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Topic Review
Molecular Iodine-Catalyzed Reactions
Department of Mathematics and Natural Sciences, College of Sciences and Human Studies, Deanship of Research, Prince Mohammad Bin Fahd University, Al Khobar 31952, KSA; Email: bimalbanik10@gmail.com; bbanik@pmu.edu.sa In continuation of our research on the synthesis of diverse organic molecules, we report here molecular iodine-catalyzed diverse synthetic processes. These methods are efficient and produce products in high yield. The success of molecular iodine-catalyzed reactions depends on the release of hydroiodic acid in the reaction media.
  • 2.1K
  • 01 Jun 2020
Topic Review
Calcium Carbonate
Technologies for the management of various types of waste and the production of useful products from them are currently widely studied. Both carbon dioxide and calcium-rich waste from various production processes are problematic wastes that can be used to produce calcium carbonate. Therefore, the purpose of this paper is to provide an overview about the state of the development of processes that use these two wastes to obtain a valuable CaCO3 powder.
  • 2.1K
  • 15 Dec 2020
Topic Review
Aldose Reductase
Aldose reductase (AR) is a member of the reduced nicotinamide adenosine dinucleotide phosphate (NADPH)-dependent aldo-keto reductase superfamily. It is also the rate-limiting enzyme of the polyol pathway, catalyzing the conversion of glucose to sorbitol, which is subsequently converted to fructose by sorbitol dehydrogenase. AR is highly expressed by Schwann cells in the peripheral nervous system (PNS). The excess glucose flux through AR of the polyol pathway under hyperglycemic conditions has been suggested to play a critical role in the development and progression of diabetic peripheral neuropathy (DPN).
  • 2.1K
  • 09 Feb 2021
Topic Review
Tryptophan Metabolism
Tryptophan metabolism, via the kynurenine (Kyn) pathway, and microbial transformation of tryptophan to indolic compounds are fundamental for host health; both of which are altered in colon carcinogenesis. 
  • 2.1K
  • 07 May 2021
Topic Review
Green Finance
The concept of green finance, also known as green investments, is widely employed in academia and business, and have a variety of meanings. Green finance (GF) is a developing concept that lacks a clear and universal definition. However, the goal of GF is to balance the advancement of monetary events, environmental stability, and ecological protection to accomplish long-term development. 
  • 2.1K
  • 09 Oct 2021
Topic Review
Curcumin as a Potential Neuroprotective Agent
Parkinson’s disease (PD) is a slowly progressive multisystem disorder affecting dopaminergic neurons of the substantia nigra pars compacta (SNpc), which is characterized by a decrease of dopamine (DA) in their striatal terminals. A crucial unmet demand in the management of Parkinson’s disease is the discovery of new approaches that could slow down, stop, or reverse the process of neurodegeneration. Novel potential treatments involving natural substances with neuroprotective activities are being developed. Curcumin is a polyphenolic compound isolated from the rhizomes of Curcuma longa (turmeric), and is considered a promising therapeutic and nutraceutical agent for the treatment of PD. However, molecular and cellular mechanisms that mediate the pharmacological actions of curcumin remain largely unknown. Stimulation of nicotinic receptors and, more precisely, selective α7 nicotinic acetylcholine receptors (α7-nAChR), have been found to play a major modulatory role in the immune system via the “cholinergic anti-inflammatory pathway”. Recently, α7-nAChR has been proposed to be a potential therapeutic approach in PD. In this review, the detailed mechanisms of the neuroprotective activities of curcumin as a potential therapeutic agent to help Parkinson’s patients are being discussed and elaborated on in detail.
  • 2.1K
  • 12 Nov 2021
Topic Review
Felicia (Genus)
Felicia is a genus of small shrubs, perennial or annual herbaceous plants, with 85 known species, that is assigned to the daisy family (Compositae or Asteraceae). Like in almost all Asteraceae, the individual flowers are 5-merous, small and clustered in typical heads, and which are surrounded by an involucre of, in this case between two and four whorls of, bracts. In Felicia, the centre of the head is taken by yellow, seldomly whitish or blackish blue disc florets, and is almost always surrounded by one single whorl of mostly purple, sometimes blue, pink, white or yellow ligulate florets and rarely ligulate florets are absent. These florets sit on a common base (or receptacle) and are not individually subtended by a bract (or palea). Most species occur in the Cape Floristic Region, which is most probably the area where the genus originates and had most of its development. Some species can be found in the eastern half of Africa up to Sudan and the south-western Arabian peninsula, while on the west coast species can be found from the Cape to Angola and one species having outposts on the Cameroon-Nigeria border and central Nigeria. Some species of Felicia are cultivated as ornamentals and several hybrids have been developed for that purpose.
