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441.
The context and habits of accident investigation practices were explored by means of questionnaire data obtained from accident investigators in the healthcare, transportation, nuclear and rescue sectors in Sweden. Issues explored included; resources, training, time spent in different phases of an investigation, methods and procedures, beliefs about causes to accidents, communication issues, etc. Examples of findings were: differences in the extent to which the ‘human factor’ was perceived as a dominant cause to accidents; manning resources to support investigations were perceived as rather scarce; underutilization of data from safety related processes such as risk analysis and auditing data; the phase of suggesting remedial actions (recommendations) were comparatively brief and generally not well supported. A majority of the investigators thought that the investigations were free from pressures to follow a specific direction; the investigators also thought that performing an investigation in itself (regardless of the specific results) had positive influences on safety. A majority of the investigators thought that upper management had a relatively strong influence on safety in the organizations. The results are discussed in terms of suggestions for strategies to strengthen investigation practices – particularly those conducted as part-time work in organizations.  相似文献   
442.
443.

Background

The Netherlands and Belgium have been among the first countries to offer non-invasive prenatal testing (NIPT) as a first-tier screening test. Despite similarities, differences exist in counseling modalities and test uptake. This study explored decision-making and perspectives of pregnant women who opted for NIPT in both countries.

Methods

A questionnaire study was performed among pregnant women in the Netherlands (NL) (n = 587) and Belgium (BE) (n = 444) opting for NIPT, including measures on informed choice, personal and societal perspectives on trisomy 21, 18 and 13 and pregnancy termination.

Results

Differences between Dutch and Belgian women were shown in the level of informed choice (NL: 83% vs. BE: 59%, p < 0.001), intention to terminate the pregnancy in case of confirmed trisomy 21 (NL: 51% vs. BE: 62%, p = 0.003) and trisomy 13/18 (NL: 80% vs. BE: 73%, p = 0.020). More Belgian women considered trisomy 21 a severe condition (NL: 64% vs. BE: 81%, p < 0.001). Belgian women more frequently indicated that they believed parents are judged for having a child with trisomy 21 (BE: 42% vs. NL: 16%, p < 0.001) and were less positive about quality of care and support for children with trisomy 21 (BE: 23% vs. NL: 62%, p < 0.001).

Conclusion

Differences in women's decision-making regarding NIPT and the conditions screened for may be influenced by counseling aspects and country-specific societal and cultural contexts.  相似文献   
444.
We have developed and applied a process-based model, the Wetland Ecosystem Model (WEM), to evaluate the effects of a prescribed fire on the phosphorus (P) dynamics and cattail (Typha domingensis) growth in a P-enriched area in the Florida Everglades. The WEM couples major ecosystem processes including carbon (C), nitrogen (N) and P biogeochemical cycles, plant growth, hydrology, and fire disturbance. The model is used to assess the effects of a prescribed fire on P dynamics and cattail growth through dynamic interaction among four modules: fire, water chemistry, soil, and vegetation. The simulation results are in agreement with observed data including cattail above- and belowground biomass and dead mass, P concentration in surface-water, pore-water, and soil, and soil and water temperature. Cattail aboveground biomass reached the unburned level one year after burn; belowground biomass recovered to unburned level one and half years after the fire, however, dead mass did not completely reach unburned level two years after fires. The fire increased water and soil temperatures in the short term, while indirectly increasing the sensitivity of water and soil temperature post-fire response to air temperature by altering the energy exchange between air and water through a canopy gap created by fire. The fire also altered the P dynamics in surface-water and pore-water. A post-fire P pulse that lasted for less than one month was observed in surface-water. A similar P pulse, but in a small magnitude and a longer duration, was also observed in the pore-water total phosphorus (TP), and then came back to normal level after approximately three months. No significant changes in soil TP was observed during the study period. Meanwhile, no significant changes in water nutrients were observed downstream of the study plot. This finding indicated that the P-enriched wetlands in Everglades act as a buffer in regulating the P concentration in surface-water. Our study showed that the distance of fire effects on a 300 m × 300 m plot was less than 300 m downstream. Sensitivity analysis identified that the air temperature and hydrological conditions are two important driving factors which may alter the cattail community dynamics in response to prescribed fires. Similar to the filed studies, this study provided evidences that fire played an important role in managing plant growth and P dynamics in the Florida Everglades.  相似文献   
445.
In birds as in many other taxa, parasites can have deleterious effects on offspring development. Therefore, avian mothers have evolved responses to counteract parasite virulence in offspring via transgenerational defense mechanisms that is the transfer of immune-enhancing substances such as antibodies to their eggs. Another maternal pathway is suggested by the finding that infested great tit mothers produced eggs with lower androgens, since these yolk androgens are immunosuppressive and potentially affect parasite susceptibility of the nestlings. However, whether this pathway is a specific adaptation to infestation with parasites that affect the offspring or an epiphenomenon of lower androgen production in the female due to the parasite effects on the mother itself is as yet unclear. In this study we infested female great tits (Parus major) with sheep ticks (Ixodes ricinus), which are nonnidicolous ectoparasites with low vertical transmission capability, and evaluated the effects on yolk androgen deposition. Tick-infested females did not significantly reduce their deposition of androgens (androstenedione (A4) and testosterone) compared to tick-reduced females, which is in contrast to a previous study showing a lowered deposition of A4 and testosterone when females were exposed to the nidicolous hen flea. Thus, females alter their hormone deposition, and thus likely offspring phenotype, when exposed to parasites that also form the parasitic environment of their offspring, but not when temporarily infested with the field-dwelling sheep ticks with low transmission capability. This suggests that selection favored the evolution of an adaptive transgenerational effect by acting mainly on the parasite-induced maternal effect.  相似文献   
446.
A model predicting 137Cs uptake in plants was applied on data from artificially contaminated lysimeters. The lysimeter data involve three different crops (beans, ryegrass and lettuce) grown on five different soils between 3 and 5 years after contamination and where soil solution composition was monitored. The mechanistic model predicts plant uptake of 137Cs from soil solution composition. Predicted K concentrations in the rhizosphere were up to 50-fold below that in the bulk soil solution whereas corresponding 137Cs concentration gradients were always less pronounced. Predictions of crop 137Cs content based on rhizosphere soil solution compositions were generally closer to observations than those based on bulk soil solution composition. The model explained 17% (beans) to 91% (lettuce) of the variation in 137Cs activity concentrations in the plants. The model failed to predict the 137Cs activity concentration in ryegrass where uptake of the 5-year-old 137Cs from 3 soils was about 40-fold larger than predicted. The model generally underpredicted crop 137Cs concentrations at soil solution K concentration below about 1.0 mM. It is concluded that 137Cs uptake can be predicted from the soil solution composition at adequate K nutrition but that significant uncertainties remain when soil solution K is below 1 mM.  相似文献   
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