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41.
Land-use change has a significant impact on the world’s ecosystems. Changes in the extent and composition of forests, grasslands, wetlands and other ecosystems have large impacts on the provision of ecosystem services, biodiversity conservation and returns to landowners. While the change in private returns to landowners due to land-use change can often be measured, changes in the supply and value of ecosystem services and the provision of biodiversity conservation have been harder to quantify. In this paper we use a spatially explicit integrated modeling tool (InVEST) to quantify the changes in ecosystem services, habitat for biodiversity, and returns to landowners from land-use change in Minnesota from 1992 to 2001. We evaluate the impact of actual land-use change and a suite of alternative land-use change scenarios. We find a lack of concordance in the ranking of baseline and alternative land-use scenarios in terms of generation of private returns to landowners and net social benefits (private returns plus ecosystem service value). Returns to landowners are highest in a scenario with large-scale agricultural expansion. This scenario, however, generated the lowest net social benefits across all scenarios considered because of large losses in stored carbon and negative impacts on water quality. Further, this scenario resulted in the largest decline in habitat quality for general terrestrial biodiversity and forest songbirds. Our results illustrate the importance of taking ecosystem services into account in land-use and land-management decision-making and linking such decisions to incentives that accurately reflect social returns.  相似文献   
42.
Due to land use effects, bioenergy use may cause adverse effects on biodiversity, soil and water and may even fail to guarantee a GHG emissions reduction compared to fossil fuel use. Accounting methodologies and policy instruments were elaborated to prevent these effects, but there is still no sound and consensual methodology to take into account indirect land use change that substantially contributes to GHG emissions as well as a loss of biodiversity. While the iLUC hypothesis, that is the potentiality of adverse effects arising from indirect land use change related to biomass cultivation, is hardly subject to dispute, the quantification of these effects and especially their policy implications are however contentious. Hence, bioenergy policies worldwide face a dilemma: Neglecting iLUC effects that do in fact exist or taking them into account although no sound methodology is available? The article covers the current state of the discussion and also analyses the approaches developed for taking indirect land use change into account. Assessment criteria for coping with the iLUC dilemma are developed and policy recommendations are derived from that.  相似文献   
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44.
Theorizing the Politicizing City   总被引:2,自引:0,他引:2  
This introductory symposium article develops a framework for an urban political reading and a theorization of urban uprisings. We argue that there is a need to foreground the notion of the urban political as central to the theoretical and practical demands of urban research today. First, we revisit critical urban theory in light of recent urban insurrections and point out a lack of sustained theoretical engagement with the political. Second, based on this critique, we argue for what we call a ‘re‐centring of the urban political' to rethink urban theory in ways that consider the city as a site of political encounter, interruption and experimentation, even when, or perhaps especially when, these ways fall outside institutional forms or lack the organizational form or legitimacy of social movements. Thus, we attempt to place politics at the heart of radical urban political theory and practice today in order to make sense of urban subjects, events and claims that elude established government practices and institutionalized structures.  相似文献   
45.
This paper addresses the issue of measuring armed forces’ performance in crisis response operations. By means of interviews (17 respondents) and a large scale survey (1,253 respondents) field and general officers of the Netherlands Armed Forces (NAF) have been questioned on perceived organisational success in crisis response operations. The Dutch officers assess the NAF's performance positively. A number of senior officers are hesitant about the usefulness of measuring the performance of crisis response operations. According to them the context in which the operations are being executed is too complex. Most interviewees, however, are convinced that measuring performance is useful and should be improved. These military leaders express a strong need for criteria to assess their performance on the job.  相似文献   
46.
Since the 1970s technology assessment by public bodies has become generally accepted as necessary. Modes of technology assessment differ from country to country, in terms of degree of institutionalization, acceptance by policy makers and level of public involvement, and these in turn depend on the goals, methods and organizational framework of the particular technology assessment. The varying social and political roles of technology assessment arise out of national political traditions and differing cultural views of technology. This article compares modes of biotechnology assessment in the USA, Japan and Denmark, focusing on the role of public discussion in the policy-making process. By analysing these three different contexts, the article seeks to uncover ways in which the cultural conditioning of technology policy takes place.  相似文献   
47.
Using two newly available ultrahigh-frequency datasets, we investigate empirically how frequently one can sample certain foreign exchange and U.S. Treasury security returns without contaminating estimates of their integrated volatility with market microstructure noise. Using the standard realized volatility estimator, we find that one can sample dollar/euro returns as frequently as once every 15 to 20 s without contaminating estimates of integrated volatility; 10-year Treasury note returns may be sampled as frequently as once every 2 to 3 min on days without U.S. macroeconomic announcements, and as frequently as once every 40 s on announcement days. Using a simple realized kernel estimator, this sampling frequency can be increased to once every 2 to 5 s for dollar/euro returns and to about once every 30 to 40 s for T-note returns. These sampling frequencies, especially in the case of dollar/euro returns, are much higher than those that are generally recommended in the empirical literature on realized volatility in equity markets. The higher sampling frequencies for dollar/euro and T-note returns likely reflect the superior depth and liquidity of these markets.  相似文献   
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49.
The paper refers to legal questions that arise in connection with the collection and use of genetic data in the context of private insurance. The content and meaning of § 18 GenDG is described. Then, § 18 GenDG is set in relation to notification requirements out of the VVG. The paper exemplarily emphasizes that, despite the codification of GenDG, specific legal problems arise. Accordingly, the paper provides solutions to overcome these problems. Particular problems refer to the role of genetic data of third parties and according relations to the family history, possibilities to communicate genetic data by the insured in case of medical indication, the ratio of predictive and diagnostic genetic testing and the range of the total limits of § 18 I 2 GenDG.  相似文献   
50.
This paper reconsiders the effect of investor sentiment on stock prices. Our main contribution is that, in addition to the intermediate term return predictability, we also analyze the immediate price reaction to the publication of survey‐based investor sentiment indicators. We find that the sign of the immediate market response is the same as that of the predictability at intermediate time horizons. This is consistent with underreaction to cash flow news or with investor sentiment being related to mispricing. It is inconsistent with the alternative explanations of a rational response to cash flow news or sentiment indicators providing information about future expected returns.  相似文献   
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