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Topic Review
Histopathology of Choroidal Melanoma
Choroidal melanoma (CM), despite its rarity, is the most frequent intraocular malignancy. Over time, several histological variants of CM have been distinguished, including spindle A and B cell, fascicular, epithelioid and necrotic type. However, they have been progressively abandoned as having no prognostic value and currently, the American Joint Committee of Cancer (AJCC) classification identifies three CM cell types: spindle, epithelioid and mixed cell type. Other rare histological variants of CM include: (i) diffuse melanoma; (ii) clear cell; and (iii) balloon cell melanoma. Immunohistochemically, CMs are stained with Human Melanoma Black 45 (HMB45) antigen, S-100 protein, Melan-A (also known as melanoma antigen recognized by T cells 1/MART-1), melanocyte inducing transcription factor (MITF), tyrosinase, vimentin, and Sex determining region Y-Box 10 (SOX10). Several genetic and histopathological prognostic factors of CM have been reported in the literature, including epithelioid cell type, TNM staging, extraocular extension, monosomy 3 and 6p gain and loss of BAP-1 gene. The aim of this review was to summarize the histopathological, immunohistochemical and genetic features of CM, establishing “the state of the art” and providing colleagues with practical tools to promptly deal with patients affected by this rare malignant neoplasm.
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  • 17 Dec 2020
Topic Review
Broadband Power Line
Broadband Power Line (BPL) communications are enlisted to play an important role in the development of new Smart Grid (SG) services and applications, due to the high-performance features that will be demanded in the transformation of the electrical grid model in the next few years. BPL communications are the most immediate and affordable answer to the SG challenge in the distribution grid. While Smart Metering has been instrumental to reaching the outer edge of the grid (i.e., the customer), the capability to deploy broadband communications through the grid is not just a question of the natural evolution of telecommunication technologies but is a requirement for accomplishing the SG evolution. In particular, BPL technologies are a key tool for the control and monitoring of secondary substations. They will also be essential in the distribution grid, in terms of PQ monitoring and distribution generation, especially considering the growth of solar and wind power sources and the progressive introduction of massive EV fleets, with hundreds of vehicles charging and discharging at the same time. In addition, BPL technologies have a great potential towards the diagnosis of the power grid and security assurance. The methods for cable health monitoring are mainly based on the topological parameters of the network, physical properties of the cable, and the measured Quality of Service (QoS) parameters, while other methods include simulations and diagnostics solutions.
  • 3.2K
  • 24 Jun 2022
Topic Review
Attention-Setting and Human Mental Function: An Introduction
Adapted from the longer article  [url link to original article] This entry provides an introduction to experimental research on top-down human attention in complex scenes, written for cognitive scientists in general. The entry emphasizes effects of human goals and intention on mental function, measured with behavioral experiments. Top-down attention is described as attention-setting — an open category of skillful mental actions that initiate particular task sets, which are assembled from a wide range of mental processes. Experimental research on visual search, task switching, and temporal attention is outlined and extended to the important human time scale of seconds.
