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Topic Review
DNA Barcoding
DNA barcoding is a method of species identification using a short section of DNA from a specific gene or genes. The premise of DNA barcoding is that, by comparison with a reference library of such DNA sections (also called "sequences"), an individual sequence can be used to uniquely identify an organism to species, in the same way that a supermarket scanner uses the familiar black stripes of the UPC barcode to identify an item in its stock against its reference database. These "barcodes" are sometimes used in an effort to identify unknown species, parts of an organism, or simply to catalog as many taxa as possible, or to compare with traditional taxonomy in an effort to determine species boundaries. Different gene regions are used to identify the different organismal groups using barcoding. The most commonly used barcode region for animals and some protists is a portion of the cytochrome c oxidase I (COI or COX1) gene, found in mitochondrial DNA. Other genes suitable for DNA barcoding are the internal transcribed spacer (ITS) rRNA often used for fungi and RuBisCO used for plants. Microorganisms are detected using different gene regions. The 16S rRNA gene for example is widely used in identification of prokaryotes, whereas the 18S rRNA gene is mostly used for detecting microbial eukaryotes. These gene regions are chosen because they have less intraspecific (within species) variation than interspecific (between species) variation, which is known as the "Barcoding Gap". Some applications of DNA barcoding include: identifying plant leaves even when flowers or fruits are not available; identifying pollen collected on the bodies of pollinating animals; identifying insect larvae which may have fewer diagnostic characters than adults; or investigating the diet of an animal based on its stomach content, saliva or feces. When barcoding is used to identify organisms from a sample containing DNA from more than one organism, the term DNA metabarcoding is used, e.g. DNA metabarcoding of diatom communities in rivers and streams, which is used to assess water quality.
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  • 16 Nov 2022
Topic Review
CRISPR-Cas Genome Editing Components in C. elegans
CRISPR-Cas allows us to introduce desired genome editing, including mutations, epitopes, and deletions, with unprecedented efficiency. The development of CRISPR-Cas has progressed to such an extent that it is now applicable in various fields, with the help of model organisms. C. elegans is one of the pioneering animals in which numerous CRISPR-Cas strategies have been rapidly established. Ironically, the emergence of numerous methods makes the choice of the correct method difficult. Choosing an appropriate selection or screening approach is the first step in planning a genome modification.
  • 5.4K
  • 30 Dec 2022
Topic Review Peer Reviewed
Stefan Uroš II Milutin Nemanjić (1282–1321)
King Stefan Uroš II Milutin Nemanjić (1282—Donje Nerodimlje, October 29, 1321) was a Serbian medieval king, the seventh ruler of the Serbian Nemanide dynasty, the son of King Stefan Uroš I (r. 1243–1276) and Queen Helen Nemanjić (see), the brother of the King Stefan Dragutin (r. 1276–1282) and the father of King Stefan Dečanski (r. 1322–1331). Together with his great grandfather Stefan Nemanja, the founder of the Nemanide dynasty, and his grandson, Emperor Stefan Uroš IV Dušan, King Milutin is considered the most powerful ruler of the Nemanide dynasty. The long and successful military breach of King Milutin, down the Vardar River Valley and deep into the Byzantine territories, represents the beginning of Serbian expansion into southeastern Europe, making it the dominant political power in the Balkan region in the 14th century. During that period, Serbian economic power grew rapidly, mostly because of the development of trading and mining. King Milutin founded Novo Brdo, an internationally important silver mining site. He started minting his own money, producing imitations of Venetian coins (grosso), which gradually diminished in value. This led to the ban of these coins by the Republic of Venice and provided King Milutin a place in Dante’s Divina Commedia. King Milutin had a specific philoktesia fervor: He built or renovated over three dozen Serbian Orthodox churches and monasteries not only in Serbia but also in Thessaloniki, Mt. Athos, Constantinople and The Holy Land. Over fifteen of his portraits can be found in the monumental painting ensembles of Serbian medieval monasteries as well as on two icons. 
