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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.
819951

Exploring the Experiences of Therapists After Participating in an Intensive Mindfulness Program

Lee, Tracie S. 05 December 2013 (has links)
The purpose of this study was to explore whether and in what ways an intensive eight-week Mindfulness-Based Symptom Management (MBSM) program might shape the therapeutic experiences of therapists. I used a hermeneutic phenomenological approach to interview and develop in-depth descriptions of four therapists’ experiences in relation to mindfulness and their therapeutic practices. The data collection consisted of: (1) a telephone screening interview; (2) pre-mindfulness training interview; (3) post-mindfulness training interview; (4) field notes based on my observations, subjective experiences, and beginning analyses; (5) and member-checks to verify the accuracy of my interpretations of participants’ interview responses. The results pointed to several common themes indicating the changes therapists described after participating in the mindfulness program. Themes denoting the reported changes were organized into three categories: (1) personal relationship with mindfulness; (2) relationship between mindfulness and therapeutic experiences; and (3) mindfulness-oriented interventions performed in therapy. The findings indicated that mindfulness training is associated with the enhancement of important relational attitudes and skills of therapists, including more acceptance of where clients are at, more presence in therapy, increased capacity to listen, openness and curiosity, and more compassion and empathy. In addition, mindfulness training may be linked to improved reflexive abilities, which has implications for more intentional and ethical decision-making in therapy. Further, the findings also indicated that mindfulness training may be linked to improvements in emotion regulation by decreasing stress, increasing feelings of relaxation and calmness, improving awareness of negative emotional and cognitive states as well as the ability to interrupt these negative cycles. As such, this study pointed to several potential benefits for the inclusion of mindfulness training in therapists’ self-care practices as well as in therapist education.
819952

Synthesis and Evaluation of Photocatalytic Properties of BiOBr for Wastewater Treatment Applications

Ahmad, Ayla 05 December 2013 (has links)
Visible light-driven photocatalysis has shown considerable potential in the area of clean and renewable energy, as well as in wastewater treatment. This thesis describes the synthesis, characterization and applicability of a visible-light active photocatalyst, bismuth oxybromide (BiOBr). The photocatalytic activity of BiOBr was investigated through its preparation via hydrothermal and solvothermal synthesis routes under various conditions. Hydrothermal catalyst was prepared using non template based method while for solvothermal synthesis CTAB was used as a template. Parameters of temperature and time of thermal treatment were optimized for each synthesis method and overall tests for catalyst dosage and recyclability were performed. An overall optimal route leading to high photocatalytic performance was also proposed based on the obtained results. Studies were also conducted to examine the applicability of optimally synthesized BiOBr in drinking water applications by studying catalyst-mediated disinfection of E. coli and degradation of phenol. Favourable results were obtained, confirming the prospective application of BiOBr as a viable photocatalyst for disinfection. Furthermore, the potential of enhancing BiOBr to further improve its performance is described through synthesis of a novel PdCl2/BiOBr based photocatalyst. Overall, the performance of BiOBr under various conditions in this study establishes its potential as a holistic photocatalyst and merits further development.
819953

The Geochemistry and Runoff Process in Wolf Creek Research Basin, Whitehorse, Yukon Territory

Li, Tianjiao 05 December 2013 (has links)
This study investigates the runoff process and groundwater behavior in a subarctic watershed called Wolf Creek Research Basin, in Whitehorse, Yukon Territory, Canada. This basin is underlain by discontinuous permafrost that is typical of high latitude watersheds. Goundwater supports the stream flow year round and dominated the hydrology in most of the study period as baseflow. The baseflow was concentrated in dissolved ions. However, the baseflow was diluted during the melt season in May and June of 2012. Multiple chemical and isotopic tracers were used to develop a robust three-component (groundwater, soilwater and precipitation) mixing model for runoff generation. The concentrations of weathering ions decreased with the increased discharge during the melt. Soilwater was responsible for about 60% of the streamwater on the hydrograph in the melt season. The infiltration of the meltwater from the snowpack and the thawed water from the seasonal frost to the baseflow existed. The tritium concentrations indicated that there was fast moving hydrogeological system within the basin. The baseflow was also characterized as relatively enriched in both 13C and 14C, and concentrated in DIC. DIC was the major loss of carbon in Wolf Creek Research Basin.Le pergélisol est grandement sous-jacent dans les bassins-versants à haute latitude. Cette étude examine le processus de ruissellement et le comportement des eaux souterraines dans un bassin-versant subarctique de Wolf Creek, à Whitehorse, territoire du Yukon au Canada. Les eaux souterraines soutenaient l’écoulement fluvial et dominaient l’hydrographe comme débit de base durant la majorité de la période d’étude. Le débit de base était concentré d’ions dissipés. Par contre, le débit de base était dilué durant la saison des fontes au mois de mai et juin 2012. Plusieurs traceurs chimiques et isotopiques étaient utilisé afin de développer un modèle de trois composants (eau souterraine, eau interstitielle de sol et précipitation) de ruissellement. Les concentrations de la déségrégation des ions diminuaient avec l’augmentation du débit durant la fonte. Les eaux interstitielles des sols étaient responsables de 60% de l’eau de ruisseau sur l’hydrographe durant la saison de fontes. L’infiltration de l’eau de fonte du manteau neigeux et l’eau du gel du débit de base existaient. Les concentrations de tritium indiquent qu’il y avait un système hydrogéologique qui se déplaçait à grande vitesse dans les limites du bassin. Le débit de base était aussi caractérisé comme étant enrichi en 13C et 14C, avec des concentrations en carbone inorganique dissous.
819954

