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Topic Review
Abuse of Power
Abuse of power or abuse of authority, in the form of "malfeasance in office" or "official abuse of power", is the commission of an unlawful act, done in an official capacity, which affects the performance of official duties. Malfeasance in office is often a just cause for removal of an elected official by statute or recall election. Officials who utilize abuse of power are often those who exploit the ability to use corruption in their advantage. In the United States, abuse of power has been cited in the impeachment of at least five federal officials. Two of these (Judge George English and President Richard Nixon) resigned before their trial in the Senate could take place, and two others were acquitted by the Senate. The two Senate impeachment trials of President Donald Trump concluded with the president being found not guilty both times. At the state level, Governor Rod Blagojevich of Illinois was impeached and unanimously removed from office by the Illinois Senate in 2009 for offenses including abuse of power.
  • 4.5K
  • 16 Nov 2022
Topic Review
Root Exudates and Soil Organic Carbon
Root exudates, as an important form of material input from plants to the soil, regulate the carbon input and efflux of plant rhizosphere soil and play an important role in maintaining the carbon and nutrient balance of the whole ecosystem. Root exudates are notoriously difficult to collect due to their underlying characteristics (e.g., low concentration and fast turnover rate) and the associated methodological challenges of accurately measuring root exudates in native soils. As a result, up until now, it has been difficult to accurately quantify the soil organic carbon input from root exudates to the soil in most studies. The contribution and ecological effects of root exudates to soil organic carbon input and efflux have been paid more and more attention. 
  • 4.5K
  • 17 Feb 2023
Topic Review
Health-Promoting Beverages
Tea, a beverage made from the processed leaves of the tea plant, Camellia sinensis, and herbal infusions, were primarily consumed to their pleasant taste. Nowadays, are also consumed due to the existence of nutraceutical compounds in the herbs used, such as polyphenols.
  • 4.5K
  • 30 Oct 2020
Topic Review
Properties and Characteristics of C6F12O
In order to cope with the problem that no gas fire suppressant can be used in the future, perfluoro-2-methyl-3-pentanone (C6F12O), also known as FK-5112, Novec 1230 or Novec 649, with its environmentally friendly performance, zero ODP, GWP of approximately one and atmospheric lifetime of up to two weeks (as shown in Table 1), has been considered as the next generation of halon alternatives. C6F12O belongs to fluorinated ketones which is different to HFCs. Its nontoxicity, noncombustibility, excellent insulation properties and fire suppression efficiency have attracted worldwide attention. The thermophysical parameters, safety and environmental issues and other properties such as the dispersion characteristics of C6F12O are important indexes to evaluate whether it is appropriate to replace the halon. Meanwhile, these properties and parameters are critical to determine the application scenes of fire suppressant, the selection of fire extinguishment facilities and the engineering calculation of the fire extinguishment system.
  • 4.5K
  • 18 Apr 2022
Topic Review
East African Lion
The East African lion is a Panthera leo melanochaita population in East Africa. During the 20th century, lion populations in this part of Africa became fragmented and declined in several range countries due to loss of habitat and prey base, poaching and killing of lions to protect livestock and human life. In 2005, a Lion Conservation Strategy was developed for East and Southern Africa. Today, lion populations are stable only in large protected area complexes. The scientific name P. l. melanochaita was proposed for the Cape lion in 1842 that was eradicated in the mid-19th century. P. l. melanochaita differs genetically from P. leo leo; the two subspecies probably diverged at least 50,000 years ago.
  • 4.5K
  • 01 Dec 2022
Topic Review
Nonparametric Limits of Agreement
The assessment of agreement in method comparison and observer variability analysis of quantitative measurements is usually done by the Bland-Altman Limits of Agreement, where the paired differences are implicitly assumed to follow a normal distribution. Whenever this assumption does not hold, the 2.5% and 97.5% percentiles are obtained by quantile estimation. In the literature, empirical quantiles have been used for this purpose. In this simulation study, we applied both sample, subsampling, and kernel quantile estimators as well as other methods for quantile estimation to sample sizes between 30 and 150 and different distributions of the paired differences. The performance of 15 estimators in generating prediction intervals was measured by their respective coverage probability for one newly generated observation. Our results indicated that sample quantile estimators based on one or two order statistics outperformed all the other estimators and can be used for deriving nonparametric Limits of Agreement. For sample sizes exceeding 80 observations, more advanced quantile estimators, such as the Harrell-Davis and estimators of Sfakianakis-Verginis type, which use all the observed differences, performed likewise well, but may be considered intuitively more appealing than simple sample quantile estimators that are based on only two observations per quantile.
