1,745 research outputs found

    Atlantic mountain grassland-heathlands: structure and feeding value

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    Atlantic mountain pastures are composed by mosaics of semi-natural grasslands and heathlands. A knowledge of their structure and feeding value is useful to understand their livestock use and improve management of these communities. This study was carried out in the Gorbeia Natural Park in northern Spain. Pasture composition, sward height and nutritive value were measured over four grazing seasons (spring, summer, late summer and autumn) in three plant communities: grassland (GR), open heathland (OH) and dense heathland (DH). The grassland community had lower sward height and better nutritive value. In less favoured grazing periods, when sward height in GR becomes limiting livestock move to OH with higher pasture height and lower sward cover and nutritive value. Even both heathlands have similar height and quality, the selection of OH, and avoiding of the dense one, could be due to its higher sward cover, which could make it easier to look for feed. Moreover, considering the woody component the estimated nutritive value of DH does not cover the minimum required for livestock production

    Global versus local environmental impacts of grazing and confined beef production systems

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    Carbon footprint is a key indicator of the contribution of food production to climate change and its importance is increasing worldwide. Although it has been used as a sustainability index for assessing production systems, it does not take into account many other biophysical environmental dimensions more relevant at the local scale, such as soil erosion, nutrient imbalance, and pesticide contamination. We estimated carbon footprint, fossil fuel energy use, soil erosion, nutrient imbalance, and risk of pesticide contamination for five real beef background-finishing systems with increasing levels of intensification in Uruguay, which were combinations of grazing rangelands (RL), seeded pastures (SP), and confined in feedlot (FL). Carbon footprint decreased from 16.7 (RL–RL) to 6.9 kg (SP–FL) CO2 eq kg body weight-1 (BW; 'eq': equivalent). Energy use was zero for RL–RL and increased up to 17.3 MJ kg BW-1 for SP–FL. Soil erosion values varied from 7.7 (RL–RL) to 14.8 kg of soil kg BW-1 (SP–FL). Nitrogen and phosphorus nutrient balances showed surpluses for systems with seeded pastures and feedlots while RL–RL was deficient. Pesticide contamination risk was zero for RL–RL, and increased up to 21.2 for SP–FL. For the range of systems studied with increasing use of inputs, trade-offs were observed between global and local environmental problems. These results demonstrate that several indicators are needed to evaluate the sustainability of livestock production systems

    The Dexi-SH* model for a multivariate assessment of agro-ecological sustainability of dairy grazing systems

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    Dexi-SH* is an ex ante multivariate model for assessing the sustainability of dairy cows grazing systems. This model is composed of three sub-models that evaluate the impact of the systems on: (i) biotic resources; (ii) abiotic resources, and (iii) pollution risks. The structuring of the hierarchical tree was inspired by that of the Masc model. The choice of criteria and their aggregation modalities were discussed within a multi-disciplinary group of scientists. For each cluster, a utility function was established in order to determine weighting and priority functions between criteria. The model can take local and regional conditions and standards into account by adjusting criterion categories to the agroecological context, and the specific views of the decision makers by changing the weighting of criteria

    Different ratio of soluble and insoluble fiber in the pig diet

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    Se evaluó la inclusión progresiva de dos forrajes con diferente contenido en fibra soluble (FS), en dietas de cerdos desde la recría a la terminación. Los tratamientos fueron: dieta base testigo (T0) formulada en base a maíz y harina de soja; dieta base con alfalfa (T1) (Medicago sativa var. Chaná) o con achicoria (T2) (Cichorium intibus var. Lacerta) para las fases (F) de recría I (F1, 40-60 kg de PV), recría II (F2, 60-80 kg de PV) y terminación (F3, 80 a 100 kg de PV). Se utilizaron 27 animales con un peso inicial de 42 kg (± 2.3), en un diseño de parcelas al azar en tres tratamientos con nueve repeticiones. El peso final y la ganancia diaria no difirieron entre tratamientos. El consumo de Fibra Dietaria fue mayor en los tratamientos con forraje (P<0.05), mientras el consumo de FS fue mayor en la dieta con achicoria que en la dieta con alfalfa (P<0.05). Este mayor consumo de Fibra Dietaria estuvo asociado a un mayor peso de los componentes del tracto gastrointestinal de los cerdos, en particular el colon en T2 (P<0.05). Como consecuencia, T2 presentó el menor rendimiento de carcasa (77.4%, P<0.05), respecto a T0 y T1, los que fueron similares entre si (80.0 y 78.9% respectivamente, P=0.303). La inclusión progresiva de forraje posibilitó una adaptación física del tracto, mediante el aumento del estómago y colón, pero dicha adaptación afectó el rendimiento de carcasa.The progressive inclusion of two forages with different soluble fibre (FS) content, in diets from growing and finishing pig was evaluated. The treatments were: control diet (T0) formulated based on corn and soybean meal; base diet with alfalfa (T1) (Medicago sativa var. Chaná) or with chicory (T2) (Cichorium intibus var. Lacerta) for stages (F) of growing I (F1, 40-60 kg of PV), growing II (F2, 60-80 kg of PV) and finishing (F3, 80 to 100 kg of PV). 27 animals with an initial weight of 42 kg (± 2.3) were used in a random plot design in three treatments, with nine repetitions. The final weight and daily gain did not differ among treatments. Dietary Fiber consumption was higher in forage treatments (P<0.05), while FS consumption was higher in the chicory diet than the alfalfa diet (P <0.05). This higher consumption of Dietary Fiber was associated with a higher weight of the components of the pigs’ gastrointestinal tract, particularly the colon in T2 (P<0.05). As a consequence, T2 presented the lowest carcass yield (77.4%, P<0.05), compared to T0 and T1, which were similar to each other (80.0 and 78.9% respectively, P=0.303).The progressive inclusion of forage allowed a physical adaptation of the tract, by increasing the stomach and colon but such adaptation affected the carcass yield

