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Human cardiovascular adaptations to microgravity include decreased plasma volume, exercise capacity, baroreflex function as well as decreased orthostatic tolerance upon return to a gravity environment. Several countermeasures have been proposed and tested, although currently none have been developed to prevent post-spaceflight orthostatic intolerance (OI). Artificial gravity (AG) generated by short-radius centrifugation (SRC) has been proposed as a countermeasure to OI as well as other cardiovascular alterations. Methods: Fifteen men and fourteen women underwent three weeks of daily (5 days a week) exposure to intermittent (1.0 to 2.5 Gz) artificial gravity on a 1.9m human powered centrifuge (HPC) at the NASA Ames Research Center. Half the subjects exercised (active) to power the HPC while half rode passively (passive). A combination head-up tilt (HUT) and lower body negative pressure (LBNP) test was used to determine orthostatic tolerance before and after training. Oscillatory LBNP (OLBNP) was used at seven frequencies (0.01 to 0.15 Hz) for two minutes each to assess the dynamic responses of the cardiovascular system to orthostatic stress, before and after AG training. Results: Training improved overall tolerance in the group of subjects by 13% (pandlt;0.05); men were more tolerant than were women (pandlt;0.05); and active subjects were more improved than passive subjects (pandlt;0.05). Mechanisms of improvement appear to be through decreased total peripheral resistance (TPR) and increased stroke volume after training, and increased responsiveness of TPR to fluid shifts (faster changes in TPR to changes in calfcircumference [CC] and OLBNP after training). There was no change in spontaneous baroreflex sensitivity (BRS, calculated by sequence method) or number of sequences per number of heart beats (NNS), although BRS analysis did indicate that stimulation to the cardiac baroreceptors during 1.0 Gz and 2.5 Gz centrifugation was no different than supine control and 70?? HUT, respectively. Taken together, these results suggest that AG training improved tolerance through training of local mechanisms in the peripheral vasculature, or extrinsic control of peripheral vascular resistance, rather than through changes of autonomic control of heart rate.

Carbonatites are carbonate-rich magmatic rocks that are rare and of great relevance for our understanding of crustal and mantle processes. Although found on all continents and in settings ranging from Archaean to present-day, their deeper plumbing system is still poorly understood. Therefore, the main goal of this thesis is to broaden the existing knowledge of carbonatite systems, often limited to surface geological observations, by providing depth constraints using a number of geophysical methods and petrophysical measurements. The Alnö alkaline and carbonatite complex in central Sweden was chosen for this purpose. Data from three reflection seismic lines, ground gravity and magnetic measurements are presented. These data are complemented by a series of petrophysical measurements, including ultrasonic velocities, density, magnetic bulk susceptibility, anisotropy of magnetic susceptibility (AMS), and magnetic remanence, to aid in the interpretation of the geophysical data. The reflection seismic data indicate a solidified saucer-shaped fossil magma chamber at about 3 km depth. Caldera-style volcanism, constrained by surface geological observations, provides a plausible scenario to explain the emplacement of the complex, suggesting that carbonatite magmas have been stored, transported and erupted in a similar manner to known emplacement mechanisms for silicic calderas, although these are compositionally different. The AMS data from most of the carbonatite sheets in Alnö show a strong degree of anisotropy and oblate-shaped susceptibility ellipsoids. A set of syn- and post-emplacement processes that may control the AMS signature is evaluated based on the dataset. Overprinting of the primary flow patterns by processes related to sheet closure at the terminal stage of magma transport may explain the AMS observations. A complementary study using 3D inversion of ground gravity and aeromagnetic data was then carried out to better delineate the 3D internal architecture of the complex. Resulting models indicate a depth extent of the complex to about 3-4 km, consistent with the interpretation of the reflection seismic data. The modelling results of a ring-shaped magnetic anomaly observed in the Klingefjärden bay adjacent to Alnö Island further suggest that the complex may extend laterally about 3 km towards the north.

