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11.
IntroductionThe International Atomic Energy Agency (IAEA) organized the 3rd international conference on radiation protection (RP) of patients in December 2017. This paper presents the conclusions on the interventional procedures (IP) session.Material and methodsThe IAEA conference was conducted as a series of plenary sessions followed by various thematic sessions. “Radiation protection of patients and staff in interventional procedures” session keynote speakers presented information on: 1) Risk management of skin injuries, 2) Occupational radiation risks and 3) RP for paediatric patients. Then, a summary of the session-related papers was presented by a rapporteur, followed by an open question-and-answer discussion.ResultsSixty-seven percent (67%) of papers came from Europe. Forty-four percent (44%) were patient studies, 44% were occupational and 12% were combined studies. Occupational studies were mostly on eye lens dosimetry. The rest were on scattered radiation measurements and dose tracking. The majority of patient studies related to patient exposure with only one study on paediatric patients. Automatic patient dose reporting is considered as a first step for dose optimization. Despite efforts, paediatric IP radiation dose data are still scarce. The keynote speakers outlined recent achievements but also challenges in the field. Forecasting technology, task-specific targeted education from educators familiar with the clinical situation, more accurate estimation of lens doses and improved identification of high-risk professional groups are some of the areas they focused on.ConclusionsManufacturers play an important role in making patients safer. Low dose technologies are still expensive and manufacturers should make these affordable in less resourced countries. Automatic patient dose reporting and real-time skin dose map are important for dose optimization. Clinical audit and better QA processes together with more studies on the impact of lens opacities in clinical practice and on paediatric patients are needed.  相似文献   
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Maritime Spatial Planning (MSP) needs to incorporate spatial information on human impacts. As human activities and uses increase in marine and coastal waters around the world, pressures in ecosystems are also increasing, leading to multiple adverse effects on different species and habitats. The European Directive on MSP aims to achieve an integrated approach to marine governance, whilst securing and maintaining the healthy status of marine and coastal waters, in accordance with the Marine Strategy Framework Directive. The latter requires Member States to develop assessments not only on pressures and impacts, but also on the state of the marine environment and then take measures towards reaching a Good Environmental Status by 2020.The Portuguese Maritime Spatial Plan – Plano de Ordenamento do Espaço Marítimo (POEM) was developed between 2009 and 2012. In 2014 a law establishing the Basis for the Spatial Planning and Management of the National Maritime Space was enacted and in 2015 the framework for the elaboration of a new national Maritime Spatial Plan, named Situation Plan, was established. Portugal will face, in the next five years, the challenge of planning and managing its marine space, whilst promoting its sustainable use and protection.This study adapted a cumulative effects assessment model to understand how the impacts from multiple threats affect the marine and coastal ecosystems and, how this information can be used to improve the management process. Information was gathered on intensity and distribution of activities and uses for the Portuguese continental subdivision marine area, quantified and mapped their cumulative impacts in marine ecosystems, and overlapped with the POEM. Results show that impacts are spreading from the coast up to the Contiguous Zone. Higher scores appear in Transitional and Coastal Waters in the north (Viana do Castelo/Figueira da Foz), centre (Peniche/Setúbal) and south (Lagos/Faro). In some areas with higher ranks, statutes of nature conservation are already in place, but potential activities may still occur on top of existing ones. This study shows that the adapted model is a helpful tool to clarify ocean planning, identify areas of potential conflicts among users and support the decision making process.  相似文献   
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A set of eight simple ecological and social principles is proposed that could enhance the understanding of what constitutes fish 'habitat' and, if implemented, could contribute to improved management and conservation strategies. The habitat principles are a small, interrelated sub‐set that may be coupled with additional ones to formulate comprehensive guidelines for management and conservation strategies. It is proposed that: 1) habitat can be created by keystone species and interactions among species; 2) the productivity of aquatic and riparian habitat is interlinked by reciprocal exchanges of material; 3) the riparian zone is fish habitat; 4) fishless headwater streams are inseparable from fish‐bearing rivers downstream; 5) habitats can be coupled – in rivers, lakes, estuaries and oceans, and in time; 6) habitats change over hours to centuries; 7) fish production is dynamic due to biocomplexity, in species and in habitats; 8) management and conservation strategies must evolve in response to present conditions, but especially to the anticipated future. It is contended that the long‐term resilience of native fish communities in catchments shared by humans depends on incorporating these principles into management and conservation strategies. Further, traditional strategies poorly reflect the dynamic nature of habitat, the true extent of habitat, or the intrinsic complexity in societal perspectives. Forward‐thinking fish management and conservation plans view habitat as more than water. They are multilayered, ranging from pools to catchments to ecoregions, and from hours to seasons to centuries. They embrace, as a fundamental premise, that habitat evolves through both natural and anthropogenic processes, and that patterns of change may be as important as other habitat attributes.  相似文献   
14.
