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Topic Review
Lignosulfonates
Lignosulfonates are biobased surfactants and specialty chemicals, which are usually produced as a byproduct during sulfite pulping of wood. They are the technical lignin that is, by far, the most commercially traded and are hence vital for replacing non‑renewable and fossil‑based chemicals. Due to their prominent use as plasticizers, dispersants, and stabilizers, the physicochemical properties of lignosulfonates play a key role in determining their end‑use and performance. Their chemical composition and structure are inherently linked to the characteristic behavior of lignosulfonates. This entry hence outlines the fundamental chemistry of lignosulfonates, while discussing the following physicochemical properties: · Solubility in different solvents · Conformation and shape in aqueous solution · Self-association and agglomeration in aqueous solution · Precipitation · Adsorption at surfaces and interfaces
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  • 05 Jan 2021
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".
  • 11.3K
  • 21 Nov 2022
Topic Review
Kingdom
In biology, a kingdom (Latin: regnum, plural regna) is the second highest taxonomic rank, just below domain. Kingdoms are divided into smaller groups called phyla. Traditionally, some textbooks from the United States and Canada used a system of six kingdoms (Animalia, Plantae, Fungi, Protista, Archaea/Archaebacteria, and Bacteria/Eubacteria) while textbooks in Great Britain, India, Greece, Brazil and other countries use five kingdoms only (Animalia, Plantae, Fungi, Protista and Monera). Some recent classifications based on modern cladistics have explicitly abandoned the term kingdom, noting that some traditional kingdoms are not monophyletic, meaning that they do not consist of all the descendants of a common ancestor. The terms flora (for plants), fauna (for animals), and, in the 21st century, funga (for fungi) are also used for life present in a particular region or time.
  • 11.3K
  • 27 Nov 2022
Topic Review
List of ASTM International Standards (E)
This is a list of ASTM International standards for "Materials for Specific Applications".
  • 11.3K
  • 30 Sep 2022
Topic Review
Gemini Surfactants
Gemini surfactants are dimeric structures, composed of two hydrophobic chains and two hydrophilic heads, linked by a spacer at or near the head groups. They present lower CMC, better efficiency to form micelles, and solubilization capacity comparedto their conventional (monomeric) counterparts. They can also reduce the surface tension of water and the oil–water interfacial tension from 10 to 100 times. This behaviour depends mainly on the nature of their components (heads, hydrophobic chains and spacer); thus, their synthesis is focused mainly on varying the type and length of these components.
  • 11.3K
  • 21 Feb 2022
Topic Review
News International Phone Hacking Scandal
The News International phone hacking scandal was a controversy involving the now-defunct News of the World and other British newspapers owned by Rupert Murdoch. Employees of the newspaper were accused of engaging in phone hacking, police bribery, and exercising improper influence in the pursuit of stories. Whilst investigations conducted from 2005 to 2007 appeared to show that the paper's phone hacking activities were limited to celebrities, politicians, and members of the British royal family, in July 2011 it was revealed that the phones of murdered schoolgirl Milly Dowler, relatives of deceased British soldiers, and victims of the 7 July 2005 London bombings had also been hacked. The resulting public outcry against News Corporation and its owner Rupert Murdoch led to several high-profile resignations, including that of Murdoch as News Corporation director, Murdoch's son James as executive chairman, Dow Jones chief executive Les Hinton, News International legal manager Tom Crone, and chief executive Rebekah Brooks. The commissioner of London's Metropolitan Police Service (MPS), Sir Paul Stephenson, also resigned. Advertiser boycotts led to the closure of the News of the World on 10 July 2011, after 168 years of publication. Public pressure forced News Corporation to cancel its proposed takeover of the British satellite broadcaster BSkyB. The prime minister David Cameron announced on 6 July 2011 that a public inquiry, known as the Leveson Inquiry, would look into phone hacking and police bribery by the News of the World, consider the wider culture and ethics of the British newspaper industry and that the Press Complaints Commission would be replaced "entirely". A number of arrests and convictions followed, most notably of the former News of the World managing editor Andy Coulson. Murdoch and his son, James, were summoned to give evidence at the Leveson Inquiry. Over the course of his testimony, Rupert Murdoch admitted that a cover-up had taken place within the News of the World to hide the scope of the phone hacking. On 1 May 2012, a parliamentary select committee report concluded that Murdoch "exhibited wilful blindness to what was going on in his companies and publications" and stated that he was "not a fit person to exercise the stewardship of a major international company". On 3 July 2013, Channel 4 News broadcast a secret tape in which Murdoch dismissively claims that investigators were "totally incompetent" and acted over "next to nothing" and excuses his papers' actions as "part of the culture of Fleet Street".
