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Topic Review
Black Belt (U.S. Region)
The Black Belt is a region of the Southern United States. The term originally described the prairies and dark fertile soil of central Alabama and northeast Mississippi. Because this area in the 19th century was historically developed for cotton plantations based on enslaved African American labor, the term became associated with these conditions. It was generally applied to a much larger agricultural region in the Southern United States, which was characterized by a history of cotton plantation agriculture in the 19th century and a high percentage of African Americans outside metropolitan areas. The enslaved peoples were freed after the American Civil War, and many continued to work in agriculture afterward. Their descendants make up much of the African-American population of the United States. During the first half of the 19th Century, as many as one million enslaved Africans were transported through sales in the domestic slave trade to the Deep South in a forced migration to work as laborers for the region's cotton plantations. After having lived enslaved for several generations in the area, many remained as rural workers, tenant farmers and sharecroppers after the Civil War and emancipation. Beginning in the early 20th century and up to 1970, a total of six million black people left the South in the Great Migration to find work and other opportunities in the industrial cities of the Northeast, Midwest, and West. Because of relative isolation and lack of economic development, the rural communities in the Black Belt have historically faced acute poverty, rural exodus, inadequate education programs, low educational attainment, poor health care, urban decay, substandard housing, and high levels of crime and unemployment. In December 2017, the Special Rapporteur of the Office of the United Nations High Commissioner for Human Rights declared that Alabama was the most impoverished area in the developed world. Given the history of decades of racial segregation into the late 20th century, African-American residents have been the most disproportionately affected, although these problems apply broadly to all ethnic groups in the rural Black Belt. The region and its boundaries have varying definitions, but it is generally considered a band through the center of the Deep South, although stretching from as far north as Delaware to as far west as East Texas.
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  • 31 Oct 2022
Topic Review
Rolls-Royce Phantom VII
The Rolls-Royce Phantom VII is a full-sized luxury saloon car made by Rolls-Royce Motor Cars. Launched in 2003, it was the first Rolls-Royce developed and introduced after BMW purchased the right to use the Rolls-Royce name and logo in 1998. It is credited with successfully reviving the Rolls-Royce brand and restoring Rolls-Royce's reputation as a maker of luxury cars. The Phantom Drophead Coupé and Phantom Coupé are two-door derivatives of the Phantom launched in 2007 and 2008, respectively. From 2003 until the launch of the smaller Ghost in 2009, the Phantom was the only car produced by Rolls-Royce. The Phantom acted as the company's flagship model, but was less exclusive than all previous Phantoms (none of which surpassed the 600 per year).
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  • 05 Dec 2022
Topic Review
List of Academic Journals by Preprint Policy
This is a list of academic journals by their submission policies regarding the use of preprints prior to publication, such as the arXiv, and bioRxiv. Journals focusing on physics and mathematics are excluded because they routinely accept manuscripts that have been posted to preprint servers. Publishers' policies on self-archiving (including preprint versions) can also be found at SHERPA/RoMEO.
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  • 29 Dec 2022
Topic Review
Key Oil Palm Pests and Their Managements
Oil palm, Elaeis guineensis Jacq. (Arecales: Arecaceae), is a multipurpose plantation crop that is extensively grown in the humid tropics across Asia, Africa and the Americas for palm oil and other uses such as sauces, soap, wine, fertilizer (ashes), roofing (leaves), building material (trunk), medicines (roots), and ornamental purposes. Oil palm is attacked by numerous insect species globally, including defoliators, leaf/fruit scrapers, borers and sap feeders. The common oil palm pest management methods include synthetic insecticides, biopesticides, semiochemical lures, cultural practices, and integrated approaches.
