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排序方式: 共有262条查询结果,搜索用时 15 毫秒
111.
Amanda Guidero 《Disasters》2022,46(1):162-184
Attacks against humanitarian aid workers have received increasing attention in the media, particularly high-profile incidents such as those against the hospitals of Médecins Sans Frontières in Afghanistan, Syria, and Yemen. Concurrently, scholarly research has given rise to a number of articles, white papers, and books on humanitarian insecurity. Most of this work centres on external threats, neglecting the internal mechanisms that humanitarian organisations use to mitigate security situations. This paper builds on the existing literature by focusing on the decision-making processes of humanitarian organisations, drawing on data collected from 16 security managers or advisers. The findings reveal that several factors contribute to contextual uncertainty and complexity, including recipient perceptions, local government actions, the behaviour of other non-governmental organisations (NGOs) in the area, logistical issues, risk variance within a single location, and organisational mandate. Furthermore, the results indicate that NGOs utilise a combination of decision-making processes to determine how to manage security in high-risk environments. 相似文献
112.
Studying citizen science through adaptive management and learning feedbacks as mechanisms for improving conservation 下载免费PDF全文
Rebecca Jordan Steven Gray Amanda Sorensen Greg Newman David Mellor Greg Newman Cindy Hmelo‐Silver Shannon LaDeau Dawn Biehler Alycia Crall 《Conservation biology》2016,30(3):487-495
Citizen science has generated a growing interest among scientists and community groups, and citizen science programs have been created specifically for conservation. We examined collaborative science, a highly interactive form of citizen science, which we developed within a theoretically informed framework. In this essay, we focused on 2 aspects of our framework: social learning and adaptive management. Social learning, in contrast to individual‐based learning, stresses collaborative and generative insight making and is well‐suited for adaptive management. Adaptive‐management integrates feedback loops that are informed by what is learned and is guided by iterative decision making. Participants engaged in citizen science are able to add to what they are learning through primary data collection, which can result in the real‐time information that is often necessary for conservation. Our work is particularly timely because research publications consistently report a lack of established frameworks and evaluation plans to address the extent of conservation outcomes in citizen science. To illustrate how our framework supports conservation through citizen science, we examined how 2 programs enacted our collaborative science framework. Further, we inspected preliminary conservation outcomes of our case‐study programs. These programs, despite their recent implementation, are demonstrating promise with regard to positive conservation outcomes. To date, they are independently earning funds to support research, earning buy‐in from local partners to engage in experimentation, and, in the absence of leading scientists, are collecting data to test ideas. We argue that this success is due to citizen scientists being organized around local issues and engaging in iterative, collaborative, and adaptive learning. 相似文献
113.
Amanda D. Boyd 《Environmental Communication: A Journal of Nature and Culture》2017,11(2):184-204
An increasing demand for the development and implementation of low carbon energy systems has furthered the need to understand the factors that influence a community's support for or opposition to local energy developments. Carbon dioxide capture and geological storage (CCS) is one such energy system where it is widely acknowledged that public perceptions and acceptance of CCS technologies are critical to their implementation. CCS refers to the capture of carbon dioxide emissions from industrial sources and the long-term storage of these emissions in stable underground reservoirs. This case study examines how place attachment and community networks factored into resident's perceptions of a proposed CCS project that was ultimately canceled due to local opposition. Participants were concerned about preserving shared places, spaces, and interactions that were valued by community members. Results demonstrate the need to ascertain how locally affected populations view CCS or other energy developments, especially with regard to their ideas about community, sense of place (ties to area and local relationships), and how they communicate about those factors. Such factors are important given the initiative to develop low carbon energy systems in rural areas. 相似文献
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Amanda J. Hess Peggy A. Johnson 《Journal of the American Water Resources Association》2001,37(1):213-221
ABSTRACT: The environment surrounding urban streams imposes constraints upon stream enhancement projects. Constraints include bridges, culverts, highways, sewer and water lines, lack of easements, and other floodplain structures. The consequences of failure of these infrastructure constraints can be significant and should be considered in the design process. Fault tree analysis provides a systematic technique for analyzing the interactions of events that could lead to infrastructure failure. A case study of a stream in Pittsburgh, Pennsylvania, shows that fault tree analysis can effectively model the interactions between the stream system and the infrastructure constraints and predict the most likely modes of failure. In addition, the relative success of alternative designs and failure mitigation techniques can be assessed using this analysis tool, lending insight into the urban stream enhancement design process. The method could also provide justification in the design permitting process and input for risk assessment. 相似文献
118.
