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Topic Review
Harbour Defence Motor Launch
The harbour defence motor launch (HDML) was a 72 ft (22 m) long British-designed motor vessel used for harbour defence during World War II. Nearly 500 were built by numerous Allied countries during the war. The HDML was designed by W J Holt at the Admiralty in early 1939. During the war HDMLs were constructed, mainly by yacht builders, in the United Kingdom and a number of other allied countries. In view of their later expanded combat roles in some Commonwealth navies some HDMLs were re-designated as "seaward defence motor launches" (SDML) or "seaward defence boats" (SDB).
  • 2.0K
  • 31 Oct 2022
Topic Review
Cecropins Gene Expression
Antimicrobial peptides (AMPs) are naturally occurring molecules that are utilized as an innate immune response in a variety of organisms. AMPs can be constitutively expressed, and/or their transcription may be upregulated following pathogenic infection. Cecropins (Cecs) are insect AMPs, generally active against Gram-negative bacteria and to a lesser extent, Gram-positive bacteria. Some have been demonstrated to also exhibit an antifungal activity as well as anti-inflammatory and anti-tumor properties. Cecs function by associating their N- and C-terminal helices to the cellular membrane. Polar residues interact with the lipid phosphates while the non-polar residues burrow into the membrane. At high concentrations, Cecs form carpet-like structures with detergent-like properties that result in cell death. At low concentrations, Cecs organize into oligomers that form pores through the cellular phospholipid layer, resulting in an electrolyte imbalance that causes cell death. 
  • 2.0K
  • 30 Jul 2020
Topic Review
Histone H1 post-translational modifications
Protein molecules can be further modified after translation. Post-translational modifications (PTMs) are responsible for most of the proteome diversity and often modulate critical protein functions in health and disease. Histone H1 is a chromatin structural protein, which contains many PTMs that may alter chromatin structure and function. In this entry, we present a summary of the post-translational modifications (PTMs) identified, up to date, in histone H1 from lower eukaryotes to humans. We also highlight the use of different proteomic strategies, as well as the technical challenges involved in mapping H1 PTMs.
  • 2.0K
  • 26 Aug 2020
Topic Review
Implications of Gauge-Free Extended Electrodynamics
Recent tests measured an irrotational (curl-free) magnetic vector potential (A) that is contrary to classical electrodynamics (CED). A (irrotational) arises in extended electrodynamics (EED) that is derivable from the Stueckelberg Lagrangian. A (irrotational) implies an irrotational (gradient-driven) electrical current density, J. Consequently, EED is gauge-free and provably unique. EED predicts a scalar field that equals the quantity usually set to zero as the Lorenz gauge, making A and the scalar potential (F) independent and physically-measureable fields. EED predicts a scalar-longitudinal wave (SLW) that has an electric field along the direction of propagation together with the scalar field, carrying both energy and momentum. EED also predicts the scalar wave (SW) that carries energy without momentum.
  • 2.0K
  • 01 May 2021
Topic Review
Leveraging Reddit for Suicidal Ideation Detection
Suicide is a major public-health problem that exists in virtually every part of the world. Hundreds of thousands of people commit suicide every year. The early detection of suicidal ideation is critical for suicide prevention. However, there are challenges associated with conventional suicide-risk screening methods. At the same time, individuals contemplating suicide are increasingly turning to social media and online forums, such as Reddit, to express their feelings and share their struggles with suicidal thoughts. 
  • 2.0K
  • 02 Nov 2022
Topic Review
Pax (Command)
Pax is an archiving utility available for various operating systems and defined since 1995. Rather than sort out the incompatible options that have crept up between tar and cpio, along with their implementations across various versions of Unix, the IEEE designed new archive utility pax that could support various archive formats with useful options from both archivers. The pax command is available on Unix and Unix-like operating systems and on IBM i, Microsoft Windows NT, and Windows 2000. In 2001, IEEE defined a new pax format which is basically tar with additional extended attributes. The format is not supported by pax commands in most Linux distributions and in FreeBSD, but it is supported by tar commands from GNU and FreeBSD; the format is further supported by pax commands in AIX, Solaris and HP-UX. The name "pax" is an acronym for portable archive exchange. The command invocation and structure is somewhat a unification of both tar and cpio.
