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Dendrohydrological reconstruction and hydroclimatic variability in southwestern British Columbia, CanadaMood, Bryan Joel 19 November 2019 (has links)
The hydrology of southwestern British Columbia is influenced by the region’s mountainous topography and climate oscillations generated from the Pacific Ocean. While much of the region is characterized as a temperate rainforest, recent summers are defined by record-breaking droughts that focus attention on the threat to regional water supply security likely to accompany future climate changes.
The limited length and distribution of hydrological records in southwestern British Columbia provide poor context for resource managers tasked with developing policy and water management strategies. The purpose of the dissertation was to describe long-term variability in several key hydroclimatic variables and hydroecological interactions that may be used in updated water resource policy and management strategies. Specifically, the research focused on developing long-term proxy records of April 1 snow water equivalent (SWE), summer streamflow, spring lake levels, and salmon abundance from tree ring records. A secondary goal of the dissertation was to identify the role and influence of several key climate oscillations on regional long-term hydroclimatic and ecological variability.
Freshet contributions from melting snow are critical for sustained summer streamflow in southwestern British Columbia. Even so, few manual snow survey stations exist within the region are of sufficient length to understand the full range of natural SWE variability. Long-term April 1 SWE records were constructed by establishing statistical relationships with the radial growth of high-elevation trees and April 1 SWE records. Explaining 51% and 73% of the total variance in the instrumental SWE records in coastal and continental settings, the reconstructions provide high-resolution descriptions of April 1 SWE over the past three centuries and help position the remainder of the dissertation. Negative phases of the Pacific Decadal Oscillation (PDO) and El Niño-Southern Oscillation (ENSO) were shown to strongly influence April 1 SWE totals. Both reconstructions illustrate repeated step-changes in April 1 SWE during the last 300 years and show that coastal areas may be more sensitive to annual variability than snowpack that accumulates in more continental locations.
Water shortages in the Metro Vancouver area in recent summers are linked to low total winter snowpack and early spring melt. Dendrohydrological analysis of dry-season streamflow was conducted to determine if the instrumental range has been underestimated over the past several centuries. A regionalized record of July-August streamflow for the Capilano and Seymour watersheds, which supply the Metro Vancouver area, was modelled from present to 1711using tree-rings. Explaining 54% of total variance over the instrumental period, the models show that below-average streamflow events are becoming more frequent. When compared to those characterizing the past 300 years, streamflow totals from 1977 to present have consistently fallen well-below the average long-term discharge. Further analyses indicated that negative ENSO and PDO conditions strongly influenced July-August runoff trends since 1711, as have climate regimes related to the Pacific North American pattern (PNA).
The increased frequency in recent years of reduced summer runoff in southwestern British Columbia has led many communities to rely on natural and dammed reservoirs to supplement their water needs. Where communities rely on natural lakes, this dependence may have socioeconomic consequences if lake levels fall below those necessary to supply built infrastructure. Unfortunately, there are few lake level records in southwestern British Columbia and none of sufficient duration to understand the full range of variability in natural lake systems. Harrison Lake is the only natural lake with a lake level record exceeding 50 years. Using the average April water level dataset, a dendrohydrological model was constructed that explained 49.5% of total variance. The model was used to reconstruct a proxy record of April water levels spanning the interval from 1711 to 1980. Averaging 9.37 m in depth, lake levels in Harrison Lake ranged from 8.9 to 10.0 m over the past 300 years. These variations were shown to be statistically associated with negative and positive phases of ENSO and positive phases of PDO. April water levels in Harrison Lake have been, on average, 0.13 m lower since the mid-1930s compared to the previous 200 years. This reduction in storage capacity amounts to a loss of almost 300-million litres of stored water since the start of instrumental records.
