Reaction kinetics and mechanismsof organosilicon fungicide flusilazole with sulfate and hydroxyl radicals

[EN] Flusilazole is an organosilane fungicide used for treatments in agriculture and horticulture for control of diseases. The reaction kinetics and mechanism of flusilazole with sulfate and hydroxyl radicals were studied. The rate constant of the radicals with the fungicide were determined by laser flash photolysis of peroxodisulfate and hydrogen peroxide. The results were 2.0 x 10(9) s(-1)M(-1) for the reaction of the fungicide with HO center dot and 4.6 x 10(8) s(-1) M-1 for the same reaction with SO4 center dot- radicals. The absorption spectra of organic intermediates detected by laser flash photolysis of S2O82- with flusilazole, were identified as alpha-aminoallcyl and siloxyl radicals and agree very well with those estimated employing the time-dependent density functional theory with explicit account for bulk solvent effects. In the continuous photolysis experiments, performed by photo-Fenton reaction of the fungicide, the main degradation products were: (bis(4-fluorophenyl)-hydroxy-methylsilane) and the non-toxic silicic acid, diethyl bis(trimethylsilyl) ester, in ten and twenty minutes of reaction, respectively. (C) 2017 Published by Elsevier Ltd.DFM thanks Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET, Argentina) for a graduate studentship. MCG and PC are research members of CONICET, Argentina. This research was supported by grant PICT 2012-2359 from ANPCyT. Financial support for academic interchange by the European Union (IRSES-GA-2010-269128, EnvironBOS) is acknowledged.Mercado, D.; Bracco, LLB.; Arqués Sanz, A.; González, MC.; Caregnato, P. (2018). Reaction kinetics and mechanismsof organosilicon fungicide flusilazole with sulfate and hydroxyl radicals. Chemosphere. 190:327-336. https://doi.org/10.1016/j.chemosphere.2017.09.134S32733619

Desarrollo de fotocatalizadores para la degradación de contaminantes emergentes en aguas

El desarrollo de nuevas tecnologías que permitan eliminar contaminantes emergentes (CE) es de relevancia en la actualidad, ya que la presencia de éstos en aguas superficiales y residuales se ha convertido en un problema medioambiental [1]. La falta de normativa ambiental, estándares de vertimiento y métodos eficaces para su tratamiento nos desafía a investigar alternativas que favorezcan su eliminación

Free radicals produced by the oxidation of gallic acid: An electron paramagnetic resonance study

<p>Abstract</p> <p>Background</p> <p>Gallic acid (3,4,5-trihydroxybenzoic acid) is found in a wide variety of plants; it is extensively used in tanning, ink dyes, as well as in the manufacturing of paper. The gallate moiety is a key component of many functional phytochemicals. In this work electron paramagnetic spectroscopy (EPR) was used to detect the free radicals generated by the air-oxidation of gallic acid.</p> <p>Results</p> <p>We found that gallic acid produces two different radicals as a function of pH. In the pH range between 7-10, the spectrum of the gallate free radical is a doublet of triplets (a^H= 1.00 G, a^H= 0.23 G, a^H= 0.28 G). This is consistent with three hydrogens providing hyperfine splitting. However, in a more alkaline environment, pH >10, the hyperfine splitting pattern transforms into a 1:2:1 pattern (a^H(2) = 1.07 G). Using D₂O as a solvent, we demonstrate that the third hydrogen (<it>i.e</it>. a^H= 0.28 G) at lower pH is a slowly exchanging hydron, participating in hydrogen bonding with two oxygens in <it>ortho </it>position on the gallate ring. The p<it>K</it>_aof this proton has been determined to be 10.</p> <p>Conclusions</p> <p>This simple and novel approach permitted the understanding of the prototropic equilibrium of the semiquinone radicals generated by gallic acid, a ubiquitous compound, allowing new insights into its oxidation and subsequent reactions.</p

FocusDET: Herramienta multimodal para la localización del foco epileptógeno en la epilepsia farmacorresistente

