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Topic Review
Improvised Artillery in the Syrian Civil War
Improvised artillery in the Syrian Civil War are improvised firearms created and used by factions of the Syrian Civil War, most notably Syrian opposition forces. The weapons include the Hell Cannon and its variants, the Thunder Cannon and the Mortar Cannon. The weapons have been criticized for being inaccurate.
  • 5.6K
  • 21 Oct 2022
Topic Review
Pedogenesis
Pedogenesis (from the Greek pedo-, or pedon, meaning 'soil, earth,' and genesis, meaning 'origin, birth') (also termed soil development, soil evolution, soil formation, and soil genesis) is the process of soil formation as regulated by the effects of place, environment, and history. Biogeochemical processes act to both create and destroy order (anisotropy) within soils. These alterations lead to the development of layers, termed soil horizons, distinguished by differences in color, structure, texture, and chemistry. These features occur in patterns of soil type distribution, forming in response to differences in soil forming factors. Pedogenesis is studied as a branch of pedology, the study of soil in its natural environment. Other branches of pedology are the study of soil morphology, and soil classification. The study of pedogenesis is important to understanding soil distribution patterns in current (soil geography) and past (paleopedology) geologic periods.
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  • 03 Nov 2022
Topic Review
Cemetery Tourism
Cemetery tourism (thanatourism) is a specific sub-section of dark tourism that is becoming increasingly popular. Tourists wander through burial grounds with the aim of discovering the artistic, architectural, historical, and scenic heritage that often abounds in cemeteries. The changing perception of cemeteries from a place for burial towards a cultural heritage space provides several opportunities for tourism. It enables the community to explore the development of products and services that help the destination to gain new income while preserving its heritage.
  • 5.6K
  • 10 Mar 2022
Topic Review
Calcium Propionate in Dairy Cows
Calcium propionate is a safe and reliable food and feed additive. It can be metabolized and absorbed by humans and animals as a precursor for glucose synthesis. In addition, calcium propionate provides essential calcium to mammals. In the perinatal period of dairy cows, many cows cannot adjust to the tremendous metabolic, endocrine, and physiological changes, resulting in ketosis and fatty liver due to a negative energy balance (NEB) or milk fever induced by hypocalcemia. On hot weather days, cow feed (TMR or silage) is susceptible to mildew, which produces mycotoxins. These two issues are closely related to dairy health and performance. Propionic acid is the primary gluconeogenic precursor in dairy cows and one of the safest mold inhibitors. Therefore, calcium propionate, which can be hydrolyzed into propionic acid and Ca2+ in the rumen, may be a good feed additive for alleviating NEB and milk fever in the perinatal period of dairy cows. It can also be used to inhibit TMR or silage deterioration in hot weather and regulate rumen development in calves. This paper reviews the application of calcium propionate in dairy cows.
  • 5.6K
  • 27 Oct 2020
Topic Review
P5 (Microarchitecture)
The original Pentium microprocessor was introduced by Intel on March 22, 1993. It was instruction set compatible with the 80486 but was a new and very different microarchitecture design. The P5 Pentium was the first superscalar x86 microarchitecture and the world’s first superscalar microprocessor to be in mass production. It included dual integer pipelines, a faster floating-point unit, wider data bus, separate code and data caches as well as many other techniques and features to enhance performance and support security, encryption, and multiprocessing for workstations and servers. Considered the fifth main generation in the 8086 compatible line of processors, its implementation and microarchitecture was called P5. As with all new processors from Intel since the Pentium, some new instructions were added to enhance performance for specific types of workloads. The Pentium was the first Intel x86 to build in robust hardware support for multiprocessing similar to that of large IBM mainframe computers. Intel worked closely with IBM to define this capability and then Intel designed it into the P5 microarchitecture. This new capability was not present in prior x86 generations or x86 copies from competitors. In order to realize its greatest potential, compilers had to be optimized to take advantage of the instruction level parallelism provided by the new superscalar dual pipelines and applications needed to be recompiled. Intel spent substantial effort and resources working with development tool vendors, and major ISV and OS companies to optimize their products for Pentium prior to product launch. In October 1996, the similar Pentium MMX was introduced, complementing the same basic microarchitecture with the MMX instruction set, larger caches, and some other enhancements. Competitors included Motorola 68040, Motorola 68060, PowerPC 601, SPARC, MIPS, Alpha families, most of which also used a superscalar in-order dual instruction pipeline configuration at some time. Intel discontinued the P5 Pentium processors (sold as a cheaper product since the Pentium II of 1997) in early 2000 in favor of the Celeron processor, which had also replaced the 80486 brand.
