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Topic Review
Community-Based Tourism in Central Asia
Community-based tourism (CBT) is conceived as a form of relatively low-scale tourism that is managed by a group of locally owned businesses to benefit the community and, in some cases, contribute to conservation (when taking place in or near protected areas) . It is marketed as a means of enhancing livelihoods and creating opportunities for community development and is defined as being in, owned, and managed by the community, which receives a sizable portion of the benefits.
  • 2.2K
  • 26 Jul 2022
Topic Review
Biomarkers in Hepatocellular Carcinoma
Hepatocellular carcinoma (HCC) is the most common primary liver cancer and one of the leading causes of cancer-related death worldwide. HCC is highly heterogeneous, both within the tumor and among individuals, which is closely related to the HCC surveillance, diagnosis, prognosis, and treatment response. With the advances of next-generation sequencing, the genomic landscape of HCC has been identified which vastly improves our understanding of genetic and epigenetic changes and their interaction during HCC development.
  • 2.2K
  • 28 Sep 2022
Topic Review
After Dark
After Dark is a series of computer screensaver software introduced by Berkeley Systems in 1989 for the Apple Macintosh, and in 1991 for Microsoft Windows. Following the original, additional editions included More After Dark, Before Dark, and editions themed around licensed properties such as Star Trek, The Simpsons, Looney Tunes, Marvel, and Disney characters. On top of the included animated screensavers, the program allowed for the development and use of third-party modules, many hundreds of which were created at the height of its popularity.
  • 2.2K
  • 02 Nov 2022
Topic Review
Hyperpolarized Carbon-13 MRI
MR spectroscopy (MRS) and spectroscopic imaging (MRSI) obtain metabolic information noninvasively from nuclei spins. For in vivo applications, common MR-active nuclei are protons (1H), phosphorus (31P), carbon (13C), sodium (23Na), and xenon (129Xe). The most common are protons due to their high gyromagnetic ratio and natural abundance in the human body. Since most metabolic processes involve carbon, 13C spectroscopy is a valuable method to measure in vivo metabolism noninvasively [1,2,3]. 13C spectra are characterized by a large spectral range (162–185 ppm), narrow line widths, and low sensitivity due to the low gyromagnetic ratio (a quarter as compared to protons) and natural abundance of 1.1% in vivo. However, the sensitivity can be increased with the use of 13C-enriched agents and by hyperpolarization.Hyperpolarized (HP) 13C MRI is a method that magnetizes 13C probes to dramatically increase signal as compared to conventional MRI [3]. Metabolic and functional HP 13C MRI is a promising diagnostic tool for detecting disorders linked to altered metabolism such as cancer, diabetes, and heart diseases [4], increasing sensitivity sufficiently to map metabolic pathways in vivo without the use of ionizing radiation, as in positron emission tomography (PET) imaging. Metabolic imaging using HP 13C compounds has been translated successfully into single-organ examinations in healthy controls and various patient populations.
  • 2.2K
  • 22 Apr 2021
Topic Review
Microbial-Derived Toll-like Receptor Agonism in Cancer Treatment
Toll-like receptors (TLRs) are typical transmembrane proteins, which are essential pattern recognition receptors in mediating the effects of innate immunity. TLRs recognize structurally conserved molecules derived from microbes and damage-associated molecular pattern molecules that play an important role in inflammation. 
  • 2.2K
  • 15 Jul 2022
Topic Review
Biological Control of Bulb Mites
Mites of the genus Rhizoglyphus (Acari: Acaridae) are serious pests of plants belonging to the orders Liliales and Asparagales such as onions, garlic, lilies, and tulips. Their control by synthetic pesticides is becoming problematic as a result of resistance development in these mites and environmental and health issues. New pest control methods thus need to be developed. Efforts to develop biological control programs for bulb mites have taken place in a number of countries. Several biocontrol agents have been tested against Rhizoglyphus spp. under laboratory and some also under field conditions. The most promising results have been obtained with acaropathogenic/entomopathogenic fungi and predatory mites as described below. Other possible prospective control agents attacking mites are viruses, bacteria, and protista, but except for some bacteria their efficacy against bulb mites has not been investigated yet.