Los pacientes epilépticos con crisis parciales complejas resistentes a tratamiento farmacológico son candidatos a la escisión de la región focal del cerebro que induce dichas crisis. La correcta localización del foco epileptógeno es esencial para considerar la cirugía como posible tratamiento. El objetivo de este trabajo es el desarrollo de una aplicación médica para la localización del foco epileptógeno a partir de datos multimodales. Para el desarrollo de esta nueva herramienta se utiliza GIMIAS, una plataforma de software para la implementación y prototipado de aplicaciones médicas. La nueva herramienta desarrollada, FocusDET, permite llevar a cabo la técnica SISCOM y el análisis de datos EEG-RM f ictal, de imágenes PET y de distintas modalidades de imagen de RM. FocusDET, gracias a su interfaz amigable y a su rapidez de procesamiento, puede ser adecuada para la rutina clínica

Why has not it worked? An empirical application of the extended Burns and Scapens' framework within the implementation of a controlling department

ABSTRACT The aim of this study is to understand the implementation of a controlling department within Bogt and Scapens' framework (2014) as an empirical observation mechanism towards investigating rationalities that prevented its implementation. This study was conducted in a quite successful 63-year old company in the South of Brazil. We hope these results promote practical insight to those interested in supporting changes within this field of organizational environment. There had been two main reasons leading to such work: a lack of equivalent study in the scholarly literature as well as empirical application of Burns and Scapens' framework (2000) reorganized by Bogt and Scapens (2014). Bogt and Scapens (2014), inspired by different logics (Bogt & Scapens, 2012) and in order to revaluate their original framework (2000), suggest the introduction of a fairly important term: rationality. This new element shows the deliberate action from the organizational player - his/her way of thinking. However, even with the introduction of rationales within the model by Bogt and Scapens (2014), rules and routines remain as important elements so that actions take shape. Used methodology consists of an interpretational case study with document analysis, direct observation, and application of semi-structured interviews. Through the interviews and discussions with individuals involved in the study, it can be observed that some rationality resulted in conflicts. Different rationales and the culture of the individual and the organization are relevant aspects observed in the speeches analyzed; all may be factors, which led to the gap within the process of implementation of controlling department in the organization. In addition, time factors suggested in the extended Bogt and Scapens' (2014) framework is of utmost importance for changes must occur gradually

As relações de trabalho dos fisioterapeutas na cidade de Salvador, Bahia

As transformações socioeconômicas decorrentes da reorganização do sistema vigente e da conformação do Estado neoliberal têm conduzido à precarização do mundo do trabalho. O processo de reestruturação produtiva, oriundo do setor industrial, tem acarretado um forte impacto no campo da saúde e, consequentemente, na fisioterapia. Este artigo analisa as relações de trabalho dos fisioterapeutas que atuam em clínicas particulares na cidade de Salvador, correlacionando-as com o processo de reestruturação do mundo do trabalho. Trata-se de um estudo exploratório, de natureza qualitativa, com base no referencial teórico da sociologia do trabalho. Foram realizadas entrevistas semiestruturadas com oito fisioterapeutas. A abordagem utilizada foi a análise de conteúdo por categorias temáticas, previamente identificadas pelos autores, a saber: centralidade do trabalho, conjuntura socioeconômica, precarização do trabalho, formação acadêmica e organização sindical. A análise compreensiva revelou a centralidade que o trabalho ocupa na vida dos fisioterapeutas. Na análise da conjuntura socioeconômica, foram identificados os processos que influenciam a atuação profissional e como eles moldam o perfil do trabalhador. Quanto à precarização do trabalho, foram caracterizados os vínculos empregatícios, as condições de trabalho, a estabilidade e a remuneração. A formação acadêmica foi vinculada à reprodução da lógica do capital, acompanhada pela expansão, sem planejamento e regulação, do Ensino Superior privado. Já a organização sindical mostrou-se distante do fisioterapeuta. A análise das correlações entre forças socioeconômicas que influenciam a prática profissional indicou que as relações de trabalho dos fisioterapeutas entrevistados mostraram-se precárias e instáveis