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Topic Review
Vitamin D—Innate and Acquired Immunity
Globally, vitamin D deficiency is a significant public health problem—a pandemic—that has overtaken iron deficiency as the most common nutritional deficiency in the world. Vitamin D deficiency is associated with many chronic diseases and increases the risk of acute and worsened chronic infections. Both vitamin D and [25(OH]D: calcifediol) and its active form, 1,25-dihydroxyvitamin D [1,25(OH)2D: calcitriol], play critical roles in protecting humans from invasive pathogens, reducing risks of autoimmunity, and maintaining better health. Conversely, low 25(OH)D status increases susceptibility to infections and developing autoimmunity. Individuals obtain optimal results by maintaining serum 25(OH)D concentrations above 50 ng/mL (125 nmol/L) (above 40 ng/mL in the population): this also minimizes community outbreaks and autoimmune disorders. In over 97.5% of people, this can be achieved through daily sun exposure (except in countries far from the equator during winter) or taking between 5,000 and 8,000 IU vitamin D supplements daily (average, ~70 to 90 IU/kg body weight). Only those with gastrointestinal malabsorption, obesity, or on medications that increase catabolism of vitamin D, and a few specific disorders require higher intake.
  • 1.5K
  • 06 Sep 2023
Topic Review
Phycoerythrin from Blue-Green Algae
Phycoerythrin (PE) is a colored, water-soluble pigment–protein complex from the phycobiliprotein (PBP) family and is predominantly found in rhodophytes, cryptophytes, and cyanobacteria. It is a 240 kDa oligomeric chromoprotein with an intense pink/red color. This PBP is a light-harvesting accessory pigment that absorbs wavelengths that chlorophyll cannot. In terms of energy transfer, PE is the first PBP to absorb light and emits energy to phycocyanin (PC) and allophycocyanin (APC), consecutively. PE is characterized by its original spectrum properties, such as fluorescence emission. On the other hand, previous PBP research was focused on PC, and the scientific community realized that PE is endowed with antioxidant potential due to its ability to scavenge free radicals. This allows them to prevent or delay the onset of potentially fatal diseases, such as cancer, heart disease, and hepatotoxicity. The potent antioxidant activity promotes human health and boosts the immune response against infections. These bioactive compounds also resist photooxidative damage, which would otherwise have an adverse impact on crucial cellular machineries, such as proteins, lipids, and DNA. In comparison to PC and APC, the unique fluorescent properties of PE have made it a useful tool in the diagnosis and treatment of tumors. 
  • 1.5K
  • 12 Jan 2023
Topic Review
Type 2 Diabetes
Type 2 diabetes is a disorder characterized by abnormally high blood sugar levels. In this form of diabetes, the body stops using and making insulin properly. Insulin is a hormone produced in the pancreas that helps regulate blood sugar levels. Specifically, insulin controls how much glucose (a type of sugar) is passed from the blood into cells, where it is used as an energy source. When blood sugar levels are high (such as after a meal), the pancreas releases insulin to move the excess glucose into cells, which reduces the amount of glucose in the blood.
  • 1.5K
  • 07 Apr 2023
Topic Review
Mitochondrial Transporter Protein Families
Mitochondrial carriers facilitate the transfer of small molecules across the inner mitochondrial membrane (IMM) to support mitochondrial function and core cellular processes. In addition to the classical SLC25 (solute carrier family 25) mitochondrial carriers, the past decade has led to the discovery of additional protein families with numerous members that exhibit IMM localization and transporter-like properties. These include mitochondrial pyruvate carriers, sideroflexins, and mitochondrial cation/H+ exchangers. These transport proteins were linked to vital physiological functions and disease.
  • 1.5K
  • 20 Jan 2021
Topic Review
Metabolomics and Plant Abiotic Stress
Metabolomics is a technology that generates large amounts of data and contributes to obtaining wide and integral explanations of the biochemical state of a living organism. Plants are continuously affected by abiotic stresses such as water scarcity, high temperatures and high salinity, and metabolomics has the potential for elucidating the response-to-stress mechanisms and develop resistance strategies in affected cultivars.
