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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

GSTR: Secure Multi-Hop Message Dissemination in Connected Vehicles Using Social Trust Model

Paranjothi, Anirudh, Khan, Mohammad S., Zeadally, Sherali, Pawar, Ajinkya, Hicks, David 01 September 2019 (has links)
The emergence of connected vehicles paradigm has made secure communication a key concern amongst the connected vehicles. Communication between the vehicles and Road Side Units (RSUs) is critical to disseminate message among the vehicles. We focus on secure message transmission in connected vehicles using multi-hop social networks environment to deliver the message with varying trustworthiness. We proposed a Geographic Social Trust Routing (GSTR) approach; messages are propagated using multiple hops and by considering the various available users in the vehicular network. GSTR is proposed in an application perspective with an assumption that the users are socially connected. The users are selected based on trustworthiness as defined by social connectivity. The route to send a message is calculated based on the highest trust level of each node by using the node's social network connections along the path in the network. GSTR determines the shortest route using the trusted nodes along the route for message dissemination. GSTR is made delay tolerant by introducing message storage in the cloud if a trustworthy node is unavailable to deliver the message. We compared the proposed approach with Geographic and Traffic Load based Routing (GTLR), Greedy Perimeter Stateless Routing (GPSR), Trust-based GPSR (T-GPSR). The performance results obtained show that GSTR ensures efficient resource utilization, lower packet losses at high vehicle densities.
72

Spores of C. difficile in hospital air

Snelling, Anna M., Beggs, Clive B., Kerr, Kevin G., Shepherd, Simon J. January 2010 (has links)
no
73

Reason is King and Science is his Crown: A Study of French Science-Fiction for the Dissemination of Philosophical Thought

Gandy, Lauren A 01 January 2016 (has links)
The thesis seeks to explore the didactic application of French science-fiction during the seventeenth and eighteenth centuries for the portrayal and dissemination of their respective philosophical theories. Studying science-fiction novels during these centuries will allow a comparison of seventeenth and eighteenth-century dissemination methods, to determine if the foundational seventeenth-century methods were retained or modified to more accurately represent the change in philosophical attitudes. Exploration of this topic will contribute to a greater understanding of French Enlightenment theory, analysis of relatively unstudied novels in the science-fiction genre, and a novel approach to “proto” science-fiction literature by connecting the previously separate genres of science-fiction and philosophy during the Enlightenment. The trends within the seventeenth century show dominant authoritative representations through analogical examples, authoritative ideological figures, and an emphasis on logically sustained arguments. The eighteenth-century trends focus on logical passionate attitudes, burlesque scenarios, and authoritative actions to exemplify the Enlightenment ideologies. Therefore, these five analyzed œuvres show conservation of didactic and authoritative dissemination methods during this philosophically evolutionary time period.
74

Studies in Shiga toxin-producing Escherichia coli O157:H7: determination of factors contributing to the dissemination of Escherichia coli O157:H7 among dairy farms

Wetzel, Amy Noel 02 December 2005 (has links)
No description available.
75

Dissemination of exposure-based treatment for anxiety: Experiential training for community therapists

Frank, Hannah, 0000-0003-2396-4585 January 2020 (has links)
Background: Although exposure is considered an active ingredient in evidence-based treatments (EBTs) for anxiety, it is infrequently used in routine clinical care settings. Therapist-level barriers to the use of exposure include inadequate training and negative beliefs about exposure. Prior efforts to train therapists in exposure therapy have resulted in knowledge but not behavior change. This study employed a novel training strategy, experiential learning, designed to improve the translation of knowledge into clinical practice. This study’s aims were to assess the feasibility and acceptability of experiential training (ET), as well as to conduct exploratory inferential analyses examining knowledge, attitudes, and use of exposure following training. Methods: Participants included 28 therapists working in routine clinical care settings. They were randomized to one of two conditions to learn about exposure therapy: training as usual (TAU) or ET (i.e., undergoing a one-session treatment for fear of spiders). Both workshops lasted one day, and participants were expected to attend weekly consultation calls for three months after training. Qualitative interviews were conducted at the end of the consultation call period. Results: The ET was feasible and acceptable to participants. Qualitative interviews suggested that participants, including those who were fearful of spiders, had a positive response to the training and found it to be useful. Quantitative analyses found that there was a significantly greater increase in the number of exposures used following ET than TAU at 1-month follow up. Both conditions demonstrated significant increases in knowledge, attitudes toward exposures, and self-efficacy following the training. Conclusions: The findings suggest that, consistent with previous research, a one-day training resulted in significant improvements in therapist-level factors that may affect the use of exposure. In addition, there is initial evidence that ET resulted in greater use of exposure after training, which applied more broadly, could increase the number of clients receiving an EBT for anxiety. The results provide promising evidence for the utility and acceptability of ET as a strategy to increase the use of EBTs in clinical practice. / Psychology
76

