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661.
Kristen A. Conner Author Vitae Author Vitae Jonathan I. Groner Author Vitae Author Vitae 《Journal of Safety Research》2008,39(5):469-475
Problem
Motorized recreational vehicle (MRV)-related injuries can result in severe medical and financial consequences. The objective of this study was to describe the epidemiology, and clinical and financial impact of MRV-related injuries in Ohio.Method
Probabilistically linked statewide Emergency Medical Services (EMS) and hospital (inpatient and emergency department) data for 2003 and 2004 were examined. Record pairs with a MRV-related E-code (E821-E823, E825) were included in this study.Results
There were 2,893 patients with MRV-related injuries, who had linked EMS and hospital records, resulting in more than $15 million in hospital charges and 1,921 inpatient days of hospitalization. The male-to-female ratio was nearly 4:1, and 19% were younger than 16. Almost 82% of cases were not wearing a helmet; there was a trend of decreasing helmet use with increasing age. Mean (SE) inpatient hospital charges and length of stay (LOS) were $22,218 ($1,290) and 3.8 (0.2) days, respectively. The mean (SE) Injury Severity Score (ISS) for inpatients was 9.2 (0.4). Individuals injured on a street/highway were 3.20 times more likely to sustain an ISS ≥ 16 (95% CI: 1.03, 9.88; p = 0.044) and 3.05 times more likely to sustain a traumatic brain injury (TBI) (95% CI: 1.17, 7.94; p = 0.024) than those who were injured at a place designated for sport or recreation. Children aged 12 to 15 and young adults aged 16 to 25 were 2.47 and 2.14 times more likely, respectively, to sustain a TBI than adults aged 36 or older (aged 12 to 15: 95% CI: 1.13, 5.38; p = 0.024; aged 16 to 25: 95% CI: 1.26, 3.64; p = 0.005). Higher ISS was associated with both higher total charges (p < 0.001) and longer LOS (p < 0.001).Discussion
This study demonstrates that MRV-related injuries are an important public health problem in Ohio, with a substantial clinical and financial impact.Impact on Industry
Enactment and enforcement of statewide MRV safety legislation and training of MRV users offer valuable opportunities to prevent these costly injuries. 相似文献662.
Edward D. Frank Amgad Elgowainy Jeongwoo Han Zhichao Wang 《Mitigation and Adaptation Strategies for Global Change》2013,18(1):137-158
Algae biomass is an attractive biofuel feedstock when grown with high productivity on marginal land. Hydrothermal liquefaction (HTL) produces more oil from algae than lipid extraction (LE) does because protein and carbohydrates are converted, in part, to oil. Since nitrogen in the algae biomass is incorporated into the HTL oil, and since lipid extracted algae for generating heat and electricity are not co-produced by HTL, there are questions regarding implications for emissions and energy use. We studied the HTL and LE pathways for renewable diesel (RD) production by modeling all essential operations from nutrient manufacturing through fuel use. Our objective was to identify the key relationships affecting HTL energy consumption and emissions. LE, with identical upstream growth model and consistent hydroprocessing model, served as reference. HTL used 1.8 fold less algae than did LE but required 5.2 times more ammonia when nitrogen incorporated in the HTL oil was treated as lost. HTL RD had life cycle emissions of 31,000 gCO2 equivalent (gCO2e) compared to 21,500 gCO2e for LE based RD per million BTU of RD produced. Greenhouse gas (GHG) emissions increased when yields exceeded 0.4 g HTL oil/g algae because insufficient carbon was left for biogas generation. Key variables in the analysis were the HTL oil yield, the hydrogen demand during upgrading, and the nitrogen content of the HTL oil. Future work requires better data for upgrading renewable oils to RD and requires consideration of nitrogen recycling during upgrading. 相似文献
663.
664.
