Using 137 Cs as a tool for the assessment and the management of erosion/sedimentation risks in view of the restoration of the Rainbow Smelt (Osmerus mordax) fish population in the Boyer River basin (Québec, Canada)

The Boyer River (Québec, Canada) drains a 217 km 2 watershed that is under cultivation at 60%. The last 2 km of the river bed has always been used as a spawning ground by Rainbow Smelts (Osmerus mordax). This fish population, which plays an important ecological role in the St.Lawrence River estuary, has dramatically declined over the last decades. Siltation and excessive algal growth in the spawning area were identified as the most probable causes of the fish population decline; suggesting that soil erosion, nutrient and sediment transport are major factors underlying the environmental problem . In this context, 137Cs provides an effective tool for investigating the magnitude and spatial distribution of long-term soil redistribution taking place in the watershed. Sampling of cultivated fields, riverbanks, bottom sediments and forested sites were thus undertaken to help understand the erosive behaviour of the watershed. Results obtained so far suggest in-field erosion rates of up to 13 t ha-1 yr-1 with net outputs reaching 11 t ha-1 yr-1. These results agree well with estimates obtained from the USLE. The 137Cs data indicate that fields located in the upstream half of the basin produce smaller sediment loadings than those in the downstream portion, despite higher soil erodibilities and more frequent ose for annual crops. They also suggest that more than 75% of the sediment deposited in the spawning area originates from cultivated fields, and less than 25% from streambanks

Ferromagnetism and magnetodielectric effect in insulating LaBiMn4∕3Co2∕3O6 thin films

International audienceHigh quality epitaxial thin films of LaBiMn4∕3Co2∕3O6 perovskite were fabricated on (001)-oriented SrTiO3 and LaAlO3 substrates by the pulsed laser deposition technique. Magnetization measurements reveal a strong magnetic anisotropy and a ferromagnetic behavior that is in agreement with a superexchange interaction between Mn4+ and Co2+ ions, which are randomly distributed in the B site. A distinct anomaly is observed in the dielectric measurements at 130Kcorresponding to the onset of the magnetic ordering, suggesting a coupling. Above this temperature, the extrinsic Maxwell–Wagner effect is dominating. These results are explained using the Raman spectroscopic studies indicating a weak spin-lattice interaction around this magnetic transition.A.K.K. thanks the French Ministry of Education and Research for a fellowship award. This work was carried out in the frame of the NoE FAME (FP6-5001159-1), the STREP MaCoMuFi (NMP3-CT-2006-033221), and the STREP CoMePhS (NMP4-CT-2005-517039) supported by the European Community and by the CNRS, France. Partial support from the ANR (NT05-1-45177 and NT05-3-41793) is also acknowledged. The authors would also like to acknowledge Dr. L. Mechin and Mr. C. Fur for their help in the experiments and W.C. Sheets, M. Maglione, and J.F. Scott for careful reading of the manuscript

Genetic risk factors for VIPN in childhood acute lymphoblastic leukemia patients identified using whole-exome sequencing.

To identify genetic markers associated with vincristine-induced peripheral neuropathy (VIPN) in childhood acute lymphoblastic leukemia. Whole-exome sequencing data were combined with exome-wide association study to identify predicted-functional germline variants associated with high-grade VIPN. Genotyping was then performed for top-ranked signals (n = 237), followed by validation in independent replication group (n = 405). Minor alleles of rs2781377/SYNE2 (p = 0.01) and rs10513762/MRPL47 (p = 0.01) showed increased risk, whereas that of rs3803357/BAHD1 had a protective effect (p = 0.007). Using a genetic model based on weighted genetic risk scores, an additive effect of combining these loci was observed (p = 0.003). The addition of rs1135989/ACTG1 further enhanced model performance (p = 0.0001). Variants in SYNE2, MRPL47 and BAHD1 genes are putative new risk factors for VIPN in childhood acute lymphoblastic leukemia