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Topic Review
Micro-Electromechanical Systems
Micro-electromechanical systems (MEMS) technology-based sensors have found diverse fields of application due to the advancement in semiconductor manufacturing technology, which produces sensitive, low-cost, and powerful sensors. Due to the fabrication of different electrical and mechanical components on a single chip and complex process steps, MEMS sensors are prone to deterministic and random errors.
  • 1.7K
  • 21 Mar 2023
Topic Review
Aeroengines’ Bolt Preload Formation Mechanism and Control Technology
The bolt connection structure is widely used in the connection of aeroengine parts, and its connection quality is very important, as it can directly affect the geometric and dynamic performance of the aeroengine. This entry conducts a detailed summary of the aeroengine bolt connection research, in terms of both the tightening mechanism and control technology of bolt connection. It offers a comprehensive review including the tightening mechanism of the single bolt and group bolts, bolt tightening process, and bolt tightening equipment. Besides, the relationship between the tightening mechanism and control technology is summarized. Finally, the future research direction of aeroengine bolt connection through the digital twin is proposed.
  • 1.7K
  • 20 Jul 2023
Topic Review
Tunneling Quantum Dynamics in Ammonia
Ammonia is a well-known example of a two-state system and must be described in quantum-mechanical terms. In this article, we will explain the tunneling phenomenon that occurs in ammonia molecules from the perspective of trajectory-based quantum dynamics, rather than the usual quantum probability perspective.
  • 1.7K
  • 03 Aug 2021
Topic Review
Opuntia (Cactaceae; Opuntioideae) Flower-Visiting Insects
Opuntia species are cacti with high ecological, economic and conservation interest in semiarid environments, particularly in Mexico. Despite the economic and cultural importance of Opuntia, there is a significant lack of knowledge about the flower-visiting insects and their taxonomic identity. Although some Opuntia species could be visited by birds such as hummingbirds, the most dominant taxonomic group of pollinators are the insects. 
  • 1.7K
  • 19 Jan 2022
Topic Review
Psilocybin
Psilocybin, a psychoactive alkaloid contained in hallucinogenic mushrooms, is nowadays given a lot of attention in the scientific community as a research tool for modeling psychosis as well as due to its potential therapeutic effects. Psilocybin was marketed by Sandoz as Indocybin for basic psychopharmacological and therapeutic clinical research, rising in popularity during the 1960s and classified as a Schedule I drug in 1970. Psilocybin is a naturally occurring tryptamine known for its psychedelic properties. Recent research indicates that psilocybin may constitute a valid approach to treat depression and anxiety associated to life-threatening diseases. 
  • 1.7K
  • 23 Sep 2020
Topic Review
Capsaicinoids and Capsiate in Pepper
Capsaicinoids and capsinoids, which are bioactive compounds of interest, are  responsible for the level of pungency of chili peppers, which is one of their most important commercial traits. Both capsaicinoids and capsinoids have received great attention from consumers because of their extensive pharmacological and physiological effects, i.e., antitumor, antioxidant, antiobesity, anti-inflammatory, and analgesic.
  • 1.7K
  • 09 Nov 2020
Topic Review
Avian Pathogenic Escherichia coli (APEC)
Avian pathogenic Escherichia coli (APEC), an extra-intestinal pathogenic E. coli (ExPEC), causes diverse local and systemic infections in poultry, including chickens, turkeys, ducks, and many other avian species. APEC possesses or utilizes different virulence and pathogenesis factors or mechanisms to cause colibacillosis in poultry.
  • 1.7K
  • 17 May 2021
Topic Review
Synthetic Polymers
Unlike natural polymers, the chemical composition, functional group type and extent of functionalization, molecular weight, charge density and distribution, degradation and stability of synthetic polymers can be engineered to maximize antiviral activity against a specific virus type.
  • 1.7K
  • 05 May 2022
Topic Review
Digital Twins’ Applications for Building Energy Efficiency
Over the past, energy efficiency has received increasing attention from the Architecture, Engineering, Construction and Operation (AECO) industry. Digital Twins have the potential to advance the Operation and Maintenance (O&M) phase in different application fields. 
  • 1.7K
  • 14 Oct 2022
Topic Review
2020 in Politics and Government
Events pertaining to world affairs in 2020, national politics, public policy, government, world economics, and international business, that took place in various nations, regions, organizations, around the world in 2020.
  • 1.7K
  • 30 Oct 2022
Topic Review
Fitness
Fitness (often denoted [math]\displaystyle{ w }[/math] or ω in population genetics models) is the quantitative representation of individual reproductive success. It is also equal to the average contribution to the gene pool of the next generation, made by the same individuals of the specified genotype or phenotype. Fitness can be defined either with respect to a genotype or to a phenotype in a given environment or time. The fitness of a genotype is manifested through its phenotype, which is also affected by the developmental environment. The fitness of a given phenotype can also be different in different selective environments. With asexual reproduction, it is sufficient to assign fitnesses to genotypes. With sexual reproduction, recombination scrambles alleles into different genotypes every generation; in this case, fitness values can be assigned to alleles by averaging over possible genetic backgrounds. Natural selection tends to make alleles with higher fitness more common over time, resulting in Darwinian evolution. The term "Darwinian fitness" can be used to make clear the distinction with physical fitness. Fitness does not include a measure of survival or life-span; Herbert Spencer's well-known phrase "survival of the fittest" should be interpreted as: "Survival of the form (phenotypic or genotypic) that will leave the most copies of itself in successive generations." Inclusive fitness differs from individual fitness by including the ability of an allele in one individual to promote the survival and/or reproduction of other individuals that share that allele, in preference to individuals with a different allele. One mechanism of inclusive fitness is kin selection.
