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21.
Objectives: A better understanding of the long-term factors that independently predict poorer quality of life following mild to moderate musculoskeletal injuries is needed. We aimed to establish the predictors of quality of life (including sociodemographic, health, psychosocial, and pre-injury factors) 24 months after a noncatastrophic road traffic injury.

Methods: In a prospective cohort study of 252 participants with mild/moderate injury sustained in a road traffic crash, quality of life was measured 24 months following the baseline survey. A telephone-administered questionnaire obtained information on various potential explanatory variables. Health-related quality of life was measured using the European Quality of Life–5 Dimensions (EQ-5D) and Medical Outcomes Survey Short Form–12 (SF-12). Multivariable linear regression analyses determined the associations between explanatory variables and quality of life measures.

Results: Mean SF-12 physical component summary (PCS) and mental component summary (MCS) scores increased by 7.3 and 2.5 units, respectively, from baseline to 24-month follow-up. Each 10-year increase in baseline age was independently associated with 3.1-unit (P < .001) and 1.5-unit (P = .001) decrease in EQ Visual Analogue Scale (VAS) and SF-12 PCS scores at follow-up, respectively. Poor/fair compared to excellent pre-injury health was associated with a 0.16-, 21.3-, and 11.5-unit decrease in EQ-5D summary (P = .03), VAS scores (P = .001), and SF-12 PCS scores (P < .001), respectively. Baseline pain severity ratings and pain catastrophizing scores were inversely associated with 24-month EQ VAS scores (both P < .001). Each unit increase in baseline pain score (P = .001) and pain catastrophizing score (P = .02) was associated with a 1.0- and 4.6-unit decrease in SF-12 MCS scores at 24 months, respectively. Other observed predictors of quality of life measures (EQ-5D summary and/or VAS scores and/ or SF-12 MCS) included marital status, smoking, hospital admission, pre-injury health (anxiety/depression and chronic illness), and whiplash injury.

Conclusion: Sociodemographic indicators, pre-injury health, and biopsychosocial correlates were independently associated with health-related quality of life 24 months following a noncatastrophic road traffic crash injury.  相似文献   

22.
Urea‐N is a component of bioavailable dissolved organic nitrogen (DON) that contributes to coastal eutrophication. In this study, we assessed urea‐N in baseflow across land cover gradients and seasons in the Manokin River Basin on the Delmarva Peninsula. From March 2010 to June 2011, we conducted monthly sampling of 11 streams (4 tidal and 7 nontidal), 2 wastewater treatment plants, an agricultural drainage ditch, and groundwater underlying a cropped field. At each site, we measured urea‐N, DON, dissolved organic carbon (DOC), total dissolved nitrogen (TDN), NO3?‐N, and NH4+‐N. In general, urea‐N comprised between 1% and 6% of TDN, with the highest urea‐N levels in drainage ditches (0.054 mg N/L) and wetland‐dominated streams (0.035–0.045 mg N/L). While urea‐N did not vary seasonally in tidal rivers, nontidal streams saw distinct urea‐N peaks in summer (0.038 mg N/L) that occurred several months after cropland fertilization in spring. Notably, the proportion of wetlands explained 78% of the variance in baseflow urea‐N levels across the Manokin watershed. In wetland‐dominated basins, we found urea‐N was positively related to water temperature and negatively related to DOC:DON ratios, indicating short‐term urea‐N dynamics at baseflow were more likely influenced by instream and wetland‐driven processes than by recent agricultural urea‐N inputs. Findings demonstrate important controls of wetlands on baseflow urea‐N concentrations in mixed land‐use basins.  相似文献   
23.
Highway runoff has the potential to negatively impact receiving systems including stormwater retention ponds where highway particulate matter can accumulate following runoff events. Tire wear particles, which contain about 1% Zn by mass, make up approximately one-third of the vehicle derived particulates in highway runoff and therefore may serve as a stressor to organisms utilizing retention ponds as habitat. In this study, we focused on the potential contribution of tire debris to Zn accumulation by Rana sylvatica larvae and possible lethal or sublethal impacts resulting from exposure to weathered tire debris during development. Eggs and larvae were exposed to aged sediments (containing either ZnCl2 or tire particulate matter, both providing nominal concentrations of 1000 mg Zn kg(-1)) through metamorphosis. Water column Zn was elevated in both the ZnCl2 and tire treatments relative to the control treatment, indicating that aging allowed Zn leaching from tire debris to occur. Tissue Zn was also elevated for the ZnCl2 and tire treatments indicating that Zn in the treatments was available for uptake by the amphibians. Exposure to both ZnCl2 and tire treatments increased the time for larvae to complete metamorphosis in comparison with controls. We also observed that the longer the organisms took to complete metamorphosis, the smaller their mass at metamorphosis. Our results indicate that Zn leached from aged tire debris is bioavailable to developing R. sylvatica larvae and that exposure to tire debris amended sediments can result in measurable physiological outcomes to wood frogs that may influence population dynamics.  相似文献   
24.
