Objective: Statistics indicate that employees commuting or traveling as part of their work are overrepresented in workplace injury and death. Despite this, many organizations are unaware of the factors within their organizations that are likely to influence potential reductions in work-related road traffic injury.
Methods: This article presents a multilevel conceptual framework that identifies health investment as the central feature in reducing work-related road traffic injury. Within this framework, we explore factors operating at the individual driver, workgroup supervisor, and organizational senior management levels that create a mutually reinforcing system of safety.
Results: The health investment framework identifies key factors at the senior manager, supervisor, and driver levels to cultivating a safe working environment. These factors are high-performance workplace systems, leader–member exchange and autonomy, trust and empowerment, respectively. The framework demonstrates the important interactions between these factors and how they create a self-sustaining organizational safety system.
Conclusions: The framework aims to provide insight into the future development of interventions that are strategically aligned with the organization and target elements that facilitate and enhance driver safety and ultimately reduce work-related road traffic injury and death. 相似文献
Methylmercury(MeHg) bioaccumulation is a growing concern in ecosystems worldwide. The absorption of solar radiation by dissolved organic matter(DOM) and other photoreactive ligands can convert MeHg into less toxic forms of mercury through photodemethylation. In this study, spectral changes and photoreactivity of DOM were measured to assess the potential to control photoreactions and predict in situ MeHg concentration. Water samples collected from a series of lakes in southwestern Nova Scotia in June, August, and September were exposed to controlled ultraviolet-A(UV-A) radiation for up to 24 hr. Dissolved organic matter photoreactivity, measured as the loss of absorbance at 350 nm at constant UV-A irradiation, was positively dependent on the initial DOM concentration in lake waters(r~2=0.94). This relationship was consistent over time with both DOM concentration and photoreactivity increasing from summer into fall across lakes. Lake in situ MeHg concentration was positively correlated with DOM concentration and likely catchment transport in June(r = 0.77) but not the other sampling months. Despite a consistent seasonal variation in both DOM and Fe, and their respective correlations with MeHg, no discernable seasonal trend in MeHg was observed. However, a 3-year dataset from the 6 study lakes revealed a positive correlation between DOM concentration and both Fe(r = 0.91) and MeHg concentrations(r = 0.51) suggesting a more dominant landscape mobility control on MeHg.The DOM-MeHg relationships observed in these lakes highlights the need to examine DOM photoreactivity controls on MeHg transport and availability in natural waters particularly given future climate perturbations. 相似文献
/ The rural West of the United States is considered strongly antienvironment. The traditional economic reliance of the area on natural resources has long explained this antienvironment stance. The region consistently elects federal officials who as a group consistently vote against environmental bills and seek to undo existing federal environmental regulation. These politicians defend their antienvironment actions based on their perception of the economic composition and interests of the region. Recent studies, however, have suggested that rural residents are increasingly concerned about environmental issues. These studies, however, lack a consistent theoretical basis. This article uses an alternative economic typing system to examine the economic composition of rural Idaho and suggests that the results found using the alternative typing system might provide a theoretical basis to explain why some studies are finding increased rural environmental support. The results show that rural Idaho is much more economically diverse using this alternative typing methodology compared to the outcomes of traditional USDA economic methodologies. The policy and research implications of these findings are examined.KEY WORDS: Rural; Environmental policy; Economic composition 相似文献
Developmental relief has become the central doctrine of 'good practice' in humanitarian responses to complex political emergencies. This is despite the fact that a proliferation of such emergencies reflects a failure of development for people in those countries in crisis. Drawing on case study material from Sudan, Somalia, Rwanda and Uganda, this paper challenges assumptions made about the efficacy of developmental relief models in complex emergencies. The trend towards developmental relief practices coincides with an increasing acceptance of higher levels of humanitarian distress in Africa. Myths of aid dependency and the pursuit of sustainable programming in the midst of war are linked to a global reduction in aid. The mantra of 'local solutions to local problems' locates the causes of crises firmly within those societies in crisis. It provides a premise for international disengagement, and the denial of international responsibility for the genesis and prolongation of humanitarian crises in Africa. Assigning solutions to the poor, the marginalised and victimised through enhanced 'participation' and local financing of services sustains a myth that development is occurring, when in fact levels of distress are rising. 相似文献
