VictorJuiz/thesis huggingface dataset:
Multiwavelength studies of dust associated with galactic HII regions

The first part of this thesis describes the construction of a high resolution (~1') atlas of mid-infrared emission along part of the Galactic plane using Infrared Astronomical Satellite (IRAS) data processed using the HIRES algorithm. This emission generally arises from the smallest dust components in the interstellar medium (ISM) and is bright near HII regions due to the enhanced radiation field. The atlas (MIGA: Mid-Infrared Galaxy Atlas) has been combined with radio and far-infrared data as part of the Canadian Galactic Plane Survey. The remainder of the thesis presents the results of multiwavelength studies using MIGA. An accurate study of dust associated with HII regions requires a careful study of all of the components of an HII region and the surrounding ISM. A comparative study of the mid-infrared and radio continuum morphology of HII regions is presented. Understanding of this morphology is critical for the calculation of infrared fluxes and for the accurate association of infrared emission with a given HII region. Infrared ratio maps are a useful tool to study the properties of interstellar dust, but the construction of these maps is a non-trivial task with HIRES data. A new technique to construct these maps has been developed and is evaluated. For many HII regions of small angular extent the only available measurements are the global infrared luminosity and radio flux. An investigation was made of how much information about the structure of the HII region can be obtained from an analysis of these quantities. Accurate knowledge of the stellar content of an HII region is vital for the quantitative study of dust around HII regions. A new O-star spectral classification line ratio for heavily reddened OB stars has been developed. The HII region KR 140 is the subject of a multiwavelength study. KR 140 appears to be a region of spontaneous massive star formation. Submillimetre observations reveal complementary information about the dust, molecular cores, and possible protostars. Finally, infrared colour variations within molecular material surrounding the W5 HII region are investigated and ideas for further projects are presented.
Hermeneutics of written texts, religious discourse in Mexican literature

The aspiration of this thesis is towards a lucid understanding of the relationship between religious discourse and action in contemporary México. This question is approached through the study of the contemporary Mexican novel. However, in order to confront the arguments of art for art's sake, or of literature as a celebration of the enclosed world of language, it was necessary to integrate a theoretical discussion of the relationship between the written text and the world of action along with the exploration of the above-mentioned theme. The central problematic of the thesis was thus undertaken in two directions: (I) through an examination of the act of inscribing the world of action as written text, and (II) through analysis of the related issue of the referentiality of the written text to the world of action. The thesis is organized consistent with Ricoeur's conceptualization of the interpretation of texts as a three-fold mimesis; or, in Valdés' terms, with the three areas of engagement of the literary critic. Valdés' four stages of operation of literary criticism are integrated with these three areas, for these stages clearly serve to actualize Ricoeur's philosophical hermeneutics. This present work is thus divided into three major sections through which four sub-sections are interwoven. The first major section, "Prefiguration", provides the prefigurative basis for the work, briefly reviewing the philosophical tradition on which this thesis develops its innovations. These innovations are suggested with respect to the importance of ostensive references in inscribing the world of action, along with discussion pertinent to religious discourse and action as expressed in a selection of contemporary Mexican novels. The second major section, "Configuration", examines the act of inscribing the world of action. In this section, the phenomenon under study is religious discourse in the world of action of contemporary México. The third major section, "Refiguration", explores the manner in which the text, once written, refers to a world of action. In this section the phenomenon under study is no longer the world of action itself, but rather the written document. The work is concluded with a short section entitled "Return to the prefigurative". This section serves to provide a review and summary of the main arguments of the thesis. It also reflects the circular movement of open hermeneutic commentary, for such reflections are both grounded in tradition and return to it, enhancing the prefigurative matrix and offering possibilities for further innovation. (Abstract shortened by UMI.)
Hormone replacement therapy and the risk of breast cancer in postmenopausal women

The association between the use of hormone replacement therapy (HRT) and postmenopausal breast cancer was examined in the Ontario component of the Enhanced Cancer Surveillance (ECS) Project. Cases comprised 404 postmenopausal women ages 35-74 with incident, pathology confirmed breast cancer. They were compared to 403 postmenopausal controls, frequency matched to the cases on age strata. Information on risk factors was obtained through self-administered questionnaires. Women who used HRT for a duration of ten of more years (long-term users), within the past 5 years, were at an increased risk of breast cancer, relative to non-users (OR = 2.00, 95% CI = 1.13-3.53). The odds ratio for long-term users of progesterone in combination with estrogen was non-significantly higher (OR = 4.03, 95% CI = 1.11-14.64) than that for long-term users of estrogen alone (OR = 1.76, 95% CI = 0.94-3.30). Odds ratios were not significantly modified by family history, age group, smoking status, body mass index, alcohol consumption, type of menopause or ovarian status
Structures for Kalman-based detection over Rayleigh fading channels

