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Expert Interview with Dr. Thomas Parham (Chapter from Love, Intimacy, and the African American Couple)
No full texthttps://digitalcommons.lewisu.edu/psychology_fac-books/1021/thumbnail.jp
Threats to Intimacy for African American Couples (Chapter from Love, Intimacy, and the African American Couple)
No full texthttps://digitalcommons.lewisu.edu/psychology_fac-books/1015/thumbnail.jp
Bioavailable Lead in Topsoil Collected from General Aviation Airports
Get PDFRepresentatives of the aviation community are interested in determining the environmental effects of leaded fuel emissions from general aviation flight operations. Soil is an environmental sink for lead to accumulate over time. This study measured bioavailable lead concentrations in topsoil at three general aviation airports and at one site with no general aviation operations in order to determine if general aviation aircraft operations are contributing to the contamination of airport topsoil at levels that require remediation by law. Bioavailable refers to substances that organisms can absorb, because they have access to them. Topsoil was collected from refueling areas, run-up areas, and approach corridor/departure end runways. The samples were dried and the fine fractions were separated. The fine fractions were suspended in nitric acid to extract the lead for laboratory analysis. A univariate ANOVA was computed comparing the quantity of soluble lead in the topsoil from three general aviation airports(further classified as high, moderate, and low volume of flight operations) and at one site with no general aviation operations (arboretum). A significant main effect for the high volume airport was found (F[2, 24]= 10.966,p\u3c .05), in which the lead in topsoil samples from high volume airports were lower than the samples from the other airports, but similar to the arboretum. Another analysis was calculated comparing quantity of soluble lead in topsoil at sites within airports (refueling areas, run-up areas, and approach corridor/departure end runways). No significant main effect was found among the sites (F[4, 24]= 1.065, p\u3e .05). However, an interaction was observed when comparisons were made between the airport sites (n= 3) and locations sampled at the sites (n= 3) that was significant (F[4, 24]= 2.902,p\u3c .05). Tukey’s HSD was used to determine the nature of the differences. The analysis revealed that concentrations of lead in soil samples collected from the high volume airport refueling area, run-up area, and approach corridor/departure end runway were significantly lower than the moderate volume airport run-up area lead concentrations. The results at the three airports investigated support the conclusions that the risk of ingesting lead from surface soils is low and bioavailable lead in the soil sampled from general aviation airports is not accumulating in quantities that require remediation according to Environmental Protection Agency requirements
Conclusion (Chapter from Love, Intimacy, and the African American Couple)
No full texthttps://digitalcommons.lewisu.edu/psychology_fac-books/1017/thumbnail.jp
Couples Interviews (Chapter from Love, Intimacy, and the African American Couple)
No full texthttps://digitalcommons.lewisu.edu/psychology_fac-books/1022/thumbnail.jp
Lead Memory in General Aviation Aircraft Engine Emissions
Get PDFThere is interest from environmental organizations and regulating agencies to eliminate lead and reduce pollutants emitted into the atmosphere from general aviation aircraft using 100LL aviation gasoline (Avgas). 100SF (Swift Fuel) is under development by Swift Enterprises as a lead free general aviation alternative fuel product. The purpose of this study is to determine the amount of time required for engines to be free of lead emissions when first introduced to operation using 100SF. This study also investigated the lead cleansing decay profiles of the aircraft engines under 100SF initial operations. Results of this study revealed that a mean engine run time of 21minutes and 20 seconds was needed before aircraft engines were free of measurable lead at a 15ppm limit of detection. Results lend support for 100SF as a lead free alternative fuel source that also acts as a lead cleanser for general aviation aircraft engines
Evaluation of the catalytic decomposition of H2O2through use of organo-metallic complexes - A potential link to the luminol presumptive blood test
No full textForensic scientists use several presumptive tests to detect latent blood stains at crime scenes; one of the most recognizable being the luminol reagent. Luminol, under basic conditions, reacts with an oxidizing species which, with the help of a transition metal catalyst facilitates a luminescent response. The typical oxidizing species used in the luminol reaction is hydrogen peroxide (H2O2). While the luminol reaction has been studied since its inception, the mechanistic pathway is still an area of great debate. Previous work suggests that the luminol reaction with latent blood stains possesses a correlation to the Fenton-Decomposition reaction mechanism, which decomposes H2O2 into the strongly oxidizing hydroxyl radical (*OH) species. This work seeks to understand the luminol reaction on a mechanistic level and to determine if a synergy exists between the chemiluminescence observed in the reaction and the production of the hydroxyl radical via Fenton-like processes. Results indicate that organo-metallic complexes produce hydroxyl radicals at different rates and different concentrations. These findings appear to be related to structural differences in the organo-metallic complex, which conform to the 18 electron rule or are one electron rich/deficient. Furthermore, the production of *OH is controlled by the chemical environment which governs complex stability at high pH conditions, reflective of the luminol process. Model hemoglobin systems reveal a strong correlation between the rate of *OH production via the Fenton-like pathway and maximum chemiluminescent intensity
A Useful Roadmap Through the World of Algae, Protozoa, and Fungi
Get PDFReview of: Eukaryotic Microbes; Moselio Schaechter; (2012). Academic Press, San Diego, CA. 479 pages
The Relationship Between African American Enculturation and Racial Identity
No full textAbstract
This study investigated how predictive the Cross Racial Identity Scale (CRIS; B. J. Vandiver, W. E. Cross, F. C.Worrell, & P. Fhagen-Smith, 2002), a measure of Black racial identity, was of African American cultural practices, beliefs, and attitudes (i.e., enculturation) as measured by the African American Acculturation Scale-33 (H. Landrine & E. Klonoff, 1995). Findings revealed that all but 1 of the CRIS subscales significantly predicted enculturation. Theoretical and practical implications are discussed