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  • 13 Apr 2022
Topic Review
Covalent Adaptable Networks
Thermosets are known to be very reliable polymeric materials for high-performance and light-weight applications, due to their retained dimensional stability, chemical inertia and rigidity over a broad range of temperatures. However, once fully cured, they cannot be easily reshaped or reprocessed, thus leaving still unsolved the issues of recycling and the lack of technological flexibility. Vitrimers, introduced by Leibler et al. in 2011, are a valiant step in the direction of bridging the chasm between thermoplastics and thermosets. Owing to their dynamic covalent networks, they can retain mechanical stability and solvent resistance, but can also flow on demand upon heating. More generally, the family of Covalent Adaptable Networks (CANs) is gleaming with astounding potential, thanks to the huge variety of chemistries that may enable bond exchange. Arising from this signature feature, intriguing properties such as self-healing, recyclability and weldability may expand the horizons for thermosets in terms of improved life-span, sustainability and overall enhanced functionality and versatility. In this review, we present a comprehensive overview of the most promising studies featuring CANs and vitrimers specifically, with particular regard for their industrial applications. Investigations into composites and sustainable vitrimers from epoxy-based and elastomeric networks are covered in detail.
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  • 26 Oct 2020
Topic Review
Spiking Neural Networks
Spiking neural networks (SNNs) are artificial neural network models that more closely mimic natural neural networks. In addition to neuronal and synaptic state, SNNs also incorporate the concept of time into their operating model. The idea is that neurons in the SNN do not fire at each propagation cycle (as it happens with typical multi-layer perceptron networks), but rather fire only when a membrane potential – an intrinsic quality of the neuron related to its membrane electrical charge – reaches a specific value. When a neuron fires, it generates a signal which travels to other neurons which, in turn, increase or decrease their potentials in accordance with this signal (ref).
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  • 13 Oct 2021
Topic Review
Sulfur Mustard
Sulfur mustard, commonly known as mustard gas, is the prototypical substance of the sulfur-based family of cytotoxic and vesicant chemical warfare agents known as the sulfur mustards, which can form large blisters on exposed skin and in the lungs. They have a long history of use as a blister-agent in warfare and along with organoarsenic compounds are the most well-studied such agents. Related chemical compounds with similar chemical structure and similar properties form a class of compounds known collectively as sulfur mustards or mustard agents. Pure sulfur mustards are colorless, viscous liquids at room temperature. When used in impure form, such as warfare agents, they are usually yellow-brown and have an odor resembling mustard plants, garlic, or horseradish, hence the name. The common name of "mustard gas" is considered inaccurate because the sulfur mustard is not actually vaporized, but dispersed as a fine mist of liquid droplets. Sulfur mustard was originally assigned the name LOST, after the scientists Wilhelm Lommel and Wilhelm Steinkopf, who developed a method of large-scale production for the Imperial German Army in 1916. Mustard agents are regulated under the 1993 Chemical Weapons Convention. Three classes of chemicals are monitored under this Convention, with sulfur and nitrogen mustard grouped in Schedule 1, as substances with no use other than in chemical warfare. Mustard agents could be deployed by means of artillery shells, aerial bombs, rockets, or by spraying from warplanes or other aircraft. Sulfur mustard can be readily decontaminated through reaction with chloramine-T.
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  • 11 Nov 2022
Topic Review
ISO 29110
ISO/IEC 29110: Systems and Software Life Cycle Profiles and Guidelines for Very Small Entities (VSEs) International Standards (IS) and Technical Reports (TR) are targeted at Very Small Entities (VSEs). A Very Small Entity (VSE) is an enterprise, an organization, a department or a project having up to 25 people. The ISO/IEC 29110 is a series of international standards and guides entitled "Systems and Software Engineering — Lifecycle Profiles for Very Small Entities (VSEs)". The standards and technical reports were developed by working group 24 (WG24) of sub-committee 7 (SC7) of Joint Technical Committee 1 (JTC1) of the International Organization for Standardization and the International Electrotechnical Commission. Industries around the world have agreed that there are certain ways of working that produce predictable results. Companies that agree to use these agreed methods and then to have their compliance measured are called ISO certificated. Some ISO-certificated organizations require that their vendors also be ISO certificated. The general standard for software development, ISO/IEC/IEEE 12207, is appropriate for medium and large software development efforts. Similarly, the general standard for system development, ISO/IEC/IEEE 15288, is appropriate for medium and large system development efforts. Systems, in the context of ISO/IEC 29110, are typically composed of hardware and software components. Things work differently in small organisations; ISO 29110 reflects that.
