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Topic Review
Bias Temperature Instability of MOSFETs
CMOS technology dominates the semiconductor industry, and the reliability of MOSFETs is a key issue. Negative bias temperature instability (NBTI) and positive bias temperature instability (PBTI) mainly degrade the performance of pMOSFETs and nMOSFETs, respectively. 
  • 10.3K
  • 13 May 2022
Topic Review Peer Reviewed
Green Building Rating Systems (GBRSs)
Green Building Rating Systems (GBRSs) are typically third-party, voluntary, and market driven standards that measure buildings’ sustainability level by multi-criteria assessment, and encourage the adoption of environmentally, socially and economically sustainable practices in design, construction and operation of buildings (or neighborhoods). GBRSs aim at guiding and assessing the project throughout all its life cycle, thus limiting the negative impact on the environment, as well as on the building occupants’ health and well-being, and even reducing operational costs. Hundreds of GBRSs are now available worldwide, varying in approaches, application processes, and evaluation metrics. BREEAM, CASBEE, Green Star and LEED are among the most applied worldwide. Despite some differences, they all adhere to the same general evaluation structure: project performances ares measured using a set of relevant indicators, grouped per topics such as water management, energy use, materials, site qualities. Each assessed requirement is assigned a score/judgment, the total of which determines the level of sustainability achieved. In addition to regular updates, a current trend is to improve the effectiveness of protocols, making them more comprehensive and accurate, while keeping them easy to use.
  • 10.3K
  • 13 Apr 2022
Topic Review
Human Sex Ratio
In anthropology and demography, the human sex ratio is the ratio of males to females in a population. More data are available for humans than for any other species, and the human sex ratio is more studied than that of any other species, but interpreting these statistics can be difficult. Like most sexual species, the sex ratio in humans is close to 1:1. In humans, the natural ratio between males and females at birth is slightly biased towards the male sex, being estimated to be about 1.05 or 1.06 or within a narrow range from 1.03 to 1.06 males/per female born. Sex imbalance may arise as a consequence of various factors including natural factors, exposure to pesticides and environmental contaminants, war casualties, sex-selective abortions, infanticides, aging, gendercide and problems with birth registration. The sex ratio for the entire world population is 100 males to 100 females (2021 est.). Human sex ratios, either at birth or in the population as a whole, are reported in any of four ways: the ratio of males to females, the ratio of females to males, the proportion of males, or the proportion of females. If there are 108,000 males and 100,000 females the ratio of males to females is 1.080 and the proportion of males is 51.9%. Scientific literature often uses the proportion of males. This article uses the ratio of males to females, unless specified otherwise.
  • 10.3K
  • 08 Oct 2022
Topic Review
Enzymatic Reactions in Honey
Honey is known for its content of biomolecules, such as enzymes. The enzymes of honey originate from bees, plant nectars, secretions or excretions of plant-sucking insects, or microorganisms such as yeasts. Honey can be characterized by enzyme-catalyzed and non-enzymatic reactions. Notable examples of enzyme-catalyzed reactions are the production of hydrogen peroxide through glucose oxidase activity and the conversion of hydrogen peroxide to water and oxygen by catalase enzymes. 
  • 10.2K
  • 19 Aug 2022
Topic Review
DISC Assessment
DISC is a behaviour self-assessment tool originally based on the 1928 DISC emotional and behavioural theory of psychologist William Moulton Marston, which centred on four personality traits: Dominance, Influence, Steadiness, and Compliance. This theory was then developed into a behavioural assessment tool by industrial psychologist Walter Vernon Clarke. Personality expert and researcher, Merrick Rosenberg, notably innovated on the contemporary application of the DISC model as it applies to team development, interpersonal relationships, and American presidential campaigns. DISC has not been scientifically evaluated.
  • 10.2K
  • 27 Nov 2025
Biography
E. Michael Jones
Eugene Michael Jones (born May 4, 1948) is an American writer, former professor, media commentator and the current editor of Culture Wars magazine (formerly Fidelity Magazine). Jones is known for his writings from a perspective which defends the Catholic Church in American society and overviews the decline of the Catholic communities which were assimilated into the secular American mainstream af
  • 10.2K
  • 29 Dec 2022
Topic Review
Aspartic Acid Production
Aspartic acid, or “aspartate,” is a non-essential, four carbon amino acid produced and used by the body in two enantiomeric forms: L-aspartic acid and D-aspartic acid. The L-configuration of amino acids is the dominant form used in protein synthesis; thus, L-aspartic acid is by far the more common configuration. However, D-aspartic acid is one of only two known D-amino acids biosynthesized by eukaryotes. While L-aspartic acid is used in protein biosynthesis and neurotransmission, D-aspartic acid is associated with neurogenesis and the endocrine system. Aspartic acid production and use has been growing in recent years. 
