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11.
This study meta‐analyzed the relationships between locus of control (LOC) and a wide range of work outcomes. We categorized these outcomes according to three theoretical perspectives: LOC and well‐being, LOC and motivation, and LOC and behavioral orientation. Hypotheses reflecting these three perspectives were proposed and tested. It was found that internal locus was positively associated with favorable work outcomes, such as positive task and social experiences, and greater job motivation. Our findings are discussed in relation to research on core self‐evaluation and the Big Five personality traits. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
12.
ABSTRACT

Sketch-map-facilitated interviews were conducted in 23 villages in two adjacent regions in the southern Yucatan Peninsula of Mexico – the Maya (and increasingly Mennonite) forest-agriculture mosaic of the Chenes, and the late-20th-century-settlement forest frontier of Calakmul – to determine the frequency and typology of local-scale reserves, including the external (e.g. Payments for Environmental Services programs) and internal sources of their generation. 9% of the study communities are found to satisfy the author’s criteria for deliberate, autochthonous reserves. The static polygon reserve and static map are found to have limited value for understanding the evolving cultural ecologies of these regions. Alternative approaches are discussed, particularly those employed by geographers.  相似文献   
13.
Large, intact areas of tropical peatland are highly threatened at a global scale by the expansion of commercial agriculture and other forms of economic development. Conserving peatlands on a landscape scale, with their hydrology intact, is of international conservation importance to preserve their distinctive biodiversity and ecosystem services and maintain their resilience to future environmental change. We explored threats to and opportunities for conserving remaining intact tropical peatlands; thus, we excluded peatlands of Indonesia and Malaysia, where extensive deforestation, drainage, and conversion to plantations means conservation in this region can protect only small fragments of the original ecosystem. We focused on a case study, the Pastaza‐Marañón Foreland Basin (PMFB) in Peru, which is among the largest known intact tropical peatland landscapes in the world and is representative of peatland vulnerability. Maintenance of the hydrological conditions critical for carbon storage and ecosystem function of peatlands is, in the PMFB, primarily threatened by expansion of commercial agriculture linked to new transport infrastructure that is facilitating access to remote areas. There remain opportunities in the PMFB and elsewhere to develop alternative, more sustainable land‐use practices. Although some of the peatlands in the PMFB fall within existing legally protected areas, this protection does not include the most carbon‐dense (domed pole forest) areas. New carbon‐based conservation instruments (e.g., REDD+, Green Climate Fund), developing markets for sustainable peatland products, transferring land title to local communities, and expanding protected areas offer pathways to increased protection for intact tropical peatlands in Amazonia and elsewhere, such as those in New Guinea and Central Africa which remain, for the moment, broadly beyond the frontier of commercial development.  相似文献   
14.
The purpose of this study was to validate the use of adenosine triphosphate (ATP) for evaluating hygiene intervention effectiveness in reducing viral dissemination in an office environment. The bacterial virus MS-2 was used to evaluate two scenarios, one where the hand of an individual was contaminated and another where a fomite was contaminated. MS-2 was selected as a model because its shape and size are similar to many human pathogenic viruses. Two separate experiments were conducted, one in which the entrance door push plate was inoculated and the other in which the hand of one selected employee was inoculated. In both scenarios, 54 selected surfaces in the office were tested to assess the dissemination of the virus within the office. Associated surface contamination was also measured employing an ATP meter. More than half of the tested hands and surfaces in the office were contaminated with MS-2 within 4 h. Next, an intervention was conducted, and each scenario was repeated. Half of the participating employees were provided hand sanitizer, facial tissues, and disinfecting wipes, and were instructed in their use. A significant (p < 0.05) reduction was observed in the number of surfaces contaminated with virus. This reduction in viral spread was evident from the results of both viral culture and the surface ATP measurements, although there was no direct correlation between ATP measurements with respect to viral concentration. Although ATP does not measure viruses, these results demonstrate that ATP measurements could be useful for evaluating the effectiveness of hygiene interventions aimed at preventing viral spread in the workplace.  相似文献   
15.
The 137Cs activity of salt marsh and tidal flat sediments of the northern part of the European Wadden Sea was studied based on a comprehensive dataset of 210Pb dated cores. The 137Cs inventory of salt marsh sediments shows a major peak corresponding to the Chernobyl accident in 1986, and a minor peak located in the late 1960s interpreted as the combined effect of atmospheric testing of nuclear weapons. Emissions from the nuclear reprocessing plant Sellafield are not reflected as peaks in 137Cs activity, but may contribute to the rising 137Cs activity in the years prior to 1986. The 137Cs activity of tidal flat sediments differs from salt marsh sediment in two respects. First, the activity is much lower and, second, the major peak in the 1980s is located in the beginning instead of in the middle of the decade. The differences in 137Cs inventory between the two environments are interpreted to result from repeated cycles of deposition/resuspension and mixing on tidal flats. A simple model illustrating the consequence of mixings returns an apparent shift of major peaks in 137Cs activities backwards in time corresponding to the mixing depth divided by the deposition rate.  相似文献   
16.
Because catchment characteristics determine sediment and nutrient inputs to streams, upland disturbance can affect stream chemistry. Catchments at the Fort Benning Military Installation (near Columbus, Georgia) experience a range of upland disturbance intensities due to spatial variability in the intensity of military training. We used this disturbance gradient to investigate the effects of upland soil and vegetation disturbance on stream chemistry. During baseflow, mean total suspended sediment (TSS) concentration and mean inorganic suspended sediment (ISS) concentration increased with catchment disturbance intensity (TSS: R2= 0.7, p = 0.005, range = 4.0-10.1 mg L(-1); ISS: R2= 0.71, p = 0.004, range = 2.04-7.3 mg L(-1)); dissolved organic carbon (DOC) concentration (R2= 0.79, p = 0.001, range = 1.5-4.1 mg L(-1)) and soluble reactive phosphorus (SRP) concentration (R2= 0.75, p = 0.008, range = 1.9-6.2 microg L(-1)) decreased with increasing disturbance intensity; and ammonia (NH4+), nitrate (NO3-), and dissolved inorganic nitrogen (DIN) concentrations were unrelated to disturbance intensity. The increase in TSS and ISS during storms was positively correlated with disturbance (R2= 0.78 and 0.78, p = 0.01 and 0.01, respectively); mean maximum change in SRP during storms increased with disturbance (r = 0.7, p = 0.04); and mean maximum change in NO3- during storms was marginally correlated with disturbance (r = 0.58, p = 0.06). Soil characteristics were significant predictors of baseflow DOC, SRP, and Ca2+, but were not correlated with suspended sediment fractions, any nitrogen species, or pH. Despite the largely intact riparian zones of these headwater streams, upland soil and vegetation disturbances had clear effects on stream chemistry during baseflow and stormflow conditions.  相似文献   
17.
We assessed the extent to which constituents of PM2.5 (transition metals, sodium, chloride) contribute to the ability to generate hydroxyl radicals (OH) in vitro in PM2.5 sampled at 20 locations in 19 European centres participating in the European Community Respiratory Health Survey. PM2.5 samples (n = 716) were collected on filters over one year and the oxidative activity of particle suspensions obtained from these filters was then assessed by measuring their ability to generate OH in the presence of hydrogen peroxide. Associations between OH formation and the studied PM constituents were heterogeneous. The total explained variance ranged from 85% in Norwich to only 6% in Albacete. Among the 20 centres, 15 showed positive correlations between one or more of the measured transition metals (copper, iron, manganese, lead, vanadium and titanium) and OH formation. In 9 of 20 centres OH formation was negatively associated with chloride, and in 3 centres with sodium. Across 19 European cities, elements which explained the largest variations in OH formation were chloride, iron and sodium.  相似文献   
18.
Montane Meadows as Indicators of Environmental Change   总被引:1,自引:0,他引:1  
We used a time series of satellite multispectral imagery for mapping and monitoring six classes of montane meadows arrayed along a moisture gradient (from hydric to mesic to xeric). We hypothesized that mesic meadows would support the highest species diversity of plants, birds, and butterflies because they are more moderate environments. We also hypothesized that mesic meadows would exhibit the greatest seasonal and interannual variability in spectral response across years. Field sampling in each of the meadow types was conducted for plants, birds, and butterflies in 1997 and 1998. Mesic meadows supported the highest plant species diversity, but there was no significant difference in bird or butterfly species diversity among meadow types. These data show that it may be easier to detect significant differences in more species rich taxa (e.g., plants) than taxa that are represented by fewer species (e.g., butterflies and birds). Mesic meadows also showed the greatest seasonal and interannual variability in spectral response. Given the rich biodiversity of mesic montane meadows and their sensitivity to variations in temperature and moisture, they may be important to monitor in the context of environmental change  相似文献   
19.

