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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.
301

Capacity building for peace? The European Union's impact on security sector reform in Moldova and Georgia

Pajalic, Marko 05 1900 (has links)
The recent enlargements of the European Union brought about a strategic shift in the EU’s approach to conflict management and security in the eastern neighbourhood. The Partnership and Co-operation Agreements between the EU and Moldova contained no mention of the Transnistrian dispute, while the agreement between the EU and Geor gia included a vague phrase regarding political dialogue which may include the issue of conflict resolution. The addition of new members to the Union, however, expanded the EU into its neighbourhood and brought closer the unresolved territorial disputes. Concerns that were once further away are now right next door. While the former accession states might have served as buffers to these concerns, they can no longer, as members of the Union, be seen as such. Therefore, there is a greater need to address security issues, such as the ‘frozen conflicts’ bordering the EU. This thesis will examine the evolution of the EU’s responses to security chal lenges in the Eastern neighbourhood, and assess the role the EU plays in addressing these ‘frozen conflicts’ through the framework of the European Neighbourhood Policy. Fur ther, this thesis will argue that the EU has thus far exerted limited direct pressure towards direct resolution of these conflicts and has instead approached regional stability through a variety of other indirect and long term means, such as the pursuit of economic growth and political stability. In particular, the research will look at the security sector reform (SSR) and will focus on the EU’s impact, or Europeanization, in the rule of law and border management sectors of Moldova and Georgia. It will be shown that these two sectors are related to promoting political stability and economic growth, which is in line with the EU’s effort to support development in Moldova and Georgia, and thus indirectly address ‘frozen conflict’ resolution by. altering the incentive structures. This thesis will conclude that the EU does have an impact on the rule of law and border management sectors and subsequently some impact on the ‘frozen conflict’ in Moldova but less so on the conflicts in Georgia.
302

Using genotypic and phenotypic methods to determine the HIV co-receptor phenotype in the clinical setting

Low, Andrew John 05 1900 (has links)
Objective: The human immunodeficiency virus type 1 (HIV-1) currently infects over 30 million people worldwide. It uses one of two main co-receptors to infect cells. The primary objective of this thesis is to evaluate genotypic and phenotypic assays for co-receptor usage in the clinical setting and investigate approaches for improvement of these assays. Methods: The concordance of recombinant co-receptor phenotyping assays and the predictive ability of genotype-based methods including the ‘11/25’ rule, position specific scoring matrices (PSSMs), and support vector machines (SVMs) were evaluated in the clinical setting using patient-derived plasma samples. Samples and patient data were evaluated in cross-sectional analyses from a retrospective population-based cohort of HIV-infected individuals enrolled in the HIV/AIDS Drug Treatment Program in British Columbia, Canada. Results: Current implementations of HIV V3 region-based predictors for HIV co-receptor usage tested on patient derived samples are inadequate in the clinical setting, primarily due to low sensitivities as a result of difficult to detect minority species. Recombinant phenotype assays also show discordances when tested against each other on the same set of patient derived samples, raising doubts if any of these assays can truly be considered a ‘gold standard’. Significant associations between clinical progression, viral sequence-based predictors of co-receptor usage and the output of recombinant assays are observed, suggesting that sensitivity can be improved by incorporating CD4% into genotype-based predictors. This is verified with a SVM model which showed a 17% increase in sensitivity when CD4% was incorporated into training and testing. Conclusion: This work in this thesis has exposed the difficulty in determining the co-receptor phenotype in the clinical setting, primarily due to minority species. Although genotypic methods of screening for HIV co-receptor usage prior to the administration of CCR5 antagonists may reduce costs and increase turn-around time over phenotypic methods, they are currently inadequate for use in the clinical setting due to low sensitivities. Although the addition of clinical parameters such as CD4 count significantly increases the predictive ability of genotypic methods, the presence of low-levels of X4 virus continues to reduce the sensitivity of both genotypic and phenotypic methods.
303

