Benzene (C 6H6) is the simplest member of the aromatic hydrocarbon group of chemical compounds. Minute amounts of benzene are naturally released into the environment during volcanic eruptions and forest fires. This extremely stable aromatic compound is also an important industrial chemical and is an integral component of many petroleum products. In fact, benzene is amongst the top 20 in production volume for chemicals produced in the United States. Therefore, it is not surprising that the major reason for environmental contamination through benzene is by anthropogenic sources. Benzene is relatively soluble in water and migrates very quickly in the soil after its entry. The Environmental Protection Agency (EPA) has classified benzene as a Class A carcinogen. Microorganisms play an integral role in the natural attenuation of benzene from the environment. Biodegradation of benzene by oxidation can occur under aerobic, anaerobic and microaerophilic conditions. Biooxidation of benzene under aerobic conditions is well-studied. However, oxygen is scarce in contaminated subsurface environments, and after the aerobic breakdown of benzene, oxygen is quickly depleted from the most heavily contaminated regions leading to the development of extensive anaerobic zones. As a result, there is increased focus on anaerobic benzene degradation as a potential bioremediation technique in anoxic subsurface environments. In aerobic and microaerophilic environments, monooxygenase and dioxygenase enzyme systems have been established to be involved in the breakdown of the benzene ring. However, the genes and enzymes involved in anaerobic benzene oxidation pathway are still unknown. In the present study, Dechloromonas aromatica strain RCB, capable of benzene oxidation with nitrate as the electron acceptor, was used as a model system to investigate the initial steps of the anaerobic benzene oxidation pathway. Strain RCB is capable of completely mineralizing benzene to carbon dioxide in denitrifying conditions. RNA-arbitrarily primed polymerase chain reaction (RAP-PCR), a differential gene expression technique used to randomly reverse-transcribe RNA into cDNA, was conducted to identify genes exclusively expressed during nitrate-dependent benzene oxidation. A total of seven genes were identified as differentially expressed in the presence of benzene using the RAP-PCR approach. Four differentially expressed genes were confirmed by a second method, semiquantitative reverse transcriptase PCR (RT-PCR). Microarray analysis was the second expression analysis technique conducted to identify genes expressed during benzene-oxidizing conditions. Based on fold induction and potential function, six genes were selected from the microarray data and their differential expression was confirmed by using semiquantitative RT-PCR. Interestingly, Daro1556, encoding a hypothetical protein, was identified by both RAP-PCR and microarray analysis. In order to verify the functions of the genes (selected from RAP-PCR and microarray analysis) in nitrate-dependent benzene oxidation, six deletion mutants were constructed in which the target gene was replaced by a tetracycline cassette. The correct insertion of the tetracycline cassette in the mutant genome was confirmed by PCR and Southern blotting. Microarray results were further analyzed by using an unsupervised clustering approach, k-means. A couple of genes (Daro1358 and Daro1359) obtained from cluster analysis were also verified by semiquantitative RT-PCR. These two genes, part of the same operon, encode a two-component monooxygenase system, which is a member of the Rieske non-heme iron aromatic ring-hydroxylating oxygenase family of proteins. In the present investigation, for the first time, involvement of a monooxygenase system (Daro1358 and Daro1359) during benzene oxidation with nitrate reduction was observed. Based on the results obtained from k-means cluster analysis, a model was hypothesized for anaerobic benzene oxidation with nitrate as the electron acceptor in Dechloromonas aromatica strain RCB.

The purpose of this research was to revise the Male Rape Myths Scale (MRMS; Kerr Melanson, 1999) and gather psychometric information using the gender role strain paradigm (GRSP; Pleck, 1991, 1995) as a theoretical framework in samples of U.S. undergraduate students. I provided evidence for a 16-item revised version of the MRMS (MRMS-R) across three studies. The MRMS items were first revised based on the results of a pilot study and expert reviews. Exploratory factor analyses revealed a correlated two-factor model: (1) Marginalization and Homophobia and (2) Victim Blame and Denial of Trauma. Results of the confirmatory factor analyses provided support for bifactor and correlated two-factor models of the MRMS-R. Criterion validity was supported based on (a) differences in MRMS-R scores between men and women and (b) lower scores for participants who reported experiencing a sexual assault. MRMS-R scores were also correlated with victim blaming responses to case vignettes and female rape myth acceptance in the expected directions. Construct validity was further demonstrated by correlations between MRMS-R scores and measures of traditional gender role attitudes, homonegativity toward gay men, and patriarchal beliefs. Further, the bifactor model met criteria for measurement invariance between male and female groups. The total and subscale scores had high internal consistency estimates of reliability. Results provided preliminary support for the use of the MRMS-R as an updated measure of male rape myth agreement among college student populations, and clarified links to other gender-related constructs. Limitations, implications, and recommendations for future research are also discussed.

