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The purpose of this study was to examine the impact of completing online diaries with specific topics on students’ self-regulated behavior in online courses. Also, this study sought to determine the impact of completing online diary topics with different topics (content-based or experience-based) on students’ self-regulation in online courses. The participants’ use of learning strategies was assessed to aid in this investigation. The research design utilized for this study was a quasi-experimental pretest/posttest design. The participants of this study included 30 undergraduate students from a variety of majors who were enrolled in one of two online courses. Of the 30 participants, 15 of the participants were in the content-based treatment group while the other 15 were in the experience-based treatment group. Convenience sampling was used to recruit participants for this study. Using data collected from the Motivated Strategies for Learning Questionnaire (MSLQ) and the diary entries submitted by the participants, the researcher did not find associations between completion of online diary topics and participants’ self-regulated behavior within the online courses. However, results did indicate that the content-based group reported higher levels of critical thinking usage than the experience-based group after the treatment was administered.

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In this dissertation fluorescence-based sensors for dissolved gases were developed for remote health monitoring applications including urine analysis. Detection of dissolved gases demonstrate diagnostic potential in body fluids, and indicate the metabolism of microorganisms driven by contaminated water. The emphasis of this research was on optimizing the sensitivity of fluorescence-based fluid sensing systems by configuring key design parameters towards cost reduction. A review of urine analysis indicated several methods for imaging, particle analysis, and detection of dissolved analytes. The review encourages readers to consider integrating sensing systems to provide additional context to results. An optical Dissolved Oxygen (DO) sensor was reproduced using phosphorescent organometallic dyes. The sensitivity of the DO sensor was experimentally optimized by employing Total Internal Reflection (TIR) of excitation light within the multilayered device by controlling the incident angle and sensitive film thickness. Novel 3D ray tracing-based computer models were developed based on the experimental results to explain the sensitivity enhancement mechanism of TIR. The path of light within the device and fluorescence generation sites were visualized and relative sensitivity was predicted. The model was validated by comparison with experimental results and expanded to predict the relative sensitivity of devices using different coupling strategies. This new optical model enables researchers to select an optimal coupling and detection scheme given their unique sensor design and application. A fluorescence based optofluidic sensor for Ammonia was redesigned based on experiment and simulation results. An optofluidic chip reader was produced to measure fluorescence sensors using low cost consumer electronics. The sensitivity of the ammonia sensor module has not been demonstrated; however, identified design challenges will be overcome in future efforts. As a result of this research, the cost of optofluidic sensing systems may be reduced towards enabling widely deployed remote monitoring networks for health and water quality. / Thesis / Doctor of Philosophy (PhD) / Dissolved gases have been detected in fluid samples as indicators of health and microbial activity by measuring changes in the intensity of fluorescence emitted from gas sensitive fluorescent dyes. These sensors can often be miniaturized and integrated to measure several parameters from a single platform. Several sensing platforms may be integrated into a continuous monitoring network. However, the cost of complete remote sensing networks prohibits the widespread deployment of these devices. The aim of this research was to improve the sensitivity of fluorescence-based sensors, reducing dependence on expensive detectors and light sources. The sensitivity of a fluorescence based dissolved oxygen sensor was optimized using Total Internal Reflection. A computer model was developed to identify important design parameters and their contributions to sensor performance. The model was validated by comparison with experimental measurements. Finally, an optical ammonia sensor is under development based on the dissolved oxygen experiments and model results.

