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Topic Review
Personal RF Safety Monitors
Electromagnetic field densitometers measure the exposure to electromagnetic radiation in certain ranges of the electromagnetic spectrum. This article concentrates on densitometers used in the telecommunication industry, which measure exposure to radio spectrum radiation. Other densitometers, like extremely low frequency densitometers which measure exposure to radiation from electric power lines, also exist. The major difference between a "Densitometer" and a "Dosimeter" is that a Dosimeter can measure the absorbed dose, which does not exist for RF Monitors. Monitors are also separated by "RF Monitors" that simply measure fields and "RF Personal Monitors" that are designed to function while mounted on the human body.
  • 1.4K
  • 14 Oct 2022
Topic Review
Archaeology of Wales
The Archaeology of Wales is the study of human occupation within the country of Wales, which has been occupied by modern humans since 225,000 BCE, with continuous occupation from 9,000 BCE. Analysis of the sites, artifacts and other archaeological data within Wales details its complex social landscape and evolution from Prehistoric times to the Industrial period. This study is undertaken by academic institutions, consultancies, charities as well as government organisations.
  • 1.4K
  • 17 Oct 2022
Topic Review
Umtsimba
A traditional Swazi wedding ceremony is called umtsimba (Template:IPA-ss), where the bride commits herself to her new family for the rest of her life. The ceremony is a celebration that includes members of both the bride's - and the groom's - natal village. There are stages to the wedding that stretch over a few days. Each stage is significant, comprising symbolic gestures that have been passed on from generation to generation. The first stage is the preparation of the bridal party before leaving their village. The second stage is the actual journey of the bridal party from their village to the groom's village. The third stage is the first day of the wedding ceremony that spans three days, and starts on the day the bridal party arrives at the grooms’ village. Thereafter the actual wedding ceremony takes place which is the fourth stage of the umtsimba. The fifth stage takes place the day after the wedding ceremony and is known as kuteka, which is the actual wedding. The final stage may take place the day after the wedding day, and is when the bride gives the groom's family gifts and is the first evening the bride spends with the groom. Although the traditional wedding ceremony has evolved in modern times, the details below are based on historic accounts of anthropologist Hilda Kuper and sociological research describing the tradition
  • 1.4K
  • 19 Oct 2022
Topic Review
Organogold Chemistry
Organogold chemistry is the study of compounds containing gold–carbon bonds. They are studied in academic research, but have not received widespread use otherwise. The dominant oxidation states for organogold compounds are I with coordination number 2 and a linear molecular geometry and III with CN = 4 and a square planar molecular geometry. The first organogold compound discovered was gold(I) carbide Au2C2, which was first prepared in 1900.
  • 1.4K
  • 04 Nov 2022
Biography
Farid Hafez
Farid Hafez (born 23 December 1981) is an Austrian political scientist, currently teaching and doing research at the Political Science Department at the University of Salzburg. Hafez was born in Ried im Innkreis, Austria on 23 December 1981. After moving to the capital city Vienna, taking his first degree in political science, he finished his studies and earned his PhD at University of Vienna
  • 1.4K
  • 12 Dec 2022
Topic Review
The Rhizobial Type 3 Secretion System
Rhizobia are soil bacteria that can establish a symbiotic association with legumes. As a result, plant nodules are formed on the roots of the host plants where rhizobia differentiate to bacteroids capable of fixing atmospheric nitrogen into ammonia. This ammonia is transferred to the plant in exchange of a carbon source and an appropriate environment for bacterial survival. This process is subjected to a tight regulation with several checkpoints to allow the progression of the infection or its restriction. The type 3 secretion system (T3SS) is a secretory system that injects proteins, called effectors (T3E), directly into the cytoplasm of the host cell, altering host pathways or suppressing host defense responses. The final effect of the different effectors can be neutral, beneficial or detrimental for symbiosis, depending on the host plants and the cocktail of effectors secreted. Whereas, in some cases, several T3SS effectors can induce the formation of nodules in the absence of Nod factors, in other cases the recognition of specific effectors by specific plant receptors can block nodulation. 
