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Topic Review
Broadcasting
Broadcasting is the distribution of audio or video content to a dispersed audience via any electronic mass communications medium, but typically one using the electromagnetic spectrum (radio waves), in a one-to-many model. Broadcasting began with AM radio, which came into popular use around 1920 with the spread of vacuum tube radio transmitters and receivers. Before this, all forms of electronic communication (early radio, telephone, and telegraph) were one-to-one, with the message intended for a single recipient. The term broadcasting evolved from its use as the agricultural method of sowing seeds in a field by casting them broadly about. It was later adopted for describing the widespread distribution of information by printed materials or by telegraph. Examples applying it to "one-to-many" radio transmissions of an individual station to multiple listeners appeared as early as 1898. Over the air broadcasting is usually associated with radio and television, though more recently, both radio and television transmissions have begun to be distributed by cable (cable television). The receiving parties may include the general public or a relatively small subset; the point is that anyone with the appropriate receiving technology and equipment (e.g., a radio or television set) can receive the signal. The field of broadcasting includes both government-managed services such as public radio, community radio and public television, and private commercial radio and commercial television. The U.S. Code of Federal Regulations, title 47, part 97 defines "broadcasting" as "transmissions intended for reception by the general public, either direct or relayed". Private or two-way telecommunications transmissions do not qualify under this definition. For example, amateur ("ham") and citizens band (CB) radio operators are not allowed to broadcast. As defined, "transmitting" and "broadcasting" are not the same. Transmission of radio and television programs from a radio or television station to home receivers by radio waves is referred to as "over the air" (OTA) or terrestrial broadcasting and in most countries requires a broadcasting license. Transmissions using a wire or cable, like cable television (which also retransmits OTA stations with their consent), are also considered broadcasts but do not necessarily require a license (though in some countries, a license is required). In the 2000s, transmissions of television and radio programs via streaming digital technology have increasingly been referred to as broadcasting as well.
  • 6.0K
  • 24 Nov 2022
Topic Review
Institutional Entrepreneurship
Institutional entrepreneurship comprises the activities of agents who disrupt existing social institutions or create new ones, often to enable diffusion, especially of radical innovations, in a market. 
  • 6.0K
  • 25 Sep 2020
Topic Review
Proportional Representation
Proportional representation (PR) characterizes electoral systems in which divisions in an electorate are reflected proportionately in the elected body. The concept applies mainly to geographical and political divisions of the electorate. The essence of such systems is that all votes contribute to the result—not just a plurality, or a bare majority. The most prevalent forms of proportional representation all require the use of multiple-member voting districts (also called super-districts), as it is not possible to fill a single seat in a proportional manner. In fact, PR systems that achieve the highest levels of proportionality tend to include districts with large numbers of seats, as large as a province or an entire nation. The most widely used families of PR electoral systems are party-list PR, single transferable vote (STV), and mixed-member PR (MMP). In the European Parliament for instance, each member state has a number of seats that is (roughly) proportional to its population, enabling geographical proportional representation. Almost all European countries also have political proportional representation (ideological proportional representation to the degree that parties honestly describe their goals): When n% of the electorate support a particular political party or set of candidates as their favorite, then roughly n% of seats are allotted to that party or those candidates. According to the ACE Electoral Knowledge Network, some form of proportional representation is used for national lower house elections in 94 countries. Party list PR, being used in 85 countries, is the most widely used. MMP is used in seven lower houses. STV is used in only two: Ireland, since independence in 1922, and Malta, since 1921. STV is also used in the Australian Senate, and can be used for nonpartisan elections such as the city council of Cambridge MA. Due to factors such as electoral thresholds and the use of small constituencies, as well as manipulation tactics such as party splitting and gerrymandering, perfect proportionality is rarely achieved under these systems. Nonetheless, they approximate proportionality much better than other systems. Some jurisdictions use leveling seats to compensate for such factors.
