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La rupture du ligament croisé antérieur chez le gymnaste de haut niveau
No full textAIX-MARSEILLE2-BU Pharmacie (130552105) / SudocSudocFranceF
Investigating the effects of nutrient concentration and light intensity on benthic biofilm development and phytoplankton growth in UK rivers
No full textPhosphorus is often considered the limiting nutrient in rivers, and reducing concentrations has long been a key policy focus. However, experience has shown that many phosphorus mitigation schemes fail to achieve any improvements in ecological status. The primary aim of this thesis is to identify target phosphorus concentrations that need to be attained to improve river ecology. In-stream flume mesocosms were deployed on three UK rivers of varying levels of nutrient enrichment. Phosphorus concentrations were simultaneously increased and decreased (by iron-dosing) to provide a concentration gradient over which periphyton accrual was examined. This identified whether rivers were phosphorus limited, and allowed a phosphorus-limiting threshold to be quantified. The effects of nitrogen, and combined phosphorus and nitrogen addition were also examined. The River Lamboum study simultaneously manipulated light intensity and nutrient concentrations, demonstrating shading to have benefits in improving periphyton quality as a food resource and in reducing periphyton accrual. The near-pristine River Rede showed that increase in river phosphorus concentration had no effect on periphyton growth rate, but that there was a 3.5-fold increase in growth rate when phosphorus and nitrogen were added simultaneously, demonstrating the presence of sequential nutrient co-limitation. By repeating a 2005 study on the River Frome, the 2012 study proved that phosphorus-limiting thresholds change in response to changing river nutrient concentrations. Examination of changes in community structure by the trophic diatom index and flow cytometry provide evidence for a lower ecological threshold in rivers of ca. 30 Ilg rI. A fast repetition rate fluorometer was used to assess phytoplankton stress across the Thames catchment throughout an algal bloom and data was examined alongside water quality data. Bloom development and collapse was primarily controlled by residence time and, secondarily, phosphorus concentration. This thesis has challenged traditional beliefs that phosphorus is the limiting nutrient in freshwater ecosystems and has provided insights on how to best meet the requirements of the Water Framework Directive and improve ecological status.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Diasporic connectivity and patriarchal formations in the sex trafficking of women
No full textThis thesis explores diasporic connectivities and formations of patriarchy in the cross-border sex trafficking of women in the United Kingdom. The function of heteronormativity in the trafficking process is also a key concern. This is a multi-methods study, drawing on interviews with experts in the field of trafficking, and on data extracted from completed Crown Prosecution Service trafficking case files. Interviews with national and international experts were undertaken to explore the extent of the knowledge base on crime groups engaged in the sex trafficking of women into and within the UK by reference to their structure, composition, modus operandi, and to the role of diasporas in the trafficking process. Additionally, through data extracted from Crown Prosecution Service trafficking files, defendants are profiled and groups are allocated to models in a typology hypothesizing four possible intersections between traffickers and their respective diasporas in the UK. The role of diasporas and the function of heteronormativity are similarly explored through the data during each phase of recruitment, movement and exploitation, and with particular focus on women as traffickers. The thesis shows the methods of recruitment employed in source countries to ensure the supply of women, and the forms of control exercised by traffickers in the UK. In examining the business of exploitation, it further shows how the commodification of women is central to the hegemonic masculinity project.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
An investigation of vitamin D status in systemic lupus erythematosus - its relationship with disease activity, bone mineral density and quality of life
No full textVitamin D has the potential to modulate the immune system resulting in an inflammatory response which could lead to improved clinical outcomes for individuals diagnosed with systemic lupus erythematosus (SLE). The overall aim of this research was to investigate vitamin D status in SLE patients residing in Northern Ireland, to determine whether there was a relationship with disease activity, bone mineral density (BMD) and quality of life (QoL). To achieve this we undertook a pilot study in SLE patients (n=19) and age-and-sex matched control participants (n= 19), to investigate the vitamin D status of SLE patients. This was followed by a larger observational study to examine vitamin D status in SLE patients during winter months (November-March) and again in the summer months (June-July). A total of 52 SLE patients were recruited, of which, 50 completed the study. Serum 25-hydroxyvitamin D (25(OH)D) was assessed by liquid chromatography mass spectrometry and disease activity and damage were