Automated Spore Measurements Using Microscopy,Image Analysis,and Peak Recognition of Near-Monodisperse Aerosols

Rapid detection of airborne fungal and bacterial spores would enable public agencies to respond quickly and appropriately to intentional releases of hazardous aerosols. Automated analysis of microscope images and automated detection of near-monodisperse peaks in aerosol size distribution data offer complementary approaches to traditional methods for the identification and counting of fungal and bacterial spores. First, spores of the fungus Scopulariopsis brevicaulis were aerosolized in a chamber and then collected with a slit impactor; later, digital microscope images were analyzed manually to determine spore cluster distributions. The images also were analyzed with ImageJ, a program that automatically outlined objects and measured Feret's diameter, area, perimeter, and circularity. These characteristics were used to identify spore clusters automatically using two data analysis methods. Second, a computer program was developed to discriminate near-monodisperse bioaerosol peaks from those for polydisperse ambient particulate matter (PM) and was successfully tested using simulated and real aerosol mixtures. The observed agreement between manual and automated spore counts and the ability to detect spore peaks suggest that it may be possible to develop a system to recognize intentional releases rapidly through examination of particle morphology and size distributions. The peak detection procedure is potentially the fastest technique when used with real-time instrument data, but assumes that intentional releases would consist of large numbers of uniformly sized particles in the respirable size range.

Copyright 2012 American Association for Aerosol Research     

Passive Aerosol Sampler. Part I: Principle of Operation

A method has been developed to estimate average concentrations and size distributions with a miniature passive aerosol sampler. To use the passive sampler, one exposes it to an environment for a period of hours to weeks. The passive sampler is intended to monitor ambient, indoor, or occupational aerosols and has potential utility as a personal sampler. The sampler is inexpensive and easy to operate and is capable of taking long-term samples to investigate chronic exposures. After sampling, the passive sampler is covered and brought to the lab. Scanning electron microscopy (SEM) and automated image analysis are used to count and size collected particles with d_p     

Microwave modification of Radiata pine railway sleepers for preservative treatment

The use of hardwood railway sleepers in Australia is limited by hardwood timber resources, thus softwood sleepers made from plantation Radiata pine (Pinus radiata) may replace them. Low permeability pine heartwood does not allow for good impregnation with preservatives. Microwave (MW) wood modification increases heartwood permeability and improves preservative distribution and uptake. The experimental study of MW sleeper modification and impregnation, allows for the rational MW process parameters and preservative treatment schedules to be determined, with an estimate of the effect of MW treatment on sleeper quality, and for recommendations to be provided to industry. On the basis of the research results a 400 kW commercial MW plant capable of an output of 100,000 sleepers per annum has been designed. The costs of MW sleeper processing are acceptable to industry and provide good opportunities for the commercialization.     

A pilot study of the efficacy of residuum lodges for managing sediment delivery to impoundment reservoirs

Residuum lodges comprise small dams constructed on feeder streams immediately before they enter a reservoir, behind which ponds form, where sediment is deposited. Despite their construction on many impoundment reservoirs (IRE) and catchwaters, little research has previously investigated their efficacy at removing sediments from feeder streams. The current pilot study has, therefore, been carried out at an IRE supplying Halifax, West Yorkshire, UK, where a residuum lodge was recently cleaned out. Sediment concentrations reaching the reservoir were reduced by up to 42% although no certain impacts were noted on the other water quality variables that were measured. Moreover, it was found that the clearance operation did not result in the release of excessive quantities of sediment into the reservoir. It was estimated that the cleared residuum lodge would take 12 years to refill. A survey of other residuum lodges in the Yorkshire region showed there to be considerable differences in their remaining capacities.     

Terror management theory and self-esteem: Evidence that increased self-esteem reduced mortality salience effects.

On the basis of the terror management theory proposition that self-esteem provides protection against concerns about mortality, it was hypothesized that self-esteem would reduce the worldview defense produced by mortality salience (MS). The results of Exps 1 (49 undergraduates) and 2 (50 undergraduates) confirmed this hypothesis by showing that individuals with high self-esteem (manipulated in Exp 1; dispositional in Exp 2) did not respond to MS with increased worldview defense, whereas individuals with moderate self-esteem did. The results of Exp 3 (48 undergraduates) suggested that the effects of the 1st 2 experiments may have occurred because high self-esteem facilitates the suppression of death constructs following MS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Heroic Engineer

This paper is about the adjustment between real life and the growing knowledge of life. Real life refers here to the life of the good person and good citizen of a free society. The growing knowledge of life refers mainly to formal engineering education, but also to such informal mentoring as may be witnessed in engineering practice. What character traits in engineers compel them to care about others and enable them to live principled lives? How can engineering faculty help engineering students develop these traits? Our response to the first question relies on the scholarly viewpoint that immaturity in adults is a national problem for U.S. Americans. Our response to the second question relies on Joseph Campbell's antidote for immaturity in adults—the mythic hero's journey. Cases are studied wherein engineering teachers help engineering students achieve heroism: inwardly, by telling them stories of heroism in the practice of engineering; outwardly, by conditioning their learning experiences for heroism.