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Topic Review
Machine Learning for RC monitoring
The reciprocating compressor (RC) is a key piece of equipment in petroleum and chemical industries. If the RC does not operate in the rated efficiency, it will lead to great economic loss to the company. Sometimes RCs are used to compress inflammable and explosive gases working under high pressures and temperatures, such as hydrogen, ethylene, and natural gas, which would threat human life once the machine malfunctions. Furthermore, due to the intricate structure of the compressor, a large amount of wearing parts, and the complicated interactional relationship between moving parts of the compressor, it is essential to monitor the compressor operating condition and detect failures of RCs accurately and in a timely manner. Operating condition detection and fault diagnosis are very important for reliable operation of reciprocating compressors. Machine learning is one of the most powerful tools in this field.
  • 1.5K
  • 06 Jun 2021
Topic Review
Vitamin E in Neuro-Nutrition
Vitamin E was first discovered by the American endocrinologist and anatomist Herbert. M. Evans, together with his assistant Katherine S. Bishop. The isolated substance, later termed vitamin E, describes a group of compounds consisting of four tocopherol (TP)- and four tocotrienol (TT)-derivatives.
  • 1.5K
  • 27 Oct 2021
Topic Review
Development of SARS-CoV-2 Variants
A novel coronavirus (SARS-CoV-2) emerged towards the end of 2019 that caused a severe respiratory disease in humans called COVID-19. It led to a pandemic with a high rate of morbidity and mortality that is ongoing and threatening humankind. Most of the mutations occurring in SARS-CoV-2 are synonymous or deleterious, but a few of them produce improved viral functions. The first known mutation associated with higher transmissibility, D614G, was detected in early 2020. Since then, the virus has evolved; new mutations have occurred, and many variants have been described. Depending on the genes affected and the location of the mutations, they could provide altered infectivity, transmissibility, or immune escape. To date, mutations that cause variations in the SARS-CoV-2 spike protein have been among the most studied because of the protein’s role in the initial virus–cell contact and because it is the most variable region in the virus genome. Some concerning mutations associated with an impact on viral fitness have been described in the Spike protein, such as D614G, N501Y, E484K, K417N/T, L452R, and P681R, among others. To understand the impact of the infectivity and antigenicity of the virus, the mutation landscape of SARS-CoV-2 has been under constant global scrutiny. The virus variants are defined according to their origin, their genetic profile (some characteristic mutations prevalent in the lineage), and the severity of the disease they produce, which determines the level of concern. If they increase fitness, new variants can outcompete others in the population. The Alpha variant was more transmissible than previous versions and quickly spread globally. The Beta and Gamma variants accumulated mutations that partially escape the immune defenses and affect the effectiveness of vaccines. Nowadays, the Delta variant, identified around March 2021, has spread and displaced the other variants, becoming the most concerning of all lineages that have emerged. The Delta variant has a particular genetic profile, bearing unique mutations, such as T478K in the spike protein and M203R in the nucleocapsid. This entry summarizes the current knowledge of the different mutations that have appeared in SARS-CoV-2, mainly on the spike protein. It analyzes their impact on the protein function and, subsequently, on the level of concern of different variants and their importance in the ongoing pandemic. 
  • 1.5K
  • 28 Dec 2021
Topic Review
Age-Dependent Decline of NAD+—Universal Truth or Confounded Consensus?
Nicotinamide adenine dinucleotide (NAD+) is an essential molecule involved in various metabolic reactions, acting as an electron donor in the electron transport chain and as a co-factor for NAD+-dependent enzymes. Despite systematic claims of overall decline in NAD+ levels with aging in multiple species, including humans, the evidence to support such claims is very limited and often restricted to a single tissue or cell type. The literature on the topic has been reviewed and it is found that there is a need for much larger, preferably longitudinal, studies to assess how NAD+ levels develop with aging.
  • 1.5K
  • 11 Jan 2022
Topic Review
Tetranychus urticae in Northern Africa
In North Africa, Tetranychus urticae Koch, 1836 represents one of the most destructive generalists among mite herbivores. Unfortunately, it is a source of important annual casualties in crop production. It is a phytophagous mite that can feed on hundreds of host plants and produces significant damage. The control of Tetranychus urticae in North Africa has been principally based on acaricide sprays. However, new alternative methods have shown effective results, such as artificial ultraviolet-B, natural enemies, and the introduction of new genetic methods.
  • 1.5K
  • 30 Mar 2022
Topic Review
Gut Microbiota and Sex Hormones
Gut microbiota (GM) is the set of microbe strains colonizing the intestinal tract. Through its genetic heritage, known as the gut microbiome, this complex ecosystem generates bioactive metabolites that impact various physiological processes, far beyond food digestion. Able to communicate with distal districts through multiple pathways, GM is therefore considered the largest endocrine organ of the body and one of the major determinants of humans’ health from infancy through adulthood. Indeed, while a balanced GM facilitates beneficial effects including digestion of macronutrients, synthesis of some vitamins, maintenance of immune homeostasis, and protection against pathogens, detrimental changes in GM composition lead to adverse remodeling of the host phenotype, which predispose to several pathological conditions, such as insulin resistance, atherosclerosis, obesity, and associated disorders, ultimately leading to cardiovascular disease (CVD). Dietary habit and sex hormones (SH) are considered major regulators of the GM variability (6, 7).
