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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
Vitamin D in Dairy Products
The term Vitamin D was created in 1922, describing a vitamin able to promote calcium deposition. Vitamin D in nature is available as ergocalciferol (vitamin D2) or cholecalciferol (vitamin D3).
  • 4.5K
  • 05 Nov 2020
Topic Review
Salt Stress on Plant Growth
Climate change is causing soil salinization, resulting in crop losses throughout the world. The ability of plants to tolerate salt stress is determined by multiple biochemical and molecular pathways. Here we discuss physiological, biochemical, and cellular modulations in plants in response to salt stress. Knowledge of these modulations can assist in assessing salt tolerance potential and the mechanisms underlying salinity tolerance in plants. Salinity-induced cellular damage is highly correlated with generation of reactive oxygen species, ionic imbalance, osmotic damage, and reduced relative water content. Accelerated antioxidant activities and osmotic adjustment by the formation of organic and inorganic osmolytes are significant and effective salinity tolerance mechanisms for crop plants. In addition, polyamines improve salt tolerance by regulating various physiological mechanisms, including rhizogenesis, somatic embryogenesis, maintenance of cell pH, and ionic homeostasis. 
  • 4.5K
  • 08 Jun 2021
Topic Review
Fungicides
Fungicides are considered a vital tool for agriculture, protecting crops against fungal diseases and therefore securing high agricultural productivity. The evolution of technology can provide novel chemical fungicides, such as nanofungicides and chiral fungicides, to address plant resistance development. The extensive use of chemical fungicides leads to a risk for public health, natural waters, and non-target organisms.
  • 4.5K
  • 08 Apr 2022
Topic Review
Cook Stove
A biomass cook stove is heated by burning wood, charcoal, animal dung or crop residue. Cook stoves are commonly used for cooking and heating food in rural households. Nearly half of the world's population, approximately 3 billion people, use solid fuels such as coal, wood, animal dung, and crop residues for their domestic energy needs. Among those who use indoor cooking stoves, the poorest families living in rural areas most frequently use solid fuels, where it continues to be relied on by up to 90% of households. Households in developing countries consume significantly less energy than those in developed countries; however, over 50% of the energy is for cooking food. The average rural family spends 20% or more of its income purchasing wood or charcoal for cooking. The urban poor also frequently spend a significant portion of their income on the purchase of wood or charcoal. Deforestation and erosion often result from harvesting wood for cooking fuel. The main goal of most improved cooking stoves is to reduce the pressure placed on local forests by reducing the amount of wood the stoves consume, and to reduce the negative health impacts associated with exposure to toxic smoke from traditional stoves.
  • 4.5K
  • 25 Oct 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
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
Topic Review
Adaptation
The term “adaptation” is currently used in the climate field. It originated from natural science in the field of population biology and evolutionary ecology. It originally referred to the general characteristics that ensure the survival and reproduction of organic individuals in living environments. The definition of “adaptation” has many attributes, including the two most important points. First is the spatial scale of adaptation, which depends on who is responsible. Second is the nature of adaptive behavior, whether it is spontaneous or conscious or it is planned or prescriptive. The former is usually short-term and tactical adaptation, which is directly related to specific climate change. The latter is more strategic, long-term, and proactive and is usually formulated by government departments and used as part of policy adaptation measures. The adaptation to climate change in the literature is sometimes divergent at the temporal and spatial scales. Short-term adaptation is more of a reaction, and higher-scale adaptation is considered an expected adaptation through policies, projects, and recent plans and actions.
  • 4.5K
  • 15 Nov 2021
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
Widow
A widow is a woman whose spouse has died and a widower is a man whose spouse has died. The treatment of widows and widowers around the world varies.
  • 4.5K
  • 25 Oct 2022
Topic Review
Power Electronics for EV Charging Stations
This paper proposes a design for the Bidirectional electric vehicle charger which is capable of doing both the Grid to Vehicle and Vehicle to Grid power transfer, and the interaction will be made through an automatic smart energy management system(EMS). A simple power electronics topology is used. The user can adjust the output of this charger by using the control signal provided by the controller. The simulation result obtained shows that it has an interaction between the charger and an Energy Management System(EMS) in a residence
  • 4.5K
  • 13 Dec 2022
Topic Review
Built-In Car Navigation System
Driving is based on effective navigation. When using a navigation device, the user interface, the amount and quality of the underlying data and its representation all effect the quality of navigation. This study evaluates whether drivers in three different countries consider these devices to be useful and what functionality they would prefer. An online questionnaire was used to assess built-in navigation systems. The findings from 213 respondents show that current car GPSs are overloaded with features. Regardless of country, drivers simply require more basic functionality in the interface. It was also noted that the embedded functions in these devices are not fully utilized. In addition, many people use the navigation service to enter a new address while the car is moving. It may be worth examining how this option can be better implemented.
  • 4.5K
  • 10 May 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
Niche Sport
Non-conventional sports that do not attract mass audiences
  • 4.5K
  • 21 Dec 2021
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
High-Temperature Shape Memory Alloys
With the aim to improve the strength of high-temperature shape memory alloys, multi-component alloys, including medium- and high-entropy alloys, have been investigated and proposed as new structural materials. Notably, it was discovered that the martensitic transformation temperature could be controlled through a combination of the constituent elements and alloys with high austenite finish temperatures above 500 °C. The irrecoverable strain decreased in the multi-component alloys compared with the ternary alloys. The repeated thermal cyclic test was effective toward obtaining perfect strain recoveries in multi-component alloys, which could be good candidates for high-temperature shape memory alloys.
  • 4.5K
  • 26 Nov 2020
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
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
CO2 Activation on Catalyst Surfaces
Utilizing CO2 as a sustainable carbon source to form valuable products requires activating it by active sites on catalyst surfaces. These active sites are usually in or below the nanometer scale. Some metals and metal oxides in this scale dimension can catalyze the CO2 transformation reactions. Herein, CO2 activation on metal-based catalyst surfaces and how their structures impact the activation process are highlighted.
  • 4.5K
  • 13 Dec 2021
Topic Review Video
Direct Carbon Fuel Cells
Most fuel cells invariably use gaseous or liquid fuels. A fuel cell technology that has attracted attention only recently, the direct carbon fuel cell (DCFC) uses solid fuel (carbon) and converts the chemical energy in the carbon to electricity through its direct participation in the fuel cell reactions and electrochemical oxidation. The fuel use can be almost 100% compared with about 85% for most other fuel cells. The electrical efficiency is expected to be above 70% - almost twice those of current generation coal-fired plants leading to 50% reduction in greenhouse gas emissions. The amount of CO2 for storage/sequestration is also halved. Moreover, the exit gas is almost pure carbon dioxide stream, requiring no or minimal gas separation and processing for sequestration. Therefore, the energy and cost penalties to capture the CO2 will be significantly less than for other technologies. However, the technology is at an early stage of development requiring many complex challenges to be overcome, related to materials and corrosion, fuel delivery mechanism, and system development, before it can be commercialized. Section 19.4 of a recent book by the author gives an overview of this technology focusing on its main issues (Sequeira, 2019.). Two of the main DCFCs, the direct carbon molten carbonate fuel cell (DC-MCFC) and the direct carbon solid oxide fuel cell (DC-SOFC) are described in this topic review. 
  • 4.5K
  • 04 Aug 2021
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