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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 While the map's geography has been superseded by modern knowledge, its projection proved to be one of the most significant advances in the history of cartography, inspiring map historian Nordenskiöld to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
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.
  • 6.9K
  • 29 Aug 2023
Topic Review
Limit Point
In mathematics, a limit point (or cluster point or accumulation point) of a set [math]\displaystyle{ S }[/math] in a topological space [math]\displaystyle{ X }[/math] is a point [math]\displaystyle{ x }[/math] that can be "approximated" by points of [math]\displaystyle{ S }[/math] in the sense that every neighbourhood of [math]\displaystyle{ x }[/math] with respect to the topology on [math]\displaystyle{ X }[/math] also contains a point of [math]\displaystyle{ S }[/math] other than [math]\displaystyle{ x }[/math] itself. A limit point of a set [math]\displaystyle{ S }[/math] does not itself have to be an element of [math]\displaystyle{ S. }[/math] There is also a closely related concept for sequences. A cluster point or accumulation point of a sequence [math]\displaystyle{ (x_n)_{n \in \mathbb{N}} }[/math] in a topological space [math]\displaystyle{ X }[/math] is a point [math]\displaystyle{ x }[/math] such that, for every neighbourhood [math]\displaystyle{ V }[/math] of [math]\displaystyle{ x, }[/math] there are infinitely many natural numbers [math]\displaystyle{ n }[/math] such that [math]\displaystyle{ x_n \in V. }[/math] This definition of a cluster or accumulation point of a sequence generalizes to nets and filters. In contrast to sets, for a sequence, net, or filter, the term "limit point" is not synonymous with a "cluster/accumulation point"; by definition, the similarly named notion of a limit point of a filter (respectively, a limit point of a sequence, a limit point of a net) refers to a point that the filter converges to (respectively, the sequence converges to, the net converges to). The limit points of a set should not be confused with adherent points for which every neighbourhood of [math]\displaystyle{ x }[/math] contains a point of [math]\displaystyle{ S }[/math]. Unlike for limit points, this point of [math]\displaystyle{ S }[/math] may be [math]\displaystyle{ x }[/math] itself. A limit point can be characterized as an adherent point that is not an isolated point. Limit points of a set should also not be confused with boundary points. For example, [math]\displaystyle{ 0 }[/math] is a boundary point (but not a limit point) of set [math]\displaystyle{ \{ 0 \} }[/math] in [math]\displaystyle{ \R }[/math] with standard topology. However, [math]\displaystyle{ 0.5 }[/math] is a limit point (though not a boundary point) of interval [math]\displaystyle{ [0, 1] }[/math] in [math]\displaystyle{ \R }[/math] with standard topology (for a less trivial example of a limit point, see the first caption). This concept profitably generalizes the notion of a limit and is the underpinning of concepts such as closed set and topological closure. Indeed, a set is closed if and only if it contains all of its limit points, and the topological closure operation can be thought of as an operation that enriches a set by uniting it with its limit points.
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  • 25 Oct 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.
  • 6.9K
  • 05 Dec 2022
Topic Review Peer Reviewed
High-Speed Railway
Union Internationale des Chemins (UIC) defines the high-speed railway (HSR) as a high-speed railway system that contains the infrastructure and the rolling stock. The infrastructure can be newly built dedicated lines enabled for trains to travel with speed above 250 km/h or upgraded conventional lines with a speed up to 200 or even 220 km/h. HSR requires specially built trains with increased power to weight ratio and must have an in-cab signalling system as traditional signalling systems are incapable of above 200 km/h.