THE EFFECTS OF NICOTINE ON VIDEO LOTTERY TERMINAL GAMBLING IN REGULAR GAMBLERS WHO SMOKE

McGrath, Daniel Stephen 13 November 2012 (has links)
A growing body of evidence has established that smoking and gambling frequently co-occur. Despite high rates of co-occurrence, few studies have attempted to examine the extent to which nicotine can directly affect gambling behaviour. This dissertation further explores the relationship between smoking and gambling through a secondary data analysis and two laboratory-based experiments. First, a secondary data analysis was conducted using epidemiological data collected from a gambling prevalence survey in Newfoundland and Labrador. The results from this analysis revealed several associations between smoking and past 12 month gambling. Significant relationships were found between smoking and problem gambling severity scores, use of alcohol/drugs while gambling, money spent gambling, use of video lottery terminals (VLTs), and reasons for gambling related to positive reinforcement/reward and negative reinforcement/relief. Experiment 1 consists of a laboratory investigation of the acute effects of nicotine on subjective and behavioural responses to VLT gambling among gamblers who smoke. Twenty-eight (15 male) regular gamblers who smoke daily took part in two double-blind laboratory sessions where subjective and behavioural responses to gambling were assessed following administration of nicotine inhalers (NI; 4mg deliverable) or placebo inhalers (PI). It was found that NI significantly decreased tobacco-related cravings but did not affect gambling-related cravings, VLT betting, or subjective responses. In Experiment 2, the acute effects of nicotine on subjective, physiological, and behavioural gambling responses were examined in VLT players who smoke following exposure to gambling-related cues. Thirty (20 male) VLT gamblers (identified as ‘moderate risk’ or ‘problem gamblers’) who smoke daily were assigned to a nicotine lozenge (NL; 4mg deliverable) or placebo lozenge (PL) condition. Subjective and behavioural responses were assessed at baseline, following lozenge administration, following neutral cues, and following gambling cues. It was found that NL significantly reduced tobacco-related cravings but didn’t affect gambling-related cravings, the decision to play a VLT, or other subjective responses. The aggregate findings of Experiments 1 & 2 indicate that acutely administered nicotine reduced tobacco-related cravings without increasing the reinforcing value of gambling. These results suggest that use of nicotine replacement therapies (NRT) may be a safe option for gamblers who are attempting to quit smoking.
304

Essays on Value Co-Creation, Co-Production, and the Interface between Operations and Recommender Systems

Demirezen, Emre Muzaffer 16 December 2013 (has links)
In this dissertation, I study coordination or collaboration settings that are either within company or at inter-organizational levels in the form of three essays. In the first essay, I study the relationship between a client and a vendor in value co-creation environments such as knowledge intensive services. I consider that the client gets utility from the project throughout the development period. The output is contingent on the effort levels of each party and I allow these effort levels to be dynamic. Hence, the client needs to optimally decide the terms of the payment so as to maximize the project output and minimize its cost. In my second essay, I study another value co-creation environment. In this case, unlike the first essay, I assume that the effort levels are not observable but might be monitored. In both essays, I analyze the performance of different contracts and find the best one for the client in diverse settings. Among several other results, I derive the conditions under which the client chooses not to observe vendor’s effort level and operates in a double moral hazard environment. In addition, I show that the remaining time of the project and the client’s valuation of the project regulate the behavior of the effort levels and some other characteristics in the collaboration. In the third essay, I consider a subscription based rental organization, such as Netflix and Blockbuster. In these environments, the satisfaction of customers de- pends on the availability of requested products. Hence, it is important for these firms to satisfy as much demand as possible. Recommender systems, in a DVD- rental context, are typically used to help customers in finding the right movies for them. However, recommendations can be utilized to shift demand among movies considering the inventory level and future demand to increase the number of satisfied customers or profitability. I address this issue by considering inventory in the optimization of recommender systems. I present several results that could be utilized by managers in order to make important tactical and operational decisions. Results suggest that the proposed approach may improve profitability of the firms substantially.
305

Co-immunoprecipitation analysis of the phosphoenolpyruvate carboxylase interactome of developing castor oil seeds

Uhrig, Richard Glen 09 January 2008 (has links)
Co-immunoprecipitation (co-IP) followed by proteomic analysis was employed to examine the phosphoenolpyruvate carboxylase (PEPC) interactome of developing castor oil seed (COS) endosperm. Earlier studies suggested that immunologically unrelated 107-kDa plant-type and 118-kDa bacterial-type PEPCs (p107/PTPC and p118/BTPC, respectively) are subunits of an unusual ~910-kDa hetero-octameric Class-2 PEPC complex of developing COS. The current results confirm that a tight physical interaction occurs between p118 and p107 since p118 quantitatively co-IP’d with p107 following elution of COS extracts through an anti-p107-IgG immunoaffinity column. No PEPC activity or immunoreactive PTPC or BTPC polypeptides were detected in the corresponding flow-through fractions. Although BTPCs lack the N-terminal phosphorylation site characteristic of PTPCs, Pro-Q Diamond Phosphoprotein staining, immunoblotting with phospho-(Ser/Thr) Akt substrate IgG, and phosphate-affinity PAGE demonstrated that the co-IP’d p118 was significantly phosphorylated at unique Ser and/or Thr residue(s). The co-IP of p118 and p107 was not influenced by their phosphorylation status. As p118 phosphorylation appeared unchanged 48 h following elimination of photosynthate supply due to COS depodding, the signaling mechanisms responsible for photosynthate-dependent p107 phosphorylation differ from those controlling p118’s in vivo phosphorylation. A third PEPC polypeptide of ~110-kDa (p110; RcPPC1) co-IP’d with p118 and p107 when depodded COS was used. Analysis of RcPpc1’s full-length cDNA sequence revealed p110’s identity with PTPCs, but that a pair of unique amino-acid substitutions occurs in its N-terminal sequence that may render p110 non-phosphorylatable in vivo. The plastidial pyruvate dehydrogenase complex (PDCpl) was identified as a novel PEPC interactor. Subcellular fractionation indicated that p118 and p107 are strictly cytosolic, but that PDCpl is targeted to both the cytosol and leucoplast of developing COS. Thus, a putative cytosolic metabolon involving PEPC and PDCpl could function to channel carbon from phosphoenolpyruvate to acetyl-CoA and/or to recycle CO2 from PDCpl to PEPC. / Thesis (Master, Biology) -- Queen's University, 2007-09-26 15:57:52.216
306

