Thesis (Ph. D.)--Chemical Engineering, Georgia Institute of Technology, 2009. / Committee Co-Chair: Eckert, Charles; Committee Co-Chair: Liotta, Charles; Committee Member: Bommarius, Andreas; Committee Member: Fernández, Facundo; Committee Member: Lu, Hang. Part of the SMARTech Electronic Thesis and Dissertation Collection.

This thesis describes two main sections of work, an examination of a commercial product, Intrasite Gel, and the development of an algorithm for variable selection using projected latent structures.Following on from the successful development of a variable selection procedure for multivariate linear regression this work looks at transferring this idea for use with projected latent structures. The first part of this thesis will show how the variable selection algorithm was developed and used with three different data sets. The algorithm will be shown to be superior to standard projected latent structures, for linear multi-component data. Although the final algorithm developed requires considerable computing resources to carry out this is compensated for by significantly improved model predictions and robustness. The final algorithm developed is written to run using MATLAB on any computer platform that supports this application, though the principles of operation could be transferred to another method of execution, for example custom code written in C or Pascal. The approach used in the development of this method is that the ability of the model to predict unknownsamples is of far greater importance than the internal performance of the model. All the assessments of the procedures developed are based on the ability of the model to predict accurately and precisely samples that were not presented to the model during the training stage.The second section of this thesis is concerned with the study of Intrasite Gel, produced by Smith & Nephew Ltd. Hull. The material in question is a medical device intended to assist in the treatment and healing of wounds that are necrotic, sloughy or granulating. The product is characterised by its ability to maintain moisture equilibrium in a wound environment and to provide a suitable medium to encourage the growth of new cell tissue. Medical devices require registration, and as part of that registration a number of tests are made on samples to ensure that the material meets the required specifications. There was some concern at Smith & Nephew that the tests they were required to carry out as part of the device registration were not providing appropriate information about the product. Of particular interest was the fluid absorption property as it was suspected that the test has a large amount of random error associated with it and an investigation was required to examine this test and to provide an alternative procedure should the fluid absorption test prove inadequate. Also of interest to Smith & Nephew was the issue of sampling frequency, as it was felt that this should also be examined to determine whether the correct rate of sampling to ensure product quality was being carried out. The work reported here shows that the fluid absorption test as it stands is insufficient to the task of monitoring this property of Intrasite gel and that an alternative test should be considered. This work also showed that current sampling rate was too high and that the high sampling rate may in fact cause misleading assumptions as to the stability and quality of the product.

Thesis (M.S.)--Drexel University, 2005. / Includes abstract. Includes bibliographical references (leaves 46-49).

No description available.

The purpose of this study was to develop an incremental field exercise test of disability to use in the assessment of functional capacity in patients with chronic airways limitation (CAL). The test was modified from the 20m shuttle running test, employed to predict the maximal oxygen uptake of sporting individuals. The protocol devised for the patients was adapted from the running speeds proposed by Leger and Lambert (1982). The shuttle walking test requires patients to walk up and down a 10m course at speeds dictated by a series of audio signals played from a tape cassette, increasing each minute to a symptom limited maximum performance. Examination of the reproducibility of the test revealed strong test/retest reliability, after just one practice walk. The mean between trial difference (test 2 vs test 3) was -2m,(n=10), (95% CI -21.9 to 17.9m). The shuttle walking test was validated against the traditional measurement of peak oxygen uptake (Vo2pmk) measured conventionally during an incremental maximal treadmill test with Douglas bags (n=19). The results from this exercise test were compared against the patients' performance (distance achieved) on the shuttle walking test (after one practice walk) and revealed a strong relationship between the two variables (r=0.88). The validity and the resistance to breathing, of a portable oxygen consumption meter was examined. Validation, again in comparison to Douglas bag measurements, involved four cohorts (two healthy and two patient groups). After some modifications to the equipment, measurements of lib2 by the two different methods were not significantly different. The patients' response to the shuttle walking test was examined (n=10). The heart rate, ventilation and 7Orck2 increased gradually in response to the increasing intensity of the shuttle walking test. Again Vo 2wa measurements related strongly to the patients performance (r=0.81). A further study employing a treadmill test and shuttle walking test confirmed that the latter provided a comparable metabolic and physiological challenge to the patients as the conventional treadmill test. Comparison with the 6 minute walking test (6MWT), one of the most commonly employed field exercise tests in this patient population) revealed that the heart rate response was significantly higher in the shuttle walking test than the 6 MWT and graded, a response not observed in the 6MWT. The shuttle test reflected the true extent of the patients disability more accurately than the 6MWT. The shuttle walking test provides a simple, reproducible exercise test of disability in patients with CAL that relates well to Vb2puk . The external pacing of the test allows more valid intra- and inter- subject comparison than has previously been possible with field tests alone.

Dyestuffs are widely used industrial chemicals, yet surprisingly little is known about their fate in the environment. The potential modes of transformation and removal of reactive dyes in treatment and in the environment are principally through anaerobic and aerobic biodegradation and photodegradation. The research herein describes the use of LC-MS analysis with laboratory simulations to develop a better understanding of the occurrence and fate of reactive dyes and their degradation products in the aquatic environment. One reason for the lack of information on the environmental fate of reactive dyes has been the paucity of robust analytical methods suitable for the determination of dyes in aqueous samples. Robust analytical methods were optimised to provide LC-MS and MSMS identification of degradation products. Additionally, interpretation of the MSMS spectra of known reactive dyes provided novel characteristic fragment ions indicative of the triazine reactive group of reactive dyes . Fibre reactive dyes are designed to have a degree of photostability and therefore their photodegradation behaviour has not been widely investigated. Little is known of their stability to daylight over prolonged periods of irradiation in dilute aqueous solutions and in the presence of humic substances. The kinetics of photodegradation of an anthraquinone dye (Reactive Blue H4R) and azo dye (Reactive Yellow P5G) were evaluated. The former underwent rapid and extensive degradation 01/2 1.5 h). The major products formed were identified using LC-MSMS and a photodegradation pathway proposed. By comparison, the photodegradation of the azo dye was significantly slower, 01/2 30 h). The addition of humic substancesa ppearedt o have little effect on the rate of photodegradationu nder the conditions used. The reduction of azo dyes under anaerobic treatment has been extensively studied, but the subsequent fate of the initial reduction products when exposed to air are not understood. Three relatively simple azo dyes, Amaranth, Sunset Yellow and Naphthol Blue-Black, were reduced and their autoxidation products identified by LC-MS. These were subsequently used to predict the autoxidation products of a more complex azo reactive dye: Reactive Red 3.1. Additionally, a persistent degradation product from the anaerobicaerobic treatment of Reactive Red 3.1 was identified from LC-MS data. Azo reactive dyes are generally regarded as being resistant to aerobic degradation and there are few published data regarding degradation pathways for reactive anthraquinone dyes. Pure cultures of Pseudomonas docunhae, A 9046 and A texaco and mixed bacterial consortia (semi-continuous activated sludge, SCAS) aerobic degradation of azo and anthraquinone reactive dyes was studied. Two azo dyes were degraded by pure cultures of A docunhae and A 9046, suggesting that azo dyes can be aerobically degraded given favourable conditions. The antraquinone dye was extensively degraded by SCAS and pure culture biodegradation. Metabolites were identified by LC-MS and a degradation pathway proposed.

Thesis (Ph. D.)--Rutgers University, 2010. / "Graduate Program in Chemical and Biochemical Engineering." Includes bibliographical references (p. 209-237).