  • 3.2K
  • 21 Jun 2022
Topic Review
Cactus
A cactus (plural cacti, cactuses, or less commonly, cactus) is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1750 known species of the order Caryophyllales. The word cactus derives, through Latin, from the Ancient Greek word κάκτος (káktos), a name originally used by Theophrastus for a spiny plant whose identity is now not certain. Cacti occur in a wide range of shapes and sizes. Although some species live in quite humid environments, most cacti live in habitats subject to at least some drought. Many live in extremely dry environments, even being found in the Atacama Desert, one of the driest places on Earth. Because of this, cacti show many adaptations to conserve water. For example, almost all cacti are succulents, meaning they have thickened, fleshy parts adapted to store water. Unlike many other succulents, the stem is the only part of most cacti where this vital process takes place. Most species of cacti have lost true leaves, retaining only spines, which are highly modified leaves. As well as defending against herbivores, spines help prevent water loss by reducing air flow close to the cactus and providing some shade. In the absence of true leaves, cacti's enlarged stems carry out photosynthesis. Cacti are native to the Americas, ranging from Patagonia in the south to parts of western Canada in the north—except for Rhipsalis baccifera, which also grows in Africa and Sri Lanka. Cactus spines are produced from specialized structures called areoles, a kind of highly reduced branch. Areoles are an identifying feature of cacti. As well as spines, areoles give rise to flowers, which are usually tubular and multipetaled. Many cacti have short growing seasons and long dormancies and are able to react quickly to any rainfall, helped by an extensive but relatively shallow root system that quickly absorbs any water reaching the ground surface. Cactus stems are often ribbed or fluted, which allows them to expand and contract easily for quick water absorption after rain, followed by retention over long drought periods. Like other succulent plants, most cacti employ a special mechanism called "crassulacean acid metabolism" (CAM) as part of photosynthesis. Transpiration, during which carbon dioxide enters the plant and water escapes, does not take place during the day at the same time as photosynthesis, but instead occurs at night. The plant stores the carbon dioxide it takes in as malic acid, retaining it until daylight returns, and only then using it in photosynthesis. Because transpiration takes place during the cooler, more humid night hours, water loss is significantly reduced. Many smaller cacti have globe-shaped stems, combining the highest possible volume for water storage with the lowest possible surface area for water loss from transpiration. The tallest free-standing cactus is Pachycereus pringlei, with a maximum recorded height of 19.2 m (63 ft), and the smallest is Blossfeldia liliputiana, only about 1 cm (0.4 in) in diameter at maturity. A fully grown saguaro (Carnegiea gigantea) is said to be able to absorb as much as 200 U.S. gallons (760 l; 170 imp gal) of water during a rainstorm. A few species differ significantly in appearance from most of the family. At least superficially, plants of the genera Leuenbergeria, Rhodocactus and Pereskia resemble other trees and shrubs growing around them. They have persistent leaves, and when older, bark-covered stems. Their areoles identify them as cacti, and in spite of their appearance, they, too, have many adaptations for water conservation. Leuenbergeria is considered close to the ancestral species from which all cacti evolved. In tropical regions, other cacti grow as forest climbers and epiphytes (plants that grow on trees). Their stems are typically flattened, almost leaf-like in appearance, with fewer or even no spines, such as the well-known Christmas cactus or Thanksgiving cactus (in the genus Schlumbergera). Cacti have a variety of uses: many species are used as ornamental plants, others are grown for fodder or forage, and others for food (particularly their fruit). Cochineal is the product of an insect that lives on some cacti. Many succulent plants in both the Old and New World – such as some Euphorbiaceae (euphorbias) – are also spiny stem succulents and because of this are sometimes incorrectly referred to as "cactus".
  • 3.2K
  • 14 Nov 2022
Topic Review
Samsung Knox
Samsung Knox is a proprietary security and management framework pre-installed on most Samsung mobile devices. Its primary purpose is to provide organizations with a toolset for managing work devices, such as employee mobile phones or interactive kiosks. Knox provides more granular control over the standard work profile to manage capabilities found only on Samsung devices. Knox's features fall within three categories: data security, device manageability, and VPN capability. Knox also provides web-based services for organizations to manage their devices. Organizations can customize their managed mobile devices by configuring various functions, including pre-loaded applications, settings, boot-up animations, home screens, and lock screens. As of December 2020, organizations can use specific Samsung mobile device cameras as barcode scanners, using Knox services to capture and analyze the data.
  • 3.2K
  • 17 Nov 2022
Topic Review
Twinning-Induced Plasticity
Twinning-induced plasticity (TWIP) steel is a second-generation advanced high strength steel grade developed for automotive applications. TWIP steels exhibit an excellent combination of strength and ductility, mainly originating from the activation of deformation twinning.
