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111.
Two species of salps, Salpa thompsoni and Ihlea racovitzai, were sampled during three cruises to the Lazarev Sea, Southern Ocean, in summer (December–January) 2005/2006, Autumn (April–May) 2004 and Winter (July–August) 2006. Dry weight, carbon, nitrogen, protein, lipid and carbohydrate contents were measured to characterize the potential value of salps as a food source for predators in the Antarctic ecosystem. Biochemical composition measurements showed that despite having a high percentage of water (~94% of wet weight), both species had relatively high carbon and protein contents in their remaining dry weight (DW). In particular I. racovitzai showed high carbon (up to 22% of DW) and protein (up to 32% of DW) values during all seasons sampled, compared to lower values for S. thompsoni (carbon content only about 15% of the DW, protein content about 10% of the DW). At the same time, carbohydrates (CH) and lipids (Lip) only accounted for a small portion of salp DW in both species (1.4% CH and 3.6% Lip for I. racovitzai; 2.1% CH and 2.9% Lip for S. thompsoni). There was little variability in the biochemical composition of either salp species between the seasons sampled. Both biochemical composition and life cycle characteristics suggest that Antarctic salps, especially I. racovitzai, may be important prey items for both cold and warm-blooded predators in an environment where food is often very scarce.  相似文献   
112.
Network theory is commonly used to reveal social interactions and the organisation of interconnected nodes—but has not yet been applied to animal invasions. Non-native species invasions are now considered one of the foremost threats to natural ecosystems and biodiversity. This is the first attempt to assess social network properties within a freshwater fish assemblage invaded by a non-native fish species. We show that invasive sunbleak Leucaspius delineatus is socially more strongly interconnected with native species than the native species with each other. The social networks also reveal characteristics of a ‘small world’ such as low clustering coefficients C and short path lengths L. The findings may indicate potential traits of successful invaders and the implication for the spread of pathogens between individuals within a group of animals that contain a non-native invasive species. The success of establishment and subsequent invasion may be highlighted not only by the capacity of the new species to adapt to the new environment, but also in its capacity to penetrate the social circle of the native community.  相似文献   
113.
Objective: The objective of this study was to investigate vehicle factors associated with child restraint tether use and misuse in pickup trucks and evaluate 4 labeling interventions designed to educate consumers on proper tether use.

Methods: Volunteer testing was performed with 24 subjects and 4 different pickup trucks. Each subject performed 8 child restraint installations among the 4 pickups using 2 forward-facing restraints: a Britax Marathon G4.1 and an Evenflo Triumph. Vehicles were selected to represent 4 different implementations of tether anchors among pickups: plastic loop routers (Chevrolet Silverado), webbing routers (Ram), back wall anchors (Nissan Frontier), and webbing routers plus metal anchors (Toyota Tundra). Interventions included a diagram label, Quick Response (QR) Code linked to video instruction, coordinating text label, and contrasting text tag.

Results: Subjects used the child restraint tether in 93% of trials. However, tether use was completely correct in only 9% of trials. An installation was considered functional if the subject attached the tether to a tether anchor and had a tight installation (ignoring routing and head restraint position); 28% of subjects achieved a functional installation. The most common installation error was attaching the tether hook to the anchor/router directly behind the child restraint (near the top of the seatback) rather than placing the tether through the router and attaching it to the anchor in the adjacent seating position. The Nissan Frontier, with the anchor located on the back wall of the cab, had the highest rate of correct installations but also had the highest rate of attaching the tether to components other than the tether anchor (seat adjustor, child restraint storage hook, around head restraint). None of the labeling interventions had a significant effect on correct installation; not a single subject scanned the QR Code to access the video instruction. Subjects with the most successful installations spent extensive time reviewing the vehicle manuals.

Conclusion: Current implementations of tether anchors among pickup trucks are not intuitive for child restraint installations, and alternate designs should be explored. Several different labeling interventions were ineffective at achieving correct tether use in pickup trucks.  相似文献   