  • 2.1K
  • 21 Oct 2022
Topic Review
Large Synoptic Survey Telescope
The Large Synoptic Survey Telescope (LSST) is a wide-field survey reflecting telescope with an 8.4-meter primary mirror, currently under construction, that will photograph the entire available sky every few nights. The word synoptic is derived from the Greek words σύν (syn "together") and ὄψις (opsis "view"), and describes observations that give a broad view of a subject at a particular time. The telescope uses a novel 3-mirror design, a variant of three-mirror anastigmat, which allows a compact telescope to deliver sharp images over a very wide 3.5-degree diameter field of view. Images will be recorded by a 3.2-gigapixel CCD imaging camera, the largest digital camera ever constructed. The telescope is located on the El Peñón peak of Cerro Pachón, a 2,682-meter-high mountain in Coquimbo Region, in northern Chile , alongside the existing Gemini South and Southern Astrophysical Research Telescopes. The LSST Base Facility is located about 100 kilometres (62 mi) away by road, in the town of La Serena. The LSST was proposed in 2001, and construction of the mirror began (with private funds) in 2007. LSST then became the top-ranked large ground-based project in the 2010 Astrophysics Decadal Survey, and the project officially began construction 1 August 2014 when the National Science Foundation (NSF) authorized the FY2014 portion ($27.5 million) of its construction budget. The ceremonial laying of the first stone was performed on 14 April 2015. Site construction began on April 14, 2015, with engineering first light anticipated in 2019, science first light in 2021, and full operations for a ten-year survey commencing in January 2022. LSST, unlike almost all previous large astronomical observatories, has committed to making all data public as soon as it is taken. In their words "By providing immediate public access to all the data it obtains, it will provide everyone, the professional and the “just curious” alike, a deep and frequent window on the entire sky."
  • 2.1K
  • 10 Nov 2022
Topic Review
Chia Seeds
Chia (Salvia hispanica L.) is a small seed that comes from an annual herbaceous plant, Salvia hispanica L. Chia seeds contain healthy ω-3 fatty acids, polyunsaturated fatty acids, dietary fiber, proteins, vitamins, and some minerals. Besides this, the seeds are an excellent source of polyphenols and antioxidants, such as caffeic acid, rosmarinic acid, myricetin, quercetin, and others.
  • 2.1K
  • 24 Feb 2022
Topic Review
Photoautotrophic Euendoliths
Photoautotrophic euendoliths, including cyanobacteria, and red and green microalgae, are part of the endolithic community. The term ‘endolith’ refers to a morphologically and physiologically heterogenous group of microorganisms living within a rock or other stony matter, such as coral skeletons or animal shells, and more specifically, to organisms that actively bore into relatively soluble substrates, such as phosphate and carbonate substrates. Euendoliths are ubiquitous, as they can be found in almost every environment, geographical location, or depth, where the appropriate substratum (e.g., relatively soluble carbonate and phosphate substrates) is available and the requirements for photosynthesis are met. The most diverse and abundant modern euendolithic communities can be found in the marine environment. Euendoliths, as microorganisms infesting inanimate substrates, were first thought to be ecologically irrelevant. Numerous studies have subsequently shown that euendoliths can colonize living marine calcifying organisms, such as coral skeletons and bivalve shells, causing both sub-lethal and lethal damage. Moreover, under suitable environmental conditions, their presence can have surprising benefits for the host. Thus, infestation by photoautotrophic euendoliths has significant consequences for calcifying organisms that are of particular importance in the case of ecosystems underpinned by calcifying ecosystem engineers.
