Your browser does not fully support modern features. Please upgrade for a smoother experience.
Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort by:
Most Viewed Latest Alphabetical (A-Z) Alphabetical (Z-A)
Filter:
All Topic Review Biography Peer Reviewed Entry Video Entry
Topic Review Peer Reviewed
History and Trends in U.S. High School Science Course Taking
This entry describes high school science course taking in the United States (U.S.). High school science course taking refers to the selection, enrollment, and completion of science-related coursework during grades nine through twelve. It encompasses both the timing, quantity, and the rigor (or level of challenge) of science courses. Science course taking in high school includes both foundational or core courses like biology, chemistry, physics, and environmental science. Students may also take advanced science courses such as Advanced Placement (AP), (International Baccalaureate (IB), career and technical education (CTE) or applied, and dual credit or dual enrollment science courses. Some advanced courses meet core course requirements (e.g., AP Physics). This entry focuses on core science course taking, and the distinction between core or advanced core is beyond its scope. A discussion of CTE and dual credit or dual enrollment science course taking is also beyond the entry’s scope. The significant variability in core high school science course taking and historic unequal distribution of opportunities highlights the need for ongoing monitoring of factors influencing course taking to promote equity in access and outcomes. This entry presents a brief history of standards and graduation requirements surrounding high school science course taking, then briefly reviews science course pathways classifications and current trends in course enrollment and completion. A review of current trends in the context of historical developments can help the high school science education policy and practice field take stock of some of the factors that influence current patterns. The entry is written with a lens towards broadening participation in science, technology, engineering, and mathematics (STEM) fields and equity.
  • 2.1K
  • 10 Mar 2025
Topic Review
Oral Mucosal Epithelial Cells
The corneal surface is an essential organ necessary for vision, and its clarity must be maintained. The corneal epithelium is renewed by limbal stem cells, located in the limbus and in palisades of Vogt. Palisades of Vogt maintain the clearness of the corneal epithelium by blocking the growth of conjunctival epithelium and the invasion of blood vessels over the cornea. The limbal region can be damaged by chemical burns, physical damage (e.g., by contact lenses), congenital disease, chronic inflammation, or limbal surgeries. The degree of limbus damage is associated with the degree of limbal stem cells deficiency (partial or total). For a long time, the only treatment to restore vision was grafting part of the healthy cornea from the other eye of the patient or by transplanting a cornea from cadavers. The regenerative medicine and stem cell therapies have been applied to restore normal vision using different methodologies. The source of stem cells varies from embryonic stem cells, mesenchymal stem cells, to induced pluripotent stem cells. This review focuses on the use of oral mucosa epithelial stem cells and their use in engineering cell sheets to treat limbal stem cell deficient patients.
  • 2.1K
  • 30 Oct 2020
Topic Review
Intrusion Detection Systems
Intrusion detection systems and intrusion prevention systems are to prevent network intruders' attack and malicious compliance. Network communities have produced benchmark datasets available for researchers to improve the accuracy of intrusion detection systems. The scientific community has presented data mining and machine learning-based mechanisms to detect intrusion with high classification accuracy. 
  • 2.1K
  • 21 Sep 2021
Topic Review
Diversity Jurisdiction
In the law of the United States, diversity jurisdiction is a form of subject-matter jurisdiction in civil procedure in which a United States district court in the federal judiciary has the power to hear a civil case when the amount in controversy exceeds $75,000 and where the persons that are parties are "diverse" in citizenship or state of incorporation (for corporations being legal persons), which generally indicates that they differ in state and/or nationality. Diversity jurisdiction and federal-question jurisdiction (jurisdiction over issues arising under federal law) constitute the two primary categories of subject matter jurisdiction in U.S. federal courts. The United States Constitution, in Article III, § 2, gives the Congress the power to permit federal courts to hear diversity cases through legislation authorizing such jurisdiction. The provision was included because the Framers of the Constitution were concerned that when a case is filed in one state, and it involves parties from that state and another state, the state court might be biased toward the party from that state. Congress first exercised that power and granted federal trial circuit courts diversity jurisdiction in the Judiciary Act of 1789. Diversity jurisdiction is currently codified at 28 U.S.C. § 1332. In 1969, the American Law Institute explained in a 587-page analysis of the subject that diversity is the "most controversial" type of federal jurisdiction, because it "lays bare fundamental issues regarding the nature and operation of our federal union".
