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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.
  • 10.4K
  • 21 Nov 2022
Topic Review
Dyschronometria
Dyschronometria is a condition of cerebellar dysfunction in which an individual cannot accurately estimate the amount of time that has passed (i.e., distorted time perception). It is associated with cerebellar ataxia, when the cerebellum has been damaged and does not function to its fullest ability. Lesions to the cerebellum can cause dyssynergia, dysmetria, dysdiadochokinesia, dysarthria, and ataxia of stance and gait. Dyschronometria can result from autosomal dominant cerebellar ataxia (ADCA).
  • 10.4K
  • 04 Nov 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.
  • 10.4K
  • 08 Oct 2022
Topic Review
Popular Culture
Popular culture refers to the set of ideas, practices, images, and phenomena that are prevalent and widely accepted within a society at a given point in time. It encompasses various aspects of daily life, including entertainment, fashion, music, sports, and technology, reflecting the shared interests and preferences of the general public. Popular culture is dynamic and evolves over time, influenced by social, political, and technological developments, making it a key area of study within the realm of social science.
  • 10.4K
  • 25 Jan 2024
Topic Review
Ecological Urban Planning and Design
Urbanization is a defining feature of the modern age, yet the current model of urban development profoundly alters the natural environment, often reducing biodiversity and ultimately threatening human wellbeing. An ecologically based urban planning and design paradigm should consider a more harmonious relationship. Through a systematic literature review of 57 papers, this research identified relevant concepts and theories that could underpin this new paradigm. It revealed a noticeable increase in academic interest in this subject since 2013 and the development of concepts and theories that reflect a more holistic socio-ecological systems approach to urban planning and design based on a transdisciplinary integration and synthesis of research. Seven main themes underpin the academic literature: ecosystem services, socio-ecological systems, resilience, biodiversity, landscape, green infrastructure, as well as integrated and holistic approaches. Six of these can be organised into either a sustainability stream or a spatial stream, representing the foundations of a potential new ecological urban planning and design paradigm that applies sustainability-related concepts in a spatial setting. The final theme, integrated and holistic, includes concepts that reflect the fundamental characteristics of this new paradigm, which can be termed ‘urban consonance’
  • 10.4K
  • 29 Oct 2020
Topic Review
Organic Potatoes and Conventional Potatoes
Interest in organic foods is increasing at a moment when humanity is facing a range of health challenges including the concern that some conventionally produced foods may pose possible adverse effects on human and livestock health. Consumers are showing increasing interest in organically grown potatoes due to their nutritional quality and health protection value.
  • 10.4K
  • 28 Sep 2021
Topic Review
Libra
The constellation Libra, known as the Scales or the Balance, is one of the 12 zodiac constellations representing an inanimate object. It is located in the southern sky and is associated with justice and balance. Libra is depicted as scales held by the Greek goddess of justice, Astraea, and is the only zodiac constellation named after an object rather than an animal or character from mythology.
  • 10.4K
  • 15 Mar 2024
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.
  • 10.4K
  • 08 Jun 2021
Topic Review
Defect Types and Mechanism of Wind Turbine Blades
There are two main reasons for the damage to wind turbine blades. On the one hand, the wind turbine is in a harsh external environment, and the damage faults are directly caused by external factors, such as strong wind, rain or snow, salt fog, lightning strike, freezing, sandstorm, insects, etc. The other is the invisible defects caused by process problems in the technology of man-made manufacturing. These invisible defects are subject to repeated high loads and harsh external environments during the installation and operation of the wind turbine. The gradual expansion of invisible defects can lead to damage. Due to the complexity of the blade material and structure, each damage type may be caused by a combination of causes. Different defects in the production process and different operating conditions will cause different damage types.
  • 10.4K
  • 28 Sep 2022
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.
  • 10.4K
  • 18 Aug 2021
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.
