75 research outputs found
Progress Report on Target Development
The present document is the D08 deliverable report of work package 1 (Target Development) from the MEGAPIE TEST project of the 5th European Framework Program. Deliverable D08 is the progress report on the activities performed within WP 1. The due date of this deliverable was the 5th month after the start of the EU project. This coincided with a technical status meeting of the MEGAPIE Initiative, that was held in March 2002 in Bologna (Italy). The content of the present document reflects the status of the MEGAPIE target development at that stage. It gives an overview of the Target Design, the related Design Support activities and the progress of the work done for the safety assessment and licensing of the target
Nociceptors: a phylogenetic view
The ability to react to environmental change is crucial for the survival of an organism and an essential prerequisite is the capacity to detect and respond to aversive stimuli. The importance of having an inbuilt “detect and protect” system is illustrated by the fact that most animals have dedicated sensory afferents which respond to noxious stimuli called nociceptors. Should injury occur there is often sensitization, whereby increased nociceptor sensitivity and/or plasticity of nociceptor-related neural circuits acts as a protection mechanism for the afflicted body part. Studying nociception and nociceptors in different model organisms has demonstrated that there are similarities from invertebrates right through to humans. The development of technology to genetically manipulate organisms, especially mice, has led to an understanding of some of the key molecular players in nociceptor function. This review will focus on what is known about nociceptors throughout the Animalia kingdom and what similarities exist across phyla; especially at the molecular level of ion channels
A MSFD complementary approach for the assessment of pressures, knowledge and data gaps in Southern European Seas : the PERSEUS experience
PERSEUS project aims to identify the most relevant pressures exerted on the ecosystems of the Southern
European Seas (SES), highlighting knowledge and data gaps that endanger the achievement of SES Good
Environmental Status (GES) as mandated by the Marine Strategy Framework Directive (MSFD). A complementary
approach has been adopted, by a meta-analysis of existing literature on pressure/impact/knowledge
gaps summarized in tables related to the MSFD descriptors, discriminating open waters from coastal
areas. A comparative assessment of the Initial Assessments (IAs) for five SES countries has been also
independently performed. The comparison between meta-analysis results and IAs shows similarities
for coastal areas only. Major knowledge gaps have been detected for the biodiversity, marine food
web, marine litter and underwater noise descriptors. The meta-analysis also allowed the identification
of additional research themes targeting research topics that are requested to the achievement of GES.
2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license.peer-reviewe
Effective Electronic and Ionic Conductivities of Dense EV-Designed NMC-Based Positive Electrodes using Fourier Based Numerical Simulations on FIB/SEM Volumes
International audienceExperimental conductivity measurements, obtained on NMC 532 -based electrodes with markedly different porosities and made with percolating and non-percolating CB/PVdF phase, are compared with full-field numerical predictions. These ones are based on segmented nanotomography images and phase bulk properties and contain no tunable parameter. A good agreement between the calculated and measured transport properties is observed. 3D current density fields give insights on the microstructure impacts on the current density distribution. Ionic transport is dominated by low tortuosity micrometric channels. Results also highlight the presence of “dead areas” in porosity that are crossed by a very low ionic current showing that, at high rate, the effective porosity may reduce to the micrometric pore network. For electronic conductivity, the CB/PVdF mixture percolation threshold is evaluated at 6%–7% in volume. Even below this key value threshold, CB/PVdF aggregates significantly improve electronic conductivity by forming gateways between NMC clusters thus minimising the constriction resistances between them. The size of the representative volume element relative to electronic and ionic conductivities is also investigated
Encapsulation of contrast imaging agents by polypropyleneimine-based dendrimersâ€
International audiencePolypropyleneimines (PPIs) functionalized by glycerol-based entities are prepared and characterized by diffusion-ordered spectroscopy NMR. Showing low cytotoxicity against MRC5 fibroblasts, their encapsulation capacities of gadolinium complexes was evaluated. T1 measurements were performed to determine the relaxivity of the encapsulated gadopentetate dimeglumine (GdBOPTA) in dendrimers of fourth and fifth generation (GD-PPI-4 and GD-PPI-5). Comparison of the GdBOPTA relaxivity and the relaxivity of GdBOPTA-loaded dendrimers showed a slight increase of the gadolinium chelate relaxivit
Impact of gadolinium-based contrast agents on the growth of fish cells lines
International audienceThe present study was the first approach conducted under environmental concentrations of Gd-DOTA and Gd-DTPA-BMA to assess cellular impacts of these compounds. Gd-DOTA (Gadoteric acid) is one of the most stable contrast agent, currently used as Dotarem® formulation during Magnetic Resonance Imaging exams. The study was mainly performed on a Zebra Fish cell line (ZF4; ATCC CRL-2050). At the concentrations of 0.127 nM and 63.59 nM (respectively 20 ng and 10 μg of Gd/L), we did not observed any toxicity of Dotarem® but a slowdown of the cell growth was clearly measured. The effect is independent of medium renewing during 6 days of cell culturing. The same effect was observed i-with Gd-DOTA on another fish cell line (RT W1 gills; ATCC CRL-2523) and ii-with another contrast agent (Gd-DTPA-BMA - Omniscan®) on ZF4 cells. On the ZF4 cell line, the diminution of the cell growth was of the same order during 20 days of exposure to a culture medium spiked with 63.59 nM of Dotarem® and was reversible within the following 8 days when Dotarem® was removed from the medium. As shown by using modified DOTA structure (Zn-DOTA), the effect may be due to the chelating structure of the contrast agent rather than to the Gd ion. Until now, the main attention concerning the impact of Gd-CA on living cells concerned the hazard due to Gd release. According to our results, quantifying the presence of Gd-CA chelating structures in aquatic environments must be also monitored
Influences of Bioavailability, Trophic Position, and Growth on Methylmercury in Hakes (Merluccius merluccius) from Northwestern Mediterranean and Northeastern Atlantic
Methylmercury (MeHg) determinations in hake, its food-chain, and the surrounding waters and sediments allowed us to show that the higher length or age normalized mercury concentrations of Northwestern Mediterranean (Gulf of Lions: GoL) muscle hakes compared to its Northeastern Atlantic (Bay of Biscay: BoB) counterpart are due to both biotic and abiotic differences between their ecosystems. Bioenergetic modeling reveals that the slower growth rate of Mediterranean hake favors the MeHg bioaccumulation in the fish muscle and explains most of the difference between GOL and BoB hake populations. In addition, the waters of the Mediterranean hake habitat favor a higher MeHg exposition, due to the upper position of the thermohalocline, where MeHg is formed. Furthermore, we show that, within the Mediterranean hake population, a major increase in the biomagnification power (the slope of the relationships between logMeHg and δ15N), from 0.36 up to 1.12, occurs when individuals enter adulthood, resulting from the combined effects of lowering growth rate and change in feeding habits. Finally, δ15N normalized Hg concentrations indicate that the highest Hg concentrations are for hake from the shelf edge and the lowest are for hake from the Rhône prodelta area, suggesting a lower Hg bioavailability in inshore environments, consistent with MeHg distributions in water, sediment, and preys. © 2012 American Chemical Society.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
- …