25 research outputs found

    Identification of hemodynamically stable patients with acute pulmonary embolism at high risk for death: external validation of different models

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    Background: The optimal strategy for identification of hemodynamically stable patients with acute pulmonary embolism (PE) at risk for death and clinical deterioration remains undefined. Objectives: We aimed to assess the performances of currently available models/scores for identifying hemodynamically stable patients with acute, symptomatic PE at risk of death and clinical deterioration. Methods: This was a prospective multicenter cohort study including patients with acute PE (NCT03631810). Primary study outcome was in-hospital death within 30 days or clinical deterioration. Other outcomes were in-hospital death, death, and PE-related death, all at 30 days. We calculated positive and negative predictive values, c-statistics of European Society of Cardiology (ESC)-2014, ESC-2019, Pulmonary Embolism Thrombolysis (PEITHO), Bova, Thrombo-embolism lactate outcome study (TELOS), fatty acid binding protein, syncope and tachicardia (FAST), and National Early Warning Scale 2 (NEWS2) for the study outcomes. Results: In 5036 hemodynamically stable patients with acute PE, positive predictive values for the evaluated models/scores were all below 10%, except for TELOS and NEWS2; negative predictive values were above 98% for all the models/scores, except for FAST and NEWS2. ESC-2014 and TELOS had good performances for in-hospital death or clinical deterioration (c-statistic of 0.700 and 0.722, respectively), in-hospital death (c-statistic of 0.713 and 0.723, respectively), and PE-related death (c-statistic of 0.712 and 0.777, respectively); PEITHO, Bova, and NEWS2 also had good performances for PE-related death (c-statistic of 0.738, 0.741, and 0.742, respectively). Conclusion: In hemodynamically stable patients with acute PE, the accuracy for identification of hemodynamically stable patients at risk for death and clinical deterioration varies across the available models/scores; TELOS seems to have the best performance. These data can inform management studies and clinical practice

    Experimental assessment of heavy metal extraction from contaminated italian harbour sediment by rhamnolipid

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    This study presents the results of laboratory scale experimental tests of contaminants extraction from marine sediment slurries. The sediment was collected in a harbour situated in a high density industrial area, characterized by a high pollution level of heavy metals. The contamination of the sediment used in this experimentation was artificially increased to reach final values of 1250 mg/Kg of Cu and 2026 mg/Kg of Pb. The objective of this study was to investigate the effectiveness of selected chelating agents (Rhamnolipid, EDDS and Acid Citric) in heavy metals removal from contaminated sediments. The investigated parameters during the washing tests were the chelants concentration and the overall washing time. To evaluate sediments characteristics COD and acid digestion were performed, while TOC and heavy metal’s concentration were determined on the solutions extracted. Results show that the use of EDDS and EDTA allows the reaching of good extraction efficiencies (up to 95 %) unlike lower removal rates reached by the Acid Citric and Rhamnolipid, probably due to very low values of constants of the corresponding metal-additive complexes. Finally, major cations, above all Fe and Ca, were found to be strong competitors with the target metals for the metal-ligand complexes formation

    Enhancement of biomass speciation in step sludge recirculation activated sludge system by the use of submerged membranes

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    In this work the performances of the Step Sludge Recirculation (SSR) activated sludge process were improved. The process is made up of an anoxic stage for the denitrification and four aerobic stages for the nitrification. The conventional system was compared with system where the secondary clarifier was substituted by a submerged membrane module. Two different types of flat sheet membrane were fitted into the membrane module. The performances were measured by means of a microscopic observation of the microfauna and other physical-chemical analysis. The main objective of the work was to optimize the process in order to obtain a maximum in the removal of ammoniacal nitrogen. For the all tested systems, the activated sludge presented high microfauna density although the system with submerged membranes presented a higher efficiency in nitrogen removal. These results were however affected by the inhibition of nitrification provoked by free ammonia. No significant fouling was observed for the membranes

    Application of membrane technology in activated sludge process

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    In this work the performances of the Step Sludge Recirculation (SSR) activated sludge process were improved. The process consists of an anoxic stage where denitrification occurs and four aerobic stages where the nitrifications occur. The conventional system was compared with a second system where the secondary clarifier was substituted by a submerged membrane module. Two different types of flat sheet membrane were fitted into the membrane module. The performances were measured by means of a microscopic observation of the microfauna in the activated sludge and other physical-chemical analysis such as solids, TOC, O.U.R. test, total nitrogen, ion determination. The main objective of the work was to optimize the process in order to obtain a maximum in the removal of ammoniacal nitrogen

    Selectivity of glyphosate in tank mixtures for RR soybean in sequential applications with mixtures only in the first or second application Seletividade de glyphosate em misturas em tanque para soja RR em aplicações sequenciais com mistura apenas na primeira ou na segunda aplicação

