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Topic Review
Pliosaurus
Pliosaurus (meaning 'more lizard') is an extinct genus of thalassophonean pliosaurid known from the Kimmeridgian and Tithonian stages (Late Jurassic) of Europe and South America. Their diet would have included fish, cephalopods, and marine reptiles. This genus has contained many species in the past but recent reviews found only six (P. brachydeirus, P. carpenteri, P. funkei, P. kevani, P. rossicus and P. westburyensis) to be valid, while the validity of two additional species awaits a petition to the International Code of Zoological Nomenclature. Currently, P. brachyspondylus and P. macromerus are considered dubious, while P. portentificus is considered undiagnostic. Most species of Pliosaurus reached 8 metres (26 ft) in length and 5 metric tons (5.5 short tons) in body mass, while P. rossicus and P. funkei may have reached or even exceeded 10 metres (33 ft) in length and 11 metric tons (12 short tons) in body mass, being the largest plesiosaurs of all time. Species of this genus are differentiated from other pliosaurids based on seven autapomorphies, including teeth that are triangular in cross section.
  • 2.1K
  • 16 Nov 2022
Topic Review
TPT
TPT (time partition testing) is a systematic test methodology for the automated software test and verification of embedded control systems, cyber-physical systems, and dataflow programs. TPT is specialised on testing and validation of embedded systems whose inputs and outputs can be represented as signals and is a dedicated method for testing continuous behaviour of systems. Most control systems belong to this system class. The outstanding characteristic of control systems is the fact that they interact closely interlinked with a real world environment. Controllers need to observe their environment and react correspondingly to its behaviour. The system works in an interactional cycle with its environment and is subject to temporal constraints. Testing these systems is to stimulate and to check the timing behaviour. Traditional functional testing methods use scripts – TPT uses model-based testing. TPT combines a systematic and graphic modelling technique for test cases with a fully automated test execution in different environments and automatic test evaluation. TPT covers the following four test activities:
  • 2.1K
  • 08 Oct 2022
Topic Review
Cervical Epithelial Cells
Using Raman microscopy, we investigated epithelial cervical cells collected from 96 women with squamous cell carcinoma (SCC) or belonging to groups I, IIa, IIID-1 and IIID-2 according to Munich III classification (IIID-1 and IIID-2 corresponding to Bethesda LSIL and HSIL groups, respectively). All women were tested for human papillomavirus (HPV) infection using PCR. Subcellular resolution of Raman microscopy enabled to understand phenotypic differences in a heterogeneous population of cervical cells in the following groups: I/HPV−, IIa/HPV−, IIa/HPV−, LSIL/HPV−, LSIL/HPV+, HSIL/HPV−, HSIL/HPV+ and cancer cells (SCC/HPV+). We showed for the first time that the glycogen content in the cytoplasm decreased with the nucleus size of cervical cells in all studied groups apart from the cancer group. For the subpopulation of large-nucleus cells HPV infection resulted in considerable glycogen depletion compared to HPV negative cells in IIa, LSIL (for both statistical significance, ca. 45%) and HSIL (trend, 37%) groups. We hypothesize that accelerated glycogenolysis in large-nucleus cells may be associated with the increased protein metabolism for HPV positive cells. Our work underlines unique capabilities of Raman microscopy in single cell studies and demonstrate potential of Raman-based methods in HPV diagnostics.
  • 2.1K
  • 29 Oct 2020
Topic Review
Brewer’s Spent Grains
Brewer’s spent grains (BSG) is the main solid by-product in the brewing industry, obtained during lautering. BSG has a multitude of applications and it can be used as a valuable fedstock for production of different products. Moreover, it could also be used as a biomass for energy purposes.
  • 2.1K
  • 21 Dec 2020
Topic Review
Formic Acid for Hydrogen Production
Formic acid is a liquid organic hydrogen carrier giving hydrogen on demand using catalysts. Metal complexes are known to be used as efficient catalysts for the hydrogen production from formic acid decomposition. Their performance could be better than those of supported catalysts with metal nanoparticles. However, difficulties to separate metal complexes from the reaction mixture limit their industrial applications. This problem can be resolved by supporting metal complexes on the surface of different supports, which may additionally provide some surface sites for the formic acid activation.
  • 2.1K
  • 30 Mar 2021
Topic Review
Crystallization Behavior and Quality of Frozen Meat
Preservation of meat through freezing entails the use of low temperatures to extend a product’s shelf-life, mainly by reducing the rate of microbial spoilage and deterioration reactions. Characteristics of meat that are important to be preserve include tenderness, water holding capacity, color, and flavor. In general, freezing improves meat tenderness, but negatively impacts other quality attributes. The extent to which these attributes are affected depends on the ice crystalline size and distribution, which itself is governed by freezing rate and storage temperature and duration.