An Exploration of Life Expectancy Calculation Methods to Aid in Prostate Cancer Screening and Treatment Decision-Making

WYKES, Wykes, Dylan 08 April 2011 (has links)
Background: Life expectancy (LE) estimation is an important part of both screening and treatment decision-making for potentially curable prostate cancer. Clinicians’ estimation of patient life expectancy is typically made using population-based life tables and intuition and it is often inaccurate. This study explores methods to improve LE prediction by formally considering patient co-morbid illness status, in addition to age, in the development of a LE prediction tool. Methods: We conducted a population-based retrospective cohort study of patients from the Ontario Cancer Registry who were curative treatment candidates, identified between 1990-1998. We analyzed data on three sub-populations of this cohort, and we used LE estimates from the Ontario Life Tables. Each model utilized Cox proportional hazards analysis, and/or the declining exponential approximation of LE, to estimate the survival experience of potential curative treatment candidates, including the impact due to both age and co-morbid illness status. We developed five separate models, tested them using a random subset of the cohort study sample, and compared their predictive accuracy by measuring both discriminative ability and calibration to determine the ‘best’ model. We also conducted a supplementary analysis using logistic regression to develop a model to predict the probability of 10-year survival. Results: The ‘best’ of our models demonstrated a c-index of 0.65 and very good calibration. Further analysis revealed that our ‘best’ model violated the Cox PH assumption for age and it’s predictions consistently over-estimated observed LE. Supplementary analysis of the logistic regression prediction model demonstrated a c-index of 0.70. Conclusions: Our exploration of methods to predict LE resulted in modest predictive accuracy. However, based on the results of the logistic regression model, we conclude that the results of our LE prediction models are reasonable, and obtaining a high level of predictive accuracy may not be possible given just age and co-morbidities as predictors. Further studies should continue to explore these and other methods for LE prediction. External validation of the ‘best’ model from the current study is required before the model and its accompanying LE reference tables can be recommended for use in a clinical setting for screening or treatment decision-making. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2011-04-07 19:11:34.216
307

Classifying Websites into Non-topical Categories

Thapa, Chaman Unknown Date
No description available.
308

Co-gasification of biomass with coal and oil sands coke in a drop tube furnace

Gao, Chen Unknown Date
No description available.
309

Understanding the evolution of Beluga entrapment co- management in the Inuvialuit Settlement Region using Social Network Analysis

Kocho-Schellenberg, John-Erik 24 September 2010 (has links)
Co-management of fisheries in the Inuvialuit Settlement Region (ISR) began with the establishment of the Fisheries Joint Management Committee (FJMC) in 1986, one of the provisions of the Inuvialuit Final Agreement (IFA) signed in 1984. The agreement between the Inuvialuit and the Canadian Government with regards to renewable resource management was arranged as a collaborative management process that included knowledge and insight from both sides. This thesis uses the case of beluga entrapment in the Husky Lakes, NWT, to explore how co-management between the Tuktoyaktuk Hunter and Trapper Committee (HTC) and the Department of Fisheries and Oceans (DFO) has changed through time in structure and process, and to determine what impacts co-management has had on Inuvialuit involvement in management. Additionally, the linkage between co-management and adaptive capacity at the local level is analyzed in order to better understand how Inuvialuit involvement in fisheries management can have beneficial impacts on cultural preservation, youth education, and employment. This study employed the use of mixed qualitative and quantitative methods within a participatory approach, which aimed at including the community of Tuktoyaktuk in every step of the research process. Qualitative methods included informal discussions, semi-directed interviews, participant observation, and document analysis. Community research partners were also essential in accessing information and interviews. The quantitative method used in this study was the use of questionnaires for Social Network Analysis (SNA) in attempting to describe the changes in the management network over time.
310

Evaluation of co-culture sustainability and hydrogen production in an integrated fermentative microbial electrolysis cell

Wrana, Nathan 07 April 2011 (has links)
The relationship between the cellulolytic Clostridium termitidis and the electrogenic Geobacter sulfurreducens was evaluated in terms of co-culture sustainability and hydrogen production. Batch co-culture experiments in triplicate balch tubes were conducted using cellobiose as the sole carbon source and fumarate as a terminal electron acceptor. Despite high initial concentrations of acetate, no formate and very low H2 concentrations were detected, supporting the hypothesis that a syntrophic association exists between both bacteria. Co-culture growth characterization experiments were repeated in three microbial electrolysis cells and cellobiose as the sole carbon source. Initially, 9.7 mol-H2 mol-1-glucose was produced. However, a sustainable co-culture could not be maintained despite efforts to reduce reactor temperature and triple the medium’s buffering capacity. Strategies to achieve a sustainable co-culture are to minimize the carbon flux through C. termitidis by using complex substrates, maintain neutral operating conditions, and introduce acetogenic bacteria to control the flux of metabolic intermediates.

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