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Articles 91 - 114 of 114
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Spatial And Deterministic Limits On Randomness, Matthew Davison
Spatial And Deterministic Limits On Randomness, Matthew Davison
Digitized Theses
The concept of Gaussian white noise has been very valuable in the application of stochastic differential equations to problems ranging from physics to finance. White noise has links with the diffusion equation, the solution of which gives the density of random walkers on a Euclidean space.;The use of white noise is not always appropriate in the study of random processes. In this thesis a new family of noise processes is defined. These "fractal walk" noise processes have connections with a "diffusion" equation in which the order {dollar}\gamma{dollar} of the time derivative takes on a continuous range of values between 0 …
Part I 2+2 Photocycloaddition Reactions Of N-Acylindoles With Alkenes Part Ii Photochemical Reactions In Supercritical Carbon Dioxide, Islet Brian Des
Part I 2+2 Photocycloaddition Reactions Of N-Acylindoles With Alkenes Part Ii Photochemical Reactions In Supercritical Carbon Dioxide, Islet Brian Des
Digitized Theses
Part I. Irradiation of 2-methyl, 3-methyl and 2,3-dimethyl substituted N-acylindoles in the presence of alkenes results in the formation of {dollar}\lbrack{dollar}2+2{dollar}\rbrack{dollar} cycloadducts which contain cyclobutane rings. The regiochemistry of the major product in all cases examined was found to be the result of initial bond formation from the 2-position of the N-acylindole to the less substituted terminus of the alkene. The quantum yield of cycloadduct formation was determined for the photocycloaddition reaction of the N-benzoyl derivatives with methyl acrylate and for the N-carboethoxy derivatives with 2-methylpropene. The reaction efficiency was found to be dependent on two factors. The first of …
Syntax-Directed Interpretation Of Visual Languages, Shane Denis Dunne
Syntax-Directed Interpretation Of Visual Languages, Shane Denis Dunne
Digitized Theses
Recent trends suggest that it will soon be practical to implement graphical user interfaces wherein a large part of the communication between human and computer will take the form of structured graphics, i.e., diagrams, notations, etc., which have come to be called "visual languages" in the literature. This thesis argues that implementation of such interfaces will be greatly facilitated by the development and use of syntax-directed translation methods for visual languages, and the embodiment of such methods in automated tools for application development, as has been done for compilers. An algebraic formalism to express syntax and semantics for visual languages …
Modulation Of Experimental Allergic Encephalomyelitis In The Sjl/J Mice By Cytokines And Anti-Cytokine Antibodies, Trang Thi Duong
Modulation Of Experimental Allergic Encephalomyelitis In The Sjl/J Mice By Cytokines And Anti-Cytokine Antibodies, Trang Thi Duong
Digitized Theses
Immunization with myelin basic protein in complete Freund's adjuvant resulted in only mild chronic-relapsing experimental allergic encephalomyelitis (EAE) with very low incidence in SJL/J mice, and no disease at all in A/J, BALB/c, C3H/HeJ, DBA/2, AKR and NZW mice. However, treatment of mice with anti-IFN{dollar}\gamma{dollar} (aIFN) monoclonal antibody (mAb) at the time of immunization determined severe disease in all those strains except AKR. Similarly, the passive induction of EAE in the SJL/J mice and in two of three resistant strains examined was significantly enhanced by aIFN mAb administration. In the SJL/J mice, administration of anti-interleukin 2 (aIL2) mAb had only …
Spectroscopic Properties Of Copper Binding To The Protein Metallothionein, Anna Rae Green
Spectroscopic Properties Of Copper Binding To The Protein Metallothionein, Anna Rae Green
Digitized Theses
Metallothionein (MT) is a low molecular weight protein found in the kidneys and livers of all mammals. Twenty of its 61 or 62 amino acid residues are cysteinyl residues, allowing the protein to act as an impressive chelating agent. Although it has been well established that mammalian MT binds seven M(II) (M = Cd(II), Zn(II), Hg(II)) ions tetrahedrally in two metal-thiolate clusters of the form M{dollar}\sb4{dollar}(S{dollar}\rm\sb{lcub}cys{rcub})\sb{lcub}11{rcub},{dollar} (the {dollar}\alpha{dollar} domain) and {dollar}\rm M\sb3(S\sb{lcub}cys{rcub})\sb9,{dollar} (the {dollar}\beta{dollar} domain), little is known about the structure of copper-containing metallothioneins. In this thesis, absorption, circular dichroism (CD) and emission spectroscopies and excited state lifetime data are …
