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A Multi-level Model Examining the Effects of Unit-level Culture on Abusive SupervisionSiegel, Jessica Lynn January 2011 (has links)
This study examines the effects of unit-level culture on abusive supervision. Utilizing Baumeister and colleagues' (2000) self-regulatory resource depletion model as an explanatory framework, I argue that aggressive unit-level culture will increase the incidence of abusive supervision, whereas people- and team-oriented unit-level cultures will decrease the incidence of abusive supervision. In line with these arguments, I then examine the degree to which those effects are mediated by ego depletion. In sum, I argue that aggressive unit-level culture will increase, while people- and team-oriented cultures will reduce, the amount of supervisor ego depletion, which then increases the incidence of abusive supervision. Using Hobfoll et al.'s (1990) Social Support Resource Theory, I further argue that the relationship between unit-level culture and ego depletion is moderated by supervisor home social support. I tested my model using a sample of 340 nurses and 52 nursing directors working in a large hospital system in the Southwestern United States. I was unable to demonstrate support for my model as hypothesized. However, I am able to contribute to the literature concerning antecedents to abusive supervision by showing that alternative conceptualization of culture impact abusive supervision. Further, I show that aggressive norms mediate the relationship between aggressive culture and abusive supervision. I also contribute to the literature examining resource depletion in the workplace by demonstrating the buffering role of supervisor home social support on ego depletion. Implications and future directions are discussed.
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Decoding the Language of Hypoglossal Motor ControlLaine, Christopher January 2011 (has links)
To effect movement, the central nervous system must appropriately coordinate the activities of pools of motoneurons (MNs), the cells which control muscle fibers. Sources of neural drive are often distributed to many MNs of a pool, and thus can synchronize the activities of targeted MNs. In this thesis, synchronization among MNs is used to investigate the strength, temporal progression, and anatomical distribution of neural drive to the hypoglossal motor nucleus (HMN), which controls muscles of the tongue. The HMN is an ideal target for such an investigation because it processes a host of functionally diverse inputs, such as those related to breathing, speaking, and swallowing. Study 1 characterizes motor unit (MU) synchronization within and across bellies of the human genioglossus (GG) muscle when MUs are activated by cortical drive (during voluntary tongue protrusion) or by automatic, brainstem-mediated drive (during rest breathing). We show that voluntary tongue protrusion synchronizes MU spike timing and firing rates within but not across bellies of the GG, whereas during rest breathing, MU firing rates are moderately synchronized both within and across muscle bellies. Study 2 documents respiratory-related synchronization of MU activities in muscles of the tongue and respiratory pump using an anesthetized rat model. The results of this study indicate that upper airway and respiratory pump MN pools share a low frequency respiratory-related drive, but that higher frequency (>8 Hz) synchronization is strongest in MU pairs of the chest-wall. Finally, Study 3 examines the potential for GG multi-unit and single MU activities to be entrained by cortical input. We show that during voluntary tongue protrusion, cortical oscillations in the 15-40 Hz range weakly synchronize MU population activity, and that EEG oscillations in this range intermittently influence the spike timing of individual GG MUs. These studies are the first to characterize MU synchronization by different sources of neural input to the HMN and establish a broad foundation for further investigation of hypoglossal motor control.
