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341.
In response to extreme events, researchers have recognised the convergence of volunteers, emergency responders, and other individuals and organisations. In 2000, geographer Paul Routledge presented the concept of convergence spaces as a theoretical means to explain social movements. In applying this concept, this paper explores the geographic space in which organisations and individuals converged immediately following the 11 September 2001 attacks on the World Trade Center. The paper begins to answer the question of whether there were in fact any patterns of convergence among the locations utilised by organisations responding to the attacks. Using data collected from field documents, these geographic locations are mapped over 12 days to help identify possible patterns of clustering. Results of this analysis will begin to provide researchers, policy makers and practitioners with a better understanding of how emergency response evolves geographically following an event.  相似文献   
342.
This study investigates the effects of workers' perceived participation in democratic decision‐making on their prosocial behavioral orientations, democratic values, commitment to the firm, and perceptions of socio‐moral climate. The sample consists of 325 German‐speaking employees from 22 companies in Austria, North Italy, and Southern Germany that vary in their level of organizational democracy (social partnership enterprises, workers' co‐operatives, democratic reform enterprises, and employee‐owned self‐governed firms). The findings suggest that the extent employees participate in democratic forms of organizational decision‐making is positively related to the firm's socio‐moral climate as well as to their own organizational commitment and prosocial and community‐related behavioral orientations. The results also indicate that socio‐moral climate is positively related to employees' organizational commitment. The effect of participation in decision‐making on organizational commitment is partially mediated by socio‐moral climate. Implications for promoting societal and organizational civic virtues among individuals are described. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
343.
Abstract: Our study compared the suprabenthic fauna collected in the Bay of Saint-Brieuc (western English Channel) in September 1995 and May 1996 at two sites colonized by Crepidula fornicata with that of one site where it was absent (site 23–0). Where Crepidula was present, no species dominated and abundance remained low. At the site without Crepidula , abundance was higher and the mysid Haplostylus lobatus dominated the suprabenthic community. Swimming activity of most suprabenthic species was increased by the presence of C. fornicata . The differential abundance and swimming activity of certain species are linked to the conversion of the formerly soft substrate to now hard, shelled substrate.  相似文献   
344.
345.
The Journal of Safety Research has partnered with the National Center for Injury Prevention and Control at the Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia, USA, to briefly report on some of the latest findings in the research community. This report is the fourth edition in a series of CDC articles. BACKGROUND: An active injury and illness surveillance system was established by the Centers for Disease Control and Prevention (CDC) along with the Louisiana Department of Health and Hospitals (LDHH) in the aftermath of Hurricane Katrina in functioning hospitals and medical clinics. RESULTS: The surveillance system recorded 7,543 nonfatal injuries among residents and relief workers between September 8-October 14, 2005. The leading mechanisms of injury identified in both groups were fall and cut/stab/pierce, with a greater proportion of residents compared to relief workers injured during the repopulation period. Clean-up was the most common activity at the time of injury for both groups. CONCLUSION: Injuries documented through this system underscore the need for surveillance of exposed populations to determine the injury burden and initiate injury prevention activities and health communication campaigns.  相似文献   
346.

Background

In the past, cases of PCDD/F and PCB contamination exceeding limits in food from animal origin (eggs, meat or milk) were mainly caused by industrially produced feed. But in the last decade, exceedances of EU limit values were discovered more frequently for PCDD/Fs or dioxin-like(dl)-PCBs from free range chicken, sheep, and beef, often in the absence of any known contamination source.

Results

The German Environment Agency initiated a project to elucidate the entry of PCBs and PCDD/Fs in food related to environmental contamination. This paper summarizes the most important findings. Food products from farm animals sensitive to dioxin/PCB exposure—suckling calves and laying hens housed outdoor—can exceed EU maximum levels at soil concentrations that have previously been considered as safe. Maximum permitted levels can already be exceeded in beef/veal when soil is contaminated around 5 ng PCB-TEQ/kg dry matter (dm). For eggs/broiler, this can occur at a concentration of PCDD/Fs in soil below 5 ng PCDD/F–PCB-TEQ/kg dm. Egg consumers—especially young children—can easily exceed health-based guidance values (TDI). The soil–chicken egg exposure pathway is probably the most sensitive route for human exposure to both dl-PCBs and PCDD/Fs from soil and needs to be considered for soil guidelines. The study also found that calves from suckler cow herds are most prone to the impacts of dl-PCB contamination due to the excretion/accumulation via milk. PCB (and PCDD/F) intake for free-range cattle stems from feed and soil. Daily dl-PCB intake for suckler cow herds must in average be less than 2 ng PCB-TEQ/day. This translates to a maximum concentration in grass of 0.2 ng PCB-TEQ/kg dm which is less than 1/6 of the current EU maximum permitted level. This review compiles sources for PCDD/Fs and PCBs relevant to environmental contamination in respect to food safety. It also includes considerations on assessment of emerging POPs.

