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Topic Review
The Normal Bone Marrow Microenvironment
The bone marrow is responsible for providing the body with a constant supply of millions of circulating blood cells and platelets. Haematopoietic stem/progenitor cells (HSPCs) are rare, self-renewing, multipotent progenitors that produce all types of these blood cells via haematopoiesis. Maintaining these HSPCs requires key signals and interactions with both haematopoietic and non-haematopoietic cells within the bone marrow microenvironment. Understanding these cellular communications may provide insight into haematological diseases and uncover better strategies for treatment. 
  • 2.2K
  • 29 Jan 2023
Topic Review
Action Sports
In the last two decades, non-traditional sports activities characterized by elements such as speed, height, and exposure to natural forces knew a rapid increase in global participation. They are generally referred to as action sports (AS), with the terms adventure sports or extreme sports that could be used as interchangeable synonyms.
  • 2.2K
  • 09 Dec 2020
Topic Review
Folate and Migraines
Migraines are a common disease with limited treatment options and some dietary factors are recognized to trigger headaches. Although migraine pathogenesis is not completely known, aberrant DNA methylation has been reported to be associated with its occurrence. Folate, an essential micronutrient involved in one-carbon metabolism and DNA methylation, was shown to have beneficial effects on migraines.
  • 2.2K
  • 09 Oct 2021
Topic Review
Biological Control of Bulb Mites
Mites of the genus Rhizoglyphus (Acari: Acaridae) are serious pests of plants belonging to the orders Liliales and Asparagales such as onions, garlic, lilies, and tulips. Their control by synthetic pesticides is becoming problematic as a result of resistance development in these mites and environmental and health issues. New pest control methods thus need to be developed. Efforts to develop biological control programs for bulb mites have taken place in a number of countries. Several biocontrol agents have been tested against Rhizoglyphus spp. under laboratory and some also under field conditions. The most promising results have been obtained with acaropathogenic/entomopathogenic fungi and predatory mites as described below. Other possible prospective control agents attacking mites are viruses, bacteria, and protista, but except for some bacteria their efficacy against bulb mites has not been investigated yet.
  • 2.2K
  • 29 Jul 2022
Topic Review
Masten Space Systems
Masten Space Systems was an aerospace manufacturer startup company in Mojave, California (formerly in Santa Clara, California) that is developing a line of vertical takeoff, vertical landing (VTVL) rockets, initially for uncrewed research sub-orbital spaceflights and eventually intended to support robotic orbital spaceflight launches. In 2020, NASA awarded Masten a contract for a lunar lander mission; NASA is to pay Masten US$75.9 million for Masten to build and launch a lander called XL-1 to take NASA and other customer payloads to the south pole of the Moon. Masten Mission One will be Masten's first space flight; it is scheduled for launch in November 2023. The company filed for Chapter 11 bankruptcy on 28 July 2022. The company would later be purchased by Astrobotic Technology on 11 September 2022.
  • 2.2K
  • 26 Oct 2022
Topic Review
Pseudohermaphroditism
Pseudohermaphroditism (also spelled pseudo-hermaphroditism) is an old clinical term for an organism that is born with primary sex characteristics of one sex but develops the secondary sex characteristics that are different from what would be expected on the basis of the gonadal tissue (ovary or testis). It can be contrasted with the term true hermaphroditism, which described a condition where testicular and ovarian tissue were present in the same individual. This language has fallen out of favor due to misconceptions and pejorative connotations associated with the terms, and also a shift to nomenclature based on genetics. The term male pseudo-hermaphrodite was used when a testis is present, and the term female pseudo-hermaphrodite was used when an ovary is present. In some cases, external sex organs associated with pseudohermaphroditism look intermediate between a typical clitoris and penis. In other cases, the external sex organs have an appearance that would be expected to be seen with the "opposite" gonadal tissue. Because of this, pseudohermaphroditism is sometimes not identified until puberty or adulthood. Associated conditions include 5-α-reductase deficiency and androgen insensitivity syndrome.
  • 2.2K
  • 16 Nov 2022
Topic Review
Role of Arbuscular Mycorrhizal Fungi in the Ecosystem
Arbuscular mycorrhizal fungi (AMF) form symbiotic relationships with the roots of nearly all land-dwelling plants, increasing growth and productivity, especially during abiotic stress. AMF improves plant development by improving nutrient acquisition, such as phosphorus, water, and mineral uptake. AMF improves plant tolerance and resilience to abiotic stressors such as drought, salt, and heavy metal toxicity.
  • 2.2K
  • 07 Sep 2023
Topic Review
Thermoelectric Generators at Low Operating-Temperatures
Thermoelectric generators (TEGs) are a form of energy harvester and eco-friendly power generation system that directly transform thermal energy into electrical energy. The thermoelectric (TE) method of energy harvesting takes advantage of the Seebeck effect, which offers a simple solution for fulfilling the power-supply demand in almost every electronics system. A high-temperature condition is commonly essential in the working mechanism of the TE device, which unfortunately limits the potential implementation of the device.
