Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 51-58). Also available on the Internet.

ABSTRACT Insulin Dynamic Measures and Weight Change By Noreen Kloc B.S. Computer Information Technology, Purdue University December 7, 2015 INTRODUCTION: Weight gain and obesity are risk factors for insulin resistance that can lead to type 2 diabetes and cardiovascular disease; however, there is a complicated interplay between insulin sensitivity (SI), fasting insulin, acute insulin response (AIR), and disposition index (DI) and the relationship of these dynamic measures with weight change is not well understood. AIM: The aim of this study was to investigate the relationships between insulin dynamic measures, SI, fasting insulin, AIR, and DI, with weight change during a 5-years follow-up period in the multi-ethnic cohort of the Insulin Resistance Atherosclerosis Study (IRAS). METHODS: Data on 879 men and women of Hispanic, non-Hispanic White, and African-American race/ethnicity aged 40-69 years were obtained at baseline (1992-1994) and at 5 year follow-up. Crude associations between the insulin dynamic measures and weight change were evaluated using Kruskal-Wallis test and the relationships between log-transformed insulin-related variables were examined using Spearman rank-order analysis. Multivariate regression models evaluated associations of interest adjusted for age, sex, ethnicity, and diabetes status in a time-dependent manner using mixed models. RESULTS: Insulin sensitivity SI inversely coevolves with weight, i.e. greater weight is predicted by lower SI at any time point. To answer the question whether SI is the cause or a consequence of weight change, we examined the associations with the baseline values and a change in SI. In this model, both the baseline SI and change in SI were inversely correlated with weight gain. A similar approach showed that baseline values and change in fasting insulin were directly associated with weight gain. Weight change over time was associated with AIR, i.e. increases in AIR and greater AIR at baseline predicted weight gain. We did not find strong relationships between DI and weight change. DISCUSSION: These results suggest that insulin sensitivity and insulin secretion can modulate weight in a non-diabetic population.

Environmental targets set by governments around the world are leading to high penetrations of small to medium-scale renewable distributed generation (DG). High penetration of DG in distribution networks, however, can result in voltage and thermal issues among other technical problems. The traditional 'Fit & Forget' approach that refers to the passive use of assets with limited or no control, in the context of distribution network planning, is used to meet maximum demand or generation requirements. However, to ensure that more renewable generation is cost-effectively connected to distribution networks, it is imperative to adopt a more active control of network elements and participants. The active control of future distribution networks requires understanding the corresponding dependencies between voltage magnitudes and DG active/reactive power outputs to mitigate voltage issues. One classical method to calculate these dependencies is to use sensitivity approaches such as those based on the Jacobian matrix. However, during operation, updating the Jacobian matrix requires the network to be fully observable making it unfeasible for decentralized control approaches. Therefore, it is critical to develop a sensitivity approach only requiring local real-time information. This thesis proposes a novel approach to produce voltage sensitivity coefficients using the surface fitting technique based solely on knowledge of network characteristics and, therefore, no remote monitoring is required. To assess the performance of the proposed voltage sensitivity approach, a decentralized (local) voltage control algorithm that simultaneously caters for both the active and reactive power outputs of a single DG plant is adopted. Comparisons with classical sensitivity approaches are carried out using the 16-bus UK GDS test network, 1-min resolution demand and wind generation data. Persistence forecasting (i.e., assuming no changes in demand and wind in a short time period) is considered in this case. The lower Mean Squared Error (MSE) shows that the coefficients of the proposed sensitivity approach are close to those of the Jacobian matrix and better than the perturb-and-observe approach. In the context of voltage management, results highlight that the proposed sensitivity approach is more effective than the Jacobian matrix inverse and perturb-and-observe, resulting in better voltage compliance and energy harvesting (better capacity factor). It should be highlighted that this performance is achieved without the need of full network observability. Furthermore, to cater for the more realistic and complex case of multiple DG plants, this thesis proposes a time-delay based decentralized control algorithm. A comparison with an ideal AC Optimal Power Flow (OPF) is carried out using the same 16-bus UK GDS network but with seven DG plants. The results demonstrate that the proposed sensitivity approach and time delays are very effective when compared to the AC OPF. This, in turn, proves that the combined use of the proposed voltage sensitivity approach and the decentralized controller is an implementable, cost-effective solution to manage DG plants in distribution networks without the need of further communication infrastructure. Finally, a decentralized DG control logic with the capability of using wind forecasting techniques is proposed to tackle the unpredictable nature of wind power. In this work, a time-series based forecasting technique is incorporated to the proposed decentralized controller. The results confirm that the use of more advanced forecasting technique can further improve the management of renewable DG plants.

