The flea beetle Altica litigata (Chrysomelidae) is an insect herbivore to plants within the families Lythraceae and Onagraceae, including ornamentals such
as crape myrtle, Lagerstroemia spp. This insect is important both as a pest species and as a naturally occurring biological control agent due to its aggregate
feeding behavior, which typically results in severe defoliation of the host plant. Despite the negative economic impact to
ornamentals and contrary benefits as a biological control agent, there are few reports on the semiochemical communication
of this family of insects. Uruguayan primrose-willow (Ludwigia hexapetala) is an invasive aquatic weed in California and serves as a host to A. litigata. To better characterize this association, the volatile emissions of A. litigata were collected while the flea beetles were: in containers by themselves, in containers with L. hexapetala leaves, in situ on L. hexapetala leaves in a growth chamber, and in situ on L. hexapetala leaves in the field. For comparison, the volatile emissions of A. litigata associated with two subspecies of creeping water primrose (L. peploides) were also evaluated. Two himachalene-type sesquiterpenes, showing the same carbon skeleton as compounds previously reported
from Aphthona flava and Epitrix fuscula, were detected as volatiles from A. litigata. 相似文献
The release of packaged or containerized dangerous goods during transport can have serious consequences on board a ship. This study was focused on identifying factors contributing to these types of releases and on investigating the contribution of dangerous goods accidents to overall container ship accident rates. Records of dangerous goods releases from a US and a UK database for an 11-year period covering 1998–2008 were analyzed to identify and categorize main contributing factors. The majority of releases, estimated as 97% of the US events and 94% of the UK events, did not follow another primary accident type such as a collision. Faults that occurred during activities such as preparation of the goods for transport, packaging, stuffing containers, and loading the ship were main factors contributing to the release of the dangerous goods on board the ship. For container ship casualties occurring worldwide during the same period, 1998–2008, accidents involving packaged dangerous goods were estimated to account for 15% of all fatalities. Self-ignition or ignition of incorrectly declared dangerous goods was identified as a contributing factor for the fatal accidents. Ensuring that dangerous goods are correctly prepared and documented for marine transport is thus very important for preventing releases and improving on board safety. 相似文献
Incineration is one of the key technologies in disposal of municipal waste, which produces municipal solid waste incineration (MSWI) residues with high valuable metal contents. The recycling strategy for the MSWI residues is typically focused on the recovery of scrap metals yielding processed municipal solid waste incineration residues (PIR) as the main byproduct. However, the PIR still contains valuable metals, particularly gold, which cannot be extracted by conventional methods. Here, we evaluated the feasibility of using the 0.5–2.0 mm grain size fraction of PIR containing 28.82 ± 1.62 mg/kg of gold as raw material for a two-stage extraction process. In the first stage the alkalic fine-grained PIR was acidified with a solution of 20% (v/v) of HCl-containing flue gas cleaning liquid that is obtained by the municipal waste incineration plant itself as a waste product. In the second stage we leached the acidified fine-grained PIR by thiourea with Fe3+ as an oxidant. Application of the thiourea-Fe3+ leaching system resulted in recovery of 16.4 ± 1.56 mg/kg of gold from the fine-grained PIR within 6 h of incubation. Due to high gold market prices, upscaling of the suggested technology can represent a suitable strategy for gold recovery from PIR and other MSWI residues.
OBJECTIVES: To determine factors affecting the severity of motorcycle injuries, considering variables related to the individual, the environment, the vehicle, and the crash. METHODS: This is a register-based retrospective cohort study. All individuals born in 1970-1972 (n = 334,070) were extracted from the Swedish Population and Housing Census of 1985 and followed up from 1988 to 2000, when aged 16-30. All subjects whose records indicated an injury as a motorcycle driver in the Swedish National Road Administration Accident Database were selected, and constituted the study population (n = 1,748). Factors related to the individual, the environment, the vehicle, and the crash were considered as exposure measures, whereas the outcome measure was the level of injury severity, based on assessments made on-site by police officers, in two categories: fatal/severe and minor. Associations between individual, environmental, vehicle and crash factors and injury severity were measured, using Chi-square, and through univariate and multivariate stepwise logistic regression. RESULTS: Factors such as alcohol consumption, traffic environment, speed limit, and type of crash were significantly associated (p < 0.0001) with injury severity. More specifically, a positive suspicion of alcohol consumption, driving in a rural area, and a posted speed limit over 50 km/hour were all factors positively associated (OR > 1.0) with the likelihood of being severely injured. On modeling all the variables together through stepwise logistic regression, positive suspicion of alcohol emerged as the strongest determinant (adjusted OR = 2.7) of a severe outcome. CONCLUSIONS. Motorcycle crashes still place a heavy burden on young drivers. Increased efforts are needed to prevent alcohol-related crashes-through law enforcement and a multiplicity of policies at local and national levels. 相似文献