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The pelvis and skull are frequently examined for the expression of sex-linked traits as are the humeral and femoral head dimensions. The second vertebra allows for rotation of the head, which is larger in males than in females. The axis is positioned close to other traits that have been shown to exhibit dimorphism, such as the mastoid process, gonial region, nuchal area, and the occipital protuberance. To explore which dimensions of the axis differ the most between females and males, and investigate its relationship to age, 149 individuals from the W.M. Bass Osteological Collection at the University of Tennessee, Knoxville were measured using 13 linear distances. The three age cohorts included 30-35, 50-55, and 70-75 years. The results indicate that all the traits show significant differences between the sexes. Using discriminant function analysis, predictive functions were created to estimate the sex of unknown individuals using 6 traits, 4 traits, 3 traits and 2 traits.

This work finds curious the relationships of figures bound by and revolving around a central axis. As this series of figures are elaborated by mathematical operations, the complex nature of their combination removes apparent identity and synthesizes a simultaneous presence which is difficult to name. The drawings serve as a form of notation, similar to sheet music. As notation they aim to find their voice in the physical world. The drawings search for relationships which are then made tangible so they can be studied in light and act as a model to continue working.

Mean-axis models of flight dynamics for flexible aircraft are being utilized more frequently in dynamics and controls research. The mean-axis equations of motion are traditionally developed with Lagrangian mechanics and are typically simplified using assumptions regarding the effects of elastic deformation. Although widely accepted in literature, the formulation and assumptions may be confusing to a user outside of the flight dynamics field. In this thesis, the equations of motion are derived from first principles utilizing Newtonian mechanics. Using this framework, the formulation offers new insight into the equations of motion and explanations for the assumptions. A three-lumped-mass idealization of a rolling flexible aircraft is presented as an example of the mean-axis equations of motion. The example is used to investigate the effects of common simplifying assumptions. The equations of motion are developed without any such assumptions, and simulation results allow for a comparison of the exact and simplified dynamics.

Total knee replacements (TKR) are one of the most frequently implanted medical devices, with over 600,000 procedures performed in the United States in 2012. In order to ensure TKR longevity, wear tests are frequently conducted on these implants prior to patient implantation. Variations in implant geometry, material, and surface treatments are all tested, however, TKR alignment may also play a role in the long-term success of the knee implant. When testing knee designs with complex tibial and femoral geometries it is essential that the implant be aligned as the implant manufacturers intended so as to best represent the function of the implant system. Although critical, a key alignment variable that is largely overlooked is femoral axis selection. Currently, femoral axis alignment is simply selected so as to minimize its effect on implant mechanics during walking simulation; a result that might completely misrepresent the implant designer's intent. The purpose of this study was to create a computational model to determine the effect of femoral axis selection on contact-point bearing migration prior to simulator fixation and examine trends in femoral axis selection based on implant geometry. Using 3D optical scans of seven femurs, 3Matic STL for model remeshing, and COMSOL Multiphysics for simulation this study recreated the single-axis rotation of each femoral component in a wear simulator. The lowest femoral contact point was then tracked between 0º and 120º flexion over four hundred possible femoral axes alignment options. The computational model was verified statistically and calculated the location of the ideal axes of rotation for all seven femurs. Reduction of P/D lowest contact-point translation during simulator flexion was found to be dependent on the range of flexion. Single-axis knee designs were found to exhibit a lower tolerance to varied femoral axes of rotation, but still maintained lower mean P/D displacements. Anterior/posterior translation patterns during simulator flexion were found to vary significantly with femoral axis selection. Interestingly, A/P translation patterns were more consistent between varying flexion axes in implants with multiple axes of curvature compared to single-axis designs. TKR alignment in single-axis simulators clearly affects proximal/distal and anterior/posterior lowest contact-point migration and thus possibly implant mechanics during functional testing. An implant that incorporates a geometry that is minimally affected by malalignment should enhance clinical outcomes and provide more consistent functional measures during simulation and use.

Located in rural Mount Laurel, Virgina, on the tobacco farm my mother was raised, this house grew from the use of memories as a design tool: my childhood memories not to mimic, rebuild, or remake, but to create new space for new memories. To create a space where, one day, my son could retreat and remember his childhood.