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    Tank mixtures among herbicides of different action mechanisms might increase weed control spectrum and may be an important strategy for preventing the development of resistance in RR soybean. However, little is known about the effects of these herbicide combinations on soybean plants. Hence, two experiments were carried out aiming at evaluating the selectivity of glyphosate mixtures with other active ingredients applied in postemergence to RR soybean. The first application was carried out at V1 to V2 soybean stage and the second at V3 to V4 (15 days after the first one). For experiment I, treatments (rates in g ha-1) evaluated were composed by two sequential applications: the first one with glyphosate (720) in tank mixtures with cloransulam (30.24), fomesafen (125), lactofen (72), chlorimuron (12.5), flumiclorac (30), bentazon (480) and imazethapyr (80); the second application consisted of isolated glyphosate (480). In experiment II, treatments also consisted of two sequential applications, but tank mixtures as described above were applied as the second application. The first one in this experiment consisted of isolated glyphosate (720). For both experiments, sequential applications of glyphosate alone at 720/480, 960/480, 1200/480 and 960/720 (Expt. I) or 720/480, 720/720, 720/960 and 720/1200 (Expt. II) were used as control treatments. Applications of glyphosate tank mixtures with other herbicides are more selective to RR soybean when applied at younger stages whereas applications at later stages might cause yield losses, especially when glyphosate is mixed with lactofen and bentazon.<br>A mistura em tanque entre herbicidas de diferentes mecanismos de ação pode aumentar o espectro de controle dos tratamentos e consistir de uma nova estratégia de controle de plantas daninhas na cultura da soja RR. No entanto, pouco se sabe sobre os efeitos destas misturas nas plantas de soja. Dessa forma, foram realizados dois experimentos com o objetivo de avaliar a seletividade do glyphosate isolado ou em misturas com outros princípios ativos aplicados em pósemergência à soja RR. Nos experimentos I e II os tratamentos foram constituídos por aplicações seqüenciais de herbicidas, sendo a primeira realizada no estádio V1 a V2 da soja e a segunda no estádio V3 a V4 (15 dias após a primeira). Para o experimento I, os tratamentos testados (doses em g ha¹) foram compostos por duas aplicações sequenciais: a primeira com glyphosate (720) em mistura em tanque com cloransulam (30.24), fomesafen (125), lactofen (72), chlorimuron (12.5), flumiclorac (30), bentazon (480) e imazethapyr (80); a segunda aplicação consistiu de glyphosate (480) isolado. No segundo experimento, os tratamentos também foram compostos por duas aplicações seqüenciais, mas as misturas em tanque descritas anteriormente foram aplicadas na segunda aplicação, sendo a primeira composta de glyphosate (720) isolado. Ambos experimentos foram compostos ainda por aplicações seqüenciais de glyphosate isolado nas doses 720/480, 960/480, 1200/480 e 960/ 720 (Experimento I) ou 720/480, 720/720, 720/960 e 720/1200 (Experimento II) como testemunhas. Aplicações de misturas de glyphosate com outros herbicidas apresentam maior seletividade para soja RR quando aplicadas em estádios mais novos, enquanto que aplicações das misturas em estádios mais tardios podem provocar perdas de produtividade, especialmente quando glyphosate é misturado à lactofen e bentazon

    Selectivity of glyphosate tank mixtures for RR soybean

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    An active ingredients mixture of different action mechanisms is an essential tool to prevent or manage areas with resistant weeds. However, it is important that such a mixture provides adequate selectivity to the crop. The aim of this work was to evaluate glyphosate selectivity to glyphosate-resistant (RR) soybean, and also verify if there is selectivity in mixtures with other active ingredients applied postemergence aimed at new control strategies, which might be used in RR soybean cultivation. The herbicides and respective rates (g ha-1) evaluated were: glyphosate (720, 960, 1,200, and 1,440), and the mixtures of glyphosate (960) with cloransulam-methyl (30.24), fomesafen (125), lactofen (72), chlorimuron-ethyl (12.5), flumiclorac-pentyl (30), bentazon (480), or imazethapyr (80). All treatments were applied in postemergence when the soybean crop was at V2 to V3 stage. Treatments with glyphosate or in mixtures with postemergent herbicides showed visual effects of phytotoxicity when applied to the glyphosate-resistant soybean. Effects such as reduction in plant height, crop closure, number of pods per plant, and hundred grain weight could be observed. However, the effects related to plant development were mostly transient and did not persist during the crop cycle. Among the studied treatments, only the mixture of glyphosate and lactofen was not selective to the crop, promoting negative effects on most characteristics analyzed and consequently reducing grain yield.A mistura de ingredientes ativos de diferentes mecanismos de ação é uma ferramenta essencial para prevenir ou manejar áreas com plantas daninhas resistentes. No entanto é importante que tais associações forneçam adequada seletividade para a cultura. O objetivo deste trabalho foi avaliar a seletividade do glyphosate a soja RR, e verificar também, se existe seletividade a misturas com outros ingredientes ativos, aplicados em pós-emergência, visando novas estratégias de controle que poderão ser empregadas no cultivo da soja RR. Os herbicidas e respectivas doses (g ha-1) avaliadas foram: glyphosate isolado (720, 960, 1.200 e 1.440) e as misturas de glyphosate (960) com cloransulam-methyl (30,24), fomesafen (125), lactofen (72), chlorimuron-ethyl (12,5), flumiclorac-pentyl (30), bentazon (480) e imazethapyr (80). Todos os tratamentos foram aplicados em dose única em pós-emergência quando a soja estava no estádio V2 a V3. Tratamentos com glyphosate isolado ou em mistura com herbicidas pós-emergentes aplicados em dose única promoveram efeitos visuais de fitointoxicação quando aplicados na soja resistente ao glyphosate. Efeitos como redução na altura das plantas, no fechamento da cultura, no número de vagens por planta e na massa de cem grãos puderam ser observados. Entretanto, os efeitos relatados ao desenvolvimento das plantas foram na sua maioria transientes, não persistindo durante todo ciclo da cultura. Dentre os tratamentos estudados, somente a mistura entre glyphosate e lactofen não apresentou seletividade à cultura, promovendo efeitos negativos na maioria das características estudadas e consequentemente reduzindo a produtividade de grãos
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