Structural Studies On Silver(I) Metallothionein, Ziqi Gui
Structural Studies On Silver(I) Metallothionein, Ziqi Gui
Digitized Theses
Metallothioneins (MT) are a class of low molecular weight, cysteine rich proteins in almost all living things. These proteins have been found to bind a wide range of metals both in vivo and in vitro due to the unusually high cysteinyl sulfur content. The metallothioneins are believed to possess the ability to store and transport essential metals, such as Zn(II) and Cu(I), and also to detoxify toxic metals, such as Cd(II) and Hg(II). However, the precise physiological functions of these proteins still remain unclear to date. As silver(I)-metallothioneins have shown different stoichiometric ratios of Ag:MT from Zn(II)- and Cd(II)-metallothioneins in …
Evolutionary Dynamics At Two Loci Of The Human Genome As Assessed By Examination Of Nucleotide Sequence Diversity And Organization, Kathleen Allen Hill
Evolutionary Dynamics At Two Loci Of The Human Genome As Assessed By Examination Of Nucleotide Sequence Diversity And Organization, Kathleen Allen Hill
Digitized Theses
Accurate and comprehensive measurement of the extent and pattern of nucleotide diversity is necessary to refine theories on the dynamics of evolution. It is possible to determine the sequence of any genomic region for numerous individuals using the polymerase chain reaction (PCR) and associated techniques of DNA sequence analysis. The two regions of the human genome examined in this study were the third exon of the highly conserved (two major alleles) alcohol dehydrogenase, Adh2 locus and the second exon of the highly polymorphic (26 alleles) human leukocyte antigen, HLA-DQ{dollar}\beta{dollar}1 gene. Sequence information was determined from 25 individuals from Southwestern Ontario …
Using Model Systems To Study Rat Lens Membrane Damage During Cortical Cataract Formation, Fusun Kilic
Using Model Systems To Study Rat Lens Membrane Damage During Cortical Cataract Formation, Fusun Kilic
Digitized Theses
Cataract formation is a complex, multifactorial and multistep process: it is associated with cellular and biochemical changes in the lens. In the present work, steps in the pathway to cataract development were followed in vitro using two different reagents which induce cataract formation by two different mechanisms: elevated glucose (55.6 mM), as a model for in vivo diabetic cataractogenesis and an actin monomer-stabilizer, cytochalasin D (10{dollar}\sp{lcub}-5{rcub}{dollar} M, CD). Findings were utilized to classify and arrange the events in a common pathway and to focus on the mechanism of cataract production.;The development of cortical subcapsular opacity in cultured lenses was elucidated …
The Regulation Of A Type Iv Phosphodiesterase From L6 Myoblasts, A Thomas Kovala
The Regulation Of A Type Iv Phosphodiesterase From L6 Myoblasts, A Thomas Kovala
Digitized Theses
A potential role for cAMP in regulating the differentiation of myoblasts has lead to the examination of the components of the cAMP signalling system, in this case a cyclic nucleotide phosphodiesterase (PDE). A Type IV PDE isozyme was identified in L6 myoblasts using consensus sequence PCR primers, and its regulation by cAMP studied. Sequencing of RT-PCR products showed the presence of a Type IV PDE mRNA known as ratPDE 3.1. High levels of cAMP induced dramatic increases in the PDE mRNA levels as demonstrated by northern blot analysis. Run-off transcription experiments showed increased rates of transcription. L6 myoblasts which had …
The Quality Of Mother-Infant Interactions In Families At Risk For Maladaptive Parenting, Anne Krupka
The Quality Of Mother-Infant Interactions In Families At Risk For Maladaptive Parenting, Anne Krupka
Digitized Theses
Two related studies of mother-infant interactions during the first year were carried out. In Study 1, the process of attachment was examined from a developmental psychopathology perspective. In Study 2, an intervention program based on attachment theory was evaluated. The findings revealed a possible pathway to insecure attachment relationships, and provided a rationale for theory-based early prevention.;Study 1 was cross-sectional and longitudinal with 68 high-risk mother-infant dyads (mean maternal age, 17.9 years). A multimethod approach including home observations, questionnaires, interviews, and coding of key episodes, was used to measure cognitive and socioemotional characteristics of the infants and different aspects of …
