Geste instrumental et transmission musicale

Le geste instrumental recouvre un domaine extrêmement large puisque les différentes disciplines musicales – analyse auditive, histoire de l’interprétation et des idées musicales, esthétique, etc. – sont directement interpellées par cette expression. Après une incursion dans la polysémie du geste et une description de l’histoire des instruments de musique, un tableau synthétique des aspects fondamentaux du geste musical lié à l’instrument de musique permet d’esquisser des pistes de réflexion sur les pratiques musicales et leur enseignement

A silica long base tiltmeter with high stability and resolution

International audienceIn order to be able to provide valuable data in multiparameter measurement field operations, tiltmeters need to have a noise level better or equal than 10-9 rad for a period range from a few minutes to a few years and a long term stability ranging from 10-7 to 10-8 rad/yr. Tiltmeter measurements should also be as much as possible insensitive to thermal disturbances, by taking great care of the horizontality of the base line tube first. Secondly, thermal responses have been assessed. We also took great care of the coupling of our tiltmeters with the bedrock. We've designed a long base tiltmeter with sensors in silica which has a low dilatation coefficient. The linear variable displacement transducer is based on coil coupling (powered by an alternative voltage). Finally we show the results of two 100 m silica water tube tiltmeters which were installed in a mine in the French Vosges massif in the framework of a hydrology research project. These instruments show a remarkably good stability (6.5×10-9 rad/month) and a low noise level (of the order of 10-11 rad). Toroidal and spheroidal free modes of the Earth were observed after the two last major earthquakes on Sumatra

Light Hadron Weak Matrix Elements

I review this year's developments in the study of weak matrix elements of light hadrons on the lattice, with emphasis on K^0-\bar K^0 mixing and K -> pi pi decays.Comment: Lattice 2000 (Plenary), 17 pages (LaTeX), 6 postscript figures; plenary talk at 18th International Symposium on Lattice Field Theory (Lattice 2000), Bangalore, India, 17-22 Aug 200

Ruthenacycles and Iridacycles as Catalysts for Asymmetric Transfer Hydrogenation and Racemisation

Ruthenacycles, which are easily prepared in a single step by reaction between enantiopure aromatic amines and [Ru(arene)Cl2]2 in the presence of NaOH and KPF6, are very good asymmetric transfer hydrogenation catalysts. A range of aromatic ketones were reduced using isopropanol in good yields with ee’s up to 98%. Iridacycles, which are prepared in similar fashion from [IrCp*Cl2]2 are excellent catalysts for the racemisation of secondary alcohols and chlorohydrins at room temperature. This allowed the development of a new dynamic kinetic resolution of chlorohydrins to the enantiopure epoxides in up to 90% yield and 98% enantiomeric excess (ee) using a mutant of the enzyme Haloalcohol dehalogenase C and an iridacycle as racemisation catalyst.

Endothelial dysfunction and inflammation in asymptomatic proteinuria

Background. Proteinuria is associated with vascular risk and a systemic increase in vascular permeability. Endothelial dysfunction occurs early in atherosclerosis and modulates vascular permeability. Vascular risk and chronic inflammation are associated. This study investigates whether the increased vascular permeability in proteinuria reflects systemic endothelial dysfunction and chronic inflammation. Methods. Twenty-one patients with asymptomatic proteinuria (1.29 g/24 h; range 0.18 to 3.17) and 21 matched controls were studied. Microvascular endothelial function was assessed using acetylcholine iontophoresis. Maximum microvascular hyperemia (MMH) was assessed by flux response to local skin heating. Macrovascular endothelial function was assessed by flow- associated dilation (FAD) in the brachial artery using ultrasound. von Willebrand factor (vWF) was measured as a marker of endothelial activation. Low-grade inflammation was assessed by measurement of circulating C-reactive protein (CRP) values using a high sensitivity assay. Results. FAD was impaired in proteinuric subjects (AP) compared to controls [1.8 (0.2 to 5.3) AP vs. 3.8 (1.5 to 6.2) C %; P = 0.014]. There was no significant difference between groups in MMH or in the response to acetylcholine iontophoresis. The AP group had a higher CRP [4.0 (0.5 to 39.0) AP vs. 0.2 (0.1 to 21.3) C mg/L; P lt 0.001] and tendency to higher vWF [101.5 (67.0 to 197.0) AP vs. 77.5 (45.0 to 185.0) C IU/dL; P = 0.046] compared to controls. In the AP, but not control, group there was an inverse correlation between CRP and microvascular function as determined by acetylcholine iontophoresis (r = -0.509; P = 0.018). Conclusions. In AP subjects there is evidence of macrovascular endothelial dysfunction remote from the kidney and of low-grade inflammation that is associated with microvascular endothelial dysfunction

Hardy spaces of the conjugate Beltrami equation

We study Hardy spaces of solutions to the conjugate Beltrami equation with Lipschitz coefficient on Dini-smooth simply connected planar domains, in the range of exponents $1<\infty$. We analyse their boundary behaviour and certain density properties of their traces. We derive on the way an analog of the Fatou theorem for the Dirichlet and Neumann problems associated with the equation ${div}(\sigma\nabla u)=0$ with $L^p$-boundary data

NMDA receptor dysfunction contributes to impaired brain-derived neurotrophic factor-induced facilitation of hippocampal synaptic transmission in a Tau transgenic model.

