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91.
Reed MA Naftel RP Carter S MacLennan PA McGwin G Rue LW 《Traffic injury prevention》2006,7(3):256-263
OBJECTIVE: Motor vehicle collision (MVC)-related spinal injury is a severe and often permanently disabling injury. In addition, strain injuries have been reported as a common outcome of MVCs. Although advances in automobile crashworthiness have reduced both fatalities and severe injuries, the impact of varying occupant restraint systems (seatbelts and airbags) on thoracolumbar spine injuries is unknown. This study examined the relationship between the occurrence of mild to severe cervical and thoracolumbar spine injury and occupant restraint systems among front seat occupants involved in frontal MVCs. METHODS: A retrospective cohort study was conducted among subjects obtained from the 1995-2004 National Automotive Sampling System. Cases were identified based on having sustained a spine injury of >/=1 on the Abbreviated Injury Scale (AIS), 1990 Revision. Risk risks (RRs) and 95% confidence intervals (CIs) were computed comparing occupant restraint systems with unrestrained occupants. RESULTS: We found an overall incidence of AIS1 cervical (11.8%) and thoracolumbar (3.7%) spinal injury. Seatbelt only restraints were associated with increased cervical AIS1 injury (RR = 1.40, 95% CI 1.04-1.88). However, seatbelt only restraints showed the greatest risk reduction for AIS2 spinal injuries. Airbag only restraints reduced thoracolumbar AIS1 injuries (RR = 0.29, 95% CI 0.08-1.04). Seatbelt combined with airbag use was protective for cervical AIS3+ injury overall (RR = 0.29, 95% CI 0.14-0.58), cervical neurological injury (RR = 0.19, 95% CI 0.05-0.81), and thoracolumbar AIS3+ injury overall (RR = 0.20, 95% CI 0.05-0.70). CONCLUSIONS: The results of this study suggest that seatbelts alone or in combination with an airbag increased the incidence of AIS1 spinal injuries, but provide protection against more severe injury to all regions of the spine. Airbag deployment without seatbelt use did not show increased protection relative to unrestrained occupants. 相似文献
92.
Gerald Fischer Tina Frohne Lydia Gerharz Margit Hildebrandt Otto Klemm Katrin Mildenberger Carsten Nording Ingo Rehberger Manuel Schiffer Christos Stephan Voulkoudis 《Environmental Sciences Europe》2006,18(3):155-163
Objective and Background
The nitrogen oxides NO and NO2 and, in particular, their ratio (NO/NO2), play important roles in the radical-system of the atmospheric boundary layer. There were various indications upon a dropping NO/NO2-ratio in citiex over the last years, however, no proof has been given yet Especially in densely populated areas such as the federal state of North Rhine-Westphalia (NRW), such a change can have significant influences upon various atmospheric reactions. The objective of this investigation was to prove the existence of a systematic change of the NO/NO2-ratio, to describe the development of NOx over the past 2 decades at different locations and to determine the causes for this development.Methods
To detect changes of the NO/NO2-ratio we processed the data of 11 continuously operating air quality stations of the State Environment Agency (LUA NRW) with time series reaching back up to 20 years. We investigated rural stations, stations in the urban background and heavily traffic influenced locations. It was possible to calculate and assess the NO/NO2-ratio under consideration of the fast reaction of ozone with NO. There were clear indications towards existing trends and they could be determined as statistically significant using the nonparametric Mann-Kendall Test. The analysis of possible causes for the change of the NO/NO2-ratio focused upon the change of the global radiation, the change of the patterns of the atmosphetic circulation, and the frequency of cyclones and anticyclones meteorological conditions in Central Europe, the introduction of automotive catalytic converters, and the development of the atmospheric oxidation-capacity.Results and conclusions
The results are indicating a decline of the ratio at traffic-influenced stations with a statistical significance over 95%. The negative trend can also be detected at most urban background stations. It was problematic to perform the trend-analysis of the rural background station in the Egge-Mountains because of the fragmentary character of the dataset. Regional differences in the development of the NO/NO2-ratio indicate towards various causes. Crucial for the situation at the rural areas are the changed trajectories of cyclones and anticyclones as well as the decline of the atmospheric oxidation-capacity, while the traffic plays another important role at urban stations. The negative trend at the traffic-stations was intensified by the introduction of catalytic converters, which lead to a reduction in emissions of NOxRecommendations and prospects
The significance of the NO/NO2-ratio for the oxidation capacity of the atmosphere shows the necessity to further monitor this development. Previous investigations detected a decline in total NOx without examining the relative development of the two nitrogen oxides towards each other. Gaining insight into the local differences of this ratio helps to allocate sources and to develop understanding of the atmospheric processes. 相似文献93.
