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Topic Review
Schweizer 300
The Schweizer RSG 300 series (formerly Sikorsky S300, Hughes 300 and Schweizer 300) family of light utility helicopters was originally produced by Hughes Helicopters, as a development of the Hughes 269. Later manufactured by Schweizer Aircraft, the basic design has been in production for almost 50 years. The single, three-bladed main rotor and piston-powered S-300 is mostly used as a cost-effective platform for training and agriculture.
  • 3.0K
  • 08 Nov 2022
Topic Review
E-Cigarette Impact on Reproductive Health
Electronic cigarettes (e-cigarettes) are often considered a “safe substitute” for conventional cigarette cessation. The composition of the fluid is not always clearly defined and shows a large variation within brands and manufacturers. More than 80 compounds were detected in liquids and aerosols. E-cigarettes contain nicotine, and the addition of flavorings increases the toxicity of e-cigarette vapour in a significant manner. The heat generated by the e-cigarette leads to the oxidation and decomposition of its components, eventually forming harmful constituents in the inhaled vapour. The effects of these toxicants on male and female reproduction are well established in conventional cigarette smokers. 
  • 3.0K
  • 27 Mar 2023
Topic Review
Electrodermal Activity Data Collection
The electrodermal activity (EDA) signal is an electrical manifestation of the sympathetic innervation of the sweat glands. EDA has a history in psychophysiological (including emotional or cognitive stress) research since 1879, but it was not until recent years that researchers began using EDA for pathophysiological applications like the assessment of fatigue, pain, sleepiness, exercise recovery, diagnosis of epilepsy, neuropathies, depression, and so forth. The advent of new devices and applications for EDA has increased the development of novel signal processing techniques, creating a growing pool of measures derived mathematically from the EDA. For many years, simply computing the mean of EDA values over a period was used to assess arousal. Much later, researchers found that EDA contains information not only in the slow changes (tonic component) that the mean value represents, but also in the rapid or phasic changes of the signal. The techniques that have ensued have intended to provide a more sophisticated analysis of EDA, beyond the traditional tonic/phasic decomposition of the signal. With many researchers from the social sciences, engineering, medicine, and other areas recently working with EDA, it is timely to summarize and review the recent developments and provide an updated and synthesized framework for all researchers interested in incorporating EDA into their research.
  • 3.0K
  • 30 Oct 2020
Topic Review
Brick (Electronics)
The word "brick", when used in reference to consumer electronics, describes an electronic device such as a mobile device, game console, or router that, due to corrupted firmware, a hardware problem, or other damage, can no longer function, and thus is "bricked". The device becomes as technologically useful as a brick, hence the name.
  • 3.0K
  • 19 Oct 2022
Topic Review
Forensic Dentistry
Forensic dentistry or forensic odontology involves handling, examination and evaluation of dental evidence in criminal justice cases. Forensic dentists are involved in assisting investigative agencies to identify recovered human remains in addition to the identification of whole or fragmented bodies. Forensic dentists have also been known to use their investigative techniques to identify burn victims by using the victims previous dental records. Forensic dentists may also be asked to assist in determining age, race, occupation, previous dental history and socioeconomic status of unidentified human beings. The evidence that may be derived from teeth is the age (in children) and identification of the person to whom the teeth belong. This is done using dental records including radiographs, ante-mortem (prior to death) and post-mortem (after death) photographs and DNA. Another type of evidence is that of bite marks, left on either the victim (by the attacker), the perpetrator (from the victim of an attack), or on an object found at the crime scene. Bite mark analysis has been condemned by several scientific bodies, such as the National Academy of Sciences (NAS), the President's Council of Advisors on Science and Technology (PCAST), and the Texas Forensic Science Commission. No scientific studies or evidence substantiate that bite marks can demonstrate sufficient detail for positive identification. There are numerous instances where experts diverge widely in their evaluations of the same bite mark evidence.
