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Topic Review
Power (Social)
Power, in a social context, refers to the ability of an individual, group, or institution to influence or control the behavior, decisions, and actions of others. It often manifests in various forms, including political, economic, and social power, and is a dynamic force that shapes relationships and structures within societies. The possession of power grants the capacity to enforce one's will, make decisions, and shape the course of events, playing a central role in the dynamics of governance, social interactions, and institutional structures.
  • 1.9K
  • 25 Jan 2024
Topic Review
Poultry Litter
Poultry litter is a combination of aviary excreta and bedding materials such as wood shavings, sawdust, peanut hulls, shredded sugar cane, straw, or other dry, absorbent, uneaten feed, broken eggs, dead birds, bird feathers and low-cost organic material [1].
  • 1.9K
  • 27 Dec 2020
Topic Review
Natural Photosensitizers in Photodynamic Therapy
Photodynamic therapy (PDT) is a therapy for the treatment of many diseases, including cancer. This therapy uses a combination of a photosensitizer (PS), light irradiation of appropriate length and molecular oxygen. The photodynamic effect kills cancer cells through apoptosis, necrosis, or autophagy of tumor cells.
  • 1.9K
  • 29 Mar 2022
Topic Review
Zirconium and Titanium Phosphates
Zirconium and titanium phosphates are a group of laminar tetravalent metal phosphates that have attracted intensive investigation interests. Unlike zirconium phosphates, titanium phosphates can be also synthesized in another morphology, exhibiting the form of nanorods, and thus are known as nanofibrous titanium phosphates.  The different synthetic routes of zirconium and titanium phosphates and their current and prospective applications with a special mention to the their plausible applications in the field of biotechnology are discussed. 
  • 1.9K
  • 25 Mar 2022
Topic Review
Operad Theory
Operad theory is a field of mathematics concerned with prototypical algebras that model properties such as commutativity or anticommutativity as well as various amounts of associativity. Operads generalize the various associativity properties already observed in algebras and coalgebras such as Lie algebras or Poisson algebras by modeling computational trees within the algebra. Algebras are to operads as group representations are to groups. An operad can be seen as a set of operations, each one having a fixed finite number of inputs (arguments) and one output, which can be composed one with others. They form a category-theoretic analog of universal algebra. Operads originate in algebraic topology from the study of iterated loop spaces by J. Michael Boardman and Rainer M. Vogt, and J. Peter May. The word "operad" was created by May as a portmanteau of "operations" and "monad" (and also because his mother was an opera singer). Interest in operads was considerably renewed in the early 90s when, based on early insights of Maxim Kontsevich, Victor Ginzburg and Mikhail Kapranov discovered that some duality phenomena in rational homotopy theory could be explained using Koszul duality of operads. Operads have since found many applications, such as in deformation quantization of Poisson manifolds, the Deligne conjecture, or graph homology in the work of Maxim Kontsevich and Thomas Willwacher.
  • 1.9K
  • 09 Oct 2022
Topic Review
Similarity
In philosophy, similarity or resemblance is a relation between objects that constitutes how much these objects are alike. Similarity comes in degrees: e.g. oranges are more similar to apples than to the moon. It is traditionally seen as an internal relation and analyzed in terms of shared properties: two things are similar because they have a property in common. The more properties they share, the more similar they are. They resemble each other exactly if they share all their properties. So an orange is similar to the moon because they both share the property of being round, but it is even more similar to an apple because additionally, they both share various other properties, like the property of being a fruit. On a formal level, similarity is usually considered to be a relation that is reflexive (everything resembles itself), symmetric (if a is similar to b then b is similar to a) and non-transitive (a need not resemble c despite a resembling b and b resembling c). Similarity comes in two forms: respective similarity, which is relative to one respect or feature, and overall similarity, which expresses the degree of resemblance between two objects all things considered. There is no general consensus whether similarity is an objective, mind-independent feature of reality, and, if so, whether it is a fundamental feature or reducible to other features. Resemblance is central to human cognition since it provides the basis for the categorization of entities into kinds and for various other cognitive processes like analogical reasoning. Similarity has played a central role in various philosophical theories, e.g. as a solution to the problem of universals through resemblance nominalism or in the analysis of counterfactuals in terms of similarity between possible worlds.
  • 1.9K
  • 03 Nov 2022
Topic Review
Objective Diagnosis for Histopathological Images
Histopathology refers to the examination by a pathologist of biopsy samples. Histopathology images are captured by a microscope to locate, examine, and classify many diseases, such as different cancer types. They provide a detailed view of different types of diseases and their tissue status. These images are an essential resource with which to define biological compositions or analyze cell and tissue structures. This imaging modality is very important for diagnostic applications.The analysis of histopathology images is a prolific and relevant research area supporting disease diagnosis. In this paper, the challenges of histopathology image analysis are evaluated. An extensive review of conventional and deep learning techniques that have been applied in histological image analyses is presented. This entry summarizes many current datasets and highlights important challenges and constraints with recent deep learning techniques, alongside possible future research avenues. Despite the progress made in this research area so far, it is still a significant area of open research because of the variety of imaging techniques and disease-specific characteristics. 