Salmon play a vital economic, cultural, and social role in many southwestern British Columbia communities. There is concern that salmon populations in the region are under threat, as changing climates alter and impact their spawning habitat. While various lines of research have sought to determine the response of salmon to these changing conditions, population records that extend only to 1951 hinder a complete understanding of the impacts. Two dendroecological models were constructed to provide a longer-term perspective of regional salmon-climate relationships. Explaining 48.2% and 48.9% of variance in observed Chinook and Coho salmon abundance since 1951, the models were used to construct proxy escapement records extending to the 1700s. Spectral analysis revealed that the reconstructions account for generational life histories and that low-frequency climate variability was associated with fluctuations in abundance. Both the Chinook and the Coho reconstructions show phase dependent relationships to climate oscillations generated from the Pacific Ocean. The Coho record is strongly linked to negative winter and spring ENSO, while the Chinook record was shown to be associated with negative PDO conditions. The identified relationships to teleconnections generated in the Pacific Ocean to our record indicates that both species are sensitive to oceanic interactions prior to entering natal habitats. Taken together, the reconstructions illustrate that the observational record encompasses a period of lower-than-average abundance and that neither accounts for the full range of variability in annual abundance when considered over the past three centuries.
The proxy tree-ring records presented in this dissertation provide new information about climate-water resource relationships in southwestern British Columbia. Significant phase-dependent associations, especially to negative phases of the PDO and ENSO, were shown to exert long-term influences on the state of several critical hydroclimatic variables over the last 300 years. Additionally, the research illustrates that over the instrumental period, both streamflow and lake volumes in the region have consistently remained below those characterizing the previous two to three centuries. These findings are of direct use to resource managers tasked with developing new policy and strategies under present and future climate change, in that they offer singular insights into the full range of natural hydroclimatic variability in southwestern British Columbia. / Graduate
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Employee Turnover in the Long-Term Care IndustryBryant, Olalya Ayanna 01 January 2017 (has links)
Employee turnover costs long-term care facilities billions of dollars on an annual basis. The purpose of this correlational study was to examine the relationships between employee turnover intention of certified nursing assistants (CNAs) in the long-term care industry and employee compensation, engagement, job satisfaction, motivation, and work environment. The predictor variables were employee compensation, engagement, job satisfaction, motivation, and work environment. The criterion variable was employee turnover intention. The population of interest consisted of CNAs who were residents of Florida, over the age of 18 years, and employed in the long-term care industry. The theoretical framework that grounded this study was the motivational-hygiene theory. For this study, a sample of 157 participants completed an electronic survey. Multiple linear regression analyses predicted the dependent variables, R-² = .34, F(5, 151) = 15.22, p < .0001. The multiple regression model with 4 of the 5 predictors accounted for significantly more variance in turnover intention than would be expected by chance. Correlation tests resulted in statistically significant inverse relationships between employee turnover intention and employee compensation, engagement, job satisfaction, and work environment. The negative correlation observed between motivation and turnover intention was not statistically significant. The findings in this study may contribute to positive social change by reducing turnover intention while improving the quality of care and reducing costs of care that affect the lives of the long-term care residents, concerned family members, and significant others.
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Systematic Review of Retention of Direct-Care Workers in Long-term Care FacilitiesGoins, Regina Evonne 01 January 2015 (has links)
Turnover among direct-care workers in long-term care (LTC) facilities is high, and has a significant impact on residents, leaders, and owners of LTC facilities. The overall turnover costs are also substantial and constitute a significant financial burden in LTC facilities. This systematic review of the literature examined, retention strategies for direct-care workers in the LTC workforce. The information may be used to develop and provide practice recommendations that will help improve retention rates among direct-care workers in LTC facilities. The project design involved a systematic examination of English-only studies from 2001-2004, retrieved from 3 major databases: CINAHL with Medline simultaneous, ProQuest, and Ovid resources. The review led to the identification of 858 publications out of which 17 articles met the inclusion criteria. The manifested variables were critically analyzed and grouped into 8 categories: job training, management style, acknowledgement of accomplishments, career advancements, benefits, peer mentoring, competitive wages and work load. The findings from this systematic review of the literature suggest that several factors affect turnover rates in the LTC setting, including job training, management style, acknowledgement of accomplishments, career advancements, benefits, peer mentoring, competitive wages and work load. This project aims to provide insight to project developers, administrators, researchers, and policy makers concerning factors that affect retention. The information can be used as a catalyst for positive social change and reduce the turnover crisis among direct-care workers in the long-term care setting.