  • 3.0K
  • 18 Nov 2022
Topic Review
Reflective Façades
Reflection and transparency are two valuable properties associated with the use of glass as an architectural material. While proponents of modernism favored transparency over reflection, whether in its physical or conceptual implications, to justify the designs of façades of Modernist buildings and in architectural criticism, contemporary architects are revisiting the neglected trait of ‘reflection’.
  • 3.0K
  • 14 Nov 2023
Topic Review
Smartphone Addiction and Associated Health Outcomes
Smartphone addiction (SA) is generally conceptualized as a behavioral addiction including mood tolerance, salience, withdrawal, modification, conflict, and relapse. Literature suggests that there are associations between SA and mental health, physical health, and neurological problems. Furthermore, tolerance, salience, withdrawal, and cravingshave been associated with excessive smartphone use.
  • 3.0K
  • 09 Dec 2021
Topic Review
Grihastha
Grihastha (Sanskrit: gr̥hastha) literally means "being in and occupied with home, family" or "householder". It refers to the second phase of an individual's life in a four age-based stages of the Hindu ashram system. It follows celibacy (bachelor student) life stage, and embodies a married life, with the duties of maintaining a home, raising a family, educating one's children, and leading a family-centred and a dharmic social life. This stage of Ashrama is conceptually followed by Vanaprastha (forest dweller, retired) and Sannyasa (renunciation). Combined with other three life stages, Hindu philosophy considers these stages as a facet of Dharma concept, something essential to completing the full development of a human being and fulfilling all the needs of the individual and society. Ancient and medieval era texts of Hinduism consider Grihastha stage as the most important of all stages in sociological context, as human beings in this stage not only pursue a virtuous life, they produce food and wealth that sustains people in other stages of life, as well as the offspring that continues mankind. The householder stage is also considered in Indian philosophy as one where the most intense physical, sexual, emotional, occupational, social and material attachments exist in a human being's life. In Indian traditions, Grihastha stage of life is a recommendation, but not a requirement. Any Brahmacharya may, if he or she wants, skip householder and retirement stage, go straight to Sannyasa stage of life, thereby renouncing worldly and materialistic pursuits and dedicating their lives to spiritual pursuits.
  • 3.0K
  • 11 Oct 2022
Topic Review
Synthesis of the Coumarin Core
Coumarin compounds are attractive organic compounds with many practical applications. Among them there are compounds with biological activity, pharmaceuticals, agrochemicals, dyes, and optoelectronic materials. For this reason, enormous and continuous attempts were made to develop new synthetic pathways and protocols to facilitate the key cyclization reaction of heterocyclic ring and its regioselective functionalization. Of the numerous proposed reactions for the preparation of coumarins, those based on transition metal catalysts have been frequently used recently. Such processes as intramolecular and intermolecular hydroarylation of alkenes or alkynes can be mentioned among the most effective reactions proceeding via the activation of the C–H bond. Knowledge about the mechanistic foundations of catalytic processes seems to be of significant importance in order to improve them and simplify the conditions. Direct functionalization of the coumarin skeleton seems to be one of the more difficult tasks in recent times.
  • 3.0K
  • 23 Mar 2022
Topic Review
Impact of Tritium on Living Organisms
Tritium is a byproduct of many radiochemical reactions in the nuclear industry, and its effects on aquatic organisms, particularly low-dose effects, deserve special attention. The low-dose effects of tritium on aquatic microbiota have been intensively studied using luminous marine bacteria as model microorganisms. Low-dose physiological activation has been demonstrated and explained by the signaling role of reactive oxygen species through the “bystander effect” in bacterial suspensions. The activation of microbial functions in natural reservoirs by low tritium concentrations can cause unpredictable changes in food chains and imbalances in the natural equilibrium. The incorporation of tritium from the free form into organically bound compounds mainly occurs in the dark and at a temperature of 25 °C. When tritium is ingested by marine animals, up to 56% of tritium is accumulated in the muscle tissue and up to 36% in the liver. About 50% of tritium in the liver is bound in non-exchangeable forms. Human ingestion of water and food products contaminated with background levels of tritium does not significantly contribute to the total dose load on the human body. 
