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Topic Review
Soil as a Biological System
I have summarized the in issues discussed in the mini review that I have published in 2020. Starting from the seven grand questions described by Selman Waksman in 1927 I have discussed the main known aspects of soil as a biological system, the main research approaches and one knowledge gap for each question.
  • 1.9K
  • 10 Jul 2020
Topic Review
Water Remediation
Chemical pollution of water has raised great concerns among citizens, lawmakers, and nearly all manufacturing industries. As the legislation addressing liquid effluents becomes more stringent, water companies are increasingly scrutinized for their environmental performance. In this context, emergent contaminants represent a major challenge, and the remediation of water bodies and wastewater demands alternative sorbent materials. One of the most promising adsorbing materials for micropolluted water environments involves cyclodextrin (CD) polymers and cyclodextrin-containing polysaccharides. 
  • 1.9K
  • 22 Feb 2021
Topic Review
Heiner Syndrome and Milk Hypersensitivity
Infants affected by Heiner syndrome (HS) display chronic upper or lower respiratory tract infections, including otitis media or pneumonia. Clinically, gastrointestinal signs and symptoms, anemia, recurrent fever and failure to thrive can be also present. Chest X-rays can show patchy infiltrates miming pneumonia. Clinical manifestations usually disappear after a milk-free diet. The pathogenetic mechanism underlying HS remains unexplained, but the formation of immune complexes and the cell-mediated reaction have been proposed. Patients usually outgrow this hypersensitivity within a few years.
  • 1.9K
  • 23 Jun 2021
Topic Review
MXenes—A New Class of Two-Dimensional Materials
A new class of two-dimensional nanomaterials, MXenes, which are carbides/nitrides/carbonitrides of transition and refractory metals, has been critically analyzed. Since the synthesis of the first family member in 2011 by Yury Gogotsi and colleagues, MXenes have quickly become attractive for a variety of research fields due to their exceptional properties. Despite the fact that this new family of 2D materials was discovered only about ten years ago, the number of scientific publications related to MXene almost doubles every year. Thus, in 2021 alone, more than 2000 papers are expected to be published, which indicates the relevance and prospects of MXenes. 
  • 1.9K
  • 28 Mar 2022
Topic Review
Sleep Duration and Weight Loss
Sufficient sleep is essential for maintaining healthy physical, mental, and emotional functioning. Optimal sleep duration is determined by several intra- and inter-individual characteristics. A duration of 7–9 h of sleep a night is considered appropriate to support good health in adults of 18–60 years of age, with an optimal average of 7.5 h.
  • 1.9K
  • 21 Apr 2022
Topic Review
β-Galactosidase Immobilization for Galacto-Oligosaccharide Production
Much attention has recently been paid to β-Galactosidases (β-D-galactoside galactohidrolase; EC 3.2.1.23), commonly known as lactases, due to the lactose intolerance of the human population and the importance of dairy products in the human diet. This enzyme, produced by microorganisms, is being used in the dairy industry for hydrolyzing the lactose found in milk to produce lactose-free milk (LFM). Conventionally, β-galactosidases catalyze the hydrolysis of lactose to produce glucose and galactose in LFM; however, they can also catalyze transgalactosylation reactions that produce a wide range of galactooligosaccharides (GOS), which are functional prebiotic molecules that confer health benefits to human health. In this field, different works aims to identify novel microbial sources of β-galactosidase for removing lactose from milk with the relative GOS production. Lactase extracted from thermophilic microorganisms seems to be more suitable for the transgalactosylation process at relatively high temperatures, as it inhibits microbial contamination. Different immobilization methods, such as adsorption, covalent attachment, chemical aggregation, entrapment and micro-encapsulation, have been used to synthesize lactose-derived oligosaccharides with immobilized β-galactosidases. 
  • 1.9K
  • 29 Apr 2022
Topic Review
100,000-Year Problem
The 100,000-year problem ("100 ky problem", "100 ka problem") of the Milankovitch theory of orbital forcing refers to a discrepancy between the reconstructed geologic temperature record and the reconstructed amount of incoming solar radiation, or insolation over the past 800,000 years. Due to variations in the Earth's orbit, the amount of insolation varies with periods of around 21,000, 40,000, 100,000, and 400,000 years. Variations in the amount of incident solar energy drive changes in the climate of the Earth, and are recognised as a key factor in the timing of initiation and termination of glaciations. While there is a Milankovitch cycle in the range of 100,000 years, related to Earth's orbital eccentricity, its contribution to variation in insolation is much smaller than those of precession and obliquity. The 100,000-year-problem refers to the lack of an obvious explanation for the periodicity of ice ages at roughly 100,000 years for the past million years, but not before, when the dominant periodicity corresponded to 41,000 years. The unexplained transition between the two periodicity regimes is known as the Mid-Pleistocene Transition, dated to some 800,000 years ago. The related "400,000-year-problem" refers to the absence of a 400,000-year periodicity due to orbital eccentricity in the geological temperature record over the past 1.2 million years. The transition in periodicity from 41,000 years to 100,000 years can now be reproduced in numerical simulations that include a decreasing trend in carbon dioxide and glacially induced removal of regolith, as explained in more detail in the article Mid-Pleistocene Transition.
