Experimental and analytical research has been conducted to develop unified design procedures for eight extended end-plate moment connection configurations subject to cyclic/seismic loading. In addition, the suitability of extended end-plate moment connections for use in seismic force resisting moment frames was investigated. Eleven full-scale cyclic and nine monotonic extended end-plate moment connection tests were conducted. Design procedures for determining the required bolt diameter and grade, end-plate thickness, and column flange thickness were developed. The proposed design procedure utilizes a strong column, strong connection, and weak beam design philosophy. This forces the connecting beam to provide the required inelastic deformations through formation of a plastic hinge adjacent to the connection region. The proposed design procedure was used to make comparisons with ninety experimental tests conducted over the past twenty-six years. A limited finite element study was conducted to investigate the behavior of the column flange. The experimental results demonstrate that extended end-plate moment connections can be detailed and designed to be suitable for use in seismic force resisting moment frames. The proposed design procedure strength predictions correlated well with the results from ninety experimental tests. The limited finite element modeling conducted as a part of this study, correlated well with the strength predictions produced by the proposed design procedure. / Ph. D.

The response of light-frame timber shear walls to lateral forces is the focus of the dissertation. The objective of this study was to obtain performance characteristics of shear walls with various aspect ratios and overturning restraint via experimental testing and analytical modeling. Presented are the test data of monotonic and cyclic tests on fifty-six light-frame timber shear walls with aspect ratios of 4:1, 2:1, 1:1, and 2:3. Overturning restraint conditions represent engineered construction and conventional construction practices. The walls representative of the engineered construction were attached to the base by means of tie-down anchors and shear bolts. As opposed to engineered construction, conventionally built walls were secured to the base by nails or shear bolts only. The specimens were tested in a horizontal position with oriented strandboard (OSB) sheathing on one side. To obtain conservative estimates, no dead load was applied in the wall plane during the tests. The nail-edge distance across the top and bottom plates varied from 10 mm (3/8 in.) to 19 mm (3/4 in.). Twelve walls were repaired after the initial tests and re-tested. A mechanics-based model was advanced to predict the racking resistance of conventional multi-panel shear walls using simple formulae. The deflections of engineered and conventional shear walls were predicted using the energy method combined with empirical formulae to account for load-deformation characteristics of sheathing-to-framing connections and overturning restraint. The proposed formulae were validated through comparison with test results obtained during this study. The results of the study serve to further development of a mechanics-based methodology for design of shear walls accounting for various wall configurations and boundary conditions. / Ph. D.

The Parkinsonian-inducing neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and close structural analogs are the only known cyclic tertiary amines with good monoamine oxidase substrate properties. In addition to its substrate properties, MPTP is a weak mechanism-based inactivator of monoamine oxidase-B (MAO-B). In an attempt to exploit the special interactions between this cyclic tertiary allylamine and MAO-B, studies were initiated to develop novel mechanism-based inactivators of this flavoenzyme. Analogs of MPTP bearing a variety of functional groups at either N or the C(4) position have been synthesized and their interactions with purified MAO-B have been characterized. The substituents selected included functionalities which were considered potential sources of enzyme generated electrophilic or radical intermediates that might alkylate and inactivate the enzyme. None of the C(4)-substituted compounds displayed significant enzyme inhibitor properties while the 4-phenyl-I-propargyl analog was a good mechanism-based inactivator of MAO-B but not MAO-A. The 4-phenyl-1-propyl derivative showed significant turnover with MAO-B suggesting that previous reports regarding the lack of substrate properties of MPTP analogs bearing N-substituents larger than methyl must be viewed with caution. The MAO-A and B generated dihydropyridinium metabolite derived from 1-methyl-4-phenoxy-1,2,3,6-tetrahydropyridine was | observed to undergo rapid hydrolytic cleavage to yield phenol and 1-methyl-2,3-dihydropyridone, a chromophoric species that could be monitored spectrophotometrically. This reaction sequence was exploited to probe the active site of MAO-A and MAO-B with a variety of C(4)-aryloxytetrahydropyridine analogs bearing groups of different steric bulk on the aryloxy moiety. Almost all of the compounds displayed good to excellent substrate properties with MAO-A and MAO-B. In contrast to previous claims, these results argue that the active sites of both MAO-A and MAO-B will accommodate tetrahydropyridine derivatives bearing bulky groups at C-4. Consequently other factors are likely to contribute to substrate selectivity. The results described in this thesis provide evidence that a variety of disubstituted tetrahydropyridine derivatives are good to excellent substrates for MAO-A and MAO-B. The new insights gained in terms of structure-activity relationships with the compounds studied here should set the stage for the design of other tetrahydropyridine analogs with therapeutic potential. The localization of MAO-A and MAO-B in specific cell types within the nervous system makes particularly attractive the possibility of designing tetrahydropyridine based prodrugs which will undergo bioactivation in selected cells in the nervous system resulting in the liberation of the pharmacologically active species. / Ph. D.

