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Topic Review
Starch Modification
Currently, new methods for producing starch citrates with improved functional and rheological properties while maintaining the highest possible content of resistant starch are being sought. The entry presents an overview of recent studies on the production, properties. And applicability of starch citrates with special attention paid to their role as preparations of resistant starch (RS). The use of citric acid for modification of starch is better for the technology process, while using cross-linking is better than simply using esterification.It may be concluded that the work on starch citrate esters represent a topical and meaningful direction of investigations on modified starch preparations. The possibility of modifying starch preparations by esterification/cross-linking with citric acid allows for the production of modified starch, which can be used in the pharmaceutical, packaging, or food industries. Especially significant may be investigations of resistant starch produced via esterification with citric acid because this method produces preparations exhibiting significant resistance and, simultaneously, good functional properties, which are potentially applicable as health-promoting additives that increase the dietary fiber content of food products.
  • 5.1K
  • 27 Oct 2020
Topic Review
Extracellular Matrix and Its Artificial Substitutes
The existence of orderly structures such as tissues and organs is made possible by cell adhesion, i.e. the process by which cells attach to neighbouring cells and a supporting substance in the form of the extracellular matrix. The extracellular matrix is a three-dimensional structure composed of collagens, elastin and various proteoglycans and glycoproteins. It is a storehouse for multiple signalling factors. Tissue disruption often prevents the natural reconstitution of the matrix. The use of appropriate implants is then required. The possibilities of regenerating damaged tissues using an artificial matrix substitute are described, detailing the host response to the implant. An important issue is the surface properties of such an implant and the possibilities of their modification.
  • 5.1K
  • 25 Mar 2022
Topic Review
Space Travel Using Constant Acceleration
Constant acceleration is a proposed aspect of most future forms of space travel. It entails that the propulsion system of whatever kind operate continuously with a steady acceleration, rather than the brief impulsive thrusts used by chemical rockets — for the first half of the journey it constantly pushes the spacecraft towards its destination, and for the last half of the journey it constantly uses backthrust, so that the spaceship arrives at the destination at a standstill.
  • 5.1K
  • 11 Oct 2022
Topic Review
Mammy Archetype
A mammy, also spelled mammie, is a U.S. stereotype, especially in the South, for a black woman who worked in a white family and nursed the family's children.
  • 5.0K
  • 29 Nov 2022
Biography
William Luther Pierce
William Luther Pierce III (September 11, 1933 – July 23, 2002) was an American white supremacist, author, and political activist.[1][2] He was one of the most influential ideologues of the white nationalist movement for some 30 years before his death. A physicist by profession, he was also an author under the pseudonym Andrew Macdonald of the novels The Turner Diaries and Hunter. Pierce founde
  • 5.0K
  • 25 Nov 2022
Topic Review
Evolutionary History of Life
The evolutionary history of life on Earth traces the processes by which living and fossil organisms evolved, from the earliest emergence of life to the present. Earth formed about 4.5 billion years (Ga) ago and evidence suggests life emerged prior to 3.7 Ga. (Although there is some evidence of life as early as 4.1 to 4.28 Ga, it remains controversial due to the possible non-biological formation of the purported fossils.) The similarities among all known present-day species indicate that they have diverged through the process of evolution from a common ancestor. Approximately 1 trillion species currently live on Earth of which only 1.75–1.8 million have been named and 1.6 million documented in a central database. These currently living species represent less than one percent of all species that have ever lived on earth. The earliest evidence of life comes from biogenic carbon signatures and stromatolite fossils discovered in 3.7 billion-year-old metasedimentary rocks from western Greenland. In 2015, possible "remains of biotic life" were found in 4.1 billion-year-old rocks in Western Australia. In March 2017, putative evidence of possibly the oldest forms of life on Earth was reported in the form of fossilized microorganisms discovered in hydrothermal vent precipitates in the Nuvvuagittuq Belt of Quebec, Canada, that may have lived