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Topic Review
Smart City 4.0 Development
The concept of the Smart City emerged as an effect of the research into smart urban environments. The term ‘smart city’ is understood as a city having a certain intellectual ability, which refers to innovative sociotechnical and socioeconomic aspects of growth. It has six dimensions: a smart economy, smart mobility, smart environment, smart people, smart living, and smart governance. Smart Cities 4.0 remain hyper-connected, as they use technology, data and engagement of citizens, but they use it to achieve the objectives of sustainable development.
  • 5.9K
  • 21 Mar 2022
Topic Review
Conventional Liposomal Formulation Methods
Liposome-based drug delivery systems are nanosized spherical lipid bilayer carriers that can encapsulate a broad range of small drug molecules (hydrophilic and hydrophobic drugs) and large drug molecules (peptides, proteins, and nucleic acids). They have unique characteristics, such as a self-assembling bilayer vesicular structure. There are various methods used in the preparation of lipid-based nanocarriers such as liposomes. The method of preparation affects critical parameters such as size of vesicle and size distribution, permeability, lamellarity, and entrapment efficiency. Entrapment of compounds is performed by two main techniques; passive loading where drug entrapment occurs during the liposome formation, and active loading where drug entrapment is after the liposome formation.
  • 5.9K
  • 15 May 2023
Topic Review
Areca nut
Scientific name:  Areca catechu L. Family: Arecaceae Centre of origin: South-East Asia Common name: kamuhu, adakka, adike, Pinang palm, Betel palm, Areca palm, Supari, Kaunga The generic name is derived from the common name used by the people of the Malabar Coast in southwestern India.
  • 5.9K
  • 16 Feb 2022
Topic Review
Nanodiamonds Synthesis Techniques
The "state-of-the-art" of the nanodiamonds synthesis techniques is reviewed with emphasis on the more recent one involving pulsed laser ablation. Production of NV centers inside the nanodiamonds and  post-production cleaning processes to remove residual graphite layers are also described.
  • 5.9K
  • 27 Oct 2020
Topic Review
People's Party of Canada
The People's Party of Canada (PPC; French: Parti populaire du Canada or simply People's Party) is a federal political party in Canada. The party was formed by Maxime Bernier in September 2018, shortly after his resignation from the Conservative Party of Canada. Bernier, the Member of Parliament for Beauce and a former cabinet minister, was the party's only MP from its founding in 2018 to his defeat in the 2019 Canadian federal election. Bernier had represented the Quebec riding in Parliament from 2006, when he was elected as a Conservative. The party has been referred to as conservative, libertarian, populist,, and classical liberal, while being seen on the right-wing to far-right of the traditional left-right political spectrum. The PPC formed electoral district associations (EDAs) in all of Canada's 338 ridings and ran a full slate of candidates in the 2019 federal election, but no candidate was elected under its banner and Bernier lost his bid for personal re-election in Beauce.
  • 5.9K
  • 22 Nov 2022
Topic Review
Sexual Robots
The area of human-robot interaction (HRI), particularly concerning sexual robots, has begun to attract interest in various social issues, such as emotions, ethics, philosophy, and psychology. These new relationships between sexual robots and humans have also awakened the interest of the media, the industry, and the maker world since with a 3D printer, it is already possible to create a sexual robot. Society has begun to consider the idea of having sex with robots, and there is the belief that this will be normal in the future. Although there is still no scientific evidence of its therapeutic benefits, many think it can help treat sexual dysfunctions or even help decrease women’s sexual exploitation. Like sex toys, some experts consider sexual robots (or sexbots) to be the future of sex relationships potentially. 
