30 research outputs found
Biomimetic apatite-based composite materials obtained by spark plasma sintering (SPS): physicochemical and mechanical characterizations
Nanocrystalline calcium phosphate apatites are biomimetic compounds analogous to bone mineral and are at the origin of the bioactivity of most biomaterials used as bone substitutes. Their unique surface reactivity originates
from the presence of a hydrated layer containing labile ions
(mostly divalent ones). So the setup of 3D biocompatible
apatite-based bioceramics exhibiting a high reactivity
requests the development of «low» temperature consolidation
processes such as spark plasma sintering (SPS), in order to preserve the characteristics of the hydrated nanocrystals. However, mechanical performances may still need to be improved for such nanocrystalline apatite bioceramics,
especially in view of load-bearing applications. The reinforcement by association with biopolymers represents
an appealing approach, while preserving the advantageous
biological properties of biomimetic apatites. Herein, we report the preparation of composites based on biomimetic apatite associated with various quantities of microcrystalline cellulose (MCC, 1â20 wt%), a natural
fibrous polymer. The SPS-consolidated composites were
analyzed from both physicochemical (X-ray diffraction,Fourier transform infrared, solid state NMR) and
mechanical (Brazilian test) viewpoints. The preservation of
the physicochemical characteristics of apatite and cellulose
in the final material was observed. Mechanical properties
of the composite materials were found to be directly related
to the polymer/apatite ratios and a maximum crushing
strength was reached for 10 wt% of MCC
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Comparison of choose-a-movie and approach-avoidance paradigms used to measure social motivation
Social motivation is a subjective state which is rather difficult to quantify. It has sometimes been conceptualised as âbehavioural effortâ to seek social contact. Two paradigms: approachâavoidance (AA) and choose a movie (CAM), based on the same conceptualisation, have been used to measure social motivation in people with and without autism. However, in absence of a direct comparison, it is hard to know which of these paradigms has higher sensitivity in estimating preference for social over non-social stimuli. Here we compare these two tasks for their utility in (1) evaluating social seeking in typical people and (2) identifying the influence of autistic traits on social motivation. Our results suggest that CAM reveals a clear preference for social stimuli over non-social in typical adults but AA fails to do so. Also, social seeking measured with CAM but not AA has a negative relationship between autistic traits
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Brief report: a comparison of the preference for viewing social and non-social movies in typical and autistic adolescents
The recently proposed Social Motivation theory (Chevallier et al., Trends in cognitive sciences 16(4):231â239, 2012) suggests that social difficulties in Autism Spectrum Condition (ASC) might be caused by a difference in the motivation to engage with other people. Here we compared adolescents with (Nâ=â31) and without (Nâ=â37) ASC on the Choose-a-Movie paradigm that measures the social seeking. The results showed a preference for viewing objects over smiling faces in ASC, which is in line with the theory of low social motivation. However, typical adolescents did not show any stimuli preferences, raising questions about developmental changes in social motivation. Age was found to play a significant role in moderating the choice behaviour of the participants. We discuss the implications of these findings in detail
Les fĂȘtes de Jeanne d'Arc Ă OrlĂ©ans et la Guerre froide
International audienceChaque annĂ©e, depuis presque six siĂšcles, OrlĂ©ans cĂ©lĂšbre sa dĂ©livrance du siĂšge anglais par l'armĂ©e de Jeanne d'Arc le 8 mai 1429. Le dĂ©roulement des fĂȘtes a plusieurs fois variĂ© mais elles n'ont Ă©tĂ© interdites ou rĂ©duites qu'en de rares occasions ; la derniĂšre, entre 1941 et 1944, quand les autoritĂ©s d'occupation ont imposĂ© qu'elles se limitent Ă un simple dĂ©pĂŽt de gerbe au pied de la statue de Foyatier place du Martroi. Depuis 1945, on cĂ©lĂšbre le mĂȘme jour la capitulation de l'Allemagne nazie, les cĂ©rĂ©monies Ă©tant dissociĂ©es mĂȘme si on ne manque pas de faire remarquer cette extraordinaire coĂŻncidence du calendrier. Les fĂȘtes sont devenues « religieuses, civiles et militaires » aprĂšs la PremiĂšre Guerre mondiale. En 1920, Jeanne d'Arc est successivement canonisĂ©e et la Chambre bleu horizon instaure la FĂȘte nationale de Jeanne d'Arc. Le 8 mai il y a deux temps forts : le matin une messe Ă la cathĂ©drale au cours de laquelle un invitĂ© ecclĂ©siastique prononce le panĂ©gyrique de la sainte, et l'aprĂšs-midi, un dĂ©filĂ© de cinq kilomĂštres dans les rues avec, dit-on, une moitiĂ© de la ville qui dĂ©file sous les regards de l'autre moitiĂ©. Ă partir de 1947 et l'entrĂ©e dans la Guerre froide, les communistes sont souvent fustigĂ©s comme diviseurs et mauvais Français. Et eux-mĂȘmes se mettent Ă l'Ă©cart
Les fĂȘtes de Jeanne dâArc Ă OrlĂ©ans et la Guerre froide
Chaque annĂ©e, depuis presque six siĂšcles, OrlĂ©ans cĂ©lĂšbre sa dĂ©livrance du siĂšge anglais par lâarmĂ©e de Jeanne dâArc le 8 mai 1429. Le dĂ©roulement des fĂȘtes a plusieurs fois variĂ© mais elles nâont Ă©tĂ© interdites ou rĂ©duites quâen de rares occasions ; la derniĂšre, entre 1941 et 1944, quand les autoritĂ©s dâoccupation ont imposĂ© quâelles se limitent Ă un simple dĂ©pĂŽt de gerbe au pied de la statue de Foyatier place du Martroi. Depuis 1945, on cĂ©lĂšbre le mĂȘme jour la capitulation de lâAllemagne na..
Terminologie médicale : langage médical courant et clés de son évolution
8e Ă©dition, ISBN 978222403057
JérÎme Fracastor. La syphilis ou le mal français/ Syphilis sive Morbus gallicus
Texte bilingue latin-français commentĂ©. Introduction sur les noms de la maladie. Annexes (notes de Scaliger, Lettres de Bembo)International audienceĂdition et traduction commentĂ©es du poĂšme de J. Fracasto
Bovine leukaemia virus-induced lymphocytosis in sheep is associated with reduction of spontaneous B cell apoptosis
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Temperatures and Enthalpies of SolidâSolid and Melting Transitions of the Odd-Numbered n- Alkanes C 21 , C 23 , C 25 , C 27 , and C 29
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