Common milkweed (Asclepias syriaca L.) response to sulcotrione

A laboratory bioassay was conducted to investigate common milkweed response to sulcotrione. Sulcotrione was applied in concentration series of 0.15-0.90 kg a.i./ha without a surfactant and with Dash? at 1 L/ha. Plants grew for 14 days, upon which period morphological (height and fresh weight) and physiological parameters (content of carotenoids, chlorophyll a and chlorophyll b) were measured. Visual crop injury was estimated 7 and 14 days after treatment. Sulcotrione caused leaf bleaching and reduction in pigments content in common milkweed leaves and the degree of change depended on application rates and whether it was applied with or without the surfactant. Inhibition was slightly higher in plants which were treated with a combination of herbicide and surfactant. Based on the findings in this study, common milkweed showed moderate susceptibility to the recommended field rates of sulcotrione.

Interaction of Particles with the Pulmonary Interface: Effects on Surface Elasticity

We present an experimental study of the interactions of negative and positive model particles and their influence on the surface elasticity of biomimetic pulmonary surfactant. In this purpose we have measured the adhesion force between negative (G) and positive (GS) particles and supported lipid bilayer by Atomic Force Spectroscopy. In addition, the modification in surface elasticity of lipid monolayer under quasistatic compression when interacting with negative and positive particles was investigated on a Langmuir trough. We found that, positive particles interact poorly with biomimetic pulmonary surfactant, therefore no modifications in surface elasticity were observed. Conversely, negative charged particles interact strongly with the biomimetic pulmonary surfactant, decreasing the surface elasticity. The results are directly relevant for understanding the interactions and the effects of particulate matter on pulmonary structures which could lead to pulmonary surfactant inhibition or deficiency causing severe respiratory distress or pathologies.