Halogen molecular modifications at high pressure: the case of iodine.

Metallization and dissociation are key transformations in diatomic molecules at high densities particularly significant for modeling giant planets. Using X-ray absorption spectroscopy and atomistic modeling, we demonstrate that in halogens, the formation of a connected molecular structure takes place at pressures well below metallization. Here we show that the iodine diatomic molecule first elongates by ∼0.

Fate of cadmium in the rhizosphere of Arabidopsis halleri grown in a contaminated dredged sediment.

In regions impacted by mining and smelting activities, dredged sediments are often contaminated with metals. Phytotechnologies could be used for their management, but more knowledge on the speciation of metals in the sediment and on their fate after colonization by plant roots is needed. This work was focused on a dredged sediment from the Scarpe river (North of France), contaminated with Zn and Cd.

In situ chemical composition analysis of cirrhosis by combining synchrotron fourier transform infrared and synchrotron X-ray fluorescence microspectroscopies on the same tissue section.

Liver is subject to various chronic pathologies, progressively leading to cirrhosis, which is associated with an increased risk of hepatocellular carcinoma. There is an urgent need for diagnostic and prognostic markers of chronic liver diseases and liver cancer. Spectroscopy-based approaches can provide an overview of the chemical composition of a tissue sample offering the possibility of investigating in depth the subtle chemical changes associated with pathological states.

Comparative uptake and impact of TiO₂ nanoparticles in wheat and rapeseed.

Up to 2 million tons per year of titanium dioxide (TiO₂) nanoparticles (NP) are produced worldwide. This extensive production is postulated to result in release into the environment with subsequent contamination of soils and plants; however, few studies have examined TiO₂-NP uptake and impact on plants. In this study, wheat and rapeseed plantlets were exposed to 14 nm or 25 nm anatase TiO₂-NP in hydroponics conditions, either through root or leaf exposure.

Accumulation, translocation and impact of TiO2 nanoparticles in wheat (Triticum aestivum spp.): influence of diameter and crystal phase.

Intensive production of TiO(2) nanoparticles (TiO(2)-NPs) would lead to their release in the environment. Their ecotoxicological impact is still poorly documented, while their use in commercial goods is constantly increasing. In this study we compare root accumulation and root-to-shoot translocation in wheat of anatase and rutile TiO(2)-NPs with diameters ranging from 14 nm to 655 nm, prepared in water.

An X-ray micro-fluorescence study to investigate the distribution of Al, Si, P and Ca ions in the surrounding soft tissue after implantation of a calcium phosphate-mullite ceramic composite in a rabbit animal model.

Synthetic calcium phosphates, despite their bioactivity, are brittle. Calcium phosphate- mullite composites have been suggested as potential dental and bone replacement materials which exhibit increased toughness. Aluminium, present in mullite, has however been linked to bone demineralisation and neurotoxicity: it is therefore important to characterise the materials fully in order to understand their in vivo behaviour.

Cytotoxicity of CeO2 nanoparticles for Escherichia coli. Physico-chemical insight of the cytotoxicity mechanism.

The production of nanoparticles (NPs) is increasing rapidly for applications in electronics, chemistry, and biology. This interest is due to the very small size of NPs which provides them with many interesting properties such as rapid diffusion, high specific surface areas, reactivity in liquid or gas phase, and a size close to biomacromolecules. In turn, these extreme abilities might be a problem when considering a potentially uncontrolled exposure to the environment.