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It remains unclear whether airway smooth muscle (ASM) mechanics is altered in asthma. While efforts have originally focussed on contractile force, some evidence points to an increased velocity of shortening. A greater rate of airway renarrowing after a deep inspiration has been reported in asthmatics compared to controls, which could result from a shortening velocity increase. In addition, we have recently shown in rats that increased shortening velocity correlates with increased muscle shortening, without increasing muscle force. Nonetheless, establishing whether or not asthmatic ASM shortens faster than that of normal subjects remains problematic. Endobronchial biopsies provide excellent tissue samples because the patients are well characterized, but the size of the samples allows only cell level experiments. Whole human lungs from transplant programs suffer primarily from poor patient characterization, leading to high variability. ASM from several animal models of asthma has shown increased shortening velocity, but it is unclear whether this is representative of human asthma. Several candidates have been suggested as responsible for increased shortening velocity in asthma, such as alterations in contractile protein expression or changes in the contractile apparatus structure. There is no doubt that more remains to be learned about the role of shortening velocity in asthma.

Scope and Content stated in the place of the abstract. The principal methods of calculating nuclear spin coupling constants by applying perturbation theory to molecular orbital wavefunctions for the electronic structure of molecules are discussed. A new method employing a self-consistent-field perturbation theory (SCFPT) is then presented and compared with the earlier methods. In self-consistent-field (SCF) methods, the interaction of an electron with other electrons in a molecule is accounted for by treating the other electrons as an average distribution of negative charge. However, this charge distribution cannot be calculated until the electron-electron interactions themselves are known. In the SCF method, an initial charge distribution is assumed and then modified in an iterative calculation until the desired degree of self-consistency is attained. In most previous perturbation methods, these electron interactions are not taken into account in a self consistent manner in calculating the perturbed wavefunction even when SCF wavefunctions are used to describe the unperturbed molecule. The main advantage of the new SCFPT approach is that it treats the interactions between electrons with the same degree of self-consistency in the perturbed wavefunction as in the unperturbed wavefunction. The SCFPT method offers additional advantages due to its computational efficiency and the direct manner in which it treats the perturbations. This permits the theory to be developed for the orbital and dipolar contributions to nuclear spin coupling as well as for the more commonly treated contact interaction. In this study, the SCFPT theory is used with the Intermediate Neglect of Differential Overlap (INDO) molecular orbital approximation to calculate a number of coupling constants involving 13c and 19F. The usually neglected orbital and dipolar terms are found to be very important in FF and CF coupling. They can play a decisive role in explaining the experimental trend of JCF among a series of compounds. The orbital interaction is found to play a significant role in certain CC couplings. Generally good agreement is obtained between theory and experiment except for JCF and JFF in oxalyl fluoride and the incorrect signs obtained for cis JFF in fluorinated ethylenes. The nature of the theory permits the latter discrepancy to be rationalized in terms of computational details. The value of JFF in difluoracetjc acid is predicted to be -235 Hz. The SCFPT method is used with a theory of dπ - pπ bonding to predict in agreement with experiment that JCH in acetylene will decrease when that molecule is bound in a transition metal complex. Thesis Doctor of Philosophy (PhD)

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Soil vapour extraction (SVE) is a widely accepted and cost-effective technique used to remediate unsaturated soils contaminated with volatile organic compounds (VOCs). In order to improve SVE design, it is necessary to develop a comprehensive mathematical model that incorporates multiphase flow and multicomponent transport with nonequilibrium mass transfer. The model must include key controlling parameters such as relative permeability, dispersion coefficients, phase densities and interphase mass transfer. Research has been completed on comprehensive three-dimensional SVE models entitled 3D-SVE-L/F. Use of these models allows quantitative evaluation of the SVE tailing effect, a current obstacle for SVE technology. The numerical solutions of the 3D-SVE-L/F models are obtained using FEMLAB, a commercial multi-physics modeling software developed by COMSOL Inc.; 3D-SVE-L/F have been calibrated against known data from lab-scale and field-scale SVE operations. The numerical simulation study indicates that 3D-SVE-L/F models can simulate SVE tailing effects. Accordingly, the pressure field and the distribution of the concentration of contaminant in the soil gas phase as well as the saturation reasonably are predicted. The completed multivariable sensitivity analysis of the calibrated 3D-SVE-L/F models under a 95% confidence interval manifests that empirical mass transfer parameters consisting of the NAPL to vapour mass transfer coefficient are the most sensitive, followed by air-phase permeability. Dispersivity is the least sensitive. Comparison of the mass transfer coefficients between lab and field has shown that the field conditions are more resistant to mass transfer, consistent with high water content, more complex soil properties, and site heterogeneity. A challenge facing SVE designs is estimating the length of SVE treatment time using a 3D-SVE model; a concept referring to a critical time index (CTI) was developed to predict the closure time for stopping an SVE operation. Applying CTI to an SVE operation may save operational time and cost. Additionally, the 3D model developed in this study can be used to assist in field-scale SVE design.

Competencies have been used for many years to align the values, behaviour, knowledge, and skills of individuals with the goals of the organizations in which they are employed. The organization in which I am employed in the role as a technical instructor, previously did not have a curriculum in place to support a competency-based model for the apprentices who are working in an aviation maintenance capacity. This action research paper outlines the redesigned curriculum, grafting reflective and social learning aspects; the result of is intended to affect positive change in the learning practices of both the individual and organization.

The jet energy scale (JES) and its systematic uncertainty are determined for jets measured with the ATLAS detector using proton-proton collision data with a centre-of-mass energy of √s=7 TeV corresponding to an integrated luminosity of 4.7 fb −1. Jets are reconstructed from energy deposits forming topological clusters of calorimeter cells using the anti-kt algorithm with distance parameters R=0.4 or R=0.6, and are calibrated using MC simulations. A residual JES correction is applied to account for differences between data and MC simulations. This correction and its systematic uncertainty are estimated using a combination of in situ techniques exploiting the transverse momentum balance between a jet and a reference object such as a photon or a Z boson, for 20≤pjetT1 TeV. The calibration of forward jets is derived from dijet pT balance measurements. The resulting uncertainty reaches its largest value of 6 % for low-pT jets at |η|=4.5. Additional JES uncertainties due to specific event topologies, such as close-by jets or selections of event samples with an enhanced content of jets originating from light quarks or gluons, are also discussed. The magnitude of these uncertainties depends on the event sample used in a given physics analysis, but typically amounts to 0.5-3 %.

Improving the understanding of the way neurons interact at the whole-brain level is of great interest to neuroscientists. These “circuit diagrams” of the human brain could revolutionize the way neurological diseases are treated, but before this level of study can be conducted, neuroimaging technology must be improved. Using the model organism Drosophila melanogaster, improvements in spatiotemporal resolution of microscopy techniques are being made. Microfluidic devices have been created to improve the spatial resolution of live neuroimaging in Drosophila 3rd instar larva using confocal microscopy, but the desired high temporal resolution has not yet been demonstrated in a live organism. In this research, the high spatial resolution possible using an immobilization device for live larvae is combined with the high temporal resolution of the light-sheet microscope. A microfluidic device was designed to be compatible with the physical constraints of the light-sheet microscope while simultaneously incorporating a 3D-segmental pinning immobilization channel to ensure minimized motion of the CNS of the larvae. The device achieved single-cell resolution (< 5 μm) of the whole brain of a live, intact larva. Z-stack images and time-series captures demonstrated the capability of the microscope to record volumetric images and high image acquisition rates of the live, intact larval CNS respectively. Thesis Master of Applied Science (MASc)