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Topic Review
3D Cell Culture
A 3D cell culture is an artificially created environment in which biological cells are permitted to grow or interact with their surroundings in all three dimensions. Unlike 2D environments (e.g. a Petri dish), a 3D cell culture allows cells in vitro to grow in all directions, similar to how they would in vivo. These three-dimensional cultures are usually grown in bioreactors, small capsules in which the cells can grow into spheroids, or 3D cell colonies. Approximately 300 spheroids are usually cultured per bioreactor.
  • 2.8K
  • 30 Nov 2022
Topic Review
Probiotics in Aquaculture
The Food and Agriculture Organization (FAO) of the United Nations and the World Health Organization (WHO) define probiotics as “Live microorganisms that, when administered in adequate amounts, confer a health benefit on the host”. Possible action modes of probiotics in aquaculture include the regulation of amino and fatty acid metabolisms, the excretion of digestive enzymes and vitamins or cofactors, the production of antagonistic compounds that inhibit bacteria, the enhancement of immune responses, the disruption of the quorum-sensing processes of pathogenic organisms, stress improvement, and heavy-metal detoxification.
  • 2.8K
  • 13 Dec 2023
Topic Review
Bow Shocks in Astrophysics
Bow shocks form the boundary between a magnetosphere and an ambient (or at least surrounding) magnetized medium. This occurs when the magnetic field of an astrophysical object interacts with the nearby flowing ambient plasma. For example, when the solar wind, flowing with a relative speed of order 400 km/s, encounters the magnetic field of Earth, a bow shape boundary forms. For Earth and other magnetized planets, it is the boundary at which the speed of the stellar wind abruptly drops as a result of its approach to the magnetopause. For stars, this boundary is typically the edge of the astrosphere, where the stellar wind meets the interstellar medium.
  • 2.8K
  • 27 Oct 2022
Topic Review
Intestinal Mucus
Overlying gastrointestinal epithelial cells is the transparent mucus layer that separates the lumen from the host. The dynamic mucus layer serves to lubricate the mucosal surface, to protect under-lying epithelial cells, and as a transport medium between luminal contents and epithelial cells. Furthermore, it provides a habitat for commensal bacteria and signals to the underlying immune system. Mucins are highly glycosylated proteins, and their glycocode is tissue-specific and closely linked to the resident microbiota. 
  • 2.8K
  • 19 Feb 2021
Topic Review
Volkswagen Golf Estate
Volkswagen has marketed estate/station wagon variants of its Golf model since its third generation in 1993, through its current seventh generation. Volkswagen marketed the station wagon as Jetta Sportwagen and later the Golf Sportwagen in the United States, the Bora Sportwagen in Mexico, Golf Break and later Golf SW in France, Jetta Variant in Brazil, Vento Variant in Argentina, Jetta Wagon in Canada (only for 2009), Golf Wagon in Canada (onwards from 2010), Golf Estate in the United Kingdom and prominently as the Golf Variant in the domestic market in Germany and most other markets.
  • 2.8K
  • 30 Oct 2022
Topic Review
Open-Cathode PEM Fuel Cells
Fuel cells were first introduced in aircraft as auxiliary power units; however, in recent years, there has been an increasing interest in using fuel cells, batteries, and, sometimes, supercapacitors for the electric propulsion of small aerial vehicles. Open cathode fuel cells are characterized by a light and simple balance of plant but the control of temperature is quite critical under variable conditions of load and altitude, typical of the aerospace application.
  • 2.8K
  • 22 Feb 2024
Topic Review
The Firefighter Problem
The firefighter problem defines a discrete-time process where a fire starts at a designated subset of the vertices of a graph G. At each subsequent discrete time unit, the fire propagates from each burnt vertex to all of its neighbors unless they are defended by a firefighter that can move between any pair of vertices in a single time unit. Once a vertex is burnt or defended, it remains in that state, and the process terminates when the fire can no longer spread.
  • 2.8K
  • 21 Jul 2023
Topic Review
Artificial Intelligence and Cyber-Physical Systems
Modern society is living in an age of paradigm changes. In part, these changes have been driven by new technologies, which provide high performance computing capabilities that enable the creation of complex Artificial Intelligence systems. Those developments are allowing the emergence of new Cyber Systems where the continuously generated data is utilized to build Artificial Intelligence models used to perform specialized tasks within the system. While, on one hand, the isolated application of the cyber systems is becoming widespread, on the other hand, their synchronical integration with other cyber systems to build a concise and cognitive structure that can interact deeply and autonomously with a physical system is still a completely open question, only addressed in some works from a philosophical point of view. From this standpoint, the AI can play an enabling role to allow the existence of these cognitive CPSs.
