Relatos da prevalência das parasitoses intestinais no Brasil são pontuais e têm sido descritos em diferentes populações, tornando difícil um diagnóstico abrangente. Visando estudar a variação em 35 anos da prevalência de enteroparasitoses em escolares de Caxias do Sul, RS, foram avaliados 9.787 exames parasitológicos de fezes realizados por centrífugo-sedimentação. Resultaram positivas 5.655 (58%) amostras sendo mais prevalente a infestação por Ascaris lumbricoides (47%), Trichuris trichiura (36%), Enterobius vermicularis (8%) e os protozoários: Giardia lamblia (24%) e Entamoeba coli (20%). A prevalência geral diminuiu de 89% para 37%, com um decréscimo médio de 1,4% ao ano. Houve redução na prevalência de Ascaris lumbricoides de 61 para 26% e de Trichuris trichiura de 38 a 18%. Para Giardia lamblia não houve alteração significativa. A prevalência de Entamoeba coli cresceu de 29 a 46%. Os decréscimos obtidos na prevalência dos helmintos são provavelmente devidos às melhorias da infra-estrutura e às ações formativas desenvolvidas nas escolas.
This study aims to evaluate the influence of pro-oxidant additive and accelerated aging on the degradation of polyethylene (PE) samples in simulated soil, in accordance with ASTM G160-03. Films of polyethylene with and without pro-oxidant additive were studied, before and after 72 hours of accelerated aging. The films were initially characterized by analyses of Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) (to evaluate the Carbonyl Index (CI)). The films were exposed for 30, 60 and 90 days in simulated soil, with controlled moisture and soil pH. The results showed the degradation of polyethylene films through an increase of CI in samples with additive and accelerated aging after 30 days of exposure, and a decrease, after 60 and 90 days, indicating the uptake of material oxidation by-products by microorganisms. The polyethylene films without pro-oxidant additive after accelerated aging showed greater structural and surface modifications, as compared to films with the additive.
This study was carried out over a 2-year period (2001 and 2002) with the aim of identifying the fungal population in the aerosol of the Southern city of Caxias do Sul, RS, Brazil. Sampling was performed using Hirst's non-viable volumetric method. Our results show the presence of a large number of fungal spore types, a total of 41. Three groups were predominant: Deuteromycotina, Ascomycotina and Basidiomycotina. In 2001, Deuteromycotina taxa represented 44.61% of the total annual spore counts, with the largest concentration occurring in the fall (58,637 spores); in 2002, it represented 40.03% of the total annual spore counts, and the largest concentration was obtained in the summer (68,317 spores). Ascomycotina was present at the same level (24.5%) in both years of sampling, and the highest concentrations were found out in the summer (2001: 42,183 spores; 2002: 29,461 spores). Basidiomycotina represented 22.37% of the total annual spore counts in 2001, and 20.41% in 2002, with the largest concentrations found in the summer (2001: 35,988 spores; 2002: 30,212 spores). The most frequent fungi found during the study period were Cladosporium, Coprinus, Leptosphaeria, Aspergillus/ Penicillium and Ganoderma. Permanent aerobiological monitoring would be necessary to detect associated environmental variations.
Invasive aspergillosis (IA) seems to be an emerging condition in intensive care units (ICUs). However, little attention has been given to the role of environmental factors that could increase the risk for IA in the ICU. The objective of this study was to determine the concentration of airborne fungi in three Brazilian ICUs, in an attempt to correlate fungal burden with the frequency of Aspergillus spp isolation from clinical samples of patients hospitalised in these units. During a 1-year period we quantitatively evaluated the presence of fungi in the air of three ICUs in Porto Alegre, Brazil. The quantity of fungi was correlated with environmental factors. Only one of the ICUs studied showed equal concentrations of Aspergillus conidia in the indoor air, in comparison with the outdoor environment. All cases of Aspergillus colonisation and IA cases observed during the study occurred in that particular ICU. Environmental factors have a direct influence on fungal spore concentration in the air in ICUs, as well as air filtration systems in air conditioners. Fungal contamination of the indoor air may influence the frequency of AI in ICU patients.
