184 resultados para Conditioned Fear


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Needle-free procedures are very attractive ways to deliver vaccines because they diminish the risk of contamination and may reduce local reactions, pain or pain fear especially in young children with a consequence of increasing the vaccination coverage for the whole population. For this purpose, the possible development of a mucosal malaria vaccine was investigated. Intranasal immunization was performed in BALB/c mice using a well-studied Plasmodium berghei model antigen derived from the circumsporozoite protein with the modified heat-labile toxin of Escherichia coli (LTK63), which is devoid of any enzymatic activity compared to the wild type form. Here, we show that intranasal administration of the two compounds activates the T and B cell immune response locally and systemically. In addition, a total protection of mice is obtained upon a challenge with live sporozoites.

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La présente étude est à la fois une évaluation du processus de la mise en oeuvre et des impacts de la police de proximité dans les cinq plus grandes zones urbaines de Suisse - Bâle, Berne, Genève, Lausanne et Zurich. La police de proximité (community policing) est à la fois une philosophie et une stratégie organisationnelle qui favorise un partenariat renouvelé entre la police et les communautés locales dans le but de résoudre les problèmes relatifs à la sécurité et à l'ordre public. L'évaluation de processus a analysé des données relatives aux réformes internes de la police qui ont été obtenues par l'intermédiaire d'entretiens semi-structurés avec des administrateurs clés des cinq départements de police, ainsi que dans des documents écrits de la police et d'autres sources publiques. L'évaluation des impacts, quant à elle, s'est basée sur des variables contextuelles telles que des statistiques policières et des données de recensement, ainsi que sur des indicateurs d'impacts construit à partir des données du Swiss Crime Survey (SCS) relatives au sentiment d'insécurité, à la perception du désordre public et à la satisfaction de la population à l'égard de la police. Le SCS est un sondage régulier qui a permis d'interroger des habitants des cinq grandes zones urbaines à plusieurs reprises depuis le milieu des années 1980. L'évaluation de processus a abouti à un « Calendrier des activités » visant à créer des données de panel permettant de mesurer les progrès réalisés dans la mise en oeuvre de la police de proximité à l'aide d'une grille d'évaluation à six dimensions à des intervalles de cinq ans entre 1990 et 2010. L'évaluation des impacts, effectuée ex post facto, a utilisé un concept de recherche non-expérimental (observational design) dans le but d'analyser les impacts de différents modèles de police de proximité dans des zones comparables à travers les cinq villes étudiées. Les quartiers urbains, délimités par zone de code postal, ont ainsi été regroupés par l'intermédiaire d'une typologie réalisée à l'aide d'algorithmes d'apprentissage automatique (machine learning). Des algorithmes supervisés et non supervisés ont été utilisés sur les données à haute dimensionnalité relatives à la criminalité, à la structure socio-économique et démographique et au cadre bâti dans le but de regrouper les quartiers urbains les plus similaires dans des clusters. D'abord, les cartes auto-organisatrices (self-organizing maps) ont été utilisées dans le but de réduire la variance intra-cluster des variables contextuelles et de maximiser simultanément la variance inter-cluster des réponses au sondage. Ensuite, l'algorithme des forêts d'arbres décisionnels (random forests) a permis à la fois d'évaluer la pertinence de la typologie de quartier élaborée et de sélectionner les variables contextuelles clés afin de construire un modèle parcimonieux faisant un minimum d'erreurs de classification. Enfin, pour l'analyse des impacts, la méthode des appariements des coefficients de propension (propensity score matching) a été utilisée pour équilibrer les échantillons prétest-posttest en termes d'âge, de sexe et de niveau d'éducation des répondants au sein de chaque type de quartier ainsi identifié dans chacune des villes, avant d'effectuer un test statistique de la différence observée dans les indicateurs d'impacts. De plus, tous les résultats statistiquement significatifs ont été soumis à une analyse de sensibilité (sensitivity analysis) afin d'évaluer leur robustesse face à un biais potentiel dû à des covariables non observées. L'étude relève qu'au cours des quinze dernières années, les cinq services de police ont entamé des réformes majeures de leur organisation ainsi que de leurs stratégies opérationnelles et qu'ils ont noué des partenariats stratégiques afin de mettre en oeuvre la police de proximité. La typologie de quartier développée a abouti à une réduction de la variance intra-cluster des variables contextuelles et permet d'expliquer une partie significative de la variance inter-cluster des indicateurs d'impacts avant la mise en oeuvre du traitement. Ceci semble suggérer