A randomized controlled trial of training in cognitive-behavioral therapy for youth anxiety

Beidas, Rinad January 2011 (has links)
Establishing evidence-based training for therapists is of paramount importance for effective dissemination of evidence-based interventions. Using cognitive-behavioral therapy (CBT) for child anxiety, this study compared three therapist training conditions: (1) routine training: a workshop that covered a specific manual, (2) computer training: computer-based training via an interactive DVD, and (3) augmented training: a workshop that included a focus on core CBT competencies and active learning with behavioral rehearsal. Training success was operationalized as: (1) adherence to CBT for child anxiety, (2) therapeutic skillfulness, (3) a knowledge test, (4) and training satisfaction. The study also investigated the degree to which consultation following training impacted therapist outcomes. Participants (115 therapists) were randomly assigned to training condition and, following training, were invited to participate in weekly consultation. The results indicate that all three training conditions were effective in improving therapist adherence, skill, and knowledge. Participants were most satisfied with the in-person conditions. With regard to consultation, the number of consultation hours attended significantly predicted therapist training outcomes. This finding underscores the importance of consultation when training therapists. / Psychology
77

The Effect of Polysialic Acid Expression on Glioma Cell Nano-mechanics

Grant, Colin A., Twigg, Peter C., Saeed, Rida F., Lawson, G., Falconer, Robert A., Shnyder, Steven 01 March 2016 (has links)
Yes / Polysialic acid (PolySia) is an important carbohydrate bio-polymer that is commonly over-expressed on tumours of neuroendocrine origin and plays a key role in tumour progression. PolySia exclusively decorates the neural cell adhesion molecule (NCAM) on tumour cell membranes, modulating cell-cell interactions, motility and invasion. In this preliminary study, we examine the nano-mechanical properties of isogenic C6 rat glioma cells - transfected cells engineered to express the enzyme polysialyltransferase ST8SiaII, which synthesises polySia (C6-STX cells) and wild type cells (C6-WT). We demonstrate that polySia expression leads to reduced elastic and adhesive properties but also more visco-elastic compared to non-expressing wild type cells. Whilst differences in cell elasticity between healthy and cancer cells is regularly assigned to changes in the cytoskeleton, we show that in this model system the change in properties at the nano-level is due to the polySia on the transfected cell membrane surface.
78

Cultivating a Healthy School Environment: Evaluation of a Virginia School Nutrition Training Program

