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Topic Review
Chlamydomonas Reinhardtii
Chlamydomonas reinhardtii is a single-cell green alga about 10 micrometres in diameter that swims with two flagella. It has a cell wall made of hydroxyproline-rich glycoproteins, a large cup-shaped chloroplast, a large pyrenoid, and an eyespot that senses light. Chlamydomonas species are widely distributed worldwide in soil and fresh water. Chlamydomonas reinhardtii is an especially well studied biological model organism, partly due to its ease of culturing and the ability to manipulate its genetics. When illuminated, C. reinhardtii can grow photoautotrophically, but it can also grow in the dark if supplied with organic carbon. Commercially, C. reinhardtii is of interest for producing biopharmaceuticals and biofuel, as well being a valuable research tool in making hydrogen.
  • 4.5K
  • 02 Nov 2022
Topic Review
Bifidobacterium Mechanism of Action
Major mechanisms of Bifidobacterium action include modulation of adaptive and innate immunity, enhancement of intestinal epithelial barrier, prevention of pathogen adhesion, and production of antimicrobial compounds.
  • 4.5K
  • 23 Feb 2023
Topic Review
The Potent Phytoestrogen 8-Prenylnaringenin
8-prenylnaringenin (8-PN) is a prenylated flavonoid, occurring, in particular, in hop, but also in other plants. It has proven to be one of the most potent phytoestrogens in vitro known to date, and in the past 20 years, research has unveiled new effects triggered by it in biological systems. These findings have aroused the hopes, expectations, and enthusiasm of a “wonder-drug” for a host of human diseases. However, the majority of 8-PN effects require such high concentrations that they cannot be reached by normal dietary exposure, only pharmacologically; thus, adverse impacts may also emerge.
  • 4.5K
  • 01 Apr 2022
Topic Review
MINIX
Minix (from "mini-Unix") is a POSIX-compliant (since version 2.0), Unix-like operating system based on a microkernel architecture. Early versions of MINIX were created by Andrew S. Tanenbaum for educational purposes. Starting with MINIX 3, the primary aim of development shifted from education to the creation of a highly reliable and self-healing microkernel OS. MINIX is now developed as open-source software. MINIX was first released in 1987, with its complete source code made available to universities for study in courses and research. It has been free and open-source software since it was re-licensed under the BSD license in April 2000.
  • 4.5K
  • 28 Sep 2022
Topic Review
Applications of Tannins
The origin of tannins, their historical evolution, their different types, and their applications are described. Old and established applications are described, as well as the future applications which are being developed at present and that promise to have an industrial impact in the future. The chemistry of some of these applications is discussed where it is essential to understand the tannins and their derivates role. The essential points of each application, their drawbacks, and their chance of industrial application are briefly discussed.
  • 4.5K
  • 29 Jul 2021
Topic Review
Reusable Launch System
A reusable launch system is a launch system that allows for the reuse of some or all of the component stages. To date, several fully reusable suborbital systems and partially reusable orbital systems have been flown. The first reusable spacecraft to reach orbit was the Space Shuttle (in 1981), which failed to accomplish the intended goal of reducing launch costs to below those of expendable launch systems. During the 21st century, commercial interest in reusable launch systems has grown considerably, with several active launchers. SpaceX CEO Elon Musk has said that if one can figure out how to reuse rockets like airplanes then the cost of access to space will be reduced by as much as a factor of a hundred. SpaceX's Falcon 9 rocket has a reusable first stage and capsule (for Dragon flights) with an expendable second stage. SpaceX has been developing a reusable second stage since the late 2010s which, if successful, could make possible the first fully-reusable orbital launch vehicle during the 2020s. Virgin Galactic has flown reusable suborbital spaceplanes, and the suborbital Blue Origin New Shepard rocket has a recoverable boost stage and passenger capsule.
  • 4.5K
  • 12 Dec 2022
Topic Review
Social Class
Social class refers to a hierarchical arrangement of individuals in a society based on factors such as economic status, occupation, education, and cultural capital. It delineates distinct social groups with varying levels of privilege, influencing access to resources, opportunities, and societal advantages.
  • 4.5K
  • 26 Jan 2024
Topic Review
Performance Evaluation of the Board of Directors
Abstract:   Purpose: The objectives of this paper are to analyse both individual and overall performance evaluations of the Board of Directors as carried out by Maltese Listed Companies (MLCs) and to assess the importance of such board evaluations to small shareholders. Design/Approach/Methodology: The study was designed around semi-structured interviews with fifteen MLC representatives and seven stockbrokers, as well as questionnaires administered to twenty-nine small shareholders. Findings: The findings indicate that, while Boards of Director evaluations are carried out in MLCs, they lack the necessary formal structures that specify critical evaluation measures. Thus one may infer that those charged with the responsibility of conducting evaluations are not being well determined. By departing from the recommendations of the Maltese Corporate Governance Code on performance evaluations, MLCs have generally opted to resort to an inward and more restricted style of evaluation, doing away with external or independent parties in the process.   Practical Implications: Recommendations include the promotion of shareholder interest by enhancing their awareness of the benefits they will stand to gain from the process and by involving them more in the process. Originality/Value: The paper considers possible evaluation measures that may be aimed to enhance both shareholder and public confidence in the exercise and also other ways by which it may be improved. It thus contributes to the literature, as yet scarce, which relates to corporate governance in small states.   Keywords: Performance evaluation, corporate governance, board of directors, MLCs.   JEL code: G34. Paper type: Research article.
