Real and complex number systems

Thesis (M.A.)--University of Illinois, 1908.Typescript.Bibliography: [2] leaves at end

Habitat Associations of the Golden-Winged Warbler in Honduras

The global population of the Neotropical migrant Golden-winged Warbler (Vermivora chrysoptera) has declined steadily over the past fifty years. While factors influencing this decline have been well researched on the breeding grounds, little is known about the distribution and habitat requirements of this warbler on its stationary non-breeding range. Recent efforts to quantify the non-breeding habitat requirements of this warbler have focused on Colombia and Costa Rica, though the species ranges as far north as the Yucatan Peninsula, Mexico. To address the gap in knowledge from the northern portion of the non-breeding range, I conducted 80 serial point-count surveys targeting Goldenwinged Warblers at eight field sites in Honduras, Central America. I found that Goldenwinged Warblers occupy a greater variety of habitats than previously recognized, including pine-oak forest and semi-deciduous broadleaf forest. I also documented habitat associations that have not been observed in other parts of the non-breeding range with respect to elevation, rainfall, and spatial segregation by sex. These results demonstrate the need to consider the entire non-breeding range in conservation planning, as Goldenwinged Warbler habitat associations appear to vary regionally

The urgent need for career preview: Student expectations and graduate realities in music and dance

Unlike the work available in many creative disciplines, musicians and dancers have the possibility of full-time, company-based employment; however, participants far outweigh the number of available positions. As a result, many graduates become ‘enforced entrepreneurs’ as they shape their work to meet personal and professional needs. This paper first explores the career projections of 58 music and dance students who were surveyed in their first week of post-secondary study. It then contrasts these findings with the reality of graduate careers as reported by five of that cohort four years later. In contrast with the students’ overwhelming focus on performance roles, the graduate cohort reported a prevalence of portfolio careers incorporating both creative and non-creative roles. The paper characterises the notion of a performing arts ‘career’ as a messy concept fraught with misunderstanding. Implications include the need to heighten students’ career awareness and position intrinsic satisfaction as a valued career concept

The implementation of chlamydia screening: a cross-sectional study in the south east of England

Background England's National Chlamydia Screening Programme (NCSP) provides opportunistic testing for under 25 year-olds in healthcare and non-healthcare settings. The authors aimed to explore relationships between coverage and positivity in relation to demographic characteristics or setting, in order to inform efficient and sustainable implementation of the NCSP. Methods The authors analysed mapped NCSP testing data from the South East region of England between April 2006 and March 2007 inclusive to population characteristics. Coverage was estimated by sex, demographic characteristics and service characteristics, and variation in positivity by setting and population group. Results Coverage in females was lower in the least deprived areas compared with the most deprived areas (OR 0.48; 95% CI 0.45 to 0.50). Testing rates were lower in 20 1324-year-olds compared with 15 1319-year-olds (OR 0.69; 95% CI 0.67 to 0.72 for females and OR 0.67; 95% CI 0.64 to 0.71 for males), but positivity was higher in older males. Females were tested most often in healthcare services, which also identified the most positives. The greatest proportions of male tests were in university (27%) and military (19%) settings which only identified a total of 11% and 13% of total male positives respectively. More chlamydia-positive males were identified through healthcare services despite fewer numbers of tests. Conclusions Testing of males focused on institutional settings where there is a low yield of positives, and limited capacity for expansion. By contrast, the testing of females, especially in urban environments, was mainly through established healthcare services. Future strategies should prioritise increasing male testing in healthcare settings

Proficiency in Storytelling

Proceedings of the Sixth Annual Meeting of the Berkeley Linguistics Society (1980), pp. 120-13