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  • 11 Oct 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.
  • 11.2K
  • 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.
  • 11.2K
  • 13 Apr 2022
Topic Review
Timeline of Operating Systems
This article presents a timeline of events in the history of computer operating systems from 1951 to the current day. For a narrative explaining the overall developments, see the History of operating systems.
  • 11.2K
  • 04 Nov 2022
Topic Review
Geography of Middle-Earth
The geography of Middle-earth encompasses the physical, political, and moral geography of J. R. R. Tolkien's fictional world of Middle-earth, strictly a continent on the planet of Arda but widely taken to mean the physical world, and Eä, all of creation, as well as all of his writings about it. Arda was created as a flat world, incorporating a Western continent, Aman, which became the home of the godlike Valar, as well as Middle-earth. At the end of the First Age, the Western part of Middle-earth, Beleriand, was drowned in the War of Wrath. In the Second Age, a large island, Númenor, was created in the Great Sea, Belegaer, between Aman and Middle-earth; it was destroyed in a cataclysm at the end of the Second Age, in which Arda was remade as a spherical world, and Aman was removed so that Men could not reach it. In The Lord of the Rings, Middle-earth at the end of the Third Age is described as having free peoples, namely Men, Hobbits, Elves, and Dwarves in the West, opposed to peoples under the control of the Dark Lord Sauron in the East. Some commentators have seen this as implying a moral geography of Middle-earth.
  • 11.2K
  • 25 Oct 2022
Topic Review
Separatist Feminism
Separatist feminism is a form of radical feminism that holds that opposition to patriarchy is best done through focusing exclusively on women and girls. Some separatist feminists believe that men cannot make positive contributions to the feminist movement and that even well-intentioned men replicate the dynamics of patriarchy. Author Marilyn Frye describes separatist feminism as "separation of various sorts or modes from men and from institutions, relationships, roles and activities that are male-defined, male-dominated, and operating for the benefit of males and the maintenance of male privilege – this separation being initiated or maintained, at will, by women". In a tract on socialist feminism published in 1972, the Hyde Park Chapter of the Chicago Women's Liberation Union differentiated between separatism as an "ideological position" and as a "tactical position". In the same document, they further distinguished between separatism as "personal practice" and as "political position".
  • 11.2K
  • 27 Oct 2022
Topic Review
Vascular bundles
Vascular bundles play important roles in transporting nutrients, growth signals, amino acids, and proteins between aerial and underground tissues. 
  • 11.2K
  • 26 Feb 2021
Topic Review
Incircle and Excircles of a Triangle
In geometry, the incircle or inscribed circle of a triangle is the largest circle contained in the triangle; it touches (is tangent to) the three sides. The center of the incircle is a triangle center called the triangle's incenter. An excircle or escribed circle of the triangle is a circle lying outside the triangle, tangent to one of its sides and tangent to the extensions of the other two. Every triangle has three distinct excircles, each tangent to one of the triangle's sides. The center of the incircle, called the incenter, can be found as the intersection of the three internal angle bisectors. The center of an excircle is the intersection of the internal bisector of one angle (at vertex [math]\displaystyle{ A }[/math], for example) and the external bisectors of the other two. The center of this excircle is called the excenter relative to the vertex [math]\displaystyle{ A }[/math], or the excenter of [math]\displaystyle{ A }[/math]. Because the internal bisector of an angle is perpendicular to its external bisector, it follows that the center of the incircle together with the three excircle centers form an orthocentric system.:p. 182 All regular polygons have incircles tangent to all sides, but not all polygons do; those that do are tangential polygons. 
