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601.
Ambio - A horizon scan was conducted to identify emerging and intensifying issues for biodiversity conservation in South Africa over the next 5–10 years. South African biodiversity...  相似文献   
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Ambio - Ecosystem service assessments rarely consider flows between distant regions. Hence, telecoupling effects such as conservation burdens in distant ecosystems are ignored. We identified...  相似文献   
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Background

With more than a million youth living on agricultural operations, it is important for parents to understand the consequences of bystander injuries that children experience in these environments. We identified the childhood injuries for bystander status and compared the severity of these injuries to the working children in the Regional Rural Injury Study-II (RRIS-II).

Methods

RRIS-II followed 16,546 children (∼ 85% of eligible) from rural communities in the Midwest for two six-month recall periods in 1999 and 2001. Demographic, injury, and exposure data were collected through comprehensive computer-assisted telephone interviews. Child injuries were cataloged using narrative scenarios into four categories: (a) directly work-related; (b) indirectly work-related; (c) non-working accomplice; and (d) non-working attendant; the latter three all being bystander categories. Poisson regression modeling was used to calculate rates of bystander injuries. Frequencies were used for comparison of severity measures.

Results

Among the 463 child injuries (aged < 20 yrs), 102 were bystander injuries. Of the bystander-related injuries, 14 were identified as indirectly work-related (working bystanders), 27 as non-working accomplice (passengers/tag-alongs), and 60 as non-working attendant (playing on the operation). The overall rate of bystander injuries was 6.4 per 1,000 people, 95% CI (5.0, 8.1). Males, compared with females, had more than twice the injury rate (8.7; 95% CI 6.4-11.8, and 3.9; 95% CI 2.7-5.7, per 1,000 people, respectively). Bystanders in this population had more severe injuries with 4% having life-threatening circumstances; of these, 4% of the accomplices and 2% of the attendants subsequently died.

Conclusions

Children who live or work on agricultural operations are vulnerable to many hazards. Therefore, this study examined child injuries and found a clear difference in the consequences of these injuries between working-related and bystanding-related injuries.

Impact on Industry

Unlike occupations such as construction and mining, where laws and organizations have been created for the protection of bystanders, agricultural bystanders have remained unprotected and have had to face the consequent injury and death outcomes. As public health professionals considering these risks, it is necessary that we work to develop more intervention studies and continue to propose suggestive guidelines for child safety in these environments so as to challenge family traditions and possibly spark public policies that will give further protection to this population.  相似文献   
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Alexander D 《Disasters》1988,12(3):212-222
This report describes the progress of the landslide and flood emergency that occurred in Valtellina, in the northern Italian Alps, during July and August 1987. For the authorities, the critical problem was one of controlling the rise of a large lake impounded on the River Adda by landslide debris that threatened to breach catastrophically, releasing a major floodwave. Several lessons can be learned from the way in which the emergency was managed. First, helicopters played a critical role in evacuating survivors and moving supplies around the disaster area, but there was scope for better co-ordination of operations. Secondly, high levels of private car ownership allowed greater flexibility in designing mass evacutation plans for threatened communites, but such high personal mobility proved difficult to control in order to ensure public safety. In future, education programmes could be used to help people appreciate the dangers of driving during periods of great natural hazard risk. Thirdly, the Valtellina disaster coincided with a change of national government, including substitution of the Minister of Civil Protection. This led to a policy vacuum, sub-optimal decision making and erosion of public confidence in political leaders. Landslide-dammed lakes represent a widespread but rather unpredictable hazard: they therefore require flexible emergency repsonse, but not without decisive leadership.  相似文献   
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The dynamic behaviour of a model plankton community is described by solutions of a generalized predator‐prey model. The qualitative changes due to variations of parameters are considered and the existence of multistability and catastrophic behaviour is noted. Local and global bifurcations of the system are displayed. A seasonal variation of a parameter is introduced and the resulting dynamics are considered, such as quasiperiodic solutions or chaotic attractors.  相似文献   
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This work describes the development of an instrument for measuring free and total copper in seawater by continuous flow analysis (CFA) with an Orion copper (II) ion selective electrode (CuISE). Sample analysis times are reduced considerably by using an extrapolation technique based on the fitting of an empirical mathematical expression to the electrode time-response curve enabling a prediction of the final equilibrium potential. CuISE measurements in seawater samples containing nanomolar levels of total copper can be very time consuming, and this predictive approach significantly reduces sample analysis time, and improves sample throughput. The time taken to measure pCu in seawater to a precision of +/- 0.1, using conventional potentiometry, varies considerably depending on the condition of the electrode membrane but can be reduced by a factor of 3-6 (typically from 60 to 10 min) by using the extrapolation technique in conjunction with CFA. Details are given of the protocols used for preconditioning the CuISE. The system can be used as a portable instrument for field measurements or for shipboard measurements of free copper in seawater. Extrapolated equilibrium potentials are within +/- 0.5 mV of true steady state values.  相似文献   
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