The contribution of 211 particles to the mechanical reinforcement mechanism of 123 superconducting single domains

in Superconductor Science and Technology (2004), 17(1), 169-174

Hardness and fracture toughness of Dy-123 single domains were studied by Vickers in micro-indentation. A significant anisotropy of the mechanical properties was observed. Hardness tests give higher values ... [more ▼]

Hardness and fracture toughness of Dy-123 single domains were studied by Vickers in micro-indentation. A significant anisotropy of the mechanical properties was observed. Hardness tests give higher values when performed in (001) planes rather than in planes parallel to the c-axis. Moreover, the cracks pattern around the indentation follows preferential orientation in planes parallel to the c-axis whereas a classical 'four-cracks' pattern is observed in the (001) planes. It has been possible to show the crucial role played by the 211 particles in the deviating mechanism of cracks and the relevance of the high homogeneity of 211-particle distribution in the material. [less ▲]

Contribution of a tyrosine-based motif to cellular trafficking of wild-type and truncated NPY Y(1) receptors.

in Cellular Signalling (2011), 23(1), 228-38

The human NPY Y(1) receptor undergoes fast agonist-induced internalization via clathrin-coated pits then recycles back to the cell membrane. In an attempt to identify the molecular determinants involved ... [more ▼]

The human NPY Y(1) receptor undergoes fast agonist-induced internalization via clathrin-coated pits then recycles back to the cell membrane. In an attempt to identify the molecular determinants involved in this process, we studied several C-terminal truncation mutants tagged with EFGP. In the absence of agonist, Y(1) receptors lacking the last 32 C-terminal amino acids (Y(1)Delta32) are constitutively internalized, unlike full-length Y(1) receptors. At steady state, internalized Y(1)Delta32 receptors co-localize with transferrin, a marker of early and recycling endosomes. Inhibition of constitutive internalization of Y(1)Delta32 receptors by hypertonic sucrose or by co-expression of Rab5aS34N, a dominant negative form of the small GTPase Rab5a or depletion of all three isoforms of Rab5 indicates the involvement of clathrin-coated pits. In contrast, a truncated receptor lacking the last 42 C-terminal amino acids (Y(1)Delta42) does not constitutively internalize, consistent with the possibility that there is a molecular determinant responsible for constitutive internalization located in the last 10 amino acids of Y(1)Delta32 receptors. We show that the agonist-independent internalization of Y(1)Delta32 receptors involves a tyrosine-based motif YXXPhi. The potential role of this motif in the behaviour of full-length Y(1) receptors has also been explored. Our results indicate that a C-terminal tyrosine-based motif is critical for the constitutive internalization of truncated Y(1)Delta32 receptors. We suggest that this motif is masked in full-length Y(1) receptors which do not constitutively internalize in the absence of agonist. [less ▲]

Contribution of atom transfer radical processes to the functionalization and grafting of poly-ε-caprolactone

Poster (2004, May 27)

Contribution of cobalt-mediated radical polymerization to macromolecular engineering and photodynamic therapy

Doctoral thesis (2011)

Cobalt-mediated radical polymerization (CMRP) is an emerging class of controlled radical polymerization technique based on the reversible deactivation of the propagating radicals by a cobalt complex. This ... [more ▼]

Cobalt-mediated radical polymerization (CMRP) is an emerging class of controlled radical polymerization technique based on the reversible deactivation of the propagating radicals by a cobalt complex. This thesis aims at broadening the nature, the structure, the properties and the end-use of (co)polymers accessible by CMRP. The first part of this work is devoted to the synthesis of novel statistical, graft and block copolymers by CMRP. First, the statistical copolymerization of conjugated (n-butyl acrylate) with a non-conjugated one (vinyl acetate) has been successfully controlled by bis(acetylacetonato)cobalt(II). The optimal experimental conditions were then implemented to the copolymerization of vinyl acetate with poly(ethylene glycol) acrylate, which yielded (quasi-)diblock amphiphilic graft copolymers for potential biomedical applications in one step. CMRP also revealed successful for the synthesis of well-defined thermo-responsive copolymers based on poly(N-vinylcaprolactam), either amphiphilic or double-hydrophilic at room temperature. In the second part of this thesis, we investigated the potential of CMRP for the synthesis of new agents for cancer photodynamic therapy. The synthesis of such photosensitizers relied on the chain-end functionalization by [60]fullerene of water-soluble (co)polymers (or precursors) prepared by CMRP. The photodynamic activity of poly(vinyl alcohol)/C60, poly(N-vinylpyrrolidone-co-vinyl acetate)/C60 and poly(PEG acrylate-co-vinyl acetate)/C60 nanohybrids were assessed through photophysical and in vitro experiments. Also, the ability of the nanohybrids to avoid recognition by the immune system was evaluated by a protein adsorption test. Finally, some hints on how to improve the synthesis of the nanohybrids - and therefore, their photodynamic activity - were provided by a mechanistic study of the grafting onto C60 of macroradicals released by cobalt end-capped polymers [less ▲]

