Oral health has dramatically improved in most industrialized countries over the latter half of the 20th century. However, profound oral health disparities still exist especially for those most at risk of developing oral diseases and associated systemic consequences such as populations residing in long-term care facilities. Despite the growing body of literature that supports the link between oral microflora and the importance of oral hygiene in limiting the risk of pneumonia development, there are still gaps in our knowledge to effectively manage this risk. The research included in this dissertation sought to further our understanding of oral health and oral care in the context of pneumonia pathogenesis (chapter 3) and, by exploring the perspective of various stakeholders in oral health, we sought to further understand the factors that influence care provision (chapter 5). Additionally, a novel knowledge translation approach was tested to challenge traditional oral care interventions in order to promote improvements in front-line oral care practices (chapter 6). The relationship between oral microflora, oral care and pneumonia was found to be complex. It directs us to consider converging risk factors including a patient’s health status, health behaviours and access to oral care services. Different professional groups were found to possess different definitions of oral health, which influenced both their motivation to provide care as well as their focus of care. Definitions of oral health could also potentially influence the saliency of different types of oral care information to different targeted groups; therefore, this should be considered in developing education and training initiatives aimed at improving the provision of oral care. An appreciative knowledge translation approach was found to be effective in bridging the gap between oral care knowledge and the provision of care. Regardless of the type of intervention chosen, organizations were reported to play a crucial role in promoting oral health and supporting the successful implementation of oral care programs.

Antipsychotic use is an important issue in long-term care (LTC) homes due to their widespread use, the potential for serious adverse events and limited evidence about their efficacy in treating behavioural and psychological symptoms of dementia. Rates of antipsychotic use vary across LTC homes, but little is known about the contribution of physicians to this variation. This study documented the characteristics of physicians who regularly treated residents in Ontario LTC homes and examined variation in antipsychotic prescribing across physicians. In a population-based retrospective cohort of LTC residents, 637 (52.8%) of 1,207 LTC physicians cared for 46,365 (90.4%) of all residents. Overall, 27.3% of residents received antipsychotic therapy, but extremely high prescribers prescribed antipsychotics to 42.8% of their patients. Variation in physician antipsychotic prescribing persisted after controlling for clinical and behavioural resident characteristics. This variation was reduced by 47.1% when LTC homes were accounted for in multilevel cross-classification logistic regression models.

This work is intended to examine the history of the formation and breakdown of Comintern-CCP relations between 1921 and 1939. Achieving such an objective entails an analysis of Braun's experiences in China, with an emphasis on the events leading up to and including the Long March. Of particular interest is the shifting emphasis from political to military strategy as the source of internal conflict within the CCP. By chronicling the political shifts within the Party, the historical events, and the factors that resulted in the Comintern's fall from grace, it is hoped that the reader will come to better understand the role of Otto Braun and the Comintern amidst the chaos of civil war.

This study uses a grounded theory approach (Charmaz, 2006) in a small case study to examine if drama as praxis influences long-term care residents when presented as a recreational activity. When used as “praxis” (Taylor, 2000), drama focuses solely on the learning and personal growth of the participants. The growth of long-term care underscores the value of recreational programming for quality of life in these institutions; drama as praxis has not been widely used in this context. Elements of the literature review were used to identify areas where dramatic activities have demonstrated influence in educational contexts: • Engagement / Participation • Self-Confidence / Sense of Efficacy • Social Skills / Empathy • Creativity / Imagination • Cognitive Skill Development / Understanding These became sensitizing concepts for the creation of “drama as praxis” activities, presented in six sessions to a small group of residents at a long-term care residence in the Toronto area. Data collection was based on the researcher’s observations and participant interviews. Drama was found to have a recreational benefit impacting quality of life, with Engagement, Social Skills,, and Self-Confidence, the predominant benefits observed. Creativity and Cognitive Skill Development were less frequent. A Theory of the Recreational Benefit of Drama as Praxis was then developed to help the researcher understand why these benefits might be caused by drama. Based on theoretical sampling from recent research in gerontology and brain science, the theory highlights four beneficial components of drama as praxis: 1. Kinesthetics – Fosters engagement and memory retrieval 2. Play and Endorphinal Release – Triggers cognitive work without fear or fatigue 3. Imagination and Perspective-taking – Helps individuals retrieve emotional memories, develop different perspectives, and joyfully create 4. Narrative - Helps participants access and process events in their lives, past and present The study ends with a discussion of possible implications for the use of drama in long-term care but emphasizes that, due to the size of the sample, the results of the research cannot necessarily be assumed to apply in other contexts. Suggestions for further research are made that might address this and help to clarify the findings of the study.

