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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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Peer mentoring programs are an important component in the strategy to enhance the first year undergraduate experience. The
operation of these programs needs to be informed by evidence as to their effectiveness. In this article we report on a six-year
study of the development of a peer mentoring program in which feedback is used to improve program implementation. Evidence
from surveys of participants in the program shows that this process has significantly enhanced their experiences and that
the effects of these benefits have increased throughout the life of the program. Moreover, participation in the program enhanced
the leadership, communication, and organizational skills of the peer mentors. 相似文献
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For decades, the HIV epidemic has exacted an enormous toll worldwide. However, trend analyses have discerned significant declines in the overall prevalence of HIV over the last two decades. More recently, advances in biomedical, behavioural, and structural interventions offer considerable promise in the battle against generalised epidemics. Despite advances in the prevention of transmission and new infections, morbidity and mortality of HIV among young people remains a considerable concern for individuals, couples, families, communities, practitioners, and policy-makers around the globe. To accelerate the end of the global HIV epidemic among young people, we must merge existing efficacious interventions with more novel, cost-effective implementation strategies to develop integrated, multi-level combination interventions. The benefits of conceptualising the HIV epidemic more broadly and adopting ecological frameworks for the development of HIV prevention programmes are critical. 相似文献
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How environmental knowledge measures up at a Big Ten university 总被引:1,自引:1,他引:0
The reported research examines the level of environmental knowledge of Michigan State University students relative to the results of a biannual national study of the environmental knowledge of the general population of the United States. While the university students were found to possess higher levels of environmental knowledge than the general public, the students' overall environmental knowledge, on average, was deficient with only 66% of them receiving a passing grade. The findings suggest a positive correlation between academic level, field of study and environmental knowledge. 相似文献
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