abstract: Protein folding is essential in all cells, and misfolded proteins cause many diseases. In the Gram-negative bacterium Escherichia coli, protein folding must be carefully controlled during envelope biogenesis to maintain an effective permeability barrier between the cell and its environment. This study explores the relationship between envelope biogenesis and cell stress, and the return to homeostasis during envelope stress. A major player in envelope biogenesis and stress response is the periplasmic protease DegP. Work presented here explores the growth phenotypes of cells lacking degP, including temperature sensitivity and lowered cell viability. Intriguingly, these cells also accumulate novel cytosolic proteins in their envelope not present in wild-type. Association of novel proteins was found to be growth time- and temperature-dependent, and was reversible, suggesting a dynamic nature of the envelope stress response. Two-dimensional gel electrophoresis of envelopes followed by mass spectrometry identified numerous cytoplasmic proteins, including the elongation factor/chaperone TufA, illuminating a novel cytoplasmic response to envelope stress. A suppressor of temperature sensitivity was characterized which corrects the defect caused by the lack of degP. Through random Tn10 insertion analysis, aribitrarily-primed polymerase chain reaction and three-factor cross, the suppressor was identified as a novel duplication-truncation of rpoE, here called rpoE'. rpoE' serves to subtly increase RpoE levels in the cell, resulting in a slight elevation of the SigmaE stress response. It does so without significantly affecting steady-state levels of outer membrane proteins, but rather by increasing proteolysis in the envelope independently of DegP. A multicopy suppressor of temperature sensitivity in strains lacking degP and expressing mutant OmpC proteins, yfgC, was characterized. Bioinformatics suggests that YfgC is a metalloprotease, and mutation of conserved domains resulted in mislocalization of the protein. yfgC-null mutants displayed additive antibiotic sensitivity and growth defects when combined with null mutation in another periplasmic chaperone, surA, suggesting that the two act in separate pathways during envelope biogenesis. Overexpression of YfgC6his altered steady-state levels of mutant OmpC in the envelope, showing a direct relationship between it and a major constituent of the envelope. Curiously, purified YfgC6his showed an increased propensity for crosslinking in mutant, but not in a wild-type, OmpC background. / Dissertation/Thesis / Ph.D. Microbiology 2010

This study investigates sources of steady state computational uncertainty in an effective heat transfer coefficient (HTC) within a non-reacting bubbling fluidized bed with immersed horizontal heat-conducting tubes. The methodical evaluation of this variation, or Uncertainty Quantification (UQ), is a critical step in the experimental analysis process, and is particularly important when the values of input physical parameters are unknown or experimental data is sparse. While the concept applies broadly to all studies, this application investigates a 2D unit cell analogue of a bubbling fluidized bed designed for large-scale carbon capture applications. Without adequate characterization of simulation uncertainties in the HTC, bed operating characteristics, including the thermal efficiency, carbon capture efficiency, and sorbent half-life cannot be well understood. We focus on three primary parameters, solid-solid coefficient of restitution, solid-wall coefficient of restitution, and turbulence model, and consider how their influences vary at different bed solid fractions. This is accomplished via sensitivity analysis and the Bayesian Spline Smoothing (BSS) Analysis of Variance (ANOVA) framework. Results indicate that uncertainties approach 20% at high gas fractions, with the turbulence model accounting for 80% of this variation and the solid-solid coefficient of restitution accounting for the additional 20%.