Conclusions

The major sources of PCDD/F and dl-PCB contamination of food of animal origin in Germany are (1) soils contaminated from past PCB and PCDD/F releases; (2) PCBs emitted from buildings and constructions; (3) PCBs present at farms. Impacted areas need to be assessed with respect to potential contamination of food-producing animals. Livestock management techniques can reduce exposure to PCDD/Fs and PCBs. Further research and regulatory action are needed to overcome gaps. Control and reduction measures are recommended for emission sources and new listed and emerging POPs to ensure food safety.
  相似文献   
347.
Effective communication is essential to the success of collaborative ecosystem management projects. In this paper, we investigated the dynamics of the Interior Columbia Basin Ecosystem Management Projects (ICBEMP) cross-disciplinary integration process in the assessment phase. Using a case study research design, we captured the rich trail of experience through conducting in-depth interviews and collecting information from internal and public documents, videos, and meetings related to the ICBEMP. Coding and analysis was facilitated by a qualitative analysis software, NVivo. Results include the range of internal perspectives on barriers and facilitators of cross-disciplinary integration in the Science Integration Team (SIT). These are arrayed in terms of discipline-based differences, organizational structures and activities, individual traits of scientists, and previous working relationships. The ICBEMP organization included a team of communication staffs (CT), and the data described the CT as a mixed group in terms of qualifications and educational backgrounds that played a major role in communication with actors external to the ICBEMP organization but a minor one in terms of internal communication. The data indicated that the CT-SIT communication was influenced by characteristics of actors and structures related to organizations and their cultures. We conclude that the ICBEMP members may not have had a sufficient level of shared understanding of central domains, such as the task at hand and ways and timing of information sharing. The paper concludes by suggesting that future ecosystem management assessment teams use qualified communications specialists to design and monitor the development of shared cognition among organization members in order to improve the effectiveness of communication and cross-disciplinary integration.  相似文献   
348.
Impact of land use on soluble organic nitrogen in soil   总被引:1,自引:0,他引:1  
Although it has been hypothesized that soluble organic nitrogen (SON) plays a central role in regulating productivity in some terrestrial ecosystems, the factors controlling the size of the SON pool in soil remain poorly understood. Therefore our principal aim in this work was to assess the impact of seven different land use systems (rough and managed grassland, deciduous and coniferous woodland, heathland, wetland and tilled land) on the size of the SON and inorganic N (NO? 3, NH+ 4) pools in the surface soil layer (0–15 cm). After extraction with deionised water, we found that in most cases the size of the water extractable organic N (WEON) pool was similar in size to the inorganic N pool. In contrast, the KCl extractable organic N (KClEON) pool constituted the dominant form of soluble N in soils under all land uses, perhaps indicating that significant amounts were held on the soil exchange phase. In contrast to inorganic N, which varied significantly with land use, the size of the KClEON and WEON pool was similar for all land uses with the exception of KClEON in tilled land, where significantly lower amounts were observed. We conclude that SON constitutes an important soil N pool in a broad range of land uses, and that its role in microbial N assimilation, plant nutrition and ecosystem responses to atmospheric N deposition warrants further attention.  相似文献   
349.
In order to analyse potential influences of soda industryeffluents on the ecological integrity of Traunsee (TS) weinvestigated the fish community of the lake in comparison witha reference lake (Hallstättersee HS) and used a reconstructionfrom the (older) literature concerning the original speciescomposition of Traunsee. Published `Index of Biotic Integrity(IBI)' metrics were considered to be of limited value due tothe relatively low species number in the oligotrophic, Alpinelake. Therefore we included, in addition to speciescomposition, studies on egg distribution, larval fishdensities, life-history parameters (i.e. growth, maturity,fecundity, age and size composition), stress levels and heavymetal content of the dominant whitefish (Coregonuslavaretus), as well as overall fish density and biomass (usinghydroacoustics) to assess the ecological status of the fishcommunity. Two of the original 18 species have disappearedfrom the lake, presumably in connection with the introductionof non-native eel (Anguilla anguilla) and theconstruction of a power plant in the outflow. Silt from grindedlimestone together with highly alkaline pore waters is emittedvia industrial wastewater from Sodaworks and covers part of thelake bottom. We observed that eggs of whitefish were spawnedmainly in the main inflowing river and close to the shore, thusavoiding the silty areas and making the anticipated damage tothe reproductive potential of whitefish neglectable. This wascorroborated by larval surveys done weekly on both lakes fromJanuary to May, which showed halve the density of whitefishlarvae in TS compared to HS. Estimates of potentially spawningfish from hydroacoustic surveys resulted in a ratio of 1(TS) :3 (HS). Analysis of whitefish revealed that they are growingfaster in TS and have higher fecundity leading to somecompensation of lower abundance. High levels of fishing in TSmight have led to this pattern and to depressed yields asindicated by the age composition. Level of oxidative stress andheavy metal content were not discernible from the referencelake. Therefore we concluded that negative impacts on theecological status of the fish community resulted from fisheriesmismanagement and a power plant situated in the outflow of thelake, considered to have damaged spawning places for somespecies, but not from soda industry effluents.  相似文献   
350.
Smart growth policies direct development towards existing communities already served by roads, sewer systems and other infrastructure. The increased development in these communities in turn should enable them to benefit from a stronger tax-base, more efficient use of their schools and other public facilities, and the renewed economic vitality of their urban centres. These goals and objectives appear to complement and support the efforts of urban mayors to attract new property tax rateables and better-paying jobs, but they may conflict with the desires of residents to reduce densities and improve the quality of life. We use a visual GIS-based model to assist five small contiguous older suburbs individually and collectively to evaluate their current redevelopment plans and to understand the implications of their land-use decisions on the quality of life in their communities. By bringing them together as a group, and our raising broader redevelopment and impact issues, they have begun to rethink how these properties could be best used to meet the community's needs and to see them in the context of similar redevelopment plans within their mini-region. One of the changes emerging is a greater role for certain types of residential development and a concurrent reduction in the amount of commercial space being considered. The authors would like to thank the Geraldine R. Dodge Foundation for funding this project, the Somerset County Planning Board and mayors of the five towns for actively supporting and participating in the study and the Regional Planning Partnership for its co-operation and assistance in refining its GOZ model to promote regional planning from the bottom up. The authors accept full responsibility for the ideas and recommendations in this report.  相似文献   
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