Channel estimation is an essential part of many adaptive detection techniques proposed for data transmission over fading channels. For the frequency selective Rayleigh fading channel an autoregressive representation is proposed based on the fading model parameters. The parameters of this representation are determined based on the fading channel characteristics, making it possible to employ the Kalman filter as the best estimator for the channel impulse response. For IS-136 formatted data transmission, the Kalman filter is employed with the Viterbi algorithm in a Per-Survivor Processing (PSP) fashion and the overall bit error rate performance is shown to be superior to that of detection techniques using the RLS and LMS estimators. To allow more than one channel estimation per symbol interval, Per-Branch Processing (PBP) method is introduced as a general case of PSP. The Kalman filter can lead to significant improvement in the receiver bit error rate performance. However, a Kalman filter is a complex algorithm and is sensitive to roundoff errors. Different implementation methods are considered for measurement update and time update equations of the Kalman filter. The unit-Lower-triangular-Diagonal Correction (LDC) algorithm is used for the time update equations, and systolic array structures are proposed for its implementation. For the overall implementation of joint data and channel estimation, parallel structures are proposed to perform both the Viterbi algorithm and channel estimation. A new approach is proposed for the implementation of the Kalman filter based on differential channel states. This leads to a robust differential Kalman filtering algorithm that can be simplified further to ease the implementation without any major loss in performance.
Development and application of a diagnostic system for plasma spraying

An optical diagnostic system was built to measure the in-flight parameters of thermal spray particles. A ratio pyrometer was built to measure mean particle temperatures to within 100 K. Particle velocities and acceleration were recorded using a particle-tracking velocimetry system consisting of three pulsed lasers; a filtered, intensified CCD camera; and an image analysis macro in the software package OPTIMAS. Flow visualization of the emerging plasma jet was accomplished using smoke pellets for seeding and a laser sheet for illumination. The system was used to evaluate the performance of a new curvilinear gas shroud attachment and compare it with a commercially available conical attachment. The curvilinear attachment was found to increase particle temperatures by 300 K, leading to more complete particle melting. These favourable particle conditions resulted in higher quality coatings, displaying higher adhesion strength, lower porosity, and a more uniform microstructure than those applied with the conical nozzle. A new design for shrouding gas injection through a circular slot was tested and found to offer better protection to the particles in flight. The system was also used to measure impact conditions of nickel particles sprayed onto a preheated substrate. Individual nickel splats were examined under an electron microscope. A substrate transition temperature was found above which particle splashing ceases and splats become circular disks. Substrate preheating could potentially be applied in industry, as coating properties are highly dependent on interactions between splats. Measured particle impact conditions were also used to validate a numerical model of droplet spreading and solidification.
Tracing women's perceptions of their experiences in an early intervention centre program

The primary goal of this qualitative case study was to explore six women's perceptions of their experiences in an early intervention centre-based program. The program served families from psychopathological populations. Maternal deprivation, problematic mother/father-child relationships, marital stress, addictions, abuse, and poverty were evidenced to some degree or another in these families and in their nuclear families. The bulk of the work was dedicated to providing narratives of these women's lives and their experiences in the program. Within the context of their past and present experiences, each was able to extrapolate and individualize certain aspects of the program to meet their individual needs. The women attending the Family Enrichment Program were interviewed three times during the 1995–1996 school year October, February, and May. The sessions were tape-recorded and carried out on site and/or in either their homes or an alternate place. Ages for the women ranged from 19 to 31; educational levels from Grade 8 to college; marital status included common law, separated, and married; and they had from 1 to 3 children (under 5) per family. Through the perceptions of these women, two salient features were noted: the environment into which they came, and the caregiver's responsiveness to them and to their children. Being in a nurturing and secure environment in which caregivers exuded confidence, encouragement and acceptance of the participants' potential as women, daughters, partners and parents, appear to be among the factors that these women perceived as being important. The genuine concern, care and love expressed by the staff and volunteers broke down the women's resistance, reservations and mistrust. By being affirmed and recognized in their own right, these women gained more self-confidence, self-awareness and feelings of self-advocacy. The large number of volunteers assisting in child-care enabled participants to leave their children, secure in the belief that the youngsters would be well cared for. Moreover the one-on-one ratio of volunteer to child enabled their children to gain an independence from their parents to socialize, explore and venture into many unknown areas denied them in their own environments.
Toward the asymmetric synthesis of the AB-ring system of phorbol

