Piezoelectric signal suppression by a composite-pulse sequence in NMR

International audienceNumerous NMR techniques are available for the study of nuclei with spin I ≥ 1. These nuclei interact with their surrounding electric field gradient, which depends on the symmetry of the crystallographic site. Spurious (or piezoelectric) signals, due to the piezoelectric and ferroelectric properties of a LiNbO3 crystal and generated by the vibration of the macroscopic electric dipole of the crystal, have been observed with the one-pulse sequence and cancelled using a composite-pulse sequence. The suppression of these piezoelectric signals by this sequence is illustrated by lithium-7 (I = 3/2) nuclei. Java applets available in our web site www.pascal-man.com for the determination of quadrupole parameters from one-dimensional nutation method are also presented

Study of the serotonin transporter (SLC6A4) and BDNF genes in French patients with non syndromic mental deficiency

<p>Abstract</p> <p>Background</p> <p>Mental deficiency has been linked to abnormalities in cortical neuronal network connectivity and plasticity. These mechanisms are in part under the control of two interacting signalling pathways, the serotonergic and the brain-derived neurotrophic (BDNF) pathways. The aim of the current paper is to determine whether particular alleles or genotypes of two crucial genes of these systems, the serotonin transporter gene (<it>SLC6A4</it>) and the brain-derived neurotrophic factor gene (<it>BDNF</it>), are associated with mental deficiency (MD).</p> <p>Methods</p> <p>We analyzed four functional polymorphisms (rs25531, 5-HTTLPR, VNTR, rs3813034) of the <it>SLC6A4 </it>gene and one functional polymorphism (Val66 Met) of the <it>BDNF </it>gene in 98 patients with non-syndromic mental deficiency (NS-MD) and in an ethnically matched control population of 251 individuals.</p> <p>Results</p> <p>We found no significant differences in allele and genotype frequencies in the five polymorphisms studied in the <it>SLC6A4 </it>and <it>BDNF </it>genes of NS-MD patients versus control patients. While the comparison of the patterns of linkage disequilibrium (D') in the control and NS-MD populations revealed a degree of variability it did not, however, reach significance. No significant differences in frequencies of haplotypes and genotypes for VNTR/rs3813034 and rs25531/5-HTTLPR were observed.</p> <p>Conclusion</p> <p>Altogether, results from the present study do not support a role for any of the five functional polymorphisms of <it>SLC6A4 </it>and <it>BDNF </it>genes in the aetiology of NS-RM. Moreover, they suggest no epistatic interaction in NS-MD between polymorphisms in <it>BDNF </it>and <it>SLC6A4</it>. However, we suggest that further studies on these two pathways in NS-MD remain necessary.</p

QCompere @ REPERE 2013

International audienceWe describe QCompere consortium submissions to the REPERE 2013 evaluation campaign. The REPERE challenge aims at gathering four communities (face recognition, speaker identification, optical character recognition and named entity detection) towards the same goal: multimodal person recognition in TV broadcast. First, four mono-modal components are introduced (one for each foregoing community) constituting the elementary building blocks of our various submissions. Then, depending on the target modality (speaker or face recognition) and on the task (supervised or unsupervised recognition), four different fusion techniques are introduced: they can be summarized as propagation-, classifier-, rule- or graph-based approaches. Finally, their performance is evaluated on REPERE 2013 test set and their advantages and limitations are discussed

QCompere @ REPERE 2013

International audienceWe describe QCompere consortium submissions to the REPERE 2013 evaluation campaign. The REPERE challenge aims at gathering four communities (face recognition, speaker identification, optical character recognition and named entity detection) towards the same goal: multimodal person recognition in TV broadcast. First, four mono-modal components are introduced (one for each foregoing community) constituting the elementary building blocks of our various submissions. Then, depending on the target modality (speaker or face recognition) and on the task (supervised or unsupervised recognition), four different fusion techniques are introduced: they can be summarized as propagation-, classifier-, rule- or graph-based approaches. Finally, their performance is evaluated on REPERE 2013 test set and their advantages and limitations are discussed

6. « Être rock, ça veut pas dire être marginal »

Mignon Patrick, Klein Jean-Claude. 6. « Être rock, ça veut pas dire être marginal ». In: Vibrations, N. 3, 1986. Les musiques des radios. pp. 193-206

Les tests de mémoire longue appartiennent-ils au "camp du démon" ?

The purpose of this paper is to test the dependence structure of financial series of stock returns and foreign exchange rates. To do this, R/S analysis and various ARFIMA methods have been implemented in order to detect the presence of long-term memory. The main result concerns Canadian markets for which we find persistence and anti-persistence phenomena in the foreign exchange market (dollar-Canadian dollar) and in the stock market (TSE 300) respectively.L'objet de cet article est de tester le type de la structure de dépendance des séries financières d'indices boursiers et de taux de change. A cette fin ont été mises en œuvre les procédures de détection de la mémoire longue que sont les analyses R/S et les diverses techniques ARFIMA. Le résultat particulièrement intéressant concerne les marchés canadiens pour lesquels nous décelons des phénomènes de persistance sur le marché des changes ($/$ canadien) et d'anti-persistance sur le marché boursier (TSE 300).Lardic Sandrine, Mignon Valérie, Jessua Claude. Les tests de mémoire longue appartiennent-ils au "camp du démon" ? . In: Revue économique, volume 47, n°3, 1996. pp. 531-540

CO₂ monitoring in the South-West Indian Ocean over the last three decades

International audienc