La dispersion chez le chevreuil européen, Capreolus capreolus, dans un paysage hétérogène

TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF

Navβ4 : un-suppresseur de métastases et un nouveau biomarqueur des cancers agressifs

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Multi-spot Laser Fault Injection Setup: New Possibilities for Fault Injection Attacks

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Multi-spot Laser Fault Injection Setup: New Possibilities for Fault Injection Attacks

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Contrasted effects of fertilization and understory removal on pine trees growth and soil functioning in southwestern French moorlands

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Développement d’une méthode d’identification des champignons mycorhiziens à arbuscules par spectrométrie de masse. (MALDI- TOF-MS)

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New method for the identification of arbuscular mycorrhizal fungi by proteomic-based biotyping of spores using MALDI-TOF-MS

Abstract Arbuscular mycorrhizal fungi (AMF, Glomeromycota) are mutualistic symbionts associated with majority of land plants. These fungi play an important role in plant growth, but their taxonomic identification remains a challenge for academic research, culture collections and inoculum producers who need to certify their products. Identification of these fungi was traditionally performed based on their spore morphology. DNA sequence data have successfully been used to study the evolutionary relationships of AMF, develop molecular identification tools and assess their diversity in the environment. However, these methods require considerable expertise and are not well-adapted for “routine” quality control of culture collections and inoculum production. Here, we show that Matrix-Assisted Laser Desorption Ionisation Time of Flight Mass Spectrometry proteomic-based biotyping is a highly efficient approach for AMF identification. Nineteen isolates belonging to fourteen species, seven genera and five families were clearly differentiated by MALDI biotyping at the species level, and intraspecific differentiation was achieved for the majority. AMF identification by MALDI biotyping could be highly useful, not only for research but also in agricultural and environmental applications. Fast, accurate and inexpensive molecular mass determination and the possibility of automation make MALDI-TOF-MS a real alternative to conventional morphological and molecular methods for AMF identification

Ion exchanges K+ = Na+ and availability of two groups of exchange sites in a vermiculite. I. Providing evidence for two site groups

If mixed aqueous solutions of K+ and Na+ ions are allowed to percolate through flakes of K-and Na-vermiculites, 1 to 2 mm in size, at 25, 60 and 90°C, one obtains water-swollen biionic vermiculites in equilibrium with the solutions. The cation exchange isotherms are complex and exhibit a hysteresis. Comparison of isotherms and X-ray diffraction data shows that cation-exchange involves whole and alternate interlayer spaces. The shape of the isotherms reveals the existence of two groups of cation exchange sites corresponding to the alternate interlayer spaces. These two site groups are responsible for two cation exchange reactions.Saehr Daniel, Le Dred Ronan, Baron Jacques. Ion exchanges K+ = Na+ and availability of two groups of exchange sites in a vermiculite. I. Providing evidence for two site groups. In: Proceedings of the 9th international Clay Conference, Strasbourg, 1989. Vol II : Surface chemistry. Structure and mixed layering of clays. Strasbourg : Institut de Géologie – Université Louis-Pasteur, 1990. pp. 155-163. (Sciences Géologiques. Mémoire, 86

Exploration as a key component of natal dispersal: dispersers explore more than philopatric individuals in roe deer

International audienceNatal dispersal (i.e. movements between the natal range of an individual and its first breeding site) is a complex process which can have profound impacts on population dynamics. In most species, only a proportion of juveniles actually disperse, but few empirical data are available on the factors that drive the decision to disperse. To understand the behavioural ontogeny of the decision to disperse, we investigated the ranging behaviour of 66 juvenile roe deer, Capreolus capreolus, monitored with GPS collars prior to and during the dispersal phase. We compared the number and features (distance and duration) of exploratory movements during the period prior to dispersal between philopatric individuals and dispersers. Overall, 76% of the juveniles that dispersed during their first spring performed exploratory movements prior to the dispersal period. Indeed, exploration prior to the dispersal phase was much more common among future dispersers than among future philopatric individuals, suggesting that dispersal of juveniles is facilitated to some degree by predispersal exploration forays. Furthermore, the direction of the dispersal event was correlated with the direction of previous exploration, although there was no relationship between exploration distance and subsequent dispersal distance. Thus, it appears that individuals that subsequently disperse first explore their environment, prior to definitively leaving their natal range, probably to obtain information on potential suitable adult ranges. Exploratory movements prior to dispersal can thus provide information that influences an individual's decision on whether or not to disperse and, if so, in which direction. (C) 2013 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved

Unusual cerebrotendinous xanthomatosis with fronto-temporal dementia phenotype

Cerebrotendinous xanthomatosis (CTX) is an autosomal recessive lipid storage disease caused by a deficiency of the mitochondrial enzyme 27-sterol hydroxylase (CYP27). We report a 53-year-old man, with an unusual phenotype of CTX. He had xanthomas since adolescence. He had no mental retardation and developed at 44 years a progressive neuropsychiatric phenotype, suggestive of fronto-temporal dementia according to clinical Neary criteria. Cataract and ataxia were absent. Cerebral MRI revealed diffuse hyperintense T2 abnormalities in the supratentorial white matter without cerebellar atrophy or lesions, while Technetium-99m-ECD brain SPECT revealed a severe cerebellar hypoperfusion. Serum cholestanol level was elevated with excessive urinary bile alcohols excretion. Mutation analysis revealed that he was compound heterozygous for two mutations in the CYP27A1 gene: 1016 C > T (exon 5) on one allele and a novel mutation, 1435C > G (exon 8) on the other allele. A follow-up study was conducted to evaluate the effects of chenodeoxycholic acid (CDCA) and simvastatin treatment during 3 years. In spite of this treatment, cognitive functions declined but no other signs of neurological deterioration appeared