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  • 04 Jan 2023
Topic Review
Perinuclear Anti-Neutrophil Cytoplasmic Antibodies (P-ANCA)
Perinuclear anti-neutrophilic cytoplasmic antibodies (P-ANCA) recognize heterogeneous antigens, including myeloperoxidase (MPO), lactoferrin, elastase, cathepsin-G and bactericidal/permeability-increasing protein. Although P-ANCA have diagnostic utility in vasculitides, they may also be found in patients with various other systemic autoimmune rheumatic diseases (SARDs). Nevertheless, the clinical significance and the targets recognized by P-ANCA in such patients remain unclear. For this purpose, herein we investigated the occurrence of ANCA-related antigenic specificities in 82 P-ANCA-positive sera by multiplex ELISA, as well as their association with other autoantibodies. The P-ANCA-positive sera corresponded to patients with vasculitides (n = 24), systemic lupus erythematosus (n = 28), antiphospholipid syndrome (n = 5), Sjögren’s syndrome (n = 7), rheumatoid arthritis (n = 3), systemic scleroderma (n = 1), sarcoidosis (n = 1) and Hashimoto′s thyroiditis (n = 13). In most P-ANCA-positive patients studied (51/82, 62.3%), these autoantibodies occurred in high titers (>1:160). The analysis of P-ANCA-positive sera revealed reactivity to MPO in only 50% of patients with vasculitides, whereas it was infrequent in the other disease groups studied. Reactivity to other P-ANCA-related autoantigens was also rarely detected. Our findings support that high P-ANCA titers occur in SARD. The P-ANCA-positive staining pattern is associated with MPO specificity in vasculitides, while in other autoimmune diseases, it mostly involves unknown autoantigens. 
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  • 27 Aug 2021
Topic Review
Vishvakarman
Vishvakarman (Sanskrit: विश्वकर्मन्, Viśvakarman; lit. "all creating") is the Personification of ultimate reality and deity of the creative power. He is believed to be one of the ancient architect or engineer who created and taught building of ancient monuments, architectures in Bharat, now India. According to the Rigveda It/He is considered to be the architect, divine engineer of universe from before the advent of time.
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  • 29 Sep 2022
Topic Review
Intel MCS-51
The Intel MCS-51 (commonly termed 8051) is a single chip microcontroller (MCU) series developed by Intel in 1980 for use in embedded systems. The architect of the Intel MCS-51 instruction set was John H. Wharton. Intel's original versions were popular in the 1980s and early 1990s and enhanced binary compatible derivatives remain popular today. It is an example of a complex instruction set computer, and has separate memory spaces for program instructions and data. Intel's original MCS-51 family was developed using N-type metal-oxide-semiconductor (NMOS) technology like its predecessor Intel MCS-48, but later versions, identified by a letter C in their name (e.g., 80C51) use complementary metal–oxide–semiconductor (CMOS) technology and consume less power than their NMOS predecessors. This made them more suitable for battery-powered devices. The family was continued in 1996 with the enhanced 8-bit MCS-151 and the 8/16/32-bit MCS-251 family of binary compatible microcontrollers. While Intel no longer manufactures the MCS-51, MCS-151 and MCS-251 family, enhanced binary compatible derivatives made by numerous vendors remain popular today. Some derivatives integrate a digital signal processor (DSP). Beyond these physical devices, several companies also offer MCS-51 derivatives as IP cores for use in field-programmable gate array (FPGA) or application-specific integrated circuit (ASIC) designs.
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  • 14 Oct 2022
Topic Review
Antiparasitic Mebendazole for the Treatment of Brain Cancers
Cancer ranks as a leading cause of death and a significant barrier to increasing life expectancy in every country. According to estimates from the World Health Organization (WHO) in 2019, cancer is the first or second leading cause of death before age 70 in 112 of 183 countries and ranks third or fourth in 23 countries. Tumor treatments usually consist of chemotherapy, radiotherapy, surgery, targeted therapy, immunotherapy, and endocrine therapy that can be used individually or in combination, depending on the stage and type of tumor and diagnosis. Several factors reduce the practical improvement of a cancer patient’s prognosis. Drug-untreatable targets, chemoresistance, tumor heterogeneity, and metastases formation are significant barriers to the effective cure of cancer patients. Despite intense preclinical and clinical research efforts, the survival rate of patients suffering from the most aggressive cancer types has not yet improved, mainly due to therapeutic failure. Moreover, nearly all anticancer medications on the market have serious adverse effects; therefore, new, safer anticancer drugs are desirable.
