1,864 research outputs found

    Present day background of nitrate as a methodology in the surface water - groundwater interaction applied in southeastern Buenos Aires province, Argentina

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    La contaminación con nitrato en agua superficial y subterránea es un problema mundial vinculado especialmente con la intensa actividad agrícola. Las concentraciones elevadas afectan la calidad de las aguas y resulta ser un indicador importante de la influencia del hombre. En un acuífero libre de una cuenca de llanura en el sudeste bonaerense en Argentina se midieron 4-235 mg/L en octubre 2013 y 5,7-250 mg/L en julio 2014. Respecto a los tenores en el agua superficial se midieron concentraciones de 7–79,6 mg/L durante octubre 2013-julio 2014 y 1–120 mg/L de julio 2014 a abril 2015. Se calcularon los valores de Fondo Actual del acuífero mediante un análisis estadístico y se los comparó para monitorear sus variaciones. En cuanto al agua superficial, se calcularon sus variaciones de Fondo Actual en los dos periodos para cotejarlos con el acuífero. A partir de los resultados se propone una nueva metodología para analizar la vinculación agua superficial-subterránea.Nitrate contamination of surface and groundwater is a global problem which is related to the intense agricultural activity. The high concentrations affect the waters quality and it turns out to be an important indicator of the human influence. In the phreatic aquifer in a plain basin in southeastern Buenos Aires province of Argentina, nitrate has values between 4 and 235 mg/L measured in October 2013 and 5.7-250 mg/L in July 2014. Respect to the values in surface water, were measured concentrations of 7-79, 6 mg/L during October 2013-July 2014 and 1-120 mg/L from July 2014 to April 2015. The present day background values found in the aquifer were calculated through a statistical analysis and compared to monitor their variations. Also, were calculated in the two periods the present day background superficial water to compare them with the aquifer. Based on the results, a new methodology is proposed to analyze the surface-groundwater linkage.Fil: Calvi, Carolina Maria Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geocronología y Geología Isotópica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geocronología y Geología Isotópica; ArgentinaFil: Dapeña, Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geocronología y Geología Isotópica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geocronología y Geología Isotópica; ArgentinaFil: Martinez, Daniel Emilio. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Geología de Costas y del Cuaternario. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Geología de Costas y del Cuaternario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Les droits disciplinaires des fonctions publiques : « unification », « harmonisation » ou « distanciation ». A propos de la loi du 26 avril 2016 relative à la déontologie et aux droits et obligations des fonctionnaires

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    The production of tt‾ , W+bb‾ and W+cc‾ is studied in the forward region of proton–proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98±0.02 fb−1 . The W bosons are reconstructed in the decays W→ℓν , where ℓ denotes muon or electron, while the b and c quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions.The production of ttt\overline{t}, W+bbW+b\overline{b} and W+ccW+c\overline{c} is studied in the forward region of proton-proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98 ±\pm 0.02 \mbox{fb}^{-1}. The WW bosons are reconstructed in the decays WνW\rightarrow\ell\nu, where \ell denotes muon or electron, while the bb and cc quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions

    Measurement of the forward Z boson production cross-section in pp collisions at s=13\sqrt{s} = 13 TeV

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    A measurement of the production cross-section of Z bosons in pp collisions at s=13\sqrt{s} = 13 TeV is presented using dimuon and dielectron final states in LHCb data. The cross-section is measured for leptons with pseudorapidities in the range 2.0η4.52.0 \eta 4.5, transverse momenta pT20p_\text{T} 20 GeV and dilepton invariant mass in the range 60m()12060 m(\ell\ell) 120 GeV. The integrated cross-section from averaging the two final states is \begin{equation*}\sigma_{\text{Z}}^{\ell\ell} = 194.3 \pm 0.9 \pm 3.3 \pm 7.6\text{ pb,}\end{equation*} where the first uncertainty is statistical, the second is due to systematic effects, and the third is due to the luminosity determination. In addition, differential cross-sections are measured as functions of the Z boson rapidity, transverse momentum and the angular variable ϕη\phi^*_\eta

    Análisis de las variaciones hidrogeoquímicas de manantiales de la cordillera sanjuanina