  • 1.5K
  • 07 Jul 2022
Topic Review
Sugar
Sugar is a free and open-source desktop environment designed for interactive learning by children. Copyright by SugarLabs. Developed as part of the One Laptop per Child (OLPC) project, Sugar was the default interface on OLPC XO-1 laptop computers. The OLPC XO-1.5 and later provided the option of either the Gnome or Sugar interfaces. Sugar is available as a Live CD, as Live USB, and a package installable through several Linux distributions. It can run in a Linux virtual machine under Windows and Mac OS. Unlike most other desktop environments, Sugar does not use the "desktop", "folder" and "window" metaphors. Instead, Sugar's default full-screen activities require users to focus on only one program at a time. Sugar implements a journal which automatically saves the user's running program session and allows them to later use an interface to pull up their past works by date, an activity used, or file type.
  • 1.5K
  • 08 Nov 2022
Biography
Oliver Letwin
Sir Oliver Letwin, FRSA (born 19 May 1956[1]) is a British Conservative politician. He has served as Member of Parliament for West Dorset since 1997. He was Chancellor of the Duchy of Lancaster from 2014 to 2016. Following the 2015 general election, Letwin was given overall responsibility for the Cabinet Office and became a full member of the Cabinet in the Conservative government. Previously,
  • 1.5K
  • 28 Nov 2022
Topic Review
Nokia N73
The Nokia N73 is a smartphone announced by Nokia on 25 April 2006, as part of the Nseries and started shipping on 24 July. The N73 succeeded the N70 and packed in numerous multimedia features. It features a 3.2 megapixel autofocus camera, a front camera, a then-large 2.4 inch display, and stereo speakers, all in a relatively slim and pocketable size and form. It runs on Symbian v9.1 (S60 3rd Edition). It became one of the top selling Nseries devices during 2006 and 2007, and its high popularity helped Nokia's sales of 'multimedia' phones grow 28% year-on-year in Q3 2007 (according to Nokia the other top selling from the line were the N70 and N95).
  • 1.5K
  • 01 Dec 2022
Topic Review
Changes of Endothelial Glycocalyx in Cardiac Surgery
Cardiac surgery is one of the highest-risk procedures, usually involving cardiopulmonary bypass and commonly inducing endothelial injury that contributes to the development of perioperative and postoperative organ dysfunction. Substantial scientific efforts are being made to unravel the complex interaction of biomolecules involved in endothelial dysfunction to find new therapeutic targets and biomarkers and to develop therapeutic strategies to protect and restore the endothelium. 
  • 1.5K
  • 17 May 2023
Topic Review
Digital Banking Implementation Indicators in Industry 4.0
Extensive technological changes brought about by Industry 4.0 have changed the behaviors and attitudes of customers and created new needs for them. The digital transformation of banking encompasses a wide range of services, such as document digitization, electronic signatures for transactions, e-learning, teleconferencing, online trading platforms, digital stores, e-statements, and mobile payments. Adopting new business models through the digital transformation of banking operations is the most appropriate approach for banking institutions in today’s economic environment.
  • 1.5K
  • 31 May 2023
Topic Review
Mechanism of Saponins in Treating Alzheimer’s Disease
Drug development for Alzheimer’s disease, the leading cause of dementia, has been a long-standing challenge. Saponins, which are steroid or triterpenoid glycosides with various pharmacological activities, have displayed therapeutic potential in treating Alzheimer’s disease. 
  • 1.5K
  • 31 Jul 2023
Topic Review
Composition of Red Fruit Juices
Red fruit juices are appreciated for almost all consumers due to their flavor and intense red color. Studies have also shown that their phytochemical composition, associated with their antioxidant activity, is protective against many chronic diseases.
  • 1.5K
  • 13 Sep 2023
Topic Review
Uncoupling Proteins for Neurodegenerative Diseases
Most of the major retinal degenerative diseases are associated with significant levels of oxidative stress. One of the major sources contributing to the overall level of stress is the reactive oxygen species (ROS) generated by mitochondria. The driving force for ROS production is the proton gradient across the inner mitochondrial membrane. This gradient can be modulated by members of the uncoupling protein family, particularly the widely expressed UCP2. The overexpression and knockout studies of UCP2 in mice have established the ability of this protein to provide neuroprotection in a number of animal models of neurological disease, including retinal diseases. The expression and activity of UCP2 are controlled at the transcriptional, translational and post-translational levels, making it an ideal candidate for therapeutic intervention. 
