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Topic Review
Radioactivity in Plastic Materials
All fossil combustible materials, such as coal and crude oil, contain radioactive elements, which origin from the natural decay series of uranium and thorium. The basic material for the synthesis of plastics is crude oil. Therefore, plastics may contain radionuclides. The gamma ray analysis of different rubbish bags used in the city of Basel show a clear contamination with uranium, radium (226Ra and 228Ra) and lead (210Pb), resulting in a yearly charge of 300, 300, 150 and 3,000 MBq each. In comparison with the contamination level of the burning ashes, these charges are not relevant (less than 1% of the content in the slags from the waste incineration). Nonetheless, we note a permanent displacement of long-lived natural radionuclides to landfill-sites.
  • 2.9K
  • 05 Jul 2021
Topic Review
Vitamin D Scarcity in Arctic and  Tropical Peoples
Vitamin D metabolism differs among human populations because the species has adapted to different natural and cultural environments. Two environments are particularly difficult for the production of vitamin D by the skin: the Arctic, where the skin receives little solar UVB over the year; and the Tropics, where the skin is highly melanized and blocks UVB. In both cases, natural selection has favored the survival of those individuals who use vitamin D more efficiently or have some kind of workaround that ensures sufficient uptake of calcium and other essential minerals from food passing through the intestines. Vitamin D scarcity has either cultural or genetic solutions. Cultural solutions include consumption of meat in a raw or boiled state and extended breastfeeding of children. Genetic solutions include higher uptake of calcium from the intestines, higher rate of conversion of vitamin D to its most active form, stronger binding of vitamin D to carrier proteins in the bloodstream, and greater use of alternative metabolic pathways for calcium uptake. Because their bodies use vitamin D more sparingly, indigenous Arctic and Tropical peoples can be misdiagnosed with vitamin D deficiency and wrongly prescribed dietary supplements that may push their vitamin D level over the threshold of toxicity.
  • 2.9K
  • 20 Oct 2022
Topic Review
Cat Body-type Mutation
Cats, like all living organisms, occasionally have mutations that affect their body type. Sometimes, these cat body-type mutations are striking enough that humans select for and perpetuate them. This is not always in the best interests of the cat, as many of these mutations are harmful; some are even lethal in their homozygous form. This article gives a selection of cat body type mutant alleles and the associated mutations with a brief description.
  • 2.9K
  • 29 Sep 2022
Topic Review
Haemophilus Influenzae
Haemophilus influenzae (formerly called Pfeiffer's bacillus or Bacillus influenzae) is a Gram-negative, coccobacillary, facultatively anaerobic capnophilic pathogenic bacterium of the family Pasteurellaceae. The bacterium was argued by some to be the cause of influenza. H. influenzae was first described in 1892 by Richard Pfeiffer during an influenza pandemic when he incorrectly described Haemophilus influenzae as the causative microbe, which explains why the bacteria retains "influenza" in its name. H. influenzae is responsible for a wide range of localized and invasive infections, but influenza is caused by viruses. This species was the first free-living organism to have its entire genome sequenced.
  • 2.9K
  • 23 Nov 2022
Topic Review
Machine Learning and Student Performance Prediction
Improving the quality, developing and implementing systems that can provide advantages to students, and predicting students’ success during the term, at the end of the term, or in the future are some of the primary aims of education. Due to its unique ability to create relationships and obtain accurate results, artificial intelligence and machine learning are tools used in this field to achieve the expected goals.
  • 2.9K
  • 08 Dec 2021
Topic Review
Gender Disparities in the Urban Public Transport
Gender and public transportation studies are critical for a nation’s social and economic development, particularly in a developing country such as Nigeria. Men and women use public transportation due to their different social roles and economic activities. In other words, good public transportation improves or expands opportunities in health, education, and employment. Consequently, understanding the gender differences in accessibility will be crucial to enhancing existing transport services and helping design more efficient transport policies. 