  • 6.0K
  • 14 Oct 2022
Topic Review
Railway Nationalization
Railway nationalization is the act of taking rail transport assets into public ownership. Several countries have at different times nationalized part or all of their railway system. More recently, the international trend has been towards privatization. In some areas, notably Great Britain, resultant problems with track maintenance have led back to a more mixed solution, with a nationalised infrastructure operator but privately run train operating companies. National characteristics influenced the structures under which countries' rail networks developed. Some national railways were always under direct State management, some were State-planned but privately operated (as in France, others were wholly private enterprises lightly regulated (as in Great Britain, Ireland and Spain). Nationalization was therefore a bolder step to take in some countries than in others. While ideology has played a role, so too has the need for systematic reconstruction of vital infrastructure devastated by war, often following a period of State control over private companies initiated during the conflict.
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  • 01 Dec 2022
Topic Review
Metabolic N-Dealkylation and N-Oxidation
Metabolic reactions that occur at alkylamino moieties may provide insight into the roles of these moieties when they are parts of drug molecules that act at different receptors. N-dealkylation of N,N-dialkylamino moieties has been associated with retaining, attenuation or loss of pharmacologic activities of metabolites compared to their parent drugs. Further, N-dealkylation has resulted in clinically used drugs, activation of prodrugs, change of receptor selectivity, and providing potential for developing fully-fledged drugs.
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  • 13 Apr 2021
Topic Review
Process of Metabolomics Analysis
Metabolomics, as a new omics technology, has been widely accepted by researchers and has shown great potential in the field of nutrition and health. The process of metabolomics analysis includes sample preparation and extraction, derivatization, separation and detection, and data processing.
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  • 08 Oct 2022
Topic Review
Online Auction
An online auction is an auction which is held over the internet. Online auctions come in many different formats, but most popularly they are ascending English auctions, descending Dutch auctions, first-price sealed-bid, Vickrey auctions, or sometimes even a combination of multiple auctions, taking elements of one and forging them with another. The scope and reach of these auctions have been propelled by the Internet to a level beyond what the initial purveyors had anticipated. This is mainly because online auctions break down and remove the physical limitations of traditional auctions such as geography, presence, time, space, and a small target audience. This influx in reachability has also made it easier to commit unlawful actions within an auction. In 2002, online auctions were projected to account for 30% of all online e-commerce due to the rapid expansion of the popularity of the form of electronic commerce. Online auctions include business to business (B2B), business to consumer (B2C), and consumer to consumer (C2C) auctions. The largest online auction site is eBay, which was the first to support person-to-person transactions. Other popular examples of online auction sites include WebStore, OnlineAuction and Overstock.
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  • 06 Dec 2022
Topic Review
Child Psychopathology
Child psychopathology refers to the scientific study of mental disorders in children and adolescents. Oppositional defiant disorder, attention-deficit hyperactivity disorder, and autism spectrum disorder are examples of psychopathology that are typically first diagnosed during childhood. Mental health providers who work with children and adolescents are informed by research in developmental psychology, clinical child psychology, and family systems. Lists of child and adult mental disorders can be found in the International Statistical Classification of Diseases and Related Health Problems, 10th Edition (ICD-10), published by the World Health Organization (WHO) and in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), published by the American Psychiatric Association (APA). In addition, the Diagnostic Classification of Mental Health and Developmental Disorders of Infancy and Early Childhood (DC: 0-3R) is used in assessing mental health and developmental disorders in children up to age five.
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  • 11 Oct 2022
Topic Review
Waste Treatment Using Black Soldier Fly
Poor waste management has adverse impacts on the environment and human health. The recent years have seen increasing interest in using black soldier fly (BSF), Hermetia illucens, as an organic waste converter. Black soldier fly larvae (BSFL) feed voraciously on various types of organic waste, including food wastes, agro-industrial by-products, and chicken and dairy manure, and reduce the initial weight of the organic waste by about 50% in a shorter period than conventional composting. The main components of the BSFL system are the larvero, where the larvae feed and grow, and the fly house, where the adults BSF live and reproduce.
