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Topic Review
Herfindahl Index
The Herfindahl index (also known as Herfindahl–Hirschman Index, HHI, or sometimes HHI-score) is a measure of the size of firms in relation to the industry and an indicator of the amount of competition among them. Named after economists Orris C. Herfindahl and Albert O. Hirschman, it is an economic concept widely applied in competition law, antitrust and also technology management. It is defined as the sum of the squares of the market shares of the firms within the industry (sometimes limited to the 50 largest firms), where the market shares are expressed as fractions. The result is proportional to the average market share, weighted by market share. As such, it can range from 0 to 1.0, moving from a huge number of very small firms to a single monopolistic producer. Increases in the Herfindahl index generally indicate a decrease in competition and an increase of market power, whereas decreases indicate the opposite. Alternatively, if whole percentages are used, the index ranges from 0 to 10,000 "points". For example, an index of .25 is the same as 2,500 points. The major benefit of the Herfindahl index in relationship to such measures as the concentration ratio is that it gives more weight to larger firms. The measure is essentially equivalent to the Simpson diversity index, which is a diversity index used in ecology; the inverse participation ratio (IPR) in physics; and the effective number of parties index in politics.
  • 3.1K
  • 19 Oct 2022
Topic Review
Cat Senses
Cat senses are adaptations that allow cats to be highly efficient predators. Cats are good at detecting movement in low light, have an acute sense of hearing and smell, and their sense of touch is enhanced by long whiskers that protrude from their heads and bodies. These senses evolved to allow cats to hunt effectively at night.
  • 3.1K
  • 09 Nov 2022
Topic Review
Staphylococcus pseudintermedius
Staphylococcus pseudintermedius is a pathogenic bacterium of concern within the veterinary sector and is involved in numerous infections in canines, including topical infections such as canine pyoderma and otitis externa, as well as systemic infections within the urinary, respiratory and reproductive tract. The high prevalence of methicillin-resistant Staphylococcus pseudintermedius (MRSP) within such infections is a growing concern.
  • 3.1K
  • 14 May 2021
Topic Review
Complementary Foods
Food safety is imperative, especially for infants and young children because of their underdeveloped immune systems. This requires adequate nutritious food with appropriate amounts of macro- and micronutrients. Currently, a well-established system for infant food is enforced by the regulatory bodies, but no clear system exists for complementary food, which is consumed by children from the age of 6 month to 24 months. As the child grows beyond 6 months, the need for nutrients increases, and if the nutritional needs are not fulfilled, it can lead to health problems, such as stunted growth, weak immune system, and cardiovascular diseases. Hence, it is important to have regulatory bodies monitoring complementary food in a similar capacity as is required for infant formula. 
  • 3.1K
  • 23 Sep 2021
Topic Review
Agarose Hydrogels
Numerous compounds present in the ocean are contributing to the development of the biomedical field. Agarose, a polysaccharide derived from marine red algae, plays a vital role in biomedical applications because of its reversible temperature-sensitive gelling behavior, excellent mechanical properties, and high biological activity. Natural agarose hydrogel has a single structural composition that prevents it from adapting to complex biological environments.
  • 3.1K
  • 26 May 2023
Topic Review
Applications of Saponins
Saponins are a diverse group of naturally occurring plant secondary metabolites present in a wide range of foods ranging from grains, pulses, and green leaves to sea creatures. They consist of a hydrophilic sugar moiety linked to a lipophilic aglycone, resulting in an amphiphilic nature and unique functional properties. Their amphiphilic structures enable saponins to exhibit surface-active properties, resulting in stable foams and complexes with various molecules. In the context of food applications, saponins are utilized as natural emulsifiers, foaming agents, and stabilizers. They contribute to texture and stability in food products and have potential health benefits, including cholesterol-lowering and anticancer effects. Saponins possess additional bioactivities that make them valuable in the pharmaceutical industry as anti-inflammatory, antimicrobial, antiviral, and antiparasitic agents to name a few. Saponins can demonstrate cytotoxic activity against cancer cell lines and can also act as adjuvants, enhancing the immune response to vaccines. 
  • 3.1K
  • 11 Sep 2023
Topic Review
Long-Term Memory
Long-term memory (LTM) is the stage of the Atkinson–Shiffrin memory model in which informative knowledge is held indefinitely. It is defined in contrast to short-term and working memory, which persist for only about 18 to 30 seconds. Long-term memory is commonly labelled as explicit memory (declarative), as well as episodic memory, semantic memory, autobiographical memory, and implicit memory (procedural memory).