Characterization and reactivity assessment of organic substrates for sulphate-reducing bacteria in acid mine drainage treatment 总被引:4,自引:0,他引:4
Acid mine drainage (AMD), which contains high concentrations of sulphate and dissolved metals, is a serious environmental problem. It can be treated in situ by sulphate reducing bacteria (SRB), but effectiveness of the treatment process depends on the organic substrate chosen to supply the bacteria's carbon source. Six natural organic materials were characterized in order to investigate how well these promote sulphate reduction and metal precipitation by SRB. Maple wood chips, sphagnum peat moss, leaf compost, conifer compost, poultry manure and conifer sawdust were investigated in terms of their carbon (TOC, TIC, DOC) and nitrogen (TKN) content, as well as their easily available substances content (EAS). Single substrates, ethanol, a mixture of leaf compost (30% w/w), poultry manure (18% w/w), and maple wood chips (2% w/w), and the same mixture spiked with formaldehyde were then tested in a 70-day batch experiment to evaluate their performance in sulphate reduction and metal removal from synthetic AMD. Metal removal efficiency in batch reactors was as high as 100% for Fe, 99% for Mn, 99% for Cd, 99% for Ni, and 94% for Zn depending on reactive mixtures. Early metal removal (0-12d) was attributed to the precipitation of (oxy)hydroxides and carbonate minerals. The lowest metal and sulphate removal efficiency was found in the reactor containing poultry manure as the single carbon source despite its high DOC and EAS content. The mixture of organic materials was most effective in promoting sulphate reduction, followed by ethanol and maple wood chips, and single natural organic substrates generally showed low reactivity. Formaldehyde (0.015% (w/v)) provided only temporary bacterial inhibition. Although characterization of substrates on an individual basis provided insight on their chemical make-up, it did not give a clear indication of their ability to promote sulphate reduction and metal removal. 相似文献
94.
Ecological impacts and management strategies for western larch in the face of climate-change 总被引:1,自引:0,他引:1
Gerald E. Rehfeldt Barry C. Jaquish 《Mitigation and Adaptation Strategies for Global Change》2010,15(3):283-306
Approximately 185,000 forest inventory and ecological plots from both USA and Canada were used to predict the contemporary
distribution of western larch (Larix occidentalis Nutt.) from climate variables. The random forests algorithm, using an 8-variable model, produced an overall error rate of
about 2.9 %, nearly all of which consisted of predicting presence at locations where the species was absent. Genetic variation
among 143 populations within western larch’s natural distribution was predicted from multiple regression models using variables
describing the climate of the seed source as predictors and response data from two separate genetic tests: 1) 15-year height
at a field site in British Columbia, Canada, and, 2) two principal components of 8 variables describing growth, disease tolerance,
and phenology of 6-year-old trees in a test in Idaho, USA. Presence and absence of the species and genetic variation within
the species were projected into future climates provided by three General Circulation Models and two scenarios. Although the
projections described pronounced impacts on the species and its populations, concurrence among the six projections pinpointed
areas where the probability would be high that the future climate would be suitable for western larch. Concurrence among projections
also was used to locate those sources of seed that should be best attuned genetically to future climates. The procedures outline
a logical approach for developing management strategies for accommodating climate-change while taking into account the variability
imposed by the differences among climatic estimates. 相似文献
95.
96.
Aliakbar Malekuti Gerald F. Gifford 《Journal of the American Water Resources Association》1978,14(1):195-205
Abstract: Foliage and litter leachate from selected natural vegetation in the Price River Basin (within the Upper Colorado River basin) was studied to determine the probable impact of plants on the amount of diffuse salt movement from rangeland watersheds. Calculations using concentrations of various leachates and characteristics of range sites expected to be high salt annual salt load to the Price River. It was therefore concluded that plants are not a significant source of diffuse salt within the Colorado River Basin. 相似文献
97.
