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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
Shear Strain
In physics, deformation is the continuum mechanics transformation of a body from a reference configuration to a current configuration. A configuration is a set containing the positions of all particles of the body. A deformation can occur because of external loads, intrinsic activity (e.g. muscle contraction), body forces (such as gravity or electromagnetic forces), or changes in temperature, moisture content, or chemical reactions, etc. Strain is related to deformation in terms of relative displacement of particles in the body that excludes rigid-body motions. Different equivalent choices may be made for the expression of a strain field depending on whether it is defined with respect to the initial or the final configuration of the body and on whether the metric tensor or its dual is considered. In a continuous body, a deformation field results from a stress field due to applied forces or because of some changes in the temperature field of the body. The relation between stress and strain is expressed by constitutive equations, e.g., Hooke's law for linear elastic materials. Deformations which cease to exist after the stress field is removed are termed as elastic deformation. In this case, the continuum completely recovers its original configuration. On the other hand, irreversible deformations remain. They exist even after stresses have been removed. One type of irreversible deformation is plastic deformation, which occurs in material bodies after stresses have attained a certain threshold value known as the elastic limit or yield stress, and are the result of slip, or dislocation mechanisms at the atomic level. Another type of irreversible deformation is viscous deformation, which is the irreversible part of viscoelastic deformation. In the case of elastic deformations, the response function linking strain to the deforming stress is the compliance tensor of the material.
  • 5.1K
  • 11 Nov 2022
Topic Review
Desert Island
A deserted island or uninhabited island is an island that is not permanently populated by humans. Uninhabited islands are often used in movies or stories about shipwrecked people, and are also used as stereotypes for the idea of "paradise". Some uninhabited islands are protected as nature reserves and some are privately owned. Devon Island in Canada is claimed to be the largest uninhabited island in the world. Small coral atolls or islands usually have no source of fresh water, but at times a fresh water lens (Ghyben–Herzberg lens) can be reached with a well.
  • 5.1K
  • 14 Oct 2022
Topic Review
Spent Oil Bleaching Earths
Spent oil bleaching earth (SOBE) is a waste product obtained in the refining process of oil. It is estimated that 120 million tons of oil are processed with bleaching earth worldwide, generating 2.5 million tons of spent bleaching earth as residue. Moreover, the serious fire and contamination risks that arise during storage and disposal of spent bleaching earth require appropriate technical solutions. The current treatment of SOBE residue is not in line with the new circular economy policies promoted by the European Union, since in most cases it is disposed of in landfills. New technologies that allow oil recovery and treatment of the earths, aiming to convert them into useful products are then needed. 
  • 5.1K
  • 26 Jul 2021
Topic Review
Rural Tourism Destination
Rural tourism is considered a high potential form of tourism, enhanced by the demand for more sustainable and nature-based solutions, and able to contribute to territory resilience. A rural area is not necessarily a tourist destination, but it might become one, if agricultural enterprises are willing to diversify their economic activities by investing in rural tourism, and local actors provide active support and co-participation.
  • 5.1K
  • 05 Jan 2022
Topic Review
Sheep Meat Processed Products
A concise review of the origin and type of the most important sheep and goat processed meat products produced in different countries and world regions is made. The manuscript also summarizes the most recent studies on sheep and goat processed meats on the physicochemical characterizations, sensory quality, microbiological quality and safety. Some conclusions and future trends in production, processing and commercial potentiality for sheep and goat processed meat products are discussed.
  • 5.1K
  • 06 Dec 2023
Topic Review
Hole-Transporting Layer in Perovskite Solar Cells
Organic-inorganic halide perovskite solar cells (PSCs) have received particular attention because of the high-power conversion efficiencies (PCEs), facile fabrication route and low cost. The hole-transporting layer (HTL) play an important role in PSCs to effectively extract holes from the perovskite film and to transport holes to the metal electrode in normal PSCs. 
  • 5.1K
  • 09 Aug 2022
Topic Review
South Korea's Green New Deal
Originally proposed as a post-COVID-19 stimulus plan, the Green New Deal is a sustainability-centered strategy for building a low-carbon and climate-neutral economy. The Green New Deal sets out eight targets to be accomplished under three strategic areas: green urban development, low-carbon decentralized energy, and innovative green industry. The Deal also takes measures to protect the people and sectors at a higher risk of being left behind in the process of the economic transition. It is an upgraded version of the “Green Growth” national policy, with more emphasis on sustainability in addition to the growth aspect.
