7,909 research outputs found

    Acceleration of the Surface Test Integral Using Vertex Functions

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    In recent years, many papers have reported on the efficient and accurate evaluation of the double surface integrals that arise in the Method of Moments. Most have focused on the careful evaluation of the inner integral and assumed that the outer integral is sufficiently smooth to be easily evaluated numerically. More recently, several papers have appeared where the double integral is treated as a whole using the divergence theorem. These papers show promising results, though their implementation may imply changes to the integration paradigm for the associated codes. Here, instead, we investigate a technique that improves the numerical evaluation of the test integral without affecting the treatment of the source integral. From the integrand of the outer integral, we subtract pairs of quasi-static, so-called vertex functions defined on the source triangle. The approach is compared to standard Gauss-triangle schemes to demonstrate its effectiveness

    6-D MoM Reaction Integrals Evaluated via the Divergence Theorem

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    In this contribution we propose an accurate and efficient numerical evaluation of 6-D reaction integrals that appear in the Method of Moment (MoM) discretization of Volume Integral Equations (VIEs)

    Evaluation of Static Potential Integrals on Triangular Domains

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    Static potential integrals for constant and linear sources on triangles are derived in a straightforward way. The new representations, as presented, are robust with respect to machine evaluation in important limiting cases. The potential integrals comprise up to six functions, each dependent on the relative position and orientation (with respect to an observation point) of a vertex and edge, respectively, of the source triangle. Gradients of the potentials are derived by differentiation, thus preserving relations between the representations. Each such vertex function reveals any anomalous functional behavior near its associated vertex or edge, which is useful information for devising test integral schemes. Potential plots in the source plane of an equilateral triangle illustrate such behavior, as do similar plots for each vertex function and gradient components near their associated edge and vertex

    Parenting behaviors of mothers and fathers of young children with intellectual disability evaluated in a natural context

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    The aims of this study were to analyze the interactions of mothers and fathers with their children with intellectual disabilities, focusing on certain parental behaviors previously identified as promoting child development, and to explore the relations between parenting and some sociodemographic variables. A sample of 87 pairs of mothers and fathers of the same children were recruited from Early Intervention Centers. The children (58 male and 29 female) were aged 20–47 months. Most of the families (92%) were from the province of Barcelona(Spain), and the remaining 8% were from the other provinces of Catalonia (Spain). Parenting behaviors, divided into four domains (Affection, Responsiveness, Encouragement, and Teaching) were assessed from self-recorded videotapes, in accordance with the validated Spanish version of the PICCOLO (Parenting Interactions with Children: Checklist of Observations Linked to Outcomes). Parents were administered a sociodemographic questionnaire. The results revealed strong similarities between mothers’ and fathers’ parental behaviors. Mothers and fathers were more likely to engage in affectionate behavior than in teaching behavior. Only maternal teaching presented a significant positive relation to the child’s age. With respect to the child’s gender, no differences were observed in mothers’ parenting. Conversely, fathers scored significantly higher in Responsiveness, Encouragement and Teaching (and had higher total parenting scores) when interacting with boys. The severity of the child’s ID had a statistically significant effect only on fathers’ Teaching, which showed lower mean scores in the severe ID group than in the moderate and mild ID groups. Teaching also presented a significant positive relation to mother’s age, but father’s age was not related to any parenting domain (...)This research was supported by a grant from the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund (Project PSI2015-63627-R). All authors were members of the project teams. We appreciate the financial aid from the University of Barcelona and the University of Malaga for publishing open access. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Reducing the Dimensionality of 6-D MoM Integrals Applying Twice the Divergence Theorem

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    In this paper we propose a scheme for evaluating the 6-D interaction integrals appearing in volume integral equation solved with the Method of Moments and tetrahedral elements. We treat as a whole the double volume integral, applying the divergence theorem first on the source domain and then on the test domain. With the proper variable transformation and reordering, the 6-D integrals are expressed as two radial integrals plus four linear integrals over the source and observation domain planes

    The ‘Palo a Pique’ Long-Term Research Platform: First 25 years of a Crop-Livestock Experiment in Uruguay

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    Mixed crop-livestock long-term experiments (LTE) are critical to increase the understanding of sustainability in complex agroecosystems. One example is the ‘Palo a Pique’ LTE which has been running for 25 years in Uruguay (1995 to present) evaluating four pasture-crop rotations under livestock grazing with no-till technology in soils with severe limitations. Results demonstrate that cropping systems reduced soil organic carbon (SOC) compared with permanent pastures, and that perennial pastures rotating with crops were critical to mitigate SOC losses. Data from the ‘Palo a Pique’ LTE has contributed to establish new national policies to secure sustainability of agricultural-based systems. Although the original purpose of the LTE was oriented to crops and soils, a demand for sustainable livestock intensification has gathered momentum over recent years. As a result, the current approach of the ‘Palo a Pique’ LTE matches each pasture-crop rotation with the most suitable livestock strategy with the common goal of producing 400 kg liveweight/ha per year. General approaches to the pursuit of sustainable livestock intensification include: shortening the cycle of production, diversifying animal categories, increasing liveweight gain and final animal liveweight, and strategic livestock supplementation. Prediction of trade-offs between environmental, economic, and production indicators can be addressed through monitoring and modelling, enabling timely anticipation of adverse sustainability issues on commercial farms. The ‘Palo a Pique’ LTE serves as a framework to address contemporary and future questions dealing with the role of ruminants on climate change, competition for land, nutrient dynamics, and food security

    Gestational hypothyroxinemia affects its offspring with a reduced suppressive capacity impairing the outcome of the experimental autoimmune encephalomyelitis

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    Indexación: Scopus.Hypothyroxinemia (Hpx) is a thyroid hormone deficiency (THD) condition highly frequent during pregnancy, which although asymptomatic for the mother, it can impair the cognitive function of the offspring. Previous studies have shown that maternal hypothyroidism increases the severity of experimental autoimmune encephalomyelitis (EAE), an autoimmune disease model for multiple sclerosis (MS). Here, we analyzed the immune response after EAE induction in the adult offspring gestated in Hpx. Mice gestated in Hpx showed an early appearance of EAE symptoms and the increase of all parameters of the disease such as: the pathological score, spinal cord demyelination, and immune cell infiltration in comparison to the adult offspring gestated in euthyroidism. Isolated CD4+CD25+ T cells from spleen of the offspring gestated in Hpx that suffer EAE showed reduced capacity to suppress proliferation of effector T cells (TEff) after being stimulated with anti-CD3 and anti-CD28 antibodies. Moreover, adoptive transfer experiments of CD4+CD25+ T cells from the offspring gestated in Hpx suffering EAE to mice that were induced with EAE showed that the receptor mice suffer more intense EAE pathological score. Even though, no significant differences were detected in the frequency of Treg cells and IL-10 content in the blood, spleen, and brain between mice gestated in Hpx or euthyroidism, T cells CD4+CD25+ from spleen have reduced capacity to differentiate in vitro to Treg and to produce IL-10. Thus, our data support the notion that maternal Hpx can imprint the immune response of the offspring suffering EAE probably due to a reduced capacity to trigger suppression. Such "imprints" on the immune system could contribute to explaining as to why adult offspring gestated in Hpx suffer earlier and more intense EAE. © 2018 Haensgen, Albornoz, Opazo, Bugueño, Jara Fernández, Binzberger, Rivero-Castillo, Venegas Salas, Simon, Cabello-Verrugio, Elorza, Kalergis, Bueno and Riedel.https://www.frontiersin.org/articles/10.3389/fimmu.2018.01257/ful
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