No description available.

Solar flare soft x-ray emission from 0.5 Å to 8.5 Å was observed during 1967-68 by U.S. Naval Research Laboratory Bragg crystal (LiF and EDDT) spectrometers aboard the OS0-4 satellite and also by NRL broad band ionization detectors aboard the OG0-4 satellite. In this work, instrumental parameters for the LiF crystal spectrometer based on experimental values have been determined and used in the data analysis. The source continuum spectra between 1 Å and 3.8 Å have been obtained for selected flares from OS0-4 spectrometer scans. As these spectra are each affected by time variations over 14 minutes, they are compared with the thermal continuum (free-free and free-bound) spectra predicted in the following manner. The instantaneous electron kinetic temperature and emission measure (equal to the product of the square of the electron number density and the total volume) of the flare plasma are determined from the available OG0-4 broad band data. The expected continuum flux is calculated by using these parameters. The comparison shows that there is good agreement between 2 Å and 3.8 Å. Thus it has been concluded that reliable values of the average electron temperature can be determined from the OG0-4 flare data. The earlier wavelength assigrunent and line identification list published by Meekins et al (1970, Solar Physics 13, 198) has been substantially improved in this work by separately summing a large number of OS0-4 spectrometer scans of the flaring and active sun. All identified wavelengths are found to agree with the more accurate theoretical valuesto within + 0.01 Å. Identifications of several weak lines as due to hydrogen-like and helium-like ions of chlorine and phosphorus have also been suggested. The temporal behaviour of selected ion line intensities (due to Fe, Ca, Si, S, Al, and Mg) indicates that they follow the expected temperature variations during the flare. The total continuum emission in the 0.5 to 3 Å and the 1 to 8 Å broad band segments has been determined from OG0-4 data for 21 flares. In doing this, a simple and approximate method of converting the total emission based on the gray body approximation (in which the OG0-4 data are reported) to one based on the thermal continuum spectrum has been developed. This study shows that the total energy lost in the 0.5 to 8 Å soft x-ray channel is of the order of 10²⁸ to 10³⁰ ergs depending on the Hα importance of the flare (from sub- to class 2); it is also shown that this energy is comparable with that emitted in higher wave length segments estimated by other authors. / Graduate

Higher levels of self-regulatory efficacy (SRE) appear to be helpful to those individuals with arthritis attempting to continue to be regularly physically active during an arthritis flare. Arthritis flares are presumed to represent a greater challenge to being physically active than usual arthritis symptoms but within-participant comparisons of pain intensity and SRE when considering flare status (flare vs no flare) have not been examined. While SRE has been compared between those who meet recommended levels of moderate to vigorous physical activity (MVPA) during an arthritis flare, persistence with MVPA has not been examined in arthritis. Finally, pain acceptance has been associated with differential levels of MVPA in arthritis but has not been examined in the circumstances of a flare and persistence with MVPA. Thus, 4 objectives were advanced. Primary objective one was to explore within-participant comparisons of pain intensity and SRE during a flare or usual symptoms. Primary objective two was to compare those meeting and not meeting MVPA guidelines in terms of their persistence and SRE. Secondary objective one was to explore whether persistence with MVPA in a flare could be predicted by pain acceptance and SRE, and secondary objective two was to examine psychosocial variables ability to predict MVPA volume prospectively over 4 weeks. To pursue these objectives, 53 adults with arthritis were recruited to complete an online survey with potential follow-up questions completed online four weeks later. Concerning objective one, participants reported SRE to overcome arthritis barriers (SRE-AB) and to schedule/plan MVPA (SRE-SP) in two contexts; in a flare and in the absence of a flare. Pain intensity was reported in the same flare contexts. 2 x 2 ANOVAs were conducted comparing both SRE measures and pain between those that met MVPA guidelines or not, and within-participants in a flare or usual symptoms. A MANOVA was iii conducted between MVPA groups on SRE and persistence to satisfy primary objective two. Secondary objective one was examined using a hierarchical multiple regression (HMR) with pain acceptance and SRE-SP predicting persistence. A second HMR was conducted attempting to predict MVPA at time 2 (T2) using SRE and persistence. Results of the 2 x 2 ANOVAs were that SRE (AB and SP) and pain intensity were significantly different within-groups (p < .001) such that SRE was lower and pain was higher in a flare than not in a flare. Only SRE-SP was different between MVPA groups (p < .05). The MANOVA identified only SRE-SP in a flare as significantly different between MVPA groups (p < .05). Pain acceptance did predict persistence in block 1 of the HMR (p < .01) but when SRE-SP was added, SRE-SP was the only significant predictor (p < .001). Results of the second HMR indicated that of all the psychosocial variables entered, only SRE-SP in a flare significantly predicted T2 MVPA (p < .01). Findings suggest that, as active individuals with arthritis feel less efficacious to be active and higher pain intensity during a flare, a flare does indeed represent an increased challenge to MVPA adherence. Interestingly, pain intensity did not differ between MVPA groups while SRE-SP did, supporting that greater SRE beliefs are required in challenging circumstances. Pain acceptance did initially predict persistence until SRE-SP was added to the model. SRE may have consumed the variance in the model not because of pain acceptance’s inability to predict but rather due to the high correspondence between SRE and persistence measures. Finally, SRE-SP predicted MVPA volume prospectively, further supporting the utility of high SRE when attempting to adhere to MVPA during the increased challenge posed by an arthritis flare.

Estágio realizado na Refinaria do Porto da Petrogal e orientado pelo Eng.º Fernando Morgado Lopes / Tese de mestrado integrado. Engenharia Química. Faculdade de Engenharia. Universidade do Porto. 2009

Thesis (Ph. D.)--University of California, San Diego, 1984. / Vita. Includes bibliographical references (leaves 141-142).

Thesis (Ph. D.)--University of California, San Diego, 1984. / Vita. Includes bibliographical references (leaves 141-142).

Thesis (Ph. D.)--University of California, San Diego, 1982. / Vita. Includes bibliographical references (leaves 136-139).

No description available.

Thesis (Ph. D.)--University of Hawaii at Manoa, 1995. / Includes bibliographical references. / Microfiche. / xii, 158 leaves, bound ill. 29 cm

Thesis (PhD)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: Petrus Martens. Includes bibliographical references (leaves 160-170).