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211.
Birth dates from almost 3 million babies born between 1969 and 2005 in Switzerland were analyzed for the weekday of birth. As in other countries but with unprecedented amplitude, a very marked non-random distribution was discovered with decreasing numbers of births on weekends, reaching -17.9% in 2005. While most of this weekend births avoidance rate is due to fewer births on Sundays (up to -21.7%), the downward trend is primarily a consequence of decreasing births on Saturdays (up to -14.5%). For 2005, these percentages mean that 3,728 fewer babies are born during weekends than could be expected from equal distribution. Most interestingly and surprisingly, weekend birth-avoiding rates are significantly correlated with birth numbers (r = 0.86), i.e. the lower the birth number per year, the lower the number of weekend births. The increasing avoidance of births during weekends is discussed as being a consequence of increasing numbers of caesarean sections and elective labor induction, which in Switzerland reach 29.2 and 20.5%, respectively, in 2004. This hypothesis is supported by the observation that both primary and secondary caesarean sections are significantly correlated with weekend birth avoidance rates. It is therefore likely that financial aspects of hospitals are a factor determining the avoidance of weekend births by increasing the numbers of caesarean sections. 相似文献
212.
Sarah Michaels 《Environmental Science & Policy》2009,12(7):994-1011
The benefits of utilizing intermediaries to broker understanding between environmental scientists and policy makers have become widely touted. Yet little is known about the tasks boundary spanners undertake to develop environmental policy solutions and how these tasks fit into frameworks intended to advance public policy decision making. Such frameworks may be constructed to aid decision makers in differentiating between the types of environmental policy issues that confront them or the policy settings in which they are operating. Consequently, this paper examines how six different knowledge brokering strategies; informing, consulting, matchmaking, engaging, collaborating and building capacity might be employed in responding to different types of environmental policy problems or policy settings identified in decision aiding frameworks. Using real world examples, four frameworks are reviewed. They are; Lindquist's [Lindquist, E.A., 1988. What do decision models tell us about information use? Knowledge in Society 1 (2), 86–111; Lindquist, E.A., 1990. The third community, policy inquiry, and social scientists. In: Stephen Brooks, S., Gagnon, A. (Eds.), Social Scientists, Policy and the State. Praeger, New York; Lindquist, E.A., 2001. Discerning policy influence: framework for a strategic evaluation of IDRC-Supported research] decision regimes, Turnhout et al.’s [Turnhout, E., Hisschemoller, M., Eijsackers, H., 2007. Ecological indicators: between the two fires of science and policy. Ecological Indicators 7 (2), 215–228] science policy typology, Holling's [Holling, C.S., 1995. What barriers? What bridges? In: Gunderson, L.H., Holling, C.S. (Eds.), Barriers and Bridges to the Renewal of Ecosystems and Institutions. Columbia University Press, New York, pp. 3–34] adaptive cycle and Kurtz and Snowden's [Kurtz, C.F., Snowden, D.J., 2003. The new dynamics of strategy: sense-making in a complex and complicated world. IBM Systems Journal 42 (3), 462–483] Cynefin domains. For the different problem types or policy settings described in the decision aiding frameworks primary knowledge brokering strategies are identified. While the frameworks differ in their conceptual constructions, the applicability of specific knowledge brokering strategies serve as a commonality across particular problem types and policy settings. 相似文献
213.
Chad Staddon Sarah Ward Laura De Vito Adriana Zuniga-Teran Andrea K. Gerlak Yolandi Schoeman Aimee Hart Giles Booth 《The Environmentalist》2018,38(3):330-338
After briefly reviewing key resilience engineering perspectives and summarising some green infrastructure (GI) tools, we present the contributions that GI can make to enhancing urban resilience and maintaining critical system functionality across complex integrated social–ecological and technical systems. We then examine five key challenges for the effective implementation of GI that include (1) standards; (2) regulation; (3) socio-economic factors; (4) financeability; and (5) innovation. We highlight ways in which these challenges are being dealt with around the world, particularly through the use of approaches that are both context appropriate and socially inclusive. Although progress surmounting these challenges has been made, more needs to be done to ensure that GI approaches are inclusive and appropriate and feature equally alongside more traditional ‘grey’ infrastructure in the future of urban resilience planning. This research was undertaken for the Resilience Shift initiative to shift the approach to resilience in practice for critical infrastructure sectors. The programme aims to help practitioners involved in critical infrastructure to make decisions differently, contributing to a safer and better world. 相似文献
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215.
