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Topic Review
Cellulose
Cellulose is the main substance of a plant’s cell walls, helping plants to remain stiff and upright, hence, it can be extracted from plant sources, agriculture waste, animals, and bacterial pellicle. It is composed of polymer chains consisting of unbranched β (1,4) linked D glucopyranosyl units (anhydroglucose unit, AGU).
  • 9.4K
  • 07 Feb 2021
Topic Review
Atomic Mass Unit
The dalton or unified atomic mass unit (SI symbols: Da or u) is a unit of mass widely used in physics and chemistry. . It is approximately the mass of one nucleon (either a proton or neutron). A mass of 1 Da is also referred to as the atomic mass constant and denoted by mu. Several definitions of this unit have been used, implying slightly different values. The current IUPAC endorsed definition is the unified atomic mass unit, denoted by the symbol u. As of 2019, the International System of Units (SI) lists the dalton, symbol Da, as a unit acceptable for use with the SI unit system and secondarily notes that the dalton (Da) and the unified atomic mass unit (u) are alternative names (and symbols) for the same unit. The symbol Da is more widely used in most fields. It is defined precisely as 1/12 of the mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state and at rest. Despite being an official abbreviation for a related obsolete unit and not widely used in the scientific literature, the abbreviation "amu" now often refers to the modern unit (Da or u) in many preparatory texts. As of June 2019, the value recommended by the Committee on Data for Science and Technology (CODATA) is 1.66053906660(50)×10−27 kg, or approximately 1.66 yoctograms. This unit is commonly used in physics and chemistry to express the mass of atomic-scale objects, such as atoms, molecules, and elementary particles. For example, an atom of helium has a mass of about 4 Da, and a molecule of acetylsalicylic acid (aspirin), C9H8O4, has a mass of about 180.16 Da. In general, the standard atomic weight of an element is the average weight of its atom as it occurs in nature, expressed in daltons. The molecular masses of proteins, nucleic acids, and other large polymers are often expressed with the units kilodalton (kDa), equal to 1000 daltons, megadalton (MDa), one million daltons, etc. Titin, one of the largest known proteins, has an atomic mass of between 3 and 3.7 megadaltons. The DNA of chromosome 1 in the human genome has about 249 million base pairs, each with an average mass of about 650 Da, or 156 GDa total. The mole is a unit of amount of substance, widely used in chemistry and physics, which was originally defined so that the mass of one mole of a substance, measured in grams, would be numerically equal to the average mass of one of its constituent particles, measured in daltons. That is, the molar mass of a chemical compound was meant to be numerically equal to its average molecular mass. For example, the average mass of one molecule of water is about 18.0153 daltons, and one mole of water is about 18.0153 grams. A protein whose molecule has an average mass of 64 kDa would have a molar mass of 64 kg/mol. However, while this equality can be assumed for almost all practical purposes, it is now only approximate, because of the way the mole was redefined on 20 May 2019. The mass in daltons of an atom is numerically very close to the number of nucleons A in its atomic nucleus. It follows that the molar mass of a compound (grams per mole) is also numerically close to the average number of nucleons per molecule. However, the mass of an atomic-scale object is affected by the binding energy of the nucleons in its atomic nuclei, as well as the mass and binding energy of the electrons. Therefore, this equality holds only for the carbon-12 atom in the stated conditions, and will vary for other substances. For example, the mass of one unbound atom of the common hydrogen isotope (hydrogen-1, protium) is 1.007825032241(94) Da, the mass of one free neutron is 1.008664915823(491) Da, and the mass of one hydrogen-2 (deuterium) atom is 2.014101778114(122) Da. In general, the difference (mass defect) is less than 0.1%; except for hydrogen (about 0.8%), helium-3 (0.5%), lithium (0.25%) and beryllium (0.15%). The atomic mass unit should not be confused with unit of mass in the atomic units systems, which is instead the electron rest mass (me).
