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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.
81

Discovering relationships in genetic regulatory networks

Pal, Ranadip 15 November 2004 (has links)
The development of cDNA microarray technology has made it possible to simultaneously monitor the expression status of thousands of genes. A natural use for this vast amount of information would be to try and figure out inter-gene relationships by studying the gene expression patterns across different experimental conditions and to build Gene Regulatory Networks from these data. In this thesis, we study some of the issues involved in Genetic Regulatory Networks. One of them is to discover and elucidate multivariate logical predictive relations among gene expressions and to demonstrate how these logical relations based on coarse quantization closely reflect corresponding relations in the continuous data. The other issue involves construction of synthetic Probabilistic Boolean Networks with particular attractor structures. These synthetic networks help in testing of various algorithms like Bayesian Connectivity based approach for design of Probabilistic Boolean Networks.
82

Molecular cloning and characterization of important stress and redox regulatory genes from Hydra vulgaris

Dash, Bhagirathi 25 April 2007 (has links)
In this research, important stress and redox regulatory genes present in Hydra vulgaris were isolated and characterized to facilitate our understanding of the evolution and mechanisms of stress response. H. vulgaris heat shock protein 70 (HvHSP70), extracellular copper zinc superoxide dismutase (HvECCuZnSOD), manganese superoxide dismutase (HvMnSOD), phospholipid peroxidase glutathione peroxidase (HvPHGPx) and monofunctional catalase (HvCatalase) were cloned and characterized with regard to stress response, phylogeny and molecular structure. The HSP70 gene isolated from H. vulgaris encodes a polypeptide of 650 amino acids (Mw=710,037) and is interrupted by three intron sequences. The 5' non-coding region of the HvHSP70 possessed the canonical heat shock elements. Phylogenetically HvHSP70 formed a distinct lineage. A molecular model generated for the N-terminal fragment of the HvHSP70 displayed the heat shock protein fold and domains of phosphotransferases. The EC-CuZnSOD cDNA isolated from H. vulgaris encodes a protein of 189 amino acids (Mw=20959.73); the first 19 amino acids constitute the presumed signal peptide. Phylogenetically HvEC-CuZnSOD is grouped with ECCuZnSODs from several organisms. A molecular model generated for the HvEC-CuZnSOD displayed the CuZnSOD (beta)-barrel fold. The MnSOD cDNA isolated from H. vulgaris encodes a protein of 219 amino acids (Mw=24348.75); the first 21 amino acids constitute the presumed mitochondria-targeting signal peptide. Phylogenetically HvMnSOD is clustered with mollusk and crustacean MnSODs. A molecular model generated for the HvMnSOD displayed the N-terminal long alpha antiparallel hairpin and the Cterminal mixed alpha/beta fold characteristic of MnSODs. The PHGPx gene isolated from H. vulgaris encodes a polypeptide of 168 amino acids (Mw=18746.51) including a TGA-encoded selenocysteine at residue 44 and lacks any intron. Phylogenetically HvPHGPx is grouped with PHGPxs from several organisms. A molecular model generated for the HvPHGPx displayed the thioredoxin fold. The 3'-end of a cDNA sequence encoding for 168 amino acids of the Cterminal end of a catalase was isolated from H. vulgaris. Phylogenetically HvCatalase is grouped with heme-containing monofunctional catalases. Hydrae exposed to thermal, starvation, oxidative and metal stress responded by regulating respective mRNA transcriptions suggesting that these genes are involved in stress and (anti)oxidative processes and may have potential as molecular biomarkers for assessing aquatic environment quality.
83

Is the coal industry worth protecting? an examination of the effects of competing advocacy coalitions on implementation of the Surface Mining Control and Reclamation Act (SMCRA) of 1977