  • 4.5K
  • 28 May 2020
Topic Review
Evolution of the Domesticated Cat
The domestic cat originated from Near-Eastern and Egyptian populations of the African wildcat, Felis sylvestris lybica. The family Felidae, to which all living feline species belong, arose about ten to eleven million years ago. This family is divided into eight major phylogenetic lineages. The domestic cat is a member of the Felis lineage. A number of investigations have shown that all domestic varieties of cats come from a single species of the Felis lineage, Felis catus. Variations of this lineage are found all over the world and up until recently scientists have had a hard time pinning down exactly which region gave rise to modern domestic cat breeds. Scientists believed that it was not just one incident that led to the domesticated cat but multiple, independent incidents at different places that led to these breeds. More complications arose from the fact that the wildcat population as a whole is very widespread and very similar to one another. These variations of wild cat can and will interbreed freely with one another when in close contact, further blurring the lines between taxa. Recent DNA studies, advancement in genetic technologies, and a better understanding of DNA and genetics as a whole has helped make discoveries in the evolutionary history of the domestic cat.
  • 4.5K
  • 25 Nov 2022
Topic Review
Applications of Quartz Crystal Microbalance
Quartz Crystal Microbalance (QCM) is one of the many acoustic transducers. It is the most popular and widely used acoustic transducer for sensor applications. It has found wide applications in chemical and biosensing fields owing to its high sensitivity, robustness, small sized-design, and ease of integration with electronic measurement systems.
  • 4.5K
  • 18 Jan 2022
Topic Review Peer Reviewed
Cottage Culture in Finland: Development and Perspectives
This entry provides an understanding of the past, present, and future of the Finnish cottage culture to create an overall picture of its development trajectory and its terminology, e.g., villa, in this context denoting a second home. Convenient, ready-made solutions, easy maintenance, a high level of equipment, year-round use, location, and modern and simple architectural styles are important selection criteria for (summer) cottages that belonged only to the wealthy bourgeois class in the 19th century and have taken their present form with a major transformation in Finland since then. Additionally, municipal regulations and increased attention to ecological concerns are other important issues regarding the cottage today. Cottage inheritance has changed over the generations, and the tightening of building regulations and increased environmental awareness are key drivers of the future transformation of cottage culture. Moreover, the increasing demand for single-family and outdoor spaces created by social changes such as remote working, which has become widespread with the COVID-19 pandemic, will make the summer cottage lifestyle even more popular in Finland. It is thought that this entry will contribute to the continuance of the Finnish cottage culture, which is essential for the vitality of countryside municipalities, local development, national culture, and the well-being of Finnish people. 
  • 4.5K
  • 14 Apr 2022
Topic Review
Epoxides Cycloaddition for CO2 Utilization
In the present review (10.3390/pr8050548), CO2 cycloaddition can be seen as a reasonably competent alternative to CO2 transformation, offsetting the high value-added nature by extending material use defer CO2 back to the atmosphere when compared to commodities and fuels such as urea, methanol, and methane.
  • 4.5K
  • 27 Aug 2020
Topic Review
High-Speed Motorized Spindles of CNC Machine Tools
High-speed motorized spindles tend to develop in the direction of high precision, high speed, low energy consumption, high efficiency, and high reliability. 
