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COVID-19 and Fake News
COVID-19 can be defined as a global pandemic caused by a coronavirus that first surfaced in 2019. Fake news refers to false reports that can be found in digital media. The combination of these two concepts creates an especially mismanaged situation that can result in widespread unease among the population, to whom the news appears continuously and without quality filters.
  • 3.6K
  • 13 Apr 2022
Topic Review
Sperm Cryopreservation in Ruminant Species
Sperm cryopreservation is a powerful tool to preserve threatened animal species or for livestock breeding. However, this process is not free of disadvantages. Thus, during the cryopreservation process a significant amount of sperm suffers considerable cryodamage, which may affect sperm quality and fertility. Recently, the use of different “omics” technologies in sperm cryobiology, especially proteomics studies, has led to a better understanding of the molecular modifications induced by sperm cryopreservation, facilitating the identification of different freezability biomarkers and certain proteins that can be added before cryopreservation to enhance sperm cryosurvival. This entry provides an updated overview of the molecular mechanism involved in sperm cryodamage, as well as the molecular aspects of those novel strategies that have been developed to reduce sperm cryodamage, including  including new cryoprotectants, antioxidants, proteins, nanoparticles and vitrification.
  • 3.6K
  • 29 Oct 2020
Topic Review
Data Visualization
Data visualization (often abbreviated data viz) is an interdisciplinary field that deals with the graphic representation of data. It is a particularly efficient way of communicating when the data is numerous as for example a time series. From an academic point of view, this representation can be considered as a mapping between the original data (usually numerical) and graphic elements (for example, lines or points in a chart). The mapping determines how the attributes of these elements vary according to the data. In this light, a bar chart is a mapping of the length of a bar to a magnitude of a variable. Since the graphic design of the mapping can adversely affect the readability of a chart, mapping is a core competency of Data visualization. Data visualization has its roots in the field of statistics and is therefore generally considered a branch of descriptive Statistics. However, because both design skills and statistical and computing skills are required to visualize effectively, it is argued by authors such as Gershon and Page that it is both an art and a science. Research into how people read and misread various types of visualizations is helping to determine what types and features of visualizations are most understandable and effective in conveying information.
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  • 20 Oct 2022
Topic Review
List of AMD Athlon Microprocessors
Athlon is the name of a family of CPUs designed by AMD, targeted mostly at the desktop market. It has been largely unused as just "Athlon" since 2001 when AMD started naming its processors Athlon XP, but in 2008 began referring to single core 64-bit processors from the AMD Athlon X2 and AMD Phenom product lines. Later the name began being used for some APUs.
  • 3.6K
  • 26 Oct 2022
Topic Review
BPA Controversy
Bisphenol A controversy centers on concerns and debates about the biomedical significance of bisphenol A (BPA), which is a precursor to polymers that are used in some consumer products, including some food containers. The concerns began with the hypothesis that BPA is an endocrine disruptor, i.e. it mimics endocrine hormones and thus has the unintended and possibly far-reaching effects on people in physical contact with the chemical. Since 2008, several governments have investigated its safety, which prompted some retailers to withdraw polycarbonate products. The U.S. Food and Drug Administration (FDA) ended its authorization of the use of BPA in baby bottles and infant formula packaging, based on market abandonment, not safety. The European Union and Canada have banned BPA use in baby bottles. The U.S. FDA states "BPA is safe at the current levels occurring in foods" based on extensive research, including two more studies issued by the agency in early 2014. The European Food Safety Authority (EFSA) reviewed new scientific information on BPA in 2008, 2009, 2010, 2011 and 2015: EFSA's experts concluded on each occasion that they could not identify any new evidence which would lead them to revise their opinion that the known level of exposure to BPA is safe; however, the EFSA does recognize some uncertainties, and will continue to investigate them. In February 2016, France announced that it intends to propose BPA as a REACH Regulation candidate substance of very high concern (SVHC). The European Chemicals Agency agreed to the proposal in June 2017.
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  • 11 Oct 2022
Topic Review
Melanin regulation peptides
Certain analogs of α-melanocyte stimulating hormone (MSH) and peptides with the sequences derived from the hormone were shown to promote or suppress melanin synthesis in cells and in vivo models. Various amino acids, peptides, their analogs, and their hybrid compounds with other chemical moieties were shown to inhibit tyrosinase (TYR) catalytic activity or downregulate TYR gene expression. Certain peptides were shown to inhibit melanosome biogenesis or induce autophagy, leading to decreased pigmentation. In vivo and clinical evidence are available for some compounds, including [Nle4-D-Phe7]-α-MSH, glutathione disulfide, and glycinamide hydrochloride.