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Diminishing Incontinence in Long-Term Care using Electronic Health RecordsRodgers, Catherine 01 January 2014 (has links)
Urinary incontinence affects up to 70% of residents living in a long-term care facility and can affect their quality of life. Specifically, urinary incontinence has a direct impact on older adults in regards to self-esteem, pressure ulcer development, falls, urinary tract infections, and psychosocial wellbeing. The goal of this quality improvement pilot project was to determine if an electronic health record (EHR) assessment tool could help older adults remain continent longer and assist in maintaining an independent lifestyle. Orem's self-care deficit theory and social cognitive theory were used to determine how the electronic health record incontinence template could be used to monitor residents for incontinence and affect the incidence of incontinence. Out of 25 residents, 13 met the requirements for inclusion in the pilot study. Quantitative data were collected and documented in the EHR for 4 weeks and compared to the immediate 4 week period post-implementation of the EHR template. Descriptive analyses of pre- and post-implementation EHR assessments showed there were no EHR assessments completed pre-implementation and 2 residents out of 13 had EHR assessments completed post-implementation. The available data suggested that the EHR template, if edited, could be effective for tracking incontinence. The template needed to address bladder incontinence only rather than bowel and bladder. Feedback from nursing staff indicated that a future study should be conducted over a longer period than 4 weeks to see if results would remain consistent. Nurses working in the long term care environment would benefit from reading this project. This study contributes to social change as evidenced by the residents who remained continent longer by having individual toileting plans partially developed by the template; therefore, they remained a viable part of the community.
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Care giving experiences of older husbands providing care for wives with dementiaBrown, Peter John, University of Western Sydney, College of Arts, School of Social Sciences January 2007 (has links)
As there were few studies of older husbands’ experiences associated with providing care at home for spouses with dementia, the researcher designed a two-stage study to examine their experiences, In stage one, a qualitative paradigm guided one-to-one interviews with sixteen care giver husbands to examine their care giving experiences. Analysis of the interview data guided the identification of four models of care giving related to the past, present and future and an overall model over time. In stage two, a comprehensive questionnaire was developed and questionnaire items were identified from multiple sources. In stage two the researcher utilized a quantitative approach to identify to investigate husbands’ experiences. A representative sample of 71 care giver husbands participated by completing the questionnaire and standardized measures of burden and depression along with other measures of husbands’ characteristics and experiences and levels of wives’ illness and associated behaviour. Predictive models of care giver burden were care giving seen as a ‘job’, effects of care giving on the husband-wife relationship, and use of avoidant-evasive coping strategies by husbands. The best predictive models of care giver depression were use of avoidant-evasive coping strategies and changes in husbands’ emotional health status related to care giving. / Doctor Of Philsophy (PhD)
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De sjukskrivna i rehabiliteringsprocessen : hinder och möjligheter / The persons on sick leave in the rehabilitation process : obstacles and possibilitiesGerner, Ulla January 2005 (has links)
<p>The background to the thesis is the high rate for sickness absence in Sweden since the end of the 1990s. In an international perspective, the Swedish sickness absence appears exceptionally high. This can appear paradoxical bearing in mind the high standard of living and the high average length of life in Sweden, and there is much to indicate that complex causal correlations are involved.</p><p>The overall aim of the thesis is to study and analyse the return to work or transition to disability pension, for persons on long-term sick leave from their own perspective. The focus of the thesis is the individual in a social context.</p><p>The theoretical frame of reference is within medical sociology and is about sickness concepts and models and on medicalisation. The concept of work capacity is also taken up based on the concepts of disability and impairment.</p><p>The empirical material consists of four studies. Two of these are qualitative interview studies with women. One of them (I) is about Greek women who have been granted Swedish disability pension. The aim of this study is to find explanations why such a large number of Greek women have become disability pensioners in Sweden. The analysis indicated some important factors: the doctors, the family and the social insurance system. The women had unclear psychosomatic complaints, which had been medicalised. The other qualitative study (IV) concerned women who after sick leave and rehabilitation succeeded in returning to work. It was seen to be strong and stubborn women who had to struggle to get back to working life. They had also been well taken care of in rehabilitation.