  • 10.4K
  • 08 Oct 2021
Topic Review
Degeneration Theory
Social degeneration was a widely influential concept at the interface of the social and biological sciences in the 18th and 19th centuries. During the 18th century, scientific thinkers including George Louis Leclerc, comte de Buffon, Johann Friedrich Blumenbach, and Immanuel Kant argued that humans shared a common origin but had degenerated over time due to differences in climate. This theory provided an explanation of where humans came from and why some people appeared different from others. In contrast, degenerationists in the 19th century feared that civilization might be in decline and that the causes of decline lay in biological change. These ideas derived from pre-scientific concepts of heredity ("hereditary taint") with Lamarckian emphasis on biological development through purpose and habit. Degeneration concepts were often associated with authoritarian political attitudes, including militarism and scientific racism, and a preoccupation with eugenics. The theory originated in racial concepts of ethnicity, recorded in the writings of such medical scientists as Johann Blumenbach and Robert Knox. From the 1850s, it became influential in psychiatry through the writings of Bénédict Morel, and in criminology with Cesare Lombroso. By the 1890s, in the work of Max Nordau and others, degeneration became a more general concept in social criticism. It also fed into the ideology of ethnic nationalism, attracting, among others, Maurice Barrès, Charles Maurras and the Action Française. Alexis Carrel, a French Nobel Laureate in Medicine, cited national degeneration as a rationale for a eugenics programme in collaborationist Vichy France. The meaning of degeneration was poorly defined, but can be described as an organism's change from a more complex to a simpler, less differentiated form, and is associated with 19th-century conceptions of biological devolution. In scientific usage, the term was reserved for changes occurring at a histological level – i.e. in body tissues. Although rejected by Charles Darwin, the theory's application to the social sciences was supported by some evolutionary biologists, most notably Ernst Haeckel and Ray Lankester. As the 19th century wore on, the increasing emphasis on degeneration reflected an anxious pessimism about the resilience of European civilization and its possible decline and collapse.
  • 10.4K
  • 21 Oct 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.
  • 10.4K
  • 18 Nov 2020
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.
  • 10.4K
  • 27 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.
  • 10.4K
  • 10 Aug 2020
Topic Review
ThinkCentre M Series
The M-series of desktops are part of Lenovo's ThinkCentre product line. Formerly an IBM brand, Lenovo acquired the ThinkCentre desktop brand following its purchase of IBM's Personal Computing Division (PCD) in 2005. Following its acquisition of IBM's PCD, Lenovo has released M-series desktops in multiple form factors, ranging from traditional tower, to small form factor, and all-in-ones (AIOs).
  • 10.3K
  • 02 Nov 2022
Topic Review
Chemical Composition and Quality of Saffron
Saffron is the commercial name for the dried red stigmas of the Crocus sativus L. flower. It is appreciated for adding color, flavor, and a particular aroma to different food dishes or drinks (paella in Spain, Milanese risotto in Italy, lussekatter buns in Sweden, and alcoholic beverages). It is considered a high-priced condiment (1500–2200 euro/kg) due to the considerable labor involved in its production since it requires manual harvesting as well as a laborious handling process (sorting, drying, and storage). Saffron’s principal producers are Iran and Spain, whereas the leading importers are Spain, Hong Kong, and the United States. Saffron’s quality is essential for consumers in the food industry and is based on the concentration of its apocarotenoids and their respective sensory attributes: crocin’s coloring strength, picrocrocin’s bitter taste, and safranal’s aromatic intensity
  • 10.3K
  • 14 Nov 2022
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.
  • 10.3K
  • 29 Sep 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. 
  • 10.3K
  • 13 Apr 2021
Topic Review
Take This Lollipop
Take This Lollipop is a 2011 interactive horror short film and Facebook app written and directed by Jason Zada. It uses the Facebook Connect application to bring viewers themselves into the film, through use of pictures and messages from their own Facebook profiles. Starring actor Bill Oberst Jr. as 'The Facebook Stalker', the film acts to personalize and underscore the dangers inherent in posting too much personal information about oneself on the internet. The information gathered from a viewer's Facebook profile by the film's app is used once, and then deleted. The title is derived from the 1963 song "Please Little Girl Take This Lollipop", written and performed by singer-songwriter Bobby Jameson, which is used in the film. According to Zada, Take This Lollipop was taken offline "a few months" prior to August 2018. The film's website now hosts a Facebook post by him, saying that the data needed had become "quite hard to access" and had affected the functionality of the film.
  • 10.3K
  • 20 Oct 2022
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