The conductor of a large instrumental ensemble is constantly confronted with the task of detecting and correcting rhythm and pitch performance errors in daily rehearsals. The purpose of this investigation was to design a computer-assisted instruction program for error detection skills development and then evaluate this program's effectiveness in training beginning conductors to identify rhythm and pitch errors within 2-, 3-, 4-, and 5-voice synthesized music excerpts from the existing band literature. The transfer of error detection skills from synthesized to acoustic sounds also was explored indirectly by virtue of utilizing taped excerpts from wind band performances to assess error detection skills.Subjects (N=24) in this study were drawn from the pool of undergraduate instrumental music education majors at Ball State University and were randomly assigned to control treatment groups prior to the administration of the Acoustic Error Detection Skills Inventory. Following this pretest, the treatment group used the Computer Error Detection Skills Program for approximately eight hours during an eight week treatment period. At the end of the treatment period, and control and treatment groups were administered the Acoustic Error Detection Skills Inventory posttest.The data were analyzed using a series of one-way, repeated measures analyses of variance (ANOVA) to assess pretest to posttest changes in subjects' scores on the Acoustic Error Detection Skills Inventory. Composite scores (reflecting general skill in error detection) improved significantly for the treatment group (p = .007), while the pretest to posttest gain for the control group was not statistically significant (p = .232). These results suggest that the Computer Error Detection Skills Program was effective in enhancing subjects' rhythm and pitch error detection skills and the viability of using synthesized sound sources for training was confirmed.The following recommendations were made: (1) Jazz directors need to do more listening to jazz music, (2) band directors who direct jazz programs should join IAJE, (3) jazz ensembles shouldtheir own improvisational skills, and rehearse in the fall, (4) jazz ensemble directors should develop (5) jazz ensemble directors should have their students sing their parts during rehearsals for increased learning efficiency and retention. / Human Performance Laboratory

As a part of a project designed to mimic a Space Shuttle flight (LMS), eight healthy males completed 17 d of -6° head down tilt bedrest to assess the in vivo torque velocity relationship of the calf muscle group and the cardiorespiratory responses to supine cycling exercise. The subjects age, height, and weight were 42.7 ±8.1 y, 182.3 ±6.5 cm, and 82.2 ±12.1 kg, respectively. Testing was completed prior to bedrest (CON), on bedrest days 2 & 3 (BR 1), 8 & 9 (BR2), and 13 & 14 (BR3), as well as recovery days 3 & 4 (R1), and 7 & 8 (R2). Maximal plantar flexion force production at seven angular velocities (0, 30, 60, 120, 180, 240, 300'- s-1) was unchanged (P>0.05) during bedrest and recovery. Muscle biopsy specimens obtained from the soleus before and on day 17 of bedrest showed no change (P>0.05) in muscle fiber composition, muscle fiber area, capillary to fiber ratio, or capillary density. Citrate synthase activity decreased 21% (P<0.05) from 122.1 ±7.8 to '97.1 ±5.1 µmol -min-1 • g dry wt-1, while phosphorylase activity was unchanged (P>0.05). VO2max (L • min-1) was decreased (P<0.05) from CON (3.24 ±0.20) during BR1 (2.99 ±0.17; -7.3%), BR2 (3.00 ±0.17; -7.1%), BR3 (2.92 ±0.20; -9.0%), and R1 (3.02 ±0.20; -6.6%), but was not different (P>0.05) than CON by R2 (3.13 ±0.19; -3.3%). Maximal heart rate and ventilation did not change (P>0.05) from CON during bedrest or recovery. Initial changes in VO2max (BR1) were significantly correlated with fluid balance during bedrest day 1 (r=0.91, P<0.05). These data suggest that the testing protocols in this investigation may be sufficient to attenuate functionally significant changes in muscle morphology and strength during 17 d of simulated microgravity. The results also suggest that the time course for changes in VO2max are not linear and are related to the initial changes in body fluid volumes. / Human Performance Laboratory