Reflectivity images of the lower crust and uppermost mantle beneath the Illinois basin have been derived from reprocessing of several hundred kilometers of industry seismic reflection data using extended vibroseis recorrelation. The recorrelation was based on extending an originally 4-s correlated record, acquired with a 16-s sweep from 14 to 126 Hz, to the absolute limit of the full 20 s (~70 km) listening travel time. The reconstructed bandwidth includes frequency components suitable for imaging structures from signals received from both sedimentary basin reflectors and those received from reflectors in the deep crust and upper mantle. Mantle and sub-Moho reflectors are imaged down to 18 s two-way travel time (~62 km) and are observed on intersecting profiles generally dipping to the southwest and striking northwest-southeast. Occasional Moho reflections are also observed across the profiles (~12 s or ~38 km) while reflectivity in the lower crust is generally marked by intermittent horizontal packages and short, gently dipping reflections and diffraction segments. The presence of newly observed mantle reflectivity beneath the Illinois basin indicates significant upper mantle heterogeneity, relative to other parts of the USA studied using reflection methods. The relatively isolated occurrence of mantle reflections beneath the basin makes it difficult to uniquely infer their origin. However, available geologic and geophysical constraints, especially from geochemical and geochronological studies of drilled basement rocks, effectively limit the possibilities to: (1) remnants or "scars" of sub-crustal processes associated with lithospheric extension or delamination related to the melting of the Proterozoic crust that led to the emplacement of the granite--rhyolite province that underlies much of USA Midcontinent; or (2) deformation caused by plate subduction associated with the hypothetical accretion of a juvenile arc to the pre-1.6 Ga southern margin of the Laurentian continent.

Reflective practice is an integral component of a teacher's classroom success (Zeichner, 1996; Valli, 1997). Reflective practice requires a teacher to step back and consider the implications and effects of teaching practices. Research has shown that formal reflection on teaching can lead to improved understanding and practice of pedagogy, classroom management, and professionalism (Grossman, 2003). Several methods have been used over the years to stimulate reflective practice; many of these methods required teachers to use awkward and time-consuming tools with a minimal impact on teaching performance (Rodgers, 2002). This current study analyzes an innovative video-enhanced reflection process focused on improving teacher reflection. Video-enhanced reflection is a process that uses video analysis to stimulate reflective thought. The primary question of this study is "How does video analysis used in the context of an improved reflection technique impact teacher reflection-for-action?" The subjects of the study included five untenured teachers and one principal from an elementary school in a middle class residential area. A comparative case study approach was used to study the influence the video enhanced reflection model has on teacher reflection practices. The research method involved comparing typical teacher reflective practices with their experience using the video-enhanced reflective process. A series of vignettes and thematic analysis discussions were used to disaggregate, discuss, and present the data and findings. The findings from this study suggest the video-enhanced reflection process provides solutions to the barriers (i.e., time, tool, support) that have traditionally prevented reflection from being meaningful and long lasting. The qualitative analysis of teacher responses to the exit survey, interview findings, and comparison of the baseline and intervention methods suggests that the video-enhanced reflection process had a positive impact on teacher reflective abilities because it helped them more vividly describe, analyze, and critique their teaching.

Part of the curriculum in many composition classrooms contains a reflection component where students are required to think back over their writing and discuss strengths and weaknesses. Yet many of the reflections that students write fall short of the purpose of reflection when students fail to analyze their writing practices or to make future goals for themselves, a problem that occurs when higher level reflection strategies are not taught and practiced in the classroom. When students are taught to use reflection as a way to critically evaluate their writing, to make connections between class assignments and course objectives, and to make goals for future projects, reflection becomes a more useful tool for the composition student. In my study of two first-year composition classes, I compare the impact of instructing students about reflection and requiring them to practice good reflection against the more common practice of assigning reflection intermittently without formal instruction or feedback about what makes a constructive reflection. Through the results of my study, I confirm my hypothesis that when higher quality reflection is actively taught and promoted by the instructor, reflection helps students to integrate assignments into the course objectives, to extract personal significance from assignments, and to plan for future projects.

As video has become more accessible, there has been an increase in the use of video for teacher reflection. Although past studies have investigated the use of video for teacher reflection, there is not a review of practices and processes for effective use of video analysis. The first article in this dissertation reviews 52 studies where teachers used video to reflect on their teaching. Most studies included in the review reported that video was a beneficial feedback method for teachers. However, few studies discussed how video encourages teachers to change their practices. The second article in this dissertations investigates the how video influences the teacher change process. The study found that teachers did change their practices as a result of using video analysis. Teachers reported that video analysis encouraged them to change because they were able to: (a) focus their analysis, (b) see their teaching from a new perspective, (c) feel accountable to change their practice, (d) remember to implement changes, and (e) see their progress.