que les méthodes de géocomputation aident à équilibrer les covariables observées et donc à réduire les menaces relatives à la validité interne d'un concept de recherche non-expérimental. Enfin, l'analyse des impacts a révélé que le sentiment d'insécurité a diminué de manière significative pendant la période 2000-2005 dans les quartiers se trouvant à l'intérieur et autour des centres-villes de Berne et de Zurich. Ces améliorations sont assez robustes face à des biais dus à des covariables inobservées et covarient dans le temps et l'espace avec la mise en oeuvre de la police de proximité. L'hypothèse alternative envisageant que les diminutions observées dans le sentiment d'insécurité soient, partiellement, un résultat des interventions policières de proximité semble donc être aussi plausible que l'hypothèse nulle considérant l'absence absolue d'effet. Ceci, même si le concept de recherche non-expérimental mis en oeuvre ne peut pas complètement exclure la sélection et la régression à la moyenne comme explications alternatives. The current research project is both a process and impact evaluation of community policing in Switzerland's five major urban areas - Basel, Bern, Geneva, Lausanne, and Zurich. Community policing is both a philosophy and an organizational strategy that promotes a renewed partnership between the police and the community to solve problems of crime and disorder. The process evaluation data on police internal reforms were obtained through semi-structured interviews with key administrators from the five police departments as well as from police internal documents and additional public sources. The impact evaluation uses official crime records and census statistics as contextual variables as well as Swiss Crime Survey (SCS) data on fear of crime, perceptions of disorder, and public attitudes towards the police as outcome measures. The SCS is a standing survey instrument that has polled residents of the five urban areas repeatedly since the mid-1980s. The process evaluation produced a "Calendar of Action" to create panel data to measure community policing implementation progress over six evaluative dimensions in intervals of five years between 1990 and 2010. The impact evaluation, carried out ex post facto, uses an observational design that analyzes the impact of the different community policing models between matched comparison areas across the five cities. Using ZIP code districts as proxies for urban neighborhoods, geospatial data mining algorithms serve to develop a neighborhood typology in order to match the comparison areas. To this end, both unsupervised and supervised algorithms are used to analyze high-dimensional data on crime, the socio-economic and demographic structure, and the built environment in order to classify urban neighborhoods into clusters of similar type. In a first step, self-organizing maps serve as tools to develop a clustering algorithm that reduces the within-cluster variance in the contextual variables and simultaneously maximizes the between-cluster variance in survey responses. The random forests algorithm then serves to assess the appropriateness of the resulting neighborhood typology and to select the key contextual variables in order to build a parsimonious model that makes a minimum of classification errors. Finally, for the impact analysis, propensity score matching methods are used to match the survey respondents of the pretest and posttest samples on age, gender, and their level of education for each neighborhood type identified within each city, before conducting a statistical test of the observed difference in the outcome measures. Moreover, all significant results were subjected to a sensitivity analysis to assess the robustness of these findings in the face of potential bias due to some unobserved covariates. The study finds that over the last fifteen years, all five police departments have undertaken major reforms of their internal organization and operating strategies and forged strategic partnerships in order to implement community policing. The resulting neighborhood typology reduced the within-cluster variance of the contextual variables and accounted for a significant share of the between-cluster variance in the outcome measures prior to treatment, suggesting that geocomputational methods help to balance the observed covariates and hence to reduce threats to the internal validity of an observational design. Finally, the impact analysis revealed that fear of crime dropped significantly over the 2000-2005 period in the neighborhoods in and around the urban centers of Bern and Zurich. These improvements are fairly robust in the face of bias due to some unobserved covariate and covary temporally and spatially with the implementation of community policing. The alternative hypothesis that the observed reductions in fear of crime were at least in part a result of community policing interventions thus appears at least as plausible as the null hypothesis of absolutely no effect, even if the observational design cannot completely rule out selection and regression to the mean as alternative explanations.