Primary visual cortex is a classic model to study experience-dependent brain plasticity. In early life, if one eye is deprived of normal vision, there can be a dramatic change in the ocular dominance of the striate cortex such that the large majority of neurons lose responsiveness to the deprived eye and, consequently, the ocular dominance distribution shifts in favor of the open eye. Interestingly, the visual experience dependent plasticity following monocular deprivation (MD) occurs during a transient developmental period, which is called the critical period. MD hardly induces ocular dominance plasticity beyond critical period. The mechanisms underlying ocular dominance plasticity during the critical period are not fully understood. It has been proposed that long-term depression (LTD) may underlie the loss of cortical neuronal responsiveness to the deprived eye. However, discordant results have been reported in terms of the role of LTD and LTP in visual plasticity due to the lack of specific blockers. Here we report the prevention of the normally-occurring ocular dominance (OD) shift to the open eye following MD by using a specific long-term depression (LTD) blocking peptide derived from the GluR2 subunit of the a-amino-3-hydroxy-5-methyl-isoxazole-4-propionic acid receptor (AMPAR). We were able to prevent the shift of OD to the open eye with systemic or local administration of the GluR2 peptide. Both electrophysiological and anatomical approaches were taken to demonstrate the peptide effect. Moreover, enhancing LTD with D-serine, a NMDA receptor co-agonist, brought back the ocular dominance plasticity in adult mice subject to four-day MD and, therefore, reopened the critical period. Our data indicate that LTD plays an essential role in visual plasticity during the critical period and the developmental regulation of LTD may account for the closure of critical period in adult. In an additional study, we have found anisomycin, a protein synthesis inhibitor, produces a time-dependent decline in the magnitude of the field EPSP (fEPSP) in mouse primary visual cortex and that this anisomycin-mediated fEPSP depression occludes NMDA receptor dependent LTD. In contrast, another two protein synthesis inhibitors, emetine and cycloheximide, have no effect either on baseline synaptic transmission and or on LTD. We propose that anisomycin-LTD might be mediated by p38 MAP kinase since anisomycin is also a potent activator of the P38/JNK MAPK pathway. In agreement with notion, the decline of the fEPSP caused by anisomycin can be rescued by the application of the P38 inhibitor SB203580, but not by the JNK inhibitor SP600125. The occlusion of LFS-LTD by anisomycin-induced fEPSP decline suggests that common mechanisms may be shared between the two forms of synaptic depression. Consistent with this view, bath application of the membrane permeant peptide discussed above, which specifically blocks regulated AMPA receptor endocytosis, thereby preventing the expression of LFS-LTD, prior to anisomycin treatment significantly reduced the anisomycin-induced decline of the fEPSP. In conclusion, this study indicates that anisomycin produces long-lasting depression of AMPA receptor-mediated synaptic transmission by activating P38 MAPK-mediated endocytosis of AMPA receptors in neonatal mouse visual cortex.

No description available.