Peter R. Brown Neil I. Huth Peter B. Banks Grant R. Singleton 《Agriculture, ecosystems & environment》2007,120(2-4):405-415
Developing a relationship between pest abundance and damage to crops is essential for the calculation of economic injury levels (EIL) leading to informed management decisions. The crop modelling framework, APSIM, was used to simulate the impact of mouse damage on yield loss on wheat where a long-term dataset on the density of mice was available (1983–2003). The model was calibrated using results from field trials where wheat plants were hand clipped to imitate mouse damage. The grazing effect of mice was estimated using the population density, daily intake per mouse and the proportion of wheat grain and plant tissue in the diet to determine yield loss. The mean yield loss caused by mice was 12.4% (±5.4S.E.; range −0.5 to 96%). There were 7/21 years when yield loss was >5%. A damage/abundance relationship was constructed and a sigmoidal curve explained 97% of variation when accounting for different trajectories of mouse densities from sowing to harvest. The majority of damage occurred around emergence of the crop when mouse densities were >100 mice ha−1. This is the first time that field data on mouse density and a crop simulation model have been combined to estimate yield loss. The model examines the efficacy of baiting and how to estimate EILs. Because the broadscale application of zinc phosphide is cheap and effective, the EIL is very low (<1% yield loss). The APSIM model is highly flexible and could be used for other vertebrate pests in a range of crops or pastures to develop density/damage relationships and to assist with management. 相似文献
665.
A. Araya P.V.V. Prasad P.H. Gowda I. Kisekka A.J. Foster 《Journal of the American Water Resources Association》2019,55(1):24-37
The Agricultural Production Systems sIMulator model validated in a prior study for winter wheat was used to simulate yield, aboveground crop biomass (BM), transpiration (T), and evapotranspiration under four irrigation capacities (ICs) (0, 1.7, 2.5, and 5 mm/day) with two nitrogen (N) application rates (N1, 94 kg N/ha; N2, 160 kg N/ha) to (1) understand the performance of winter wheat under different ICs and (2) develop crop water production function under various ICs and N rates. Evaluation was based on yield, aboveground crop BM, transpiration productivity (TP), crop water productivity (WP), and irrigation WP (IWP). Simulation results showed winter wheat yield increased with increase in N application rate and IC. However, the rate of yield increase gradually reduced with additional irrigation beyond 2.5 mm/day. A 5 mm/day IC required a total of 190 mm irrigation and produced a 5%–16% yield advantage over 2.5 mm/day. This indicates it is possible to reduce groundwater use for wheat by 50% incurring only 5%–16% yield loss relative to 5 mm/day. The TP and IWP for grain were slightly higher under IC of 1.7 mm/day (15.2–16.1 kg/ha/mm and 0.98–1.6 kg/m3) when compared to 5 mm/day (14.7–15.5 kg/ha/mm and 0.6–1.06 kg/m3), respectively. Since TP and IWPs are relatively higher under lower ICs, winter wheat could be a suitable crop under lower ICs in the region. Relationship between yield–T and yield–ET was linear with a slope of 15–16 and 9.5–10 kg/ha/mm, respectively. Editor's note : This paper is part of the featured series on Optimizing Ogallala Aquifer Water Use to Sustain Food Systems. See the February 2019 issue for the introduction and background to the series. 相似文献
666.
David I.S. Green Samuel M. McDeid William G. Crumpton 《Journal of the American Water Resources Association》2019,55(3):543-558
We present estimates of the volumetric storage capacities of currently drained upland depressions and catchment depressional specific storage and runoff storage indices for the Des Moines Lobe of Iowa (DML‐IA) subregion of the Prairie Pothole Region of North America. Storage capacities were determined using hydrologically enforced Light Detection and Ranging‐derived digital elevation models, and a unique geoprocessing algorithm. Depressional specific storage was estimated for each 12‐digit Hydrologic Unit Code (HUC12) watershed in the region from total catchment‐specific depressional storage volume and catchment area. Runoff storage indices were calculated using catchment depressional specific storage values and estimates of the amount of rainfall likely to fall within each watershed during sub‐annual and 1‐, 2‐, 5‐, and 10‐year 24‐h events. The 173,171 identified drained depressions in the DML‐IA can store up to 903.5 Mm3 of runoff. Most of this capacity is in depressions located in the north of the region. Specific storage varies from nearly 109 mm in the younger landscapes to <10 mm in older more eroded areas. For 95% of the HUC12 watersheds comprising the region, depressional storage will likely be exhausted by rainfall‐derived runoff in excess of a 1‐year 24‐h event. Rainfall amounts greater than a 5‐year 24‐h event will exceed all available depressional storage. Therefore, the capacity of drained depressions in the DML‐IA to mitigate flooding resulting from infrequent, but large, storm events is limited. 相似文献
667.
