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Off-plane x-ray reflection gratings are theoretically capable of achieving high resolution and high diffraction efficiencies over the soft x-ray bandpass, making them an ideal technology to implement on upcoming x-ray spectroscopy missions. To achieve high effective area, these gratings must be aligned into grating modules. X-ray testing was performed on an aligned grating module to assess the current optical alignment methods. Results indicate that the grating module achieved the desired alignment for an upcoming x-ray spectroscopy suborbital rocket payload with modest effective area and resolving power. These tests have also outlined a pathway towards achieving the stricter alignment tolerances of future x-ray spectrometer payloads, which require improvements in alignment metrology, grating fabrication, and testing techniques.

Marine to freshwater colonizations constitute among the most dramatic evolutionary transitions in the history of life. This study examined evolution of ionic regulation following saline-to-freshwater transitions in an invasive species. In recent years, the copepod Eurytemora affinis has invaded freshwater habitats multiple times independently. We found parallel evolutionary shifts in ion-motive enzyme activity (V-type H(+) ATPase, Na(+) /K(+) -ATPase) across independent invasions and in replicate laboratory selection experiments. Freshwater populations exhibited increased V-type H(+) ATPase activity in fresh water (0 PSU) and declines at higher salinity (15 PSU) relative to saline populations. This shift represented marked evolutionary increases in plasticity. In contrast, freshwater populations displayed reduced Na(+) /K(+) -ATPase activity across all salinities. Most notably, modifying salinity alone during laboratory selection experiments recapitulated the evolutionary shifts in V-type H(+) ATPase activity observed in nature. Maternal and embryonic acclimation could not account for the observed shifts in enzyme activity. V-type H(+) ATPase function has been hypothesized to be critical for freshwater and terrestrial adaptations, but evolution of this enzyme function had not been previously demonstrated in the context of habitat transitions. Moreover, the speed of these evolutionary shifts was remarkable, within a few generations in the laboratory and a few decades in the wild., (© 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.)

Worker exposures to metalworking fluids were characterized at a plant that produced air compressors. Full-shift, side-by-side air samples (n = 147) were collected and analyzed for total particulate matter, extractable total particulate matter, thoracic particulate matter, and extractable thoracic particulate matter. The thoracic particulate matter geometric mean of 0.32 m/m (3)was below the National Institute for Occupational Safety and Health (NIOSH) recommended exposure limit (REL) of 0.4 mg/m (3). The total particulate matter geometric mean of 0.52 mg/m (3), however, was above 0.5 mg/m (3), the total particulate matter concentration offered as a surrogate REL in the NIOSHCriteria for a Recommended Standard for Occupational Exposure to Metalworking Fluids.[1]Of the 83 total particulate matter results that were at or above smash 0.5 mg/m (3), only 50 (60%) of the corresponding thoracic particulate matter results were at or above 0.4 mg/m (3). These data indicated a conversion factor of 1.65 between thoracic particulate matter and total particulate matter concentrations and 1.40 between thoracic extractable particulate matter and total extractable concentrations. These factors were significantly different from the 1.25 used to compare total particulate matter with thoracic particulate matter concentrations in the NIOSHCriteria Document[1](p < 0.01) and call into question the validity of a universal conversion factor. The authors conclude that thoracic particulate matter exposure assessment should be done directly. In terms of protecting the worker, however, the 1.25 conversion factor appeared to be conservative since each time a total particulate matter result was below 0.5 mg/m (3), its paired thoracic particulate matter measurement was below 0.4 mg/m (3).