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Les laves torrentielles sont l'un des vecteurs majeurs de sédiments en milieu montagneux. Leur comportement hydrogéomorphologique est contrôlé par des facteurs géologique, géomorphologique, topographique, hydrologique, climatique et anthropique. Si, en Europe, la recherche s'est plus focalisée sur les aspects hydrologiques que géomorphologiques de ces phénomènes, l'identification des volumes de sédiments potentiellement mobilisables au sein de petits systèmes torrentiels et des processus responsables de leur transfert est d'une importance très grande en termes d'aménagement du territoire et de gestion des dangers naturels. De plus, une corrélation entre des événements pluviométriques et l'occurrence de laves torrentielles n'est pas toujours établie et de nombreux événements torrentiels semblent se déclencher lorsqu'un seuil géomorphologique intrinsèque (degré de remplissage du chenal) au cours d'eau est atteint.Une méthodologie pragmatique a été développée pour cartographier les stocks sédimentaires constituant une source de matériaux pour les laves torrentielles, comme outil préliminaire à la quantification des volumes transportés par ces phénomènes. La méthode s'appuie sur des données dérivées directement d'analyses en environnement SIG réalisées sur des modèles numériques d'altitude de haute précision, de mesures de terrain et d'interprétation de photographies aériennes. La méthode a été conçue pour évaluer la dynamique des transferts sédimentaires, en prenant en compte le rôle des différents réservoirs sédimentaires, par l'application du concept de cascade sédimentaire sous un angle cartographique.Les processus de transferts sédimentaires ont été étudiés dans deux bassins versants des Alpes suisses (torrent du Bruchi, à Blatten beiNaters et torrent du Meretschibach, à Agarn). La cartographie géomorphologique a été couplée avec des mesures complémentaires permettant d'estimer les flux sédimentaires et les taux d'érosion (traçages de peinture, piquets de dénudation et utilisation du LiDAR terrestre). La méthode proposée se révèle innovatrice en comparaison avec la plupart des systèmes de légendes géomorphologiques existants, qui ne sont souvent pas adaptés pour cartographier de manière satisfaisante les systèmes géomorphologiques complexes et actifs que sont les bassins torrentiels. L'intérêt de cette méthode est qu'elle permet l'établissement d'une cascade sédimentaire, mais uniquement pour des systèmes où l'occurrence d'une lave torrentielle est contrôlé par le degré de remplissage en matériaux du chenal. Par ailleurs, le produit cartographique ne peut être directement utilisé pour la création de cartes de dangers - axées sur les zones de dépôt - mais revêt un intérêt pour la mise en place de mesures de correction et pour l'installation de systèmes de monitoring ou d'alerte.La deuxième partie de ce travail de recherche est consacrée à la cartographie géomorphologique. Une analyse a porté sur un échantillon de 146 cartes ou systèmes de légende datant des années 1950 à 2009 et réalisés dans plus de 40 pays. Cette analyse a permis de mettre en évidence la diversité des applications et des techniques d'élaboration des cartes géomorphologiques. - Debris flows are one of the most important vectors of sediment transfer in mountainous areas. Their hydro-geomorphological behaviour is conditioned by geological, geomorphological, topographical, hydrological, climatic and anthropic factors. European research in torrential systems has focused more on hydrological processes than on geomorphological processes acting as debris flow triggers. Nevertheless, the identification of sediment volumes that have the potential to be mobilised in small torrential systems, as well as the recognition of processes responsible for their mobilisation and transfer within the torrential system, are important in terms of land-use planning and natural hazard management. Moreover, a correlation between rainfall and debris flow occurrence is not always established and a number of debris flows seems to occur when a poorly understood geomorphological threshold is reached.A pragmatic methodology has been developed for mapping sediment storages that may constitute source zone of bed load transport and debris flows as a preliminary tool before quantifying their volumes. It is based on data directly derived from GIS analysis using high resolution DEM's, field measurements and aerial photograph interpretations. It has been conceived to estimate sediment transfer dynamics, taking into account the role of different sediment stores in the torrential system applying the concept of "sediment cascade" in a cartographic point of view.Sediment transfer processes were investigated in two small catchments in the Swiss Alps (Bruchi torrent, Blatten bei Naters and Meretschibach torrent, Agarn). Thorough field geomorphological mapping coupled with complementary measurements were conducted to estimate sediment fluxes and denudation rates, using various methods (reference coloured lines, wooden markers and terrestrial LiDAR). The proposed geomorphological mapping methodology is quite innovative in comparison with most legend systems that are not adequate for mapping active and complex geomorphological systems such as debris flow catchments. The interest of this mapping method is that it allows the concept of sediment cascade to be spatially implemented but only for supply-limited systems. The map cannot be used directly for the creation of hazard maps, focused on the deposition areas, but for the design of correction measures and the implementation of monitoring and warning systems.The second part of this work focuses on geomorphological mapping. An analysis of a sample of 146 (extracts of) maps or legend systems dating from the middle of the 20th century to 2009 - realised in more than 40 different countries - was carried out. Even if this study is not exhaustive, it shows a clear renewed interest for the discipline worldwide. It highlights the diversity of applications, techniques (scale, colours and symbology) used for their conception.

