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Topic Review

Centaur (Minor Planet)

Centaurs are small solar system bodies with a semi-major axis between those of the outer planets. They generally have unstable orbits because they cross or have crossed the orbits of one or more of the giant planets; almost all their orbits have dynamic lifetimes of only a few million years, but there is one centaur, (514107) 2015 BZ509, which may be in a stable (though retrograde) orbit. Centaurs typically behave with characteristics of both asteroids and comets. They are named after the mythological centaurs that were a mixture of horse and human. It has been estimated that there are around 44,000 centaurs in the Solar System with diameters larger than 1 kilometer. The first centaur to be discovered, under the definition of the Jet Propulsion Laboratory and the one used here, was 944 Hidalgo in 1920. However, they were not recognized as a distinct population until the discovery of 2060 Chiron in 1977. The largest confirmed centaur is 10199 Chariklo, which at 260 kilometers in diameter is as big as a mid-sized main-belt asteroid, and is known to have a system of rings. It was discovered in 1997. However, the lost centaur 1995 SN55 may be somewhat larger. No centaur has been photographed up close, although there is evidence that Saturn's moon Phoebe, imaged by the Cassini probe in 2004, may be a captured centaur that originated in the Kuiper belt. In addition, the Hubble Space Telescope has gleaned some information about the surface features of 8405 Asbolus. (As of 2008), three centaurs have been found to display comet-like comas: 2060 Chiron, 60558 Echeclus, and 166P/NEAT. Chiron and Echeclus are therefore classified as both asteroids and comets. Other centaurs, such as 52872 Okyrhoe, are suspected of having shown comas. Any centaur that is perturbed close enough to the Sun is expected to become a comet.

2.9K
25 Nov 2022

Topic Review

Rheology of Gels and Yielding Liquids

Gels are understood as soft viscoelastic multicomponent solids that are in the incomplete phase separation state, which, under the action of external mechanical forces, do not transit into a fluid state but rupture like any solid material. Gels can “melt” (again, like any solids) due to a change in temperature or variation in the environment. In contrast to this type of rheology, yielding liquids (sometimes not rigorously referred to as “gels”, especially in relation to colloids) can exist in a solid-like (gel-like) state and become fluid above some defined stress and time conditions (yield stress). At low stresses, their behavior is quite similar to that of permanent solid gels, including the frequency-independent storage modulus. The gel-to-sol transition considered in colloid chemistry is treated as a case of yielding. However, in many cases, the yield stress cannot be assumed to be a physical parameter since the solid-to-liquid transition happens in time and is associated with thixotropic effects.

2.9K
28 Sep 2023

Topic Review

Metal Current Collector for LMBs

Lithium Metal Anode (LMA) has been considered as the promising candidate, owing to their high theoretical gravimetric capacity, low electrochemical potential, and low density, to replace the conventional carbon based anode materials of lithium-ion batteries (LIBs). Unfortunately, the inherent hyperactive and volume expansion issues of Lithium (Li) leads to the formation of notorious Li dendrite growth and unstable solid-electrolyte-interphase (SEI), eventually hindering the practical application of lithium metal batteries (LMBs). To resolve this issue, one of the effective approach is to engineer three dimensional (3D) porous metal based Li host owing to their chemical and mechanical stability, high electronic conductivity and low cost. In this review, the challenges and strategies to suppress the Li dendrite growth are presented. Then the design principles and effectiveness of different kinds of metal based Li host to accommodate and buffer the volume expansion of Li for guiding the uniform Li deposition are summarized. Then the special attention is paid to the lithiophilic coating or decoration which can further control the initial Li deposition and lowers the nucleation and voltage overpotential in 3D porous metal framework during Li plating/stripping cycles. Finally, the conclusion and perspective are given on the current status, challenges and future research pathway toward advancement of LMA for dendrite-free and improved battery performance.

2.9K
28 Oct 2020

Topic Review

Protein Intake and Oral Health in Older Adults

Oral health is vital to general health and well-being for all ages, and as with other chronic conditions, oral health problems increase with age. There is a bi-directional link between nutrition and oral health, in that nutrition affects the health of oral tissues and saliva, and the health of the mouth may affect the foods consumed. Evidence suggests that a healthy diet generally has a positive impact on oral health in older adults. Although studies examining the direct link between oral health and protein intake in older adults are limited, some have explored the relationship via malnutrition, which is also prevalent among older adults. Protein–energy malnutrition (PEM) may be associated with poor oral health, dental caries, enamel hypoplasia, and salivary gland atrophy.