The architect, as a coordinator of complex conditions and different disciplines, has a role in the development of the master plan for the entire site, balancing technical innovation with appreciation for cultural inheritance. This thesis attempts to explore approaches to design decision making, as a response to a project's site, its history, and the larger cultural context. The above issues are investigated through the design of a multipurpose building at the east end of the Drillfield on the Virginia Tech campus in Blacksburg, Virginia. The building will form a "stage" to accommodate the daily life of the campus. In addition, the proposal was conceived to: a. emphasize both axial and radial geometric features of the site; b. redefine the edge of the oval Drillfield; c. create magnetic force between the proposed building and the existing War Memorial Chapel; d. translate the idea into tectonics.

The project is for the central building of a community center used by the communities of Blacksburg and Christiansburg. The building is a space configured as a hub that uses axes to determine entering, exiting and vertical movement. The hub configuration of the building is in concentric rings around the atrium in both space and materials. As materials were brought into the building, they enhanced the strong axial configuration and emphasized the layers surrounding the central hub space of the atrium. There are two pairs of axes in the building. The entrance axes are perpendicular to the faces of the building and provide lines of sight through it. They also establish the paths of entering and exiting the building. The diagonal axes regulate the vertical movement throughout the building.

Using the wartime reports produced by various field agents of the Office of Strategic Services (OSS), this dissertation attempts to rebut the currently hegemonic notion that the communist-led EAM/ELAS resistance organization was unprepared to militarily challenge the British and their anticommunist Greek clients for control of Greece after the German evacuation in late 1944. It also seeks to counter the related assumption that EAM/ELAS’s wide popularity after the end of the Axis occupation made a fight with the British unnecessary. The fact that conflict erupted anyway is cited by many historians sympathetic to EAM/ELAS as proof positive that EAM/ELAS’s supposedly hapless, naïve, and inexperienced leadership was manipulated into starting a revolution by the preternaturally clever British. The OSS reports from various parts of wartime Greece collected in this dissertation refute this supposition.By restoring historical agency to EAM/ELAS, this study also implicitly broaches the broader question of the origin of revolutionary violence. Despite the stated commitment of EAM/ELAS’s leaders to the concept of the Popular Front, the organization as a whole was responsible for conducting numerous ideological witch-hunts against its perceived domestic enemies during the war. In contrast, opposing the Axis appeared in many instances to be a secondary concern for many within the organization. Ultimately, this study argues that the beguiling utopian vision of a communist future for Greece created a kind of revolutionary imperative that dragged many members of EAM/ELAS, whether leaders or rank-and-file, along in its inexorable wake. Unfortunately for Greece, at the end of that path lay civil war.

An increase in circulating CCK induced by feeding protease inhibitors leads to growth of the exocrine pancreas, which is mediated at the acinar cell by the phosphatase calcineurin (CN). Here we examined activation of CN-regulated Nuclear Factor of Activated T-cells (NFATs) and the role of NFATs as transcriptional mediators of CN. Western blots and confocal imaging using isolated mouse pancreatic acini showed that CCK dose-dependently stimulated NFAT translocation into the nucleus. This shift correlated with CCK-induced activation of an NFAT-luciferase reporter and was blocked by CN inhibitors FK506, Cyclosporine A and overexpression of endogenous protein inhibitor of CN. Parallel changes took place in vivo. Pancreatic growth led to an increase in nuclear NFATs and subsequent activation of NFAT-luciferase in the pancreas, but not liver. These occurred in CN-dependent fashion as they were blocked by FK506. Activation of NFATs, well-known transcription factors, led us to examine genome-wide, CN-dependent transcriptional events. FK506 blocked expression of 38 genes, as confirmed by qPCR. The CN-dependent genes were linked to growth-related processes, while their promoters were enriched in NFAT and NFAT/API sites. Multiple novel NFAT targets were validated by ChIP. One of these, a CN feedback inhibitor Rcan1 (Regulator of Calcineurin 1), was induced >50 fold during 1--8h course of pancreatic growth and strongly inhibited (>99%) by FK506. We overexpressed Rcan1 in an inducible, acinar cell-specific fashion. Rcan1 inhibited CN-NFAT signaling, as shown by NFAT-luciferase reporter and qPCR. Most notably, the increase in exocrine pancreas size, protein/DNA content and acinar proliferation were blocked in Rcan1 expressing mice. In sum, our results document CCK-mediated and CN-dependent activation of NFATs. We profile adaptive pancreatic growth and delineate NFAT-regulated genes. This leads us to identify Rcan1 as an important new regulator of pancreatic growth and firmly establish that CN-NFAT signaling is required for this response.