Resumo: O poli(cloreto de vinila) (PVC) é um dos polímeros utilizado no campo das embalagens e no setor calçadista, e, em função da sua aplicação diversificada, apresenta elevados percentuais em aterros domésticos e industriais. É um polímero amorfo podendo apresentar diferentes teores de plastificante e outros aditivos responsáveis pela sua estabilização, os quais podem influenciar no tempo de vida útil e nas propriedades do produto final. Este trabalho apresenta o estudo da degradação química e biológica de filmes de poli(cloreto de vinila) flexível (PVC-f), no aterro sanitário São Giácomo, na cidade de Caxias do Sul/RS, antes e após 330 dias de disposição. As amostras de PVC-f antes e após a disposição no aterro sanitário foram avaliadas por análise térmica (TGA), estrutural (FT-IR) e morfológica (MEV e MO). Observou-se que as amostras de PVC-f dispostas no aterro sanitário (PVC-fa), apresentam um único evento de perda de massa, em relação ao PVC-f não degradado ou virgem (PVC-fv), além de um maior % de perda de massa e de mudanças estruturais. Nas amostras de PVC-fa foram observadas modificações morfológicas importantes para descrever os fenômenos de degradação como erosão da superfície, bioerosão, que propiciaram a ação das leveduras, bactérias e fungos presentes no meio no polímero aterrado. Palavras-chave: Degradação, PVC, aterro sanitário, microrganismos, técnicas microscópicas. Biological Degradation of PVC in Landfill and Microbiological EvaluationAbstract: The poly (vinyl chloride) (PVC) is one of the polymers used in the field of packing materials and footwear sector, and due its diversified applications, it has presented in a high percentage of domestic and industrial landfills It is an amorphous polymer and may present different levels of plasticizer and other additives responsible for its stabilization, which can influence the lifetime and the properties of the final product. This work presents the study of the chemical and biological degradation of poly (vinyl chloride) flexible (PVC-f) films, at São Giácomo landfill, in Caxias do Sul city after 330 days of disposition. The samples of PVC-f were evaluated by thermal (TGA), structural (FT-IR) and morphological (MEV and MO) analysis after disposition. Samples of PVC-f disposed to landfill (PVC-fa) showed a single event of weight loss, when compared to PVC-f undegraded or virgin (PVC-fv), besides a higher weight loss and structural changes. In the PVC-fa samples, morphological modifications were observed, which are very important to describe the degradation phenomenon as superficial erosion and bioerosion, which propitiated the action of the yeast, bacteria and fungi present in the environment on the disposed polymer. Keywords: Degradation/biodegradation, PVC, landfill, microorganism, microscopy techniques. IntroduçãoSegundo Chiellini e Solaro [1] , os materiais poliméricos apresentam baixo custo e propriedades características, tais como leveza e praticidade, o que leva a maioria dos usuários, descartá-los sem controle ou inadequadamente, ameaçando ...
Composites consisting of waste cotton yarn (CF) from the textile industry and postconsumer expanded polystyrene (EPS) was followed during 90 days of exposure in simulated soil. The mechanical properties, morphologies and chemical natures of the composites were determined before and after exposure in simulated soil. The composites were made using a single-screw extrusion, a twin-screw extrusion and injection molding. The composites showed an increase of the mechanical properties nearly 50% in relation to the recycled expanded polystyrene (rEPS). After exposure in simulated soil the composites presented losses of mechanical properties. Evidence of the oxidation of the samples was demonstrated by the increase in the values of the carbonyl index after 30 days of exposure in simulated soil. Changes in the color of the surface of the sample were observed after 90 days of exposure and are due to the fungi and bacteria colonization on the surface.
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