Photosynthetic Acclimation To Light And Temperature: Excitation Pressure And Redox Sensing, Denis Philip Maxwell
Photosynthetic Acclimation To Light And Temperature: Excitation Pressure And Redox Sensing, Denis Philip Maxwell
Digitized Theses
Photosynthetic acclimation to low temperature has been studied extensively. However, since low temperature causes a preferential decrease in the rates of biochemical as compared to photochemical reactions, some alterations brought about by acclimation to low temperature may be the result of the light-harvesting apparatus absorbing more light energy than can be readily dissipated through photosynthesis. This possibility was investigated by using two species of green algae, Chlorella vulgaris and Dunaliella salina and the techniques of chlorophyll a fluorescence, O{dollar}\sb2{dollar}-evolution, protein electrophoresis and Western blotting, high performance liquid chromatography, RNA blot hybridization, and enzyme and metabolite assays. Compared to algae grown …
Depression And Vulnerability: The Role Of Mood And Depression History On Cognitive Processing, Scott Bradley Mccabe
Depression And Vulnerability: The Role Of Mood And Depression History On Cognitive Processing, Scott Bradley Mccabe
Digitized Theses
Cognitive theorists hypothesize the existence of a causal cognitive vulnerability for depression that exists as either a continuously observable trait-like difference (i.e., the main-effects model) or a latent factor observable only in interaction with life events or mood (i.e., the interaction effects model). The current investigation examined the main-effects model and one form of the interaction-effects model that emphasizes current mood as the activator of latent cognitive vulnerability, the Differential Activation Hypothesis (DAH). When primed by sad mood, vulnerable individuals purportedly process environmental information in a manner similar to currently depressed individuals, making them more vulnerable for depression.;Studies of cognition …
Computational Solution Of Inverse Problems With Simulated Annealing, Douglas John Moseley
Computational Solution Of Inverse Problems With Simulated Annealing, Douglas John Moseley
Digitized Theses
The examination of inverse problems represents a fascinating, diverse and difficult area of study. Almost any problem in mathematics, physics and engineering has an associated inverse problem. The method of quasi-solutions allows one to reformulate inverse problems as a function minimization involving the associated forward problem. The function to minimize is known as a penalty function or cost function and is defined as the least squares difference between some measured quantity and a quantity computed by the forward solver. This strategy avoids the need to construct the inverse operator. The forward problem is often well posed and can be solved …
Developmental Potential Of Rat Myoblast Lineages, Christopher Louis Pin
Developmental Potential Of Rat Myoblast Lineages, Christopher Louis Pin
Digitized Theses
Skeletal muscle consists of multinucleated fibres which are classified as slow (I) or fast (IIA, IIB, IIX) muscle fibre types which differ in their contractile properties and their expression of contractile protein isoforms. Individual muscles contain characteristic distributions of fibre types which can be identified based on their myosin heavy chain (MyHC) content. While classical studies have demonstrated that the fibre type composition of adult muscles can be altered by extrinsic factors (such as changes in the pattern of innervation), recent studies suggest that different fibre types may be formed from distinct myoblast lineages. The purpose of this study was …
The Mineralogy And Inorganic Geochemistry Of Coal And Combustion Products From The Mae Moh Mine, Thailand: Environmental Implications Of Resource Utilization, Brian R. Hart
Digitized Theses
