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Topic Review
Evolution of Dinosaurs
Dinosaurs evolved within a single lineage of archosaurs 243-233 Ma (million years ago) from the Anisian to the Carnian ages, the latter part of the middle Triassic. Dinosauria is a well-supported clade, present in 98% of bootstraps. It is diagnosed by many features including loss of the postfrontal on the skull and an elongate deltopectoral crest on the humerus. In March 2017, scientists reported a new way of classifying the dinosaur family tree, based on newer and more evidence than available earlier. According to the new classification, the original dinosaurs, arising 200 million years ago, were small, two-footed omnivorous animals with large grasping hands. Descendants (for the non-avian dinosaurs) lasted until 66 million years ago.
  • 3.7K
  • 14 Oct 2022
Topic Review
Curcumin and Peripheral Neuropathies
Peripheral neuropathies (PN) can be triggered after metabolic diseases, traumatic peripheral nerve injury, genetic mutations, toxic substances, and/or inflammation. PN is a major clinical problem, affecting many patients and with few effective therapeutics. Recently, interest in natural dietary compounds, such as polyphenols, in human health has led to a great deal of research, especially in PN. Curcumin is a polyphenol extracted from the root of Curcuma longa. This molecule has long been used in Asian medicine for its anti-inflammatory, antibacterial, and antioxidant properties. However, like numerous polyphenols, curcumin has a very low bioavailability and a very fast metabolism. This part provides an overview of curcumin in the treatment of PN (anti-inflammatory, antioxidant, anti-endoplasmic reticulum stress (anti-ER-stress), neuroprotection, and glial protection). Finally, because PN are associated with numerous pathologies (e.g., cancers, diabetes, addiction, inflammatory disease...), this part is likely to interest a large audience.
  • 3.7K
  • 20 Oct 2020
Topic Review
Persuasive Technology
Persuasive technology is broadly defined as technology that is designed to change attitudes or behaviors of the users through persuasion and social influence, but not necessarily through coercion. Such technologies are regularly used in sales, diplomacy, politics, religion, military training, public health, and management, and may potentially be used in any area of human-human or human-computer interaction. Most self-identified persuasive technology research focuses on interactive, computational technologies, including desktop computers, Internet services, video games, and mobile devices, but this incorporates and builds on the results, theories, and methods of experimental psychology, rhetoric, and human-computer interaction. The design of persuasive technologies can be seen as a particular case of design with intent.
  • 3.7K
  • 28 Sep 2022
Topic Review Peer Reviewed
Domestic Environmental Experience Design
The term 'domestic environmental experience' was defined as users' experiences of cognitive perceptions and physical responses to their domestic built environments. Domestic environments can be enriched through the implementation of environmental experience design (EXD) by combining users' environmental, spatial and contextual factors that may accommodate occupants' needs and demands as well as their health and wellbeing. Here, an EXD theoretical concept has been developed based on the 'User-Centred Design' thematical framework.
  • 3.7K
  • 13 Apr 2022
Topic Review
Laser Powder Bed Fusion
Laser powder bed fusion (LPBF) is the most used metal additive manufacturing technique, and it is based on the efficient interaction between a high-energy laser and a metal powder feedstock. The reuse of the powder feedstock is crucial to make the process cost-efficient and environmentally friendly. However, since studies of the mechanical and microstructural properties of parts produced with reused powders show scattered results, a closer look to the powder, heat source and shielding gas properties and to how they interact during the LPBF process is presented.  
