526 research outputs found

    Effect of restricted feeding under rearing on reproduction, body condition and blood metabolites of rabbit does selected for growth rate

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    [EN] Young rabbit females selected for growth rate can have nutritional needs which may not be met by the common practice of feed restriction during rearing in commercial rabbit production. The aim of this study was to analyse the effect of two different feeding programmes: restricted and ad libitum feeding, applied in young rabbit females for one month at the end of rearing, on reproductive performance, body condition and circulating metabolic hormones and metabolites in a rabbit line selected by growth rate in 3 consecutive reproductive cycles. Thus, twenty-four 16-week-old does were randomly assigned to a group in which the daily recommended nutrient intakes were satisfied (fed restricted: 130 g/day, n=13) or a group fed to satiety (ad libitum: 235.5 g/day, n=11) during one month. Then, all does were inseminated in 3 consecutive cycles using a 42-day reproductive cycle. Measurements of does’ body weight, perirenal fat thickness and plasma leptin, non-esterified-fatty-acids (NEFA), beta-hydroxybutyrate (BOHB) and fructosamine were performed at artificial insemination (AI), parturition and weaning time in 3 consecutive cycles. Reproductive performance of does was evaluated based on fertility, litter size at parturition, prolificacy and productivity. Differences in body weight were found only in the 1st cycle, ad libitum fed females being heavier than restricted ones. Nevertheless, body weight variances disappeared in later cycles. No differences were found in perirenal fat thickness. Finally, in ad libitum fed females slight differences were found in plasma levels of NEFAs (452 vs. 258 μekv/L and 527 vs. 306 μekv/L for 1st and 2nd cycles) and BOHB (0.26 vs. 0.03 mM for 2nd cycle), but disappeared in the 3rd reproductive cycle. Fertility, prolificacy and productivity was not significantly affected by the feeding programme. Nevertheless, total litter size showed to be higher in ad libitum fed females at second parturition (8.7 vs. 5.9 kits). Therefore, the evaluated feeding programmes until first AI in females selected by growth rate had no effect on their reproductive outcomes, as the global reproductive performance was not affected.This work was supported by the Spanish Research Project AGL2014- 53405-C2-1-P (CICYT). Carmen Naturil was supported by a research grant from the Education Ministry of the Valencian Regional Government (programme VALi+d. ACIF ⁄ 2013 ⁄ 296). English text version revised by N. Macowan English Language Service.Naturil-Alfonso, C.; Marco-Jiménez, F.; Pascual, J.; Vicente, J. (2017). Effect of restricted feeding under rearing on reproduction, body condition and blood metabolites of rabbit does selected for growth rate. World Rabbit Science. 25(4):303-312. https://doi.org/10.4995/wrs.2017.6848SWORD30331225

    Comportamiento de Astragalus Nitidiflorus bajo déficit hídrico

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    Life cycle assessment of earth-retaining walls: An environmental comparison

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    [EN] Earth-retaining walls are one of the most common structures in civil engineering, a discipline of the construction sector, which is known to produce one of the highest environmental impacts. Therefore, developing cleaner design and construction practices could contribute to a more sustainable future for our planet. To make a step towards this goal, this study comprises the life cycle assessment (LCA) of the four most common earth-retaining walls built between 1 to 6 m of height: cantilever walls, gravity walls, masonry walls and gabion walls to obtain the best solutions for the environment. To assess the environmental impacts caused throughout their whole life-cycle including the production, construction, use and end of life phases, we used the OpenLCA software, the ecoinvent 3.3 database and the ReCiPe (H) method. The associated uncertainties have been considered and the results are provided in both midpoint and endpoint approaches. Our findings show that gabion and masonry walls produce the lowest global impact. On the one hand, gabion walls cause less damage to human health but on the other hand, masonry walls cause less damage to the ecosystems. Furthermore, gravity walls produce similar impacts to gabion and masonry walls between 1 and 3 m of height as well as fewer impacts than cantilever walls for a height of 4 m. In conclusion, gabion and masonry walls are preferable to concrete walls for heights between 1 and 6 m and cantilever walls should be used over gravity walls for greater heights than 4.5 m.This research was funded by the Spanish Ministry of Economy and Competitiveness along with FEDER funding (Project BIA2017-85098-R).Pons, J.; Penadés-Plà, V.; Yepes, V.; Martí Albiñana, JV. (2018). Life cycle assessment of earth-retaining walls: An environmental comparison. Journal of Cleaner Production. 192:411-420. doi:10.1016/j.jclepro.2018.04.268S41142019

