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Topic Review
MOC and Wood as a Composite Building Material
Magnesium oxychloride cement (MOC) is one of the alternatives, also known as Sorel cement, this type of cement is formed by the reaction of light burned MgO with MgCl2 water solution.
  • 1.4K
  • 28 Mar 2022
Topic Review
Eastern Subterranean Termite
Reticulitermes flavipes, the eastern subterranean termite is the most common termite found in North America. These termites are the most economically important wood destroying insects in the United States and are classified as pests. They feed on cellulose material such as the structural wood in buildings, wooden fixtures, paper, books, and cotton. A mature colony can range from 20,000 workers to as high as 5 million workers and the primary queen of the colony lays 5,000 to 10,000 eggs per day to add to this total.
  • 1.4K
  • 10 Oct 2022
Topic Review
Band Gap Engineering
Crystalline TiO2 (as rutile, anatase or brookite) can absorb only about 4% of the solar energy due to its large band gap in the range of 3.0–3.2 eV. As a consequence, the true incident photon conversion yield of most sun-light and semiconductor-assisted photoreactions is low. The aim of exploiting visible light can be achieved by applying various techniques such as doping or modification with metals and non-metals, coupling of semiconductors, or dye sensitization. Since only the former technique seems to allow cost-efficient and robust synthesis routes for realistic applications of titania coatings, this chapter will concentrate on metal and non-metal doping.
  • 1.4K
  • 19 Oct 2022
Topic Review
Left-Right Asymmetry
Left-right asymmetry (LR asymmetry) refers to differences in structure (symmetry breaking) across the mediolateral (left and right) plane in animals. This plane is defined with respect to the anteroposterior and dorsoventral axes and is perpendicular to both. Because the left-right plane is not strictly an axis (as it is not established through a morphogen gradient), to create asymmetry, the left and right sides need to be patterned separately. LR asymmetry is pervasive throughout metazoans and present throughout every major lineage. Notable examples include the large and small claws of the fiddler crab, the left offset of the vertebrate heart, asymmetrical gut coiling in Drosophila melanogaster, and dextral (clockwise) and sinistral (counterclockwise) coiling of gastropods. This asymmetry can be restricted to a specific organ or feature, as in the crab claws, or be expressed throughout the entire body as in snails.
  • 1.4K
  • 02 Nov 2022
Topic Review
Role of Gut Microbiome in Cow’s Milk Allergy
Cow’s milk allergy (CMA) is the most prevalent food allergy (FA) in infancy and early childhood and can be present with various clinical phenotypes. The significant increase in FA rates recorded has been associated with environmental and lifestyle changes that limit microbial exposure in early life and induce changes in gut microbiome composition. Gut microbiome is a diverse community of microbes that colonize the gastrointestinal tract (GIT) and perform beneficial functions for the host. This complex ecosystem interacts with the immune system and has a pivotal role in the development of oral tolerance to food antigens. Emerging evidence indicates that alterations of the gut microbiome (dysbiosis) in early life cause immune dysregulation and render the host susceptible to immune-mediated diseases later in life. 
  • 1.4K
  • 10 Nov 2022
Biography
Daryl Chapin
Daryl Muscott Chapin[1] (21 July 1906 – 19 January 1995) was an American physicist, best known for co-inventing solar cells in 1954 during his work at Bell Labs alongside Calvin S. Fuller and Gerald Pearson. For this, he was inducted into the National Inventors Hall of Fame in 2008. Chapin was born in Ellensburg, Washington (state) on 21 July 1906, although he spent his childhood in Salem,
  • 1.4K
  • 22 Nov 2022
Topic Review
Nanocrystalline Magnetic Semiconductors for Spintronics
Сhallenge for spintronics is to find new ways for the control of electronic phenomena and magnetic properties of solids at nanoscale. Some promising aspects are connected with developing new materials. The research highlights the areas devoted to the creation of new functional materials for spintronics based on magnetic semiconductors and demonstrates the technical possibilities of creating various devices, in particular, a maser, a p-n junction with a colossal magnetoresistance, a spin valve, a magnetic lens, modulators, spin wave amplifier, etc. A magnetic semiconductor is a magnetic material that, in terms of specific conductivity, occupies an intermediate position between a conductor and an insulator, and has a band gap comparable to ~kBT. Most known magnetic semiconductors (SC) are either oxides or chalcogenides (sulfides, selenides and tellurides) of 3d transition metals, rare earth 4f metals or a combination. Spintronics (spin electronics) studies spin current transfer (spin-polarized transport) in condensed media, including contact structures, heterostructures, superlattices and multilayers. Much attention is paid to the mechano-physical methods of obtaining of high-density transparent nanoceramics based on magnetic semiconductors. The potential possibility of using nanoceramics as an absorber of solar energy, as well as in modulators of electromagnetic radiation, is also presented. The THz magneto-optics in magnetic semiconductors is shown to be beneficial to the intensively developing fields of spintronics – ultrafast magnetooptics and magnetophotonics in magnetic semiconductors.
