Le concept de personne éduquée : un holisme éducatif

Le but de l’article est d’exposer les différentes raisons qui interdisent d’identifier le fait d’être savant et celui d’être éduqué. Il montre que l’éducation, outre qu’elle porte également sur des inclinations, implique, entre autres choses, le développement d’une perspective cognitive distincte des savoirs et capacités spécialisées et conclut qu’une telle perspective, si elle peut être apprise ou découverte par le sujet, ne peut pas, stricto sensu, lui être enseignée

Recension de Michel Le Du

Introduction Construire une problématique est une chose, faire du concept même de problème l’objet d’une analyse philosophique suivie en est une autre. Les auteurs que commente M. Fabre ont, chacun à leur manière, constitué le problème en philosophème, et l’ouvrage que nous commentons suit cette même voie. On peut même dire qu’il livre, à différents moments, des éléments conduisant à une présentation synoptique de la notion. Cela se voit..

Electronic excited state of protonated aromatic molecules: protonated Fluorene

The photo-fragmentation spectrum of protonated fluorene has been recorded in the visible spectral region, largely red shifted as compared to the first excited state absorption of neutral fluorene. The spectrum shows two different vibrational progressions, separated by 0.19 eV that are assigned to the absorption of two isomers. As in protonated linear PAHs, comparison with ab-initio calculations indicates that the red shift is due to the charge transfer character of the excited state

Current results of the PERSEE testbench: the cophasing control and the polychromatic null rate

Stabilizing a nulling interferometer at a nanometric level is the key issue to obtain deep null depths. The PERSEE breadboard has been designed to study and optimize the operation of a cophased nulling bench in the most realistic disturbing environment of a space mission. This presentation focuses on the current results of the PERSEE bench. In terms of metrology, we cophased at 0.33 nm rms for the piston and 80 mas rms for the tip/tilt (0.14% of the Airy disk). A Linear Quadratic Gaussian (LQG) control coupled with an unsupervised vibration identification allows us to maintain that level of correction, even with characteristic vibrations of nulling interferometry space missions. These performances, with an accurate design and alignment of the bench, currently lead to a polychromatic unpolarised null depth of 8.9E-6 stabilized at 3E-7 on the [1.65-2.45] \mum spectral band (37% bandwidth).Comment: 17 pages, 10 figures, proceedings of the Optics+Photonics SPIE conference, San Diego, 201

Resolving diverse oxygen transport pathways across Sr-doped lanthanum ferrite and metal-perovskite heterostructures

Perovskite structured transition metal oxides are important technological materials for catalysis and solid oxide fuel cell applications. Their functionality often depends on oxygen diffusivity and mobility through complex oxide heterostructures, which can be significantly impacted by structural and chemical modifications, such as doping. Further, when utilized within electrochemical cells, interfacial reactions with other components (e.g. Ni- and Cr-based alloy electrodes and interconnects) can influence the perovskite's reactivity and ion transport, leading to complex dependencies that are difficult to control in real-world environments. Here we use isotopic tracers and atom probe tomography to directly visualize oxygen diffusion and transport pathways across perovskite and metal-perovskite heterostructures, i.e. (Ni-Cr coated) Sr-doped lanthanum ferrite (LSFO). Annealing in 18O2(g) results in elemental and isotopic redistributions through oxygen exchange (OE) in the LSFO while Ni-Cr undergoes oxidation via multiple mechanisms and transport pathways. Complementary density functional theory (DFT) calculations at experimental conditions provide rationale for OE reaction mechanisms and reveal a complex interplay of different thermodynamic and kinetic drivers. Our results shed light on the fundamental coupling of defects and oxygen transport in an important class of catalytic materials.Comment: 39 pages, 10 figure

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

Procalcitonin levels in acute exacerbation of COPD admitted in ICU: a prospective cohort study