scored using Systemic Lupus Activity Measure (SLAM), British Isles Lupus Assessment Group (BILAG), Safety of Estrogen in Lupus Erythematosus National Assessment Trial Systemic Lupus Erythematosus Disease Activity Index (SELENA SLEDAI) and Systemic Lupus International Collaborative Clinics/American College of Rheumatology (SLICC/ ACR). BMD was measured by Dual Energy X-ray absorptiometry, fatigue was assessed by the fatigue severity score and percieved QoL was assessed using the 36-item short form health survey. BMD was measured during the winter assessment of the observational study and at both time points, associations between vitamin D, disease activity, fatigue and QoL were examined by means of correlation and regression analysis. Vitamin D inadequacy was prevalent in this cohort of SLE patients residing in Northern Ireland, although no significant difference in vitamin D status was observed between winter and summer (P=0.439). Some 98% of SLE patients presented with serum 25(OH)D concentration < 75 nmol/L at both timepoints and vitamin D concentration was inversely associated with BILAG during winter. Fatigue was present in 98% of the cohort during both time points and patients with fatigue had significantly lower vitamin D status compared to those without fatigue (P=0.030). Furthermore, BILAG was a useful predictor of future fatigue in this cohort. Osteoporosis and osteopenia were identified in 8% and 45% of the SLE patients respectively, none of whom were prescribed calcium/vitamin D supplements. The social functioning (P=0.023) and mental component scores (P=0.049) of the 36-item short form questionnaire were significantly decreased during the summer. This cohort of SLE patients appeared to have much lower QoL throughout the year than that of SLE patients reported in other studies and both fatigue and disease activity were shown to be associated with QoL. The findings of this research could impact on patient care, given the high prevalence of vitamin D inadequacy and its relationship with disease activity and fatigue. These novel results provide some evidence of a potential relationship between vitamin D and disease activity. If proven, increased vitamin D status could improve clinical outcomes such as fatigue and disease activity thereby indirectly improving QoL. Future research involving vitamin D supplementation in SLE patients to optimise status would strengthen the evidence for beneficial effects of vitamin D in SLE.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Specialist nursing for people with multiple sclerosis affected by fatigue : a case study inquiry
No full textAim The aim of the study was to explore how specialist nursing affected the experience of fatigue for people with multiple sclerosis. Methodology This mixed method case study is a single embedded revelatory approach designed to investigate specialist nurse interaction with patients with multiple sclerosis who experience fatigue. The convenience sample of one nurse and two patients constitutes the case. The case is bounded by purposively sampling data which were collected by the use of: interview, observation, reflective diaries. Assessment tools were also used for fatigue, depression, disability and the impact of MS, and actigraphy recording of patient activity. Participants completed key measurements and interview at three monthly intervals during the one year study period. Other data collection was organised to reflect the frequency of nurse patient consultations. The critical social theory of Jurgen Habermas and specifically his theories of moral consciousness and communicative action were used to aid interpretation of data. Conclusions Actigraphy demonstrated that overall level of physical activity for both patients was similar despite differences in fatigue experience. Differences occurred in how patients: (i) Chose to utilise the level of physical activity available to them; (ii) The sense of meaning that they constructed around their experience of fatigue and (iii) The adoption of self management techniques.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Error resilient scalable video coding
No full textVideo compression is necessary for effective coding of video data so that the data can be stored or transmitted more efficiently. In video compression, the more redundant data are discarded, the higher compression ratios will be achievable. This causes the contents of a compressed bitstream to be highly dependent on each other. In video communications, the compressed bitstream is ,subject to losses and errors due to the nature of the transmission medium. Since the contents of the compressed bitstream are highly dependent on each other, when a loss or an error occurs this leads to propagation of the error, which causes deterioration of the decoded video quality. Error resilience plays an important role / in decreasing the quality degradation caused by losses arid errors. Error resilience methods can either take place in the encoder side as a coding technique which decreases the effects of errors on the coded bitstream or in the decoder side as a technique which conceals the detected errors or losses. Error concealment which takes place in decoder side and redundant slice coding which takes place in encoder side are investigated throughout the thesis. The first part of the thesis investigates efficient error concealment techniques for Scalable Video Coding (SVC). These include the utilisation of higher Temporal Level picture motion information and the utilisation of "Bridge Pictures" which will be described in later chapters, for error concealment. The second part of the thesis investigates redundant slice coding for SVc. Single Block per Macroblock and Zero Residual redundant slice coding schemes are proposed and tested in this part of the thesis. In addition to these, an adaptive redundant slice allocation scheme is also proposed and tested. The last part of the thesis investigates error resilient coding techniques for multi-view 3D video. Multi-view 3D video compression is achieved using the SVC CoDec by coding one of the views as the Base Layer and the other views as the Enhancement Layers utilising the adaptive inter-layer prediction mechanism of the SVc.