  • 1.4K
  • 20 Dec 2022
Topic Review
Klinefelter Syndrome and Testicular Sperm
Klinefelter syndrome (KS), caused by the presence of an extra X chromosome, is the most prevalent chromosomal sexual anomaly, with an estimated incidence of 1:500/1000 per male live birth (karyotype 47,XXY). High stature, tiny testicles, small penis, gynecomastia, feminine body proportions and hair, visceral obesity, and testicular failure are all symptoms of KS. Endocrine (osteoporosis, obesity, diabetes), musculoskeletal, cardiovascular, autoimmune disorders, cancer, neurocognitive disabilities, and infertility are also outcomes of KS.
  • 1.4K
  • 22 Mar 2023
Topic Review
Biopolymers Produced by Lactic Acid Bacteria
A severe and well-known threat to the environment, the non-biodegradability of plastics obliges different stakeholders to find legislative and technical solutions for producing valuable polymers which are biodegradable and also exhibit better characteristics for packaging products. Microorganisms are recognized as exciting sources for the production of biopolymers with applications in the food industry, package production, and several other fields. Ubiquitous organisms, lactic acid bacteria (LAB) are well studied for the production of exopolysaccharides (EPS), but much less as producers of polylactic acid (PLA) and polyhydroxyalkanoates (PHAs). Based on their good biodegradability feature, as well as the possibility to be obtained from cheap biomass, PLA and PHAs polymers currently receive increased attention from both research and industry.
  • 1.4K
  • 12 Apr 2023
Topic Review
Effects of Microbial Feed Additives on Ornamental Fish
Trade of ornamental fish has significantly increased. A rise in demand was observed, especially from top importing countries that contributed majorly to the growth of the market. Thus, there is a need to improve ornamental fish aquaculture, increasing the number of cultured species and limiting wild fish handling and transport stress losses. The use of microbial feed additives such as probiotics, prebiotics, and synbiotics, could help in improving the immune system and growth as well as increasing reproductive performance in captivity-bred species.
  • 1.4K
  • 29 May 2023
Topic Review
Astrocytic GABAergic Regulation in Alcohol Use
Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the central nervous system (CNS). Most GABAergic neurons synthesize GABA from glutamate and release it in the synaptic cleft in the CNS. However, astrocytes can also synthesize and release GABA, activating GABA receptors in the neighboring neurons in physiological and pathological conditions. As the primary homeostatic glial cells in the brain, astrocytes play a crucial role in regulating GABA homeostasis and synaptic neurotransmission. Accumulating evidence demonstrates that astrocytic GABA dysregulation is implicated in psychiatric disorders, including alcohol use disorder (AUD) and major depressive disorder (MDD), the most prevalent co-occurring psychiatric disorders. 
  • 1.4K
  • 20 Feb 2024
Topic Review
Mensa
Mensa is a faint constellation in the southern celestial hemisphere, first introduced by the French astronomer Nicolas Louis de Lacaille in the 18th century. It is named after the Table Mountain in South Africa.
  • 1.4K
  • 15 Mar 2024
Topic Review
April 17: Apollo 13 Returns Safely
Apollo 13 was a 1970 NASA Moon mission that turned into a survival crisis after an oxygen tank explosion. The crew, aided by Mission Control, used the Lunar Module as a lifeboat and improvised fixes to return safely. Though the Moon landing was canceled, the mission became a landmark example of problem-solving under pressure.
  • 1.4K
  • 17 Apr 2025
Topic Review
Chemical Derivatization in Flow Analysis
Chemical derivatization involves modification of the analyte for improving selectivity and/or sensitivity. It is particularly attractive in flow analysis in view of its highly reproducible reagent addition(s) and controlled timing. Then, measurements without attaining the steady state, kinetic discrimination, exploitation of unstable reagents and/or products, as well as strategies compliant with Green Analytical Chemistry, have been efficiently exploited. Flow-based chemical derivatization has been accomplished by different approaches, involving e.g. flow and manifold programming, solid-phase reagents, and strategies for sample insertion and reagent addition, as well as to increase sample residence time.
