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Topic Review
Corporate Social Responsibility Preferences in South Africa
A firm’s corporate social responsibility (CSR) approach can encompass a wide variety of activities. These may include philanthropy (donating to charities), volunteering by employees, ethical labor practices, and implementing environmentally friendly operations. Diverse stakeholders and nationalities may view certain social initiatives as less or more important than others. As a result, firms respond by prioritizing those CSR activities that stakeholders in their operating environment consider important. This leads to firms having CSR preferences for some social and environmental activities over others. Traditionally, CSR in South Africa was delivered through corporate social investment (CSI): a philanthropic effort with firms implementing their social responsibility through charitable donations targeted at the education and healthcare of a firm’s surrounding communities.
  • 5.3K
  • 13 Apr 2022
Topic Review
The Use of “Lifestyle” in Health Psychology
Lifestyle is a complex and often generic concept that has been used and defined in different ways in scientific research. There is no single definition of lifestyle, and various fields of knowledge have developed theories and research variables that are also distant from each other. In health psychology, the use of this concept has spread widely, especially in the preventive medicine sector, despite a definition that is not always precise and unambiguous. Indeed, it is often confused and assimilated to the health behaviours that have been defined as behavioural patterns, actions, and habits that relate to health maintenance, to health restoration and health improvement. There are two main definitions of lifestyles. The first one was formulated by the WHO, for which lifestyle is defined as “patterns of (behavioural) choices from the alternatives that are available to people according to their socio-economic circumstances and the ease with which they are able to choose certain ones over others”. The second major definition of lifestyle formulated by Cockerham is “collective patterns of health-related behaviour based on choices from options available to people according to their life chances”.
  • 5.3K
  • 09 Mar 2023
Topic Review
Cylinder Block
The cylinder block is an integrated structure comprising the cylinder(s) of a reciprocating engine and often some or all of their associated surrounding structures (coolant passages, intake and exhaust passages and ports, and crankcase). The term engine block is often used synonymously with "cylinder block" (although technically distinctions can be made between en bloc cylinders as a discrete unit versus engine block designs with yet more integration that comprise the crankcase as well). In the basic terms of machine elements, the various main parts of an engine (such as cylinder(s), cylinder head(s), coolant passages, intake and exhaust passages, and crankcase) are conceptually distinct, and these items can all be made as discrete pieces that are bolted together. Such construction was very widespread in the early decades of the commercialization of internal combustion engines (1880s to 1920s), and it is still sometimes used in certain applications where it remains advantageous (especially very large engines, but also some small engines). However, it is no longer the normal way of building most petrol engines and diesel engines, because for any given engine configuration, there are more efficient ways of designing for manufacture (and also for maintenance and repair). These generally involve integrating multiple machine elements into one discrete part, and doing the making (such as casting, stamping, and machining) for multiple elements in one setup with one machine coordinate system (of a machine tool or other piece of manufacturing machinery). This yields lower unit cost of production (and/or maintenance and repair). Today most engines for cars, trucks, buses, tractors, and so on are built with fairly highly integrated design, so the words "monobloc" and "en bloc" are seldom used in describing them; such construction is often implicit. Thus "engine block", "cylinder block", or simply "block" are the terms likely to be heard in the garage or on the street.
  • 5.3K
  • 28 Sep 2022
Topic Review
Cryptocurrencies in Accounting
The International Financial Reporting Standards Interpretations Committee (IFRSIC) (2019) proposed that the IAS 2 Inventories accounting standard is the accounting rule that best fits the holding of cryptocurrencies. As in the ordinary course of business, when holders want to sell their crypto assets, the best accounting rule is the IAS 2 Inventories. The IFRSIC (2019) also proposed that if the IAS 2 Inventories accounting standard is not appropriate for holdings of cryptocurrencies, another good choice is the IAS 38 Intangible Assets accounting standard. In most cases, IAS 38 will be the best accounting standard for holdings of cryptocurrencies.
  • 5.3K
  • 05 May 2022
Topic Review
Major Histocompatibility Complex Class II Presentation in Autoimmunity
Antigen presentation by major histocompatibility complex class II (MHC-II) molecules is crucial for eliciting an efficient immune response by CD4+ T cells and maintaining self-antigen tolerance. Some MHC-II alleles are known to be positively or negatively associated with the risk of the development of different autoimmune diseases (ADs), including those characterized by the emergence of autoreactive T cells. Apparently, the MHC-II presentation of self-antigens contributes to the autoimmune T cell response, initiated through a breakdown of central tolerance to self-antigens in the thymus. 