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
A Content-Centric Networking Node for a Realistic Efficient Implementation and Deployment
No full textThe current IP based Internet architecture was designed in 70s. The development of new technologies and the evolution of Internet usages make the limitations of this design more visible, especially for the content delivery services. Facing this shortcoming, Van Jacobson and his PARC team proposed Content-Centric Network (CCN) in 2009. The CCN aims to build a content-oriented network, which means the entire networking architecture and all the networking activities are based on the content (content names in particular). The CCN proposal integrates many features such as on-path caching, security, multicast, and native mobility management. This novel proposal has many benefits but it brings also a lot of challenges for current hardware technologies. The transition from IP addresses to content names requires a large memory space to store the content names. However today's fast memory chip cannot meet this requirement. In this thesis I firstly focus on the PIT (Pending Interest Table) element in CCN routers. I propose a distributed PIT system based on the Bloom filter structure to reduce memory requirements and further improve routing performances. The principle of my proposal is that each CCN face manages its own PIT table instead of using a global table read/write lock for a centralized table. This distributed design resolves the information retrieval problem, which is a native shortcoming of Bloom filters. Thus treatment and routing speeds are improved. Thereafter I concentrate on the FIB (Forwarding Information Base) element. In the original CCN design, the FIB is filled by flooding content advertisement. With respect to the huge number of potential content names, this method not only explodes the capacity of FIB tables, but also introduces a high networking traffic. I propose a content-aware CCN forwarding system, which includes a content advertisement publish protocol, a FIB filling algorithm and a downstream forwarding element. In short, the content publish protocol requires that each advertisement is forwarded only towards certain nodes while the downstream forwarding element is a table that is in charge of discovering the other potential content sources. In the third contribution I propose an interface for interconnecting the CCN networking structure with the CDN services. The CDN service has so far been the way to address the content delivery issues of Internet. The key point of interconnecting CCN with CDN service is how to resolve the CDN repository miss-hit problem. The original CCN proposal does not enable efficient interconnection between CDN and CCN. I propose a system, which includes a CDN repository forwarding element and a CDN repository miss awareness mechanism. The former element is in charge of sending the related Interests towards the CDN repositories while the latter one aims to detect the CDN content miss and recover this lost..L'architecture de l'Internet, basée sur IP, a été crée dans les années 70. Les nouvelles technologies et l'évolution des usages de l'Internet démontrent les limites de ce modèle. Pour remédier à ces limites, Van Jacobson et son équipe ont proposé Content- Centric Networking (CCN). CCN a pour objectif de construire un réseau orienté contenus, où l'architecture et toutes les activités de réseau sont basés sur le contenu. CCN intègre de nombreuses fonctionnalités dans les réseaux. Cette proposition a plusieurs avantages mais elle apporte également des challenges pour les technologies matérielles actuelles. La transition des adresses IP vers les noms de contenu nécessite un grand espace de mémoire. Mais les mémoires rapides d'aujourd'hui ne peuvent pas répondre à ce besoin. Dans cette thèse, je me suis concentré d'abord sur l'élément PIT (Pending Interest Table) des noeuds CCN. Je propose un système de PIT distribué, basé sur les filtres de Bloom, pour réduire les besoins de mémoire et améliorer les performances de routage. Le principe est que chaque face CCN gère sa propre table PIT au lieu d'utiliser une table centralisée. Cette conception distribuée résout le problème de récupération des informations, qui est une contrainte native des filtres de Bloom. Ainsi la vitesse de traitement et de routage sont améliorées. Par la suite, je me suis focalisé sur l'élément FIB (Forwarding Information Base). Dans la conception de CCN, la table FIB est remplie par les publications de contenus diffusées. En ce qui concerne le grand nombre de noms de contenu, cette méthode non seulement génère une taille de FIB démesurée, mais