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Introduction.- Pain and beliefs have an influence on the patient's course in rehabilitation and their relationships are complex. The aim of this study was to understand the relationships between pain at admission and the evolution of beliefs during rehabilitation as well as the relationships between pain and beliefs one year after rehabilitation.Patients and methods.- Six hundred and thirty-one consecutive patients admitted in rehabilitation after musculoskeletal trauma, were included and assessed at admission, at discharge and one year after discharge. Pain was measured by VAS (Visual Analogical Scale) and beliefs by judgement on Lickert scales. Four kinds of beliefs were evaluated: fear of a severe origin of pain, fear of movement, fear of pain and feeling of distress (loss of control). The association between pain and beliefs was assessed by logistic regressions, adjusted for gender, age, native language, education and bio-psycho-social complexity.Results.- At discharge, 44% of patients felt less distressed by pain, 34% are reinsured with regard to their fear of a severe origin of pain, 38% have less fear of pain and 33% have less fear of movement. The higher the pain at admission, the higher the probability that the distress diminished, this being true up to a threshold (70 mm/100) beyond which there was a plateau. At one year, the higher the pain, the more dysfunctional the fears.Discussion.- The relationships between pain and beliefs are complex and may change all along rehabilitation. During hospitalization, one could hope that the patient would be reinsured and would gain self-control again, if pain does not exceed a certain threshold. After one year, high pain increases the risk of dysfunctional beliefs. For clinical practice, these data suggest to think in terms of the more accessible "entrance door", act against pain and/or against beliefs, adpated to each patient.

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Objectives This paper reports on a longitudinal qualitative study exploring concerns of 60 patients before and after transplantation. Methods Semi-structured interviews were conducted without time constraints in a protected space out of the hospital. Qualitative analysis was performed. Results Prior to transplantation, all patients talked freely about negative feelings, stigmatisation, being misunderstood by others, loneliness and culpability caused by increasing physical dependency or abandoned roles. They mentioned alternative ways to cope (magic, spirituality), and even expressed their right to let go. In a subset of 13 patients, significant ones allowed themselves in the interview, or were integrated on the request of the patients. In this modified setting, two illness-worlds were confronted. If common themes were mentioned (e.g., modified life plans, restricted space, physical and psychological barriers), they were experienced differently. Fear of transplantation or guilt towards the donors was overtly expressed, often for the first time. Mutual hiding of anxiety in order to protect loved ones or to prevent loss of control was disclosed. The significant ones talked about accumulated stress and exhaustion related to the physical degradation of the patient, fear of the unpredictable evolution of illness and financial problems, and stressed their difficulty to adapt adequately to the fluctuating state of the patient. After transplantation, other themes emerged, where difficulty in disclosure was observed: intensive care and near death experiences, being a transplanted person, debt to the donor and his/her family, fear of rejection. Conclusions With the self-imposed strategy of hiding concerns to protect one another, a discrepancy between two illness-worlds was created. When concerns were confronted during the interviews, a new mutual understanding emerged. Patients and their families stated the need for sharing concerns in the course of illness.