Nelson, Rachel A. 18 May 2020 (has links)
The Reach, Effectiveness, Adoption, Implementation, Maintenance (RE-AIM) framework was used to evaluate the impact of the Virginia Department of Education's (VDOE) implementation of the USDA's Team Nutrition training program on Virginia elementary schools from 2017-2020. The VDOE provided training for school nutrition directors (SNDs) at workshops in June 2018 and September 2019 and continued technical assistance to help SNDs improve the school food environment within their divisions. SNDs' perceived support, self-efficacy, and intention to implement changes to the school food environment was measured through pre- and post-training surveys and quarterly check-ins. Implementation was measured using lunchroom environment observations and strategic plans created at the workshops. SNDs representing 83.9% of Virginia elementary students (512,953 students) in 111 divisions attended at least one of the workshops. Within effectiveness, perceived support from cafeteria staff was highest among all stakeholders for both the 2018 and 2019 trainings, though it significantly decreased from before to after the training for both workshops. Average perceived support did not significantly change over time. Self-efficacy was significantly higher following the 2018 training workshop only. The intervention was adopted by 84% of divisions and both intention to implement and actual implementation were highest for strategies related to Farm to School, a VDOE priority. Effectiveness and implementation are expected to improve as it takes up to years for changes to occur in schools. Despite RE-AIM not being part of the initial evaluation plan, 62% of indicators were assessed. With some adaptations to improve effectiveness, the intervention should continue and be expanded. / Master of Science / Interventions to improve the dietary habits of children are often conducted in schools, as most children attend school and children consume up to two meals while at school. USDA's Team Nutrition initiative trains school nutrition staff to serve healthy school meals and provides materials to implement nutrition education for students. The Virginia Department of Education implemented the Team Nutrition program statewide through two training workshops for school nutrition directors (SNDs), June 2018 and September 2019, and technical assistance between the trainings. This study examined the process of implementing the intervention, as well as the outcomes. Overall, 84% of Virginia elementary students were represented by SNDs at the training workshops. SNDs were most likely to intend to implement and implement changes in their divisions related to Farm to School programs and least likely change their culinary skills trainings for staff. It can take up to two years after a training for changes to be implemented in schools, therefore it may be too early to know the full effect of the training. The results showed that the intervention was widely adopted, with 84.1% of divisions in Virginia attending at least one of the training workshops. Although participation was high in-person, less SNDs participated in the intervention activities outside of the trainings. Overall, the intervention was successful in reaching many students and had a small positive effect. With some adaptations to improve the effectiveness, the intervention should continue to be implemented and expanded to the rest of the state.
79

An Extensible Information Dissemination Scheme over the Optimized Link State Routing Protocol for Mobile Ad Hoc Networks

Mehrjoo, Kaveh 10 October 2007 (has links)
A mobile ad hoc network (MANET) is formed by a collection of self-organizing nodes. Such networks are being deployed in a variety of environments, for example to provide mission-critical services in times of crises. Nodes participating in a MANET tend to have limited energy and computing resources and depend on various network-based resources to operate as a cohesive system. The same features such as dynamic and adaptive network topologies that make MANETs powerful also make the discovery and operation of network services a challenge. This thesis presents the design and implementation of an extensible information dissemination scheme that is integrated with the Optimized Link State Routing (OLSR) protocol to address the challenges of service discovery in mobile ad hoc networks. The thesis presents a detailed design of the information dissemination scheme based on the Naval Research Laboratory's (NRL) ProtoLib network protocol programming framework. In the proposed scheme, a solution that separates the routing process from the NRL OLSR routing protocol was designed, thus making OLSR a topology discovery protocol. This can further facilitate the implementation of various routing algorithms based on other metrics, such as the signal-to-noise ratio (SNR) of wireless links or the nodes' level of cooperation, when forwarding messages in the network. Additionally, a reusable event-driven programming interface to the NRL OLSR routing protocol was designed and implemented in this research. Events are triggered based on changes in the network topology. This programming interface can be used by other management and monitoring clients on the network for receiving real-time updates about link and topology changes as seen by OLSR. A priority message delivery scheme was developed that provides different quality of service (QoS) levels for information dissemination in mobile ad hoc networks. To ensure a fair use of the transport media and support various message sizes, a message fragmentation solution was implemented. The proposed information dissemination solution was then deployed in a real wireless ad-hoc environment for further validation and testing. Using experiments with six nodes and various test scenarios, this research verified the functionality and characterized the performance of the proposed system. It was observed that the link-state nature of information dissemination solution helped it to adapt to topology changes. It was also realized that service discovery latency after information convergence in the network was independent of the number of nodes between the service providers and clients. The experiments also confirmed that the immediate message delivery scheme provides superior quality of service to registered users in presence of radio interference and other delays caused by Multipoint Relay Nodes (MPR) message forwarding in OLSR. / Master of Science
80

Régulations moléculaires des facteurs lymphangiogéniques dans les pathologies vasculaires / Molecular regulations of lymphangiogenic growth factors in vascular pathologies