The majority of residential construction and a significant portion of light commercial and industrial construction has been, and will continue to be light-framed timber construction. In recent years, innovations have surfaced to improve upon light-framed construction. Structurally insulated panels (SIPS) are gaining popularity due to their superior energy efficiency and ease of construction. Light-framed timber construction has proven to be trustworthy in high-wind and seismic regions due to its lightweight construction and numerous redundancies. Shear walls, along with floor and roof diaphragms, resist lateral loads in a timber structure. In the past, research has focused on the static racking performance of light-framed shear walls. More recently, research has been focused on the cyclic and dynamic performance of shear walls. To the author's knowledge, no other research is reported in the literature on the cyclic performance of SIPS shear walls. It is important to understand and quantify the monotonic and cyclic response of shear walls. In this study, twenty-three full-scale shear walls were tested under monotonic loading and sequential phased displacement cyclic loading. Four different wall configurations were examined. Monotonic and cyclic performance of the shear walls and monotonic and cyclic testing procedures are compared. Response of SIPS shear walls is also compared to the response of light-framed shear walls based on capacity, stiffness, ductility, energy dissipation, damping characteristics, and overall behavior. Results of this study will provide useful information regarding the performance of SIPS shear walls and similar systems subjected to static, cyclic, and dynamic lateral loads. / Master of Science

Dopamine and serotonin are two neurotransmitters known to both play a very important role in the human brain. For example, the death of dopamine producing neurons in a region of the brain known as the substantia nigra are known to cause the motor symptoms of Parkinson's disease. Also, many antidepressants are believed to work by increasing the extracellular level of serotonin in the brain. For the first time, it is now possible to measure the release of these two chemicals at sub-second time resolution in a human brain using a technique known as fast-scan cyclic voltammetry, for example from patients undergoing deep brain stimulation (DBS) electrode implantation surgery. In this work, we aimed to assess the feasibility of obtaining veridical dual measurements of serotonin and dopamine from substrates with mixtures of both chemicals. In the wet lab, data was collected on known concentrations of dopamine and serotonin and then used to make models capable of estimating the concentration of both chemicals from the voltammograms recorded in the patients. A method of linear regression known as the elastic net was used to make models from the wet lab data. The wetlab data was used to compare the performance of univariate and multivariate type models over various concentration ranges from 0-8000nM of dopamine and serotonin. Cross validation revealed that the multivariate model outperformed the univariate model both in terms of the linear correlation between predictions and actual values, and pH induced noise. The pH induced noise for the univariate model was 3.4 times greater for dopamine and 4.1 times greater for serotonin than the multivariate model. Raman spectroscopy was also investigated as a possible alternative to fast-scan cyclic voltammetry. Raman spectroscopy could have several benefits over fast-scan cyclic voltammetry, including the ability to chronically implant the measurement probe into a patient's brain and make observations over a long period of time. Raman spectroscopy data was collected on known concentrations of dopamine to investigate its potential in making in vivo measurements, however this data collection failed. Therefore, simulations were made which revealed the potential of the elastic net algorithm to determine the Raman spectra of several neurotransmitters simultaneously, even when they are in mixtures and the spectra are obstructed by the noisy background. The multivariate type model outperformed the univariate type model on Raman spectroscopy data and was able to predict dopamine with an error of 805nM RMS and serotonin with an error of 475nM RMS after being trained on concentrations smaller than 5uM of both dopamine and serotonin. In addition, the original Raman spectra of both neurotransmitters was extracted from the noise and reproduced very accurately by this method. / Master of Science

