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91.
The desert tortoise (Gopherus agassizii) is federally listed as "threatened" and is afforded protection in several U.S. states including California, Nevada, Utah, and Arizona. Numerous factors ranging from habitat destruction to disease are thought to contribute to the species' decline throughout its range. Data collection on desert tortoises in the wild is challenging because tortoises are secretive, and many age and size classes are virtually undetectable in the wild. Detection dogs have been used for decades to assist humans, and the use of dogs for wildlife surveys is of increasing interest to scientists and wildlife managers. To address the basic question of whether dogs could be used to survey for the desert tortoise, we quantified the reliability and efficacy of dogs trained for this purpose. Efficacy is the number of tortoises that dogs find out of a known population. Reliability is a measure of how many times a dog performs its trained alert when it has found a tortoise. A series of experimental trials were designed to statistically quantify these metrics in the field setting where dogs trained to locate live desert tortoises were tested on their ability to find them on the surface, in burrows, and in mark-recapture surveys. Results indicated that dogs are effective at and can safely locate desert tortoises with reliability on the surface and are capable of detecting tortoises in burrows under a range of environmental conditions. Dogs found tortoises at the same statistical rate at temperatures between 12 degrees and 27 degrees C, relative humidity from 16% to 87%, and wind speeds up to 8 m/s. In both surface and burrow trials, dogs found >90% of the experimental animals. In comparative studies with humans, dogs found tortoises as small as 30 mm, whereas the smallest tortoise located by human survey teams was 110 mm. Although not all dogs or dog teams meet the requirements to conduct wildlife surveys, results from this study show the promise in using dogs to increase our knowledge of rare, threatened, and endangered species through improved data collection methods.  相似文献   
92.
In order to improve our understanding of the nature, measurement and prediction of salts of perfluorooctanoic acid (PFOA) in air, two studies were performed along the fence line of a fluoropolymer manufacturing facility. First, a six-event, 24-hr monitoring series was performed around the fence line using the OSHA versatile sampler (OVS) system. Perfluorooctanoate concentrations were determined as perfluorooctanoic acid (PFOA) via liquid chromatography and mass spectrometry. Those data indicated that the majority of the PFOA was present as a particulate. No vapor-phase PFOA was detected above a detection limit of approximately 0.07 microg/m3. A follow-up study using a high-volume cascade impactor verified the range of concentrations observed in the OVS data. Both studies aligned with the major transport direction and range of concentrations predicted by an air dispersion model, demonstrating that model predictions agreed with monitoring results. Results from both monitoring methods and predictions from air dispersion modeling showed the primary direction of transport for PFOA was in the prevailing wind direction. The PFOA concentration measured at the site fence over the 10-week sampling period ranged from 0.12 to 0.9 microg/m3. Modeled predictions for the same time period ranged from 0.12 to 3.84 microg/m3. Less than 6% of the particles were larger than 4 microm in size, while almost 60% of the particles were below 0.3 microm. These studies are believed to be the first published ambient air data for PFOA in the environment surrounding a manufacturing facility.  相似文献   
93.
Controlling invasive species is critical for conservation but can have unintended consequences for native species and divert resources away from other efforts. This dilemma occurs on a grand scale in the North American Great Lakes, where dams and culverts block tributary access to habitat of desirable fish species and are a lynchpin of long‐standing efforts to limit ecological damage inflicted by the invasive, parasitic sea lamprey (Petromyzon marinus). Habitat restoration and sea‐lamprey control create conflicting goals for managing aging infrastructure. We used optimization to minimize opportunity costs of habitat gains for 37 desirable migratory fishes that arose from restricting sea lamprey access (0–25% increase) when selecting barriers for removal under a limited budget (US$1–105 million). Imposing limits on sea lamprey habitat reduced gains in tributary access for desirable species by 15–50% relative to an unconstrained scenario. Additional investment to offset the effect of limiting sea‐lamprey access resulted in high opportunity costs for 30 of 37 species (e.g., an additional US$20–80 million for lake sturgeon [Acipenser fulvescens]) and often required ≥5% increase in sea‐lamprey access to identify barrier‐removal solutions adhering to the budget and limiting access. Narrowly distributed species exhibited the highest opportunity costs but benefited more at less cost when small increases in sea‐lamprey access were allowed. Our results illustrate the value of optimization in limiting opportunity costs when balancing invasion control against restoration benefits for diverse desirable species. Such trade‐off analyses are essential to the restoration of connectivity within fragmented rivers without unleashing invaders.  相似文献   
94.
Objectives: In this study, we sought to accomplish the following objectives: to (1) calculate the percentage of children considered appropriately restrained across 8 criteria of increasing restrictiveness; (2) examine agreement between age- and size-based appropriateness criteria; (3) assess for changes in the percentage of children considered appropriately restrained by the 8 criteria between 2011 (shortly after updates to U.S. guidelines) and 2015.

