Effects of thiobencarb on growth, photosynthesis and photoinhibition of Nostoc sphaeroides colonies were examined. Thiobencarb concentrations higher than 2 mg/l led to a significant decrease in phycoerythrin, phycocyanin and allophycocyanin content, but no significant effect on chlorophyll a (chl a) content. Biomass yield, protein content and photosynthetic rate were reduced only in the highest thiobencarb concentration (10 mg/l). Colonies exposed to high thiobencarb dose (10 mg/l) were more sensitive to high light than those exposed to the control and 4 mg/l thiobencarb. Dim light induced recovery from photoinhibition to more great extent in colonies grown in the control and 4 mg/l thiobencarb than 10 mg/l thiobencarb. Darkness resulted in a insignificant recovery regardless of thiobencarb treatments. 相似文献
Objectives: This article aims to model fault in e-bike fatal crashes in a county-level city in China.
Method: Three-year crash data are retrieved from the crash reports (2012–2014) from the Taixing Police Department. A mixed logit model is introduced to explore significant factors associated with fault assignment, as well as accounting for similarity among fault assignment and heterogeneity within unobserved variables.
Results: The modeling results indicate some interesting new findings. First, precrash behaviors of both drivers and e-bike riders are found to be significant to fault assignment. Second, bike lane and median type are significantly associated with e-bike rider fault commitment. Third, specific groups of e-bike riders (low-educated and older) and drivers (heavy good vehicles) are more likely to be at fault in e-bike crashes. Last, crash location and the built environment have significant correlations with faulty behaviors of e-bike riders.
Conclusions: Safety countermeasures are proposed including (1) the deployment of traffic design and control elements including physically separated bike lanes, medians, video surveillance systems for e-bike riders, and left-turning treatments for nonmotorists (e.g., a 2-step e-bike left turning); (2) the amendment of the current traffic regulations on drunk e-bike riders and child e-bike passengers; (3) the development of a license system for specific e-bike rider groups (older and low-educated) and a safety campaign for drivers (to increase safety awareness when parking on-street or driving heavy good vehicles). Some interesting future research topics are also suggested: e-bike riders' behaviors at unsignalized intersections and mid-block openings, e-bike safety in suburban areas, and an in-depth study of the effect of the built environment on e-bike safety. 相似文献