The Snf2h and Snf2l Nucleosome Remodeling Proteins Co-modulate Gene Expression and Chromatin Organization to Control Brain Development, Neural Circuitry Assembly and Cognitive Functions

Alvarez-Saavedra, Matias A. 05 December 2013 (has links)
Chromatin remodeling enzymes are instrumental for neural development as evidenced by their identification as disease genes underlying human disorders characterized by intellectual-disability. In this regard, the murine Snf2h and Snf2l genes show differential expression patterns during embryonic development, with a unique pattern in the brain where Snf2h is predominant in neural progenitors, while Snf2l expression peaks at the onset of differentiation. These observations led me to investigate the role of Snf2h and Snf2l in brain development by using conditionally targeted Snf2h and Snf2l mice. I selectively ablated Snf2h expression in cortical progenitors, cerebellar progenitors, or postmitotic Purkinje neurons of the cerebellum, while Snf2l was deleted in the germline. I found that Snf2h plays diverse roles in neural progenitor expansion and postmitotic gene expression control, while Snf2l is involved in the precise timing of neural differentiation onset. Gene expression studies revealed that Snf2h and Snf2l co-modulate the FoxG1 and En1 transcription factors during cortical and cerebellar neurogenesis, respectively, to precisely control the transition from a progenitor to a differentiated neuron. Moreover, Snf2h is essential for the postmitotic neural activation of the clustered protocadherin genes, and does so by functionally interacting with the matrix-attachment region protein Satb2. My neurobehavioral studies also provided insight into how Snf2h loss in cerebellar progenitors results in cerebellar ataxia, while Snf2h loss in cortical progenitors, or in postmitotic Purkinje neurons of the cerebellum, resulted in learning and memory deficits, and hyperactive-like behavior. Molecularly, Snf2h plays an important role in linker histone H1e dynamics and higher order chromatin packaging, as evidenced by loss of chromatin ultrastructure upon Snf2h deletion in progenitor and postmitotic neurons. I further demonstrated that Snf2h loss in a neuronal cell culture model results in reduced H1e deposition, and that overexpression of human SNF2H or SNF2L upon Snf2h knockdown rescues this biochemical dysfunction. My experiments suggest that Snf2h and Snf2l are regulatory nucleosome remodeling engines that co-modulate the gene expression programs necessary for proper brain development, maturation and function.
819955

Analyzing Value Networks for Change Decision Making in a Collaborative Environment With a Case Study in Healthcare

Sharif, Soroosh 10 December 2013 (has links)
Management of Collaborative Networked Organizations faces various challenges in terms of decision-making. Particularly, in complex and multi-player environments, like healthcare, it is not easy to find the roots of low performance processes, and unmet goals. This research provides a framework, as well as associated techniques to analyze the value network, identify problematic actors, and consequently, find the best possible solution to change them. The proposed framework consists of two main components: Analyzing the value network, and Multi-Criteria Decision Making. To analyze the value network of a collaborative environment, in addition to the existing techniques, four complementary components are introduced: Actors’ value interchanges matrix, Value Gantt chart, Identifying problematic actors flowchart, and Actors’ ease of substitution table. Employing these hybrid analyses, decision makers gain a better understanding of the bottlenecks in the value network, current conditions and contributions of the involved actors, and the consequences of considering various alternatives. Then, by applying one of the Multi-Criteria Decision Making methods, and based on pre-defined criteria, possible alternatives are analyzed and outlined. As a proof of concept and validation of the proposed methods, we reviewed a scenario of patient flow and wait times in healthcare. We derive the value network for collaborative processes in a hospital, specify the roles’ of actors, identify the bottlenecks, then rank the solutions, and suggest possible changes to improve the performance of the collaborative environment.
819956