A second-generation asymmetric synthesis of the AB-ring system of phorbol was investigated. This study has alleviated the problems associated with the first generation racemic synthesis of the AB-ring system. The key step in the approach is an intramolecular anionic cyclization reaction, which effectively forms the trans-5,7-fused AB-ring. Chiral auxiliaries and the asymmetric aldol reaction were utilized to furnish the appropriate stereochemistry. The formation of the [3.2.1] oxabicycle 63 was achieved using the Rh-catalyzed [4+3] cycloaddition reaction, which imparts high diastereoselectivity. A selective zinc reduction was performed to give 64 with the hydroxyl and methyl groups restored in a 'syn' orientation to each other. Cleavage of the chiral auxiliaries proved troublesome, however, under the Krapcho conditions, selective removal of R-pantolactone was achieved. Further manipulations involving protections, reductions and cleavage reactions were investigated. The precursors en route to the AB-ring have been made and the conditions have been optimized.
Maintenance performance management in capital intensive organizations

Given the significance of maintenance in today's operating environment, excellence in maintenance performance becomes a strategic issue of capital intensive organizations. Managing for excellence needs effective measurement of performance. Whilst organizational performance measurement in general has been discussed extensively in the literature, few of these discussions focus specifically on the maintenance function. The overall objective of this research project is to study the role measurement can play in managing maintenance performance. In the initial phase of the inquiry, eight maintenance organizations in Hong Kong and Canada were visited and interviews were conducted during these visits. Findings from such field work indicate that maintenance organizations seldom measure their performance using a balanced set of indicators, or regard performance measurement as a strategic management tool. An approach that involves the use of strategy driven balanced scorecards, has been proposed to enhance effectiveness of maintenance performance management. Given its novelty, the proposed approach had to be put into practice to validate its efficacy. Two maintenance organizations were involved as collaborating parties in an action research to study the application of balanced scorecards as the tool for managing maintenance performance. Observations from the action research indicate that the initial balanced scorecards developed by maintenance organizations are typically machine-centric, rich in outcome measures but poor in performance drivers, with weak linkage between scorecard measures and the espoused strategy of the maintenance organization. The tools for the design and deployment of the maintenance scorecards, and those for the presentation and analysis of scorecard results were identified and field tested. Conditions conducive to successful applications of balanced scorecards in maintenance organizations are found to include: existence of a participative and social process, widespread understanding of the balanced scorecard concept, the maintenance strategy is widely communicated, the momentum of change is sustained, and the support infrastructure is in tune with the espoused strategy. Two propositions are derived from the results of the action research viz: Proposition 1--' Maintenance performance management is emphasized in organizations where maintenance is regarded as an investment, an integral part of asset management, and where managers have a holistic but not machine-centric mind-set'. Proposition 2--' Managers with a good understanding of the balanced scorecard concept will be able to use the balanced scorecard to inform people of the key result areas and show them how exemplary maintenance performance in these areas can be achieved'. The five-step framework proposed in this study provides the road-map for applying balanced scorecards in managing maintenance performance. The design of the maintenance system that will fit in the specific operating environment can be guided by the soci-technical system-based framework suggested in this thesis.
RHAMM, CD44 expression and erk activation are linked in malignant human breast cancer cells and are associated with cell motility

We assessed CD44, RHAMM, erk, and ras expression in human breast cancer cell lines that vary as xenografts in nude mice. Compared to MCF-7 cells, MDA-MEB-231 cells expressed higher levels of CD44, RHAMM, erk, and ras, showed higher levels of cell surface RHAMM, and displayed greater motility that was reduced by anti-RHAMM or anti-CD44 antibodies, or by a MEK inhibitor. These inhibitors also reduced the motility of mutant active ras-transfected MCF-10A cells which, relative to wild-type ras or empty vector transfected cells, were more motile and had increased RHAMM, CD44 and activated erk expression. MDA-MB-231 cells and mutant ras-transfected MCF-10A cells demonstrated nuclear co-localization of RHAMM and erk, whereas RHAMM and CD44 co-localized to perinuclear regions or to cell processes. Co-immunoprecipitation of RHAMM with both CD44 and erk was also observed. These results suggest that RHAMM and CD44 may coordinate signaling through the ras-MAP kinase pathway to control cell motility.
The effect of reference environments on the accuracy of the results of an exergy analysis of an aerospace engine

An exergy analysis is applied to a turbojet engine for a range of altitudes from 0 to 15,000 m (~50.000 ft) and for a 3,500 km flight to examine the effects of using different reference-environment models. The results of tins analysis using a variable reference environment (equal to the operating environment at all times) are compared to the results obtained using two constant reference environments (0 and 15,000 m). The rational efficiency of a turbojet was observed to decrease with increasing altitude, due mainly to an increase in exhaust exergy emissions. The accuracy of exergy results was found to be dependent on the choice of reference environment, where the use of a constant reference environment can lead to errors as large as 52%. For most atmospheric applications, the use of a variable reference environment does not add great complexity to the exergy analysis while yielding the most accurate results.
Performance of latency constrained turbo-like codes over correlated fading channels