  • 1.9K
  • 29 Jan 2021
Topic Review
Saturn V Instrument Unit
The Saturn V Instrument Unit is a ring-shaped structure fitted to the top of the Saturn V rocket's third stage (S-IVB) and the Saturn IB's second stage (also an S-IVB). It was immediately below the SLA (Spacecraft/Lunar Module Adapter) panels that contained the Lunar Module. The Instrument Unit contains the guidance system for the Saturn V rocket. Some of the electronics contained within the Instrument Unit are a digital computer, analog flight control computer, emergency detection system, inertial guidance platform, control accelerometers and control rate gyros. The instrument unit (IU) for Saturn V was designed by NASA at Marshall Space Flight Center (MSFC) and was developed from the Saturn I IU. NASA's contractor to construct the Saturn V Instrument Unit was International Business Machines (IBM). One of the unused Instrument Units is currently on display at the Steven F. Udvar-Hazy Center in Chantilly, Virginia. The plaque for the Unit has the following inscription: The Saturn V rocket, which sent astronauts to the Moon, used inertial guidance, a self-contained system that guided the rocket's trajectory. The rocket booster had a guidance system separate from those on the command and lunar modules. It was contained in an instrument unit like this one, a ring located between the rocket's third stage and the command and lunar modules. The ring contained the basic guidance system components—a stable platform, accelerometers, a digital computer, and control electronics—as well as radar, telemetry, and other units. The instrument unit's stable platform was based on an experimental unit for the German V-2 rocket of World War II. The Bendix Corporation produced the platform, while IBM designed and built the unit's digital computer.
  • 1.9K
  • 06 Dec 2022
Topic Review
AI for Addressing Algorithmic Bias in Job Hiring
More businesses are using artificial intelligence (AI) in curriculum vitae (CV) screening. While the move improves efficiency in the recruitment process, it is vulnerable to biases, which have adverse effects on organizations and the broader society. It recommends the need for collaboration between machines and humans to enhance the fairness of the hiring process. The results can help AI developers make algorithmic changes needed to enhance fairness in AI-driven tools. This will enable the development of ethical hiring tools, contributing to fairness in society.
  • 1.9K
  • 20 Feb 2024
Topic Review
Microneedle-mediated protein delivery
Microneedle (MN) patches, consisting of micro/miniature-sized needles, are a promising tool to perforate the stratum corneum and to release drugs and proteins into the dermis following a non-invasive route. 
  • 1.9K
  • 28 Oct 2020
Topic Review
Tocotrienols: Stroke and Myocardial Infarction
Although the current treatments for stroke and myocardial infarction contribute to an improvement in mortality rates, the consequences of reperfusion therapy have remained a challenge. Tocotrienols have been shown to exert beneficial effects on the brain and heart.  We retrieved articles from Scopus, MEDLINE and PubMed from inception to June 2021, and included any studies using tocotrienols as a treatment for cerebral or myocardial I/R injury therapy. Observational studies and review articles were excluded, and the risk of bias was conducted using a specific tool for animal study (SYRCLE). The data were analyzed qualitatively. Twelve articles met the eligibility criteria. Tocotrienols significantly improved the structural, functional, and biochemical parameters in both cerebral and myocardial I/R injury models. In contrast, oxidative stress, inflammation, and apoptosis were markedly attenuated by tocotrienol treatment. Limitations to the analysis included marked differences in animal models, disease inductions, forms of tocotrienols, and an unclear risk of bias in certain types of bias. However, tocotrienols have the potential to serve as a supplement for reducing the impact of reperfusion injury. 
  • 1.9K
  • 10 Sep 2021
Topic Review
High Performance Polymer Composites
Summarize data on the structure, mechanical and tribological properties, and wear patterns of composites based on high-performance polymers (HPPs) intended for use in friction units. The three key sections, divided according to the tribological contact schemes regardless of the polymer matrix. In the second part, the analysis of composites is carried out in point contacts. The third section is devoted to the results of studies of HPP-based composites in linear ones. The fourth section summarizes information on flat contacts. Particular attention is paid to the formation of transfer films (TFs) in the contacts and their influence on the tribological patterns of the studied rubbing materials.
  • 1.9K
  • 16 Mar 2022
Topic Review
Salt Stress in Plants
Salinization of soils and freshwater resources by natural processes and/or human activities has become an increasing issue that affects environmental services and socioeconomic relations. In addition, salinization jeopardizes agroecosystems, inducing salt stress in most cultivated plants (nutrient deficiency, pH and oxidative stress, biomass reduction), and directly affects the quality and quantity of food production. Depending on the type of salt/stress (alkaline or pH-neutral), specific approaches and solutions should be applied to ameliorate the situation on-site.