  • 2.1K
  • 18 Nov 2021
Topic Review
Variables Impact Healthcare Outcome Measures and Data Management
The rapid growth of technology, digitalization of health records, and unprecedented data management of healthcare information enable healthcare providers and researchers to assist in healthcare quality improvement and community health outcomes. Data management and potential variables affect the performance of healthcare measures. Data analytics enables healthcare providers and researchers to evaluate, monitor performance, and track healthcare quality across the continuum of patient care. The data type is an attribute of data that tells the aggregator or interpreter how the programmer intends to use the data.
  • 2.1K
  • 05 Jul 2022
Topic Review
2019 in Politics and Government
Events pertaining to world affairs in 2019, national politics, public policy, government, world economics, and international business, that took place in various nations, regions, organizations, around the world in 2019.
  • 2.1K
  • 08 Nov 2022
Topic Review Video Peer Reviewed
Lorenz’s View on the Predictability Limit of the Atmosphere
To determine whether (or not) the intrinsic predictability limit of the atmosphere is two weeks and whether (or not) Lorenz’s approaches support this limit, this entry discusses the following topics: (A). The Lorenz 1963 model qualitatively revealed the essence of a finite predictability within a chaotic system such as the atmosphere. However, the Lorenz 1963 model did not determine a precise limit for atmospheric predictability. (B). In the 1960s, using real-world models, the two-week predictability limit was originally estimated based on a doubling time of five days. The finding was documented by Charney et al. in 1966 and has become a consensus. Throughout this entry, Major Point A and B are used as respective references for these topics. A literature review and an analysis suggested that the Lorenz 1963 model qualitatively revealed a finite predictability, and that findings of the Lorenz 1969 model with a saturation assumption supported the idea of the two-week predictability limit, which, in the 1960s, was estimated based on a doubling time of five days obtained using real-world models. However, the theoretical Lorenz 1963 and 1969 models have limitations, such as a lack of certain processes and assumptions, and, therefore, cannot represent an intrinsic predictability limit of the atmosphere. This entry suggests an optimistic view for searching for a predictability limit using different approaches and is supported by recent promising simulations that go beyond two weeks.
  • 2.1K
  • 07 Aug 2023
Topic Review
Mechanisms of Phase Variation
Bacteria live in environments that are in constant flux, and therefore have developed numerous methods to adapt to their ever-changing surroundings. One of these methods of adaptation is called Phase Variation (PV) which is a mechanism of -high-frequency reversible gene expression switching that enables bacteria to generate heterogeneity to successfully compete in uncertain conditions. This entry details the mechanisms of PV and takes a look at them in the context of examples from different bacterial species, with a focus on S. aureus. 
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  • 02 Mar 2021
Topic Review
Property of Phytosterols
Phytosterols are functional ingredients with known efficacy and safety. Phytosterols are found as free sterols or as their esters with fatty acids. Although phytosterol esters are soluble in oil and have been used in many commercial foods, it has been difficult to similarly use free phytosterols since they are insoluble in water and practically insoluble in oil. Phytosterols are attractive, functional ingredients for preventing arteriosclerotic diseases since they reduce serum total cholesterol and LDL-cholesterol levels.
  • 2.1K
  • 12 Aug 2022
Topic Review
Solid Phase Extraction
Solid-phase extraction (SPE) is an extractive technique by which compounds that are dissolved or suspended in a liquid mixture are separated from other compounds in the mixture according to their physical and chemical properties. Analytical laboratories use solid phase extraction to concentrate and purify samples for analysis. Solid phase extraction can be used to isolate analytes of interest from a wide variety of matrices, including urine, blood, water, beverages, soil, and animal tissue. SPE uses the affinity of solutes dissolved or suspended in a liquid (known as the mobile phase) for a solid through which the sample is passed (known as the stationary phase) to separate a mixture into desired and undesired components. The result is that either the desired analytes of interest or undesired impurities in the sample are retained on the stationary phase. The portion that passes through the stationary phase is collected or discarded, depending on whether it contains the desired analytes or undesired impurities. If the portion retained on the stationary phase includes the desired analytes, they can then be removed from the stationary phase for collection in an additional step, in which the stationary phase is rinsed with an appropriate eluent. Many of the adsorbents/materials are the same as in chromatographic methods, but SPE is distinctive, with aims separate from chromatography, and so has a unique niche in modern chemical science.
  • 2.1K
  • 29 Sep 2022
Topic Review
Tranexamic Acid in Melasma and Sun-Induced Hyperpigmentation Treatment
Tranexamic acid (TXA) has anti-plasmin activity and has been shown when administered orally to be effective against melasma, for which it is considered first-line pharmacotherapy. Several studies have shown that topically applied TXA is also effective against melasma and skin hyperpigmentation caused by sunburn and inflammation. The TXA concentration in the epidermis and dermis/vasculature has been estimated from its distribution in the skin after closed application, and topically applied TXA has thus been shown to act on neutrophils and mast cells in the dermis and on the vascular system.