  • 2.2K
  • 29 Jul 2022
Topic Review
Optimal Properties of the Scaffold
Osteoarthritis leads to the progressive decay of articular cartilage. Due to its intrinsic avascular character, cartilage shows an inadequate capacity for regeneration. Cartilage loss may result in chronic pain, movement disorder and morbidity, which lack effective treatments except for joint replacement for late-stage osteoarthritis. To overcome this challenge, tissue engineering has emerged as a promising method. Scaffolds provide mechanical and biochemical support to stem cells that undergo differentiation and secrete a cartilage-specific matrix, and this strategy has been proven to have positive results. The ideal 3D scaffolds need to have versatile properties to mediate cell–cell signalling and cell–matrix interactions for controlling the cellular behaviour of MSCs, specifically: (1) sufficient mechanical strength; (2) biocompatibility; (3) suitable surface morphology for cell attachment; (4) appropriate porosity and pore size to allow the cells to infiltrate as well as nutrients and waste to diffuse; (5) promoting cell proliferation, differentiation and maintenance of a chondrogenic phenotype of seeded cells; (6) capability of integrating with native tissues; and (7) controlled degradation without toxic byproducts.
  • 2.2K
  • 09 Sep 2022
Topic Review
Bitcoin Cash
Bitcoin Cash is a cryptocurrency that is a fork of Bitcoin. Bitcoin Cash is a spin-off or altcoin that was created in 2017. In November 2018, Bitcoin Cash split further into two cryptocurrencies: Bitcoin Cash and Bitcoin SV.
  • 2.2K
  • 21 Oct 2022
Topic Review
The Sumoylation Pathway
Post-translational modifications (PTMs) are key regulators of most biological processes. Besides phosphorylation, methylation, acetylation and others, covalent modification of proteins by small polypeptides of the ubiquitin-like modifiers (UBLs) family have gained importance. Among UBLs, the small ubiquitin-like modifier (SUMO), of ~90 amino acids and discovered in the nineties, has proven to regulate most cellular processes. The sumoylation pathway is quite similar to the ubiquitination pathway, but there is its own set of enzymes for modification by SUMO.
  • 2.2K
  • 25 Jul 2022
Topic Review
Art-sRNAi for Enhanced Antiviral Resistance
Artificial small RNAs (art-sRNAs) are 21-nucleotide small RNAs designed to recognize and silence complementary target RNAs with high specificity. Art-sRNA-based RNAi (art-sRNAi) tools are extensively used in gene function studies or for improving crops. In particular, numerous studies have reported the successful application of art-sRNAi tools to induce resistance against a large number of RNA and DNA viruses in model and crop species. However, the application of art-sRNAi as an antiviral tool has limitations, such as the difficulty to predict the efficacy of a particular art-sRNA, or the emergence of virus variants with mutated target sites escaping to art-sRNA-mediated degradation. Here, we describe the different classes, features and recent uses of art-sRNAi tools to induce enhanced antiviral resistance in plants. 
  • 2.2K
  • 09 Jul 2020
Topic Review
Incretin Hormones
The term incretin was introduced in 1932 to describe compounds produced by intestinal mucosa in response to nutrient ingestion, which were capable of reducing blood glucose. There are two known incretins: glucose-dependent insulinotropic polypeptide (GIP) produced by the K cells of an upper gut and glucagon-like peptide-1 (GLP-1) produced by the L cells of a lower gut. Incretins play a crucial role in stimulating insulin and glucagon secretion by the pancreas.
  • 2.2K
  • 18 Mar 2021
Topic Review
Brass Alloys against Hospital-Acquired Infections
Touch surfaces made of copper-based alloys such as brasses are used in healthcare settings in an attempt to reduce the bioburden and limit environmental transmission of nosocomial pathogens. 
  • 2.2K
  • 22 Apr 2021
Topic Review
Oil Palm and Machine Learning
Machine learning (ML) offers new technologies in the precision agriculture domain with its intelligent algorithms and strong computation. Oil palm is one of the rich crops that is also emerging with modern technologies to meet global sustainability standards. This entry presents a comprehensive review of research dedicated to the application of ML in the oil palm agricultural industry over the last decade (2011–2020).
  • 2.2K
  • 16 Sep 2021
Topic Review
Abundance of Mycoplankton and Its Ecological Role
Mycoplankton are saprophytic organisms in plankton communities in marine and freshwater ecosystems. They consist of filamentous free-living fungi and yeasts associated with planktonic particles or phytoplankton. Similar to planktonic bacteria, these aquatic fungi play important roles in heterotrophic mineralization and nutrient cycling. Planktonic bacteria can be up to 20 mm in diameter and over 50 mm in length
  • 2.2K
  • 23 May 2022
Topic Review
LC-3
Little Computer 3, or LC-3, is a type of computer educational programming language, an assembly language, which is a type of low-level programming language. It features a relatively simple instruction set, but can be used to write moderately complex assembly programs, and is a theoretically viable target for a C compiler. The language is less complex than x86 assembly but has many features similar to those in more complex languages. These features make it useful for beginning instruction, so it is most often used to teach fundamentals of programming and computer architecture to computer science and computer engineering students. The LC-3 was developed by Yale N. Patt at the University of Texas at Austin and Sanjay J. Patel at the University of Illinois at Urbana–Champaign. Their specification of the instruction set, the overall architecture of the LC-3, and a hardware implementation can be found in the second edition of their textbook. Courses based on the LC-3 and Patt and Patel's book are offered in many computer engineering and computer science departments.
