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Topic Review
Odal (Rune)
Template:Infobox rune The Elder Futhark Odal rune (ᛟ), also known as the Othala rune, represents the o sound. Its reconstructed Proto-Germanic name is *ōþalan "heritage; inheritance, inherited estate". It was in use for epigraphy during the 3rd to the 8th centuries. It is not continued in the Younger Futhark, disappearing from the Scandinavian record around the 6th century, but it survived in the Anglo-Saxon Futhorc, and expressed the Old English œ phoneme during the 7th and 8th centuries. Its name is attested as ēðel in the Anglo-Saxon manuscript tradition. The odal rune with serifs (feet) is associated with Nazism and is banned in Germany under laws restricting Nazi symbolism, and other, similar organizations. The rune is encoded in Unicode at code point U+16DF: ᛟ.
  • 19.3K
  • 17 Oct 2022
Topic Review
Sustainability Digital Innovations
Sustainability digital innovations is an increasingly present element in contemporary societies. This entry is a reflection on sustainability digital innovations within the context of Society 5.0 and the inherent heuristic potentials of this relationship.
  • 19.3K
  • 29 Oct 2020
Topic Review
Extraction Techniques in Sample Preparation
Sample preparation is the most crucial step in the analytical procedure designed for implementation in any analytical application (food analysis, bionalysis, forensics, toxicology, environmental monitoring etc). It is the limiting factor in chemical analysis since it is time consuming and it can potentially introduce errors. No one can doubt that the best approach would be the direct introduction of the sample to the instrument, however this is rarely feasible. Efficient sample pretreatment is inevitably required as the instrument technology has produced highly sophisticated and sensitive analytical equipment. Hence, the analytical scientists have to develop and apply a suitable sample preparation protocol that ensures that the composition of the sample remains unchanged, no impurities are introduced during handling, all interferences have been left back, the analytes’ concentration is not only at detectable levels, but it can also be quantified precisely and accurately and that the matrix of the sample is compatible with the analytical technique. Extraction techniques are the most powerful tool in hands of the analytical chemists and lab practitioners. Either sorbent based or solvent based, extraction techniques provide the necessary tool that can be used to handle the sample in a way that all information in it can be revealed, all advantages in instrumentation have been exploited to the fullest and the lifetime of the instrument is prolonged in a seamless operation mode.
  • 19.2K
  • 28 Oct 2020
Topic Review
Algal Evolution
Phylogenetically algae is regarded as polyphyletic as its origin cannot be traced back to single common hypothetical ancestor. However, genomic studies on algae suggest that algae evolved through endosymbiosis giving rise to at least eight to nine phyla over a period of time.
  • 19.2K
  • 25 Nov 2020
Topic Review
Timeline of Biotechnology
The historical application of biotechnology throughout time is provided below in chronological order. These discoveries, inventions and modifications are evidence of the application of biotechnology since before the common era and describe notable events in the research, development and regulation of biotechnology.
  • 19.2K
  • 05 Dec 2022
Topic Review Video
Nutritional Interventions
The importance of nutrition in human health is becoming increasingly clear. Despite the growing number of publications in this field, the quality of evidence supporting most nutritional recommendations is classified as "low". To improve the quality of evidence to support nutritional recommendations, the quality of research in this field must be improved. Randomized clinical trials (RCT) are a design that can help to provide high-quality evidence; however, conducting a RCT based on a nutritional intervention can be difficult due to the heterogeneous nature of the intervention and the number of variables that must be considered. Following a review of methodological and ethical standards, as well as four extensions of the CONSORT (Consolidated Standards of Reporting Trials) guidelines applicable to nutritional interventions, a series of definitions, examples, diagrams, and algorithms of key aspects that should be considered when conducting a RCT based on a nutritional intervention were identified.
  • 19.1K
  • 17 Jun 2022
Topic Review
Pi-Stacking
In chemistry, pi stacking (also called π–π stacking) refers to the presumptive attractive, noncovalent interactions (orbital overlap) between the pi bonds of aromatic rings. However this is a misleading description of the phenomena since direct stacking of aromatic rings (the "sandwich interaction") is electrostatically repulsive. What is more commonly observed (see figure to the right) is either a staggered stacking (parallel displaced) or pi-teeing (perpendicular T-shaped) interaction both of which are electrostatic attractive For example, the most commonly observed interactions between aromatic rings of amino acid residues in proteins is a stagered stacked followed by a perpendular orientation. Sandwiched orientations are relatively rare. Pi stacking is repulsive as it places carbon atoms with partial negative charges from one ring on top of other partial negatively charged carbon atoms from the second ring and hydrogen atoms with partial postive charges on top of other hydrogen atoms that likewise carry partial positive charges. In staggered stacking, one of the two aromatic rings is offset sideways so that the carbon atoms with partial negative charge in the first ring are placed above hydrogen atoms with partial positive charge in the second ring so that the electrostatic interactions become attractive. Likewise, pi-teeing interactions in which the two rings are oriented perpendicultar to either other is electrostatically attractive as it places partial postively charged hydrogen atoms in close proximity to partially negatively charged carbon atoms. An alternative explanation for the preference for staggered stacking is due to the balance between van der Waals interactions (attractive dispersion plus Pauli repulsion). These staggered stacking and π-teeing interactions between aromatic rings are important in nucleobase stacking within DNA and RNA molecules, protein folding, template-directed synthesis, materials science, and molecular recognition. Despite the wide use of term pi stacking in the scientific literature, there is no theoretical justification for its use.
