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Topic Review
Metal Matrix Composite
Composites are generally categorized into three main categories based on the matrix substance. They are called metal matrix composite (MMC), polymer matrix composite (PMC), and ceramic matrix composite (CMC), respectively. MMC gives more elevated ductile properties than CMCs and better environmental stability than PMCs. Additionally, MMCs offer good thermal conductivity (from 220 to 580 W·m−1·K−1), wear resistance (0.01025), wear rate (g·m−1), erosion, and shear strength.
  • 3.0K
  • 06 Sep 2021
Topic Review
Blue Gene
Blue Gene is an IBM project aimed at designing supercomputers that can reach operating speeds in the PFLOPS (petaFLOPS) range, with low power consumption. The project created three generations of supercomputers, Blue Gene/L, Blue Gene/P, and Blue Gene/Q. Blue Gene systems have often led the TOP500 and Green500 rankings of the most powerful and most power efficient supercomputers, respectively. Blue Gene systems have also consistently scored top positions in the Graph500 list. The project was awarded the 2009 National Medal of Technology and Innovation. As of 2015, IBM seems to have ended the development of the Blue Gene family though no public announcement has been made. IBM's continuing efforts of the supercomputer scene seems to be concentrated around OpenPower, using accelerators such as FPGAs and GPUs to battle the end of Moore's law.
  • 3.0K
  • 29 Sep 2022
Topic Review
Chronic Low-Grade Inflammation
Chronic Low-Grade Inflammation (CLGI) can be formally defined as a pathological state lacking overt inflammation, but characterized by continuous and unresolved activation of inflammation mediators. It results in increased production of cytokines, reactive oxygen species, macrophage infiltration, adipocyte imbalance, or vascular damage; these effects are associated with metabolically active tissues such as adipose tissue, skeletal muscle, and the liver, implicating CLGI in metabolic diseases. Age-related immunosenescence and the accumulation of cellular debris are also part of CLGI evolution in older people.
  • 3.0K
  • 13 Dec 2021
Topic Review
Balloon (Aeronautics)
In aeronautics, a balloon is an unpowered aerostat, which remains aloft or floats due to its buoyancy. A balloon may be free, moving with the wind, or tethered to a fixed point. It is distinct from an airship, which is a powered aerostat that can propel itself through the air in a controlled manner. Many balloons have a basket, gondola, or capsule suspended beneath the main envelope for carrying people or equipment (including cameras and telescopes, and flight-control mechanisms).
  • 3.0K
  • 27 Oct 2022
Topic Review
Chromothripsis
Chromothripsis has been defined as complex patterns of alternating genes copy number changes (normal, gain or loss) along the length of a chromosome or chromosome segment (International System for Human Cytogenomic Nomenclature 2020). The phenomenon of chromothripsis was discovered in 2011 and changed the concept of genome variability, mechanisms of oncogenic transformation, and hereditary diseases.
  • 3.0K
  • 27 May 2021
Topic Review
16:9
16:9 (1.77:1) (16:9 = 42:32) is an aspect ratio with a width of 16 units and height of 9. Since 2010 it has become the most common aspect ratio for televisions and computer monitors, and is also the international standard format of HDTV, Full HD, non-HD digital television and analog widescreen television. This has replaced the old 4:3 aspect ratio.
  • 3.0K
  • 27 Oct 2022
Topic Review
Green Taxes in Africa
Environmental or green taxation has been increasingly seen as a productive economic instrument to generate incentives to stimulate more environmentally friendly consumption and production choices and trends. Growing attention to environmental challenges such as the lack of optimum, effective, and responsible usage of natural resources, health concerns from the use of some energy resources, environmental degradation, and climate change have driven the implementation of green taxes. These taxes have been used by various countries, regions and continents on variegated areas and driven by an array of motives. The African continent has also put in place environmental taxes as evidenced in various countries.
  • 3.0K
  • 28 Sep 2022
Topic Review
Bacterial Biofilm Formation and Pathogenesis
Biofilm formation is an integral part of the microbial life cycle in nature. In food processing environments, bacterial transmissions occur primarily through raw or undercooked foods and by cross-contamination during unsanitary food preparation practices. Foodborne pathogens form biofilms as a survival strategy in various unfavorable environments, which also become a frequent source of recurrent contamination and outbreaks of foodborne illness.