Although dimethylsulfoniopropionate (DMSP) has a variety of functions in marine macroalgae including that of a cryoprotectant,
an osmolyte, a way to remove excess sulfur and energy, an antioxidant, and an allelopathic precursor, the latter two functions
are believed to be the most important in Ulva lactuca L. (=U. fenestrata) in intertidal populations on the coast of Washington state, USA. The present study found significant variation in DMSP concentrations
among U. lactuca collected in May 2005 from six sites ranging from 47°54.45′N (Possession Point, Whidbey Island, WA, USA) to 48°30.55′N (Shannon
Point Beach, Anacortes, WA, USA), and also among individuals within sites, and among tissues (basal tissues near the holdfast,
middle of the blades, and tips). Concentrations ranged from 37 to 224 μmol g−1 fresh mass (FM). In several 10-day experiments between July 2001 and August 2004 with U. lactuca collected from several places on the coast of Washington, the effects of nutrient level (DIN), light intensity and wavelength,
and grazing by the herbivorous gastropod Lacuna vincta, were examined. None of these manipulations resulted in DMSP concentrations that differed significantly from controls, and
variance in DMSP concentrations within each experiment was very low. Although DMSP concentrations in U. lactuca may be affected by factors not tested in these experiments, it is also possible that the observed spatial differences reflect
constitutive genotypic or phenotypic differences among geographically separated U. lactuca populations or among cryptic Ulva species.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
Competition among males to mate is generally associated with male-biased size dimorphism. In this study we examine mating behavior in the northern water snake (Nerodia sipedon), a species in which males are much smaller than females despite substantial competition among males to mate. Competition among males was a consequence of a male-biased operational sex ratio due to slightly higher female mortality from a birth sex ratio of 1 : 1, and, in 1 year, more synchronous and longer mating activity by males. Approximately one-third of both males and females appeared not to mate in a given year. Larger males were generally more likely to attempt mating, but size did not explain the variance in the number of aggregations in which individual males participated. Within aggregations, males that were successful at achieving intromission were larger than unsuccessful males in 1 of 2 years. Variation in condition (mass relative to length) and relative tail length were not generally useful predictors of either mating effort or success in males. Because large size was often advantageous to males, sexual size dimorphism appeared not to be a consequence of sexual selection favoring smaller males. Because sexual dimorphism was evident at birth, and both males and females matured sexually at about 4 years, sexual dimorphism was not simply a consequence of one sex growing at the maximum rate for longer. Female fecundity increased with size, and sex differences in size-fecundity relations may underly the pattern of sexual size dimorphism. However, because multiple mating by females is common, sperm competition is likely to be important in determining male reproductive success. Therefore, allocation of energy to sperm rather than growth may also prove to be an important influence on male growth rates and sexual size dimorphism. 相似文献
Southern elephant seals are important apex predators in a highly variable and unpredictable marine environment. In the presence
of resource limitation, foraging behaviours evolve to reduce intra-specific competition increasing a species’ overall probability
of successful foraging. We examined the diet of 141 (aged 1–3 years) juvenile southern elephant seals to test the hypotheses
that differences between ages, sexes and seasons in diet structure occur. We described prey species composition for common
squid and fish species and the mean size of cephalopod prey items for these age groups. Three cephalopod species dominated
the stomach samples, Alluroteuthis antarcticus, Histioteuthis eltaninae and Slosarczykovia circumantarcticus. We found age-related differences in both species composition and size of larger prey species that probably relate to ontogenetic
changes in diving ability and haul-out behaviour and prey availability. These changes in foraging behaviour and diet are hypothesised
to reduce intra-specific food competition concomitant with the increase in foraging niche of growing juveniles. 相似文献