Cluster kernels for semisupervised classification of VHR urban images

In this paper, we present and apply a semisupervised support vector machine based on cluster kernels for the problem of very high resolution image classification. In the proposed setting, a base kernel working with labeled samples only is deformed by a likelihood kernel encoding similarities between unlabeled examples. The resulting kernel is used to train a standard support vector machine (SVM) classifier. Experiments carried out on very high resolution (VHR) multispectral and hyperspectral images using very few labeled examples show the relevancy of the method in the context of urban image classification. Its simplicity and the small number of parameters involved make it versatile and workable by unexperimented users.

Prévalence des troubles de l'humeur dans la maladie de Parkinson traitée par stimulation cérébrale profonde [Prevalence of mood disorders in Parkinson's disease patients treated with subthalamic nucleus deep brain stimulation].

Subthalamic nucleus deep brain stimulation (STN-DBS) is a recognized treatment for advanced and severe forms of Parkinson's Disease. The procedure improves motor signs and often allows a reduction of the medication. The impact of the procedure on cognitive and neuropsychiatric signs of the disease is more debated and there is an international consensus for the need of a multidisciplinary evaluation of patients undergoing such programs, including a neuropsychiatric assessment. We present a review of the literature as well as the experience at our centre focused on the short and long term outcome on mood following STN-DBS.

PsyCoLaUS: santé mentale et maladies cardiovasculaires: association fortuite [PsyCoLaus: mental disorders and cardiovascular diseases: spurious association?].

Cardio-vascular diseases (CVD), their well established risk factors (CVRF) and mental disorders are common and co-occur more frequently than would be expected by chance. However, the mechanisms underlying this association are still poorly understood. The main study questions of PsyCoLaus, the psychiatric arm of CoLaus, are: 1) Do mental disorders increase vulnerability to CVRF and CVD? 2) Do CVRF and CVD promote the development of mental disorders? 3) Do CVRF/ CVD and mental disorders share common pathogenetic processes? The longitudinal project adds a comprehensive psychiatric evaluation to the CoLaus investigation. A better understanding of the psychological, physiological and behavioral links underlying CVD/ CVRF and mental disorders will result in the development of more specific and efficient strategies of prevention and treatment for both psychiatric and CVD/CVRF, two major elements of burden of disease.

Patients presenting with somatic complaints in general practice : dépression, anxiety and somatoform disorders are frequent and associated with psychosocial stressors

RAPPORT DE SYNTHÈSE Introduction En médecine de premier recours, les plaintes physiques sont fréquemment associées à des troubles dépressifs, anxieux et somatoformes et peuvent les masquer. Il est fréquemment reporté que ces troubles mentaux ont tendance à être insuffisamment diagnostiqués. Par ailleurs, peu d'études ont été conduites en médecine de premier recours concernant la possible association entre facteurs de stress psychosociaux et troubles dépressifs, anxieux et somatoformes. Objectifs Les objectifs étaient de déterminer la prévalence des troubles dépressifs, anxieux et somatoformes chez des patients consultant avec une plainte physique en médecine de premier recours, ainsi que d'explorer la possible association entre ces troubles mentaux et des facteurs de stress psychosociaux. Méthodes Nous avons conduit une étude transversale, multicentrique parmi vingt et un cabinets médicaux en Suisse Romande et la Policlinique Médicale Universitaire de Lausanne. Les sujets étaient sélectionnés aléatoirement parmi des patients qui avaient présenté spontanément au moins une plainte physique et qui avaient consulté lors d'une demi- journée de consultation considérée pour l'étude. Les patients inclus ont rempli l'auto- questionnaire Patient Health Questionnaire (PHQ) entre novembre 2004 et juillet 2005. Nous avons utilisé la version française et validée du PHQ qui permet le diagnostic des principaux troubles mentaux selon les critères du DSM-IV et l'analyse de l'exposition aux facteurs de stress psychosociaux. Résultats Neuf cent dix-sept patients se présentant avec au moins une plainte physique ont été inclus. Le taux de troubles dépressifs, anxieux et somatoformes a été de 20,0% (intervalle de confiance [IC] à 95% = 17,4%-22,7%), 15,5% (IC 95% = 13,2%- 18,0%) et 15,1% (IC 95% = 12,8%~17,5%), respectivement. Les facteurs de stress psychosociaux ont été significativement associés aux troubles mentaux. Les patients avec une accumulation de facteurs de stress psychosociaux ont été le plus souvent déprimés, anxieux ou ont manifesté des troubles somatoformes, avec une augmentation par un facteur 2,2 (IC 95% = 2,0-2,5) pour chaque facteur additionnel. Conclusions Bien que la relation entre facteurs de stress psychosociaux et trouble dépressif soit bien établie, cette étude montre qu'il existe un lien entre ces facteurs de stress et les troubles dépressifs, anxieux et somatoformes. L'investigation de ces troubles mentaux chez des patients consultant avec un symptôme physique en médecine de premier recours est pertinente. D'autres explorations sont nécessaires pour investiguer le bénéfice potentiel d'une prise en charge intégrée des facteurs de stress psychosociaux sur la diminution des plaintes physiques et des troubles mentaux chez les patients que suivent les médecins de premier recours.