Methods: Data from 2 cross-sectional surveys of 928 parents of children younger than 12 years old (n = 591 in 2011, n = 337 in 2015) were analyzed in 2017. Child age, weight, and height were measured at an emergency department visit and used to determine whether the parent-reported child passenger restraint was considered appropriate according to 8 criteria. Age-based criteria were derived from Michigan law and U.S. guidelines. Weight, height, and size-based criteria were derived from typical restraints available in the United States in 2007 and 2011. The percentage appropriate restraint use was calculated for each criterion. The kappa statistic was used to measure agreement between criteria. Change in appropriateness from 2011 to 2015 was assessed with chi-square statistics.

Results: Percentage appropriate restraint use varied from a low of 19% for higher weight limits in 2011 to a high of 91% for Michigan law in 2015. Agreement between criteria was slight to moderate. The lowest kappa was for Michigan law and higher weight limits in 2011 (κ = 0.06) and highest for U.S. guidelines and lower weight limits in 2011 (κ = 0.60). Percentage appropriate restraint use was higher in 2015 than 2011 for the following criteria: U.S. guidelines (74 vs. 58%, P < .001), lower weight (57 vs. 47%, P = .005), higher weight (25 vs. 19%, P = .03), greater height (39 vs. 26%, P < .001), and greater size (42 vs. 30%, P = .001).

Conclusions: The percentage of children considered to be using an appropriate restraint varied substantially across criteria. Aligning the definition of appropriate restraint use with current U.S. guidelines would increase consistency in reporting results from studies of child passenger safety in the United States. Potential explanations for the increased percentage of children considered appropriately restrained between 2011 and 2015 include adoption of the updated U.S. guidelines and the use of child passenger restraints with higher weight and height limits.  相似文献   
95.
Pollinator welfare is a recognized research and policy target, and urban greenspaces have been identified as important habitats. Yet, landscape-scale habitat fragmentation and greenspace management practices may limit a city's conservation potential. We examined how landscape configuration, composition, and local patch quality influenced insect nesting success across inner-city Cleveland, Ohio (U.S.A.), a postindustrial legacy city containing a high abundance of vacant land (over 1600 ha). Here, 40 vacant lots were assigned 1 of 5 habitat treatments (T1, vacant lot; T2, grass lawn; T3, flowering lawn; T4, grass prairie; and T5, flowering prairie), and we evaluated how seeded vegetation, greenspace size, and landscape connectivity influenced cavity-nesting bee and wasp reproduction. Native bee and wasp larvae were more abundant in landscapes that contained a large patch (i.e., >6 ha) of contiguous greenspace, in habitats with low plant biomass, and in vacant lots seeded with a native wildflower seed mix or with fine-fescue grass, suggesting that fitness was influenced by urban landscape features and habitat management. Our results can guide urban planning by demonstrating that actions that maintain large contiguous greenspace in the landscape and establish native plants would support the conservation of bees and wasps. Moreover, our study highlights that the world's estimated 350 legacy cities are promising urban conservation targets due to their high abundance of vacant greenspace that could accommodate taxa's habitat needs in urban areas.  相似文献   
96.
Objective: This study evaluated the effectiveness of a series of 1-year multifaceted school-based programs aimed at increasing booster seat use among urban children 4–7 years of age in economically disadvantaged areas.