as early as 4.28 billion years ago, not long after the oceans formed 4.4 billion years ago, and not long after the formation of the Earth 4.54 billion years ago. Microbial mats of coexisting bacteria and archaea were the dominant form of life in the early Archean Epoch and many of the major steps in early evolution are thought to have taken place in this environment. The evolution of photosynthesis, around 3.5 Ga, eventually led to a buildup of its waste product, oxygen, in the atmosphere, leading to the great oxygenation event, beginning around 2.4 Ga. The earliest evidence of eukaryotes (complex cells with organelles) dates from 1.85 Ga, and while they may have been present earlier, their diversification accelerated when they started using oxygen in their metabolism. Later, around 1.7 Ga, multicellular organisms began to appear, with differentiated cells performing specialised functions. Sexual reproduction, which involves the fusion of male and female reproductive cells (gametes) to create a zygote in a process called fertilization is, in contrast to asexual reproduction, the primary method of reproduction for the vast majority of macroscopic organisms, including almost all eukaryotes (which includes animals and plants). However the origin and evolution of sexual reproduction remain a puzzle for biologists though it did evolve from a common ancestor that was a single celled eukaryotic species. Bilateria, animals having a left and a right side that are mirror images of each other, appeared by 555 Ma (million years ago). The earliest complex land plants date back to around 850 Ma, from carbon isotopes in Precambrian rocks, while algae-like multicellular land plants are dated back even to about 1 billion years ago, although evidence suggests that microorganisms formed the earliest terrestrial ecosystems, at least 2.7 Ga. Microorganisms are thought to have paved the way for the inception of land plants in the Ordovician. Land plants were so successful that they are thought to have contributed to the Late Devonian extinction event. (The long causal chain implied seems to involve the success of early tree archaeopteris (1) drew down CO2 levels, leading to global cooling and lowered sea levels, (2) roots of archeopteris fostered soil development which increased rock weathering, and the subsequent nutrient run-off may have triggered algal blooms resulting in anoxic events which caused marine-life die-offs. Marine species were the primary victims of the Late Devonian extinction.) Ediacara biota appear during the Ediacaran period, while vertebrates, along with most other modern phyla originated about 525 Ma during the Cambrian explosion. During the Permian period, synapsids, including the ancestors of mammals, dominated the land, but most of this group became extinct in the Permian–Triassic extinction event 252 Ma. During the recovery from this catastrophe, archosaurs became the most abundant land vertebrates; one archosaur group, the dinosaurs, dominated the Jurassic and Cretaceous periods. After the Cretaceous–Paleogene extinction event 66 Ma killed off the non-avian dinosaurs, mammals increased rapidly in size and diversity. Such mass extinctions may have accelerated evolution by providing opportunities for new groups of organisms to diversify.
  • 5.0K
  • 24 Nov 2022
Topic Review
Group Work
Group work is a form of voluntary association of members benefiting from cooperative learning, that enhances the total output of the activity than when done individually. It aims to cater for individual differences, develop skills (e.g. communication skills, collaborative skills, critical thinking skills), generic knowledge and socially acceptable attitudes or to generate conforming standards of behavior and judgement, a "group mind". Specifically in psychotherapy and social work, "group work" refers to group therapy, offered by a practitioner trained in psychotherapy, psychoanalysis, counseling or other relevant discipline. The field of Social work includes all voluntary attempts to extend benefits in response to a bio-psycho-social needs and avails them through scientific knowledge and structured methods. There are six approaches in Social Work:
  • 5.0K
  • 31 Oct 2022
Topic Review
List of Dell PowerEdge Servers
Dell PowerEdge is a server line by Dell, following the naming convention for other Dell products: the PowerVault (data storage) and the PowerConnect (data transfer & switches). Below is an overview of current and former servers within Dell's PowerEdge product line. Different models are or were available as towers, 19-inch racks or blades. In the current naming scheme, towers are designated by T, racks by R, and blades by M (for modular). The 19″ rack-servers come in different physical heights expressed in rack units or U. Most modern servers are either 1U or 2U high while in the past the 4U was more common.