  • 6.9K
  • 18 Apr 2022
Topic Review
Superior Orders
Superior orders, also known as the Nuremberg defense or just following orders, is a plea in a court of law that a person, whether a member of the military, law enforcement, a firefighting force, or the civilian population, should not be considered guilty of committing actions that were ordered by a superior officer or official. The superior orders plea is often regarded as the complement to command responsibility. One of the most noted uses of this plea, or defense, was by the accused in the 1945–1946 Nuremberg trials, such that it is also called the "Nuremberg defense". The Nuremberg trials were a series of military tribunals, held by the main victorious Allies after World War II, most notable for the prosecution of prominent members of the political, military, and economic leadership of the defeated Nazi Germany. These trials, under the London Charter of the International Military Tribunal that established them, determined that the defense of superior orders was no longer enough to escape punishment, but merely enough to lessen punishment. Historically, the plea of superior orders has been used both before and after the Nuremberg Trials, with inconsistent rulings. Apart from the specific plea of superior orders, discussions about how the general concept of superior orders ought to be used, or ought not to be used, have taken place in various arguments, rulings and statutes that have not necessarily been part of "after the fact" war crimes trials, strictly speaking. Nevertheless, these discussions and related events help to explain the evolution of the specific plea of superior orders and the history of its usage.
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  • 08 Nov 2022
Topic Review
Kairos
Kairos (καιρός) is an Ancient Greek word meaning the right, critical, or opportune moment. The ancient Greeks had two words for time: chronos (χρόνος) and kairos. The former refers to chronological or sequential time, while the latter signifies a proper or opportune time for action. While chronos is quantitative, kairos has a qualitative, permanent nature. Kairos also means weather in Modern Greek. The plural, καιροί (kairoi (Ancient and Modern Greek)) means the times. Kairos is a term, idea, and practice that has been applied in several fields including classical rhetoric, modern rhetoric, digital media, Christian theology, and science.
  • 6.9K
  • 07 Oct 2022
Topic Review
Contact Lens Materials - A Materials Science Perspective
Contact lens materials are typically based on polymer- or silicone-hydrogel, with additional manufacturing technologies employed to produce the final lens. These processes are simply not enough to meet the increasing demands from CLs and the ever-increasing number of contact lens (CL) users. New materials and engineering offer increasing functionality or improved properties over previous generations.
  • 6.9K
  • 27 Jan 2022
Topic Review
La France Insoumise
La France Insoumise (pronounced [la fʁɑ̃s ɛ̃sumiz]; variously translated as "Unbowed France", "Unsubmissive France", or "Rebellious France") is a democratic socialist, left-wing populist political party in France , launched on 10 February 2016 by Jean-Luc Mélenchon, then a Member of the European Parliament (MEP) and former co-president of the Left Party (PG). It aims to implement the ecosocialist programme L'Avenir en commun (English: "A Shared Future"). The party nominated Mélenchon as its candidate for the presidential election of 2017. He came fourth in the first round, receiving 19.5% of the vote and failing to qualify for the second round by around 2%. After the legislative election of 2017, La France Insoumise formed a parliamentary group of 17 members of the National Assembly, with Mélenchon as the group's president. In the 2019 European Parliament election, it however only won six seats, below its expectations. The party uses the lower case Greek letter phi as its logotype.
