1,595 research outputs found

    Combining raw and compositional data to determine the spatial patterns of potentially toxic elements in soils

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    When considering complex scenarios involving several attributes, such as in environmental characterization, a clearer picture of reality can be achieved through the dimensional reduction of data. In this context, maps facilitate the visualization of spatial patterns of contaminant distribution and the identification of enriched areas. A set, of 15 Potentially Toxic Elements (PTEs) – (As, Ba, Cd, Co, Cr, Cu, Hg,Mo, Ni, Pb, Sb, Se, Tl, V, and Zn), was measured in soil, collected in Langreo's municipality (80 km2), Spain. Relative enrichment (RE) is introduced here to refer to the proportion of elements present in a given context. Indeed, a novel approach is provided for research into PTE fate. This method involves studying the variability of PTE proportions throughout the study area, thereby allowing the identification of dissemination trends. Traditional geostatistical approaches commonly use raw data (concentrations) accepting that the elements analyzedmake up the entirety of the soil. However, in geochemical studies the analyzed elements are just a fraction of the total soil composition. Therefore, considering compositional data is pivotal. The spatial characterization of PTEs considering raw and compositional data together allowed a broad discussion about, not only the PTEs concentration's distribution but also to reckon possible trends of relative enrichment (RE). Transformations to open closed data are widely used for this purpose. Spatial patterns have an indubitable interest. In this study, the Centered Log-ratio transformation (clr) was used, followed by its back-transformation, to build a set of compositional data that, combined with raw data, allowed to establish the sources of the PTEs and trends of spatial dissemination.info:eu-repo/semantics/publishedVersio

    Zigomicosis rino-sinuso-orbital post-traumática

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    Se describe un caso de zigomicosis rino-seno.orbital en un paciente sin antecedentes de inmunodeficiencia que presenta exolftalmia izquierda y lesiones infiltrativas edematosas edematosas en párpado inferior, nariza y región malar homolateral de rápida evolución.El hallazgo de abundantes hifas hialinas anchas, no tabicadas y tortuosas en biopsia cutánea de fístula infraorbitaria y en secreción nasal, junto a la obtención de cultivos puros de Rhizopus oryzae, confirmaron el diagnóstico.La extracción del 2º molar superior izquierdo se interpretó como factor local de implantacoón traumática del agente etiológico  el reconocimiento de los síntomas clínicos iniciales fue crucial para el diagnóstico precoz.Esta micosis no constituye un grave  problema de salud. no obstante, en Tucumán, debe tenerse presente su existenci

    Nova metodologia para a construção de Índices Composicionais de Poluição em solos: um estudo de caso em Langreo, Espanha

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    O complexo comportamento geoquímico de Elementos Potencialmente Tóxicos (EPT) em solos pode afetar severamente os ecossistemas e a saúde humana. No entanto, é necessário compreender primeiro o que se entende por um solo “limpo” para depois poder avaliar um solo “poluído “e correspondente grau de severidade associado. Tendo em conta que a composição química de um solo é composicional, os atributos variam juntos, é, neste trabalho, introduzida uma nova metodologia para a construção de Indicadores Composicionais com base no formalismo da Análise de Dados Composicionais (CoDa). Na identificação de um equilíbrio composicional é necessário definir os elementos poluentes e os não poluentes para depois construir um Indicador de Poluição Composicional (IPC). Apresenta-se como estudo de caso a região contaminada de Langreo, noroeste de Espanha, onde num conjunto de 150 amostras de solo georreferenciadas foram analisados, em cada amostra, 37 elementos químicos. Calcularam-se depois, três IPCs, com base no formalismo CoDa e no conhecimento pericial. Num último passo, foram construídos mapas de distribuição espacial e de probabilidade, de exceder um dado limite, para os três novos indicadores de poluição, através de um processo estocástico de simulação sequencial – Simulação Sequencial Gaussiana (SSG). Os padrões espaciais obtidos e correspondente variabilidade associada, permitiu uma melhor compreensão dos processos associados à distribuição e ao enriquecimento relativo em EPTs.info:eu-repo/semantics/publishedVersio

    Assessment of metal and metalloid contamination in soils trough compositional data: the old Mortórios uranium mine area, central Portugal