  • 2.2K
  • 01 Jul 2021
Topic Review
Knowledge Management for Fourth Industrial Revolution
The Fourth Industrial Revolution (4IR) offers optimum productivity and efficiency via automation, expert systems, and artificial intelligence. The Fourth Industrial Revolution deploys smart sensors, Cyber-Physical Systems (CPS), Internet of Things (IoT), Internet of Services (IoS), big data and analytics, Augmented Reality (AR), autonomous robots, additive manufacturing (3D Printing), and cloud computing for optimization purposes. Knowledge management (KM) is the process of acquiring, constructing, managing, and disseminating knowledge throughout an organization in order to improve project efficiency and effectiveness. In times of crisis, knowledge management has been shown to be a critical tool in healthcare, allowing people all over the world to cope with and manage massive amounts of data in the event of a pandemic.
  • 2.2K
  • 29 Jun 2022
Topic Review
Thermal Decomposition of Plastic Waste
The resources of fossil fuels, such as crude oil, natural gas, and coal, are depleting day by day due to increasing energy demands. Plastic items have witnessed a substantial surge in manufacturing due to their wide range of applications and low cost. Therefore, the amount of plastic waste is increasing rapidly. Hence, the proper management of plastic wastes for sustainable technologies is the need of the hour.
  • 2.2K
  • 24 Aug 2022
Topic Review
Dream Yoga
Dream yoga or Milam (Tibetan: རྨི་ལམ་རྣལ་འབྱོར་, Wylie: rmi lam rnal 'byor, THL: milam naljor; Sanskrit: स्वप्नदर्शन, svapnadarśana)—the Yoga of the Dream State—is a suite of advanced tantric sadhana of the entwined Mantrayana lineages of Dzogchen (Nyingmapa, Ngagpa, Mahasiddha, Kagyu and Bönpo). Dream yoga consists of tantric processes and techniques within the trance Bardos of Dream and Sleep (Standard Tibetan: mi-lam bardo) Six Yogas of Naropa. In the tradition of the tantra, the dream yoga method is usually passed on by a qualified teacher to his/her students after necessary initiation. Various Tibetan lamas are unanimous that it is more of a passing of an enlightened experience rather than any textual information. In a footnote on 'Zhitro' (Tibetan: zhi khro) Namdak & Dixey, et al. (2002: p. 124) identify that the 'dream body' and the 'bardo body' is the 'vision body' (Tibetan: yid lus):
  • 2.2K
  • 28 Sep 2022
Topic Review
Business Process Reengineering
Business process re-engineering (BPR) is a business management strategy, originally pioneered in the early 1990s, focusing on the analysis and design of workflows and business processes within an organization. BPR aimed to help organizations fundamentally rethink how they do their work in order to dramatically improve customer service, cut operational costs, and become world-class competitors. BPR seeks to help companies radically restructure their organizations by focusing on the ground-up design of their business processes. According to early BPR proponent Thomas Davenport (1990), a business process is a set of logically related tasks performed to achieve a defined business outcome. Re-engineering emphasized a holistic focus on business objectives and how processes related to them, encouraging full-scale recreation of processes rather than iterative optimization of sub-processes. Business process reengineering is also known as business process redesign, business transformation, or business process change management.
  • 2.2K
  • 12 Oct 2022
Topic Review
Bitcoin Cash
Bitcoin Cash is a cryptocurrency that is a fork of Bitcoin. Bitcoin Cash is a spin-off or altcoin that was created in 2017. In November 2018, Bitcoin Cash split further into two cryptocurrencies: Bitcoin Cash and Bitcoin SV.
  • 2.2K
  • 21 Oct 2022
Topic Review
4D Printable Smart Hydrogels for Drug Delivery
Hydrogels are three-dimensional crosslinked polymer network structures that can absorb and hold a large quantity of water while retaining a distinct shape. Among modern drug formulations, stimuli-responsive hydrogels, also known as "smart hydrogels," has attracted enormous attention. The fundamental characteristic of these systems is the capacity to change their mechanical properties, swelling capacity, hydrophilicity, permeability of bioactive molecules, etc., in response to a wide range of stimuli, including temperature, pH, light irradiation, magnetic field, biological factors, etc. On the other hand, the expeditious development of 3D printing technologies has revolutionized the fabrication of hydrogel systems for biomedical applications. By combining these two aspects, 4D printing (i.e., 3D printing of smart hydrogels) has emerged as a new promising platform for the development of novel drug delivery systems, which release active ingredients in response to internal or external stimuli.