abstract: The growing use of synthetic population, which is a disaggregate representation of the population of an area similar to the real population currently or in the future, has motivated the analysis of its sensitivity in the population generation procedure. New methods in PopGen have enhanced the generation of synthetic populations whereby both household-level and person-level characteristics of interest can be matched in a computationally efficient manner. In the process of set up, population synthesis procedures need sample records for households and persons to match the marginal totals with a specific set of control variables for both the household and person levels, or only the household level, for a specific geographic resolution. In this study, an approach has been taken to analyze the sensitivity by changing and varying this number of controls, with and without taking person controls. The implementation of alternative constraints has been applied on a sample of three hundred block groups in Maricopa County, Arizona. The two datasets that have been used in this study are Census 2000 and a combination of Census 2000 and ACS 2005-2009 dataset. The variation in results for two different rounding methods: arithmetic and bucket rounding have been examined. Finally, the combined sample prepared from the available Census 2000 and ACS 2005-2009 dataset was used to investigate how the results differ when flexibility for drawing households is greater. Study shows that fewer constraints both in household and person levels match the aggregate total population more accurately but could not match distributions of individual attributes. A greater number of attributes both in household and person levels need to be controlled. Where number of controls is higher, using bucket rounding improves the accuracy of the results in both aggregate and disaggregates level. Using combined sample gives the software more flexibility as well as a rich seed matrix to draw households which generates more accurate synthetic population. Therefore, combined sample is another potential option to improve the accuracy in matching both aggregate and disaggregate level household and person distributions. / Dissertation/Thesis / M.S. Civil and Environmental Engineering 2012

Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2018-06-26T20:13:42Z No. of bitstreams: 1 JUNIA DE LIMA NASCIMENTO – DISSERTAÇÃO (PPGH) 2017.pdf: 839040 bytes, checksum: e5b9014ed8e49c3e1f2ce355e1169965 (MD5) / Made available in DSpace on 2018-06-26T20:13:42Z (GMT). No. of bitstreams: 1 JUNIA DE LIMA NASCIMENTO – DISSERTAÇÃO (PPGH) 2017.pdf: 839040 bytes, checksum: e5b9014ed8e49c3e1f2ce355e1169965 (MD5) Previous issue date: 2017-06-27 / Capes / O presente trabalho dissertativo reflete sobre a maneira como os portadores da doença dos “Lábios Azuis” lidam com a mesma a partir do diagnóstico, na convivência diária até as limitações que se apresentam com a patologia. Para tanto, analiso o corpus documental constituído de inúmeras imagens, cujo suporte de escrita é o ciberespaço, como também entrevistas , para assim, chegar aos objetivos do projeto dissertativo. Para que esse trabalho se tornasse possível, lancei mão do conceito de experiência de Jorge Larossa que é primordial para dar um norte à pesquisa em voga, porque é a experiência discursiva dos enfermos que fornecem matéria prima para esta pesquisa. Em relação à análise do corpo enfermo, no contexto dos hospitais, utilizei Michel Foucault que nos traz a compreensão do nascimento da clínica, a disciplina médica sobre o corpo e o discurso médico para compreensão da enfermidade. O enlace da pesquisa é feita com uma escrita cheia de sensibilidade e histórias de vida que narram a convivência com essa patologia. / The present dissertation reflects on the way in which the patients of the "Blue Lips" disease deal with the same one from the diagnosis, in the daily coexistence until the limitations that present with the pathology. To do so, I analyze the documentary corpus consisting of numerous images, whose writing support is cyberspace, as well as interviews that have been transcribed by me, in order to reach the objectives of the dissertation project. In order for this work to become possible, I took advantage of Jorge Larossa concept of experience , which is paramount in giving a vogue to the research in vogue, because it is the discursive experience of the patients who provide the raw material for this research. Regarding the analysis of the diseased body, in the context of the hospitals, I used Michel Foucault that brings us the understanding of the birth of the clinic, the medical discipline on the body and the medical discourse to understand the illness. The link of the research is made with a writing full of sensitivity and life stories that narrate the coexistence with this pathology.

