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241.
Recent concern over increasing loss of biodiversity has prompted considerable interest in the role of urban green spaces as reservoirs of local biodiversity. This study assessed the diversity of three indicator taxa - plants, ants and birds - on golf courses spanning a wide range of environmental variation in terms of climate, elevation, course age, size and connectivity to native woodland. Species richness and community composition was further compared between contrasting on-course habitat types that reflect different management intensities. We identified a set of taxon-specific environmental correlates indicating an intricate interplay of landscape- and local-scale variables that affect local species diversity. Our results show that floristic diversity is positively associated with the amount of rainfall, whereas ant and bird diversity are related to local-scale factors, particularly the number of trees and the size of water features on a site. The amount of on-course native habitat was a strong predictor of plant and ant diversity and was also associated with the number of unique species at the site level; this reinforces the value of remnant habitat patches as local biodiversity reservoirs that represent mini hot-spots in an otherwise species-poor urban landscape. Community composition for all three taxa differed markedly between non-playing and playing areas, with boundary and remnant habitats generally having more diverse, species-rich communities. Our results suggest that local floral and faunal biodiversity on urban golf courses can be enhanced by creating woody non-playing areas and, especially, by preserving, restoring or expanding remnant habitats.  相似文献   
242.
That “there is no gathering of roses without risking the thorns” might be the simplest way to think of the paradox of relationship. Risk regulation as psychological mechanism minimizes rejection (thorns) and maximizes assurance (roses). In the article, the social psychology of risk regulation is set in the context of divorce and high-conflict parenting. Risk regulation provides not only guidance for treatment, but also a conceptual framework for professional opinion in forensic evaluation and legal consideration.  相似文献   
243.
Urban Ecosystems - Green roofs have recently gained recognition for their potential contribution to urban ecosystems by providing, among other services, habitat for plants and animals, and stepping...  相似文献   
244.
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   
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246.
In the past few years, the Lindley distribution has gained popularity for modeling lifetime data as an alternative to the exponential distribution. This paper provides two new characterizations of the Lindley distribution. The first characterization is based on a relation between left truncated moments and failure rate function. The second characterization is based on a relation between right truncated moments and reversed failure rate function.  相似文献   
247.
It is well known that in finance variances and covariances of asset returns move together over time. Recently, much interest has been aroused by an approach involving the use of the realized covariance (RCOV) matrix constructed from high-frequency returns as the ex-post realization of the covariance matrix of low-frequency returns. For the analysis of dynamics of RCOV matrices, we propose the generalized conditional autoregressive Wishart (GCAW) model. Both the noncentrality matrix and scale matrix of the Wishart distribution are driven by the lagged values of RCOV matrices, and represent two different sources of dynamics, respectively. The GCAW is a generalization of the existing models, and accounts for symmetry and positive definiteness of RCOV matrices without imposing any parametric restriction. Some important properties such as conditional moments, unconditional moments, and stationarity are discussed. Empirical examples including sequences of daily RCOV matrices from the New York Stock Exchange illustrate that our model outperforms the existing models in terms of model fitting and forecasting.  相似文献   
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249.
Who Is to Blame?     
We present the results of a content analysis of communications related to the act of terrorism at Domodedovo airport. They show that mass media plays a significant role as a source of factual, undigested information. The theoretical value of the results is that they show a significant number of cases where an actor is accused with no reference to his actions or nonactions. The range of types of complicity in terrorist activity was substantial.  相似文献   
250.
The perinatal period may not be a happy time for all mothers. During this period, some may develop psychiatric complications, which have both biological and psychosocial etiology, and such illness may affect the whole family. Psychosocial aspects may trigger the illness and act as risk and maintaining factors. Social workers need to intervene in this context for optimal functioning of women with perinatal mental health issues and her family. A biopsychosocial framework may be adopted for social work assessment and intervention. Individual, familial, group, and community level intervention is required to address this complex issue, along with other mental health clinicians.  相似文献   
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