El objetivo de esta tesis es modelar y predecir la volatilidad de las series financieras con modelos de volatilidad en tiempo discreto y continuo.En mi primer capítulo, intento modelar las principales características de las series financieras, como a persistencia y curtosis. Los modelos de volatilidad estocástica estimados son extensiones directas de los modelos de Gallant y Tauchen (2001), donde incluyo un elemento de retro-alimentación. Este elemento es de extrema importancia porque permite captar el hecho de que períodos de alta volatilidad están, en general, seguidos de periodos de gran volatilidad y viceversa. En este capítulo, como en toda la tesis, uso el método de estimación eficiente de momentos de Gallant y Tauchen (1996). De la estimación surgen dos modelos posibles de describir los datos, el modelo logarítmico con factor de volatilidad y retroalimentación y el modelo logarítmico con dos factores de volatilidad. Como no es posible elegir entre ellos basados en los tests efectuados en la fase de la estimación, tendremos que usar el método de reprogección para obtener mas herramientas de comparación. El modelo con un factor de volatilidad se comporta muy bien y es capaz de captar la "quiebra" de los mercados financieros de 1987.En el segundo capítulo, hago la evaluación del modelo con dos factores de volatilidad en términos de predicción y comparo esa predicción con las obtenidas con los modelos GARCH y ARFIMA. La evaluación de la predicción para los tres modelos es hecha con la ayuda del R2 de las regresiones individuales de la volatilidad "realizada" en una constante y en las predicciones. Los resultados empíricos indican un mejor comportamiento del modelo en tiempo continuo. Es más, los modelos GARCH y ARFIMA parecen tener problemas en seguir la marcha de la volatilidad "realizada". Finalmente, en el tercer capítulo hago una extensión del modelo de volatilidad estocástica de memoria larga de Harvey (2003). O sea, introduzco un factor de volatilidad de corto plazo. Este factor extra aumenta la curtosis y ayuda a captar la persistencia (que es captada con un proceso integrado fraccional, como en Harvey (1993)). Los resultados son probados y el modelo implementado empíricamente. / The purpose of my thesis is to model and forecast the volatility of the financial series of returns by using both continuous and discrete time stochastic volatility models.In my first chapter I try to fit the main characteristics of the financial series of returns such as: volatility persistence, volatility clustering and fat tails of the distribution of the returns.The estimated logarithmic stochastic volatility models are direct extensions of the Gallant and Tauchen's (2001) by including the feedback feature. This feature is of extreme importance because it allows to capture the low variability of the volatility factor when the factor is itself low (volatility clustering) and it also captures the increase in volatility persistence that occurs when there is an apparent change in the pattern of volatility at the very end of the sample. In this chapter, as well as in all the thesis, I use Efficient Method of Moments of Gallant and Tauchen (1996) as an estimation method. From the estimation step, two models come out, the logarithmic model with one factor of volatility and feedback (L1F) and the logarithmic model with two factors of volatility (L2). Since it is not possible to choose between them based on the diagnostics computed at the estimation step, I use the reprojection step to obtain more tools for comparing models. The L1F is able to reproject volatility quite well without even missing the crash of 1987.In the second chapter I fit the continuous time model with two factors of volatility of Gallant and Tauchen (2001) for the return of a Microsoft share. The aim of this chapter is to evaluate the volatility forecasting performance of the continuous time stochastic volatility model comparatively to the ones obtained with the traditional GARCH and ARFIMA models. In order to inquire into this, I estimate using the Efficient Method of Moments (EMM) of Gallant and Tauchen (1996) a continuous time stochastic volatility model for the logarithm of asset price and I filter the underlying volatility using the reprojection technique of Gallant and Tauchen (1998). Under the assumption that the model is correctly specified, I obtain a consistent estimator of the integrated volatility by fitting a continuous time stochastic volatility model to the data. The forecasting evaluation for the three estimated models is going to be done with the help of the R2 of the individual regressions of realized volatility on the volatility forecasts obtained from the estimated models. The empirical results indicate the better performance of the continuous time model in the out-of-sample periods compared to the ones of the traditional GARCH and ARFIMA models. Further, these two last models show difficulties in tracking the growth pattern of the realized volatility. This probably is due to the change of pattern in volatility in this last part of the sample. Finally, in the third chapter I come back to the model specification and I extend the long memory stochastic volatility model of Harvey (1993) by introducing a short run volatility factor. This extra factor increases kurtosis and helps the model capturing volatility persistence (that it is captured by a fractionally integrated process as in Harvey (1993) ). Futhermore, considering some restrictions of the parameters it is possible to fit the empirical fact of small first order autocorrelation of squared returns. All these results are proved theoretically and the model is implemented empirically using the S&P 500 composite index returns. The empirical results show the superiority of the model in fitting the main empirical facts of the financial series of returns.

Previous studies have suggested that iron PRBs, receiving high concentrations of inorganic constituents in groundwater, may experience passivation because of the accumulation of inorganic precipitates. In an iron PRB containing more highly reactive material, even though the initial contaminant removal rate is faster than for less reactive material, a faster migration of the contaminant removal front may occur due to the greater reactivity loss, caused by faster accumulation of secondary precipitates. In contrast, an iron PRB containing less reactive material may show a slower accumulation of precipitates, and thus will show a slower migration of the contaminant removal front over time. Thus, it is hypothesized that an iron material having moderate initial reactivity may be more advantageous than material having a higher reactivity in terms of long-term performance. The objective of this study was to test this hypothesis by evaluating the changes of the reactivities of different iron materials in the presence of dissolved CaCO₃. <br /><br /> Four different iron materials (Connelly, G-M, Ispat and Peerless) were selected for the column experiments. The changes in reactivities of the iron and formation of secondary precipitates over time were assessed, primarily by the iron corrosion rates, calculated from the hydrogen gas generation rates, by the cis-DCE removal rates and by the alkalinity profiles. The accumulation of precipitates in the four columns caused passivation of the iron. The passivation of the iron in turn resulted in migration of the mineral precipitation fronts as well as profiles of cis-DCE, TCE, VC, alkalinity, Eh, pH, and chloride. Connelly and G-M had longer periods of operation than Ispat and Peerless and thus their performance was the primary test of the hypothesis. G-M iron, which had the higher initial corrosion rate, compared to Connelly, showed a faster accumulation of precipitates near the influent end. The difference in accumulated precipitates resulted in a difference in the leading edge of the organic profiles and a significant difference in the pattern of passivation, indicating a faster passivation in the region near the influent end for G-M. <br /><br /> Model simulations were performed using the same fitting parameters but with different initial corrosion rate constants to further test the hypothesis. The model provided a reasonable representation of changing reactivities of the columns, being consistent with the observed data. In the simulation for long-term prediction, the cases of higher corrosion rates showed earlier breakthroughs and steeper curves than those of lower corrosion rates. Also, the predictions showed greater porosity loss for the case of higher corrosion rate. Thus, long-term predictions support the hypothesis. Accurate determination of model parameters such as cis-DCE degradation rate constants and iron corrosion rates are required for better predictions of long-term performance.