  • 3.6K
  • 28 Sep 2021
Topic Review
Dextran
Dextran is an exopolysaccharide (EPS) synthesized by lactic acid bacteria (LAB) or their enzymes in the presence of sucrose. Dextran is composed of a linear chain of d-glucoses linked by α-(1→6) bonds, with possible branches of d-glucoses linked by α-(1→4), α-(1→3), or α-(1→2) bonds, which can be low (<40 kDa) or high molecular weight (>40 kDa). The characteristics of dextran in terms of molecular weight and branches depend on the producing strain, so there is a great variety in its properties. Dextran has commercial interest because its solubility, viscosity, and thermal and rheological properties allow it to be used in food, pharmaceutical, and research areas. 
  • 3.6K
  • 07 Jul 2021
Topic Review
Technologies in Adaptive Dynamic Building Envelopes
Adaptive Dynamic Building Envelope (ADBE) is the term used to describe envelope systems that increase the adaptability of the building skin toward changing ambient conditions, resulting in better energy efficiency and thermal comfort. ADBEs exploit the benefits of passive and active technologies that manage the energy and mass transfer between building and outdoor environment. There is a range of technologies that an ADBE can incorporate to enhance a building’s energy performance. According to their usage, they can be sorted into four categories, i.e., technologies for energy harvesting, technologies affecting heat transfer, technologies for air conditioning, and technologies for storage systems. ADBEs vary from one another based on their level of active-passiveness, and user controllability. The first characteristic is the level of how active or passive the technologies used in the final ADBE product perform. The second characteristic is the level of occupant interaction with the envelope, meaning if the user has the ability to operate some functions on the ADBE manually, or through the usage of building energy management systems.
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  • 28 Mar 2022
Topic Review
Diet Coke and Mentos Eruption
A Diet Coke and Mentos eruption (also known as a soda geyser) is a reaction between the carbonated beverage Diet Coke and Mentos mints that causes the beverage to spray out of its container. The candies catalyze the release of gas from the beverage, which creates an eruption that pushes most of the liquid up and out of the bottle. Lee Marek and "Marek's Kid Scientists" were the first to publicly demonstrate the experiment on the Late Show with David Letterman in 1999. Steve Spangler's televised demonstration of the eruption in 2005 became popular on YouTube, launching a chain of several other Diet Coke and Mentos experiment viral videos.
  • 3.6K
  • 07 Nov 2022
Topic Review
Structural Components of the Neurovascular Unit
Formulated as a group effort of the stroke community, the transforming concept of the neurovascular unit (NVU) depicts the structural and functional relationship between brain cells and the vascular structure. Composed of both neural and vascular elements, the NVU forms the blood–brain barrier that regulates cerebral blood flow to meet the oxygen demand of the brain in normal physiology and maintain brain homeostasis. Conversely, the dysregulation and dysfunction of the NVU is an essential pathological feature that underlies neurological disorders spanning from chronic neurodegeneration to acute cerebrovascular events such as ischemic stroke and cerebral hemorrhage.