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    Soils from the old Mortórios uranium mine area were studied to look for contamination, as they are close to two villages, up to 3 km away, and used for agriculture. They are mainly contaminated in U and As and constitute an ecological threat. This study attempts to outline the degree to which soils have been affected by the old mining activities through the computation of significant hot clusters, Traditional geostatistical approaches commonly use raw data (concentrations) accepting that the analyzed elements represent the soil’s entirety. However, in geochemical studies these elements are just a fraction of the total soil composition. Thus, considering compositional data is pivotal. The spatial characterization, considering raw and compositional data together, allowed a broad discussion about not only the concentrations’ spatial distribution, but also a better understanding on the possibility of trends of “relative enrichment” (RE) and, furthermore an insight in U and As fate. The highest proportions (Compositional data) on U (up to 33%), As (up to 35%) and Th (up to 13 %) are reached in the south-southeast segment. However, the highest concentrations (Raw data) occur in north and northwest of the studied area, pointing out to a “relative enrichment” towards the south-southeast zone. The Mondego Sul area is mainly contaminated in U and As, but also in Co, Cu, Pb and Sb. The Mortórios area is less contaminated than the Mondego Sul area.This research was supported by the Fundação para a Ciência e a Tecnologia through projects UID/ GEO/04035/201C and UID/MAR/04292/2013-MARE (PPC). Boente obtained a grant from the ‘‘Formación del Profesorado Universitario’’ program, financed by the ‘‘Ministerio de Educación, Cultura y Deporte de España.’’ M.T.D Albuquerque acknowledges a scholarship 567 SFRH/BSAB/ 127907/2016 from the Foundation for Science and Technology (Portugal)

    Weekly vs. Every-3-Week Paclitaxel and Carboplatin for Ovarian Cancer

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    BACKGROUND A dose-dense weekly schedule of paclitaxel (resulting in a greater frequency of drug delivery) plus carboplatin every 3 weeks or the addition of bevacizumab to paclitaxel and carboplatin administered every 3 weeks has shown efficacy in ovarian cancer. We proposed to determine whether dose-dense weekly paclitaxel and carboplatin would prolong progression-free survival as compared with paclitaxel and carboplatin administered every 3 weeks among patients receiving and those not receiving bevacizumab. METHODS We prospectively stratified patients according to whether they elected to receive bevacizumab and then randomly assigned them to receive either paclitaxel, administered intravenously at a dose of 175 mg per square meter of body-surface area every 3 weeks, plus carboplatin (dose equivalent to an area under the curve [AUC] of 6) for six cycles or paclitaxel, administered weekly at a dose of 80 mg per square meter, plus carboplatin (AUC, 6) for six cycles. The primary end point was progression-free survival. RESULTS A total of 692 patients were enrolled, 84% of whom opted to receive bevacizumab. In the intention-to-treat analysis, weekly paclitaxel was not associated with longer progression-free survival than paclitaxel administered every 3 weeks (14.7 months and 14.0 months, respectively; hazard ratio for disease progression or death, 0.89; 95% confidence interval [CI], 0.74 to 1.06; P=0.18). Among patients who did not receive bevacizumab, weekly paclitaxel was associated with progression-free survival that was 3.9 months longer than that observed with paclitaxel administered every 3 weeks (14.2 vs. 10.3 months; hazard ratio, 0.62; 95% CI, 0.40 to 0.95; P=0.03). However, among patients who received bevacizumab, weekly paclitaxel did not significantly prolong progression-free survival, as compared with paclitaxel administered every 3 weeks (14.9 months and 14.7 months, respectively; hazard ratio, 0.99; 95% CI, 0.83 to 1.20; P=0.60). A test for interaction that assessed homogeneity of the treatment effect showed a significant difference between treatment with bevacizumab and without bevacizumab (P=0.047). Patients who received weekly paclitaxel had a higher rate of grade 3 or 4 anemia than did those who received paclitaxel every 3 weeks (36% vs. 16%), as well as a higher rate of grade 2 to 4 sensory neuropathy (26% vs. 18%); however, they had a lower rate of grade 3 or 4 neutropenia (72% vs. 83%). CONCLUSIONS Overall, weekly paclitaxel, as compared with paclitaxel administered every 3 weeks, did not prolong progression-free survival among patients with ovarian cancer

    Observation of an Excited Bc+ State

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    Using pp collision data corresponding to an integrated luminosity of 8.5 fb-1 recorded by the LHCb experiment at center-of-mass energies of s=7, 8, and 13 TeV, the observation of an excited Bc+ state in the Bc+π+π- invariant-mass spectrum is reported. The observed peak has a mass of 6841.2±0.6(stat)±0.1(syst)±0.8(Bc+) MeV/c2, where the last uncertainty is due to the limited knowledge of the Bc+ mass. It is consistent with expectations of the Bc∗(2S31)+ state reconstructed without the low-energy photon from the Bc∗(1S31)+→Bc+γ decay following Bc∗(2S31)+→Bc∗(1S31)+π+π-. A second state is seen with a global (local) statistical significance of 2.2σ (3.2σ) and a mass of 6872.1±1.3(stat)±0.1(syst)±0.8(Bc+) MeV/c2, and is consistent with the Bc(2S10)+ state. These mass measurements are the most precise to date

    Phase 1 Safety and Immunogenicity Evaluation of ADMVA, a Multigenic, Modified Vaccinia Ankara-HIV-1 B'/C Candidate Vaccine

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    in a modified vaccinia Ankara viral vector. Sequences were derived from a prevalent circulating HIV-1 recombinant form in Yunnan, China, an area of high HIV incidence. The objective was to evaluate the safety and immunogenicity of ADMVA in human volunteers.. Two volunteers mounted antibodies that were able to neutralize clade-matched viruses.ADMVA was well-tolerated and elicited durable humoral and cellular immune responses
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