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1.
For many citizens and policymakers, the empirical relationship between economic growth and biodiversity conservation has not been sufficiently established for purposes of identifying the types of economic policies amenable to biodiversity conservation. Some think economic growth conflicts with biodiversity conservation; others think economic growth conduces biodiversity conservation. With panel data from 1997‐2011, encompassing US continental states, we developed a series of statistical models to investigate the relationships among species endangerment, human population, and economic growth as indicated by GDP and per capita GDP. Species endangerment is highly correlated with population and GDP, and per capita GDP is a significant regressor of species endangerment. Across US continental states, competitive exclusion of non‐human species occurs via human economic growth and population growth.  相似文献   
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长白山温带森林挥发性有机物的排放通量   总被引:2,自引:1,他引:1  
2010年夏季,在长白山温带森林开展了挥发性有机物(VOC)排放通量以及气象参数、PAR的综合测量.VOC排放通量采用松弛涡度积累(RelaxedEddyAccumulation)技术在森林冠层上进行测量.初步发现长白山阔叶林主要排放α-蒎烯、β-蒎烯、莰烯、香桧烯、月桂烯、蒈烯、柠檬烯、罗勒烯、松油烯、繖花烃、萜品油烯、三环烯等.研究表明,长白山阔叶混交林VOC排放有明显的日变化——早晚较低和中午前后较高.2010年夏季,单萜烯总排放通量的平均值为0.242mg·m·h-2-1,其变化范围为0.005~1.668mg·m·h-2-1;各成分排放通量的平均值(和最大值)分别为α-蒎烯0.072(0.234)、莰烯0.028(0.356)、月桂烯0.027(0.433)、蒈烯0.023(0.173)、柠檬烯0.037(0.197)、罗勒烯0.016(0.168)、萜品油烯0.053(0.320)、繖花烃0.067(0.755)mg·m·h-2-1.研究还发现VOC排放通量与气温之间存在一定的联系.  相似文献   
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Photochemical degradation of 1-nitropyrene, 2-nitrofluorene, 2,7-dinitrofluorene, 6-nitrochrysene, 3-nitrofluoranthene, 5-nitroacenaphthene, and 9-nitroanthracene was examined in CHCl3, CH2Cl2, DMF, DMF/H2O (80/20), CH3CN, or CH3CN/H2O (80/20). The degradation mostly follows the first order kinetics; but a few follow second order kinetics or undergo self-catalysis. The photodegradation rates follow the order: CHCl3 > CH2Cl2 > DMF > DMF/H2O > CH3CN > CH3CN/H2O. DMF is an exceptional solvent because three of the seven compounds undergo self-catalytic reaction. 9-Nitroanthracene, which has a perpendicular nitro group, is the fastest, while the more compact 1-nitropyrene and 3-nitrofluoranthene are the slowest degrading compounds.  相似文献   
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Problem

Exercise-based research interventions demonstrate reduced risk and rates of falls for community dwelling older adults; however, little is known about effective mechanisms for the translation, implementation, and maintenance of these interventions in community settings.

Method

The RE-AIM framework was used to assess the translatability of an effective exercise-based research intervention in a community setting. Questions included: Reach — Would the target population attend? Effectiveness — What was the adherence and compliance to the program? Were there individual improvements in falls risk factors? Adoption: Would staff at the center adopt the program and offer it past the funding period? Implementation — What adaptations, including optimal frequency and duration, should be made to meet the community needs, still adhere to core elements and achieve similar outcomes? Maintenance — Would the program be sustained by our community partners?

Discussion

The process of translating a controlled research intervention targeting older adults at risk of falls into a community setting was challenging. Licensed professionals developed the infrastructure to safely and effectively deliver the program. The end product was highly appealing program to our target audience, resulted in improved outcomes and was successfully adopted and maintained by the community partner.

