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In the present study, attention was focused on the adaptation of different methods in order to incorporate reinforcement materials just like SiC and B4C to carbon fiber reinforced carbon matrix (C/C) composites. Hot petroleum pitch impregnation and also at room temperature, and toluene were used as drivers to incorporate reinforcement materials and oxidation inhibitors, just like B2O3, H3BO3 and B4C to (C/C) matrix. Hermetic crucibles and graphite have been used in order to obtained carbonization process. Oxidizing atmospheres were used in order to improve the oxidation matrix after the carbonization process. Different methods of infiltration have been evaluated in order to test which of these produce bigger increment on mechanical properties and oxidation protection of the final materials. The different tested materials were studied by means of techniques like scanning electron microscopy (SEM) and micro-analysis by energy dispersive spectroscopy (EDS). Results of flexural test were finally compared.El objeto del presente trabajo consiste en adecuar distintos métodos para la incorporación de materiales de refuerzo como el SiC y B4C a materiales compuestos de carbono, reforzados con fibra de carbono. Se utilizaron breas de impregnación de petróleo (en frío y en caliente) y tolueno como vehículos para la incorporación de los materiales de refuerzo y materiales inhibidores de oxidación como B2O3, H3BO3 y B4C a las matrices de C/C. Se utilizaron crisoles herméticos con grafito en polvo en su interior para obtener la carbonización de las muestras. Se emplearon atmósferas fuertemente oxidantes para provocar la oxidación y degradación de la matriz compuesta tras el proceso de carbonización. También se evaluaron cuáles de los métodos ensayados producen un mayor incremento de las propiedades mecánicas y protección contra la oxidación de los materiales finales obtenidos. Los distintos materiales ensayados fueron estudiados mediante técnicas como microscopía electrónica de barrido y microanálisis mediante energías dispersivas. Así mismo, se evaluaron los resultados de los ensayos de flexión obtenidos.

Introducción y objetivos: examinar la asociación del apoyo de los padres y de los amigos con diferentes intensidades de actividad física durante el tiempo libre de adolescentes españoles de ambos sexos.Métodos: un total 352 adolescentes españoles (51.70% chicos; 12-16 años) cumplimentaron el International Physical Activity Questionnarie for Adolescents y un cuestionario validado sobre apoyo social. Se realizaron análisis de regresión linear ajustados por edad.Resultados: el apoyo social de padres y amigos influyó positivamente sobre los niveles de actividad física vigorosa que los adolescentes españoles realizan durante su tiempo libre (β=.226 y β=.285 en chicos y β=.167 y β=.181 en chicas, para el apoyo de padres y amigos respectivamente) y sobre los de intensidad moderada en el caso de las chicas (β=.195 y β=.200, respectivamente).Conclusiones: el apoyo de padres y amigos contribuye a los niveles de actividad física moderada o vigorosa en adolescentes españoles.

The four serotypes of dengue flaviviruses are transmitted mainly by the Aedes aegypti mosquito, and some epidemics have been attributed to Ae. albopictus, Ae. polynesiensis, and various species of the Ae. scutellaris complex. The risk factors involved in dengue mortality and morbidity are related to the human host (genetic characteristics of infected persons; lifestyles, immune status, and health conditions of people; basic sanitation of dwellings; and water supply) and to the virus (genetic variability between and among serotypes, different pathogenicities, and geographic distribution). Notwithstanding the lack of knowledge of the immunopathobiology of dengue fever, important advances have been made in terms of a protective immune response, using attenuated dengue viruses or antigens produced by means of recombinant technologies. Efforts have been made since the 1940s to develop dengue vaccines. Immunity acquired from natural infection is specific for each serotype, and as many as three different serotype infections have been reported in one individual. For this reason, a tetravalent vaccine may likely be needed. Candidate vaccines against the four serotypes have been tested in volunteers and have proven to be immunogenic and safe. Although attenuated live virus vaccines are promising, more study is needed regarding their effectiveness and safety. Currently, several studies are ongoing to develop dengue vaccines using antigens from structural proteins (particularly E glycoprotein) and nonstructural proteins, with recombinant DNA technology and other biomolecular technologies. With the same goal, various expression vectors are being used, including Escherichia coli, baculovirus, vaccinia virus, and yellow fever virus. Unfortunately, no satisfactory results have been obtained in humans. The need for effective dengue vaccines is great, given the serious worldwide problem of the transmission of the four serotypes. Effective immunization against dengue would contribute to its prevention, with a positive cost-benefit relationship. Endemic dengue affects young children, and they should be immunized through the Expanded Program on Immunization.

Objective: To evaluate the usefulness of magnetic resonance (MR) for investigating bone involvement in Gaucher disease type 1 (GD)., Methods: Ten adult patients with the diagnosis of GD type 1 were studied. Weighted sequences were performed in spin-echo (SE) T1 and T2 of 4 body areas: spine, pelvis, hips, and femurs. The patterns of bone infiltration proposed for the study were: homogeneous infiltration (H), non-homogeneous infiltration (NH), and normality (N). Four patients were receiving enzyme replacement therapy., Results: All patients (100%) showed changes associated with infiltration with Gaucher cells. The distribution of patterns was as follows: the homogeneous pattern predominated (60 and 50%, respectively) in spine (6H/2NH/2N) and pelvis (5H/3NH/2N), whereas the non-homogeneous pattern predominated (60% and 80%, respectively) in hips (1H/6NH/3N) and femurs (1H/8NH/1N). As bone complications two cases of hip avascular necrosis were noted, one of them with bilateral involvement, one case with infarcts in femur diaphysis and other case with medullar edema in a bone crisis., Conclusion: MR is an excellent technique for detecting medullar bone infiltration and complications in GD type 1.

Hypophyseal adenomas are the most frequent intrasella tumours. They are classified as macroadenomas or as microadenomas depending on whether their size is greater or less than 1 cm. Hypophyseal tumours may undergo ischaemic necrosis and haemorrhage when the blood supply is reduced. Intratumoural bleeding is found in varying percentages, between 9.9% and 26%. We review our series of 122 patients with hypophyseal adenomas in whom MR was done. Signs of bleeding were found in 12 patients (9%). In five cases, bleeding had presented as hypophyseal apoplexy, in five cases with subacute symptoms and in two cases was asymptomatic and diagnosis fortuitous. Of the adenomas with intratumoural bleeding, 9 were functioning tumours (4 secreted PRL, 4 ACTH and 1 GH) and 3 non-functioning. The risk factors considered in the pathogenesis of intratumoural bleeding are numerous. The increased incidence of bleeding in large and in invasisve adenomas, especially when treated with bromocriptin, is well established. MR is the ideal technique to detect intratumoural bleeding, T2 weighted sequences being very useful in the diagnosis of bleeding in the acute phase. In the subacute phase, focal areas of hyperintensity are seen in T1 and of hypo/hyperintensity in T2. In the chronic phase, areas of hypodensity are seen both in T1 and in T2. In our study we analyze the clinico-radiological correlation in patients with signs of intratumoural bleeding.