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Topic Review
HMG-CoA-Reductase
3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoAR) is an enzyme involved in the biosynthesis of cholesterol and an important target in the treatment of hypercholesterolemia.
  • 11.4K
  • 29 Oct 2020
Topic Review
Mosasaurus
Mosasaurus (/ˌmoʊzəˈsɔːrəs/; "lizard of the Meuse River") is the type genus (defining example) of the mosasaurs, an extinct group of aquatic squamate reptiles. It lived from about 82 to 66 million years ago during the Campanian and Maastrichtian stages of the Late Cretaceous. The earliest fossils of Mosasaurus known to science were found as skulls in a chalk quarry near the Dutch city of Maastricht in the late 18th century, which were initially thought to have been the bones of crocodiles or whales. One skull discovered around 1780, and which was seized by France during the French Revolutionary Wars for its scientific value, was famously nicknamed the "great animal of Maastricht". In 1808, naturalist Georges Cuvier concluded that it belonged to a giant marine lizard with similarities to monitor lizards but otherwise unlike any known living animal. This concept was revolutionary at the time and helped support the then-developing ideas of extinction. Cuvier did not designate a scientific name for the new animal, and this was done by William Daniel Conybeare in 1822 when he named it Mosasaurus in reference to its origin in fossil deposits near the Meuse River. The exact affinities of Mosasaurus as a squamate remain controversial, and scientists continue to debate whether its closest living relatives are monitor lizards or snakes. Traditional interpretations have estimated the maximum length of the largest species, M. hoffmannii, to be up to 17.1 meters (56 ft), making it one of the largest mosasaurs, although some scientists consider this an overestimation with recent estimates suggesting a length closer to 13 meters (43 ft). The skull of Mosasaurus was equipped with robust jaws capable of swinging back and forth and strong muscles capable of powerful bites using dozens of large teeth adapted for cutting prey. Its four limbs were shaped into robust paddles to steer the animal underwater. Its tail was long and ended in a downward bend and a paddle-like fluke. Mosasaurus was a predator possessing excellent vision to compensate for its poor sense of smell, and a high metabolic rate suggesting it was endothermic ("warm-blooded"), an adaptation only found in mosasaurs among squamates. There is considerable morphological variability across the currently-recognized species in Mosasaurus—from the robustly-built M. hoffmannii to the slender and serpentine M. lemonnieri—but an unclear diagnosis (description of distinguishing features) of the type species M. hoffmannii led to a historically problematic classification. As a result, more than fifty different species have been attributed to the genus in the past. A redescription of the type specimen in 2017 helped resolve the taxonomy issue and confirmed at least five species to be within the genus. Another five species still nominally classified within Mosasaurus are planned to be reassessed in a future study. Fossil evidence suggests Mosasaurus inhabited much of the Atlantic Ocean and the seaways adjacent to it. Mosasaurus fossils have been found in places as diverse as North and South America, Europe, Africa, Western Asia, and Antarctica. This distribution encompassed a wide range of oceanic climates including tropical, subtropical, temperate, and subpolar climates. Mosasaurus was a common large predator in these oceans and was positioned at the top of the food chain. Paleontologists believe its diet would have included virtually any animal; it likely preyed on bony fish, sharks, cephalopods, birds, and other marine reptiles including sea turtles and other mosasaurs. It likely preferred to hunt in open water near the surface. From an ecological standpoint, Mosasaurus probably had a profound impact on the structuring of marine ecosystems; its arrival in some locations such as the Western Interior Seaway in North America coincides with a complete turnover of faunal assemblages and diversity. Mosasaurus faced competition with other large predatory mosasaurs such as Prognathodon and Tylosaurus—which were known to feed on similar prey—though they were able to coexist in the same ecosystems through niche partitioning. There were still conflicts among them, as an instance of Tylosaurus attacking a Mosasaurus has been documented. Several fossils document deliberate attacks on Mosasaurus individuals by members of the same species. Infighting likely took place in the form of snout grappling, similarly seen in modern crocodiles today.