  • 9.4K
  • 31 Oct 2022
Topic Review
Meaning and Determination of Electrode Surface Area
The interfacial contact area between an electronically conducting and an ionically conducting phase is the area where an electrode meets an electrolyte or an electrolyte solution. This area may differ significantly from the geometric, microscopic, real, or true surface area of the electronically conducting solid (the electrode) determined with a variety of experimental methods. This contact area may also differ from the electrochemically active surface area. These different surface or interface areas are relevant in electrochemical energy conversion and storage. They are not necessarily identical; there are even no simple relationships between them. This entry provides an overview of the various terms, briefly describes experimental methods for their determination and puts the data in perspective with respect to electrochemical energy conversion and storage.
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  • 24 Feb 2023
Topic Review
Prosumption as Basic Market Force in Modern Economy
The term “prosumption” is a portmanteau of production and consumption. It refers to a process where a consumer takes over some of the activities previously performed by a producer, usually by directly involving themselves in the design and production of various goods or services. Prosumption is the basic market force in the modern economy.
  • 9.4K
  • 07 Dec 2022
Topic Review Peer Reviewed
Techno-Economic Analysis of State-of-the-Art Carbon Capture Technologies and Their Applications: Scient Metric Review
Carbon dioxide (CO2) emissions are a serious hazard to human life and the ecosystem. This is the reason that many measures have been put in place by the International Energy Agency (IEA) to reduce the anthropogenic-derived CO2 concentration in the atmosphere. Today, the potential of renewable energy sources has led to an increased interest in investment in carbon capture and storage technologies worldwide. The aim of this paper is to investigate state-of-the-art carbon capture and storage (CCS) technologies and their derivations for the identification of effective methods during the implementation of evidence-based energy policies. To this extent, this study reviews the current methods in three concepts: post-combustion; pre-combustion; and oxy-fuel combustion processes. The objective of this study is to explore the knowledge gap in recent carbon capture methods and provide a comparison between the most influential methods with high potential to aid in carbon capture. The study presents the importance of using all available technologies during the post-combustion process. To accomplish this, an ontological approach was adopted to analyze the feasibility of the CCS technologies available on the market. The study findings demonstrate that priority should be given to the applicability of certain methods for both industrial and domestic applications. On the contrary, the study also suggests that using the post-combustion method has the greatest potential, whereas other studies recommend the efficiency of the oxy-fuel process. Furthermore, the study findings also highlight the importance of using life cycle assessment (LCA) methods for the implementation of carbon capture technologies in buildings. This study contributes to the energy policy design related to carbon capture technologies in buildings.
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  • 16 Oct 2023
Topic Review
PERVAINCONSA Scale to Measure Consumer Behavior
The PERVAINCONSA Scale (acrostic formed with the initial letters of the Spanish words “Percepción de Valor”, “Intención de Compra”, “Confianza” and “Satisfacción”) was constructed. It aims to validate an instrument designed to measure the variables value perception, purchase intention, trust, and satisfaction of Micro, Small and Medium Enterprises (MSMEs) dedicated to selling clothing.
  • 9.4K
  • 22 Mar 2022
Topic Review
Cocoa Shell
The positive impact of cocoa shell on nutritional value of food was emphasized, such as increase of fiber content, enrichment with polyphenols, positive impact on glucose metabolism. However, potential shortcomings, such as mycotoxins, PAHs, and microbial contamination are also discussed.
  • 9.4K
  • 28 Oct 2020
Topic Review
Factors Affecting Consumer Food Choice
Understanding individual food choices is critical for transforming the current food system to ensure healthiness of people and sustainability of the planet. Throughout the years, researchers from different fields have proposed conceptual models addressing factors influencing the food choice, recognized as a key leverage to improve planetary and human health. However, a multidisciplinary approach is needed to better understand how different factors are involved and interact with each other in the decision-making process. The present paper reviews and analyzes existing models, providing an intact point-of-view by integrating key elements into a bigger framework. Key determinants of general food choice are identified and categorized, including food-internal factor (sensory and perceptual features), food-external factors (information, social environment, physical environment), personal-state factors (biological features and physiological needs, psychological components, habits and experiences), cognitive factors (knowledge and skills, attitude, liking and preference, anticipated consequences, and personal identity), as well as sociocultural factors (culture, economic variables, political elements). Moreover, possible directions of influence among the factors towards final food choice were discussed. The need of multidisciplinary impulses across research field with the support of empirical data are crucial for understanding factors influencing food choice as well as for enriching existing conceptual models. The framework proposed here would serve as a roadmap for facilitating communications and collaborations between research fields in a structural and systematic way.