Phytochemical Investigations of Costa Rican Marcgraviaceae and Development of Insecticide Synergists

Carballo Arce, Ana F. 10 December 2013 (has links)
Substances of natural and synthetic origin were studied using analytical, bioassay guided isolation, metabolomics and medicinal chemistry techniques. In a section focused on the plant family Marcgraviaceae, a validated method for the quantification of six pentacyclic triterpenes (α and β Amyrin lupeol, ursolic acid, betulin and betulinic acid) in the Souroubea spp was developed. Quantification of the triterpenes in the crude extracts was achieved using HPLC-APCI mass selective detection. The calibration curves for the five triterpenes evaluated were highly linear (r2 >0.993) and percentage recovery from spiked samples were greater than 94% for all compounds. The LOD for betulinic acid was 0.01 µg for betulinic acid on column and LOQ was 0.03 µg. The method was successfully applied to 41 crude extracts from leaf and stem of Souroubea spp, from two locations in Costa Rica. The method is suitable for quality control of raw materials used in the manufacture of natural health products. The use of modern metabolomic techniques, UHPLC-QTOF allowed the identification of five putative makers that can potentially be used in distinguishing between the two Souroubea species. The validated method was used in the quantification of the above triterpenes in a total of thirteen Marcgraviaceae species collected in Costa Rica. It was established that betulinic acid and β- Amyrin could be used as makers for this family of tropical vines. These same thirteen plants extracts were evaluated in antifungal and quorum sensing inhibition bioassays. Marcgravia nervosa was the only species that showed significant activity in both bioassays. Bioassay guided fractionation of the crude ethanolic extract of M. nervosa led to the identification of 2-methoxynaphthoquinone as the bioactive compound responsible for the bioactivity. The crude leaf ethanolic extract from M. nervosa showed a significant inhibition of QS comparable or somewhat better than D. pulchra extracts with the M. nervosa extract showing stronger inhibiting QS with a halo of 21.8mm, more than D. pulcra extracts which generated a halo of 15.9mm. The active quinone has a MIC of 85 µM against Saccharomyces cerevisiaBY4741 (haploid) and 100 µM against Saccharomyces cerevisiae BY4743 (diploid) compared to berberine (positive control) with a MIC 600 µM for both strains. This quinone is not present in any of the other twelve species of Marcgraviaceae available to us. In work focusing on organic synthesis, a total of 57 semi-synthetic derivatives of dillapiol, safrol and piperonal were prepared and evaluated for their inhibitory activity in a CYP 3A4 bioassay to assess their potential use as pesticide synergists. The synergistic activity of dillapiol has been improved 45 fold; analog 31 has an IC50 = 0.2 µM compared with dillapiol IC50= 9.18 µM. A number of other compounds structurally related to 31 showed similar levels of activity. A screening of a compound library identified the amino sulfoxide 3 as a potential lead for the design of a selective connexin blocker with potential application in the treatment of spinal cord injuries. The use of X-ray crystallography permitted the correction of the original structure assigned to 3. Once the structure was corrected a total of 6 analogs were prepared. Compound 3 has the highest inhibition of GJIC whereas compound 8 and compound 2, reduced anionic hemi-channel activity. Compound 2 also reduced the cationic activity of the hemi-channels.
819957

Kinetics and Kinematics of the Overhand, Hybrid and Sidearm Shot of Lacrosse

Renaud, Susie 13 December 2013 (has links)
Lacrosse, Canada’s national summer sport, is a sport anchored in first nations’ tradition. Its growing popularity in North America has not been reflected by a similar interest in the scientific literature more specifically on the biomechanics of the lumbar spine with its throwing motion. The aim of this study was to describe the motions, forces and muscle actions of the lumbar spine with the hybrid, overhand and sidearm throw. Twelve subjects were asked to throw at maximal speed while captured by a 3D motion analysis system. Flexion, extension and axial rotation angular velocities as well as positive and negative powers in the two planes were calculated. The first research question pertained to consistency in angular velocities and powers between trials of a given throwing technique. Subjects showed a fairly high variation on all variables but mostly with the angular velocities in extension and the peak positive power in flexion/extension which had high coefficient of variations (CVs). The contralateral rotation velocity and the positive rotation power had the lowest CVs. Overall the CVs for powers exceeded the angular velocities’. The second research question addressed if a difference in variables was present between the three throwing methods. A significant difference was observed in the peak negative power in flexion/extension and the peak positive power in rotation. The contralateral rotation angular velocity also showed a significant difference but the sphericity assumption failed. No other variable showed a significant difference but the observed power for those variables was also quite small. Due to the lack of power and the further need for controlling some unforeseen sources of error, this study can be used as a pilot study to further define and improve future studies in the field of lacrosse biomechanics.
819958