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Experience-Dependent Network Modification in the Medial Temporal LobeThome, Alexander January 2012 (has links)
Theoretical models of information storage in the brain have suggested that neurons may undergo an experience-dependent tuning or sharpening of their representations in order to maximize the amount of information that can be stored. Changes in the tuning profiles of neurons have been demonstrated to occur when animals must learn perceptual discriminations, however, whether similar changes occur in the absence of behavioral demands is unclear. To address these questions, the activity of simultaneously recorded medial temporal lobe (MTL) neurons was studied in relation to a passive visual recognition memory task. The structure of this task was such that it allowed for a comparison between novelty related responses as well as tuning properties of individual neurons. A total of 565 well isolated single neurons were recorded. The first contribution of this dissertation is the finding of a dissociation between different medial temporal lobe regions such that neurons in temporal area F (TF), but not perirhinal cortex (PRC) or the hippocampus, show an experience-dependent change in their stimulus selectivity. This finding indicates that tuning of stimulus representations may be an effective mechanism for maximizing information storage in some brain regions. The absence of stimulus tuning in higher level association regions (i.e. TF and PRC) suggests that tuning in these regions may be disadvantageous due to the need to construct unified representations across sensory modalities. A complimentary question to the question of network storage capacity is how networks avoid saturation in the connections between neurons. The second contribution of this dissertation is the finding that there exists a decrease in the magnitude of the short time scale correlations between pairs of neurons; suggesting that networks reduce the number of connections between neurons as a stimulus becomes familiar. Gamma oscillations have been proposed to be the mechanism by which groups of neurons coordinate their activity. However, network coordination has only been indirectly measured. The final contribution of this dissertation is the finding that the magnitude of gamma oscillations is strongly correlated with enhanced magnitude of correlations between neurons.
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Association between Use of a Specialized Diagnostic Assessment Unit and the Diagnostic Interval in Ontario Breast Cancer PatientsJiang, Li 18 November 2013 (has links)
Background: The amount of time that it takes to get a breast cancer diagnosis is very important to patients. The Ontario diagnostic assessment unit (DAU) is designed to improve the quality and timeliness of care during a breast cancer diagnosis. This study described and examined the association between the length of the diagnostic interval and DAU use in Ontario, Canada. Methods: This was a retrospective cohort study among all breast cancer patients diagnosed between Jan 1st, 2011 and Dec 31st, 2011 in Ontario, Canada. DAU use and diagnostic intervals were described. The association between DAU use and the diagnostic interval was examined separately in a cohort of 2499 screen-detected patients and a cohort of 4381 symptomatic patients. Study data sources included administrative databases available at the Institute for Clinical Evaluative Sciences (ICES) and Cancer Care Ontario (CCO). The diagnostic interval was defined as the time from the index contact to the cancer diagnosis. DAU use was determined based on the payment record within the organized screening program as well as the hospital where patients were diagnosed. Multivariate median regressions were used to control for possible confounders. Results: On average, Ontario breast cancer patients waited 4.6 weeks to be diagnosed. Forty-eight percent were diagnosed in a DAU and 52% were diagnosed in the usual care route. In screen-detected patients, DAUs had a higher rate in meeting national timeliness targets compared to usual care (79.1% vs. 70.2%, p<0.001). DAU use was significantly associated with an 8.3-day decrease in the time to diagnosis (95% CI: 6.5-10.2) after controlling for potential confounders. In symptomatic patients, DAUs also had a higher rate in achieving the Canadian timeliness targets compare to usual care (71.7% vs. 58.1%, p<0.001). DAUs significantly reduced the time to diagnosis by 10 days (95% CI: 7.8-11.9) after controlling for possible confounders. Conclusions: We observed considerable variation in breast cancer diagnostic intervals and DAU use in Ontario. Use of Ontario DAUs was associated with improved diagnostic timeliness for breast cancer patients. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2013-11-18 13:19:03.231
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A mixed method investigation into the psychological well-being of individuals who have suffered from Guillain-Barré SyndromeHarrison, Catherine Victoria January 2010 (has links)
