3 research outputs found

    Improving Latin American soil information database for digital soil mapping enhances its usability and scalability

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    Spatial soil databases can help model complex phenomena in which soils are decisive, for example, evaluating agricultural potential or estimating carbon storage capacity. The Soil Information System for Latin America and the Caribbean, SISLAC, is a regional initiative promoted by the FAO's South American Soil Partnership to contribute to the sustainable management of soil. SISLAC includes data coming from 49,084 soil profiles distributed unevenly across the continent, making it the region's largest soil database. However, some problems hinder its usages, such as the quality of the data and its high dimensionality. The objective of this research is twofold. First, to evaluate the quality of SISLAC and its data values and generate a new, improved version that meets the minimum quality requirements to be used by different interests or practical applications. Second, to demonstrate the potential of improved soil profile databases to generate more accurate information on soil properties, by conducting a case study to estimate the spatial variability of the percentage of soil organic carbon using 192 profiles in a 1473 km2 region located in the department of Valle del Cauca, Colombia. The findings show that 15 percent of the existing soil profiles had an inaccurate description of the diagnostic horizons. Further correction of an 4.5 additional percent of existing inconsistencies improved overall data quality. The improved database consists of 41,691 profiles and is available for public use at ttps://doi.org/10.5281/zenodo.6540710 (Díaz-Guadarrama, S. & Guevara, M., 2022). The updated profiles were segmented using algorithms for quantitative pedology to estimate the spatial variability. We generated segments one centimeter thick along with each soil profile data, then the values of these segments were adjusted using a spline-type function to enhance vertical continuity and reliability. Vertical variability was estimated up to 150 cm in-depth, while ordinary kriging predicts horizontal variability at three depth intervals, 0 to 5, 5 to 15, and 15 to 30 cm, at 250 m-spatial resolution, following the standards of the GlobalSoilMap project. Finally, the leave-one-out cross validation provides information for evaluating the kriging model performance, obtaining values for the RMSE index between 1.77% and 1.79% and the R2 index greater than 0.5. The results show the usability of SISLAC database to generate spatial information on soil properties and suggest further efforts to collect a more significant amount of data to guide sustainable soil management.Fil: Diaz Guadamarra, Sergio. Universidad Nacional de Colombia. Facultad de Ciencias Agrarias. Departamento de Agronomía; ColombiaFil: Lizarazo, Iván. Universidad Nacional de Colombia. Facultad de Ciencias Agrarias. Departamento de Agronomía; ColombiaFil: Guevara, Mario. Universidad Nacional Autónoma de México. Campus Juriquilla. Centro de Geociencias; MéxicoFil: Guevara, Mario. Universidad Nacional Autónoma de México.Campus Juriquilla. Centro de Geociencias; México. United States Department of Agriculture. Soil Salinity National Laboratory, Estados UnidosFil: Angelini, Marcos Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Suelos; Argentina. Wageningen University. Soil Geography and Landscape Group; Países Bajos. International Soil Reference and Information Centre. World Soil Information; Países BajosFil: Araujo Carrillo, Gustavo A. Corporación Colombiana de Investigación Agropecuaria AGROSAVIA; ColombiaFil: Argeñal, Jainer. Universidad Nacional Autónoma de Honduras. Facultad de Ciencias; Honduras.Fil: Armas, Daphne. Universidad de Almería. Departamento de Agronomía, Edif. CITEIIB, España.Fil: Balsa, Rafael A. Ministerio de Desarrollo Agrario y Riego. Dirección General de Asuntos Ambientales Agrarios, Perú.Fil: Bolivar, Adriana. Instituto Geográfico Agustín Codazzi. Subdirección Agrología; ColombiaFil: Bustamante, Nelson. Servicio Agrícola y Ganadero; Chile.Fil: Dart, Ricardo O. Embrapa Solos; BrasilFil: Dell Acqua, Martín. Ministerio de Ganadería, Agricultura y Pesca. Dirección General de Recursos Naturales; UruguayFil: Lencina, Arnulfo. Universidad Nacional de Asunción. Facultad de Ciencias Agrarias; ParaguayFil: Figueredo, Hernán. Sociedad Boliviana de la Ciencia del Suelo; Bolivia.Fil: Fontes, Fernando. Ministerio de Ganadería, Agricultura y Pesca. Dirección General de Recursos Naturales; UruguayFil: Gutierrez Diaz, Joan S. Aarhus University. Faculty of Science and Technology,.Department of Agroecology; DinamarcaFil: Jiménez, Wilmer. Ministerio de Agricultura y Ganadería; Ecuador.Fil: Rodriguez, Dario Martin. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Suelos; ArgentinaFil: Schulz, Guillermo. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Suelos; ArgentinaFil: Tenti Vuegen, Leonardo Mauricio. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Suelos; Argentin

    Measurements of the Total and Differential Higgs Boson Production Cross Sections Combining the H??????? and H???ZZ*???4??? Decay Channels at s\sqrt{s}=8??????TeV with the ATLAS Detector