Problem

Between 1992 and 2005, 1412 workers on farms died from tractor overturns. A Rollover Protective Structure (ROPS) is a proven intervention to reduce overturn deaths. However, farm characteristics that are associated with the adoption of ROPS are not well understood.

Methods

ROPS prevalence statistics were derived from National Institute for Occupational Safety and Health (NIOSH) surveys that tracked ROPS use on farms. Data were from the years 1993, 2001, and 2004.

Results

In 1993, 38% of tractors were equipped with ROPS. This increased to 51% by 2004. ROPS prevalence rates were higher on farms in the Southern region of the United States, on farms where the operator was 25-34 years old, and on farms with $100,000 or more of farm sales. Low ROPS prevalence rates were associated with farm operators 65 years old or older and with farms with less than $10,000 of farm product sales.

Summary

The increase in ROPS prevalence between 1993 and 2004 has not been sufficient to decrease the rate of tractor overturn deaths on farms. Incentive programs targeting older farm operators and low-income farm operations are suggested to increase ROPS use on tractors.

Impact on Industry

The study provides farm characteristics associated with low ROPS prevalence rates. The results can be used to target farms for future ROPS promotion activities.  相似文献   
20.
PROBLEM: Federal policy recommends environmental strategies as part of a comprehensive workplace violence program in healthcare and social services. The purpose of this project was to contribute specific, evidence-based guidance to the healthcare and social services employer communities regarding the use of environmental design to prevent violence. METHOD: A retrospective record review was conducted of environmental evaluations that were performed by an architect in two Participatory Action Research (PAR) projects for workplace violence prevention in 2000 and, in the second project in 2005. Ten facility environmental evaluation reports along with staff focus group reports from these facilities were analyzed to categorize environmental risk factors for Type II workplace violence. RESULTS: Findings were grouped according to their impact on access control, the ability to observe patients (natural surveillance), patient and worker safety (territoriality), and activity support. DISCUSSION: The environmental assessment findings reveal design and security issues that, if corrected, would improve safety and security of staff, patients, and visitors and reduce fear and unpredictability. IMPACT ON INDUSTRY: Healthcare and social assistance employers can improve the effectiveness of violence prevention efforts by including an environmental assessment with complementary hazard controls.  相似文献   
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