The needs of patients who are nursed on the ICU are becoming more widely recognised and services are beginning to reflect this. However there is little research into how patients who have suffered from a severe and progressive muscular paralysis called Guillain-Barré Syndrome (GBS) experience the disease and subsequent hospitalisation. The purpose of this study was to explore how these patients experience the different aspects of the illness, including an extended period of paralysis and treatment on an ICU. This is intended to expand upon the limited research in this area and identify how the findings can inform clinical practice and future studies. Method: A systematic literature search identified research in relation to the experiences of individuals who had GBS which was utilised to form the basis of the understanding for this study. Very little systematic research has looked at individuals‟ experiences of Guillain-Barré Syndrome whilst ill and their subsequent recovery. A mixed methods study was carried out with the aim of adding to this research. Interpretative Phenomenological Analysis was selected as the method of analysis for Study 1, which involved interviews with seven participants who had experienced GBS severe enough to need treatment on an ICU. This then enabled quantitative questionnaires to be disseminated which asked about individuals‟ levels of anxiety, depression and Post Traumatic Stress symptomatology both retrospectively and following recovery in Study 2. Results: Study1 found that participants experienced GBS as either a slow and frustrating, or as a rapid and scary onset. The main themes that were developed included: the paralysis being viewed as multiple losses, frustration, difficulties associated with communication loss, vulnerability and frightening hallucinations. Study 2 utilised non-parametric analyses of the data and found that participants experienced high levels of anxiety and depression at the onset of GBS and that some continued to experience anxiety, depression and post traumatic symptoms after recovery from GBS. Generally the profile suggests predominantly anxiety problems during the acute onset phase and then predominantly depression at the time of follow-up. Aspects of post traumatic stress were positively correlated with duration of mechanical ventilation which in turn was related to duration of paralysis. This challenged the hypothesis that GBS patients habituate to the experience of paralysis. Conclusion: For some individuals, GBS was experienced as a frightening event, but one that they could draw positive things from. However, for others, GBS was experienced as a traumatic event and some of these people continued to exhibit signs of psychological distress even after recovery. It remains important for staff to feel able to speak about distressing situations with their patients and to signpost them to other psychological services if appropriate.
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Comparison of poractant versus beractant in the treatment of respiratory distress syndrome in premature neonates in a tertiary academic medical centerJorgensen, Ashley January 2012 (has links)
Class of 2012 Abstract / Specific Aims: The objective of this study is to evaluate and compare clinical outcomes and economic impact involved with the use of beractant (B) compared to poractant (P) for the treatment of respiratory distress syndrome (RDS) in premature neonates admitted to a neonatal intensive care unit.
Methods: Patients were included if they were less than 35 weeks gestational age at birth, survived at least 48 hours, and admitted to the neonatal intensive care unit and treated with P or B for RDS. The primary outcome of this study is the change in the fraction of inspired oxygen (FiO2) over the first 48 hours after surfactant administration. Secondary outcomes were the change in oxygen saturation, time spent on mechanical ventilation and continuous positive airway pressure (CPAP), complication occurrence and mortality of the neonates.
Main Results: There were a total of 40 neonates whose charts were reviewed (n= 13 and n=27 in the P and B groups respectively). The mean gestational age of the neonates were 29.2+/-2.9 and 28.8+/-2.9 weeks in the P and B groups respectively. The FiO2 was found to not be lower between the P and B groups (35.5+/-22.2 and 42.4+/-24.2, respectively; p=0.379), as well as the O2 saturation (94.6+/-4.6 and 92.3+/-6.1; p=0.194). Significance was also not found for the other clinical or economic outcomes assessed in this study.
Conclusions: There was not a significant difference between poractant and beractant in FiO2, O2 saturation, or in the other clinical outcomes evaluated in this study.
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A Study of Proposed Mandatory Unit Pricing in the Dallas-Fort Worth AreaBarry, Thomas E., 1943- 08 1900 (has links)
The purpose of this research was to compile data from both the consumer and business sectors of the economy in an attempt to determine whether unit price information given to the consumer by a mandatory unit price bill would be justified .