  • 2.1K
  • 18 Oct 2022
Topic Review
Excoriation Disorder
Excoriation disorder is an obsessive-compulsive spectrum mental disorder that is characterized by the repeated urge or impulse to pick at one's own skin to the extent that either psychological or physical damage is caused.
  • 2.1K
  • 15 Nov 2022
Topic Review
ACID (Computer Science)
In computer science, ACID (Atomicity, Consistency, Isolation, Durability) is a set of properties of database transactions intended to guarantee validity even in the event of errors, power failures, etc. In the context of databases, a sequence of database operations that satisfies the ACID properties (and these can be perceived as a single logical operation on the data) is called a transaction. For example, a transfer of funds from one bank account to another, even involving multiple changes such as debiting one account and crediting another, is a single transaction. In 1983, Andreas Reuter and Theo Härder coined the acronym ACID as shorthand for Atomicity, Consistency, Isolation, and Durability, building on earlier work by Jim Gray who enumerated Atomicity, Consistency, and Durability but left out Isolation when characterizing the transaction concept. These four properties describe the major guarantees of the transaction paradigm, which has influenced many aspects of development in database systems. According to Gray and Reuter, IMS supported ACID transactions as early as 1973 (although the term ACID came later).
  • 2.1K
  • 23 Nov 2022
Topic Review
Scanner (Radio)
A scanner (also referred to a police scanner, police scanner radio or radio scanner) is a radio receiver that can automatically tune, or scan, two or more discrete frequencies, stopping when it finds a signal on one of them and then continuing to scan other frequencies when the initial transmission ceases. The terms radio scanner or police scanner generally refer to a communications receiver that is primarily intended for monitoring VHF and UHF landmobile radio systems, as opposed to, for instance, a receiver used to monitor international shortwave transmissions. More often than not, these scanners can also tune to different types of modulation as well (AM, FM, WFM, etc.). Early scanners were slow, bulky, and expensive. Today, modern microprocessors have enabled scanners to store thousands of channels and monitor hundreds of channels per second. Recent models can follow trunked radio systems and decode APCO-P25 digital transmissions. Both hand held and desktop models are available. Scanners are often used to monitor police, fire and emergency medical services. Radio scanning serves an important role in the fields of journalism and crime investigation, as well as a hobby for many people around the world.
  • 2.1K
  • 24 Nov 2022
Topic Review
Tumor-Associated Macrophages in Targeting Solid Cancers
Macrophages are effector cells of the innate immune system, which can play a crucial role in the generation of anti-tumor immunity through their ability to phagocytose cancer cells and present tumor antigens to the cells of adaptive immunity. However, the macrophages that are recruited to the tumor microenvironment predominantly play pro-tumorigenic roles. Several strategies targeting pro-tumorigenic functions and harnessing the anti-tumorigenic properties of macrophages have shown promising results in preclinical studies, and a few of them have also advanced to clinical trials. 
  • 2.1K
  • 06 Jan 2023
Biography
Michael E. Mann
Michael Evan Mann (born December 28, 1965) is an American climatologist and geophysicist,[1] currently director of the Earth System Science Center at Pennsylvania State University, who has contributed to the scientific understanding of historic climate change based on the temperature record of the past thousand years. He has pioneered techniques to find patterns in past climate change, and to is
  • 2.1K
  • 10 Nov 2022
Topic Review
The Mechanisms of Autism
Autism is a neurodevelopmental condition that starts in childhood and continues into adulthood. The core characteristics include difficulties with social interaction and communication, together with restricted and repetitive behaviours. There are a number of key abnormalities of brain structure and function that trigger these behavioural patterns, including an imbalance of functional connectivity and synaptic transmission, neuronal death, gliosis and inflammation. In addition, autism has been linked to alterations in the gut microbiome.