Summary

Partnerships between community and healthcare providers are key to successful implementation of falls prevention interventions. Lessons learned from this experience can be applied to the translation of future exercise-based falls prevention interventions.  相似文献   
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The prenatal diagnosis of the cerebro-hepato-renal syndrome of Zellweger (CHRS) was made by assaying the levels of very long chain fatty acids (VLCFAs) in amniotic fluid cell cultures, obtained by amniocentesis at 16 1/2 weeks of pregnancy. The family-at-risk, because they had previously borne a child with CHRS, accepted these results as indications of an affected fetus, and chose to terminate the pregnancy at 20 1/2 weeks of gestation. The diagnosis was confirned by the phenotype of the aborted fetus and the presence of markedly elevated levels of VLCFAs in fetal liver homogenates. The prenatal diagnosis of CHRS, which can now readily be determined from amniotic fluid cell cultures, is an important step in genetic counselling of families-at-risk for this disease.  相似文献   
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Invasive species pose significant ecological costs, and therefore successful management techniques are important. One commonly employed method is biological control. The success of biological control depends largely on whether additional inflicted damage can successfully reduce the fitness and population growth rate of a target species. Here, we simulate herbivory on the invasive Lespedeza cuneata and create stage-structured projection models to determine if augmented herbivory by a leaf-chewing biological control agent would regulate the population growth rate of this species. We found that augmented herbivory influenced stage transitions of plants in the smallest stage class, causing higher mortality and reduced growth. No other effect was found on stage transitions or fecundities, despite manipulation of herbivory at exceptionally high levels (up to 80% leaf loss). None of the clipping treatments significantly reduced the population growth rate of L. cuneata. We conclude that biological control by a leaf chewing herbivore would not likely be successful, even if an exceptionally large amount of each plant were consumed. We suggest that this approach, a combination of simulated herbivory and demographic modeling, will provide essential information for understanding the utility of biological control to curb the population growth of invasive plant species.  相似文献   
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Mainstreaming climate change adaptation (CCA) into plans and programs is still a new approach in adaptation and thus there is limited information on how to operationalize it on-ground. This paper addresses this gap by investigating the challenges in mainstreaming CCA into the local land use plans in the province of Albay, Philippines. Specifically, this paper developed 20 quantitative “mainstreaming indicators” to assess the state-of-play and the challenges for local mainstreaming. These indicators were classified under three groupings, namely, the information, institutional, and resource capacities of systems. Qualitative analysis of the indicator scores suggested that developing the institutional capacities of local governments is crucial in the local mainstreaming process. Likewise, the results highlighted the “institutional issues” indicator as the primary barrier in operationalizing the approach. These institutional issues are: fragmented laws and regulations; overlapping policy requirements; and the lack of guidelines for mainstreaming CCA into the local land use plans. Meanwhile, the “leadership” indicator, as signified by a climate change champion in Albay, was evaluated as an opportunity for local mainstreaming. The champion effectively led the CCA efforts because the existing institutional mechanisms supported the champion’s capacity to influence the behavior of people and produce collective action towards CCA.  相似文献   
10.
Large marine protected areas (MPAs) of unprecedented size have recently been established across the global oceans, yet their ability to meet conservation objectives is debated. Key areas of debate include uncertainty over nations’ abilities to enforce fishing bans across vast, remote regions and the intensity of human impacts before and after MPA implementation. We used a recently developed vessel tracking data set (produced using Automatic Identification System detections) to quantify the response of industrial fishing fleets to 5 of the largest MPAs established in the Pacific Ocean since 2013. After their implementation, all 5 MPAs successfully kept industrial fishing effort exceptionally low. Detected fishing effort was already low in 4 of the 5 large MPAs prior to MPA implementation, particularly relative to nearby regions that did not receive formal protection. Our results suggest that these large MPAs may present major conservation opportunities in relatively intact ecosystems with low immediate impact to industrial fisheries, but the large MPAs we considered often did not significantly reduce fishing effort because baseline fishing was typically low. It is yet to be determined how large MPAs may shape global ocean conservation in the future if the footprint of human influence continues to expand. Continued improvement in understanding of how large MPAs interact with industrial fisheries is a crucial step toward defining their role in global ocean management.  相似文献   
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