  • 2.1K
  • 17 Oct 2022
Topic Review
Bioreactors for Manufacturing of Adoptive Cell Immunotherapies
Harnessing the human immune system as a foundation for therapeutic technologies capable of recognizing and killing tumor cells has been the central objective of anti-cancer immunotherapy. There has been an increasing interest in improving the effectiveness and accessibility of this technology to make it widely applicable for adoptive cell therapies (ACTs) such as chimeric antigen receptor T (CAR-T) cells, tumor infiltrating lymphocytes (TILs), dendritic cells (DCs), natural killer (NK) cells, and many other. Automated, scalable, cost-effective, and GMP (good manufacture practice)-compliant bioreactors for production of ACTs are urgently needed. The existing and most advanced systems for ACT manufacturing, including cell culture bags, G-Rex flasks etc.
  • 2.1K
  • 29 Dec 2022
Topic Review
Crumb Rubber
The crumb rubber (CR) recycled from waste tyres could be a viable alternative in achieving green pavements that offer exciting new markets to global investors. Adding CR into flexible pavements enhances their performance and ensures environmental sustainability.
  • 2.1K
  • 08 Dec 2023
Topic Review
Retinal Organization
The retinal arhitecture is similar across all vertebrates despite the morphological and functional peculiarities. The retina is composed of two main parts: the single-layred retinal pigment epithelium and the multilayred neuroretina which includes a number of neuronal and glial cell types. Homeobox genes from different classes are accepted as critical for eye field specification and retinal cells type differentiation by a broad array of loss- or gain-of-function models. Among these genes are some that are known to cause inherited retinal diseases (IRDs) that disturb the formation, function, and survival of rod and cone photoreceptors, ganglion cells, or retinal pigment epithelial cells [4,6–8]. The advances in the field of genetics and high-throughput next-generation sequencing and cell technologies allow for deepening of knowledge of the genetic basis of inherited retinal diseases (IRDs), as well as improve their diagnostics and therapy.
  • 2.1K
  • 22 Sep 2021
Topic Review
Density Profile of Liquid-Metal-Vapor Interface
Several metals and many alloys are in liquid form around room temperature, e.g., mercury (Hg, −38.8 °C), francium (Fr, 8.0 °C), cesium (Sc, 28.5 °C), gallium (Ga, 29.8 °C), the eutectic mercury-based alloys, and the eutectic gallium-based alloys. If eutectic, liquid metal alloys can be in liquid form that has been used in practical applications, replacing mercury. Liquid metals have high thermal and electric conductivity and have been used to conduct heat and electricity between non-metallic and metallic surfaces. They have also been used as thermal interface materials between coolers and processors. Concerning these metals, our understanding of the liquid-vapor interface is critical for proper applications. This entry summarizes the basic features of the density distribution of liquid metal-vapor interface, which are advanced based on pseudo-potential representation and numerical simulation at the University of Chicago.
  • 2.1K
  • 30 Dec 2020
Topic Review
Battery-Driven Fast Marine Vehicles
Entry of the design and technological challenges of zero emission, battery driven fast marine vehicles. Whereas slow and medium speed all electrical ships have been successfully introduced, it remains to prove that fast battery driven ships are feasible. The entry addresses the key design and technological issues, assesses the present state of the art and of the associated technology and concludes on the way ahead.
  • 2.1K
  • 23 Nov 2020
Topic Review
Preeclampsia
Preeclampsia (PE) is a common obstetric disease characterized by hypertension, proteinuria, and multi-system dysfunction. It endangers both maternal and fetal health. Although hemostasis is critical for preventing bleeding complications during pregnancy, delivery, and post-partum, PE patients often develop a severe prothrombotic state, potentially resulting in life-threatening thrombosis and thromboembolism. The cause of this thrombotic complication is multi-factorial, involving endothelial cells, platelets, adhesive ligands, coagulation, and fibrinolysis. Increasing evidence has shown that hemostatic cells and factors undergo oxidative modifications during the systemic inflammation found in PE patients. However, it is largely unknown how these oxidative modifications of hemostasis contribute to development of the PE-associated prothrombotic state. This knowledge gap has significantly hindered the development of predictive markers, preventive measures, and therapeutic agents to protect women during pregnancy.