Methods: During 4 consecutive school years, 2011–2015, the Give Kids a Boost (GKB) program was implemented in a total of 8 schools with similar demographics in Dallas County. Observational surveys were conducted at project schools before project implementation (P0), 1–4 weeks after the completion of project implementation (P1), and 4–5 months later (P2). Changes in booster seat use for the 3 time periods were compared for the 8 project and 14 comparison schools that received no intervention using a nonrandomized trial process.

The intervention included (1) train-the-trainer sessions with teachers and parents; (2) presentations about booster seat safety; (3) tailored communication to parents; (4) distribution of fact sheets/resources; (5) walk-around education; and (6) booster seat inspections.

The association between the GKB intervention and proper booster seat use was determined initially using univariate analysis. The association was also estimated using a generalized linear mixed model predicting a binomial outcome (booster seat use) for those aged 4 to 7 years, adjusted for child-level variables (age, sex, race/ethnicity) and car-level variables (vehicle type). The model incorporated the effects of clustering by site and by collection date to account for the possibility of repeated sampling.

Results: In the 8 project schools, booster seat use for children 4–7 years of age increased an average of 20.9 percentage points between P0 and P1 (P0 = 4.8%, P1 = 25.7%; odds ratio [OR] = 6.9; 95% confidence interval [CI], 5.5, 8.7; P < .001) and remained at that level in the P2 time period (P2 = 25.7%; P < .001, for P0 vs. P2) in the univariate analysis. The 14 comparison schools had minimal change in booster seat use. The multivariable model showed that children at the project schools were significantly more likely to be properly restrained in a booster seat after the intervention (OR = 2.7; 95% CI, 2.2, 3.3) compared to the P0 time period and compared to the comparison schools.

Conclusion: Despite study limitations, the GKB program was positively associated with an increase in proper booster seat use for children 4–7 years of age in school settings among diverse populations in economically disadvantaged areas. These increases persisted into the following school year in a majority of the project schools. The GKB model may be a replicable strategy to increase booster seat use among school-age children in similar urban settings.  相似文献   

97.
We utilize social learning theory to test the role‐modeling effect of supervisor expediency (i.e., a supervisor's use of unethical practices to expedite work for self‐serving purposes). In particular, we examine the relationship between supervisor expediency and employee expediency, as moderated by leader–member exchange (LMX) and mediated by employee unethical tolerance. We predict that employees are more likely to model their supervisors' expedient behaviors when their relationship is characterized by high‐LMX (a high‐quality exchange relationship that is rich in socioemotional support). Furthermore, we argue that supervisor expediency, especially when LMX is high, influences employees' attitudes of unethical tolerance, which then affects employees' expedient behaviors. Across 2 multisource field studies and a third time‐lagged field study, we found general support for our theoretical predictions. Theoretical and practical implications are discussed.  相似文献   
98.
By discussing “families” of moral emotions, we synthesize and review the moral emotions literature in an effort to advance organizational scholarship. First, we broadly discuss “what constitutes a moral emotion?” Second, we critically examine each family of moral emotions. We discuss key controversies and debates, particularly in terms of construct overlap, and provide recommendations. Third, we review scholarly work on each family of moral emotions in the workplace and offer ideas for future research. Finally, in our general future directions, we discuss a range of theoretical perspectives that can be used to advance the moral emotions literature in the management field.  相似文献   
99.
100.
Epidemiological research underlying US air quality regulations documents significant associations between measures of fine particles and premature mortality. Recent studies examine potential mechanistic pathways, related to heart and lung functioning, that may contribute to the observed deaths. Our results support these pathophysiological analyses. We examine whether the onset of serious health conditions, consistent with disease pathways, is related to current and long-term exposure to particulate matter and ozone. Associations between air pollution and alternative indicators of health status are also evaluated. The 1996 wave of the Health and Retirement Study is used with a two-step estimator acknowledging limitations in our ability to measure individual exposures. The findings suggest significant current and long-term effects of particulates on new cases of heart attacks and angina, reinforcing the disease pathways identified in epidemiological studies. Long-term air pollution exposure is also a determinant of recently diagnosed chronic lung conditions and reports of shortness of breath.  相似文献   
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