This study evaluates the effect of recycled thermoplastic polyurethane (RTPU) on the Izod impact resistance of polypropylene (PP) compounds with 50% coconut fibers arranged randomly. The Izod impact ...resistance was compared to the performance of a commercial coupling agent (CCA) of maleic anhydride grafted PP copolymer (MAPP). The PP compounds were made with 0, 2.5, and 5% by weight of RTPU or CCA, and with 50% of short or long coconut fibers, in the form of plates molded by thermo-compression, where the plastic components were previously extruded in the form of filaments. The morphology of the resulting materials was studied by scanning electron microscopy (SEM). The functional groups and their possible interactions present were determined by Fourier transform infrared spectroscopy (FTIR). Furthermore, the interfacial shear strength between the polymeric matrix and the coconut fiber was determined. The results showed a higher Izod impact resistance and a higher adhesion between long coconut fiber and PP when they contain 5% RTPU. This is explained by the higher interfacial shear strength between them given by the chemical and/or physical interaction between functional groups such as the lignin of coconut fibers and the isocyanate groups of RTPU, which in turn determined the shortest critical length of coconut fiber. The impact resistance values ranged from 19.8 to 24.4 J/m for mixtures of PP with short coconut fibers and 39.9–71.7 J/m for PP with long coconut fibers.
The 'FCSHlee' program proposed by ESPOL Polytechnic University's School of Social and Humanistic Sciences (FCSH, acronym in Spanish), consisted in the implementation of a reading requirement of ...culturally enriching book by subject. This study shares the experience of an academic literacy initiative in the Ecuadorian university, ESPOL's case. The program aimed to enhance undergraduate students' cultural level as well as oral and written communication skills. We develop a significant sample (N = 387) of the students that were part of the program and collected the data through surveys after its completion. The study describes details of the program, its scope, implementation, statistics, and conditions. Among the careers studied at the FCSH, Economics was the one that had a bigger margin of appreciation towards the program, which is a factor that could indicate that these groups of students possess reading orientation given the analytical characteristics of their study program.
Diffuse large B-cell lymphoma (DLBCL) patients are treated using relatively homogeneous protocols, irrespective of their biological and clinical variability. Here we have developed a ...protein-expression-based outcome predictor for DLBCL. Using tissue microarrays (TMAs), we have analyzed the expression of 52 selected molecules in a series of 152 DLBCLs. The study yielded relevant information concerning key biological aspects of this tumor, such as cell-cycle control and apoptosis. A biological predictor was built with a training group of 103 patients, and was validated with a blind set of 49 patients. The predictive model with 8 markers can identify the probability of failure for a given patient with 78% accuracy. After stratifying patients according to the predicted response under the logistic model, 92.3% patients below the 25 percentile were accurately predicted by this biological score as “failure-free” while 96.2% of those above the 75 percentile were correctly predicted as belonging to the “fatal or refractory disease” group. Combining this biological score and the International Prognostic Index (IPI) improves the capacity for predicting failure and survival. This predictor was then validated in the independent group. The protein-expression-based score complements the information obtained from the use of the IPI, allowing patients to be assigned to different risk categories.
Introducción: el control de la calidad del diagnóstico de las parasitosis intestinales es un proceder de gran importancia en la práctica de la salud pública; sin embargo, no está tan difundido como ...en otras ramas del diagnóstico del laboratorio clínico y solo ha sido incorporado en los últimos años. Objetivos: evaluar la calidad del diagnóstico parasitológico en cuatro municipios de La Habana. Métodos: el estudio se efectuó en 15 policlínicos de los municipios La Lisa, Arroyo Naranjo, La Habana del Este y Cerro, de la provincia de La Habana, en el período comprendido entre marzo de 2011 a mayo de 2012. El universo de trabajo estuvo constituido por 747 muestras de heces analizadas en los laboratorios de dichos policlínicos. Para determinar la concordancia entre observadores se calculó el coeficiente Kappa para dos observadores y dos categorías. Resultados: solo en un policlínico hubo grado de acuerdo casi perfecto en el diagnóstico parasitario (coeficiente de concordancia kappa de 0.90, p < 0,05). En una cuarta parte de los policlínicos evaluados fue posible establecer la concordancia en el diagnóstico parasitario y de ellos solo en uno hubo calidad satisfactoria. Conclusiones: los principales errores en el diagnóstico son para Ascaris lumbricoides y Blastocystis spp. Estos resultados sugieren perfeccionar constantemente la capacitación del personal que realiza este tipo de exámenes.
Introducción: el control de la calidad del diagnóstico de las parasitosis intestinales es un proceder de gran importancia en la práctica de la salud pública; sin embargo, no está tan difundido como ...en otras ramas del diagnóstico del laboratorio clínico y solo ha sido incorporado en los últimos años. Objetivos: evaluar la calidad del diagnóstico parasitológico en cuatro municipios de La Habana. Métodos: el estudio se efectuó en 15 policlínicos de los municipios La Lisa, Arroyo Naranjo, La Habana del Este y Cerro, de la provincia de La Habana, en el período comprendido entre marzo de 2011 a mayo de 2012. El universo de trabajo estuvo constituido por 747 muestras de heces analizadas en los laboratorios de dichos policlínicos. Para determinar la concordancia entre observadores se calculó el coeficiente Kappa para dos observadores y dos categorías. Resultados: solo en un policlínico hubo grado de acuerdo casi perfecto en el diagnóstico parasitario (coeficiente de concordancia kappa de 0.90, p < 0,05). En una cuarta parte de los policlínicos evaluados fue posible establecer la concordancia en el diagnóstico parasitario y de ellos solo en uno hubo calidad satisfactoria. Conclusiones: los principales errores en el diagnóstico son para Ascaris lumbricoides y Blastocystis spp. Estos resultados sugieren perfeccionar constantemente la capacitación del personal que realiza este tipo de exámenes.
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