  • 9.4K
  • 06 Feb 2021
Topic Review
Ravidassia Religion
The Ravidassia religion, also called Ravidasia Dharm, is an Indian religion, founded in the 14th-century. It is based on the teachings of the 14th century Indian guru Ravidass, revered as a Satguru, particularly by ravidasia community Historically, Ravidassia represented a range of beliefs in the Indian subcontinent, with some devotees of Ravidass counting themselves as Ravidassia, but first formed in the early 20th-century in colonial British India. The Ravidassia community began to take on more cohesion following 1947, and the establishment of successful Ravidassia communities in the diaspora. Ravidassias believe that Ravidas is their Guru (saint) whereas the Sikhs have traditionally considered him as one of many bhagats (holy person). Further, Ravidassias accept living sants of Ravidass Deras as Guru whereas the Sikhs do not, states Ronki Ram. A new Ravidassia religion was launched following an assassination attack on their visiting living Guru Sant Niranjan Dass and his deputy Ramanand Dass in 2009 in Vienna by Sikh militants. Ramanand Dass died from the attack, Niranjan Dass survived his injuries, while over a dozen attendees at the temple were also injured. This triggered a decisive break of the Ravidassia group from the orthodox Sikh structure. Prior to their break from Sikhism, the Dera Bhallan revered and recited the Guru Granth Sahib of Sikhism in Dera Bhallan. However, following their split from mainstream Sikhism, the Dera Bhallan compiled their own holy book based exclusively on Ravidas's teachings, the Amritbani Guru Ravidass Ji, and these Dera Bhallan Ravidassia temples now use this book in place of the Guru Granth Sahib.
  • 9.4K
  • 05 Dec 2022
Topic Review
Hypothetical Construct
In philosophy, a construct is an object which is ideal, that is, an object of the mind or of thought, meaning that its existence may be said to depend upon a subject's mind. This contrasts with any possibly mind-independent objects, the existence of which purportedly does not depend on the existence of a conscious observing subject. Thus, the distinction between these two terms may be compared to that between phenomenon and noumenon in other philosophical contexts and to many of the typical definitions of the terms realism and idealism also. In the correspondence theory of truth, ideas, such as constructs, are to be judged and checked according to how well they correspond with their referents, often conceived as part of a mind-independent reality.
  • 9.4K
  • 23 Nov 2022
Topic Review
Lexical Bundles
The term “lexical bundles” was defined as “recurrent expressions, regardless of their idiomaticity, and regardless of their structural status”. As is well documented, lexical bundles not only contribute to fluent linguistic production but also form essential building blocks of discourse. A good command of lexical bundles could be indicative of a proficient and professional academic writer and is thus considered a pivotal skill for student writers, especially EFL student writers, for achieving sustainable growth of writing competence. Appropriate use of lexical bundles in academic writing helps writers from an academic community demonstrate their research writing ability.
  • 9.4K
  • 17 Jun 2021
Topic Review
Co-Culture System
Co-culture system provides a novel platform to study interaction between different cell types in an in-vitro method. The co-cultures techniques have played key role in the understanding of cell–cell communication and relevant for drug response analysis. 
  • 9.4K
  • 21 Jan 2021
Topic Review
Islam and Secularism
Secularism—i.e. the separation of religion from civic affairs and the state—has been a controversial concept in Islamic political thought, owing in part to historical factors and in part to the ambiguity of the concept itself. In the Muslim world, the notion has acquired strong negative connotations due to its association with removal of Islamic influences from the legal and political spheres under foreign colonial domination, as well as attempts to restrict public religious expression by some secularist nation states. Thus, secularism has often been perceived as a foreign ideology imposed by invaders and perpetuated by post-colonial ruling elites, and is frequently understood to be equivalent to irreligion or anti-religion. Especially in the late 19th to mid-20th century, some Muslim thinkers advocated secularism as a way to strengthen the Islamic world in the face of Russian, British and French colonialism. Some have advocated secularism in the sense of political order that does not impose any single interpretation of sharia (Ali Abdel Raziq and Mahmoud Mohammed Taha); argued that such a political order would not/does not violate Islam (Abdullah Saeed); and that combined with constitutionalism and human rights, is more consistent with Islamic history than modern visions of an Islamic state (Abdullahi Ahmed An-Na'im). Strongly opposed to limiting Islam to matters of personal belief, and strongly advocating an Islam encompassing law, politics, economics, culture and every other aspect of the lives of its citizens, are orthodox Islamic scholars and proponents of Islamism (political Islam). Islamist pioneer Abul A'la Maududi claimed that the goal of secularists was not to ameliorate tensions and divisions in multi-religious societies, but to avoid the "restraints of morality and divine guidance", and thus eliminate "all morality, ethics, or human decency from the controlling mechanisms of society." A number of pre-modern polities in the Islamic world demonstrated some level of separation between religious and political authority, even if they did not adhere to the modern concept of a state with no official religion or religion-based laws. Today, some Muslim-majority countries define themselves as or are regarded as secular. Many of them have a dual legal system in which Muslims can bring familial and financial disputes to sharia courts whose jurisdiction varies from country to country but usually includes marriage, divorce, inheritance, and guardianship.