  • 5.1K
  • 17 Dec 2020
Topic Review
Ural–Altaic Languages
Ural–Altaic, Uralo-Altaic or Uraltaic is a linguistic convergence zone and former language-family proposal uniting the Uralic and the Altaic (in the narrow sense) languages. It is generally now agreed that even the Altaic languages most likely do not share a common descent: the similarities among Turkic, Mongolic and Tungusic are better explained by diffusion and borrowing. The term continues to be used for the central Eurasian typological, grammatical and lexical convergence zone. Indeed, "Ural-Altaic" may be preferable to "Altaic" in this sense. For example, J. Janhunen states that "speaking of 'Altaic' instead of 'Ural-Altaic' is a misconception, for there are no areal or typological features that are specific to 'Altaic' without Uralic." Originally suggested in the 18th century, the genealogical and racial hypotheses remained debated into the mid-20th century, often with disagreements exacerbated by pan-nationalist agendas. It had many proponents in Britain. Since the 1960s, the proposed language family has been widely rejected. A relationship between the Altaic, Indo-European and Uralic families was revived in the context of the Nostratic hypothesis, which was popular for a time, with for example Allan Bomhard treating Uralic, Altaic and Indo-European as coordinate branches. However, Nostratic too is now mostly rejected.
  • 5.1K
  • 31 Oct 2022
Topic Review
BM-30 Smerch
The BM-30 Smerch (Russian: Смерч, "tornado", "whirlwind"), 9K58 Smerch or 9A52-2 Smerch-M is a Soviet heavy multiple rocket launcher. The system is intended to defeat personnel, armored, and soft targets in concentration areas, artillery batteries, command posts and ammunition depots. It was designed in the early 1980s and entered service in the Soviet Army in 1989. When first observed by the West in 1983, it received the code MRL 280mm M1983. It is expected to be superseded by the 9A52-4 Tornado.
  • 5.1K
  • 15 Nov 2022
Topic Review
Emergence of Society 5.0
The Society 5.0 emerged as an Japanese government program in which the government wish to establish a better, super-smart and more prosperous human-centered society, with the support of the technological innovations. The goal  of the program is also to recover the Japanese economy. The similar program is  known in Europe as  Industry 4.0. or Fourth Industrial revolution and in USA as Industrial Internet.
  • 5.1K
  • 17 Oct 2020
Topic Review
Aquaculture Food Production in Portugal
World aquaculture food production rises every year, amounting, by 2018, to another all-time record of 82.1 million tonnes of farmed seafood, with Asia leading global production. In Europe, although coastal countries present historical fishing habits, aquaculture is in true expansion. Norway, the leading European producer, is the eighth main producer worldwide. Portugal is a traditional fishing country but has invested in the development of aquaculture for the past decade, attaining, by 2018, 13.3 tonnes produced, making Portugal the 16th main producer amongst European Union member states that year. Most Portuguese aquaculture facilities operate in coastal systems, resorting to extensive and semi-intensive rearing techniques. In Portugal, marine food production in transitional systems is particularly interesting as the practice has, worldwide, been continuously substituted by intensive methods. In fact, facilities in transitional systems have developed over time and products gained higher commercial value.
  • 5.1K
  • 18 Mar 2022
Topic Review
Natural Phenols
Phenols are widespread in nature, being the major components of several plants and essential oils. Natural phenols’ anti-microbial, anti-bacterial, anti-oxidant, pharmacological and nutritional properties are, nowadays, well established. Hence, given their peculiar biological role, numerous studies are currently ongoing to overcome their limitations, as well as to enhance their activity.
  • 5.1K
  • 29 Sep 2021
Topic Review
Chi-Square Distribution
In probability theory and statistics, the chi-square distribution (also chi-squared or χ2-distribution) with k degrees of freedom is the distribution of a sum of the squares of k independent standard normal random variables. The chi-square distribution is a special case of the gamma distribution and is one of the most widely used probability distributions in inferential statistics, notably in hypothesis testing and in construction of confidence intervals. This distribution is sometimes called the central chi-square distribution, a special case of the more general noncentral chi-square distribution. The chi-square distribution is used in the common chi-square tests for goodness of fit of an observed distribution to a theoretical one, the independence of two criteria of classification of qualitative data, and in confidence interval estimation for a population standard deviation of a normal distribution from a sample standard deviation. Many other statistical tests also use this distribution, such as Friedman's analysis of variance by ranks.
  • 5.1K
  • 11 Nov 2022
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.