  • 3.6K
  • 29 Sep 2022
Topic Review
Protests Against SOPA and PIPA
On January 18, 2012, a series of coordinated protests occurred against two proposed laws in the United States Congress—the Stop Online Piracy Act (SOPA) and the PROTECT IP Act (PIPA). These followed smaller protests in late 2011. Protests were based on concerns that the bills, intended to provide more robust responses to copyright infringement (also known as piracy) arising outside the United States, contained measures that could possibly infringe online freedom of speech, websites, and Internet communities. Protesters also argued that there were insufficient safeguards in place to protect sites based upon user-generated content. The move to a formal protest was initiated when Fight for the Future organized thousands of the most popular websites in the world, including the English Wikipedia, to temporarily close or interrupt their content and redirect users to a message opposing the proposed legislation. Websites such as Google, Reddit, Mozilla, and Flickr soon featured protests against the acts. Some shut down completely, while others kept some or all of their content accessible. According to Fight for the Future, more than 115,000 websites joined the Internet protest. In addition to the online protests, there were simultaneous physical demonstrations in several U.S. cities, including New York City, San Francisco and Seattle, and separately during December 2011 a mass boycott of then–supporter GoDaddy. The protests were reported globally. The January protest, initially planned to coincide with the first SOPA hearing of the year, drew publicity and reaction. Days prior to the action, the White House issued a statement that it would "not support legislation that reduces freedom of expression, increases cybersecurity risk, or undermines the dynamic, innovative global Internet." On January 18, 2012 itself, more than 8 million people looked up their representative on Wikipedia, 3 million people emailed Congress to express opposition to the bills, more than 1 million messages were sent to Congress through the Electronic Frontier Foundation, a petition at Google recorded over 4.5 million signatures, Twitter recorded at least 2.4 million SOPA-related tweets, and lawmakers collected "more than 14 million names—more than 10 million of them voters—who contacted them to protest" the bills. During and after the January protest, a number of politicians who had previously supported the bills expressed concerns with the proposals in their existing form, while others withdrew their support entirely. Internationally, "scathing" criticism of the bills was voiced from World Wide Web inventor Sir Tim Berners-Lee, as well as the European Commissioner for the Digital Agenda. Some observers were critical of the tactics used; the Boston Herald described the service withdrawals as evidence of "how very powerful these cyber-bullies can be." Motion Picture Association of America Chairman Chris Dodd stated that the coordinated shutdown was "an abuse of power given the freedoms these companies enjoy in the marketplace today." Others such as The New York Times saw the protests as "a political coming of age for the tech industry." By January 20, 2012, the political environment regarding both bills had shifted significantly. The bills were removed from further voting, ostensibly to be revised to take into consideration the issues raised, but according to The New York Times probably "shelved" following a "flight away from the bill". Opposers noted the bills had been "indefinitely postponed" but cautioned they were "not dead" and "[would] return."
  • 3.6K
  • 10 Oct 2022
Topic Review
Artificial Intelligence in Biological Sciences
Artificial intelligence (AI), currently a cutting-edge concept, has the potential to improve the quality of life of human beings. The fields of AI and biological research are becoming more intertwined, and methods for extracting and applying the information stored in live organisms are constantly being refined. As the field of AI matures with more trained algorithms, the potential of its application in epidemiology, the study of host–pathogen interactions and drug designing widens. AI is now being applied in several fields of drug discovery, customized medicine, gene editing, radiography, image processing and medication management. More precise diagnosis and cost-effective treatment will be possible in the near future due to the application of AI-based technologies. In the field of agriculture, farmers have reduced waste, increased output and decreased the amount of time it takes to bring their goods to market due to the application of advanced AI-based approaches. Moreover, with the use of AI through machine learning (ML) and deep-learning-based smart programs, one can modify the metabolic pathways of living systems to obtain the best possible outputs with the minimal inputs. Such efforts can improve the industrial strains of microbial species to maximize the yield in the bio-based industrial setup. 
  • 3.6K
  • 12 Oct 2022
Topic Review
Polyethylene Composites
Polyethylene (PE) is one the most used plastics worldwide for a wide range of applications due to its good mechanical and chemical resistance, low density, cost efficiency, ease of processability, non-reactivity, low toxicity, good electric insulation, and good functionality.
  • 3.6K
  • 10 Feb 2021
Topic Review
Agency
Agency is the capacity of an actor to act in a given environment. It is independent of the moral dimension, which is called moral agency. In sociology, an agent is an individual engaging with the social structure. Notably, though, the primacy of social structure vs. individual capacity with regard to persons' actions is debated within sociology. This debate concerns, at least partly, the level of reflexivity an agent may possess. Agency may either be classified as unconscious, involuntary behavior, or purposeful, goal directed activity (intentional action). An agent typically has some sort of immediate awareness of their physical activity and the goals that the activity is aimed at realizing. In ‘goal directed action’ an agent implements a kind of direct control or guidance over their own behavior.
  • 3.6K
  • 08 Oct 2022
Topic Review
Opuntia ficus-indica (L.) Mill Species
Opuntia ficus-indica (L.) Mill. (OFI) belongs to the Cactaceae family, which contains about 130 genera and nearly 1600 species. This plant is originally from South America, namely Mexico, and can be found in the Middle East, South Africa, India, Australia, and some Mediterranean countries.
  • 3.6K
  • 26 Apr 2023
Topic Review
First-Order Arithmetic
In set theory and mathematical logic, first-order arithmetic is a collection of axiomatic systems formalising natural and subsets of the natural numbers. It is a choice for axiomatic theory as a basis for many mathematics, but not all. The primary first-order axiom is Peano arithmetic, created by Giuseppe Peano: Peano arithmetic has a proof-theoretic ordinal of [math]\displaystyle{ \varepsilon_0 = \varphi(1, 0) = \psi_0(\Omega) }[/math].