  • 3.1K
  • 24 Nov 2022
Topic Review
Facioscapulohumeral Muscular Dystrophy
Facioscapulohumeral muscular dystrophy (FSHD)—the worldwide third most common inherited muscular dystrophy caused by the heterozygous contraction of a 3.3 kb tandem repeat (D4Z4) on a chromosome with a 4q35 haplotype—is a progressive genetic myopathy with variable onset of symptoms, distribution of muscle weakness, and clinical severity.  A rough correlation between the phenotypic severity of FSHD and the D4Z4 repeat size has been reported, and the majority of patients with infantile FSHD obtain a very short D4Z4 repeat length (one to three copies, EcoRI size 10–14 kb), in contrast to the classical, slowly progressive, form of FSHD (15–38 kb). With the increasing identifications of case reports and the advance in genetic diagnostics, recent studies have suggested that the variant of FSHD is not a genetically separate entity but a part of the FSHD spectrum. Nevertheless, many questions about the clinical phenotype and natural history of FSHD remain unanswered, limiting evidence-based clinical management.
  • 3.1K
  • 05 Nov 2020
Topic Review
MEMS Acoustic Emission Sensors
Micro-electro-mechanical-systems (MEMS) acoustic emission (AE) sensors are designed to detect active defects in materials with the transduction mechanisms of piezoresistivity, capacitance or piezoelectricity. The majority of MEMS AE sensors are designed as resonators to improve the signal-to-noise ratio. The fundamental design variables of MEMS AE sensors include resonant frequency, bandwidth/quality factor and sensitivity. Micromachining methods have the flexibility to tune the sensor frequency to a particular range, which is important, as the frequency of AE signal depends on defect modes, constitutive properties and structural composition.
  • 3.1K
  • 22 Dec 2020
Topic Review
Climate Change Impacts on Sunflower Plants
Elevated concentrations of atmospheric carbon dioxide (CO2) and increased temperatures, carbon and nitrogen metabolism will  affect the plant’s oxidative state in sunflower (Helianthus annus L.) plants
  • 3.1K
  • 24 Jan 2022
Topic Review
Humboldt Current
The Humboldt Current, also called the Peru Current, is a cold, low-salinity ocean current that flows north along the western coast of South America. It is an eastern boundary current flowing in the direction of the equator, and extends 500–1,000 km (310–620 mi) offshore. The Humboldt Current is named after the Prussian naturalist Alexander von Humboldt. In 1846, von Humboldt reported measurements of the cold-water current in his book Cosmos. The current extends from southern Chile (~45th parallel south) to northern Peru (~4th parallel south) where cold, upwelled, waters intersect warm tropical waters to form the Equatorial Front. Sea surface temperatures off the coast of Peru, around 5th parallel south, reach temperatures as low as 16 °C (61 °F). This is highly uncharacteristic of tropical waters, as most other regions have temperatures measuring above 25 °C (77 °F). Upwelling brings nutrients to the surface, which support phytoplankton and ultimately increase biological productivity. The Humboldt Current is a highly productive ecosystem. It is the most productive eastern boundary current system. It accounts for roughly 18-20% of the total worldwide marine fish catch. The species are mostly pelagic: sardines, anchovies and jack mackerel. The system's high productivity supports other important fishery resources as well as marine mammals (eared seals and cetaceans) and seabirds. Periodically, the upwelling that drives the system's productivity is disrupted by the El Niño-Southern Oscillation (ENSO) event, often with large social and economic impacts. The Humboldt has a considerable cooling influence on the climate of Chile, Peru and Ecuador. It is also largely responsible for the aridity of Atacama Desert in northern Chile and coastal areas of Peru and also of the aridity of southern Ecuador. Marine air is cooled by the current and thus is not conducive to generating precipitation (although clouds and fog are produced).
  • 3.1K
  • 07 Oct 2022
Topic Review
Chinese Hamster Ovary-K1 Cells
CHO cells are epithelial-like cells isolated from Chinese hamster ovary. The original CHO cells are cultured adherently, but they can be cultured in suspension in serum-free medium after acclimation. CHO cells are widely used for the expression of recombinant proteins.
  • 3.1K
  • 18 Sep 2021
Topic Review
Near-Infrared Spectrum of Olive Oils
Olive oil is regarded as one of the healthiest food oils due to its high content in triglycerides with unsaturated acids, mainly oleic acid, and its phenolic composition. The analysis of the physico-chemical parameters of quality of olive oil is still carried out in laboratories using chemicals and generating waste, which is relatively costly and time-consuming. Among the various alternatives for the online or on-site measurement of these parameters, the available literature highlights the use of near-infrared spectroscopy (NIRS). 