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  • 01 Dec 2022
Topic Review
Southern European People
Southern European people are a pan-ethnic group, or multi-ethnic regional grouping, and the inhabitants of Southern Europe. South or Southern Europeans can usually trace back full or partial heritage to Greece, Italy, Spain , Portugal, as well as nations bordering with, or ethnoculturally related to, the region. As the pan-ethnic group is also culturally defined, rather than exclusively a geographical category, it often includes peoples inhabiting areas that are, at times, considered outside of the region. This can include people with heritage from Southern France, the Mediterranean islands of Corsica (also part of France ), Malta and Cyprus (geographically part of West Asia), Southeastern Europe's Albania and European Turkey. There are also descriptions of Southern Europeans which include ancestry from other nations in Southeast Europe, and countries of the South Slavs, particularly in diasporic identification. As Slavs, they are also often identified as Eastern Europeans. There is a large Southern European diaspora, with significant concentrations in the United Kingdom, North America (Southern European Americans and Canadians), and Southern European Australians in Oceania. Other subgroups of Europeans include Eastern European people and Northwestern European people.
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  • 29 Sep 2022
Topic Review
Clouding of Consciousness
Clouding of consciousness (also known as brain fog or mental fog) is when a person is slightly less wakeful or aware than normal. They are not as aware of time or their surroundings and find it difficult to pay attention. People describe this subjective sensation as their mind being "foggy".
  • 11.4K
  • 21 Nov 2022
Topic Review
Sustainable Business Models
Over the years, researchers have presented different concepts regarding business models. There is no unanimity, but there is a general agreement that a business model is the representation of how a company conducts its business. Subsequently, interest in the topic has increased and has come to be considered by companies that, driven to incorporate a positive contribution to sustainability into their values, began to face economic development that considers social and environmental aspects instead of worrying only about profit for the shareholders.
  • 11.4K
  • 19 Apr 2022
Topic Review Peer Reviewed
Prefabricated Building Systems—Design and Construction
Modern Methods of Construction with Offsite Manufacturing is an advancement from prefabricated technologies that existed for decades in the construction industry, and is a platform to integrate various disciplines into providing a more holistic solution. Due to the rapid speed of construction, reduced requirement of labour and minimised work on site, offsite manufacturing and prefabricated building systems are becoming more popular, and perhaps a necessity for the future of the global construction industry. The approach to the design and construction of prefab building systems demands a thorough understanding of their unique characteristics.
  • 11.3K
  • 13 Apr 2022
Topic Review
Vascular bundles
Vascular bundles play important roles in transporting nutrients, growth signals, amino acids, and proteins between aerial and underground tissues. 
  • 11.3K
  • 26 Feb 2021
Topic Review
A Strategic Information System Planning and Strategy-As-Practice Perspective
Strategic information system planning (SISP) is a central process that enables organizations to identify the strategic alignment of their IT portfolio to achieve their business needs and objectives. The extant SISP literature has focused on theoretical and processual aspects and has left methodological ambiguity about how SISP is practiced. Strategic information system planning (SISP) becomes central for any business when an organization faces an inflection point concerning its information system.
  • 11.3K
  • 15 Jun 2022
Topic Review
Surface Cleaning Methods
It is difficult to avoid surface contaminants in the processes of integrated circuit manufacturing, optical elements processing and additive forging. The presence of surface contaminants will bring great problems to above process. For example, in large- scale integrated circuits manufacturing, the submicron contaminants on silicon wafer surface will cause defects in the chip directly [1]. And in the manufacture of optical elements, the quality of the cleaned surface will directly affect the damage resistance of optical elements [2], and the presence of surface contaminants will affect its service life [3]. Similarly, during the additive forging process, the surface contaminants will affect the interface healing state of the substrate and ultimately affect its bonding performance. However, surface contaminants can be removed effectively by a suitable surface cleaning method, so surface cleaning is of great significance to solve the above problems.