  • 2.8K
  • 08 Oct 2021
Topic Review
Spectrum
A spectrum (plural spectra or spectrums) is a condition that is not limited to a specific set of values but can vary, without gaps, across a continuum. The word was first used scientifically in optics to describe the rainbow of colors in visible light after passing through a prism. As scientific understanding of light advanced, it came to apply to the entire electromagnetic spectrum. It thereby became a mapping of a range of magnitudes (wavelengths) to a range of qualities, which are the perceived "colors of the rainbow" and other properties which correspond to wavelengths that lie outside of the visible light spectrum. Spectrum has since been applied by analogy to topics outside optics. Thus, one might talk about the "spectrum of political opinion", or the "spectrum of activity" of a drug, or the "autism spectrum". In these uses, values within a spectrum may not be associated with precisely quantifiable numbers or definitions. Such uses imply a broad range of conditions or behaviors grouped together and studied under a single title for ease of discussion. Nonscientific uses of the term spectrum are sometimes misleading. For instance, a single left–right spectrum of political opinion does not capture the full range of people's political beliefs. Political scientists use a variety of biaxial and multiaxial systems to more accurately characterize political opinion. In most modern usages of spectrum there is a unifying theme between the extremes at either end. This was not always true in older usage.
  • 2.8K
  • 11 Nov 2022
Topic Review
Chang Bogo-Class Submarine
The Chang Bogo-class submarine (Hangul: 장보고급 잠수함, Hanja: 張保皐級潛水艦) is a variant of the Type 209 diesel-electric attack submarine initially developed by Howaldtswerke-Deutsche Werft (HDW) of Germany , intended for service with the South Korean Navy and Indonesian Navy. A Daewoo (DSME)-upgraded model of the Chang Bogo class Type 209 is being independently exported by Korea to Indonesia in 2012, after a series of heavy competitions from Russian, French, and German-Turkish consortiums including from Germany's original Type 209. The variant is being considered for possible purchase by Thailand as well, as both newly built and second-hand options. The class is named for ancient Korean maritime figure Jang Bogo.
  • 2.8K
  • 28 Nov 2022
Topic Review
Nature and Cultural Aspects of Astaxanthin
Astaxanthin (AX), a lipid-soluble pigment belonging to the xanthophyll carotenoids family, has recently garnered significant attention due to its unique physical properties, biochemical attributes, and physiological effects.
  • 2.8K
  • 13 Oct 2023
Topic Review
The Dravidian Race in Tamil Social Thought
In the closing decades of the 19th century, a wide range of Tamil authors and public speakers in colonial India became acutely interested in the notion of a Dravidian “race”. This conception of a Dravidian race, rooted in European racial and philological scholarship on the peoples of South India, became an important symbol of Tamil cultural, religious, and social autonomy in colonial and post-colonial Tamil thought, art, politics, and literature.
  • 2.8K
  • 01 Mar 2024
Topic Review
Geopolymer Materials
The advancement of eco-friendly technology in the construction sector has been improving rapidly. As a result, multiple building materials were developed, enhanced, and proposed as replacements for some traditional materials. One notable example presents geopolymer as a substitute for ordinary Portland concrete (OPC). The manufacturing process of (OPC) generates CO2 emissions and a high energy demand, both of which contribute to ozone depletion and global warming. The implementation of geopolymer concrete (GPC) technology in the construction sector provides a path to more sustainable growth and a cleaner environment. This is due to geopolymer concrete’s ability to reduce environmental pollutants and reduce the construction industry’s carbon footprint. This is achieved through its unique composition, which typically involves industrial byproducts like fly ash or slag. These materials, rich in silicon and aluminum, react with alkaline solutions to form a binding gel, bypassing the need for the high-energy clinker production required in OPC. The use of such byproducts not only reduces CO2 emissions but also contributes to waste minimization. Additionally, geopolymer offers extra advantages compared to OPC, including improved mechanical strength, enhanced durability, and good stability in acidic and alkaline settings. Such properties make GPC particularly suitable for a range of construction environments, from industrial applications to infrastructure projects exposed to harsh conditions. 
  • 2.8K
  • 15 Dec 2023
Topic Review
Oxidative Stress in DiGeorge Syndrome
DiGeorge syndrome (DGS) is a rare genetic disease caused by microdeletions of the 22q11.2 region (DGS1). A haploinsufficiency at 10p level has been proposed also as a DGS cause (DGS2). Clinical manifestations are variable. The most frequent features are thymic hypoplasia or aplasia with consequent immune deficiency, cardiac malformations, hypoparathyroidism, facial and palatine abnormalities, variable degrees of cognitive impairment and psychiatric disorders. The specific aim of this descriptive report is to discuss the correlation between oxidative stress and neuroinflammation in DGS patients with microdeletions of the 22q11.2 region. The deleted chromosomic region maps various genes involved in mitochondrial metabolisms, such as DGCR8 and TXNRD2, that could lead to reactive oxygen species (ROS) increased production and antioxidant depletion.