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BACKGROUND: Loss of balance confidence is a frequent condition that affects 20-75% of community-dwelling older persons. Although a recent fall is a common trigger, loss of balance confidence also appears independent of previous experience with falls. Maintaining or improving balance confidence is important to avoid unnecessary, self-imposed restrictions of activity and subsequent disability. Holding another person's hand or using an assistive device while walking are simple interventions that are used naturally to address poor balance confidence in daily life. However, more complex interventions have also been developed and tested to achieve more sustained improvement in balance confidence. OBJECTIVES: This review describes interventions that have been tested to improve balance confidence in older community-dwelling persons. METHODS: Based on 2 recent systematic reviews, an additional search for literature was performed to update current information on interventions aiming at balance confidence improvement. Interventions were classified as those directly aimed at increasing balance confidence or not, and further stratified into those using monofactorial or multifactorial approaches. RESULTS: A total of 46 randomized controlled trials were identified. Five of the 8 interventions that directly targeted balance confidence showed benefits. Among those, multicomponent behavioral group interventions provided the most robust evidence of benefits in improving balance confidence and in decreasing activity avoidance. Among interventions not directly aiming at balance confidence improvement (11/21 studies with benefits), exercise (including tai chi) appears as the most promising monofactorial intervention. Nine of the 17 multifactorial fall prevention programs showed an effect on balance confidence, exercise being a main component in 7 of these 9 studies. Interventions that targeted elderly persons reporting poor balance confidence and/or those at risk for falls seemed more likely to be beneficial. CONCLUSIONS: Positive and sometimes sustained improvement in balance confidence can be achieved by various interventions among community-dwelling elderly persons. The effect of these interventions on activity restriction associated with poor balance confidence have been less well studied, but some studies also suggest potential benefits.

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Due to various contexts and processes, forensic science communities may have different approaches, largely influenced by their criminal justice systems. However, forensic science practices share some common characteristics. One is the assurance of a high (scientific) quality within processes and practices. For most crime laboratory directors and forensic science associations, this issue is conditioned by the triangle of quality, which represents the current paradigm of quality assurance in the field. It consists of the implementation of standardization, certification, accreditation, and an evaluation process. It constitutes a clear and sound way to exchange data between laboratories and enables databasing due to standardized methods ensuring reliable and valid results; but it is also a means of defining minimum requirements for practitioners' skills for specific forensic science activities. The control of each of these aspects offers non-forensic science partners the assurance that the entire process has been mastered and is trustworthy. Most of the standards focus on the analysis stage and do not consider pre- and post-laboratory stages, namely, the work achieved at the investigation scene and the evaluation and interpretation of the results, intended for intelligence beneficiaries or for court. Such localized consideration prevents forensic practitioners from identifying where the problems really lie with regard to criminal justice systems. According to a performance-management approach, scientific quality should not be restricted to standardized procedures and controls in forensic science practice. Ensuring high quality also strongly depends on the way a forensic science culture is assimilated (into specific education training and workplaces) and in the way practitioners understand forensic science as a whole.