The coupled SWAP-WOFOST model was used to study the effects of increasing salinity of groundwater, drought and water excess on grass production in The Netherlands. WOFOST simulates crop growth and SWAP simulates transport of water, solutes and heat in the vadose zone. The model was tested using several datasets from field experiments. We applied the models at regional scale where we quantified the impact of various groundwater salinity levels on grass growth and production using historical weather data (1971-2000). The salt concentrations in the subsoil were derived from the National Hydrological Instrument. The results show that salinity effects on grass production are limited. In wet years the excess rainfall will infiltrate the soil and reduce salt water seepage. In a next step we used future weather data for the year 2050, derived from 3 Global Circulation Models. From each model we used data from two CO2 emission scenarios. As expected higher temperatures increased drought stress, however, the production reduction as a result of salt water in the root zone is limited. Salt stress mainly occurred when irrigation was applied with saline water. The increased CO2 concentration in combination with the limited drought stress resulted in increasing simulated actual and potential yields. Overall conclusion for grassland in The Netherlands: drought stress is stronger than stress caused by water excess which on its turn is stronger than salinity stress. Future water demand for irrigation may increase by 11-19% and result in water scarcity if water supply is insufficient. 相似文献
668.
Although many parasites are known to manipulate the behavior of their hosts, the mechanisms underlying such manipulations are largely unknown. Baculoviruses manipulate the behavior of caterpillar hosts by inducing hyperactivity and by inducing climbing behavior leading to death at elevated positions (tree-top disease or Wipfelkrankheit). Whether hyperactivity and tree-top disease are independent manipulative strategies of the virus is unclear. Recently, we demonstrated the involvement of the protein tyrosine phosphatase (ptp) gene of the baculovirus Autographa californica multiple nucleopolyhedrovirus (AcMNPV) in the induction of hyperactivity in Spodoptera exigua larvae. Here we show that AcMNPV ptp is not required for tree-top disease, indicating that in S. exigua baculovirus-induced hyperactivity and tree-top disease are independently induced behaviors that are governed by distinct mechanisms. 相似文献
669.
This study investigated the water quality variation spanning 30 years (1986–2017) in 16 catchments of Hong Kong against different urbanization indices, namely, built area fraction; population; and product of population and built area fraction. Pearson correlations of three different periods of time (1988–1990, 1998–2000, and 2015–2017) indicated that water quality trends were dependent on the urbanization index. Total solids, nitrite-nitrogen, total phosphorus, electrical conductivity, dissolved oxygen, and flow rate had significant deteriorative trends (Pearson r > 0.5 and p < 0.05) with population and product of built area and population. Results also interpreted that built area fraction and product of built area and population were the worst and best indices that represented urbanization and/or its impacts, respectively. Mann-Kendall test for the entire 30 year period showed that water quality had improved with time with respect to certain water quality parameters (e.g., dissolved oxygen, ammoniacal nitrogen and total suspended solids). The results portrayed that although the urbanization of catchments had increased with time, the river water quality with respect to many parameters showed signs of improvement and the legislative measures implemented seemed to be effective in controlling pollution. 相似文献
670.
In this laboratory study different combinations of bed (sand, pebble gravel [gravel], and a mix of sand and gravel) and flow (typical and overtopping) were experimented with to investigate the impact of porous deflectors in flow diversity, water quality, and fish performance in prismatic open channels. Deflectors changed the gradually varied flow to a rapidly varied flow, as a sudden change in the water depth was observed at the deflectors, and this change was large for smooth beds. With the presence of gravel, the scouring near the downstream deflector was almost twice that of the sand bed, and with the scouring at its own upstream deflector, irrespective of whether the flow was typical or overtopping. This behavior was a result of sand mobilization due to shear stress and sand mobilization aided gravel transport. The mixed bed showed less gravel movement compared to the gravel-only bed. The percentage of sediment washed out was minor for all bed scenarios, indicating that sediment transport was local. Relative to the sand bed without deflectors (representing a typical urban canal), deflectors resulted in reduced and improved water quality (in terms of sediment load) for sand, and mixed bed, respectively. The fishes found refuge and were comfortable in the pool areas created by deflectors unlike in channels without deflectors where they showed exhaustion. 相似文献