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Peanut skins have long been a waste product of the peanut industry. The aim of this project was to find suitable applications for this rich source of natural bioactive compounds. Solvent extracts of peanut skins and a multistep solvent extraction process to yield oligiomeric procyanidin (OPC) extracts were found to be inhibitory towards three types of yeasts (Saccharomyces cerevisiae, Zygosaccharomyces bailli, and Zygosaccharomyces bisporus). All extracts were devoid of solvents that may have interfered with the results. The OPC extract exhibited the highest inhibitory effect, and was chosen for fractionation. Fractionation was conducted by means of a silica or size exclusion high performance liquid chromatography (HPLC) column. Fractions were then subjected to a yeast growth curve assay to determine the active fractions. The fractions were then characterized by liquid chromatography-mass spectrometry (LC-MS). Negative mode electrospray MS determined the fractions to contain mostly procyanidins but also proanthocyanidins. Since it is possible for multiple compounds to display the same molecular ion, multistep MS and retention time differences were utilized to tentatively identify the compounds based upon their fragmentation schemes. However, co-elution was prominent, thus specific compounds responsible for yeast growth inhibition could not be determined. The yeast inhibition assay demonstrated that the procyanidin dimers up to tetramers had the best anti-yeast capabilities.

Multi-wavelength laser exposures pose unique safety challenges for both laser experts and users of laser systems. This study uses mathematical programming techniques to optimize optical density (OD) requirements for multi-wavelength laser exposures. Formulated as a mixed-integer nonlinear programming model, overall light transmittance is maximized while maintaining eye-safe viewing conditions during a multi-wavelength exposure, thus minimizing the total OD required for sufficient laser eye protection (LEP). To optimize transmittance, Spectral Luminous Efficiency data is utilized (allowing transmittance increases in the visible wavelengths) along with transmittance data from specific LEP technologies to provide users with optimally designed eye-safe LEP for multi-wavelength lasers

A statistical screening design was used to test 12 emulsion and processing variables said to influence covering power in silver halide emulsions. Emulsion grain size was found to be the only statistically significant factor at an alpha risk of .10.

During the course of growth in a bacterial culture, cellular development and reproduction take place in a regular and orderly manner. It is possible to observe definite phases in the normal growth of a culture. Some method of evaluation of the growth must be used in order to determine the population change or the effect of chemical and physical environment on bacterial cells. Numerous methods have been tried, employing the total population number or rate of production is used in this investigation as an indication of population growth of Escherichia coli, Proteus morgani and Shigella sonnei. There has been infrequent mention in the literature of the employment of acid production as a measure of the growth rate of a bacterial culture. Porter (1946) and Wilson and Miles (1946) state that little data regarding the use of acid production is available, while Mond (1949) mentions that acid production may be used as an indication of growth. Application of this method of measuring growth is limited. Since scant study on acid production has been done, this investigation was undertaken as an attempt to determine what, if any, correlation exists between acid production from a fermentable sugar and growth rate.