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DOMESTIC VIOLENCE: CONTEMPORARY INTERVENTIONS AND THE RISE OF SPECIALIZED DOMESTIC VIOLENCE UNITSAnderson, Laura E 01 January 2014 (has links)
This dissertation examines recidivism for domestic violence offenders under both traditional probation and specialized probation conditions. This research compares recidivism at a traditional probation locality (Riverside Criminal Justice Services) and a specialized domestic violence unit (Chesterfield Community Corrections Services) in order to determine the nature of recidivism at both localities. In addition, the research aims to identify individual risk factors which are statistically associated with recidivism. The research is based on secondary data and draws on offender criminal records generated by the Virginia State Police, as well the extraction of information from probation files at both localities. The multivariate models indicate that a higher degree of recidivism occurs at the specialized domestic violence unit, and that the experimental locality, along with a younger age, are consistently statistically significant predictors for recidivism. Less consistent but still statistically significant risk factors included positive drug tests, higher supervision levels, and unsuccessful probation completion. The implications of these findings, as well as policy recommendations and directions for future research are fully discussed.
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Genetic programming and cellular automata for fast flood modelling on multi-core CPU and many-core GPU computersGibson, Michael John January 2015 (has links)
Many complex systems in nature are governed by simple local interactions, although a number are also described by global interactions. For example, within the field of hydraulics the Navier-Stokes equations describe free-surface water flow, through means of the global preservation of water volume, momentum and energy. However, solving such partial differential equations (PDEs) is computationally expensive when applied to large 2D flow problems. An alternative which reduces the computational complexity, is to use a local derivative to approximate the PDEs, such as finite difference methods, or Cellular Automata (CA). The high speed processing of such simulations is important to modern scientific investigation especially within urban flood modelling, as urban expansion continues to increase the number of impervious areas that need to be modelled. Large numbers of model runs or large spatial or temporal resolution simulations are required in order to investigate, for example, climate change, early warning systems, and sewer design optimisation. The recent introduction of the Graphics Processor Unit (GPU) as a general purpose computing device (General Purpose Graphical Processor Unit, GPGPU) allows this hardware to be used for the accelerated processing of such locally driven simulations. A novel CA transformation for use with GPUs is proposed here to make maximum use of the GPU hardware. CA models are defined by the local state transition rules, which are used in every cell in parallel, and provide an excellent platform for a comparative study of possible alternative state transition rules. Writing local state transition rules for CA systems is a difficult task for humans due to the number and complexity of possible interactions, and is known as the ‘inverse problem’ for CA. Therefore, the use of Genetic Programming (GP) algorithms for the automatic development of state transition rules from example data is also investigated in this thesis. GP is investigated as it is capable of searching the intractably large areas of possible state transition rules, and producing near optimal solutions. However, such population-based optimisation algorithms are limited by the cost of many repeated evaluations of the fitness function, which in this case requires the comparison of a CA simulation to given target data. Therefore, the use of GPGPU hardware for the accelerated learning of local rules is also developed. Speed-up factors of up to 50 times over serial Central Processing Unit (CPU) processing are achieved on simple CA, up to 5-10 times speedup over the fully parallel CPU for the learning of urban flood modelling rules. Furthermore, it is shown GP can generate rules which perform competitively when compared with human formulated rules. This is achieved with generalisation to unseen terrains using similar input conditions and different spatial/temporal resolutions in this important application domain.
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Vlastnictví bytů / Ownership of flatsStehlík, Václav January 2011 (has links)
Flat ownership The theme of this thesis is flat ownership. The author has chosen this theme because it is very current and from the legal point of view also very interesting issue, which affects the major part of the population of the Czech Republic. The main objective of this work is to analyze the Institute's flat ownership in terms of the Flat Ownership Act. Furthermore, to highlight some problematic points in the regulation of housing ownership, to comment and suggest possible solutions with regard to case law and opinions of authors specializing in issues of housing ownership. This work consists of eight chapters. The first chapter deals with basic theoretical concepts of flat property, important for understanding the specific nature of the Institute's flat property. Such basics also may serve as a guide for policymakers in the design of legislation on housing. Then continues the second chapter, which talks about the concept of law based on flat ownership, its applicability and relationship to the Civil Code and other regulations. The third chapter focuses on the definition of specific terms related to the issue of flat property, such as: building, section, house, unit, flat, flat under construction, floor area of a flat, common space in building and land. The following fourth chapter is...
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