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In this paper, we develop a data-driven methodology to characterize the likelihood of orographic precipitation enhancement using sequences of weather radar images and a digital elevation model (DEM). Geographical locations with topographic characteristics favorable to enforce repeatable and persistent orographic precipitation such as stationary cells, upslope rainfall enhancement, and repeated convective initiation are detected by analyzing the spatial distribution of a set of precipitation cells extracted from radar imagery. Topographic features such as terrain convexity and gradients computed from the DEM at multiple spatial scales as well as velocity fields estimated from sequences of weather radar images are used as explanatory factors to describe the occurrence of localized precipitation enhancement. The latter is represented as a binary process by defining a threshold on the number of cell occurrences at particular locations. Both two-class and one-class support vector machine classifiers are tested to separate the presumed orographic cells from the nonorographic ones in the space of contributing topographic and flow features. Site-based validation is carried out to estimate realistic generalization skills of the obtained spatial prediction models. Due to the high class separability, the decision function of the classifiers can be interpreted as a likelihood or susceptibility of orographic precipitation enhancement. The developed approach can serve as a basis for refining radar-based quantitative precipitation estimates and short-term forecasts or for generating stochastic precipitation ensembles conditioned on the local topography.

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Integrin-mediated force application induces a conformational change in latent TGF-β1 that leads to the release of the active form of the growth factor from the extracellular matrix (ECM). Mechanical activation of TGF-β1 is currently understood as an acute process that depends on the contractile force of cells. However, we show that ECM remodeling, preceding the activation step, mechanically primes latent TGF-β1 akin to loading a mechanical spring. Cell-based assays and unique strain devices were used to produce a cell-derived ECM of controlled organization and prestrain. Mechanically conditioned ECM served as a substrate to measure the efficacy of TGF-β1 activation after cell contraction or direct force application using magnetic microbeads. The release of active TGF-β1 was always higher from prestrained ECM as compared with unorganized and/or relaxed ECM. The finding that ECM prestrain regulates the bioavailability of TGF-β1 is important to understand the context of diseases that involve excessive ECM remodeling, such as fibrosis or cancer.

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While studies on triggers and outcomes of Psychological Momentum (PM) exist, little is known about the dynamics by which PM emerges and develops over time. Based on video-assisted recalls of PM experiences in table tennis and swimming competitions, this research qualitatively explored the triggering processes, contents, and the development of PM over time. PM was found to be triggered by mechanisms of dissonance, consonance, or fear of not winning. During the PM experience, participants reported a variety of perceptions, affects and emotions, cognitions, and behaviors, and PM was found to develop through processes of amplification that sometimes ended with a reduction of efforts when the victory or defeat was perceived as certain. These findings are discussed in light of theories on self-regulation and reactance-helplessness. From a practical standpoint, achievement goal-based strategies are suggested, since mastery-approach goals were found to be endorsed to maintain positive PM and overcome negative PM

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IL-15 has recently been shown to induce the differentiation of functional dendritic cells (DCs) from human peripheral blood monocytes. Since DCs lay in close proximity to epithelial cells in the airway mucosa, we investigated whether airway epithelial cells release IL-15 in response to inflammatory stimuli and thereby induce differentiation and maturation of DCs. Alveolar (A549) and bronchial (BEAS-2B) epithelial cells produced IL-15 spontaneously and in a time- and dose-dependent manner after stimulation with IL-1beta, IFN-gamma, or TNF-alpha. Airway epithelial cell supernatants induced an increase of IL-15Ralpha gene expression in ex vivo monocytes, and stimulated DCs enhanced their IL-15Ralpha gene expression up to 300-fold. Airway epithelial cell-conditioned media induced the differentiation of ex vivo monocytes into partially mature DCs (HLA-DR+, DC-SIGN+, CD14+, CD80-, CD83+, CD86+, CCR3+, CCR6(+), CCR7-). Based on their phenotypic (CD123+, BDCA2+, BDCA4+, BDCA1(-), CD1a-) and functional properties (limited maturation upon stimulation with LPS and limited capacity to induce T cell proliferation), these DCs resembled plasmacytoid DCs. The effects of airway epithelial cell supernatants were largely blocked by a neutralizing monoclonal antibody to IL-15. Thus, our results demonstrate that airway epithelial cell-conditioned media have the capacity to differentiate monocytes into functional DCs, a process substantially mediated by epithelial-derived IL-15.

