This thesis topic was selected in order to explore a connection between a passion for the beauty of gemstones and craftsmanship of jewelry making to provide a metaphor for making beautiful architecture. The direction of the thesis made manifest connections and similarities between integrating art, craft and making beautiful jewel pieces and architectural spaces for a building devoted to housing the kinds of precious items that would be reflected in a city such as Washington DC. The appreciation of outstanding factors in gems and jewel making would be analogous to the precision, design and level of detail explored in an architectural thesis which aims to celebrate these relationships by applying them to the design for a museum of jewels and gemstones for Rock Creek Park in Washington DC. / Master of Architecture

Job satisfaction is an important job-related attitude that has been linked to various outcomes for both the organization and its employees. In spite of this, researchers of the construct disagree about how job satisfaction is defined and measured. This study proposes the use of the Facet Satisfaction Scale, a new scale of measurement for job satisfaction that is based on more recent definitions of the construct. Reliability and preliminary predictive validity studies were conducted in order to determine the utility of this scale. Next steps in scale development are discussed.

Low back pain has a significant impact on global public health and economics. The bright facet sign (BFS), a common finding on magnetic resonance imaging (MRI) of the lumbar spine, is associated with low back pain. While degenerative joint disease (DJD) affects low back pain, its presence appears independent of the BFS at the disc and facet joints at the same spinal level. Increased BMI, considered a risk factor for DJD, has an inverse association with the BFS. The independent relationship of DJD and the BFS is poorly understood and may represent a previously unreported pain pathway. In this nested case-control quantitative study, based on an accepted conceptual framework, 350 lumbar MRI studies on symptomatic patients with historic and anthropomorphic data related to low back pain were analyzed using Spearman's Rho and Multivariate Logistic Regression to examine any associations between the BFS at 3 spinal levels and the independent variables age, race/ethnicity, physical activity, BMI, trauma, low back pain, and DJD. The findings revealed significant associations between the BFS and the duration of pain, age, and gender at 1 or more spinal levels, the BFS and BMI and degenerative facet disease (DFD) at all 3 spinal levels, and no association between the BFS and degenerative disc disease (DDD). These results, contrary to current medical constructs where BMI, DFD, and DDD are considered predictive of low back pain, facilitate an improved understanding of joint function and contribute to the current body of knowledge related to low back pain. An understanding of the BFS as it relates to DJD and low back pain will assist clinicians with the early detection of spinal degeneration and the mitigation of pain and suffering, contributing to positive social change.

Problem Statement: Nowadays, multiple choice (MC) tests are very common, and replace many constructed response (CR) tests. However, literature reveals that there is no consensus whether both test formats are equally suitable for measuring students' ability or knowledge. This might be due to the fact that neither the type of MC question nor the scoring rule used when comparing test formats are mentioned. Hence, educators do not have any guidelines which test format or scoring rule is appropriate. Purpose of Study: The study focuses on the comparison of CR and MC tests. More precisely, short answer questions are contrasted to equivalent MC questions with multiple responses which are graded with three different scoring rules. Research Methods: An experiment was conducted based on three instruments: A CR and a MC test using a similar stem to assure that the questions are of an equivalent level of difficulty. This procedure enables the comparison of the scores students gained in the two forms of examination. Additionally, a questionnaire was handed out for further insights into students' learning strategy, test preference, motivation, and demographics. In contrast to previous studies the present study applies the many-facet Rasch measurement approach for analyzing data which allows improving the reliability of an assessment and applying small datasets. Findings: Results indicate that CR tests are equal to MC tests with multiple responses if Number Correct (NC) scoring is used. An explanation seems straight forward since the grader of the CR tests did not penalize wrong answers and rewarded partially correct answers. This means that s/he uses the same logic as NC scoring. All other scoring methods such as the All or-Nothing or University-Specific rule neither reward partial knowledge nor penalize guessing. Therefore, these methods are found to be stricter than NC scoring or CR tests and cannot be used interchangeably. Conclusions: CR tests can be replaced by MC tests with multiple responses if NC scoring is used, due to the fact that the multiple response format measures more complex thinking skills than conventional MC questions. Hence, educators can take advantage of low grading costs, consistent grading, no scoring biases, and greater coverage of the syllabus while students benefit from timely feedback. (authors' abstract)

