316 research outputs found

    Efecto de la aplicación foliar de selenio y zinc para aumentar los rendimientos cuantitativos y cualitativos de colza en diferentes fechas de siembra

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    The sowing date is an important factor for expanding the cultivated area of rapeseed and affects seed yield, oil content, and fatty acid compounds. Micronutrient elements play an important role in improving the vegetative and reproductive growth of the plant, especially under conditions of biological and environmental stresses. A two-year experiment (2014-2016) was performed to study the response of rapeseed genotypes to foliar application of micronutrients on different sowing dates. The treatments were arranged as a factorial-split plot in a randomized complete block design with three replicates. Three sowing dates of 7 (well-timed sowing date), 17, and 27 (delayed sowing dates) October and two levels of foliar application with pure water (control), selenium (1.5%), zinc (1.5%), and selenium+zinc (1.5%) were factorial in the main plots and five genotypes of SW102, Ahmadi, GKH2624, GK-Gabriella, and Okapi were randomized in the subplots (a total of 30 treatments). Seed yield, oil yield and content, oleic acid, and linoleic acid were reduced when rapeseeds were cultivated on 17 and 27 October, while the contents in palmitic, linolenic, and erucic acids, and glucosinolate increased (p < 0.01). a selenium+zinc treatment improved seed yield, oil content and yield (p < 0.01). The oil quality increased due to increased contents of oleic and linoleic acids under the selenium+zinc treatment (p < 0.01). The GK-Gabriella and GKH2624 genotypes are recommended to be sown on well-timed (7 October) and delayed sowing dates (17 and 27 October) and treated with selenium+zinc due to the higher oil yield, linoleic and oleic acids.La fecha de siembra es un factor importante para expandir el área cultivada de colza que afecta el rendimiento de la semilla, el contenido de aceite y la composición en ácidos grasos. Los micronutrientes juegan un papel importante en la mejora del crecimiento vegetativo y reproductivo de la planta, especialmente en condiciones de estrés biológico y ambiental. Se realizó un experimento de dos años (2014-2016) para estudiar la respuesta de los genotipos de colza a la aplicación foliar de micronutrientes en diferentes fechas de siembra. Los tratamientos se organizaron como una parcela dividida factorial en un diseño de bloques completos al azar con tres repeticiones. Tres fechas de siembra del 7 (fecha de siembra en el momento oportuno), 17 y 27 (fechas de siembra retrasadas) de octubre y dos niveles de aplicación foliar con agua pura (control), selenio (1,5%), zinc (1,5%) y selenio + zinc (1.5%) fueron factoriales en las parcelas principales y cinco genotipos de SW102, Ahmadi, GKH2624, GK-Gabriella y Okapi fueron aleatorizados en las subparcelas (un total de 30 tratamientos). El rendimiento de semilla, el contenido y rendimiento de aceite, los ácidos grasos oleico y linoleico se redujeron cuando se cultivaron semillas de colza los días 17 y 27 de octubre, mientras que los contenidos de los ácidos grasos palmítico, linolénico y erúcico y glucosinolato aumentaron (p <0,01). El tratamiento con selenio + zinc mejoró el rendimiento de semillas, el contenido de aceite y el rendimiento (p <0,01). La calidad del aceite aumentó debido al mayor contenido de ácidos oleico y linoleico bajo tratamiento con selenio + zinc (p <0.01). Se recomiendan los genotipos GK-Gabriella y GKH2624 sembrados en fechas oportunas (7 de octubre) y tardía (17 y 27 de octubre) y tratados con selenio + zinc, respectivamente, debido al mayor rendimiento de aceite y contenido de los ácidos linoleico y oleico

    Fatigue analysis-based numerical design of stamping tools made of cast iron

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    This work concerns stress and fatigue analysis of stamping tools made of cast iron with an essentially pearlitic matrix and containing foundry defects. Our approach consists at first, in coupling the stamping numerical processing simulations and structure analysis in order to improve the tool stiffness geometry for minimizing the stress state and optimizing their fatigue lifetime. The method consists in simulating the stamping process by considering the tool as a perfect rigid body. The estimated contact pressure is then used as boundary condition for FEM structure loading analysis of the tool. The result of this analysis is compared with the critical stress limit depending on the automotive model. The acceptance of this test allows calculating the fatigue lifetime of the critical zone by using the S–N curve of corresponding load ratio. If the prescribed tool life requirements are not satisfied, then the critical region of the tool is redesigned and the whole simulation procedures are reactivated. This method is applied for a cast iron EN-GJS-600-3. The stress-failure (S–N) curves for this material is determined at room temperature under push pull loading with different load ratios R0σmin/σmax0−2, R0−1 and R00.1. The effects of the foundry defects are determined by SEM observations of crack initiation sites. Their presence in tested specimens is associated with a reduction of fatigue lifetime by a factor of 2. However, the effect of the load ratio is more important

