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Topic Review
Hyacinthus orientalis L.
Hyacinthus orientalis L., commonly known as hyacinth, is one of the most important cultivated plants around the world. The cultivars of this species are characterised by their flowers with strong fragrances and a wide range of attractive colours, which make them a beloved option among ornamentals. The chloroplast genomes of Hyacinthus cultivars ranged from 154,458 bp to 154,641 bp, while those of Bellevalia paradoxa and Scilla siberica were 154,020 bp and 154,943 bp, respectively. Each chloroplast genome was annotated with 133 genes, including 87 protein-coding genes, 38 transfer RNA genes and 8 ribosomal RNA genes.
  • 3.2K
  • 17 Jun 2022
Topic Review
Nitrogen Turbine Engine
An ever-increasing demand for electrical power and soaring levels of energy consumption around the world have led to an energy crisis. Thus, this entry focuses on the conventional technologies against those of newer developments in electrical power generation such as using nitrogen generators. The nitrogen generator method is most appealing as it is a seemingly free energy already existing in nature. A nitrogen generator with a 5000 (Nm3/h) capacity has the potential to be used to analyze gas composition and the results are compared with the gas composition of a conventional steam turbine, which is used to pressurize 6000 (kWh) injection steam turbines. The magnetic bearing must be installed in both systems to modify all centrifuged systems which reduces all energy consumption in all systems by more than 50%. Artificial intelligence is used with the machine to analyze and control nitrogen gas flow to provide a more precise evaluation resulting in a more efficient technology. It should further be noted that the nitrogen turbine is superior to the steam turbine because it does not require the burning of fossil fuel to generate power. Hence, it is crucial to modify conventional technologies to improve energy sustainability and begin the long task of tackling environmental issues.
  • 3.2K
  • 12 Oct 2021
Topic Review
Egyptian Six-Rowed Barley (Hordeum vulgare L.)
Barley (Hordeum vulgare L.) is one of the main and oldest cereal crops on Earth. Worldwide, its grain production is ranked fourth after maize, rice, and wheat. Barley is generally considered a poor man’s crop because it is easy to cultivate, with few requirements, and has a high capacity for adaptation to harsh environments. Some literature estimates the age of barley at 11,000 years. However, six-rowed barley did not arise until after 6000 BC. Archaeological evidence has dated barley cultivation to 5000–6000 BC in Egypt. Barley products, especially bread and beer, comprised a complete diet in ancient Egypt.
  • 3.2K
  • 11 Dec 2021
Topic Review
List of Volunteer Awards
This is a list of awards issued by organisations and governmental bodies honoring the contributions of volunteers (unpaid staff). Whereas many organisations honor volunteers who serve within those individual organisations, these awards listed here recognize volunteers contributing to a variety of nonprofit organisations, non-governmental organisations, charities, civil society organizations and communities.
  • 3.2K
  • 30 Oct 2022
Topic Review
Degua Tembien
Dogu'a Tembien (Template:Lang-ti, "Upper Tembien", sometimes transliterated as Degua Tembien) is one of the woredas in the Tigray Region of Ethiopia. It is named in part after the former province of Tembien. Nowadays, the mountainous district is part of the Southeastern Tigray Zone. The administrative centre of this woreda is Hagere Selam.
  • 3.2K
  • 01 Nov 2022
Topic Review
Environmental Monitoring Applications
Concerns about global environmental challenges, such as the alarming increase in pollution of oceans, waterways, land, and air, are becoming more and more prevalent in contemporary society. Environmental pollution has evolved into more than a health concern because of global industrialization and mass consumption patterns; it now represents a danger to whole ecosystems. It is critical to comprehend its causes and mitigation strategies. Adequate and timely environmental data are required for risk forecasting and early warning for environmental disasters.
  • 3.2K
  • 23 Nov 2022
Topic Review
Nature Imagery and Mystery on Attention Restoration
The attention restoration theory centres on the environment’s capacity to restore attentional deficits and suggests that there are certain qualities in the environment that restore attention, which leads to improvements in our physical, mental, and social well-being. An environment can be restorative through the activation of involuntary attention, which limits the need for directed attention.
  • 3.2K
  • 29 Nov 2022
Topic Review
Energy Poverty
The term “energy poverty” usually refers to the lack of affordability or of access to basic energy services to meet one’s most common needs, such as lighting, cooking, heating and cooling.