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  • 19 Jan 2023
Topic Review
Acoustic Extinguishing
In the fire-extinguishing process, in principle, one of the components in the fire tetrahedron must be removed. For example, a natural gas fire occurring on a stovetop burner can be extinguished in various ways: Eliminating the fuel source by shutting off the gas supply may be the first option. Another option is to completely cover the flame to block any oxidizer that is present, such as oxygen in the air, during combustion.
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  • 25 Mar 2022
Topic Review
Microalgae/Cyanobacteria in Biodegradation of Plastics
Cyanobacteria (e.g., Synechocystis sp. PCC 6803, and Synechococcus elongatus PCC 7942), which are photosynthetic prokaryotes and were previously identified as blue-green algae, are currently under close attention for their abilities to capture solar energy and the greenhouse gas carbon dioxide for the production of high-value products. In the last few decades, these microorganisms have been exploited for different purposes (e.g., biofuels, antioxidants, fertilizers, and ‘superfood’ production). Microalgae (e.g., Chlamydomonas reinhardtii, and Phaeodactylum tricornutum) are also suitable for environmental and biotechnological applications based on the exploitation of solar light. In recent years, several studies have been targeting the utilization of microorganisms for plastic bioremediation. Among the different phyla, the employment of wild-type or engineered cyanobacteria may represent an interesting, environmentally friendly, and sustainable option (e.g., mismanaged plastics as source of carbons for their cultivation: the connection between their simultaneous utilization for biofuels or chemicals production and microplastics consumption on the surface of basins).
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  • 05 Jan 2021
Topic Review
Mercator 1569 World Map
The Mercator world map of 1569 is titled Nova et Aucta Orbis Terrae Descriptio ad Usum Navigantium Emendate Accommodata (Renaissance Latin for "New and more complete representation of the terrestrial globe properly adapted for use in navigation"). The title shows that Gerardus Mercator aimed to present contemporary knowledge of the geography of the world and at the same time 'correct' the chart to be more useful to sailors. This 'correction', whereby constant bearing sailing courses on the sphere (rhumb lines) are mapped to straight lines on the plane map, characterizes the Mercator projection. While the map's geography has been superseded by modern knowledge, its projection proved to be one of the most significant advances in the history of cartography, inspiring map historian Nordenskiöld to write "The master of Rupelmonde stands unsurpassed in the history of cartography since the time of Ptolemy." The projection heralded a new era in the evolution of navigation maps and charts and it is still their basis. The map is inscribed with a great deal of text. The framed map legends (or cartouches) cover a wide variety of topics: a dedication to his patron and a copyright statement; discussions of rhumb lines, great circles and distances; comments on some of the major rivers; accounts of fictitious geography of the north pole and the southern continent. The full Latin texts and English translations of all the legends are given below. Other minor texts are sprinkled about the map. They cover such topics as the magnetic poles, the prime meridian, navigational features, minor geographical details, the voyages of discovery and myths of giants and cannibals. These minor texts are also given below. A comparison with world maps before 1569 shows how closely Mercator drew on the work of other cartographers and his own previous works, but he declares (Legend 3) that he was also greatly indebted to many new charts prepared by Portuguese and Spanish sailors in the portolan tradition. Earlier cartographers of world maps had largely ignored the more accurate practical charts of sailors, and vice versa, but the age of discovery, from the closing decade of the fifteenth century, stimulated the integration of these two mapping traditions: Mercator's world map is one of the earliest fruits of this merger.
