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251.
The metabolism of the environmental estrogen bisphenol A (BPA) was studied in heterotrophic plant cell suspension cultures of soybean (Glycine max), wheat (Triticum aestivum), foxglove (Digitalis purpurea), and thorn apple (Datura stramonium), which were regarded as metabolic model systems for intact plants. Three main metabolic routes of BPA were observed in the tissues. Most of the radioactivity found in the cell extracts consisted of carbohydrate conjugates of BPA amounting to about 85% (foxglove), 80% (wheat), 7% (soybean) and 15% (thorn apple) of applied 14C. The second main route was formation of non-extractable residues. Portions detected were low in foxglove (3.9% of applied 14C), moderate in wheat (13.5%), high in thorn apple (27.4%) and soybean (49.4%). With thorn apple, BPA derived bound residues were preponderantly resistant towards acid treatment; only traces of BPA were released. The third route was the formation of a highly polar, presumably polymeric material detected in media of soybean and thorn apple (29.3% and 36.0% of applied 14C, respectively). The mechanism of its formation remained unknown. In thorn apple, this highly polar material was formed extremely rapidly, and was considerably stable. Only traces of BPA were liberated by hydrolytic treatment with cellulase or acid. During hydrolysis experiments with glycoside fractions, non-extractable residues and highly polar materials, low amounts of presumably primary metabolites of BPA (up to 6% of applied 14C) were detected besides the parent compound; their chemical structures remained unclear.  相似文献   
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Increased and intensified pig production has raised the needs for proper management systems of pig manure in order to reduce negative environmental impacts. The objectives of this study were to identify the most significant environmental impacts from pig manure management considering a wide range of impact categories and to determine which integrated technology system at which handling stage can achieve the highest impact reduction. Twelve scenarios applying various treatment, storage and land application systems were developed and compared. Life cycle assessment (LCA) with the aim of capturing the actual consequences of the considered scenarios was selected as the tool for impact quantification. The most important impact categories in this investigation are global warming (GWP), aquatic eutrophication (AEP), respiratory inorganics (RIP), and terrestrial eutrophication (TEP). The two latter impacts, caused by ammonia emissions, have not been widely considered in most of previous LCA studies on pig manure management. The main keys for the effective impact reduction are the integration of treatment technology systems aiming at energy recovery with high nutrient recovery and control of greenhouse gas, ammonia, and nitrate emissions at every handling stage. For GWP and AEP, the anaerobic digestion-based scenario with natural crust storage achieves the highest impact reduction because of high efficiencies in energy and nutrient recovery with restricted emissions of GHG and nitrate. For RIP and TEP, the incineration and thermal gasification based scenarios and the scenario without a treatment system applying the deep injection method yield the highest impact minimisation due to the lowest ammonia emissions. This study further indicates the need to consider all significant impacts to decide the best management options taking into consideration local conditions.  相似文献   
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Background, aim and scope On behalf of the Centre of Excellence for Climate Effects and Adaption (KomPass) of the German Federal Environment Agency (UBA) an Expert Information System on Climate Change and Adaption (FISKA) was developed. FISKA shall provide the governmental institutions with basic information and models on climate change impacts for the development and accomplishment of adaption strategies. In this paper the impact model on potential temperature-dependent malaria transmissions is presented. It shows how, together with the REMO and WettReg climate models implemented in FISKA, areas at risk of malaria can be identified. Materials and methods FISKA was developed as an open and modular expert information system and allows the exchange of data and information with other institutions. Climate change impacts are implemented as calculation engines. The system allows for implementing additional data and impact models to improve existing impact models. For the calculation of the temperature-dependent potential secondary malaria infections the basic reproduction rate was used and the according algorithms were implemented in two calculation engines. One engine allows the calculation of the secondary infections and the other allows the calculation of the seasonal transmission gates. Measured air temperatures for the period 1961–2007 were provided by the German Meteorological Service (DWD), data on future air temperatures were extracted from the climate models REMO and WettReg for the climate reference periods 1991–2020, 2021–2050, and 2051–2080. The respective secondary infections and the resulting seasonal transmission gates for each period were regionalised on the basis of an ecological land classification to analyse significant ecoregional differences. Results Comparing the climate reference period 1961–1990 and the following period 1991–2007, the proportion of Germany featuring a potential seasonal malaria transmission gate of one or rather two months has been reduced in favour of a three months transmission gate. Accordingly, in the period 1991–2007 malaria transmissions during three months are possible on 70?% of the German territory instead of 26?% in 1961–1990. The percentage of a four months transmission gate has increased from 0.02?% to 0.76?%, and even a five months transmission is possible on 0.15?