The coals, associated sediments and combustion products, from the Tertiary, Mae Moh Lignite Mine Lampang, Thailand, have been investigated using XRD, XRF, NAA and SEM/EDS. The investigation is primary aimed at documenting the overall mineralogy and geochemistry of the coal and combustion products, in an attempt to briefly describe the local environmental impacts of resource utilization.;Ash content in composite run of mine samples in three important (J, K and Q) coal zones averages 44%. Ash in the power plant feed coal averages 41%. Dominant mineral phases in the zones include: detrital quartz, illite and kaolinite along with authigenic calcite and …
High Resolution And Wideline Nmr Studies Of Membrane Associated Molecules Involved In Signal Transduction, Alan Cavell Rigy
High Resolution And Wideline Nmr Studies Of Membrane Associated Molecules Involved In Signal Transduction, Alan Cavell Rigy
Digitized Theses
The primary focus of our investigations were centered around understanding the biochemical basis of the early events involved in signal transduction. Our work has involved two novel systems: (1) sphingolipid metabolites and (2) a synthetic peptide representing the transmembrane region of the human epidermal growth factor receptor (hEGFR).;Sphingolipid metabolites have emerged as physical modulators of many signalling pathways, including cell growth regulation, and signal transduction. N,N-({dollar}\sp2{dollar}H{dollar}\sb6{dollar}) -dimethylsphingosine and ({dollar}\sp2{dollar}H{dollar}\sb4{dollar}) -lysogalactosyl ceramide were produced by partial synthesis and studied via wideline {dollar}\sp2{dollar}H NMR, as a function of pH. Spectra of ({dollar}\sp2{dollar}H{dollar}\sb6{dollar}) -dimethylsphingosine identified that the molecule's orientation and behaviour are largely …
Maple Tools For Hydrodynamic Interaction Problems, Christopher Pratibha
Maple Tools For Hydrodynamic Interaction Problems, Christopher Pratibha
Digitized Theses
Several calculations of interactions between particles suspended in fluid are first described. In order to complete these calculations efficiently, several facilities that the present version of Maple does not provide are identified. These include the efficient computation of series solutions of ordinary differential equations, the management of large expressions and the convenient solution of polynomial equations in terms of a set of algebraic extensions dependent over the rationals. These facilities are developed and the calculations carried through to completion. A feature of the computations is the solution of ordinary differential equations to high accuracy by series methods. The mathematical and …
Feedback Control Mechanisms Regulating Breathing In Humans, Croix Claudette St
Feedback Control Mechanisms Regulating Breathing In Humans, Croix Claudette St
Digitized Theses
The respiratory system regulates alveolar ventilation (V{dollar}\sb{lcub}\rm A{rcub}{dollar}) almost exactly to the demands of the body so that the PCO{dollar}\sb2{dollar} and PO{dollar}\sb2{dollar} of the arterial blood are hardly altered, even during strenuous exercise or other types of respiratory stress. The feedback control of ventilation was studied in human subjects using the technique of dynamic end-tidal forcings to produce perturbations in end-tidal PCO{dollar}\sb2{dollar} (P{dollar}\sb{lcub}\rm ET{rcub}{dollar}CO{dollar}\sb2{dollar}) and end-tidal PO{dollar}\sb2{dollar} (P{dollar}\sb{lcub}\rm ET{rcub}{dollar}O{dollar}\sb2{dollar}) to stimulate the respiratory chemoreceptors.;The purpose of the first study was to investigate the interaction between ventilatory drives from the central (cR{dollar}\sb{lcub}\rm c{rcub}{dollar}) and peripheral (pR{dollar}\sb{lcub}\rm c{rcub}{dollar}) chemoreceptors using their different …
Epidermal Growth Factor Regulation Of Porcine Oocyte Maturation And Cumulus Cell Expansion In Vitro, Balwant Singh
Epidermal Growth Factor Regulation Of Porcine Oocyte Maturation And Cumulus Cell Expansion In Vitro, Balwant Singh
Digitized Theses
The overall objective of this study was to investigate the role in vitro of epidermal growth factor (EGF) in the regulation of both nuclear and cytoplasmic maturation of the porcine oocyte, and in the expansion of cumulus cells.;Studies aimed at the induction of oocyte maturation and cumulus expansion revealed that EGF is a potent stimulant of the resumption of meiosis in the oocyte and that the addition of FSH, but not LH, to EGF further enhances its effect on germinal vesicle breakdown (GVBD). Both estradiol-17{dollar}\beta{dollar} (E{dollar}\sb2{dollar}) and androstenedione (A{dollar}\sb4{dollar}) inhibited FSH-stimulated GVBD, but had no effect on EGF-stimulated GVBD, suggesting …
The Dynamic Behavior Of Guys And Guyed Masts In Turbulent Winds, Bruce F. Sparling