114.
Calls for humanity to ‘reconnect to nature’ have grown increasingly louder from both scholars and civil society. Yet, there is relatively little coherence about what reconnecting to nature means, why it should happen and how it can be achieved. We present a conceptual framework to organise existing literature and direct future research on human–nature connections. Five types of connections to nature are identified: material, experiential, cognitive, emotional, and philosophical. These various types have been presented as causes, consequences, or treatments of social and environmental problems. From this conceptual base, we discuss how reconnecting people with nature can function as a treatment for the global environmental crisis. Adopting a social–ecological systems perspective, we draw upon the emerging concept of ‘leverage points’—places in complex systems to intervene to generate change—and explore examples of how actions to reconnect people with nature can help transform society towards sustainability.  相似文献   
115.
Unusually cold winters, a slowing in upward global temperatures, or an increase in Arctic sea ice extent are often falsely cast as here-and-now disconfirmation of the scientific consensus on climate change. Such conclusions are examples of “end point bias,” the well documented psychological tendency to interpret a recent short-term fluctuation as a reversal of a long-term trend. End point bias poses a challenge to those trying to communicate cross-decade climate warming trends. In this study, we demonstrate that exposure to misleading scientific information on FoxNews.com that evokes end point bias can affect the beliefs of liberals and moderates as well as conservatives. We also show that the leveraging-involving-visualizing-analogizing communication model can reduce the effects of endpoint bias among moderates and liberals at the same time as it dampens both the ideological and endpoint biasing of conservatives.  相似文献   
116.
In this article we examine in real time the political selective exposure process involved when the public confronted the “walrus haul out” of October 2014, a news event attributed by some climate change researchers to the effects of the climate change-driven reduction of Arctic sea ice. Analyzing data assessing the amount of major TV and cable news network coverage of the haul out, and evaluating public opinion data collected from a rolling cross-sectional survey of US adults take at the time, we show that coverage of this event was not equitably distributed across news media news sources, that exposure to news source is related to the respondents’ ideological dispositions, and that exposure to coverage of the walrus haul out is related to ideology, the selectivity of political news habits, and climate change knowledge. We conclude with a discussion of the apparent inevitability of selective exposure to media coverage of climate change-related events and the implications for effective climate change communication.  相似文献   
117.
Decades of research studies demonstrate links between healthy environment, healthy lifestyles, and healthy people. This study evaluated the correlations between young adult conservation workers' perceived stress, personal effectiveness, and nature experience using quantitative and qualitative social science methods. The study cohort numbered nearly 300 individuals serving on small crews for an entire year, and were dispersed across Washington State (USA) to participate in conservation projects in rural to urban landscapes. Pre- and post-test surveys, using validated measures of perceived stress, health dimensions, and personal resiliency, were further informed by mid-year, field-based interviews. Overall, the young adults expressed fatigue with the physical work but were quite healthy when compared to national benchmarks. They indicated a reduction in perceived stress, and indicated social function influences based on the conservation work. Conclusions address the importance and implications of expanding this work opportunity to a more diverse cohort and future research needs.  相似文献   
118.
Semipermeable membrane devices (SPMDs) were deployed at eight sites within the Buffalo Slough, near Portland, Oregon, to (1) measure the spatial and seasonal distribution of dissolved polycyclic aromatic hydrocarbon (PAH) and organochlorine (OC) compounds in the slough, (2) assess the usefulness of SPMDs as a tool for investigating and monitoring hydrophobic compounds throughout the Columbia Slough system, and (3) evaluate the utility of SPMDs as a tool for measuring the long-term effects of watershed improvement activities. Data from the SPMDs revealed clear spatial and seasonal differences in water quality within the slough and indicate that for hydrophobic compounds, this time-integrated passive-sampling technique is a useful tool for long-term watershed monitoring. In addition, the data suggest that a spiking rate of 2–5 μg/SPMD of permeability/performance reference compounds, including at least one compound that is not susceptible to photodegradation, may be optimum for the conditions encountered here.  相似文献   
119.
Climate change, overfishing, and other anthropogenic drivers are forcing marine resource users and decision makers to adapt—often rapidly. In this article we introduce the concept of pathways to rapid adaptation to crisis events to bring attention to the double-edged role that institutions play in simultaneously enabling and constraining swift responses to emerging crises. To develop this concept, we draw on empirical evidence from a case study of the iconic Maine lobster (Homarus americanus) industry. In the Gulf of Maine, the availability of Atlantic herring (Clupea harengus) stock, a key source of bait in the Maine lobster industry, declined sharply. We investigate the patterns of bait use in the fishery over an 18-year period (2002–2019) and how the lobster industry was able to abruptly adapt to the decline of locally-sourced herring in 2019 that came to be called the bait crisis. We found that adaptation strategies to the crisis were diverse, largely uncoordinated, and imperfectly aligned, but ultimately led to a system-level shift towards a more diverse and globalized bait supply. This shift was enabled by existing institutions and hastened an evolution in the bait system that was already underway, as opposed to leading to system transformation. We suggest that further attention to raceways may be useful in understanding how and, in particular, why marine resource users and coastal communities adapt in particular ways in the face of shocks and crises.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01617-8.  相似文献   
120.
A number of models have been developed to explain nurses' turnover behavior. The common theme that emerges from these models is that turnover behavior is a multistage process that includes attitudinal, decisional, and behavioral components. The purpose of this study was to assess both the direct and indirect impact of certain pay policies upon the turnover intentions of paediatric nurses. The two major questions addressed were: What was the relative impact of job satisfaction, pay satisfaction, and organizational commitment upon the turnover intentions of paediatric nurses eligible for these pay policies? What model accurately portrays the relationship among these three independent variables and turnover intentions? Exploration of the causal pathways among these variables and demographic factors revealed complex models of association. The results suggest that job satisfaction has only an indirect influence on the intention to quit, whereas organizational commitment has the strongest and most direct impact. A further finding that pay satisfaction had both direct and indirect effects on turnover intent was consistent with administrators' assumptions underlying the pay policies. Control variables such as having a degree, having children, and working 12-hour shifts were found to have both direct and indirect influences upon pay satisfaction and turnover intent. © 1998 John Wiley & Sons, Ltd.  相似文献   
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