    Navier-Stokes transport coefficients of dd-dimensional granular binary mixtures at low density

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    The Navier-Stokes transport coefficients for binary mixtures of smooth inelastic hard disks or spheres under gravity are determined from the Boltzmann kinetic theory by application of the Chapman-Enskog method for states near the local homogeneous cooling state. It is shown that the Navier-Stokes transport coefficients are not affected by the presence of gravity. As in the elastic case, the transport coefficients of the mixture verify a set of coupled linear integral equations that are approximately solved by using the leading terms in a Sonine polynomial expansion. The results reported here extend previous calculations [V. Garz\'o and J. W. Dufty, Phys. Fluids {\bf 14}, 1476 (2002)] to an arbitrary number of dimensions. To check the accuracy of the Chapman-Enskog results, the inelastic Boltzmann equation is also numerically solved by means of the direct simulation Monte Carlo method to evaluate the diffusion and shear viscosity coefficients for hard disks. The comparison shows a good agreement over a wide range of values of the coefficients of restitution and the parameters of the mixture (masses and sizes).Comment: 6 figures, to be published in J. Stat. Phy

    Comparative assessment of RAMS and WRF short-term forecasts over Eastern Iberian Peninsula using various in-situ observations, remote sensing products and uncoupled land surface model datasets

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    The Regional Atmospheric Modeling System (RAMS) and the Weather Research and Forecasting (WRF) mesoscale models are being used for weather and air quality studies as well as forecasting tools in Numerical Weather Prediction (NWP) systems. In the current study, we perform a comparative assessment of these models under distinct typical atmospheric conditions, classified according to the dominant wind flow and cloudiness, over Eastern Iberian Peninsula. This study is focused on the model representation of key physical processes in terms of meteorology and surface variables during a 7-days period in summer 2011. The hourly outputs produced by these two models are compared not only with observed standard surface variables, measured at different permanent weather stations located over the region of study, but also with different surface remote sensing products and uncoupled Land Surface Models (LSM) datasets. Confronting RAMS and WRF, the current study highlights relevant differences over areas near the coast when mesoscale circulations or Eastern synoptic advections are developed over the region of study. A higher moisture content is observed under these atmospheric conditions, due to the moisture transport by the sea breeze inland. In this regard, it has been found that the Eastern wind field simulated by WRF reaches inland areas and comprises a larger sea breeze extension than RAMS. This sea breeze development impacts meteorology and surface variables in locations not too close to the coast, but still affected by land-sea winds. Additionally, WRF remains more windy and moister than RAMS at night-time, while alike results are found under Western synoptic advections. The results obtained in the current paper show differences under distinct dominant atmospheric conditions, which outline further research in this field in order to achieve more general conclusions

    El cuento como entorno de crecimiento sociopersonal en la intervención psicopedagógica con población adolescente infractora

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    Este estudio pretende valorar la utilidad del escenario relacional introspectivo y de aprendizaje vinculado al espacio de cuentacuentos, analizando su naturaleza simbólica y emocional desde la perspectiva de la población adolescente infractora participante. La población educanda, bajo medida judicial de privación de libertad, ha participado en el proceso a través de los cuentos y de la evocación que éstos les provocaban, de tal forma que, mediante textos producidos oralmente y por escrito, han acotado un sistema categorial inductivo conformado por once variables diferenciadas. Éstas siguen un itinerario de afrontamiento, de aprendizaje y, en su caso, de apropiación y autonomía. La investigación se ha desarrollado con metodología cualitativa, haciendo uso del método de la grounded theory para el análisis de los datos. Se ha garantizado la triangulación intertécnicas (cuestionario sociodemográfico, entrevistas y focus-group) e intersujetos participantes

    Identification of electroactive sites in Prussian Yellow films

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    Prussian Blue films were electrogenerated on the surface of the transparent ITO electrodes. The electrochemical oxidation to the Prussian Yellow form was investigated by means of in situ voltammetry and vis–NIR spectroscopic techniques. Changes of the whole spectra between 400 and 950 nm were analyzed and three characteristic wavelengths were selected to in situ follow the electrochemical changes of the films. Voltammetric peaks and absorbance derivative curves at these three wavelengths were deconvoluted and were interpreted such as the overlapping of different electrochemical processes. The correlation between these overlapped processes has allowed proposing three different electrochemical processes for the interpretation of the whole electrochemical response. One of these processes corresponds to the oxidation of View the MathML source units where the electrical charge is balanced by the exchange of neighbor potassium cations. The second one is associated to the oxidation of View the MathML source trapped sites and the third one also to the oxidation of View the MathML source units but in this last case, the absence of neighbor potassium cations causes that the electrical charge balance takes place by the exchange of some anions such as the chloride. These processes have been identified on the basis of previous results and on the interesting information provided by the coupling voltammetry and absorbance derivative curves at these characteristic wavelengths