Energy dissipation during penetration is an important consideration in materials selection for lightweight armoring to protect against hypervelocity impacts (HVIs). Impact-induced glass transition in polymeric materials has been observed to increase energy dissipation during penetration. Incorporating unconventional armor materials like polymers could improve performance in these types of applications. A series of HVIs was performed, with impact velocities over the range of 2-7 km/s, on samples of ultra-high molecular weight polyethylene and poly(methyl methacrylate). A relationship between back face debris cloud velocity and impact velocity was developed for each material. Damage zone sizes were compared, offering insights into the effects of molecular architecture on stress delocalization and energy dissipation during hypervelocity perforation. Thermal analysis of the two material systems provides quasi-static glass transition temperatures, as well as melting and crystallization temperatures. The apparent failure mechanisms, in conjunction with thermal analysis, were used to explain the relative performance of each material.

Effects of gender and strain cross on carcass characteristics, meat quality and sensory acceptability were studied. Strains consisted of a commercially available strain (Strain A), and a strain genetically selected to maximize breast yield currently in the test phase (Strain B). Broilers varying in gender and strain cross had similar compositional characteristics; all treatments yielded high quality breast and thigh meat and did not differ in sensory acceptability. Effect of salt concentrations on yields, instrumental quality, and sensory acceptability of broiler breast meat was determined. Breast fillets were vacuum-tumbled with different concentrations (0, 0.25, 0.50, 0.75, 1.00, 1.25 and 1.50%) of NaCl and 0.35% sodium tripolyphosphate (STP). Marination showed improvent in CIE L*, shear force, and cooking loss. Marinated samples were highly acceptable to the majority of consumers. Results indicate that 0.5-1.0 % NaCl could be used to effectively marinate broiler breast meat depending on product application and desired attributes.

A need exists for a more robust method of evaluating musculoskeletal injuries resulting from impact conditions, particularly blasts. Computational modeling is a promising method of achieving this goal. The accuracy of a model depends on high quality mechanical properties for each component. This study examined the mechanical properties of porcine muscle along with structure property relationships. Fresh muscle was tested in compression and tension at strain rates of 0.1 s-1, 0.01 s-1, and 0.001 s-1. Viscoelastic properties were observed including strain rate dependency, stress state dependency, anisotropy, relaxation, and hysteresis. Image analysis was conducted in compression on controls, 30% strain, and 50% strain, relating stress-strain data with structural changes. The effect of rigor was also seen in the tensile response of muscle. Thawed tissue was examined to investigate the effects of freezing. It was found that freezing did not significantly change the mechanical properties, but substantial microstructural changes did occur.

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The development and example applications of a new EBSD-based texture analysis system are presented. This new system uses the cross-correlation function to compare two EBSD patterns at a number of corresponding regions in each pattern to calculate the deformation gradient tensor. Bragg's Law-based simulated EBSD patterns are used as reference patterns in the cross-correlation method to enable the measurements of absolute elastic strain and lattice orientation at discrete points in a crystalline sample. The resolution limits of this new method are explored using a variety of computational and physical experiments. The simulated pattern method is estimated to be able to measure lattice orientations to within +/-0.02° and elastic strains to within +/-3.6x10-4 for small strains and +/-1x10-3 for large strains. Two example applications are demonstrated. The first demonstration is estimating the dislocation density in a 5.5% compressed Mg-based AZ91 alloy. Nye's and Kröner's formulations are used to estimate the dislocation density. Comparisons are made with traditional OIM measurements and it is found that the simulated pattern method offers an order of magnitude improvement in dislocation density estimations over OIM. The second demonstration is tetragonality measurements of HSLA 65 steel along the weld line of a friction stir welded plate. Accurate tetragonality measurements in the bainite phase of the steel can be made using information from the diagonal components of the elastic strain tensor. The measured tetragonality can be related to the concentration of interstitial carbon atoms in the iron lattice to find the carbon distribution in the sample. From these experiments, it is demonstrated that the simulated pattern method presents a new and powerful methodology for texture analysis that exhibits both ease of use and access to high resolution orientation and elastic strain data.

Conductive nanocomposites are finding many uses as multi-functional materials. One recent development involves the creation of high displacement strain gauges, which have potential applications in a variety of engineering roles. The piezoresistive nature of the gauges makes possible their strain sensing capability. The intent of this research is to show that specific High Displacement Strain Gauges can successfully be used in one human-machine interface application that will demonstrate their potential for a range of other human-machine interface applications. This will be shown in the development of these sensors to accomplish hand pose determination. The flexible and inexpensive gauges are attached to several locations on a glove. It is then shown that by linking this glove with software, the position of the hand can be interpreted into the letters of the American Sign Language alphabet. This use of this nanocomposite sensor establishes the potential for future applications. Issues such as accuracy of response, cyclability, recalibration and reliability are discussed. A design of experiments is accomplished in order to evaluate the effects of modification of the gauges in order to overcome these issues. This work develops the potential of these sensors for use in human-machine interface applications such as computer games, remote controls, robotics, prosthetics and virtual reality applications.