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1.
Israeli environmental non-government organizations (ENGOs) are assessed in light of Resource Mobilization Theory, introducing a new method for dividing ENGOs according to strategic orientation. Based on a national survey, 85 groups are categorized as consensus ENGOs that seek understanding aim at finding common grounds, or as conflict ENGOs working “outside the system.” Results show that conflict ENGOs are more grassroots in orientation and consensus ENGOs are more professionalized. Conflict ENGOs operate primarily in local arenas. Consensus ENGOs appear more stable, with larger annual budgets and paid staff, but with fewer registered members. Consensus ENGOs enjoy a wider variety of income sources; receive more funding from government, foreign, and private donations; and have a broader range of self-generated income sources. Conflict ENGOs depend more on membership fees. Both groups are highly dependent on foundation grants. In general, greater resources are associated with consensus activity than among organizations utilizing conflict tactics.  相似文献   

2.
On the equivalence between progressive taxation and inequality reduction   总被引:1,自引:1,他引:0  
We establish the precise connections between progressive taxation and inequality reduction, in a setting where the level of tax revenue to be raised is exogenously fixed and tax schemes are balanced. We show that, in contrast with the traditional literature on taxation, the equivalence between inequality reduction and the combination of progressivity and income order preservation does not always hold in this setting. However, we show that, among rules satisfying consistency and, either revenue continuity, or revenue monotonicity, the equivalence remains intact.  相似文献   

3.
Since the late nineties, stock market investments have become an attractive option for many who want to secure or improve their standard of living, although ?stocks“ are an obscure subject for most of them. They have to rely on investment consultants in banks. Until the stock market crash, there was no reason to complain about the consulting process — shares kept going up in value.But it is remarkable that following the crash, which caused many investors to lose a large amount of money, the relationship between private investors and investment consultants does not seem to have been damaged.In our paper we first show the legal requirements for investment consulting and how these requirements are implemented by banks, and we identify considerable discrepancies between the theoretical and the actual fulfillment of these legal requirements.We then show that it is impossible to meet these requirements in reality because they rely on unrealistic assumptions regarding a consulting process that both adequately covers investment options and addresses the needs of investors. We argue that both sides are more or less satisfied with the situation because they operate on an as if basis: consultant and client talk and behave as if they understood each other.As if the consultant had really informed the client and as if the client had really understood the consultant. This as if which both parties are aware of but which is not openly discussed is the condition of a successful consultancy process and for making the business happen.  相似文献   

4.
The decline of fertility in the course of the Second Demographic Transition is mainly caused by both an increase in childlessness and a decline of large families (three or more births). Which of these effects are stronger in Germany has been contested for a long time. An exact quantification of the particular effects is still missing. In this paper we develop a decomposition method which allows calculating the effects of the particular parity changes between cohort total fertility rates (CTFR) of different cohorts. This method is applied in order to compare German CTFRs for the cohorts the fertility decline occurred in, namely the cohorts between 1933 and 1968. The analyses are differentiated by regions and periods. The CTFR decline can be separated into four components: increasing childlessness, decreasing shares of higher order births (3+), a combined effect and a changing relation of first and second births. In Germany, the effect of the increasing childlessness accounts for 25.9 per cent of the CTFR decline, the decreasing higher order births for 68.0 per cent and the combined effect for 6.1 per cent. The relation of first and second births changed only marginally. Remarkably, these figures are based on two entirely different periods: The CTFR decline between the cohorts of 1933 and 1947 is solely based on the decline of women with three or more children. However, two thirds of the CTFR decline since 1947 is caused by an increasing childlessness. The results are relevant for fertility theories because increasing childlessness and decreasing higher order births have different reasons.  相似文献   

