292 research outputs found

    Effects of magnesium on the structure of aluminoborosilicate glasses: NMR assessment of interatomic potentials models for molecular dynamics

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    Classical molecular dynamics simulations have been used to investigate the structural role of Mg and its effect when it is incorporated in sodium aluminoborosilicate glasses. The simulations have been performed using three interatomic potentials; one is based on the rigid ionic model parameterized by Wang et al. (2018) and two slightly different parameterization of the core-shell model provided by Stevensson et al. (2018) and Pedone et al. (2020) The accuracies of these models have been assessed by detailed structural analysis and comparing the simulated nuclear magnetic resonance (NMR) spectra for spin active nuclei (Si-29, Al-27, B-11, O-17, Mg-25, and Na-23) with the experimental counterparts collected in a previous work. Our simulations reveal that the core-shell parameterizations provide better structural models. In fact, they better reproduce the NMR spectra of all the investigated nuclei and give better agreement with known experimental data. Magnesium is found to be five coordinated on average with distances with oxygen in between a network modifier (like Na) and an intermediate network formed (like Al). It prefers to lay closer to three-coordinated B atoms, forming B-NBO bonds, with respect to Si and especially Al. This can explain the formation of AlO5 and AlO6 units in the investigated Na-free glass, together with a Si clusterization

    Inferring age-specific differences in susceptibility to and infectiousness upon SARS-CoV-2 infection based on Belgian social contact data

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    Several important aspects related to SARS-CoV-2 transmission are not well known due to a lack of appropriate data. However, mathematical and computational tools can be used to extract part of this information from the available data, like some hidden age-related characteristics. In this paper, we present a method to investigate age-specific differences in transmission parameters related to susceptibility to and infectiousness upon contracting SARS-CoV-2 infection. More specifically, we use panel-based social contact data from diary-based surveys conducted in Belgium combined with the next generation principle to infer the relative incidence and we compare this to real-life incidence data. Comparing these two allows for the estimation of age-specific transmission parameters. Our analysis implies the susceptibility in children to be around half of the susceptibility in adults, and even lower for very young children (preschooler). However, the probability of adults and the elderly to contract the infection is decreasing throughout the vaccination campaign, thereby modifying the picture over time.Comment: Revised version, 17 pages, supplementary material 15 page

    Carbon sequestration and soil nitrogen enrichment in Robinia pseudoacacia L. post-mining restoration plantations

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    Robinia pseudoacacia L. (black locust) has been extensively used for restoring degraded lands, following anthropogenic interventions like coal mining. Here we have addressed the contribution of black locust restoration plantations, established on overburden post-mining material, to carbon storage and to soil nitrogen enrichment at the largest lignite center in Greece. Carbon stocks and fluxes in all pools of the ecosystem, as well as the foliar nitrogen resorption efficiency and soil N stocks were quantified and the effect of plantations’ age was tested. The young age of the plantations (4–24 years) resulted in a relatively low total ecosystem C stock (56.7 t ha−1), which was partitioned among the different pools in the following order: above-ground biomass (50%) > black locust-derived SOC (24%) > coarse roots (14%) > deadwood (6%) > forest floor (5%) > fine roots (less than 1%). Litterfall started early in the growing season and together with fine roots that had a turnover rate of 0.62 yr−1, fueled soil organic carbon. SOC accrual, referring to the accumulation of SOC derived by black locust, declined with age. However, further SOC accumulation is expected, based on the potential SOC storage capacity of soil at the area. C stocks in above- and below-ground biomass increased linearly with age. The same response was observed for soil N stock and NRE, indicating that despite the N2-fixing capacity of black locust, there was still a poor pedospheric N supply and a need for efficient N cycling. Overall, the studied restoration plantations have a considerable contribution to C and N accumulation at the degraded post-mining sites. These positive effects are expected to further increase at least until the plantations reach maturity

    Cytokine Combination Therapy with Erythropoietin and Granulocyte Colony Stimulating Factor in a Porcine Model of Acute Myocardial Infarction

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    PurposeErythropoietin (EPO) and granulocyte colony stimulating factor (GCSF) have generated interest as novel therapies after myocardial infarction (MI), but the effect of combination therapy has not been studied in the large animal model. We investigated the impact of prolonged combination therapy with EPO and GCSF on cardiac function, infarct size, and vascular density after MI in a porcine model.MethodsMI was induced in pigs by a 90 min balloon occlusion of the left anterior descending coronary artery. 16 animals were treated with EPO+GCSF, or saline (control group). Cardiac function was assessed by echocardiography and pressure-volume measurements at baseline, 1 and 6 weeks post-MI. Histopathology was performed 6 weeks post-MI.ResultsAt week 6, EPO+GCSF therapy stabilized left ventricular ejection fraction, (41 ± 1% vs. 33 ± 1%, p < 0.01) and improved diastolic function compared to the control group. Histopathology revealed increased areas of viable myocardium and vascular density in the EPO+GCSF therapy, compared to the control. Despite these encouraging results, in a historical analysis comparing combination therapy with monotherapy with EPO or GCSF, there were no significant additive benefits in the LVEF and volumes overtime using the combination therapy.ConclusionOur findings indicate that EPO+GCSF combination therapy promotes stabilization of cardiac function after acute MI. However, combination therapy does not seem to be superior to monotherapy with either EPO or GCSF

