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291.
Markus Salomon 《Environmental Sciences Europe》2007,19(3):155-167
On 26 April this year the German Environmental Advisory Council (SRU) published a statement on ‘Pharmaceuticals in the environment’ and pointed considerable need for action to understand and to reduce the risks from diffuse pharmaceutical inputs in the environment. On the one hand, it is urgently necessary to improve the database for environmental risk assessments; on the other hand measures should already be taken to minimize harmful inputs. Fortunately, the new regulations for an application for an authorization to market new pharmaceuticals require an environmental risk assessment. However, there is a lack of information on possible impacts from long time admitted medicines which may be responsible for harmful active substances detectable in the environment. To remove this data deficit, a European programme for risk evaluation of old pharmaceuticals should be established. It is necessary for an adequate risk assessment to look at all impacts of one active substance or all substances same-directed in their active potential summativ and to generate regularly consumption data in particular for the use of veterinary products. The hot spots of contamination are the introduction of large scale volumes of active pharmaceutical ingredients for human use like diclofenac and carbamazepin as well as hormones into surface waters, as well as the application of antibiotics-loaded economic fertilizers on soils. Not to be neglected is the application of antiparasitics in animals kept on pasture. With the assessment of the use of pharmaceuticals for all purposes special attention is needed on antibiotic resistance. For the mitigation of environmental exposures there are exposures measures necessary to reduce use of antibiotics in farming, for the application of new effective technologies in treatment sewage — as for example ozonation, filtration with activated carbon or membrane filtration — as well as for the labelling of environmentally harmful medicinal products. 相似文献
292.
Algae are continuously exposed to short-term fluctuations in irradiance. We investigate how two red algae species regulate photosynthetic efficiency to cope with such changes and identify some strategies that differ from higher plants. Two red algae, Gracilaria domingensis and Kappaphycus alvarezii, with antheraxanthin and lutein as major xanthophylls, respectively, reacted to the onset of low light (below E
k) with a substantial decrease of NPQ. This is different from higher plants, but similar to previous observations in, e.g. cyanobacteria where it indicates an increase in the effective absorbance cross-section of Photosystem II (PSII) by state transition. Kinetic studies in continuous light revealed a high susceptibility of PSII to light stress ((1-q
P)/NPQ) in K. alvarezii immediately after the sudden onset of high light, followed by a decrease. This was caused by a slower onset of NPQ in K. alvarezii, followed by acclimation. In G. domingensis, susceptibility of PSII to light stress was stable with time, but absolute values of (1-q
P)/NPQ were higher than in K. alvarezii. These observations suggest that K. alvarezii may be better adapted to high light levels, but is less well prepared for large sudden changes in irradiation. In K. alvarezii, photosynthesis continued to increase with increasing irradiation when NPQ was saturated. As (1-q
P) and NPQ were still balanced in this situation, most likely, processes other than photosynthetic oxygen release are responsible for the increasing net O2 production observed. 相似文献
293.
Lukkari T Taavitsainen M Soimasuo M Oikari A Haimi J 《Environmental pollution (Barking, Essex : 1987)》2004,129(3):377-386
Biomarkers in the earthworm Aporrectodea tuberculata (Eisen) were measured to find out their possible induction under Cu and Zn exposure and differences in the responses between two populations with different exposure history. The biomarkers applied were concentration of metallothioneins (MT), and cytochrome P4501A (CYP1A) monooxygenase and glutathione-S-transferase (GST) activities. These were measured from earthworms sampled at three distances from a steel smelter in Finland and from the individuals from two populations, one with and another without earlier metal exposure, exposed to three combined Cu/Zn concentrations in the laboratory. In the field, MT concentration, and cytochrome CYP1A and GST activities decreased with increasing distance from the smelter. In the laboratory, biomarker responses varied in relation to the duration and level of exposure, and they were also dependent on the population. The endpoints appeared to be analytically reproducible and sensitive parameters in A. tuberculata, and thus, they can be used in ecotoxicological field monitoring and in experimental research in the laboratory. 相似文献
294.
