Medición de la actividad física en la población española mediante cuestionarios: direcciones futuras de investigación

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Effect of key parameters on the removal of formaldehyde and methanol in gas-phase biotrickling filters

The effect of some important operation parameters, as pH, pollutant load and composition of the nutrient media, on the biodegradation of a mixture of formaldehyde and methanol in a gas-phase biotrickling filter was studied. pH proved to affect the degradation of both compounds at moderately acidic values. Replacing ammonium with nitrate as nitrogen source in the liquid solution led to a slight decrease in performance, though this difference was not really significant. A slight decrease in the elimination rate was also observed when reducing the N–NO3− concentration to 60% of its original value. No interactions between the two pollutants were found under our working conditions

Treatment of gas-phase methanol in conventional biofilters packed with lava rock

The performance of laboratory scale methanol-degrading biofilters packed with lava rock was checked during almost 1 yr under different conditions. The biomass concentration and biomass adaptation of the inoculum dramatically affected the start-up and the performance of the systems during the first stages of operation. A fast start-up was obtained when using concentrated and adapted inocula, while diluted or non-adapted inocula proved to be much less efficient. The performance of the reactor during long-term operation was significantly affected by the toxic load and moisture content of the gas. Critical loads between 120 and 280 g/m3h were reached during different phases of the study. The reactor had a high stability to EBRT changes when working at values between 48.0 and 91.1 s, showing little or no negative effect when decreasing the EBRT. Hardly any difference was observed regarding performance when using either a downflow or upflow feed, although slightly better results were obtained when working in a downflow mode

Biofiltration of waste gases containing a mixture of formaldehyde and methanol

Several biofilters and biotrickling filters were used for the treatment of a mixture of formaldehyde and methanol; and their efficiencies were compared. Results obtained with three different inert filter bed materials (lava rock, perlite, activated carbon) suggested that the packing material had only little influence on the performance. The best results were obtained in a biotrickling filter packed with lava rock and fed a nutrient solution that was renewed weekly. A maximum formaldehyde elimination capacity of 180 g m−3 h−1 was reached, while the methanol elimination capacity rose occasionally to more than 600 g m−3 h−1 . Formaldehyde degradation was affected by the inlet methanol concentration. Several combinations of load vs empty bed residence time (EBRTs of 71.9, 46.5, 30.0, 20.7 s) were studied, reaching a formaldehyde elimination capacity of 112 g m−3 h−1 with about 80% removal efficiency at the lowest EBRT (20.7s)

Optimization of nutrient supply in a downflow gas-phase biofilter packed with an inert carrier

Several methodologies were tested to supply nutrients to a downflow biofilter packed with perlite and used to treat toluene-polluted air. Despite the presence of an inorganic carrier, elimination capacities of up to around 60 g/m3 per hour could be maintained when a basal medium, containing nitrogen, phosphorus and potassium, was supplied once every fortnight or even once a month rather than once a week. Experimental results also indicated that the addition of vitamins or trace minerals to the basal aqueous medium hardly improved biofilter performance. Furthermore, the nutrient supply could be combined with a biomass control strategy, using air sparging, without any adverse effect on biofilter performance compared to supplying nutrients alone, and limiting the accumulation of excess biomass on the packing material. The performance of the biofilter was not significantly affected by temperature fluctuations between 25 and 33 °C