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  • 07 Nov 2022
Topic Review
Plant-Based Antioxidants
Antioxidants are compounds that normally prevent lipid and protein oxidation. They play a major role in preventing many adverse conditions in the human body, including inflammation and cancer. Synthetic antioxidants are widely used in the food industry to prevent the production of adverse compounds that harm humans. However, plant and animal-based antioxidants are more appealing to consumers than synthetic antioxidants. Plant-based antioxidants are mainly phenolic compounds, carotenoids, and vitamins, while animal-based antioxidants are mainly whole protein or the peptides of meat, fish, egg, milk, and plant proteins. Plant-based antioxidants mainly consist of aromatic rings, while animal-based antioxidants mainly consist of amino acids. The phenolic compounds and peptides act differently in preventing oxidation and can use in the food and pharmaceutical industries. Therefore, compared with the animal-based antioxidants, plant-based compounds are more practical in the food industry. 
  • 5.4K
  • 07 Jun 2022
Topic Review
Information Deficit Model
In studies of the public understanding of science, the information deficit model (or simply deficit model) or science literacy/knowledge deficit model attributes public scepticism or hostility to science and technology to a lack of understanding, resulting from a lack of information. It is associated with a division between experts who have the information and non-experts who do not. The model implies that communication should focus on improving the transfer of information from experts to non-experts.
  • 5.4K
  • 17 Nov 2022
Topic Review
Newspeak
Newspeak is the language of Oceania, a fictional totalitarian state and the setting of the dystopian novel Nineteen Eighty-Four (1949), by George Orwell. To meet the ideological requirements of English Socialism (Ingsoc) in Oceania, the ruling Party created Newspeak, a controlled language of restricted grammar and limited vocabulary, meant to limit the freedom of thought—personal identity, self-expression, free will—that threatens the ideology of the régime of Big Brother and the Party, who have criminalized such concepts into thoughtcrime, as contradictions of Ingsoc orthodoxy. In "The Principles of Newspeak", the appendix to the novel, George Orwell explains that Newspeak usage follows most of the English grammar, yet is a language characterised by a continually diminishing vocabulary; complete thoughts reduced to simple terms of simplistic meaning. Linguistically, the contractions of Newspeak—Ingsoc (English Socialism), Minitrue (Ministry of Truth), etc.—derive from the syllabic abbreviations of Russian, which identify the government and social institutions of the Soviet Union, such as politburo (Politburo of the Central Committee of the Communist Party of the Soviet Union), Comintern (Communist International), kolkhoz (collective farm), and Komsomol (Young Communists' League). The long-term political purpose of the new language is for every member of the Party and society, except the Proles—the working-class of Oceania—to exclusively communicate in Newspeak, by A.D. 2050; during that 66-year transition, the usage of Oldspeak (Standard English) shall remain interspersed among Newspeak conversations. Newspeak is also a constructed language, of planned phonology, grammar, and vocabulary, like Basic English, which Orwell promoted (1942–44) during the Second World War (1939–45), and later rejected in the essay "Politics and the English Language" (1946), wherein he criticizes the bad usage of English in his day: dying metaphors, pretentious diction, and high-flown rhetoric, which produce the meaningless words of doublespeak, the product of unclear reasoning. Orwell's conclusion thematically reiterates linguistic decline: "I said earlier that the decadence of our language is probably curable. Those who deny this may argue that language merely reflects existing social conditions, and that we cannot influence its development, by any direct tinkering with words or constructions."
  • 5.4K
  • 08 Nov 2022
Topic Review
Mangrove Forest Functions and Services
Mangroves stand out as one of the most diverse and biologically significant natural systems in the world. Playing critical roles in maintaining the health and productivity of coastal ecosystems, mangroves provide a range of services and functions, including habitat for local fauna and flora, food and other goods, carbon sequestration, and protection from natural disasters such as storm surges and coastal erosion. 
  • 5.4K
  • 12 Sep 2023
Topic Review
Electrochemical Energy Storage/Conversion System
Electrochemical energy storage and conversion systems such as electrochemical capacitors, batteries and fuel cells are considered as the most important technologies proposing environmentally friendly and sustainable solutions to address rapidly growing global energy demands and environmental concerns. Their commercial applications individually or in combination of two or more devices are based on their distinguishing properties e.g., energy/power densities, cyclability and efficiencies.
  • 5.4K
  • 03 Dec 2020
Topic Review
Continuationism
Continuationism is a Christian theological belief that the gifts of the Holy Spirit have continued to the present age, specifically those sometimes called "sign gifts", such as tongues and prophecy. Continuationism is the opposite of cessationism. Continuationists believe that the miraculous gifts of the Holy Spirit are still distributed today, are still in use, and are still needed in the church. The same Holy Spirit that the Apostle Paul wrote of, claiming that it gave him supernatural abilities, was also written about in the Old Testament, which claims that it also endowed such abilities upon those whom God chose to accomplish his works, as in the New Testament. Historically, the Lutheran, Methodist, Moravian, and Pentecostal traditions of Christianity have espoused the doctrinal position of continuationism.
