En quête de Perceval. Étude sur un mythe littéraire

Après avoir proposé une définition opératoire du mythe littéraire, et suggéré, sous l'étiquette de « mytholectures », un mode d'approche de cet objet, le travail se subdivise en deux grandes parties.La première, diachronique, cherche à sonder le devenir historique du mythe de Perceval, de Chrétien de Troyes à nos jours ; il s'agit essentiellement d'observer comment la valeur et le sens du mythe se sont élaborés progressivement au fil de ses reprises - comment chaque période, chaque auteur a rencontré le mythe sous un rapport singulier, susceptible de lui fournir un « miroir » qui reflète certaines de ses préoccupations et lui permette, parallèlement, de configurer son expérience du monde. Les principales étapes de ce parcours (qui touche à environ quatre-vingts auteurs) sont Richard Wagner et Julien Gracq.La seconde partie propose deux approches thématiques du mythe de Perceval : l'une d'elles est centrée sur la problématique familiale et les enjeux relationnels qui, de reprise en reprise, ne cessent d'être réinterprétés sous divers angles (dont Oedipe, cet « anti-Perceval », n'est jamais très loin). L'autre axe thématique s'intéresse à la propension marquée du mythe de Perceval à fonctionner comme modèle des deux pôles de l'activité littéraire que sont la lecture (quête de sens) et l'écriture (quête poétique) : divers « arts poétiques percevaliens » (de Wagner à Perec, en passant par Proust ou Handke) closent ainsi le parcours.

Basic Surface Properties of Mononuclear Cells from Didelphis marsupialis

The electrostatic surface charge and surface tension of mononuclear cells/monocytes obtained from young and adult marsupials (Didelphis marsupialis) were investigated by using cationized ferritin and colloidal iron hydroxyde, whole cell electrophoresis, and measurements of contact angles. Anionic sites were found distributed throughout the entire investigated cell surfaces. The results revealed that the anionic character of the cells is given by electrostatic charges corresponding to -18.8 mV (cells from young animals) and -29.3 mV (cells from adult animals). The surface electrostatic charge decreased from 10 to 65.2% after treatment of the cells with each one of trypsin, neuraminidase and phospholipase C. The hydrophobic nature of the mononuclear cell surfaces studied by using the contact angle method revealed that both young and adult cells possess cell surfaces of high hidrofilicity since the angles formed with drops of saline water were 42.5°and 40.8°, respectively. Treatment of the cells with trypsin or neuraminidase rendered their surfaces more hydrophobic, suggesting that sialic acid-containing glycoproteins are responsible for most of the hydrophilicity observed in the mononuclear cell surfaces from D. marsupialis.

Evaluation of the 3D symmetry of the knees when walking using na ambulatory inertia system: results 14 months after ACL Plasty.

Purpose of the study: Reconstruction of the anterior cruciate ligament (ACL) controls laxity but does not enable restoration of strictly normal 3D kinematics. The purpose of this study was to compare the kinematics of the pathological knee with that of the healthy knee after ACL plasty. This study applied a new ambulatory system using miniature captors. Material and method: Five patients with an isolated injury of the ACL participated in this study. The patients were assessed after injury (T1), at five months (T2), and at 14 months (T3) after surgery. The assessment included laxity (KT-1000), the IKDC score and the Lysholm score. The 3D angles of the knees were measured when walking 30 m on flat ground using a system composed of to small inertia units (3D accelerometer and 3D gyroscope) and a portable recorder. Functional settings were optimised and validating to ensure easy precise measurement of the 3D angles. Symmetry of the two knees was quantified using a symmetry index (SI) (difference in amplitude normalised in relation to mean amplitude) and the correlation coefficient CC. Results: Clinical indicators improved during the follow-up (IKDC T1: 3C, 2C; T2: 5B; T3: 2A, 3B; subjective IKD: 53-95; Lysholm 67-96). Mean laxity improved from 8.6m to 2.5 mm. The gait analysis showed increased symmetry in terms of amplitude for flexion-extension (SI: −17% at T1, −1% at T2, 1% at T3), and an increase in symmetry in terms of the rotation signature (CC: 0.16 at T1, 0.99 at T2, 0.99 at T3). There was no trend to varus-valgus. Discussion: This study demonstrates the clinical application of the new ambulatory system for measuring 3D angles of the knee joint. Joint symmetry increased after ACL plasty but still showed some perturbation at 14 months. The results observed here are in agreement with the literature. Other patients and other types of gait are being analysed. Conclusion: This portable system allows gait analysis outside the laboratory, before and after ACL injury. It is very useful for follow-up after surgery.