  • 3.2K
  • 15 Oct 2021
Topic Review
Tropical Savanna Climate
Tropical savanna climate or tropical wet and dry climate is a type of climate that corresponds to the Köppen climate classification categories Aw (for a dry winter) and As (for a dry summer). Tropical savanna climates have monthly mean temperatures above 18 °C (64 °F) in every month of the year and typically a pronounced dry season, with the driest month having less than 60 mm (2.36 inches) of precipitation and also less than [math]\displaystyle{ 100-\left (\frac{Total\ Annual\ Precipitation\ (mm)}{25} \right) }[/math] of precipitation :200–1 This latter fact is in direct contrast to a tropical monsoon climate, whose driest month sees less than 60 mm of precipitation but has more than [math]\displaystyle{ 100-\left (\frac{Total\ Annual\ Precipitation\ (mm)}{25} \right) }[/math] of precipitation. In essence, a tropical savanna climate tends to either see less rainfall than a tropical monsoon climate or have more pronounced dry season(s). In tropical savanna climates, the dry season can become severe, and often drought conditions prevail during the course of the year. Tropical savanna climates often feature tree-studded grasslands, rather than thick jungle. It is this widespread occurrence of tall, coarse grass (called savanna) which has led to Aw and As climates often being referred to as tropical savanna. However, there is some doubt whether tropical grasslands are climatically induced. Additionally, pure savannas, without trees, are the exception rather than the rule.
  • 3.2K
  • 24 Nov 2022
Topic Review
Picrolite Raw Material on Cyprus
Picrolite is a soft, green massive, banded or crudely fibrous metamorphic rock with a hardness of 3.5, a waxy feel and a conchoidal to subconchoidal fracture (massive), whilst crudely fibrous varieties splinter easily. Picrolite artefacts comprise some of the most distinctive material remains in the prehistory of the island of Cyprus, in the Eastern Mediterranean. Picrolite exploitation dates from at least 12,000 years ago for the manufacture of personal ornaments and items with a symbolic function.
  • 3.2K
  • 21 Apr 2022
Topic Review
Deacetylation
Acetylation (or in IUPAC nomenclature ethanoylation) describes a reaction that introduces an acetyl functional group into a chemical compound. Deacetylation is the removal of an acetyl group. Acetylation refers to the process of introducing an acetyl group (resulting in an acetoxy group) into a compound, namely the substitution of an acetyl group for an active hydrogen atom. A reaction involving the replacement of the hydrogen atom of a hydroxyl group with an acetyl group (CH3CO) yields a specific ester, the acetate. Acetic anhydride is commonly used as an acetylating agent reacting with free hydroxyl groups. For example, it is used in the synthesis of aspirin, heroin, and THC-O-acetate.
  • 3.2K
  • 29 Nov 2022
Topic Review
Risk of Trigonelline in Coffee and Coffee By-Products
Trigonelline is a bioactive pyridine alkaloid that occurs naturally in high concentrations in coffee (up to 7.2 g/kg) and coffee by-products (up to 62.6 g/kg) such as coffee leaves, flowers, cherry husks or pulp, parchment, silver skin, and spent grounds. In the past, coffee by-products were mostly considered waste and discarded. However, the use of coffee by-products as food has attracted interest because of their economic and nutritional value and the environmental benefits of sustainable resource use. Their authorization as so-called novel foods in the European Union may lead to increased oral exposure of the general population to trigonelline. 
  • 3.2K
  • 21 Apr 2023
Topic Review
Indoor Positioning
The indoor positioning system (IPS) is becoming increasing important in accurately determining the locations of objects by the utilization of micro-electro-mechanical-systems (MEMS) involving smartphone sensors, embedded sources, mapping localizations, and wireless communication networks. 
  • 3.2K
  • 14 Jan 2021
Topic Review
Lahar
A lahar ( /ˈlɑːhɑːr/, from Template:Lang-jv) is a violent type of mudflow or debris flow composed of a slurry of pyroclastic material, rocky debris and water. The material flows down from a volcano, typically along a river valley. Lahars are extremely destructive: they can flow tens of metres per second, they have been known to be up to 140 metres (460 ft) deep, and large flows tend to destroy any structures in their path. Notable lahars include those at Mount Pinatubo and Nevado del Ruiz, the latter of which killed thousands of people in the town of Armero.
