955 resultados para Socio-Environmental image


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In order to study the environmental contamination by Toxocara spp. eggs in a rural community from the Pontal do Paranapanema region, São Paulo State, Brazil, soil samples from 31 out of 121 plots were collected in eight different places on each house. The samples were submitted to flotation technique in sodium nitrate (d = 1.20g/cm³). Eggs of Toxocara spp. were recovered in nine (29.03%) out of the 31 plots. At least one dog was registered in 27 of the 31 plots examined (87.1%) and at least one cat in 17 (54.84%). The number of pets per plot ranged from one to six (mean of 2.3) for dogs and one to 14 (mean of 1.29) for cats. In 16 plots (51.61%), the presence of both dogs and cats was observed. There was no relation between the presence of pets in the plots and soil contamination (p > 0.05). However, the environmental contamination by Toxocara spp. eggs associated to the poor conditions of the inhabitants may be an important risk factor for the human population to ocular or visceral larva migrans.

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Cryptococcus neoformans is the major cause of fungal meningitis, a potentially lethal mycosis. Bird excreta can be considered a significant environmental reservoir of this species in urban areas, thirty-three samples of pigeon excreta were collected within the city of Vitoria, Brazil. Cryptococcus neoformans was isolated and identified using standard biochemical assays in ten samples. PCR amplification with primer M13 and orotidine monophosphate pyrophosphorylase (URA5) gene-restriction fragment length polymorphism (RFLP) analysis discerned serotypes and genotypes within this species. All isolates were serotype A (C. neoformans var. grubii) and genotype VNI. The two alternative alleles a and α at the mating type locus were determined by PCR amplification and mating assays performed on V8 medium. All isolates were MAT α mating type but only 50% were able to mate in vitro with the opposite mating type MAT a tester strains (JEC20, KN99a and Bt63). This study adds information on the ecology and molecular characterization of C. neoformans in the Southeast region of Brazil.

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The use of buffers to maintain the pH within a desired range is a very common practice in chemical, biochemical and biological studies. Among them, zwitterionic N-substituted aminosulfonic acids, usually known as Good’s buffers, although widely used, can complex metals and interact with biological systems. The present work reviews, discusses and updates the metal complexation characteristics of thirty one commercially available buffers. In addition, their impact on biological systems is also presented. The influences of these buffers on the results obtained in biological, biochemical and environmental studies, with special focus on their interaction with metal ions, are highlighted and critically reviewed. Using chemical speciation simulations, based on the current knowledge of the metal–buffer stability constants, a proposal of the most adequate buffer to employ for a given metal ion is presented.

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This work aims to evaluate the feasibility of using image-based cytometry (IBC) in the analysis of algal cell quantification and viability, using Pseudokirchneriella subcapitata as a cell model. Cell concentration was determined by IBC to be in a linear range between 1 × 105 and 8 × 106 cells mL−1. Algal viability was defined on the basis that the intact membrane of viable cells excludes the SYTOX Green (SG) probe. The disruption of membrane integrity represents irreversible damage and consequently results in cell death. Using IBC, we were able to successfully discriminate between live (SG-negative cells) and dead algal cells (heat-treated at 65 °C for 60 min; SG-positive cells). The observed viability of algal populations containing different proportions of killed cells was well correlated (R 2 = 0.994) with the theoretical viability. The validation of the use of this technology was carried out by exposing algal cells of P. subcapitata to a copper stress test for 96 h. IBC allowed us to follow the evolution of cell concentration and the viability of copper-exposed algal populations. This technology overcomes several main drawbacks usually associated with microscopy counting, such as labour-intensive experiments, tedious work and lack of the representativeness of the cell counting. In conclusion, IBC allowed a fast and automated determination of the total number of algal cells and allowed us to analyse viability. This technology can provide a useful tool for a wide variety of fields that utilise microalgae, such as the aquatic toxicology and biotechnology fields.

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The development and application of a polyaniline/carbon nanotube (CNT) cyclodextrin matrix (PANI-β-CD/MWCNT)-based electrochemical sensor for the quantitative determination of the herbicide 4-chloro-2-methylphenoxyacetic acid (MCPA) and its main transformation product 4-chloro-2-methylphenol in natural waters are described. A simple cyclic voltammetry-based electrochemical methodology, in phosphate buffer solution at pH 6.0, was used to develop a method to determine both MCPA and 4-chloro-2-methylphenol, without any previous extraction or derivatization steps. A linear concentration range (10 to 50 μmol L−1) and detection limits of 1.1 and 1.9 μmol L−1, respectively, were achieved using optimized cyclic voltammetric parameters. The proposed method was successfully applied to the determination of MCPA and 4-chloro-2-methylphenol in natural water samples with satisfactory recoveries (94 to 107 %) and in good agreement with the results obtained by an established high-performance liquid chromatography technique, no significant differences being found between the methods. Interferences from ionic species and other herbicides used for broad-leaf weed control were shown to be small. The newly developed methodology was also successfully applied to MCPA photodegradation environmental studies.