  • 5.9K
  • 11 Jan 2021
Topic Review
Compartmental Models in Epidemiology
Compartmental models are a very general modelling technique. They are often applied to the mathematical modelling of infectious diseases. The population is assigned to compartments with labels – for example, S, I, or R, (Susceptible, Infectious, or Recovered). People may progress between compartments. The order of the labels usually shows the flow patterns between the compartments; for example SEIS means susceptible, exposed, infectious, then susceptible again. The origin of such models is the early 20th century, with important works being that of Ross in 1916, Ross and Hudson in 1917, Kermack and McKendrick in 1927 and Kendall in 1956 The models are most often run with ordinary differential equations (which are deterministic), but can also be used with a stochastic (random) framework, which is more realistic but much more complicated to analyze. Models try to predict things such as how a disease spreads, or the total number infected, or the duration of an epidemic, and to estimate various epidemiological parameters such as the reproductive number. Such models can show how different public health interventions may affect the outcome of the epidemic, e.g., what the most efficient technique is for issuing a limited number of vaccines in a given population.
  • 5.9K
  • 02 Dec 2022
Topic Review
Convergent Evolution
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last common ancestor of those groups. The cladistic term for the same phenomenon is homoplasy. The recurrent evolution of flight is a classic example, as flying insects, birds, pterosaurs, and bats have independently evolved the useful capacity of flight. Functionally similar features that have arisen through convergent evolution are analogous, whereas homologous structures or traits have a common origin but can have dissimilar functions. Bird, bat, and pterosaur wings are analogous structures, but their forelimbs are homologous, sharing an ancestral state despite serving different functions. The opposite of convergence is divergent evolution, where related species evolve different traits. Convergent evolution is similar to parallel evolution, which occurs when two independent species evolve in the same direction and thus independently acquire similar characteristics; for instance, gliding frogs have evolved in parallel from multiple types of tree frog. Many instances of convergent evolution are known in plants, including the repeated development of C4 photosynthesis, seed dispersal by fleshy fruits adapted to be eaten by animals, and carnivory.
  • 5.9K
  • 24 Oct 2022
Topic Review
Colorants in Water and Toxicity
Dyes (colorants) are used in many industrial applications, and have become vital to the industrial production infrastructure. However,  effluents of some dyeing industries contain toxic chemicals, which are detrimental to both the environment and human health. Therefore,  wastewater containing dyes must be properly treated before discharging to surrounding water bodies, and this paper summarises that the most effective current method of effluent treatment for dye industries is adsorption using Biochar.
  • 5.9K
  • 08 Feb 2021
Topic Review
List of Aircraft (P)
This is a list of aircraft in alphabetical order beginning with 'P'.
  • 5.9K
  • 19 Oct 2022
Topic Review
Temporal Envelope and Fine Structure
Temporal envelope (ENV) and temporal fine structure (TFS) are changes in the amplitude and frequency of sound perceived by humans over time. These temporal changes are responsible for several aspects of auditory perception, including loudness, pitch and timbre perception and spatial hearing. Complex sounds such as speech or music are decomposed by the peripheral auditory system of humans into narrow frequency bands. The resulting narrow-band signals convey information at different time scales ranging from less than one millisecond to hundreds of milliseconds. A dichotomy between slow "temporal envelope" cues and faster "temporal fine structure" cues has been proposed to study several aspects of auditory perception (e.g., loudness, pitch and timbre perception, auditory scene analysis, sound localization) at two distinct time scales in each frequency band. Over the last decades, a wealth of psychophysical, electrophysiological and computational studies based on this envelope/fine-structure dichotomy have examined the role of these temporal cues in sound identification and communication, how these temporal cues are processed by the peripheral and central auditory system, and the effects of aging and cochlear damage on temporal auditory processing. Although the envelope/fine-structure dichotomy has been debated and questions remain as to how temporal fine structure cues are actually encoded in the auditory system, these studies have led to a range of applications in various fields including speech and audio processing, clinical audiology and rehabilitation of sensorineural hearing loss via hearing aids or cochlear implants.
  • 5.9K
  • 12 Oct 2022
Topic Review
Trinitarianism in the Church Fathers
Whether the earliest Church Fathers believed in the Trinity or not is a subject for debate. Some of the evidence used to support an early belief in the Trinity are triadic statements (referring to the Father, Son and Holy Spirit) from the New Testament and the Church Fathers. The view that the Son was 'of the essence of the Father, God of God...very God of very God' was formally ratified at the First Council of Nicaea in 325 AD. The Holy Spirit was included at the First Council of Constantinople (381 AD), where the relationship between the Father, Son and Holy Spirit as one substance (ousia) and three co-equal persons (hypostaseis) was formally ratified.