  • 1.4K
  • 08 Mar 2022
Topic Review
ERK/MAPK Pathway in Gastric Cancer
Gastric Cancer (GC) is turning out today to be one of the most important welfare issues for both Asian and European countries. Indeed, while the vast majority of the disease burden is located in China and in Pacific and East Asia, GC in European countries still account for about 100.000 deaths per year. With this review article, we aimed to focus the attention on one of the most complex cellular pathways involved in GC proliferation, invasion, migration and metastasis: the MAP Kinases. Such large kinases family is to date constantly studied, since their discovery more than 30 years ago, due to the important role that it plays in the regulation of physiological and pathological processes. Interactions with other cellular proteins as well as miRNAs and lncRNAs may modulate their expression influencing the cellular biological features. Here, we summarize the most important and recent studies involving MAPK in GC. At the same time, we need to underlie that, differently from cancers arising from other tissues, where MAPK pathways seems to be a gold target for anticancer therapies, GC seems to be unique in any aspect. Our aim is to review the current knowledge in MAPK pathways alterations leading to GC, including H. pylori MAPK-triggering to derail from gastric normal epithelium to GC and to encourage researches involved in MAPK signal transduction, that seems to definitely sustain GC development.
  • 1.4K
  • 28 Oct 2020
Topic Review
Sperm Cryopreservation Protocol
The storage of frozen sperm samples from birds in Germoplasm Banks could be a way out for the conservation of thousands of threatened species. The cryopreserved samples could be later used in reintroduction projects. This technology also allows for the selection of individuals of genetic interest and the exchange of samples between distant locations. Although the sperm cryopreservation is greatly developed in domestic species, in birds it is still in its infancy. The objective of this study was optimize the cryopreservation protocol in a bird of prey, peregrine falcon (Falco peregrinus) which could be used as a model for other threats. Thus, the freezing/thawing protocol and the type and concentration of cryoprotectant were evaluated.
  • 1.4K
  • 30 Oct 2020
Topic Review
Hydroa Vacciniforme, EBV, and Lymphoma
Hydroa vacciniforme (HV) is a rare form of photosensitivity disorder in children or adolescence and is frequently associated with Epstein–Barr virus (EBV) infection, whereas HV-like lymphoproliferative disorders (HVLPD) describe a spectrum of EBV-associated T-cell or natural killer (NK)-cell lymphoproliferations with HV-like cutaneous manifestations, including EBV-positive HV, atypical HV, and HV-like lymphoma. 
  • 1.4K
  • 23 Dec 2020
Topic Review
Genomic Research
Discovering the sequence of the human genome was a major goal of the Human Genome Project, completed in 2003. The next stage of genomic research will begin to derive meaningful knowledge from the DNA sequence. 
  • 1.4K
  • 24 Dec 2020
Topic Review
HNPP
Hereditary neuropathy with liability to pressure palsies is a disorder that affects peripheral nerves. These nerves connect the brain and spinal cord to muscles and sensory cells that detect touch, pain, and temperature. In people with this disorder, the peripheral nerves are unusually sensitive to pressure, such as the pressure that occurs when carrying heavy grocery bags, leaning on an elbow, or sitting without changing position, particularly with crossed legs. These activities would not normally cause sensation problems in people without the disorder.
  • 1.4K
  • 04 Jan 2021
Topic Review
Proton Transport Chain
Carboxylic acids dissociate in water to carboxylates (R-COO-) and oxonium (H+[H2O]n) ions. The Proton Transport Chain (PTC) hypothesis asserts that enzyme complexes bridge nascent acids and ensure water-free transfer of the intermediate substrate. The PTC hypothesis entails that the concentration of the transferred acid is mathematically infinite and an infinite concentration drives enzymatic reactions unidirectionally. In support of this, a number of enzymes, such as proton-linked monocarboxylate transporters (MCTs), lactate dehydrogenases (LDHs) or sodium/hydrogen exchangers have been experimentally determined to catalyse unidirectionally. In addition, enzyme complexes, such as the pyruvate dehydrogenase complex (PDHc), are also known to catalyse unidirectionally. Scientific concepts, such as the original Citric Acid Cycle proposed that acids are metabolized in a clockwise direction. The PTC hypothesis provides mechanisms, mathematics and law of nature for biological processes.
  • 1.4K
  • 26 Feb 2021
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