Dans le domaine de la pathologie psychotique, les rechutes représentent une problématique importante dans la trajectoire des sujets schizophrènes. À l’origine de nombreuses réhospitalisations, ces rechutes sont généralement liées à un défaut d’observance. Et lorsqu’on s’intéresse à cette dynamique, on s’aperçoit que la plupart des études qui se sont intéressées à l’observance médicamenteuse et aux comportements visant à améliorer celle-ci se sont avérées décevantes dans le domaine de la pathologie psychotique. Les progrès réalisés dans le traitement de la schizophrénie n’ont jusqu’ici pas modifié de manière radicale l’importance de l’adhésion des patients à leur médication, ni même la fréquence des rechutes. Si la rechute touche de 10 à 60 % des sujets schizophrènes selon les études, les taux de bonne observance médicamenteuse avoisinent 50 % pour l’ensemble des spécialités médicales et tombent parfois à moins de 20 % dans le domaine de la schizophrénie. Les raisons principales de cette problématique sont pour la plupart des auteurs liées à un manque d’efficacité de la molécule prescrite, à la survenue d’effets secondaires handicapants, à la présence de convictions personnelles désadaptées, voire à la pathologie elle-même. Dans un tel contexte, il semble intéressant de développer de nouvelles stratégies de prescription permettant de parvenir le plus rapidement possible à une dose minimale efficace, voire d’explorer d’autres options thérapeutiques. La revue de la littérature réalisée ici fait un point sur les études récemment publiées (2002–2008) mettant en exergue l’impact que la prescription d’un neuroleptique classique, d’un antipsychotique atypique per os ou d’un APAP peut avoir sur l’observance médicamenteuse et la fréquence des rechutes de patients souffrant de schizophrénie.

Pour le grand public, il existe une corrélation très forte entre actes violents (tels que meurtre, viol, inceste, et agressions) et figures du « fou » et du malade mental. La justice a besoin de l’expertise des psychiatres pour organiser scientifiquement la criminologie : connaissance de l’individu, individualisation de la peine et psychopathologisation des faits judiciaires venant agir comme caution scientifique à l’enfermement. L’évaluation de la dangerosité, déléguée actuellement dans notre pays au psychiatre, est en rupture avec les principes fondamentaux du droit pénal : la longueur de la peine n’est plus en rapport avec la culpabilité de l’auteur ou avec l’infraction qu’il a commise, mais dépend de sa dangerosité supposée, c’est-à-dire de sa probabilité à récidiver.

A well-known result in the area of dynamical systems asserts that any invertible hyperbolic operator on any Banach space is structurally stable. This result was originally obtained by Hartman in 1960 for operators on finite-dimensional spaces. The general case was independently obtained by Palis and Pugh around 1968. We will exhibit a class of examples of structurally stable operators that are not hyperbolic, thereby showing that the converse of the above-mentioned result is false in general. We will also prove that an invertible operator on a Banach space is hyperbolic if and only if it is expansive and has the shadowing property. Moreover, we will show that if a structurally stable operator is expansive, then it must be uniformly expansive. Finally, we will characterize the weighted shifts on the spaces $c_{0}(\mathbb{Z})$ and $\ell _{p}(\mathbb{Z})$ ($1\leq p<\infty$) that satisfy the shadowing property.

The characterization of biological and inorganic materials by determining their three-dimensional structure in conditions closer to their native state is a major challenge of technological research. Environmental scanning electron microscopy (ESEM) provides access to the observation of hydrated samples in water environments. Here, we present a specific device for ESEM in the scanning transmission electron microscopy mode, allowing the acquisition of tilt-series suitable for tomographic reconstructions. The resolution which can be obtained with this device is first determined. Then, we demonstrate the feasibility of tomography on wet materials. The example studied here is hydrophilic mesoporous silica (MCM-41). Finally, the minimum thickness of water which can be detected is calculated from Monte Carlo simulations and compared with the resolution expected in the tomograms.

Electron tomography is becoming one of the most used methods for structural analysis at nanometric scale in biological and materials sciences. Combined with chemical mapping, it provides qualitative and semiquantitative information on the distribution of chemical elements on a given sample. Due to the current difficulties in obtaining three-dimensional (3D) maps by energy-filtered transmission electron microscopy (EFTEM), the use of 3D chemical mapping has not been widely adopted by the electron microscopy community. The lack of specialized software further complicates the issue, especially in the case of data with a low signal-to-noise ratio (SNR). Moreover, data interpretation is rendered difficult by the absence of efficient segmentation tools. Thus, specialized software for the computation of 3D maps by EFTEM needs to include optimized methods for image series alignment, algorithms to improve SNR, different background subtraction models, and methods to facilitate map segmentation. Here we present a software package (EFTEM-TomoJ, which can be downloaded from http://u759.curie.fr/fr/download/softwares/EFTEM-TomoJ), specifically dedicated to computation of EFTEM 3D chemical maps including noise filtering by image reconstitution based on multivariate statistical analysis. We also present an algorithm named BgART (for background removing algebraic reconstruction technique) allowing the discrimination between background and signal and improving the reconstructed volume in an iterative way.

