Institution
Simón Bolívar University
Education•Caracas, Venezuela•
About: Simón Bolívar University is a education organization based out in Caracas, Venezuela. It is known for research contribution in the topics: Population & Crystallization. The organization has 5912 authors who have published 8294 publications receiving 126152 citations.
Topics: Population, Crystallization, Context (language use), Nucleation, Differential scanning calorimetry
Papers published on a yearly basis
Papers
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TL;DR: In this paper, the pigment distributions of a variety of lake and marine sediments from different depositional settings reveal the presence of steryl chlorin esters as significant components of the chlorin assemblages.
50 citations
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TL;DR: This paper introduces a novel method for automatic classification of normal and abnormal heart sound recordings using a nested set of ensemble algorithms and helps reduce overfitting and improved classification performance.
Abstract: Objective: Heart sound classification and analysis play an important role in the early diagnosis and prevention of cardiovascular disease. To this end, this paper introduces a novel method for automatic classification of normal and abnormal heart sound recordings. Approach: Signals are first preprocessed to extract a total of 131 features in the time, frequency, wavelet and statistical domains from the entire signal and from the timings of the states. Outlier signals are then detected and separated from those with a standard range using an interquartile range algorithm. After that, feature extreme values are given special consideration, and finally features are reduced to the most significant ones using a feature reduction technique. In the classification stage, the selected features either for standard or outlier signals are fed separately into an ensemble of 20 two-step classifiers for the classification task. The first step of the classifier is represented by a nested set of ensemble algorithms which was cross-validated on the training dataset provided by PhysioNet Challenge 2016, while the second one uses a voting rule of the class label. Main results: The results show that this method is able to recognize heart sound recordings efficiently, achieving an overall score of 96.30% for standard signals and 90.18% for outlier signals on a cross-validated experiment using the available training data. Significance: The approach of our proposed method helped reduce overfitting and improved classification performance, achieving an overall score on the hidden test set of 80.1% (79.6% sensitivity and 80.6% specificity).
49 citations
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TL;DR: The most active compound to emerge from the in vitro and in vivo murine studies was 2b, suggesting an antimalarial activity via inhibition of hemoglobin hydrolysis, however, not as efficient as chloroquine.
49 citations
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TL;DR: In this article, a method to locate phase coexistence points using molecular dynamics (MD) simulations is presented. But the method is limited to single component and binary Lennard-Jones (LJ) fluids and cannot be used to locate vapor-liquid, liquid-liquid or solid-fluid equilibria.
49 citations
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TL;DR: In this paper, the authors applied different techniques to amorphous and semicrystalline bisphenol-A polycarbonate with crystallinity degrees up to 21.8%, in a temperature interval covering the α and β relaxations.
Abstract: Thermally Stimulated Depolarization Current technique, Differential Scanning Calorimetry, and Dynamic Mechanical Analysis have been applied to amorphous and semicrystalline bisphenol-A polycarbonate with crystallinity degrees up to 21.8%, in a temperature interval covering the α and β relaxations. The secondary β transition is found to be the sum of three components whose variations in aged and annealed specimens have shown the cooperative character of the β1 and β2 modes, contrary to the localized nature of the β3 component. A Tg decrease was observed by both TSDC and DSC as a function of Xc and has been related to the possible confinement of the mobile amorphous phase in regions whose sizes are smaller than the correlation lengths of the cooperative movements that characterize the motions occurring at Tg. The α relaxation intensity variations with crystallinity show the existence of an abundant rigid amorphous phase in the semicrystalline material. The relaxation parameters deduced from the Direct Signal Analysis of the α relaxation for the mobile amorphous phase do not show significant deviations from those found for the amorphous material. The existence of the rigid amorphous phase has been associated to the ductile-to-brittle transition experienced by the material at low crystallinity levels. © 1996 John Wiley & Sons, Inc.
49 citations
Authors
Showing all 5925 results
Name | H-index | Papers | Citations |
---|---|---|---|
Franco Nori | 114 | 1117 | 63808 |
Ignacio Rodriguez-Iturbe | 96 | 334 | 32283 |
Ian W. Hamley | 78 | 469 | 25800 |
Francisco Zaera | 73 | 432 | 19907 |
Thomas G. Habetler | 73 | 395 | 20725 |
Douglas L. Jones | 70 | 512 | 21596 |
I. Taboada | 66 | 346 | 13528 |
Enrique Herrero | 64 | 242 | 11653 |
Rudi Studer | 60 | 268 | 19876 |
Alejandro J. Müller | 58 | 420 | 12410 |
David Padua | 58 | 243 | 11155 |
Rudolf Jaffé | 58 | 182 | 10268 |
Luis Balicas | 57 | 328 | 14114 |
Volker Abetz | 55 | 386 | 11583 |
Ananias A. Escalante | 51 | 160 | 8866 |