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    Las descargas de agua subterránea sostenidas en el tiempo, como es el caso de los manantiales que alimentan a los mallines en el entorno árido cordillerano de la provincia de San Juan, son fundamentales para el abastecimiento de agua local, así como para conservar y garantizar la biodiversidad y el funcionamiento hidrológico del ecosistema de alta montaña. En este tipo de ambiente, es crucial considerar tanto la cantidad como la calidad del recurso para sus diversos usos. El quimismo resultante dependerá de la composición mineralógica de las formaciones geológicas con las que el agua interacciona y de su tiempo de contacto . Por tanto, el objetivo del trabajo es analizar las variaciones hidrogeoquímicas que surgen de la interacción agua-roca y afectan la composición de manantiales localizados en las Cordilleras Principal, Frontal, y un sector transicional entre ambas. Para lograrlo, se realizaron relevamientos de campo de las formaciones geológicas que atraviesa el agua y se tomaron 18 muestras de manantiales para análisis de iones mayoritarios en laboratorio. De la totalidad de las muestras, cuatro corresponden a Pampa Manantial (PM, Cordillera Frontal), cuatro a Vega Gallardo (VG, sector transicional) y diez muestras a Valle Hermoso (VH, Cordillera Principal).Fil: Calvi, Carolina Maria Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geocronología y Geología Isotópica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geocronología y Geología Isotópica; ArgentinaFil: Carol, Eleonora Silvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Fennell, Lucas Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Di Lello, Claudia Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Naipauer, Maximiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geocronología y Geología Isotópica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geocronología y Geología Isotópica; ArgentinaXI Jornadas de las Ciencias de la Tierra Dr. Eduardo MusacchioChubutArgentinaUniversidad Nacional de la Patagonia San Juan Bosco. Facultad de Ciencias Naturales y Ciencias de la Salud. Departamento de Geologí

    Understanding the relationship between cognitive performance and function in daily life after traumatic brain injury

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    Objective: Cognitive impairment is a key cause of disability after traumatic brain injury (TBI) but relationships with overall functioning in daily life are often modest. The aim is to examine cognition at different levels of function and identify domains associated with disability. Methods: 1554 patients with mild-to-severe TBI were assessed at 6 months post injury on the Glasgow Outcome Scale—Extended (GOSE), the Short Form-12v2 and a battery of cognitive tests. Outcomes across GOSE categories were compared using analysis of covariance adjusting for age, sex and education. Results: Overall effect sizes were small to medium, and greatest for tests involving processing speed (ηp2 0.057–0.067) and learning and memory (ηp2 0.048–0.052). Deficits in cognitive performance were particularly evident in patients who were dependent (GOSE 3 or 4) or who were unable to participate in one or more major life activities (GOSE 5). At higher levels of function (GOSE 6–8), cognitive performance was surprisingly similar across categories. There were decreases in performance even in patients reporting complete recovery without significant symptoms. Medium to large effect sizes were present for summary measures of cognition (ηp2 0.111), mental health (ηp2 0.131) and physical health (ηp2 0.252). Conclusions: This large-scale study provides novel insights into cognitive performance at different levels of disability and highlights the importance of processing speed in function in daily life. At upper levels of outcome, any influence of cognition on overall function is markedly attenuated and differences in mental health are salient.publishedVersion© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ

    Comparative effectiveness of intracranial hypertension management guided by ventricular versus intraparenchymal pressure monitoring:a CENTER-TBI study

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    Objective: To compare outcomes between patients with primary external ventricular device (EVD)–driven treatment of intracranial hypertension and those with primary intraparenchymal monitor (IP)–driven treatment. Methods: The CENTER-TBI study is a prospective, multicenter, longitudinal observational cohort study that enrolled patients of all TBI severities from 62 participating centers (mainly level I trauma centers) across Europe between 2015 and 2017. Functional outcome was assessed at 6 months and a year. We used multivariable adjusted instrumental variable (IV) analysis with “center” as instrument and logistic regression with covariate adjustment to determine the effect estimate of EVD on 6-month functional outcome. Results: A total of 878 patients of all TBI severities with an indication for intracranial pressure (ICP) monitoring were included in the present study, of whom 739 (84%) patients had an IP monitor and 139 (16%) an EVD. Patients included were predominantly male (74% in the IP monitor and 76% in the EVD group), with a median age of 46 years in the IP group and 48 in the EVD group. Six-month GOS-E was similar between IP and EVD patients (adjusted odds ratio (aOR) and 95% confidence interval [CI] OR 0.74 and 95% CI [0.36–1.52], adjusted IV analysis). The length of intensive care unit stay was greater in the EVD group than in the IP group (adjusted rate ratio [95% CI] 1.70 [1.34–2.12], IV analysis). One hundred eighty-seven of the 739 patients in the IP group (25%) required an EVD due to refractory ICPs. Conclusion: We found no major differences in outcomes of patients with TBI when comparing EVD-guided and IP monitor–guided ICP management. In our cohort, a quarter of patients that initially received an IP monitor required an EVD later for ICP control. The prevalence of complications was higher in the EVD group. Protocol: The core study is registered with ClinicalTrials.gov, number NCT02210221, and the Resource Identification Portal (RRID: SCR_015582).</p

    Prehospital Management of Traumatic Brain Injury across Europe: A CENTER-TBI Study.