In a previous clinical study, a probiotic formulation (PF) consisting of Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 (PF) decreased stress-induced gastrointestinal discomfort. Emerging evidence of a role for gut microbiota on central nervous system functions therefore suggests that oral intake of probiotics may have beneficial consequences on mood and psychological distress. The aim of the present study was to investigate the anxiolytic-like activity of PF in rats, and its possible effects on anxiety, depression, stress and coping strategies in healthy human volunteers. In the preclinical study, rats were daily administered PF for 2 weeks and subsequently tested in the conditioned defensive burying test, a screening model for anti-anxiety agents. In the clinical trial, volunteers participated in a double-blind, placebo-controlled, randomised parallel group study with PF administered for 30 d and assessed with the Hopkins Symptom Checklist (HSCL-90), the Hospital Anxiety and Depression Scale (HADS), the Perceived Stress Scale, the Coping Checklist (CCL) and 24 h urinary free cortisol (UFC). Daily subchronic administration of PF significantly reduced anxiety-like behaviour in rats (P < 0·05) and alleviated psychological distress in volunteers, as measured particularly by the HSCL-90 scale (global severity index, P < 0·05; somatisation, P < 0·05; depression, P < 0·05; and anger–hostility, P < 0·05), the HADS (HADS global score, P < 0·05; and HADS-anxiety, P < 0·06), and by the CCL (problem solving, P < 0·05) and the UFC level (P < 0·05). L. helveticus R0052 and B. longum R0175 taken in combination display anxiolytic-like activity in rats and beneficial psychological effects in healthy human volunteers.

Ageing is associated with changes in physiology and morphology; nutritional strategies to decrease morbidity and to prolong life are of high interest. The aim of the study was to investigate the effects of lifelong supplementation with an oligofructose-enriched inulin on morphological and biological markers and lifespan in male and female rats. Male and female rats, age 3 months, were randomised into two groups to receive either a diet with 10 % of an oligofructose-enriched inulin (Synergy1) or a standard diet (control) for 27 months. The rats were weighed every 2 weeks and their food intake was evaluated on four successive days every 4–6 weeks. Samples were taken at 12, 18 and 24 months of age. During the whole intervention period, male rats receiving Synergy1 (SYN1-M) displayed lower body weight, cholesterol and plasma triacylglycerolaemia compared with the controls (Cont-M). The survival rate at 24 months of age of SYN1-M rats was 35·3 % greater than that of Cont-M rats. In female rats, the Synergy1 supplementation (SYN1-F) group also reduced body weight, cholesterol and triacylglycerolaemia levels, but results were less consistent over the experiment. The survival rate at 24 months of age in SYN1-F rats was 33·3 % greater compared with that of the control (Cont-F) group. To conclude, lifelong intervention with Synergy1 improved biological markers during ageing and survival rate (lifespan) of rats.

Glycaemic responses to the dextrin NUTRIOSE®6 (Dex) and the MALTISORB® maltitol (Mal) have been studied previously but their effects on vigilance and cognitive performances are still not known. The present study assesses dose-related glycaemic responses following Dex administration and the hypothesis that Dex and Mal could modulate the glycaemic response, improve vigilance under stress conditions and improve cognitive performances in rats. The glycaemic responses following Dex and corn syrup GLUCIDEX®IT 21 (CoS) solutions at 0·3, 0·5 and 1·0 g/kg body weight administered by oral administration (experiment 1) and glycaemic responses to three cereal bars (standard (CoS), Dex or Dex/Mal bar) (experiment 2) were evaluated. Rats having eaten cereal bars were submitted to vigilance and aversive light stimulus avoidance conditioning tests to assess their vigilance and cognitive performances. The first experiment showed that the glycaemic response to both products is dose-related and that CoS induced a glycaemic response three times higher than the Dex response. The second experiment showed the same glycaemic response for the three cereal bar-treated rats. Yet, an increase in the vigilance of Dex/Mal-treated rats as well as a better discrimination between two levers in the cognitive test for Dex- and Dex/Mal-treated rats were noticed. These results suggest that the glycaemic response is not the only factor to be considered in predicting the efficiency of a food ingredient on vigilance and cognitive performances: these behaviours are improved after Dex- and Mal-prepared cereal bar ingestion whereas the glycaemic response does not differ from the CoS-prepared bar.

