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211.
The EC FARMING network (Food and Agriculture Restoration Management Involving Networked Groups) was set up to bring together the many and diverse stakeholders who would be involved in intervention following wide scale radioactive contamination of the food chain, so that acceptable strategies can be developed for maintaining agricultural production and safe food supply. The network comprises stakeholder panels in the UK, Finland, Belgium, France and Greece that have met regularly since 2001 to debate, discuss and exchange opinion on the acceptability, constraints and impact of various countermeasure options and strategies. The objectives of this paper are to consolidate the main achievements of the FARMING project over the period 2000-2004, to highlight the various difficulties that were encountered and to discuss the challenges for engaging stakeholders in off-site emergency management and long-term rehabilitation in the future.  相似文献   
212.
The cost of remediation at hazardous waste sites is estimated at billions of dollars annually. It is imperative that more cost‐effective remediation technologies be developed, particularly to address the more complex megasites. Chlorinated hydrocarbons represent the major contaminants at many such sites. It has long been recognized that chlorinated hydrocarbons can be destroyed by photocatalytic oxidation. Traditional photocatalysts, however, have often shown inadequate destruction activity, a loss of activity over time, and poor selectivity, thereby producing substantial amounts of phosgene and chloroform by‐products. This article presents results obtained using novel photocatalyst compositions. The results demonstrate the ability to achieve high photocatalytic destruction activity for chlorinated hydrocarbons with full retention of activity over extended time periods and with complete elimination of phosgene and chloroform by‐products. © 2006 Wiley Periodicals, Inc.  相似文献   
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Each year thousands of people are treated in emergency departments and trauma centers for alcohol-related injuries, including those sustained in drinking driving crashes. Emergency departments and trauma centers provide an opportunity to screen for alcohol use problems and intervene with injured or high-risk drivers to reduce future alcohol-related traffic and injury risk. Recently physicians have expressed interest in exploring screening and intervention for alcohol use problems in these venues as a means of improving clinical care. This article reviews the literature that has examined screening and brief interventions in acute care settings to reduce future alcohol consumption and alcohol-related injury. The methodological and practical issues inherent in conducting these studies as well as in actual practice are discussed. The chaotic environment of acute care, the large numbers of patients required to be screened to obtain an adequate study sample, and high attrition rates make study in these settings difficult at best and are methodological problems that should be addressed in future research. A basic question that has not been adequately answered by research to date is whether reduction in alcohol consumption will translate to reduced alcohol-related harm, such as driving while impaired, or injurious or fatal crashes. Long-term studies that assess records-based outcomes in addition to alcohol-consumption levels are needed.  相似文献   
217.
Efforts to develop multipollutant control strategies have demonstrated that adding certain oxidants to different classes of Ca-based sorbents leads to a significant improvement in elemental Hg vapor (Hg0), SO2, and NOx removal from simulated flue gases. In the study presented here, two classes of Ca-based sorbents (hydrated limes and silicate compounds) were investigated. A number of oxidizing additives at different concentrations were used in the Ca-based sorbent production process. The Hg0, SO2, and NOx capture capacities of these oxidant-enriched sorbents were evaluated and compared to those of a commercially available activated carbon in bench-scale, fixed-bed, and fluid-bed systems. Calcium-based sorbents prepared with two oxidants, designated C and M, exhibited Hg0 sorption capacities (approximately 100 microg/g) comparable to that of the activated carbon; they showed far superior SO2 and NOx sorption capacities. Preliminary cost estimates for the process utilizing these novel sorbents indicate potential for substantial lowering of control costs, as compared with other processes currently used or considered for control of Hg0, SO2, and NOx emissions from coal-fired boilers. The implications of these findings toward development of multipollutant control technologies and planned pilot and field evaluations of more promising multipollutant sorbents are summarily discussed.  相似文献   
218.
Photoperiodic time measurement is a well-documented adaptation of multicellular plants and animals to seasonal changes in the environment, but it is unclear whether unicellular organisms can exhibit bona fide photoperiodic responses. We demonstrate that the occurrence of zygospore germination of the unicellular alga Chlamydomonas is a genuine photoperiodic response. Germination efficiency is enhanced in long days as compared with short days. While the total amount of light exposure influences the efficiency of germination, the photoperiod is a significant cue for germination. The developmental stage that senses the photoperiod is just prior to mating and during the first days of zygospore development, so there may be a critical window of zygospore maturation that is regulated by photoperiod. Because zygospores are resistant to freezing injury, whereas vegetative cells are not, it is likely that the suppression of germination by short days is an adaptive response for overwintering of Chlamydomonas. Therefore, Chlamydomonas is a single-celled organism that is capable of photoperiodic responses.  相似文献   
219.
Ostergård H  Hambäck PA  Ehrlén J 《Ecology》2007,88(12):2959-2965
Oviposition sites of phytophagous insects should correlate with plant traits that maximize survival of the progeny. Plants, on the other hand, should benefit from traits and developmental patterns that complicate oviposition decisions. In the antagonistic interaction between plant and pre-dispersal seed predator the time lag between egg laying and seed development may allow for abortion of fruits in plants, potentially reducing fitness loss through predation. We studied the perennial herb Lathvrus vernus and the beetle pre-dispersal seed predator Bruchus atomarius in Sweden to determine the fitness consequences of nonrandom fruit abortion in the plant and oviposition patterns of the beetle. The beetle had a sophisticated ability to locate fruits with high probability of retention, partly by fruit position and phenology but also by some additional unidentified cue. Mortality of eggs was density dependent, but still the egg-laying pattern was clumped. We found no defensive strategy in the plant; instead the predictable fruit abortion pattern was associated with decreased plant fitness. We discuss how interactions may pose simultaneous selection pressures on plant and insect traits and how life history traits and other selective forces may shape the adaptive outcome of the interaction in plant and insect, respectively.  相似文献   
220.
Many migratory bird species have advanced their spring arrival during the latest decades, most probably due to climate change. However, studies on migratory phenology in the period before recent global warming are scarce. We have analyzed a historical dataset (1873–1917) of spring arrival to southern and central Sweden of 14 migratory bird species. In addition, we have used relative differences between historical and present-day observations (1984–2013) to evaluate the effect of latitude and migratory strategy on day of arrival over time. There was a larger change in spring phenology in short-distance migrants than in long-distance migrants. Interestingly, the results further suggest that climate change has affected the phenology of short-distance migrants more in southern than in central Sweden. The results suggest that the much earlier calculated arrival to southern Sweden among short-distance migrants mirrors a change in location of wintering areas, hence, connecting migration phenology and wintering range shifts.  相似文献   
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