Musculoskeletal Modeling of the Pelvis and Lumbar Spine During Running

Musculoskeletal modeling provides an alternative to in-vivo characteristics that are difficult to directly measure for movements such as running, especially for trunk muscles and joints. The full-body-lumbar-spine (FBLS) model by Raabe and Chaudhari, 2016 is an OpenSim model created for simulations of jogging. The lifting full-body (LFB) model by Beaucage-Gauvreau et al., 2018 is an adaptation of the FBLS created for estimating spinal loads during lifting. PURPOSE: Determine validity of the FBLS and LFB models in simulating pelvis and lumbar spine kinematics during running. METHODS: Inverse Kinematics were executed using experimental data for the FBLS and LFB models. To obtain the 3D motion data, 5 runners ran on a treadmill at self-selected jogging pace (2.6±0.2 m/s). Axial rotations at the pelvis segment and for the sum of lumbar motion (L1-L5 intervertebral disc joints) were calculated from marker data, and the range of motion (ROM) averaged for the experimental data and each computational model. RESULTS: FBLS and LFB models had the same relative movement patterns as the experimental data. However, the ROM for both models differed from the human data. For the experimental data, the average ROM was 33.6 ± 15.6° for total lumbar rotation and 24.7 ± 12.3° at the pelvis. The ROM for the pelvis was 17.97±6.87° and 19.22±7.63° for the LFB and FBLS models, respectively. The lumbar ROM was 29.53±5.46° and 18.39±10.56° for the LFB and FBLS models, respectively. The differences in ROM could be because the experimental data used a multi-segmented torso and a rigid lumbar spine marker model, whereas the OpenSim models utilized a rigid torso (lumped thoracic and cervical vertebrae, ribcage, scapulae, and head) with a coupled lumbar spine. The average maximum RMS across all participants was 0.05 ± 0.004 cm for both LFB and FBLS models. CONCLUSION: The LFB model was created for lifting simulations but provides a better simulation of running motion at the lumbar and pelvis than the FBLS model, potentially due to the LFB model having a 3-DOF joint at T12/L1 and linear kinematic coupling constraints to distribute the net trunk motion across the six intervertebral joints (T12-L5). The ROM differences at the L5/S1 could potentially be corrected with a multi-segmented torso model. Both models have potential for simulating axial rotation of the pelvis and lumbar spine during running.https://digitalcommons.odu.edu/gradposters2021_engineering/1001/thumbnail.jp

Trunk Kinematics Using Musculoskeletal Modeling During Range of Motion Tasks

A spine model can be used to predict post-spinal fusion motion needed to perform physical activities in individuals with scoliosis. Full body lumbar spine (FBLS) model (Raabi et al., 2016) allows for modeling lumbar spine and pelvis movement and was validated for jogging. However, like other existing adult spine models, FBLS model does not allow for a motion providing thoracic and spine. Purpose: To adapt the FBLS model for simulating thoracic, lumbar and pelvis motion during trunk rotation in all 3 planes of motion. Methods: Since T12-L1 in FBLS model is designed as a dependent joint (axial rotation analogous to L5-S1), the constraints between torso and lumbar spine were removed and modified to allow three-dimensional motion for T12-L1. Inverse kinematics (IK) were calculated for the adjusted model. Range of motion (ROM; max-min) at T12-L1 and L5-S1 joints were compared to the experimental data of 3 healthy adults during maximal flexion-extension, lateral bending, and axial rotation. Results: Experimental data showed 64.4±3.8° and 30.0±7.2° of flexion-extension, 40.8°±4° and 10.9°±4.7° of lateral bending, and 29.7°±3.6° and 13.9°±1.1° of axial rotation for T12-L1 and L5-S1, respectively. While IK result revealed 2.4°±0.1 and 16.3°±2.0 of flexion-extension, 7.9°±0.7 and 1.5°±0.4° of lateral bending, and 32.7°±0.6° and 12.9°±4° of axial rotation for T12-L1 and L5-S1, respectively. T12-L1 joint motion did not corroborate in sagittal and frontal planes where a disconnection between thoracic and lumbar segments was noted. Subsequently, experimental data was significantly greater than IK for sagittal and frontal planes from FBLS and matched best for transverse plane for both joints. Conclusion: The existing FBLS model shows reasonable promise to be adapted for different ROM tasks in transverse plane motion to accurately model trunk motions greater than those expected in jogging.https://digitalcommons.odu.edu/gradposters2021_healthsciences/1010/thumbnail.jp

Global Cosmological Parameters Determined Using Classical Double Radio Galaxies

A sample of 20 powerful extended radio galaxies with redshifts between zero and two were used to determine constraints on global cosmological parameters. Data for six radio sources were obtained from the VLA archive, analyzed, and combined with the sample of 14 radio galaxies used previously by Guerra & Daly to determine cosmological parameters. The results are consistent with our previous results, and indicate that the current value of the mean mass density of the universe is significantly less than the critical value. A universe with $\Omega_m$ of unity is ruled out at 99.0% confidence, and the best fitting values of $\Omega_m$ in matter are $0.10^{+0.25}_{-0.10}$ and $-0.25^{+0.35}_{-0.25}$ assuming zero space curvature and zero cosmological constant, respectively. Note that identical results obtain when the low redshift bin, which includes Cygnus A, is excluded; these results are independent of whether the radio source Cygnus A is included. The method does not rely on a zero-redshift normalization. The radio properties of each source are also used to determine the density of the gas in the vicinity of the source, and the beam power of the source. The six new radio sources have physical characteristics similar to those found for the original 14 sources. The density of the gas around these radio sources is typical of gas in present day clusters of galaxies. The beam powers are typically about $10^{45} \hbox{erg s}^{-1}$.Comment: 39 pages includes 21 figures, accepted to Ap