  • 19.1K
  • 12 Oct 2022
Topic Review
Corrective Rape
Corrective rape, also called curative or homophobic rape, is a hate crime in which one or more people are raped because of their perceived sexual orientation or gender identity. The common intended consequence of the rape, as seen by the perpetrator, is to turn the person heterosexual or to enforce conformity with gender stereotypes. The term corrective rape was coined in South Africa after well-known cases of corrective rapes of lesbian women such as Eudy Simelane (who was also murdered in the same attack) and Zoliswa Nkonyana became public. Popularisation of the term has raised awareness and encouraged LGBT+ people in countries across the world to come forward with their own stories of being raped as punishment for or in an attempt to change their sexual orientation or gender identity. Although some countries have laws protecting LGBT+ people, corrective rape is often overlooked.
  • 18.9K
  • 09 Oct 2022
Topic Review
Sociology and History
Sociology and History as consolidated scientific and academic projects have maintained a peculiar and paradoxical relationship. The growing disciplinary and subdisciplinary specialisation of these two sciences poses relevant epistemological and methodological challenges in order to face potential situations of isolation, fragmentation and enable the apology of an interdisciplinary perspective characterised by the historicity of social structures, actions and senses.
  • 18.7K
  • 30 Oct 2020
Topic Review
Fish Muscle
Fish muscle, which accounts for 15%–25% of the total protein in fish, is a desirable protein source. Their hydrolysate is in high demand nutritionally as a functional food and thus has high potential added value. The hydrolysate contains physiologically active amino acids and various essential nutrients, the contents of which depend on the source of protein, protease, hydrolysis method, hydrolysis conditions, and degree of hydrolysis.
  • 18.6K
  • 07 Jul 2021
Topic Review
Structure and Chemistry of 3(5)-Substituted Pyrazoles
Pyrazoles are known as versatile scaffolds in organic synthesis and medicinal chemistry, often used as starting materials for the preparation of more complex heterocyclic systems with relevance in the pharmaceutical field. Pyrazoles are also interesting compounds from a structural viewpoint, mainly because they exhibit tautomerism. This phenomenon may influence their reactivity, with possible impact on the synthetic strategies where pyrazoles take part, as well as on the biological activities of targets bearing a pyrazole moiety, since a change in structure translates into changes in properties. Investigations of the structure of pyrazoles that unravel the tautomeric and conformational preferences are therefore of upmost relevance. 3(5)-Aminopyrazoles are largely explored as precursors in the synthesis of condensed heterocyclic systems, namely pyrazolo[1,5-a]pyrimidines.
  • 18.5K
  • 04 Jul 2022
Topic Review
Zodiac
The zodiac is a belt-shaped region of the sky that extends approximately 8° north or south (as measured in celestial latitude) of the ecliptic, the apparent path of the Sun across the celestial sphere over the course of the year. The paths of the Moon and visible planets are within the belt of the zodiac. In Western astrology, and formerly astronomy, the zodiac is divided into twelve signs, each occupying 30° of celestial longitude and roughly corresponding to the following star constellations: Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius, and Pisces. These astrological signs form a celestial coordinate system, or more specifically an ecliptic coordinate system, which takes the ecliptic as the origin of latitude and the Sun's position at vernal equinox as the origin of longitude.
  • 18.5K
  • 31 Oct 2022
Topic Review
Closed Timelike Curves
Closed timelike curves (CTCs) are space-time trajectories that return to their starting point without violating the laws of special relativity. A traveler along a CTC could journey into the future but arrive in its past, creating a possible violation of the principle of causality. Such CTCs occur in Gödel’s rotating universe and many other general relativistic solutions of classical Einstein’s field equations. The chronological protection conjecture suggests that Nature forbids this kind of situation.