  • 1.7K
  • 31 Oct 2022
Topic Review
Th17/Treg Imbalance in Lung Inflammatory Diseases
Regulatory T cells (Tregs) and T helper 17 cells (Th17) are two CD4+ T cell subsets with antagonist effects. Th17 cells promote inflammation, whereas Tregs are crucial in maintaining immune homeostasis. Th17 cells and Treg cells are the foremost players in several inflammatory diseases.
  • 1.7K
  • 03 Apr 2023
Topic Review
Functional Dyspepsia
Functional dyspepsia is a gastrointestinal disorder characterized by postprandial fullness, early satiation, epigastric pain, and epigastric burning. The pathophysiology of the disease is not fully elucidated and there is no permanent cure, although some therapies (drugs or herbal remedies) try to reduce the symptoms.
  • 1.7K
  • 03 Apr 2023
Topic Review
Dhole
The Dhole (Cuon alpinus), also known as the Asiatic wild dog or Indian wild dog, is a formidable and social canid species native to diverse regions of Asia. Recognized for its cooperative hunting strategies and distinctive appearance, the Dhole plays a vital role in the ecosystems it inhabits, despite facing various conservation challenges.
  • 1.7K
  • 04 Feb 2024
Topic Review
Informing Science
Informing science is a transdiscipline that was established to promote the study of informing processes across a diverse set of academic disciplines, including management information systems, education, business, instructional technology, computer science, communications, psychology, philosophy, library science, information science and many others. Its principal unit of analysis is the informing system, a collection of informers, clients, and channels that has been designed or has evolved to serve a particular informing need. The organization created to advance the informing science transdiscipline is the Informing Science Institute (ISI), whose founder, Eli Cohen, proposed the need for the field in his article "Reconceptualizing Information Systems as a Field of the Transdiscipline Informing Science: From Ugly Duckling to Swan" (Cohen, 1999). The ISI presently hosts an annual conference (Informing Science & Information Technology Education (InSITE)), publishes thirteen academic journals, and—through its Informing Science Press—has published dozens of books. Both its journals and books are open access at no cost online, as well as being available for purchase in print form.
  • 1.7K
  • 30 Sep 2022
Topic Review
Regulation of Estrogen Receptor Stability
       Estrogen receptor (ER) signalling promotes proliferation in breast cancer (BCa). Endocrine therapies (ET) target this signaling by preventing the production of its ligand estrogen, or by blocking its interaction with the ER. The ER is regulated by a range of posttranslational modifications (PTMs) including ubiquitylation, SUMOylation, phosphorylation, palmitoylation, acetylation, methylation and glycosylation. These PTMs control ER activity, stability as well as its interactions with other proteins. For example, kinases play significant roles in mediating crosstalk between the ER and the PI3K-AKT-mTOR and MAPK pathways, which are implicated in ET resistance. Another major control of ER activity is through the regulation of its half-life, largely by ubiquitin which initiates degradation through the ubiquitin proteasome system. As such, PTMs play a central role in the regulation of ER activity and stability.
  • 1.7K
  • 08 Oct 2020
Topic Review
Heritage Tourism AR Experiential Value
Augmented reality (AR) provides a multidimensional environment that overlays digital contents on a real environment, allowing visitors to see and receive information while preserving the original state of the site. Experiential value refers to interactions that involved the direct usage or distant appreciation of products and services. A true relationship exists between a tourism destination and AR if the integration of AR into a site exerts a holistic effect on travelers. In this regard, the experiential value of AR is considered important because it relies on the value obtained from the interaction between an individual using AR technology and a dynamic experience element. Therefore, the experiential value of AR in heritage tourism can be a salient antecedent to visitors' perception of new technologies and destinations and their future intentions and behavior.
  • 1.7K
  • 17 Jun 2021
Topic Review
Categorization of Radiation-Hardened-by-Design Flip-Flops
In this review, previously presented RHBD FFs are classified into three categories with an overview ofeach category. Six well-known RHBD FFs architectures are simulated using a 180 nm CMOS processto show a fair comparison between them while the conventional Transmission Gate Flip-Flop (TGFF)is used as a reference design for this comparison. The results of the comparison are analyzed to givesome important highlights about each design.
  • 1.7K
  • 09 Jul 2021
Topic Review
TG-Rich Lipoproteins
Very low-density lipoprotein (VLDL) and chylomicrons, which are known as TG-rich lipoproteins (TRLs), are spherical particles with core lipids (TG and cholesterol esters), phospholipids, free cholesterol, and surface apolipoproteins. The origins of TGs are generally exogenous or endogenous. Exogenous TG is mostly obtained from daily diet and transported within chylomicrons, while endogenous TG circulates in VLDL and is mostly formed in the hepatobiliary system.
  • 1.7K
  • 07 Sep 2021
Topic Review
Froth Flotation
Froth flotation is an important operation for the recovery of valuable minerals in the mining industry. The essence of flotation processes lies in the interactions between particles and bubbles, which can be categorized into three successive sub-processes which are bubble-particle collision, attachment and detachment. These three sub-processes determine the overall performance of flotation processes for treating a particular ore.
  • 1.7K
  • 24 Sep 2021
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