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Topic Review
Social Change
Social change refers to the transformation of societal structures, institutions, and behaviors over time. It involves shifts in values, norms, and practices that impact the way individuals and groups interact, ultimately influencing the broader dynamics of a society. Social change can result from various factors, including technological advancements, cultural evolution, political movements, and economic developments.
  • 5.8K
  • 26 Jan 2024
Topic Review
Voyeurism
Voyeurism is the sexual interest in or practice of watching other people engaged in intimate behaviors, such as undressing, sexual activity, or other actions usually considered to be of a private nature. The term comes from the French voir which means "to see". A male voyeur is commonly labelled as "Peeping Tom" or a "Jags", a term which originates from the Lady Godiva legend. However, that term is usually applied to a male who observes somebody secretly and, generally, not in a public space. The American Psychiatric Association has classified certain voyeuristic fantasies, urges and behaviour patterns as a paraphilia in the Diagnostic and Statistical Manual (DSM-IV) if the person has acted on these urges, or the sexual urges or fantasies cause marked distress or interpersonal difficulty. It is described as a disorder of sexual preference in the ICD-10. The DSM-IV defines voyeurism as the act of looking at "unsuspecting individuals, usually strangers, who are naked, in the process of disrobing, or engaging in sexual activity". The diagnosis would not be given to people who experience typical sexual arousal simply by seeing nudity or sexual activity. In order to be diagnosed with voyeuristic disorder the symptoms must persist for over six months and the person in question must be over the age of 18.
  • 5.8K
  • 11 Nov 2022
Topic Review
Catalyst Design via Colloidal Synthesis
Supported nanoparticles are commonly applied in heterogeneous catalysis. The catalytic performance of these solid catalysts is, for a given support, dependent on the nanoparticle size, shape, and composition, thus necessitating synthesis techniques that allow for preparing these materials with fine control over those properties. Such control can be exploited to deconvolute their effects on the catalyst’s performance, which is the basis for knowledge-driven catalyst design. In this regard, bottom-up synthesis procedures based on colloidal chemistry have proven successful in achieving the desired level of control for a variety of fundamental studies. This article aims to give an overview of recent progress made in this synthesis technique for the application of controlled catalytic materials in gas-phase catalysis. The focus goes to mono- and bimetallic materials, as well as to recent efforts in enhancing their performance by embedding colloidal templates in porous oxide phases.
  • 5.8K
  • 12 May 2021
Topic Review
Deep Learning Based Speech Synthesis
Speech synthesis, also known as text-to-speech (TTS), has attracted increasingly more attention. Recent advances on speech synthesis are overwhelmingly contributed by deep learning or even end-to-end techniques which have been utilized to enhance a wide range of application scenarios such as intelligent speech interaction, chatbot or conversational artificial intelligence (AI). For speech synthesis, deep learning based techniques can leverage a large scale of <text, speech> pairs to learn effective feature representations to bridge the gap between text and speech, thus better characterizing the properties of events.
  • 5.8K
  • 08 Apr 2021
Topic Review Peer Reviewed
Ethical Issues in Researching Higher Education Teaching and Learning
Higher education here is taken to be education beyond school level: often at an institution (a university) that has degree-awarding powers, though some programmes may lead to a diploma, certificate or other award or qualification. Nomenclature around “research” in the associated teaching and learning is contested: professional enquiry, scholarship of teaching and learning, pedagogical research… are some of the terms used. Authors discuss and distinguish such terms. An ethical issue is a circumstance in which a moral conflict arises or is implicit and should be resolved in a morally acceptable way. These include privacy, informed consent, insider research and power relationships within higher education research; there are also fluid challenges around the use of digital contributions. Authors present a narrative exegesis of work in the associated areas, which authors argue will be of use to universities promoting such research, and of particular interest to two groups of academics wishing to systematically develop their practice in ways that contribute to the field: those on teaching-only contracts, who would also demonstrate their research credentials; and researchers from non-education-cognate fields. Authors identify directions for further work.
  • 5.8K
  • 24 Jul 2024
Topic Review
Transnational Marriage
An international marriage, or transnational marriage, is a marriage between two people from different countries. A variety of special issues arise in marriages between people from different countries, including those related to citizenship and culture, which add complexity and challenges to these kinds of relationships. Culture and language differences are often encountered as obstacles, although there are exceptions. Where ethnic groups are divided between multiple sovereign states (irredentism or stateless nations) or places which once shared common citizenship are separated by borders of newly independent nations (decolonisation), transnational marriages do not necessarily imply different cultures. In an age of increasing globalization, where a growing number of people have ties to networks of people and places across the globe, rather than to a current geographic location, people are increasingly marrying across national boundaries. Transnational marriage is a by-product of the movement and migration of people.