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  • 22 Apr 2022
Topic Review
Diagnosis of Postural Tachycardia Syndrome and vasovagal Syncope
In children, vasovagal syncope and postural tachycardia syndrome constitute the major types of orthostatic intolerance. The clinical characteristics of postural tachycardia syndrome and vasovagal syncope are similar but their treatments differ. Therefore, their differential diagnosis is important to guide the correct treatment. Children suffering from vasovagal syncope or postural tachycardia syndrome might be treated using water, β-blockers, salt, or midodrine. However, the effificacy of the drugs varies. Biomarkers or certain hemodynamic parameters that can predict the treatment effects of individualized treatment for POTS or VVS have been used.
  • 3.0K
  • 08 Jul 2022
Topic Review
Declaration of Nullity
Template:Canon Law In the Catholic Church, a declaration of nullity, commonly called an annulment and less commonly a decree of nullity, is a judgment on the part of an ecclesiastical tribunal determining that a marriage was invalidly contracted or, less frequently, a judgment determining that ordination was invalidly conferred. A matrimonial nullity trial, governed by canon law, is a judicial process whereby a canonical tribunal determines whether the marriage was void at its inception (ab initio). A "Declaration of Nullity" is not the dissolution of an existing marriage (as is a dispensation from a marriage ratum sed non consummatum and an "annulment" in civil law), but rather a determination that consent was never validly exchanged due to a failure to meet the requirements to enter validly into matrimony and thus a marriage never existed. The Catholic Church teaches that, in a true marriage, one man and one woman become "one flesh" before the eyes of God. Various impediments can render a person unable to validly contract a marriage. Besides impediments, marriage consent can be rendered null due to invalidating factors such as simulation or deceit, or to psychological incapacity. In 2015, the process for declaring matrimonial nullity was amended by the matrimonial nullity trial reforms of Pope Francis, the broadest reforms to matrimonial nullity law in 300 years. Prior to the reforms, a declaration of nullity could only be effective if it had been so declared by two tribunals at different levels of jurisdiction. If the lower courts (First and Second Instance) were not in agreement, the case went automatically to the Roman Rota for final decision one way or another.
  • 3.0K
  • 09 Oct 2022
Topic Review
Kidney Failure after Liver Transplantation
One-third of patients with cirrhosis present kidney failure (AKI and CKD). It has multifactorial causes and a harmful effect on morbidity and mortality before and after liver transplantation. Kidney function does not improve in all patients after liver transplantation, and liver transplant recipients are at a high risk of developing chronic kidney disease. The causes of renal dysfunction can be divided into three groups: pre-operative, perioperative and post-operative factors.
  • 2.9K
  • 22 Sep 2021
Topic Review
Drug–Food Interactions of DOACs
In recent years direct oral anticoagulants (DOACs) have become the anticoagulant treatment of choice. DOACs were initially considered drugs with no significant food interactions; however, clinical observations from daily practice have proved otherwise as interactions with food ingredients have been reported. Food, dietary supplements or herbs may contain substances that, when administered concomitantly with DOACs, can potentially affect the plasma concentration of the drugs. 
  • 2.9K
  • 27 Aug 2021
Topic Review
Proteomics for Studying Antibiotic Action
To design more efficient treatments against bacterial infections, detailed knowledge about the bacterial response to the commonly used antibiotics is required. Proteomics is a well-suited and powerful tool to study molecular response to antimicrobial compounds. Bacterial response profiling from system-level investigations could increase our understanding of bacterial adaptation, the mechanisms behind antibiotic resistance and tolerance development.
