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Topic Review
Quantum Dot-Based Lateral Flow Immunoassay
Point-of-care testing (POCT) technology has exhibited an outstanding capability for the detection of several disease biomarkers owing to the fact that such techniques are fast, easy to perform, efficient, and low cost. The lateral flow immunoassay (LFIA) is one such strategy for POCT. LFIA is a well-established platform and a potent assay for fast and inexpensive testing, as this technology is instrumentation independent and allows the visualisation of test results by the naked eye. In order to enhance the sensitivity and specificity of the LFIAs, as well as to allow the quantitation of results, fluorescence immunochromatographic assays have been developed by utilising fluorescent reporters. Fluorescence immunochromatographic assays have advantages over conventional approaches in regard to sensitivity as it produces a higher intensity band on the test and control lines. One such promising fluorescent reporter is quantum dots (QDs). QDs are tiny semiconducting nanocrystals with diameters ranging from 2 to 10 nanometers. QDs have unique electronic characteristics that are intermediate between those of bulk semiconductors and discrete molecules, which is due in part to their high surface-to-volume ratios. The most visible result is fluorescence, in which the nanocrystals emit distinct colours determined by particle size.
  • 3.0K
  • 19 Sep 2022
Topic Review
Working Animal
A working animal is an animal, usually domesticated, that is kept by humans and trained to perform tasks instead of being slaughtered to harvest animal products. Some are beasts of burden (draught animals) that provide transportation (e.g. riding horses and camels) and aid in physical labor (e.g. oxens and elephants), while others are service animals trained to execute certain specialized tasks (e.g. hunting and guide dogs, messenger pigeons and fishing cormorants). They may also be used for milking or herding. Some, at the end of their working lives, may also be used for meat or other products such as leather. The history of working animals may predate agriculture, with dogs used by our hunter-gatherer ancestors. Around the world, millions of animals work in relationship with their owners. Domesticated species are often bred for different uses and conditions, especially horses and working dogs. Working animals are usually raised on farms, though some are still captured from the wild, such as dolphins and some Asian elephants. People have found uses for a wide variety of abilities in animals, and even industrialised societies use many animals for work. People use the strength of horses, elephants, and oxen to pull carts and move loads. Police forces use dogs for finding illegal substances and assisting in apprehending wanted persons, others use dogs to find game or search for missing or trapped people. People use various animals — camels, donkeys, horses, dogs, etc.—for transport, either for riding or to pull wagons and sleds. Other animals, including dogs and monkeys, help disabled people. On rare occasions, wild animals are not only tamed, but trained to perform work—though often solely for novelty or entertainment, as such animals tend to lack the trustworthiness and mild temper of true domesticated working animals. Conversely, not all domesticated animals are working animals. For example, while cats may catch mice, it is an instinctive behaviour, not one that can be trained by human intervention. Other domesticated animals, such as sheep or rabbits, may have agricultural uses for meat, hides and wool, but are not suitable for work. Finally, small domestic pets, such as most small birds (other than certain types of pigeon) are generally incapable of performing work other than providing companionship.
  • 3.0K
  • 14 Nov 2022
Topic Review
Visegrád Group
The Visegrád Group, Visegrád Four, or V4, is a cultural and political alliance of four Central European countries – the Czech Republic, Hungary, Poland and Slovakia, that are members of the European Union (EU) and NATO – for the purposes of advancing military, cultural, economic and energy cooperation with one another along with furthering their integration in the EU. The Group traces its origins to the summit meetings of leaders from Czechoslovakia, Hungary, and Poland held in the Hungarian castle-town of Visegrád on 15 February 1991. Visegrád was chosen as the location for the 1991 meeting as an intentional allusion to the medieval Congress of Visegrád in 1335 between John I of Bohemia, Charles I of Hungary and Casimir III of Poland. After the dissolution of Czechoslovakia in 1993, the Czech Republic and Slovakia became independent members of the group, thus increasing the number of members from three to four. All four members of the Visegrád Group joined the European Union on 1 May 2004.
  • 3.0K
  • 15 Nov 2022
Topic Review
Neonatal Early-Onset Sepsis
Neonatal early-onset sepsis (EOS) is defined as an invasive infection that occurs in the first 72 h of life. The incidence of EOS varies from 0.5–2 per 1000 live births in developed countries, up to 9.8 per 1000 live births in low resource settings, generating a high mortality rate, especially in extremely low birth weight neonates. Clinical signs are nonspecific, leading to a late diagnosis and high mortality. Currently, there are several markers used for sepsis evaluation, such as hematological indices, acute phase reactants, cytokines, which by themselves do not show acceptable sensitivity and specificity for the diagnosis of EOS in neonates. Newer and more selective markers have surfaced recently, such as presepsin and endocan, but they are currently only in the experimental research stages.