  • 11.3K
  • 29 Oct 2020
Topic Review
Hat Puzzle
Hat puzzles are logic problems that date back to as early as 1961. Such hat puzzles, frequently contextualized as prisoners and hats puzzles, are induction puzzles (a kind of logic puzzle) that involve reasoning about the actions of other people, drawing in aspects of Game theory sometimes called the hierarchy of beliefs. There are many variations, but the central theme remains the same. A number of players are each wearing a hat, which may be of various specified colours. Players can see the colours of at least some other players' hats, but not that of their own. With highly restricted communication or none, some of the players must guess the colour of their hat. The problem is to find a strategy for the players to determine the colours of their hats based on the hats they see and what the other players do. In some versions, they compete to be the first to guess correctly; in others, they can work out a strategy beforehand to cooperate and maximize the probability of correct guesses. One variation received some new publicity as a result of Todd Ebert's 1998 Ph.D. thesis at the University of California, Santa Barbara. It is a strategy question about a cooperative game, which has connections to algebraic coding theory.
  • 11.3K
  • 24 Oct 2022
Biography
Friedrich Nietzsche
Friedrich Wilhelm Nietzsche (/ˈniːtʃə, ˈniːtʃi/;[1] German: [ˈfʁiːdʁɪç ˈvɪlhɛlm ˈniːtʃə] or [ˈniːtsʃə];[2][3] 15 October 1844 – 25 August 1900) was a German philosopher, cultural critic, composer, poet, writer, and philologist whose work has exerted a profound influence on modern intellectual history. He began his career as a classical philologist before turning to phil
  • 11.3K
  • 06 Dec 2022
Topic Review
Mopar Automatic Transmission Fluid
Mopar branded automatic transmission fluids (ATF) have been available for use in Chrysler fully automatic transmissions since 1953. Other Mopar branded fluids for their Fluid Drive semi-automatic transmissions were available as early as 1938. Chrysler used General Motors (GM) automatic transmission fluid specifications from 1952 through 1966 and marketed them under the Mopar brand name. In 1966, Chrysler began releasing their own automatic transmission fluid specifications. Chrysler licenses their ATF specifications to companies which manufacture the fluid and sell it under their own brand names. Not all Chrysler fluids are licensed for reselling under another brand name. All licensed Chrysler fluids must have a license number on the container. If no license number is found, the fluid may not be Chrysler approved and the fluid cannot be guaranteed to meet Chrysler specifications. Chrysler, like many automobile manufacturers, uses transmissions sourced from other suppliers or transmission manufacturers around the world; these transmissions are not manufactured by Chrysler. Many of these automatic transmissions use unique fluids that might not be shown on this page.
  • 11.3K
  • 07 Nov 2022
Topic Review
Records Continuum Model
The Records Continuum Model (RCM) was created in the 1990s by Monash University academic Frank Upward with input from colleagues Sue McKemmish and Livia Iacovino as a response to evolving discussions about the challenges of managing digital records and archives in the discipline of Archival Science. The RCM was first published in Upward’s 1996 paper "Structuring the Records Continuum – Part One: Postcustodial principles and properties". Upward describes the RCM within the broad context of a continuum where activities and interactions transform documents into records, evidence and memory that are used for multiple purposes over time. Upward places the RCM within a post-custodial, postmodern and structuration conceptual framework. Australian academics and practitioners continue to explore, develop and extend the RCM and records continuum theory, along with international collaborators, via the Records Continuum Research Group (RCRG) at Monash University.
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  • 09 Nov 2022
Topic Review
Protein dynamics
Protein dynamics is a highly complex phenomenon comprising numerous contributions from motions with different mechanisms of action and happening with diverse timescales and amplitudes that highly depend on the system and the local environment.