5.
Ligustrum lucidum, a tree native to China has naturalized in Japan where it is often planted in parks and along roads. Naturalized individuals in urban woodlands have uncertain competitiveness against native species, particular in light of the frequent pruning undertaken in these woodlands. We compared fitness-related traits of Ligustrum against two co-occurring native species: a pioneer tree (Mallotus japonicus) and an understory tree (Eurya japonica) under pruned and un-pruned settings. A growth experiments where we assessed the leaf and whole plant characteristics of the 3 species under two environments simulating forest edge and forest interior, and two pruning treatments (with or without) was conducted. Under simulated forest edge without pruning, Ligustrum had lower stem growth and Amax (maximum photosynthetic rate) than Mallotus, suggesting that native species can competitively suppress invasive expansion. With pruning, however, Ligustrum resprouted vigorously in both spring and summer with significantly higher apical growth and total shoots than Mallotus and Eurya in forest edge and interior, respectively. Also, with similar Amax between resprouts of Ligustrum and Mallotus, we see a reversal of competitive advantage in favor of Ligustrum in forest edge. In the forest interior, Ligustrum exhibited shade tolerant properties (i.e., Amax, chlorophyll a/b, and leaf density) similar to Eurya but had more resprout shoots, suggesting that the invader also maintains an advantage under low light. The competitiveness of Ligustrum clearly increased with human disturbance in the form of park pruning. Such management practice can inadvertently enhance the invasiveness of exotic species in urban settings.  相似文献   

6.
We investigated the drivers of street tree transpiration in boreal conditions, in order to better understand tree water use in the context of urban tree planning and stormwater management. Two streets built in Helsinki in 2002, hemiboreal zone that had been planted either with Tilia?×?vulgaris or Alnus glutinosa f. pyramidalis were used as the study sites. Tree water use was measured from sap flow over the 2008–2011 period by the heat dissipation method. Penman-Monteith based evapotranspiration models of increasing complexity were tested against the tree water use measurements to assess the role of environmental and tree related factors in tree transpiration. Alnus and Tilia respectively used 1.1 and 0.8 l of water per m2 of leaf area per day under ample water conditions, but the annual variation was high. The Penman-Monteith evapotranspiration estimate and soil water status changes explained over 80 % of the variation in tree transpiration when the model was parameterized annually. The addition of tree crown surface area in the model improved its accuracy and diminished variation between years and sites. Using single parameterization over all four years instead of annually varying one did not produce reliable estimates of tree transpiration. Tree transpiration, scaled to different canopy cover percentages, implied that the columnar Alnus trees could transpire as much as all annual rainfall at or less than 50 % canopy cover.  相似文献   

7.
Wilkinson and Pickett, in their 2009 book The Spirit Level, found that, in rich countries, income inequality was negatively associated with a range of indicators of well-being, but they did not consider the relationship with volunteering. This paper seeks to fill that gap. Using existing data sources, it shows that, among European countries, higher levels of volunteering are associated with lower levels of income inequality. The relationship is particularly strong for regular and sport-related volunteering. The basic Spirit Level thesis is therefore confirmed as applicable to volunteering. However, while the thesis involves just one theoretical explanation for the income inequality/well-being relationship, namely status anxiety, in the case of volunteering, other variables are also found to be at play, including government social spending, available leisure time and geo-historical traditions. It is concluded that, while high levels of volunteering, as a form of social capital, can be seen as one of a number of features of more equal societies, disentangling cause and effect may require a more holistic approach to understanding its contribution to the generation and sustaining of social well-being.  相似文献   

8.
While decades of academic research have consistently demonstrated a positive relationship between high school employment and adult earnings, the literature is empirically silent in regards to why this association exists. This study uses data from the National Longitudinal Survey of Youth 1997 (NLSY97) to examine the hypothesis that high school employment develops “marketable skills” in the form of occupation-specific human capital. By analyzing wage variation attributable to the commonality of skill portfolios across respondents’ high school and adult (age 20 and 23) occupations, this study fails to find consistent evidence that the types of skills utilized in high school employment are correlated with adult earnings. Within the framework of the human capital model, this would suggest that the positive, post-school economic gains of in-school work are largely attributable to increases in general human capital (e.g., workplace socialization, character building).  相似文献   