A study of the water-mass circulation of the Baltic has been undertaken by making use of a three dimensional Baltic Sea model simulation. The saline water from the North Atlantic is traced through the Danish Sounds into the Baltic where it upwells and mixes with the fresh water inflow from the rivers forming a Baltic haline conveyor belt. The mixing of the saline water from the Great Belt and Oresund with the fresh water is investigated making use of overturning stream functions and Lagrangian trajectories. The overturning stream function was calculated as a function of four different vertical coordinates (depth, salinity, temperature and density) in order to understand the path of the water and where it upwells and mixes. Evidence of a fictive depth overturning cell similar to the Deacon Cell in the Southern Ocean was found in the Baltic proper corresponding to the gyre circulation around Gotland, which vanishes when the overturning stream function is projected on density layers. A Lagrangian trajectory study was performed to obtain a better view of the circulation and mixing of the saline and fresh waters. The residence time of the water masses in the Baltic is calculated to be 26-29 years and the Lagrangian dispersion reaches basin saturation after 5 years. 相似文献
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298.
Ari Jokinen Helena Leino Pia Bäcklund Markus Laine 《Journal of Environmental Policy & Planning》2018,20(5):551-563
The aim of our article is to follow how global policy models affect local policy making. Each city has unique local challenges in promoting development, e.g. economic growth, but also needs to find a balance between these targets and demands for sustainable city solutions. In our empirical study, we follow how ideas of waterfront development – to attract new inhabitants and promote economic growth – and global demands of carbon control were used interactively in a strategic spatial planning process in the city of Tampere, Finland. During the six-year planning process, these two policy targets became interdependent, created a new policy-making domain, and led to a combinatorial development of sustainability elements arising from this domain. These findings demonstrate the serial use of global policy models in the creation of a local urban ‘sustainability fix’. To conclude, the intertwinement of diverse global policy models in a city planning process creates easily a recursive cycle that redefines urban sustainability within cities and intercity networks. This perspective makes local policy narratives and strategic planning highly important in urban sustainability research as promoting urban sustainability becomes an inherently ambivalent practice. 相似文献
299.
Michael J. Liles Markus J. Peterson Yvonna S. Lincoln Jeffrey A. Seminoff Alexander R. Gaos Tarla Rai Peterson 《Local Environment》2015,20(11):1383-1404
Hawksbill turtles (Eretmochelys imbricata) are highly endangered in the eastern Pacific Ocean, yet their eggs continue to be an important subsistence resource for impoverished coastal residents in El Salvador. In this study, we use naturalistic inquiry to explain the realities experienced by coastal residents who share habitat with hawksbills in El Salvador, and then suggest implications of the disparities between these realities and international priorities for hawksbill conservation and community development in El Salvador and other low-income regions. To provide a context for understanding hawksbill conservation and its implications for similar challenges related to conservation and wellbeing, we first summarise the conservation context, including the emergence of sea turtle conservation in El Salvador. We then describe our naturalistic approach, including the ethnographic methodology for this study. Finally, we detail the analysis of interviews conducted with tortugueros (i.e. local sea turtle egg collectors), to help explain how hawksbills fit into local realities. Our results demonstrate that, from the perspective of tortugueros, (1) the primary importance of hawksbills is the economic value attached to egg sales, but there exists a deeper connection to local culture; (2) egg purchase by hatcheries is a socially just conservation strategy that benefits both hawksbill and human wellbeing; and (3) opportunities for local residents to participate in decision-making regarding sea turtle conservation are limited, and should be increased. We argue that harmonising international conservation priorities with local community development realities is one path towards simultaneously contributing to long-term sea turtle recovery and human wellbeing in low-income regions. 相似文献
300.
Albrecht M 《Die Naturwissenschaften》2007,94(12):951-966
This review gives an introduction into supramolecular chemistry describing in the first part general principles, focusing on terms like noncovalent interaction, molecular recognition, self-assembly, and supramolecular function. In the second part those will be illustrated by simple examples from our laboratories. Supramolecular chemistry is the science that bridges the gap between the world of molecules and nanotechnology. In supramolecular chemistry noncovalent interactions occur between molecular building blocks, which by molecular recognition and self-assembly form (functional) supramolecular entities. It is also termed the "chemistry of the noncovalent bond." Molecular recognition is based on geometrical complementarity based on the "key-and-lock" principle with nonshape-dependent effects, e.g., solvatization, being also highly influential. Self-assembly leads to the formation of well-defined aggregates. Hereby the overall structure of the target ensemble is controlled by the symmetry features of the certain building blocks. Finally, the aggregates can possess special properties or supramolecular functions, which are only found in the ensemble but not in the participating molecules. This review gives an introduction on supramolecular chemistry and illustrates the fundamental principles by recent examples from our group. 相似文献