Sarah M. Elliott Richard L. Kiesling Zachary G. Jorgenson Daniel C. Rearick Heiko L. Schoenfuss Kim T. Fredricks Mark P. Gaikowski 《Journal of the American Water Resources Association》2014,50(2):376-387
Developmental and reproductive effects of 17β‐estradiol (E2) exposure on two generations of fathead minnows and one generation of bluegill sunfish were assessed. Fish were exposed to E2 for six continuous weeks in outdoor mesocosms simulating natural lake environments. First generation fish were exposed while sexually mature. Second generation fathead minnows were exposed either during early development, sexual maturity, or both stages. Multiple endpoints were measured to assess effects of E2 exposure on fecundity and fish health and development. Plasma vitellogenin concentrations were highly variable in all fish. Differences in egg production timing for both species indicate differences in fecundity between females exposed to E2 and controls. First generation fathead minnows exposed to E2 had lower body condition factors and reduced secondary sexual characteristic expression by males. Only a difference in relative liver weight was observed in second generation fathead minnows. First generation bluegill males exposed to E2 had significantly smaller testes compared to controls. Although fish response was highly variable, results indicate that exposure to E2 at environmentally relevant concentrations affect fathead minnow and bluegill sunfish health and development, which may have implications for the health and sustainability of fish populations. Furthermore, exposure timing and environmental factors affect fish response to E2 exposure. 相似文献
216.
Sarah E. Fredericks 《国际发展与全球生态学杂志》2013,20(6):490-499
At least since the Brundtland Report, technical assessments of what can be sustained and values about what is desirable to sustain, for whom, and for how long have been intertwined. This intersection is particularly evident in the assumption that justice among people living today and between present and future generations is a key part of sustainability. In official international policy documents and academic studies of sustainability, this justice may include the equitable distribution of environmental benefits and burdens, distributive justice, or the ability of people to meaningfully contribute to decisions that affect their lives, participatory justice. Yet, the process of developing indicators and indexes to track movement toward or away from sustainability has been dominated by technical, economic, and environmental assessments. This raises questions about whether or not indexes align with and thus will monitor and encourage progress toward sustainability in a technically possible and desirable way. To begin to answer this question, this paper identifies definitions of justice used in sustainability discourse and evaluates the degree to which sustainability indicators and indexes align with these concepts. The 2010 Environmental Performance Index, Eurostat's Sustainable Development Indicators, and a group of local indicators and indexes are examined. It is found that the indicators embody various aspects of justice, though they are still significantly limited by the available data, especially as they generally cannot monitor inequities between subpopulations and have a limited capacity to monitor progress toward participatory justice. 相似文献
217.
Jellyfish accumulations are often problematic for tourism and fisheries both along European coastlines and overseas. They damage the reputation of several seaside resorts and cause serious economic losses. On the German Baltic coast, jellyfish accumulations are well known, too. Besides population increase due to anthropogenic effects, normal hydrodynamic processes are notable key factors when it comes to jellyfish accumulations. Along German Baltic coastlines, moon jellyfish (Aurelia aurita) occur most frequently but also stinging lion??s mane jellyfish (Cyanea capillata) appear regularly, however not as abundant. The objectives of our study were a) to screen when, where, how many and which jellyfish species occur on German Baltic coasts, b) to find the causes for jellyfish accumulations and c) to evaluate how beach visitors perceive native medusae and whether information can influence their perception. Different methods where combined: systematic jellyfish observations in cooperation with lifeguards, investigations of jellyfish abundance in shallow water zones, and interviews with beach visitors. Our results suggest that jellyfish occurrence along the German Baltic coast correlates with offshore wind or shore-parallel wind, which cause upwelling events. In contrast, there is no evidence that frequency of jellyfish occurrence was dependent on water temperature in summer. In regard to tourism, we found that beach visitors who received information about jellyfish stated to feel significantly less bothered by medusae. Overall, this article addresses different methods to learn more about jellyfish accumulations and it shows information strategies in terms of improved beach management. 相似文献
218.
Parasite transmission in complex communities: predators and alternative hosts alter pathogenic infections in amphibians 总被引:1,自引:0,他引:1
While often studied in isolation, host-parasite interactions are typically embedded within complex communities. Other community members, including predators and alternative hosts, can therefore alter parasite transmission (e.g., the dilution effect), yet few studies have experimentally evaluated more than one such mechanism. Here, we used data from natural wetlands to design experiments investigating how alternative hosts and predators of parasites mediate trematode (Ribeiroia ondatrae) infection in a focal amphibian host (Pseudacris regilla). In short-term predation bioassays involving mollusks, zooplankton, fish, larval insects, or newts, four of seven tested species removed 62-93% of infectious stages. In transmission experiments, damselfly nymphs (predators) and newt larvae (alternative hosts) reduced infection in P. regilla tadpoles by -50%, whereas mosquitofish (potential predators and alternative hosts) did not significantly influence transmission. Additional bioassays indicated that predators consumed parasites even in the presence of alternative prey. In natural wetlands, newts had similar infection intensities as P. regilla, suggesting that they commonly function as alternative hosts despite their unpalatability to downstream hosts, whereas mosquitofish had substantially lower infection intensities and are unlikely to function as hosts. These results underscore the importance of studying host-parasite interactions in complex communities and of broadly linking research on predation, biodiversity loss, and infectious diseases. 相似文献
219.
220.