9.
We study claims problems in which a certain amount of indivisible units (of an homogeneous good) has to be distributed among a group of agents, when this amount is not enough to fully satisfy agents’ demands. Our aim is to find solutions fulfilling procedural and fairness properties. To do that, we define the M-down methods, which are the unique robust (composition down and consistency) and fair (balancedness and conditional full compensation) rules. Besides, we also establish the relationship between these M-down methods and the constrained equal awards rule.  相似文献   

10.
We analyze markets in which the price of a traded commodity is such that the supply and the demand are unequal. Under standard assumptions, the agents then have single peaked preferences on their consumption or production choices. For such markets, we propose a class of Uniform trade rules each of which determines the volume of trade as the median of total demand, total supply, and an exogenous constant. Then these rules allocate this volume “uniformly” on either side of the market. We evaluate these “trade rules” on the basis of some standard axioms in the literature. We show that they uniquely satisfy Pareto optimality, strategy proofness, no-envy, and an informational simplicity axiom that we introduce. We also analyze the implications of anonymity, renegotiation proofness, and voluntary trade on this domain.  相似文献   

11.
In this paper, we theoretically characterize robust empirically implementable normative criteria for evaluating socially risky situations. Socially risky situations are modeled as distributions, among individuals, of lotteries on a finite set of state-contingent pecuniary consequences. Individuals are assumed to have selfish Von Neumann–Morgenstern preferences for these socially risky situations. We provide empirically implementable criteria that coincide with the unanimity, over a reasonably large class of such individual preferences, of anonymous and Pareto-inclusive Von Neuman Morgenstern social rankings of risks. The implementable criteria can be interpreted as sequential expected poverty dominance. An illustration of the usefulness of the criteria for comparing the exposure to unemployment risk of different segments of the French and US workforce is also provided.  相似文献   

12.
Urbanization is a process that heavily alters marine and terrestrial environments, though terrestrial urban ecosystems have been studied far more intensively. Terrestrial studies suggest that urbanization can facilitate mesopredators by enhancing food and shelter resources and reducing predation pressure from apex consumers. This in turn has considerable consequences for ecological communities. We evaluated spatial distribution patterns and habitat-use of the marine mesopredator, giant Pacific octopus (Enteroctopus dofleini), relative to terrestrial urbanization intensity in Puget Sound, Washington, USA. Using field surveys and citizen-contributed data for E. dofleini, we examined whether: (1) Distribution was related to urbanization, (2) Abundance was related to the extent of benthic anthropogenic debris, and (3) Diet differed as a function of urbanization and den cover. Our results suggest that urbanization impacts may differ with depth. Mixed-effects logistic regression model estimates for the probability of occurrence increased with urbanization in deep-water (> 24 m), and decreased with urbanization in shallow water (< 18 m). Accompanying field surveys indicated that E. dofleini abundance was correlated with the number of benthic anthropogenic debris items, and that E. dofleini diets were not affected by urbanization intensity or den cover. Though E. dofleini may be synanthropic within certain urban environments, the mechanisms driving this pattern likely differ from those affecting common urban mesopredators on land, with den provisioning from man-made structures being more important than altered food resources.  相似文献   

13.
Public debates about the rise in top income shares often focus on the growing dispersion in earnings, and the soaring pay for top executives and financial-sector employees. But can the change in the marginal distribution of earnings on its own explain the rise in top income shares? Are top executives replacing capital owners in the group of top-income earners, or are we rather witnessing a fusion of top capital and top earnings? This paper proposes an extension of the copula framework and uses it for exploring the changing composition of top incomes. It illustrates that changes in top income shares can easily be decomposed into respective changes in the marginal distributions of labour and capital income and the changing association between the two types of income. An application using tax record data from Norway shows that the association between top labour and capital incomes grew stronger between 1995 and 2005 in the top half of the wage and capital income distribution, though it declined for the top 1% of capital income receivers. A gender decomposition demonstrates that the association of wage and capital incomes at the top is particularly striking for men, whilst women are largely under-represented in the top halves of the two marginal distributions.  相似文献   

