http://hdl.handle.net/10724/3 2017-06-29T04:08:21Z 2017-06-29T04:08:21Z Carr, Brendan M. http://hdl.handle.net/10724/36944 2017-03-31T04:32:00Z 2016-12-01T00:00:00Z

Screening for recidivism Carr, Brendan M. The purpose of this study was to determine predictive capabilities of The Reynolds Intellectual Screening Test (RIST; Reynolds and Kamphaus, 2003) and age at time of psychological evaluation in determining whether juveniles will reoffend in 24-months. The RIST is comprised of two subtests of The Reynolds Intellectual Assessment Scales (RIAS; Reynolds and Kamphaus, 2003) assessment and can be used as a screening tool for intellectual impairment. Data from 202 youth offenders were included in the current study after being court-referred for psychological evaluation. Test of discriminant function was conducted. These findings suggest that the RIST, in combination with age, may show promise as an efficient screener for youth at lower risk of recidivism. Limitations and directions for further research are discussed.

2016-12-01T00:00:00Z Campbell, Mary Allison http://hdl.handle.net/10724/36943 2017-03-31T04:31:59Z 2016-12-01T00:00:00Z

Improvement of southern stem canker screening methods and characterization of Georgian Diaporthe aspalathi isolates Campbell, Mary Allison Southern soybean stem canker caused by Diaporthe aspalathi has caused major soybean losses for growers in the Southeast U.S. The most effective disease management tool for growers is the use of stem canker resistant soybean varieties. A fast, reliable greenhouse assay for stem canker would help ensure elite germplasm is resistant to this disease. An existing toothpick assay was modified to include culturing D. aspalathi on oxgall agar on toothpicks pre-soaked in oxgall liquid medium. Inoculation was performed at growth stage V2 between cotyledons and the first trifoliate, inoculation sites were sealed with petroleum jelly and seedlings were incubated in humidity chambers for 72 h. Stem canker disease was highly consistent on susceptible lines and was not observed on resistant germplasm. More than 99.0% disease incidence was observed across three isolates of D. aspalathi after 4 weeks. This improved greenhouse assay will assist in future breeding efforts for stem canker.

2016-12-01T00:00:00Z Burke, Dallas Cory http://hdl.handle.net/10724/36942 2017-03-31T04:31:58Z 2016-12-01T00:00:00Z

A phenomenological study of the symbiotic nature of teaching and composing that exists within the contemporary band educator/conductor/composer Burke, Dallas Cory Although the contemporary band director functions on a time-intensive schedule, a small population of these educators spend much of their non-teaching time composing music for ensembles they direct. This study sought to probe the mindset, motivation, and philosophical underpinnings of the band educator-composer. To understand the symbiotic relationship between the role of composer and educator, a population of 20 published band educator-composers was surveyed, using both Likert-scale and open-ended responses. The research findings identified band composer-educators as predominantly middle-aged white males with a master’s degree. While practical based reasons for their additional careers as composers were cited, such as helping support family or earning money towards retirement, their greatest motivation was identified as the joy garnered from their personal artistic expression. Perhaps a less expected finding, the majority of this population did not begin their careers with the intent to compose. More often, their interest in composition began by writing band arrangements; expanding to original works when they saw a need for literature suitable for their ensembles. Those who have followed this path generally write for the educational market (grade levels 1-4) and see no dichotomy of quality between “educational” and “artistic” works. Rather they consider their compositions as a balance between artistic expression and the practical demands (and limitations) of younger, developing musicians.

2016-12-01T00:00:00Z Bullock, Hannah Alissa http://hdl.handle.net/10724/36941 2017-03-31T04:31:57Z 2016-12-01T00:00:00Z

Methylmercaptopropionate-CoA ligase and methylthioacryloyl-CoA hydratase from the dimethylsulfoniopropionate demethylation pathway Bullock, Hannah Alissa The organosulfur compound dimethylsulfoniopropionate (DMSP) is a valuable commodity for both the phytoplankton that produce it and the marine bacteria that degrade it. While phytoplankton use DMSP primarily as an osmolyte, for marine bacteria DMSP is also a source of reduced carbon and sulfur. The enzymes involved in the pathways for bacterial DMSP metabolism, the cleavage and demethylation pathways, were identified in the roseobacter Ruegeria pomeroyi DSS-3. These advances have allowed for in-depth studies of the pathways’ enzymes, their regulation, and diversity. Characterization of the DmdB methylmercaptopropionate (MMPA)-CoA ligase isozymes, RPO_DmdB1 and RPO_DmdB2, from R. pomeroyi revealed these enzymes have activity with a range of substrates but have adapted specific regulatory features for catalyzing reactions with the demethylation pathway intermediate MMPA. The DmdB isozymes were differentially regulated with RPO_DmdB1 being stimulated by increasing ADP levels while RPO_DmdB2 responded to increasing MMPA. DmdB may also be regulated by acetylation. RPO_DmdB2 showed reduced activity when acetylated with a protein N-acetyltransferase. Multiple deacetylases from R. pomeroyi could reverse the acetylation. The methylthioacryloyl (MTA)-CoA hydratase DmdD catalyzes the final reaction of the demethylation pathway, but is not widely distributed phylogenetically. An alternative enzyme, AcuH, was identified in R. pomeroyi and Ruegeria lacuscaerulensis. AcuH was present in diverse microorganisms and exhibited activity towards MTA-CoA and the cleavage pathway intermediate acryloyl-CoA. The regulation of the demethylation and cleavage pathways is still under investigation. While ADP influenced the activity of both DmdB and AcuH, the availability of free tetrahydrofolate (THF) and turnover of methyl-THF may also play a regulatory role. The first step of the demethylation pathway utilizes THF and produces methyl-THF. When THF availability was limited, dimethyl sulfide (DMS) production increased indicating elevated use of the cleavage pathway. Additionally, the specific activities of enzymes required for the turnover of methyl-THF were two-fold higher in cell extracts grown on DMSP compared with acetate. Based on the current evidence, the DMSP degradation enzymes have likely been recruited from preexisting metabolic pathways. While DmdB and AcuH clearly function in DMSP metabolism, they have broader substrate specificities allowing them to carrying out a range of reactions for other pathways.

2016-12-01T00:00:00Z