Evidências da relação entre a evolução da gestão ambiental e a adoção de práticas de green supply chain management no setor eletroeletrônico brasileiro

Na pesquisa apresentada, teve-se como objetivo verificar se a evolução da gestão ambiental se relaciona positivamente com a adoção de práticas de green supply chain management (GSCM) por empresas do setor eletroeletrônico do Brasil. Para fazer frente ao objetivo exposto, foi realizada uma pesquisa quantitativa, por meio de um levantamento survey, com cem empresas do setor eletroeletrônico brasileiro. Os dados coletados foram processados por meio de técnicas estatísticas descritivas, análise fatorial exploratória e modelagem de equações estruturais. Os resultados mais importantes da pesquisa foram: na amostra, práticas de GSCM orientadas para a recuperação dos investimentos das empresas, como a revenda de materiais inservíveis e outros resíduos, além da adequação à legislação e à auditoria ambiental, obtiveram médias elevadas; e a hipótese de pesquisa (H1) foi confirmada e considerada estatisticamente válida, indicando que a evolução da gestão ambiental influencia a adoção de práticas de GSCM.

Induction of tolerogenic vs immunogenic dendritic cells (DCs) in the presence of GM-CSF is regulated by the strength of signaling from monophosphoryl lipid A (MPLA) in association with glutathione and fetal hemoglobin gamma-chain.

Previous studies showed a fetal sheep liver extract (FSLE), in association with monophosphoryl lipid A, MPLA (a bioactive component of lipid A of LPS), could interact to induce the development of dendritic cells (DCs) which regulated production of Foxp3+ Treg. This interaction was associated with an altered gene expression both of distinct subsets of TLRs and of CD200Rs. Prior studies had suggested that major interacting components within FSLE were gamma-chain of fetal hemoglobin (Hgbgamma) and glutathione (GSH). We investigated whether differentiation/maturation of DCs in vitro in the presence of either GM-CSF or Flt3L to produce preferentially either immunogenic or tolerogenic DCs was itself controlled by an interaction between MPLA, GSH and Hgbgamma. At low (approximately 10 microg/ml) Hgbgamma concentrations, DCs developing in culture with GSH and MPLA produced optimal stimulation of allogeneic CTL cell responses in vitro (and enhanced skin graft rejection in vivo). At higher concentrations (>40 microg/ml Hgbgamma) and equivalent concentrations of MPLA and GSH, the DCs induce populations of Treg which can suppress the induction of allogeneic CTL and graft rejection in vivo. These different populations of DCs express different patterns of mRNAs for the CD200R family. Addition of anti-TLR or anti-MD-1 mAbs to DCs developing in this mixture (Hgbgamma+GSH+MPLA), suggests that one effect of (GSH+Hgbgamma) on MPLA stimulation may involve altered signaling through TLR4.

Illuminating the detection chain of bacterial bioreporters.

Engineering bacteria for measuring chemicals of environmental or toxicological concern (bioreporter bacteria) has grown slowly into a mature research area. Despite many potential advantages, current bioreporters do not perform well enough to comply with environmental detection standards. Basically, the reasons for this are the lack of engineering principles in the detection chain in the bioreporters. Here, we dissect critical steps in the detection chain and illustrate how bioreporter design could be improved by mutagenizing specificity and selectivity of the sensing and regulatory proteins, by newer expression strategies and application of different signalling networks. Furthermore, we describe how redesigning bioreporter assays with respect to pollutant transport into the cells and application of other detection devices can decrease detection limits and increase the speed of detection.

Code des mines et mineurs : manuel de législation, d'administration, de doctrine et de jurisprudence concernant les mines, minières et carrières,... / par L.-J.-D. Féraud-Giraud,...

Collection : Petite encyclopédie juridique ; 40-42

Bayesian Markov chain Monte Carlo inversion of geophysical data for the purpose of estimating the hydraulic properties of the unsaturated zone

Ground-penetrating radar (GPR) has the potential to provide valuable information on hydrological properties of the vadose zone because of their strong sensitivity to soil water content. In particular, recent evidence has suggested that the stochastic inversion of crosshole GPR data within a coupled geophysical-hydrological framework may allow for effective estimation of subsurface van-Genuchten-Mualem (VGM) parameters and their corresponding uncertainties. An important and still unresolved issue, however, is how to best integrate GPR data into a stochastic inversion in order to estimate the VGM parameters and their uncertainties, thus improving hydrological predictions. Recognizing the importance of this issue, the aim of the research presented in this thesis was to first introduce a fully Bayesian inversion called Markov-chain-Monte-carlo (MCMC) strategy to perform the stochastic inversion of steady-state GPR data to estimate the VGM parameters and their uncertainties. Within this study, the choice of the prior parameter probability distributions from which potential model configurations are drawn and tested against observed data was also investigated. Analysis of both synthetic and field data collected at the Eggborough (UK) site indicates that the geophysical data alone contain valuable information regarding the VGM parameters. However, significantly better results are obtained when these data are combined with a realistic, informative prior. A subsequent study explore in detail the dynamic infiltration case, specifically to what extent time-lapse ZOP GPR data, collected during a forced infiltration experiment at the Arrenaes field site (Denmark), can help to quantify VGM parameters and their uncertainties using the MCMC inversion strategy. The findings indicate that the stochastic inversion of time-lapse GPR data does indeed allow for a substantial refinement in the inferred posterior VGM parameter distributions. In turn, this significantly improves knowledge of the hydraulic properties, which are required to predict hydraulic behaviour. Finally, another aspect that needed to be addressed involved the comparison of time-lapse GPR data collected under different infiltration conditions (i.e., natural loading and forced infiltration conditions) to estimate the VGM parameters using the MCMC inversion strategy. The results show that for the synthetic example, considering data collected during a forced infiltration test helps to better refine soil hydraulic properties compared to data collected under natural infiltration conditions. When investigating data collected at the Arrenaes field site, further complications arised due to model error and showed the importance of also including a rigorous analysis of the propagation of model error with time and depth when considering time-lapse data. Although the efforts in this thesis were focused on GPR data, the corresponding findings are likely to have general applicability to other types of geophysical data and field environments. Moreover, the obtained results allow to have confidence for future developments in integration of geophysical data with stochastic inversions to improve the characterization of the unsaturated zone but also reveal important issues linked with stochastic inversions, namely model errors, that should definitely be addressed in future research.