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  • 06 Oct 2022
Topic Review
Passivation
Passivation, in physical chemistry and engineering, refers to coating a material so it becomes "passive", that is, less readily affected or corroded by the environment. Passivation involves creation of an outer layer of shield material that is applied as a microcoating, created by chemical reaction with the base material, or allowed to build by spontaneous oxidation in the air. As a technique, passivation is the use of a light coat of a protective material, such as metal oxide, to create a shield against corrosion. Passivation of silicon is used during fabrication of microelectronic devices. In electrochemical treatment of water, passivation reduces the effectiveness of the treatment by increasing the circuit resistance, and active measures are typically used to overcome this effect, the most common being polarity reversal, which results in limited rejection of the fouling layer.[clarification needed] When exposed to air, many metals naturally form a hard, relatively inert surface layer, usually an oxide (termed the "native oxide layer") or a nitride, that serves as a passivation layer. In the case of silver, the dark tarnish is a passivation layer of silver sulfide formed from reaction with environmental hydrogen sulfide. (In contrast, metals such as iron oxidize readily to form a rough porous coating of rust that adheres loosely and sloughs off readily, allowing further oxidation.) The passivation layer of oxide markedly slows further oxidation and corrosion in room-temperature air for aluminium, beryllium, chromium, zinc, titanium, and silicon (a metalloid). The inert surface layer formed by reaction with air has a thickness of about 1.5 nm for silicon, 1–10 nm for beryllium, and 1 nm initially for titanium, growing to 25 nm after several years. Similarly, for aluminium, it grows to about 5 nm after several years. Surface passivation refers to a common semiconductor device fabrication process critical to modern electronics. It is the process by which a semiconductor surface such as silicon is rendered inert, and does not change semiconductor properties when it interacts with air or other materials. This is typically achieved by thermal oxidation, in which the material is heated and exposed to oxygen. In a silicon semiconductor, this process allows electricity to reliably penetrate to the conducting silicon below the surface, and to overcome the surface states that prevent electricity from reaching the semiconducting layer. Surface passivation by thermal oxidation is one of the key features of silicon technology, and is dominant in microelectronics. The surface passivation process was developed by Mohamed M. Atalla at Bell Labs in the late 1950s. It is commonly used to manufacture MOSFETs (metal-oxide-semiconductor field-effect transistors) and silicon integrated circuit chips (with the planar process), and is critical to the semiconductor industry. Surface passivation is also critical to solar cell and carbon quantum dot technologies.
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  • 03 Nov 2022
Topic Review
Development of Single-cell RNA Sequencing
Single-cell RNA sequencing (scRNA-seq) technology provides a powerful tool for understanding complex biosystems at the single-cell and single-molecule level. The application of droplet- and microwell-based microfluidics in scRNA-seq has contributed greatly to improving sequencing throughput. 
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  • 01 Jul 2022
Topic Review
Airport Business Model
The growth in demand for air transport caused airports to invest in the development of infrastructure and service quality. Therefore, airports, which are mostly owned and operated by governments, shifted to public enterprise management and multi-business companies to become more competitive and profitable. Massive funding was required to refurbish airports and improve their cost efficiency. The airports were tasked with finding managerial instruments to provide a new business model. 
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  • 22 Jul 2022
Topic Review
Greenery Systems
Urbanization, when it is not planned carefully, are highly effecting the urban heat island. To mitigate the problem, urbanization planning must take into consideration the implementation of greenery systems and sustainable ecosystems for buildings as part of the solution in addition to the outer space. The mitigation techniques that are influencing the urban heat index may be the greenery systems applied on buildings, or urban green spaces that include large land and large scale systems, such as lakes and parks. The objective of the current article is to compile, discusses and compare the previous studies on greenery systems, like green roofs and green walls, how they are supporting the energy saving and improve thermal conditions in the building sector, as well as improving the urban heat index. The fundamental  of greenery systems, which are thermal insulation, evapotranspiration, and shading effect, are also discussed. The benefits of greenery systems are including the improvement of stormwater management,  improvement of air quality, the reduction of sound pollution, the reduction of carbon dioxide, and the improvement of aesthetic building value. 