  • 4.5K
  • 27 Oct 2020
Topic Review
Messaging Apps
Messaging apps (a.k.a. social messaging or chat applications) are apps and platforms that enable instant messaging. Messaging apps are online messaging services used primarily via mobile platforms. Many such apps have developed into broad platforms enabling status updates, chatbots, payments and conversational commerce (e-commerce via chat). They are normally centralised networks run by the servers of the platform's operators, unlike peer-to-peer protocols like XMPP. Some examples of popular messaging apps include WhatsApp, Facebook Messenger, China's WeChat and QQ Messenger, Telegram, Viber, Line, and Snapchat. The popularity of certain apps greatly differ between different countries. Certain apps have emphasis on certain uses - for example Skype focuses on video calling, Slack focuses on messaging and file sharing for work teams, and Snapchat focuses on image messages. Some social networking services offer messaging services as a component of their overall platform, such as Facebook's Facebook Messenger, while others have a direct messaging function as an additional adjunct component of their social networking platforms, like Instagram, Reddit, Tumblr, TikTok, Clubhouse and Twitter, either directly or through chat rooms. Messaging apps are the most widely used smartphone apps, with in 2018 over 1.3 billion monthly users of WhatsApp and Facebook Messenger, 980 million monthly active users of WeChat and 843 million monthly active users of QQ Mobile.
  • 4.5K
  • 09 Nov 2022
Topic Review
Acetylsalicylic Acid History and Structure
Aspirin (ASA, acetylsalicylic acid ATC code: N02BA01, DrugBank ID: DB00945, brand names: Arthritis Pain, Aspi-Cor, Aspirin 81, Aspirin-Low, Bayer Plus, Bufferin, Ecortin, Eciprin, Miniprin, Vazalore), is one of the first drugs to be obtained by synthesis. It is regarded as, being the most used drug with the longest lasting commercial success.
  • 4.5K
  • 06 Dec 2022
Topic Review
Virtual Power Plant Optimization in Smart Grids
Virtual power plants (VPPs) are promising solutions to address the decarbonization and energy efficiency goals in the smart energy grid. They assume the coordination of local energy resources such as energy generation, storage, and consumption. They are used to tackle problems brought by the stochastic nature of renewable energy, lack of energy storage devices, or insufficient local energy flexibility on the demand side. VPP modeling, management, and optimization are open to research problems that should consider, on one side, the local constraints in the operation of the energy resources and power flows and the energy grid’s sustainability objectives on the other side. There are multiple goals to create a VPP, such as to deliver energy services on a market or to the grid operator, to operate a microgrid in autonomy decoupled from the main grid, or to sustain local energy communities. 
  • 4.5K
  • 27 May 2022
Topic Review
Backbone Chain
In polymer science, the backbone chain of a polymer is the longest series of covalently bonded atoms that together create the continuous chain of the molecule. This science is subdivided into the study of organic polymers, which consist of a carbon backbone, and inorganic polymers which have backbones containing only main group elements. In biochemistry, organic backbone chains make up the primary structure of macromolecules. The backbones of these biological macromolecules consist of central chains of covalently bonded atoms. The characteristics and order of the monomer residues in the backbone make a map for the complex structure of biological polymers (see Biomolecular structure). The backbone is, therefore, directly related to biological molecules’ function. The macromolecules within the body can be divided into four main subcategories, each of which are involved in very different and important biological processes: proteins, carbohydrates, lipids, and nucleic acids. Each of these molecules has a different backbone and consists of different monomers each with distinctive residues and functionalities. This is the driving factor of their different structures and functions in the body. Although lipids have a "backbone," they are not true biological polymers as their backbone is a three carbon molecule, glycerol, with longer substituent "side chains." For this reason, only proteins, carbohydrates, and nucleic acids should be considered as biological macromolecules with polymeric backbones.
  • 4.5K
  • 21 Nov 2022
Topic Review
Postbiological Evolution
Postbiological evolution is a form of evolution which has transitioned from a biological paradigm, driven by the propagation of genes, to a nonbiological (e.g., cultural or technological) paradigm, presumably driven by some alternative replicator (e.g., memes or temes), and potentially resulting in the extinction, obsolescence, or trophic reorganization of the former. Researchers anticipating a postbiological universe tend to describe this transition as marked by the maturation and potential convergence of high technologies, such as artificial intelligence or nanotechnology.