  • 1.9K
  • 08 Oct 2022
Topic Review
Manned Orbiting Laboratory
The Manned Orbiting Laboratory (MOL), originally referred to as the Manned Orbital Laboratory, was a never-flown part of the United States Air Force 's human spaceflight program, a successor to the canceled Boeing X-20 Dyna-Soar military reconnaissance space plane project. The project was developed from several early Air Force and NASA concepts of crewed space stations to be used for reconnaissance purposes. MOL evolved into a single-use laboratory, with which crews would be launched on 40-day missions and return to Earth using a Gemini B spacecraft, derived from NASA's Project Gemini. The MOL program was announced to the public on 10 December 1963 as an inhabited platform to prove the utility of putting people in space for military missions. Astronauts selected for the program were later told of the reconnaissance mission for the program. The contractor for the MOL was the Douglas Aircraft Company. The Gemini B was externally similar to NASA's Gemini spacecraft, although it underwent several modifications, including the addition of a circular hatch through the heat shield, which allowed passage between the spacecraft and the laboratory. MOL was canceled in 1969, during the height of the Apollo program, when it was shown that uncrewed reconnaissance satellites could achieve the same objectives much more cost-effectively. U.S. space station development was instead pursued with the civilian NASA Skylab (Apollo Applications Program) which flew in the mid-1970s. In the 1970s, the Soviet Union launched three Almaz military space stations, similar in intent to the MOL, but cancelled the program in 1977 for the same reasons. There is a MOL space suit on display at the Oklahoma City Science Museum, presumably never used.
  • 1.9K
  • 11 Oct 2022
Topic Review
Ischemia
Ischemia or ischaemia is a restriction in blood supply to any tissues, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems with blood vessels, with resultant damage to or dysfunction of tissue i.e. hypoxia and microvascular dysfunction. It also means local hypoxia in a given part of a body sometimes resulting from constriction (such as vasoconstriction, thrombosis or embolism). Ischemia comprises not only insufficiency of oxygen, but also reduced availability of nutrients and inadequate removal of metabolic wastes. Ischemia can be partial (poor perfusion) or total blockage. The inadequate delivery of oxygenated blood to the organs must be resolved either by treating the cause of the inadequate delivery or reducing the oxygen demand of the system that needs it. For example, patients with myocardial ischemia have a decreased blood flow to the heart and are prescribed with medications that reduce chronotrophy and ionotrophy to meet the new level of blood delivery supplied by the stenosed so that it is adequate.
  • 1.9K
  • 14 Nov 2022
Topic Review
Function and Components of Telomerase
Telomerase is the only known eukaryotic-specific enzyme with reverse transcriptase activity, which adds telomeric repeats at the ends of linear chromosomes. In this way, it counteracts telomere shortening and cellular replicative senescence. Telomerase consists of a catalytic protein subunit with reverse transcriptase activity (TERT), and an essential RNA component known as telomerase RNA component (TERC) that contains a template for the synthesis of telomeric DNA, as well as additional proteins (dyskerin, NHP2, NOP10 and GAR1 in vertebrates) that play crucial roles in its biogenesis, localization, and regulation. Beside its telomere-elongating activity, a growing number of studies have evidenced non-telomeric functions.
  • 1.9K
  • 20 Dec 2022
Biography
Abraham Alikhanov
Abraham Isahakovich Alikhanov (Alikhanian, Armenian: Աբրահամ Իսահակի Ալիխանյան) (February 20, 1904 – December 8, 1970) was a Soviet Armenian physicist, academic of the USSR Academy of Sciences. He was one of the leaders of the Soviet atomic project.[1][2] In 1945, he founded and became director of the Institute for Theoretical and Experimental Physics. He is known as one
  • 1.9K
  • 29 Dec 2022
Topic Review
Betaine as a Functional Ingredient
Betaine is a non-essential amino acid with proven functional properties and underutilized potential. The most common dietary sources of betaine are beets, spinach, and whole grains. Whole grains—such as quinoa, wheat and oat brans, brown rice, barley, etc.—are generally considered rich sources of betaine. This valuable compound has gained popularity as an ingredient in novel and functional foods due to the demonstrated health benefits that it may provide.