<p>Abstract</p> <p>Background</p> <p>Antibiotics are recommended for severe acute exacerbation of chronic obstructive pulmonary disease (AECOPD) admitted to intensive care units (ICU). Serum procalcitonin (PCT) could be a useful tool for selecting patients with a lower probability of developing bacterial infection, but its measurement has not been investigated in this population.</p> <p>Methods</p> <p>We conducted a single center prospective cohort study in consecutive COPD patients admitted to the ICU for AECOPD between September 2005 and September 2006. Sputum samples or tracheal aspirates were tested for the presence of bacteria and viruses. PCT levels were measured at the time of admittance, six hours, and 24 hours using a sensitive immunoassay.</p> <p>Results</p> <p>Thirty nine AECOPD patients were included, 31 of which (79%) required a ventilator support at admission. The median [25%–75% interquartile range] PCT level, assessed in 35/39 patients, was: 0.096 μg/L [IQR, 0.065 to 0.178] at the time of admission, 0.113 μg/L [IQR, 0.074 to 0.548] at six hours, and 0.137 μg/L [IQR, 0.088 to 0.252] at 24 hours. The highest PCT (PCTmax) levels were less than 0.1 μg/L in 14/35 (40%) patients and more than 0.25 μg/L in 10/35 (29%) patients, suggesting low and high probability of bacterial infection, respectively. Five species of bacteria and nine species of viruses were detected in 12/39 (31%) patients. Among the four patients positive for <it>Pseudomonas aeruginosa</it>, one had a PCTmax less than 0.25 μg/L and three had a PCTmax less than 0.1 μg/L. The one patient positive for <it>Haemophilus influenzae </it>had a PCTmax more than 0.25 μg/L. The presence or absence of viruses did not influence PCT at time of admission (0.068 vs 0.098 μg/L respectively, <it>P </it>= 0.80).</p> <p>Conclusion</p> <p>The likelihood of bacterial infection is low among COPD patients admitted to ICU for AECOPD (40% with PCT < 0.1 μg/L) suggesting a possible inappropriate use of antibiotics. Further studies are necessary to assess the impact of a procalcitonin-based therapeutic strategy in critically ill COPD patients.</p

A clinical and EEG scoring system that predicts early cortical response (N20) to somatosensory evoked potentials and outcome after cardiac arrest

<p>Abstract</p> <p>Background</p> <p>Anoxic coma following cardiac arrest is a common problem with ethical, social, and legal consequences. Except for unfavorable somatosensory-evoked potentials (SSEP) results, predictors of unfavorable outcome with a 100% specificity and a high sensitivity are lacking. The aim of the current research was to construct a clinical and EEG scoring system that predicts early cortical response (N20) to somatosensory evoked potentials and 6-months outcome in comatose patients after cardiac arrest.</p> <p>Methods</p> <p>We retrospectively reviewed the records of all consecutive patients who suffered cardiac arrest outside our hospital and were subsequently admitted to our facility from November 2002 to July 2006. We scored each case based on early clinical and EEG factors associated with unfavorable SSEPs, and we assessed the ability of this score to predict SSEP results and outcome.</p> <p>Results</p> <p>Sixty-six patients qualified for inclusion in the cohort. Among them, 34 (52%) had unfavorable SSEP results. At day three, factors independently associated with unfavorable SSEPs were: absence of corneal (14 points) and pupillary (21 points) reflexes, myoclonus (25 points), extensor or absent motor response to painful stimulation (28 points), and malignant EEG (11 points). A score >40 points had a sensitivity of 85%, a specificity of 84%, and a positive predictive value (PPV) of 85% to predict unfavorable SSEP results. A score >88 points had a PPV of 100%, but a sensitivity of 18%. Overall, this score had an area under ROC curves of 0.919. In addition, at day three, a score > 69 points had a PPV of 100% with a sensitivity of 32% to predict death or vegetative state.</p> <p>Conclusion</p> <p>A scoring system based on a combination of clinical and EEG findings can predict the absence of early cortical response to SSEPs. In settings without access to SSEPs, this score may help decision-making in a subset of comatose survivors after a cardiac arrest.</p