  • 1.5K
  • 21 May 2021
Topic Review
Physiological Functions of Rice SUT and SWEET transporters
Sugar transporters play important or even indispensable roles in sugar translocation among adjacent cells in the plant. They are mainly composed of sucrose–proton symporter SUT family members and SWEET family members. SUT works as sucrose positive transporter locates at the donor cell side; SWEET usually works at the acceptor cell side as efflux transporter. 
  • 1.5K
  • 02 Dec 2021
Topic Review
Integrated HBIM Framework for Management of Heritage Buildings
Heritage buildings are subject to severe damage due to their exposure to dynamics such as environmental changes, earthquakes, structural loads and so on, thus needing a proper maintenance and management system. However, during the restoration, maintenance, and management process, heritage building practitioners face numerous challenges, such as inefficient project management, financial loss, and project delay. These problems arise due to a lack of digital documentation and updated information management systems. Heritage building management still uses traditional management techniques where heritage information is managed using multiple format systems by different professionals, thus missing collaboration, information integration, and interoperability. Building information modeling (BIM) is presented here as a supporting tool to address these issues.
  • 1.5K
  • 18 Jul 2022
Topic Review
Formwork System Selection in Building Construction Projects
The formwork system (FWS) gives the geometry and strength required by the reinforced concrete (RC) structure to attain the desired form and structural design properties of the cured concrete.
  • 1.5K
  • 05 Sep 2022
Topic Review
Nanotechnology Education
Nanotechnology education involves a multidisciplinary natural science education with courses such as physics, chemistry, mathematics and molecular biology. It is being offered by many universities around the world. The first program involving nanotechnology was offered by the University of Toronto's Engineering Science program, where nanotechnology could be taken as an option. Here is a partial list of universities offering nanotechnology education, and the degrees offered (Bachelor of Science, Master of Science, and/or Ph.D in Nanotechnology).
  • 1.5K
  • 14 Oct 2022
Topic Review
Link Grammar
Link grammar (LG) is a theory of syntax by Davy Temperley and Daniel Sleator which builds relations between pairs of words, rather than constructing constituents in a phrase structure hierarchy. Link grammar is similar to dependency grammar, but dependency grammar includes a head-dependent relationship, whereas Link Grammar makes the head-dependent relationship optional (links need not indicate direction). Colored Multiplanar Link Grammar (CMLG) is an extension of LG allowing crossing relations between pairs of words. The relationship between words is indicated with link types, thus making the Link grammar closely related to certain categorial grammars. For example, in a subject–verb–object language like English, the verb would look left to form a subject link, and right to form an object link. Nouns would look right to complete the subject link, or left to complete the object link. In a subject–object–verb language like Persian, the verb would look left to form an object link, and a more distant left to form a subject link. Nouns would look to the right for both subject and object links.
  • 1.5K
  • 27 Oct 2022
Topic Review
HOTOL
HOTOL, for Horizontal Take-Off and Landing, was a 1980s United Kingdom design for a single-stage-to-orbit (SSTO) spaceplane that was to be powered by an airbreathing jet engine. Development was being conducted by a consortium led by Rolls-Royce and British Aerospace (BAe). Designed as a single-stage-to-orbit (SSTO) reusable winged launch vehicle, HOTOL was to be fitted with a unique air-breathing engine, the RB545 or Swallow, that was under development by British engine manufacturer Rolls-Royce. The propellant for the engine technically consisted of a combination of liquid hydrogen/liquid oxygen; however, it was to employ a new means of dramatically reducing the amount of oxidizer needed to be carried on board by utilising atmospheric oxygen as the spacecraft climbed through the lower atmosphere. Since propellant typically represents the majority of the takeoff weight of a rocket, HOTOL was to be considerably smaller than normal pure-rocket designs, roughly the size of a medium-haul airliner such as the McDonnell Douglas DC-9/MD-80. While HOTOL's proof-of-concept design study was being carried out, attempts were made by both industry and the British government to establish international cooperation to develop, produce, and deploy the spacecraft. In spite of American interest in the programme, there was little appetite amongst the members of the European Space Agency (ESA), and the British government was not prepared to depart from ESA cooperation. Additionally, technical issues were encountered, and there were allegations that comparisons with alternative launch systems such as conventional rocket vehicle using similar construction techniques failed to show much advantage to HOTOL. In 1989, funding for the project ended. The termination of development work on HOTOL led to the formation of Reaction Engines Limited (REL) to develop and produce Skylon, a proposed spacecraft based on HOTOL technologies, including its engine.