  • 2.2K
  • 01 Nov 2022
Topic Review
Spatter in Laser Powder Bed Fusion Additive Manufacturing
Spatter is an inherent, unpreventable, and undesired phenomenon in laser powder bed fusion (L-PBF) additive manufacturing. Spatter, metal vapor and molten pool are important physical phenomena in laser-matter interaction. During L-PBF, the spatter formation mechanism can be demonstrated as the hot spatter ejection mainly driven by the instability of the molten pool due to the vapor-induced recoil pressure, and the cold spatter ejection mainly driven by the vapor-induced entrainment of the shielding gas. Spatter behavior has an intrinsic correlation with the forming quality in L-PBF because it leads to metallurgical defects and the degradation of mechanical properties. This impact becomes more severe in the fabrication of large-sized parts during the multi-laser L-PBF process. Therefore, investigations of spatter generation and countermeasures have become more urgent. 
  • 2.2K
  • 19 May 2023
Topic Review
Antibody–Drug Conjugates for Non-Oncological Applications
Typically, antibody–drug conjugates (ADCs) are made up of a humanized antibody and a small-molecule medication connected by a chemical linker. ADCs’ ability to deliver cytotoxic agents to the specific site with reduced side effects showed promising results in oncology. Inspired by these outcomes, scientists explored the potential of antibody–drug conjugates in non-oncological conditions such as arthritis, myasthenia gravis, immunological disorders, and kidney failure. 
  • 2.2K
  • 07 Jul 2023
Topic Review
Two Medicine Formation
The Two Medicine Formation is a geological formation, or rock body, in northwestern Montana and southern Alberta that was deposited between 83.5 ± 0.7 Ma and 70.6 ± 3.4 Ma (million years ago), during Campanian (Late Cretaceous) time. It crops out to the east of the Rocky Mountain Overthrust Belt, and the western portion (about 600 metres or 2,000 feet thick) of this formation is folded and faulted while the eastern part, which thins out into the Sweetgrass Arch, is mostly undeformed plains. Below the formation are the nearshore (beach and tidal zone) deposits of the Virgelle Sandstone, and above it is the marine Bearpaw Shale. Throughout the Campanian, the Two Medicine Formation was deposited between the western shoreline of the Late Cretaceous Interior Seaway and the eastward advancing margin of the Cordilleran Overthrust Belt. The Two Medicine Formation is mostly sandstone, deposited by rivers and deltas.
  • 2.2K
  • 10 Oct 2022
Topic Review
Art-sRNAi for Enhanced Antiviral Resistance
Artificial small RNAs (art-sRNAs) are 21-nucleotide small RNAs designed to recognize and silence complementary target RNAs with high specificity. Art-sRNA-based RNAi (art-sRNAi) tools are extensively used in gene function studies or for improving crops. In particular, numerous studies have reported the successful application of art-sRNAi tools to induce resistance against a large number of RNA and DNA viruses in model and crop species. However, the application of art-sRNAi as an antiviral tool has limitations, such as the difficulty to predict the efficacy of a particular art-sRNA, or the emergence of virus variants with mutated target sites escaping to art-sRNA-mediated degradation. Here, we describe the different classes, features and recent uses of art-sRNAi tools to induce enhanced antiviral resistance in plants. 
  • 2.2K
  • 09 Jul 2020
Topic Review
Tokyō
Tokyō (斗栱・斗拱, more often 斗きょう)[note 1] (also called kumimono (組物) or masugumi (斗組)) is a system of supporting blocks (斗 or 大斗, masu or daito, lit. block or big block) and brackets (肘木, hijiki, lit. elbow wood) supporting the eaves of a Japanese building, usually part of a Buddhist temple or Shinto shrine. The use of tokyō is made necessary by the extent to which the eaves protrude, a functionally essential element of Japanese Buddhist architecture. The system has however always had also an important decorative function. Like most architectural elements in Japan, the system is Chinese in origin (on the subject, see the article Dougong) but has evolved since its arrival into several original forms. In its simplest configuration, the bracket system has a single projecting bracket and a single block, and is called hitotesaki. If the first bracket and block group support a second similar one, the whole system is called futatesaki, if three brackets are present it is called mitesaki, and so on until a maximum of six brackets as in the photo to the right. Each supporting block in most cases supports, besides the next bracket, a U-shaped supporting bracket set at 90° to the first (see photos in the gallery below). The Protection of Cultural Properties logo (see gallery below) represents a tokyō, considered an element of Japanese architecture which stands for the continuity in time of cultural property protection.
  • 2.2K
  • 14 Oct 2022
Topic Review
Clipboard (Computing)
The clipboard is a buffer that some operating systems provide for short-term storage and transfer within and between application programs. The clipboard is usually temporary and unnamed, and its contents reside in the computer's RAM. The clipboard provides an application programming interface by which programs can specify cut, copy and paste operations. It is left to the program to define methods for the user to command these operations, which may include keybindings and menu selections. When an element is copied or cut, the clipboard must store enough information to enable a sensible result no matter where the element is pasted. Application programs may extend the clipboard functions that the operating system provides. A clipboard manager may give the user additional control over the clipboard. Specific clipboard semantics vary among operating systems, can also vary between versions of the same system, and can sometimes be changed by programs and by user preferences. Windows, Linux and macOS support a single clipboard transaction.
  • 2.2K
  • 19 Oct 2022
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