island" or a "lost continent". Lost land theories may originate in mythology or philosophy, or in scholarly or scientific theories, such as catastrophic theories of geology.
  • 7.6K
  • 11 Oct 2022
Topic Review
Integrated On-Board Charger-Traction Systems
The Integrated On-board Charger (iOBC) is the innovative technique to design the on-board charging system in which the motor coil and traction inverter is used during charging as grid filter and active front-end power factor correction unit respectively. This technique helps to increase charging power density, reduce vehicle size and weight.
  • 7.6K
  • 17 Aug 2022
Topic Review
Vegetable Oils as Lubricants
Vegetable oils have been used as metalworking fluids (MWFs) for many years, particularly in small-scale metalworking operations and in industries where environmental regulations are strict. Before the development of modern MWFs, vegetable oils were one of the most common lubricants used for metalworking tools. The use of vegetable oils can be traced back to ancient civilizations such as Egypt, Greece, and Rome, where olive oil was commonly used to lubricate metal tools and weapons. 
  • 7.6K
  • 19 Apr 2023
Topic Review
Dihedral (Aeronautics)
In aeronautics, dihedral is the angle between the left and right wings (or tail surfaces) of an aircraft. "Dihedral" is also used to describe the effect of sideslip on the rolling of the aircraft. Dihedral angle is the upward angle from horizontal of the wings or tailplane of a fixed-wing aircraft. "Anhedral angle" is the name given to negative dihedral angle, that is, when there is a downward angle from horizontal of the wings or tailplane of a fixed-wing aircraft. Dihedral angle has a strong influence on dihedral effect, which is named after it. Dihedral effect is the amount of roll moment produced in proportion to the amount of sideslip. Dihedral effect is a critical factor in the stability of an aircraft about the roll axis (the spiral mode). It is also pertinent to the nature of an aircraft's Dutch roll oscillation and to maneuverability about the roll axis. Longitudinal dihedral is a comparatively obscure term related to the pitch axis of an airplane. It is the angle between the zero-lift axis of the wing and the zero-lift axis of the horizontal tail. Longitudinal dihedral can influence the nature of controllability about the pitch axis and the nature of an aircraft's phugoid-mode oscillation. When the term "dihedral" (of an aircraft) is used by itself it is usually intended to mean "dihedral angle". However, context may otherwise indicate that "dihedral effect" is the intended meaning.
  • 7.6K
  • 27 Oct 2022
Biography
James Gosling
James Arthur Gosling, OC (born May 19, 1955) is a Canadian computer scientist, best known as the founder and lead designer behind the Java programming language.[1] James Gosling received a Bachelor of Science from the University of Calgary [2] and his M.A. and Ph.D. from Carnegie Mellon University, all in computer science.[3][4][5] He wrote a version of Emacs called Gosling Emacs (Gosmacs) wh
  • 7.6K
  • 24 Nov 2022
Topic Review
Solid Waste Management in Middle East Arab Countries
Solid waste production, specifically construction waste, in Middle Eastern Arab countries has dramatically increased. This is characterized by several factors, including rapid urbanization, common food wasting habits, diverse culture, lack of proper planning of solid waste processes, insufficient equipment, as well as lack of proper funding. The exponential growth in solid waste generation rates has led to hazards to health and the environment, causing issues related to air and water pollution under the already increasing pressure of climate change.
  • 7.6K
  • 17 Nov 2022
Topic Review
Theravada
Theravāda (/ˌtɛrəˈvɑːdə/; Pāli, lit. "School of the Elders") is the most commonly accepted name of Buddhism's oldest existing school. The school's adherents, termed Theravādins, have preserved their version of Gautama Buddha's teaching in the Pāli Canon. The Pāli Canon is the only complete Buddhist canon surviving in a classical Indian language, Pāli, which serves as the school's sacred language and lingua franca. For over a millennium, theravādins have endeavored to preserve the dhamma as recorded in their school's texts.[web 1] In contrast to Mahāyāna and Vajrayāna, Theravāda tends to be conservative in matters of doctrine and monastic discipline. Modern Theravāda derives from the Mahāvihāra sect, a Sri Lankan branch of the Vibhajjavādins, a sub-sect of the Indian Sthavira Nikaya, which began to establish itself on the island from the 3rd century BCE onwards. It was in Sri Lanka that the Pāli Canon was written down and the school's commentary literature developed. From Sri Lanka, the Theravāda Mahāvihāra tradition subsequently spread to the rest of Southeast Asia. It is the dominant religion in Cambodia, Laos, Myanmar, Sri Lanka, and Thailand and is practiced by minorities in India, Bangladesh, China, Nepal, and Vietnam. The diaspora of all of these groups, as well as converts around the world, also practice Theravāda. During the modern era, new developments have included Buddhist modernism, the Vipassana movement which reinvigorated Theravāda meditation practice [web 1] and the Thai Forest Tradition which reemphasized forest monasticism.
  • 7.6K
  • 05 Dec 2022
Topic Review
Hegemony
Hegemony (UK: /hɪˈɡɛməni, hɪˈdʒɛməni/, US: /hɪˈdʒɛməni/ (pronunciation (help·info)) or /ˈhɛdʒəˌmoʊni/) is the political, economic, or military predominance or control of one state over others. In Ancient Greece (8th century BC – 6th century AD), hegemony denoted the politico-military dominance of a city-state over other city-states. The dominant state is known as the hegemon. In the 19th century, hegemony came to denote the "Social or cultural predominance or ascendancy; predominance by one group within a society or milieu". Later, it could be used to mean "a group or regime which exerts undue influence within a society". Also, it could be used for the geopolitical and the cultural predominance of one country over others, from which was derived hegemonism, as in the idea that the Great Powers meant to establish European hegemony over Africa, Asia and Latin America. In cultural imperialism, the leader state dictates the internal politics and the societal character of the subordinate states that constitute the hegemonic sphere of influence, either by an internal, sponsored government or by an external, installed government. In international relations theory, hegemony denotes a situation of (i) great material asymmetry in favour of one state, that has (ii) enough military power to systematically defeat any potential contester in the system, (iii) controls the access to raw materials, natural resources, capital and markets, (iv) has competitive advantages in the production of value added goods, (v) generates an accepted ideology reflecting this status quo; and (vi) is functionally differentiated from other states in the system, being expected to provide certain public goods such as security, or commercial and financial stability. The Marxist theory of cultural hegemony, associated particularly with Antonio Gramsci, is the idea that the ruling class can manipulate the value system and mores of a society, so that their view becomes the world view (Weltanschauung): in Terry Eagleton's words, "Gramsci normally uses the word hegemony to mean the ways in which a governing power wins consent to its rule from those it subjugates". In contrast to authoritarian rule, cultural hegemony "is hegemonic only if those affected by it also consent to and struggle over its common sense".
  • 7.6K
  • 10 Nov 2022
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