Personality disorders and the Five-Factor Model among French speakers in Africa and Europe

Objective: Several authors have suggested that Personality Disorders (PDs) might be more accurately described using a dimensional model instead of a categorical one. The aim of this study was to describe the relationship between PDs and the Five-Factor Model (FFM)-a dimensional model describing normal personality traits known for its invariance across cultures-in two different cultural settings. Method: Subjects from nine French-speaking African countries (n = 2,014) and from Switzerland (n = 697) completed both the French-version of the IPDE screening questionnaire, assessing the ten DSM-IV PDs, and the French-version of the NEO-PI-R, assessing the five domains and thirty facets of the FFM. Results: Correlations between PDs and the five domains of the FFM were similar in both samples. For example, Neuroticism was highly correlated with Borderline, Avoidant, and Dependent PDs in both Africa and Switzerland. The total rank-order correlation (rho) between the two correlation matrices was very high (rho = 0.93) and significant (P < 0.001), as were the rhos for all domains of the FFM and all PDs, except Paranoid and Dependent PDs. However, the rhos for PDs across facet-scales were all highly significant (P < 0.001). Moreover, 80% of Widiger and colleagues' predictions and 70 % of Lynam and Widiger's prototypes, concerning the relationship between PDs and the FFM, were confirmed in both samples. Conclusions: The relationship between PDs and the FFM was stable in two samples separated by a great cultural distance. These results suggest that a dimensional approach and in particular the FFM might be useful for describing PDs in a variety of cultural settings.

Le concept de test relationnel en psychothérapie: origine, développements et applications aux troubles de la personnalité = The test concept in psychotherapy: origins, developments and application to personality disorders

Le concept de test relationnel (test, en anglais ; Weiss et Sampson, 1986 [16]) est présenté. Ses origines dans les écrits de Freud sont brièvement retracées et son inscription dans la théorie des croyances pathogènes de Weiss présentée. Par ailleurs, les autres éléments de la théorie psychanalytique de Weiss sont présentés (buts thérapeutiques, obstacles, traumas, insight, test relationnel). Toutes ces étapes sont illustrées par des exemples tirés de la littérature. Un développement récent du concept de test relationnel est présenté et appliqué à la psychothérapie des troubles de la personnalité (Sachse, 2003 [14]). Finalement, les auteurs donnent deux brefs exemples de tests relationnels tirés de leur propre pratique de psychothérapeute et discutent des modèles en les comparant entre eux. Des conclusions concernant l'utilité du concept de test relationnel pour la pratique psychothérapeutique et la recherche en psychothérapie sont proposées. The test concept (Weiss and Sampson, 1986 [16]) is presented. Its origins in Freud's works are briefly evoked and its place within the theory of pathogenic beliefs by Weiss presented. We present also the remaining elements of Weiss' psychoanalytic theory which are objectives, obstacles, traumas and insight. Every step of the reflection is illustrated with case examples, drawn from the literature. A recent development of the test concept is presented and applied to the psychotherapy of personality disorders (Sachse, 2003 [14]). Finally, the authors give brief examples of tests having occurred in their own practice as psychotherapists and discuss the models by comparing them among each other. Conclusions are drawn concerning the usefulness of the test concept for psychotherapy practice and research.

Community introduction of practice parameters for autistic spectrum disorders: Advancing early recognition.

OBJECTIVES: Within a strong interdisciplinary framework, improvement in the quality of care for children with autistic spectrum disorders through a 2 year implementation program of Practice Parameters, aimed principally at improving early detection and intervention. METHOD: We developed Practice Parameters (PPs) for Pervasive Developmental Disorders and circulated the PPs to all child and adolescent psychiatrists practicing in the region. RESULTS: PP development and parallel information strategies resulted in a significant decrease of 1.5 years in the mean-age-at-diagnosis. However, further analysis indicated that improvement was only transient. CONCLUSION: Despite the encouraging improvement in mean-age-at-diagnosis 2 years after PP implementation, other indicators showed a failure to maintain the improvements. A systematic screening program would be the most reliable method to reinforce the PPs.

Neuroprotection for optic nerve disorders.

The concept that optic nerve fiber loss might be reduced by neuroprotection arose in the mid 1990s. The subsequent research effort, focused mainly on rodent models, has not yet transformed into a successful clinical trial, but provides mechanistic understanding of retinal ganglion cell death and points to potential therapeutic strategies. This review highlights advances made over the last year. In excitotoxicity and axotomy models retinal ganglion cell death has been shown to result from a complex interaction between retinal neurons and Müller glia, which release toxic molecules including tumor necrosis factor alpha. This counteracts neuroprotection by neurotrophins such as nerve growth factor, which bind to p75NTR receptors on Müller glia stimulating the toxic release. Another negative effect against neurotrophin-mediated protection involves the action of LINGO-1 at trkB brain-derived neurotrophic factor (BDNF) receptors, and BDNF neuroprotection is enhanced by an antagonist to LINGO-1. As an alternative to pharmacotherapy, retinal defences can be stimulated by exposure to infrared radiation. The mechanisms involved in glaucoma and other optic nerve disorders are being clarified in rodent models, focusing on retrograde degeneration following axonal damage, excitotoxicity and inflammatory/autoimmune mechanisms. Neuroprotective strategies are being refined in the light of the mechanistic understanding.

Genetics of narcolepsy and other major sleep disorders.

One third of the population is affected by a sleep disorder with a major social, medical, and economic impact. Although very little is known about the genetics of normal sleep, familial and twin studies indicate an important influence of genetic factors. Most sleep disorders run in families and in several of them the contribution of genetic factors is increasingly recognised. With recent advances in the genetics of narcolepsy and the role of the hypocretin/orexin system, the possibility that other gene defects may contribute to the pathophysiology of major sleep disorders is worth indepth investigation.