  • 2.0K
  • 04 Nov 2022
Topic Review
React (Media Franchise)
React (sometimes stylized in all caps as REACT) is a media franchise used by the Fine Brothers consisting of several online series centering on a group of individuals reacting to viral videos, trends, video games, film trailers, or music videos. React was also the first react channel on YouTube. The franchise was launched with the YouTube debut of Kids React in October 2010, and then grew to encompass four more series uploaded on the Fine Brothers' primary YouTube channel, a separate YouTube channel with various reaction-related content, as well as a television series titled React to That. In 2016, the duo announced React World, a program and channel in which they would license the format of their React shows to creators, which led to widespread negative reception from viewers and fellow content creators, as well as confusion about what their format is. This eventually lead to the Fine Brothers to removing all videos related to React World, essentially pulling the plug on the React World program.
  • 2.0K
  • 10 Nov 2022
Topic Review
Olfaction
Olfaction is a chemoreception that, through the sensory olfactory system, forms the perception of smell. Olfaction has many purposes, such as the detection of hazards, pheromones, and food. Olfaction occurs when odorants bind to specific sites on olfactory receptors located in the nasal cavity. Glomeruli aggregate signals from these receptors and transmit them to the olfactory bulb, where the sensory input will start to interact with parts of the brain responsible for smell identification, memory, and emotion. Olfactory dysfunction arises as the result of many different peripheral and central disturbances, including upper respiratory infections, traumatic brain injury, and neurodegenerative disease.
  • 2.0K
  • 10 Nov 2022
Topic Review
Secondary Metabolites Produced by Bacillus subtilis Group
The Bacillus subtilis (B. subtilis) group is a ubiquitous Gram-positive bacteria with a remarkable adaptability potential that enables it to survive in highly diverse environments. 
  • 2.0K
  • 10 Mar 2023
Topic Review
Employment and Economic Growth
Based on the Cobb–Douglas production function, researchers developed an employment demand model to find the employment elasticity with respect to economic growth using working hours and population as explanatory variables.
  • 2.0K
  • 21 Aug 2023
Topic Review
System Structure of Appointment Scheduling
In the face of an increasingly high-demand environment for outpatients, achieving a balance between allocation of limited medical resources and patient satisfaction has considerable social and economic benefits. Therefore, appointment scheduling (AS) system operation is used in clinics and hospitals, and its operation optimization research is of great significance.
  • 2.0K
  • 23 Feb 2024
Topic Review
Heart Failure with Preserved Ejection Fraction
Heart failure with preserved ejection fraction (HFpEF) remains a poorly characterized syndrome with many unknown aspects related to different patient profiles, various associated risk factors and a wide range of aetiologies. It comprises several pathophysiological pathways, such as endothelial dysfunction, myocardial fibrosis, extracellular matrix deposition and intense inflammatory system activation.
  • 2.0K
  • 18 Jan 2023
Topic Review
Structure of Blood–Brain Barrier and Substance Transportation
The complex structure of the blood–brain barrier (BBB), which blocks nearly all large biomolecules, hinders drug delivery to the brain and drug assessment, thus decelerating drug development. Conventional in vitro models of BBB cannot mimic some crucial features of BBB in vivo including a shear stress environment and the interaction between different types of cells. There is a great demand for a new in vitro platform of BBB that can be used for drug delivery studies.
  • 2.0K
  • 01 Mar 2023
Topic Review
Level Design
Level design, or environment design, is a discipline of game development involving creation of video game levels—locales, stages, or missions. This is commonly done using a level editor, a game development software designed for building levels; however, some games feature built-in level editing tools.
