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Topic Review
Development of Electrostatic Microactuators
Operation with micrometric size objects requires a change in the entire paradigm in manipulation equipment and particularly in the field of related actuators. Microactuators have low energy efficiency compared to the devices of macroscale. The dimensions of these drives are so small that standard kinematic arrangement is not applicable. On the other hand, the small size allows the use of lower mechanical parameters materials due to the dimensional limits of the micromechanisms. With the development of the biological industry, these actuators became a key for living cell positioning, high-speed microscopy, and other micro-scale technologies. New emerging transducer materials such as magnetic nanoparticles, metallic nanoparticles, expandable micro-spheres, and conductive polymers can be used for the design of micro-scale sensors and actuators. Despite the used materials, the surface effects and inter-molecular interactions are important in micro-scale; in nanoscale, these phenomena become essential. Micro/nanoelectromechanical systems (MEMSs/NEMSs) with electrostatic drives have fast response, are power efficient, and fit well for micro- and nanopositioning. Drive operating voltage, response speed, operating stroke, generated force, and the accumulated amount of energy define these actuators’ application area. The electrostatic actuators suffer from the pull-in phenomenon (loss of the equilibrium between attractive and repulsive forces), limiting their performance. This limitation could be overcome by developing actuators based on repulsive force or electrostatic levitation.
  • 2.9K
  • 26 Aug 2022
Topic Review
Classification of Architected Materials for Additive Manufacturing
One of the main advantages of Additive Manufacturing (AM) is the ability to produce topologically optimized parts with high geometric complexity. In this context, a plethora of architected materials was investigated and utilized in order to optimize the 3D design of existing parts, reducing their mass, topology-controlling their mechanical response, and adding remarkable physical properties, such as high porosity and high surface area to volume ratio.
  • 2.9K
  • 07 Sep 2022
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
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
Chiropractic
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
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
“Singing” Multilayer Ceramic Capacitors and Mitigation Methods
Multilayer Ceramic Capacitors (MLCC) have a major role in modern electronic devices due to their small price and size, large range of capacitance, small ESL and ESR, and good frequency response. Unfortunately, the main dielectric material used for MLCCs, Barium Titanate, makes the capacitors vibrate due to the piezoelectric and electrostrictive effects. This vibration is transferred to the PCB, making it resonate in the audible range of 20 Hz–20 kHz, and in this way the singing capacitors phenomenon occurs. This phenomenon is usually measured with a microphone, to measure the sound pressure level, or with a Laser Doppler Vibrometer (LDV), to measure the vibration. Besides this, other methods are mentioned in the literature, for example, the optical fiber and the active excitation method. There are several solutions to attenuate or even eliminate the acoustic noise caused by MLCC. Specially designed capacitors for low acoustic levels and different layout geometries are only two options found in the literature. To prevent the singing capacitor phenomenon, different simulations can be performed, the harmonic analysis being the most popular technique. 
  • 2.9K
  • 06 Jun 2022
Topic Review
Mycosporine-Like Amino Acids as Sunscreen
Prolonged exposure to harmful ultraviolet radiation (UVR) can induce many chronic or acute skin disorders in humans. To protect themselves, many people have started to apply cosmetic products containing UV-screening chemicals alone or together with physical sunblocks, mainly based on titanium–dioxide (TiO2) or zinc-oxide (ZnO2). However, it has now been shown that the use of chemical and physical sunblocks is not safe for long-term application, so searches for the novel, natural UV-screening compounds derived from plants or bacteria are gaining attention. Certain photosynthetic organisms such as algae and cyanobacteria have evolved to cope with exposure to UVR by producing mycosporine-like amino acids (MAAs). These are promising substitutes for chemical sunscreens containing commercially available sunblock filters. The use of biopolymers such as chitosan for joining MAAs together or with MAA-Np (nanoparticles) conjugates will provide stability to MAAs similar to the mixing of chemical and physical sunscreens. 
  • 2.9K
  • 21 May 2021
Topic Review
E-Consumers in the E-Services Market
In economics, the “consumer” is considered in terms of choice theory, representing the entity that consumes and creates demand. Typically, the term is identified with the purchaser who consumes the products bought and enjoys their use value. In marketing theory, the consumer is the starting point of marketing activities that are undertaken in the market for goods and services. The purpose of these activities is to direct the marketing strategy of producers and sellers to identify the requirements of consumers.