  • 3.6K
  • 10 Oct 2022
Topic Review
Gold and Silver Nanoparticle-Based Colorimetric Sensors
Gold and Silver nanoparticles (AuNPs and AgNPs) are perfect platforms for developing sensing colorimetric devices thanks to their high surface to volume ratio and distinctive optical properties, particularly sensitive to changes in the surrounding environment. These characteristics ensure high sensitivity in colorimetric devices. Au and Ag nanoparticles can be capped with suitable molecules that can act as specific analyte receptors, so highly selective sensors can be obtained.
  • 3.6K
  • 23 Nov 2021
Topic Review
Opportunity Assessment: Considerations for Entrepreneurs
Defining entrepreneurship can be problematic and maybe sometimes misleading. For example, the assertion that entrepreneurship is concerned with the discovery and exploitation of profitable opportunities does not appear to take account of the notion of risk, which because of uncertainty is always inherent in new market decisions. This is borne out by reality, where evidence indicates that a large percentage of start-ups (often thought to be between 50% and 70%) fail within the first 5 years. This fact, coupled with research suggesting that idea generation, by itself, is not an issue, implies that the key challenge lies in the effective evaluation of those ideas. This means that entrepreneurs must be honest with themselves and objectively assess whether they have identified a viable business opportunity, as distinct from a good idea with limited or no commercial prospects. This is particularly important for technology entrepreneurs as the lead time to market is often long and the risk of failure is high. Central therefore to the resulting opportunity confidence leading to adoption or rejection of an idea is an iterative process of evaluation, which in the first instance is critical in nascent entrepreneurial processes. Three key constructs—opportunity costs, market assessment and financial analysis—are of singular importance in the evaluation process and are discussed in more detail below. 
  • 3.6K
  • 07 Jan 2022
Topic Review
Eclipse
Eclipse is an integrated development environment (IDE) used in computer programming. It contains a base workspace and an extensible plug-in system for customizing the environment. It is the second-most-popular IDE for Java development, and, until 2016, was the most popular. Eclipse is written mostly in Java and its primary use is for developing Java applications, but it may also be used to develop applications in other programming languages via plug-ins, including Ada, ABAP, C, C++, C#, Clojure, COBOL, D, Erlang, Fortran, Groovy, Haskell, JavaScript, Julia, Lasso, Lua, NATURAL, Perl, PHP, Prolog, Python, R, Ruby (including Ruby on Rails framework), Rust, Scala, and Scheme. It can also be used to develop documents with LaTeX (via a TeXlipse plug-in) and packages for the software Mathematica. Development environments include the Eclipse Java development tools (JDT) for Java and Scala, Eclipse CDT for C/C++, and Eclipse PDT for PHP, among others. The initial codebase originated from IBM VisualAge. The Eclipse software development kit (SDK), which includes the Java development tools, is meant for Java developers. Users can extend its abilities by installing plug-ins written for the Eclipse Platform, such as development toolkits for other programming languages, and can write and contribute their own plug-in modules. Since the introduction of the OSGi implementation (Equinox) in version 3 of Eclipse, plug-ins can be plugged-stopped dynamically and are termed (OSGI) bundles. Eclipse software development kit (SDK) is free and open-source software, released under the terms of the Eclipse Public License, although it is incompatible with the GNU General Public License. It was one of the first IDEs to run under GNU Classpath and it runs without problems under IcedTea.
  • 3.6K
  • 08 Oct 2022
Topic Review
List of Minerals N (Complete)
This list includes those recognised minerals beginning with the letter N. The International Mineralogical Association is the international group that recognises new minerals and new mineral names, however minerals discovered before 1959 did not go through the official naming procedure, although some minerals published previously have been either confirmed or discredited since that date. This list contains a mixture of mineral names that have been approved since 1959 and those mineral names believed to still refer to valid mineral species (these are called "grandfathered" species). The list is divided into groups: The data was exported from mindat.org on 29 April 2005; updated up to 'IMA2018'. The minerals are sorted by name, followed by the structural group (rruff.info/ima and ima-cnmnc by mineralienatlas.de, mainly) or chemical class (mindat.org and basics), the year of publication (if it's before of an IMA approval procedure), the IMA approval and the Nickel–Strunz code.
  • 3.6K
  • 10 Oct 2022
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