  • 5.3K
  • 02 Feb 2023
Topic Review
Active Pixel Sensor
An active-pixel sensor (APS) is an image sensor where each picture element ("pixel") has a photodetector and an active amplifier. There are many types of integrated circuit active pixel sensors including the complementary metal–oxide–semiconductor (CMOS) APS used most commonly in cell phone cameras, web cameras, most digital pocket cameras since 2010, in most digital single-lens reflex cameras (DSLRs) and Mirrorless interchangeable-lens cameras (MILCs). Such an image sensor is produced using CMOS technology (and is hence also known as a CMOS sensor), and has emerged as an alternative to charge-coupled device (CCD) image sensors. The term 'active pixel sensor' is also used to refer to the individual pixel sensor itself, as opposed to the image sensor; in that case the image sensor is sometimes called an active pixel sensor imager, or active-pixel image sensor.
  • 5.3K
  • 23 Nov 2022
Topic Review
Remote Attestation
Remote Attestation (RA) is a security mechanism to remotely detect adversarial presence on untrusted devices in order to guarantee their trustworthiness. RA runs as a two-party security protocol in which a trusted party (i.e., verifier) assures the integrity of the untrusted remote device (i.e., prover). Software-based RA approaches aim at verifying device integrity without relying on specialized hardware components. Despite their limited security guarantees, software-based RA approaches bring opportunities in attesting legacy and resource-constrained Internet of Things (IoT) devices, in which the presence of a hardware root-of-trust is not always a realistic assumption.
  • 5.3K
  • 31 Jan 2022
Topic Review
Energy Use in Greenhouses in the EU
High energy systems, which are more dominant in northern Europe, are generally heavily climate controlled and energy use is dominated by heating and cooling processes, while low energy systems, which are dominant in southern Europe, show a mixture of energy uses including heating, cooling, irrigation, lighting, fertilisers, and pesticides.
  • 5.3K
  • 27 May 2022
Topic Review
Carnitine in Mitochondrial Fatty Acid Transport and β-Oxidation
l-Carnitine is an amino acid derivative widely known for its involvement in the transport of long-chain fatty acids into the mitochondrial matrix, where fatty acid oxidation occurs. Moreover, l-Carnitine protects the cell from acyl-CoA accretion through the generation of acylcarnitines.
  • 5.3K
  • 11 Nov 2021
Topic Review
Hatha Yoga
Hatha yoga is a branch of Yoga, one of the six schools of Hinduism. The word haṭha literally means "force" and thus alludes to a system of physical techniques.:770:527 In India hatha yoga is associated in popular tradition with the 'Yogis' of the Natha Sampradaya through its mythical founder Matsyendranath. Matsyendranath, also known as Minanath or Minapa in Tibet, is celebrated as a saint in both Buddhist and Hindu tantric and hatha yoga schools. However, James Mallinson associates hatha yoga with the Dashanami Sampradaya and the mystical figure of Dattatreya. According to the Dattatreya Yoga Śastra, there are two forms of hatha yoga: one practiced by Yajñavalkya consisting of the eight limbs of ashtanga yoga and another practiced by Kapila consisting of eight mudras. Currently, the oldest dated text to describe hatha yoga, the Amṛtasiddhi, comes from a tantric Buddhist milieu. The oldest texts to use the actual verbiage of hatha are also Vajrayana Buddhist. In the 20th century, hatha yoga, particularly asanas (the physical postures), became popular throughout the world as a form of physical exercise, and is now colloquially termed simply as "yoga."
  • 5.3K
  • 24 Nov 2022
Topic Review
Natural Preservatives for Fish
Fish is extremely perishable as a result of rapid microbial growth naturally present in fish or from contamination. Synthetic preservatives are widely used in fish storage to extend shelf life and maintain quality and safety. Natural preservatives from microorganisms, plants, and animals have been shown potential in replacing the chemical antimicrobials. Bacteriocins and organic acids from bacteria showed good antimicrobial activities against spoilage bacteria. Plant-derived antimicrobials could prolong fish shelf life and decrease lipid oxidation. Animal-derived antimicrobials also have good antimicrobial activities.
