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This study aims to examine the validity and reliability of the Elderly EXERNET Physical Activity Questionnaire (EEPAQ) in a sample of Spanish elderly population. A sample of 73 elderly successfully completed the EEPAQ and wore an accelerometer over 7 consecutive days. Test-retest reliability of the EEPAQ was assessed by having the participants answer the EEPAQ twice within 14 days. Criterion validity was assessed for the questionnaire against the accelerometer, as the gold standard. Results indicated that EEPAQ had adequate reliability measured by Intraclass correlation coefficient (ICC) (walking ICC=0.88; sitting ICC=0.68; household activities ICC=0.97), and good validity against the accelerometer. Walking had a significant (p

The p-n junction is the fundamental form of an electronic semiconductor device. A p-CuO/n-ZnO heterojunction diode was formed by using thermal evaporation and thermal oxidation techniques. Cupric oxide (CuO) films of 300 µm in thickness were obtained by thermal oxidation of Cu foils. Zinc oxide (ZnO) films of 30 µm in thickness were prepared in two process steps: firstly, thermal evaporation of Zn at atmospheric pressure, and then thermal oxidation to Zn films. The p-CuO/n-ZnO heterojunction diode was formed by performing the steps of ZnO deposition on the surface of the CuO films, and completed by deposition of silver electrical contacts on the top and on the bottom sides of the heterostructure. Structural, morphological, and electrical properties of CuO and ZnO were studied by X-ray diffraction (XRD), Raman spectroscopy, Uv–Vis DRS, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Hall effect techniques. Current-voltage (I-V) measurements were performed to the p-CuO/n-ZnO heterojunction diode. Structural characterization to CuO confirmed that pure, crystalline and (1 1 1) textured films can be obtained by thermal oxidation of Cu. ZnO films showed a polycrystalline structure without preferred orientation. The band gap of CuO and ZnO were 1.51 and 3.21 eV, respectively. Cross-sectional SEM and TEM images confirmed the formation of the p-CuO/n-ZnO heterojunction diode. Hall measurements confirmed the p-type conductivity of CuO and the n-type conductivity of ZnO. Also, the carrier concentration and Hall mobility of CuO films were 9.54 × 1012 cm−3 and 267 cm2 V−1 s−1, respectively. ZnO films exhibited a carrier concentration and Hall mobility of 3.69 × 1012 cm−3 and 22.18 cm2 V−1 s−1, respectively. The I-V measurement showed that the p-CuO/n-ZnO heterojunction exhibits a low turn-on voltage of about 0.8 V and a breakdown voltage of about 38 V. Electrical parameter such as rectification ratio and ideality factor were also calculated. An energy band-diagram of the CuO/ZnO heterojunction was proposed, where a built-in voltage of 0.57 eV was observed.

Resumen Introduccion y objetivos La prevalencia de la obesidad infantil ha aumentado en las ultimas decadas. El objetivo fue determinar si una intervencion durante 3 meses de actividad fisica desarrollada en la escuela puede reducir la tendencia al sobrepeso y los factores de riesgo derivados de la obesidad en ninos. Metodos Participaron voluntariamente en el estudio (descriptivo-transversal) 137 ninos (media de edad, 12 ± 1 anos). Los ninos se distribuyeron de manera voluntaria en uno de los siguientes grupos: a ) grupo sedentario (2 h/semana de educacion fisica en la escuela); b ) grupo activo (2 h/semana de educacion fisica en la escuela, mas 3 h/semana extra), y c ) grupo de deportes (2 h/semana de educacion fisica en la escuela, mas 5 h/semana extra). Se determinaron las caracteristicas antropometricas, la presion arterial, la condicion fisica (estimada por la prueba de Course-Navette) y los parametros bioquimicos relacionados con factores de riesgo cardiovascular. Resultados El peso, el indice de masa corporal, la circunferencia de la cintura, la suma de pliegues cutaneos, el porcentaje de grasa corporal y el indice de masa grasa de los ninos disminuyeron en funcion del nivel de actividad, mientras que el contenido en agua aumento con la actividad. Los parametros relacionados con el riesgo cardiovascular trigliceridos, insulina, presion arterial sistolica e indice homeostatic model assessment presentaron valores mas bajos en el grupo de deportes. El consumo maximo de oxigeno y la frecuencia cardiaca maxima (prueba de Course-Navette) aumentaron progresivamente con la actividad. Los ninos que hicieron un total de 7 h/semana de actividad fisica presentaron una odds ratio significativamente menor de tener elevados los siguientes factores de riesgo cardiovascular: circunferencia de cintura, indice de masa grasa e indice homeostatic model assessment . Conclusiones La actividad fisica es esencial para que los ninos mantengan un buen estado metabolico de salud. Los ninos con mayores niveles de actividad fisica presentan mejores perfiles antropometricos y bioquimicos.