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Dissertação apresentada para obtenção do Grau de Mestre em Engenharia Informática pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia

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The environmental contamination by geohelminths represents a world public health problem and has been well documented by several authors. However, few papers describe the presence of such contamination in saline soils of coastal beaches. A study was performed on the beaches of the municipality of Santos in the period between May 2004 to April 2005 with the aim of determining the degree of contamination, and the correlation between contamination level and seasonal conditions and characteristics of the environment. Of the 2,520 samples analyzed, 18.2% (458) were contaminated, 32.3% (148) of which were localized in children's recreational areas (playgrounds). The parasite profile found in the analyzed samples indicated the presence of several zoonotic parasites: Ancylostoma larvae (82.5%), Toxocara sp. eggs (59.4%), Ancylostomidae-like eggs (37.1%), coccid oocysts (13.5%), Trichostrongylus sp. eggs and larvae, Ascaris lumbricoides eggs, (11.6%), Entamoeba sp. cysts (10.0%), Strongyloides sp. (4.8%), several free nematoids and some non-identified parasitic structures (3.3%). It was established that the highest frequency of parasitic structures occurred in the months between May and October 2004, and from February to March 2005. An increase in the diversity of parasitic forms was documented in the months between February to December 2004 and from January to April 2005, these periods having the highest rainfall.

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Este estudo tem como finalidade analisar a possibilidade de implementação e integração do sistema de gestão da responsabilidade social numa empresa de engenharia e construção, de acordo com a norma NP 4469-1 (2008). Um dos objetivos deste trabalho é explorar uma das atividades fundamentais para o crescimento da economia: a construção. Esta funciona como barómetro da economia nacional, ou seja, movimenta vários setores importantes na sua cadeia de produção, contribuindo na criação de riqueza como também de emprego. Como consequência das mudanças na economia nos últimos anos, o comércio nacional transformou-se em comércio globalizado, tendo como mercado não só um país mas o mundo inteiro. As empresas veem isso como um desafio, independentemente da sua dimensão. A redução de custos e a diferenciação não podem ser a única fonte de competitividade. A recente situação de instabilidade económica mundial impulsiona as empresas a inovarem na sua imagem para com os stakeholders e, assim, garantir o seu desenvolvimento e sustentabilidade financeira. A temática da Responsabilidade Social Empresarial (RSE) surgiu da necessidade de existir um espírito empresarial responsável, ao encontro do conceito de desenvolvimento sustentável (Baylis e Smith, 2005). Apesar da ampla divulgação da noção de responsabilidade social das empresas, não se verifica, no entanto, uma definição exata da mesma, pois o tema tem sido abordado de diversas formas e tem dividido opiniões ao longo dos anos. A responsabilidade social é, assim, um fruto da gestão das organizações e das profundas críticas sociais, legais, éticas e económicas, inspiradas nos parâmetros da obtenção de valor social (Parra, 2003). A sustentabilidade revela uma mudança de paradigma do mundo empresarial, na medida em que as empresas devem adotar práticas socialmente responsáveis, que integrem de forma voluntária as preocupações ambientais, sociais e económicas no desenvolvimento das suas atividades operacionais e das suas interações com as partes interessadas.

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Dissertação para obtenção do Grau de Doutor em Ambiente, pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia

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Thesis submitted to the Instituto Superior de Estatística e Gestão de Informação da Universidade Nova de Lisboa in partial fulfillment of the requirements for the Degree of Doctor of Philosophy in Information Management – Geographic Information Systems

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Antes de tudo terei que referir o que qu ero dizer com modelo sacio-antropológico, sobretudo qu e é um modelo. Definir modelo é muito difícil poi s pode significar muita co isa: aquilo que serve ou deve servir de obj ecto de imitação para fazer ou reproduzir qualquer coi sa ; pode, ainda, ser um cânon, um ensaio de explicação da chamada estrutura, poi s vivemos num mundo de es truturas organizadas com as qu ai s construímos e apercebemos es te mesmo mundo. Na investigação da dita realidade soc ia l, passamos desta para o modelo e vice -versa . Este contínuo vai-vem nun ca deve ser interrompido. O modelo imita e representa, mas nun ca co nstitui, um elemento de controlo da investigação , é um instrumento de comparação e, ainda, pode significar uma forma de verificação da so lidez e da própria vida de uma dada es trutura. Em Hi stória, por exemplo, Braudel afirma que pode se r hipóteses de explicação so lidamente vinculado, segundo a forma de equação ou da função. Daí o facto de os modelos poderem ser considerados como si stemas de explicação, variando até o infi nito : simples ou complexos, físicos ou abstrac tos, qualitativos ou quantitativos, estatísticos ou dinâmi co s, mecâni cos ou estatísticos.

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Hard‐rock watersheds commonly exhibit complex geological bedrock and morphological features. Hydromineral resources have relevant economic value for the thermal spas industry. The present study aims to develop a groundwater vulnerability approach in Caldas da Cavaca hydromineral system (Aguiar da Beira, Central Portugal) which has a thermal tradition that dates back to the late 19th century, and contribute to a better understanding of the hydrogeological conceptual site model. In this work different layers were overlaid, generating several thematic maps to arrive at an integrated framework of several key‐sectors in Caldas da Cavaca site. Thus, to accomplish a comprehensive analysis and conceptualization of the site, a multi‐technical approach was used, such as, field and laboratory techniques, where several data was collected, like geotectonics, hydrology and hydrogeology, hydrogeomorphology, hydrogeophysical and hydrogeomechanical zoning aiming the application of the so‐called DISCO method. All these techniques were successfully performed and a groundwater vulnerability to contamination assessment, based on GOD‐S, DRASTIC‐Fm, SINTACS, SI and DISCO indexes methodology, was delineated. Geographical Information Systems (GIS) technology was on the basis to organise and integrate the geodatabases and to produce all the thematic maps. This multi‐technical approach highlights the importance of groundwater vulnerability to contamination mapping as a tool to support hydrogeological conceptualisation, contributing to better decision‐making of water resources management and sustainability.

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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.