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Topic Review
IBM Hexadecimal Floating Point
IBM System/360 computers, and subsequent machines based on that architecture (mainframes), support a hexadecimal floating-point format (HFP). In comparison to IEEE 754 floating-point, the IBM floating-point format has a longer significand, and a shorter exponent. All IBM floating-point formats have 7 bits of exponent with a bias of 64. The normalized range of representable numbers is from 16−65 to 1663 (approx. 5.39761 × 10−79 to 7.237005 × 1075). The number is represented as the following formula: (−1)sign × 0.significand × 16exponent−64.
  • 3.2K
  • 09 Oct 2022
Topic Review
Abandoned Croplands in South Africa
There is no standardised definition of agricultural land abandonment; however, a simple definition is the cessation of agricultural activities on a given surface of land. The term agricultural land abandonment is inclusive of land previously used for crops, vegetables, fruit trees, and cultivated and natural pastures. Other agricultural land abandonment studies specifically focus on crops, hence terms such as cropland abandonment, formerly arable lands, and old arable lands or fields are used. Others specify that for the land to qualify as abandoned, it should not be used for any other activity such as urbanisation or afforestation. Therefore, in the context of the rural areas of Africa wherein the cessation of cropping the land is used for grazing, the definition of cropland abandonment suffices. Baxter and Calvert define cropland abandonment as a process of withdrawing cropland from active agricultural production without a plan for crop cultivation in the immediate future. The cessation is usually due to a decline in economic viability even after changes in farming practices. Cessation results in natural succession wherein grasses, shrubs, and trees colonise former cropping lands; it can also result in land degradation. In the former homeland communal areas of South Africa, where the main agricultural activity involves cropping and livestock production, by default if the land is not used for cropping it turns into a grazing area. The same trend of abandoned cropping lands being used for grazing was also reported in Botswana. Therefore, the definition of abandoned cropping land is land mainly used for grazing. The areas are sometimes also called old fields, fallow, or idle fields. Some have turned to be secondary grasslands.
  • 3.2K
  • 25 May 2022
Topic Review
Intersphincteric Resection for Low Rectal Cancers
Intersphincteric resection is an anus-preserving technique for low rectal cancers described by Schiessel et al. in 1994 as a combination of two techniques: the intersphincteric rectal excision for inflammatory bowel disease and the coloanal anastomosis for low rectal resections.
  • 3.2K
  • 08 Oct 2021
Topic Review
Marine-Derived Phenolic Compounds
Phenolic metabolites are organic compounds with at least one or more hydroxyl groups attached to arylic systems with simple variations to highly polymerized molecules.
  • 3.2K
  • 10 Mar 2022
Topic Review
Flash-Boiling Atomization
Flash-boiling atomization is a method by which a liquid is brought into a superheated state, such as vigorous boiling, in a short timeframe while the bubbles grow considerably fast. This leads to the disintegration of the continuous liquid into tiny droplets. Flash-boiling, effervescent, and air-assisted atomization are based on a two-phase flow to achieve effective atomization. 
  • 3.2K
  • 07 Oct 2023
Topic Review
Harvesting and Processing Techniques on Black Tea Quality
Tea (Camellia sinensis) has grown for over 300 years and is recognized worldwide as among other well-renowned crops. The quality of black tea depends on plucking (method, standard, season, and intervals), withering and rolling (time and temperature), fermentation (time, temperature, and RH), drying (temperature and method), and storage conditions, which have a high influence on the final quality of black tea. At the rolling stage, the oxidation process is initiated and ends at the early drying stage until the enzymes that transform tea polyphenols into thearubigins (TRs) and theaflavins (TFs) are denatured by heat. By increasing fermentation time, TRs increased, and TF decreased. Each is liable for black tea’s brightness, taste, and color. 
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  • 29 Dec 2023
Topic Review
Self-Discharge of Batteries
Self-discharge of batteries is a natural, but nevertheless quite unwelcome, phenome­non. Be­cause it is driven in its various forms by the same thermodynamic forces as the discharge dur­ing intended op­era­tion of the device it can only be slowed down by impeding the reaction kinet­ics of its vari­ous steps, i.e. their respective rates of reaction. This approach should be based on a deeper understanding of the various modes and mechanisms of self-discharge, which in turn de­pend on the battery chemistry, its mode of op­eration and environmental conditions. Typical exam­ples from representative battery chemis­tries are presented and observed effects are reviewed. As an outcome of a better understanding ap­proaches to reduce self-discharge are presented.