At the crossing of a strong architectural edge and an axis line, it is necessary to articulate the intersection and acknowledge the moment. But what if, at the point of this intersection, other contextual factors work against the articulation? What if there is an opportunity to not only mark the intersection, but in doing so strengthen the edge condition, elevate the importance of the axis line and provide a celebrated threshold experience? This project looks at this very condition as it exists within the context of the Virginia Tech campus in Blacksburg, Virginia. At the intersection of the axis of symmetry for the campus and the building edge along Perry Street, there is no acknowledgment of this crossing. In fact, in its present condition, the intersection is beset by a breakdown in the edge condition and only a trace of the powerful axis line. In addressing the challenges that plague this existing condition, this project will seek to achieve four things with respect to the Virginia Tech campus, at large: 1. Articulate the termination point of the axis of symmetry for the campus by strengthening the pedestrian path that runs along the axis providing a clearly defined route to the Drill Field. 2. A redefinition of the edge along Perry Street, repairing the breech in the building wall and connecting the components that make up the edge. 3. Strengthen intersection of the edge and the axis/path line by developing a new pedestrian portal into the heart of campus thereby providing a formal entry point along an edge that currently does not articulate the entry points into campus. 4. Develop the architectural context within the site, bridging the divide between the architectural traditions of the campus core with the modernist vernacular of the Perry Street Edge.

My thesis is a human intervention into the tranquil and natural environment of Pandapas Pond and the Jefferson National Forest. Although the form of the intervention embraces the landscape and natural land formations, its purpose is to take the visitor along a path that translates the experience from one of participation to that of observation of the parkâ s surroundings. This is both an investigation of an architectural integration with the site and a partial separation of the inhabiter from his/her natural surroundings.

Architecture extends into a place through the manifestation of the human spirit and will. It should intensify that place and heighten the awareness of human existence. Upon entering into this higher realm of understanding of the self and place, one begins to find beauty in the created object inhabited. This architecture speaks of a higher intention of man, awakens his emotions, and urges his desires to not merely exist but to engage in the celebration of life. Architecture at the scale of the Town is a stage upon which the daily lives of the individual and the collective are framed, and the exchange of ideas, services, products and entertainment become the scenes of a play. The Town is an artifact of humanity. Through architecture, the Town should be a place where one can refine the mind, body, and soul - a place of fellowship and gathering. The focus of this thesis is to provide such a place for the Town of Floyd, Virginia.

In order to understand a sentence fully, one must understand its parts and the way they work. A complete sentence, in its most simple form, is a substantive with a verb in agreement. Additions to this sentence may include other substantives and verbs, but most additions are modifiers, either adjectival or adverbial. These modifiers should enhance the substantive and its verb, elevating their existence within the sentence. However, modifiers may also detract from the substantive and verb. This occurs when the substantive and verb become lost among the additions. A simple, easily understood complete sentence, i.e. a sentence containing only a substantive with a verb in agreement, becomes with the addition of too many modifiers that are not really necessary a foudryant expression that is difficult, although not impossible to diagram for the purpose of grasping the relationships between words that are, in their present state, convoluded by the addition of modifiers within and without clauses, to decipher. In other words, too many modifiers make a sentence difficult to understand. While the simple complete sentence is concise by its very nature, a concise sentence may contain much more than a substantive with verb. A concise sentence contains the essential and whatever else, if anything, to elevate the essential. Modifiers are not bad per se, but modifiers must remain just that: modifiers. They must be chosen carefully and remain secondary to the essential (provided that their primacy is not the intent). Modifiers and their use within a sentence are distinguishing factors between carefully crafted prose or poetry and misleading verbosity. The beauty of the concise sentence is its ability to express the most while using the least. The same can be true for architecture. For this thesis I looked to the substantive for establishing a connection between a project and the existing architecture of its site. [Vita modified March 5, 2012. GMc]