Direct care worker turnover and shortages plague long-term care, weakening its quality, heightening costs for governments and employers, and cyclically breeding further turnover and shortages of workers. To address these issues, I investigate why direct care workers chose employment in long-term care (LTC), assisted living (AL) and specific AL facilities. Data come from a mixed-methods study of 45 AL facilities in Georgia, including interviews with 400 direct care workers. Findings include qualitative data analyzed using a grounded theory approach and descriptive quantitative data. Care workers’ motivations for employment in LTC, AL, and specific AL facilities reflect a split between moral and material values for care work, and care workers’ motivations illustrate a process of reconciling moral and material values. Individuals become care workers for reasons that are both materialistic, like earning a living wage, and moralistic, like the desire to care for others. They take employment expecting it to be consistent with their moral ideals and to satisfy their economic needs. Various individual, facility, industry, and community level factors influence workers’ motivations, and these factors reinforce the inconsistency between moral and material values for care work. Considering the heightening demand for LTC and short supply of care workers, as well as the deindustrialization of the economy, several recommendations are made for policies and practices that would support workers’ motivations for employment in LTC. Areas for future research also are highlighted.

The effective acyl flux between phospholipids and neutral lipids is critical for a high level of the biosynthesis of very long chain polyunsaturated fatty acids (VLCPUFAs) such as arachidonic acid (ARA,20:4-5,8,11,14), eicosapentaenoic acid (EPA, 20:5-5,8,11,14,17) and docosahexaenoic acid (DHA, 22:6-4,7,10,13,16,19) which are essential for human health and wellbeing. Three membrane-bound enzymes, phosphatidylcholine:diacylglycerol cholinephosphotransferase (PDCT), cholinephosphotransferase (CPT) and ethanolaminephosphotransferase (EPT) from VLCPUFA-producing fungi were selected as candidates for my thesis research based on the hypothesis that these enzymes play important roles in acyl trafficking between phosphatidylcholine (PCs) and diacylglycerols (DAGs) during the biosynthesis of VLCPUFAs. Two putative PDCT cDNAs (PiPDCT1 and PiPDCT2) were cloned from Phytophthora infestans which encode polypeptides with two conserved domains and about 15% of amino acid identity to an Arabidopsis PDCT. However, in vitro assays in yeast Saccharomyces cerevisiae showed they did not have any PDCT activity. Four putative CPT and EPT cDNAs (PiCPT1, PiCPT2, PiEPT and TaCPT) were cloned from P. infestans and Thraustochytrium aureum which encode proteins with a conserved CDP-alcohol phosphotransferase motif and 22% to 26% of amino acid identity to the yeast CPT. In vitro assays indicated PiCPT1 and TaCPT had CPT activity, PiEPT had EPT activity and PiCPT2 did not have either activity. Substrate specificity assays showed that all the three functional CPT and EPT preferred VLCPUFA-containing DAGs as substrates with PiCPT1 being the most specific towards ARA-DAG and DHA-DAG. Real-time qPCR analysis revealed that the expression of PiCPT1 was up-regulated in P. infestans fed with exogenous VLCPUFAs. These results lead us to conclude that PiCPT1 is a VLCPUFAs-specific CPT which may play an important role in shuffling VLCPUFAs from phospholipids to storage neutral lipids, would thus have potential use in metabolic engineering of VLCPUFAs in heterologous systems including oilseed crops.