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Acid-sensing ion channels (ASICs) are non-voltage-gated sodium channels activated by an extracellular acidification. They are widely expressed in neurons of the central and peripheral nervous system. ASICs have a role in learning, the expression of fear, in neuronal death after cerebral ischemia, and in pain sensation. Tissue damage leads to the release of inflammatory mediators. There is a subpopulation of sensory neurons which are able to release the neuropeptides calcitonin gene-related peptide (CGRP) and substance P (SP). Neurogenic inflammation refers to the process whereby peripheral release of the neuropeptides CGRP and SP induces vasodilation and extravasation of plasma proteins, respectively. Our laboratory has previously shown that calcium-permeable homomeric ASIC1a channels are present in a majority of CGRP- or SP-expressing small diameter sensory neurons. In the first part of my thesis, we tested the hypothesis that a local acidification can produce an ASIC-mediated calcium-dependant neuropeptide secretion. We have first verified the co-expression of ASICs and CGRP/SP using immunochemistry and in-situ hybridization on dissociated rat dorsal root ganglion (DRG) neurons. We found that most CGRP/SP-positive neurons also expressed ASIC1a and ASIC3 subunits. Calcium imaging experiments with Fura-2 dye showed that an extracellular acidification can induce an increase of intracellular Ca2+ concentration, which is essential for secretion. This increase of intracellular Ca2+ concentration is, at least in some cells, ASIC-dependent, as it can be prevented by amiloride, an ASIC antagonist, and by Psalmotoxin (PcTx1), a specific ASIC1a antagonist. We identified a sub-population of neurons whose acid-induced Ca2+ entry was completely abolished by amiloride, an amiloride-resistant population which does not express ASICs, but rather another acid-sensing channel, possibly transient receptor potential vanilloïde 1 (TRPV1), and a population expressing both H+-gated channel types. Voltage-gated calcium channels (Cavs) may also mediate Ca2+ entry. Co-application of the Cavs inhibitors (ω-conotoxin MVIIC, Mibefradil and Nifedipine) reduced the Ca2+ increase in neurons expressing ASICs during an acidification to pH 6. This indicates that ASICs can depolarise the neuron and activate Cavs. Homomeric ASIC1a are Ca2+-permeable and allow a direct entry of Ca2+ into the cell; other ASICs mediate an indirect entry of Ca2+ by inducing a membrane depolarisation that activates Cavs. We showed with a secretion assay that CGRP secretion can be induced by extracellular acidification in cultured rat DRG neurons. Amiloride and PcTx1 were not able to inhibit the secretion at acidic pH, but BCTC, a TRPV1 inhibitor was able to decrease the secretion induced by an extracellular acidification in our in vitro secretion assay. In conclusion, these results show that in DRG neurons a mild extracellular acidification can induce a calcium-dependent neuropeptide secretion. Even if our data show that ASICs can mediate an increase of intracellular Ca2+ concentration, this appears not to be sufficient to trigger neuropeptide secretion. TRPV1, a calcium channel whose activation induces a sustained current - in contrary of ASICs - played in our experimental conditions a predominant role in neurosecretion. In the second part of my thesis, we focused on the role of ASICs in neuropathic pain. We used the spared nerve injury (SNI) model which consists in a nerve injury that induces symptoms of neuropathic pain such as mechanical allodynia. We have previously shown that the SNI model modifies ASIC currents in dissociated rat DRG neurons. We hypothesized that ASICs could play a role in the development of mechanical allodynia. The SNI model was performed on ASIC1a, -2, and -3 knock-out mice and wild type littermates. We measured mechanical allodynia on these mice with calibrated von Frey filaments. There were no differences between the wild-type and the ASIC1, or ASIC2 knockout mice. ASIC3 null mice were less sensitive than wild type mice at 21 day after SNI, indicating a role for ASIC3. Finally, to investigate other possible roles of ASICs in the perception of the environment, we measured the baseline heat responses. We used two different models; the tail flick model and the hot plate model. ASIC1a null mice showed increased thermal allodynia behaviour in the hot plate test at three different temperatures (49, 52, 55°C) compared to their wild type littermates. On the contrary, ASIC2 null mice showed reduced thermal allodynia behaviour in the hot plate test compared to their wild type littermates at the three same temperatures. We conclude that ASIC1a and ASIC2 in mice can play a role in temperature sensing. It is currently not understood how ASICs are involved in temperature sensing and what the reason for the opposed effects in the two knockout models is.