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  • 28 Apr 2022
Topic Review
Fiscal Year
A fiscal year (or financial year, or sometimes budget year) is used in government accounting, which varies between countries, and for budget purposes. It is also used for financial reporting by businesses and other organizations. Laws in many jurisdictions require company financial reports to be prepared and published on an annual basis, but generally do not require the reporting period to align with the calendar year (1 January to 31 December). Taxation laws generally require accounting records to be maintained and taxes calculated on an annual basis, which usually corresponds to the fiscal year used for government purposes. The calculation of tax on an annual basis is especially relevant for direct taxation, such as income tax. Many annual government fees—such as Council rates, license fees, etc.—are also levied on a fiscal year basis, while others are charged on an anniversary basis. Some companies—such as Cisco Systems—end their fiscal year on the same day of the week each year, i.e. the day that is closest to a particular date (for example, the Friday closest to 31 December). Under such a system, some fiscal years will have 52 weeks and others 53 weeks. The calendar year is used as the fiscal year by about 65% of publicly traded companies in the United States and for a majority of large corporations in the UK. It's the case in many countries around the world with a few exceptions, for example, Australia, New Zealand, and Japan. Many universities have a fiscal year which ends during the summer to align the fiscal year with the academic year (and, in some cases involving public universities, with the state government's fiscal year), and because the university is normally less busy during the summer months. In the northern hemisphere this is July to the next June. In the southern hemisphere this is calendar year, January to December. Some media/communication-based organizations use a broadcast calendar as the basis for their fiscal year. The fiscal year is usually denoted by the calendar year in which it ends, so United States federal government spending incurred on 14 November 2022 would belong to fiscal year 2023, operating on a fiscal calendar of October–September.
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  • 11 Oct 2022
Topic Review
A Sustainable Circular Plastics Economy in The Netherlands
The circular economy (CE) has become a key sustainability discourse in the last decade. The Netherlands seeks to become fully circular by 2050 and the EU has set ambitious circularity targets in its CE Action Plan of 2015. The plastics sector, in particular, has gained a lot of attention as it is a priority area of both the EU and Dutch CE policies. However, there has been little research on the different and often contested discourses, governance processes and policy mechanisms guiding the transition to a circular economy and society. There is thus a dominance of technocentric imaginaries, and a general lack of discussion on holistic, and transformative visions, which integrate the full social, political, and ecological implication of a circular future. 
  • 6.0K
  • 02 Mar 2022
Topic Review
Tobacco Products
Tobacco is the agricultural product of the leaves of plants in the genus Nicotiana. All species of Nicotiana contain the addictive drug nicotine—a stimulant and sedative contained in all parts of the plants except the seeds—which occurs in varying amounts depending on the species and variety cultivated. See types of tobacco and curing of tobacco for more information. The vast majority of commercially available tobacco is derived from the species Nicotiana tabacum, although it is also produced from Nicotiana alata, and to a lesser extent Nicotiana clevelandii, Nicotiana longiflora, and Nicotiana rustica, among others. N. rustica in particular contains much more nicotine than N. tabacum and other species of Nicotiana, and forms the basis of a number of unique tobacco products, including several preparations used in Latin American shamanic ceremonies. Once tobacco has been grown, harvested, cured, and processed, it is used to produce a number of different products. These are most often consumable; however, tobacco and the nicotine derived from it are also used to create pesticides. Tobacco products can generally be divided into two types: smoked tobacco (see tobacco smoking) and smokeless tobacco. An expert in tobacco and tobacco products — especially pipes, pipe tobacco, and cigars—including their procurement and sale, is called a tobacconist. The health effects of tobacco consumption are discussed in health effects of tobacco.
  • 6.0K
  • 19 Oct 2022
Topic Review
Sami Drum
A Sami drum is a shamanic ceremonial drum in the culture of the Sami people of Northern Europe. Sami ceremonial drums have two types: a bowl drum in which the drumhead is strapped over a burl, and a frame drum in which the drumhead stretches over a thin ring of bentwood. Both variations are oval-shaped. The drumhead is fashioned from reindeer hide. In Sami shamanism, the noaidi – the Sami shaman – used the drum to get into a trance, or to obtain information from the future or about other places. The drum was held in one hand, and operated with the other hand. While the noaidi was in trance, his free spirit left his body to visit the spiritual world or other places. When used for divination purposes, the drum was used together with a drum hammer and an vuorbi (index or pointer) made of brass or horn. Answers could be interpreted from where the vuorbi stopped on the membrane, and at which symbols. The patterns on the drum membrane reflect the world view of the owner and his family, both in religious and worldly matters, such as reindeer herding, hunting, householding and relations to their neighbours and to the non-Sami community. Many drums were taken out of their use and Sami ownership during the 18th century. A large number of drums were confiscated by Sami missionaries and other officials as a part of an intensified Christian mission towards the Sami. Other drums were bought by collectors. Between 70 and 80 drums are preserved; the largest collection of drums is at the Nordic Museum, Stockholm.
