509 research outputs found

    Nonlinear field theories during homogeneous spatial dilation

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    The effect of a uniform dilation of space on stochastically driven nonlinear field theories is examined. This theoretical question serves as a model problem for examining the properties of nonlinear field theories embedded in expanding Euclidean Friedmann-Lema\^{\i}tre-Robertson-Walker metrics in the context of cosmology, as well as different systems in the disciplines of statistical mechanics and condensed matter physics. Field theories are characterized by the speed at which they propagate correlations within themselves. We show that for linear field theories correlations stop propagating if and only if the speed at which the space dilates is higher than the speed at which correlations propagate. The situation is in general different for nonlinear field theories. In this case correlations might stop propagating even if the velocity at which space dilates is lower than the velocity at which correlations propagate. In particular, these results imply that it is not possible to characterize the dynamics of a nonlinear field theory during homogeneous spatial dilation {\it a priori}. We illustrate our findings with the nonlinear Kardar-Parisi-Zhang equation

    Unraveling the Molecular Determinants of Manual Therapy: An Approach to Integrative Therapeutics for the Treatment of Fibromyalgia and Chronic Fatigue Syndrome/Myalgic Encephalomyelitis

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    Application of protocols without parameter standardization and appropriate controls has led manual therapy (MT) and other physiotherapy-based approaches to controversial outcomes. Thus, there is an urgency to carefully define standard protocols that elevate physiotherapy treatments to rigorous scientific demands. One way in which this can be achieved is by studying gene expression and physiological changes that associate to particular, parameter-controlled, treatments in animal models, and translating this knowledge to properly designed, objective, quantitatively-monitored clinical trials (CTs). Here, we propose a molecular physiotherapy approach (MPTA) requiring multidisciplinary teams, to uncover the scientific reasons behind the numerous reports that historically attribute health benefits to MT-treatments. The review focuses on the identification of MT-induced physiological and molecular responses that could be used for the treatment of fibromyalgia (FM) and chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME). The systemic effects associated to mechanical-load responses are considered of particular relevance, as they suggest that defined, low-pain anatomic areas can be selected for MT treatment and yet yield overall benefits, an aspect that might result in it being essential to treat FM. Additionally, MT can provide muscle conditioning to sedentary patients without demanding strenuous physical effort, which is particularly detrimental for CFS/ME patients, placing MT as a real option for integrative medicine programs to improve FM and CFS/ME.This research was funded by the Fundación Universidad Católica de Valencia San Vicente Mártir (UCV) Research Grant Program grant number 2018-121-001.Fisioterapi

    The short term influence of aboveground biomass cover crops on C sequestration and β-glucosidase in a vineyard ground under semiarid conditions

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    © 2014 Ministerio de Agricultura Pesca y Alimentacion. All Rights Reserved. Tillage and semiarid Mediterranean climatic conditions accelerate soil organic matter losses in Spanish vineyards. Previous studies showed that cover crops can increase soil organic carbon (SOC) in Mediterranean vineyards. The objectives of this study were to evaluate the influence of two different cover crops in the short term on soil C sequestration in a semiarid vineyard and to study the potential use of both β-glucosidase enzimatic activity (GLU) and the GLU/SOC ratio in order to assess the SOC increase. The experiment was carried out in a cv. Tempranillo (Vitis vinifera L.) vineyard on a Oxyaquic Xerorthent soil in Rioja winegrowing region (NE, Spain). The experimental design was established in 2009 with three treatments: conventional tillage; sown barley cover crop (Hordeum vulgare, L.); sown Persian clover cover crop (Trifolium resupinatum L.). Carbon in the aboveground biomass with each cover crop was monitored. Soil was sampled in June 2011 and June 2012, and SOC, GLU and the GLU/SOC ratio were determined. After 3 years both cover crops increased SOC at soil surface with C sequestration rates of 0.47 and 1.19 t C ha–1 yr–1 for BV and CV respectively. GLU and GLU/SOC ratio increased in both cover crops at 0-5 cm soil depth. The C sequestration rates and GLU were related to the cover crops aboveground biomass. In consequence, in semiarid vineyards under cover crops GLU could be an appropriate indicator to asses the increase of SOC and the soil quality improvement in the short-term (2-3 years).This study was supported by the Spanish Ministry of Science, INIA and European Social Fund through project INIA-RTA 2009-00101-00-00. F. Peregrina thanks the INIA (Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria) and European Social Fund for its post-doctoral grants and E. Pérez-Álvarez thanks the INIA for her pre-doctoral grant.Peer Reviewe

    Deshojado precoz en Viura y Malvasía riojana

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    En este trabajo se ha estudiado la aplicación de deshojado precoz en las variedades blancas Viura y Malvasía riojana como herramienta para el control del rendimiento y la mejora de la sanidad de la uva, con el objetivo de incrementar la calidad de sus vinos. Estas variedades presentan una producción elevada y racimos de gran tamaño, muy compactos, por lo que son bastante sensibles a Botrytis cinerea. Los resultados obtenidos indican que esta práctica puede plantearse como un método eficaz para el control del rendimiento y la mejora del estado sanitario de la uva; asimismo, favorece una correcta evolución del proceso de maduración, mejorando la composición de la uva debido al incremento del contenido de sólidos solubles y de compuestos fenólicos. La disminución de la acidez total y el aumento de pH que se producen en la uva, debido a la modificación del microclima de los racimos y al control del rendimiento, podría considerarse un inconveniente a tener en cuenta, sobre todo en el caso de variedades blancas que se caracterizan por un déficit de acidez total.Peer Reviewe

    Robust Fuzzy Clustering via Trimming and Constraints

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    Producción CientíficaA methodology for robust fuzzy clustering is proposed. This methodology can be widely applied in very different statistical problems given that it is based on probability likelihoods. Robustness is achieved by trimming a fixed proportion of “most outlying” observations which are indeed self-determined by the data set at hand. Constraints on the clusters’ scatters are also needed to get mathematically well-defined problems and to avoid the detection of non-interesting spurious clusters. The main lines for computationally feasible algorithms are provided and some simple guidelines about how to choose tuning parameters are briefly outlined. The proposed methodology is illustrated through two applications. The first one is aimed at heterogeneously clustering under multivariate normal assumptions and the second one migh be useful in fuzzy clusterwise linear regression problems.Ministerio de Economía, Industria y Competitividad (MTM2014-56235-C2-1-P)Junta de Castilla y León (programa de apoyo a proyectos de investigación – Ref. VA212U13

    Amino acids content in 'Tempranillo' must from three soil types over four vintages

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    Amino acids are the main grape nitrogen compounds and the principal source of N for yeasts, being precursors of several volatile compounds. Therefore, N compound concentrations in musts can affect sensorial characteristics of wines. The aim of this study was to analyse the influence of N-NO3- and N-NH4+ contents from different soils on profile and content of amino acids in 'Tempranillo' grapes. In order to determine this soil influence on must quality, three plots were selected in AOC Rioja, classified as Fluventic Haploxerepts, Typic Calcixerepts, and Petrocalcic Palexerolls. The results showed that amino acids and yeast assimilable nitrogen (YAN) content allowed us to differentiate samples from the three soils, and in each soil type, samples of each season. In general, must contents of total amino acids and some of them, as alanine, threonine, and tyrosine, were more influenced by soil type; YAN, proline, histidine, serine, and glycine concentrations mainly depended on the interaction soil-vintage. In conclusion, free amino acids concentration could be a tool to differentiate musts coming from different soils
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