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  • 29 Oct 2020
Topic Review
Treatment Algorithm for Cancerous Wounds
Cancerous wound can be defined as non-healing compound chronic painful wound that arises from cancers and due to increased necrosis and infection, the quantity of malodorous discharge is highly increased. In advanced cancer stage the incidence of cancerous wounds is about 5%, and the estimated life expectancy is not more than 6 to 12 months. 
  • 5.6K
  • 11 Mar 2022
Topic Review
Flynn Effect
The Flynn effect is the substantial and long-sustained increase in both fluid and crystallized intelligence test scores that were measured in many parts of the world over the 20th century. When intelligence quotient (IQ) tests are initially standardized using a sample of test-takers, by convention the average of the test results is set to 100 and their standard deviation is set to 15 or 16 IQ points. When IQ tests are revised, they are again standardized using a new sample of test-takers, usually born more recently than the first. Again, the average result is set to 100. However, when the new test subjects take the older tests, in almost every case their average scores are significantly above 100. Test score increases have been continuous and approximately linear from the earliest years of testing to the present. For example, a study published in the year 2009 found that British children's average scores on the Raven's Progressive Matrices test rose by 14 IQ points from 1942 to 2008. Similar gains have been observed in many other countries in which IQ testing has long been widely used, including other Western European countries, Japan, and South Korea. There are numerous proposed explanations of the Flynn effect, as well as some skepticism about its implications. Similar improvements have been reported for semantic and episodic memory. Some research suggests that there may be an ongoing reversed Flynn effect, i.e. a decline in IQ scores, in Norway, Denmark, Australia, Britain, the Netherlands, Sweden, Finland, and German-speaking countries, a development which appears to have started in the 1990s, but in certain cases an apparent reversal is due to cultural changes making parts of intelligence tests obsolete. Meta-analyses indicate that overall, the Flynn effect continues either at the same rate or at a slower rate in developed countries.
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  • 03 Nov 2022
Topic Review
P53 Protein famliy
p53 and p73 are critical tumor suppressors that are often inactivated in human cancers through various mechanisms. Owing to their high structural homology, the proteins have many joined functions and recognize the same set of genes involved in apoptosis and cell cycle regulation. p53 is known as the ‘guardian of the genome’ and together with p73 forms a barrier against cancer development and progression. The TP53 is mutated in more than 50% of all human cancers and the germline mutations in TP53 predispose to the early onset of multiple tumors in Li–Fraumeni syndrome (LFS), the inherited cancer predisposition. In cancers where TP53 gene is intact, p53 is degraded. Despite the ongoing efforts, the treatment of cancers remains challenging. Presently, the endeavors focus on reactivating p53 exclusively, neglecting the potential of the restoration of p73 protein for cancer eradication. Taken that several small molecules reactivating p53 failed in clinical trials, there is a need to develop new treatments targeting p53 proteins in cancer. This review outlines the most advanced strategies to reactivate p53 and p73 and describes drug repurposing approaches for the efficient reinstatement of the p53 proteins for cancer therapy.
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  • 21 Oct 2020
Topic Review
Qt
Qt (pronounced "cute") is cross-platform software for creating graphical user interfaces as well as cross-platform applications that run on various software and hardware platforms such as Linux, Windows, macOS, Android or embedded systems with little or no change in the underlying codebase while still being a native application with native capabilities and speed. Qt is currently being developed by The Qt Company, a publicly listed company, and the Qt Project under open-source governance, involving individual developers and organizations working to advance Qt. Qt is available under both commercial licenses and open-source GPL 2.0, GPL 3.0, and LGPL 3.0 licenses.
  • 5.6K
  • 28 Nov 2022
Topic Review
Sustainable Tourism in Fiji
The tourism industry has evolved as a major contributor to economic development and employment creation globally. Over the past seven decades, the tourism industry has experienced growth in both developed and developing countries. Although tourism has significant economic benefits, it often compromises environmental quality. Thus, tourism sustainability becomes an important element in managing the industry. Tourism sustainability has emerged as a leading policy paradigm and is important because tourism is a significant contributor to carbon emissions worldwide.
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  • 02 Jun 2022
Topic Review
Trailer Connectors in North America
A number of standards prevail in North America, or parts of it, for trailer connectors, the electrical connectors between vehicles and the trailers they tow that provide a means of control for the trailers.