This study examines the motivations of mainland Chinese facilities in seeking ISO 14001 certification and examines the linkages between these motivations and self-reports of the effectiveness of major environmental management system (EMS) components. In a sample of 128 facilities in Beijing, Shanghai, and Guangzhou, the main drivers for certification were reported to be to ensure regulatory compliance, to enhance the firms reputation, and to improve environmental performance, in that order. Although motivation to achieve cost reductions were least emphasized, a broad range of motivations appears to be considered in the decision to seek certification to ISO 14001. Regression models linking these motivations to the EMS components suggests that internal motivations have an influence on most EMS components. One interesting exception to this, however, is that no significant relationship was observed between internal motivations and the promulgation of environmental objectives and targets. The relationships associated with external motivations for certification (i.e., those in response to customer and other stakeholder pressures) and EMS components, on the other hand, are weaker and tend to occur earlier in the process cycle. No significant relationships were found between motivations to reduce costs and perceptions of the effectiveness of EMS components. Overall, these findings suggest that ISO 14001, as currently being implemented in mainland China, may have a modestly useful role when used in combination with other policy mechanisms to move the Chinese economy toward more sustainable practices. It is asserted that the ISO standard could provide even greater benefits if Chinese registrars were more proactive in developing EMS in conjunction with even more rigorous third-party audits.Published online 相似文献
98.
PROBLEM: Although personality characteristics such as impulsiveness have been linked to the driving safety and driving habits of young and middle-aged adults, little research has focused on the role of personality in older driver behavior. METHOD: Using the IVE questionnaire in an exploratory study, three personality dimensions (impulsiveness, venturesomeness, and empathy) were measured in 305 older drivers (ages 57-87 years old). In addition, the Driving Habits Questionnaire was used to estimate driving exposure, and the Driver Behavior Questionnaire (DBQ) was used to estimate driving errors and violations. State-recorded crash data were made available by the state public safety agency. RESULTS: Subjects who reported four or more driving errors had higher impulsivity and empathy scores and lower venturesomeness scores. Subjects reporting driving violations were more likely to have high impulsivity scores. Driving six or more places per week was associated with lower levels of impulsivity. IMPACT: These results suggest that a comprehensive understanding of driving problems among older adults should also include a consideration of personality dimensions. In doing so, the challenges faced in the interpretation of self-report instruments on driving behaviors must be acknowledged, with a move in research toward greater reliance on more objective measures of driving behavior when assessing the impact of personality variables. 相似文献
99.
Gerald T. Ankley Nelson A. Thomas Dominic M. Di Toro David J. Hansen John D. Mahony Walter J. Berry Richard C. Swartz Robert A. Hoke A. Wayne Garrison Herbert E. Allen Christopher S. Zarba 《Environmental management》1994,18(3):331-337
Due to anthropogenic inputs, elevated concentrations of metals frequently occur in aquatic sediments. In order to make defensible
estimates of the potential risk of metals in sediments and/or develop sediment quality criteria for metals, it is essential
to identify that fraction of the total metal in the sediments that is bioavailable. Studies with a variety of benthic invertebrates
indicate that interstitial (pore) water concentrations of metals correspond very well with the bioavailability of metals in
test sediments. Many factors may influence pore water concentrations of metals; however, in anaerobic sediments a key phase
controlling partitioning of several cationic metals (cadmium, nickel, lead, zinc, copper) into pore water is acid volatile
sulfide (AVS). In this paper, we present an overview of the technical basis for predicting bioavailability of cationic metals
to benthic organisms based on pore water metal concentrations and metal-AVS relationships. Included are discussions of the
advantages and limitations of metal bioavailability predictions based on these parameters, relative both to site-specific
assessments and the development of sediment quality criteria. 相似文献
100.
Legally designated wilderness areas are acknowledged to be an important element in strategies to conserve biological diversity
in United States. However, because of the restrictions on consumptive uses in wilderness, their establishment is normally
contentious. Criteria for establishment have typically been associated with opportunity and aesthetic and experiential values.
Biological data have not normally played a major role in guiding wilderness establishment. We present four wilderness allocation
options for those public lands considered suitable for wilderness designation in Idaho. These options cover the span of choices
presently available to wilderness planners in the state and range from not establishing any new wilderness areas to the inclusion
of all suitable lands in wilderness. All options are evaluated using spatial biological data from the National Biological
Survey's Gap Analysis Project. A conservation strategy that would protect a minimum of 10% of the area occupied by each of
113 native vegetation types and at a minimum 10% of the distribution of each of 368 vertebrate species was evaluated for each
option. Only the inclusion of all suitable lands in wilderness, creating a system of 5.1 million ha came close to achieving
these goals, protecting 65% of the vegetation types and 56% of the vertebrate species. We feel this approach, which allows
planners to evaluate the ecological merits of proposed widerness units along with other values, can provide a means to resolve
the impasse over additional wilderness designation in Idaho. 相似文献