SiO2–Ag wires were synthesized by a sol–gel technique. A two step approach was followed, focusing mainly on the effect of acid concentration on the first stage and processing temperature on the second. This acid-catalyzed reaction on the first stage yielded SiO2–AgCl wires with diameters as low as 800 nm average, and lengths ranging up to 100 μm, as determined by LV-SEM and TEM. A thermal treatment at different temperatures on the second step, under H2 atmosphere, yields silica–silver unidirectional structures. The chemical composition of these structures was determined by EDS, indicating the presence of Si, O and Ag. The transformation of the wires as a function of temperature under reducing atmosphere was followed by electron microscopy analysis. At 400 °C and above the silica starts to cover the reduced silver while maintaining the unidirectional conformation, suggesting a tendency to form silver wires covered by a silica layer.

It has been reported that exercise induces oxidative stress and causes adaptations in antioxidant defences. The aim of this study was to determine the adaptations of lymphocytes to the oxidative stress induced by an exhaustive exercise. Nine voluntary male subjects participated in the study. The exercise was a cycling mountain stage (171.8 km), and the cyclists took a mean of 283 min to complete it. Blood samples were taken the morning of the cycling stage day, after overnight fasting, and 3 h after finishing the stage. We determined the blood glutathione redox status (GSSG/GSH), lymphocyte antioxidant enzyme activities and superoxide dismutase (SOD) levels; the plasma and lymphocyte vitamin E levels; the serum lactate dehydrogenase (LDH) and creatine kinase (CK) activities and urate levels; the plasma carotene and malonaldehyde (MDA) levels; and the lymphocyte carbonyl index. The cycling stage induced significant increases in blood-oxidized (glutathione/GSSG), plasma MDA and serum urate levels. The exercise also produced increases in CK and LDH serum activities. The mountain cycling stage induced significant increases in lymphocyte vitamin E levels, glutathione peroxidase and glutathione reductase activities as well as increased SOD activity and protein levels. The protein carbonyl levels increased significantly in lymphocytes after the stage. In conclusion, in spite of increasing antioxidant defences in response to the oxidative stress induced by the exhaustive exercise, lymphocyte oxidative damage was produced after the stage as demonstrated by the increased carbonyl index even in very well trained athletes.

The aim of this work was to evaluate the effect of different intensity of exercise and different training status on antioxidants and cholesterol profile in cyclists. 33 male cyclists (17 amateur and 16 professional cyclists) participated in this study. The amateurs all trained 14 +/- 1 h each week, and their VO(2) max was 62.5 +/- 1.8 ml/Kg x min; the professionals all trained 24 +/- 1 h each week, and their VO(2) max was 80.2 +/- 1.6 ml/Kg x min. Amateurs were submitted to the maximal and submaximal prolonged exercise tests. Professionals were submitted to a mountain stage (170 km) of cycling competition. Serum lipid and cholesterol profile (triglycerides, total cholesterol, HDL-cholesterol, LDL-cholesterol and VLDL-cholesterol) and plasma antioxidant capacity (ascorbic acid, alpha-tocopherol, retinol, beta-carotene and others) were measured before and after exercise tests. Hematological determinations (number of erythrocytes, hematocrit and hemoglobin concentration) and dietary intake were also measured. No significant differences were observed in basal values (before exercise tests) of amateur and professional cyclists. Negligible differences were found between dietary intake of amateur and professional cyclists, and also the results of hematological values showed there was no effect of degree of hydration or dietary intake on blood levels of studied antioxidant and lipid parameters. An increase in plasma levels of vitamin C, vitamin E, triglycerides and VLDL-cholesterol levels, and also a decrease of beta-carotene and LDL-cholesterol. were observed in well-trained professional cyclists after the cycling stage - an endurance exercise--but not in amateur cyclists. Amateur cyclists showed only mild increases in total cholesterol after maximal and submaximal exercise, while a rise in HDL-cholesterol was only observed after maximal exercise; none of these changes were observed in professional cyclists. Plasma levels of antioxidant vitamins and carotenes, and also serum lipids, total cholesterol and lipoprotein-cholesterol showed an overall response to exercise, and their increase and/or decrease must be explained as a consequence of the different training status of sportsmen and intensity and duration of exercise tests.