Spring flooding of the Red River of the North (RR) is common, but little information exits on how these flood events affect water and overbank sediment quality within an urban area. With the threat of the spring 2009 flood in the RR predicted to be the largest in recorded history and the concerns about the flooding of farmsteads, outbuildings, garages, and basements, the objectives of this study, which focused on Fargo, ND, and Moorhead, MN, were to assess floodwater quality and to determine the quantity and quality of overbank sediment deposited after floodwaters recede and the quality of soil underlying sediment deposits. 17β-Estradiol was detected in 9 of 24 water samples, with an average concentration of 0.61 ng L. Diesel-range organics were detected in 8 of 24 samples, with an average concentration of 80.0 μg L. The deposition of sediment across locations and transects ranged from 2 to 10 kg m, and the greatest mass deposition of chemicals was closest to the river channel. No gasoline-range organics were detected, but diesel-range organics were detected in 26 of the 27 overbank sediment samples (maximum concentration, 49.2 mg kg). All trace elements detected in the overbank sediments were within ranges for noncontaminated sites. Although flooding has economic, social, and environmental impacts, based on the results of this study, it does not appear that flooding in the RR in F-M led to decreased quality of water, sediment, or soil compared with normal river flows or resident soil.  相似文献   
25.
This study evaluated the chemical fractionation of Cu and Zn from source to deposition in a stormwater system. Cu and Zn concentrations and chemical fractionation were determined for roadway dust, roadway runoff and pond sediments. Stormwater Cu and Zn concentrations were used to generate cumulative frequency distributions to characterize potential exposure to pond-dwelling organisms. Dissolved stormwater Zn exceeded USEPA acute and chronic water quality criteria in approximately 20% of storm samples and 20% of the storm duration sampled. Dissolved Cu exceeded the previously published chronic criterion in 75% of storm samples and duration and exceeded the acute criterion in 45% of samples and duration. The majority of sediment Cu (92-98%) occurred in the most recalcitrant phase, suggesting low bioavailability; Zn was substantially more available (39-62% recalcitrant). Most sediment concentrations for Cu and Zn exceeded published threshold effect concentrations and Zn often exceeded probable effect concentrations in surface sediments.  相似文献   
26.
Mine tailings are moderately to severely impacted sites that lack normal plant cover, soil structure and development, and the associated microbial community. In arid and semiarid environments, tailings and their associated contaminants are prone to eolian dispersion and water erosion, thus becoming sources of metal contamination. One approach to minimize or eliminate these processes is to establish a permanent vegetation cover on tailings piles. Here we report a revegetation trial conducted at a moderately impacted mine tailings site in southern Arizona. A salt and drought-tolerant plant, four-wing saltbush [Atriplex canescens (Pursh) Nutt.], was chosen for the trial. A series of 3 by 3 m plots were established in quadruplicate on the test site to evaluate growth of four-wing saltbush transplants alone or with compost addition. Results show that >80% of the transplanted saltbush survived after 1.5 yr in both treatments. Enumeration of heterotrophs and community structure analysis were conducted to monitor bacterial community changes during plant establishment as an indicator of plant and soil health. The bacterial community was evaluated using denaturing gradient gel electrophoresis (DGGE) analysis of 16S rDNA PCR gene products from tailings samples taken beneath transplant canopies. Significant differences in heterotrophic counts and community composition were observed between the two treatments and unplanted controls throughout the trial, but treatment effects were not observed. The results suggest that compost is not necessary for plant establishment at this site and that plants, rather than added compost, is the primary factor enhancing bacterial heterotrophic counts and affecting community composition.  相似文献   
27.
The great majority of China's developing towns will be extensions of already existing villages. With the prospect of hundreds of millions of Chinese farmers projected to leave their villages to become industrial workers in new and expanded towns within the next few years, new challenges will be faced. As expansion and modernization progress, this development moves from the traditional village model that operates not far from resource sustainability to increasingly unsustainable patterns of commerce, urban development, and modern life. With such an unprecedented mass migration and transformation, how can Chinese culture survive? What is to become of the existing million plus agricultural villages? How can these massively unsustainable new industrial towns survive? In the European Commission sponsored research program SUCCESS, researchers worked from the scale of the Chinese village to find viable answers to these questions.  相似文献   
28.
