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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
Green Synthetic Approach
Green synthetic protocol refers to the development of processes for the sustainable production of chemicals and materials. For the synthesis of various biologically active compounds, energy-efficient and environmentally benign processes are applied, such as microwave irradiation technology, ultrasound-mediated synthesis, photo-catalysis (ultraviolet, visible and infrared irradiation), molecular sieving, grinding and milling techniques, etc. 
  • 3.2K
  • 01 Jul 2021
Topic Review
Deacetylation
Acetylation (or in IUPAC nomenclature ethanoylation) describes a reaction that introduces an acetyl functional group into a chemical compound. Deacetylation is the removal of an acetyl group. Acetylation refers to the process of introducing an acetyl group (resulting in an acetoxy group) into a compound, namely the substitution of an acetyl group for an active hydrogen atom. A reaction involving the replacement of the hydrogen atom of a hydroxyl group with an acetyl group (CH3CO) yields a specific ester, the acetate. Acetic anhydride is commonly used as an acetylating agent reacting with free hydroxyl groups. For example, it is used in the synthesis of aspirin, heroin, and THC-O-acetate.
  • 3.2K
  • 29 Nov 2022
Topic Review
Sleep in Declarative Memory Consolidation
There is ample evidence supporting a key role of sleep in memory consolidation. Thalamo-cortical and hippocampal-neocortical interactions allow the reconfiguration of synapses. Oscillatory and molecular changes are involved during sleep in memory consolidation and synaptic rescalling.
  • 3.2K
  • 27 Oct 2020
Topic Review
Environmental Monitoring Applications
Concerns about global environmental challenges, such as the alarming increase in pollution of oceans, waterways, land, and air, are becoming more and more prevalent in contemporary society. Environmental pollution has evolved into more than a health concern because of global industrialization and mass consumption patterns; it now represents a danger to whole ecosystems. It is critical to comprehend its causes and mitigation strategies. Adequate and timely environmental data are required for risk forecasting and early warning for environmental disasters.
  • 3.2K
  • 23 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
Prevention and Control Strategies for Maize White Spot
Maize white spot (MWS), caused by the bacterium Pantoea ananatis, is a serious disease that significantly impacts maize production and productivity. Researchers from various countries worldwide have conducted extensive research on this pathogen, including its isolation and identification, the localization of resistance genes, transmission pathways, as well as potential control measures.
  • 3.2K
  • 15 Nov 2023
Topic Review
Sand Cat
The Sand Cat (Felis margarita) is a small wild cat species adapted to desert environments across North Africa, the Middle East, and Central Asia. Renowned for its remarkable ability to thrive in extreme desert conditions, the Sand Cat possesses unique adaptations such as large ears, dense fur, and specialized paw pads to navigate sandy terrain and regulate body temperature. Despite its elusive nature, the Sand Cat plays a crucial role in desert ecosystems as a predator of small rodents and reptiles, contributing to the balance of prey populations and ecosystem dynamics in arid regions.
  • 3.2K
  • 08 Mar 2024
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.
  • 3.2K
  • 10 Jul 2022
Topic Review
Geographic Tongue
Geographic tongue, also known by several other terms, is a condition of the mucous membrane of the tongue, usually on the dorsal surface. It is a common condition, affecting approximately 2–3% of the general population. It is characterized by areas of smooth, red depapillation (loss of lingual papillae) which migrate over time. The name comes from the map-like appearance of the tongue, with the patches resembling the islands of an archipelago. The cause is unknown, but the condition is entirely benign (importantly, it does not represent oral cancer), and there is no curative treatment. Uncommonly, geographic tongue may cause a burning sensation on the tongue, for which various treatments have been described with little formal evidence of efficacy.
  • 3.2K
  • 20 Oct 2022
Topic Review
Chili Pepper Carotenoids: Nutraceutical Properties
Chili pepper is a prominent cultivated horticultural crop that is traditionally used for food seasoning and is applied for the treatment and prevention of multiple diseases. Its beneficial health properties are due to its abundance and variety of bioactive components, such as carotenoids, capsaicinoids, and vitamins. In particular, carotenoids have important nutraceutical properties, and several studies have focused on their potential in the prevention and treatment of human diseases.
  • 3.2K
  • 28 Sep 2021
Topic Review
Electrospinning Process of Electrospun Fibers
Electrospinning is a simple and versatile method to generate nanofibers. Remarkable progress has been made in the development of the electrospinning process. The production of nanofibers is affected by many parameters, which influence the final material properties. Electrospun fibers have a wide range of applications, such as energy storage devices and biomedical scaffolds.
  • 3.2K
  • 24 Aug 2023
Topic Review
Virtual Reality and Robots
There is a significant amount of synergy between virtual reality (VR) and the field of robotics. However, it has only been in approximately the past five years that commercial immersive VR devices have been available to developers. This new availability has led to a rapid increase in research using VR devices in the field of robotics, especially in the development of VR interfaces for operating robots. 