2.9K
23 Nov 2022

Topic Review

Chiropractic is a form of alternative medicine mostly concerned with the diagnosis and treatment of mechanical disorders of the musculoskeletal system, especially the spine. Proponents claim that such disorders affect general health via the nervous system, through vertebral subluxation, claims which are demonstrably false. The main chiropractic treatment technique involves manual therapy, especially spinal manipulation therapy (SMT), manipulations of other joints and soft tissues. Its foundation is at odds with mainstream medicine, and chiropractic is sustained by pseudoscientific ideas such as subluxation and "innate intelligence" that reject science. Chiropractors are not medical doctors. Numerous controlled clinical studies of treatments used by chiropractors have been conducted, with conflicting results. Systematic reviews of this research have not found evidence that chiropractic manipulation is effective, with the possible exception of treatment for back pain. A critical evaluation found that collectively, spinal manipulation was ineffective at treating any condition. Spinal manipulation may be cost-effective for sub-acute or chronic low back pain but the results for acute low back pain were insufficient. The efficacy and cost-effectiveness of maintenance chiropractic care are unknown. There is not sufficient data to establish the safety of chiropractic manipulations. It is frequently associated with mild to moderate adverse effects, with serious or fatal complications in rare cases. There is controversy regarding the degree of risk of vertebral artery dissection, which can lead to stroke and death, from cervical manipulation. Several deaths have been associated with this technique and it has been suggested that the relationship is causative, a claim which is disputed by many chiropractors. Chiropractic is well established in the United States, Canada, and Australia. It overlaps with other manual-therapy professions such as osteopathy and physical therapy. Most who seek chiropractic care do so for low back pain. Back and neck pain are considered the specialties of chiropractic, but many chiropractors treat ailments other than musculoskeletal issues. Many chiropractors describe themselves as primary care providers, but the chiropractic clinical training does not support the requirements to be considered primary care providers, so their role on primary care is limited and disputed. Chiropractic has two main groups: "straights", now the minority, emphasize vitalism, "innate intelligence", and consider vertebral subluxations to be the cause of all disease; "mixers", the majority, are more open to mainstream views and conventional medical techniques, such as exercise, massage, and ice therapy. D. D. Palmer founded chiropractic in the 1890s, after saying he received it from "the other world", and his son B. J. Palmer helped to expand it in the early 20th century. Throughout its history, chiropractic has been controversial. Despite the overwhelming evidence that vaccination is an effective public health intervention, among chiropractors there are significant disagreements over the subject, which has led to negative impacts on both public vaccination and mainstream acceptance of chiropractic. The American Medical Association called chiropractic an "unscientific cult" in 1966 and boycotted it until losing an antitrust case in 1987. Chiropractic has had a strong political base and sustained demand for services; in recent decades, it has gained more legitimacy and greater acceptance among conventional physicians and health plans in the United States.

2.9K
02 Dec 2022

Topic Review

Filtration for Water Treatment

In drinking water treatment, filtration plays an important role in the multi-barrier approach employed for the removal of pathogens. The presence of suspended solids and other particulate matter in water increases the resistance of most microbes to disinfection. Therefore, high performance in the removal of particles achieved by granular filtration can increase the disinfection efficiency.

2.9K
27 Jan 2021

Topic Review

Rational Application Developer

Rational Application Developer for WebSphere Software (RAD) is a commercial Eclipse-based integrated development environment (IDE), made by IBM. It provides tools for visually designing, constructing, testing, analyzing, and deploying many types of applications including Java, Java EE, Web 2.0, hybrid mobile, Portal applications, and Web and REST services.

2.9K
19 Oct 2022

Topic Review

In sports, a goal is a physical structure or area where an attacking team must send the ball or puck in order to score points. In several sports, a goal is the sole method of scoring, and thus the final score is expressed in the total number of goals scored by each team. In other sports, a goal may be one of several scoring methods, and thus may be worth a different set number of points than the others. The structure of a goal varies from sport to sport. Most often, it is a rectangular structure that is placed at each end of the playing field. Each structure usually consists of two vertical posts, called goal posts, supporting a horizontal crossbar. A goal line marked on the playing surface between the goal posts demarcates the goal area. Thus, the objective is to send the ball or puck between the goal posts, under or over the crossbar (depending on the sport), and across the goal line. Less commonly, as in basketball or netball, goals are ring-shaped. The structure is often accompanied with an auxiliary net, which stops or slows down the ball when a goal is scored.