  • 3.0K
  • 23 Sep 2021
Topic Review
Silanes
Silanes, as organic-inorganic hybrid modifiers of hyperbranched polymer (HBP), are of great interest as they resulted in a tremendous improvement in HBP properties like increasing thermal, mechanical and electrical properties compared to that of organic-only moieties. The basic components of silanes are monomeric silicon (Si) compounds with four substituent groups attached to the Si atom, which can be of any combination of reactive or non-reactive inorganic or organic groups, which are the fundamental building blocks of silanes.
  • 3.0K
  • 14 Jun 2023
Topic Review
Learning Disability
Learning disability, learning disorder, or learning difficulty (British English) is a condition in the brain that causes difficulties comprehending or processing information and can be caused by several different factors. Given the "difficulty learning in a typical manner", this does not exclude the ability to learn in a different manner. Therefore, some people can be more accurately described as having a "learning difference", thus avoiding any misconception of being disabled with a lack of ability to learn and possible negative stereotyping. In the United Kingdom, the term "learning disability" generally refers to an intellectual disability, while difficulties such as dyslexia and dyspraxia are usually referred to as "learning difficulties". While learning disability and learning disorder are often used interchangeably, they differ in many ways. Disorder refers to significant learning problems in an academic area. These problems, however, are not enough to warrant an official diagnosis. Learning disability, on the other hand, is an official clinical diagnosis, whereby the individual meets certain criteria, as determined by a professional (such as a psychologist, psychiatrist, speech language pathologist, or pediatrician). The difference is in degree, frequency, and intensity of reported symptoms and problems, and thus the two should not be confused. When the term "learning disorder" is used, it describes a group of disorders characterized by inadequate development of specific academic, language, and speech skills. Types of learning disorders include reading (dyslexia), arithmetic (dyscalculia) and writing (dysgraphia). The unknown factor is the disorder that affects the brain's ability to receive and process information. This disorder can make it problematic for a person to learn as quickly or in the same way as someone who is not affected by a learning disability. People with a learning disability have trouble performing specific types of skills or completing tasks if left to figure things out by themselves or if taught in conventional ways. Individuals with learning disabilities can face unique challenges that are often pervasive throughout the lifespan. Depending on the type and severity of the disability, interventions, and current technologies may be used to help the individual learn strategies that will foster future success. Some interventions can be quite simplistic, while others are intricate and complex. Current technologies may require student training to be effective classroom supports. Teachers, parents, and schools can create plans together that tailor intervention and accommodations to aid the individuals in successfully becoming independent learners. A multi-disciplinary team frequently helps to design the intervention and to coordinate the execution of the intervention with teachers and parents. This team frequently includes school psychologists, special educators, speech therapists (pathologists), occupational therapists, psychologists, ESL teachers, literacy coaches, and/or reading specialists.
  • 3.0K
  • 10 Nov 2022
Topic Review
Long-Term Memory
Long-term memory (LTM) is the stage of the Atkinson–Shiffrin memory model in which informative knowledge is held indefinitely. It is defined in contrast to short-term and working memory, which persist for only about 18 to 30 seconds. Long-term memory is commonly labelled as explicit memory (declarative), as well as episodic memory, semantic memory, autobiographical memory, and implicit memory (procedural memory).
  • 3.0K
  • 24 Nov 2022
Topic Review
Grand Power K100
The K100 is a 9×19mm semi-automatic pistol designed and built by Grand Power s.r.o. in Slovenská Ľupča, Slovakia located approximately 11 kilometers east of Banská Bystrica, Slovakia which is the region's major city.
