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Injury, instrumentation, or surgery may change the functional biomechanics of the spine. Spinal fusion, the current surgical treatment of choice, stabilizes the spine by rigid fixation, reducing spinal mobility at the cost of increased stress at adjacent levels. Recently, alternatives to spinal fusion have been investigated. One such alternative is total disc replacements. The current generation of total disc replacements (TDRs) focuses on restoring the quantity of motion. Recent studies indicate that the moment-rotation response and axis of rotation, or quality of motion (QOM), may have important implications in the health of adjacent segments as well as the health of the surrounding tissue of the operative level. This dissertation examines the use of compliant mechanism design theory in the design and analysis of spinal arthroplasty devices. Particularly, compliant mechanism design techniques were used to develop a total disc replacement capable of replicating the normal moment-rotation response and location and path of the helical axis of motion. Closed-form solutions for the device's performance are proposed and a physical prototype was created and evaluated under a modified F1717 and a single-level cadaveric experiment. The results show that the prototype's QOMclosely matched the selected force-deflection response of the specified QOM profile. The use of pseudo-rigid-body modeling to evaluate the effects of various changes on motion at adjacent segments is also investigated. The ability to model biomechanical changes in the spine has traditionally been based on animal models, in vitro testing, and finite element analysis. These techniques, although effective, are costly. As a result, their use is often limited to late in the design process. The pseudo-rigid-body model (PRBM) developed accurately predicted the moment-rotation response of the entire specimen and the relative contribution of each level. Additionally, the PRBM was able to predict changes in relative motion patterns of the specimen due to instrumentation.

The current study examines the roles of expectancy disconfirmation and pseudo-altruistic behaviors as communication strategies to increase receiver compliance, and their effects on perceptions of the source, including credibility and likeability ratings. While adding to the previous research, this investigation examines the effects on compliance when pseudo-altruistic practices are employed in a sales situation. Additionally, subjects’ compliance responses in the treatment groups are analyzed for relationships between compliance and several possible mediators, including participant’s evaluations of the source, and feelings of obligation and guilt. A focus group was held to discuss the face validity of the scenarios. Additionally, a pilot study was conducted to verify the operationalization of the independent variable, and to reveal any items that needed to be modified before the actual study was conducted. 141 undergraduate students were assigned to one of six treatment groups, and responded to the scenario and questionnaire. Five-point Likert type scales were used for the source factor and compliance items, and seven-point semantic differential scales were used for the items which measured source perceptions. Additionally, an optional open-ended item was employed for subjects to explain the motives behind their decisions. Analysis of the data showed that participants in the pseudo-altruistic treatment conditions were more likely to return to Store or Dealership A, or tipped the server more than usual. They also rated the source as more expert and of higher character in the treatment groups that the neutral, control groups. This increase in compliance was consistent across all three scenarios. Regression analyses also revealed that source factors including concern, helpfulness, unexpected behavior, expertise, character, honesty, and likeability predicted 26% of the compliance variance. In conclusion, subjects were more likely to comply in the pseudo-altruistic treatment condition, regardless of the scenario. Their compliance is attributed to feelings of liking and higher ratings of the source, which facilitated reciprocal altruism and benefited the salesperson or server for their selfless behavior.

This study examines the analyzes the 2010 National Tea Party Convention in order to determine whether the Tea Party Movements’ rhetoric is unique from the rhetoric employed by previously studied movements. The study forwards the concept of a pseudo-movement: a movement that appears radical, but has normative, procedural goals.

abstract: Pseudo-steady state (PSS) flow is an important time-dependent flow regime that quickly follows the initial transient flow regime in the constant-rate production of a closed boundary hydrocarbon reservoir. The characterization of the PSS flow regime is of importance in describing the reservoir pressure distribution as well as the productivity index (PI) of the flow regime. The PI describes the production potential of the well and is often used in fracture optimization and production-rate decline analysis. In 2016, Chen determined the exact analytical solution for PSS flow of a fully penetrated vertically fractured well with finite fracture conductivity for reservoirs of elliptical shape. The present work aimed to expand Chen’s exact analytical solution to commonly encountered reservoirs geometries including rectangular, rhomboid, and triangular by introducing respective shape factors generated from extensive computational modeling studies based on an identical drainage area assumption. The aforementioned shape factors were generated and characterized as functions for use in spreadsheet calculations as well as graphical format for simplistic in-field look-up use. Demonstrative use of the shape factors for over 20 additional simulations showed high fidelity of the shape factor to accurately predict (mean average percentage error remained under 1.5 %) the true PSS constant by modulating Chen’s solution for elliptical reservoirs. The methodology of the shape factor generation lays the ground work for more extensive and specific shape factors to be generated for cases such as non-concentric wells and other geometries not studied. / Dissertation/Thesis / Masters Thesis Chemical Engineering 2017