  • 2.2K
  • 22 Nov 2022
Topic Review
Determination of Cholesterol (C27H46O) Levels in Foods
Cholesterol (C27H46O) is a lipid-derived substance found in lipoproteins and cell membranes. It is also one of the main sources for the production of bile acids, vitamin D, and steroid hormones. Today, foods are evaluated by consumers not only according to their taste and nutritional content but also according to their effects on consumer health. For example, many consumers choose foods according to their cholesterol level. The cholesterol in the food can directly affect the blood cholesterol level when consumed, which can lead to cardiovascular diseases. High levels of cholesterol can lead to diet-related human diseases such as cardiac arrest, paralysis, type II diabetes, and cerebral hemorrhage. In societies with high living standards, interest in and consumption of foods that lower or have low cholesterol levels have increased recently. Accordingly, efforts to increase the variety of foods with reduced cholesterol levels are on the rise. This has indirectly led to the accurate measurement of cholesterol levels in blood and food being of great importance. Classical chemical, enzymatic, colorimetric, polarographic, chromatographic, and spectrophotometric methods; enzymatic, nonenzymatic, and electrochemical sensors; and biosensors are used for the determination of cholesterol in foods. 
  • 2.2K
  • 18 Dec 2023
Topic Review
Fiat G.50
The Fiat G.50 Freccia ("Arrow") was a World War II Italian fighter aircraft developed and manufactured by aviation company Fiat. Upon entering service, the type became Italy’s first single-seat, all-metal monoplane that had an enclosed cockpit and retractable undercarriage. On 26 February 1937, the G.50 conducted its maiden flight. During early 1938, the Freccias served in the Regia Aeronautica (the Italian Air Force) and with its expeditionary arm, the Aviazione Legionaria, in Spain, where they proved to be relatively fast and very manoeuvrable in comparison to its adversaries in the theatre. Early in the Second World War, it was determined that the G.50 possessed inadequate armament, comprising a pair of Breda-SAFAT 12.7-mm machine guns. The fighter was extensively used on various fronts by Italy, including in Northern Europe, North Africa, the Balkans, and the Italian mainland. The G.50 commonly came up against the British Hawker Hurricane, which was fast enough to frequently outrun and out-range the Italian opponent. Later models of the fighter had improvements, including a substantial increase in range. The G.50 was exported to several overseas customers, small numbers being flown by the Air Force of the Independent State of Croatia while 35 G.50 fighters were shipped to Finland , where they served with distinction during both the Winter War of 1940 and the Continuation War of 1941–1944 against the Soviet Union. In Finnish service, the type reportedly achieved an unprecedented kill/loss ratio of 33/1.
  • 2.2K
  • 08 Nov 2022
Topic Review
Opto-physiological monitoring
Opto-physiological monitoring (OPM) considers biological tissue  as a set of optical media, study how light interacts within biological tissue, where the optical properties of the latter reflect the mechanical, physical and biochemical functions of the living organism. OPM includes optoelectronic sensor based contact monitoring and image sensor based remote monitoring.
  • 2.2K
  • 27 Oct 2020
Topic Review
Thermoelectric Generators at Low Operating-Temperatures
Thermoelectric generators (TEGs) are a form of energy harvester and eco-friendly power generation system that directly transform thermal energy into electrical energy. The thermoelectric (TE) method of energy harvesting takes advantage of the Seebeck effect, which offers a simple solution for fulfilling the power-supply demand in almost every electronics system. A high-temperature condition is commonly essential in the working mechanism of the TE device, which unfortunately limits the potential implementation of the device.
  • 2.2K
  • 01 Jul 2021
Topic Review
Yerba Mate
Ilex paraguariensis (yerba mate) is a plant species of the holly genus Ilex native to South America from the family Aquifoliaceae and is used for the production of yerba mate infusion. The leaves of the plant are steeped in hot water to make a beverage known as mate.
  • 2.2K
  • 07 Mar 2022
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