European Union agri-environmental schemes aim to reduce the environmental impact of agricultural production, but were developed before consideration of greenhouse gas emissions from agriculture. Life cycle assessment methodology provided a framework for comparing emissions as kg CO2 equivalent per kg of energy corrected milk (ECM) (kg CO2 kg(-1) ECM yr(-1)) and per hectare (kg CO2 ha(-1) yr(-1)) for farms both within and outside the Irish agri-environmental scheme. The agri-environmental scheme farms operate extensive systems from 40 to 120 cows producing between 3032 and 5946 kg ECM cow(-1) lactation(-1). The cows are fed on grass, conserved silage, and concentrates. Supplementation ranged between 250 and 620 kg cow(-1) yr(-1). The conventional farms had between 30 and 77 milking cows producing 4736 to 6944 kg ECM cow(-1) lactation(-1). Supplementation ranged from 400 to 1000 kg cow(-1) yr(-1). The emissions from each unit were estimated using published emissions factors and possible error was evaluated by using ranges for each factor. Calculated emissions ranged from 0.92 to 1.51 kg CO2 kg(-1) ECM yr(-1) and 5924 to 8323 kg CO2 ha(-1). On average, total emissions from conventional farms were around 18% (p = 0.01) greater than the agri-environmental scheme farms and emissions per hectare (total area required) were 17% greater (p = 0.02) but there was no significant difference (p = 0.335) in terms of emission per unit milk produced. To evaluate greenhouse gas emissions for each farm in terms of the system intensity it was necessary to define a measure of intensification and area per liter of milk produced that was best.  相似文献   
29.
Evaluation of a denitrification wall to reduce surface water nitrogen loads   总被引:1,自引:0,他引:1  
Denitrification walls have significantly reduced nitrogen concentrations in groundwater for at least 15 yr. This has spurred interest in developing methods to efficiently increase capture volume to reduce N loads in larger watersheds. The objective of this study was to maximize treatment volume by locating a wall where a large groundwatershed was funneled toward seepage slope headwaters. Nitrogen concentration and load were measured before and after wall installation in paired treatment and control streams. Beginning 2 d after installation, nitrogen concentration in the treatment stream declined from 6.7 ± 1.2 to 3.9 ± 0.78 mg L and total N loading rate declined by 65% (391 kg yr) with no corresponding decline in the control watershed. This wall, which only comprised 10 to 11% of the edge of field area that contributed to the treatment watershed, treated approximately 60% of the stream discharge, which confirmed the targeted approach. The total load reduction measured in the stream 155 m downstream from the wall (340 kg yr) was higher than that found in another study that measured load reductions in groundwater wells immediately around the wall (228 kg yr). This indicated the possibility of an extended impact on denitrification from carbon exported beyond the wall. This extended impact was inauspiciously confirmed when oxygen levels at the stream headwaters temporarily declined for 50 d. This research indicates that targeting walls adjacent to streams can effectively reduce N loading in receiving waters, although with a potentially short-term impact on water quality.  相似文献   
30.
The effects of salinity and acclimation time on the net photosynthetic responses of 3 estuarine red algae, Bostrychia radicans Mont., Caloglossa leprieurii (Mont.) J. Ag., and Polysiphonia subtilissima Mont., from Great Bay Estuary, New Jersey, USA, were investigated. The algae were cultured in a series of synthetic seawater media of 5, 15, 25 and 35% S for acclimation periods of 0, 2, 4, 8, and 16 days prior to determining their photosynthetic responses. All species were euryhaline, and demonstrated photosynthesis at all the above salinities. B. radicans, which was more common towards the mouth of the estuary, had a maximum photosynthetic rate at 25% S, whilst C. leprieurii and P. subtilissima, which were more common towards the head of the estuary, had photosynthetic maxima between 15 and 25%, and at 15%, respectively. The curves relating net photosynthesis to salinity were usually similar within a species at different acclimation periods, although statistically significant differences were sometimes noted. The acclimation periods producing maximal net photosynthesis were 0, 2 and 4 days for B. radicans, and 4 days for C. leprieurii, whilst for P. subtilissima there was no significant difference in response for any acclimation period over the range of salinities studied.  相似文献   
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