  • 1.9K
  • 23 Mar 2022
Topic Review
Comparison of On-demand Music Streaming Services
The following is a list of on-demand music streaming services. The services offer streaming of full-length content via the Internet as a part of their service, without the listener necessarily purchasing a file for download. This type of service is comparable to Internet radio. Many of these sites have advertising and offer non-free options in the style of an online music store. For a list of online music stores that provide a means of purchasing and downloading music as files of some sort, see: Comparison of online music stores. Many of both types of sites offer services similar to an online music database.
  • 1.9K
  • 17 Oct 2022
Topic Review
Training, Validation, and Test Sets
In machine learning, a common task is the study and construction of algorithms that can learn from and make predictions on data. Such algorithms function by making data-driven predictions or decisions, through building a mathematical model from input data. These input data used to build the model are usually divided in multiple data sets. In particular, three data sets are commonly used in different stages of the creation of the model: training, validation and test sets. The model is initially fit on a training data set, which is a set of examples used to fit the parameters (e.g. weights of connections between neurons in artificial neural networks) of the model. The model (e.g. a naive Bayes classifier) is trained on the training data set using a supervised learning method, for example using optimization methods such as gradient descent or stochastic gradient descent. In practice, the training data set often consists of pairs of an input vector (or scalar) and the corresponding output vector (or scalar), where the answer key is commonly denoted as the target (or label). The current model is run with the training data set and produces a result, which is then compared with the target, for each input vector in the training data set. Based on the result of the comparison and the specific learning algorithm being used, the parameters of the model are adjusted. The model fitting can include both variable selection and parameter estimation. Successively, the fitted model is used to predict the responses for the observations in a second data set called the validation data set. The validation data set provides an unbiased evaluation of a model fit on the training data set while tuning the model's hyperparameters (e.g. the number of hidden units—layers and layer widths—in a neural network). Validation datasets can be used for regularization by early stopping (stopping training when the error on the validation data set increases, as this is a sign of over-fitting to the training data set). This simple procedure is complicated in practice by the fact that the validation dataset's error may fluctuate during training, producing multiple local minima. This complication has led to the creation of many ad-hoc rules for deciding when over-fitting has truly begun. Finally, the test data set is a data set used to provide an unbiased evaluation of a final model fit on the training data set. If the data in the test data set has never been used in training (for example in cross-validation), the test data set is also called a holdout data set. The term "validation set" is sometimes used instead of "test set" in some literature (e.g., if the original data set was partitioned into only two subsets, the test set might be referred to as the validation set). Deciding the sizes and strategies for data set division in training, test and validation sets is very dependent on the problem and data available.
  • 1.9K
  • 17 Oct 2022
Topic Review
Food Loss and Waste
According to the Food and Agriculture Organization (FAO), about 1.3 billion tons of food, equivalent to one-third of worldwide food production, is lost or wasted. Along the value chain, food loss and waste (FLW) occur at every stage, including production, transportation, storage, processing, retailing, and consumption. Compared to developing countries, very few post-harvest losses occur in developed countries due to technical progress. However, in developing countries, about 40% of the total FLW comes from households.
  • 1.9K
  • 28 Nov 2022
Biography
Oskar Negt
Oskar Reinhard Negt (German pronunciation: [ˈneːkt]; born 1 August 1934 in Kapkeim, East Prussia) is a philosopher and critical social theorist. He is an emeritus professor of sociology at Leibniz University Hannover, and one of Germany's most prominent social scientists.[1][2] Little of his work has been translated into English. Negt studied law and philosophy in the University of Göttingen
  • 1.9K
  • 09 Dec 2022
Topic Review
Biomedical Applications of Magnesium Oxide Nanoparticles
Magnesium oxide (MgO) nanoparticles have excellent biocompatibility, stability, and diverse biomedical uses, such as antimicrobial, antioxidant, anticancer, and antidiabetic properties, as well as tissue engineering, bioimaging, and drug delivery applications. Magnesium oxide nanoparticles demonstrate substantial biocompatibility and display significant antibacterial, antifungal, anticancer, and antioxidant properties.
  • 1.9K
  • 28 Feb 2024
Topic Review
Oxidative Stress in NAFLD
Oxidative stress is defined as an imbalance between the cellular levels of antioxidants and that of pro-oxidants, including ROS and reactive nitrogen species, which causes cellular damage and, in most cases, cell death. Non-alcoholic fatty liver disease (NAFLD) is often the hepatic expression of metabolic syndrome and its comorbidities that comprise, among others, obesity and insulin-resistance. At the molecular level, several models have been proposed for the pathogenesis of NAFLD. Most importantly, oxidative stress and mitochondrialdamage have been reported to be causative in NAFLD initiation and progression.
  • 1.9K
  • 02 Aug 2021
Topic Review
The Double-Tube Heat Exchanger Performance
The double-tube heat exchanger is one of the most common designs of heat exchangers used in commercial and industrial applications. It is the simplest and one in which hot and cold fluids move in same or opposite directions. Various methods are presented to improve a double-tube heat exchanger.  
  • 1.9K
  • 26 Oct 2022
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