  • 2.8K
  • 08 Mar 2023
Topic Review
Prosopis Species in South Africa
The infestation of invasive plants such as Prosopis species does not only affect the groundwater levels but also threatens the grazing capacity and species richness of most of the semi-arid areas around South Africa. Though Prosopis is invasive, it is however of good nutritive value and can serve as an alternative source of protein and minerals for livestock during the dry season. Bush encroachment by browsable invasive species can be controlled through biological methods by using organisms such as livestock. 
  • 2.8K
  • 30 Jul 2021
Topic Review
A Systematic Approach to Healthcare Knowledge Management Systems
Big data in healthcare contain a huge amount of tacit knowledge that brings great value to healthcare activities such as diagnosis, decision support, and treatment. However, effectively exploring and exploiting knowledge on such big data sources exposes many challenges for both managers and technologists. A healthcare knowledge management system that ensures the systematic knowledge development process on various data in hospitals was proposed. It leverages big data technologies to capture, organize, transfer, and manage large volumes of medical knowledge, which cannot be handled with traditional data-processing technologies. In addition, machine-learning algorithms are used to derive knowledge at a higher level in supporting diagnosis and treatment.
  • 2.8K
  • 13 May 2022
Topic Review
Electron Cloud Densitometry
Electron cloud densitometry is an interdisciplinary technology that uses the principles of quantum mechanics by the electron beam shifting effect. The effect is that the electron beam passing through the electron cloud, in accordance with the general principle of superposition of the system, changes its intensity in proportion to the probability density of the electron cloud. It gives direct visualization of the individual shapes of atoms, molecules and chemical bonds.
  • 2.8K
  • 18 Nov 2022
Topic Review
SARS-CoV-2 and COVID-19
Morbidity and mortality of coronavirus disease 2019 (COVID-19) are due in large part to severe cytokine storm and hypercoagulable state brought on by dysregulated host-inflammatory immune response, ultimately leading to multi-organ failure. Exacerbated oxidative stress caused by increased levels of interleukin (IL)-6 and tumor necrosis factor α (TNF-α) along with decreased levels of interferon α and interferon β (IFN-α, IFN-β) are mainly believed to drive the disease process. Based on the evidence attesting to the ability of glutathione (GSH) to inhibit viral replication and decrease levels of IL-6 in human immunodeficiency virus (HIV) and tuberculosis (TB) patients, as well as beneficial effects of GSH on other pulmonary diseases processes, we believe the use of liposomal GSH could be beneficial in COVID-19 patients.
  • 2.8K
  • 25 Dec 2020
Topic Review
The Cult of the Child
The concept of the “cult of the child” highlights a radical change in child representation. Having been neglected and even disrespected for centuries, children are now valued, and their interests are placed above all others. This change in views of children, reflected in changes in laws, institutions and practices, has also spread to two pillars of our democratic societies, the family and the school, with a number of consequences for parents, teachers and children.
  • 2.8K
  • 30 Mar 2022
Topic Review
Parvovirus
Parvovirus is the common name applied to all the viruses in the Parvoviridae taxonomic family. Parvovirus can also be used specifically for members of one of the two Parvoviridae subfamilies: Parvovirinae, which infect vertebrate hosts, and Densovirinae, which infect invertebrate hosts, are more commonly referred to as densoviruses. In subfamily Parvovirinae there are eight genera, containing a total of 58 recognized species, while in subfamily Densovirinae there are 5 genera and a total of 21 species. Parvoviruses are linear, nonsegmented, single-stranded DNA viruses, with an average genome size of 5-6 kilo base pairs (kbp). They are classified as group II viruses in the Baltimore classification of viruses. Parvoviruses are among the smallest viruses (hence the name, from Latin parvus meaning small) and are 23–28 nm in diameter. Parvoviruses can infect and may cause disease in many animals, from arthropods such as insects and shrimp, to echinoderms such as starfish, and to mammals including humans. Because most of these viruses require actively dividing cells to replicate, the type of tissue infected varies with the age of the animal. The gastrointestinal tract and lymphatic system can be affected at any age, leading to vomiting, diarrhea, and immunosuppression, but cerebellar hypoplasia is only seen in cats that were infected with feline parvovirus (FPV) in the womb or at less than two weeks of age, and disease of the myocardium is seen in puppies infected with canine parvovirus 2 (CPV2) between the ages of three and eight weeks.
  • 2.8K
  • 10 Oct 2022
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