  • 5.8K
  • 29 Sep 2022
Topic Review
Timeline of Epochs in Cosmology
The timeline of cosmological epochs outlines the formation and subsequent evolution of the Universe from the Big Bang (13.799 ± 0.021 billion years ago) to the present day. An epoch is a moment in time from which nature or situations change to such a degree that it marks the beginning of a new era or age. Times on this list are measured from the moment of the Big Bang.
  • 5.7K
  • 21 Nov 2022
Topic Review
Modulators in Silicon Photonics
Silicon optical technology extends beyond just lasers, offering photonic components such as, modulators, photodetectors (PDs), splitters, (de)multiplexers, and filters.
  • 5.7K
  • 08 Feb 2022
Topic Review
CubeSat Missions and Their Antenna Designs
CubeSats are a class of miniaturized satellites that have become increasingly popular in academia and among hobbyists due to their short development time and low fabrication cost. Their compact size, lightweight characteristics, and ability to form a swarm enables them to communicate directly with one another to inspire new ideas on space exploration, space-based measurements, and implementation of the latest technology. CubeSat missions require specific antenna designs in order to achieve optimal performance and ensure mission success. Over the past, a plethora of antenna designs have been proposed and implemented on CubeSat missions. Several challenges arise when designing CubeSat antennas such as gain, polarization, frequency selection, pointing accuracy, coverage, and deployment mechanisms.
  • 5.7K
  • 18 Jul 2022
Topic Review
Abiotic and Biotic Polymer Degradation Mechanisms
Polymer degradation is defined as an irreversible change of the chemical structure, physical properties, and visual appearance due to the chemical cleavage of the polymer’s constitutive macromolecules by one or more mechanism. More than one mechanism can simultaneously take place due to the action of external factors, and one mechanism can be more dominant than others at any time. External factors associated with the environment, such as heat, humidity, radiation, and acidic or alkaline conditions, could modify the degradation process and its rate. The degradation process can alter polymer properties such as mechanical, optical, electrical, discoloration, phase separation or delamination, erosion, cracking, and crazing. The four main abiotic mechanisms associated with polymer degradation are mechanical, thermal (or thermo-oxidative), photo (photo-oxidative), and hydrolytic (chemical) degradation, some of which can be assisted by catalysis. In addition, ozone degradation (chemical) is considered a mechanism of degradation for polymers but is less common. The biotic degradation involves the action of microorganisms by enzymatic action.
  • 5.7K
  • 27 Oct 2022
Topic Review
Leadership
Leadership is both a research area and a practical skill encompassing the ability of an individual or organization to "lead" or guide other individuals, teams, or entire organizations. Specialist literature debates various viewpoints, contrasting Eastern and Western approaches to leadership, and also (within the West) United States versus European approaches. U.S. academic environments define leadership as "a process of social influence in which a person can enlist the aid and support of others in the accomplishment of a common task". Leadership seen from a European and non-academic perspective encompasses a view of a leader who can be moved not only by communitarian goals but also, as the European researcher Daniele Trevisani sugggests, by the search for personal power. Studies of leadership have produced theories involving traits, situational interaction, function, behavior, power, vision and values, charisma, and intelligence, among others.
  • 5.7K
  • 21 Nov 2022
Topic Review
Wave Energy Marine Buoys
The power supply is usually the bottleneck for marine distributed systems such as buoys. Wave energy technologies are especially useful in this sense, as they can capture and convert the promising “native” renewable energy in the ocean (i.e., wave energy) into electricity.
  • 5.7K
  • 08 Jul 2022
Topic Review
Paleolibertarianism
Paleolibertarianism is a variety of libertarianism developed by anarcho-capitalist theorists Murray Rothbard and Llewellyn Rockwell that combines conservative cultural values and social philosophy with a libertarian opposition to government intervention.
  • 5.7K
  • 24 Oct 2022
Topic Review
Metal Sulfide Precipitation
Metal sulfide precipitation can efficiently recover several metals and metalloids from different aqueous sources, including wastewaters and hydrometallurgical solutions. 
