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Christopher J. McNamara Margaret Breuker Marie Helms Thomas D. Perry Ralph Mitchell 《Journal of Cultural Heritage》2004,5(4):361-364
Outdoor bronze sculptures are highly susceptible to corrosion in many environments and organic coatings are widely used for their protection. The purpose of this study was to determine the susceptibility of the commonly used coating Incralac to biodeterioration by microorganisms. A yeast was isolated from a bronze statue treated with Incralac and its ability to degrade Incralac was determined using growth curves, scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS). The organism grew slowly on Incralac in liquid culture, but SEM images demonstrated its ability to adhere to Incralac coated metal. Additionally, the yeast caused a rapid drop in the low frequency impedance of Incralac coated metal that was not observed under sterile conditions, indicating that the organism accelerated deterioration of the coating. The potential for microbial growth to accelerate deterioration of Incralac should be considered when developing a maintenance strategy for the protection of outdoor metal monuments. 相似文献
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A new set of standards to guide professional development in assessment among student affairs professionals and faculty members is poised to revolutionize how educators learn to conduct this essential work. 相似文献
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Eagan MK Sharkness J Hurtado S Mosqueda CM Chang MJ 《Research in higher education》2011,52(2):151-177
Despite the many benefits of involving undergraduates in research and the growing number of undergraduate research programs,
few scholars have investigated the factors that affect faculty members’ decisions to involve undergraduates in their research
projects. We investigated the individual factors and institutional contexts that predict faculty members’ likelihood of engaging
undergraduates in their research project(s). Using data from the Higher Education Research Institute’s 2007–2008 Faculty Survey,
we employ hierarchical generalized linear modeling to analyze data from 4,832 science, technology, engineering, and mathematics
(STEM) faculty across 194 institutions to examine how organizational citizenship behavior theory and social exchange theory
relate to mentoring students in research. Key findings show that faculty who work in the life sciences and those who receive
government funding for their research are more likely to involve undergraduates in their research project(s). In addition,
faculty at liberal arts or historically Black colleges are significantly more likely to involve undergraduate students in
research. Implications for advancing undergraduate research opportunities are discussed. 相似文献