The problem of interleaving transmitted symbols over fading channels is investigated. Clarke's model is used to simulate a correlated flat fading channel. The performance of block interleaved convolutional codes is studied in terms of bit and word interleavers and their equivalent super channels. It is shown that a bit interleaved channel can be represented in terms of a super channel of equivalent Doppler spread. Performance of various interleaved convolutional codes is compared to those of non-interleaved turbo-like codes in a correlated fading environment. Simulation results indicate that under stringent delay constraints such as voice communications, interleaved convolutional codes outperform turbo-like codes. However at more relaxed delay constraints of a few thousand bits, non-interleaved turbo-like codes are capable of outperforming convolutional codes.
Biochemical analysis of activating mutations of the kit receptor tyrosine kinase

The recent identification a number of activating Kit mutants in human cancers has increased the need and the importance of understanding the oncogenic properties and biochemical mechanisms of the oncogenically mutated Kit receptors. In this thesis, I provide biological evidence that expression of either Kit$\rm\sp{KDY}$ or Kit$\rm\sp{G559}$ in IC2 cells leads to the degradation of the protein tyrosine phosphastase, Shp-1 and the relocalization of many signalling proteins downstream of the Kit receptor to the cytoskeletal fraction of the cell. One of the aberrantly localized proteins is the adaptor protein Shc, which is involved in activation of the Map kinase pathway and is a potential substrate of Shp-1. In addition, I also provide biochemical evidence which suggests that tyrosine phosphorylation may be required for the relocalization of Shc to this insoluble fraction of the cell. I further demonstrate through immunofluoresence staining that Shc is co-localized with the Kit receptor to a "cap" like area of the cell membrane after Steel factor stimulation and that the majority of Shc and Kit are localized to this area in IC2/KDY and IC2/G559 cells. This data suggests that the relocalization of Shc and other proteins downstream of the Kit receptor may be involved in the transformation of IC2 cells expressing KDY and G559. Furthermore, these results help further elucidate the molecular mechanisms underlying the malignant transformation by both KDY and G559 and further demonstrate the importance of Shp-1 as an important attenuator of the Kit signalling pathway.
Polyelectrolyte induced domains in cationic lipid bilayer membranes, a deuterium nuclear magnetic resonance perspective

The effect of membrane surface charge was studied via deuterium ( 2H) and phosphorus (31P) nuclear magnetic resonance (NMR), by the addition of amphiphilic cationic charge into a neutral phospholipid membrane and then subsequent neutralization of this charge through the addition of anionic polyelectrolyte. The effect of added charge was monitored by the use of a specifically deuterated phosphatidylcholine molecule which produces a predictable change in the 2H NMR quadrupolar splitting ([Delta][nu] Q) in response to changes in membrane surface charge. Addition of amphiphile cationic charge produced a decrease (increase) in the quadrupolar splitting for the a Ã (ß) deuterons. The subsequent addition of anionic polyelectrolytes onto these cationic surfaces induced the appearance of a dual component spectrum consisting of two quadrupole splittings indicative of two different charge environments. While one charge population is enriched in cationic charge the other is depleted, Therefore, the addition of polyelectrolyte induces the existence of long lived lateral inhomogeneities or domains at the cationically charged membrane surface. The degree of separation and the composition of the domains was quantified through spectral simulations. The data show that domain formation and composition depended greatly on the identity and size of polyelectrolyte, the initial cationic surface charge, in addition to the ionic strength of the solution. The effect of anionic polyelectrolytes was also studied via 2H NMR of methyl-deuterated cationic amphiphiles. Although this data produced no evidence of domain formation, information was obtained which supported the results gained from deuterolabeled phosphatidylcholine. The results also indicated that the polyelectrolyte orders the headgroup of cationic amphiphiles and that salt addition reduces this electrostatic interaction. Finally, the behaviour of two nucleotides as well as the macroscopic architecture of these mixed membrane systems was followed via 31P NMR. These results show that polyelectrolytes bound to these cationic surfaces become immobilized. The data also indicate that the lipids retain a bilayer arrangement, under most conditions. However, various non-bilayer phases were produced when phosphatidylcholine was replaced with phosphatidylethanolamine, in the absence and presence of polyelectrolyte. Non-bilayer phases could also be produced in the presence of double chained cationic lipids but not single chained cationic amphiphiles.