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Binary blends with poly(4-vinyl pyridine) (P4VPy) 160,000 g/mol and poly(2-vinyl pyridine) (P2VPy) 159,000 g/mol as polymer components and 4,4’-thiodiphenol (TDP), 4,4’-methylendiphenol (MDP), 2,2’-biphenol (22BP) and 4,4’-biphenol (44BP) as low molecular weight compounds (LMWCs), were prepared. Miscibility between the components was analyzed by Fourier Transform Infrared Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC). Thermogravimetric Analysis (TGA) and Scanning Electron Microscopy (SEM) were also used as complementary techniques. Hydrogen bonding formation was detected by FTIR due to the increasing of the wave number corresponding to the deformation absorption of pyridine groups in P4VPy and P2VPy. A decreasing of melting points and fusion heats of the LMWCs is observed by DSC, which shows a lower crystallinity level as the blends are richer in the polymer component as a consequence of the intermolecular interaction. A plasticizing effect is also observed by DSC when P4VPy is blended with TDP and MDP; the higher steric hindrance prevents this effect when P2VPy is blended with 22BP and 44BP. Miscible blends were obtained with a moderate trend to a higher interaction degree in blends containing P4VPy. This report is the fifth part of a series of works including polymer-LMWC blends. Variables such as molecular weight increase in P4VPy and steric hindrance in P2VPy have been comparatively analyzed with blends previously reported.

Existe una gran diversidad de definiciones de estilo y numerosos cuestionarios para determinarlos; las clasificaciones son heterogéneas y el significado de los diferentes estilos no es coincidente. Con objeto de clarificar algunos puntos, este trabajo presenta una nueva herramienta, el cuestionario Escanero - Soria de estilos de aprendizaje (CESEA), y compara los resultados encontrados con los proporcionados por el cuestionario Honey - Alonso de estilos de aprendizaje (CHAEA), uno de los más utilizados en el ámbito hispanoparlante. Los resultados muestran diferencias principalmente en lo que respecta al estilo activo, siendo más homogéneos y elevados en el nuevo cuestionario. Dados los valores de fiabilidad encontrados y su mayor omogeneidad, se recomienda la utilización del CESEA para determinar los estilos de aprendizaje en los estudiantes de odontología con el objetivo de mejorar los menos desarrollados., There is a great diversity of style definitions and numerous questionnaires to determine them; the classifications are heterogeneous and the meaning of the different styles does not coincide. In order to clarify some points, this work presents a new tool, the Escanero-Soria questionnaire on learning styles (CESEA), and compares the results found with those provided by the Honey-Alonso questionnaire on learning styles (CHAEA), a one of the most used in the Spanish-speaking world. The results show differences mainly with regard to the active style, being more homogeneous and higher in the new questionnaire. Given the reliability values found and their greater homogeneity, the use of the CESEA is recommended to determine learning styles in dental students with the aim of improving the less developed., Facultad de Odontología

El objetivo de este estudio fue conocer los estilos de aprendizaje y su distribución en estudiantes del segundo año. Se realizó un estudio de diseño transversal. La muestra quedó constituida por 72 estudiantes de ambos sexos, matriculados en el segundo año de la carrera de Odontología de la Universidad Nacional de La Plata. A los alumnos involucrados se les aplicó el cuestionario de Honey-Alonso de 80 preguntas. El análisis estadístico de los resultados se realizó mediante el programa SPSS, con el empleo de estadísticos descriptivos, técnicas de análisis de varianza, un modelo lineal general y análisis de cluster. A partir de los resultados se calculó un índice de las preguntas respondidas positivamente con respecto al total de preguntas correspondientes a cada estilo. Teniendo en cuenta los resultados del cuestionario de Honey-Alonso, se calculó un índice de las preguntas respondidas positivamente con respecto al total correspondiente a cada estilo. El índice del estilo activo fue de 0,56, menor significativamente (p < 0,05) que el resto y no hubo diferencias significativas entre los otros estilos en estos estudiantes, ni tampoco en cuanto al sexo. Los estilos teórico, reflexivo y pragmático fueron más frecuentes en estudiantes universitarios de Odontología sin diferencias por sexo., The objective of this study was to know the learning styles and their distribution in second year students. A cross-sectional study was conducted. The sample consisted of 72 students of both sexes, enrolled in the second year of the Dentistry career at the National University of La Plata. The 80-question Honey-Alonso questionnaire was applied to the students involved. The statistical analysis of the results was carried out using the SPSS program, with the use of descriptive statistics, analysis of variance techniques, a general linear model and cluster analysis. From the results, an index of the questions answered positively with respect to the total of questions corresponding to each style was calculated. Taking into account the results of the Honey-Alonso questionnaire, an index of the questions answered positively with respect to the total corresponding to each style was calculated. The active style index was 0.56, significantly lower (p, Facultad de Odontología

Objetivo general del proyecto: Prevenir enfermedades gingivodentales relacionadas con el uso de piercing, con participación comunitaria que garantice un impacto en la salud de la población., Facultad de Odontología

Objetivo general del proyecto: Aumentar los niveles de salud mediante actividades preventivas, curativas y rehabilitadoras, recuperando la función y la estética de cada individuo., Facultad de Odontología

En el siguiente trabajo, se abordará un caso clínico, realizado en nuestro Servicio de Residencia, en el cual tuvimos la posibilidad de realizar una rehabilitación en el sector anterior con un implante de zirconio., Facultad de Odontología

The miscibility behavior in blends containing poly(4-vinyl pyridine) (P4VPy) and poly(2-vinyl pyridine) (P2VPy) as polymer components and the dihydric phenols 4,4'-thiodiphenol (TDP) and 4,4'-methylendiphenol (MDP) as low molecular weight compounds (LMWC), was studied by Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared Spectrophotometry (FTIR) as main analytical techniques. The glass transition of P4VPy and the melting of TDP and MDP, were found to be significantly affected when the compounds were blended. This result was attributed to the miscibility between thern, as a direct consequence of the specific interactions between the blend components. FTIR was used to investígate these interactions. The formation of intermolecular hydrogen bonds between the pyridine nitrogen atoms and the hydroxyl groups of TDP and MDP were discovered. When P2VPy was the macromolecular component, a difference was observed in the DSC behavior, which was attributed to a steric hindrance effect. Thermogravimetric and viscometry analysis were also used as additional techniques to complement the FTIR and DSC measurements performed.