  • 1.9K
  • 21 Jun 2023
Topic Review
Phytochemistry and Pharmacology of Wild Carrot (Daucus carota)
Daucus carota L., a member of the Apiaceae family, comprises 13 subspecies, with one being cultivated (D. carota L. ssp. sativus (Hoffm.) Arcang.) and the remaining being wild. Traditionally, the wild carrot has been recognized for its antilithic, diuretic, carminative, antiseptic, and anti-inflammatory properties and has been employed in the treatment of urinary calculus, cystitis, gout, prostatitis, and cancer. 
  • 1.9K
  • 15 Mar 2024
Topic Review
Quercetin a Natural Therapeutic Candidate
This manuscript was provided as a comprehensive review of the anti-influenza virus effect of quercetin and its derivatives with critical evaluation. We provided different classifications and focused on viral pathogenesis, animal models, human studies, in silico and docking studies and molecular pathways of quercetin and derivatives effects comprehensively which is not included in similar articles. This review is a multidisciplinary collection of cell biology, biotechnology, drug development, and virus investigation.
  • 1.9K
  • 11 Jan 2021
Topic Review
Frankincense Extracts
Boswellia serrata counts among the most intensively studied anti-inflammatory medicinal plants with more than 650 publications recorded in the PubMed literature database up to now. In folk medicine lipophilic frankincense extracts are used as alternatives to anti-inflammatory steroidal drugs (i.e., glucocorticoids) or nonsteroidal anti-inflammatory drugs (NSAIDs) for the treatment of diseases associated with inflammation like rheumatoid arthritis, osteoarthritis, asthma, atopic dermatitis, and inflammatory bowel diseases.
  • 1.9K
  • 11 May 2021
Topic Review
Wireless Sensor Networks based IoT
The WSN based IoT (WSN-IoT) design problems include network coverage and connectivity issues, energy consumption, bandwidth requirement, network lifetime maximization, communication protocols and state of the art infrastructure. In this paper, the authors propose machine learning methods as an optimization tool for regular WSN-IoT nodes deployed in smart city applications. 
  • 1.9K
  • 26 Jul 2021
Topic Review
Pectins and Olive Pectins
Pectins are a component of the complex heteropolysaccharide mixture present in the cell wall of higher plants. Structurally, the pectin backbone includes galacturonic acid to which neutral sugars are attached, resulting in functional regions in which the esterification of residues is crucial. Pectins influence many physiological processes in plants and are used industrially for both food and non-food applications. Pectin-based compounds are also a promising natural source of health-beneficial bioactive molecules. Olives, the fruit of the olive tree, are consumed as part of the healthy Mediterranean diet or processed into olive oil. Pectins from olives have recently emerged as promising compounds with health-beneficial effects. 
  • 1.9K
  • 14 Sep 2021
Topic Review
Radeon HD 6000 Series
The Northern Islands series is a family of GPUs developed by Advanced Micro Devices (AMD) forming part of its Radeon-brand, based on the 40 nm process. Some models are based on TeraScale 2 (VLIW5), some on the new TeraScale 3 (VLIW4) introduced with them. Starting with this family, the former ATI brand was officially discontinued in favor of making a correlation between the graphics products and the AMD branding for computing platforms (the CPUs and chipsets). Therefore, the AMD brand was used as the replacement. The logo for graphics products and technologies also received a minor makeover (using design elements of the 2010 "AMD Vision" logo). Its direct competitor was Nvidia's GeForce 500 Series; they were launched approximately a month apart.
  • 1.9K
  • 12 Oct 2022
Topic Review
Species Affected by Poaching
Species affected by poaching refers both to the effects of illegal hunting and fishing or capturing of wild animals on certain species, and, in a recent usage, the illegal harvesting of wild plant species. The article provides an overview of species currently endangered or impaired by poaching in the Americas, sub-Saharan Africa, and South-East Asia.
  • 1.9K
  • 20 Oct 2022
Topic Review
Epimedium Flavonoids
Epimedium is a classical Chinese herbal medicine, which has been used extensively to treat various diseases, such as sexual dysfunction, osteoporosis, cancer, rheumatoid arthritis, and brain diseases. Flavonoids, such as icariin, baohuoside I, icaritin, and epimedin C, are the main active ingredients with diverse pharmacological activities.
  • 1.9K
  • 23 Oct 2023
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