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    BACKGROUND: Prehospital care for traumatic brain injury (TBI) is important to prevent secondary brain injury. We aim to compare prehospital care systems within Europe and investigate the association of system characteristics with the stability of patients at hospital arrival. METHODS: We studied TBI patients who were transported to CENTER-TBI centers, a pan-European, prospective TBI cohort study, by emergency medical services between 2014 and 2017. The association of demographic factors, injury severity, situational factors, and interventions associated with on-scene time was assessed using linear regression. We used mixed effects models to investigate the case mix adjusted variation between countries in prehospital times and interventions. The case mix adjusted impact of on-scene time and interventions on hypoxia (oxygen saturation <90%) and hypotension (systolic blood pressure <100mmHg) at hospital arrival was analyzed with logistic regression. RESULTS: Among 3878 patients, the greatest driver of longer on-scene time was intubation (+8.3 min, 95% CI: 5.6-11.1). Secondary referral was associated with shorter on-scene time (-5.0 min 95% CI: -6.2- -3.8). Between countries, there was a large variation in response (range: 12-25 min), on-scene (range: 16-36 min) and travel time (range: 15-32 min) and in prehospital interventions. These variations were not explained by patient factors such as conscious level or severity of injury (expected OR between countries: 1.8 for intubation, 1.8 for IV fluids, 2.0 for helicopter). On-scene time was not associated with the regional EMS policy (p= 0.58). Hypotension and/or hypoxia were seen in 180 (6%) and 97 (3%) patients in the overall cohort and in 13% and 7% of patients with severe TBI (GCS <8). The largest association with secondary insults at hospital arrival was with major extracranial injury: the OR was 3.6 (95% CI: 2.6-5.0) for hypotension and 4.4 (95% CI: 2.9-6.7) for hypoxia. DISCUSSION: Hypoxia and hypotension continue to occur in patients who suffer a TBI, and remain relatively common in severe TBI. Substantial variation in prehospital care exists for patients after TBI in Europe, which is only partially explained by patient factors

    Association of early blood-based biomarkers and six-month functional outcomes in conventional severity categories of traumatic brain injury: capturing the continuous spectrum of injury

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    Background - Traumatic brain injury is conventionally categorised as mild, moderate, or severe on the Glasgow Coma Scale (GCS). Recently developed biomarkers can provide more objective and nuanced measures of the extent of brain injury. Methods - Exposure–response relationships were investigated in 2479 patients aged ≥16 enrolled in the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) prospective observational cohort study. Neurofilament protein-light (NFL), ubiquitin carboxy-terminal hydrolase L1 (UCH-L1), and glial fibrillary acidic protein (GFAP) were assayed from serum sampled in the first 24 h; concentrations were divided into quintiles within GCS severity groups. Relationships with the Glasgow Outcome Scale-Extended were examined using modified Poisson regression including age, sex, major extracranial injury, time to sample, and log biomarker concentration as covariates. Findings - Within severity groups there were associations between biomarkers and outcomes after adjustment for covariates: GCS 13–15 and negative CT imaging (relative risks [RRs] from 1.28 to 3.72), GCS 13–15 and positive CT (1.21–2.81), GCS 9–12 (1.16–2.02), GCS 3–8 (1.09–1.94). RRs were associated with clinically important differences in expectations of prognosis. In patients with GCS 3 (RRs 1.51–1.80) percentages of unfavourable outcome were 37–51% in the lowest quintiles of biomarker levels and reached 90–94% in the highest quintiles. Similarly, for GCS 15 (RRs 1.83–3.79), the percentages were 2–4% and 19–28% in the lowest and highest biomarker quintiles, respectively. Interpretation - Conventional TBI severity classification is inadequate and underestimates heterogeneity of brain injury and associated outcomes. The adoption of circulating biomarkers can add to clinical assessment of injury severity

    Factorial validity and comparability of the six translations of the Rivermead Post-Concussion Symptoms Questionnaire translations: results from the CENTER-TBI study

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    Background Comparison of patient-reported outcomes in multilingual studies requires evidence of the equivalence of translated versions of the questionnaires. The present study examines the factorial validity and comparability of six language versions of the Rivermead Post-Concussion Symptoms Questionnaire (RPQ) administered to individuals following traumatic brain injury (TBI) in the Collaborative European NeuroTrauma Effectiveness Research (CENTER-TBI) study. Methods Six competing RPQ models were estimated using data from Dutch (n = 597), English (n = 223), Finnish (n = 213), Italian (n = 268), Norwegian (n = 263), and Spanish (n = 254) language samples recruited six months after injury. To determine whether the same latent construct was measured by the best-fitting model across languages and TBI severity groups (mild/moderate vs. severe), measurement invariance (MI) was tested using a confirmatory factor analysis framework. Results The results did not indicate a violation of the MI assumption. The six RPQ translations were largely comparable across languages and were able to capture the same construct across TBI severity groups. The three-factor solution comprising emotional, cognitive, and somatic factors provided the best fit with the following indices for the total sample: χ2 (101) = 647.04, = 6.41, p < 0.001, CFI = 0.995, TLI = 0.994, RMSEA = 0.055, CI90%[0.051, 0.059], SRMR = 0.051. Conclusion The RPQ can be used in international research and clinical settings, allowing direct comparisons of scores across languages analyzed within the full spectrum of TBI severity. To strengthen the aggregated applicability across languages, further analyses of the utility of the response scale and comparisons between different translations of the RPQ at the item level are recommended.publishedVersio
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