  • 3.0K
  • 28 Sep 2021
Topic Review
Factors Affecting Electrospinning
Electrospinning can produce continuous nanofibers from a variety of materials. Processional, physical, systemic, and solution parameters, among others, impact the fiber morphology and properties of electrospun fibers.
  • 3.0K
  • 13 Apr 2023
Topic Review
Ocular Medication Routes of Administration
Ocular drug administration encompasses a range of routes, each with its own advantages and limitations. The available methods include systemic delivery (such as oral, intravenous, and subcutaneous routes) as well as local delivery options (including topical eye drops, periocular or intravitreal injections, and intravitreal implants). While these approaches can be effective in delivering medications to the eye, they also have inherent drawbacks, which will be explored in greater detail in this entry. Notably, understanding the strengths and limitations of these ocular drug administration routes is crucial for optimizing therapy and achieving the desired therapeutic outcomes while minimizing potential adverse effects.   
  • 3.0K
  • 04 Dec 2023
Topic Review
Neo-Advaita
Neo-Advaita, also called the Satsang-movement and Nondualism, is a New Religious Movement, emphasizing the direct recognition of the non-existence of the "I" or "ego," without the need of preparatory practice. Its teachings are derived from, but not authorised by, the teachings of the 20th century sage Ramana Maharshi, as interpreted and popularized by H. W. L. Poonja and several of his western students. It is part of a larger religious current called immediatism by Arthur Versluis, which has its roots in both western and eastern spirituality. Western influences are western esoteric traditions like Transcendentalism, and "New Age millennialism, self-empowerment and self-therapy". Neo-Advaita makes little use of the "traditional language or cultural frames of Advaita Vedanta", and some have criticised it for its lack of preparatory training, and regard enlightenment-experiences induced by Neo-Advaita as superficial.
  • 3.0K
  • 16 Nov 2022
Topic Review
Food-Grade Nanoemulsions
Nanoemulsions, exhibiting droplet sizes of <200 nm, represent liquid-in-liquid dispersions that are kinetically stable. Water and oil are the two incompatible liquids most extensively applied in commercial environments. Because of their small size, characteristics such as visible transparency, high surface area per unit volume, sound stability and tunable rheology are often observed. Additionally, large-scale nanoemulsions’ preparation is easily achievable in industrial conditions. Therefore, nanoemulsions are especially suitable for commercial applications.
  • 3.0K
  • 22 Dec 2021
Topic Review
Pegasus
Pegasus, the winged horse of Greek mythology, is a prominent constellation in the northern sky, known for its distinctive "Great Square" asterism. As one of the 48 constellations cataloged by the ancient Greek astronomer Ptolemy, Pegasus has a rich cultural and astronomical significance. Its association with the mythical creature Pegasus, ridden by heroes such as Perseus and Bellerophon, adds to its allure and makes it a captivating subject for stargazers.
  • 3.0K
  • 15 Mar 2024
Topic Review
Salvage Surgery
The representative surgical intervention for unresectable stage III/IV NSCLC is salvage surgery, which refers to surgical treatment for local residual/recurrent lesions after definitive non-surgical treatment. Surgical intervention is also used for an oligometastatic stage IV NSCLC. 
  • 3.0K
  • 29 Apr 2021
Topic Review
Regulationary Factors of the Peroxisomal β-Oxidation
Beta-oxidation(β-oxidation) is an important metabolic process involving multiple steps by which fatty acid molecules are broken down to produce energy. The very long-chain fatty acids (VLCFAs), a type of fatty acid (FA), are usually highly toxic when free in vivo, and their oxidative metabolism depends on the peroxisomal β-oxidation. Although peroxisomal β-Oxidation attracts less research than mitochondria, the importance of the peroxisomal β-oxidation molecular mechanism can still be spotted from some mechanisms involved in upstream regulation.