  • 6.9K
  • 15 Nov 2022
Topic Review
Arthropod
Arthropods (/ˈɑːrθrəpɒd/, from grc ἄρθρον (arthron) 'joint', and πούς (pous) 'foot' (gen. ποδός)) are invertebrate animals having an exoskeleton, a segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and cuticle made of chitin, often mineralised with calcium carbonate. The arthropod body plan consists of segments, each with a pair of appendages. Arthropods are bilaterally symmetrical and their body possesses an external skeleton. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. Some species have wings. They are an extremely diverse group, with up to 10 million species. The haemocoel, an arthropod's internal cavity, through which its haemolymph – analogue of blood – circulates, accommodates its interior organs; it has an open circulatory system. Like their exteriors, the internal organs of arthropods are generally built of repeated segments. Their nervous system is "ladder-like", with paired ventral nerve cords running through all segments and forming paired ganglia in each segment. Their heads are formed by fusion of varying numbers of segments, and their brains are formed by fusion of the ganglia of these segments and encircle the esophagus. The respiratory and excretory systems of arthropods vary, depending as much on their environment as on the subphylum to which they belong. Arthropods use combinations of compound eyes and pigment-pit ocelli for vision. In most species, the ocelli can only detect the direction from which light is coming, and the compound eyes are the main source of information, but the main eyes of spiders are ocelli that can form images and, in a few cases, can swivel to track prey. Arthropods also have a wide range of chemical and mechanical sensors, mostly based on modifications of the many bristles known as setae that project through their cuticles. Similarly, their reproduction and development are varied; all terrestrial species use internal fertilization, but this is sometimes by indirect transfer of the sperm via an appendage or the ground, rather than by direct injection. Aquatic species use either internal or external fertilization. Almost all arthropods lay eggs, but many species give birth to live young after the eggs have hatched inside the mother, and a few are genuinely viviparous, such as aphids. Arthropod hatchlings vary from miniature adults to grubs and caterpillars that lack jointed limbs and eventually undergo a total metamorphosis to produce the adult form. The level of maternal care for hatchlings varies from nonexistent to the prolonged care provided by social insects. The evolutionary ancestry of arthropods dates back to the Cambrian period. The group is generally regarded as monophyletic, and many analyses support the placement of arthropods with cycloneuralians (or their constituent clades) in a superphylum Ecdysozoa. Overall, however, the basal relationships of animals are not yet well resolved. Likewise, the relationships between various arthropod groups are still actively debated. Today, Arthropods contribute to the human food supply both directly as food, and more importantly, indirectly as pollinators of crops. Some species are known to spread severe disease to humans, livestock, and crops.
  • 6.9K
  • 06 May 2023
Topic Review
List of Intel Pentium Microprocessors
The Intel Pentium brand refers to mainstream x86-architecture microprocessors from Intel. Processors branded Pentium Processor with MMX Technology (and referred to as Pentium MMX for brevity) are also listed here.
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  • 26 Oct 2022
Topic Review
Traditional and Novel Drying Techniques
       Drying is an ancient and unparalleled physical procedure of food conservation used for direct preparation of food products as well as for further processing in the food in Drying is an ancient and unparalleled physical procedure of food conservation used for direct preparation of food products as well as for further processing in the food industry. It has always been a valuable and common practice of conservation, ensuring the availability of food and medicinal products all year long dustry. It has always been a valuable and common practice of conservation, ensuring the availability of food and medicinal products all year long. Drying used to be natural and simple as the process was driven by solar energy. Nowadays, it became more sophisticated and complex as it uses a lot of equipment and the drying parameters are carefully examined and optimized at every stage of the process. Emerging new methods have been extensively studied in terms of chemical and biochemical changes in the product during the dehydration process. Drying not only preserves the product but also can have a positive impact on materials quality e.g., in spices, medicinal plants, herbs, bioactive enzymes, and nuts that can generate value-added compounds during drying [1,2].        The most important objectives of drying are: (i) preservation of fresh products, making them available whole year (ii) conversion of the fresh product into a dry one while maintaining or improving its final quality; (iii) reduction of the volume and weight of the product for an easier transportation and storage; and last but not least (iv) sustainable processing as the most popular drying methods use enormous quantities of energy at low efficiency [8]. Thus, the new drying techniques should provide advantages such as higher energy efficiency, better product quality, cost reduction, and lower environmental impact.  
  • 6.8K
  • 12 Oct 2020
Topic Review
Heaviest Trains
The heaviest trains in the world are freight trains hauling bulk commodities such as coal and iron ore. The weight of trains generally does not include the weight of the operating locomotives; this is not considered dead weight, so is not included. If for example a train had two locomotives operating and was simply hauling a third off line, this third locomotive would be included in the payload weight.
  • 6.8K
  • 01 Nov 2022
Topic Review
Human Genetic Clustering
Human genetic clustering is the degree to which human genetic variation can be partitioned into a small number of groups or clusters. A leading method of analysis uses mathematical cluster analysis of the degree of similarity of genetic data between individuals and groups in order to infer population structures and assign individuals to hypothesized ancestral groups. A similar analysis can be done using principal component analysis, and several recent studies deploy both methods. Analysis of genetic clustering examines the degree to which regional groups differ genetically, the categorization of individuals into clusters, and what can be learned about human ancestry from this data. There is broad scientific agreement that a relatively small fraction of human genetic variation occurs between populations, continents, or clusters. Researchers of genetic clustering differ, however, on whether genetic variation is principally clinal or whether clusters inferred mathematically are important and scientifically useful.