  • 4.5K
  • 25 Nov 2022
Topic Review
Traditional Algal Transformation Techniques
Microalgae and cyanobacteria are photosynthetic microbes that can be grown with the simple inputs of water, carbon dioxide, (sun)light, and trace elements.
  • 4.5K
  • 12 Apr 2021
Topic Review
Kerb Construction
Concrete kerbs can be prepared by precast and cast in situ methods. The precast concrete kerbs can be manufactured by conventional (using a vibrator), dry-pressed and wet-pressed methods and can be installed in almost all weather conditions. Possible rainfall, temperatures and sunlight hours are considered in casting in situ kerbs, and they are more labour-intensive compared to the precast variations. However, cast in situ kerb can better handle sudden changes of direction. There is no study found comparing different aspects of in situ casting and precast kerb. Both types of concrete kerb are suggested for construction by all authorities, such as the Austroads and AASHTO. The precast kerbs require manual placement and have been a major source of workplace injury in the United Kingdom. Past studies have suggested that the use of special lifting equipment (such as vacuum lifters, lifting clamps or stone magnets), reduction in kerb section length, reduction in kerb foundation depth, use of a lightweight or hollow concrete section or other lightweight materials, such as polymer, can reduce the likelihood of such workplace injuries and may also lead to quicker construction as well as better construction quality.
  • 4.5K
  • 28 Mar 2022
Topic Review Peer Reviewed
Benefits of Table Tennis for Brain Health Maintenance and Prevention of Dementia
Table tennis is an extremely popular sport throughout the world as it requires no expensive equipment, specialized amenities, or physical contact among players, and the pace of play can be adapted to allow participation by players of all skill levels, ages, and abilities. It is an aerobic-dominant sport driven primarily by the phosphagen system because rallies are relatively brief (several seconds) and separated by longer rest periods. Several studies have shown that physical interventions including table tennis can help prevent cognitive decline and dementia. Accordingly, the present paper provides an overview of the basic physical and cognitive demands of table tennis, reviews previous studies reporting improvements in physical and brain health across different non-clinical and clinical populations, and critically evaluates the usefulness of table tennis intervention for the prevention of cognitive decline and dementia. This review suggests that table tennis intervention could be a powerful strategy to prevent cognitive decline and dementia in the elderly. 
  • 4.5K
  • 26 Sep 2022
Topic Review
The Mechanisms of Clozapine-Induced Neutropenia
Despite its severe adverse effects, such as agranulocytosis, clozapine is the primary treatment for treatment-resistant schizophrenia. Clozapine is the gold standard for treatment-resistant schizophrenia. It was discovered over a half-century ago by researchers at Wander AG, a Swiss pharmaceutical company. After a decade, the use of clozapine began to fade away due to its alarming side effect but was re-introduced in the year 1989 for the treatment of refractory psychosis. Numerous comparative studies between clozapine and other antipsychotics have reported superior efficacy of clozapine in treatment-resistant schizophrenia.
  • 4.5K
  • 10 Nov 2021
Topic Review
Oxidative Stress in Neurodegenerative Diseases
Neurodegenerative diseases are characterized by gradually progressive, selective loss of anatomically or physiologically related neuronal systems that produce brain damage from which there is no recovery. Neurodegenerative diseases, bridging their clinical differences, are characterized by the gradual and irreversible damage and loss of specific neuronal networks.
  • 4.5K
  • 15 Aug 2022
Topic Review
Benfotiamine
Benfotiamine (BFT) has antioxidant and anti-inflammatory properties that seem to be mediated by a mechanism independent of the coenzyme function of ThDP. BFT has no adverse effects and improves cognitive outcome in patients with mild Alzheimer’s disease (AD). 
  • 4.4K
  • 04 Jun 2021
Topic Review
Xylitol’s Benefits to Skin
Xylitol has been widely documented to have dental health benefits, such as reducing the risk for dental caries. In skin, xylitol has been reported to improve barrier function and suppress the growth of potential skin pathogens. 
  • 4.4K
  • 06 Oct 2021
Topic Review
Nuclear Magnetic Resonance Spectroscopy
A description of standard NMR experiments along with some examples.
  • 4.4K
  • 03 Nov 2020
Topic Review
Dimensionality of materials
As generally known dimensionality of materials is a crucial factor to determine functions and properties of the materials. In addition to zero-dimensional, one-dimensional, three-dimensional, and further integrated functional materials, various two-dimensional materials have been paid special attention. Two-dimensional materials have their unique electronic propertiesand play important roles in interfacial sciences.
  • 4.4K
  • 12 Aug 2021
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