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  • 22 Feb 2023
Topic Review
Liquid Crystal Aided Nanotechnology/Nanoscience
The research field of liquid crystals and their applications is recently changing from being largely focused on display applications and optical shutter elements in various fields, to quite novel and diverse applications in the area of nanotechnology and nanoscience. Functional nanoparticles, such as ferroelectric and magnetic particles, have recently been used to a significant extent to modify the physical properties of liquid crystals. Also, intriguing photonic functionalities can be realized by adding nanoparticles such as quantum dots, metal particles, semiconductors, etc. into liquid crystals. The self-organization of liquid crystal molecules is exploited to used as order templates to orient nanoparticles. Similarly, anisodiametric nanoparticles such as rods, nanotubes and flakes are shown to form lyotropic liquid crystal phases in the presence of isotropic host solvents at a certain concentration.
  • 3.2K
  • 27 Oct 2020
Topic Review
Pollution of Polyethylene Terephthalate Water Bottles
According to studies on global plastic manufacturing and the resulting pollution, plastic wastes have been identified as a serious environmental concern. The impact of plastic garbage on marine species, humans, and the environment is a source of public concern, necessitating the need to save ecosystems and the lives that depend on them. Polyethylene terephthalate (PET) water bottles have a significant carbon footprint and represent tremendous waste. In the United Arab Emirates (UAE), PET water bottles are widely utilized, with yearly consumption reaching 450 water bottles per person. 
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  • 27 Apr 2022
Topic Review
Enzyme Immobilization Techniques
Researchers have explored the technique of enzyme immobilization as a means to overcome limitations that free enzymes encounter, including reduced performance, high costs, and impracticality for large-scale applications. Enzymatic treatment offers a sustainable and eco-friendly alternative to conventional physicochemical treatment methods, such as adsorption, coagulation, and advanced oxidation processes. Free enzymes are biodegradable, highly efficient, and selective biological catalysts that can operate under mild conditions, thus reducing energy consumption and minimizing the generation of harmful byproducts.
  • 3.2K
  • 07 Sep 2023
Topic Review
Use of Glucagon-Like Peptide-1
Glucagon-like peptide-1 (GLP-1) is a human incretin hormone derived from the proglucagon molecule. GLP-1 receptor agonists are frequently used to treat type 2 diabetes mellitus and obesity. However, the hormone affects the liver, pancreas, brain, fat cells, heart, and gastrointestinal tract. The results showed that GLP-1 agonists can benefit defined off-medication motor scores in Parkinson’s Disease and improve emotional well-being. In Alzheimer’s disease, GLP-1 analogs can improve the brain’s glucose metabolism by improving glucose transport across the blood–brain barrier. In depression, the analogs can improve quality of life and depression scales. GLP-1 analogs can also have a role in treating chemical dependency, inhibiting dopaminergic release in the brain’s reward centers, decreasing withdrawal effects and relapses. These medications can also improve lipotoxicity by reducing visceral adiposity and decreasing liver fat deposition, reducing insulin resistance and the development of non-alcoholic fatty liver diseases. The adverse effects are primarily gastrointestinal. Therefore, GLP-1 analogs can benefit other conditions besides traditional diabetes and obesity uses.
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  • 10 Jul 2022
Topic Review
JASS
JASS and JASS2 (sometimes said to stand for Just Another Scripting Syntax) is a scripting language provided with an event-driven API created by Blizzard Entertainment. It is used extensively by their games Warcraft III (JASS2) and StarCraft (JASS) for scripting events in the game world. Map creators can use it in the Warcraft III World Editor and the Starcraft Editor to create scripts for triggers and AI (artificial intelligence) in custom maps and campaigns. Blizzard Entertainment has replaced JASS with Galaxy in Starcraft II.
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  • 25 Nov 2022
Topic Review
Assisted GPS
Assisted GPS or Augmented GPS (abbreviated generally as A-GPS and less commonly as aGPS) is a system that often significantly improves the startup performance—i.e., time-to-first-fix (TTFF)—of a GPS satellite-based positioning system. A-GPS is extensively used with GPS-capable cellular phones, as its development was accelerated by the U.S. FCC's 911 requirement to make cell phone location data available to emergency call dispatchers.
  • 3.2K
  • 25 Nov 2022
Topic Review
Signalling (Economics)
In contract theory, signalling (or signaling; see spelling differences) is the idea that one party (the agent) credibly conveys some information about itself to another party (the principal). Although signalling theory was initially developed by Michael Spence based on observed knowledge gaps between organisations and prospective employees, its intuitive nature led it to be adapted to many other domains, such as Human Resource Management, business, and financial markets. In Spence's job-market signaling model, (potential) employees send a signal about their ability level to the employer by acquiring education credentials. The informational value of the credential comes from the fact that the employer believes the credential is positively correlated with having the greater ability and difficulty for low ability employees to obtain. Thus the credential enables the employer to reliably distinguish low ability workers from high ability workers. The concept of signaling is also applicable in competitive altruistic interaction, where the capacity of the receiving party is limited.