Pennington, Michael Sean 10 October 2008 (has links)
Harold Lasswell (1936) defined politics as the exploration of "who gets what, when, and how." As such, one of the central concerns of democratic governance is the role that affected interests play not only in politics, but in the implementation of adopted policies as well. In this dissertation, I use both comparative method case studies, as well as pooled-time series statistical techniques, to examine the effects of political, economic and market forces, and competition between the affected interests on implementation of the Surface Mining Control and Reclamation Act of 1977. The findings of this, as well as previous, research shows that state-level implementing agencies have some discretion in enforcement activities; however, closer examination shows that this discretion is rarely used. This lack of use of regulatory discretion by the state-level implementing agencies suggests that in most states, there is either sufficient competition between the affected interests to neutralize the excessive use of discretion in enforcement activity, or that there is insufficient pressure placed on the implementing agencies by the affected interests to warrant the use of discretion.
84

A Study of The Relationship between Spiritual Leadership and Change Commitment: Mediated by Regulatory Focus

Tsao, Yung-peng 26 June 2009 (has links)
A causal theory of spiritual leadership taps into the fundamental needs of both leader (vision, hope/ faith, altruistic love) and follower for spiritual survival (calling/meaning, membership). The definition of spiritual leadership is to comprise the values, attitudes, and behaviors that are necessary to intrinsically motivate one¡¦s self and others so that they have a sense of spiritual survival through calling and membership, and to improve employees¡¦ organization commitment and productivity. In addition, change commitment which is one of the positive attitudes toward organizational change, could promote the success of organizational change. The relationship between spiritual leadership and change commitment will be discussed. Furthermore, employees¡¦ emotional experiences might influence the work attitudes and behaviors. Regulatory focus theory which includes promotion focus and prevention focus, will focus on the one¡¦ emotional content, magnitude and the further effect. It¡¦s helpful to describe the relationship between emotional experiences and work attitudes and behaviors. As a result, the mediating mechanism of regulatory focus between spiritual leadership and commitment will be discussed. Use LISREL to analyze the survey data from 369 employees. Following are the results: 1. There is a positive relationship among spiritual leadership, calling/ meaning and membership, and change commitment. And calling/ meaning and membership are the mediators in the relationship between spiritual leadership and change commitment. 2. There is a positive relationship among spiritual leadership, promotion focus and change commitment. And promotion focus is the mediator in the relationship between spiritual leadership and change commitment. Although spiritual leadership positively affects prevention focus, however, prevention focus will not influence change commitment. 3. The differences of respondents¡¦ profiles will make effects on spiritual leadership, calling/meaning, membership, regulatory focus and change commitment.
85

The Perception of Emergency Department Physicians Regarding Economic and Regulatory Factors Impacting Management of Drug Seeking Patients

Kelley, Sharon Susanne 01 January 2013 (has links)
Abstract Physicians in the emergency department (ED) are facing a number of unique challenges in the currently changing healthcare and economic climates. Dramatic increases in ED patient volumes have been noted nationwide with visits related to prescription opioid abuse and misuse alone having increased by 111% between 2004 and 2008. Ironically, several challenges ED physicians are facing arise from regulatory and economic initiatives which were originally designed for the protection of patients. Regulatory requirements to address pain as the fifth vital sign, along with entities utilizing patient satisfaction based reimbursement, have inadvertently created an environment conducive to exploitation by the prescription opioid abuser. A literature review revealed an informational gap with regard to the impact economic and regulatory factors exert on the management of patients, exhibiting drug seeking behavior, by ED physicians. The lack of available information is the basis for this original research. A descriptive, cross-sectional, non-experimental study was conducted over a two month period (October - November, 2013) to elicit opinions of ED physicians regarding the management of opioid seeking patients. Respondents were asked to include opinions on factors perceived to impact treatment of this patient population. Of the ED physicians surveyed, 71% reported a perceived pressure to prescribe opioids to avoid administrative and regulatory criticism and 98% perceive patient satisfaction scores as being too highly emphasized by reimbursement entities as a means of evaluating healthcare quality. Rising patient volumes and changes in the healthcare climate were also cited as factors impacting management practices when treating patients exhibiting drug seeking behavior. Emergency department physicians have a unique role in providing unrestricted access of care for the public. This role, in conjunction with the aforementioned concerns, has served to create an environment conducive to the potentiation of prescription opioid misuse and abuse.
86