  • 1.5K
  • 28 Oct 2022
Topic Review
Personally Identifiable Information
Personal information, described in United States legal fields as either personally identifiable information (PII), or sensitive personal information (SPI), as used in information security and privacy laws, is information that can be used on its own or with other information to identify, contact, or locate a single person, or to identify an individual in context. The abbreviation PII is widely accepted in the U.S. context, but the phrase it abbreviates has four common variants based on personal / personally, and identifiable / identifying. Not all are equivalent, and for legal purposes the effective definitions vary depending on the jurisdiction and the purposes for which the term is being used. (In other countries with privacy protection laws derived from the OECD privacy principles, the term used is more often "personal information", which may be somewhat broader: in Australia's Privacy Act 1988 (Cth) "personal information" also includes information from which the person's identity is "reasonably ascertainable", potentially covering some information not covered by PII.) Under European and other data protection regimes, which centre primarily around the General Data Protection Regulation, the term "personal data" is significantly broader, and determines the scope of the regulatory regime. NIST Special Publication 800-122 defines PII as "any information about an individual maintained by an agency, including (1) any information that can be used to distinguish or trace an individual's identity, such as name, social security number, date and place of birth, mother's maiden name, or biometric records; and (2) any other information that is linked or linkable to an individual, such as medical, educational, financial, and employment information." So, for example, a user's IP address is not classed as PII on its own, but is classified as linked PII. The concept of PII has become prevalent as information technology and the Internet have made it easier to collect PII leading to a profitable market in collecting and reselling PII. PII can also be exploited by criminals to stalk or steal the identity of a person, or to aid in the planning of criminal acts. As a response to these threats, many website privacy policies specifically address the gathering of PII, and lawmakers have enacted a series of legislation to limit the distribution and accessibility of PII. However, PII is a legal concept, not a technical concept, and as noted, it is not utilised in all jurisdictions. Because of the versatility and power of modern re-identification algorithms, the absence of PII data does not mean that the remaining data does not identify individuals. While some attributes may not be uniquely identifying on their own, any attribute can be potentially identifying in combination with others. These attributes have been referred to as quasi-identifiers or pseudo-identifiers. While such data may not constitute PII in the United States, it is highly likely to remain personal data under European data protection law.
  • 1.5K
  • 03 Nov 2022
Topic Review
Mount Polley Tailings Spill
The Mount Polley tailings spill occurred in the Cariboo region of central British Columbia, Canada . The spill began 4 August 2014 with a breach of the Imperial Metals-owned Mount Polley copper, gold and silver mine tailings pond, releasing its water and slurry with years worth of mining waste into Polley Lake. The spill flooded Polley Lake, creating a plug at Hazeltine Creek, and continued into nearby Quesnel Lake and Cariboo River. By 8 August the four-square-kilometre (1.5 sq mi) sized tailings pond had been emptied of the majority of supernatant (process water) that sits atop the settled crushed rock solids (mining waste, or 'tailings'). The cause of the dam breach and subsequent tailings spill has been investigated with a final report published 31 January 2015. Imperial Metals had a history of operating the pond beyond capacity since at least 2011. Remediation and reconstruction has been underway at the site since 2014. These efforts have included investigation on impacts to human health and safety and affected ecosystems while removing the tailings spill, reconstructing creek shorelines, installing fish habitats, and replanting trees and other local vegetation. Investigation by the remediation team showed elevated levels of selenium, arsenic and other metals consistent with historical tests before the dam breach. These initial reports had been concerned about the chemical impact of the tailings spill on the surrounding environment, but it was determined through subsequent investigation and remediation that the challenge posed by tailings spill was physical in nature.