Rodent studies have suggested that activation of the hypothalamic-pituitary-adrenal (HPA) axis plays an important role in the expression of many drug-related behaviors. The purpose of the work presented in this thesis was to investigate the relationship between cocaine administration and HPA activity in rhesus monkeys, and to determine whether a role for glucocorticoids in cocaine-directed behavior could be demonstrated. In the first study, monkeys self administered intravenous cocaine on a fixed ratio 30, time out 10 min schedule of reinforcement. Cocaine produced a dose-dependent increase in HPA activity as a function of the number of cocaine injections. In the second study, this cocaine-induced rise in ACTH and/or cortisol levels was antagonized using pretreatment with the cortisol synthesis inhibitors, etomidate or ketoconazole, with the peptidic CRF antagonist astressin, and with the glucocorticoid-selective agonist, dexamethasone. Although each of these antagonists attenuated the cocaine-induced ACTH and/or cortisol increase, there was no concomitant change in either cocaine response-rate or the numbers of injections, that were earned. The third study evaluated the HPA effects of cocaine history and the contingency of cocaine delivery. ACTH and cortisol release were more dose-dependent and of a greater magnitude following response-contingent delivery than they were following non-contingent delivery. This difference may have been due to the monkeys having control over cocaine delivery, or to the amount of prior experience with cocaine. In the fourth study, the reinforcing efficacy of three synthetic glucocorticoids was measured. Most monkeys self administered dexamethasone on the first but not subsequent occasions. Only one of the seven monkeys reliably self administered all three glucocorticoids. It was concluded that cocaine increased HPA activity, although this increase in ACTH and cortisol was not necessary for the maintenance of cocaine self administration behavior in rhesus monkeys. Glucocorticoids were not reinforcing to the majority of monkeys in this study. Therefore, although cocaine administration led to an increase in HPA activity, glucocorticoids do not appear to play a role in ongoing cocaine-maintained behavior in rhesus monkeys.

To achieve the high precision required in contouring machining applications, advanced servo-control algorithms are continuously being sought. In the conventional approach, the servo-controller is designed for each moving axis independently, regardless of the motion of other axes. This uncoupled control approach may result in degradation of contouring performance, although good tracking performance for each individual axis is achieved. The principal objective of the thesis is to develop a control architecture called the cross-coupling controller (CCC) to improve contouring accuracy in multi-axis machining systems. The CCC method is based on constructing a contour-error model in real time and utilizing it in the determination of the control law that reduces or eliminates the contour error. Many researchers have implemented the CCC method and proven its superiority for linear cuts on two-axis systems. The existing CCCs, however, are not effective in dealing with nonlinear contours. Moreover, cross-coupling controllers have never been developed for more than two axes. The current research extends the CCC method to general nonlinear contours and general multi-axis systems. Two-axis, three-axis, and five-axis cross-coupling controllers for general nonlinear contours have been proposed in the thesis. The proposed 2-axis CCC includes an improved contour-error model and a PID control law. The 3-axis CCC extends the 2D contour-error model to a 3D model. For the 5-axis CCC, the elimination of the orientation error as well as the elimination of the contour error are chosen as the two controller objectives. Consequently, the 5-axis CCC consists of a contour-error model, an orientation-error model, and a PID control law. In addition to the proposed CCC method, other servo-control algorithms, such as PID-controller, ZPETC, and IKF methods, have been evaluated based on their abilities in error-source rejection and their limitations in machine tool control. The evaluation, which is supported by simulations and experiments, shows that the CCC method provides the best contouring accuracy. The proposed CCC architecture extends the design of interpolators in the following way: more complicated nonlinear contours can be accurately controlled by the CCC method, and therefore, we may design new interpolator algorithms to generate these contours, which are usually approximated by lines and/or circles on current CNC systems. Accordingly, multi-axis interpolators have been proposed, which are capable of interpolating general nonlinear contours.

High pressure is shown to give a valuable insight into the intrinsic c-axis resistivity of Highly Oriented Pyrolitic Graphite (HOPG). For the purpose of improving our understanding of the fundamental behavior of this technologically important material, additional forms of graphitic material such as Grafoil, Single Crystal Graphite (SCG) and polycrystalline natural graphite were explored for a comparative analysis. A novel technique utilizing a gasketed diamond anvil cell is described which permits four-probe resistivity measurements at pressures of up to 40 kbar and temperatures extending down to 2 K while maintaining the integrity of samples as fragile as graphite. The four-lead arrangement is designed to avoid contact and lead-wire resistances which might otherwise obscure the comparatively small resistance changes of interest typical of highly conductive materials. Our data on HOPG can be fitted well to a model describing conduction along the c-axis as composed of two components acting in parallel: an ordinary metallic one and a tunnelling conduction between crystallites. The total conductivity has been found to be a superposition of both conductivities, and their respective weights depend on the quality of the graphite material. This model accounts for the discrepancy in temperature dependence between HOPG and SCG and, in particular, the origin of the peak observed in the c-axis resistivity within polycrystalline forms of graphite. Samples of single crystal graphite of higher quality than previously reported have been examined and an asymptotic limit of T('2) has been found to govern the temperature dependence of the c-axis resistivity at low temperatures. Specimens of less perfect quality are found to have a temperature dependence of the form T('x), with x decreasing for lower quality samples.