  • 2.9K
  • 25 Feb 2022
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
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
Zend Framework
Zend Framework (ZF) is an open source, object-oriented web application framework implemented in PHP 7 and licensed under the New BSD License. The framework is basically a collection of professional PHP-based packages. The framework uses various packages by the use of Composer as part of its package dependency managers; some of them are PHPUnit for testing all packages, Travis CI for continuous Integration Services. Zend Framework provides to users a support of the Model View Controller (MVC) in combination with Front Controller solution. MVC implementation in Zend Framework has five main areas. The router and dispatcher functions to decide which controller to run based on data from URL, and controller functions in combination with the model and view to develop and create the final web page. On 17 April 2019 it was announced that the framework is transitioning into an open source project hosted by the Linux Foundation to be known as Laminas.
  • 2.9K
  • 01 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
Topic Review
Social Entrepreneurship
Social entrepreneurship (SE) is about entrepreneurial initiatives aimed at exploiting opportunities to generate social value
  • 2.9K
  • 23 Jul 2021
Topic Review
3D-Printed Satellite Brackets
Brackets are the load-bearing components in a satellite. The current age of satellites comprises specific brackets that set out as a link between the bodies of the satellite, reflector parts, and feeder facilities mounted at its upper end. Brackets are used to carry loads of the satellite body frame, supporting elements, batteries, and electronic goods. Additive Manufacturing (AM) is a process in which a 3D solid object is built by adding the material layer-over-layer. The success of making the product using AM technology requires greater experience in Design for Additive Manufacturing (DFAM) which makes use of the design of freedom of AM. Owing to the various advantages of AM and DFAM, it is easy to create high strength-to-weight ratio products. This is an important contribution to aerospace industries in meeting the unabated demand for lightweight and strong structural applications.
  • 2.9K
  • 09 Sep 2022
Topic Review
Husband
A husband is a male in a marital relationship. The rights and obligations of a husband regarding his spouse and others, and his status in the community and in law, vary between cultures and have varied over time. In monogamous cultures, there are only two parties to a marriage. This is enforced by legal codes that outlaw two (bigamy) or more (polygamy) female spouses. Similarly, polyandry, marriage of one female partner with more than one male partner at the same time is not permitted. In polygamous and polyandrous cultures, there may be more than two parties to a marriage. In marriages where both spouses are men, both may be referred to as husband. In heterosexual marriages, the husband was traditionally regarded as the head of the household and was expected to be the sole provider or breadwinner, a role that is still maintained in some cultures (sometimes described as paternalistic). The term continues to be applied to such a man who has separated from his spouse and ceases to be applied to him only when his marriage has come to an end following a legally recognized divorce or the death of his spouse. On the death of his spouse, a husband is referred to as a widower; after a divorce a man may be referred to as the "ex-husband" of his former spouse. In today's society a husband is not necessarily considered the breadwinner of the family, especially if his spouse has a more financially rewarding occupation or career. In such cases, it is not uncommon for a husband to be considered a stay-at-home father if the married couple have children.
  • 2.9K
  • 02 Oct 2022
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
Sexual Racism
Sexual racism is an individual's sexual preference for specific races. It is an inclination towards or against potential sexual or romantic partners on the basis of perceived racial identity. Although discrimination among partners based on perceived racial identity is characterized by some as a form of racism, it is presented as a matter of preference by others. The origins of sexual racism can be explained by looking at its history, especially in the US, where the abolition of slavery and the Reconstruction Era had significant impacts on interracial mixing. Public opinion of interracial marriage and relationships have increased in positivity in the last 50 years. In 1968, 73% of US citizens disapproved of interracial marriage, whereas this figure dropped to 17% by 2007.
  • 2.9K
  • 31 Oct 2022
Topic Review
Travel Website
A travel website is a website on the world wide web that is dedicated to travel. The site may be focused on travel reviews, trip fares, or a combination of both. Approximately 587.3 million consumers are expected to book travel plans online in 2018.
  • 2.9K
  • 25 Nov 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
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