Comércio de resíduos eletrônicos e Convenção da Basileia : uma análise econômica

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Economia, Administração e Contabilidade, Departamento de Economia, 2012.A transferência de resíduos perigosos de países ricos para países pobres tem sido um traço preocupante da economia política global. O fenômeno é um produto da globalização econômica em um contexto de desigualdades mundiais, e gerou várias respostas políticas, todas elas com alguma fragilidade. A presente dissertação procura analisar, a partir da teoria econômica, a transferência de resíduos eletrônicos de países desenvolvidos para países em desenvolvimento. Nós examinamos as forças que contribuem para essa transferência, bem como a resposta política internacional a ela: a Convenção da Basileia sobre Controle de Movimentos Transfronteiriços de Resíduos Perigosos e seu Depósito. A moldura conceitual adotada envolve conceitos da gestão econômica de resíduos, sendo apresentada uma revisão sistematizada da literatura econômica relativa ao comércio internacional, ao meio ambiente e à economia da poluição. As análises conduzidas surgerem que o problema do resíduo eletrônico está intrinsecamente ligado a fatores econômicos. Visto que a transferência de risco é dinâmica e multifacetada, defendemos que a maneira mais promissora de abordar o problema exige medidas que abrangem uma série de questões, desde o comércio de resíduos até a promoção da produção limpa. ______________________________________________________________________________ ABSTRACTThe displacement of hazardous wastes from richer to poorer countries has been a disturbing feature of the global political economy. The phenomenon is a product of economic globalization in the context of a highly unequal world, and has generated various political responses, all of them with some weaknesses. This dissertation aims to analyze, from the economic theory point of view, the transfer of electronic wastes from developed to developing countries. We look at forces that contribute to that transfer, as well as the international political response to it the Basel Convention on the Transboundary Movements of Hazardous Wastes and their Disposal. The conceptual framework adopted involves concepts of economic waste management, and presents a systematic review of the economic literature on international trade and the environment and economics of pollution. The analyzes conducted indicated that the emergence of the waste trade problem is intricately linked to global economic factors. Because hazard transfer is both dynamic and multifaceted, we argue that the most promising way to address the problem require measures that cover a range of issues, from the trade in wastes to the promotion of clean production

Formação de Formadores: A história das resistências e da educação popular através das imagens murais na América Latina.

Este projeto tem como objetivo geral produzir uma experiência coletiva a partir do encontro entre várias entidades que trabalham a arte mural na América Latina e o Caribe, com o fim de sistematizar e consolidar um material pedagógico sobre as práticas da educação popular no continente. Como exercício de difusão e projeção da proposta, foram realizadas várias ações, entre elas curso de formação de formadores para educadores populares e da rede pública da educação municipal de Foz, em parceria com o SINPREFI, a partir de sua própria demanda à UNILA. Além desse trabalho, em 2018 iniciamos atuação com as crianças da Ocupação Bubas, com oficinas e espaços coletivos de aprendizagem. A intencionalidade é a de explicitar a educação popular como premissa e princípio organizativo para e desde o popular. A referência metodológica é da pesquisa-ação ancorada no materialismo histórico dialético como método que analisa a realidade com vistas a potencializálas

The influence of lens material and lens wear on the removal and viability of staphylococcus epidermidis

Purpose: The aim of this study was to evaluate the influence of lens material and lens wear on the removal capability of Staphylococcus epidermidis. Assessment of viability of remaining adhered bacteria was another goal of this work. Four silicone hydrogel materials (galyfilcon A, balafilcon A, lotrafilcon A, lotrafilcon B) and one conventional hydrogel material (etafilcon A) were assayed. Methods: Detachment studies on S. epidermidis were carried out in a parallel plate flow chamber. Contact lenses (CLs) were fitted to the bottom of the flow chamber and a bacterial suspension was perfused into the system, promoting bacterial adhesion. Afterwards, detachment was stimulated using a multipurpose solution (MPS, ReNu Multiplus®) and the percentage of removed bacteria estimated through microscopic observation and enumeration. Remaining adhered bacteria were stained with propidium iodide (PI) and enumerated in order to assess their viability. Additionally, the worn lenses were observed by confocal laser scanning microscopy (CLSM) to visualize bacterial distribution along the lens surfaces. Results: Bacterial removal was significant ( p < 0.05) for both unworn and worn galyfilcon A and etafilcon A. Galyfilcon A exhibited a detachment percentage of 59.1 and 63.5 while etafilcon A of 62.6 and 69.3, both for unworn and worn lenses, respectively. As far as bacterial viability is concerned, it was found that worn lenses exhibit a superior amount of non-viable bacteria than unworn CLs. Images obtained by CLSM revealed an irregular bacterial distribution for all lens materials. Conclusions: It appears that surface and/or bulk structure of the lens material affects removal of S. epidermidis while CL wear influences their viability.Fundação para a Ciência e a Tecnologia (FCT

Attachment of a clinical strain of Staphylococcus epidermidis to worn and unworn silicone hydrogel contact lenses