  • 2.1K
  • 04 Nov 2022
Topic Review
PDE4 Inhibitors
Cyclic nucleotide phosphodiesterases 4 (PDE4) are a family of enzymes which specifically promote the hydrolysis and degradation of cAMP. The inhibition of PDE4 enzymes has been widely investigated as a possible alternative strategy for the treatment of a variety of respiratory diseases, including chronic obstructive pulmonary disease and asthma, as well as psoriasis and other autoimmune disorders.
  • 2.1K
  • 21 Jul 2023
Topic Review
Bisphenol A
Bisphenol A (BPA) is an oestrogenic endocrine disruptor widely used in the production of certain plastics, e.g., polycarbonate, hard and clear plastics, and epoxy resins that act as a protective coating for food and beverage cans. Human exposure to this chemical is thought to be ubiquitous. BPA alters endocrine function, thereby causing many diseases in human and animals. In the last few decades, studies exploring the mechanism of BPA activity revealed a direct link between BPA induced oxidative stress and disease pathogenesis. Antioxidants, reducing agents that prevent cellular oxidation reactions, can protect BPA toxicity. Although the important role of antioxidants in minimizing BPA stress has been demonstrated in many studies, a clear consensus on the associated mechanisms is needed, as well as the directives on their efficacy and safety. Herein, considering the distinct biochemical properties of BPA and antioxidants, we provide a framework for understanding how antioxidants alleviate BPA‐associated stress. We summarize the current knowledge on the biological function of enzymatic and non‐enzymatic antioxidants, and discuss their practical potential as BPA‐detoxifying agents.
  • 2.1K
  • 26 Oct 2020
Topic Review
Police Use of Force Models
Recent calls for widespread police reform include re-examination of existing training and practice surrounding the use of force (UOF, e.g., verbal and non-verbal communication, physical tactics, firearms). Visual models representing police UOF decision-making are used for both police training and public communication. However, most models have not been empirically developed or assessed in either the applied police or vision science literatures, representing significant gaps in knowledge. Based on a critical appraisal of the visual features of common police UOF models, the current entry concludes with evidence-based recommendations for effective model design that accurately reflects the complexity and dynamism of police UOF decision-making in both police training and public communication contexts. 
  • 2.1K
  • 20 Feb 2021
Topic Review
Materials for Lithium-Ion Batteries
Lithium-ion batteries (LIBs) are the most commonly used ESS in modern society, mainly due to their high specific capacity, making them appropriate for small and light portable devices without limiting their performance. LIBs are also characterized by prolonged cycle life and no memory effects. These are important advantages that increased the use of LIBs, leading to a progressive replacement of previous technologies, such as nickel–cadmium and nickel–metal hydride batteries, which are less efficient, in particular for small device applications.
  • 2.1K
  • 21 Jun 2021
Topic Review
Methionine Dependence of Cancer
Tumorigenesis is accompanied by the reprogramming of cellular metabolism. The shift from oxidative phosphorylation to predominantly glycolytic pathways to support rapid growth is well known and is often referred to as the Warburg effect. However, other metabolic changes and acquired needs that distinguish cancer cells from normal cells have also been discovered. The dependence of cancer cells on exogenous methionine is one of them and is known as methionine dependence or the Hoffman effect. This phenomenon describes the inability of cancer cells to proliferate when methionine is replaced with its metabolic precursor, homocysteine, while proliferation of non-tumor cells is unaffected by these conditions. Surprisingly, cancer cells can readily synthesize methionine from homocysteine, so their dependency on exogenous methionine reflects a general need for altered metabolic flux through pathways linked to methionine.
