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Korovkin approximation in function spaces /Yeung, Man-chung. January 1900 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1990.
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Pointwise Korovkin approximation in function spaces /Ng, Cheuk-yan. January 1993 (has links)
Thesis (Ph. D.)--University of Hong Kong, 1993.
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Mass transfer studies of pulmonary functionHobbs, Simon H. January 1979 (has links)
Thesis--University of Wisconsin--Madison. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 255-265).
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Luminosity functions for old stellar systemsBergbusch, Peter Anthony 03 July 2018 (has links)
The potential for luminosity functions (LFs) of post-turnoff stars to constrain basic cluster parameters such as age, metallicity, and helium abundance is examined in this dissertation. A review of the published LFs for the globular cluster (GC) M92 suggests that the morphology of the transition from the main sequence to the red giant branch (RGB) is sensitive to these parameters. In particular, a small bump in this region may provide an important age discriminant for GCs. A significant deficiency in the number of stars over a 2 mag interval, just below the turnoff, remains unexplained.
A method of interpolating isochrones and LFs accurately from evolutionary sequences, from the lower main sequence to the RGB tip, is discussed. The interpolation scheme is based on primary interpolation points which are identified by the behaviour of the derivative [special characters omitted] along an evolutionary sequence.
New BV CCD observations, calibrated with Landolt and Graham standard stars, for the old open cluster NGC 2243 and for the bright stars in the GCs NGC 288 and NGC 7099 are presented. The colour magnitude diagram (CMD) of NGC 2243 contains a strong binary star component. Comparisons with the fiducial sequences of the GC 47 Tuc (Hesser et al. 1987) indicate that the two clusters have similar abundances, while comparisons with the new oxygen-enhanced isochrones (Bergbusch & VandenBerg 1992) suggest that NGC 2243 has an age of 4-5 Gyr, and a metallicity [special characters omitted]. The morphology of both the CMD and the LF through the turnoff region cannot be attributed to the merging of the binary and single star sequences, but convective overshooting works in the correct sense to account for the differences between the isochrones and the CMD.
For NGC 288 and NGC 7099, excellent overall consistency among the Zero-Age Horizontal Branch, isochrone, and LF fits is obtained for cluster ages of 14-16 Gyr. The manifestation of the transition bump in NGC 288's LF provides a particularly strong constraint on the age, since this feature becomes more prominent as the metallicity increases. R-method helium abundance estimates give Y ≈ 0.23 for NGC 288 and Y ≈ 0.31 for NGC 7099. The 2nd parameter problem is discussed in light of these results. The RGB bump, present in canonical LFs, is only weakly identified in the cumulative LF (CLF) of NGC 288, and may not be present at all in NGC 7099's CLF. However, the brightest RGB stars in both clusters are found within ≈ 0.2 mag of the RGB tip predicted by the oxygen-enhanced models. / Graduate
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Iodine in the vegan dietLightowler, Helen January 1997 (has links)
Various potential nutrient deficiencies associated with the vegan diet have been thoroughly investigated, but limited research has been undertaken to assess the iodine intake of vegans. Moreover, such research may be considered unreliable. Therefore, the aims of the current work were to firstly ascertain the main sources of iodine in the vegan diet, both dietary and pharmacological, and their frequency of consumption. Secondly, it was intended, by way of a prospective cross-sectional study, to determine the iodine intake of vegans consuming their habitual diet, and their iodine status. The current sources of iodine in the vegan diet and the frequency of consumption were assessed in 378 replies to a questionnaire advertised in 'The Vegan' - the official magazine of the Vegan Society. The main sources of iodine were identified as seaweed and seaweed products, iodised salt and iodine supplements. Over 1 in 4 of the volunteers were not consuming any of these sources and 54% were consuming only one source. Conversely, 19% were consuming at least two of the three identified sources. The preliminary findings suggested that vegans may be at risk of both iodine deficiency and toxicity and that iodine consumption was largely dependent on the iodine content of the food, the portion size and the frequency of consumption. Thirty 'healthy' vegans were recruited to the prospective study. Duplicate portions and 24 hour urine specimens were collected concurrently over four consecutive days and the iodine intake and status determined by chemical analysis. Dietary intake was also recorded and iodine intakes were determined by Comp-Eat, a computerised nutritional analysis program, to assess the reliability of this dietary survey technique. The iodine intake of the majority of the subjects was below the RNI and even below the LRNI. Moreover, the iodine status of the majority of the group investigated was low. Conversely iodine intakes of those who consumed seaweed approached levels which may be considered toxic. These findings indicate that iodine intakes may be low, however it is uncertain as to whether or not the body is able to adapt to such intakes. Furthermore, the potential effect on thyroid function of possibly toxic, but infrequent, intakes of the trace element is unclear. Finally, the study exposed a need for the availability of reliable information on iodine for vegans.