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  • 22 Nov 2022
Topic Review
Hungarian Soviet Republic
The Hungarian Soviet Republic, literally the Republic of Councils in Hungary (Hungarian: Magyarországi Tanácsköztársaság), also known as the Hungarian Socialist Federative Soviet Republic (Hungarian: Magyarországi Szocialista Szövetséges Tanácsköztársaság) was a short-lived (133 days) communist rump state. When the Republic of Councils in Hungary was established in 1919, it controlled approximately 23% of the territory of Hungary's classic pre-World War I territories (325 411 km2). It was the successor of the first Hungarian People's Republic and lasted from only 21 March to 1 August 1919. Though the de jure leader of the Hungarian Soviet Republic was president Sándor Garbai, the de facto power was in the hands of foreign minister Béla Kun, who maintained direct contact with Lenin via radiotelegraph. It was Lenin who gave the direct orders and advice to Béla Kun via constant radio communication with the Kremlin. It was the second socialist state in the world to be formed, preceded by only the October Revolution in Russia which brought the Bolsheviks to power. The Hungarian Republic of Councils had military conflicts with the Kingdom of Romania, the Kingdom of Serbs, Croats and Slovenes and the evolving Czechoslovakia. It ended on 1 August 1919 when Hungarians sent representatives to negotiate their surrender to the Romanian forces. Due to the mistranslation, it is often referred to as "Hungarian Soviet republic" in English sources, despite the literal name "Republic of Councils in Hungary" was chosen for the purpose to avoid any strong ethnic connotation with Hungarian people, and express the Proletarian internationalist doctrine of the new Communist regime.
  • 6.9K
  • 20 Oct 2022
Topic Review
Cybersecurity Economics
Cybersecurity economics can be defined as a field of research that utilizes a socio-technical perspective to investigate economic aspects of cybersecurity such as budgeting, information asymmetry, governance, and types of goods and services, to provide sustainable policy recommendations, regulatory options, and practical solutions that can substantially improve the cybersecurity posture of the interacting agents in the open socio-technical systems.   
  • 6.9K
  • 15 Dec 2021
Topic Review
Residential Electricity Consumption of Seoul
This entry aims to determine the relationship between residential electricity consumption and other factors by analyzing the correlation and multiple regression between residential electricity consumption and three variables which are known as the factors affecting residential electricity consumption.  
  • 6.9K
  • 03 Nov 2020
Topic Review
Ecliptic Coordinate System
The ecliptic coordinate system is a celestial coordinate system commonly used for representing the apparent positions, orbits, and pole orientations of Solar System objects. Because most planets (except Mercury) and many small Solar System bodies have orbits with only slight inclinations to the ecliptic, using it as the fundamental plane is convenient. The system's origin can be the center of either the Sun or Earth, its primary direction is towards the vernal (March) equinox, and it has a right-hand convention. It may be implemented in spherical or rectangular coordinates.
  • 6.9K
  • 19 Oct 2022
Topic Review
Rainbow Serpent
The Rainbow Serpent or Rainbow Snake is a common deity (also known as Wagyl, Wuagyl, etc.) often seen as a creator god and a common motif in the art and religion of Aboriginal Australia . It is named for the identification between the shape of a rainbow and that of a snake. Some scholars believe that the link between snake and rainbow suggests the cycle of the seasons, for example blue (winter), red (summer), yellow (spring) and orange (autumn), and the importance of water in human life. When the rainbow is seen in the sky, it is said to be the Rainbow Serpent moving from one waterhole to another, and the divine concept explained why some waterholes never dried up when drought struck. There are innumerable names and stories associated with the serpent, all of which communicate the significance and power of this being within Aboriginal traditions. It is viewed as a giver of life, through its association with water, but can be a destructive force if angry. The Rainbow Serpent is one of the most common and well known Aboriginal stories, and is of great importance to Aboriginal society. The Rainbow Serpent is one of the oldest continuing religious beliefs in the world and continues to be a cultural influence today.