  • 1.5K
  • 07 Nov 2022
Topic Review
Polony Sequencing
Polony sequencing is an inexpensive but highly accurate multiplex sequencing technique that can be used to “read” millions of immobilized DNA sequences in parallel. This technique was first developed by Dr. George Church's group at Harvard Medical School. Unlike other sequencing techniques, Polony sequencing technology is an open platform with freely downloadable, open source software and protocols. Also, the hardware of this technique can be easily set up with a commonly available epifluorescence microscopy and a computer-controlled flowcell/fluidics system. Polony sequencing is generally performed on paired-end tags library that each molecule of DNA template is of 135 bp in length with two 17–18 bp paired genomic tags separated and flanked by common sequences. The current read length of this technique is 26 bases per amplicon and 13 bases per tag, leaving a gap of 4–5 bases in each tag.
  • 1.5K
  • 15 Nov 2022
Topic Review
T-Type Calcium Channels
The role of T-type calcium channels is well established in excitable cells, where they preside over action potential generation, automaticity, and firing. They also contribute to intracellular calcium signaling, cell cycle progression, and cell fate; and, in this sense, they emerge as key regulators also in non-excitable cells. In particular, their expression may be considered a prognostic factor in cancer. Almost all cancer cells express T-type calcium channels to the point that it has been considered a pharmacological target; but, as the drugs used to reduce their expression are not completely selective, several complications develop, especially within the heart. T-type calcium channels are also involved in a specific side effect of several anticancer agents, that act on microtubule transport, increase the expression of the channel, and, thus, the excitability of sensory neurons, and make the patient more sensitive to pain.
  • 1.5K
  • 21 Nov 2022
Biography
Corrado I. Angelini
Corrado Angelini (born August 3, 1941) is a neurologist with a particular interest in neurometabolic and neuromuscular disorders. He received his medical degree at the University of Padova and has done his residency at the University of Padova, Mayo Clinic. He passed FLEX Examination in Minneapolis, in 1973 and obtained the North Dakota State License Examination (No. 3339), since 1973, he has he
  • 1.5K
  • 06 May 2023
Topic Review
Remote Sensing and Monitoring of Marine Pollution
With the rapid development of urbanization and industrialization, human activities have caused marine pollution in three ways: land source, air source, and sea source, leading to the problem of marine environments. Remote sensing, with its wide coverage and fast and accurate monitoring capability, continues to be an important tool for marine environment monitoring and evaluation research.
  • 1.5K
  • 07 Nov 2023
Topic Review
Nepetoideae
Nepetoideae is the most diverse subfamily of Lamiaceae, and some species are well known for their culinary and medicinal uses. In recent years, there has been growing interest in the therapeutic properties of the species of this group regarding inflammatory illnesses.
  • 1.5K
  • 13 Nov 2023
Topic Review
Yeast β-Glucans as Fish Immunomodulators
Administration of immunostimulants in fish is a preventive method to combat infections. A wide variety of these biological molecules exist, among which one of the yeast wall compounds stands out for its different biological activities. The β-glucan that forms the structural part of yeast is capable of generating immune activity in fish by cell receptor recognition. The most frequently used β-glucans for the study of mechanisms of action are those of commercial origin, with doses recommended by the manufacturer. Nevertheless, their immune activity is inefficient in some fish species, and increasing the dose may show adverse effects, including immunosuppression. Conversely, experimental β-glucans from other yeast species show different activities, such as antibacterial, antioxidant, healing, and stress tolerance properties.
  • 1.5K
  • 23 Sep 2022
Topic Review
Pro-Inflammatory Cytokines
Pro-inflammatory cytokines released from tumor cells or stromal cells act in both autocrine and paracrine manners to induce phenotype changes in tumor cells, recruit bone marrow-derived cells, and form an inflammatory milieu, all of which prime a secondary organ’s microenvironment for metastatic cell colonization.
  • 1.5K
  • 30 Sep 2021
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