  • 5.9K
  • 11 Oct 2022
Topic Review
Environmental Protection and Sustainable Development in Madagascar
Located on the East coast of Africa, Madagascar is the world’s fourth-biggest island; Madagascar is host to 12,000 species of vascular plants (96% endemic). Over 90% of all its wildlife is found nowhere else on earth, and 5% of all of the earth’s biodiversity is found in Madagascar. A place where environmental degradation problems have created severe erosion and water quality problems. Despite its biological and cultural diversity, Madagascar is among the poorest countries in the world, with approximately 78% of the population living in extreme poverty with an average income of less than USD 2 per day, and more than three-quarters of the population in rural areas engaged in natural resources dependent livelihood activities. 
  • 5.9K
  • 07 Dec 2022
Topic Review
Satellite-Based Groundwater Monitoring
Satellite is an effective technology to assess water storages remotely through remote sensing and geographic information system (RS and GIS), which are very useful tools in groundwater exploration mapping. They provide inputs to assess the total groundwater resources in a region and for the selection of suitable sites for drilling or artificial recharge.
  • 5.9K
  • 18 Feb 2022
Topic Review
Dyes, Minerals, and Vitamins Used in Cosmetics
Most minerals and vitamins are beneficial when it comes to the improvement of the condition of the skin, hair or nails, and as they are mostly safe for use, they are valued raw materials and cosmetic ingredients. Dyes and pigments, due to the potential negative impact on human health of many of them, are often controversial components of cosmetic preparations. The constantly growing awareness of consumers makes cosmetics manufacturers strive to eliminate potentially harmful substances and use safe raw materials and ingredients of natural origin.
  • 5.9K
  • 23 Nov 2021
Topic Review
Diagnosis and Management of Onychotillomania
Onychotillomania is defined as repetitive picking or pulling of the nail unit, causing damage to the nail matrix, nail bed, nail plate and/or periungual skin.
  • 5.9K
  • 23 Mar 2022
Topic Review
Causes of Egg Spoilage and Preventing Egg Spoilage
Eggs are a rich source of protein, minerals, lipids, and vitamins. Eggs are an essential source of bacterial microflora. Controlling antimicrobial resistance and reducing food loss and waste are essential for a sustainable future. To prevent spoilage and to preserve eggs, a variety of techniques, including thermal and non-thermal, are often used. The decontamination methods for egg preservation that have been applied are discussed. In previous studies, the initial contamination of the eggs varied from 2 to 9 log CFU per egg. Either thermal or non-thermal techniques resulted in reduced concentrations of Salmonella enteritidis, Salmonella typhimurium, and Escherichia coli, respectively, on the surface of the egg that ranged 0.62–5.9 log, 1.27–4.9 log, and 0.06–6.39 log, respectively, for the former, and being 1.2–7.8 log, 5.0–7.8 log, and 6.5–6.6 log, respectively, for the latter. Thermal approaches were more effective than the non-thermal approaches. Some of these methods had negative consequences on the egg’s functionality, while combination methods, such as thermoultrasonifcation (ozone-UV radiation or heat-ozone), mitigated these effects.