  • 10.2K
  • 13 Apr 2021
Topic Review
Optical Phase Shifters
Optical phase shifters have the functionality to control the phase of light by a change in the effective refractive index. In a Si photonics platform, it is an essential part composing optical modulators as well as switches in Si photonics. The realization of a silicon optical phase shifter marked a cornerstone for the development of silicon photonics, and it is expected that optical interconnects based on the technology relax the explosive datacom growth in data centers. High-performance silicon optical modulators and switches, integrated into a chip, play a very important role in optical transceivers, encoding electrical signals onto the light at high speed and routing the optical signals, respectively. The development of the devices is continuously required to meet the ever-increasing data traffic at higher performance and lower cost.
  • 10.2K
  • 08 Jun 2021
Topic Review
Carbonaceous Biochemical Oxygen Demand
Carbonaceous biochemical oxygen demand or CBOD is a method defined test measured by the depletion of dissolved oxygen by biological organisms in a body of water in which the contribution from nitrogenous bacteria has been suppressed. CBOD is a method defined parameter is widely used as an indication of the pollutant removal from wastewater. It is listed as a conventional pollutant in the U.S. Clean Water Act.
  • 10.2K
  • 21 Nov 2022
Topic Review
Dunkleosteus
Dunkleosteus is an extinct genus of large armored, jawed fishes that existed during the Late Devonian period, about 382–358 million years ago. It consists of ten species, some of which are among the largest placoderms to have ever lived: D. terrelli, D. belgicus, D. denisoni, D. marsaisi, D. magnificus, D. missouriensis, D. newberryi, D. amblyodoratus, and D. raveri. The largest and most well known species is D. terrelli, which grew up to 8.79 m (28.8 ft) long and 4 t (4.4 short tons) in weight. Dunkleosteus could quickly open and close its jaw, like modern-day suction feeders, and had a bite force of 6,000 N (612 kgf; 1,349 lbf) at the tip and 7,400 N (755 kgf; 1,664 lbf) at the blade edge. Numerous fossils of the various species have been found in North America, Poland , Belgium, and Morocco.
  • 10.2K
  • 16 Nov 2022
Topic Review
Salinity and Turbidity in the Red Sea
Several industrial and scientific underwater applications require high-speed wireless connectivity. Acoustic communications have low data rates and high latency, whereas attenuation in seawater severely limits radio frequency communications. Optical wireless communication is a promising solution, with high transmission rates (up to Gb/s) and little attenuation in water at visible wavelengths.
  • 10.2K
  • 08 Oct 2022
Topic Review
Hippocrates
Hippocrates of Kos (/hɪˈpɒkrətiːz/; Greek: Ἱπποκράτης ὁ Κῷος, translit. Hippokrátēs ho Kṓos; c. 460 – c. 370 BC), also known as Hippocrates II, was a Greek physician of the Age of Pericles (Classical Greece), who is considered one of the most outstanding figures in the history of medicine. He is often referred to as the "Father of Medicine" in recognition of his lasting contributions to the field as the founder of the Hippocratic School of Medicine. This intellectual school revolutionized Ancient Greek medicine, establishing it as a discipline distinct from other fields with which it had traditionally been associated (theurgy and philosophy), thus establishing medicine as a profession. However, the achievements of the writers of the Corpus, the practitioners of Hippocratic medicine, and the actions of Hippocrates himself were often conflated; thus very little is known about what Hippocrates actually thought, wrote, and did. Hippocrates is commonly portrayed as the paragon of the ancient physician and credited with coining the Hippocratic Oath, which is still relevant and in use today. He is also credited with greatly advancing the systematic study of clinical medicine, summing up the medical knowledge of previous schools, and prescribing practices for physicians through the Hippocratic Corpus and other works.
  • 10.2K
  • 19 Oct 2022
Topic Review
Urinary Tract Infection
Urinary tract infection (UTI) is a common bacterial infection of the urethra, bladder, ureters, and the kidneys. A diagnosis of a positive UTI is any pathogen with a bacterial load of greater than 100,000 CFU/mL in the urine. A bacterial load under 100,000 CFU/mL is considered a negative UTI result. Escherichia coli (E.coli) is the most common pathogen that infects the urinary tract.