The fauna of deep-sea hydrothermal vents are among the most isolated and inaccessible biological communities on Earth. Most vent sites can only be visited by subsea vehicles, which can and do move freely among these communities. Researchers assume individuals of the regionally homogeneous vent fauna are killed by the change in hydrostatic pressure the animals experience when the subsea vehicles, which collected them, rise to the surface. After an Alvin dive, we found 38 apparently healthy individuals of a vent limpet in a sample from a hydrothermally inactive area. Prompted by our identification of these specimens as Lepetodrilus gordensis, a species restricted to vents 635 km to the south of our dive site, we tested whether they were from a novel population or were contaminants from the dive made 36 h earlier. The 16S gene sequences, morphology, sex ratio, bacterial colonies, and stable isotopes uniformly indicated the specimens came from the previous dive. We cleaned the sampler, but assumed pressure changes would kill any organisms we did not remove and that the faunas of the 2 areas were nearly identical and disease-free. Our failure to completely clean the gear on the subsea vehicle meant we could have introduced the species and any diseases it carried to a novel location. Our findings suggest that the nearly inaccessible biological communities at deep-sea vents may be vulnerable to anthropogenic alteration, despite their extreme physical conditions. 相似文献
119.
AbstractObjective: Focusing on children (0–17?years), this study aimed to investigate injury and accident characteristics for bicyclists and to evaluate the use and protective effect of bicycle helmets.Method: This nationwide Swedish study included children who had visited an emergency care center due to injuries from a bicycle crash. In order to investigate the causes of bicycle crashes, data from 2014 to 2016 were analyzed thoroughly (n?=?7967). The causes of the crashes were analyzed and categorized, focusing on 3 subgroups: children 0–6, 7–12, and 13–17?years of age. To assess helmet effectiveness, the induced exposure approach was applied using data from 2006 to 2016 (n?=?24,623). In order to control for crash severity, only bicyclists who had sustained at least one Abbreviated Injury Scale (AIS) 2+ injury (moderate injury or more severe) in body regions other than the head were included.Results: In 82% of the cases the children were injured in a single-bicycle crash, and the proportion decreased with age (0–6: 91%, 7–12: 84%, 13–17: 77%). Of AIS 2+ injuries, 8% were head injuries and 85% were injuries to the extremities (73% upper extremities and 13% lower extremities). Helmet use was relatively high up to the age of 10 (90%), after which it dropped. Helmets were much less frequently used by teenagers (14%), especially girls. Consistently, the share of head injuries increased as the children got older. Bicycle helmets were found to reduce all head injuries by 61% (95% confidence interval [CI], 10: +/? 10%) and AIS 2+ head injuries by 68% (95% CI, 12: +/? 12%). The effectiveness in reducing face injuries was lower (45% CI +/? 10% for all injuries and 54% CI +/? 32% for AIS2+ injuries).Conclusions: This study indicated that bicycle helmets effectively reduce injuries to the head and face. The results thus point to the need for actions aimed at increasing helmet use, especially among teenagers. Protective measures are necessary to further reduce injuries, especially to the upper extremities. 相似文献
120.
Low Ca/Mg ratios (a defining component of serpentine soils) and low water environmental conditions often co-occur in nature and are thought to exert strong selection pressures on natural populations. However, few studies test the individual and combined effects of these environmental factors. We investigated the effects of low Ca/Mg ratio and low water availability on plant leaf, stem, stolon, and floral traits of Mimulus guttatus, a bodenvag species, i.e., a species that occurs in serpentine and non-serpentine areas. We quantified genetic variation and genetic variation for plasticity for these leaf, stem, stolon, and floral traits at three hierarchical levels: field-habitat type, population, and family, and we evaluated the relative importance of local adaptation and plasticity. We chose two populations and 10 families per population from four distinct field "habitat types" in northern California: high Ca/Mg ratio (non-serpentine) and season-long water availability, high Ca/Mg ratio and seasonally drying, low Ca/Mg ratio (serpentine) and season-long water availability, and low Ca/Mg ratio and seasonally drying. Seedlings were planted into greenhouse treatments that mimicked the four field conditions. We only detected genetic variation for stem diameter and length of longest leaf at the field-habitat level, but we detected genetic variation at the family level for nearly all traits. Soil chemistry and water availability had strong phenotypic effects, alone and in combination. Our hypothesis of an association between responses to low water levels and low Ca/Mg ratio was upheld for length of longest leaf, stem diameter, corolla width, and total number of reproductive units, whereas for other traits, responses to Ca/Mg ratio and low water were clearly independent. Our results suggest that traits may evolve independently from Ca/Mg ratios and water availability and that our focal traits were not simple alternative measures of vigor. We found genetic variation for plasticity both at the field-habitat type and family levels for half of the traits studied. Phenotypic plasticity and genetic variation for plasticity appear to be more important than local adaptation in the success of these M. guttatus populations found across a heterogeneous landscape in northern California. Phenotypic plasticity is an important mechanism maintaining the broad ecological breadth of native populations of M. guttatus. 相似文献