2.9K
11 Nov 2022

Topic Review

Role of Naturally Occurring Coumarins in Plants

Coumarins are secondary plant metabolites widely distributed in higher plants, bacteria, fungi, and sponges. This great structural diversity of these natural compounds and their synthesized derivatives enables their wide range of pharmacological activities, such as antioxidant; antibacterial; antifungal; anti-human immunodeficiency infection; anti-tubercular; and anti-cancer activities. There are also many reports about their effectiveness against plant pathogenic pests (phytopathogenic fungi, bacteria, nematodes, and insects).

2.9K
08 Jun 2023

Topic Review

Wetland Systems

We provide here an overview of the use and role of aquatic macrophytes in constructed wetland systems. The ability of plants to remove metals, pharmaceutical products, pesticides, cyanotoxins and nanoparticles in constructed wetlands were compared with the removal effciency of non-planted systems, aiming to evaluate the capacity of plants to increase the removal effciency of the systems. Moreover, this review also focuses on the management and destination of the biomass produced through natural processes of water filtration. The use of macrophytes in constructed wetlands represents a promising technology, mainly due to their effciency of removal and the cost advantages of their implantation. However, the choice of plant species composing constructed wetlands should not be only based on the plant removal capacity since the introduction of invasive species can become an ecological problem.

2.9K
17 Nov 2020

Topic Review

Guided Wave Ultrasonic Testing

Guided wave ultrasonic testing (GWUT) method is an effective method for long-distance inspection of inaccessible and coated structures from a single point of testing. It propagates inspection wave all through the structure without point-to-point scanning, hence, minimizes inspection drudgery and enhances work throughput per day.

2.9K
25 Feb 2021

Topic Review

Automation System to Autonomous System

Autonomy is the core capability of future systems, and architecture design is one of the critical issues in system development and implementation. To discuss the architecture of autonomous systems in the future, this paper reviews the developing progress of architectures from automation systems to autonomous systems. Firstly, the autonomy and autonomous systems in different fields are summarized. The article classifies and summarizes the architecture of typical automated systems and infer three suggestions for building an autonomous system architecture: extensibility, evolvability, and collaborability. Accordingly, this paper builds an autonomous waterborne transportation system, and the architecture is composed of the object layer, cyberspace layer, cognition layer, and application layer, the proposed suggestions made in the construction of the architecture are reflected in the inter-relationships at all layers. Through the cooperation of four layers, the autonomous waterborne transportation system can autonomously complete the system functions, such as system control and transportation service. In the end, the characteristics of autonomous systems are concluded, from which the future primary research directions and the challenges of autonomous systems are provided.

2.9K
17 Jun 2021

Topic Review

From a chemical perspective, gluten has been defined as the proteinaceous mass that remains when wheat dough is washed with water and consists primarily of the prolamin and glutelin fractions of the storage proteins of wheat.

2.9K
24 Aug 2020

Topic Review

Heterogeneous Networks

Communication technologies have drastically increased the number of wireless networks. Heterogeneous networks have now become an indispensable fact while designing the new networks and the way the data packet moves from device to device opens new challenges for transmitting the packet speedily, with maximum throughput and by consuming only confined energy.

2.9K
23 Sep 2022

Topic Review

c-treeACE is a database engine developed by FairCom Corporation. Software developers typically embed the c-treeACE engine within the applications that they create and then deploy the application and engine together as an integrated solution. The most recent edition is c-treeACE V11.5, which was released in November 2017. At its core, c-treeACE uses a record-oriented, Indexed Sequential Access Method (ISAM) structure offering high speed indexing mechanisms over those files. Developers can use these direct access methods to design the data and index structures that closely parallel the needs of their application. This paradigm is sometimes referred to as an application-specific database or an embedded database because of the tightly coupled nature of the application and database. The nature of c-treeACE allows it to be used in a range of products including: embedded systems that require limited disk and memory footprint and silent operation; shrink-wrap products developed by ISVs that require cross-platform support, minimal maintenance, and mass deployment; and enterprise systems that depend on performance and more precision control of database operations than a traditional enterprise database offers. Two versions of the product are available. c-treeACE Express is freely available for development from FairCom's web site and supports only the client/server architecture. The client-side libraries are precompiled, making it easy to use for evaluation. c-treeACE Professional is licensed separately and supports all architectures and includes full source code for the client libraries and much of the source code for the server. c-treeACE is one of few databases that specialize in making data locked into legacy database architecture available to modern APIs while minimizing time, resources and risks involved in modernization projects. c-treeACE combines the benefits of NoSQL such as high performance, low latency and precise data access control, with the flexbility of SQL interfaces.

