Forest governance and REDD+ in Central Africa: towards a participatory model to increase stakeholder involvement in carbon markets

Forests play a significant role in the global carbon budget, and can help to mitigate climate change impacts. Tropical forests which experience high rates of deforestation and forest degradation are particularly important, as they are the most active in winter. Based on academic research into global environmental policies in Central Africa, this study finds that REDD+ policies can succeed when there is a carbon market mechanism that increases participation by developing countries, with better integration of forest management and community forestry. Incentives should be based on an appropriate baseline, accurate carbon stocks and fluxes estimation, a suitable silvicultural system and regular monitoring.     

Failure analysis case study on a Cu/low-k technology in package: New front-side approach using laser and plasma de-processing

Because of its advantages (reduction of thickness, improvement of the signal delay and of the thermal dissipation…), Cu/low-k technologies are more and more used for RF applications in semiconductor industry. The failure analysis of such devices becomes a new challenge. This paper deals with a failure analysis case study on copper and low-k dielectric structure encapsulated in a plastic package. It shows the limitations of the techniques used in a standard failure analysis flow and presents a new sample preparation combining laser package ablation and specific RIE process for front-side decapsulation. This innovative sample preparation flow has been found mandatory for solving the failure analysis case: it was demonstrated that there was not any defect at the surface of the die and this method enabled the access to an EOS defect located between two metal layers.     

Probing photonic and optoelectronic structures by apertureless scanning near-field optical microscopy

This report presents the Apertureless Scanning Optical Near-Field Microscope as a powerful tool for the characterization of modern optoelectronic and photonic components with sub-wavelength resolution. We present an overview of the results we obtained in our laboratory over the past few years. By significant examples, it is shown that this specific probe microscopy allows for in situ local quantitative study of semiconductor lasers in operation, integrated optical waveguides produced by ion exchange (single channel or Y junction), and photonic structures.     

Catheter infection in intensive care: influence of systematic replacement of central venous catheters on a guide wire every 4 days

OBJECTIVES: Determine whether systematic replacement of central venous catheters on a guide wire every 4 days leads to a lower rate of catheter infection. METHODS: We conducted a prospective randomized study comparing systematic catheter replacement with the standard procedure where one-way catheters are left in situ as needed. RESULTS: The study included 150 patients and 170 catheters. Catheter replacement on a guide wire was performed 169 times. The rate of infection was not significantly different between the group of patients with replacement (3.7 for 1000 catheter days) and the group with systematic replacement (5.4 for 1000 catheter days). No mechanical complications occurred during the replacement procedures on guide wires. CONCLUSION: We do not recommend systematically replacing catheters on a guide wire for the prevention of catheter infection. This procedure may however be indicated in case of suspected catheter infection as no mechanical of infectious complications occurred.     

Interaction between a coke and a tar. 2. Limit of tar penetration in coke porosity

The limit of penetration of a given coal-tar pitch into two cokes during mixing of the coke and liquid tar has been studied. It was shown that tar penetration is limited by compression of gas occluded in pores. Mercury porosimetry of cokes and pyrolysed coke-tar mixtures as well as micrographs of cokes impregnated with tar allow one to estimate the limiting pore diameter of tar penetration into coke at ca. 6 μm for the system considered.     

A Herbivore Tag-and-Trace System Reveals Contact- and Density-Dependent Repellence of a Root Toxin

Foraging behavior of root feeding organisms strongly affects plant-environment-interactions and ecosystem processes. However, the impact of plant chemistry on root herbivore movement in the soil is poorly understood. Here, we apply a simple technique to trace the movement of soil-dwelling insects in their habitats without disturbing or restricting their interactions with host plants. We tagged the root feeding larvae of Melolontha melolontha with a copper ring and repeatedly located their position in relation to their preferred host plant, Taraxacum officinale, using a commercial metal detector. This method was validated and used to study the influence of the sesquiterpene lactone taraxinic acid β-D-glucopyranosyl ester (TA-G) on the foraging of M. melolontha. TA-G is stored in the latex of T. officinale and protects the roots from herbivory. Using behavioral arenas with TA-G deficient and control plants, we tested the impact of physical root access and plant distance on the effect of TA-G on M. melolontha. The larvae preferred TA-G deficient plants to control plants, but only when physical root contact was possible and the plants were separated by 5 cm. Melolontha melolontha showed no preference for TA-G deficient plants when the plants were grown 15 cm apart, which may indicate a trade-off between the cost of movement and the benefit of consuming less toxic food. We demonstrate that M. melolontha integrates host plant quality and distance into its foraging patterns and suggest that plant chemistry affects root herbivore behavior in a plant-density dependent manner.     

Compound Node–Kayles on paths

In his celebrated book [J.H. Conway, On Numbers and Games, Academic Press, New-York, 1976, Second edition (2001), A.K. Peters, Wellesley, MA], J.H. Conway introduced twelve versions of compound games. We analyze these twelve versions for the Node–Kayles game on paths. For usual disjunctive compound, Node–Kayles has been solved for a long time under normal play, while it is still unsolved under misère play. We thus focus on the ten remaining versions, leaving only one of them unsolved.     

Gold metallizations for eutectic bonding of silicon wafers

Gold eutectic bonding of silicon wafers is a good candidate for wafer level vacuum packaging of vibrating MEMS: in this paper we investigated several e-beam evaporated metallizations stacks including a titanium adhesion layer, an optional diffusion barrier (Ni or Pt) and a gold film for eutectic bonding on Si and SiO₂/Si wafers. Interdiffusion in the multilayers for annealing temperatures (380–430°C) larger than the Au–Si eutectic temperature (363°C) and times corresponding to a bonding process was characterized by RBS, roughness and resistivity measurements. Au/Pt/Ti and Au/Ti/SiO₂ were found to have the best characteristics for bonding. This was confirmed by bonding experiments.