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  • 03 Nov 2022
Topic Review
2017 Catalan Independence Referendum
The Catalan independence referendum of 2017, also known by the numeronym 1-O (for "1 October") in Spanish media, was an independence referendum held on 1 October 2017 in the Spanish autonomous community of Catalonia, passed by the Parliament of Catalonia as the Law on the Referendum on Self-determination of Catalonia and called by the Generalitat de Catalunya. It was declared unconstitutional on 7 September 2017 and suspended by the Constitutional Court of Spain after a request from the Spanish government, who declared it a breach of the Spanish Constitution. Additionally, in early September the High Court of Justice of Catalonia had issued orders to the police to try to prevent it, including the detention of various persons responsible for its preparation. Due to alleged irregularities during the voting process as well as to the use of force by the National Police Corps and Civil Guard, international observers invited by the Generalitat declared that the referendum failed to meet the minimum international standards for elections. The referendum was approved by the Catalan parliament in a session in which only nationalist parliamentarians participated on 6 September 2017 along with the Law of juridical transition and foundation of the Republic of Catalonia the following day 7 September, which stated that independence would be binding with a simple majority, without requiring a minimum turnout. After being suspended, the law was finally declared void on 17 October, being also unconstitutional according to the Statute of Autonomy of Catalonia which requires a two-thirds majority, 90 seats, in the Catalan parliament for any change to Catalonia's status. The referendum question, which voters answered with "Yes" or "No", was "Do you want Catalonia to become an independent state in the form of a republic?". The "Yes" side won, with 2,044,038 (92.01%) voting for independence and 177,547 (7.99%) voting against, on a turnout of 43.03%. The Catalan government estimated that up to 770,000 votes were not cast due to polling stations being closed off during the police crackdown, although the "universal census" system introduced earlier in the day allowed electors to vote at any given polling station. Catalan government officials have argued that the turnout would have been higher were it not for Spanish and Catalan police suppression of the vote. On the other hand, most voters who did not support Catalan independence did not turn out, as the constitutional political parties asked citizens not to participate in what they considered an illegal referendum. Additionally, numerous cases of voters casting their votes several times or with lack of identification were reported, and the counting process and the revision of the census were not performed with quality standards ensuring impartiality. In the days leading to the referendum, the High Court of Justice of Catalonia ordered police forces to impede the use of public premises for the imminent voting. However, on the day of the referendum, the inaction of part of the autonomous police force of Catalonia, the Mossos d'Esquadra, allowed many polling stations to open. The National Police Corps and the Guardia Civil intervened and raided several polling stations after they opened. 893 civilians and 111 agents of the National Police and the Guardia Civil were reported to have been injured. According to various sources these previously reported figures may have been exaggerated. According to the judge from Barcelona who is currently investigating the accusations of police violence, there were 218 persons injured on that day in the city of Barcelona alone, 20 of whom were agents. According to the official final report by the Catalan Health Service (CatSalut) of the Generalitat 1066 civilians, 11 agents of the National Police and the Guardia Civil and 1 agent of the regional police, the Mossos d'Esquadra, were injured. The United Nations High Commissioner for Human Rights, Zeid Ra'ad Al Hussein, urged the Spanish government to prove all acts of violence that took place to prevent the referendum. The police action also received criticism from Amnesty International and Human Rights Watch which defined it as an "excessive and unnecessary use of force". Spanish Supreme Court judge Pablo Llarena stated Puigdemont ignored the repeated warnings he received about the escalation of violence if the referendum was held. Mossos d'Esquadra are being investigated for disobedience, for allegedly not having complied with the orders of the High Court of Justice of Catalonia. Including Josep Lluís Trapero Álvarez, the Mossos d'Esquadra major, who is being investigated for sedition by the Spanish National Court. Mossos d'Esquadra deny those accusations and allege they obeyed the orders but applied the principle of proportionality, which is required by Spanish law in all police operations.
  • 3.0K
  • 07 Nov 2022
Topic Review
Heat Recovery from Wastewater
Wastewater from domestic, industrial and commercial developments maintains considerable amounts of thermal energy after discharging into the sewer system. 