Cardiovascular disease (CVD) and type two diabetes mellitus (T2D) are among the leading causes of death worldwide. Insulin resistance (IR) and hyperglycaemia are risk factors for CVD and T2D and are known to be prevalent in youth. Physical activity (PA) is known to improve IR and glucose tolerance in youth, but current levels of PA are low meaning alternative PA recommendations are needed. The purpose of this thesis is to investigate the effect of low volume high-intensity interval exercise (HIIE) on insulin and glucose health outcomes in male children and adolescents. Additionally, the thesis will explore the potential for HIIE to improve glycaemic control in paediatric patients with type one diabetes mellitus (T1D). Chapter 4 examines the relationship between estimates of insulin sensitivity (IS) based on oral glucose tolerance test (OGTT) and fasted assessment methods, in addition to the day-to-day reliability of these measures in children and adolescents. Results from this chapter advocated the Cederholm index to measure IS in this sample due to the low day to day reliability (coefficient of variation (%CV) of 6.4%). Chapter 5 demonstrates comparable results, reporting moderate improvements to IS and glucose tolerance measured via an OGTT 10 minutes after a single bout of HIIE and work-matched moderate-intensity exercise (MIE) in adolescent boys (13-15 y old). The findings from Chapter 5 are extended in Chapter 6, where changes to OGTT derived IS and glucose tolerance were measured up to 24 h post exercise and fasting measures of IS up to 48 h after exercise. Improvements to IS and glucose tolerance after the OGTT persisted for up to 24 h after HIIE and MIE, but no changes to fasting outcomes were observed over the 48 h period. In contrast to Chapter 5, Chapter 7 reports that a single bout of HIIE but not work-matched MIE resulted in only a small improvement in IS in 8-10 year old boys. Chapter 8 assesses the efficacy of 6 sessions of HIIE performed over 2 weeks to alter fasting and postprandial (mixed-meal tolerance test) insulin and glucose outcomes in adolescent boys. In contrast to acute exercise (Chapters 5 and 6), HIIE training over 2 weeks did not improve insulin and glucose outcomes in this population. Finally, Chapter 9 presents a case study on three adolescents with T1D to examine the effect of acute HIIE and MIE on glycaemic control. This study indicates that both MIE and HIIE have the potential to improve short-term (24 h) glycaemic control within this clinical population. Taken collectively, the studies from this thesis demonstrate that HIIE offers an effectual and feasible alternative to MIE to improve insulin and glucose health outcomes in healthy children and adolescents, and short-term glycaemic control in adolescents with T1D.

There is no single test clinically available that is independently diagnostic for multiple sclerosis (MS). Currently MS is diagnosed using a combination of clinical evaluation and investigations including magnetic resonance imaging (MRI), interpreted in accordance with diagnostic criteria, to demonstrate the requisite dissemination of lesions in (anatomical) space and time. Lesions comprising inflammatory demyelination in the central nervous system are a core pathological feature of MS. Ultra-high field (e.g. 7 Tesla or 7T) T2*-weighted MRI can demonstrate in vivo a central vein in most of these lesions. This is a histopathologically specific feature which could be exploited to improve diagnostic workup in cases of suspected inflammatory demyelination. Central nervous system white matter not involved in demyelinating lesions is nevertheless affected in MS. The mechanisms inflicting injury to this normal appearing white matter (NAWM) and how they relate to focal lesions are unclear. Damage to NAWM seems important, because it correlates well with disability. Any association between cortical lesions, focal white matter lesions (WML) and diffuse damage to NAWM is difficult to investigate in vivo in MS, principally because MRI is relatively insensitive to cortical lesions. Investigation of such associations may also be confounded by the presence of small focal lesions within the “NAWM” that may remain undetected when using conventional MRI to define NAWM. Advantages inherent to ultra-high field MRI might help mitigate both of these problems.

[pt] Este trabalho apresenta uma metodologia para priorização de obras de Subtransmissão. Explorando-se as características radiais destes sistemas, utilizou-se a análise de Sensibilidade como ferramenta principal para se obter um índice que caracterizasse a Prioridade das Obras. / [en] This work presents a methodology for Priority Evaluation of Projects in Subtransmission System. The network particular characteristics were useful in using the Sensitivity Analysis applied as the principal tool in order to obrain an index to characterize Priority of the Project.