  • 3.1K
  • 18 Apr 2022
Topic Review
Substrate
In chemistry, a substrate is typically the chemical species being observed in a chemical reaction, which reacts with a reagent to generate a product. It can also refer to a surface on which other chemical reactions are performed, or play a supporting role in a variety of spectroscopic and microscopic techniques. In synthetic and organic chemistry, the substrate is the chemical of interest that is being modified. In biochemistry, an enzyme substrate is the material upon which an enzyme acts. When referring to Le Chatelier's principle, the substrate is the reagent whose concentration is changed. The term substrate is highly context-dependent.
  • 3.1K
  • 06 Oct 2022
Topic Review
Nine-Point Circle
In geometry, the nine-point circle is a circle that can be constructed for any given triangle. It is so named because it passes through nine significant concyclic points defined from the triangle. These nine points are: The nine-point circle is also known as Feuerbach's circle, Euler's circle, Terquem's circle, the six-points circle, the twelve-points circle, the n-point circle, the medioscribed circle, the mid circle or the circum-midcircle. Its center is the nine-point center of the triangle.
  • 3.1K
  • 19 Oct 2022
Topic Review
L-Asparaginase
l-Asparaginase (ASNase, EC 3.5.1.1) is a tetrameric aminohydrolase enzyme that catalyses the hydrolysis of the amino acid L-Asparagine into ammonia and L-aspartic acid. ASNase is present in different organisms such as bacteria, fungi, plant tissues and algae. ASNase is used in the pharmaceutical field as an anticancer drug for the treatment of acute lymphoblastic leukemia (ALL) and other malignant diseases such as Hodgkin’s disease. In the food sector, ASNase is used to prevent the formation of acrylamide, a toxic compound formed when starch-rich foods are cooked at temperatures above 100 °C. ASNase can also be used as a biosensor for the detection of L-asparagine levels.
  • 3.1K
  • 21 Feb 2021
Topic Review Peer Reviewed
Need for Widely Applicable Cultural Competencies in the Healthcare of Humans and Animals
This entry discusses the importance of cultural competence in the healthcare of humans and animals, its challenges, its mixed research results, and the need for widely applicable competencies. Although there is research evidence showing that cultural competence is linked with patient satisfaction, better doctor–patient relationships, adherence to therapy, and to some extent, better health outcomes, there is a huge variety of models and competencies in the literature, which has sometimes resulted in inclusive outcomes, confusion as to what constitutes the necessary competencies, and patchy implementation. In spite of the development of cultural competence in human healthcare, its implementation in veterinary medicine remains poor. On this note, the aims of this entry are to provide a brief overview of the cultural competence in healthcare and veterinary medicine and education, to outline the important facts, and to highlight the need for more standardisation in implementing and testing widely applicable cultural competencies for both human and veterinary healthcare.
  • 3.1K
  • 07 Aug 2023
Topic Review
Arctic Fox
The Arctic Fox (Vulpes lagopus) is a captivating species uniquely adapted to the harsh Arctic tundra and coastal habitats of the Northern Hemisphere. Renowned for its pristine white fur in winter and gray-brown coat in summer, the Arctic Fox is a master of camouflage in its icy environment. Endowed with specialized behaviors and physical adaptations, such as a thick fur coat, compact body size, and keen hunting skills, the Arctic Fox thrives in one of the most extreme and challenging environments on Earth.
  • 3.1K
  • 08 Mar 2024
Topic Review
Foundational Principles and Adaptation of the Achilles Tendon
Achilles tendinopathy (AT) is defined as consistent pain in the Achilles tendon coupled with a loss of function associated with mechanical loading. Achilles tendinopathy can either be classified as insertional AT (symptoms localized 0–2 cm from the distal insertion; 20–25% of Achilles tendon injuries) or midportion AT (symptoms localized 2–7 cm proximal to the insertion; 55–65% of Achilles tendon injuries).
  • 3.1K
  • 01 Sep 2022
Topic Review
Synthesis of nucleobase-modified RNA oligonucleotides
The review summarizes the methods of site-specific incorporation of nucleobase-modified units into RNA oligomers via the post-synthetic strategy including recently discovered native hypermodified functional groups, fluorescent dyes, photoreactive groups, disulfide crosslinks, and nitroxide spin labels.
  • 3.1K
  • 06 Aug 2020
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