  • 3.2K
  • 23 Feb 2021
Topic Review Peer Reviewed
Otovestibular Symptoms of COVID-19 and Its Vaccines/Treatments
The rapidly developing literature regarding COVID-19 and its treatments has documented an impressive breadth of pathology across multiple organ systems. In this entry, researchers highlight the audiologic and vestibular manifestations that have been reported in association with COVID-19, its vaccines, and some of its treatments.
  • 3.2K
  • 08 Jul 2022
Topic Review
Orange Peel Boards
The Orange Peel Board is a panel made by mixture of different proportions dried peels and wet peels. The commonly used processing method is thermo-pressing.  
  • 3.2K
  • 19 Jul 2021
Topic Review
Advanced Glycation End Products and Cardiovascular Disease
Epidemiological studies demonstrate the role of early and intensive glycemic control in the prevention of micro and macrovascular disease in both type 1 and type 2 diabetes mellitus (DM). Hyperglycemia elicits several pathways related to the etiopathogenesis of cardiovascular disease (CVD), including the generation of advanced glycation end products (AGEs). 
  • 3.2K
  • 11 Mar 2022
Topic Review
The Occurrence of Microorganisms in Grassland Soils
Soil microorganisms are responsible for the mineralization of organic compounds and the course of various biogeochemical cycles. They have an influence on the biodiversity of entire ecosystems, including the plant cover. They are responsible for the productivity of soil and its structure, and they also affect the circulation of elements in nature. The count and species composition of soil microorganisms depend mainly on the physicochemical properties of the pedon, the amount of nutrients, the type of soil, and the species composition of the plant community. Plants significantly influence the species composition of soil microbial communities through the release or loss of compounds from plant roots to the surrounding soil environment and decomposition of litter and roots.
  • 3.2K
  • 19 May 2022
Topic Review
Infrared Thermography for Condition-Based Monitoring in Electrical Energy
Condition-based monitoring (CBM) has emerged as a critical instrument for lowering the cost of unplanned operations while also improving the efficacy, execution, and dependability of tools. Thermal abnormalities can be thoroughly examined using thermography for condition monitoring.
  • 3.2K
  • 02 Sep 2022
Topic Review
Non-Native Guinea Grass
Guinea grass (Panicum maximum Jacq., renamed Megathyrsus maximus Jacq.) is a native forage plant in Africa of great economic value, but it was introduced in almost all tropical countries as a source of animal forage.
  • 3.2K
  • 30 Jun 2021
Topic Review
Classic Car
A classic car is an older automobile; the exact definition varies around the world. The common theme is of an older car with enough historical interest to be collectable and worth preserving or restoring rather than scrapping. Cars 20 years and older typically fall into the classic class. Organizations such as the Classic Car Club of America (CCCA) and the Antique Automobile Club of America (AACA) maintain a list of eligible unmodified cars that are called "classic". These are described as "fine" or "distinctive" automobile, either American or foreign built, produced between 1915 to 1998. Post–World War II "classic cars" are not precisely defined and the term is often applied to any older vehicle.
  • 3.2K
  • 02 Nov 2022
Topic Review
Data Ownership in Healthcare
This section briefly discusses this issue of data ownership in the light of recent privacy laws. These laws have a very large impact on the topic of data sharing. It shows that these privacy laws provide rights to the patient, but they do not necessarily make clear who is the owner of the data. They only provide a legal framework for the handling of the data.
  • 3.2K
  • 05 Feb 2021
Topic Review
Host Defenses to Viruses
The constant battle between viruses and their hosts leads to their reciprocal evolution. Viruses regularly develop survival strategies against host immunity, while their ability to replicate and disseminate is countered by the antiviral defense mechanisms that host mount. Although most viral infections are generally controlled by the host’s immune system, some viruses do cause overt damage to the host. The outcome can vary widely depending on the properties of the infecting virus and the circumstances of infection but also depends on several factors controlled by the host, including host genetic susceptibility to viral infections.