Les symbioses industrielles : une nouvelle stratégie pour l'amélioration de l'utilisation des ressources matérielles et énergétiques par les activités économiques

RésuméCette thèse traite d'un domaine d'application de l'écologie industrielle, les symbioses industrielles, comme stratégie d'amélioration de la consommation des ressources matérielles et énergétiques et de la gestion des déchets par les activités économiques. Les symbioses industrielles cherchent à créer de nouvelles collaborations directement entre les acteurs économiques d'un territoire dans le but d'échanger de l'information, des matières premières et des déchets, et d'intensifier les mutualisations de services et d'infrastructures possibles entre entreprises voisines. Ces quatre types de collaboration sont représentés schématiquement dans la figure ci-dessous.Dans ce travail, la détection et la mise en oeuvre de symbioses industrielles sont abordées sous plusieurs angles. Les recherches réalisées concernent le développement de procédures de mise en oeuvre s'adressant aux collectivités publiques, aux institutions académiques et aux bureaux de conseil dans le domaine de l'environnement. Les objectifs des procédures sont de créer une dynamique de collaboration et de confiance entre les acteurs économiques et l'administration publique d'un territoire afin de détecter des symbioses industrielles potentielles. Ces procédures requièrent la gestion de grandes quantités d'informations relatives aux flux de matière et d'énergie.Un travail de terrain, réalisé sur les territoires du canton de Genève et de Lausanne Région et utilisé comme études de cas, a permis de mettre en évidence un grand nombre de symbioses industrielles qui existent déjà en Suisse romande. Plusieurs dizaines d'exemples ont été identifiés principalement dans lesdomaines de la gestion de l'eau, de l'énergie, des produits chimiques et des matériaux de construction. La législation suisse autoriserait cependant la concrétisation de nombreuses autres opportunités. Dans cette recherche, celles-ci sont évaluées techniquement, légalement, économiquement et environnementalement. La création d'un référentiel d'évaluation des opportunités permet de déterminer quelles sont les symbioses industrielles techniquement réalisables et pertinentes dans le contexte suisse et dans quels cas celles-ci représenteraient une réelle plus-value par rapport à l'utilisation actuelle de la ressource et aux filières existantes de collecte et de valorisation des déchets.Finalement, un logiciel, SymbioGIS, destiné à soutenir la détection et l'évaluation de symbioses industrielles potentielles a été développé. Il s'agit d'une interface web accessible pour de nombreux utilisateurs, couplée à une interface de systèmes d'information géographique. En plus de la détection de symbioses industrielles, plusieurs fonctionnalités sont proposées pour faciliter la prise en compte des flux de matière et d'énergie dans les problématiques liées à l'aménagement du territoire et au positionnement des activités économiques.En conclusion, cette recherche met en évidence la nécessité de rapprocher les institutions publiques en charge de la protection de l'environnement, de la promotion économique et de l'aménagement du territoire pour favoriser l'essor des symbioses industrielles comme stratégie pour la gestion des ressources matérielles et énergétiques. Elle propose des pistes pour intensifier les collaborations entre ces domaines et accélérer le partage des connaissances liées aux flux de matière et d'énergie et à leur cheminement au sein des activités économiques afin de rendre le système industriel existant en Suisse romande viable à long terme. Parallèlement, elle étudie les possibilités de transposer ces considérations et les procédures et outils développés dans le contexte économique et social de la région Asie-Pacifique, où se trouvent aujourd'hui de nombreuses activités de production.SummaryIndustrial symbioses: A new strategy for improving how economic activities use material and energy resourcesThis thesis focuses on one application of industrial ecology, industrial symbioses, as a strategy for improving how economic activities consume material and energy resources. Industrial symbioses seek to create new collaborations among economic players with the goal of exchanging information, raw materials, and waste directly among area businesses, and to step up the potential pooling of services and infrastructure among neighboring companies.The identification and implementation of industrial symbioses are studied from several angles. The research first examines the development of implementation procedures for government bodies, academic institutions, and environmental consulting services. The purpose of the procedures is to create a dynamic of collaboration and trust between the economic players and the public officials in a region in order to identify potential industrial symbioses. The procedures necessitate managing large amounts of information about material and energy flows.Fieldwork conducted in the canton of Geneva and the Lausanne region, and used as case studies for the research, highlights a great number of industrial symbioses that already exist in French-speaking Switzerland. Several dozen examples are identified, primarily in the areas of water management, energy, chemical products, and building materials; however, Swiss law would permit many others. The research evaluates these opportunities from a technical, legal, economic, and environmental standpoint. By developing an assessment framework it is possible to determine which industrial symbioses are technically feasible and pertinent in Switzerland, and under what circumstances they would represent real added value compared to the current use of the resource and to existing systems for collecting and reusing waste.Lastly, SymbioGIS software was developed to help identify and assess potential industrial symbioses. The program's Web-based interface can be accessed by multiple users and is coupled with an interface that provides geographic information. In addition to identifying industrial symbioses, several program functionalities make it easier to consider material and energy flows with regard to local development issues and siting economic activities.In conclusion, the research highlights the need to bring together public institutions charged with protecting the environment, promoting economic activity, and overseeing development in order to foster the expansion of industrial symbioses as a strategy for managing material and energy resources. It proposes solutions for stepping up collaboration among these players and accelerating the sharing of knowledge about material and energy flows and their paths within economic activities with the goal of making theexisting industrial system in French-speaking Switzerland viable long-term. Also examined were thepossibilities of transposing these considerations and the study's findings about Switzerland to the economic and social context of the Asia-Pacific region, where much production is now located.