  • 18.5K
  • 27 Jan 2021
Topic Review
Social System
A social system refers to a complex network of interrelated social entities, such as individuals, groups, organizations, and institutions, that interact and influence one another within a shared environment or society. These interactions are guided by norms, values, roles, and patterns of behavior, which collectively shape the functioning and structure of the social system. Social systems exhibit patterns of organization, stability, and adaptation, serving various functions and purposes within society.
  • 18.5K
  • 02 Feb 2024
Topic Review
Ivan Illich
Ivan Illich (1926-2002) was a very well-known author, mainly in the 1970s, for his provocative publications, such as Deschooling Society (1970), where he proposed the eradication of the School as an institution.
  • 18.4K
  • 29 Oct 2020
Topic Review
Women in Shinto
Women in Shinto occupy a unique role in the indigenous Japanese traditions of Shinto, including a unique form of participation as temple stewards and shamans, or miko. Though a ban on Shinto priestesses was lifted after 1945, the number of women priests in Shinto is a small fraction of contemporary clergy.
  • 18.4K
  • 17 Oct 2022
Topic Review
Standard Conditions for Temperature and Pressure
Standard temperature and pressure (STP) are standard sets of conditions for experimental measurements to be established to allow comparisons to be made between different sets of data. The most used standards are those of the International Union of Pure and Applied Chemistry (IUPAC) and the National Institute of Standards and Technology (NIST), although these are not universally accepted standards. Other organizations have established a variety of alternative definitions for their standard reference conditions. In chemistry, IUPAC changed the definition of standard temperature and pressure in 1982: STP should not be confused with the standard state commonly used in thermodynamic evaluations of the Gibbs energy of a reaction. NIST uses a temperature of 20 °C (293.15 K, 68 °F) and an absolute pressure of 1 atm (14.696 psi, 101.325 kPa). This standard is also called normal temperature and pressure (abbreviated as NTP). These stated values of STP used by NIST have not been verified and require a source. However, values cited in Modern Thermodynamics with Statistical Mechanics by Carl S. Helrich and A Guide to the NIST Chemistry WebBook by Peter J. Linstrom suggest a common STP in use by NIST for thermodynamic experiments is 298.15 K (25°C, 77°F) and 1 bar (14.5038 psi, 100 kPa). The International Standard Metric Conditions for natural gas and similar fluids are 288.15 K (15.00 °C; 59.00 °F) and 101.325 kPa. In industry and commerce, standard conditions for temperature and pressure are often necessary to define the standard reference conditions to express the volumes of gases and liquids and related quantities such as the rate of volumetric flow (the volumes of gases vary significantly with temperature and pressure): standard cubic meters per second (Sm3/s), and normal cubic meters per second (Nm3/s). However, many technical publications (books, journals, advertisements for equipment and machinery) simply state "standard conditions" without specifying them; often substituting the term with older "normal conditions", or "NC". In special cases this can lead to confusion and errors. Good practice always incorporates the reference conditions of temperature and pressure. If not stated, some room environment conditions are supposed, close to 1 atm pressure, 293 K (20 °C), and 0% humidity.
  • 18.3K
  • 09 Nov 2022
Topic Review
Two-Dimensional Materials
Two-dimensional (2D) materials are defined as crystalline materials consisting of single- or few-layer atoms, in which the in-plane interatomic interactions are much stronger than those along the stacking direction. Since the success of monolayer graphene exfoliation, 2D materials have been extensively studied due to their unique structures and unprecedented properties. Among these fascinating studies, the most predominant focus has been on their atomic structures, defects, and mechanical behaviors and properties, which serve as the basis for the practical applications of 2D materials.
  • 18.3K
  • 07 Jan 2022
Topic Review
Flavonoids—Classification and Natural Sources
       Flavonoids are small molecules, produced de novo by plants as secondary metabolites in response to diverse biotic and abiotic factors. These chemical compounds have a broad spectrum of established health-promoting effects. They are due to their antioxidative, anti-inflammatory, anti-mutagenic, and anti-carcinogenic properties coupled with their capacity to modulate key cellular enzyme functions. Flavonoids are widely distributed chemical compounds in the plant kingdom. Plants are therefore an inexhaustible source of flavonoids.
  • 18.3K
  • 02 Nov 2020
Biography
Jesse Lee Peterson
Jesse Lee Peterson (born May 22, 1949) is an American conservative pundit, minister, author, and media personality. He is the host of The Jesse Lee Peterson Show—a national radio show which airs on Newsmax TV, and The Fallen State TV web series. He is also president and founder of BOND (Brotherhood Organization of a New Destiny), a religious 501(c)(3) non-profit dedicated to "rebuilding the fa
  • 18.3K
  • 27 Dec 2022
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