The mean field analysis of stochastic dynamical system allows us to gain insight into the qualitative features of their complex behavior, as well as quantitative estimates of certain aspects of their coarse-grained properties. As such, it usually furnishes a first front in approaching new dynamical systems and informs us about their stability landscape in the absence of fluctuations among other things. A knowledge of this landscape can be a valuable tool in model building for describing real world systems and provides a guiding principle for a justifiable choice of form and model parameters. In this work, we contribute to this analysis for two generic classes of high-dimensional models that possess a cyclic symmetry in the network that specifies their stochastic dynamics at the microscopic level. Our analysis is carried out in a manner that can be readily adapted for the mean field analysis of further generalized models that possess this symmetry. Moreover, in the second class of these models, we propose a new basic process that can change the stability landscape of an existing model and, as such, endow us with potential alternatives to model systems with robust biodiverse regimes. / Ph. D.

Although clays are generally considered stable materials under seismic conditions, recent failures initiated in clay layers after earthquakes have emphasized the need to study the cyclic and post-cyclic behavior of these materials. Moreover, if strength loss as a result of cyclic loading were to occur in the material comprising the dam and/or dam foundation, the consequences of failure could be substantial. The objective of this study is to evaluate the effect of plasticity characteristics, mineralogical composition, and accumulated energy on the cyclic behavior, post-cyclic shear strength and the degradation in shear strength due to cyclic loading in normally consolidated clays. Seventeen soil samples prepared in the laboratory from kaolinite, montmorillonite, and quartz were tested using static and cyclic simple shear apparatuses. In addition, the results of cyclic simple shear tests on twelve natural samples were provided by Fugro Consultants, Inc. in Houston, TX. Using the results, cyclic strength curves were developed to represent 2.5%, 5% and 10% double amplitude shear strains. These curves were used to examine the influences of mineralogical composition, plasticity characteristics and shear strain on the cyclic resistance of soil samples. A power function was used to represent the cyclic strength curves. The samples were found to become increasingly resistant to cyclic loading as the plasticity index increased. Moreover, the soils with montmorillonite as the clay mineral were noted to have consistently higher cyclic resistances than the soils with kaolinite as the clay mineral. By examining the power functions, it was found that the cyclic strength curve approaches linearity as the plasticity index increases in soils having kaolinite as the clay mineral. However, the opposite trend is observed in soils having montmorillonite as the clay mineral. The study shows that the post-cyclic shear strength increases with increasing plasticity index. Moreover, the post-cyclic shear strengths of soils with montmorillonite as the clay mineral were significantly higher than the post-cyclic shear strengths of soils with kaolinite as the clay mineral. The degradation in shear strength due to cyclic loading appeared unaffected by mineralogy, but a greater reduction in strength was noted with decreasing plasticity index. The post-cyclic shear strength was also found to reduce as the number of cycles required to cause 10% double amplitude shear strain increased. The energy approach considering the accumulated energy per unit volume in the soil mass as a result of cyclic loading was also utilized in this study. The results from the energy approach were independent of the cyclic wave form, but were still dependent on the amplitude of the cyclic load used during the testing. An increase in the amplitude of the cyclic loading function results in a decrease in the accumulated energy per unit volume. Furthermore, an increase in the liquid limit and/or plasticity index of the soils containing kaolinite as the clay mineral shows an increase in the accumulated energy, whereas an increase in plasticity of the soils containing montmorillonite as the clay mineral results in a decrease in the amount of accumulated energy. In both types of materials, the amount of accumulated energy per unit volume is found to increase with increasing double amplitude shear strain. Relationship between the ratio of post-cyclic undrained shear strength to the baseline undrained shear strength and the accumulated energy is also determined. / Ph. D.