  • 2.9K
  • 23 Jun 2025
Topic Review
Molecular Biology of the ERBB2 Signaling Pathway
Notably, 5% of metastatic colorectal cancer (mCRC) cases harbor Erb-B2 receptor tyrosine kinase 2 (ERBB2) alterations. ERBB2, commonly referred to as human epidermal growth factor receptor 2, is a member of the human epidermal growth factor receptor family of protein tyrosine kinases. In addition to being a recognized therapeutic target in the treatment of gastric and breast malignancies, it is considered crucial in the management of colorectal cancer (CRC). 
  • 2.9K
  • 01 Nov 2022
Topic Review
Vehicle Design and Technology for Reducing Fuel Consumption
In recent times, the significance of advancing road transportation technologies has notably increased. This is mainly driven by the escalating need for road transportation systems that are not only safe but also environmentally sustainable. Moreover, enhancing fuel efficiency in road vehicles (i.e., automobiles) holds the potential to contribute significantly to the reduction of a country’s economic vulnerability (i.e., improved energy security), by reducing the reliance on energy imports. 
  • 2.9K
  • 29 Jan 2024
Topic Review
Maca
Maca (Lepidium meyenii, Lepidium peruvianum) is part of the Brassicaceae family and grows at high altitudes in the Peruvian Andes mountain range (3500–5000 m). Historically, it has been used as a nutrient-dense food and for its medicinal properties, primarily in enhancing energy and fertility.
  • 2.9K
  • 08 Mar 2024
Topic Review
Digital Applications in Energy Sector
Digitalization is a transformation process which has already affected many parts of industry and society and is expected to yet increase its transformative speed and impact. In the energy sector, many digital applications have already been implemented. However, a more drastic change is expected during the next decades. Good understanding of which digital applications are possible and what are the associated benefits as well as risks from the different perspectives of the impacted stakeholders is of high importance. On the one hand, it is the basis for a broad societal and political discussion about general targets and guidelines of digitalization. On the other hand, it is an important piece of information for companies in order to develop and sustainably implement digital applications. This entry provides a structured overview of potential digital applications in the German energy (electricity) sector on the basis of a literature review.
  • 2.9K
  • 14 Apr 2021
Topic Review
Halāl Salami
The quality assessment and authentication of ḥalāl products are issues raising a growing interest in European Community Countries (France, Sweden, Germany, Greece, Spain, Italy), in Switzerland, in Russia and other countries in the world (Asia, the UK, South and North America). Considering that top producers of ḥalāl products (including meat) are countries where Muslims are a minority, future research should take into consideration ḥalāl standards, immigration and integration of qualified Muslim workers.
  • 2.9K
  • 16 Aug 2020
Topic Review
Extinction
In astronomy, extinction is the absorption and scattering of electromagnetic radiation by dust and gas between an emitting astronomical object and the observer. Interstellar extinction was first documented as such in 1930 by Robert Julius Trumpler. However, its effects had been noted in 1847 by Friedrich Georg Wilhelm von Struve, and its effect on the colors of stars had been observed by a number of individuals who did not connect it with the general presence of galactic dust. For stars that lie near the plane of the Milky Way and are within a few thousand parsecs of the Earth, extinction in the visual band of frequencies (photometric system) is roughly 1.8 magnitudes per kiloparsec. For Earth-bound observers, extinction arises both from the interstellar medium (ISM) and the Earth's atmosphere; it may also arise from circumstellar dust around an observed object. Strong extinction in earth's atmosphere of some wavelength regions (such as X-ray, ultraviolet, and infrared) is overcome by the use of space-based observatories. Since blue light is much more strongly attenuated than red light, extinction causes objects to appear redder than expected, a phenomenon referred to as interstellar reddening.