Approximately 80% of the population will experience low-back pain within their lifetime. Significant research efforts have focused on compressive loading as an injury mechanism that could lead to low-back pain and injury. However, the influence of shear loading, and its relationship to vertebral tissue tolerances as well as modulating factors for these tolerances have not been studied as extensively. The primary objective of this thesis was to produce a series of investigations that begin to determine the roles of different modulating factors such as posture, compression, bone density, bone morphology, and repetitive load magnitude on measured vertebral joint shear failure tolerances. The thesis comprises four independent studies using in vitro mechanical testing, imaging modalities, and finite element modeling. Each of the in vitro studies within this thesis used a validated porcine cervical model as a surrogate for the human lumbar spine. The first study employed in vitro mechanical testing to investigate the combined roles of flexion/extension postural deviation and compressive load on the measured ultimate shear failure tolerances. Peripheral quantitative computed tomography scans of the pars interarticularis and measurements of vertebral bone morphology were used in the second investigation along with in vitro mechanical testing to identify the morphological characteristics that can be used to predict ultimate shear failure tolerances. The influence of sub-maximal shear load magnitude on the cumulative shear load and number of loading cycles sustained prior to failure were investigated with in vitro mechanical testing in the third study. Finally, a finite element model of the porcine C3-C4 functional spinal unit was used to investigate the plausibility of hypotheses, developed from previous research and the findings of the first investigation for this thesis, surrounding alterations in measured ultimate shear failure tolerances as a function of changes in facet interaction. Results from the first investigation showed that there was no statistically significant interaction between postural deviation and compressive force on ultimate shear failure tolerance. However, ultimate shear failure tolerance was reduced (compared to neutral) by 13.2% with flexed postures, and increased (compared to neutral) by 12.8% with extended postures. Each 15% increment (up to a maximum of 60% of predicted compressive failure tolerance) in compressive force was met with an average 11.1% increase in ultimate shear failure tolerance. It was hypothesized that alterations in flexion/extension posture and/or compressive force altered the location for the force centroid of facet contact. These changes in the location of facet contact were hypothesized to produce subsequent changes in the bending moment at the pars interarticularis that altered the measured ultimate shear failure tolerance. The three leading factors for calculating of measured ultimate shear failure tolerance were the pars interarticularis length for the cranial vertebra, the average facet angle measured in the transverse plane, and cortical bone area through the pars interarticularis. A bi-variate linear regression model that used the cranial vertebra’s pars interarticularis length and average facet angle as inputs was developed to nondestructively calculate ultimate shear failure tolerances of the porcine cervical spine. Longer pars interarticularis lengths and facets oriented closer to the sagittal plane were associated with higher measured ultimate shear failure tolerances. Fractures observed in this investigation were similar to those reported for studies performed with human specimens and also similar to reported spondylolitic fractures associated with shear loading in humans. This provided additional evidence that the porcine cervical spine is a suitable surrogate in vitro model for studying human lumbar spine mechanics. Altered sub-maximal shear load magnitude create a non-linear decrease in both the number of cycles and the cumulative shear load sustained prior to failure. These findings suggested that estimates of cumulative shear load should assign greater importance to higher instantaneous shear loads. This was due to an increased injury potential at higher instantaneous shear loads. Cumulative load sustained prior to failure was used to develop a tissue-based weighting factor equation that would apply nonlinearly increased weight to higher shear load magnitudes in estimates of cumulative shear load. A finite element model of the porcine C3-C4 functional spinal unit was created, and simulations were performed using similar boundary conditions as the comparable in vitro tests, to assess the plausibility of the moment arm hypothesis offered within the first investigation of this thesis. Moment arm length between the force centroid of facet contact and the location of peak stress within the pars interarticularis was increased for flexed postures and decreased for extended postures. Alterations in moment arm length were larger for postural deviation than compressive force, suggesting a secondary mechanism to explain the observed increase in shear failure tolerance with higher compressive loads from the first investigation. One such possibility was the increase in the number of contacting nodes with higher compressive forces. Alterations in moment arm length were able to explain 50% of the variance in measured ultimate shear failure tolerances from the first study. Thus, the finite element model was successful in demonstrating the plausibility of moment arm length between the force centroid of facet contact and the pars interarticularis as a modulator of measured ultimate shear failure tolerance. This thesis has developed the basis for understanding how failure of the vertebral joint exposed to shear loading can be modulated. In particular, this thesis has developed novel equations to predict the ultimate shear failure tolerance measured during in vitro testing, and to determine appropriate weighting factors for sub-maximal shear forces in calculations of cumulative shear load. Evidence presented within this thesis also provides support for the long-standing moment arm hypothesis for modulation of shear injury potential.