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To explore, for the first time, the impact of job insecurity on sexual desire. Cross-sectional analysis of a nationally representative sample of 7247 individuals aged 20-64 years working as full or part-time employees in Switzerland. The logistic regression analysis showed that workers aged 20-49 years perceiving high levels of job insecurity are exposed to a significantly higher risk of decrease of sexual desire compared to the reference group. The risk is 53% higher among men (OR 1.53; 95% CI 1.16-2.01) and 47% for woman (OR 1.47; 1.13-1.91). No increased risk was found for employees aged 50-64 years old. An increasing fear of job loss is associated with a deterioration in sexual desire. These first preliminary findings should promote further epidemiological and clinical prospective studies on the impact of job insecurity on intimate relationships and sexual dysfunction.

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BACKGROUND: Human speech is greatly influenced by the speakers' affective state, such as sadness, happiness, grief, guilt, fear, anger, aggression, faintheartedness, shame, sexual arousal, love, amongst others. Attentive listeners discover a lot about the affective state of their dialog partners with no great effort, and without having to talk about it explicitly during a conversation or on the phone. On the other hand, speech dysfunctions, such as slow, delayed or monotonous speech, are prominent features of affective disorders. METHODS: This project was comprised of four studies with healthy volunteers from Bristol (English: n = 117), Lausanne (French: n = 128), Zurich (German: n = 208), and Valencia (Spanish: n = 124). All samples were stratified according to gender, age, and education. The specific study design with different types of spoken text along with repeated assessments at 14-day intervals allowed us to estimate the 'natural' variation of speech parameters over time, and to analyze the sensitivity of speech parameters with respect to form and content of spoken text. Additionally, our project included a longitudinal self-assessment study with university students from Zurich (n = 18) and unemployed adults from Valencia (n = 18) in order to test the feasibility of the speech analysis method in home environments. RESULTS: The normative data showed that speaking behavior and voice sound characteristics can be quantified in a reproducible and language-independent way. The high resolution of the method was verified by a computerized assignment of speech parameter patterns to languages at a success rate of 90%, while the correct assignment to texts was 70%. In the longitudinal self-assessment study we calculated individual 'baselines' for each test person along with deviations thereof. The significance of such deviations was assessed through the normative reference data. CONCLUSIONS: Our data provided gender-, age-, and language-specific thresholds that allow one to reliably distinguish between 'natural fluctuations' and 'significant changes'. The longitudinal self-assessment study with repeated assessments at 1-day intervals over 14 days demonstrated the feasibility and efficiency of the speech analysis method in home environments, thus clearing the way to a broader range of applications in psychiatry. © 2014 S. Karger AG, Basel.

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Since the mid-1970s thoracic surgeons have used cricotracheal resection (CTR) in the adult population. Similar positive results have from then on been reported by different investigators using this technique. In contrast, otolaryngologists have typically used an anterior midline approach to the larynx and trachea for their laryngotracheal reconstructions (LTRs), both in adults and children. The fear of injury to the recurrent laryngeal nerve (RLN), the risk of a dehiscence of the anastomosis, and the interference with normal growth of the larynx in the pediatric age group were the main reasons put forward for not using a CTR for the cure of subglottic stenosis. In this article, we describe the similarities and differences in CTRs performed for adult and pediatric cases. The high rate (>90%) of success for severe pediatric SGS using CTR compares most favorably with LTR, which is still used in most otolaryngology departments. The reasons lie in the full resection of the stenosis and the restoration of a steady cartilaginous framework of the larynx and trachea with full mucosal lining on both sides of the anastomosis. Furthermore, CTR can be associated with a Rethi procedure for the cure of combined posterior glottic and subglottic stenoses. Good results from series of two different centers suggest that CTR will become the treatment of choice for pediatric severe SGS, as is presently the case in the adult population.