Laboratory tests were performed to investigate the liquefaction susceptibility of uncemented calcareous sands. A series of isotropically consolidated undrained monotonic and cyclic triaxial tests were performed using the Playa Santa sand from Porto Rico. Playa Santa sand is a poorly graded calcareous clean beach sand composed of angular particles with large intra-granular voids. A series of consolidated undrained triaxial tests were performed with the Playa Santa sand remolded to a variety of relative densities and consolidated under a range of confining pressures. In addition, cyclic triaxial tests were performed at a confining pressure of 100 kPa and three sets of relative densities (20%, 40% and 60%). Generation of excess pore pressure under different levels of cyclic loading was established. As a result, relationships were developed to relate the number of cycles required for triggering of liquefaction to cyclic stress ratio. It was seen that the Playa Santa sand was less susceptible liquefaction than quartzitic sands of the same relative density remolded and tested under similar conditions. / Master of Science

Tsoi Sze Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 82-104). / Text in English; abstracts in English and Chinese. / Tsoi Sze Man. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Overview of study --- p.1 / Chapter 1.2 --- Cerebellum --- p.2 / Chapter 1.2.1 --- General Structure of cerebellum --- p.3 / Chapter 1.2.2 --- Cell types of cerebellar cortex --- p.4 / Chapter 1.2.2.1 --- Basket cells --- p.5 / Chapter 1.2.2.2 --- Stellate cells --- p.6 / Chapter 1.2.2.3 --- Purkinje cells --- p.6 / Chapter 1.2.2.4 --- Granule cells --- p.7 / Chapter 1.2.2.5 --- Golgi cells --- p.8 / Chapter 1.2.2.6 --- Unipolar brush cells --- p.9 / Chapter 1.2.2.7 --- Deep cerebellar nuclear neurons --- p.11 / Chapter 1.2.3 --- The neuronal circuitry of the cerebellum --- p.12 / Chapter 1.2.4 --- Cerebellar function --- p.14 / Chapter 1.3 --- Cyclic nucleotide-gated (CNG) channels --- p.16 / Chapter 1.3.1 --- Molecular characterization of CNG channels --- p.16 / Chapter 1.3.2 --- Functional properties of CNG channels --- p.19 / Chapter 1.3.3 --- Expression of CNG channels in brain --- p.21 / Chapter 1.3.4 --- CNG channel and neuronal plasticity --- p.23 / Chapter 1.4 --- Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels --- p.26 / Chapter 1.4.1 --- Molecular characterization of HCN channels --- p.27 / Chapter 1.4.2 --- Functional properties of HCN channels and Ih current --- p.29 / Chapter 1.4.3 --- Modulation by cyclic nucleotides --- p.31 / Chapter 1.4.4 --- Expression of HCN channels in brain --- p.33 / Chapter 1.4.5 --- Physiological roles of Ih current in central nervous system --- p.35 / Chapter 1.5 --- Aims of study --- p.38 / Chapter Chapter 2 --- Material and Methods --- p.39 / Chapter 2.1 --- Immunohistochemistry Experiments --- p.39 / Chapter 2.1.1 --- Animal preparation --- p.39 / Chapter 2.1.2 --- Tissue preparation --- p.39 / Chapter 2.1.3 --- Primary and secondary antibodies --- p.40 / Chapter 2.1.4 --- Immunofluroescence staining --- p.41 / Chapter 2.1.5 --- Confocal