Morfoisse, Florent 14 December 2015 (has links)
Le système lymphatique a pour rôle principal de drainer les fluides tissulaires et de participer à la surveillance immune. La lymphangiogenèse est principalement activée par deux facteurs : les vascular endothelial growth factors-C et -D (VEGF-C et VEGF-D). Ces facteurs participent à la progression métastatique à la fois en stimulant la prolifération des vaisseaux lymphatiques dans la tumeur et en périphérie et en provoquant la dilatation des vaisseaux collecteurs facilitant ainsi le passage des cellules tumorales de la tumeur primaire aux ganglions lymphatiques. Lors de son développement, une tumeur est soumise à de nombreux stress cellulaires tels que l'hypoxie, l'inflammation ou la déprivation en nutriments. Ma thèse a donc été consacrée à l'analyse des régulations moléculaires permettant une surexpression des facteurs lymphangiogéniques en condition de stress cellulaire. Lors d'un premier projet de recherche j'ai démontré que l'hypoxie réduit la transcription de VEGF-C ainsi que sa traduction coiffe-dépendante mais activait une traduction médiée par un site interne d'entrée du ribosome (IRES). De plus, cette activation de la synthèse de VEGF-C en hypoxie est indépendante de HIF-1a et stimule la lymphangiogenèse dans les tumeurs ainsi que dans les ganglions lymphatiques participant ainsi à la dissémination tumorale. Dans un second temps, j'ai démontré que le VEGF-D possédait lui aussi un IRES activé par un choc thermique. L'activité de l'IRES du VEGF-D est régulée par la localisation subcellulaire d'un facteur trans-activateur de l'IRES (ITAF) : la nucléoline. Cette protéine est exportée du noyau vers le cytoplasme lors d'un choc thermique. Ce processus est inhibé par un traitement avec un anti-inflammatoire non stéroïdien ce qui supprime l'activation de la traduction IRES dépendante du VEGF-D. Enfin lors d'un troisième projet, j'ai travaillé sur le lymphœdème secondaire, une pathologie caractérisée par une destruction du système lymphatique où la lymphangiogenèse doit être stimulée. J'ai évalué l'impact de l'hormonothérapie, principal traitement du cancer du sein, sur l'expression du VEGF-C et -D. J'ai démontré que l'estradiol stimulait l'expression de ces facteurs alors que l'hormonothérapie diminue leur synthèse et provoque une destruction de l'endothélium lymphatique. En conclusion, mes trois projets de thèse m'ont permis d'étudier les régulations moléculaires des deux facteurs lymphangiogéniques principaux dans des pathologies provoquées par une lymphangiogenèse excessive ou insuffisante. / Tumor lymphangiogenesis promotes lymph node metastasis using two mechanisms consisting of lymphatic vessels proliferation and dilatation to facilitate tumor spread. Lymphangiogenesis is mainly promoted by two growth factors: the vascular endothelial growth factor C and D. My PhD was focused on the molecular regulations inducing a tumoral over-expression of these two factors during stress. I demonstrated that hypoxia reduced VEGF-C transcription and cap-dependent translation while activating an Internal Ribosome Entry Site (IRES)-dependent mechanism of translation. This upregulation of VEGF-C in hypoxia is independent of HIF-1a; and stimulates lymphangiogenesis in tumors and lymph nodes and contribute to lymphatic metastasis. Then, I have discovered that VEGF-D had an IRES selectively activated by heat shock. VEGF-D IRES is regulated by a subcellular relocalization of an ITAF, the nucleolin. This molecular process is reversed by non-steroidal anti-inflammatory drugs (NSAID) that decrease VEGF-D IRES translation initiation by targeting the nucleolin. Finally, I worked on secondary lymphedema, a pathology that is characterized by a disruption of the lymphatic network where lymphangiogenesis thus need to be restored. In this condition, I have evaluated the impact of hormone therapy, the main treatment for breast cancer, on the regulation of lymphangiogenic factors. I found that estradiol stimulates the expression of VEGF-C and-D contrary to the hormone therapy that inhibits VEGF-C and -D and thus mediates a disruption of the lymphatic endothelium. Taken together, my PhD projects have allowed me to study the regulations of VEGF-C and -D in pathologies mediated either by an excessive or an insufficient lymphangiogenesis.

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