14.
We analyse the genetic variability in the yellow-necked mouse (Apodemus flavicollis) population in the city of Warsaw, Poland, and its surroundings - a species that has begun to occupy the city only in the last 30 years. We also compare the genetic variability of this species with corresponding data collected in the same time and areas for another species - the striped field mouse (Apodemus agrarius). The results indicate a gradual decrease in genetic diversity and increase in relatedness in the population of A. flavicollis from non-urban locations towards sites with the highest anthropopressure. The genetic structure was more pronounced in the 'recent invader' (A. flavicollis) than in the 'permanent inhabitant' (A. agrarius), which has a much longer city colonization history (more than 100 years). In general, FST was higher in A. flavicollis, which may indicate different and independent ways of city colonization by the species. The process by which urban areas are settled by a new, typically forest-dwelling species such as A. flavicollis, more 'sensitive' to the conditions of life in a city, probably includes not only successful events of penetration of the city by small groups of individuals (the founder effect), but also temporary extinctions of local urban populations of A. flavicollis or at least marked fluctuations in species population numbers. Suitably planned areas at the city borders could play an important role as 'gateways' through which individuals from non-urban populations could migrate into the city and join urban populations.  相似文献   

15.
Modern medicine faces fundamental challenges that various approaches to the philosophy of medicine have tried to address. One of these approaches is based on the ancient concept of phronesis. This paper investigates whether this concept can be used as a moral basis for the challenges facing modern medicine and, in particular, analyses phronesis as it is applied in the works of Pellegrino and Thomasma. It scrutinises some difficulties with a phronesis-based theory, specifically, how it presupposes a moral community of professionals. It is argued that Pellegrino and Thomasma's concept of phronesis corresponds to a Hippocratic concept of téchnê, and that this latter concept seems to address many of the challenging issues Pellegrino and Thomasma also address. Thus, if modern medicine is to find its philosophical model in ancient concepts, it appears that the Hippocratic téchnê is closer to the ancient concept of medicine than the Aristotelian phronesis, and that it might avoid many of the pitfalls of a phronesis-based approach.  相似文献   

16.
Artificial shiny dark objects reflecting horizontally polarized light (e.g. asphalt roads, black cars, solar panels) can attract polarotactic aquatic insects in mass. Glass buildings on the riverside also lure swarming caddisflies emerging from the river. These caddisfly swarms are a temporary rich food source for certain bird species, such as white wagtails (Motacilla alba), house sparrows (Passer domesticus), magpies (Pica pica) and great tits (Parus major). We report here about our observation of great spotted woodpeckers (Dendrocopos major), hooded crows (Corvus cornix) and black redstarts (Phoenicurus ochruros) feeding atypically on Hydropsyche pellucidula caddisflies swarming at glass buildings placed on the shore of the river Danube in Budapest (Hungary).  相似文献   

17.
In urban and suburban ecosystems, biodiversity can depend on various non-native plant species, including crop plants, garden plants and weeds. Non-native plants may help to maintain biodiversity by providing a source of forage for pollinators in these ecosystems. However, the contribution of plants in urban and agricultural areas to ecosystem services has often been underestimated in biodiversity assessments. In this study, we investigated the pollen sources of native honeybees (Apis cerana) in an arboretum containing native trees and urban and agricultural plants in a suburban landscape. We surveyed the flowering tree species planted inside the arboretum, which were potential pollen sources. The number of potential pollen-source species of native trees peaked in June and July and decreased after August. We collected A. cerana pollen balls every month and identified plant species of pollen in the collected pollen balls using DNA barcoding. In total, we identified 29 plant species from A. cerana pollen balls. The probability of A. cerana using pollen from urban and agricultural plants was higher in July and August than in June. A. cerana collected pollen forages from native tree species (53%), but also gathered pollen from crop plants (13%), garden trees (19%) and native and non-native weeds (14%); the predominant pollen sources in September and October were the garden tree Ulmus parvifolia and the non-native weed Solidago altissima. We found that native honeybees used plants from a variety of habitats including non-native plants to compensate for apparent seasonal shortages of native tree sources in suburban ecosystems. Our results highlight the importance of assessments of both positive and negative roles of non-native plants in urbanized ecosystems to improve biodiversity conservation.  相似文献   