  • 4.5K
  • 28 Mar 2022
Topic Review
SpaceX Dragon
Dragon, also known as Dragon 1 or Cargo Dragon, was a class of partially reusable cargo spacecraft developed by SpaceX, an American private space transportation company. Dragon was launched into orbit by the company's Falcon 9 launch vehicle to resupply the International Space Station (ISS). During its maiden flight in December 2010, Dragon became the first commercially built and operated spacecraft to be recovered successfully from orbit. On 25 May 2012, a cargo variant of Dragon became the first commercial spacecraft to successfully rendezvous with and attach to the ISS. SpaceX is contracted to deliver cargo to the ISS under NASA's Commercial Resupply Services program, and Dragon began regular cargo flights in October 2012. With the Dragon spacecraft and the Orbital ATK Cygnus, NASA seeks to increase its partnerships with domestic commercial aviation and aeronautics industry. On 3 June 2017, the C106 capsule, largely assembled from previously flown components from the CRS-4 mission in September 2014, was launched again for the first time on CRS-11, with the hull, structural elements, thrusters, harnesses, propellant tanks, plumbing and many of the avionics reused, while the heat shield, batteries and components exposed to sea water upon splashdown for recovery were replaced. SpaceX developed a second version called Dragon 2, which is capable of transporting humans. Flight testing was completed in 2019, after a delay caused by a test pad anomaly in April 2019, which resulted in the loss of a Dragon 2 capsule. The first flight of astronauts on Dragon 2 occurred on the Crew Dragon Demo-2 mission in May 2020. The last flight of the first version of the Dragon spacecraft (Dragon 1) launched 7 March 2020 (UTC); it was a cargo resupply mission (CRS-20) to International Space Station (ISS). This mission was the last mission of SpaceX of the first Commercial Resupply Services (CRS-1) program, and marked the retirement of the Dragon 1 fleet. Further SpaceX commercial resupply flights to ISS under the second Commercial Resupply Services (CRS-2) program use the cargo-carrying variant of the SpaceX Dragon 2 spacecraft.
  • 4.5K
  • 12 Oct 2022
Topic Review
Seed Priming
Seed nano-priming is an efficient process that can change seed metabolism and signaling pathways, affecting not only germination and seedling establishment but also the entire plant lifecycle.
  • 4.5K
  • 13 Jan 2022
Topic Review
Cessna 210
The Cessna 210 Centurion is a six-seat, high-performance, retractable-gear, single-engine, high-wing general aviation aircraft which was first flown in January 1957 and produced by Cessna until 1986.
  • 4.5K
  • 11 Oct 2022
Topic Review
Insect Pests of Brassica oleracea
The propagation and regeneration of Brassica species has been successful using seeds and different explants like petioles, cotyledons, stems and shoot tips. Shoot regeneration and rooting of Brassica species are successfully obtained from cotyledons and hypocotyl explants. The biological cycle length of Brassica species may either differ slightly or may not differ from one species to another. For instance, the seeds of Brassica oleracea take five days to germinate after sowing at 20–25 °C while the seeds of Brassica campestries take about three to five days to germinate after sowing at 20–25 °C. The most common insect pests of economic importance to Brassica oleracea in African smallholder farmers include Plutella xylostella, Helula undalis, Pieris brassicae, Brevycoryne brassicae, Trichoplusia ni and Myzus persicae. Those insect pests infest cabbages at different stages of growth, causing huge damage and resulting into huge yield losses. The African smallholder farmers use cultural and synthetic pesticides to control those insect pests and minimize infestations. The cultural practices are environmental friendly but are ineffective to control the insect pests. Due to ineffectiveness of cultural practices, African smallholder famers use broad-spectrum synthetic pesticides to effectively control the Brassica species insect pests. The improper and misuse of synthetic pesticides result into insect pests resistance towards the insecticides applied, environmental pollution and human health threats. Insect pests such as Plutella xylostella, Hellula undalis, Brevicoryne brassicae and Myzus persicae have developed resistance to a wide range of pesticides used such as cypermethrin, parathion, decamethrin, quinalphos and lamda-cyhalothrin. Therefore, that calls for search of the alternative products which can effectively be used to control those insect pests in the field.
  • 4.5K
  • 28 Oct 2020
Topic Review
Renewable Energy Status in Azerbaijan
Azerbaijan has a well-developed hydrocarbon industry backed with abundant domestic resources. Oil and gas have played a crucial role in the economic revival of the country since independence was regained back in 1991. The legal foundation of the transition to carbon-zero energy generation was laid in the 1990s with a number of acts mentioning the importance of the shift. The government has an ambitious plan to improve the situation, though an action plan with targeted renewables share in production and consumption is still to be prepared.
  • 4.5K
  • 24 Jan 2022
Topic Review
Obiter Dictum
Obiter dictum (usually used in the plural, obiter dicta) is Latin phrase meaning "by the way", that is, a remark in a judgment that is "said in passing". It is a concept derived from English common law, whereby a judgment comprises only two elements: ratio decidendi and obiter dicta. For the purposes of judicial precedent, ratio decidendi is binding, whereas obiter dicta are persuasive only.
  • 4.5K
  • 18 Oct 2022
Topic Review
Power Electronics for Distributed Generation
Power electronics is formed by technologies that, through advanced controls of semiconductor devices, efficiently convert electrical energy for appropriate use in many areas. Distributed generation (DG), mainly renewable energy, is a group of power sources that can be installed in distinct points of the power system or be isolated, such as: wind power, photovoltaic systems, fuel cells, small hydro, and microturbines. Power converters are a crucial technology for the integration of DG into the modern sustainable power system, including microgrids and smart grids structures. They allow correct adaptation, but also enable DG units to fully realize their potential benefits in their wide variety of configurations.
  • 4.5K
  • 23 Mar 2022
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