While the spatiotemporal development of Tau pathology has been correlated with occurrence of cognitive deficits in Alzheimer's patients, mechanisms underlying these deficits remain unclear. Both brain-derived neurotrophic factor (BDNF) and its tyrosine kinase receptor TrkB play a critical role in hippocampus-dependent synaptic plasticity and memory. When applied on hippocampal slices, BDNF is able to enhance AMPA receptor-dependent hippocampal basal synaptic transmission through a mechanism involving TrkB and N-methyl-d-Aspartate receptors (NMDAR). Using THY-Tau22 transgenic mice, we demonstrated that hippocampal Tau pathology is associated with loss of synaptic enhancement normally induced by exogenous BDNF. This defective response was concomitant to significant memory impairments. We show here that loss of BDNF response was due to impaired NMDAR function. Indeed, we observed a significant reduction of NMDA-induced field excitatory postsynaptic potential depression in the hippocampus of Tau mice together with a reduced phosphorylation of NR2B at the Y1472, known to be critical for NMDAR function. Interestingly, we found that both NR2B and Src, one of the NR2B main kinases, interact with Tau and are mislocalized to the insoluble protein fraction rich in pathological Tau species. Defective response to BDNF was thus likely related to abnormal interaction of Src and NR2B with Tau in THY-Tau22 animals. These are the first data demonstrating a relationship between Tau pathology and synaptic effects of BDNF and supporting a contribution of defective BDNF response and impaired NMDAR function to the cognitive deficits associated with Tauopathies

Novel Insights into the Bovine Polled Phenotype and Horn Ontogenesis in Bovidae

Despite massive research efforts, the molecular etiology of bovine polledness and the developmental pathways involved in horn ontogenesis are still poorly understood. In a recent article, we provided evidence for the existence of at least two different alleles at the Polled locus and identified candidate mutations for each of them. None of these mutations was located in known coding or regulatory regions, thus adding to the complexity of understanding the molecular basis of polledness. We confirm previous results here and exhaustively identify the causative mutation for the Celtic allele (PC) and four candidate mutations for the Friesian allele (PF). We describe a previously unreported eyelash-and-eyelid phenotype associated with regular polledness, and present unique histological and gene expression data on bovine horn bud differentiation in fetuses affected by three different horn defect syndromes, as well as in wild-type controls. We propose the ectopic expression of a lincRNA in PC/p horn buds as a probable cause of horn bud agenesis. In addition, we provide evidence for an involvement of OLIG2, FOXL2 and RXFP2 in horn bud differentiation, and draw a first link between bovine, ovine and caprine Polled loci. Our results represent a first and important step in understanding the genetic pathways and key process involved in horn bud differentiation in Bovidae

Tetrastatin, the NC1 Domain of the α4(IV) Collagen Chain: A Novel Potent Anti-Tumor Matrikine

BACKGROUND: NC1 domains from α1, α2, α3 and α6(IV) collagen chains were shown to exert anti-tumor or anti-angiogenic activities, whereas the NC1 domain of the α4(IV) chain did not show such activities so far. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrate in the present paper that the NC1 α4(IV) domain exerts a potent anti-tumor activity both in vitro and in an experimental human melanoma model in vivo. The overexpression of NC1 α4(IV) in human UACC-903 melanoma cells strongly inhibited their in vitro proliferative (-38%) and invasive (-52%) properties. MT1-MMP activation was largely decreased and its cellular distribution was modified, resulting in a loss of expression at the migration front associated with a loss of migratory phenotype. In an in vivo xenograft model in athymic nude mice, the subcutaneous injection of NC1 α4(IV)-overexpressing melanoma cells induced significantly smaller tumors (-80% tumor volume) than the Mock cells, due to a strong inhibition of tumor growth. Exogenously added recombinant human NC1 α4(IV) reproduced the inhibitory effects of NC1 α4(IV) overexpression in UACC-903 cells but not in dermal fibroblasts. An anti-αvβ3 integrin blocking antibody inhibited cell adhesion on recombinant human NC1 α4(IV) substratum. The involvement of αvβ3 integrin in mediating NC1 α4(IV) effect was confirmed by surface plasmon resonance (SPR) binding assays showing that recombinant human NC1 α4(IV) binds to αvβ3 integrin (K(D) = 148 ± 9.54 nM). CONCLUSION/SIGNIFICANCE: Collectively, our results demonstrate that the NC1 α4(IV) domain, named tetrastatin, is a new endogenous anti-tumor matrikine

Phenomenology from lattice QCD

After a short presentation of lattice QCD and some of its current practical limitations, I review recent progress in applications to phenomenology. Emphasis is placed on heavy-quark masses and on hadronic weak matrix elements relevant for constraining the CKM unitarity triangle. The main numerical results are highlighted in boxes.Comment: 18 pages, 14 postscript figures. Plenary talk at ICHEP 2002, 24-31 July 2002, Amsterdam, The Netherland