18.
Urbanization has been identified as a threat to biodiversity due to landscape modifications. Studies of parasite ecology in urbanized areas lagged behind those made on macro organisms. Here we studied infection prevalence of haemosporidian parasites in an avian community of an urban forest from Germany, and its relationship with bird abundance and body mass. We used PCR to amplify a fragment of the mtDNA cyt b gene to determine the infection status of birds, and bird point counts to determine bird relative abundances. The avifauna was dominated by two small sized insectivore passerines (Parus major, Cyanistes caeruleus), representing ~40 % of the total bird records. The highest haemosporidian prevalence was recorded for Turdus philomelos (100 %) and for Fringilla coelebs (75 %). Bird abundance and body mass were positively associated with infection status for two haemosporidian genera: Plasmodium and Leucocytozoon. Infection rate was lower in juveniles compared to adult birds. We recorded a total of 7 Plasmodium, 26 Haemoproteus, and 10 Leucocytozoon lineages. Avian malaria (P. relictum) was detected infecting 5 individuals of P. major, the most abundant species in the community. These results, together with those of previous studies at the same site, suggest that potentially any of the genetic haemosporidian lineages detected in this urban forest can be transmitted across native and pet bird species, and to species of conservation concern housed at aviaries.  相似文献   

19.
This study is a first attempt to estimate the degree of tritrophic association between the common dandelion Taraxacum officinale complex, the herbivorous weevil Glocianus punctiger and its parasitoid Entedon costalis, as an environmental marker in urban ecosystems. The study was conducted on 3926 dandelion flowering stems spread across 24 sample plots situated within the municipal borders of Kyiv (Ukraine). Eighteen plots were infested by the weevils, and 14 plots were infested by E. costalis. Of all the examined dandelion stems, 359 (9.1 %) were infested by weevils, and 21.4 % of these weevil-infested stems were parasitized by E. costalis. Thirty-two incidents of superparasitism were registered in nine sample plots. Seven environmental variables were chosen for characterization of the sample plots and for testing their possible effects on the tritrophic association. The results indicate that the infestation of dandelions by weevils is strongly limited by the grasslands’ mowing. Apart from that, the presence of anthropogenic barriers bounding the study areas negatively affected the parasitism of G. punctiger by E. costalis. This is regarded as an example of the crucial effect of habitat fragmentation on the specialist herbivore and the specialist parasitoid of this tritrophic system. Both the mowing and habitat fragmentation are linked with human land-use regimes on the sample plots.  相似文献   

20.
Dominant social theories have rarely placed migration at the center of our understanding of society and social change. Classical theories in the Western tradition have been more preoccupied with the impact of economic and political revolutions on social change, stratification and class conflict, and have paid far less attention to other important aspects of society. Contemporary theories have expanded the theoretical gaze to include a much wider set of issues, from racial and gender divisions to warfare and the environment. In an era of globalization, we argue that such a marginalization of the migrant, and the failure to better integrate both internal and external migration into a more nuanced interpretation of social change, is a significant shortcoming. By examining some of the key elements linked to such human movement in Europe, North America and China -- in the light of five recent studies in this field -- we argue that migration is a vital factor in changing the world as we know it and consequently a central concern for social theory. This is a review essay on:Richard Alba and Nancy Foner. Strangers No More: Immigration and the Challenges of Integration in North America and Western Europe. Princeton: Princeton University Press, 2015.Louis DeSipio and Rodolfo de la Garza. US Immigration in the Twenty-First Century: Making Americans, Remaking America. Boulder, CO: Westview Press, 2015.Adrian Favell. Immigration, Integration and Mobility: New Agendas in Migration Studies. Colchester: ECPR Press, 2015.Zhongshan Yue. Social Integration of Rural-Urban Migrants in China: Current Status, Determinants and Consequences. Singapore: World Scientific Publishers, 2015.Robyn R Iredale and Fei Guo. Handbook of Chinese Migration: Identity and Wellbeing. Cheltenham: Edward Elgar Publishing, 2015.  相似文献   

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