  • 3.0K
  • 07 Jul 2022
Topic Review
Nitrogen, Phosphorus and Microalgal
Microalgae can be used as a source of alternative food, animal feed, biofuel, fertilizer, cosmetics, nutraceuticals and for pharmaceutical purposes. The extraction of organic constituents from microalgae cultivated in the different nutrient compositions is influenced by microalgal growth rates, biomass yield and nutritional content in terms of lipid and fatty acid production. In this context, nutrient composition plays an important role in microalgae cultivation, and depletion and excessive sources of this nutrient might affect the quality of biomass. Investigation on the role of nitrogen and phosphorus, which are crucial for the growth of algae, has been addressed. However, there are challenges for enhancing nutrient utilization efficiently for large scale microalgae cultivation. Hence, this study aims to highlight the level of nitrogen and phosphorus required for microalgae cultivation and focuses on the benefits of nitrogen and phosphorus for increasing biomass productivity of microalgae for improved lipid and fatty acid quantities. Furthermore, the suitable extraction methods that can be used to utilize lipid and fatty acids from microalgae for biofuel have also been reviewed.
  • 3.0K
  • 03 Mar 2021
Topic Review
Hop
Hops is considered a short-day, temperate species, so the major challenge for the development of hop cultivation in Brazil, with high-yield capacity and with local typicity of bitterness and aroma, is the adaptation of cultivars to the photoperiod conditions in subtropical regions. 
  • 3.0K
  • 20 May 2022
Topic Review
Online Hate Speech
Online hate speech is a type of speech that takes place online with the purpose of attacking a person or a group based on their race, religion, ethnic origin, sexual orientation, disability, or gender. Online hate speech is the expression of conflicts between different groups within and across societies. Online hate speech is a vivid example of how the Internet brings both opportunities and challenges regarding the freedom of expression and speech while also defending human dignity. Multilateral treaties such as the International Covenant on Civil and Political Rights (ICCPR) have sought to define its contours. Multi-stakeholders processes (e.g. the Rabat Plan of Action) have tried to bring greater clarity and suggested mechanisms to identify hateful messages. Yet, hate speech is still a generic term in everyday discourse, mixing concrete threats to individuals and/or groups with cases in which people may be simply venting their anger against authority. Internet intermediaries—organizations that mediate online communication such as Facebook, Twitter, and Google—have advanced their own definitions of hate speech that bind users to a set of rules and allow companies to limit certain forms of expression. National and regional bodies have sought to promote understandings of the term that are more rooted in local traditions. The Internet's speed and reach makes it difficult for governments to enforce national legislation in the virtual world. Social media is a private space for public expression, which makes it difficult for regulators. Some of the companies owning these spaces have become more responsive towards tackling the problem of hate speech online. Politicians, activists, and academics discuss the character of online hate speech and its relation to offline speech and action, but the debates tend to be removed from systematic empirical evidence. The character of perceived hate speech and its possible consequences has led to placing much emphasis on the solutions to the problem and on how they should be grounded in international human rights norms. Yet this very focus has also limited deeper attempts to understand the causes underlying the phenomenon and the dynamics through which certain types of content emerge, diffuse and lead—or not—to actual discrimination, hostility or violence. Online hate speech has been on the rise since the start of 2020, with COVID-19 tensions, Anti-Asian rhetoric, ongoing racial injustice, mass civil unrest, violence, and the 2020 Presidential Election. Yet, many instances of hate speech have been refuted with the First Amendment, which allows online hate speech to continue.
  • 3.0K
  • 31 Oct 2022
Topic Review
Additively Manufactured Aluminium Alloys
Metal additive manufacturing (MAM), also known as metal 3D printing, is a rapidly growing industry based on the fabrication of complex metal parts with improved functionalities. During MAM, metal parts are produced in a layer by layer fashion using 3D computer–aided design models. The advantages of using this technology includes the reduction of materials waste, high efficiency for small production runs, near net shape manufacturing, ease of change or revision of versions of a product, support of lattice structures, and rapid prototyping. Numerous metals and alloys can nowadays be processed by additive manufacturing techniques. Among them, Al-based alloys are of great interest for the automotive and aeronautic industry due to their relatively high strength and stiffness to weight ratio, good wear and corrosion resistance, and recycling potential. The special conditions associated with the MAM processes are known to produce in these materials a very fine microstructure with unique directional growth features far from equilibrium. This distinctive microstructure, together with other special features and microstructural defects originating from the additive manufacturing process are known to greatly influence the corrosion behavior of these materials. Several works have already been conducted in this direction. However, a number of issues concerning the corrosion and corrosion protection of these materials are still not well understood. This work reviews the main studies to date investigating the corrosion aspects of additively manufactured aluminium alloys. It also provides a summary and outlook of relevant directions to be explored in future research.