  • 5.6K
  • 28 Oct 2022
Topic Review
Flat Panel Display
Flat-panel displays are electronic viewing technologies used to enable people to see content (still images, moving images, text, or other visual material) in a range of entertainment, consumer electronics, personal computer, and mobile devices, and many types of medical, transportation and industrial equipment. They are far lighter and thinner than traditional cathode ray tube (CRT) television sets and video displays and are usually less than 10 centimetres (3.9 in) thick. Flat-panel displays can be divided into two display device categories: volatile and static. Volatile displays require that pixels be periodically electronically refreshed to retain their state (e.g., liquid-crystal displays (LCD)). A volatile display only shows an image when it has battery or AC mains power. Static flat-panel displays rely on materials whose color states are bistable (e.g., e-book reader tablets from Sony), and as such, flat-panel displays retain the text or images on the screen even when the power is off. As of 2016, flat-panel displays have almost completely replaced old CRT displays. In many 2010-era applications, specifically small portable devices such as laptops, mobile phones, smartphones, digital cameras, camcorders, point-and-shoot cameras, and pocket video cameras, any display disadvantages of flat-panels (as compared with CRTs) are made up for by portability advantages (thinness and lightweightness). Most 2010s-era flat-panel displays use LCD and/or LED technologies. Most LCD screens are back-lit as color filters are used to display colors. Flat-panel displays are thin and lightweight and provide better linearity and they are capable of higher resolution than typical consumer-grade TVs from earlier eras. The highest resolution for consumer-grade CRT TVs was 1080i; in contrast, many flat-panels can display 1080p or even 4K resolution. As of 2016, some devices that use flat-panels, such as tablet computers, smartphones and, less commonly, laptops, use touchscreens, a feature that enables users to select onscreen icons or trigger actions (e.g., playing a digital video) by touching the screen. Many touchscreen-enabled devices can display a virtual QWERTY or numeric keyboard on the screen, to enable the user to type words or numbers. A multifunctional monitor (MFM) is a flat-panel display that has additional video inputs (more than a typical LCD monitor) and is designed to be used with a variety of external video sources, such as VGA input, HDMI input from a VHS VCR or video game console and, in some cases, a USB input or card reader for viewing digital photos). In many instances, an MFM also includes a TV tuner, making it similar to a LCD TV that offers computer connectivity.
  • 5.6K
  • 25 Nov 2022
Topic Review
Effects of Planting Density on Tropical Fruit Crops
Plant density refers to the number of individual plants per unit of ground area. In an ideal plant population, the capability of the plant canopy to collect environmental resources, including radiation energy, water, and inorganic nutrients, can be improved. A dense plant population increases the competition between plants for resources, which results in limited resources being depleted. Additionally, improved canopy construction can lead to an optimal leaf area index that can boost photosynthetic ability through efficient solar radiation interception. High densities of plants encourage better productivity; lower densities, in general, allow for the harvesting of more large fruits, resulting in higher pricing on the fresh fruit market. Higher planting density is used for higher yields without increasing production costs.
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  • 31 Aug 2022
Topic Review
Tomatine
Tomatine (sometimes called tomatin or lycopersicin) is a glycoalkaloid, found in the stems and leaves of tomato plants, and in the fruits at much lower concentrations. Chemically pure tomatine is a white crystalline solid at standard temperature and pressure. Tomatine is sometimes confused with the glycoalkaloid solanine, which is found in potatoes.
  • 5.5K
  • 26 Oct 2022
Biography
Ravidas
Ravidas was an India n mystic poet-sant of the Bhakti movement of Sri Hari and his incarnations like Rama, Krishna such as Namdev, Meerabai and founder of Ravidassia sect during the 15th to 16th century CE.[1][2] Venerated as a guru (teacher) in the region of Uttar Pradesh, Rajasthan, Gujarat, Maharashtra, Madhya Pradesh and mainly Punjab and Haryana. He was a poet-saint, social reformer and a s
  • 5.5K
  • 15 Nov 2022
Topic Review
Family of Meghan, Duchess of Sussex
Members of the Markle and Ragland families have been related by marriage to the British royal family since the wedding of Meghan Markle and Prince Harry, Duke of Sussex, on May 19, 2018, when she became the Duchess of Sussex. The Markle (originally spelled Merckel) family is of German descent and originates in Alsace on the modern French–German border, and her ancestors moved to the United States in the 18th century; among her father's other ancestors are American settlers of English, Dutch, and Irish descent. Her mother is of African American descent and her early ancestors hailed from the U.S. state of Georgia.
  • 5.5K
  • 27 Nov 2022
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