  • 3.2K
  • 17 Oct 2022
Topic Review Peer Reviewed
Director Interlocks: Information Transfer in Board Networks
Director interlocks occur when a board member or an executive of a firm sits on the board of directors of another firm. As an essential social network application in the business world, interlocking directorates are documented to be non-trivial from the 1930s and continue to gain popularity thereafter. Corporate information and business practices can be transferred to another firm through an interlocking director sitting on both companies’ boards. Such information dissemination leads to changes in an interlocking firm’s decision-making processes. Existing business research attempts to decipher the underlying reasons why board interlocks become prevalent, how and what information is being transferred through this channel, and the intended or unintended consequences to firm strategic, governance, financing, and accounting practices. We first introduce theoretical research on board interlocks in management and then follow up with empirical evidence in finance and accounting. Since extant studies have not reached a consensus on various consequences of board interlocks, we contribute to the literature by summarizing the findings from multi-business disciplines, discussing their advantages and disadvantages, and calling for more research on the topic.
  • 3.2K
  • 10 Jan 2024
Topic Review
Lemniscatic Elliptic Function
In mathematics, a lemniscatic elliptic function is an elliptic function related to the arc length of a lemniscate of Bernoulli studied by Giulio Carlo de' Toschi di Fagnano in 1718. It has a square period lattice and is closely related to the Weierstrass elliptic function when the Weierstrass invariants satisfy g2 = 1 and g3 = 0. In the lemniscatic case, the minimal half period ω1 is real and equal to where Γ is the gamma function. The second smallest half period is pure imaginary and equal to iω1. In more algebraic terms, the period lattice is a real multiple of the Gaussian integers. The constants e1, e2, and e3 are given by The case g2 = a, g3 = 0 may be handled by a scaling transformation. However, this may involve complex numbers. If it is desired to remain within real numbers, there are two cases to consider: a > 0 and a < 0. The period parallelogram is either a square or a rhombus.
  • 3.2K
  • 24 Oct 2022
Topic Review
Ammi Visnaga L.
Ammi visnaga L. (Visnaga daucoides Gaertn., Family Apiaceae), also known as Khella Baldi or toothpick weed, is an annual or biennial herb indigenous to the Mediterranean region of North Africa, Asia, and Europe. Nowadays, it is used in modern medicine to treat many aliments such as renal colic and coronary insufficiency, and is used as an antioxidant, antifungal, and antibacterial, with a larvicidal effect on mosquito larvae. 
  • 3.2K
  • 05 Nov 2021
Topic Review
Structure and Bonding in Planar Hypercoordinate Carbon Compounds
The term hypercoordination refers to the extent of the coordination of an element by its normal value. In the hypercoordination sphere, the element can achieve planar and/or non-planar molecular shape. Hence, planar hypercoordinate carbon species violate two structural rules: (i) The highest coordination number of carbon is four and (ii) the tetrahedral orientation by the connected elements and/or groups. The unusual planar orientations are mostly stabilized by the electronic interactions of the central atom with the surrounding ligands. Primary knowledge of the planar hypercoordinate chemistry will lead to its forthcoming expansion. Experimental and theoretical interests in planar tetracoordinate carbon (ptC), planar pentacoordinate carbon (ppC), and planar hexacoordinate carbon (phC) are continued. The proposed electronic and mechanical strategies are helpful for the designing of the ptC compounds. Moreover, the 18-valence electron rule can guide the design of new ptC clusters computationally as well as experimentally. However, the counting of 18-valence electrons is not a requisite condition to contain a ptC in a cluster. Furthermore, this ptC idea is expanded to the probability of a greater coordination number of carbon in planar orientations. Unfortunately, until now, there are no such logical approaches to designing ppC, phC, or higher-coordinate carbon molecules/ions. There exist a few global minimum structures of phC clusters identified computationally, but none have been detected experimentally. All planar hypercoordinate carbon species in the global minima may be feasible in the gas phase.
  • 3.2K
  • 26 Dec 2022
Topic Review
Bioactive Compounds from Marine Sponges
Marine sponges are sessile invertebrates that can be found in temperate, polar and tropical regions. They are known to be major contributors of bioactive compounds, which are discovered in and extracted from the marine environment. The compounds extracted from these sponges are known to exhibit various bioactivities, such as antimicrobial, antitumor and general cytotoxicity.
  • 3.2K
  • 25 May 2021
Topic Review
10q26 Deletion Syndrome
10q26 deletion syndrome is a condition that results from the loss (deletion) of a small piece of chromosome 10 in each cell. The deletion occurs on the long (q) arm of the chromosome at a position designated 10q26.
  • 3.2K
  • 26 Aug 2021
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