  • 2.9K
  • 03 Nov 2020
Topic Review
Fabric Phase Sorptive Extraction
Fabric phase sorptive extraction (FPSE) is an evolutionary sample preparation technique which was introduced in 2014, delivering all green analytical chemistry (GAC) requirements by implementing a natural or synthetic permeable and flexible fabric substrate to host a chemically coated sol–gel organic–inorganic hybrid sorbent in the form of an ultra-thin coating. This construction results in a versatile, fast, and sensitive micro-extraction device. The user-friendly FPSE membrane allows direct extraction of analytes with no sample modification, thus eliminating/minimizing the sample pre-treatment steps, which are not only time consuming, but are also considered the primary source of major analyte loss. Sol–gel sorbent-coated FPSE membranes possess high chemical, solvent, and thermal stability due to the strong covalent bonding between the fabric substrate and the sol–gel sorbent coating. Subsequent to the extraction on FPSE membrane, a wide range of organic solvents can be used in a small volume to exhaustively back-extract the analytes after FPSE process, leading to a high preconcentration factor. In most cases, no solvent evaporation and sample reconstitution are necessary. 
  • 2.9K
  • 08 Feb 2021
Topic Review
Indoor Air Pollution in Developing Nations
Indoor air pollution in developing nations is a significant form of indoor air pollution (IAP) that is little known to those in the developed world. Three billion people in developing countries across the globe rely on biomass, in the form of wood, charcoal, dung, and crop residue, as their domestic cooking fuel. Since much of the cooking is carried out indoors in environments that lack proper ventilation, millions of people, primarily poor women and children face serious health risks. The major sources of indoor air pollution include combustion and building materials. Globally, 4.3 million deaths were attributed to exposure to IAP in developing countries in 2012, almost all in low and middle-income countries. The South East Asian and Western Pacific regions bear most of the burden with 1.69 and 1.62 million deaths, respectively. Almost 600,000 deaths occur in Africa, 200,000 in the Eastern Mediterranean region, 99,000 in Europe and 81,000 in the Americas. The remaining 19,000 deaths occur in high-income countries. Even though the rate of dependence on biomass fuel is declining, this dwindling resource will not keep up with population growth which could ultimately put environments at even greater risk. Over the past several decades, there have been numerous studies investigating the air pollution generated by traditional household solid fuel combustion for space heating, lighting, and cooking in developing countries. It is now well established that, throughout much of the developing world, indoor burning of solid fuels (biomass, coal, etc.) by inefficient, often insufficiently vented, combustion devices results in elevated exposure to household air pollutants. This is due to the poor combustion efficiency of the combustion devices and the elevated nature of the emissions. In addition, they are often released directly into living areas. Smoke from traditional household solid fuel combustion commonly contains a range of incomplete combustion products, including both fine and coarse particulate matter (e.g., PM2.5, PM10), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and a variety of organic air pollutants (e.g., formaldehyde, 1,3-butadiene, benzene, acetaldehyde, acrolein, phenols, pyrene, benzopyrene, benzo(a)pyrene, dibenzopyrenes, dibenzocarbazoles, and cresols). In a typical solid fuel stove, about 6–20% of the solid fuel is converted into toxic emissions (by mass). The exact quantity and relative composition is determined by factors such as the fuel type and moisture content, stove type and operation influencing the amount. While many pollutants can evolve, most measurements have been focused on breathing-zone exposure levels of particulate matter (PM) and carbon monoxide (CO), which are the main products of incomplete combustion and are considered to pose the greatest health risks. Indoor PM2.5 exposure levels have been consistently reported to be in the range of hundreds to thousands of micrograms per cubic meter (μg/m3). Similarly, CO exposure levels have been measured to be as high as hundreds to greater than 1000 milligrams per cubic meter (mg/m3). A recent study of 163 households in two rural Chinese counties reported geometric mean indoor PM2.5 concentrations of 276 μg/m3 (combinations of different plant materials, including wood, tobacco stems, and corncobs), 327 μg/m3 (wood), 144 μg/m3 (smoky coal), and 96 μg/m3 (smokeless coal) for homes using a variety of different fuel types and stove configurations (e.g., vented, unvented, portable, fire pit, mixed ventilation stove).