  • 3.2K
  • 16 Feb 2022
Topic Review
Dialysis
In medicine, dialysis (from Greek διάλυσις, dialysis, "dissolution"; from διά, dia, "through", and λύσις, lysis, "loosening or splitting") is the process of removing excess water, solutes, and toxins from the blood in people whose kidneys can no longer perform these functions naturally. This is referred to as renal replacement therapy. The first successful dialysis was performed in 1943. Dialysis may need to be initiated when there is a sudden rapid loss of kidney function, known as acute kidney injury (previously called acute renal failure), or when a gradual decline in kidney function, chronic kidney disease, reaches stage 5. Stage 5 chronic renal failure is reached when the glomerular filtration rate is 10–15% of normal, creatinine clearance is less than 10 mL per minute and uremia is present. Dialysis is used as a temporary measure in either acute kidney injury or in those awaiting kidney transplant and as a permanent measure in those for whom a transplant is not indicated or not possible. In Australia, Canada, the United Kingdom, and the United States, dialysis is paid for by the government for those who are eligible. In research laboratories, dialysis technique can also be used to separate molecules based on their size. Additionally, it can be used to balance buffer between a sample and the solution "dialysis bath" or "dialysate" that the sample is in. For dialysis in a laboratory, a tubular semipermeable membrane made of cellulose acetate or nitrocellulose is used. Pore size is varied according to the size separation required with larger pore sizes allowing larger molecules to pass through the membrane. Solvents, ions and buffer can diffuse easily across the semipermeable membrane, but larger molecules are unable to pass through the pores. This can be used to purify proteins of interest from a complex mixture by removing smaller proteins and molecules.
  • 3.2K
  • 07 Nov 2022
Topic Review
Trace Minerals in Animal Nutrition
Trace mineral refers to the nutritional elements added to production and companion animal diets in micro quantities. They are involved in structural, physiological, catalytic, and regulatory functions in animals. The importance of dietary supplementation of animal feeds with trace minerals is irrefutable, with various forms of both organic and inorganic products commercially available.
  • 3.2K
  • 22 Sep 2022
Topic Review
Timoshenko Beam Theory
The Timoshenko beam theory was developed by Stephen Timoshenko early in the 20th century. The model takes into account shear deformation and rotational bending effects, making it suitable for describing the behaviour of thick beams, sandwich composite beams, or beams subject to high-frequency excitation when the wavelength approaches the thickness of the beam. The resulting equation is of 4th order but, unlike Euler–Bernoulli beam theory, there is also a second-order partial derivative present. Physically, taking into account the added mechanisms of deformation effectively lowers the stiffness of the beam, while the result is a larger deflection under a static load and lower predicted eigenfrequencies for a given set of boundary conditions. The latter effect is more noticeable for higher frequencies as the wavelength becomes shorter (in principle comparable to the height of the beam or shorter), and thus the distance between opposing shear forces decreases. If the shear modulus of the beam material approaches infinity—and thus the beam becomes rigid in shear—and if rotational inertia effects are neglected, Timoshenko beam theory converges towards ordinary beam theory.
  • 3.2K
  • 15 Nov 2022
Topic Review
Horizontal transfer of Resistance Genes
Emergence and rapid spread of antibiotic resistance has posed a serious threat to public health and undermined decades of progress made in the fight against bacterial infections. Plasmid-mediated horizontal tranfer of antibiotic resistance genes (ARGs) has been recognized as the most dominant dissemination pathway of ARGs in humans, animals and environmental settings. In particular, four pathways including conjugation, transformation, transduction and vesiduction account for horizontal transfer of antibiotic resistance genes. A better understanding of these pathways and underlying mechanisms would contribute to developing more effective stategies to control the prevalence of ARGs.
  • 3.2K
  • 14 Aug 2020
Topic Review
ESG in the Banking Sector
Environmental, Social and Governance (ESG) is currently one of the main focus areas for policy makers worldwide.
  • 3.2K
  • 06 Dec 2021
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