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    Measurements of the total and differential cross sections of Higgs boson production are performed using 20.3~fb1^{-1} of pppp collisions produced by the Large Hadron Collider at a center-of-mass energy of s=8\sqrt{s} = 8 TeV and recorded by the ATLAS detector. Cross sections are obtained from measured HγγH \rightarrow \gamma \gamma and HZZ4H \rightarrow ZZ ^{*}\rightarrow 4\ell event yields, which are combined accounting for detector efficiencies, fiducial acceptances and branching fractions. Differential cross sections are reported as a function of Higgs boson transverse momentum, Higgs boson rapidity, number of jets in the event, and transverse momentum of the leading jet. The total production cross section is determined to be σppH=33.0±5.3(stat)±1.6(sys)pb\sigma_{pp \to H} = 33.0 \pm 5.3 \, ({\rm stat}) \pm 1.6 \, ({\rm sys}) \mathrm{pb}. The measurements are compared to state-of-the-art predictions.Measurements of the total and differential cross sections of Higgs boson production are performed using 20.3  fb-1 of pp collisions produced by the Large Hadron Collider at a center-of-mass energy of s=8  TeV and recorded by the ATLAS detector. Cross sections are obtained from measured H→γγ and H→ZZ*→4ℓ event yields, which are combined accounting for detector efficiencies, fiducial acceptances, and branching fractions. Differential cross sections are reported as a function of Higgs boson transverse momentum, Higgs boson rapidity, number of jets in the event, and transverse momentum of the leading jet. The total production cross section is determined to be σpp→H=33.0±5.3 (stat)±1.6 (syst)  pb. The measurements are compared to state-of-the-art predictions.Measurements of the total and differential cross sections of Higgs boson production are performed using 20.3 fb1^{-1} of pppp collisions produced by the Large Hadron Collider at a center-of-mass energy of s=8\sqrt{s} = 8 TeV and recorded by the ATLAS detector. Cross sections are obtained from measured HγγH \rightarrow \gamma \gamma and HZZ4H \rightarrow ZZ ^{*}\rightarrow 4\ell event yields, which are combined accounting for detector efficiencies, fiducial acceptances and branching fractions. Differential cross sections are reported as a function of Higgs boson transverse momentum, Higgs boson rapidity, number of jets in the event, and transverse momentum of the leading jet. The total production cross section is determined to be σppH=33.0±5.3(stat)±1.6(sys)pb\sigma_{pp \to H} = 33.0 \pm 5.3 \, ({\rm stat}) \pm 1.6 \, ({\rm sys}) \mathrm{pb}. The measurements are compared to state-of-the-art predictions

    Ticagrelor in patients with diabetes and stable coronary artery disease with a history of previous percutaneous coronary intervention (THEMIS-PCI) : a phase 3, placebo-controlled, randomised trial

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    Background: Patients with stable coronary artery disease and diabetes with previous percutaneous coronary intervention (PCI), particularly those with previous stenting, are at high risk of ischaemic events. These patients are generally treated with aspirin. In this trial, we aimed to investigate if these patients would benefit from treatment with aspirin plus ticagrelor. Methods: The Effect of Ticagrelor on Health Outcomes in diabEtes Mellitus patients Intervention Study (THEMIS) was a phase 3 randomised, double-blinded, placebo-controlled trial, done in 1315 sites in 42 countries. Patients were eligible if 50 years or older, with type 2 diabetes, receiving anti-hyperglycaemic drugs for at least 6 months, with stable coronary artery disease, and one of three other mutually non-exclusive criteria: a history of previous PCI or of coronary artery bypass grafting, or documentation of angiographic stenosis of 50% or more in at least one coronary artery. Eligible patients were randomly assigned (1:1) to either ticagrelor or placebo, by use of an interactive voice-response or web-response system. The THEMIS-PCI trial comprised a prespecified subgroup of patients with previous PCI. The primary efficacy outcome was a composite of cardiovascular death, myocardial infarction, or stroke (measured in the intention-to-treat population). Findings: Between Feb 17, 2014, and May 24, 2016, 11 154 patients (58% of the overall THEMIS trial) with a history of previous PCI were enrolled in the THEMIS-PCI trial. Median follow-up was 3·3 years (IQR 2·8–3·8). In the previous PCI group, fewer patients receiving ticagrelor had a primary efficacy outcome event than in the placebo group (404 [7·3%] of 5558 vs 480 [8·6%] of 5596; HR 0·85 [95% CI 0·74–0·97], p=0·013). The same effect was not observed in patients without PCI (p=0·76, p interaction=0·16). The proportion of patients with cardiovascular death was similar in both treatment groups (174 [3·1%] with ticagrelor vs 183 (3·3%) with placebo; HR 0·96 [95% CI 0·78–1·18], p=0·68), as well as all-cause death (282 [5·1%] vs 323 [5·8%]; 0·88 [0·75–1·03], p=0·11). TIMI major bleeding occurred in 111 (2·0%) of 5536 patients receiving ticagrelor and 62 (1·1%) of 5564 patients receiving placebo (HR 2·03 [95% CI 1·48–2·76], p<0·0001), and fatal bleeding in 6 (0·1%) of 5536 patients with ticagrelor and 6 (0·1%) of 5564 with placebo (1·13 [0·36–3·50], p=0·83). Intracranial haemorrhage occurred in 33 (0·6%) and 31 (0·6%) patients (1·21 [0·74–1·97], p=0·45). Ticagrelor improved net clinical benefit: 519/5558 (9·3%) versus 617/5596 (11·0%), HR=0·85, 95% CI 0·75–0·95, p=0·005, in contrast to patients without PCI where it did not, p interaction=0·012. Benefit was present irrespective of time from most recent PCI. Interpretation: In patients with diabetes, stable coronary artery disease, and previous PCI, ticagrelor added to aspirin reduced cardiovascular death, myocardial infarction, and stroke, although with increased major bleeding. In that large, easily identified population, ticagrelor provided a favourable net clinical benefit (more than in patients without history of PCI). This effect shows that long-term therapy with ticagrelor in addition to aspirin should be considered in patients with diabetes and a history of PCI who have tolerated antiplatelet therapy, have high ischaemic risk, and low bleeding risk
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