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491.
Objective: The purpose of this study was to use the detailed medical injury information in the Crash Injury Research and Engineering Network (CIREN) to evaluate patterns of rib fractures in real-world crash occupants in both belted and unbelted restraint conditions. Fracture patterns binned into rib regional levels were examined to determine normative trends associated with belt use and other possible contributing factors.Methods: Front row adult occupants with Abbreviated Injury Scale (AIS) 3+ rib fractures, in frontal crashes with a deployed frontal airbag, were selected from the CIREN database. The circumferential location of each rib fracture (with respect to the sternum) was documented using a previously published method (Ritchie et al. 2006) and digital computed tomography scans. Fracture patterns for different crash and occupant parameters (restraint use, involved physical component, occupant kinematics, crash principal direction of force, and occupant age) were compared qualitatively and quantitatively.Results: There were 158 belted and 44 unbelted occupants included in this study. For belted occupants, fractures were mainly located near the path of the shoulder belt, with the majority of fractures occurring on the inboard (with respect to the vehicle) side of the thorax. For unbelted occupants, fractures were approximately symmetric and distributed across both sides of the thorax. There were negligible differences in fracture patterns between occupants with frontal (0°) and near side (330° to 350° for drivers; 10° to 30° for passengers) crash principal directions of force but substantial differences between groups when occupant kinematics (and contacts within the vehicle) were considered. Age also affected fracture pattern, with fractures tending to occur more anteriorly in older occupants and more laterally in younger occupants (both belted and unbelted).Conclusions: Results of this study confirmed with real-world data that rib fracture patterns in unbelted occupants were more distributed and symmetric across the thorax compared to belted occupants in crashes with a deployed frontal airbag. Other factors, such as occupant kinematics and occupant age, also produced differing patterns of fractures. Normative data on rib fracture patterns in real-world occupants can contribute to understanding injury mechanisms and the role of different causation factors, which can ultimately help prevent fractures and improve vehicle safety. 相似文献
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493.
Periann P. Russell Susan M. Gale Breda Muñoz John R. Dorney Matthew J. Rubino 《Journal of the American Water Resources Association》2015,51(1):226-239
Headwater streams are the primary sources of water in a drainage network and serve as a critical hydrologic link between the surrounding landscape and larger, downstream surface waters. Many states, including North Carolina, regulate activity in and near headwater streams for the protection of water quality and aquatic resources. A fundamental tool for regulatory management is an accurate representation of streams on a map. Limited resources preclude field mapping every headwater stream and its origin across a large region. It is more practical to develop a model for headwater streams based on a sample of field data that can then be extrapolated to a larger area of interest. The North Carolina Division of Water Quality has developed a cost‐effective method for modeling and mapping the location, length, and flow classification (intermittent and perennial) of headwater streams. We used a multiple logistic regression approach that combined field data and terrain derivatives for watersheds located in the Triassic Basins ecoregion. Field data were collected using a standard methodology for identifying headwater streams and origins. Terrain derivatives were generated from digital elevation models interpolated from bare‐earth Light Detection and Range data. Model accuracies greater than 80% were achieved in classifying stream presence and absence, stream length and perennial stream length, but were not as consistent in predicting intermittent stream length. 相似文献
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496.
Socioeconomic indicators and the survival of the tropical rainforest of cross river state of Nigeria
An internal household survey of socioeconomic indicators in the Cross River State forest communities showed that basic infrastructural
facilities such as clean water supply, adequate waste disposal system, good roads and electricity are grossly inadequate.
There is a total absence of modern family planning practices in the communities, and population is projected to increase by
44.8% between 2000 and 2015 and 85.4% between 2000 and 2025. The study revealed that about 65% of the population of the rainforest
communities consists of subsistence farmers and power chain operators, and besides the 19% of the Cross River State Tropical
High Forestry (THF) already reported to have been lost to agriculture and plantation between 1972 and 1991, about 9% was lost
between 1991 and 2000. An additional 25% of the THF will be lost by 2025, leaving only 470600 hectares (4706 km2). With 84.1% of community members having an annual income less than $300, the survival potential of the Cross River State
rainforest in the next fifty years is very low, unless an effective forest management programme is encouraged by government
in partnership with all stakeholders. 相似文献
497.