  • 10.2K
  • 10 Aug 2020
Topic Review
Cheilitis
Cheilitis is a medical condition characterized by inflammation of the lips. The inflammation may include the perioral skin (the skin around the mouth), the vermilion border, or the labial mucosa. The skin and the vermilion border are more commonly involved, as the mucosa is less affected by inflammatory and allergic reactions. Cheilitis is a general term, and there are many recognized types and different causes. According to its onset and course, cheilitis can be either acute or chronic. Most cheilitis is caused by exogenous factors such as dryness (chapping) and acute sun exposure. Allergic tests may identify allergens that cause cheilitis.
  • 10.2K
  • 25 Nov 2022
Topic Review
Concept of Human Flourishing
Human flourishing is a thriving concept, whose use has greatly increased among academic researchers from a variety of fields, from the arts and humanities and psychology to the social and environmental sciences and economics. The rise of the concept was sparked by the positive psychology movement, which based it primarily on subjective and individual well-being; however, it was soon taken up by other currents, such as capabilities theory, reaching many social and collective concerns. Since 2016, the philosophical roots have especially energized the concept, maintaining the expansion of its use in fields related to the application of knowledge and management. 
  • 10.2K
  • 01 Mar 2022
Topic Review
Roasting Processes for Lithium Extraction
This entry describes the main thermal treatments for processing spodumene in order to get easier lithium extraction by hydrometallurgical routes. It shows the importance of the thermal treatment and the need to reduce the energy consumption of this operation.
  • 10.2K
  • 18 Nov 2020
Topic Review
Magnetic Potential
The term magnetic potential can be used for either of two quantities in classical electromagnetism: the magnetic vector potential, or simply vector potential, A; and the magnetic scalar potential ψ. Both quantities can be used in certain circumstances to calculate the magnetic field B. The more frequently used magnetic vector potential is defined so that its curl is equal to the magnetic field: [math]\displaystyle{ \nabla \times \mathbf{A}=\mathbf{B}\, }[/math]. Together with the electric potential φ, the magnetic vector potential can be used to specify the electric field E as well. Therefore, many equations of electromagnetism can be written either in terms of the fields E and B, or equivalently in terms of the potentials φ and A. In more advanced theories such as quantum mechanics, most equations use potentials rather than fields. The magnetic scalar potential ψ is sometimes used to specify the magnetic H-field in cases when there are no free currents, in a manner analogous to using the electric potential to determine the electric field in electrostatics. One important use of ψ is to determine the magnetic field due to permanent magnets when their magnetization is known. With some care the scalar potential can be extended to include free currents as well. Historically, Lord Kelvin first introduced vector potential in 1851, along with the formula relating it to the magnetic field.
  • 10.2K
  • 29 Sep 2022
Topic Review
Gramian Matrix
In linear algebra, the Gram matrix (or Gramian matrix, Gramian) of a set of vectors [math]\displaystyle{ v_1,\dots, v_n }[/math] in an inner product space is the Hermitian matrix of inner products, whose entries are given by [math]\displaystyle{ G_{ij}=\langle v_i, v_j \rangle }[/math]. An important application is to compute linear independence: a set of vectors are linearly independent if and only if the Gram determinant (the determinant of the Gram matrix) is non-zero. It is named after Jørgen Pedersen Gram.
  • 10.2K
  • 27 Oct 2022
Topic Review
Rolling Circle Amplification
Rolling circle amplification (RCA) is an isothermal enzymatic process in which a short nucleic acid primer is amplified to form a long single-stranded nucleic acid using a circular template and special nucleic acid polymerases. Furthermore, this approach can be further engineered into a device for point-of-need monitoring of environmental pollutants.
  • 10.1K
  • 08 Oct 2021
Topic Review
Influence Radius of Pumping Well
The influence radius was originally used in the calculation of some hydrogeological parameters but, owing to various coincidences that occur in practical situations, it has been considered that the parameterized influence radius is reasonable and convenient for calculations pertaining to actual production problems, and this misconception has perpetuated. However, by considering the continuity principle of flow, it can be proven that the parameterized influence radius does not exist. The influence radius is essentially the distance in the time–distance problem in physics and is influenced by the hydrogeological conditions and pumping conditions, which is different from the hydrogeological parameters reflecting the natural properties of aquifers, such as the porosity, specific yield, and hydraulic conductivity.
  • 10.1K
  • 18 Aug 2021
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