    Subversion of early innate antiviral responses during antibody-dependent enhancement of Dengue virus infection induces severe disease in immunocompetent mice

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    Dengue is a mosquito-borne disease caused by one of four serotypes of Dengue virus (DENV-1–4). Epidemiologic and observational studies demonstrate that the majority of severe dengue cases, dengue hemorrhagic fever and dengue shock syndrome (DHF/DSS), occurs predominantly in either individuals with cross-reactive immunity following a secondary heterologous infection or in infants with primary DENV infections born from dengue-immune mothers, suggesting that B-cell-mediated and antibody responses impact on disease evolution. We demonstrate here that B cells play a pivotal role in host responses against primary DENV infection in mice. After infection, μMT[superscript −/−] mice showed increased viral loads followed by severe disease manifestation characterized by intense thrombocytopenia, hemoconcentration, cytokine production and massive liver damage that culminated in death. In addition, we show that poly and monoclonal anti-DENV-specific antibodies can sufficiently increase viral replication through a suppression of early innate antiviral responses and enhance disease manifestation, so that a mostly non-lethal illness becomes a fatal disease resembling human DHF/DSS. Finally, treatment with intravenous immunoglobulin containing anti-DENV antibodies confirmed the potential enhancing capacity of subneutralizing antibodies to mediate virus infection and replication and induce severe disease manifestation of DENV-infected mice. Thus, our results show that humoral responses unleashed during DENV infections can exert protective or pathological outcomes and provide insight into the pathogenesis of this important human pathogen

    Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

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    This paper presents measurements of the W+μ+νW^+ \rightarrow \mu^+\nu and WμνW^- \rightarrow \mu^-\nu cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

    Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in √s=13 TeV pp collisions with the ATLAS detector

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    A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of √s=13  TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139  fb−1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015–2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV

    ECLIM-SEHOP, a new platform to set up and develop international academic clinical trials for childhood cancer and blood disorders in Spain

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    Introduction: Cancer and blood disorders in children are rare. The progressive improvement in survival over the last decades largely relies on the development of international academic clinical trials that gather the sufcient number of patients globally to elaborate solid conclusions and drive changes in clinical practice. The participation of Spain into large international academic trials has traditionally lagged behind of other European countries, mainly due to the burden of administrative tasks to open new studies, lack of fnancial support and limited research infrastructure in our hospitals. Methods: The objective of ECLIM-SEHOP platform (Ensayos Clínicos Internacionales Multicéntricos-SEHOP) is to overcome these difculties and position Spain among the European countries leading the advances in cancer and blood disorders, facilitate the access of our patients to novel diagnostic and therapeutic approaches and, most importantly, continue to improve survival and reducing long-term sequelae. ECLIM-SEHOP provides to the Spanish clinical investigators with the necessary infrastructural support to open and implement academic clinical trials and registries. Results: In less than 3 years from its inception, the platform has provided support to 20 clinical trials and 8 observational studies, including 8 trials and 4 observational studies where the platform performs all trial-related tasks (integral support: trial setup, monitoring, etc.) with more than 150 patients recruited since 2017 to these studies. In this manuscript, we provide baseline metrics for academic clinical trial performance that permit future comparisons. Conclusions: ECLIM-SEHOP facilitates Spanish children and adolescents diagnosed with cancer and blood disorders to access state-of-the-art diagnostic and therapeutic strategies

    Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

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    Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente
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