    Portland cement pastes analysed by synchrotron and laboratory X-ray imaging

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    Portland Cement (PC) is the most used construction material and the derived building materials have very complex hierarchical microstructures. Quantitative characterization of their microstructures is of paramount importance for assessing the performance and durability of the final products. As cement performance is controlled by its phase composition and microstructure, in particular, the pore network plays a critical role in the mechanical properties and durability. The chemical and hydration changes in PC binders affect their performances mainly because of the binding properties of the main component, the so-called C-S-H gel. Here, we analyse porosity in PC pastes using laboratory and synchrotron X-ray micro-tomography with different water to cement mass ratios (w/c) after 28 days of hydration. Monochromatic synchrotron X-ray microtomography is used for reference and the main aim is determining volume percentage of different components with focus on porosity. It will be shown, as expected, that higher amount of water (that increases fluidity of pastes) results in higher porosities at 28 days of hydration. Therefore, in the histogram and tomograms more pores, hydrated materials, and less anhydrous materials would appear with increasing w/c (see Figure 1). The excellent spatial resolution (and slightly better contrast) of synchrotron experiments serve as reference for data analysis. Despite 0.2-0.3 m voxel-sizes in all the used experimental setups (see Figure 2), the laboratory tomograms show some limitations that will be discussed. In this work, a two-steps approach is followed. Firstly, we will report the analysis of the histograms by classifying in the three types of components based on grey-levels: i) pores, ii) hydrated components; and iii) unreacted cement phases. Secondly, segmented pore contribution will be further analyzed and the results from laboratory tomograms will be compared with the reference values derived from synchrotron data.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Comparing the Efficacy of Tolterodine and Gabapentin Versus Placebo in Catheter Related Bladder Discomfort after Percutaneous Nephrolithotomy: A Randomized Clinical Trial

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    Purpose: The purpose of this study was to compare the efficacy of tolterodine and gabapentin vs placebo in catheter related bladder discomfort (CRBD) following percutaneous nephrolithotomy (PCNL). Materials and Methods: This study was a double-blind parallel group randomized clinical trial. Patients who were candidates of PCNL were enrolled. Patients were randomized to treatment groups of tolterodine 2 mg orally (PO) (group T, n = 50), gabapentin 600 mg PO (group G, n = 50), and placebo (group P, n = 70) 1 hour before operation using balanced block randomization. The primary endpoint of interest was visual analog pain scale in 1, 3, 12, and 24 hours after the operation. Secondary endpoints included rescue analgesic use (opioid and nonopioid). Results: The frequency of severe CRBD in 1,12, and 24 hours after the operation was 4, 4, and 6 in group T vs 4, 0, and 2 in group G vs 47, 14, and 6 in the P group (p < 0.001). The number of paracetamol injections for CRBD in the T and G groups was significantly lower than the placebo group (1.8 ± 0.8 vs 1.8 ± 0.7 vs 3.6 ± 0.7, p < 0.001). Likewise the number of pethidine injections in the T and G groups was significantly lower than the placebo group (0.42 ± 0.54 vs 0.68 ± 0.62 vs 2.4 ± 0.64, p < 0.001). In patients with history of Double-J insertion, the severity of CRBD was lower in all treatment groups. Conclusions: Preoperative administration of oral tolterodine or gabapentin reduces postoperative CRBD and the need for rescue analgesics as much as 24 hours after surgery. Patients with history of Double-J insertion experience less CRBD. © Copyright 2018, Mary Ann Liebert, Inc

    Comparing the Efficacy of Tolterodine and Gabapentin Versus Placebo in Catheter Related Bladder Discomfort after Percutaneous Nephrolithotomy: A Randomized Clinical Trial

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    Purpose: The purpose of this study was to compare the efficacy of tolterodine and gabapentin vs placebo in catheter related bladder discomfort (CRBD) following percutaneous nephrolithotomy (PCNL). Materials and Methods: This study was a double-blind parallel group randomized clinical trial. Patients who were candidates of PCNL were enrolled. Patients were randomized to treatment groups of tolterodine 2 mg orally (PO) (group T, n = 50), gabapentin 600 mg PO (group G, n = 50), and placebo (group P, n = 70) 1 hour before operation using balanced block randomization. The primary endpoint of interest was visual analog pain scale in 1, 3, 12, and 24 hours after the operation. Secondary endpoints included rescue analgesic use (opioid and nonopioid). Results: The frequency of severe CRBD in 1,12, and 24 hours after the operation was 4, 4, and 6 in group T vs 4, 0, and 2 in group G vs 47, 14, and 6 in the P group (p < 0.001). The number of paracetamol injections for CRBD in the T and G groups was significantly lower than the placebo group (1.8 ± 0.8 vs 1.8 ± 0.7 vs 3.6 ± 0.7, p < 0.001). Likewise the number of pethidine injections in the T and G groups was significantly lower than the placebo group (0.42 ± 0.54 vs 0.68 ± 0.62 vs 2.4 ± 0.64, p < 0.001). In patients with history of Double-J insertion, the severity of CRBD was lower in all treatment groups. Conclusions: Preoperative administration of oral tolterodine or gabapentin reduces postoperative CRBD and the need for rescue analgesics as much as 24 hours after surgery. Patients with history of Double-J insertion experience less CRBD. © Copyright 2018, Mary Ann Liebert, Inc

