Pour une notion philosophiquement acceptable de loi en théorie de la connaissance

La notion de loi semble pleine de métaphysique implicite et même d’idéologie… mais elle peut être réinterprétée a minima en philosophie (critique) des sciences. Il faut pour cela écarter la dimension de nécessité et concevoir la loi comme énoncé d’universalité, elle-même relative, ou plus exactement : pragmatique. Les critères sémantiques de cette universalité, à l’analyse, ne constituent pas un engagement ontologique au sens de Quine, d’où notamment une mise à l’écart de la notion de « lois de la nature ». La loi peut être mieux comprise comme un énoncé d’engagement pragmatique, dans lequel fait relief une propriété sémantique : la descriptivité.Although metaphysics and, to a certain extent, ideology are implicit within the concept of law, a (critical) philosophy of science can render a minimal interpretation of it. By restraining the notion of necessity, law can be conceived as a statement of universality, which itself is relative, or rather pragmatic. In addition, a thorough analysis shows that the semantic criteria for this universality need not imply an ontological commitment in Quine’s meaning of the term, which avoids having to make room for ideas like “laws of nature”. Law can be better understood as a statement of pragmatic commitment, with an outstanding semantic property: descriptivity

« Les catastrophes lentes »

Les « catastrophes futures » trop visibles masquent les catastrophes lentes du présent, et parfois, ou peut-être souvent, elles les alimentent. Cette situation semble convenir à tout le monde : les pouvoirs qui en profitent pour réclamer plus de pouvoir, afin de nous protéger contre les catastrophes futures, et les acteurs de base qui en profitent pour déléguer plus encore, tant ces menaces les dépassent, c’est-à-dire qui en profitent pour ne rien faire.All too visible future disasters dissimulate actual slow disasters and sometimes, or maybe usually, even fuel them. This situation seems to be convenient for everyone : powers take the opportunity to demand more power to protect us from future disasters, and individual agents take the opportunity to delegate more and more, in face of such overwhelming menaces, which means they take the opportunity to do nothing.Die zu klaren Katastrophen « der Zukunft » maskieren die langsamen, die schleichenden Katastrophen der Gegenwart, und manchmal, oder vielleicht sogar oft, bringen sie ihnen neue Nahrung. Diese Situation scheint allen zu behagen : den Machthabern, die davon profitieren um mehr Macht zu verlangen, um uns vor den Katastrophen der Zukunft zu beschützen, und die Menschen der Basis, die noch mehr delegieren, die also davon profitieren um passiv zu bleiben, da sie demgegenüber nicht gewachsen sind

FALCON: a concept to extend adaptive optics corrections to cosmological fields

FALCON is an original concept for a next generation spectrograph at ESO VLT or at future ELTs. It is a spectrograph including multiple small integral field units (IFUs) which can be deployed within a large field of view such as that of VLT/GIRAFFE. In FALCON, each IFU features an adaptive optics correction using off-axis natural reference stars in order to combine, in the 0.8-1.8 \mu m wavelength range, spatial and spectral resolutions (0.1-0.15 arcsec and R=10000+/-5000). These conditions are ideally suited for distant galaxy studies, which should be done within fields of view larger than the galaxy clustering scales (4-9 Mpc), i.e. foV > 100 arcmin2. Instead of compensating the whole field, the adaptive correction will be performed locally on each IFU. This implies to use small miniaturized devices both for adaptive optics correction and wavefront sensing. Applications to high latitude fields imply to use atmospheric tomography because the stars required for wavefront sensing will be in most of the cases far outside the isoplanatic patch.Comment: To appear in the Backaskog "Second Workshop on ELT" SPIE proceeding

Tatouage d'images cryptées pour l'aide au télédiagnostic

Le développement d'interfaces de visualisation à distance pour des images médicales rencontre des problèmes de sécurité de données. Dans ce papier, nous présentons une combinaison des techniques de cryptage et de tatouage d'images. Nous proposons un système permettant de transférer des images médicales de manière sécurisée en générant une clef pour crypter l'image, puis en tatouant l'image avec la clef de cryptage et les données concernant le patient

Where the Harm Comes From: Ethics of Mediating Collectives

This article defines the intermediate level between personal agency and global issues of injustice as a complex system of mediating collectives, the agency of which must be addressed specifically in organizational and ontological but also in ethical and political terms. We target three domains of global injustice: economic, environmental, and gender-related, following the threads of briefly stated cases in these domains. Our conclusion suggests recommendations for dealing more realistically and more efficiently with global injustice that obstinately thrives from somewhere deep into the structures of the contemporary world. Our recommendations will bear on (a) individual responsibility in a collective, (b) virtuous direct and indirect action, (c) awareness of and communication with interdependent collectives, (d) optimal communication within every collective, (e) readiness for joint-action as an authentic group-agent

Oxidized low-density lipoprotein and ankle-brachial pressure index in patients with clinically evident peripheral arterial disease