2.9K
24 Nov 2022

Topic Review

Logical Form (Linguistics)

In some theories of syntax and grammar, in particular in the Chomskyan schools of government and binding theory and the minimalist program, the Logical Form (abbreviated LF and conventionally spelled with capital initial letters) of a linguistic expression is a mental representation of it, derived solely from surface structure. In the words of Noam Chomsky, LF captures "those aspects of semantic representation that are strictly determined by grammar, abstracted from other cognitive systems". It functions as the interface between grammar and conceptual-intentional properties of language, analogous to how the phonetic form (abbreviated PF) is the interface between grammar and the audio-perceptual properties of utterances. Logical Form is the level of representation that affects the semantic interpretation of a sentence. LF is sometimes referred to as a covert level of representation, because the output of this level is not actually pronounced by the speaker. Worth noting is that many theories of syntax do not acknowledge Logical Form (e.g. Lexical Functional Grammar, Head-Driven Phrase Structure Grammar, Dependency Grammars, Tree-Adjoining Grammar, etc.), at least not in the way it is understood in Government and Binding Theory and the Minimalist Program. The postulation of such a level of representation remains a subject of debate.

2.9K
30 Nov 2022

Biography

Yakov Borisovich Zel'dovich

Yakov Borisovich Zel'dovich ForMemRS[1] (Belarusian: Я́каў Бары́савіч Зяльдо́віч, Russian: Я́ков Бори́сович Зельдо́вич; 8 March 1914 – 2 December 1987), also known as YaB,[2] was a Soviet physicist of Belarusian Jewish ethnicity, who is known for his prolific contributions in cosmology and the physics of thermonuclear and hydrodynamical phenome

2.9K
22 Nov 2022

Topic Review

In Windows NT operating systems, a Windows service is a computer program that operates in the background. It is similar in concept to a Unix daemon. A Windows service must conform to the interface rules and protocols of the Service Control Manager, the component responsible for managing Windows services. It is the Services and Controller app, services.exe, that launches all the services and manages their actions, such as start, end, etc. Windows services can be configured to start when the operating system is started and run in the background as long as Windows is running. Alternatively, they can be started manually or by an event. Windows NT operating systems include numerous services which run in context of three user accounts: System, Network Service and Local Service. These Windows components are often associated with Host Process for Windows Services. Because Windows services operate in the context of their own dedicated user accounts, they can operate when a user is not logged on. Prior to Windows Vista, services installed as an "interactive service" could interact with Windows desktop and show a graphical user interface. In Windows Vista, however, interactive services are deprecated and may not operate properly, as a result of Windows Service hardening.

2.9K
13 Oct 2022

Topic Review

Diet and Ganglioside Expression

Gangliosides are series of glycosphingolipids containing sialic acids in the oligosaccharide portion in mammalian cells. Gangliosides are a component of cellular membranes and play roles in modulating membrane function and the activity of membrane proteins. Abnormal expression and metabolism of gangliosides lead to the onset of several conditions in humans, such as neurologic diseases, diabetes, and cancer. A number of studies have been carried out to date to investigate the role of gangliosides in these diseases, and the effect of diet on tissue expression of gangliosides has recently become a topic of interest in this field. As gangliosides are degraded in the intestinal tract, ingested food-derived gangliosides are not directly absorbed into tissues in vivo, but the degradation products can be absorbed and affect ganglioside expression in the tissues. Recent studies have also shown that the expression of gangliosides in tissue cells can be indirectly induced by controlling the expression of ganglioside metabolism-related genes via the diet. These results indicate that dietary control can regulate the expression levels of gangliosides in tissues, which is expected to play a role in preventing and treating ganglioside-related diseases.

2.9K
13 Oct 2021

Topic Review

Graphene oxide (GO) is a chemical compound with a form similar to graphene that consists of one-atom-thick two-dimensional layers of sp2-bonded carbon. Graphene oxide exhibits high hydrophilicity and dispersibility. Thus, it is difficult to be separated from aqueous solutions. Therefore, functionalization with magnetic nanoparticles is performed in order to prepare a magnetic GO nanocomposite that combines the sufficient adsorption capacity of graphene oxide and the convenience of magnetic separation. Moreover, the magnetic material can be further functionalized with different groups to prevent aggregation and extends its potential application. Until today, a plethora of magnetic GO hybrid materials have been synthesized and successfully employed for the magnetic solid-phase extraction of organic compounds from environmental, agricultural, biological, and food samples. The developed GO nanocomposites exhibit satisfactory stability in aqueous solutions, as well as sufficient surface area. Thus, they are considered as an alternative to conventional sorbents by enriching the analytical toolbox for the analysis of trace organic compounds.

2.9K
15 Jan 2021

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