  • 9.4K
  • 26 Oct 2022
Topic Review
Inelastic Neutron Scattering
Inelastic neutron scattering (INS) is a spectroscopy based on the energy analysis of neutrons after they have been scattered by a sample. A detected energy transfer can be related to a physical interaction of the corresponding atoms with their environment. An energy transfer of several meVs typically arises from vibrations of atoms. Thus, INS provides an amplitude-of-motion and neutron incoherent cross section weighted phonon density of states.  Given the much higher incoherent scattering cross section of hydrogen relative to that of all other elements, INS is particular sensitive to hydrogen based vibrations. The method is widely used in condensed matter physics and solid state chemistry, because the vibrational properties of matter define various physical properties such as the heat capacity. If used as a fingerprint method, INS can be used to characterize chemical bonds both in the bulk as well as on the surface.
  • 9.4K
  • 30 Oct 2020
Topic Review
Control Techniques in Photovoltaic Systems
Complex control structures are required for the operation of photovoltaic electrical energy systems. In this paper, a general review of the controllers used for photovoltaic systems is presented. This entry is based on the most recent papers presented in the literature. The control architectures considered are complex hybrid systems that combine classical and modern techniques, such as artificial intelligence and statistical models. The main contribution of this paper is the synthesis of a generalized control structure and the identification of the latest trends. The main findings are summarized in the development of increasingly robust controllers for operation with improved efficiency, power quality, stability, safety, and economics.
  • 9.4K
  • 19 Feb 2021
Topic Review
Gaulish Language
Gaulish was an ancient Celtic language that was spoken in parts of Continental Europe before and during the period of the Roman Empire. In the narrow sense, Gaulish was the language spoken by the Celtic inhabitants of Gaul (modern-day France, Luxembourg, Belgium, most of Switzerland, Northern Italy, as well as the parts of the Netherlands and Germany on the west bank of the Rhine). In a wider sense, it also comprises varieties of Celtic that were spoken across much of central Europe ("Noric"), parts of the Balkans, and Anatolia ("Galatian"), which are thought to have been closely related. The more divergent Lepontic of Northern Italy has also sometimes been subsumed under Gaulish. Together with Lepontic and the Celtiberian language spoken in the Iberian Peninsula, Gaulish helps form the geographic group of Continental Celtic languages. The precise linguistic relationships among them, as well as between them and the modern Insular Celtic languages, are uncertain and a matter of ongoing debate because of their sparse attestation. Gaulish is found in some 800 (often fragmentary) inscriptions including calendars, pottery accounts, funeral monuments, short dedications to gods, coin inscriptions, statements of ownership, and other texts, possibly curse tablets. Gaulish texts were first written in the Greek alphabet in southern France and in a variety of the Old Italic script in northern Italy. After the Roman conquest of those regions, writing shifted to the use of the Latin alphabet. During his conquest of Gaul, Caesar reported that the Helvetii were in possession of documents in the Greek script, and all Gaulish coins used the Greek script until about 50 BC. Gaulish in Western Europe was supplanted by Vulgar Latin and various Germanic languages from around the 5th century AD onwards. It is thought to have gone extinct some time around the late 6th century.