  • 5.3K
  • 25 Jun 2021
Topic Review
Institutional Translation
Institutional Translation refers to translation activities or translated works initiated or benefited by institutions.
  • 5.3K
  • 02 Sep 2021
Topic Review
Democratic Deficit in the European Union
The notion of a democratic deficit within the European Union (EU) is the idea that the governance of the EU lacks democratic legitimacy. This led in part to an elected European Parliament being created in 1979 and given the power to approve or reject EU legislation. Since then, usage of the term has broadened to describe newer issues facing the European Union. However voter turnout has fallen consecutively at the seven elections since the first election in 1979 and voter turnout in the 2014 election stood at 42.54% of all European voters. This is the lowest of any national election in the 28 countries of the European Union where turnout at national elections averages 68% across the EU. Opinions differ as to whether the EU has a democratic deficit or how it should be remedied if it exists. Pro-Europeans (i.e. those in favour of the EU) argue that the European Union should reform its institutions to make them more accountable, while Eurosceptics argue that the EU should reduce its powers and often campaign for withdrawal from the EU.
  • 5.3K
  • 23 Nov 2022
Topic Review
Observer Effect
In physics, the observer effect is the disturbance of an observed system by the act of observation. This is often the result of instruments that, by necessity, alter the state of what they measure in some manner. A common example is checking the pressure in an automobile tire; this is difficult to do without letting out some of the air, thus changing the pressure. Similarly, seeing non-luminous objects requires light hitting the object, and causing it to reflect that light. While the effects of observation are often negligible, the object still experiences a change. This effect can be found in many domains of physics, but can usually be reduced to insignificance by using different instruments or observation techniques. A notable example of the observer effect occurs in quantum mechanics, as demonstrated by the double-slit experiment. Physicists have found that observation of quantum phenomena can change the measured results of this experiment. Despite the "observer effect" in the double-slit experiment being caused by the presence of an electronic detector, the experiment's results have been misinterpreted by some to suggest that a conscious mind can directly affect reality. The need for the "observer" to be conscious is not supported by scientific research, and has been pointed out as a misconception rooted in a poor understanding of the quantum wave function ψ and the quantum measurement process.
  • 5.3K
  • 29 Nov 2022
Topic Review
Serotonin
Serotonin (5-hydroxytryptamine, 5-HT) plays two important roles in humans—one central and the other peripheral—depending on the location of the 5-HT pools of on either side of the blood-brain barrier. In the central nervous system it acts as a neurotransmitter, controlling such brain functions as autonomic neural activity, stress response, body temperature, sleep, mood and appetite. This role is very important in intensive care, as in critically ill patients multiple serotoninergic agents like opioids, antiemetics and antidepressants are frequently used. High serotonin levels lead to altered mental status, deliria, rigidity and myoclonus, together recognized as serotonin syndrome. In its role as a peripheral hormone, serotonin is unique in controlling the functions of several organs. In the gastrointestinal tract it is important for regulating motor and secretory functions. Apart from intestinal motility, energy metabolism is regulated by both central and peripheral serotonin signaling. It also has fundamental effects on hemostasis, vascular tone, heart rate, respiratory drive, cell growth and immunity. Serotonin regulates almost all immune cells in response to inflammation, following the activation of platelets. 
  • 5.2K
  • 18 May 2021
Topic Review
Southeast Asian Diet
There is a significant degree of dietary diversity across and within the various Southeast Asian countries. This is due to a myriad of factors such as a degree of past and present foreign influence, a history of maritime trade, and an abundance of local ingredients available in the region. Social stratification coupled with the many distinct ethnicities, cultures, religions further complicate meal practices by impacting the choice of foods, the structure of meals, as well as the patterns of eating behaviour. This level of variability can make it difficult for consumption patterns to be accurately defined and may reduce the effectiveness of population-wide nutrition surveillance.