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  • 23 Nov 2022
Topic Review
Light-independent Reactions
The light-independent reactions, or dark reactions, of photosynthesis are chemical reactions that convert carbon dioxide and other compounds into glucose. These reactions occur in the stroma, the fluid-filled area of a chloroplast outside the thylakoid membranes. These reactions take the products (ATP and NADPH) of light-dependent reactions and perform further chemical processes on them.
  • 6.8K
  • 09 Nov 2022
Topic Review
Advantages and Disadvantages of Covalent Inhibitors
The formation of covalent bonds that target proteins can offer drugs diverse advantages in terms of target selectivity, drug resistance, and administration concentration. The most important factor for covalent inhibitors is the electrophile (warhead), which dictates selectivity, reactivity, and the type of protein binding (i.e., reversible or irreversible) and can be modified/optimized through rational designs. Furthermore, covalent inhibitors are becoming more and more common in proteolysis, targeting chimeras (PROTACs) for degrading proteins, including those that are currently considered to be ‘undruggable’.
  • 6.8K
  • 10 May 2023
Topic Review
Anomie
The concept of anomie is a sociological term that was introduced by French sociologist Emile Durkheim in his seminal work, "Suicide: A Study in Sociology," published in 1897. Anomie refers to a state of normlessness or a breakdown of social norms within a society. Durkheim used this concept to explain the social conditions that contribute to higher rates of suicide.
  • 6.8K
  • 25 Jan 2024
Topic Review
Perinatal Stem Cells
Perinatal tissues refer to tissues that are discarded at birth, such as the placenta, umbilical cord, cord blood, and amniotic fluid, and different stem and progenitor cell types can be isolated from these tissues. Regenerative medicine has found in the perinatal medical wastes one of the most promising sources of various cells and tissues for use in cell therapy and tissue engineering, both in experimental and clinical settings. The primary source of perinatal stem cells is cord blood. Cord blood has been a well-known source of hematopoietic stem/progenitor cells. Other perinatal tissues contain non-hematopoietic cells with potential therapeutic value. Indeed, in advanced perinatal cell therapy trials, mesenchymal stromal cells are the most commonly used.
  • 6.8K
  • 14 Jan 2021
Topic Review
Polymer 3D Printing
Polymer 3D printing is an emerging technology with recent research translating towards increased use in diverse industries. The polymer 3D printing process works by depositing a polymer in a directed fashion to form a completed part, generally through layer by layer deposition.  Polymer printing is advantageous because it enables printing low-cost functional parts with diverse properties and capabilities. An important aspect polymer 3D printing is the consideration of materials, processes, and design strategies that all influence a parts performance. Research in materials has led to the development of polymers with advantageous characteristics for mechanics and biocompatibility, with tuning of mechanical properties achieved by altering printing process parameters. Suitable polymer printing processes include extrusion, resin, and powder 3D printing, which enable directed material deposition for the design of advantageous and customized architectures.  Through careful consideration of material, process, and design it is possible to create a 3D printed polymer part of complex geometry that is tuned for a specific application on a per-print basis.
  • 6.8K
  • 23 Jun 2021
Topic Review
Green Star
In astronomy, a green star is a white or blueish star that appears greenish in some viewing conditions (see § Psychology below). Under typical viewing conditions, there are no greenish stars, because the color of a star is more or less given by a black-body spectrum. However, there are a few stars that appear greenish to some observers, due to the viewing conditions, for example the optical 'illusion' that a red object can make nearby objects look greenish (and vice versa). Some multiple star systems, such as Antares, have a bright reddish star where this contrast makes other stars in the system seem greenish.
  • 6.8K
  • 21 Nov 2022
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