Traveling-wave semiconductor optical amplifiers¡]TWSOAs¡^of symmetric and asymmetric multiple quantum wells¡]MQWs¡^have been implemented by using angled-facet structures. The asymmetric MQWs structures are designed to increase the wavelength range of the gain spectrum. The angled-facet structures, which can suppress gain ripple from FP resonance, are of 3mm-wide and 700mm-long ridge waveguides, and of different angles¡]q¡^at 3o, 5o, 7o, and 9o. From Marcuse¡¦s model, the calculation shows that the angled-facet structures have reflectivities lower than 10-4. We have also developed a single-trench process to fabricate the angled-facet TWSOAs. The l=1.55mm asymmetric structure, which shows a low epitaxial quality of large leakage current, is not suitable for SOA application. For the l=1.3mm asymmetric structure, the threshold current¡]Ith¡^at q=0o was 22.5mA, while at q=7o the Ith increased to 45mA. We have also measured the spectrum below threshold current. The differences between FP resonance peak and valley become smaller at larger q. We estimated that the reflectivity is about 0.2 at 5o. The results show that the reflectivity was decreased by angled-facet structure.

Approximately 80% of the population will experience low-back pain within their lifetime. Significant research efforts have focused on compressive loading as an injury mechanism that could lead to low-back pain and injury. However, the influence of shear loading, and its relationship to vertebral tissue tolerances as well as modulating factors for these tolerances have not been studied as extensively. The primary objective of this thesis was to produce a series of investigations that begin to determine the roles of different modulating factors such as posture, compression, bone density, bone morphology, and repetitive load magnitude on measured vertebral joint shear failure tolerances. The thesis comprises four independent studies using in vitro mechanical testing, imaging modalities, and finite element modeling. Each of the in vitro studies within this thesis used a validated porcine cervical model as a surrogate for the human lumbar spine. The first study employed in vitro mechanical testing to investigate the combined roles of flexion/extension postural deviation and compressive load on the measured ultimate shear failure tolerances. Peripheral quantitative computed tomography scans of the pars interarticularis and measurements of vertebral bone morphology were used in the second investigation along with in vitro mechanical testing to identify the morphological characteristics that can be used to predict ultimate shear failure tolerances. The influence of sub-maximal shear load magnitude on the cumulative shear load and number of loading cycles sustained prior to failure were investigated with in vitro mechanical testing in the third study. Finally, a finite element model of the porcine C3-C4 functional spinal unit was used to investigate the plausibility of hypotheses, developed from previous research and the findings of the first investigation for this thesis, surrounding alterations in measured ultimate shear failure tolerances as a function of changes in facet interaction. Results from the first investigation showed that there was no statistically significant interaction between postural deviation and compressive force on ultimate shear failure tolerance. However, ultimate shear failure tolerance was reduced (compared to neutral) by 13.2% with flexed postures, and increased (compared to neutral) by 12.8% with extended postures. Each 15% increment (up to a maximum of 60% of predicted compressive failure tolerance) in compressive force was met with an average 11.1% increase in ultimate shear failure tolerance. It was hypothesized that alterations in flexion/extension posture and/or compressive force altered the location for the force centroid of facet contact. These changes in the location of facet contact were hypothesized to produce subsequent changes in the bending moment at the pars interarticularis that altered the measured ultimate shear failure tolerance. The three leading factors for calculating of measured ultimate shear failure tolerance were the pars interarticularis length for the cranial vertebra, the average facet angle measured in the transverse plane, and cortical bone area through the pars interarticularis. A bi-variate linear regression model that used the cranial vertebra’s pars interarticularis length and average facet angle as inputs was developed to nondestructively calculate ultimate shear failure tolerances of the porcine cervical spine. Longer pars interarticularis lengths and facets oriented closer to the sagittal plane were associated with higher measured ultimate shear failure tolerances. Fractures observed in this investigation were similar to those reported for studies performed with human specimens and also similar to reported spondylolitic fractures associated with shear loading in humans. This provided additional evidence that the porcine cervical spine is a suitable surrogate in vitro model for studying human lumbar spine mechanics. Altered sub-maximal shear load magnitude create a non-linear decrease in both the number of cycles and the cumulative shear load sustained prior to failure. These findings suggested that estimates of cumulative shear load should assign greater importance to higher instantaneous shear loads. This was due to an increased injury potential at higher instantaneous shear loads. Cumulative load sustained prior to failure was used to develop a tissue-based weighting factor equation that would apply nonlinearly increased weight to higher shear load magnitudes in estimates of cumulative shear load. A finite element model of the porcine C3-C4 functional spinal unit was created, and simulations were performed using similar boundary conditions as the comparable in vitro tests, to assess the plausibility of the moment arm hypothesis offered within the first investigation of this thesis. Moment arm length between the force centroid of facet contact and the location of peak stress within the pars interarticularis was increased for flexed postures and decreased for extended postures. Alterations in moment arm length were larger for postural deviation than compressive force, suggesting a secondary mechanism to explain the observed increase in shear failure tolerance with higher compressive loads from the first investigation. One such possibility was the increase in the number of contacting nodes with higher compressive forces. Alterations in moment arm length were able to explain 50% of the variance in measured ultimate shear failure tolerances from the first study. Thus, the finite element model was successful in demonstrating the plausibility of moment arm length between the force centroid of facet contact and the pars interarticularis as a modulator of measured ultimate shear failure tolerance. This thesis has developed the basis for understanding how failure of the vertebral joint exposed to shear loading can be modulated. In particular, this thesis has developed novel equations to predict the ultimate shear failure tolerance measured during in vitro testing, and to determine appropriate weighting factors for sub-maximal shear forces in calculations of cumulative shear load. Evidence presented within this thesis also provides support for the long-standing moment arm hypothesis for modulation of shear injury potential.