  • 5.2K
  • 30 Oct 2020
Topic Review
Mountain Man
A mountain man is an explorer who lives in the wilderness. Mountain men were most common in the North American Rocky Mountains from about 1810 through to the 1880s (with a peak population in the early 1840s). They were instrumental in opening up the various Emigrant Trails (widened into wagon roads) allowing Americans in the east to settle the new territories of the far west by organized wagon trains traveling over roads explored and in many cases, physically improved by the mountain men and the big fur companies originally to serve the mule train based inland fur trade. They arose in a natural geographic and economic expansion driven by the lucrative earnings available in the North American fur trade, in the wake of the various 1806–07 published accounts of the Lewis and Clark expeditions' (1803–1806) findings about the Rockies and the (ownership-disputed) Oregon Country where they flourished economically for over three decades. By the time two new international treaties in early 1846 and early 1848 officially settled new western coastal territories in the United States and spurred a large upsurge in migration, the days of mountain men making a good living by fur trapping had largely ended. This was partly because the fur industry was failing due to reduced demand and over trapping. With the rise of the silk trade and quick collapse of the North American beaver-based fur trade in the later 1830s–1840s, many of the mountain men settled into jobs as Army Scouts or wagon train guides or settled throughout the lands which they had helped open up. Others, like William Sublette, opened up fort-trading posts along the Oregon Trail to service the remnant fur trade and the settlers heading west.
  • 5.2K
  • 11 Nov 2022
Topic Review
Adaptation of Seed Germination
Environmental conditions are the basis of plant reproduction and are the critical factors controlling seed dormancy and germination. Global climate change is currently affecting environmental conditions and changing the reproduction of plants from seeds. Disturbances in germination will cause disturbances in the diversity of plant communities. Models developed for climate change scenarios show that some species will face a significant decrease in suitable habitat area. Dormancy is an adaptive mechanism that affects the probability of survival of a species. The ability of seeds of many plant species to survive until dormancy recedes and meet the requirements for germination is an adaptive strategy that can act as a buffer against the negative effects of environmental heterogeneity. The influence of temperature and humidity on seed dormancy status underlines the need to understand how changing environmental conditions will affect seed germination patterns. 
  • 5.2K
  • 06 Feb 2021
Topic Review
Loopholes in Bell Tests
In Bell tests, there may be problems of experimental design or set-up that affect the validity of the experimental findings. These problems are often referred to as "loopholes". See the article on Bell's theorem for the theoretical background to these experimental efforts (see also John Stewart Bell). The purpose of the experiment is to test whether nature is best described using a local hidden-variable theory or by the quantum entanglement theory of quantum mechanics. The "detection efficiency", or "fair sampling" problem is the most prevalent loophole in optical experiments. Another loophole that has more often been addressed is that of communication, i.e. locality. There is also the "disjoint measurement" loophole which entails multiple samples used to obtain correlations as compared to "joint measurement" where a single sample is used to obtain all correlations used in an inequality. To date, no test has simultaneously closed all loopholes. Ronald Hanson of the Delft University of Technology claims the first Bell experiment that closes both the detection and the communication loopholes. (This was not an optical experiment in the sense discussed below; the entangled degrees of freedom were electron spins rather than photon polarization.) Nevertheless, correlations of classical optical fields also violate Bell's inequality. In some experiments there may be additional defects that make "local realist" explanations of Bell test violations possible; these are briefly described below. Many modern experiments are directed at detecting quantum entanglement rather than ruling out local hidden-variable theories, and these tasks are different since the former accepts quantum mechanics at the outset (no entanglement without quantum mechanics). This is regularly done using Bell's theorem, but in this situation the theorem is used as an entanglement witness, a dividing line between entangled quantum states and separable quantum states, and is as such not as sensitive to the problems described here. In October 2015, scientists from the Kavli Institute of Nanoscience reported that the quantum nonlocality phenomenon is supported at the 96% confidence level based on a "loophole-free Bell test" study. These results were confirmed by two studies with statistical significance over 5 standard deviations which were published in December 2015. However, Alain Aspect writes that No experiment can be said to be totally loophole-free.
  • 5.2K
  • 31 Oct 2022
Topic Review
Fatty Acid Synthase
Fatty acid synthase is a multi-enzyme protein that involves in fatty acid synthesis. It's main function is to synthesise palmitate, a 16-carbon long chain saturated fatty acid from acetyl-CoA and malonyl-CoA, in the presence of NADPH.
  • 5.2K
  • 01 Sep 2020
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