  • 2.9K
  • 22 Nov 2022
Topic Review
Nucleic Acid
Nucleic acids are the biopolymers, or small biomolecules, essential to all known forms of life. The term nucleic acid is the overall name for DNA and RNA. They are composed of nucleotides, which are the monomers made of three components: a 5-carbon sugar, a phosphate group and a nitrogenous base. If the sugar is a compound ribose, the polymer is RNA (ribonucleic acid); if the sugar is derived from ribose as deoxyribose, the polymer is DNA (deoxyribonucleic acid). Nucleic acids are the most important of all biomolecules. They are found in abundance in all living things, where they function to create and encode and then store information in the nucleus of every living cell of every life-form organism on Earth. In turn, they function to transmit and express that information inside and outside the cell nucleus—to the interior operations of the cell and ultimately to the next generation of each living organism. The encoded information is contained and conveyed via the nucleic acid sequence, which provides the 'ladder-step' ordering of nucleotides within the molecules of RNA and DNA. Strings of nucleotides are bonded to form helical backbones—typically, one for RNA, two for DNA—and assembled into chains of base-pairs selected from the five primary, or canonical, nucleobases, which are: adenine, cytosine, guanine, thymine, and uracil; note, thymine occurs only in DNA and uracil only in RNA. Using amino acids and the process known as protein synthesis, the specific sequencing in DNA of these nucleobase-pairs enables storing and transmitting coded instructions as genes. In RNA, base-pair sequencing provides for manufacturing new proteins that determine the frames and parts and most chemical processes of all life forms.
  • 2.9K
  • 28 Nov 2022
Topic Review Peer Reviewed
Artificial Intelligence in Special Education
This entry examines the growing role of artificial intelligence (AI) in special education. The authors discuss applications of AI in the field, including its uses for personalized learning, adaptive technologies, teacher support, and AI’s potential to address issues related to student accessibility and engagement. The entry draws on recent syntheses of literature, highlighting studies that reveal AI’s capacity to improve educational outcomes for students with disabilities, mitigate teacher workload, and foster inclusion. Despite these promising developments, the authors address ethical considerations, potential biases, and privacy concerns surrounding the use of AI, as well as the need for high-quality research that validates AI’s effectiveness in special education. The authors conclude that while AI can offer substantial support, it should be integrated thoughtfully, guided by empirical research, and accompanied by skilled professional oversight to ensure that it truly benefits students with disabilities.
  • 2.9K
  • 15 Jan 2025
Topic Review
Water Resource Management
Water resource management is the activity of planning, developing, distributing and managing the optimum use of water resources. It is an aspect of water cycle management. Water is essential for our survival. The field of water resources management will have to continue to adapt to the current and future issues facing the allocation of water. With the growing uncertainties of global climate change and the long-term impacts of past management actions, this decision-making will be even more difficult. It is likely that ongoing climate change will lead to situations that have not been encountered. As a result, alternative management strategies, including participatory approaches and adaptive capacity are increasingly being used to strengthen water decision-making. Ideally, water resource management planning has regard to all the competing demands for water and seeks to allocate water on an equitable basis to satisfy all uses and demands. As with other resource management, this is rarely possible in practice so decision-makers must prioritise issues of sustainability, equity and factor optimisation (in that order!) to achieve acceptable outcomes. One of the biggest concerns for our water-based resources in the future is the sustainability of the current and future water resource allocation. As water becomes scarce, the importance of water management grows vastly—finding a balance between humans' needs and the essential step of water resources sustainability in the environment.
  • 2.9K
  • 03 Nov 2022
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