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Microvascular function in patients undergoing chemotherapySutterfield, Shelbi Lorrae January 1900 (has links)
Master of Science / Department of Kinesiology / Carl Ade / Adjuvant systemic chemotherapy for the treatment of certain cancers, particularly breast and lymphoma, adversely impacts cardiovascular health. However, the extent to which it impairs endothelial function is not well understood. Therefore, the purpose of this study was to determine if microvascular and macrovascular endothelial-dependent vasoreactivity is attenuated in breast cancer and lymphoma patients currently being treated with chemotherapy compared to healthy counterparts. With laser Doppler imaging, cutaneous microvascular function was evaluated via changes in cutaneous vascular conductance (CVC) in response to iontophoresis of acetylcholine (ACh). Endothelium-dependent flow-mediated dilation (FMD) was evaluated in the brachial artery via ultrasonography. CVC responses to iontophoresis of ACh in the cutaneous microcirculation was significantly lower in cancer patients than in control subjects (cancer (n=7): 959.9 ± 187.3%; control (n=7): 1556.8 ± 222.2%; P = 0.03). Furthermore, FMD was significantly lower in cancer patients than in control subjects (cancer: 2.2 ± 0.6%; control: 6.6 ± 1.4%; P = 0.006). These data provide evidence of microvascular and macrovascular dysfunction in breast cancer and lymphoma patients currently undergoing adjuvant chemotherapy, which may contribute to the increased long-term risk of cardiovascular disease morbidity and mortality in those treated for cancer.
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Conceptions of Function Composition in College Precalculus StudentsJanuary 2014 (has links)
abstract: Past research has shown that students have difficulty developing a robust conception of function. However, little prior research has been performed dealing with student knowledge of function composition, a potentially powerful mathematical concept. This dissertation reports the results of an investigation into student understanding and use of function composition, set against the backdrop of a precalculus class that emphasized quantification and covariational reasoning. The data were collected using task-based, semi-structured clinical interviews with individual students outside the classroom. Findings from this study revealed that factors such as the student's quantitative reasoning, covariational reasoning, problem solving behaviors, and view of function influence how a student understands and uses function composition. The results of the study characterize some of the subtle ways in which these factors impact students' ability to understand and use function composition to solve problems. Findings also revealed that other factors such as a students' persistence, disposition towards "meaning making" for the purpose of conceptualizing quantitative relationships, familiarity with the context of a problem, procedural fluency, and student knowledge of rules of "order of operations" impact a students' progress in advancing her/his solution approach. / Dissertation/Thesis / Ph.D. Mathematics 2014
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Molecular analysis of actinidinPräkelt, Uta M. January 1987 (has links)
Actinidin, the 23.6 kDa cysteine proteinase of Chinese gooseberry (Actinidia chinensis), is present at high concentration in fruits. A fruit-specific cDNA library was established and screened by differential hybridisation and using a synthetic oligonucleotide. Two of ten actinidin clones identified were characterised by sequence analysis. The two very similar cDNAs code for proteins with approximately 90% sequence homology to the published amino acid sequence of actinidin, as well as an additional 25 amino acids following the mature carboxyl terminus. The larger clone in addition has coding potential for 57 residues of an amino-terminal extension with considerable homology to amino-terminal sequences of other cysteine proteinases. From size determinations of both mRNA (1.4 kb) and immunoprecipitated in vitro translation product (39 kDa) it was estimated that actinidin is synthesised as a precursor approximately 15 kDa larger than the mature protein. Features of the prosegment primary sequence are considered with regard to a possible mechanism of inactivation of the proteinase, by analogy with other proteolytic zymogens. The presence of three potential glycosylation sites, one within the carboxy-terminal and two in the amino-terminal extension are consistent with subcellular location of the enzyme within membrane-bound organelles. Results from a Southern blot show that actinidin is encoded by a multigene family of up to ten members. Actinidin gene expression, both at the level of mRNA and protein, is largely restricted to the fruit of A. chinensis, where the level of actinidin mRNA accumulates early during development.