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  • 01 Dec 2022
Topic Review
Decline of Christianity
The decline of Christianity is an ongoing trend in Europe. Developed countries with good educational facilities in the post-World War II era have shifted towards post-Christian, secular, globalized, multicultural and multifaith societies. Infant baptism has declined in many nations, with thousands of churches closing or merging due to lack of attendees. There is also evidence of decline in North America. Despite the decline, Christianity remains the dominant religion in the Western world, where 70% of the population is nominally Christian.
  • 9.4K
  • 11 Nov 2022
Topic Review
Kiev
Kiev or Kyiv (Ukrainian: Київ; Russian: Киев, romanized: Kiyev) is the capital and most populous city of Ukraine . It is in north-central Ukraine along the Dnieper River. Its population in July 2015 was 2,887,974 (though higher estimated numbers have been cited in the press), making Kiev the seventh-most populous city in Europe. Kiev is an important industrial, scientific, educational and cultural center of Eastern Europe. It is home to many high-tech industries, higher education institutions, and historical landmarks. The city has an extensive system of public transport and infrastructure, including the Kiev Metro. The city's name is said to derive from the name of Kyi, one of its four legendary founders. During its history, Kiev, one of the oldest cities in Eastern Europe, passed through several stages of prominence and obscurity. The city probably existed as a commercial center as early as the 5th century. A Slavic settlement on the great trade route between Scandinavia and Constantinople, Kiev was a tributary of the Khazars, until its capture by the Varangians (Vikings) in the mid-9th century. Under Varangian rule, the city became a capital of the Kievan Rus', the first East Slavic state. Completely destroyed during the Mongol invasions in 1240, the city lost most of its influence for the centuries to come. It was a provincial capital of marginal importance in the outskirts of the territories controlled by its powerful neighbours, first Lithuania, then Poland and Russia. The city prospered again during the Russian Empire's Industrial Revolution in the late 19th century. In 1918, after the Ukrainian National Republic declared independence from Soviet Russia, Kiev became its capital. From 1921 onwards Kiev was a city of Soviet Ukraine, which was proclaimed by the Red Army, and, from 1934, Kiev was its capital. The city was almost completely ruined during World War II but quickly recovered in the postwar years, remaining the Soviet Union's third-largest city. Following the collapse of the Soviet Union and Ukrainian independence in 1991, Kiev remained Ukraine's capital and experienced a steady influx of ethnic Ukrainian migrants from other regions of the country. During the country's transformation to a market economy and electoral democracy, Kiev has continued to be Ukraine's largest and wealthiest city. Its armament-dependent industrial output fell after the Soviet collapse, adversely affecting science and technology, but new sectors of the economy such as services and finance facilitated Kiev's growth in salaries and investment, as well as providing continuous funding for the development of housing and urban infrastructure. Kiev emerged as the most pro-Western region of Ukraine; parties advocating tighter integration with the European Union dominate during elections.
  • 9.4K
  • 10 Nov 2022
Topic Review
Slavic Native Faith's Theology and Cosmology
Slavic Native Faith (Rodnovery) has a theology that is generally monistic, consisting in the vision of an absolute, supreme God (Rod) who begets the universe and lives as the universe (pantheism and panentheism), present in all its phenomena. Polytheism, that is the worship of the gods or spirits, and ancestors, the facets of the supreme Rod generating all phenomena, is an integral part of Rodnovers' beliefs and practices. The swastika-like kolovrat is the symbol of Rodnovery. According to the studies of Boris Rybakov, whirl and wheel symbols, which also include patterns like the "six-petaled rose inside a circle" (e.g. ) and the "thunder mark" (gromovoi znak), represent the supreme Rod and its various manifestations (whether Triglav, Svetovid, Perun or other gods).
  • 9.4K
  • 21 Oct 2022
Topic Review
Big Data Mining
Big data mining (BDM) is an approach that uses the cumulative data mining or extraction techniques on large datasets / volumes of data. It is mainly focused on retrieving relevant and demanded information (or patterns) and thus extracting value hidden in data of an immense volume. BDM draws from the conventional data mining notation but also combines the aspects of big data, i.e. it enables to acquire useful information from databases or data streams that are huge in terms of “big data V’s”, like volume, velocity, and variety.
  • 9.4K
  • 05 Aug 2021
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