Encuesta nacional de tendencias de fitness en España para 2017

Every year for the past 10 years, the American College of Sports Medicine (ACSM) has administered a global survey on fitness trends. This study has reproduced the methodology used by the ACSM surveys with the goal of identifying trends in the fitness sector in Spain. The opinion of 672 professionals in the fitness sector about 40 potential trends in the sector for 2017 were gathered via an online questionnaire. The results are compared and discussed with the results of the international surveys administered by the ACSM from 2007 to 2016. The results show that the trends in the fitness sector in Spain for 2017 largely dovetail with those found in the ACSM’s last international survey for 2016. Thus, 14 of the trends within the Top 20 are identical in both studies, with the top positions being “body weight training”, “high-intensity interval training” and “certified, experienced trained staff”. On the other hand, 4 trends in Spain’s Top 20 were specific to our country. Likewise, 12 of the identified trends match the Top 20 ranked trends in the past decade (2007-2016) devised based on the results of the ACSM’s international surveysDurante los últimos 10 años el Colegio Americano de Medicina del Deporte (American College of Sports Medicine, ACSM) realiza anualmente una encuesta global sobre tendencias de fitness. El presente estudio ha reproducido la metodología empleada en las encuestas de la ACSM y ha tenido como objetivo identificar tendencias en el sector del fitness en el ámbito español. La opinión de 672 profesionales del sector del fitness sobre 40 potenciales tendencias en el sector para el año 2017 se recogió mediante un cuestionario en línea. Los resultados obtenidos se comparan y discuten con los resultados de las encuestas internacionales realizadas por ACSM desde 2007 a 2016. Los resultados muestran que las tendencias en el sector del fitness en España para el año 2017 coinciden, en términos generales, con las encontradas en la última encuesta internacional de la ACSM para el año 2016. Así, 14 de ellas coinciden dentro del Top 20 en ambos estudios, destacando en los primeros lugares “el entrenamiento con peso corporal”, “el entrenamiento interválico de alta intensidad”, y “el personal formado cualificado y experimentado”. Por otro lado, 4 tendencias del Top 20 fueron tendencias específicas de nuestro país. Del mismo modo, 12 tendencias identificadas coinciden con el Top 20 del ranking de las tendencias de la última década (2007-2016) elaborado a partir de los resultados de las encuestas internacionales de la ACS

Removal of formaldehyde, methanol, dimethylether and carbon monoxide from waste gases of synthetic resin-producing industries

The removal of mixtures of gas-phase pollutants released from formaldehyde- and formaldehyde resin-producing industries was studied in different bioreactor systems. The waste gases contained formaldehyde, methanol, dimethylether and carbon monoxide. The use of a hybrid two-stage bioreactor, composed of a biotrickling filter and a conventional biofilter connected in series, led to very high elimination capacities and removal efficiencies close to 100% for overall pollutant loads exceeding 600 g m−3 h−1. The presence of low concentrations of dimethylether in the gaseous mixture did not have a significant effect on the removal of formaldehyde or methanol under our operating conditions, although moderate concentrations of these compounds did negatively affect the biodegradation of dimethylether. When a mixture of all four compounds, at concentrations around 100, 100, 50 and 50 mg m−3 for formaldehyde, methanol, carbon monoxide and dimethylether, respectively, was fed to a conventional biofilter, removal efficiencies higher than 80% were obtained for the first three pollutants at empty bed retention time values above 30 s. On the other hand, dimethylether was removed to a lower extent, although its reduced environmental impact allows to conclude that these results were satisfactory

Enquesta nacional de tendències de fitnes a Espanya per al 2017

Durant els últims 10 anys el Col·legi Americà de Medicina de l’Esport (American College of Sports Medicine, ACSM) realitza anualment una enquesta global sobre tendències de fitnes. El present estudi ha reproduït la metodologia emprada en les enquestes de l’ACSM i ha tingut com a objectiu identificar tendències en el sector del fitnes en l’àmbit espanyol. L’opinió de 672 professionals del sector del fitnes sobre 40 potencials tendències en el sector per a l’any 2017 es va recollir mitjançant un qüestionari en línia. Els resultats obtinguts es comparen i discuteixen amb els resultats de les enquestes internacionals realitzades per ACSM des del 2007 al 2016. Els resultats mostren que les tendències en el sector del fitnes a Espanya per a l’any 2017 coincideixen, en termes generals, amb les oposades en l’última enquesta internacio­nal de l’ACSM per a l’any 2016. Així, 14 d’elles coincideixen dins del Top 20 en tots dos estudis, destacant en els primers llocs “l’entrenament amb pes corporal”, “l’entrenament intervàlic d’alta intensitat”, i “el personal format qualificat i experimentat”. D’altra banda, 4 tendències del Top 20 van ser tendències específiques del nostre país. De la mateixa manera, 12 tendències identificades coincideixen amb el Top 20 del rànquing de les tendències de l’última dècada (2007-2016) elaborat a partir dels resultats de les enquestes internacio­nals de l’ACSM

Judo infantil. Educación integral

José Santos Nalda. Barcelona: Editorial Alas, 2003. 205 páginas. 24x17 cm. I.S.B.N.: 84-203-0423-9

Judo infantil. Educación integral

José Santos Nalda. Barcelona: Editorial Alas, 2003. 205 páginas. 24x17 cm. I.S.B.N.: 84-203-0423-9