% of Germany. For future periods the number of potential secondary infections increases and further extensions of the seasonal transmission gates were revealed. In case of REMO A1B in 2051–2080, almost whole Germany features thermal conditions allowing malaria transmissions during four or rather five months. Discussion Rising air temperatures lead to changes in the spatial structure of the ecological elementary factor temperature, which can, under otherwise identical conditions, facilitate the reproduction of pathogens (here Plasmodium vivax) and vectors (here Anopheles atroparvus) as well as the spread of diseases. The basic reproduction rate serves the calculation of secondary malaria infections, which are the infections of host by a vector under the assumption that every member of the host population is susceptible for the pathogen. Improved thermal conditions alone do not necessarily imply the development of a malaria epidemic. Other factors like population density or medical care and the presence of vector habitats are of major importance, however, not considered by the calculation engines. The example of malaria is intended to be a model for a range of temperature-dependent vector-borne diseases. Conclusions The impact model on temperature-dependent malaria infections shows exemplarily the information content and functionality of FISKA. Data and functionality of FISKA serve as an expert information system for the detection of risks due to climate change. The results can be published as interactive maps via the FISKA internet interface. From a technical point of view, every impact model based on a calculation engine can be implemented and published via the web interface, provided that the impact models and the resulting risk maps rely on scientific reliable assumptions and are documented comprehensively. Recommendations and perspectives An improvement of FISKA considering the European scale is technically possible. It would require the development of GIS- and model applications on the basis of Europe-wide basic and specific data. For small-scale model runs a dynamic modelling of the water balance including soil hydrology as well as consideration of microclimate effects are required.  相似文献   
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The Municipal Solid Waste Management (MSWM) sector has developed considerably during the past century, paving the way for maximum resource (materials and energy) recovery and minimising environmental impacts such as global warming associated with it. The current study is assessing the historical development of MSWM in the municipality of Aalborg, Denmark throughout the period of 1970 to 2010, and its implications regarding Global Warming Potential (GWP100), using the Life Cycle Assessment (LCA) approach. Historical data regarding MSW composition, and different treatment technologies such as incineration, recycling and composting has been used in order to perform the analysis. The LCA results show a continuous improvement in environmental performance of MSWM from 1970 to 2010 mainly due to the changes in treatment options, improved efficiency of various treatment technologies and increasing focus on recycling, resulting in a shift from net emission of 618 kg CO2-eq. tonne?1 to net saving of 670 kg CO2-eq. tonne?1 of MSWM.  相似文献   
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The protection and sustainable management of habitat trees is an integral part of modern forest nature conservation concepts such as retention forestry. Bats, cavity-nesting birds, arboreal marsupials, and many different saproxylic species depend on habitat trees and their great variety of microhabitats and old-growth characteristics. With a focus on insights from temperate forests, we traced the development of habitat-tree protection over 200 years. The idea was first conceptualized by foresters and natural scientists in the early 19th century. At that time, utilitarian conservation aimed to protect cavity trees that provided roosts and nesting holes for insectivorous bats and birds. By the second half of the 19th century, habitat-tree protection was well known to foresters and was occasionally implemented. Knowledge of the protection of large old trees, a special kind of habitat tree, for sociocultural and aesthetic reasons developed similarly. But, many foresters of that time and in the following decades fundamentally rejected protection of habitat trees for economic reasons. Beginning in the 1970s, forest conservation and integrative forest management became increasingly important issues worldwide. Since then, the protection of habitat trees has been implemented on a large scale. Long-term views on the development of conservation concepts are important to inform the implementation of conservation today. In particular, historical analyses of conservation concepts allow the testing of long-term conservation outcomes and make it possible to study the resilience of conservation approaches to changing social or ecological conditions. We encourage all conservation ecologists to assess the practical and conceptual impact of the initial ideas that led to modern conservation concepts in terms of long-term biodiversity conservation.  相似文献   
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Augmented Reality uses Head Mounted Displays (HMD) to overlay the real word with additional virtual information. Virtual Retinal Displays (VRD), a new display technology, no longer requires Liquid Crystal Displays (LCD). VRD technology addresses the retina directly with a single laser stream of pixels. There are no studies on the user’s informational strain in this new VRD technology. Various papers have shown that Heart Rate Variability (HRV) is a valid indicator for the user’s informational strain. An empirical test revealed no difference in the user’s HRV between VRD technology and LCD technology. Consequently, there seems to be a comparable user informational strain regarding the display types.  相似文献   
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