An empirical evaluation on how regulatory and market factors affect title insurance charges

Zou, Beibei 24 September 2013 (has links)
The objective of this dissertation is to evaluate how regulatory and market factors affect title insurance charges in different states. As substantial components of home purchase closing costs, title insurance charges have been controversial for decades, and both practitioners and analysts have pointed out apparent variations in title insurance charges among states. Although existing studies have suggested a set of regulatory and market factors as explanations for these among-state variations, empirical evaluations are limited. To fill in this gap, this dissertation empirically assesses whether these factors influence title insurance charges. The research outcomes of these dissertation indicate that after taking into account market factors such as services included in title insurance charges, title-related losses, property values, state populations, home sale volumes, housing prices, and income levels, regulation styles can still partially explain the title insurance charge variations in different states. In particular, states with promulgation regulation can have a higher average title insurance charge than states allowing free competition. This dissertation also tests whether regulation affects title insurance charges by influencing competition in the market and whether regulators' characteristics are related to the effect of regulation on charges. The test results imply that appointed commissioners can be associated with a higher average title insurance charge than elected commissioners. This dissertation provides insights into the title insurance regulatory reform in different states. More broadly, one methodology (multiple model for change) used in this dissertation simultaneously assesses regulation's over-time and state-by-state effects on title insurance charges, which contributes to the development of regulation evaluation methods. The outcomes of this dissertation can also provide empirical evidence to the theoretical debate of regulation versus competition. / text
87

Stability analysis of uncertain genetic regulatory newtworks

Li, Jiewei., 李劼伟. January 2013 (has links)
Genetic regulatory network (GRN) is a fundamental research area in systems biology. This thesis studies the stability of a class of GRN models. First, a condition is proposed to ensure the robust stability of uncertain GRNs with SUM regulatory functions. It is assumed that the uncertainties are in the form of a parameter vector that determines the coefficients of the model via given functions. Then, the global asymptotic stability conditions of uncertain GRNs affected by disturbances and time delays are further explored. The conditions are obtained by solving a convex optimization problem by exploring the sum of squares (SOS) of matrix polynomials and by introducing polynomially parameter-dependent Lyapunov-Krasovskii functionals (LKFs). Moreover, based on the uncertain GRNs with guaranteed disturbance attenuation, it is shown that estimates of the sought stable uncertainty sets can be obtained through a recursive strategy based on parameter-dependent Lyapunov functions and the SOS. Second, the stability conditions of GRNs described by piecewise models are considered. Depending on whether the state partitions and mode transitions are known or unknown as priori, the proposed networks are divided into two categories, i.e., switched GRNs and hybrid GRNs. It is shown that, by using common polynomial Lyapunov functions and piecewise polynomial Lyapunov functions, two conditions are established to ensure the global asymptotic stability for switched and hybrid GRNs, respectively. In addition, it is shown that, by using the SOS techniques, stability conditions in the form of LMIs for both models can be obtained. Third, the multi-stability of uncertain GRNs with multivariable regulation functions is investigated. It is shown that, by using the Lyapunov functional method and LMI technology, a criterion is established to ensure the robust asymptotical stability of the uncertain GRNs, and such condition can be extended to deal with the multi-stability problem. Moreover, it is shown that by using the square matrix representation (SMR) and by adopting polynomially parameter-dependent Lyapunov functions, a condition in the form of LMIs for robust stability for all admissible uncertainties can be obtained. Examples with synthetic and real biological models are presented in each section to illustrate the applicability and effectiveness of the theoretical results. / published_or_final_version / Electrical and Electronic Engineering / Doctoral / Doctor of Philosophy
88

The effect of sewage effluent on trace metal speciation : implications for the biotic ligand model approach

