77 research outputs found

    Spectroscopic characterization of schiff base-copper complexes immobilized in smectite clays

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    Herein, the immobilization of some Schiff base-copper(II) complexes in smectite clays is described as a strategy for the heterogenization of homogeneous catalysts. The obtained materials were characterized by spectroscopic techniques, mostly UV/Vis, EPR, XANES and luminescence spectroscopy. SWy-2 and synthetic Laponite clays were used for the immobilization of two different complexes that have previously shown catalytic activity in the dismutation of superoxide radicals, and disproportionation of hydrogen peroxide. The obtained results indicated the occurrence of an intriguing intramolecular redox process involving copper and the imine ligand at the surface of the clays. These studies are supported by computational calculations

    Unprecedented light induced aggregation of cationic 1,4,5,8-naphthalenediimide amphiphiles

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    Bola amphiphiles from naphthalenediimide (NDI-bas) with quaternary ammonium groups (DC4, DaP, and DaO) display association in solution, as well as, surprisingly, visible light promoted photochromism in concentrated solutions of water, acetonitrile and THF. The photochromism is correlated with an aggregation process that leads to a significant modification of the electronic transitions, resulting in an unusual absorption band distribution that points out to a type of H-aggregation in transverse. This assembly can be reversibly broken up by heating at 70 °C and adding bulk salt (NaBF4). By 1H-NMR spectroscopic analysis of the irradiation/heating cycle the assembly/disassembly process can be followed by the changes in peak width and intensity. These photoinduced aggregates can sensitize dissolved O2 to give singlet oxygen, a surprising observation when it comes to sensitization efficiency for dyes where aggregation usually decreases the sensitization yield. Laser-induced luminescence measurements corroborate the existence of triplet states as phosphorescence was detected, being particularly intense in concentrated THF solutions

    Enxaqueca em 746 pacientes com esclerose múltipla

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    Enxaqueca piora o sofrimento do paciente que tem esclerose múltipla (EM). ID-migraine é uma ferramenta útil para seleção de pacientes com enxaqueca e Migraine Disability Assessment (MIDAS) é um questionário que avalia o impacto da doença. O objetivo do presente estudo foi avaliar a presença e impacto de enxaqueca em pacientes com EM. Métodos: Pacientes diagnosticados com EM e tratados em clínicas especializadas foram convidados a responder um questionário online se também apresentassem cefaleia. Resultados: O estudo incluiu 746 participantes com cefaleia e EM que preencheram completamente as respostas. Foram 625 mulheres e 121 homens, sendo 69% dos pacientes com idade entre 20 e 40 anos. Enxaqueca foi identificada em 404 pacientes (54,1%) e moderado a grave impacto da doença foi observado em 68,3% dos casos. Conclusão: Enxaqueca é uma cefaleia primária frequente e incapacitante relatada por pacientes com EM.Migraine adds to the burden of patients suffering from multiple sclerosis (MS). The ID-migraine is a useful tool for screening migraine, and the Migraine Disability Assessment questionnaire can evaluate disease burden. The aim of the present study was to assess the presence and burden of migraine in patients with MS. Methods: Patients diagnosed with MS attending specialized MS units were invited to answer an online survey if they also experienced headache. Results: The study included 746 complete responses from patients with MS and headache. There were 625 women and 121 men, and 69% of all the patients were aged between 20 and 40 years. Migraine was identified in 404 patients (54.1%) and a moderate-to-high burden of disease was observed in 68.3% of the patients. Conclusion: Migraine is a frequent and disabling type of primary headache reported by patients with MS

    Agricultura urbana agroecológica na perspectiva da promoção da saúde

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    A agricultura urbana tem sido tema de diversas pesquisas no contexto brasileiro e no mundo, principalmente no que diz respeito à geração de trabalho e renda. O presente artigo tem por objetivo sistematizar a experiência do projeto Colhendo Sustentabilidade: práticas comunitárias de segurança alimentar e agricultura urbana (PCS), realizado em Embu das Artes, região metropolitana de São Paulo, durante o período compreendido entre 2008 e 2011, analisando-o sob a ótica da Promoção da Saúde (PS). Foram sujeitos da pesquisa os participantes, os técnicos dos serviços públicos envolvidos e integrantes da equipe técnica do projeto. Os dados foram obtidos através da realização de três oficinas de sistematização, seguidas de outra em que os resultados foram apresentados aos participantes, e também por meio de entrevistas com informantes-chave. Os mesmos foram analisados à luz dos princípios e campos de ação da PS. As conclusões revelaram a agricultura urbana agroecológica (AUA) como ferramenta promotora de saúde por contribuir com o fortalecimento do protagonismo individual e comunitário, empoderamento, criação de ambientes favoráveis à saúde, bem como seu potencial para a multiplicação de "saberes", pelos envolvidos, sobre temas relacionados à geração de renda, saúde e meio ambiente

    Permeability of DOPC bilayers under photoinduced oxidation: Sensitivity to photosensitizer.

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    The modification of lipid bilayer permeability is one of the most striking yet poorly understood physical transformations that follow photoinduced lipid oxidation. We have recently proposed that the increase of permeability of photooxidized 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) bilayers is controlled by the time required by the oxidized lipid species to diffuse and aggregate into pores. Here we further probe this mechanism by studying photosensitization of DOPC membranes by methylene blue (MB) and DO15, a more hydrophobic phenothiazinium photosensitizer, under different irradiation powers. Our results not only reveal the interplay between the production rate and the diffusion of the oxidized lipids, but highlight also the importance of photosensitizer localization in the kinetics of oxidized membrane permeability

    Abundância de gavião-real e gavião-real falso numa área sob impacto de reservatório no Baixo e Médio rio Xingu

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    In the Brazilian Amazon, two monospecific genera, the Harpy Eagle and Crested Eagle have low densities and are classified by IUCN as Near Threatened due to habitat loss, deforestation, habitat degradation and hunting. In this study, we evaluate occurrence of these large raptors using the environmental surveys database from Belo Monte Hydroelectric Power Plant. Integrating the dataset from two methods, we plotted a distribution map along the Xingu River, including records over a 276-km stretch of river. Terrestrial surveys (RAPELD method) were more efficient for detecting large raptors than standardized aquatic surveys, although the latter were complementary in areas without modules. About 53% of the records were obtained during activities of wildlife rescue/flushing, vegetation suppression or in transit. Between 2012 and 2014, four Harpy Eagles were removed from the wild; two shooting victims, one injured by collision with power lines and one hit by a vehicle. Also, seven nests were mapped. The mean distance between Harpy Eagle records was 15 km along the river channel, with a mean of 20 km between nests near the channel, which allowed us to estimate 20 possible pairs using the alluvial forest, riverine forest and forest fragments. Territories of another ten pairs will probably be affected by inundation of the Volta Grande channel, which is far from the main river. The average distance between Crested Eagle records was 16 km along the river channel. The only nest found was 1.3 km away from a Harpy Eagle nest. The remnant forests are under threat of being replaced by cattle pastures, so we recommend that permanently protected riparian vegetation borders (APP) be guaranteed, and that forest fragments within 5 km of the river be conserved to maintain eagle populations. © 2015, Instituto Internacional de Ecologia. All rights reserved
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