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Objectives: Though there is a growing body of literature on crash risks in the developed world, little is known about how well these models apply to motoring in developing countries, the context in which the majority of road traffic fatalities occur. This qualitative study explores factors perceived to influence crash risks for commercial drivers in Ghana.

Method: Twenty commercial drivers of varied ages and experience were sampled from 7 major lorry terminals in 3 regions (Greater Accra, Ashanti, and Volta) of Ghana. Data were collected through semistructured interviews.

Results: The participants identified some issues that are shared with drivers in the developed world, though moderated by the Ghanaian context. These included work pressures (e.g., fatigued driving), speeding, distracted driving, and inadequate vehicle maintenance. Other factors identified by participants are less frequently considered in research addressing driving behavior in developed countries. These included aggressive competition over passengers and corruption (e.g., improper licensing practices), among others.

Conclusion: The findings have implications for building a research base to support the development of road safety policy and interventions in developing countries.  相似文献   

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Jones RP  Millward RN  Karn RA  Harrison AH 《Chemosphere》2006,62(11):1795-1805
Microscale methods (MM) were evaluated and compared to traditional methods (TM) for measuring polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in spiked and standard reference fish and mussel tissues. MMs are advantageous because they use small tissue masses (ca. 100 mg), and maintain sensitivity through reducing final extract volume (traditionally 1 ml) by an order of magnitude or more (40 μl—PCBs; 100 μl—PAHs). Procedural losses occurred in the MMs’ combined cleanup/primary evaporation step (19% PAHs; 6% PCBs), and the final extract concentration (14% PAHs; 22% PCBs). The PAH MM performed comparably to the TM. Although most PCBs had recoveries >50%, the PCB MM generally yielded lower recoveries than the TM. Average method detection limits were 0.6 μg/kg (TM) and 1.0 μg/kg (MM) for PCBs and 25.7 μg/kg (TM) and 27.7 μg/kg (MM) for PAHs. MMs described for PCB and PAH tissue samples are potentially viable alternatives to TMs, and could lead to cost savings in bioaccumulation/toxicity tests.  相似文献   
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The relationship between migration and deforestation in the developing world continues to receive significant attention. However beyond direct population increase, the precise mechanisms that operate within the intersection of migrant/host land rights remain largely unexamined. Where migrants are provided with land and rights by the State and/or local communities, how such rights are perceived by the migrants is of primary importance in their interaction with land resources, and in aggregate it impacts the development opportunities and environmental repercussions of migration. The authors analyze the operative aspects of land rights reception (as opposed to provision) by migrant populations, and the relationship between this reception and deforestation. The article examines a case in Zambia to analyze how tenurial constructs, emerging from the way rights are perceived by migrants, lead to the continued clearing of areas much larger than needed for cultivation, even when the arrangement appears counter‐productive in terms of land rights provision and labour allocation. While valuable policy efforts have focused on providing resource rights to migrants, how such rights are received and the relationship of this reception to resource management needs greater policy attention.  相似文献   
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The strategic use of science in regional policy-making forums often assumes collaborative interactions between stakeholders. However, other types of stakeholder interactions are possible. This paper uses the ecology of games to frame an investigation into stakeholder participation in the policy networks for regional climate change planning for South East Queensland, Australia. We tracked organisational participation in policy forums between 2008 and 2012. We then used a novel bipartite network theoretical approach to identify participation by different types of organisations across shared multiple forums, which we argue prefaces: cooperation, collaboration, support or advocacy. Network analysis was then combined with semi-structured interviews to access how scientific information was utilised across the regional network. Our results suggest that stakeholder interactions were predominately used to advocate for organisational agendas. Advocacy artificially narrows the scope of possible policy options and represents a biased, selective use of information. While advocacy is an important part of policy process, as a counter balance, explicit efforts are needed to recurrently expand the scope of policy options.  相似文献   
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When annual average PM2.5 (fine particulate matter sized 2.5 microns and less) data for 2005 became available in April 2006 and the 3-yr average PM2.5 concentration in an area just north of the Houston Ship Channel reached 15.0 µg/m3, the Texas Commission on Environmental Quality (TCEQ) initiated daily collection of quartz fiber as well as Teflon PM2.5 filter samples for chemical speciation analysis. The purpose of the chemical speciation analysis was to use the speciation data, together with meteorological data and hourly TEOM (tapered element oscillating microbalance) PM2.5 mass data, to identify the causes of the high PM2.5 concentrations affecting the monitoring site and the neighborhood. The ultimate purpose was to target emission reduction efforts to sources contributing to the high measured PM2.5 concentrations. After a year of data collection, it was recognized that a specific source, unpaved driveways and loading areas along the Ship Channel and dirt tracked onto Clinton Drive, the main artery running east-west north of the Ship Channel, were the primary cause for the Clinton Drive site's measuring PM2.5 concentrations significantly higher than other sites in Houston. The source characterization and remediation steps that have led to sustained reduced concentrations are described in this paper.

Implications: With PM2.5 exceedances it can be essential to have or develop chemical speciation data as part of the process of identifying the source types causing exceedances of an annual standard. Positive matrix factorization (PMF) analysis proved to be a powerful tool that identified the two locally emitted species contributing to exceedances, which did not occur at other sites in the region. They were calcium sulfate (gypsum), an industrial by-product, and soil minerals. Other data analysis approaches were necessary to distinguish North African dust events, which PMF failed to identify.  相似文献   
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We report the application of an infrared (IR) differential absorption Lidar (DIAL) system (also capable of ultra violet measurements) built at the National Physical Laboratory (NPL), UK, to field measurements of total site emissions (controlled and fugitive) from petrochemical and landfill installations. The validation of the IR-DIAL was carried out via a series of controlled field experiments including comparison to GC analysis and tests against controlled methane releases from a test stack, all detailing agreements on the order of ±20%. In volatile organic compound (VOC) measurements at a UK petrochemical site it was found that the American Petroleum Institute's methodology of the time for calculating the emitted flux underestimated by a factor of 2.4. Also, in a similar field trial it was found that scaling traditional point measurements at easily accessible flanges and valves to represent all flanges and valves on a site led to an underestimation by a factor of 6. In addition to petrochemical examples we also report field measurements from a landfill site to demonstrate the advantageous of the DIAL technique for monitoring area emission sources. In this case study it was found that active (still being filled) cells resulted in significantly greater VOC emission rates (30 kg h(-1)) than closed (≤ 10 kg h(-1)).  相似文献   
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