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221.
Archetypical patterns and trajectories of land systems in Europe   总被引:1,自引:0,他引:1  
Regional Environmental Change - Assessments of land-system change have dominantly focused on conversions among broad land-use categories, whereas intensity changes within these categories have...  相似文献   
222.
The Instituto de Radioprote??o e Dosimetria has been coordinating the National Intercomparison Program (PNI) for 15 years, from 1991 to 2005. The objective is to evaluate the analytical performance of the laboratories in low-level activity concentration radionuclide assays in environmental samples. This work presents an evaluation of PNI data from 42 intercomparison runs, which distributed to 22 Brazilian laboratories 2511 samples evaluating 5768 radionuclide assays involving 32 radionuclides in the period from 1991 to 2004. The laboratory performance was evaluated using the Normalized Standard Deviation used by the U.S. EPA. For comparison aims, the Normalized Deviation, used by BIPM was also applied. Laboratory performance were grouped and evaluated in three periods of 5 years each. The first period shows, an average value of good performance of 71.2%, the second shows an average of 78.6% and the last an average of 82.3%. Performance for each kind of radionuclide is also presented.  相似文献   
223.
We report results of air monitoring started due to the recent natural catastrophe on 11 March 2011 in Japan and the severe ensuing damage to the Fukushima Dai-ichi nuclear reactor complex. On 17-18 March 2011, we registered the first arrival of the airborne fission products 131I, 132I, 132Te, 134Cs, and 137Cs in Seattle, WA, USA, by identifying their characteristic gamma rays using a germanium detector. We measured the evolution of the activities over a period of 23 days at the end of which the activities had mostly fallen below our detection limit. The highest detected activity from radionuclides attached to particulate matter amounted to 4.4 ± 1.3 mBq m−3 of 131I on 19-20 March.  相似文献   
224.
The increasing number of nanomaterial based consumer products raises concerns about their possible impact on the environment. This study provides an assessment of the effluent from a commercially available silver nanowashing machine. The washing machine released silver in its effluent at an average concentration of 11μgL(-1), as determined by inductive coupled mass spectrometry (ICP-MS). The presence of silver nanoparticles (AgNPs) was confirmed by single particle ICP-MS as well as ion selective electrode measurements and filtration techniques. Size measurements showed particles to be in the defined nanosize range, with an average size of 10nm measured with transmission electron microscopy (TEM) and 60-100nm determined with nanoparticle tracking analysis (NTA). The effluent was shown to have negative effects on a natural bacterial community as its abundance was clearly reduced when exposed to the nanowash water. If washing machines capable of producing AgNPs become a common feature of households in the future, wastewater will contain significant loadings of AgNPs which might be released into the environment.  相似文献   
225.
Environmental education strategies have customarily placed substantial focus on enhancing ecological knowledge and literacy with the hope that, upon discovering relevant facts and concepts, participants will be better equipped to process and dissect environmental issues and, therefore, make more informed decisions. The assumption is that informed citizens will become active citizens––enthusiastically lobbying for, and participating in, conservation‐oriented action. We surveyed and interviewed and used performance data from 432 participants in the Coastal Observation and Seabird Survey Team (COASST), a scientifically rigorous citizen science program, to explore measurable change in and links between understanding and action. We found that participation in rigorous citizen science was associated with significant increases in participant knowledge and skills; a greater connection to place and, secondarily, to community; and an increasing awareness of the relative impact of anthropogenic activities on local ecosystems specifically through increasing scientific understanding of the ecosystem and factors affecting it. Our results suggest that a place‐based, data‐rich experience linked explicitly to local, regional, and global issues can lead to measurable change in individual and collective action, expressed in our case study principally through participation in citizen science and community action and communication of program results to personal acquaintances and elected officials. We propose the following tenets of conservation literacy based on emergent themes and the connections between them explicit in our data: place‐based learning creates personal meaning making; individual experience nested within collective (i.e., program‐wide) experience facilitates an understanding of the ecosystem process and function at local and regional scales; and science‐based meaning making creates informed concern (i.e., the ability to discern both natural and anthropogenic forcing), which allows individuals to develop a personalized prioritization schema and engage in conservation action.  相似文献   
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THINNESS CHART     
Julia Verney 《Disasters》1981,5(1):77-78
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228.
Founded on the assumption that communicator style is situationally and contextually influenced, this study investigates the effects of job-related stress on communicator style. It was specifically designed to measure the effects of job-related stress factors on employee communicator style within the context of a medical center organization. Three central research questions are posed: (1) what, if any, meaningful differences in communicator style can be found from general work conditions to stress-specific conditions; (2) do different stress conditions give rise to meaningful differences in communicator style; (3) what communicator style differences exist among three major medical center employee hierarchies in response to stress-specific situations. The results indicate that communicator style in the stress-specific sample was significantly more dominant, open, attentive but less dramatic and friendly. Multivariate analysis revealed that communicator style accounted for the greatest differences between employees who were experiencing stress due to being unprepared to perform their work role. All role-related stress variables were more powerfully discriminated by the communicator style variables than department/unit stress (stress at the work group level). Finally, communicator style variables provided statistically significant discrimination of three occupational groups: physicians, administrators/managers, and line employees. Physicians appeared to be more assertive and less supportive in their communication; administrators/managers were assertive but also supportive while line employees were both submissive and supportive in their communicator style. These three employee groups were also discriminated using the job-related stress variables. Although statistically significant findings were obtained, the discriminant functions were less powerful than the communicator style discriminant functions.  相似文献   
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The city of San José, California, USA, has a widely recognized integrated waste management program and is currently diverting close to 50% of its waste stream from landfill disposal. This paper describes the residential and commercial components of the city's waste management program. Information is presented on performance (e.g., types and quantities of materials that are collected, processed, and disposed of), customer service, and costs associated with the program. Received: October 4, 2000 / Accepted: February 15, 2001  相似文献   
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