  • 6.0K
  • 27 Oct 2022
Topic Review
Connectivity Architecture
Connectivity architecture connects main functional blocks or entities of a system with well-defined interfaces enabling interoperability, fluent data flows and information sharing in timely manner. Local connectivity architecture defines e.g. the architecture inside an autonomous ship. The wider-scale architecture includes geographically distributed entities such as vessels, databases, and remote operations centers.
  • 6.0K
  • 17 Aug 2020
Topic Review
Dosage Compensation
Dosage compensation is the process by which organisms equalize the expression of genes between members of different biological sexes. Across species, different sexes are often characterized by different types and numbers of sex chromosomes. In order to neutralize the large difference in gene dosage produced by differing numbers of sex chromosomes among the sexes, various evolutionary branches have acquired various methods to equalize gene expression among the sexes. Because sex chromosomes contain different numbers of genes, different species of organisms have developed different mechanisms to cope with this inequality. Replicating the actual gene is impossible; thus organisms instead equalize the expression from each gene. For example, in humans, females (XX) silence the transcription of one X chromosome of each pair, and transcribe all information from the other, expressed X chromosome. Thus, human females have the same number of expressed X-linked genes as do human males (XY), both sexes having essentially one X chromosome per cell, from which to transcribe and express genes. There are three main mechanisms of achieving dosage compensation which are widely documented in the literature and which are common to most species. These include random inactivation of one female X chromosome (as observed in Mus musculus; this is called X-inactivation), a two-fold increase in the transcription of a single male X chromosome (as observed in Drosophila melanogaster), and decreased transcription by half in both of the X chromosomes of a hermaphroditic organism (as observed in Caenorhabditis elegans). These mechanisms have been widely studied and manipulated in model organisms commonly used in the laboratory research setting. A summary of these forms of dosage compensation is illustrated below. However, there are also other less common forms of dosage compensation, which are not as widely researched and are sometimes specific to only one species (as observed in certain bird and monotreme species).
  • 6.0K
  • 31 Oct 2022
Topic Review
Healthy Benefits of Natural Pigments
Natural pigments, including carotenoids, flavonoids and anthocyanidins, determine the attractive color of fruits. These natural pigments are essential secondary metabolites, which play multiple roles in the whole life cycle of plants and are characterized by powerful antioxidant activity. After decades of research and development, multiple benefits of these natural pigments to human health have been explored and recognized and have shown bright application prospects in food, medicine, cosmetics and other industries. 
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  • 17 May 2021
Topic Review
RealSense Depth Sensors
RealSense technology comprises a microprocessor for image processing, a module for creating depth images, an IR emitter, a segment for tracking movements, and depth sensors.
  • 6.0K
  • 09 Mar 2022
Topic Review
Weave Structure and Fabric Properties
Fabric structures are created by interlacing yarns or intermeshing loops to create two-dimensional (2D) flexible materials. The most prevalent structure is woven fabrics, which are made up of two sets of perpendicular yarns that are crossed and interwoven to form a coherent and stable structure.
  • 6.0K
  • 16 Sep 2022
Topic Review
Diagnosis and Management of Onychotillomania
Onychotillomania is defined as repetitive picking or pulling of the nail unit, causing damage to the nail matrix, nail bed, nail plate and/or periungual skin.
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  • 23 Mar 2022
Topic Review
Electric Vehicle Charger Cybersecurity Vulnerabilities
Worldwide growth in electric vehicle use is prompting new installations of private and public electric vehicle supply equipment (EVSE). EVSE devices support the electrification of the transportation industry but also represent a linchpin for power systems and transportation infrastructures. Cybersecurity researchers have identified several vulnerabilities that exist in EVSE devices, communications to electric vehicles (EVs), and upstream services, such as EVSE vendor cloud services, third-party systems, and grid operators. 
  • 6.0K
  • 02 Jun 2022
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