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61.
Objectives: This study explored a theoretical model to assess the influence of culture on willingness and intention to drive under the influence of cannabis (DUIC). This model is expected to guide the design of strategies to change future DUIC behavior in road users.

Methods: This study used a survey methodology to obtain a nationally representative sample (n = 941) from the AmeriSpeak Panel. Survey items were designed to measure aspects of a proposed definition of traffic safety culture and a predictive model of its relationship to DUIC.

Results: Although the percentage of reported past DUIC behaviors was relatively low (8.5%), this behavior is still a significant public health issue—especially for younger drivers (18–29 years), who reported more DUIC than expected. Findings suggest that specific cultural components (attitudes, norms) reliably predict past DUIC behavior, general DUIC willingness, and future DUIC intention. Most DUIC behavior appears to be deliberate, related significantly to willingness and intention. Intention and willingness both appear to fully moderate the relationship between traffic safety culture and DUIC behavior.

Conclusions: This study explored a theoretical model to understand road user behavior involving drug (cannabis)-impaired driving as a significant risk factor for traffic safety. By understanding the cultural factors that increase DUIC behavior, we can create strategies to transform this culture and sustain safer road user behavior.  相似文献   

62.
The Floristic Quality Index (FQI) has been used as a tool for assessing the integrity of plant communities and for assessing restoration projects in many regions of the USA. Here, we develop a modified FQI (FQImod) for coastal Louisiana wetlands and verify it using 12 years of monitoring data from a coastal restoration project. Plant species that occur in coastal Louisiana were assigned a coefficient of conservatism (CC) score by a local group with expertise in Louisiana coastal vegetation. Species percent cover and both native and non-native species were included in the FQImod which was scaled from 0–100. The FQImod scores from the long-term monitoring project demonstrated the utility of this index for assessing wetland condition over time, including its sensitivity to a hurricane. Ultimately, the FQI developed for coastal Louisiana will be used in conjunction with other wetland indices (e.g., hydrology and soils) to assess wetland condition coastwide and these indices will aid managers in coastal restoration and management decisions.  相似文献   
63.

Problem

This study examined novice drivers’ overconfidence by comparing their self-assessed driver competence with the assessments made by driving examiners.

Method

A Finnish (n = 2,739) and a Dutch sample (n = 239) of drivers license candidates assessed their driver competence in six areas and took the driving test.

Result and Discussion

In contrast to previous studies where drivers have assessed their skill in comparison to the average driver, a smaller proportion overestimated and a larger proportion made realistic self-assessments of their driver competence in the present study, where self-assessments were compared with examiner assessments. Between 40% and 50% of the candidates in both samples made realistic assessments and 30% to 40% overestimated their competence. The proportion of overestimation was greater in the Dutch than in the Finnish sample, which might be explained by greater possibilities for practicing self-assessment in the Finnish driver education system. Similar to other self-assessment studies that indicate that incompetence is related to overestimation, a larger proportion of candidates that failed the test overestimated their skill compared to those who passed. In contrast to other studies, males did not overestimate their skills more than females, and younger driver candidates were not more overconfident than older drivers.