  • 3.2K
  • 21 Nov 2022
Topic Review
Aether Drag Hypothesis
In the 19th century, the theory of the luminiferous aether as the hypothetical medium for the propagation of light was widely discussed. An important part of this discussion was the question concerning the state of motion of Earth with respect to this medium. The aether drag hypothesis dealt with the question of whether or not the luminiferous aether is dragged by or entrained within moving matter. According to the first variant no relative motion exists between Earth and aether; according to the second one, relative motion exists and thus the speed of light should depend on the speed of this motion ("aether wind"), which should be measurable by instruments at rest on Earth's surface. Specific aether models were invented by Augustin-Jean Fresnel who in 1818 proposed that the aether is partially entrained by matter. The other one was proposed by George Stokes in 1845, in which the aether is completely entrained within or in the vicinity of matter. While Fresnel's almost stationary theory was apparently confirmed by the Fizeau experiment (1851), Stokes' theory was apparently confirmed by the Michelson–Morley experiment (1881, 1887). This contradictory situation was resolved by the works of Hendrik Antoon Lorentz (1895, 1904) whose Lorentz ether theory banished any form of aether dragging, and finally with the work of Albert Einstein (1905) whose theory of special relativity does not contain the aether as a mechanical medium at all.
  • 3.2K
  • 04 Nov 2022
Topic Review
Ice Crystal
Most of the aquatic products are caught from distant seas which make them prone to deterioration and quality losses. One of the main strategies that can be used to increase shelf life and maintain product quality is freezing. During freezing, however, the ice crystals formed may considerably impact the cellular integrity, resulting in loss and degradation of food quality.
  • 3.2K
  • 07 Feb 2021
Topic Review
Free Radical
Free radicals can be defined as molecular entities or molecular fragments, capable of independent existence (hence “free”). They contain one or more unpaired electrons in an outer atomic orbital or molecular orbital (hence “radical”). The negative electrical charge of electron(s) may be counterbalanced by the positive nuclear charge of positrons, resulting in a neutral particle; otherwise, having anion or cation radicals.
  • 3.2K
  • 29 Apr 2022
Topic Review
Advancements in Natural Dyes Extraction
The dyeing and finishing step represents a clear hotspot in the textile supply chain as the wet processing stages require significant amounts of water, energy, and chemicals. In order to tackle environmental issues, natural dyes are gaining attention from researchers as more sustainable alternatives to synthetic ones. The extraction of colorant from natural sources is a fundamental step in preparing purified natural dyes, as a plant’s matrix contains only a small percentage of dye, usually in the range of 0.5–5%, and several other constituents such as water-insoluble fibers, carbohydrates, protein, chlorophyll, and tannins, among others. The selection of the most suitable extraction technique should be based on the evaluation of the nature and solubility of the dyeing materials.
  • 3.2K
  • 28 Aug 2023
Topic Review
Antibody Conjugated Polymeric Nanoparticles
Nanoparticles (NPs) are promising drug delivery systems (DDS) for identifying and treating cancer. Active targeting NPs can be generated by conjugation with ligands that bind overexpressed or mutant cell surface receptors on target cells that are poorly or not even expressed on normal cells. Receptor-mediated endocytosis of the NPs occurs and the drug is released inside the cell or in the surrounding tissue due to the bystander effect. Antibodies are the most frequently used ligands to actively target tumor cells. In this context, antibody-based therapies have been extensively used in HER2+ breast cancer.
  • 3.2K
  • 29 Oct 2020
Topic Review
Chromium
Chromium (Cr) is a common element in the Earth’s crust. It may exist in different oxidation states, Cr(0), Cr(III) and Cr(VI), with Cr(III) and Cr(VI) being relatively stable and largely predominant. Chromium’s peculiarity is that its behavior relies on its valence state. Cr(III) is a trace element in humans and plays a major role in glucose and fat metabolism. The beneficial effects of Cr(III) in obesity and types 2 diabetes are known. It has been long considered an essential element, but now it has been reclassified as a nutritional supplement. On the other hand, Cr(VI) is a human carcinogen and exposure to it occurs both in occupational and environmental contexts. It induces also epigenetic effects on DNA, histone tails and microRNA; its toxicity seems to be related to its higher mobility in soil and swifter penetration through cell membranes than Cr(III). The microorganisms Acinetobacter sp. Cr1 and Pseudomonas sp. Cr13 have been suggested as a promising agent for bioremediation of Cr(VI).
  • 3.2K
  • 22 Feb 2021
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