  • 1.4K
  • 15 Dec 2022
Topic Review
Coating Materials to Increase the Stability of Liposomes
Liposomes carry various compounds with applications in pharmaceutical, food, and cosmetic fields, and the administration route is especially parenteral, oral, or transdermal. Liposomes are used to preserve and release the internal components, thus maintaining the properties of the compounds, the stability and shelf life of the encapsulated products, and their functional benefits. The main problem in obtaining liposomes at the industrial level is their low stability due to fragile phospholipid membranes. To increase the stability of liposomes, phospholipid bilayers have been modified or different coating materials have been developed and studied, both for liposomes with applications in the pharmaceutical field and liposomes in the food field. In the cosmetic field, liposomes need no additional coating because the liposomal formulation is intended to have a fast penetration into the skin.
  • 1.4K
  • 04 May 2023
Topic Review
Bigels
Bigels have been mainly applied in the pharmaceutical sector for the controlled release of drugs or therapeutics. However, these systems, with their intricate structures, hold great promise for wider application in food products. Besides their classical role as carrier and target delivery vehicles for molecules of interest, bigels may also be valuable tools for building complex food structures. In the context of reducing or even eliminating undesirable (but often highly functional) food components, current strategies often critically affect food structure and palatability. The production of solid fat systems that are trans-fat-free and have high levels of unsaturated fatty acids is one of the challenges the food industry currently faces. 
  • 1.4K
  • 13 Nov 2023
Topic Review
Nucleolar and Ribosomal Dysfunction
Ageing is a complex and unavoidable process that can be defined as the functional decline after a period of maturity. In this respect, maturity is understood as the endpoint of development and the condition of maximal functional performance capability.  The nucleolus organizes around the sites of transcription by RNA polymerase I (RNA Pol I). rDNA transcription by this enzyme is the key step of ribosome biogenesis and most of the assembly and maturation processes of the ribosome occur co-transcriptionally. Therefore, disturbances in rRNA transcription and processing translate to ribosomal malfunction. Nucleolar malfunction has recently been described in the classical progeria of childhood, Hutchinson–Gilford syndrome (HGPS), which is characterized by severe signs of premature aging, including atherosclerosis, alopecia, and osteoporosis. A deregulated ribosomal biogenesis with enlarged nucleoli is not only characteristic for HGPS patients, but it is also found in the fibroblasts of “normal” aging individuals. Cockayne syndrome (CS) is also characterized by signs of premature aging, including the loss of subcutaneous fat, alopecia, and cataracts. It has been shown that all genes in which a mutation causes CS, are involved in rDNA transcription by RNA Pol I. 
  • 1.4K
  • 27 Apr 2022
Topic Review
Electrofermentation of Lactic Acid Bacteria
Microbial electrosynthesis is the process of supplying electrons to microorganisms to reduce CO2 and yield industrially relevant products. Such systems are limited by their requirement for high currents, resulting in challenges to cell survival. Electrofermentation is an electron-efficient form of microbial electrosynthesis in which a small cathodic or anodic current is provided to a culture to alter the oxidation–reduction potential of the medium and, in turn, alter microbial metabolism. This approach has been successfully utilised to increase yields of diverse products including biogas, butanediol and lactate. Biomass conversion to lactate is frequently facilitated by ensiling plant biomass with homofermentative lactic acid bacteria. Although most commonly used as a preservative in ensiled animal feed, lactate has diverse industrial applications as a precursor for the production of probiotics, biofuels, bioplastics and platform chemicals. Lactate yields by lactic acid bacteria (LAB) are constrained by a number of redox limitations which must be overcome while maintaining profitability and sustainability. 