  • 2.1K
  • 30 Jun 2021
Topic Review
Golden Berry Fruit and Insulin
La baya dorada (Physalis peruviana L.) es una fruta de gran importancia comercial en algunos países africanos y latinoamericanos, donde se consume localmente y con frecuencia se exporta a los mercados del norte, principalmente Europa y Estados Unidos. Esta fruta tradicionalmente reporta características nutricionales, antioxidantes y fitoquímicas en múltiples países, variedades y estados de madurez. El fruto de Physalis peruviana L. contiene una amplia variedad de compuestos bioquímicos.Los witanólidos y sus derivados son los metabolitos más emblemáticos de la especie Physalis, y se ha demostrado que ejercen una amplia gama de actividades farmacológicas in vitro, como inmunomoduladores, inhibidores de la angiogénesis, anticolinesterasa, antioxidantes, antibacterianos y en algunos casos, sus extractos han mostrado citotoxicidad. hacia las células cancerosas. Esta familia de compuestos con columna vertebral esteroidal ha llamado la atención de los farmacólogos, ya que estas lactonas esteroides llamadas conhanólidos y sus derivados se concentran principalmente en las partes aéreas de las plantas, como las hojas. También se detectaron en la pulpa de la fruta, pero en concentraciones bajas y probablemente no estén biodisponibles como tales después de la ingestión oral.Pero la baya dorada es rica en carotenoides, sesquiterpenoides, fitoesteroles entre otros que pueden ser responsables del efecto en la salud observado.
  • 2.1K
  • 30 Sep 2021
Topic Review
Postharvest Ultraviolet Radiation in Fruit and Vegetables
Ultraviolet (UV) radiation comprises the region of the electromagnetic spectrum (EM) between visible light and X-rays (100–400 nm). It was discovered in 1801 by Johann Wilhelm Ritter, who observed that radiation outside the violet end of the visible solar spectrum could decompose silver chloride. Seven decades later, it was discovered that UV light could prevent microbial growth.
  • 2.1K
  • 24 Apr 2022
Topic Review
The Evolution of Fermented Milks
The manufacture of fermented milk products has a long history, and these products were initially produced either from spontaneous fermentation or using a batch of previously produced product, that is, back-slopping. Milk of different mammal species has traditionally been used for the manufacture of fermented milk products. Cow’s milk is the basis for most dairy fermented products around the world. Milk from other mammals, including sheep, goat, camel, mare, buffalo, and yak may have been historically more important and remain so in certain regions. The milks from different species have differences in chemical composition and in certain, vital for the fermentation, components. The diversity of fermented milk products is further influenced by the wide variety of manufacturing practices. A great number of fermented dairy products have been traditionally produced worldwide, and many of them are still produced either following the same traditional process or manufactured industrially, using standardized processes under controlled conditions with specified starter cultures.
  • 2.1K
  • 05 Dec 2022
Topic Review
Glyphosate(N-(phosphonomethyl)glycine)
Glyphosate (N-(phosphonomethyl)glycine) was developed in the early 1970s and at present is used as a herbicide to kill broadleaf weeds and grass. The widely occurring degradation product aminomethylphosphonic acid (AMPA) is a result of glyphosate and amino-polyphosphonate degradation. The massive use of the parent compound leads to the ubiquity of AMPA in the environment, and particularly in water. 
  • 2.1K
  • 26 Oct 2021
Topic Review
List of Intel Itanium Microprocessors
The Itanium from Intel is a high-end server and supercomputer microprocessor.
  • 2.1K
  • 28 Oct 2022
  • Page
  • of
  • 2799
Featured Entry Collections
>>

Featured Reprints

>>
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Encyclopedia of Engineering
Encyclopedia of Social Sciences
Encyclopedia of Medieval Royal Iconography
Academic Video Service
Feedback