  • 3.0K
  • 29 Jun 2021
Topic Review
Hobbes's Moral and Political Philosophy
Thomas Hobbes’s moral and political philosophy is constructed around the basic premise of social and political order, explaining how humans should live in peace under a sovereign power so as to avoid conflict within the ‘state of nature’. Hobbes’s moral philosophy and political philosophy are significantly intertwined; his moral thought is based around ideas of human nature, which determine the interactions that make up his political philosophy.  Hobbes’s moral philosophy therefore provides justification for, and informs, the theories of sovereignty and the state of nature that underpin his political philosophy. In utilising methods of deductive reasoning and motion science, Hobbes examines human emotion, reason and knowledge to construct his ideas of human nature (moral philosophy). This methodology critically influences his politics, determining the interactions of conflict (in the state of nature) which necessitate the creation of a politically authoritative State to ensure the maintenance of peace and cooperation. This method is used and developed in works such as The Elements of Law (1640), De Cive (1642), Leviathan (1651) and Behemoth (1681).
  • 3.0K
  • 30 Sep 2022
Topic Review
Additively Manufactured Aluminium Alloys
Metal additive manufacturing (MAM), also known as metal 3D printing, is a rapidly growing industry based on the fabrication of complex metal parts with improved functionalities. During MAM, metal parts are produced in a layer by layer fashion using 3D computer–aided design models. The advantages of using this technology includes the reduction of materials waste, high efficiency for small production runs, near net shape manufacturing, ease of change or revision of versions of a product, support of lattice structures, and rapid prototyping. Numerous metals and alloys can nowadays be processed by additive manufacturing techniques. Among them, Al-based alloys are of great interest for the automotive and aeronautic industry due to their relatively high strength and stiffness to weight ratio, good wear and corrosion resistance, and recycling potential. The special conditions associated with the MAM processes are known to produce in these materials a very fine microstructure with unique directional growth features far from equilibrium. This distinctive microstructure, together with other special features and microstructural defects originating from the additive manufacturing process are known to greatly influence the corrosion behavior of these materials. Several works have already been conducted in this direction. However, a number of issues concerning the corrosion and corrosion protection of these materials are still not well understood. This work reviews the main studies to date investigating the corrosion aspects of additively manufactured aluminium alloys. It also provides a summary and outlook of relevant directions to be explored in future research.
  • 3.0K
  • 13 Jan 2021
Topic Review
The 4 Helix Model and Tourism Social Entrepreneurships
The COVID-19 crisis has promoted innovation, support, and incentives among the four helixes, in which the STEs have benefited. As conclusions, the four helix model is functional to face the adversities of COVID-19 as long as there is planning within the entrepreneurships and the link with said model helix participants.
  • 3.0K
  • 10 Jan 2022
Topic Review
Emerging Thermo-Mechanical Energy Storage Technologies
Thermo-mechanical energy storage can be a cost-effective solution to provide flexibility and balance highly renewable energy systems. Thermo-Mechanical Energy Storage (TMES) can be directly compared with pumped hydro storage because they have similar discharge characteristics and capacity (order of 100 s of MW).
  • 3.0K
  • 13 Sep 2022
Topic Review
Virtual Reality and Metacognition for Learning Disabilities
Learning disabilities are defined as a set of neurodevelopmental disorders of biological basis that induce cognitive abnormalities as well as symptoms related to emotional and behavioral disorders. Metacognition is defined by Drigas and Mitsea as the “set of regulatory meta-abilities and meta-skills that are consciously applied aiming at the smooth operation of the cognitive & psychophysiological mechanism as a means of achieving functional capability, self-efficacy, independent living & life satisfaction. Virtual reality (VR) is commonly regarded as a technology that induces virtual immersion in a digital world via the use of a computerized graphic simulation that allows users to immerse themselves in an interactive three-dimensional world brimming with various sensory and emotional experiences.
  • 3.0K
  • 21 Oct 2022
Topic Review
Dispersion
A dispersion is a system in which distributed particles of one material are dispersed in a continuous phase of another material. The two phases may be in the same or different states of matter. Dispersions are classified in a number of different ways, including how large the particles are in relation to the particles of the continuous phase, whether or not precipitation occurs, and the presence of Brownian motion. In general, dispersions of particles sufficiently large for sedimentation are called suspensions, while those of smaller particles are called colloids and solutions.
  • 3.0K
  • 11 Oct 2022
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