  • 1.5K
  • 30 Jun 2022
Topic Review
Dendrite-Free Sodium Metal Anodes
Nature-abundant sodium metal is regarded as ideal anode material for advanced batteries due to its high specific capacity of 1166 mAh g−1 and low redox potential of −2.71 V. The uncontrollable dendritic Na formation and low coulombic efficiency remain major obstacles to its application. Notably, the unstable and inhomogeneous solid electrolyte interphase (SEI) is recognized to be the root cause.
  • 1.5K
  • 06 Jul 2023
Topic Review
Gangliosides in Vascular
Vascular diseases, such as myocardial infarction and cerebral infarction, are most commonly caused by atherosclerosis, one of the leading causes of death worldwide. Several types of cells, such as vascular (endothelial cell), vascular-associated (smooth muscle cell and fibroblast) and inflammatory cells, are involved in plaque formation, plaque rupture and thrombus formation, which result in atherosclerosis. Gangliosides, a group of glycosphingolipids, are expressed on the surface of vascular, vascular-associated and inflammatory cells, where they play functional roles. Here we introduce gangliosides expressed on those cells and their relevance to vascular diseases.
  • 1.5K
  • 23 Oct 2020
Topic Review
Pedestrian–Vehicle Interaction at Unsignalized Crosswalks
A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), to generate a document that supports the development of future research, compiling the various studies focused on the analysis of the pedestrian-vehicle interaction at unsignalized crosswalks. Firstly, 381 studies were identified by applying the search protocol in the database sources; however, only nine studies were included in this review because most of the studies are not focused on this type of crosswalks or have not considered the micro-simulation perspective. For each study, an analysis of the used methodology for data collection was carried out, in addition to what type of model it was applied, including the variables that represent the PVI (Pedestrian-Vehicle Interaction). The outcomes obtained by this systematic review show that although the video camera observation technique is the most used, it is possible to complement them with other tools to add specific field information. Additionally, variables such as the adjacent yields, speed variables vehicles, pedestrian attitude, and the number of pedestrians waiting at the crossing were those most used in the cellular automata model or micro-simulation, which are the commonly developed models to simulate this interaction.
  • 1.5K
  • 25 Apr 2020
Topic Review
Elovl4 genes in Sparus aurata
Very long-chain (˃C24) fatty acids (VLC-FA) play critical roles during early development of vertebrates, since these compounds are accumulated in the rapidly forming neural tissues, ensuring their normal function. However, despite their putative importance, the study of VLC-FA in fish is scarce. Biosynthesis of VLC-FA is carried out by the so-called elongation of very long-chain fatty acid 4 (Elovl4) proteins and, consequently, the complement and function of these enzymes determine the capacity that a given species has for satisfying the physiological demands for VLC-FA, especially during its early development. The present study aimed to characterize elovl4 genes from the marine teleosts Sparus aurata and Solea senegalensis, and determine the function of the corresponding encoded proteins. Moreover, the tissue expression pattern of elovl4 genes was determined. The results confirmed that both fish species possess two distinct Elovl4 proteins termed as Elovl4a and Elovl4b based on their homology to the zebrafish orthologs. Functional assays in yeast denoted that both Elovl4a and Elovl4b from both species had the capability to elongate C20-24 fatty acid precursors to VLC-FA products. However, Elovl4b appeared to have a higher activity than Elovl4a elongating all the polyunsaturated fatty acid substrates assayed to longer chain polyunsaturated products, especially on the n-3 series. Gene expression results indicated that, although elovl4 transcripts were detected in most tissues analyzed, elovl4 genes were more strongly expressed in both species neural tissues such as brain and eyes, which showed the highest expression levels of elovl4a and elovl4b, respectively. These results are consistent with the functions of Elovl4 from other vertebrates. Importantly, these findings contribute to a better understanding of the VLC-FA biosynthetic pathway in marine teleosts, highlighting the crucial role that Elovl4 products carry out for the correct development and maintenance of neurophysiologic functions during early stages of the fish development.
  • 1.5K
  • 28 Oct 2020
Topic Review
Mesoporous Silica Nanoparticles therapy potential
Nanoparticles have become a powerful tool in oncology not only as carrier of the highly toxic chemotherapeutic drugs but also as imaging contrast agents that provide valuable information about the state of the disease and its progression. The enhanced permeation and retention effect for loaded nanocarriers in tumors allow substantial improvement of selectivity and safety of anticancer nanomedicines. Additionally, the possibility to design stimuli-responsive nanocarriers able to release their payload in response to specific stimuli provide an excellent control on the administered dosage.
  • 1.5K
  • 15 Oct 2020
Topic Review
Negative Emotions in Career Decision-Making
Within the context of career counseling, clients often regard negatives feelings toward vocational options as inconsequential. Regrettably, by doing so, they discount the significance of the affect and overlook an important source of information. In the following study, Puffer and Pence investigated college students' negative emotional reactions to self- or computer reported occupations and the rationales for the selection of the negative affect. Their findings reveal how negative emotionality can be adaptive and feasibly assist career decision-makers.   
  • 1.5K
  • 02 Dec 2020
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