OBJECTIVES: To investigate whether oxidized low-density lipoprotein is a suitable predictor of peripheral arterial disease severity. The role of oxidized low-density lipoprotein in the pathogenesis of atherosclerosis has already been investigated. Its relevance as a predictor of the appearance and worsening of coronary arterial disease is also well known. However, the same is not true regarding peripheral arterial disease. METHOD: Eighty-five consecutive patients with an ankle-brachial pressure index (ABPI) < 0.9 and the presence of either intermittent claudication or critical lower leg ischemia were included. The plasma level of IgG autoantibodies against oxidized low-density lipoprotein was evaluated through an enzyme-linked immunosorbent assay. The results were categorized into quartiles according to the ankle-brachial pressure index (a marker of peripheral arterial disease severity), and significant differences were investigated with the Kruskal-Wallis test. RESULTS: There was no significant difference between the quartiles for this population (p = 0.33). No correlation was found between the ankle-brachial pressure index and oxidized low-density lipoprotein levels in subjects with clinically evident peripheral arterial disease with a wide range of clinical manifestations. CONCLUSIONS: Oxidized low-density lipoprotein is not a good predictor of peripheral arterial disease severity

Effect of the type of oak barrels employed during ageing on the ellagitannin profile of wines

[EN] Background and Aims: Ellagitannins released from wood to wine during barrel ageing can affect wine colour and astringency. This work aimed to examine the influence that oak wood type (French or American) and age (first-fill or second-fill) of barrels has on the concentration of individual ellagitannins and their evolution during winemaking and ageing. Methods and Results: The ellagitannin composition of red wines during ageing was determined by HPLC-MS/MS-multiple reaction monitoring. Differences in the extractability and stability of the individual ellagitannins were observed. Moreover, the ellagitannin composition of wines was determined by the type of barrel. Wines aged in new French oak barrels showed a concentration of ellagitannin about twofold higher than that aged in American or in second-fill French ones. The vescalagin/castalagin ratio was higher in wines aged in French oak barrels than that in wines aged in American barrels. Wine samples were grouped by discriminant analysis into three groups depending on the type of barrel employed during ageing. Conclusions: The ellagitannin profile of aged red wines is strongly influenced by the type of oak barrel employed.Wines aged in new French oak barrels can be differentiated from those aged in second-fill French or in new American oak barrels by the ellagitannin concentration, whereas the vescalagin/castalagin ratio may assist in tracing the oak type (French or American) of the barrels. Significance of the Study: The ellagitannin concentration along with the vescalagin/castalagin ratio in red wines aged in oak barrels can be employed for tracing the oak type of the barrels

Structure and rheological properties of model microemulsion networks filled with nanoparticles

Model microemulsion networks of oil droplets stabilized by non ionic surfactant and telechelic polymer C18-PEO(10k)-C18 have been studied for two droplet-to-polymer size ratios. The rheological properties of the networks have been measured as a function of network connectivity and can be described in terms of simple percolation laws. The network structure has been characterised by Small Angle Neutron Scattering. A Reverse Monte Carlo approach is used to demonstrate the interplay of attraction and repulsion induced by the copolymer. These model networks are then used as matrix for the incorporation of silica nanoparticles (R=10nm), individual dispersion being checked by scattering. A strong impact on the rheological properties is found for silica volume fractions up to 9%

Understanding the ellagitannin extraction process from oak wood

[EN] The extractability of the main oak ellagitannins has been studied in five model solutions containing different types of oak chips (two sizes and different toasting degrees for each size). A new extraction kinetic model has been proposed from the quantitative experimental results obtained by means of HPLCeESI-MS/MS-multiple reaction monitoring method. The model considers an initial extraction (i.e., washing step) followed by a diffusion step, which involves two different processes that follow first-order kinetics at different rates. Differences in the extractability of the ellagitannins in the different model solutions have been observed and explained on the basis of the kinetic model here proposed

KIT is required for hepatic function during mouse post-natal development

<p>Abstract</p> <p>Background</p> <p>The <it>Kit </it>gene encodes a receptor tyrosine kinase involved in various biological processes including melanogenesis, hematopoiesis and gametogenesis in mice and human. A large number of <it>Kit </it>mutants has been described so far showing the pleiotropic phenotypes associated with partial loss-of-function of the gene. Hypomorphic mutations can induce a light coat color phenotype while complete lack of KIT function interferes with embryogenesis. Interestingly several intermediate hypomorphic mutations induced in addition growth retardation and post-natal mortality.</p> <p>Results</p> <p>In this report we investigated the post-natal role of <it>Kit </it>by using a panel of chemically-induced hypomorphic mutations recently isolated in the mouse. We found that, in addition to the classical phenotypes, mutations of <it>Kit </it>induced juvenile steatosis, associated with the downregulation of the three genes, <it>VldlR</it>, <it>Lpin1 </it>and <it>Lpl</it>, controlling lipid metabolism in the post-natal liver. Hence, <it>Kit </it>loss-of-functions mimicked the inactivation of genes controlling the hepatic metabolism of triglycerides, the major source of energy from maternal milk, leading to growth and viability defects during neonatal development.</p> <p>Conclusion</p> <p>This is a first report involving KIT in the control of lipid metabolism in neonates and opening new perspectives for understanding juvenile steatosis. Moreover, it reinforces the role of Kit during development of the liver and underscores the caution that should be exerted in using KIT inhibitors during anti-cancer treatment.</p