laser scanning microscopy and data processing --- p.41 / Chapter 2.2 --- Whole cell patch clamp recordings --- p.42 / Chapter 2.2.1 --- Brain slice preparation and identification of the cerebellar Purkinje neurons --- p.42 / Chapter 2.2.2 --- Whole cell voltage- and current-clamp recordings --- p.43 / Chapter 2.2.3 --- Drug solutions and delivery --- p.44 / Chapter 2.2.4 --- Statistical analysis --- p.45 / Chapter Chapter 3 --- Expression of Various Cyclic Nucleotide-Gated (CNG) Channel Subunits in Rat Cerebellum --- p.46 / Chapter 3.1 --- Introduction --- p.46 / Chapter 3.2 --- Results --- p.46 / Chapter 3.2.1 --- Immunoreactivity of CNGA1 in cerebellum --- p.46 / Chapter 3.2.2 --- Immunoreactivity of CNGA2 in cerebellum --- p.47 / Chapter 3.2.3 --- Immunoreactivity of CNGA3 in cerebellum --- p.47 / Chapter 3.3 --- Discussion --- p.48 / Chapter Chapter 4 --- Expression of Various Hyperpolarization-Activated Cyclic Nucleotide-Gated (HCN) Channel Subunits in Rat Cerebellum --- p.53 / Chapter 4.1 --- Introduction --- p.53 / Chapter 4.2 --- Results --- p.53 / Chapter 4.2.1 --- Immunoreactivity of HCN 1 in cerebellum --- p.53 / Chapter 4.2.2 --- Immunoreactivity of HCN2 in cerebellum --- p.55 / Chapter 4.2.3 --- Immunoreactivity of HCN3 in cerebellum --- p.55 / Chapter 4.2.4 --- Immunoreactivity of HCN4 in cerebellum --- p.55 / Chapter 4.3 --- Discussion --- p.55 / Chapter Chapter 5 --- Electrophysiological Recordings of Cyclic Nucleotide-Gated Ionic Conductance in Rat Cerebellar Purkinje Neurons --- p.59 / Chapter 5.1 --- Introduction --- p.59 / Chapter 5.2 --- Results --- p.59 / Chapter 5.2.1 --- Effect of cyclic nucleotides on the membrane potential of cerebellar Purkinje neurons --- p.59 / Chapter 5.2.2 --- Ionic conductance of the cyclic nucleotide-induced inward current --- p.61 / Chapter 5.2.3 --- The mechanism of the cyclic nucleotide-induced inward current --- p.61 / Chapter 5.2.3.1 --- Site of action --- p.62 / Chapter 5.2.3.2 --- Involvement of CNG channels and HCN channels --- p.63 / Chapter 5.2.3.3 --- Involvement of protein kinase A (PKA) and protein kinase G (PKG) --- p.65 / Chapter 5.2.3.4 --- Involvement of inwardly rectifying potassium (Kir) channels and transient receptor potential (TRP) channels --- p.65 / Chapter 5.2.4 --- Effect of cyclic nucleotides on Ih current in Purkinje neurons --- p.67 / Chapter 5.3 --- Discussion --- p.68 / Chapter Chapter 6 --- Concluding remarks References --- p.78 / References --- p.82

In this thesis, the dynamical system is used as a function on afinite group, to show how states change. We investigate the'numberof cycles' and 'length of cycle' under finite groups. Using grouptheory, fixed point, periodic points and some examples, formulas tofind 'number of cycles' and 'length of cycle' are derived. Theexamples used are on finite cyclic group Z_6 with respectto binary operation '+'. Generalization using finite groups ismade. At the end, I compared the dynamical system over finite cyclic groups with the finite non-cyclic groups and then prove the general formulas to find 'number of cycles' and 'length of cycle' for both cyclic and non-cyclic groups.