M. Tech. / Abstract Purpose: The purpose of this study was to assess the effects of Diversified Chiropractic adjustments versus Flexion-Distraction Technique in the management and treatment of chronic Lumbar Facet Syndrome. Method: This study consisted of two groups, Group A and Group B, each consisting of 15 participants with chronic Lumbar Facet Syndrome. The participants were between the ages of 20 and 45 years. Potential candidates were examined and accepted based on the inclusion and exclusion criteria. Group A received Diversified Chiropractic Adjustments and Group B received Flexion-Distraction Technique to the lumbar facets. Procedure: Each participant was treated eight times over a period of four weeks. Before the commencement of treatment one, four and eight, the participants completed the Oswestry Low Back Pain and Disability Index questionnaire and the Visual Analogue Scale. A Digital Inclinometer was used to measure lumbar spine ranges of motion. Diversified Chiropractic adjustments were then administered to Group A based on the restrictions obtained during motion palpation. Flexion-Distraction Technique was administered to Group B based also on the restrictions that were obtained during motion palpation. Results: Objective statistically significant differences were noted on flexion and left lateral flexion ranges of motion before treatment, and clinically significant differences we noted on flexion and right lateral flexion after treatment, in favour of Group A. Subjective readings also showed statistically significant differences with regards to Oswestry Low Back Pain and Disability Index and Visual Analogue Scale in favour of both Group A and Group B. Conclusion: The results of the study indicate that both Diversified Chiropractic adjustments and Flexion-Distraction Technique have a positive effect on patients suffering from chronic Lumbar Facet Syndrome. However, Diversified Chiropractic adjustments proved to have a greater overall benefit compared to Flexion-Distraction Technique in the management and treatment of Lumbar Facet Syndrome.

M.Tech. / Purpose: The aim of this study was to compare the effects of Chiropractic adjustments to Muscle Energy Technique (MET) with regards to pain, disability and range of motion in the cervical spine. Method: Thirty participants, male or female between the ages of 18 and 55 years, diagnosed with cervical facet syndrome were used in the study. The thirty participants were randomly divided into two groups consisting of fifteen individuals each, ensuring equal male to female and age ratios. Group A received Chiropractic adjustment/s over the restricted joint/s to the cervical spine. Group B received MET to the cervical spine.The trial consisted of seven visits over a treatment period of three weeks, of which the first six visits the participants received treatment and the seventh visit served the purpose of obtaining the final data. The data was gathered on the first, fourth and seventh visits. The data was always gathered before the treatment was performed. Objective data consisted of measuring cervical spine range of motion with a CROM instrument. Subjective data was obtained by using the Numerical Pain Rating Scale (NPRS) and the Vernon-Mior Neck Pain and Disability Index. Results: The results indicated that Group A (Chiropractic adjustments) proved to be the most effective treatment protocol. Although the other treatment protocol, Group B (Muscle Energy Technique), also showed good results. Both subjective and objective results showed that although Group B produced statistically significant results, Group A showed the best results overall. Thus it was noted that in order to achieve a potentially lasting increase in range of motion and a decrease in pain and disability, the treatment protocol used for Group A should be the treatment of choice. Conclusion: It was concluded, based on the results, that Chiropractic adjustments was more effective than MET in the treatment of cervical facet syndrome. This conclusion is based on the results that Chiropractic adjustments was more effective in all the objective and all the subjective measurements. However, this does not rule out MET as a treatment for neck pain, because MET treatment did show improvements in cervical spine ROM and a decrease in pain, although not as efficiently as Chiropractic treatment.

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