  • 11.3K
  • 01 Nov 2020
Topic Review
Red Algae
Red algae, or Rhodophyta (/roʊˈdɒfɪtə/, /ˌroʊdəˈfaɪtə/; from grc ῥόδον (rhódon) 'rose', and φυτόν (phutón) 'plant'), are one of the oldest groups of eukaryotic algae. The Rhodophyta also comprises one of the largest phyla of algae, containing over 7,000 currently recognized species with taxonomic revisions ongoing. The majority of species (6,793) are found in the Florideophyceae (class), and mostly consist of multicellular, marine algae, including many notable seaweeds. Red algae are abundant in marine habitats but relatively rare in freshwaters. Approximately 5% of red algae species occur in freshwater, environments with greater concentrations found in warmer areas. Except for two coastal cave dwelling species in the asexual class Cyanidiophyceae, there are no terrestrial species, which may be due to an evolutionary bottleneck in which the last common ancestor lost about 25% of its core genes and much of its evolutionary plasticity. The red algae form a distinct group characterized by having eukaryotic cells without flagella and centrioles, chloroplasts that lack external endoplasmic reticulum and contain unstacked (stroma) thylakoids, and use phycobiliproteins as accessory pigments, which give them their red color. Red algae store sugars as floridean starch, which is a type of starch that consists of highly branched amylopectin without amylose, as food reserves outside their plastids. Most red algae are also multicellular, macroscopic, marine, and reproduce sexually. The red algal life history is typically an alternation of generations that may have three generations rather than two. The coralline algae, which secrete calcium carbonate and play a major role in building coral reefs, belong here. Red algae such as dulse (Palmaria palmata) and laver (nori/gim) are a traditional part of European and Asian cuisines and are used to make other products such as agar, carrageenans and other food additives.
  • 11.3K
  • 11 Nov 2022
Topic Review
Master–Slave Dialectic
The master–slave dialectic is the common name for a famous passage of Georg Wilhelm Friedrich Hegel's Phenomenology of Spirit, though the original German phrase, Herrschaft und Knechtschaft, is more properly translated as Lordship and Bondage. It is widely considered a key element in Hegel's philosophical system, and has heavily influenced many subsequent philosophers. The passage describes, in narrative form, the development of self-consciousness as such in an encounter between what are thereby (i.e., emerging only from this encounter) two distinct, self-conscious beings. The essence of the dialectic is the movement or motion of recognizing, in which the two self-consciousnesses are constituted in being each recognized as self-conscious by the other. This movement, inexorably taken to its extreme, takes the form of a "struggle to the death" in which one masters the other, only to find that such lordship makes the very recognition he had sought impossible, since the bondsman, in this state, is not free to offer it.
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  • 08 Nov 2022
Topic Review
Power (International Relations)
Power in international relations is defined in several different ways. Modern discourse generally speaks in terms of state power, indicating both economic and military power. Those states that have significant amounts of power within the international system are referred to as small powers, middle powers, regional powers, great powers, superpowers, or hegemons, although there is no commonly accepted standard for what defines a powerful state. NATO Quint, the G7, the BRICS nations and the G20 are seen by academics as forms of governments that exercise varying degrees of influence within the international system. Entities other than states can also be relevant in power acquisition in international relations. Such entities can include multilateral international organizations, military alliance organizations like NATO, multinational corporations like Wal-Mart, non-governmental organizations such as the Roman Catholic Church, or other institutions such as the Hanseatic League and technology companies like Facebook and Google.