  • 1.4K
  • 02 Dec 2022
Topic Review
Anticancer Potential of Furanocoumarins
       Cancer is one of the most extreme medical conditions in both developing and developed countries around the world, causing millions of deaths each year. Chemotherapy and/or radiotherapy are key for treatment approaches, but both have numerous adverse health effects. Furthermore, the resistance of cancerous cells to anticancer medication leads to treatment failure. The rising burden of cancer overall requires novel efficacious treatment modalities. Natural medications offer feasible alternative options against malignancy in contrast to western medication.        This review highlights the potential for furanocoumarins to be clinically beneficial in cancer, particularly given their specificity to tumor cells (while sparing normal cells). In vitro investigations have shown that furanocoumarins affect a range of cellular mechanisms, such as apoptosis, autophagy, and cell cycle arrest. ER stress induction mainly caused by NF-κB inactivation, PI3K/Akt inhibition, and p53 modulation. Furanocoumarins are also effective in different MDR cancers that are the main cause of anticancer therapeutics failure.       Compounds in this class have also have been shown to positively synergize with commonly used anticancer drugs. The fast absorption of furanocoumarins from food into the human bloodstream is also noteworthy.  Furanocoumarins, by inhibiting CYP P450 3A4, not only have anticancer properties but also when co-administered with a low bioavailability anticancer compound can increase oral bioavailability. To date, most focus has been on in vitro studies, making it hard to reach solid conclusions on the efficacy of furanocoumarins in vivo.       Nonetheless, studies aimed at characterizing furanocoumarin’s efficacy in vivo as well as clinical studies are encouraging, supporting the need for future studies to better characterize furanocoumarin’s potential as efficacious anticancer treatment modalities.
  • 1.4K
  • 27 Aug 2020
Topic Review
Fabry Nephropathy
Fabry disease (FD; OMIM#301500) is an X-linked lysosomal storage disorder associated with inherited or de novo disease causing variants in the α-galactosidase A gene (GLA; OMIM*300644). Reduced or even absent α-galactosidase A (α-Gal A; EC 3.2.1.22) activity leads to accumulation of glycosphingolipids with terminal α-D-galactosyl residues, especially globotriaosylceramide (Gb3) and globotriaosylsphingosine (lyso-Gb3) in plasma, urine and different organ systems, mainly cardiac, renal, endothelial and neuronal. The major physiological source of Gb3 is globoside, a glycolipid of erythrocytes and cells membranes found in different tissues. Kidneys are very frequently affected in patients with Fabry disease regardless of gender. Most important manifestations of Fabry nephropathy are proteinuria and slowly progressive chronic kidney disease, which can in some cases lead to end stage renal disease.
  • 1.4K
  • 27 Sep 2020
Topic Review
Insights from Circular Economy Literature
The circular economy (CE) has become one of the prominent topics in both natural science and management literature over the last few decades. CE is a dual-loop regenerative system that focuses on the effective and efficient utilization of resources in the ecosystem, which is beneficial to environmental and economic performance optimization. Dual CE initiatives allow firms to increased resource eco-efficiency, as well as resource effectiveness. 
  • 1.4K
  • 20 Feb 2021
Topic Review
Cardiac Development
Cardiac development is a complex developmental process that is initiated soon after gastrulation, as two sets of precardiac mesodermal precursors are symmetrically located and subsequently fused at the embryonic midline forming the cardiac straight tube. Thereafter, the cardiac straight tube invariably bends to the right, configuring the first sign of morphological left–right asymmetry and soon thereafter the atrial and ventricular chambers are formed, expanded and progressively septated. As a consequence of all these morphogenetic processes, the fetal heart acquired a four-chambered structure having distinct inlet and outlet connections and a specialized conduction system capable of directing the electrical impulse within the fully formed heart.
  • 1.4K
  • 26 Feb 2021
Topic Review
Serotonin-Norepinephrine Reuptake Inhibitors
Serotonin-norepinephrine reuptake inhibitors (SNRIs) are among the most commonly prescribed medications in the United States annually. As their name suggests, the principle mechanism of action is the inhibition of presynaptic neuronal uptake of 5-HT (serotonin) and norepinephrine following release from the synaptic cleft.