The Dynamic Behavior Of Guys And Guyed Masts In Turbulent Winds, Bruce F. Sparling
Digitized Theses
The dynamic response of guyed masts excited by wind turbulence is examined in this study using numerical methods. Specifically, the report addresses two main subject areas: the development of a simplified dynamic analysis method for guyed masts, and an investigation of the nonlinear dynamic response characteristics of guys and guyed masts.;A simplified patch load analysis method is proposed which reliably estimates the dynamic response of a wide variety of guyed masts. A series of static load patterns, or patch loads, are used to replicate the effects of wind gusts. Empirical scaling factors account for mast geometry and structural properties.;The proposed …
Traits, Situations, And Managerial Behaviour: Test Of A Trait Activation Hypothesis, Robert Preston Tett
Traits, Situations, And Managerial Behaviour: Test Of A Trait Activation Hypothesis, Robert Preston Tett
Digitized Theses
Results supporting the predictive validity of assessment centres (e.g., Gaugler, Rosenthal, Thornton & Bentson, 1987) are at odds with widely reported findings that behavioural consistency among assessment centre exercises is low (e.g., Sackett & Dreher, 1982). Lack of behavioural consistency raises doubts as to how assessment centres work. Drawing from principles of person-situation interactionism, a trait activation hypothesis is proposed to help explain the conflicting findings and direct development of valid simulation exercises. The hypothesis holds that the behavioural expression of a trait requires arousal of that trait by trait-relevant situational cues. Cross-situational consistency in behaviour is thereby conceived to …
Hardy-Type Inequalities On Weighted Orlicz Spaces, Jim Qile Sun
Hardy-Type Inequalities On Weighted Orlicz Spaces, Jim Qile Sun
Digitized Theses
This thesis is devoted to the study of integral operators of the form{dollar}{dollar}Kf(x)=\int\sbsp{lcub}0{rcub}{lcub}+\infty{rcub} k(x,t)f(t)dt{dollar}{dollar}on weighted Orlicz spaces. Weight characterizations are obtained for weighted modular inequalities, which generalize the results by Q. Lai and by H. Heinig and L. Maligranda for the Hardy operator. We also give results that parallel those by S. Bloom and R. Kerman for operators with more general kernels, but our results are valid under weaker conditions. Our results also have applications to the Stieltjes transformations and Hardy's inequalities for higher order derivatives.;Furthermore, the results above can be used to characterize the weights for modular inequalities when …
Programming Of Muscle Activity In Arm Movements In Relation To Force Requirements, Naznin Virji-Babul
Programming Of Muscle Activity In Arm Movements In Relation To Force Requirements, Naznin Virji-Babul
Digitized Theses
Analysis of the relationship between movement kinematics and muscle activity is a widely used approach for understanding how the nervous system formulates motor commands to produce movements. In planar single joint movements, phasic muscle activity is highly correlated with specific kinematic variables. Such correlations have not proven to be as direct in complex movements. The rules used by the nervous system in movement coordination are thus poorly understood. The purpose of this study was first, to examine kinematics, dynamics and electromyographic (EMG) activity during single and two-joint arm movements to discern the common planning strategies between these movements; and second, …
Finite Element Analysis Of Geometrically Nonlinear Laminated Composite Shell Structures, Bin Wang
Finite Element Analysis Of Geometrically Nonlinear Laminated Composite Shell Structures, Bin Wang
Digitized Theses
This thesis is concerned with static and dynamic analysis of linear and geometrically nonlinear laminated composite plate and shell structures by using the finite element method.;The emphasis has been on establishing a sound theoretical basis for the formulation of simple and efficient finite elements for large scale linear and geometrically nonlinear analysis of laminated composite plate and shell structures.;A series of simple three-node, six degree-of-freedom (DOF) per node, hybrid strain based flat laminated composite triangular shell finite elements (HLCTS) for linear analysis were developed. These elements were based on the degenerated three dimensional solid concept. The first order shear deformation …