A simple stochastic approach, designed to model the movement of electrons throughout chemical bonds, is introduced. This model makes use of a Markov matrix to codify useful structural information in QSAR. The self-return probabilities of this matrix throughout time ((SR)pi(k)) are then used as molecular descriptors. Firstly, a calculation of (SR)pi(k) is made for a large series of anticancer and non-anticancer chemicals. Then, k-Means Cluster Analysis allows us to split the data series into clusters and ensure a representative design of training and predicting series. Next, we develop a classification function through Linear Discriminant Analysis (LDA). This QSAR discriminates between anticancer compounds and non-active compounds with a correct global classification of 90.5% in the training series. The model also correctly classified 86.07% of the compounds in the predicting series. This classification function is then used to perform a virtual screening of a combinatorial library of coumarins. In this connection, the biological assay of some furocoumarins, selected by virtual screening using the present model, gives good results. In particular, a tetracyclic derivative of 5-methoxypsoralen (5-MOP) has an IC50 against HL-60 tumoral line around 6 to 10 times lower than those for 8-MOP and 5-MOP (reference drugs), respectively. Finally, application of Iso-contribution Zone Analysis (IZA) provides structural interpretation of the biological activity predicted with this QSAR.
This paper motivates and describes the data integration component of INDUS (Intelligent DataUndersianding System) environment for data-driven information extraction and integration from heterogeneous, distributed, autonomous information sources. The design of INDUS is motivated by the reqtrirements of applications such as scient@ discoveiy, in which it is desirable for users to be able to access, flexibly interpret, and analyze data from diverse sources from different perspectives in different contexts. INDUS implements a federated, querycentric approach to data integration using user-specified ontologies.
The recent development of the Colombian legislation, have been identified the need to develop protective clothing to work according to specifications from the work done and in compliance with international standards. These involve the development and design of new strategies and measures for work clothing design. In this study we analyzes the activities of the workers in the electrical sector, the method analyzes the risks activity data in various activities, that activities include power generation plants, local facilities, industrial facilities and maintenance of urban and rural networks. The analyses method is focused on ergonomic approach, risk analysis is done, we evaluate the role of security expert and we use a design algorithm developed for this purpose. The result of this study is the identification of constraints and variables that contribute to the development of a model of analysis that leads to the development the work protective clothes.
Background and hypothesis:The purpose of this study was the comprehensive evaluation of the changes in pulmonary venous and mitral flow velocities of patients with acute and chronic severe aortic regurgitation. Transmitral flow velocities obtained with pulsed-wave Doppler echocardiography have been used to provide information on left ventricular (LV) filling and diastolic function. Pulmonary venous flow tracings are an important adjunct to LV inflow pattern in assessing LV diastolic function.Methods; Fourteen patients with severe aortic regurgitation (8 chronic and 6 acute) and in sinus rhythm were examined by transthoracic and transesophageal pulsed Doppler echocardiography. Mitral and pulmonary flow velocities were recorded and compared. All patients had ejection fractions > 40%.Results; Early mitral flow peak velocity was higher in patients with acute regurgitation (peO.001). The mitral A wave was absent in five patients with acute regurgitation. In contrast, a prominent reverse atrial pulmonary systolic wave AR was demonstrated in these patients. Peak diastolic velocity of the pulmonary venous flow was greater in patients with acute aortic regurgitation (0.76 i 0.13) than in patients with chronic aortic regurgitation (0.40 i 0.09) (peO.001). Peak systolic velocity did not differ significantly between the two groups. The systolic fraction of pulmonary venous flow in patients with acute aortic regurgitation was lower (0.43 i 0.05) than that of patients with chronic regurgitation (0.63 f 0.1) (pe0.01). All patients with acute aortic regurgitation had an S/D ratio e 1, while those with chronic regurgitation had an S/D >1 (p< 0.001) and an WA e 1.
Rev. salud pública. 14 sup (1) RESUMENEl fenómeno de la violencia organizacional es de gran amplitud y complejidad. Esto se debe a la multiplicidad de factores y de elementos de orden individual, económico, social y político que allí tienen lugar. Este trabajo aborda inicialmente el problema de la violencia en general para luego tratar de precisar el problema de la violencia en el trabajo. Hoy día este es un campo amplio de investigación. Sin embargo en Colombia aun resta hacer esfuerzos para comprender este fenómeno en un entorno de marcado por la violencia política y social, en el marco de las cuales se están sucediendo rápidas transformaciones en las formas de organización del trabajo. Nuestro método de trabajo está basado en la realización de entrevistas semi-directivas con trabajadores que han experimentado alguna forma de violencia en el trabajo. El análisis desarrollado permite identifi car algunos de los agentes precursores de violencia en las organizaciones y las formas de manifestación de estas tienen en el seno de las organizaciones.Palabras clave: Violencia, ergonomía, control del riesgo, análisis y desempeño de tareas (fuente: DeCS, BIREME) ABSTRACTThe phenomenon of the organizational violence is extent and complex; this is due to the multiplicity of factors and of elements of individual, economic, social and political order that there take place. This work approaches initially the problem of the violence in general then to try to specify the problem of the work violence. Today this one is a wide fi eld of investigation nevertheless in Colombia even it remains to do efforts to understand this phenomenon in an environment of political and social violence, in the frame of which rapid transformations are happening in the forms of organization of the work. Our method of work this one based on the accomplishment of semi-
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.