Figure 1: Normalized specific four-day growth () dose-response curve. Solid circles are Al2O3 (17.6 nm). Open squares are SiO2 (14.3 nm). Solid triangles are TiO2 (18.7 nm). Error bars are ±1 standard deviation (). Lines represent four-parameter logistic curves fitted to the data in SigmaPlot ver. 9.01. Experimental conditions: initial algae concentration = cell/mL, test duration = 4 days, and initial test volume = 200 mL.