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51.
It is not clear so far whether alteration of leaf micromorphology and surface wax chemistry due to the impact of environmental factors, such as UV-B radiation, affects retention and rainfastness of applied pesticide solutions. In this study; UV-B treated and untreated adaxial leaf surfaces of apple seedlings (Malus domestica Borkh.) were characterized in terms of chemical composition, micromorphological fine structure, hydrophobicity, and wettability. Furthermore, the retention and rainfastness of applied fungicide mancozeb were studied. The samples were examined 0, 24 and 48 h after ultraviolet (UV)-B radiation (0.022 kW m(-2) for 150 min) The total wax mass, recovered from the adaxial leaf surface, amounted from 0.38 microg cm(-2) (control) up to 0.49 microg cm(-2) (24 h). Chemical composition of surface wax altered, whereas the contact angle of applied water droplets on leaf surface of UV-B treated plants did not change significantly compared to the control. The alteration of surface wax quantity and quality significantly affected retention of a.i.; it increased at a sampling time of 24 h after UV-B irradiation, whereas rainfastness of the fungicide spray solution was not significantly influenced.  相似文献   
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Policy-makers are increasingly recognising that the promotion of more sustainable consumption patterns is an indispensable prerequisite for achieving sustainable development in the long term. Policy documents and action plans have been published, and a wide array of policy instruments has been implemented with the aim of reducing the environmental and social burdens of consuming goods and services. But what are the latest trends and innovative approaches in sustainable consumption (SC) policies? What could be learnt for future policy-making? Based on an overview of European policy instruments and several case studies, the paper discusses instructive examples of SC policy instruments, in particular the Danish information campaign "One Tonne Less", the Dutch tax incentive scheme "Green Funds", the British "Red/Green calculator", and the pan-European internet platform "TopTen". Important features of novel policies — such as adaptability and collective action — are identified, and recommendations for future policies are presented. The recommendations refer to the foundation of SC policies, to the specific approach taken, to the applied instruments, and to the proper documentation of the implemented policies.  相似文献   
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ABSTRACT

Achieving sustainable consumption and production requires a break with current practices in many sectors, including the smartphone sector. Leaders are central actors in catalysing such change by developing, implementing and promoting innovative ideas, products and practices. Not only large but also small enterprises can aspire to assume leadership for sustainability. This contribution explores the environmental, climate and social leadership of the social enterprise Fairphone that seeks to start a movement towards a more sustainable smartphone sector. Endowed with barely any structural power, it relies on other leadership types, especially entrepreneurial leadership, which is based on dialogue, persuasion and coalition-building. Small enterprises can be leaders, but pursuing a goal such as transforming the smartphone sector takes a step-by-step approach targeting different follower groups from suppliers, competitors and consumers to end-of-life processors and policymakers. Those different follower groups are susceptible to different (combinations of) leadership types.  相似文献   
54.
Kessler A  Halitschke R  Poveda K 《Ecology》2011,92(9):1769-1780
Although induced plant responses to herbivory are well studied as mechanisms of resistance, how induction shapes community interactions and ultimately plant fitness is still relatively unknown. Using a wild tomato, Solanum peruvianum, native to the Peruvian Andes, we evaluated the disruption of pollination as a potential ecological cost of induced responses. More specifically, we tested the hypothesis that metabolic changes in herbivore-attacked plants, such as the herbivore-induced emission of volatile organic compounds (VOCs), alter pollinator behavior and consequentially affect plant fitness. We conducted a series of manipulative field experiments to evaluate the role of herbivore-induced vegetative and floral VOC emissions as mechanisms by which herbivory affects pollinator behavior. In field surveys and bioassays in the plants' native habitat, we found that real and simulated herbivory (methyl jasmonate application) reduced attractiveness of S. peruvianum flowers to their native pollinators. We show that reduced pollinator preference, not resource limitation due to leaf tissue removal, resulted in reduced seed set. Solitary bee pollinators use floral plant volatiles, emitted in response to herbivory or methyl jasmonate treatment, as cues to avoid inflorescences on damaged plants. This herbivory-induced pollinator limitation can be viewed as a general cost of induced plant responses as well as a specific cost of herbivory-induced volatile emission.  相似文献   
55.

Objective

To report uptake of genetic counseling (GC) and prenatal genetic testing after the finding of atypical genitalia on prenatal ultrasound (US) and the clinical and genetic findings of these pregnancies.

Methods

A retrospective cohort study (2017–2019) of atypical fetal genitalia in a large expert center for disorders/differences of sex development. We describe counseling aspects, invasive prenatal testing, genetic and clinical outcome of fetuses apparently without [group 1, n = 22 (38%)] or with [group 2, n = 36 (62%)] additional anomalies on US.

Results

In group 1, 86% of parents opted for GC versus 72% in group 2, and respectively 58% and 15% of these parents refrained from invasive testing. Atypical genitalia were postnatally confirmed in 91% (group 1) and 64% (group 2), indicating a high rate of false positive US diagnosis of ambiguous genitalia. Four genetic diagnoses were established in group 1 (18%) and 10 in group 2 (28%). The total genetic diagnostic yield was 24%. No terminations of pregnancy occurred in group 1.

Conclusions

For optimal care, referral for an expert fetal US scan, GC and invasive diagnostics including broad testing should be offered after prenatal detection of isolated atypical genitalia.  相似文献   
56.
Environmental Modeling & Assessment - To build a forecasting tool for the state of eutrophication in the Archipelago Sea, we fitted a Generalized Additive Mixed Model (GAMM) to marine...  相似文献   
57.

Future developments of the Bulgarian economy, energy demand, energy supply, and greenhouse gas (GHG) emissions are projected and evaluated for baseline and mitigation scenarios. Different methods and approaches are used at different stages of the study with a tendency to incorporate them in a single integrated resource planning tool such as the MARKAL-MACRO model. The results obtained indicate that the aim of Framework Convention of Climate Change to have year 2000 GHG emissions below the base year 1988 emissions will be achieved without further mitigation steps. Reducing the expected increase of GHG emissions in the decade 2000 to 2010 requires a package of mitigation measures to be implemented in the next few years.

  相似文献   
58.
Storm surges: perspectives and options   总被引:4,自引:1,他引:3  
This review paper attempts to summarize the scattered and fragmented knowledge about past and possible future changing storm-surge statistics using the particularly well-studied case of the North Sea as an example. For this region, a complete and robust analysis methodology has been developed in recent years. This methodology is based on dynamical and statistical models. Using the concept of dynamical downscaling, development during recent decades, when sufficiently good and homogeneous weather data exist, has been “reconstructed,” and scenarios of possible future change are described. “Localization” allows estimation of changes at specific sites, e.g., harbors. As local water-level statistics depend not only on climate variations but also on local modifications of the local bathymetry, new options for adaptation emerge. For the case of Hamburg, an option for such future adaptations is discussed.  相似文献   
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