</p><p>The other two studies (II and III) are quantitative, prospective cohort studies with persons on sick leave with unspecified back and neck complaints. One main aim of one study (III) was to investigate the importance of motivation for rehabilitation and return to work. Two specially designed forms were used. It was seen, among other things that the forecasts of the person on sick leave on return to work coincided quite well with a follow-up two years later. One important result was that those who had undergone rehabilitation measures had returned to work to a much lesser extent than those who had not.</p><p>Overall, the results showed the importance of listening to the individual and taking their own assessments of obstacles and possibilities in the rehabilitation process into consideration. The results in study III indicated that rehabilitation had not been sufficiently effective and in many cases did not lead to a return to work.</p>
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The Effects of Physical Activity on Adolescents Long- Term MemoryBäck, Fredrik January 2010 (has links)
<p>There is a body of research on the effect of physical activity oncognition in the old adult population. Less research areconducted on adolescents. The aim for this study is to find out ifadolescents long-term memory is affected by physical activity.144 pupils were asked to rate their physical activity each week.Thereafter their long- term memory was tested through tests onepisodic- and semantic memory. The results showed that thosewho are physically active more than 4 hours had a better scoreon part of the semantic test but no effect was found in theepisodic test. This result indicates that physical activity not onlyaffects working memory, as was shown by previous research butalso has an effect in parts of the semantic long-term memory.</p>
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The volunteer experience: predictors of success in the long term care Ombudsman roleDeHart, Kimberly N. 17 August 1999 (has links)
This study explored the influence of motivations on the volunteer experience. The relationship among motivations. volunteer satisfaction, acceptance and support of the organizational goals, and outcomes of success in the volunteer role (pattern of participation and ombudsman effectiveness) were explored using Multiple Linear Regression analyses. Motivational Systems Theory (Ford, 1992) was applied to the investigation of relationships among these variables. It was proposed that alignment between the individual volunteer's motivations and the organization's goals should predict higher levels of satisfaction, organizational commitment, and success.
Psychological aspects of the volunteer experience proved valuable to the explanation of certain indicators of success in the Ombudsman role. The rates of case reporting and the time devoted to the Ombudsman role seemed to be influenced by the importance of particular motivations toward volunteerism, the extent to which these motivations are fulfilled by involvement with the Ombudsman program, and the commitment expressed toward the organization.
Communal (offering) motivations were rated among the most important for the
majority of volunteers. However, satisfaction scores were higher for both agentic and
affiliation motivational factors than for the communal motivational factor. Overall,
Ombudsmen were least motivated by motivations characterized as agentic or self-oriented.
Volunteers with lower importance ratings for agentic motivations had
moderately higher reporting rates than did participants attributing less importance to
self-oriented motivations.
Volunteers expressed high levels of organizational commitment and overall satisfaction in the role. The more committed these participants were to the organization, the more likely they were to experience satisfaction in their roles, and the more likely they were to express high levels of importance for all factors of motivation in this model. A significant effect was found for the influence of organizational commitment on time commitment, case reporting, and the frequency of visits. Motivational Systems Theory was found to be a useful framework for analyzing the effects of personal characteristics and psychological aspects of the volunteer experience on success and satisfaction in the Ombudsman role. / Graduation date: 2000
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Modulation of dendritic excitabilityHamilton, Trevor 11 1900 (has links)
The computational ability of principal neurons and interneurons in the brain and their ability to work together in concert are thought to underlie higher order cognitive processes such as learning, memory, and attention. Dendrites play a very important role in neuronal information processing because they receive and integrate incoming input and can undergo experience-dependent changes that will alter the future output of the neuron.