introduit également une charge de trafic réseau important. Je propose un système de forwarding dynamique, basé sur les contenus, qui contient un protocole de publications de contenus, un algorithme de remplissage de la FIB, et un élément de transmission vers l'aval. Le protocole de publication demande que chaque annonce soit envoyée seulement vers certains noeuds. L'élément de transmission en aval s'occupe de trouver les autres sources potentielles de contenu. Dans la troisième contribution, j'ai proposé une interface pour connecter le réseau CCN avec les services CDN. Le point clé de l'interconnexion de CCN avec CDN concerne la gestion de miss-hit dans les serveurs CDN. La proposition originale CCN ne permet pas une interconnexion efficace entre CDN et CCN. J'ai proposé un système, qui comprend un élément en charge du transfert des requêtes vers des serveurs CDN et un mécanisme de redirection, pour des requêtes qui ont des miss-hit, vers des serveurs originaux. Pour résumer, cette thèse contient trois contributions, qui se concentrent individuellement sur différents composants d'un noeud CCN. Chacune de ces propositions améliore les performances des noeuds CCN. Ils peuvent être combinés pour créer un noeud CCN complet, plus efficace et réaliste..CESSON SEVIGNE-Télécom Breta (350512301) / SudocSudocFranceF
Facteurs prédictifs du chimérisme après greffe non apparentée de cellules souches de sang placentaire chez l'enfant
No full textL'objectif de ce travail était de décrire la probabilité de survenue d'un chimérisme complet de type donneur (cDC, >99,9% donneur) après une greffe non apparentée de cellules souches de sang placentaire chez l'enfant, d'en identifier les facteurs prédictifs ainsi que son impact sur le devenir post greffe. 94 enfant greffes par une unité de sang placentaire après préparation myeloablative, ont été inclus dans notre étude. Le chimérisme, quantifié sur sang périphérique selon la technique TAQMAN (sensibilité de 0,1%) a été recueilli de manière séquentielle une période de 3 ans post greffe. L'incidence cumulative de survenue d'un chimérisme >99,9% donneur à 1 an est de 61,8%. Lors de l'analyste multivariée, 3 facteurs prédictifs ont été mis en évidence: le caractère malin de la pathologie initiale (p=0,03) l'âge avec comme facteur péjoratif un âge à la greffe inférieur à 2,16 ans (correspondant ua 1er quartile de notre étude, p=2,9.10-3) et la compatibilité HLA entre donneur et receveur (p=8,7.10-4), qui lorsqu'elle est moindre est associée à une probabilité plus importante d'apparition d'un chimérisme complet au cours du temps. Bien que la quantité cellulaire injectée ait un fort impact sur la reconstitution hématologique, elle ne semble pas influencer le chimérisme après greffe. Concernant le devenir post greffe, l'apparition d'un chimérisme complet précoce (c'est-à-dire un chimérisme >99,9% donneur dans le premier mois qui suit la greffe) apparaît prédictif de la prise de greffe (p=<0.10-3) mais aussi de la survenue de la maladie du greffon contre l'hôte (GvHD pour Graft versus Host Disease) à la fois aiguë et chronique. Aucune GvHD aiguë sévère ou chronique n'a été retrouvée chez les patients n'ayant jamais développé de chimérisme complet ce qui suggère qu'une hématopoïèse résiduelle même minime de type receveur protégerait de la survenue de GvHD après greffe de sang placentaireAIX-MARSEILLE2-BU Méd/Odontol. (130552103) / SudocSudocFranceF
Analyse descriptive des arrêts cardio-respiratoires survenus dans le Bas-Rhin en 2009
No full textSTRASBOURG-Medecine (674822101) / SudocSudocFranceF
Etude des corrélations entre les marqueurs de l'hôte et les marqueurs virologiques du virus de l'hépatite B en fonction de la réponse aux traitements par interféron
No full textAvec 350 millions de porteurs chroniques dans le monde, le virus de l'hépatite B (VHB) est un problème majeur de santé publique. L'évolution de l'infection peut conduire au développement d'une cirrhose et/ou d'un carcinome hépatocellulaire. L'ensemble de mes travaux de thèse a pour but d'étudier la corrélation entre la réponse au traitement, les marqueurs de l'hôte et ceux du virus chez des patients atteints d'hépatite chronique B (CHB). Dans un premier temps, nous avons étudié l'impact du polymorphisme rs12979860 de l'IFNL3 sur la réponse à l'IFN standard chez 97 patients atteints de CHB, AgHBe-positif. Aucune association n'a été observée entre le génotype de l'IFNL3 (rs12979860) et la réponse au traitement par IFN. Dans un deuxième temps, mes travaux ont porté sur la variabilité génomique de l'AgHBs chez les patients CHB, traités par IFN-pégylé plus Ténofovir .12, 5% des patients traités (n=40) ont une perte de l'Ag HBs. L'analyse des quasi-espèces virales a montré qu'il y avait une variabilité génomique dans le gène S chez les non-répondeurs. Ces mutations sont localisées au niveau de la RHM et plus spécifiquement dans le déterminant a . L'analyse, in vitro, a montré que la présence des mutations dans le déterminant a est associée à une plus faible production de l'AgHBs mais à une réplication virale équivalente au virus sauvage. En conclusion, mes travaux de thèses ont permis de mieux comprendre le rôle de l'IFNL3 et de l'AgHBs, dans les mécanismes de réponse au traitement. Ces recherches ont pour but d'optimiser l'utilisation de ces marqueurs, dans la pratique, clinique afin d'améliorer la prise en charge des patients CHB.PARIS7-Bibliothèque centrale (751132105) / SudocSudocFranceF