    Diffusion of impurities in a granular gas

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    Diffusion of impurities in a granular gas undergoing homogeneous cooling state is studied. The results are obtained by solving the Boltzmann--Lorentz equation by means of the Chapman--Enskog method. In the first order in the density gradient of impurities, the diffusion coefficient DD is determined as the solution of a linear integral equation which is approximately solved by making an expansion in Sonine polynomials. In this paper, we evaluate DD up to the second order in the Sonine expansion and get explicit expressions for DD in terms of the restitution coefficients for the impurity--gas and gas--gas collisions as well as the ratios of mass and particle sizes. To check the reliability of the Sonine polynomial solution, analytical results are compared with those obtained from numerical solutions of the Boltzmann equation by means of the direct simulation Monte Carlo (DSMC) method. In the simulations, the diffusion coefficient is measured via the mean square displacement of impurities. The comparison between theory and simulation shows in general an excellent agreement, except for the cases in which the gas particles are much heavier and/or much larger than impurities. In theses cases, the second Sonine approximation to DD improves significantly the qualitative predictions made from the first Sonine approximation. A discussion on the convergence of the Sonine polynomial expansion is also carried out.Comment: 9 figures. to appear in Phys. Rev.

    The electronics of the energy plane of the NEXT-White detector

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    [EN] This paper describes the electronics of NEXT-White (NEW) detector PMT plane, a high pressure xenon TPC with electroluminescent amplification (HPXe-EL) currently operating at the Laboratorio Subterraneo de Canfranc (LSC) in Huesca, Spain. In NEXT-White the energy of the event is measured by a plane of photomultipliers (PMTs) located behind a transparent cathode. The PMTs are Hamamatsu R11410-10 chosen due to their low radioactivity. The electronics have been designed and implemented to fulfill strict requirements: an overall energy resolution below 1% and a radiopurity budget of 20 mBq unit(-1) in the chain of Bi-214. All the components and materials have been carefully screened to assure a low radioactivity level and at the same time meet the required front-end electronics specifications. In order to reduce low frequency noise effects and enhance detector safety a grounded cathode connection has been used for the PMTs. This implies an AC-coupled readout and baseline variations in the PMT signals. A detailed description of the electronics and a novel approach based on a digital baseline restoration to obtain a linear response and handle AC coupling effects is presented. The final PMT channel design has been characterized with linearity better than 0.4% and noise below 0.4mV.We acknowledge support from the following agencies and institutions: the European Research Council (ERC), Spain under the Advanced Grant 339787-NEXT; the Ministerio de Economia y Competitividad of Spain under grants FIS2014-53371-C04, the Severo Ochoa Program, Spain SEV-2014-0398 and the Maria de Maetzu Program, Spain MDM-2016-0692; the GVA of Spain under grants PROMETEO/2016/120 and SEJI/2017/011; the Portuguese FCT and FEDER, Spain through the program COMPETE, projects PTDC/FIS-NUC/2525/2014 and UID/FIS/04559/2013; the U.S. Department of Energy under contracts number DE-AC02-07CH11359 (Fermi National Accelerator Laboratory), DE-FG02-13ER42020 (Texas A&M) and de-sc0017721 (University of Texas at Arlington); and the University of Texas at Arlington. We acknowledge partial support from the European Union Horizon 2020 research and innovation programme, Spain under the Marie Sklodowska-Curie grant agreements No. 690575 and 674896. We also warmly acknowledge the Laboratorio Nazionale di Gran Sasso (LNGS) and the Dark Side collaboration for their help with TPB coating of various parts of the NEXT-White TPC. Finally, we are grateful to the Laboratorio Subterraneo de Canfranc for hosting and supporting the NEXT experiment.Álvarez-Puerta, V.; Herrero Bosch, V.; Esteve Bosch, R.; Laing, A.; Rodriguez-Samaniego, J.; Querol-Segura, M.; Monrabal, F.... (2019). The electronics of the energy plane of the NEXT-White detector. Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment. 917:68-76. https://doi.org/10.1016/j.nima.2018.11.126S687691
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