  • 3.2K
  • 25 Jan 2021
Topic Review
Structure and Bonding in Planar Hypercoordinate Carbon Compounds
The term hypercoordination refers to the extent of the coordination of an element by its normal value. In the hypercoordination sphere, the element can achieve planar and/or non-planar molecular shape. Hence, planar hypercoordinate carbon species violate two structural rules: (i) The highest coordination number of carbon is four and (ii) the tetrahedral orientation by the connected elements and/or groups. The unusual planar orientations are mostly stabilized by the electronic interactions of the central atom with the surrounding ligands. Primary knowledge of the planar hypercoordinate chemistry will lead to its forthcoming expansion. Experimental and theoretical interests in planar tetracoordinate carbon (ptC), planar pentacoordinate carbon (ppC), and planar hexacoordinate carbon (phC) are continued. The proposed electronic and mechanical strategies are helpful for the designing of the ptC compounds. Moreover, the 18-valence electron rule can guide the design of new ptC clusters computationally as well as experimentally. However, the counting of 18-valence electrons is not a requisite condition to contain a ptC in a cluster. Furthermore, this ptC idea is expanded to the probability of a greater coordination number of carbon in planar orientations. Unfortunately, until now, there are no such logical approaches to designing ppC, phC, or higher-coordinate carbon molecules/ions. There exist a few global minimum structures of phC clusters identified computationally, but none have been detected experimentally. All planar hypercoordinate carbon species in the global minima may be feasible in the gas phase.
  • 3.2K
  • 26 Dec 2022
Topic Review
Pi Interaction
In chemistry, π-effects or π-interactions are a type of non-covalent interaction that involves π systems. Just like in an electrostatic interaction where a region of negative charge interacts with a positive charge, the electron-rich π system can interact with a metal (cationic or neutral), an anion, another molecule and even another π system. Non-covalent interactions involving π systems are pivotal to biological events such as protein-ligand recognition.
  • 3.2K
  • 07 Dec 2022
Topic Review
Astrophotography
Astrophotography, also known as astronomical imaging, is the photography or imaging of astronomical objects, celestial events, or areas of the night sky. The first photograph of an astronomical object (the Moon) was taken in 1840, but it was not until the late 19th century that advances in technology allowed for detailed stellar photography. Besides being able to record the details of extended objects such as the Moon, Sun, and planets, modern astrophotography has the ability to image objects invisible to the human eye such as dim stars, nebulae, and galaxies. This is done by long time exposure since both film and digital cameras can accumulate and sum photons over these long periods of time. Photography using extended exposure-times revolutionized the field of professional astronomical research, recording hundreds of thousands of new stars, and nebulae invisible to the human eye. Specialized and ever-larger optical telescopes were constructed as essentially big cameras to record images on photographic plates. Astrophotography had an early role in sky surveys and star classification but over time it has given way to more sophisticated equipment and techniques designed for specific fields of scientific research, with image sensors becoming just one of many forms of sensor. Today, astrophotography is mostly a subdiscipline in amateur astronomy, usually seeking aesthetically pleasing images rather than scientific data. Amateurs use a wide range of special equipment and techniques.
  • 3.2K
  • 22 Nov 2022
Topic Review
Ammi Visnaga L.
Ammi visnaga L. (Visnaga daucoides Gaertn., Family Apiaceae), also known as Khella Baldi or toothpick weed, is an annual or biennial herb indigenous to the Mediterranean region of North Africa, Asia, and Europe. Nowadays, it is used in modern medicine to treat many aliments such as renal colic and coronary insufficiency, and is used as an antioxidant, antifungal, and antibacterial, with a larvicidal effect on mosquito larvae. 
  • 3.2K
  • 05 Nov 2021
Topic Review
Pili Torti
Pili torti is a rare condition characterized by the presence of the hair shaft, which is flattened at irregular intervals and twisted 180° along its long axis. It is a form of hair shaft disorder with increased fragility. The condition is classified into inherited and acquired. Inherited forms may be either isolated or associated with numerous genetic diseases or syndromes (e.g., Menkes disease, Björnstad syndrome, Netherton syndrome, and Bazex-Dupré-Christol syndrome). Moreover, pili torti may be a feature of various ectodermal dysplasias (such as Rapp-Hodgkin syndrome and Ankyloblepharon-ectodermal defects-cleft lip/palate syndrome). Acquired pili torti was described in numerous forms of alopecia (e.g., lichen planopilaris, discoid lupus erythematosus, dissecting cellulitis, folliculitis decalvans, alopecia areata) as well as neoplastic and systemic diseases (such as cutaneous T-cell lymphoma, scalp metastasis of breast cancer, anorexia nervosa, malnutrition, cataracts, and chronic graft-vs.-host disease). The condition may also be induced by several drugs (epidermal growth factor receptor inhibitors, oral retinoids, sodium valproate, and carbamide perhydrate). The diagnosis of pili torti is based on trichoscopic or microscopic examination. As pili torti is a marker of numerous congenital and acquired disorders, in every case, the search for the signs of underlying conditions is recommended. 
  • 3.2K
  • 27 Sep 2021
Topic Review
Hyacinthus orientalis L.
Hyacinthus orientalis L., commonly known as hyacinth, is one of the most important cultivated plants around the world. The cultivars of this species are characterised by their flowers with strong fragrances and a wide range of attractive colours, which make them a beloved option among ornamentals. The chloroplast genomes of Hyacinthus cultivars ranged from 154,458 bp to 154,641 bp, while those of Bellevalia paradoxa and Scilla siberica were 154,020 bp and 154,943 bp, respectively. Each chloroplast genome was annotated with 133 genes, including 87 protein-coding genes, 38 transfer RNA genes and 8 ribosomal RNA genes.
  • 3.2K
  • 17 Jun 2022
Topic Review
Verneuil Process
The Verneuil process, also called flame fusion, was the first commercially successful method of manufacturing synthetic gemstones, developed in the late 1800s by the French chemist Auguste Verneuil. It is primarily used to produce the ruby, sapphire and padparadscha varieties of corundum, as well as the diamond simulants rutile and strontium titanate. The principle of the process involves melting a finely powdered substance using an oxyhydrogen flame, and crystallising the melted droplets into a boule. The process is considered to be the founding step of modern industrial crystal growth technology, and remains in wide use to this day.
  • 3.2K
  • 18 Oct 2022
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