Matthew J. Kiernan 《环境质量管理》2001,10(4):1-12
Contrary to popular assumptions, superior eco‐efficiency is associated with superior financial performance throughout a range of industries. In fact, environmental leaders typically outperform laggards by a substantial margin. © 2001 John Wiley & Sons, Inc. 相似文献
498.
John J. Gagliardi Don Kim Jennifer J. Sokol Larry A. Zazzera Vincent D. Romero Matthew R. Atkinson Faisal Nabulsi Harry Zhang 《Journal of Manufacturing Processes》2013,15(3):348-354
An alternative, and potentially better, means to process prime LED sapphire wafers is proposed. A brief history of material removal mechanisms suggests that brittle materials can be abraded in a ductile regime and that this can be a superior mode of removal. Advantages in material removal rate, surface finish and subsurface damage for a 2-body ductile removal of sapphire are shown relative to 3-body material removal. A major difficulty with this approach may be getting the LED manufacturing industry to understand that the appearance of the sapphire surface is quite different, unfamiliar yet predictable. Finally, some potential alternative process approaches are discussed that utilize 2-body material removal. 相似文献
499.
W. Matthew Vander Haegen Frederick C. Dobler D. John Pierce 《Conservation biology》2000,14(4):1145-1160
Abstract: The landscape of the intermountain west has changed dramatically in the last 150 years, particularly in the state of Washington, where over half the native shrubsteppe ecosystem has been converted to agricultural lands, resulting in a fragmented landscape with few extensive tracts of shrubsteppe. We examined the historical and current distribution of shrubsteppe on different soil types in eastern Washington, and we censused bird communities at 78 sites in shrubsteppe from 1991 to 1993. We compared abundance of species among soil types and range conditions and developed models of species occurrence using site-specific vegetation and landscape variables. The pattern of shrubsteppe conversion has resulted in a disproportionate loss of deep soil communities. Eight bird species showed strong relationships with soil type and three with range condition. These associations likely resulted from the influence of soil type and range history on the vegetation of these communities. Brewer's Sparrows ( Spizella breweri ) and Sage Sparrows ( Amphispiza belli ) reached their highest abundances in deep, loamy soils, whereas Loggerhead Shrikes ( Lanius ludovicianus ) were most abundant in deep, sandy soils. Sage Sparrows occurred more frequently in landscapes dominated by shrubsteppe, indicating a negative relationship with fragmentation. Our results suggest that fragmentation of shrubsteppe and the pattern of agricultural conversion among soil types have had detrimental effects on numerous shrubsteppe species. The landscape for species with an affinity for deep, loamy soil communities has changed considerably more than the overall loss of shrubsteppe would indicate. Conservation practices that emphasize retention of shrubsteppe communities on deep soils and that reduce further fragmentation will be critical to the maintenance of avian biological diversity in this system. 相似文献
500.
Tischa A. Muñoz-Erickson Bernardo Aguilar-González Matthew R. R. Loeser Thomas D. Sisk 《Environmental management》2010,45(1):132-144
As collaborative groups gain popularity as an alternative means for addressing conflict over management of public lands, the
need for methods to evaluate their effectiveness in achieving ecological and social goals increases. However, frameworks that
examine both effectiveness of the collaborative process and its outcomes are poorly developed or altogether lacking. This
paper presents and evaluates the utility of the holistic ecosystem health indicator (HEHI), a framework that integrates multiple
ecological and socioeconomic criteria to evaluate management effectiveness of collaborative processes. Through the development
and application of the HEHI to a collaborative in northern Arizona, the Diablo Trust, we present the opportunities and challenges
in using this framework to evaluate the ecological and social outcomes of collaborative adaptive management. Baseline results
from the first application of the HEHI are presented as an illustration of its potential as a co-adaptive management tool.
We discuss lessons learned from the process of selecting indicators and potential issues to their long-term implementation.
Finally, we provide recommendations for applying this framework to monitoring and adaptive management in the context of collaborative
management. 相似文献