Far-side occupant kinematics in low speed lateral sled

OBJECTIVE: The objective of this study was to evaluate the far-side occupant kinematics in low-speed lateral pulses with and without a seatbelt system. METHODS: The kinematics responses of three volunteers and a Hybrid III were compared in three low-to-moderate lateral pulses. The parameters evaluated were pulses and belt usage. A total of 24 tests were carried out in a side-impact sled. The subjects consisted of two 50th-percentile males (Vol 1 & 2), one 5th-percentile female (Vol 3), and a Hybrid III 50th-percentile male (ATD). All subjects were seated in a far-side impact. Three low speed pulses were used: Pulse 1: a 4 g at 6 km/h, Pulse 2: 4 g/8 kph followed by a -2.5 g pulse to simulate a low curb impact, and Pulse 3: a 4 g's pulse at 10 km/h. In addition, the kinematics result from Pulse 2 was used to assess the performance of a human model. The human model was developed by TNO. RESULTS: For all three pulses, the peak head lateral displacement was greater with the 5th female (Vol 3) than the male volunteers. The ATD results in the 6 and 10 km/h pulses were comparable to the volunteers. However, in Pulse 2, the ATD motion was higher than the volunteers. CONCLUSION: The results obtained in this study suggest the Hybrid III is a somewhat conservative device for an evaluation of occupant kinematics in low-speed lateral pulses. The human model also seemed to be representative of volunteer kinematics.     

A comparison of volunteers and dummy upper torso kinematics with and without shoulder belt slack in a low speed side/pre-roll environment

OBJECTIVE: The objective of this study was to compare the occupant and dummy kinematics in a low-speed lateral environment with and without shoulder belt slack. METHODS: A buck of a small European car was mounted on a side impact sled. The parameters evaluated were pulses, sitting location, and belt slack. A total of 24 tests were carried out. Three 50th-percentile male volunteers and one Hybrid III 50th-percentile male were tested. The pulses consisted of Pulse 1:+/- 0.7 g's pulse and Pulse 2: a -0.9 g pulse to simulate low-speed pre-roll/side events. Both pulses had a duration of 500 msec. RESULTS: The peak lateral head excursion was higher in the far-side occupants than in the near-side occupants. Furthermore, for the far-side volunteers, lateral head displacements were lower in the no-slack condition than in the slack condition, at 388 +/- 64 mm and 455 +/- 84 mm respectively for Pulse 1 and at 138 +/- 2 mm and 207 +/- 70 mm for Pulse 2. The timing required to reach peak lateral displacement was higher in Pulse 1 than in Pulse 2. In comparison to the volunteers, the Hybrid III dummy lateral motion was lower. The peak lateral displacement in Pulse 1 was 231 mm with slack and 194 mm without and 98 mm and 107 mm for Pulse 2, respectively. CONCLUSIONS: The results obtained in this study indicate that removing seatbelt slack would be more beneficial for far-sided occupants than near-sided. They also point to the lack of biofidelity of the Hybrid III dummy in low g lateral pulses.     

Mixture toxicity of the antifouling compound irgarol to the marine phytoplankton species Dunaliella tertiolecta

This study examined the toxicity of irgarol, individually and in binary mixtures with three other pesticides (the fungicide chlorothalonil, and the herbicides atrazine and 2,4-D), to the marine phytoplankton species Dunaliella tertiolecta. Standard 96-h static algal bioassays were used to determine pesticide effects on population growth rate. Irgarol significantly inhibited D. tertiolecta growth rate at concentrations > or = 0.27 micro g/L. Irgarol was significantly more toxic to D. tertiolecta than the other pesticides tested (irgarol 96 h EC50 = 0.7 micro g/L; chlorothalonil 96 h EC50 = 64 micro g/L; atrazine 96 h EC50 = 69 micro g/L; 2,4-D 96 h EC50 = 45,000 micro g/L). Irgarol in mixture with chlorothalonil exhibited synergistic toxicity to D. tertiolecta, with the mixture being approximately 1.5 times more toxic than the individual compounds. Irgarol and atrazine, both triazine herbicides, were additive in mixture. The toxicity threshold of 2,4-D was much greater than typical environmental levels and would not be expected to influence irgarol toxicity. Based on these interactions, overlap of certain pesticide applications in the coastal zone may increase the toxicological risk to resident phytoplankton populations.     

Fatty acids mediate aggressive behavior in the spider Tegenaria atrica

Summary. The aggressiveness of the house spider (Tegenaria atrica) has a chemical basis in terms of intra- and interspecific chemical communication. Vibrations are used for longer range detection of intruders on the web territory whereas cuticular lipids mediate shorter range agonistic behaviors. Two cuticular acids were shown to promote aggressive responses from adult spiders, whereas mixtures of cuticular alkanes acted as inhibition signals.     

Environmental assessment of organic soybean (Glycine max.) imported from China to Denmark: a case study

Growing global trade with organic products has increased the demand for environmental impact assessments during both production and transport. Environmental hotspots of organic soybeans produced in China and imported to Denmark were identified in a case study using a life cycle assessment approach. Furthermore, environmental impacts of organic and conventional soybeans at farm gate were compared in the case study. The total global warming potential (GWP) per ton organic soybeans imported to Denmark revealed that 51% came from transportation and 35% from the farm level. Comparing organic and conventional soybean at farm gate showed that GWP, non-renewable energy use, acidification and eutrophication was lower per ton organic soybeans, whereas land use was slightly higher.