  • 11.2K
  • 11 Nov 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.
  • 11.2K
  • 29 Oct 2020
Topic Review
The Process of Wound Healing
Wound healing is a recovering process of damaged tissues by replacing dysfunctional injured cellular structures. Wounds occur as a result of accidental or surgical trauma and from a variety of medical conditions. This wound often causes pain, inflammation, and loss of function, which affects a patient’s life and financial costs.
  • 11.2K
  • 06 Sep 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.
  • 11.2K
  • 29 Sep 2022
Topic Review
Evolution of Elephants
Elephants are the largest existing land animals. Three living species are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant. They are an informal grouping within the proboscidean family Elephantidae. Elephantidae is the only surviving family of proboscideans; extinct members include the mastodons. Elephantidae also contains several extinct groups, including the mammoths and straight-tusked elephants. African elephants have larger ears and concave backs, whereas Asian elephants have smaller ears, and convex or level backs. The distinctive features of all elephants include a long proboscis called a trunk, tusks, large ear flaps, massive legs, and tough but sensitive skin. The trunk is used for breathing, bringing food and water to the mouth, and grasping objects. Tusks, which are derived from the incisor teeth, serve both as weapons and as tools for moving objects and digging. The large ear flaps assist in maintaining a constant body temperature as well as in communication. The pillar-like legs carry their great weight. Elephants are scattered throughout sub-Saharan Africa, South Asia, and Southeast Asia and are found in different habitats, including savannahs, forests, deserts, and marshes. They are herbivorous, and they stay near water when it is accessible. They are considered to be keystone species, due to their impact on their environments. Elephants have a fission–fusion society, in which multiple family groups come together to socialise. Females (cows) tend to live in family groups, which can consist of one female with her calves or several related females with offspring. The groups, which do not include bulls, are usually led by the oldest cow, known as the matriarch. Males (bulls) leave their family groups when they reach puberty and may live alone or with other males. Adult bulls mostly interact with family groups when looking for a mate. They enter a state of increased testosterone and aggression known as musth, which helps them gain dominance over other males as well as reproductive success. Calves are the centre of attention in their family groups and rely on their mothers for as long as three years. Elephants can live up to 70 years in the wild. They communicate by touch, sight, smell, and sound; elephants use infrasound, and seismic communication over long distances. Elephant intelligence has been compared with that of primates and cetaceans. They appear to have self-awareness, and appear to show empathy for dying and dead family members. African bush elephants and Asian elephants are listed as endangered and African forest elephants as critically endangered by the International Union for Conservation of Nature (IUCN). One of the biggest threats to elephant populations is the ivory trade, as the animals are poached for their ivory tusks. Other threats to wild elephants include habitat destruction and conflicts with local people. Elephants are used as working animals in Asia. In the past, they were used in war; today, they are often controversially put on display in zoos, or exploited for entertainment in circuses. Elephants are highly recognisable and have been featured in art, folklore, religion, literature, and popular culture.
  • 11.1K
  • 28 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.
  • 11.1K
  • 11 Oct 2022
Topic Review
Nutraceuticals
Nutraceuticals are essential food constituents that provide nutritional benefits as well as medicinal effects. The benefits of these foods are due to the presence of active compounds such as carotenoids, collagen hydrolysate, and dietary fibers.
  • 11.1K
  • 18 May 2021
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.
  • 11.1K
  • 01 Nov 2020
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