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  • 14 Oct 2022
Topic Review
Morel Cultivation Industry in China
Morels are one of the most highly prized edible and medicinal mushrooms worldwide. Therefore, historically, there has been a large international interest in their cultivation. Numerous ecological, physiological, genetic, taxonomic, and mycochemical studies have been previously developed. At the beginning of 21th century, China finally achieved artificial cultivation and started a high-scale commercial development in 2012. Due to its international interest, its cultivation scale and area expanded rapidly in this country. However, along with the massive industrial scale, a number of challenges, including the maintenance of steady economic profits, arise. In order to contribute to the solution of these challenges, formal research studying selection, species recognition, strain aging, mating type structure, life cycle, nutrient metabolism, growth and development, and multi-omics has recently been boosted.
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  • 29 Aug 2023
Topic Review
ZED Depth Sensors
The ZED depth sensor is considered as one of the world's fastest depth camera. It is composed of stereo cameras  with dual 4 mega-pixel RGB sensors. 
  • 6.9K
  • 09 Mar 2022
Topic Review
Revolutions of 1848
The Revolutions of 1848, known in some countries as the Springtime of the Peoples or the Springtime of Nations, were a series of political upheavals throughout Europe in 1848. It remains the most widespread revolutionary wave in European history. The revolutions were essentially democratic and liberal in nature, with the aim of removing the old monarchical structures and creating independent nation-states. The revolutions spread across Europe after an initial revolution began in France in February. Over 50 countries were affected, but with no significant coordination or cooperation among their respective revolutionaries. Some of the major contributing factors were widespread dissatisfaction with political leadership, demands for more participation in government and democracy, demands for freedom of the press, other demands made by the working class, the upsurge of nationalism, the regrouping of established government forces, and the European Potato Failure, which triggered mass starvation, migration, and civil unrest. The uprisings were led by temporary coalitions of reformers, the middle classes ("the bourgeoisie") and workers. However, the coalitions did not hold together for long. Many of the revolutions were quickly suppressed; tens of thousands of people were killed, and many more were forced into exile. Significant lasting reforms included the abolition of serfdom in Austria and Hungary, the end of absolute monarchy in Denmark, and the introduction of representative democracy in the Netherlands. The revolutions were most important in France, the Netherlands, Italy, the Austrian Empire, and the states of the German Confederation that would make up the German Empire in the late 19th and early 20th century.
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  • 05 Dec 2022
Topic Review
Normal Strain
In physics, deformation is the continuum mechanics transformation of a body from a reference configuration to a current configuration. A configuration is a set containing the positions of all particles of the body. A deformation can occur because of external loads, intrinsic activity (e.g. muscle contraction), body forces (such as gravity or electromagnetic forces), or changes in temperature, moisture content, or chemical reactions, etc. Strain is related to deformation in terms of relative displacement of particles in the body that excludes rigid-body motions. Different equivalent choices may be made for the expression of a strain field depending on whether it is defined with respect to the initial or the final configuration of the body and on whether the metric tensor or its dual is considered. In a continuous body, a deformation field results from a stress field due to applied forces or because of some changes in the temperature field of the body. The relation between stress and strain is expressed by constitutive equations, e.g., Hooke's law for linear elastic materials. Deformations which cease to exist after the stress field is removed are termed as elastic deformation. In this case, the continuum completely recovers its original configuration. On the other hand, irreversible deformations remain. They exist even after stresses have been removed. One type of irreversible deformation is plastic deformation, which occurs in material bodies after stresses have attained a certain threshold value known as the elastic limit or yield stress, and are the result of slip, or dislocation mechanisms at the atomic level. Another type of irreversible deformation is viscous deformation, which is the irreversible part of viscoelastic deformation. In the case of elastic deformations, the response function linking strain to the deforming stress is the compliance tensor of the material.
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  • 21 Oct 2022
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