Silicone hydrogel contact lenses (CL) are the newest kind of disposable lens commercially available. The copolymerization of silicone elastomers with hydrogels improves the oxygen transmissibility of silicon hydrogel CL when comparing to the conventional hydrogel CL, contributing to a better oxygen supply to the corneal tissues. However, despite this great advantage, this type of CL is usually more hydrophobic and thus is expected to be more prone to microbial colonization. The aim of this work was to study the attachment of a clinical strain of S. epidermidis (9142) to worn and unworn silicone-hydrogel CL through dynamic adhesion assays. The silicone hydrogel CL used in this study were Balafilcon A (Purevision™, Baush&Lomb), Galyfilcon A (Acuvue®Advance™ with Hydraclear, Jonhson&Jonhson Vision Care), Lotrafilcon A (Focus® Night & Day™, Ciba Vision) and Lotrafilcon B (O2Optix™, CibaVision). A conventional hydrogel Etafilcon A (Acuvue®, Jonhson&Jonhson) was also assayed. The worn CL were obtained from a group of human volunteers that used the silicone hydrogels during 1 month and the conventional hydrogel for a period of 15 days, in a daily wear schedule. The attachment assays were performed in a parallel plate flow chamber at laminar flow. The attachment experiments revealed that unworn silicone hydrogels are more prone to bacterial colonization than worn CL. Contact angle measurements, performed with Millipore water, demonstrated that after wear silicone-hydrogel CL become less hydrophobic, which may explain the decrease in the extent of bacterial adhesion to worn CL. In addition the reduction on contact angles formed on this type of lenses may be due to the adsorption of amphiphilic molecules present in the lachrymal tear film such as proteins and lipids. The conventional hydrogel Etafilcon A showed a different behaviour compared with the silicone hydrogels, concerning both hydrophobicity and bacterial attachment. This CL becomes hydrophobic after wear and exhibit an increase in bacterial colonization. This result may be due to a greater loss of the free water content enhancing the interactions between the lens surface and the bacteria

The influence of surface treatment on hydrophobicity, protein adsorption and microbial colonisation of silicone hydrogel contact lenses

Purpose: To evaluate the influence of surface treatment of silicone-hydrogel CL on lens hydrophobicity, protein adsorption and microbial colonisation by studying several silicone hydrogel contact lenses (CL) with and without surface treatment. The lenses used in this study were Balafilcon A, Lotrafilcon A, Lotrafilcon B and Galyfilcon A. A conventional hydrogel CL (Etafilcon A) was also tested. Methods: Hydrophobicity was determined through contact angle measurement using the advancing type technique on air. The type and quantity of proteins adsorbed were assessed through SDS-PAGE and fluorescence spectroscopy, respectively. Microbial colonisation was studied by removing the microbes from the lenses through sonication, and counting the colony-forming units on agar plates. Results: Regarding hydrophobicity, both surface and non-surface-treated silicone hydrogel CL were found to be hydrophobic, and the conventional hydrogel CL was found to be hydrophilic. Concerning protein adsorption, different protein profiles were observed on the several lenses tested. Nevertheless, the presence of proteins with the same molecular weight as lysozyme and lactoferrin was common to all lenses, which is probably related to their abundance in tears. In terms of total protein adsorption, silicone hydrogel CL did not exhibit any differences between themselves. However, the conventional hydrogel Etafilcon A adsorbed a larger amount of proteins. Regarding microbial colonisation, Balafilcon A exhibited the greatest amount of colonising microbes, which can be due to its superior hydrophobicity and higher electron acceptor capacity. Conclusion: This study suggests that silicone hydrogel lenses adsorb a lower amount of proteins than the conventional hydrogel lenses and that this phenomenon is independent of the presence of surface treatment. Concerning microbial colonisation, the surface treated Balafilcon A, exhibited a greater propensity, a fact that may compromise the lens wearer’s ocular health.Fundação para a Ciência e a Tecnologia (FCT

The effect of octylglucoside and sodium cholate in Staphylococcus epidermidis and Pseudomonas aeruginosa adhesion to soft contact lenses

Purpose. In this study, the effect of the natural surfactants octylglucoside and sodium cholate in inhibiting Staphylococcus epidermidis and Pseudomonas aeruginosa adhesion to conventional and silicone-hydrogel contact lenses (CL) was assessed. Hydrophobicity was also evaluated to conditioned and nonconditioned CL. Methods. The inhibiting effect of the tested surfactants was determined through “in vitro” adhesion studies to conditioned and nonconditioned CL followed by image acquisition and cell enumeration. Hydrophobicity was evaluated through contact angle measurements using the advancing type technique on air. Results. Sodium cholate exhibits a very low capability to inhibit microbial adhesion. Conversely, octylglucoside effectively inhibited microbial adhesion in both types of lenses. This surfactant exhibited an even greater performance than a multipurpose lens care solution used as control. Octylglucoside was the only tested surfactant able to lower the hydrophobicity of all CL, which can explain its high performance. Conclusions. The results obtained in this study point out the potential of octylglucoside as a conditioning agent to prevent microbial colonization.Portuguese Foundation for Science and Technology (FCT