  • 11.3K
  • 11 Oct 2022
Topic Review
Golan Heights
The Golan Heights (Arabic: هَضْبَةُ الْجَوْلَانِ or Arabic: مُرْتَفَعَاتُ الْجَوْلَانِ, Hebrew: רמת הגולן‎, romanized: Ramat HaGolan), or simply the Golan, is a region in the Levant spanning about 1,800 square kilometres (690 sq mi). The region defined as the Golan Heights differs between disciplines: as a geological and biogeographical region, the term refers to a basaltic plateau bordered by the Yarmouk River in the south, the Sea of Galilee and Hula Valley in the west, the Anti-Lebanon with Mount Hermon in the north and Wadi Raqqad in the east. As a geopolitical region, it refers to the border region captured from Syria by Israel during the Six-Day War of 1967; the territory has been occupied by the latter since then and was subject to a de facto Israeli annexation in 1981. This region includes the western two-thirds of the geological Golan Heights and the Israeli-occupied part of Mount Hermon. The earliest evidence of human habitation on the Golan dates to the Upper Paleolithic period. According to the Bible, an Amorite kingdom in Bashan was conquered by the Israelites during the reign of King Og. Throughout the Biblical period, the Golan was "the focus of a power struggle between the kings of Israel and the Aramaeans who were based near modern-day Damascus." After Assyrian and Babylonian rule, the region came under the domination of Persia, following which Jews were freed from Babylonian captivity and allowed to return and resettle in the land. The Itureans, an Arab or Aramaic people, settled in the area in the 2nd century BCE. In the 16th century, the Golan was conquered by the Ottoman Empire. Within Ottoman Syria, the Golan was part of the Syria Vilayet. The area later became part of the French Mandate in Syria and the State of Damascus. When the mandate terminated in 1946, it became part of the newly independent Syrian Arab Republic. By the late-19th century, the Golan Heights was inhabited mostly by colonized peasants (fellaḥîn), Bedouin Arabs, Druze, Turkmen, and Circassians. Since the Six-Day War of 1967, the western two-thirds of the Golan Heights has been occupied and administered by Israel, whereas the eastern third remains under the control of Syria. Following the war, Syria dismissed any negotiations with Israel as part of the Khartoum Resolution at the 1967 Arab League summit. Construction of Israeli settlements began in the remainder of the territory held by Israel, which was under a military administration until the Knesset passed the Golan Heights Law in 1981, which applied Israeli law to the territory; the move has been described as an annexation. The Golan Heights Law was condemned by the United Nations Security Council in Resolution 497, which stated that "the Israeli decision to impose its laws, jurisdiction, and administration in the occupied Syrian Golan Heights is null and void and without international legal effect", and Resolution 242, which emphasizes the "inadmissibility of the acquisition of territory by war". Israel maintains it has a right to retain the Golan, also citing the text of Resolution 242, which calls for "secure and recognized boundaries free from threats or acts of force". After the onset of the Syrian Civil War in 2011, control of the Syrian-administered part of the Golan Heights was split between the state government and Syrian opposition forces, with the United Nations Disengagement Observer Force (UNDOF) maintaining a 266 km2 (103 sq mi) buffer zone in between to help implement the Israeli–Syrian ceasefire across the Purple Line. From 2012 to 2018, the eastern half of the Golan Heights became a scene of repeated battles between the Syrian Army, rebel factions of the Syrian opposition (including the United States -backed Southern Front) as well as various jihadist organizations such as al-Nusra Front and the Islamic State of Iraq and the Levant-affiliated Khalid ibn al-Walid Army. In July 2018, the Syrian government regained full control over the eastern Golan Heights. On 25 March 2019, then-President of the United States Donald Trump proclaimed US recognition of the Golan Heights as a part of the State of Israel, making it the first country to do so. The 28 member states of the European Union declared in turn that they do not recognize Israeli sovereignty, and several experts on international law reiterated that the principle remains that land gained by either defensive or offensive wars cannot be legally annexed under international law.
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  • 18 Nov 2022
Topic Review
Straight-Three Engine
A straight-three engine, also known as an inline-triple, or inline-three (abbreviated I3 or L3), is a reciprocating piston internal combustion engine with three cylinders arranged in a straight line or plane, side by side.
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  • 31 Oct 2022
Topic Review
Broadcast Programming
Television scheduling strategies are employed to give programs the best possible chance of attracting and retaining an audience. They are used to deliver programs to audiences when they are most likely to want to watch them and deliver audiences to advertisers in the composition that makes their advertising most likely to be effective. Digitally based broadcast programming mechanisms are known as electronic program guides (EPG). At a micro level, scheduling is the minute planning of the transmission; what to broadcast and when, ensuring an adequate or maximum utilization of airtime.
  • 11.2K
  • 28 Nov 2022
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