The liver leaf, Hepatica nobilis (Ranunculaceae), is a perennial forest understory herb with specific habitat requirements, which occurs on calcareous soils in beech and oak forests. In Bavaria it can be found, therefore, only in four geographic regions, which are Franconia, the Franconian-Swabian Jura, the prealpine transitions region and the prealpine moraine belt with the Alps. In German forestry, provenance delineations are used since 1987. Similarly for herbs seed provenances and production areas are applied in commercial seed production and restoration. In this study we analyzed whether the genetic variation of H. nobilis reflects the geographic distribution of the species in Bavaria or the provenance delineations used for seed production.We applied AFLPs to study genetic variation within and between 24 populations of H. nobilis.Our analysis revealed high levels of genetic variation within and moderate variation between populations. Variation between seed production areas and seed provenances was low and comparable to the variation between geographic regions. Genetic variation within populations or rare fragments did not differ between production areas, provenances or geographic regions. A significant positive relation of genetic and geographic distances was present within 100 km.Pollination and seed dispersal seem mainly to happen within populations of the myrmecochorous H. nobilis, whereas long-distance dispersal is presumably occasional and random. Our study supports the relevance of dispersal traits for seed collections used in conservation. The protection of historically old beech and oak forests is exceedingly important to preserve the genetic variation of H. nobilis in Bavaria.  相似文献   
15.
The mechanism of mass collaboration in risk management was studied during the Sichuan earthquake under a Web-based “PeopleFinder” project, where information is contributed and shared among mass contributors. The case study is provided by a great earthquake that happened in Wenchuan County, Sichuan Province, of southwestern China at 2:28 p.m. on May 12, 2008. We witnessed and experienced the rescue and relief efforts for the great earthquake. In this article, two fundamental frameworks are developed to study the mechanism of mass collaboration. Mass collaboration is proven to be effective in a big public crisis such as the Sichuan earthquake.  相似文献   
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Appropriate final disposal of sewage sludge (SS) generated by wastewater treatment plants (WWTP) has been considered a serious environmental problem, but also a viable alternative to be applied in agriculture, once SS is rich in organic matter and nutrients. However, SS can be a source of contamination of several toxic agents. Therefore, its use in agriculture requires special care to avoid possible damage to the environment and exposed organisms. Detoxification of toxic wastes can be performed using the monitored natural attenuation, which involves biological, physical and chemical processes that frequently occur in the environment. This study aimed to assess the feasibility of decontaminating SS after different periods of monitored natural attenuation. To this end, samples of SS and associations of soil/SS with proportions of 10, 25 and 50% SS were buried for 0, 2, 6 and 12 months in holes prepared in a place free of contamination. Allium cepa was used as an indicator to assess the efficiency of the natural attenuation process. According to chemical analysis, the SS samples presented a high concentration of m- and p-cresol, especially for samples analyzed after 0 or 2 months of natural attenuation. The microorganisms present in the SS belonged to 17 different genera of bacteria, which varied in the microbial composition among samples. Both, raw SS and aqueous SS extracts induced DNA damage in A. cepa, even when associated with soil. However, this effect was observed to decline during the attenuation period, although significant effects were detected for the highest tested concentration (100% SS) even at the end of this process. These results thus indicated the necessity of applying a stabilization process associating SS and soil for a period of at least 12 months and showed that the studied raw SS is not a viable material for use as a soil reconditioner, even after natural attenuation. A. cepa test proved to be a useful tool to assess the efficiency of SS detoxification process. Therefore, we suggest that the application of SS in agriculture should be approached with caution and that the SS must be previously submitted to methodologies that evaluate its toxic potential.  相似文献   
19.
We have compared the species richness of medicinal plants and the differential patterns of use amongst settlements in the Andean communities of Northwest Argentina which have differing levels of isolation. About 259 ethnoespecies, belonging to 74 plant families, were included, representing between 70 and 80% of the total estimate. The results indicate that Coronopus didymus is the most relevant and important species. The method of use of medicinal plants and the ailments treated by rural doctors compared to those of the layperson is different. Native and exotic plants are used differently according to the body system treated. There are some relationships between internal and external use and body systems and recipes. The greater medicinal species richness found in the less isolated locations is due to external enriching cultural influences.  相似文献   
20.
Almost all primates experience seasonal fluctuations in the availability of key food sources. However, the degree to which this fluctuation impacts foraging behavior varies considerably. Eastern chimpanzees (Pan troglodytes schweinfurthii) in Nyungwe National Park, Rwanda, live in a montane forest environment characterized by lower primary productivity and resource diversity than low‐elevation forests. Little is known about chimpanzee feeding ecology in montane forests, and research to date predominantly relies on indirect methods such as fecal analyses. This study is the first to use mostly observational data to examine how seasonal food availability impacts the feeding ecology of montane forest chimpanzees. We examine seasonal changes in chimpanzee diet and fallback foods (FBFs) using instantaneous scan samples and fecal analyses, supported by inspection of feeding remains. Chimpanzee fruit abundance peaked during the major dry season, with a consequent change in chimpanzee diet reflecting the abundance and diversity of key fruit species. Terrestrial herbaceous vegetation was consumed throughout the year and is defined as a “filler” FBF. In contrast to studies conducted in lower‐elevation chimpanzee sites, figs (especially Ficus lutea) were preferred resources, flowers were consumed at seasonally high rates and the proportion of non‐fig fruits in the diet were relatively low in the current study. These divergences likely result from the comparatively low environmental diversity and productivity in higher‐elevation environments.  相似文献   
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