Preliminary regional rockfall hazard mapping using LIDAR-based slope frequency distribution and CONEFALL modeling

A factor limiting preliminary rockfall hazard mapping at regional scale is often the lack of knowledge of potential source areas. Nowadays, high resolution topographic data (LiDAR) can account for realistic landscape details even at large scale. With such fine-scale morphological variability, quantitative geomorphometric analyses become a relevant approach for delineating potential rockfall instabilities. Using digital elevation model (DEM)-based ?slope families? concept over areas of similar lithology and cliffs and screes zones available from the 1:25,000 topographic map, a susceptibility rockfall hazard map was drawn up in the canton of Vaud, Switzerland, in order to provide a relevant hazard overview. Slope surfaces over morphometrically-defined thresholds angles were considered as rockfall source zones. 3D modelling (CONEFALL) was then applied on each of the estimated source zones in order to assess the maximum runout length. Comparison with known events and other rockfall hazard assessments are in good agreement, showing that it is possible to assess rockfall activities over large areas from DEM-based parameters and topographical elements.

Statistical evaluation of the influence of writing postures on on-line signatures. Study of the impact of time.

The aim of this study is to investigate the influence of unusual writing positions on a person's signature, in comparison to a standard writing position. Ten writers were asked to sign their signature six times, in each of four different writing positions, including the standard one. In order to take into consideration the effect of the day-to-day variation, this same process was repeated over 12 sessions, giving a total of 288 signatures per subject. The signatures were collected simultaneously in an off-line and on-line acquisition mode, using an interactive tablet and a ballpoint pen. Unidimensional variables (height to width ratio; time with or without in air displacement) and time-dependent variables (pressure; X and Y coordinates; altitude and azimuth angles) were extracted from each signature. For the unidimensional variables, the position effect was assessed through ANOVA and Dunnett contrast tests. Concerning the time-dependent variables, the signatures were compared by using dynamic time warping, and the position effect was evaluated through classification by linear discriminant analysis. Both of these variables provided similar results: no general tendency regarding the position factor could be highlighted. The influence of the position factor varies according to the subject as well as the variable studied. The impact of the session factor was shown to cover the impact that could be ascribed to the writing position factor. Indeed, the day-to-day variation has a greater effect than the position factor on the studied signature variables. The results of this study suggest guidelines for best practice in the area of signature comparisons and demonstrate the importance of a signature collection procedure covering an adequate number of sampling sessions, with a sufficient number of samples per session.

Eina per a la visualització de molècules

Aquest TFC consisteix a construir una eina que permet visualitzar molècules en aquest format de visualització. L'eina haurà de permetre navegar al voltant de la molècula i emprar tècniques de selecció que permetin identificar àtoms, calcular distàncies i angles de torsió. A més, s'haurà de poder definir un eix i sobre aquest eix generar una rotació i gravar-la en una pel·lícula (en el format que sigui més senzill).