  • 1.4K
  • 28 Oct 2021
Topic Review
Influence of Cold Spray Parameters on Bonding Mechanisms
The cold spray process is governed by the impact of high velocity feedstock particles onto a substrate without melting. Hence, the bulk material properties are retained. However, it is challenging to achieve good adhesion strength. The adhesion strength depends on factors such as the cold spray process parameters, substrate conditions, coating/substrate interactions at the interface and feedstock material properties. This entry examines fundamental studies concerning the adhesion mechanisms of cold spray technology and considers the effect of cold spray input parameters such as temperature, stand-off-distance, pressure, process gas, spray angle, and traverse speed of the cold spray torch on the bonding mechanism and adhesion strength. Furthermore, the effects of substrate conditions such as temperature, hardness, roughness and material on the adhesion mechanism are highlighted. The effect of feedstock properties, such as feed rate, shape and size are summarized. Understanding the effect of these parameters is necessary to obtain the optimal input parameters that enable the best interfacial properties for a range of coating/substrate material combinations. It is expected that feedstock of spherical morphology and small particle size (<15 μm) provides optimal interfacial properties when deposited onto a mirror-finished substrate surface using high pressure cold spray. Deep insights into each parameter exposes the uncovered potential of cold spray as an additive manufacturing method.
  • 1.4K
  • 11 Jan 2022
Topic Review
Monitoring of Six-Minute Walk Test
In the pandemic time, the monitoring of the progression of some diseases is affected and rehabilitation is more complicated. Remote monitoring may help solve this problem using mobile devices that embed low-cost sensors, which can help measure different physical parameters. Many tests can be applied remotely, one of which is the six-minute walk test (6MWT). The 6MWT is a sub-maximal exercise test that assesses aerobic capacity and endurance, allowing early detection of emerging medical conditions with changes. 
  • 1.4K
  • 02 Feb 2022
Topic Review
Ecological Footprint for the Algerian Fisheries Management
According to the estimated ecological footprint (EF) of fishery production (EFf), Algiers fishing is in the status of ecological surplus, as the demand for fisheries production averages 15,338.49 gha compared to more than 108 thousand gha of biologically productive fishing area. In addition to this overall output, this metric indicates each species’ primary production requirement (PPR), which could help to restructure the fishing effort based on the stock’s condition. For the energy component, the fuel consumption and greenhouse gas (GHG) emissions expressed in metric tons of CO2 were used to estimate the required area for carbon sequestration, valued roughly at 500 gha. The latter is a reference state and remains approximate because it was derived from unofficial data provided by the fishers.
  • 1.4K
  • 31 Jan 2022
Topic Review
3D Printed Nonlinear Musculoskeletal Actuator
A nature-inspired musculoskeletal-actuator system is developed using 3d printing for robotic applications. The actuator resembles the rigid segments and the soft-rigid interaction architecture found in limbless vertebrates such as snakes. The rigid segments provide an increase in the range of motion while maintaining structural durability and stability. The soft-rigid interactions provided a remarkable increase in energy transmission and storage, which enhanced the reliability of the musculoskeletal-actuator. Additionally, passive structural stiffness and damping control are achieved. Similar to a muscular system, our musculoskeletal-actuator is capable of increasing its stiffness and damping up to 100% and 60%, respectively, upon load lifting.
  • 1.4K
  • 28 Mar 2022
Topic Review
Decentralized Multi-Robot Collision Avoidance
When deploying a multi-robot system, it is ensured that the hardware parts do not collide with each other or the surroundings, especially in symmetric environments. Two types of methods are used for collision avoidance: centralized and decentralized. The decentralized approach has mainly been used in recent times, as it is computationally less expensive.
  • 1.4K
  • 19 Apr 2022
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