Summary 0[ The individual and joint e}ectiveness of two biorational tactics "crop interference and exploitation of negative cross!resistance to certain herbicides# in the management of triazine!resistant Amaranthus hybridus L[ "smooth pigweed# were estimated[ Bio! rational tactics exploit biological idiosyncracies of resistant "R# genotypes to maximize _tness cost"s# of resistance[ We quanti_ed selection against triazine resistance by relative performance comparisons between lines having comparable nuclear genomes but either resistant or susceptible cytoplasm[ Increasing soybean density by reducing row spacing "from 65 cm to 14 cm# did not signi_cantly increase the _tness cost of resistance[ 1[ Low doses of bentazon "099 and 299 g active ingredient ha Ð0 # did strongly increase the cost of resistance[ Over 1 years\ the mean relative performance of R genotypes in bentazon treatments was 9=39\ compared to 9=59 in the absence of bentazon[ Therefore\ use of bentazon in soybean production has the potential to delay evolution of triazine resistance in maizeÐsoybean rotations using triazines[ 2[ There was no consistent indication that increased soybean density and bentazon herbicide could act synergistically to increase costs of triazine resistance in Amaranthus hybridus[ Nor were di}erences in response to biorational tactics evident between the two populations of origin "Maryland and Virginia\ USA# from which experimental lines were derived[ 3[ E}ects of the biorational tactics di}ered markedly between years\ highlighting that resistance management depending primarily on these tactics would have widely variable results[ Use of such tactics is likely to be most e}ective in the context of diversi_ed weed management[ Key!words] herbicide resistance\ negative cross!resistance\ resistance management\ Amaranthus hybridus\ weed evolution[ Journal of Applied Ecology "0888# 25\ 012Ð021

A series of experiments has been conducted to quantify the effects of laser wavelength and ambient luminance on the severity of laser eye dazzle experienced by human subjects. Eight laser wavelengths in the visible spectrum were used (458-647 nm) across a wide range of ambient luminance conditions (0.1-10,000  cd·m). Subjects were exposed to laser irradiance levels up to 600  μW·cm and were asked to recognize the orientation of optotypes at varying eccentricities up to 31.6 deg of visual angle from the laser axis. More than 40,000 data points were collected from 14 subjects (ages 23-64), and these were consolidated into a series of obscuration angles for comparison to a theoretical model of laser eye dazzle. Scaling functions were derived to allow the model to predict the effects of laser dazzle on vision more accurately by including the effects of ambient luminance and laser wavelength. The updated model provides an improved match to observed laser eye dazzle effects across the full range of conditions assessed. The resulting model will find use in a variety of laser safety applications, including the estimation of maximum dazzle exposure and nominal ocular dazzle distance values.

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We hypothesize that subject WK's interocular MPOD spatial distribution asymmetry resulted from his history of resolved CSC. This asymmetry is statistically significant at 2 degrees of retinal eccentricity and corresponds to the extent of retinal pigment epithelium changes observed on the fundus photographs. These findings suggest that MP and retinal pigment epithelium changes after a CSC episode are comparable in the area of the retina affected. These disruptions may also be measureable in other macular conditions in which the sensory retina is affected (e.g., cystoid macular edema and clinically significant macular edema).

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