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Toward a Theory of Formal Function in Stravinsky’s Neoclassical Keyboard WorksMueller, Peter M., Mueller, Peter M. January 2018 (has links)
Form in Stravinsky’s music continues to be a topic of great interest and varied approaches, including blocks, stratification, juxtaposition, and displacement. This document provides another approach based heavily on the models proposed by William E. Caplin in his Classical Form: A Theory of Formal Functions for the Instrumental Music of Haydn, Mozart and Beethoven. The study focuses on three piano works from Stravinsky’s early Neoclassical period. The document begins with a review of how other analysts have approached form in Stravinsky’s music, followed by on overview of how Caplin’s theory has been applied to works by other composers. Next, since Caplin relies heavily on cadential harmonic progressions of the common-practice period, I propose alternative parameters to define relative conclusions in music, such as motive, rhythm, and counterpoint. Armed with these new cadential constructs, called endings, I identify constituent Caplinian functions (presentations, antecedents, continuations, etc.) which can then be used to construct theme-types, which in turn function as constituent types for larger forms. I also categorize several loosening agents that Stravinsky uses to deviate from normal, balanced theme-types. The final chapter summarizes the research, applies the theory to other works by Stravinsky and other composers, and proposes topics for future analysis.
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Studies of plasma membrane function in human hypertensionRiozzi, A. January 1988 (has links)
Considerable evidence has emerged in recent years to suggest that the cell plasma membrane handles univalent and divalent cations abnormally in patients with untreated essential hypertension. Many of the phenomena originally discovered in patients with the established disease have now been found to occur in the genetically hypertension-prone offspring of hypertensive patients when their blood pressure is normal. The studies described in this thesis were designed to investigate the mechanisms which might explain these disturbances of membrane function. The first experiments were performed to investigate whether a circulating blood-borne factor might be present in excess in hypertensive patients and their relatives and by exposing cells from subjects with normal blood pressure and no family history to serum from patients and their offspring, the object was to try and reproduce the findings in hypertension. These studies were negative. Because of many reports of an overactive sympathetic nervous system in hypertension leucocytes were exposed to noradrenaline and this was found to influence sodium transport in cells from control subjects suggesting that at least some of the phenomena described in hypertension might be related to autonomic dysfunction. An alternative hypothesis to explain these abnormalities is that there is a genetically predetermined disturbance of the physicochemical structure of the plasma membrane which alters its function. The abnormality might well lie within the lipid fraction of the cell membrane. Attempts to alter this were undertaken using changes in dietary fat intake. These lowered blood pressure slightly and indeed altered sodium influx. The final series of experiments involved detailed examination of one fraction of plasma membrane phospholipids which is highly metabolically active, namely the phosphoinositides, and indeed using red cells it was possible to demonstrate that these lipids are overactive in the early stages of hypertension. These findings suggest that the plasma membrane is structurally abnormal in hypertension, the abnormality may reside in the phospho- inositide lipids and may possibly be susceptible to dietary manipulation.
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