Diseño de una herramienta para la visualización de moleculas

L'objectiu d'aquest TFC consisteix a desenvolupar i implementar l'eina de visualització molecular opengl: HVM. Aquesta aplicació, que permet la visualització i la inspecció de molècules, és de gran utilitat en àrees com la química, la farmàcia, la docència, etc., i admet definicions de molècules mitjançant un fitxer d'entrada (una variació simplificada del format XMOL XYZ), construint-ne el model, cosa que afavoreix que s'hi pugui navegar, com també la selecció i la identificació dels seus elements i el càlcul de distàncies i angles de torsió entre ells. A més, permet la definició d'un eix sobre el qual es pot generar una rotació del model i gravar una seqüència de sortida.

Improving binding affinity and stability of peptide ligands by substituting glycines with D-amino acids.

Improving the binding affinity and/or stability of peptide ligands often requires testing of large numbers of variants to identify beneficial mutations. Herein we propose a type of mutation that promises a high success rate. In a bicyclic peptide inhibitor of the cancer-related protease urokinase-type plasminogen activator (uPA), we observed a glycine residue that has a positive ϕ dihedral angle when bound to the target. We hypothesized that replacing it with a D-amino acid, which favors positive ϕ angles, could enhance the binding affinity and/or proteolytic resistance. Mutation of this specific glycine to D-serine in the bicyclic peptide indeed improved inhibitory activity (1.75-fold) and stability (fourfold). X-ray-structure analysis of the inhibitors in complex with uPA showed that the peptide backbone conformation was conserved. Analysis of known cyclic peptide ligands showed that glycine is one of the most frequent amino acids, and that glycines with positive ϕ angles are found in many protein-bound peptides. These results suggest that the glycine-to-D-amino acid mutagenesis strategy could be broadly applied.

Ambulatory gait analysis results after total knee arthroplasty : arguments for mobile or fixed bearing?

Background: Mobile-bearing knee replacements have some theoretical advantages over fixed-bearing devices. However, very few randomized controlled clinical trials have been published to date, and studies showed little clinical and subjective advantages for the mobile-bearing using traditional systems of scoring. The choice of the ideal outcome measure to assess total joint replacement remains a complex issue. However, gait analysis provides objective and quantifying evidences of treatment evaluation. Significant methodological advances are currently made in gait analysis laboratories and ambulatory gait devices are now available. The goal of this study was to provide gait parameters as a new objective method to assess total knee arthroplasty outcome between patients with fixed- and mobile-bearing, using an ambulatory device with minimal sensor configuration. Methods: This randomized controlled double-blind study included to date 31 patients: the gait signatures of 12 patients with mobile-bearing were compared to the gait signatures of 19 patients with fixed-bearing pre-operatively and post-operatively at 6 weeks, 3 months and 6 months. Each participant was asked to perform two walking trials of 30m long at his/her preferred speed and to complete a EQ-5D questionnaire, a WOMAC and Knee Society Score (KSS). Lower limbs rotations were measured by four miniature angular rate sensors mounted respectively, on each shank and thigh. Results: Better relative differences between pre-operative and post-operative 3 months and 6 months KSS (122% vs 34% at 3 months, 138% vs 36% at 6 months) and KSS function (154% vs 8% at 3 months, 183% vs 42% at 6 months) scores were observed for the fixed-bearing compared to the mobile-bearing. The same better improvements for fixed-bearing were also found with the range of knee angles (Affected side: 31% vs -5% at 3 months, 47% vs 5% at 6 months), (Unaffected side: 16% vs 5% at 3 months, 15% vs 6% at 6 months) and peak swing speeds of shank (Affected side: 18% vs -2% at 3 months, 30% vs 4% at 6 months), (Unaffected side: 8% vs -3% at 3 months, 7% vs 4% at 6 months). Conclusions: A new method for a portable system for gait analysis has been developed with very encouraging results regarding the objective outcome of total knee arthroplasty using mobile- and fixed-bearings.

