2012 MU theses - Freely available online
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Item Analysis of the information needs of primary care physicians in an electronic health record (EHR)(University of Missouri--Columbia, 2012) Clarke, Martina A.; Kim, Min S.BACKGROUND: With the increase in the adoption of electronic health records (EHR) across the US, clinicians are experiencing information overload. In order to address the problem of information overload, an assessment of the information needs of clinicians will assist in understanding what the clinicians view as useful information to make patient care more efficient. AIM: The purpose of this study is to understand the information display needs of primary care physicians in an electronic health record (EHR). METHOD: A systematic review of studies was conducted with a comprehensive search in PubMed, CINAHL, SCOPUS, references from relevant papers and hand-searched articles were examined to identify articles applicable to this review. An interdisciplinary team conceptualized nine interview questions over weekly group sessions and fictitious but typical acute and chronic physician's documentation (progress notes) was created by two family medicine physicians (JLB and RJK). An analysis of hour long semi-structured interviews was conducted with a sample size of 15 primary care physicians from the University Missouri health clinics in Columbia, MO. Participants were instructed to think aloud while identifying by highlighting with markers the key pieces of information in the note that are most relevant to their information needs during guided review of the progress notes Data analysis was conducted with the assistance of NVivo by coding transcripts and progress notes in order to run queries. RESULTS: Of the papers reviewed, the most common information needs found among clinicians were related to diagnoses, drug(s), and treatment/therapy. Colleagues remain a preferred information source among clinicians; however, a rise in Internet usage is apparent. Results from the study, shows that History of Present Illness, Assessment and Plan were the more frequently identified sections of a progress note by primary care physicians across all three scenarios and Review of Systems was frequently identified as a section in the note that is generally more than needed. Physicians view the Review of Systems as a billing requirement and not a useful part of a progress note for patient care. For Past Medical History, Temperature and Chest were highlighted as important in an acute visit because of the nature of the visit being for a cough while Problems, Smoking Habits, and Medications were highlighted more frequently on a chronic disease note possibly because of the nature of the visit being a follow up for diabetes and other problems. Although Allergies and Medications are closely related, Allergies was not identified as an important part of Past Medical History. Results show that physicians highlighted less information when it was their note and their patient than when they were viewing their partner's note and seeing their partner's patient. CONCLUSIONS: These results from this study can assist electronic health record vendors on how best to create progress notes for physicians to use effectively. Future plans for this project includes: coding interview transcripts, expanding research for transferability by integrating results from other user groups (patients and auditors), presenting the developed prototypes to stakeholders through focus groups and apply usability inspection methods to evaluate user interaction with newly designed prototype, and expanding the scope of the work to include specialists, nurses, pediatrics and all different patient types.Item Evaluation of temporary ramp metering for work zone safety(University of Missouri--Columbia, 2012) Zhu, Zhongyuan; Edara, Praveen K. (Praveen Kumar)Ramp metering has been successfully implemented in many states and studies have documented its positive mobility and safety benefits. However, there have been no studies on the use of ramp metering for work zones. This thesis reports the results from the first deployment of temporary ramp meters in work zones in the United States. Temporary ramp meters were deployed at seven work zones in Missouri. Due to lack of crash data, this study uses video data to extract alternative safety measures such as driver compliance, merging behavior, speed differentials, lane changing, and braking maneuvers. This evaluation suggests that temporary ramp meters should only be deployed at work zone locations where there is potential for congestion and turned on only during periods of high congestion. In comparison to over 90% compliance rates of permanent ramp meters implemented in other states, field data showed compliance rates from 40.5% to 82.9% in temporary ramp meter. This suggested that non-compliance could be a major safety issue in the deployment of temporary ramp meters. The use of a three-section instead of a traditional two-section signal head used for ramp metering produced significantly higher compliance rates. This thesis then aggregated the data into groups to further analyze the effects of different factors such as platoons, commercial trucks, work zone type and work zone-ramp configuration. After analyzing general characteristics of mainline and ramp vehicle speed and speed differentials, this study then focused on findings for different comparison groups. The two comparison groups are "between two work zones" versus "before work zone" configuration and "left-lane closed" versus "right-lane closed" work zone type. Results indicated lower mean speeds of mainline and ramp vehicles and higher differentials when ramp metering was turned on. This is expected and again temporary ramp meters are recommended only where congestion occurs. Congestion will lead to lower mainline speeds thus lower speed differentials either with or without ramp metering. Finally, analysis