Clasificación visual estructural de la madera de pino radiata procedente de Cataluña

Se han clasificado visualmente, según la norma española UNE 56544; 150 piezas de madera aserrada de pino radiata procedentes de Cataluña (España) con una sección de 80x150 mm y una longitud de 2.500 mm. Esta norma establece dos calidades visuales (ME-1 y ME-2) para piezas con grueso menor o igual que 70 mm y una única calidad visual (MEG) para gruesos mayores de 70 mm. Con el fin de conocer el efecto frontera entre la pequeña y la gran escuadría se clasificaron las piezas según ambas categorías. Se determinó la tensión de rotura en flexión, el módulo de elasticidad en flexión y la densidad de cada pieza mediante el ensayo de acuerdo con la norma UNE-EN 408 siguiendo los ajustes definidos en la norma UNE-EN 384. Un 53 % de las piezas se clasificaron como MEG con una resistencia característica a flexión de 28 N/mm2 y un valor medio del módulo de elasticidad de 9.900 N/mm2. Por otra, un 42 % de las piezas se clasificaron como ME-2 y sólo un 3 % como ME-1; en este caso las propiedades mecánicas de la calidad ME-2 no se alejan mucho de las de la calidad MEG. El elevado porcentaje de piezas rechazadas (47 % frente a la MEG) se debe principalmente al defecto de alabeo responsable de un 39 % de rechazo. Si no se considera el alabeo en la clasificación el porcentaje de rechazo desciende al 17 % y las propiedades mecánicas de la calidad MEG presentan un valor característico de resistencia a flexión de 21 N/mm2 y un módulo de elasticidad de 9.100 N/mm2. A sample of 150 pieces of radiata pine sawn timber with 180x120 mm in cross-section and 2.500 mm in length sourcing from Catalonia (Spain) were visually graded according to Spanish standard UNE 56544. This standard establish two visual grades (ME-1 and ME-2) for timber pieces with thickness equal or less than 70 mm, and one grade (MEG) for thickness bigger than 70 mm. In order to know the border effect between small and larger cross-section the pieces were graded in both categories. The modulus of rupture, modulus of elasticity and density were obtained by test according to EN 408 standard and the adjustments of EN 384. A 53 % of pieces were classified as MEG with a characteristic bending strength of 28 N/mm2 and a mean value of MOE of 9.900 N/mm2. On the other hand, a 42 % of pieces were classified as ME-2 and only a 3 % as ME-1; in this case the mechanical properties of ME-2 are not far from MEG properties. The high percentage of rejected pieces (47 % vs MEG) is mainly due to the twist defect with a 39 % of rejected pieces. If twist is not considered in the grading process the reject percentage decreases to 17 % and the mechanical properties of MEG grade present a characteristic value of bending strength of 21 N/mm2 and a MOE of 9.100 N/mm2

Using artificial intelligence (AI) for grapevine disease detection based on images

Nowadays, diseases are one of the major threats to sustainable viticulture. Manual detection through visual surveys, usually done by agronomists, relies on symptom identification and requires an enormous amount of time. Detection in field conditions remains difficult due to the lack of infrastructure to perform detailed and rapid field scouting covering the whole vineyard. In general, symptoms of grapevine diseases can be seen as spots and patterns on leaves. In this sense, computer vision technologies and artificial intelligence (AI) provide an excellent alternative to improve the current disease detection and quantification techniques using images of leaves and canopy. These novel methods can minimize the time spent on symptom detection, which helps in the control and quantification of the disease severity. In this article, we present some results of deep learning-based approaches used for detecting automatically leaves with downy mildew symptoms from RGB images acquired under laboratory and field conditions. The results obtained so far with AI approaches for detecting leaves with downy mildew symptoms are promising, and they put in evidence of the huge potential of these techniques for practical applications in the context of modern and sustainable viticulture

Postnatal exposure to mercury and neuropsychological development among preschooler children

The objective of this study was to describe the postnatal exposure to Hg and to evaluate its association with neuropsychological development among preschool children. The study population are 4–5 years old children (n = 1252) participant in the Spanish INMA Project. Total Hg was measured in cord blood and in hair samples taken at 4 years of age (2008–2012). Neuropsychological development was assessed using the McCarthy Scales of Children’s Abilities (MSCA). Information on covariates and possible confounders was obtained by questionnaires during pregnancy and childhood. Generalized additive and linear regression models were built in order to assess the relationship between MSCA scores and Hg exposure. We also evaluated the magnitude of the possible bias generated from measurement error in seafood intake estimate from questionnaire and Hg determination. The geometric mean of hair Hg was 0.98 μg/g [95% confidence interval (CI) 0.94, 1.03]. In the regression analysis, the association between Hg and the MSCA scores was positive for all the scales and statistically significant for the verbal (β = 0.89; 95%CI 0.38, 1.39), memory (β = 0.42; 95%CI 0.09, 0.76) and general cognitive scales (β = 1.35; 95%CI 0.45, 2.25). However, these associations were clearly attenuated when we adjusted by the children’s fish intake variables or when took into account theoretical scenarios of low precision in fish intake and Hg measurements. Hg levels in this Spanish population were high in comparison with other European countries; however, we did not observe adverse effects on child neuropsychological development associated with this postnatal exposure to Hg

Gualaceo: Su actividad económica

Licenciado en Ciencias de la Educación. Especialidad Historia y GeografíaCuenc

Apolo

CertamenTécnica: SoldaduraMateria-soporte: HierroFecha de ejecución: 1985La alusión clásica de la escultura demuestra su inspiración. Se ha resuelto con varillas de hierro soldadas marcando diferentes perfiles del cuerpo, para que el observador construya mentalmente volúmenes y masas de una figura corriendo. Dependiendo de la posición en que se coloque el espectador, podrá observar variados perfiles que el artista intencionadamente ha elegido para presentar la escultura

Abastecimiento de agua potable para la parroquia Checa

Abastecimiento de Agua Potable para la parroquia Checa información general; lugar geográfico, geología, crecimiento de la comunidad, levantamiento topográfico, análisis de aguas y tratamiento de la misma, análisis poblacional, consumo y demanda de agua en la zona, obras de captación, aducción, conducción, distribución y el cálculo de la red por el Método de Hardy Cross, finalmente tenemos desinfección, tanque de reserva y el diseño del acueducto sobre la Quebrada DispanIngeniero CivilCuenc