  • 2.1K
  • 04 Nov 2022
Topic Review
Linguistic Insecurity
Linguistic insecurity comprises feelings of anxiety, self-consciousness, or lack of confidence in the mind of a speaker surrounding the use of their own language. Often, this anxiety comes from speakers' belief that their use of language does not conform to the perceived standard and/or the style of language expected by the speakers' interlocutor(s). Linguistic insecurity is situationally induced and is often based on a feeling of inadequacy regarding personal performance in certain contexts, rather than a fixed attribute of an individual. This insecurity can lead to stylistic, and phonetic shifts away from an affected speaker's default speech variety; these shifts may be performed consciously on the part of the speaker, or may be reflective of an unconscious effort to conform to a more prestigious or context-appropriate style of speech. Linguistic insecurity is linked to the perception of speech styles in any community, and so may vary based on socioeconomic class and gender. It is also especially pertinent in multilingual societies.
  • 2.1K
  • 16 Nov 2022
Topic Review
Carbon Quantum Dots
Carbon dots have gained tremendous interest attributable to their unique features. Two approaches are involved in the fabrication of quantum dots (Top-down and Bottom-up). Most of the synthesis methods are usually multistep, required harsh conditions, and costly carbon sources that may have a toxic effect, therefore green synthesis is more preferable. Herein, the current review presents the green synthesis of carbon quantum dots (CQDs) and graphene quantum dots 
  • 2.1K
  • 06 Apr 2021
Topic Review
Fungi in the Cocoa Production
The role of fungi in cocoa crops is mainly associated with plant diseases and contamination of harvest with unwanted metabolites such as mycotoxins that can reach the final consumer. However, they can be play a positive role as endophytic promoting plant protection and growth; in addition they could play an important role in the fermentation step providing extracellular enzymes important to the pulp bean degradation. 
  • 2.1K
  • 10 May 2021
Topic Review
High Pressure Processing for Gelatinization and Nutrients Infusion
High pressure processing (HPP) is a novel technology that involves subjecting foods to high hydrostatic pressures of the order of 100–600 MPa. This technology has been proven successful for inactivation of numerous microorganisms, spores and enzymes in foods, leading to increased shelf life. HPP is not limited to cold pasteurization but has many other applications. The focus of this entry is to explore other applications of HPP, such as gelatinization, forced water absorption and infusion of nutrients. The use of high pressure in producing cold gelatinizing effects, imparting unique properties to food and improving food quality has also been discussed, highlighting the latest published studies and the innovative methods adopted.
  • 2.1K
  • 30 Nov 2021
Topic Review
Zeolites as Carriers of Nano-Fertilizers
The world is facing immense challenges in terms of food security, due to the combined impacts of the ever-increasing population and the adversity of climate change. In an attempt to counteract these factors, smart nutrient delivery systems, including nano-fertilizers, additives, and material coatings, have been introduced to increase food productivity to meet the growing food demand. Use of nanocarriers in agro-practices for sustainable farming contributes to achieving up to 75% nutrient delivery for a prolonged period to maintain nutrient availability in soil for plants in adverse soil conditions.
  • 2.1K
  • 29 Sep 2022
Topic Review
Joint Space Operations Center
The Combined Space Operations Center (CSpOC) (formerly the Joint Space Operations Center (JSpOC)) is a command and control (C2) weapon system focused on planning and executing US Strategic Command's Joint Functional Component Command for Space (JFCC SPACE) mission. The purpose of the CSpOC is to provide a focal point for the operational employment of worldwide joint space forces, and enable the Commander of JFCC SPACE (CDR JFCC SPACE) to integrate space power into global military operations. The CSpOC is located at Vandenberg Air Force Base in California, and is the organization responsible for performing all of the orbit determination activity necessary to maintain the US space catalogue.
  • 2.1K
  • 09 Oct 2022
Topic Review
Refugee Children
Nearly half of all refugees are children, and almost one in three children living outside their country of birth is a refugee. These numbers encompass children whose refugee status has been formally confirmed, as well as children in refugee-like situations. In addition to facing the direct threat of violence resulting from conflict, forcibly displaced children also face various health risks, including: disease outbreaks and long-term psychological trauma, inadequate access to water and sanitation, nutritious food, and regular vaccination schedules. Refugee children, particularly those without documentation and those who travel alone, are also vulnerable to abuse and exploitation. Although many communities around the world have welcomed them, forcibly displaced children and their families often face discrimination, poverty, and social marginalization in their home, transit, and destination countries. Language barriers and legal barriers in transit and destination countries often bar refugee children and their families from accessing education, healthcare, social protection, and other services. Many countries of destination also lack intercultural supports and policies for social integration. Such threats to safety and well-being are amplified for refugee children with disabilities.
  • 2.1K
  • 24 Oct 2022
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