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Topic Review
Dinosaur Behavior
Dinosaur behavior is difficult for paleontologists to study since much of paleontology is dependent solely on the physical remains of ancient life. However, trace fossils and paleopathology can give insight into dinosaur behavior. Interpretations of dinosaur behavior are generally based on the pose of body fossils and their habitat, computer simulations of their biomechanics, and comparisons with modern animals in similar ecological niches. As such, the current understanding of dinosaur behavior relies on speculation, and will likely remain controversial for the foreseeable future. However, there is general agreement that some behaviors which are common in crocodiles and birds, dinosaurs' closest living relatives, were also common among dinosaurs. Gregarious behavior was common in many dinosaur species. Dinosaurs may have congregated in herds for defense, for migratory purposes, or to provide protection for their young. There is evidence that many types of dinosaurs, including various theropods, sauropods, ankylosaurians, ornithopods, and ceratopsians, formed aggregations of immature individuals. Nests and eggs have been found for most major groups of dinosaurs, and it appears likely that dinosaurs communicated with their young, in a manner similar to modern birds and crocodiles. The crests and frills of some dinosaurs, like the marginocephalians, theropods and lambeosaurines, may have been too fragile to be used for active defense, and so they were likely used for sexual or aggressive displays, though little is known about dinosaur mating and territorialism. Most dinosaurs seem to have relied on land-based locomotion. A good understanding of how dinosaurs moved on the ground is key to models of dinosaur behavior; the science of biomechanics, in particular, has provided significant insight in this area. For example, studies of the forces exerted by muscles and gravity on dinosaurs' skeletal structure have investigated how fast dinosaurs could run, whether diplodocids could create sonic booms via whip-like tail snapping, and whether sauropods could float.
  • 9.5K
  • 31 Oct 2022
Topic Review
Photocatalysts
Photocatalysts indicates the acceleration of a chemical reaction occurring on the surface of a semiconductor material (the catalyst) caused by the presence of light. Illumination of the catalyst causes the generation of free changes (electrons and holes) that can partecipate to chemical reactions, thus causing (or acceleratin) them. Photocatalysis con be used in hydrogen (H2) production (e.g., via water splitting or photo-reforming of organic substrates), CO2 reduction, pollution mitigation and water or air remediation via oxidation (photodegradation) of pollutants. Titanium dioxide (TiO2) is a “benchmark” photocatalyst, thanks to many favorable characteristics.
  • 9.5K
  • 26 May 2021
Topic Review
Nomadic Empire
Nomadic empires, sometimes also called steppe empires, Central or Inner Asian empires, were the empires erected by the bow-wielding, horse-riding, nomadic people in the Eurasian Steppe, from classical antiquity (Scythia) to the early modern era (Dzungars). They are the most prominent example of non-sedentary polities. Some nomadic empires consolidated by establishing a capital city inside a conquered sedentary state and then exploiting the existing bureaucrats and commercial resources of that non-nomadic society. In such a scenario, the originally nomadic dynasty may become culturally assimilated to the culture of the occupied nation before it is ultimately overthrown. Ibn Khaldun (1332–1406) described a similar cycle on a smaller scale in 1377 in his Asabiyyah theory. Historians of the early medieval period may refer to these polities as "khanates" (after khan, the title of their rulers). After the Mongol conquests of the 13th century the term orda ("horde") also came into use — as in "Golden Horde".
  • 9.5K
  • 25 Nov 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.
  • 9.5K
  • 24 Feb 2023
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.
  • 9.5K
  • 05 Dec 2022
Topic Review
Spirit Spouse
The spirit spouse is one of the most widespread elements of shamanism, distributed through all continents and at all cultural levels. Often, these spirit husbands/wives are seen as the primary helping spirits of the shaman, who assist them in their work, and help them gain power in the world of spirit. The relationships shamans have with their spirit spouses may be expressed in romantic, sexual, or purely symbolic ways, and may include gender transformation as a part of correctly pairing with their "spouse". Shamans report engaging with their spirit spouses through dreams, trance, and other ritual elements. In some cultures, gaining a spirit spouse is a necessary and expected part of initiation into becoming a shaman. Evidence of spirit spouses may be seen in non-shamanic cultures as well, including dreams about Christ by nuns, who are considered to be "brides of Christ".
  • 9.5K
  • 16 Nov 2022
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.
  • 9.5K
  • 01 Dec 2022
Topic Review
Nestorianism
Nestorianism is a Christian theological doctrine that upholds several distinctive teachings in the fields of Christology and Mariology. It opposes the concept of hypostatic union and emphasizes a radical distinction between two natures (human and divine) of Jesus Christ. That Christological position is defined as radical dyophisitism. Nestorianism was named after Christian theologian Nestorius (386–450), Patriarch of Constantinople from 428 to 431, who was influenced by Christological teachings of Theodore of Mopsuestia at the School of Antioch. Nestorius' teachings brought him into conflict with other prominent church leaders, most notably Cyril of Alexandria, who criticized especially his rejection of the title Theotokos ("Mother of God") for Mary, the mother of Jesus. Nestorius and his teachings were eventually condemned as heretical at the Council of Ephesus in 431, and again at the Council of Chalcedon in 451, which led to the Nestorian Schism; churches supporting Nestorian teachings broke with the rest of the Christian Church. Following that, many of Nestorius's supporters relocated to the Sasanian Empire, where they affiliated with the local Christian community, known as the Church of the East. Over the next decades the Church of the East became increasingly Nestorian in doctrine, leading to it becoming known alternatively as the Nestorian Church.
  • 9.5K
  • 25 Nov 2022
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).
  • 9.5K
  • 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).
  • 9.5K
  • 31 Oct 2022
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.
  • 9.5K
  • 07 Dec 2022
Topic Review
Iron-Containing Oral Contraceptives
Oral contraceptive use has been associated with decreased menstrual blood losses; thus, can independently reduce the risk of anemia and iron deficiency in women. Manufacturers have recently started to include supplemental iron in the non-hormonal placebo tablets of some contraceptives. 
  • 9.5K
  • 15 Jul 2021
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).
  • 9.5K
  • 21 Oct 2022
Topic Review
Eosinophil Structure and Biology
Eosinophils are granulocytes with unique biology. The fact that these cells have been largely preserved during evolution strongly suggests that they play relevant physiological functions. Eosinophils have traditionally been classified as effector cells with prevalent cytotoxic activity, although recent evidence indicates that these cells may play a role in a wide range of homeostatic and regulatory functions.
  • 9.5K
  • 09 Sep 2022
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.
  • 9.5K
  • 22 Mar 2022
Topic Review
Kubota Engines
Kubota engines are diesel and spark ignition engines manufactured by Kubota Corporation. Besides gasoline-fueled for spark ignition engines, the company produces dual fuel, LPG-fueled, and natural-gas-fueled engines as well. The engines are widely used in various forms, such as: agricultural equipments, construction equipments, gensets, tractors, and marine propulsion. Beta Marine, an international company providing marine propulsion engines, uses various Kubota engines for fresh water and sea-going boats of various sizes.
  • 9.5K
  • 03 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.
  • 9.5K
  • 17 Jun 2021
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.
  • 9.5K
  • 06 Feb 2021
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 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.
  • 9.4K
  • 16 Oct 2023
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