  • 2.9K
  • 18 Oct 2022
Topic Review
Meat Analogue
A meat analogue is a food industry term for a meat-like substance made from vegetarian ingredients. More common terms are plant-based meat, vegan meat, meat substitute, mock meat, meat alternative, imitation meat, or vegetarian meat, or, sometimes more pejoratively, fake meat or faux meat. Meat analogues typically approximate certain aesthetic qualities (such as texture, flavor, appearance) or chemical characteristics of specific types of meat. Many analogues are soy-based (e.g., tofu, tempeh) or gluten-based but now may also be made from pea protein. Other less common analogues include cottage cheese and mycoprotein. Because of their similarity to meats, they are frequently used in dishes and food practices similar to meat. The target market for meat analogues includes vegetarians, vegans, non-vegetarians seeking to reduce their meat consumption, and people following religious dietary laws in Hinduism, Judaism, Islam, Christian vegetarianism, and Buddhism. Increasingly, the global demand for sustainable diets in response to the outsized role animal products play in global warming and other environmental impacts has seen an increase in industries focused on finding substitutes similar to meat. However, the motivation for seeking out mock meats tends to vary depending on consumer group. The market for meat alternatives is highly dependent on "meat-reducers" — a consumer group who is primarily motivated by health consciousness and weight management. Consumers who identify as vegan, vegetarian or pescetarian are more likely to endorse concerns regarding animal welfare and/or environmentalism as primary motivators. Meat substitution has a long history. Tofu, a popular meat analogue made from soybeans, was known in China during the period of the Western Han dynasty (206 BCE – 9 CE). A document written by Tao Gu (903–970) describes how tofu was called "small mutton" and valued as an imitation meat. Meat analogues such as tofu and wheat gluten are associated with Buddhist cuisine in China and other parts of East Asia. In Medieval Europe, meat analogues were popular during the Christian observance of Lent, when the consumption of meat from warm-blooded animals is forbidden. In the 2010s, owing to concern over global warming, demand for meat from a growing middle class, and major investments by companies such as Beyond Meat and Impossible Foods, there was an increase in awareness and the market size for meat analogues in Western and Westernized markets.
  • 2.9K
  • 24 Oct 2022
Topic Review
Side Lobe
In antenna engineering, side lobes or sidelobes are the lobes (local maxima) of the far field radiation pattern of an antenna or other radiation source, that are not the main lobe. The radiation pattern of most antennas shows a pattern of "lobes" at various angles, directions where the radiated signal strength reaches a maximum, separated by "nulls", angles at which the radiated signal strength falls to zero. This can be viewed as the diffraction pattern of the antenna. In a directional antenna in which the objective is to emit the radio waves in one direction, the lobe in that direction is designed to have a larger field strength than the others; this is the "main lobe". The other lobes are called "side lobes", and usually represent unwanted radiation in undesired directions. The side lobe directly behind the main lobe is called the back lobe. The longer the antenna relative to the radio wavelength, the more lobes its radiation pattern has. In transmitting antennas, excessive side lobe radiation wastes energy and may cause interference to other equipment. Another disadvantage is that confidential information may be picked up by unintended receivers. In receiving antennas, side lobes may pick up interfering signals, and increase the noise level in the receiver. The power density in the side lobes is generally much less than that in the main beam. It is generally desirable to minimize the sidelobe level (SLL), which is measured in decibels relative to the peak of the main beam. The main lobe and side lobes occur for both transmitting and receiving. The concepts of main and side lobes, radiation pattern, aperture shapes, and aperture weighting, apply to optics (another branch of electromagnetics) and in acoustics fields such as loudspeaker and sonar design, as well as antenna design. Because an antenna's far field radiation pattern is a Fourier Transform of its aperture distribution, most antennas will generally have sidelobes, unless the aperture distribution is a Gaussian, or if the antenna is so small as to have no sidelobes in the visible space. Larger antennas have narrower main beams, as well as narrower sidelobes. Hence, larger antennas have more sidelobes in the visible space (as the antenna size is increased, sidelobes move from the evanescent space to the visible space).
  • 2.9K
  • 28 Nov 2022
Topic Review
Trique Language
The Triqui (/ˈtriːki/), or Trique, languages are Oto-Manguean languages of Mexico spoken by the Trique people of the state of Oaxaca and the state of Baja California (due to recent population movements). They belong to the Mixtecan branch together with the Mixtec languages and Cuicatec.