  • 5.1K
  • 17 Feb 2023
Topic Review
Energy Technology
Energy technology is an interdisciplinary engineering science having to do with the efficient, safe, environmentally friendly, and economical extraction, conversion, transportation, storage, and use of energy, targeted towards yielding high efficiency whilst skirting side effects on humans, nature, and the environment. For people, energy is an overwhelming need, and as a scarce resource, it has been an underlying cause of political conflicts and wars. The gathering and use of energy resources can be harmful to local ecosystems and may have global outcomes. Energy is also the capacity to do work. We can get energy from food. Energy can be of different forms such as kinetic, potential, mechanical, heat, light etc. Energy is required for individuals and the whole society for lighting, heating, cooking, running, industries, operating transportation and so forth. Basically there are two types of energy depending on the source s they are; 1.Renewable Energy Sources 2.Non-Renewable Energy Sources
  • 5.1K
  • 11 Nov 2022
Topic Review
Malayan Languages
The Malay or Malayan languages are a group of closely related languages spoken by Malays and related peoples across Brunei, Indonesia, Malaysia, Singapore, Southern Thailand and the far southern parts of the Philippines. They have traditionally been classified as Malay, Para-Malay, and Aboriginal Malay, but this reflects geography and ethnicity rather than a proper linguistic classification. The Malayan languages are mutually intelligible to varying extents, though the distinction between language and dialect is unclear in many cases. Para-Malay includes the Malayan languages of Sumatra. They are: Minangkabau, Central Malay (Bengkulu), Pekal, Musi (Palembang), Negeri Sembilan (Malaysia), and Duano’. Aboriginal Malay are the Malayan languages spoken by the Orang Asli (Proto-Malay) in Malaya. They are Jakun, Orang Kanaq, Orang Seletar, and Temuan. The other Malayan languages, included in neither of these groups, are associated with the expansion of the Malays across the archipelago. They include Malaccan Malay (Malaysian and Indonesian), Kedah Malay, Kedayan/Brunei Malay, Berau Malay, Bangka Malay, Jambi Malay, Kutai Malay, Loncong, Pattani Malay, and Banjarese. There are also several Malay-based creole languages, such as Betawi, Cocos Malay, Manado Malay and Sabah Malay, which may be more or less distinct from standard (Malaccan) Malay.
  • 5.1K
  • 13 Oct 2022
Topic Review Peer Reviewed
Helen Nemanjić (1250–1314)
Queen Helen Nemanjić (?–Brnjaci near Zubin Potok, February 8, 1314) was a Serbian medieval queen and consort of King Stefan Uroš I (r. 1243–1276), the fifth ruler of the Serbian Nemanide dynasty. She was the mother of the kings Stefan Dragutin and Stefan Uroš II Milutin. Today, she is known as Helen of Anjou (Jelena Anžujska in Serbian) although her real name was most probably Heleni Angelina (Ελένη Aγγελίνα). She was the founder of the Serbian Orthodox monastery of Gradac as well as four Franciscan abbeys in Kotor, Bar, Ulcinj, and Shkodër. Together with her sons, Kings Stefan Dragutin and Stefan Uroš II Milutin she helpedrenovation of Benedictine abbey of Sts. Sergius and Bacchus near Shkodër on Boyana river in present-day Albania. After the death of her husband, she ruled Zeta and Travunija until 1306. She was known for her religious tolerance and charitable and educational endeavors. She was elevated to sainthood by the Serbian Orthodox Church. Along with Empress Helen, the wife of Serbian Emperor Stefan Uroš IV Dušan, Queen Helen was the most frequently painted woman of Serbian medieval art. Six of her portraits can be found in the monumental painting ensembles of the Serbian medieval monasteries of Sopoćani, Gradac, Arilje, Đurđevi Stupovi (Pillars of St. George), and Gračanica, as well as on two icons and one seal. Queen Helen is also the only female Serbian medieval ruler whose vita was included in the famous collection of the “Lives of Serbian Kings and Archbishops” by Archbishop Danilo II, a prominent church leader, warrior, and writer. 
  • 5.1K
  • 13 Apr 2022
Topic Review
Effects of Creatine Supplementation on Brain Function
Creatine, a nitrogenous organic compound derived from reactions involving the amino acids arginine, glycine, and methionine, is important for resynthesizing ATP, particularly during times of increased metabolic demand (e.g., sleep deprivation, mental health conditions, or neurological diseases). Creatine supplementation (and guanidinoacetic acid; GAA) has the ability to increase brain creatine content in humans. Furthermore, creatine has shown some promise for attenuating symptoms of concussion, mild traumatic brain injury and depression but its effect on neurodegenerative diseases appears to be lacking. 
  • 5.1K
  • 09 Jun 2022
Topic Review
Potentially Toxic Elements
Potentially toxic element (PTE) pollution is a major abiotic stress, which reduces plant growth and affects food quality by entering the food chain, and ultimately poses hazards to human health.
  • 5.1K
  • 18 May 2021
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