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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.
  • 6.8K
  • 14 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.
  • 6.8K
  • 27 Jan 2022
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.
  • 6.8K
  • 26 Oct 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.
  • 6.8K
  • 06 May 2023
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
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.
  • 6.8K
  • 15 Nov 2022
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
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.
  • 6.8K
  • 05 Dec 2022
Topic Review
Human Mobility and Smart City
Human mobility, the movement of human beings in space and time, reflects the spatial-temporal characteristics of human behavior. With big data analytics, human mobility research can be used to facilitate smart city development, in multiple disciplines such as smart traffic, smart urban planning, smart health, smart safety, smart commerce, etc. A framework for linking international academic research and city-level management policy was established and applied to the case of Hong Kong. Literatures regarding human mobility research using big data are reviewed. These studies contribute to (1) discovering the spatial-temporal phenomenon, (2) identifying the difference in human behaviour or spatial attributes, (3) explaining the dynamic of mobility, and (4) applying to city management. Then, the application of the research to smart city development are scrutinised based on email queries to various governmental departments in Hong Kong. With further improvement in the practical value of data analytics and the utilization of data sourced from multiple sectors, paths to achieve smarter cities from policymaking perspectives are highlighted.
  • 6.8K
  • 06 Jun 2021
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
Synthesis of Fragrances via Cycloaddition or Formal Cycloaddition
Fragrances, short for fragrance ingredients, is a type of compounds with a sweet smell or pleasant odor that has wide applications in the fine chemical industry, especially in perfumes, cosmetics, detergents and food additives. Since the discovery of the Diels–Alder reaction, the cycloaddition of π reactants serves as one of the most powerful methods for the construction of carbocycles, which has a broad application in the fragrance industry.
  • 6.8K
  • 21 Jun 2022
Topic Review
Shotgun Wedding
A shotgun wedding is a wedding that is arranged to avoid embarrassment due to premarital sex possibly leading to an unintended pregnancy, rather than out of the desire of the participants. The phrase is a primarily American colloquialism, termed as such based on a stereotypical scenario where the father of the pregnant bride-to-be threatens the reluctant groom with a shotgun to ensure that he follows through with the wedding.
  • 6.8K
  • 25 Nov 2022
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
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.
  • 6.8K
  • 29 Aug 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
Frequency
Frequency is the number of occurrences of a repeating event per unit of time. It is also referred to as temporal frequency, which emphasizes the contrast to spatial frequency and angular frequency. Frequency is measured in units of hertz (Hz) which is equal to one occurrence of a repeating event per second. The period is the duration of time of one cycle in a repeating event, so the period is the reciprocal of the frequency. For example: if a newborn baby's heart beats at a frequency of 120 times a minute (2 hertz), its period, T, — the time interval between beats—is half a second (60 seconds divided by 120 beats). Frequency is an important parameter used in science and engineering to specify the rate of oscillatory and vibratory phenomena, such as mechanical vibrations, audio signals (sound), radio waves, and light.
  • 6.8K
  • 16 Nov 2022
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
Topic Review
Anti Urination Devices in Norwich
Anti urination devices were a form of hostile architecture installed in Norwich and the surrounding area in the late 19th century to discourage public urination. The overcrowded and narrow streets of the city centre and a lack of public toilets led to men urinating against the side of buildings, but the installation of new public urinals to address the issue was delayed by disputes over where they were to be sited. Anti urination devices were built in places which suffered particular problems with public urination, and were intended to discourage men from urinating at that spot. Most were built of sloped or curved stone, flint or concrete, and were shaped such that anyone attempting to urinate against the wall would need to stand well away from the wall in public view, hopefully discouraging them from doing so. The slope of the structure meant that should anyone still attempt to urinate against it, the stream of urine would be deflected back onto their feet and legs. A few instead consisted of a spiked metal bar positioned across a corner at the height of a typical man's groin, and were intended to dissuade men from approaching the corner with their genitals exposed. Following improved public toilet provision from the 1890s onwards, the problems caused by the lack of urinals became less of an issue, and anti urination devices ceased to be installed. Although most metal examples were removed during the Second World War, and many others have been demolished in subsequent years, around 30 remain in place in central Norwich with further surviving examples in other parts of East Anglia.
  • 6.8K
  • 07 Oct 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
Emgrand EC7
The Geely Emgrand or originally, the Emgrand EC7 is a compact car produced by the Emgrand division of the Chinese automaker Geely. After the discontinuation of the "Emgrand" brand, Emgrand EC7 was renamed to Geely Emgrand in 2014. The second generation Geely Emgrand was shown to public in 2014 Beijing Auto Show.
  • 6.8K
  • 23 Nov 2022
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