  • 5.0K
  • 21 Oct 2022
Topic Review
Restoration Movement
The Restoration Movement (also known as the American Restoration Movement or the Stone-Campbell Movement, and pejoratively as Campbellism) is a Christian movement that began on the United States frontier during the Second Great Awakening (1790–1840) of the early 19th century. The pioneers of this movement were seeking to reform the church from within and sought "the unification of all Christians in a single body patterned after the church of the New Testament.":54 Especially since the mid-20th century, members of these churches do not identify as Protestant but simply as Christian.:213 The Restoration Movement developed from several independent strands of religious revival that idealized early Christianity. Two groups, which independently developed similar approaches to the Christian faith, were particularly important. The first, led by Barton W. Stone, began at Cane Ridge, Kentucky, and identified as "Christians". The second began in western Pennsylvania and Virginia (now West Virginia) and was led by Thomas Campbell and his son, Alexander Campbell, both educated in Scotland; they eventually used the name "Disciples of Christ". Both groups sought to restore the whole Christian church on the pattern set forth in the New Testament, and both believed that creeds kept Christianity divided. In 1832 they joined in fellowship with a handshake. Among other things, they were united in the belief that Jesus is the Christ, the Son of God; that Christians should celebrate the Lord's Supper on the first day of each week; and that baptism of adult believers by immersion in water is a necessary condition for salvation. Because the founders wanted to abandon all denominational labels, they used the biblical names for the followers of Jesus.:27 Both groups promoted a return to the purposes of the 1st-century churches as described in the New Testament. One historian of the movement has argued that it was primarily a unity movement, with the restoration motif playing a subordinate role.:8 The Restoration Movement has since divided into multiple separate groups. There are three main branches in the U.S.: the Churches of Christ, the unaffiliated Christian Church/Church of Christ congregations, and the Christian Church (Disciples of Christ). Some characterize the divisions in the movement as the result of the tension between the goals of restoration and ecumenism: the Churches of Christ and unaffiliated Christian Church/Church of Christ congregations resolved the tension by stressing restoration, while the Christian Church (Disciples of Christ) resolved the tension by stressing ecumenism.:383 A number of groups outside the U.S. also have historical associations with this movement, such as the Evangelical Christian Church in Canada and the Churches of Christ in Australia. Because the Restoration Movement lacks any centralized structure, having originated in a variety of places with different leaders, there is no consistent nomenclature for the movement as a whole. The term "Restoration Movement" became popular during the 19th century; this appears to be due to the influence of Alexander Campbell's essays on "A Restoration of the Ancient Order of Things" in the Christian Baptist. The term "Stone-Campbell Movement" emerged towards the end of the 20th century as a way to avoid the difficulties associated with some of the other names that have been used, and to maintain a sense of the collective history of the movement.
  • 5.0K
  • 08 Dec 2022
Topic Review
Chemical looping
Chemical looping technology in general, is the rising star in chemical technologies, which is capable of low CO2 emissions with applications in the production of heat, fuels, chemicals, and electricity. This entry discusses the technology in general, gives an overview of some pilot scale plants and the different chemical looping processes with focus on the production of heat and chemicals, highlights the importance of the development of oxygen carrier materials with suitable properties, 2.11.0.0 2.11.0.0
  • 5.0K
  • 02 Nov 2020
Topic Review
Purple Non-Sulfur Bacteria
Photosynthetic bacteria (PSB) are procaryotes capable of carrying out photosynthesis by converting light energy into chemical energy. These photosynthetic bacteria can either grow in the presence or absence of oxygen (aerobic and anaerobic conditions) and can either use organic or inorganic substances as an electron donor to fix the atmospheric nitrogen (N2) and carbon dioxide (CO2). The purple non-sulfur bacteria belong to the anoxygenic group of PSB, and their major groups include Rhodopseudomonas spp. and Rhodobacter spp. They are naturally present in wastewater ponds, lagoons, lakes, sediments, wetland ecosystems, moist soils, hypersaline systems, and marine ecosystems. They possess versatile metabolic pathways and, therefore, are widely used in the livestock and fisheries industries , in bioremedial methods for heavy metals and sewage, and in biofuel production (electricity or photohydrogen). Studies have also shown that purple non-sulfur bacteria (PNSB) help boost soil fertility when applied directly to the soil, whereas PNSB applied to plants help improve crop growth and yield.
  • 5.0K
  • 14 Oct 2022
Topic Review
Synthetic Applications of Lawesson’s Reagent in Organic Synthesis
Lawesson’s reagent (LR) is a well-known classic example of a compound with unique construction and unusual chemical behavior, with a wide range of applications in synthetic organic chemistry. Its main functions were rounded for the thionation of various carbonyl groups in the early days. Now its use can help the chemistry community to understand innovative ideas. These include constructing biologically valuable heterocycles, coupling reactions, and the thionation of natural compounds.
  • 5.0K
  • 27 Nov 2021
Topic Review
Outline of Transhumanism
The following outline provides an overview of and a topical guide to transhumanism, an international intellectual and cultural movement that affirms the possibility and desirability of fundamentally transforming the human condition by developing and making widely available technologies to eliminate aging and to greatly enhance human intellectual, physical and psychological capacities. Transhumanist thinkers study the potential benefits and dangers of emerging and hypothetical technologies that could overcome fundamental human limitations as well as study the ethical matters involved in developing and using such technologies. They predict that human beings may eventually be able to transform themselves into beings with such greatly expanded abilities as to merit the label posthuman.