of merging headways showed that temporary ramp meters were effective in separating platoons before vehicles merged into mainline. This produces more single-vehicle merging which requires shorter gaps and causes fewer impacts on the mainline traffic.Item Characterization of a soybean BAG gene and its potential role in nematode resistance(University of Missouri--Columbia, 2012) Yeckel, Gregory Joseph; Mitchum, Melissa G.Plants resistant to the soybean cyst nematode (SCN) mount a hypersensitive cell death-like response upon nematode feeding, but the genes regulating this process are not known. Laser-assisted microdissection of nematode feeding cells coupled with microarray analysis identified a soybean gene upregulated 87-fold in plants resistant to SCN that shared sequence similarity with the Arabidopsis BAG6 (Bcl-2 associated athanogene 6) gene. BAG genes encode an evolutionarily conserved family of proteins in animals, yeast and plants. These proteins contain a conserved BAG domain which mediates interaction with the molecular chaperone HSP70/HSC70. Members of the BAG protein family in animals and yeast function in apoptosis to regulate a range of activities from inhibition to promotion of cell death. However, much less is known about the role of BAG proteins in plants. A family of seven BAG genes (AtBAG1-7) has been identified in Arabidopsis. AtBAG6 was shown to induce programmed cell death in both yeast and Arabidopsis. Expression of a truncated version of the protein, spanning a calmodulin-binding IQ domain and the BAG domain, enhanced the cell death phenotype. Here, we demonstrate that similar to AtBAG6, overexpression of the full length GmBAG6A protein or a truncated version spanning the IQ and BAG domains, induced cell death in yeast and plants, with the truncated form showing an enhanced cell death phenotype. Expression of the truncated form in Arabidopsis and soybean under the control of a nematode-inducible promoter significantly reduced nematode development demonstrating its potential use in engineering a novel form of nematode resistance in crop plants.Item Control of Bermudagrass (Cynodon dactylon) in Zoysiagrass (Zoysia japonica) turf by using post-emergence herbicides(University of Missouri--Columbia, 2012) Song, Enzhan; Xiong, XiBermudagrass and zoysiagrass are two commonly used turfgrass on golf course fairways in the southern and transition zone of the United States. Due to its excellent turf performance and superior cold tolerance compared to bermudagrass, zoysiagrass are the dominant turfgrass used in upper transition zone area, including Missouri. However, bermudagrass still brings encroachment problem on many zoysiagrass fairways. Similar sensitivities of the two species to most commonly used herbicides make it difficult to remove one from the other. Experiments were first conducted in the greenhouse with different herbicides and plant growth regulators applied to 'Quickstand' and 'Riviera' bermudagrass, and 'El Toro' and 'Meyer' zoysiagrass. The most promising chemicals that produced highest discoloration to bermudagrass but minimum impact on zoysiagrass were tested on a golf course where severe bermudagrass encroachment happened on the zoysiagrass fairway. The results show that aryloxyphenoxypropionate (AOPP) herbicides fenoxaprop or fluazifop combined with triclopyr at 0.14 + 0.23 kg ha-1 or 0.09 + 1.0 kg ha-1 provided 100% bermudagrass control without compromising desired turfgrass quality. However, the greenhouse study showed that 'Quickstand' and 'Riviera' bermudagrass exhibited different sensitivities to AOPP herbicides, leading to 2[about]7 folds discoloration differences. Although they are in the same species, genetic variations still exist and most likely contribute to the differentiated responses. This study suggested that both inter- and intra-species variations need to be considered before developing a turfgrass herbicide program to control bermudagrass encroachment into zoysiagrass. Future studies focused on investigation of the mechanisms underline the intra-species differentiation among bermudagrass varieties are still on-going.Item Wireless signal acquisition and processing techniques for horse lameness detection and evaluation(University of Missouri--Columbia, 2012) Nguyen, Bao Anh; Pai, P. Frank (Perngjin Frank)The Equine Lameness Locator(R) (ELL) is a newly developed system that provides a robust and objective method to detect and evaluate equine lameness. To achieve objective lameness evaluation, the system analyzes a horse's head and pelvis vertical movement signals during trotting. Two uniaxial accelerometers are placed on the horse's torso, one each on the horse's head and pelvis to record vertical accelerations. Vertical position signals are obtained by numerical double integration of the acceleration signals. However, these integrated position signals contain very large moving averages and require advance methods of signal processing for correction. In this thesis, a combination of the Hilbert Huang transform and a conjugate-pair decomposition method is proposed and tested against the current ELL's signal processing method, a sliding-window curve-fitting method. Numerical simulations and experimental results show that the proposed new method involves more intense computation but does not provide better results for lameness evaluation of horses. Hence, the original sliding-window curve-fitting method is recommended for future use. Clinical and experimental observations reveal that a horse's head and pelvis also rotate during trotting. These rotations may cause inaccurate measurements of the true vertical accelerations. Hence, this work also numerically and experimentally examines the influences of rotations on the measured vertical accelerations. Numerical techniques, unique experimental devices and setups, and an algorithm for correcting accelerometer outputs to obtain true vertical accelerations have been developed and experimentally validated.