Constantino, Carlos January 2013 (has links)
This research examined the suitability of the biotic ligand model (BLM) approach for assessing environmental risk in surface waters consisting substantially of treated sewage effluent, and the implications of its use within a compliance-based regulatory framework aimed at controlling discharges of metals into the aquatic environment. The results from a series of Daphnia magna acute copper toxicity assays conducted in an undiluted sewage effluent medium demonstrated that BLMs could predict an acute copper toxicity endpoint with suitable accuracy. This finding contributes further support for the use of BLMs for assessing risk and compliance, even in effluent impacted waters. Additional studies, however, also demonstrated that effluent derived organic matter contained a greater concentration of metal complexing ligands per milligram of dissolved organic carbon than organic matter derived from natural sources. This indicates that effluent derived organic matter offers greater protection against the potentially adverse effects from metals than the protection offered by organic matter derived from natural sources. These studies also demonstrated that improvements in the accuracy of BLM forecasts were achievable by taking these differences into account which, from a regulatory perspective, is also desirable since this enhances the environmental relevance of compliance criteria. These findings therefore justify that consideration for the influence of site-specific metal complexation characteristics should included as part of the regulatory framework within which BLMs will be applied. The implication of the BLM approach for Severn Trent Water Limited is that, as currently proposed, the approach will require a reduction in the concentration of copper in the effluent discharges for a small number of wastewater treatment works (9), whereas for zinc, concentration reductions may be required for numerous treatment works (126).
89

An investigation of the relationship between levels of uncertainty, illness representations, coping strategies, psychological and physical functioning in chronic illness

Homewood, Helen January 2001 (has links)
Objectives: Theoretical models have helped conceptualise how individuals appraise and make sense of chronic illness and its psychological impact. Little attention has been given to the impact of uncertainty on this process. The objective was to investigate the relationship between levels of uncertainty, illness representations, coping, psychological and physical functioning in two chronic illnesses. The Self-Regulatory Model (SRM, Leventhal, Meyer & Nerenz, 1980) was used as a theoretical framework. Design: A cross-sectional design was used. It was hypothesised that a clear medical diagnosis would reduce levels of uncertainty and increase illness representations regarding control of symptoms. It was also hypothesised that high levels of uncertainty would independently predict increased psychological distress. Method: Patients suffering from chronic spinal pain and rheumatoid arthritis were recruited from local clinical departments. The levels of uncertainty, illness representations, coping strategies, mood and physical functioning of 85 participants were assessed using standardised questionnaires. Results: Chronic pain patients were found to have greater levels of uncertainty and psychological distress than rheumatoid arthritis patients. Rheumatoid arthritis patients had stronger beliefs about control of their condition. Uncertainty was not found to be a significant independent predictor of anxiety or depression. However, there appeared to be a degree of overlap between the variables of uncertainty and control beliefs. Conclusions: The findings highlight a complex relationship between the aspects of the SRM and uncertainty, with many components impacting on each other. Although levels of uncertainty were not found to be predictive of psychological distress, it is an area that warrants further investigation in order to understand how patients manage uncertainty. Within a clinical setting, issues of uncertainty should be addressed at all levels of care, maximising the patient's control beliefs, reducing the impact of uncertainty on their cognitive, emotional and physical functioning.
90

High speed rail : a study of international best practices and identification of opportunities in the U.S.

Rutzen, Beatriz 20 December 2010 (has links)
In the United States, passenger rail has always been less competitive than in other parts of the world due to a number of factors. Many argue that in order for a passenger rail network to be successful major changes in service improvement have to be implemented to make it more desirable to the user. High-speed rail can offer such service improvement. With the current administration’s allocation of $8 billion in its stimulus package for the development of high-speed rail corridors and a number of regions being interested in venturing into such projects it is important that we understand the factors and regulatory structure that needs to exist in order for passenger railroad to be successful. This study aims to review how foreign countries have developed and their railroad systems to identify key factors that have contributed to its successful implementation. An evaluation of the factors, such as organization structure, operation, administration, development and type of funding, that are common to each of these projects will used as performance measures to identify potential locations and opportunities for high speed rail projects in the U.S. Southwest region. / text

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