A Proactive Risk-Aware Robotic Sensor Network for Critical Infrastructure Protection

McCausland, Jamieson 17 December 2013 (has links)
In this thesis a Proactive Risk-Aware Robotic Sensor Network (RSN) is proposed for the application of Critical Infrastructure Protection (CIP). Each robotic member of the RSN is granted a perception of risk by means of a Risk Management Framework (RMF). A fuzzy-risk model is used to extract distress-based risk features and potential intrusion-based risk features for CIP. Detected high-risk events invoke a fuzzy-auction Multi-Robot Task Allocation (MRTA) algorithm to create a response group for each detected risk. Through Evolutionary Multi-Objective (EMO) optimization, a Pareto set of optimal robot configurations for a response group will be generated using the Non-Dominating Sorting Genetic Algorithm II (NSGA-II). The optimization objectives are to maximize sensor coverage of essential spatial regions and minimize the amount of energy exerted by the response group. A set of non-dominated solutions are produced from EMO optimization for a decision maker to select a single response. The RSN response group will re-organize based on the specifications of the selected response.
819959

An Application Framework for Monitoring Care Processes

Baarah, Aladdin 17 December 2013 (has links)
Care process monitoring is important in healthcare domains to provide precise and detailed analytics on patients, providers, and resources participating in a care process and their status. These analytics are used to keep track of whether the quality of care goals set by healthcare organizations are satisfied and ensure that legislative and organizational guidelines are followed. The complexity of care process monitoring can vary depending on whether the care process takes place in a hospital or out in the community, and it can vary depending on the complexity of the information technology infrastructure that is in place to support the care process. A Care Process Monitoring Application (CPMA) is a software application which collects and integrates data from various sources while a care process is being provided, in order to provide performance reporting of metrics that are used to measure how well the performance goals and guidelines for the care process are being met. In our research, we have studied how CPMAs are built in order to improve the quality of their engineering. The significant challenge in this context is how to engineer a CPMA so that the engineering process is repeatable, produces a CPMA of consistent high quality, and requires less time, less effort and less complexity. This thesis proposes an application framework for care process monitoring that collects and integrates events from event sources, maintains the individual and aggregate states of the care process and populates a metrics data mart to support performance reporting. Our contributions are the following: a state-based application meta-model of care process monitoring, a care process monitoring architectural pattern, and finally, a behavior driven development methodology for CPMAs based on our meta-model and architectural pattern. Our results are validated through three different case studies in which we collaborated with two different health care organizations to build and deploy CPMAs for two different care processes (one hospital-based, the other community-based) in collaboration with healthcare clinicians and researchers.
819960

Silicalite-1 Membranes Synthesis, Characterization, CO2/N2 Separation and Modeling

Tawalbeh, Muhammad 17 December 2013 (has links)
Zeolite membranes are considered to be a promising alternative to polymeric membranes and they have the potential to separate gases under harsh conditions. Silicalite-1 membranes in particular are easy to prepare and suitable for several industrial applications. In this research project, silicalite-1/ceramic composite membranes were prepared using the pore plugging hydrothermal synthesis method and supports with zirconium oxide and/or titanium oxide as active layers. The effect of the support’s pore size on the morphology and permeation performance of the prepared membranes was investigated using five supports with different active layer pore sizes in the range of 0.14 – 1.4 m. The prepared membranes were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), electron diffraction spectrometer (EDS), single gas and binary gas mixtures permeation tests. The results confirmed the presence of a typical silicalite-1 zeolite structure with a high internal crystalline order grown inside the pores of the active layer of the supports, with a dense film covering most of the supports active layers. Silicalite-1 crystals in the prepared membranes were preferably oriented with either a- or b-axes perpendicular to the support surface. Single gas permeation results illustrated that the observed permeances were not directly related to the kinetic diameter of permeants. Instead, the transport of the studied gases through the prepared membranes occurred by adsorption followed by surface diffusion mechanism. Binary gas tests performed with CO2 and N2 mixtures showed that the prepared membranes were selective and very permeable with CO2/N2 permselectivities up to 30 and a CO2 permeances in the order of 10-6 mol m-2 Pa-1 s-1. A model was developed, based on Maxwell−Stefan equations and Extended Langmuir adsorption isotherm, to describe the transport of binary CO2 and N2 mixtures through the prepared silicalite-1 membranes. The model results showed that the exchange diffusivities (D12 and D21) were less dependent on the feed pressure and feed composition compared to the permeances and the permselectivities. Hence, they are more appropriate to characterize the intrinsic transport properties of the prepared silicalite-1 membranes.

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