  • 5.4K
  • 11 Oct 2022
Topic Review
List of Aircraft (D)
This is a list of aircraft in alphabetical order beginning with 'D'.
  • 5.4K
  • 27 Oct 2022
Topic Review
Sustainability Green Industry 4.0
The Sustainability Green Industry (SGI) 4.0 framework captures the relations of Industry 4.0, green processes and sustainability in manufacturing. The framework is structured into three vertical levels: technological, process and development, integrated through the circular economy. The SGI 4.0 framework’s purpose is to explain how Industry 4.0 technologies create sustainability outcomes through green processes. The facilitating, enabling and supporting functions of green processes allow to understand how modern technologies can be linked to the concept of sustainability. In the literature we can find various concepts connecting Industry 4.0 and sustainability, however, the key role of green processes is not mentioned.
  • 5.4K
  • 25 Jun 2021
Topic Review
Sandwich Structures
Sandwich structures are a class of multifunctional high-performance structural composites that have the advantages of being lightweight, of a high strength-to-weight ratio, and of high specific energy absorption capabilities. 
  • 5.4K
  • 01 Dec 2022
Topic Review
Applications of Ant Colony Optimization
Ant-inspired metaheuristic algorithms known as ant colony optimization (ACO) offer an approach that has the ability to solve complex problems in both discrete and continuous domains. ACOs have gained significant attention in the field of water resources management, since many problems in this domain are non-linear, complex, challenging and also demand reliable solutions. 
  • 5.4K
  • 10 May 2023
Biography
Hans Adolf Krebs
Sir Hans Adolf Krebs (/krɛbz, krɛps/; 25 August 1900 – 22 November 1981)[1][2][3][4] was a German-born British biologist, physician and biochemist.[5] He was a pioneer scientist in the study of cellular respiration, a biochemical process in living cells that extracts energy from food and oxygen and makes it available to drive the processes of life.[6][7] He is best known for his discoveries
  • 5.4K
  • 29 Nov 2022
Topic Review
Paan
Paan (from Sanskrit: पर्ण, romanized: parṇá, lit. leaf, cognate with English fern) is a preparation combining betel leaf with areca nut widely consumed throughout South Asia and East Asia (mainly Taiwan). It is chewed for its stimulant effects. After chewing, it is either spat out or swallowed. Paan has many variations. Slaked lime (chuna) paste is commonly added to bind the leaves. Some preparations in the Indian subcontinent include katha paste or mukhwas to freshen the breath. Magahi paan is an expensive variety of betel which is grown in Aurangabad, Gaya and Nalanda districts of central Bihar. It is non-fibrous, sweeter, tastier and the softest of the lot. The origin and diffusion of betel chewing originates from and is closely tied to the Neolithic expansion of the Austronesian peoples. It was spread to the Indo-Pacific during prehistoric times, reaching Near Oceania at 3,400 to 3,000 BP; South India and Sri Lanka by 3,500 BP; Mainland Southeast Asia by 3,000 to 2,500 BP; Northern India by 1500 BP; and Madagascar by 600 BP. From India, it was also spread westwards to Persia and the Mediterranean. Paan (under a variety of names) is also consumed in many other Asian countries and elsewhere in the world by some Asian emigrants, with or without tobacco. It can be an addictive and stimulating formulation with adverse health effects, both with and without tobacco. The spit from chewing betel nuts, known as "buai pekpek" in Papua New Guinea, is often considered an eyesore. Because of this, many places have banned selling and chewing "buai".
  • 5.4K
  • 30 Sep 2022
Topic Review
The Brazilian Cement Sector
The worldwide cement industry plays an important role in addressing the climate change challenge. Brazil’s cement industry currently has 91 cement plants with an installed production capacity of 94 million tons per year and has started to calculate the net CO2 emissions to achieve a carbon-neutral cement sector by 2050. Accordingly, the carbon dioxide uptake due to mortar and concrete carbonation is subtracted from the carbon dioxide emitted by the chemical reaction for the calcination of lime, i.e., the calcination process performed during clinker production.
  • 5.4K
  • 07 Mar 2024
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