  • 2.9K
  • 21 Oct 2022
Topic Review
Multi-Motor Vehicular Systems
With vehicle electrification, autonomous driving, and employment of X-By-Wire technology, mechanical systems are replaced by motor drives improving their efficiency and performance. Thus, vehicular systems are becoming multi-motor systems. In the following,  the case of multi-motor systems in automotive applications is laid out by presenting the different vehicular systems comprising multiple motors.
  • 2.9K
  • 16 Aug 2022
Topic Review
Exposure Routes and Health Risks Associated with Pesticides
There are four main pesticide application methods, including hydraulic spraying, backpack spraying, basal trunk spraying, and aerial spraying. Pesticide application methods are mainly selected by considering the habits of target pests, the characteristics of target sites, and the properties of pesticides. Humans are directly exposed to pesticides in occupational, agricultural, and household activities and are indirectly exposed to pesticides via environmental media, including air, water, soil, and food. Human exposure to pesticides occurs mainly through dermal, oral, and respiratory routes. People who are directly and/or indirectly exposed to pesticides may contract acute toxicity effects and chronic diseases. Although no segment of the general population is completely protected against exposure to pesticides and their potentially serious health effects, a disproportionate burden is shouldered by people in developing countries. Both deterministic and probabilistic human health risk assessments have their advantages and disadvantages and both types of methods should be comprehensively implemented in research on exposure and human health risk assessment. Equipment for appropriate pesticide application is important for application efficiency to minimize the loss of spray solution as well as reduce pesticide residuals in the environment and adverse human health effects due to over-spraying and residues. Policymakers should implement various useful measures, such as integrated pest management (IPM) laws that prohibit the use of pesticides with high risks and the development of a national implementation plan (NIP) to reduce the adverse effects of pesticides on the environment and on human health. 
  • 2.9K
  • 30 Jul 2022
Topic Review
Auction
An auction is usually a process of buying and selling goods or services by offering them up for bids, taking bids, and then selling the item to the highest bidder or buying the item from the lowest bidder. Some exceptions to this definition exist and are described in the section about different types. The branch of economic theory dealing with auction types and participants' behavior in auctions is called auction theory. The open ascending price auction is arguably the most common form of auction in use throughout history. Participants bid openly against one another, with each subsequent bid required to be higher than the previous bid. An auctioneer may announce prices, bidders may call out their bids themselves or have a proxy call out a bid on their behalf, or bids may be submitted electronically with the highest current bid publicly displayed. Auctions were and are applied for trade in diverse contexts. These contexts are antiques, paintings, rare collectibles, expensive wines, commodities, livestock, radio spectrum, used cars, online advertising, even emission trading and many more.
  • 2.9K
  • 08 Nov 2022
Topic Review
Assessment of Bio-Based Polyurethanes
Among numerous synthetic macromolecules, polyurethane in its different forms has proven its sheer dominance and established a reputation as a reliable and trusted material due to its proficiency in terms of superior properties, which include: high mechanical strength and abrasion resistance, good durability, good adhesion, good thermal stability, excellent chemical and weathering resistance. Synthetic polyurethane materials are non-biodegradable, poisonous, and use petrochemical-based raw materials, which are now depleting, leading to a surge in polyurethane production costs. Enormous kinds of available bio-renewable sources as predecessors for the production of polyols and isocyanates have been explored for the development of “greener” PU materials; these bio-based polyurethanes have significant potential to be used as future PU products, with a partial or total replacement of petroleum-based polyurethanes, due to increasing concern about the environment, their relatively low cost and biodegradability.
  • 2.9K
  • 12 Aug 2022
Topic Review
Subject
A subject is a being who has a unique consciousness and/or unique personal experiences, or an entity that has a relationship with another entity that exists outside itself (called an "object"). A subject is an observer and an object is a thing observed. This concept is especially important in Continental philosophy, where 'the subject' is a central term in debates over the nature of the self. The nature of the subject is also central in debates over the nature of subjective experience within the Anglo-American tradition of analytical philosophy. The sharp distinction between subject and object corresponds to the distinction, in the philosophy of René Descartes, between thought and extension. Descartes believed that thought (subjectivity) was the essence of the mind, and that extension (the occupation of space) was the essence of matter.
  • 2.9K
  • 18 Nov 2022
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