  • 5.7K
  • 04 Jan 2022
Topic Review
Phosphate in Primary Hyperparathyroidism
Serum phosphate is crucial in the management of kidney disease, playing a major role in vascular calcification in chronic kidney failure.  In the past 20 years, the role of phosphate has been profoundly reconsidered since many other molecules have been found to play important roles in phosphate homeostasis, beyond the well-known effect of parathyroid hormone (PTH) or renal function. The advent of new insights into phosphate metabolism must urge the endocrinologist to rethink the pathophysiology of widespread disorders, such as primary hyperparathyroidism.
  • 5.7K
  • 15 Dec 2021
Topic Review
Leucine Metabolism
Leucine, an essential branched amino acid, has anti-obesity effects on glucose tolerance, lipid metabolism, and insulin sensitivity. The catabolism of Leucine is a conserved regulator of physiological aging, participating in diverse physiological and pathological processes. This topic review offers an up-to-date report on the decomposition and metabolites of leucine in mammals, as α-ketoisocaproate (KIC) and β-hydroxy-β-methylbutyrate (HMB).
  • 5.7K
  • 29 Oct 2020
Topic Review
Beta-Carotene
β-Carotene is an organic, strongly coloured red-orange pigment abundant in fungi, plants, and fruits. It is a member of the carotenes, which are terpenoids (isoprenoids), synthesized biochemically from eight isoprene units and thus having 40 carbons. Among the carotenes, β-carotene is distinguished by having beta-rings at both ends of the molecule. β-Carotene is biosynthesized from geranylgeranyl pyrophosphate. In some Mucoralean fungi, β-Carotene is a precursor to the synthesis of trisporic acid. β-Carotene is the most common form of carotene in plants. When used as a food coloring, it has the E number E160a.:119 The structure was deduced by Karrer et al. in 1930. In nature, β-carotene is a precursor (inactive form) to vitamin A via the action of beta-carotene 15,15'-monooxygenase. Isolation of β-carotene from fruits abundant in carotenoids is commonly done using column chromatography. It can also be extracted from the beta-carotene rich algae, Dunaliella salina. The separation of β-carotene from the mixture of other carotenoids is based on the polarity of a compound. β-Carotene is a non-polar compound, so it is separated with a non-polar solvent such as hexane. Being highly conjugated, it is deeply colored, and as a hydrocarbon lacking functional groups, it is very lipophilic.
  • 5.7K
  • 16 Nov 2022
Topic Review
Sugar Based Surfactants
Sugar-based surfactants are a class of surfactants derived from natural sugars, such as glucose, sucrose, and maltose. These surfactants have gained significant interest in recent years due to their biodegradability, low toxicity, and high compatibility with biological systems. Sugar-based surfactants are classified into two main groups: alkyl polyglucosides (APGs) and saccharide fatty acid esters (SFAEs). APGs are produced by reacting a fatty alcohol with glucose, while SFAEs are produced by esterifying a sugar molecule with a fatty acid. APGs have excellent cleaning and foaming properties and are used in a variety of personal care and household products, including shampoos, body washes, and dishwashing detergents. SFAEs are mainly used in the food industry as emulsifiers and stabilizers. One of the main advantages of sugar-based surfactants is their biodegradability, which means that they break down into harmless substances when exposed to environmental conditions such as sunlight, water, and microorganisms. This makes them an attractive alternative to synthetic surfactants, which can persist in the environment for a long time and have negative impacts on ecosystems.
  • 5.7K
  • 24 Mar 2023
Topic Review
Sarcopterygii
Sarcopterygii (/ˌsɑːrkɒptəˈrɪdʒi.aɪ/; from grc σάρξ (sárx) 'flesh', and πτέρυξ (ptérux) 'wing, fins')—sometimes considered synonymous with Crossopterygii (from grc κροσσός (krossós) 'fringe')—is a taxon (traditionally a class or subclass) of the bony fishes whose members are known as lobe-finned fishes. The group Tetrapoda, a superclass including amphibians, reptiles (including dinosaurs and therefore birds), and mammals, evolved from certain sarcopterygians; under a cladistic view, tetrapods are themselves considered a group within Sarcopterygii. The known extant non-tetrapod sarcopterygians include two species of coelacanths and six species of lungfishes.
  • 5.7K
  • 27 Oct 2022
Topic Review
Biostimulants
Biostimulants represent a promising type of environment-friendly formulation based on natural products that are frequently used exogenously to enhance abiotic stress tolerance. There is no specific definition of biostimulants yet, despite their regulatory functions in plant growth and development. Biostimulants originate from natural sources and can be effectively categorized into the following four prime groups, namely, acids, microbes, plant-derived bioactive substances, and others.
  • 5.7K
  • 08 Apr 2022
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