    Men, maternity and moral residue:negotiating the moral demands of the transition to first time fatherhood

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    This article discusses men's transition to first time fatherhood, with a focus on the way they recognise various in-tension moral demands and negotiate an appropriate role for themselves. The findings are taken from a longitudinal study, drawing on elements of grounded theory, comprising a series of face-to-face and telephone interviews with 11 men over a 9-month period from the 12(th) week of pregnancy to 8 weeks after the birth. The analysis focuses on men's feelings and experience of exclusion and participation, and their response and reaction to that experience. The findings present two descriptive themes, ‘on the inside looking in’ and ‘present but not participating’, followed by third theme ‘deference and support: a moral response’ that exposes the dilemmatic nature of men's experience and explains the participants’ apparent acceptance of being less involved. The discussion explores the concept of moral residue, arguing that while deference and support may be an appropriate role for fathers in the perinatal period it may also be a compromise that leads to feelings of uncertainty and frustration, which is a consequence of being in a genuinely dilemmatic situation

    Myocardial Fat Imaging

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    The presence of intramyocardial fat may form a substrate for arrhythmias, and fibrofatty infiltration of the myocardium has been shown to be associated with sudden death. Therefore, noninvasive detection could have high prognostic value. Fat-water–separated imaging in the heart by MRI is a sensitive means of detecting intramyocardial fat and characterizing fibrofatty infiltration. It is also useful in characterizing fatty tumors and delineating epicardial and/or pericardial fat. Multi-echo methods for fat and water separation provide a sensitive means of detecting small concentrations of fat with positive contrast and have a number of advantages over conventional chemical-shift fat suppression. Furthermore, fat and water–separated imaging is useful in resolving artifacts that may arise due to the presence of fat. Examples of fat-water–separated imaging of the heart are presented for patients with ischemic and nonischemic cardiomyopathies, as well as general tissue classification

    A nonlinear Lagrangian particle model for grains assemblies including grain relative rotations

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    International audienceWe formulate a discrete Lagrangian model for a set of interacting grains, which is purely elastic. The considered degrees of freedom for each grain include placement of barycenter and rotation. Further, we limit the study to the case of planar systems. A representative grain radius is introduced to express the deformation energy to be associated to relative displacements and rotations of interacting grains. We distinguish inter‐grains elongation/compression energy from inter‐grains shear and rotations energies, and we consider an exact finite kinematics in which grain rotations are independent of grain displacements. The equilibrium configurations of the grain assembly are calculated by minimization of deformation energy for selected imposed displacements and rotations at the boundaries. Behaviours of grain assemblies arranged in regular patterns, without and with defects, and similar mechanical properties are simulated. The values of shear, rotation, and compression elastic moduli are varied to investigate the shapes and thicknesses of the layers where deformation energy, relative displacement, and rotations are concentrated. It is found that these concentration bands are close to the boundaries and in correspondence of grain voids. The obtained results question the possibility of introducing a first gradient continuum models for granular media and justify the development of both numerical and theoretical methods for including frictional, plasticity, and damage phenomena in the proposed model

    Cardiomyocyte Specific Ablation of p53 Is Not Sufficient to Block Doxorubicin Induced Cardiac Fibrosis and Associated Cytoskeletal Changes

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    Doxorubicin (Dox) is an anthracycline used to effectively treat several forms of cancer. Unfortunately, the use of Dox is limited due to its association with cardiovascular complications which are manifested as acute and chronic cardiotoxicity. The pathophysiological mechanism of Dox induced cardiotoxicity appears to involve increased expression of the tumor suppressor protein p53 in cardiomyocytes, followed by cellular apoptosis. It is not known whether downregulation of p53 expression in cardiomyocytes would result in decreased rates of myocardial fibrosis which occurs in response to cardiomyocyte loss. Further, it is not known whether Dox can induce perivascular necrosis and associated fibrosis in the heart. In this study we measured the effects of acute Dox treatment on myocardial and perivascular apoptosis and fibrosis in a conditional knockout (CKO) mouse model system which harbours inactive p53 alleles specifically in cardiomyocytes. CKO mice treated with a single dose of Dox (20 mg/kg), did not display lower levels of myocardial apoptosis or reactive oxygen and nitrogen species (ROS/RNS) compared to control mice with intact p53 alleles. Interestingly, CKO mice also displayed higher levels of interstitial and perivascular fibrosis compared to controls 3 or 7 days after Dox treatment. Additionally, the decrease in levels of the microtubule protein α-tubulin, which occurs in response to Dox treatment, was not prevented in CKO mice. Overall, these results indicate that selective loss of p53 in cardiomyocytes is not sufficient to prevent Dox induced myocardial ROS/RNS generation, apoptosis, interstitial fibrosis and perivascular fibrosis. Further, these results support a role for p53 independent apoptotic pathways leading to Dox induced myocardial damage and highlight the importance of vascular lesions in Dox induced cardiotoxicity
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