Here, I have used whole-cell patch clamp recordings and fluorescent Ca2+-imaging to examine the modulation of dendritic excitability in principal neurons of the rat and human hippocampus and neocortex. First, I determined that dendrites of dentate granule cells of the hippocampus are tuned to high frequencies of both afferent input and backpropagating action potentials. Under these conditions they are also capable of generating regenerative dendritic activity that can propagate to the soma, which is prone to modulation. In particular, Neuropeptide Y (NPY) Y1 receptors can decrease frequency-dependent dendritic Ca2+ influx. Dopamine D1 receptors (D1Rs) have an opposite effect; they potentiate frequency-dependent dendritic excitability. These two neuromodulators also have an opposing effect on plasticity, with dopamine acting to induce, and NPY acting to inhibit long-term potentiation (LTP). Parallel observations of D1-induced LTP and an NPY-mediated decrease in dendritic excitability in rodents were complemented by findings in human dentate granule cells.
Second, I examined the role of NPY receptors on dendrites of layer 5 pyramidal neurons. In these neurons I found that NPY acts post-synaptically on distal dendrites via the Y1 receptor to inhibit frequency-dependent Ca2+-currents, similar to the findings in dentate granule cells. NPY also decreased regenerative Ca2+ currents caused by the appropriate pairing of pre- and post-synaptic input.
Together, these observations demonstrate that the role of NPY in the hippocampus and neocortex is not solely as an anti-epileptic agent. NPY release, likely to occur during high frequency oscillatory activity, can act locally to limit dendritic excitability, which can have a profound effect on plasticity. In the dentate gyrus, NPY can inhibit a D1R induced increased dendritic excitability and resultant changes in synaptic strength. These findings will further the understanding of dendritic information processing in the hippocampus and neocortex.
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Automatic Classification of Long Term Involuntary Spontaneous EMGWinslow, Jeffrey 10 April 2008 (has links)
Involuntary electromyographic (EMG) activity has been recorded in the thenar (thumb) muscles of spinal cord injured (SCI) subjects for only short time periods (minutes), but it is unknown if this motor unit activity is ongoing. Longer duration EMG recordings can investigate the physiological significance of this neuromuscular activity. Analysis of these data is complex and time consuming. Since no software is currently capable of classifying 24 hours of data at a single motor unit level, the goal of this research was to devise an algorithm to automatically classify motor unit potentials over 24-hours. Twenty-four-hour, 2-channel thenar muscle EMG recordings were obtained from four different SCI subjects with cervical level injuries using a data logging device with custom software. The automatic motor unit classification algorithm used to classify the 24-hour recordings was a procedure consisting of four stages that included segmentation, clustering, and motor unit template uniting. All individual potentials were then classified and any superimposed potentials were resolved into their constituent classes. Finally, the algorithm found the firing patterns for each of the stable motor unit classes. The classification algorithm performance was compared to the analysis of a human operator and assessed in 2 ways: Tracking global classes over the 24 hours and correctly classifying individual motor unit potentials as to belonging to particular global classes. The algorithm was able to track an average of 13 global classes in four 24-hour recordings with a mean accuracy of 92 %. It was also able to classify individual potentials with a mean accuracy of 86% over four recordings, greater than the inter-rater reliability of two human operators (79%). The activities of the motor units tracked by the algorithm ranged from tonic firing to sporadic activity. The algorithm could analyze 24 hours of data in 2-3 weeks, while a human operator was estimated to take more than 2 years. In conclusion, the motor unit classification algorithm accomplished its goal of automatically tracking motor unit classes over a 24-hour recording with high accuracy. The 24-hour classification method developed here could be applied towards classifying long term recordings of other biological signals.
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