Numerous studies have indicated that increased vulnerability to oxidative stress may be the main factor involved in functional declines during normal and pathological ageing, and that antioxidant agents, such as polyphenols, may improve or prevent these deficits. We examined whether 1-year administration of a cocoa polyphenolic extract (Acticoa powder), orally delivered at the dose of 24 mg/kg per d between 15 and 27 months of age, affects the onset of age-related cognitive deficits, urinary free dopamine levels and lifespan in old Wistar-Unilever rats. Acticoa powder improved cognitive performances in light extinction and water maze paradigms, increased lifespan and preserved high urinary free dopamine levels. These results suggest that Acticoa powder may be beneficial in retarding age-related brain impairments, including cognitive deficits in normal ageing and perhaps neurodegenerative diseases. Further studies are required to elucidate the mechanisms of cocoa polyphenols in neuroprotection and to explore their effects in man.

The behavioural and cognitive effects of oligofructose-enriched inulin at the doses of 5 and 10% in the diet, orally ingested daily during 2 weeks, wereinvestigated using a functional observational battery (FOB) and the light extinction test in male Wistar rats. Control rats received a standard diet and were tested in the same test situations. The behavioural effects were assessed 2 d before and 14 d after the beginning of the treatment period and the cognitive effects were investigated after the administration period by lever-pressing activity and learning discrimination using the light extinction test paradigm. In general, the study demonstrated that oligofructose-enriched inulin at 5% in the diet, and particularly at 10% in the diet, caused relaxing-like effects, stimulated and increased the general activity and interest of the rats to the test environment. In addition, both doses of oligofructose-enriched inulin showed significant effects on learning discrimination in male rats, in comparison with the control diet. These results suggest that oligofructose-enriched inulin, particularly at the dose of 10 %, improves cognitive performances in the light extinction test and the well-being of male rats using the FOB.

La dosimétrie individuelle présente plusieurs difficultés dues aux différences des réponses en énergie des dosimètres. Dans ce travail, nous proposons un dosimètre individuel réglementaire pour la surveillance radiologique des personnes soumises à l'exposition neutronique, autour du futur réacteur de recherche de type TRIGA Mark II du Maroc. L'exposition aux neutrons n'aura lieu qu'épisodiquement et les doses reçues devraient rester faibles. Afin de choisir convenablement un dosimètre individuel de neutrons, nous avons étudié deux systèmes : le détecteur à bulles et le détecteur solide de traces nucléaires PADC2 (CR-39$^{\mbox{\tiny\textregistered}}$). Vu les limitations imputées aux propriétés dosimétriques des différents dosimètres actuellement employés, une étude comparative approfondie est nécessaire en vue de disposer d'un dosimètre individuel convenable. Cette étude s'inscrit dans le contexte marocain : absence d'installations pour réaliser des tests, un nombre restreint de travailleurs opérant dans des zones spécifiques pourrait être soumis à l'exposition neutronique, contraintes économiques, champ neutronique souvent mixte et la réglementation qui impose le port d'un dosimètre individuel dans une zone contrôlée. En raison de ses caractéristiques dosimétriques et de son prix, le dosimètre de type CR-39 peut être une bonne solution comme dosimètre individuel passif de neutrons autour du réacteur TRIGA. Le dosimètre à bulles, permettant d'instaurer la démarche ALARA, serait utilisé comme dosimètre individuel complémentaire bien adapté à la dosimétrie opérationnelle.

Highly transparent undoped and indium doped ZnO thin films have been grown on glass substrates by using the spray pyrolysis process. Conditions of preparation have been optimized to get good quality and reproducible films with required properties. Polycrystalline films with an hexagonal Wurtzite-type structure were easily obtained under the optimum spraying conditions. Both of samples have shown high transmission coefficient in the visible and infrared wavelength range with sharp absorption edge around 380 nm which closely corresponds to the intrinsic band-gap of ZnO (3.2 eV). Orientation and crystallites size were remarkably modified by deposition temperature and indium doping.

The evolution of the reaction between the binary graphitide KC8 and CoCl2 dissolved in anhydrous tetrahydrofuran (THF) has been investigated by in situ x-ray diffraction (XRD). During the reaction and whatever the host graphite (powder or HOPG), the first stage graphite intercalation compounds K(THF)2.5C24 and K(THF)1.7C24 are first formed and then transformed into higher stages. Finally the matrix is exfoliated and the phases identified are graphite, metallic cobalt, and KCl. Analyses by Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) clearly show that the products are mainly located at the edge planes of the graphite, indicating that the electronic exchange occurs at the edge of the graphene layers. It is now clear that graphite-cobalt intercalation compounds cannot be obtained by this method.