    Coirón Blanco: Avances en su domesticación y mejoramiento genético

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    Los pastizales naturales son el principal recurso forrajero en Patagonia. La ganadería extensiva, el avance de la desertificación y los cambios en el clima contribuyen a un aumento de la degradación de estos pastizales. Domesticar especies forrajeras nativas para llevarlas al cultivo permitirá aumentar la productividad y restaurar pastizales degradados.Estación Experimental Agropecuaria BarilocheFil: Marchelli, Paula. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Area Forestal. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; ArgentinaFil: Lopez, Aldana. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Area Recursos Naturales. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; ArgentinaFil: Azpilicueta, Maria Marta. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Area Forestal. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; ArgentinaFil: Nagahama, Nicolas. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; ArgentinaFil: Ugarte, Cristina Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; ArgentinaFil: Guidalevich, Verónica. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Area Recursos Naturales. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; ArgentinaFil: Angeli, Juan Pablo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; ArgentinaFil: Aparicio, Alejandro Gabriel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Area Forestal. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; ArgentinaFil: Easdale, Marcos Horacio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Area Desarrollo Rural. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; Argentin

    Coirón blanco: avances en su domesticación y mejoramiento genético

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    Los pastizales naturales son el principal recurso forrajero en Patagonia. La ganadería extensiva, el avance de la desertificación y los cambios en el clima contribuyen a un aumento de la degradación de estos pastizales. Domesticar especies forrajeras nativas para llevarlas al cultivo permitirá aumentar la productividad y restaurar pastizales degradados.Fil: Marchelli, Paula. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Instituto de Investigaciones Forestales y Agropecuarias Bariloche. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; ArgentinaFil: López, Aldana Soledad. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Instituto de Investigaciones Forestales y Agropecuarias Bariloche. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; ArgentinaFil: Azpilicueta, María Marta. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Instituto de Investigaciones Forestales y Agropecuarias Bariloche. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; ArgentinaFil: Nagahama, Nicolas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; ArgentinaFil: Ugarte, Cristina Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; ArgentinaFil: Guidalevich, Veronica. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Instituto de Investigaciones Forestales y Agropecuarias Bariloche. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; ArgentinaFil: Angeli, Juan Pablo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Sur. Estación Experimental Agropecuaria Esquel; ArgentinaFil: Aparicio, Alejandro. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Instituto de Investigaciones Forestales y Agropecuarias Bariloche. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; ArgentinaFil: Easdale, Marcos Horacio. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche. Instituto de Investigaciones Forestales y Agropecuarias Bariloche. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; Argentin

    Dietary flavanol intervention lowers the levels of endothelial microparticles in coronary artery disease patients

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    Current evidence suggests that regenerative v. degenerative endothelial responses can be integrated in a clinical endothelial phenotype, reflecting the net result between damage from risk factors and endogenous repair capacity. We have previously shown that a cocoa flavanol (CF) intervention can improve endothelial function and increase the regenerative capacity of the endothelium by mobilising circulating angiogenic cells in patients with coronary artery disease (CAD). The aim of the present study was to investigate whether CF can lower the levels of circulating endothelial microparticles (EMP), markers of endothelial integrity, along with improvements in endothelial function. The levels of EMP in the frozen plasma samples of CAD patients were measured along with endothelial function (flow-mediated vasodilation, FMD); n 16, FMD data published previously), and these data were compared with those of young (n 12) and age-matched (n 12) healthy control subjects. The CAD patients exhibited significantly increased levels of EMP along with impaired FMD when compared with the healthy control subjects. The levels of CD144+ and CD31+/41− EMP were inversely correlated with FMD (r − 0·67, P= 0·01 and r − 0·59, P= 0·01, respectively). In these CAD patients, the levels of EMP were measured after they had consumed a drink containing 375 mg of CF (high-CF intervention, HiFI) or 9 mg of CF (macro- and micronutrient-matched low-CF control, LoFl) twice daily over a 30-d period in a randomised, double-blind, cross-over study. After 1 month of HiFI, the levels of CD31+/41− and CD144+ EMP decreased ( − 25 and − 23 %, respectively), but not after LoFl. Our data show that flavanols lower the levels of EMP along with higher endothelial function, lending evidence to the novel concept that flavanols may improve endothelial integrity
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