  • 3.0K
  • 13 Jan 2021
Topic Review
Learning Disability
Learning disability, learning disorder, or learning difficulty (British English) is a condition in the brain that causes difficulties comprehending or processing information and can be caused by several different factors. Given the "difficulty learning in a typical manner", this does not exclude the ability to learn in a different manner. Therefore, some people can be more accurately described as having a "learning difference", thus avoiding any misconception of being disabled with a lack of ability to learn and possible negative stereotyping. In the United Kingdom, the term "learning disability" generally refers to an intellectual disability, while difficulties such as dyslexia and dyspraxia are usually referred to as "learning difficulties". While learning disability and learning disorder are often used interchangeably, they differ in many ways. Disorder refers to significant learning problems in an academic area. These problems, however, are not enough to warrant an official diagnosis. Learning disability, on the other hand, is an official clinical diagnosis, whereby the individual meets certain criteria, as determined by a professional (such as a psychologist, psychiatrist, speech language pathologist, or pediatrician). The difference is in degree, frequency, and intensity of reported symptoms and problems, and thus the two should not be confused. When the term "learning disorder" is used, it describes a group of disorders characterized by inadequate development of specific academic, language, and speech skills. Types of learning disorders include reading (dyslexia), arithmetic (dyscalculia) and writing (dysgraphia). The unknown factor is the disorder that affects the brain's ability to receive and process information. This disorder can make it problematic for a person to learn as quickly or in the same way as someone who is not affected by a learning disability. People with a learning disability have trouble performing specific types of skills or completing tasks if left to figure things out by themselves or if taught in conventional ways. Individuals with learning disabilities can face unique challenges that are often pervasive throughout the lifespan. Depending on the type and severity of the disability, interventions, and current technologies may be used to help the individual learn strategies that will foster future success. Some interventions can be quite simplistic, while others are intricate and complex. Current technologies may require student training to be effective classroom supports. Teachers, parents, and schools can create plans together that tailor intervention and accommodations to aid the individuals in successfully becoming independent learners. A multi-disciplinary team frequently helps to design the intervention and to coordinate the execution of the intervention with teachers and parents. This team frequently includes school psychologists, special educators, speech therapists (pathologists), occupational therapists, psychologists, ESL teachers, literacy coaches, and/or reading specialists.
  • 3.0K
  • 10 Nov 2022
Biography
Juan Martín Maldacena
Juan Martín Maldacena (September 10, 1968 ) is an Argentine theoretical physicist and the Carl P. Feinberg Professor in the School of Natural Sciences at the Institute for Advanced Study.[1] He has made significant contributions to the foundations of string theory and quantum gravity. His most famous discovery is the AdS/CFT correspondence, a realization of the holographic principle in string t
  • 3.0K
  • 24 Nov 2022
Topic Review
Metal Matrix Composite
Composites are generally categorized into three main categories based on the matrix substance. They are called metal matrix composite (MMC), polymer matrix composite (PMC), and ceramic matrix composite (CMC), respectively. MMC gives more elevated ductile properties than CMCs and better environmental stability than PMCs. Additionally, MMCs offer good thermal conductivity (from 220 to 580 W·m−1·K−1), wear resistance (0.01025), wear rate (g·m−1), erosion, and shear strength.
  • 3.0K
  • 06 Sep 2021
Topic Review
The 4 Helix Model and Tourism Social Entrepreneurships
The COVID-19 crisis has promoted innovation, support, and incentives among the four helixes, in which the STEs have benefited. As conclusions, the four helix model is functional to face the adversities of COVID-19 as long as there is planning within the entrepreneurships and the link with said model helix participants.
  • 3.0K
  • 10 Jan 2022
Topic Review
Effects of Berberine against Pancreatic Cancer
The pancreas is a glandular organ with endocrine and exocrine functions necessary for the maintenance of blood glucose homeostasis and secretion of digestive enzymes. Pancreatitis is characterized by inflammation of the pancreas leading to temporary or permanent pancreatic dysfunction. Inflammation and fibrosis caused by chronic pancreatitis exacerbate malignant transformation and significantly increase the risk of developing pancreatic cancer, the world’s most aggressive cancer with a 5-year survival rate less than 10%. Berberine (BBR) is a naturally occurring plant-derived polyphenol present in a variety of herbal remedies used in traditional medicine to treat ulcers, infections, jaundice, and inflammation.
  • 3.0K
  • 20 Dec 2022
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