  • 2.0K
  • 08 Oct 2022
Topic Review
Nano Copper Lubricant Additives
Nanoparticles have as characteristics super sliding, extreme pressure, self-healing, etc., which can improve the friction reduction and anti-wear performance of sliding components, when used as lubricating oil additives. Nano-copper particles have a good synergistic effect with other antifriction agents, anti-wear agents, antioxidants and grease additives because of their low shear strength and grain boundary slip effect, showing a better anti-friction and anti-wear effect. However, nanoparticles are prone to conglomerate, and this causes a bottleneck in the application of dispersant for nano-copper in a lubricating oil system. The regulation of nanosized effect and surface properties has great engineering significance in compensating for the precision in manufacturing accuracy. 
  • 2.0K
  • 19 Apr 2022
Topic Review
Isorhamnetin Glycosides as Phytonutrients
Isorhamnetin glycosides (IGs) are a class of essential flavonoids derived from dietary and medicinal plants such as Opuntia ficus-indica, Hippophae rhamnoides, and Ginkgo biloba.
  • 2.0K
  • 06 May 2023
Topic Review
Sjögren’s Syndrome
Sjögren’s syndrome (SS) is a chronic autoimmune inflammatory disease that affects primarily older women and is characterized by irreversible damage of the exocrine glands, including tear (xerophthalmia) and salivary glands (xerostomia). Secretory glands lose their functionality due to the infiltration of immune cells, which produce cytokines and cause inflammation. Primary SS is characterized by dry syndrome with or without systemic commitment in the absence of other pathologies. Secondary SS is accompanied by other autoimmune diseases with high activation of B lymphocytes and the production of autoantibodies, including the rheumatoid factor. Other cells, such as CD4+ T cells and mast cells (MCs), participate in SS inflammation. MCs are ubiquitous, but are primarily located close to blood vessels and nerves and can be activated early in autoimmune diseases to express a wide variety of cytokines and chemokines. In the SS acute phase, MCs react by generating chemical mediators of inflammation, tumor necrosis factor (TNF), and other pro-inflammatory cytokines such as interleukin (IL)-1 and IL-33.
  • 2.0K
  • 26 Oct 2020
Topic Review
P-Glycoprotein Inhibitors
P-gp inhibitors are compounds that block or bypass P-gp efflux. The concurrent administration of P-gp inhibitors with P-gp substrates can prevent the expulsion of these substrates and increase their therapeutic effects. Researchers have identified, studied, and evaluated various P-gp inhibitors, including small molecules, natural products, and pharmaceutically inert excipients.
  • 2.0K
  • 18 Aug 2021
Topic Review
Fused Filament Fabrication Process
Three-dimensional printing (3DP), also known as additive manufacturing (AM), has rapidly evolved over the past few decades. Researchers around the globe have been putting their efforts into AM processes improvement and materials development. One of the most widely used extrusion-based technology under AM processes is Fused Deposition Modeling (FDM), also known as Fused Filament Fabrication (FFF). Numerical simulation tools are being employed to predict the FFF process complexities and material behavior. These tools allow exploring candidate materials for their potential use in the FFF process and process improvements. The prime objective of this study is to provide a comprehensive review of state-of-the-art scientific achievements in numerical simulations of the FFF process for polymers and their composites.
  • 2.0K
  • 30 Nov 2021
Topic Review
Sesquiterpenoids Specially Produced by Fungi
Fungi are widely distributed in the terrestrial environment, freshwater, and marine habitat. Only approximately 100,000 of these have been classified although there are about 5.1 million characteristic fungi all over the world. These eukaryotic microbes produce specialized metabolites and participate in a variety of ecological functions, such as quorum detection, chemical defense, allelopathy, and maintenance of symbiosis. Fungi therefore remain an important resource for the screening and discovery of biologically active natural products. Sesquiterpenoids are arguably the richest natural products from plants and micro-organisms. The rearrangement of the 15 high-ductility carbons gave rise to a large number of different skeletons. At the same time, abundant structural variations lead to a diversification of biological activity. 
  • 2.0K
  • 06 Dec 2021
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