Falkenberg area is located in southwest Sweden formed in the Sveconorwegian orogen and contains an extremely complex geological structure. Multiple geophysical datasets have been acquired and together with available petrophysical information, models corresponding to the subsurface geological structures were generated. The collected data comprise ground magnetic, AMT (Audio Magnetotelluric) and RMT (Radio Magnetotelluric) data. The available airborne magnetic and ground gravity data acquired by the Geological Survey of Sweden (SGU) as well as the reflection seismic section from a study made by Uppsala University further aids in obtaining substantially improved interpretation of the geometry of the structures along the AMT profile. The principal objective of this profile was to delineate and map the possible deformation zone crossed by the profile. The AMT study was expected to complement existing geophysical data and improve existing interpretations. The Ullared deformation zone contains decompressed eclogite facies rocks. The presented results were obtained by comparison of different geophysical methods along the profile. The susceptibility model and resistivity model show that eclogites have higher resistivity and susceptibility than the surrounding structures. However use of the Occam type of inversion on the AMT data, makes the resistivity model smoother than the susceptibility model and as a results it is difficult to estimate the dip of the structures. The AMT profile and the seismic section show the same dip direction (NE) for the eclogite bearing structures although due to the smoothing in the AMT model the dips seen in the seismic section cannot be recovered in the resistivity model.

This thesis begins by introducing the concept of a rigid quasilocal frame (RQF) as a geometrically natural way to define an extended system in the context of the dynamical spacetime of general relativity. An RQF is defined as a two-parameter family of timelike worldlines comprising the worldtube boundary of the history of a finite spatial volume with the rigidity conditions that the congruence of worldlines is expansion-free (the ``size'' of the system is not changing) and shear-free (the ``shape'' of the system is not changing). We demonstrate that this frame exists in flat and arbitrary curved spacetimes and, moreover, exhibits the full six motional time-dependent degrees of freedom we are familiar with from Newtonian mechanics. The latter result is intimately connected with the fact that a spatial slice through the RQF - having a two-sphere topology - always admits precisely six conformal Killing vector (CKV) fields (three boosts and three rotations) associated with the action of the Lorentz group on a two-sphere. These CKVs, along with the four-velocity of observers on the RQF, are then used to quasilocally define the energy, momentum, and angular momentum inside an RQF without relying on the pre-general relativistic practice of appealing to spacetime symmetries. These quasilocal definitions for energy, momentum, and angular momentum also involve replacing the local matter-only stress-energy-momentum (SEM) tensor with the Brown-York matter plus gravity boundary SEM tensor. This allows for the construction of completely general conservation laws which describe the changes in a system in terms of fluxes across the boundary. Furthermore, since an RQF is a congruence with zero expansion and shear only relevant fluxes appear in these conservation laws - that is, fluxes due merely to changes in the size or shape of the boundary are eliminated. These resulting fluxes are simple, exact, and quantified in terms of operationally-defined geometrical quantities on the boundary and we show that they explain at a deeper level the mechanisms behind gravitational energy and momentum transfer by way of the equivalence principle. In particular, when we accelerate relative to a mass, the energy changes at a rate proportional to our acceleration times the momentum (and we propose an exact gravitational analogue of the electromagnetic Poynting vector to capture this idea). Similarly, the momentum of that object changes at a rate proportional to our acceleration times the energy. This new insight has fascinating consequences for how we should understand everyday occurrences like a falling apple - that is, the change in energy of the apple involves frame dragging while the change in momentum involves extrinsic curvature effects near the apple. Our naive general relativistic intuition tells us that these quantities should be so tiny that they should be negligible and, indeed, they are tiny but they are multiplied by huge numbers to give rise to macroscopic effects. This is how general relativity universally explains the transfer of energy and momentum but we needed rigid quasilocal frames to uncover this beautiful property of nature. Using the RQF formalism we also investigate a variety of specific problems. In particular, while looking at time-dependent rotations we discover that the reason Ehrenfest's rigid rotating disk paradox has gone unsolved for so long is that rotation introduces a subtle non-locality in time. By this we mean that, in order to maintain rigidity while undergoing time-dependent rotation, one needs to know, not only the instantaneous rotation rate, but the entire history of the motion. This makes it impossible to keep a volume of observers rigid but is doable with an RQF. We also consider RQFs in the small-sphere limit to derive many of our results and one example with particularly interesting consequences involves Bell's spaceship accelerating through an electromagnetic field. Here, we show that the change in electromagnetic energy inside the spaceship is made up of two pieces: the usual electromagnetic Poynting flux accounts for half the change while the gravitational Poynting vector equally contributes to make up the other half. This means that electromagnetism in flat spacetime generically does not tell you what is actually going on. Rather, the curvature due to the electromagnetic field necessitates a fully general relativistic treatment to get the whole story. We also use the RQF linear momentum conservation law in the context of stationary observers and fields to derive, for the first time, an exact fully general relativistic analogue of Archimedes' law. In essence, this law demonstrates that the weight of the matter and gravitational fields contained in a finite region of space is supported by the stresses (buoyant forces) acting on the boundary of that region. Furthermore, in a post-Newtonian approximation, we derive a simple set of quasilocal conservation laws which describe non-relativistic systems bound by mutual gravitational attraction. In turn, we use these laws to obtain expressions for the rates of gravitational energy and angular momentum transfer between two tidally interacting bodies - that is, the tidal heating and tidal torque - without the need to define unphysical pseudotensors. Moreover, the RQF approach explains these transfers of energy and momentum again, not as the difference of forces acting on a tidal bulge, but instead more fundamentally in the language of the equivalence principle in terms of ``accelerations relative to mass''. Throughout this work we demonstrate that the RQF approach always gives very simple, geometrical descriptions of the physical mechanisms at work in general relativity. Given that this approach also includes both matter and gravitational energy, momentum, and angular momentum and does not rely on spacetime symmetries to define these quantities, we argue that we are seeing here strong evidence that the universe is actually quasilocal in nature. We are really deeply ingrained with a local way of thinking, so shifting to a quasilocal mindset will require great effort, but we contend that it ultimately leads to a deeper understanding of the universe.