  • 3.7K
  • 29 Oct 2020
Topic Review
Matthews Correlation Coefficient
The Matthews correlation coefficient (MCC) or phi coefficient is used in machine learning as a measure of the quality of binary (two-class) classifications, introduced by biochemist Brian W. Matthews in 1975. The MCC is defined identically to Pearson's phi coefficient, introduced by Karl Pearson, also known as the Yule phi coefficient from its introduction by Udny Yule in 1912. Despite these antecedents which predate Matthews's use by several decades, the term MCC is widely used in the field of bioinformatics and machine learning. The coefficient takes into account true and false positives and negatives and is generally regarded as a balanced measure which can be used even if the classes are of very different sizes. The MCC is in essence a correlation coefficient between the observed and predicted binary classifications; it returns a value between −1 and +1. A coefficient of +1 represents a perfect prediction, 0 no better than random prediction and −1 indicates total disagreement between prediction and observation. However, if MCC equals neither −1, 0, or +1, it is not a reliable indicator of how similar a predictor is to random guessing because MCC is dependent on the dataset. MCC is closely related to the chi-square statistic for a 2×2 contingency table where n is the total number of observations. While there is no perfect way of describing the confusion matrix of true and false positives and negatives by a single number, the Matthews correlation coefficient is generally regarded as being one of the best such measures. Other measures, such as the proportion of correct predictions (also termed accuracy), are not useful when the two classes are of very different sizes. For example, assigning every object to the larger set achieves a high proportion of correct predictions, but is not generally a useful classification. The MCC can be calculated directly from the confusion matrix using the formula: In this equation, TP is the number of true positives, TN the number of true negatives, FP the number of false positives and FN the number of false negatives. If any of the four sums in the denominator is zero, the denominator can be arbitrarily set to one; this results in a Matthews correlation coefficient of zero, which can be shown to be the correct limiting value. The MCC can be calculated with the formula: using the positive predictive value, the true positive rate, the true negative rate, the negative predictive value, the false discovery rate, the false negative rate, the false positive rate, and the false omission rate. The original formula as given by Matthews was: This is equal to the formula given above. As a correlation coefficient, the Matthews correlation coefficient is the geometric mean of the regression coefficients of the problem and its dual. The component regression coefficients of the Matthews correlation coefficient are Markedness (Δp) and Youden's J statistic (Informedness or Δp'). Markedness and Informedness correspond to different directions of information flow and generalize Youden's J statistic, the [math]\displaystyle{ \delta }[/math]p statistics and (as their geometric mean) the Matthews Correlation Coefficient to more than two classes. Some scientists claim the Matthews correlation coefficient to be the most informative single score to establish the quality of a binary classifier prediction in a confusion matrix context.
  • 3.7K
  • 18 Nov 2022
Topic Review
Medium-Voltage Switchgear Condition Monitoring
Switchgear are a key component of the electrical grid. They serve both protective and control roles in distribution electric power with in the grid. It is therefore important to monitor and predict the condition of these assets. Thereby, condition monitoring is divided into three main tasks: breaker drive monitoring, thermal monitoring and partial discharge monitoring. This encyclopedia article provides an overview of the potential failure modes and monitoring techniques. More details can be found in an exhaustive review article, cited below.
  • 3.7K
  • 29 Oct 2020
Topic Review
Nanodiamonds Synthesis Techniques
The "state-of-the-art" of the nanodiamonds synthesis techniques is reviewed with emphasis on the more recent one involving pulsed laser ablation. Production of NV centers inside the nanodiamonds and  post-production cleaning processes to remove residual graphite layers are also described.
  • 3.7K
  • 27 Oct 2020
Topic Review Peer Reviewed
Microchip Electrophoresis
Microchip electrophoresis (MCE) is a miniaturized form of capillary electrophoresis. Electrophoresis is a common technique to separate macromolecules such as nucleic acids (DNA, RNA) and proteins. This technique has become a routine method for DNA size fragmenting and separating protein mixtures in most laboratories around the world. The application of higher voltages in MCE achieves faster and efficient electrophoretic separations. 
  • 3.7K
  • 13 Apr 2022
Topic Review
Empire of Liberty
The Empire of Liberty is a theme developed first by Thomas Jefferson to identify the responsibility of the United States to spread freedom across the world. Jefferson saw the mission of the U.S. in terms of setting an example, expansion into western North America, and by intervention abroad. Major exponents of the theme have been James Monroe (and his Monroe Doctrine), Andrew Jackson and James K. Polk (who promoted Manifest Destiny), Abraham Lincoln (in the Gettysburg Address), Theodore Roosevelt, Woodrow Wilson (and "Wilsonianism"), Franklin D. Roosevelt, Harry Truman, Ronald Reagan, Bill Clinton, and George W. Bush. In the history of U.S. foreign policy, the Empire of Liberty has provided motivation to fight the Spanish–American War (1898), World War I (1917-18), the later part of World War II (1941-45), the Cold War (1947–91) and the War on Terror (2001–present).
  • 3.7K
  • 26 Oct 2022
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