  • 5.0K
  • 04 Nov 2022
Topic Review
The Hero with a Thousand Faces
The Hero with a Thousand Faces (first published in 1949) is a work of comparative mythology by Joseph Campbell. In this book, Campbell discusses his theory of the mythological structure of the journey of the archetypal hero found in world myths. Since the publication of The Hero with a Thousand Faces, Campbell's theory has been consciously applied by a wide variety of modern writers and artists. Filmmaker George Lucas acknowledged Campbell's theory in mythology, and its influence on the Star Wars films. The Joseph Campbell Foundation and New World Library issued a new edition of The Hero with a Thousand Faces in July 2008 as part of the Collected Works of Joseph Campbell series of books, audio and video recordings. In 2011, Time (magazine) placed the book in its list of the 100 best and most influential books written in English since the magazine was founded in 1923.
  • 5.0K
  • 20 Oct 2022
Topic Review
Prokaryotic Translation
Prokaryotic translation is the process by which messenger RNA is translated into proteins in prokaryotes.
  • 5.0K
  • 19 Oct 2022
Topic Review
Electric Vehicles Charging/Discharging and Battery Degradation
The high penetration of electric vehicles (EVs) will burden the existing power delivery infrastructure if their charging and discharging are not adequately coordinated. The degradation of lithium-ion batteries occurs throughout their lives due to several chemicals and mechanical processes that reduce the cyclable lithium and other active materials. Battery degradation depends on many factors, such as the charging and discharging rates, depth of discharge (DOD), temperature, voltage, cycle number, and storage stage of charge.
  • 5.0K
  • 17 Jan 2023
Topic Review
Green Extraction Techniques for Active Ingredients in Tea
The so-called “Green Extraction”—which is based on the design of different extraction processes for the reduction in energy consumption, as well as the usage of alternative solvents and renewable natural materials —was developed.
  • 5.0K
  • 17 Feb 2023
Topic Review
Primal Therapy
Primal therapy is a trauma-based psychotherapy created by Arthur Janov, who argues that neurosis is caused by the repressed pain of childhood trauma. Janov argues that repressed pain can be sequentially brought to conscious awareness and resolved through re-experiencing specific incidents and fully expressing the resulting pain during therapy. In therapy, the patient recalls and reenacts a particularly disturbing past experience usually occurring early in life and expresses normally repressed anger or frustration especially through spontaneous and unrestrained screams, hysteria, or violence. Primal therapy was developed as a means of eliciting the repressed pain; the term Pain is capitalized in discussions of primal therapy when referring to any repressed emotional distress and its purported long-lasting psychological effects. Janov criticizes the talking therapies as they deal primarily with the cerebral cortex and higher-reasoning areas and do not access the source of Pain within the more basic parts of the central nervous system. Primal therapy is used to re-experience childhood pain—i.e., felt rather than conceptual memories—in an attempt to resolve the pain through complete processing and integration, becoming real. An intended objective of the therapy is to lessen or eliminate the hold early trauma exerts on adult behaviour. Primal therapy became very influential during a brief period in the early 1970s, after the publication of Janov's first book, The Primal Scream. It inspired hundreds of spin-off clinics worldwide and served as an inspiration for many popular cultural icons. Singer-songwriter John Lennon, actor James Earl Jones, and pianist Roger Williams were prominent advocates of primal therapy. Primal therapy has since declined in popularity, partly because Janov had not demonstrated in research the outcomes necessary to convince research-oriented psychotherapists of its effectiveness. Proponents of the methodology continue to advocate and practice the therapy or variations of it.
  • 5.0K
  • 23 Nov 2022
Topic Review
Bessel Beam
Diffraction is a phenomenon related to the wave nature of light and arises when a propagating wave comes across an obstacle. Consequently, the wave can be transformed in amplitude or phase and diffraction occurs. Those parts of the wavefront avoiding an obstacle form a diffraction pattern after interfering with each other. In this review paper, we have discussed the topic of non-diffractive beams, explicitly Bessel beams. Such beams provide some resistance to diffraction and hence are hypothetically a phenomenal alternate to Gaussian beams in several circumstances. Several outstanding applications are coined to Bessel beams and have been employed in commercial applications. We have discussed several hot applications based on these magnificent beams such as optical trapping, material processing, free-space long-distance self-healing beams, optical coherence tomography, superresolution, sharp focusing, polarization transformation, increased depth of focus, birefringence detection based on astigmatic transformed BB and encryption in optical communication. According to our knowledge, each topic presented in this entry is justifiably explained.
  • 5.0K
  • 09 Dec 2020
Topic Review
Outsourcing in Supply Chain Management
Outsourcing is one of the major challenges for production firms in the current supply chain management (SCM) due to limited skilled workers and technology resources. There are too many parameters involved in the strategic decisions of the outsourcing level, quantity, quality, and cost. 
  • 5.0K
  • 27 Apr 2022
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