Contribution of CT scan for lesions affecting the spine

Poster (2011, January 22)

Contribution of cyclodextrins in the development of different pharmaceutical formulations of a new matrix metalloproteinase inhibitor

in Journal of Inclusion Phenomena and Macrocyclic Chemistry (2007, April), 57(1-4), 303-308

Ro 28-2653 is a new synthetic inhibitor of matrix metalloproteinases. The ability of these enzymes to degrade various components of the extracellular matrix seems to play a major role in tumors ... [more ▼]

Ro 28-2653 is a new synthetic inhibitor of matrix metalloproteinases. The ability of these enzymes to degrade various components of the extracellular matrix seems to play a major role in tumors progression and is potentially effective against bronchial remodeling in asthma and BPCO. Ro 28-2653 is very poorly soluble in water. This low solubility estimated at about 0.56 mu g/ml in water at 25 degrees C gives rise to difficulties in pharmaceutical formulation of oral, injectable or nebulizable solutions. The purpose of our study is to prepare and to characterize inclusion complexes between Ro 28-2653 and cyclodextrins and to investigate the biopharmaceutical repercussion of the inclusion of the active substance. The complex formation was investigated by phase solubility studies. H-1-NMR spectroscopy and molecular modeling studies were carried out to elucidate the structure of the inclusion complex between Ro 28-2653 and cyclodextrin. Oral, intravenous and nebulizable solutions of Ro 28-2653 were developed with cyclodextrin. The in vivo studies were performed on healthy sheep for the pharmacokinetic evaluation of the oral and intravenous formulations while the nebulization of the complex solution was studied by using an asthma model in mouse. [less ▲]

Contribution of dendrochronology to the study of droughts in northwestern France (late XIX-XXth century)

in Geophysical Research Abstracts (2007)

Contribution of eotaxin-1 to eosinophil chemotactic activity of moderate and severe asthmatic sputum

in American Journal of Respiratory & Critical Care Medicine (2004), 169(10), 1110-1117

The CC chemokine eotaxin-1 (CCL11) is chemotactic for eosinophils, basophils, and type 2 helper T cells and may play a role in allergic inflammation. We investigated its contribution as an eosinophil ... [more ▼]

The CC chemokine eotaxin-1 (CCL11) is chemotactic for eosinophils, basophils, and type 2 helper T cells and may play a role in allergic inflammation. We investigated its contribution as an eosinophil chemoattractant in asthmatic airway secretions (sampled as induced sputum), which possess chemotactic activity for eosinophils and T cells. Sputum samples collected from healthy subjects and subjects with mild, stable-moderate, unstable-moderate, and severe asthma were processed with phosphate-buffered saline and assayed for eotaxin by ELISA and for eosinophil chemotactic activity by fluorescence-based chemotaxis assay. The contribution of eotaxin to chemotactic activity was studied by using a high-affinity neutralizing human anti-eotaxin antibody, CAT-213. Sputum eotaxin concentration was significantly raised in moderate and severe asthma (p < 0.05 versus healthy control subjects) but not in mild asthma. Chemotactic activity was significantly increased in all asthmatic groups relative to healthy subjects (p < 0.05) and was significantly inhibited by CAT-213 (1100 nM) in subjects with moderate and severe asthma, with median inhibition of 52% (p < 0.05), 78% (p < 0.0001), and 86% (p < 0.0001), respectively, in samples representing stable-moderate, unstable-moderate, and severe asthma. Eotaxin contributed to the eosinophil chemotactic activity of sputum from subjects with more severe forms of asthma but not mild asthma, suggesting that its contribution is more important in more severe disease. This activity is inhibited significantly by CAT-213. [less ▲]

The contribution of ERS1 SAR data in neotectonics

in Guyenne, T. D. (Ed.) Proceedings of the Second ERS Applications Workshop, London, UK, 6-8 December 1995 (1996)

The contribution of familiarity to within- and between-domain associative recognition memory: Use of a modified remember/know procedure

in European Journal of Cognitive Psychology (2010), 22(6), 922-943

The purpose of the present study was to determine the extent to which familiarity can support associative recognition memory as a function of whether the associations are within- or between-domain ... [more ▼]

The purpose of the present study was to determine the extent to which familiarity can support associative recognition memory as a function of whether the associations are within- or between-domain. Standard recognition and familiarity only performance were compared in different participants, using a new adaptation of the remember/know procedure. The results indicated that within-domain (face face) associative recognition was mainly supported by familiarity. In contrast, familiarity provided relatively poor support to between-domain (face name) associative recognition for which optimal performance required a major recollection contribution. These findings suggest that familiarity can support associative recognition memory, particularly for within-domain associations, and contrast with the widely held view that associative recognition depends largely on recollection. [less ▲]