Free-form surfaces and curves have been widely used in CAD systems to describe the part surfaces. The current method to machine these part surfaces generates, in off-line, a cutter location file (CL file) which describes the cutter path by a sequence of tool positions. The major disadvantage of this method is that there is a trade-off between machining time and surface accuracy which depends on the size of the CL file. However, a large CL file also increases the machining time since at each line the cutting tool accelerates and decelerates. To overcome these drawbacks, a real-time surface interpolator is proposed in this dissertation. The objective of this research is to develop new interpolation algorithms for CNC machine tools that will (i) produce smoother curves and surfaces and (ii) reduce machining time with using a smaller number of part-program statements. This comprises two achievements: (1) development of the real-time three-axis interpolator for 3-D surface machining and (2) development of the real-time five-axis interpolators for ruled surface machining (flank mills) and for convex surface machining (end mills). The real-time interpolator consists of (i) tool-path planning, (ii) trajectory planning, and (iii) inverse kinematics portions. It calculates new commands based on these three portions for the control loops during one sampling time. This makes the real-time interpolator capable of generating accurate references for axes motions and eliminating acceleration and deceleration steps during machining. Therefore, it produces smoother part surfaces and requires less machining time, compared with off-line approaches. With the new types of real-time interpolators, cutting a curve or surface requires only one g-code NC instruction. Therefore, the size of a CL file is significantly reduced. These new developed interpolators are implemented on a 5-axis CNC milling machine with demonstrated surfaces produced.

This dissertation has focused on the development of a three-dimensional, structured-light, multiple-axis laser scanning system and its modeling, calibration, and measurement uncertainty assessment techniques. A non-contact light-striping (structured-light) optical coordinate measuring machine (CMM) is developed. The configuration of the machine is multi-axis, capable of multi-degree-of-freedom three dimensional measurement. A system modeling approach based on a unique skewed frame representation without the use of pin-hole camera model assumption is presented. It is demonstrated that the extrinsic calibration matrix can be decomposed into two classes of transformations, one homogeneous and the other nonhomogeneous. The nonhomogeneous transformation between a Cartesian world frame and the non-Cartesian skewed sensor frame is studied. It is found that there are only four constraints in this transformation instead of the six constraints for common homogeneous coordinate transformations. The sensitivity of the dimensional deformation on the two skew angles is simulated. A new target-based method for the extrinsic calibration of the system is developed. The calibration is based upon the scanning of a physical artifact in the working volume of the measurement system whenever a change of position and/or orientation of the sensor occurs or during initial system setup. Based on the results of the modeling, a constrained optimization calibration algorithm is developed. Two types of targets are proposed: ball and tetrahedron. For ball target, due to distortion of the image, conjugate pair identification becomes non-trivial. A unique slice-interpolation algorithm is proposed. Through this calibration, the usually non-orthogonal skewed sensor coordinate system can be related to a Cartesian common world coordinate system. This allows correct interpretation of the measurement results. Experimental studies using both targets show that a micron level calibration accuracy can be achieved. The proposed system calibration procedure makes automated on-line calibration possible. An uncertainty propagation analysis has been performed on target-based extrinsic calibration of the system using first-order Taylor expansion for computation of uncertainties. Uncertainty transmission through each step of the calibration process is derived analytically. This makes on-line measurement uncertainty assessment possible. We have found that uncertainties of measurements are not homogeneous within the measurement volume. The results can readily be applied to uncertainty evaluation of any coordinate measuring device. Extensive statistical model testing has been performed. It is concluded that the analytical solutions are justified under normal machine condition.

In the present paper, an attempt is made to obtain the potential distribution in the case of two such charges, a source-sink combination, located on the axis of a bore hole drilled through an infinite, homogeneous medium.