  • 5.9K
  • 12 Jan 2023
Topic Review
Positive Psychology
Positive psychology is the scientific study of what makes life most worth living, focusing on both individual and societal well-being. It studies "positive subjective experience, positive individual traits, and positive institutions...it aims to improve quality of life." It is a field of study that has been growing steadily throughout the years as individuals and researchers look for common ground on better well-being. Positive psychology began as a new domain of psychology in 1998 when Martin Seligman chose it as the theme for his term as president of the American Psychological Association. It is a reaction against past practices, which have tended to focus on mental illness and emphasized maladaptive behavior and negative thinking. It builds on the humanistic movement by Abraham Maslow, Rollo May, James Bugental and Carl Rogers, which encourages an emphasis on happiness, well-being, and positivity, thus creating the foundation for what is now known as positive psychology. Positive psychology focuses on eudaimonia, an Ancient Greek term for "the good life" and the concept for reflection on the factors that contribute the most to a well-lived and fulfilling life. Positive psychologists often use the terms subjective well-being and happiness interchangeably. Positive psychologists have suggested a number of factors may contribute to happiness and subjective well-being. For example, social ties with a spouse, family, friends, colleagues, and wider networks; membership in clubs or social organizations; physical exercise, and the practice of meditation. Spirituality can also be considered a factor that leads to increased individual happiness and well-being. Spiritual practice and religious commitment is a topic researchers have been studying as another possible source for increased well-being and an added part of positive psychology. Happiness may rise with increasing financial income, though it may plateau or even fall when no further gains are made or after a certain cut-off amount.
  • 5.9K
  • 24 Nov 2022
Topic Review
Arms Industry
The arms industry, also known as the defense industry or the arms trade, is a global industry responsible for the manufacturing and sales of weapons and military technology. It consists of a commercial industry involved in the research and development, engineering, production, and servicing of military material, equipment, and facilities. Arms-producing companies, also referred to as arms dealers, defence contractors, or as the military industry, produce arms for the armed forces of states and civilians. Departments of government also operate in the arms industry, buying and selling weapons, munitions and other military items. An arsenal is a place where arms and ammunition are made, maintained and repaired, stored, or issued, in any combination, whether privately or publicly owned. Products include guns, artillery, ammunition, missiles, military aircraft, military vehicles, ships, electronic systems, night vision devices, holographic weapon sights, laser rangefinders, laser sights, hand grenades, landmines and more. The arms industry also provides other logistical and operational support. Stockholm International Peace Research Institute (SIPRI) estimated that 2012 military expenditures were roughly $1.8 trillion. This represents a relative decline from 1990 when military expenditures made up 4% of world GDP. Part of the money goes to the procurement of military hardware and services from the military industry. The combined arms sales of the top 100 largest arms-producing companies amounted to an estimated $395 billion in 2012 according to SIPRI. In 2004 over $30 billion were spent in the international arms trade (a figure that excludes domestic sales of arms). According to SIPRI, the volume of international transfers of major weapons in 2010–14 was 16 per cent higher than in 2005–2009. The five biggest exporters in 2010–2014 were the United States, Russia, China, Germany and France, and the five biggest importers were India, Saudi Arabia, China, the United Arab Emirates and Pakistan. Many industrialized countries have a domestic arms-industry to supply their own military forces. Some countries also have a substantial legal or illegal domestic trade in weapons for use by its citizens, primarily for self-defence, hunting or sporting purposes. Illegal trade in small arms occurs in many countries and regions affected by political instability. The Small Arms Survey estimates that 875 million small arms circulate worldwide, produced by more than 1,000 companies from nearly 100 countries. Contracts to supply a given country's military are awarded by governments, making arms contracts of substantial political importance. The link between politics and the arms trade can result in the development of what U.S. President Dwight D. Eisenhower described as a military-industrial complex, where the armed forces, commerce, and politics become closely linked, similarly to the European multilateral defence procurement. Various corporations, some publicly held, others private, bid for these contracts, which are often worth many billions of dollars. Sometimes, as with the contract for the international Joint Strike Fighter, a competitive tendering process takes place, with the decision made on the merits of the designs submitted by the companies involved. Other times, no bidding or competition takes place.
  • 5.9K
  • 10 Dec 2025
Topic Review
Potential Flow Around a Circular Cylinder
In mathematics, potential flow around a circular cylinder is a classical solution for the flow of an inviscid, incompressible fluid around a cylinder that is transverse to the flow. Far from the cylinder, the flow is unidirectional and uniform. The flow has no vorticity and thus the velocity field is irrotational and can be modeled as a potential flow. Unlike a real fluid, this solution indicates a net zero drag on the body, a result known as d'Alembert's paradox.
  • 5.9K
  • 31 Oct 2022
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