Impact on traffic safety

Although a great proportion of the candidates made a realistic assessment of their own driver competence, overestimation is still a problem that needs to be dealt with. To improve the accuracy of novice drivers’ self-assessment, methods for self-assessment training should be developed and implemented in the driver licensing process.  相似文献   
64.
In the future, the Baltic Sea ecosystem will be impacted both by climate change and by riverine and atmospheric nutrient inputs. Multi-model ensemble simulations comprising one IPCC scenario (A1B), two global climate models, two regional climate models, and three Baltic Sea ecosystem models were performed to elucidate the combined effect of climate change and changes in nutrient inputs. This study focuses on the occurrence of extreme events in the projected future climate. Results suggest that the number of days favoring cyanobacteria blooms could increase, anoxic events may become more frequent and last longer, and salinity may tend to decrease. Nutrient load reductions following the Baltic Sea Action Plan can reduce the deterioration of oxygen conditions.  相似文献   
65.
Presence of low-weight carboxylic acids (LWCAs) can be the reason for phytotoxicity of green manures, treated bio-waste or digestates from biogas production applied to soils. As the phytotoxic concentrations of LWCA are poorly known, this work presents data on six acids (C(1)C(6): formic, acetic, propionic, butyric, valeric, and caproic). Phytotoxicity was measured in acute (72 or 120 h) and subchronic (21 d) assays for seed germination, seedling elongation, and plant growth for garden cress Lepidium sativum and ryegrass Lolium multiflorum. The dose-response relationship was modeled using Weibull model. Results showed a trend that toxicity of LWCA increases with the length of the carbon chain, formic acid (C(1)) being the least and caproic acid (C(6)) the most toxic. EC50 values in the acute seed germination of cress ranged between 1.9 and 4.2mM and for ryegrass between 1.8 and 6.4mM. In subchronic assays EC50 values for germination were in a range from 11 to 46mMkg(-1)dm for cress, and from 18 to 127 mM kg(-1) dm for ryegrass. EC50 values for early seedling growth of cress based on acute assays ranged from 0.7 to 2.3mM and that of ryegrass from 1.2 to 1.8mM. Range of EC50 values for shoot biomass of cress was between 8 and 40 mM kg(-1) dm and of ryegrass between 12 and 93 mM kg(-1) dm.  相似文献   
66.
Climate change is likely to have large effects on the Baltic Sea ecosystem. Simulations indicate 2–4 °C warming and 50–80 % decrease in ice cover by 2100. Precipitation may increase ~30 % in the north, causing increased land runoff of allochthonous organic matter (AOM) and organic pollutants and decreased salinity. Coupled physical–biogeochemical models indicate that, in the south, bottom-water anoxia may spread, reducing cod recruitment and increasing sediment phosphorus release, thus promoting cyanobacterial blooms. In the north, heterotrophic bacteria will be favored by AOM, while phytoplankton production may be reduced. Extra trophic levels in the food web may increase energy losses and consequently reduce fish production. Future management of the Baltic Sea must consider the effects of climate change on the ecosystem dynamics and functions, as well as the effects of anthropogenic nutrient and pollutant load. Monitoring should have a holistic approach, encompassing both autotrophic (phytoplankton) and heterotrophic (e.g., bacterial) processes.  相似文献   
67.
The need to develop biological effects monitoring to facilitate a reliable assessment of hazardous substances has been emphasized in the Baltic Sea Action Plan of the Helsinki Commission. An integrated chemical–biological approach is vitally important for the understanding and proper assessment of anthropogenic pressures and their effects on the Baltic Sea. Such an approach is also necessary for prudent management aiming at safeguarding the sustainable use of ecosystem goods and Services. The BEAST project (Biological Effects of Anthropogenic Chemical Stress: Tools for the Assessment of Ecosystem Health) set out to address this topic within the BONUS Programme. BEAST generated a large amount of quality-assured data on several biological effects parameters (biomarkers) in various marine species in different sub-regions of the Baltic Sea. New indicators (biological response measurement methods) and management tools (integrated indices) with regard to the integrated monitoring approach were suggested.  相似文献   
68.
Objective: We examined both fatal and injury at-fault crashes of a population of passenger cars fitted with electronic stability control (ESC). Crash rates were calculated in relation to both registration years and mileage. Crash rates were also calculated for a non-ESC car population and crash rate ratios were calculated to compare the crash risk between ESC-fitted and non-ESC-fitted passenger cars.

Methods: Passenger car models with and without ESC were identified (ESC-equipped cars: 3,352,813 registration years; non-ESC-equipped: 5,839,946 registration years) and their vehicle information for the period 2009–2013, including mileage (ESC-equipped vehicles: 89.3 billion kilometers; non-ESC-equipped: 72.4 billion kilometers), was drawn from the national Vehicular and Driver Data Register.

The registry of Finnish road accident investigation teams was accessed and all fatal at-fault crashes among the cars in the study populations (ESC 97; non-ESC 377) for the period 2009–2013 were analyzed. The motor insurance database includes at-fault crashes leading to injuries and was utilized for analyses (ESC: N?=?8,827, non-ESC: N?=?21,437).

Crash rates and crash rate ratios were calculated to evaluate crash risk of both ESC-equipped and non-ESC-equipped passenger cars. Poisson regression was used to model crash involvement rate ratios both per registration year and per mileage for vehicles with ESC and without ESC, controlling for age and gender of the vehicle owner and vehicle mass.

Results: Passenger cars fitted with ESC showed lower crash rates than non-ESC-equipped cars in all crash types studied. In general, the difference in crash rates between ESC-equipped and non-ESC-equipped vehicles was greater when the crashes were compared to the mileage rather than registration years. The mileage-proportional crash rate of ESC-equipped cars was 64% (95% confidence interval, 61%; 67%) lower in run-off-road crashes resulting in injury and as much as 82% (65%; 91%) lower in fatal run-off-road crashes when suicides and disease attacks were not taken into account.

Conclusions: Our results show that modern passenger cars provide a significant crash risk reduction, which depends on both ESC and passive safety features introduced. Results also show that exposure evaluation in terms of registration years (or vehicle population) instead of true mileage can provide an overly pessimistic view of the crash risk.  相似文献   
69.
70.
Comprehensive two dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-TOF-MS) was used for screening and semiquantitation of semivolatile organic compounds in aerosol particles. As the volatility was a prerequisite parameter for the analysis, some compounds were transformed via derivatization such as silylation into more volatile ones. The identification of the analytes was made by comparing the GC retention indices and the TOF mass spectra with the NIST and the Golm metabolome database reference libraries. The data treatment was simplified by exploiting an additional classification of the identified compounds, namely the main functional group or specific element present in the molecule leading to different groups of compounds. This methodology was applied to identify compounds in 30 ± 4 nm, 50 ± 5 nm and total suspended particles (TSP) collected during spring and autumn of 2009 and summer of 2010 at the Station for Measuring Forest Ecosystem Atmosphere Relations (SMEAR II) at Hyyti?l? (Finland). The number of identified compounds was higher than 400, which were the most relevant compounds present in the samples, in terms of concentrations. The analysis of aerosol particles of different sizes, collected simultaneously, revealed that the number of compounds increased with the particle size whereas the normalized response factor decreased in most of the cases, aldehydes being an exception. This decrease could be associated with the formation or aggregation of new compounds onto the particles when they grow in the atmosphere.  相似文献   
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