Evaporative cooling systems are a widely used technique in Mediterranean greenhouses. In this study, the cellulose evaporative cooling pads most commonly used in this region were tested in the laboratory using a new methodology in a wind tunnel to determine the water flow on the pad and air flow through it, as well as the water consumption and pressure drop caused by each pad as a function of air speed. Greater water flow increased the pressure drop, but the main effect on performance was caused by modifying the air flow through the pad. We recommend a range of air speeds through the pad of 1 to 1.5 m s -1 , at which the pressure drop was between 3.9 and 11.25 Pa, depending on the type of pad and the water flow applied. On the other hand, saturation efficiency ranged between 64% and 70%, while the amount of evaporated water varied between 1.8 and 2.62 kg h -1 K -1 per square meter of pad area.

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The aim of the present study was to evaluate geometrical characteristics and airflow resistance of eleven different insect-proof screens by three different experimental procedures: equipment based in water-flow suction, low-speed wind tunnel, and CFD simulations. The two first arrangements had the same principle, in that air was forced through the test samples in order to create a pressure drop. Last analyses were carried out by numerical simulations of airflow through insect-proof screens using a commercial fluid dynamics code based in Finite Element method (ANSYS/ FLOTRAN v8.0). Previously, an analysis images system, called EUCLIDES v1.1, was designed with MS Visual Basic 6.0 running under MS Windows, for the analysis of the screens samples images captured with a microscope. A geometrical characterization of the eleven screens materials was carried out using this software tool. The software allows to determine all the geometric parameters that characterize the screens, as thread diameter and distances between two adjacent threads in two directions, from the four coordinates that defined each pore. The results obtained in this work show that the eleven screens can be classed in three groups, corresponding with the fibre density, with similar porosity and airflow properties (permeability and inertial factor). However, sample 8 has a small thread diameter and screen thickness that decreased the pressure drop coefficient. The results suggest that equations based on the porosity of the screen and the Reynolds number can be used to calculate the pressure drop coefficient.

El fútbol es un deporte colectivo donde, para alcanzar el éxito, los jugadores necesitan de habilidades técnicas, tácticas y físicas, fundamentalmente de carácter intermitente siendo éstas acciones las que determinan el rendimiento. Un ejemplo de acciones de este tipo son los saltos. Este gesto deportivo esta correlacionado con la fuerza máxima, entendiendo que una mayor producción de fuerza permite una mayor generación de altura en dicho gesto. El objetivo de este trabajo es estudiar el efecto de entrenamiento de fuerza en sistema isoinercial sobre la mejora del Salto con Contramovimiento y analizar los cambios en la altura del mismo después de un programa de entrenamiento de 15 semanas, realizado sobre jóvenes futbolistas de élite. Los resultados obtenidos, muestran que no existen cambios significativos en esta variable de análisis (p< 0,05) por lo que se concluye que este tipo de entrenamiento con la duración especificada no tiene efectos sobre el rendimiento en la altura del salto (CMJ).Palabras clave: Entrenamiento Isoinercial, Futbolistas, Rendimiento, CMJ.Abstract: Soccer is a team sport where, to achieve success, players need of technical, tactical and physical skills, mainly intermittent character being such actions which determine the performance. An example of such actions is the jumpers. This sports actions is correlated with the maximal strength, understanding that force production allows greater height in this actions. The aim is to study the effects of strength training using a isoinertial device on Countermovement Jump ability and to analyze the changes in height after 15 weeks program training in young elite soccer players. There are no significant changes after to analyze the results (p< 0,05), so it is concluded that this type of training with certified duration has no effect on performance in height jump (CMJ).Keywords: Isoinertial Training, Soccers Players, Performance, CMJ.

La fuerza parcial soportada por los miembros inferiores en un eje transversal durante cambios de dirección parece ser determinante para la aparición de lesiones de rodilla. El objetivo de este estudio es conocer el genu varo y valgo soportado por la articulación durante cambios de dirección en sujetos físicamente activos. Cincuenta y seis sujetos participaron de manera voluntaria en el estudio (24.26 ± 2.3 años; altura = 1.79 ± 0.07 m; peso = 75.48 ± 13.71 kg; IMC = 24.16 ± 3.28 kg·m-2). Llevaron a cabo 3 cambios de dirección diferentes: 30º, 45º y 45º al mismo lado (45ml) de su pie dominante (cambio cerrado). Nuestros resultados nos indican que tanto la fuerza en valgo como en varo fue mayor en cambios a 30º (Valgo: 37.57 N SD±45.73; Varo: 721.92 N SD±250.52) respecto a cambios de 45º (Valgo: 27.89 N SD±50,92; Varo: 696.42 N SD±252,70), aunque estas diferencias no fueron estadísticamente significativas (p>0.05). En cuanto a los cambios cerrados, la fuerza media en valgo fue de 1890,01 N (SD±94,18). El valgo en cambios cerrados fue también mayor respecto al valgo en 30º como al valgo en 45º, aunque no significativamente (p=0.07). Por otro lado, los cambios cerrados producen una fuerza también mayor en valgo que en cambios abiertos (45º y 30º). Estudios posteriores deberían analizar el ángulo de varo y valgo en el cambio de dirección para relacionarlo con los niveles de fuerza ejercidos en ese eje.Palabras clave: valgo, varo, rodilla, cambios de dirección, riesgo de lesión.Abstract: The peak force of lower limb in transverse axis during sidecutting may determinate the develop of knee injuries. The aim of this study was to know the valgus and varus of the knee joint during sidecutting in physically active people. Fifty-six physically active people participated in the study voluntarily (24.26 ± 2.3 years; height = 1.79 ± 0.07 m; weight = 75.48 ± 13.71 kg; BMI = 24.16 ± 3.28 kg·m-2). They made three different sidecuttings: 30º, 45º and 45º in the same way (45 ml) from their dominant foot (closed sidecutting). Our results indicate that the peak force in valgus and varus was bigger in 30º sidecuttings (Valgus: 37.57 N SD±45.73; Varus: 721.92 N SD±250.52) than 45º sidecuttings (Valgus: 27.89 N SD±50,92; Varus: 696.42 N SD±252,70), although these differences were not statistically significant (p>0,05). In the closed sidecuttings, the mean force in valgus was 1890,01 N (SD±94,18). The valgus in closing sidecuttings was bigger than valgus in 30º and 45º sidecuttings too, although not statistically significant (p=0,07). On the other hand, closed sidecuttings produce a peak force bigger in valgus than open sidecuttings (30º and 45º). Subsequent studies must analyze the varus and valgus angle in the sidecutting to be compared with peak force in this axis. Key words: valgus, varus, knee, sidecutting, injury risk.