  • 2.1K
  • 08 Dec 2020
Topic Review
Product Attributes, Evaluability, and Consumer Satisfaction
Consumer satisfaction is considered essential to long-term business success. Organizations have a need to produce products and services that yield highly satisfied and loyal consumers. Having loyal consumers reduces the costs for firms, since the expenses for acquiring new consumers are much higher than those for keeping existing ones. Studying the factors that determine consumer satisfaction is of vital importance for a company, as consumer satisfaction has been described as the best indicator of a company’s future profits. In addition, several studies have indicated that there are positive effects of consumer satisfaction on overall brand equity and its different aspects, i.e., retailer awareness, retailer associations, the retailers’ perceived quality, and retailer loyalty. Most studies of consumer satisfaction have been based on the overall satisfaction with a product as a whole, while only a few have related consumer satisfaction to the performance of product attributes. We aimed to study which type of product attribute leads to the most satisfaction, thus providing clues for providers to improve their products. We focused on attribute evaluability and analyzed the ease or difficulty in evaluating a product’s attribute. This was assumed to be related to consumer satisfaction Although evaluability has usually been manipulated experimentally, we studied evaluability as a consumer’s perceptions of product attributes. We aimed to show the effects of attribute evaluability on consumer satisfaction outside of the laboratory context, in a real consumer setting. This aim matched the endeavor in research to study the scaling-up of small-scale laboratory findings to larger markets and settings, as advocated by List.  Another basic process in the formation of consumer satisfaction is a judgment of product performance that is relative to the reference point of the product’s performance expectations. In general, the positive disconfirmation of expectations (the perceived realizations of performance exceeding expectations) will lead to consumer satisfaction, whereas negative disconfirmation (the perceived realizations of performance falling short of expectations) induces dissatisfaction. From prospect theory, it is known that negative deviations from a reference point are judged more negatively than their commensurate positive deviations are judged positively, thus indicating asymmetric effects of product evaluations.  A hitherto under-researched topic is whether consumer satisfaction differs when it is due to an attribute expectation disconfirmation of easy-to-evaluate versus difficult-to-evaluate attributes. This topic is theoretically interesting, because such differences may be driven by different psychological processes. Also, it is of practical significance, because it provides a clue to providers in regard to the type of product attributes for which negative expectation disconfirmation needs to be avoided. We consider attribute evaluability as a factor that moderates the effects of attribute disconfirmation on consumer satisfaction.
  • 2.1K
  • 15 Nov 2021
Topic Review
The Experience Economy
The term "Experience Economy" was first used in a 1998 article by B. Joseph Pine II and James H. Gilmore describing the experience economy as the next economy following the agrarian economy, the industrial economy, and the most recent service economy. The concept had been previously researched by many authors. Pine and Gilmore argue that businesses must orchestrate memorable events for their customers, and that memory itself becomes the product: the "experience". More advanced experience businesses can begin charging for the value of the "transformation" that an experience offers, e.g., as education offerings might do if they were able to participate in the value that is created by the educated individual. This, they argue, is a natural progression in the value added by the business over and above its inputs. Although the concept of the experience economy was initially focused in business, it has crossed into tourism, architecture, nursing, urban planning and other fields. The Experience Economy is also considered the main underpinning for customer experience management.
  • 2.1K
  • 19 Oct 2022
Topic Review
Photovoltaic-Thermal (PV-T) Systems for Energy provision in Buildings
Photovoltaic-thermal (PV-T) collectors can be integrated with solar heating and cooling (SHC) technologies to generate electricity, heating and/or cooling. Some studies integrate concentrated PV-T collectors, air-based PV-T collectors and liquid-based PV-T collectors with cooling technologies to provide electricity, heating and cooling to buildings.
  • 2.1K
  • 05 May 2022
Topic Review
Tumor Suppressor
A tumor suppressor gene, or anti-oncogene, is a gene that regulates a cell during cell division and replication. If the cell grows uncontrollably, it will result in cancer. When a tumor suppressor gene is mutated, it results in a loss or reduction in its function; in combination with other genetic mutations this could allow the cell to grow abnormally. The loss of function for these genes may be even more significant in the development of human cancers, compared to the activation of oncogenes. Tumor suppressor genes can be grouped into the following categories caretaker genes, gatekeeper genes, and more recently landscaper genes. Caretaker genes ensure stability of the genome via DNA repair and subsequently when mutated allow mutations to accumulate. Meanwhile gatekeeper genes directly regulate cell growth by either inhibiting cell cycle progression or inducing apoptosis. Lastly landscaper genes regulate growth by contributing to the surrounding environment, when mutated can cause an environment that promotes unregulated proliferation. The classification schemes are evolving as medical advances are being made from fields including molecular biology, genetics, and epigenetics.
  • 2.1K
  • 25 Oct 2022
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