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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

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 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

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".

9.4K
16 Nov 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.

9.4K
16 Oct 2023

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.

9.4K
31 Oct 2022

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

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

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.

9.4K
24 Feb 2023

Topic Review

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

Orgasm (from Greek ὀργασμός, orgasmos; "excitement, swelling") or sexual climax is the sudden discharge of accumulated sexual excitement during the sexual response cycle, resulting in rhythmic, involuntary muscular contractions in the pelvic region characterized by sexual pleasure. Experienced by males and females, orgasms are controlled by the involuntary or autonomic nervous system. They are usually associated with involuntary actions, including muscular spasms in multiple areas of the body, a general euphoric sensation and, frequently, body movements and vocalizations. The period after orgasm (known as the refractory period) is typically a relaxing experience, attributed to the release of the neurohormones oxytocin and prolactin as well as endorphins (or "endogenous morphine"). Human orgasms usually result from physical sexual stimulation of the penis in males (typically accompanying ejaculation) and of the clitoris in females. Sexual stimulation can be by self-practice (masturbation) or with a sex partner (penetrative sex, non-penetrative sex, or other sexual activity). The health effects surrounding the human orgasm are diverse. There are many physiological responses during sexual activity, including a relaxed state created by prolactin, as well as changes in the central nervous system such as a temporary decrease in the metabolic activity of large parts of the cerebral cortex while there is no change or increased metabolic activity in the limbic (i.e., "bordering") areas of the brain. There is also a wide range of sexual dysfunctions, such as anorgasmia. These effects affect cultural views of orgasm, such as the beliefs that orgasm and the frequency or consistency of it are either important or irrelevant for satisfaction in a sexual relationship, and theories about the biological and evolutionary functions of orgasm.

9.4K
30 Nov 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.

9.4K
22 Mar 2022

Topic Review

Hat puzzles are logic problems that date back to as early as 1961. Such hat puzzles, frequently contextualized as prisoners and hats puzzles, are induction puzzles (a kind of logic puzzle) that involve reasoning about the actions of other people, drawing in aspects of Game theory sometimes called the hierarchy of beliefs. There are many variations, but the central theme remains the same. A number of players are each wearing a hat, which may be of various specified colours. Players can see the colours of at least some other players' hats, but not that of their own. With highly restricted communication or none, some of the players must guess the colour of their hat. The problem is to find a strategy for the players to determine the colours of their hats based on the hats they see and what the other players do. In some versions, they compete to be the first to guess correctly; in others, they can work out a strategy beforehand to cooperate and maximize the probability of correct guesses. One variation received some new publicity as a result of Todd Ebert's 1998 Ph.D. thesis at the University of California, Santa Barbara. It is a strategy question about a cooperative game, which has connections to algebraic coding theory.

9.4K
24 Oct 2022

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

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

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

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

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