Circulating natural killer and γδ T cells decrease soon after infection of rhesus macaques with lymphocytic choriomeningitis virus

Rhesus macaques infected with the WE strain of lymphocytic choriomeningitis virus (LCMV-WE) serve as a model for human infection with Lassa fever virus. To identify the earliest events of acute infection, rhesus macaques were monitored immediately after lethal infection for changes in peripheral blood mononuclear cells (PBMCs). Changes in CD3, CD4, CD8 and CD20 subsets did not vary outside the normal fluctuations of these blood cell populations; however, natural killer (NK) and γδ T cells increased slightly on day 1 and then decreased significantly after two days. The NK subsets responsible for the decrease were primarily CD3-CD8+ or CD3-CD16+ and not the NKT (primarily CD3+CD56+) subset. Macaques infected with a non-virulent arenavirus, LCMV-Armstrong, showed a similar drop in circulating NK and γδ T cells, indicating that this is not a pathogenic event. V³9 T cells, representing the majority of circulating γδ T cells in rhesus macaques, displayed significant apoptosis when incubated with LCMV in cell culture; however, the low amount of cell death for virus-co-cultured NK cells was insufficient to account for the observed disappearance of this subset. Our observations in primates are similar to those seen in LCMV-infected mice, where decreased circulating NK cells were attributed to margination and cell death. Thus, the disappearance of these cells during acute hemorrhagic fever in rhesus macaques may be a cytokine-induced lymphopenia common to many virus infections.

Evaluation of a mixed approach combining stationary and wearable systems to monitor gait over long distance.

Thanks to decades of research, gait analysis has become an efficient tool. However, mainly due to the price of the motion capture systems, standard gait laboratories have the capability to measure only a few consecutive steps of ground walking. Recently, wearable systems were proposed to measure human motion without volume limitation. Although accurate, these systems are incompatible with most of existing calibration procedures and several years of research will be necessary for their validation. A new approach consisting of using a stationary system with a small capture volume for the calibration procedure and then to measure gait using a wearable system could be very advantageous. It could benefit from the knowledge related to stationary systems, allow long distance monitoring and provide new descriptive parameters. The aim of this study was to demonstrate the potential of this approach. Thus, a combined system was proposed to measure the 3D lower body joints angles and segmental angular velocities. It was then assessed in terms of reliability towards the calibration procedure, repeatability and concurrent validity. The dispersion of the joint angles across calibrations was comparable to those of stationary systems and good reliability was obtained for the angular velocities. The repeatability results confirmed that mean cycle kinematics of long distance walks could be used for subjects' comparison and pointed out an interest for the variability between cycles. Finally, kinematics differences were observed between participants with different ankle conditions. In conclusion, this study demonstrated the potential of a mixed approach for human movement analysis.

Response to comment on "the geometric structure of the brain fiber pathways".

In response to Catani et al., we show that corticospinal pathways adhere via sharp turns to two local grid orientations; that our studies have three times the diffusion resolution of those compared; and that the noted technical concerns, including crossing angles, do not challenge the evidence of mathematically specific geometric structure. Thus, the geometric thesis gives the best account of the available evidence.

Disseny d'un banc de proves per a poder mesurar les pèrdues de fregament i rodadura [sic] de pneumàtics

Dintre del projecte del cotxe de baix consum “Àliga”, vehicle experimental que participa en la “Eco-Shell Marathon”, una competició internacional que es realitza anualment, el projecte tracta del disseny d’un banc de proves per a poder mesurar les pèrdues de fregament dels pneumàtics provant diferents pressions, càrregues suportades, angles de la direcció, tipus de pneumàtics i diversos components del sistema de direcció

Comparison of three commercially available radio frequency coils for human brain imaging at 3 Tesla.

OBJECTIVE: To evaluate a transverse electromagnetic (TEM), a circularly polarized (CP) (birdcage), and a 12-channel phased array head coil at the clinical field strength of B0 = 3T in terms of signal-to-noise ratio (SNR), signal homogeneity, and maps of the effective flip angle alpha. MATERIALS AND METHODS: SNR measurements were performed on low flip angle gradient echo images. In addition, flip angle maps were generated for alpha(nominal) = 30 degrees using the double angle method. These evaluation steps were performed on phantom and human brain data acquired with each coil. Moreover, the signal intensity variation was computed for phantom data using five different regions of interest. RESULTS: In terms of SNR, the TEM coil performs slightly better than the CP coil, but is second to the smaller 12-channel coil for human data. As expected, both the TEM and the CP coils show superior image intensity homogeneity than the 12-channel coil, and achieve larger mean effective flip angles than the combination of body and 12-channel coil with reduced radio frequency power deposition. CONCLUSION: At 3T the benefits of TEM coil design over conventional lumped element(s) coil design start to emerge, though the phased array coil retains an advantage with respect to SNR performance.