Quantum Field Theory (QFT) provides the essential background for formulating the standard model of elementary particles and, moreover, practically all other theories attempting to explore the physical laws of nature at the sub-atomic level. One of the main observables in QFT are the scattering amplitudes, physical quantities which encode the information of the scattering process of particles. Accordingly, having authentic, well-defined and feasible prescriptions for the calculations of amplitudes is of huge importance to theoretical physicists. Actual calculations show that the text-book prescription, the Feynman method, besides in general being very cumbersome also hides some of the beautiful mathematical features of amplitudes. The last decade has seen tremendous efforts and achievements to improve such calculations, particularly in supersymmetric gauge theories, which have also led to better understanding of QFT itself. Among the known physically and mathematically interesting quantum field theories is perturbative gravity and its supersymmetric version, N=8 supergravity- much less understood than gauge theory. Following the developments in gauge theory, this dissertation mainly aims at exploring scattering amplitudes in gravity as a quantum field theory, using the modern approaches to QFT. The goal is not only to improve our understanding of gravity amplitudes by applying part of the known modern methods of calculations to it but also to introduce and develop new ones.

An expansive panel of well exposed (periglacial) strata of the Upper Kaza Group permitted a detailed study of the stratal architecture of proximal basin floor deposits in the Neoproterozoic Windermere turbidite system. Detailed stratigraphic and petrographic analyses identified six lithofacies: poorly-sorted, clast-rich mudstone (F1), thin-bedded siltstone and mudstone (F2), thick-bedded, massive sandstone (F3), medium-scale, cross-stratified sandstone (F4), mudstone-clast breccia (F5), and medium-bedded turbidites (F6). The spatial distribution of these facies identify five architectural elements: heterolithic feeder channel deposits (FA1), thin-bedded intralobe turbidites (FA2), terminal splay deposits (FA3), distributary channel deposits (FA4), and isolated scours (FA5). FA 1-4 are genetically related and form the basic building blocks of large-scale basin floor depositional lobes. FA 5, which is isolated to the stratigraphic top of the study area, is interpreted to have formed in a base-of-slope setting, and its superposition on FA 1-4 suggests the long-term progradation of the Windermere turbidite system.