Seasonal dynamics of bird communities in urban forests of a Mediterranean city (Montpellier,Southern France)

We evaluated the richness, composition and abundance of bird communities in three urban forests of Mediterranean France during winter and spring. The urban forests differed in size, composition, structure, age of vegetation, and location relative to the city centre. Estimated species richness across all three urban forest parks was 45 species. Twenty six (26) species were recorded in both winter and spring, whereas ten species were recorded only in spring, and six were recorded only in winter. Distribution, turnover, and type of bird foraging guild were related to characteristics of each urban forest and season. During spring migration, more species were recorded in sampling units (250?×?250 m) within the largest and most natural urban forest located in the outskirts of Montpellier, whereas during winter, more species were recorded in the most urbanized park (i.e., a botanical garden dominated by exotic vegetation), which was located in the city centre. Insectivorous birds were more abundant in winter, whereas seedeaters associated with wooded habitats were recorded more frequently in spring. Our results suggested that different kinds of urban forests are important modulators of urban bird communities and they are necessary to maintain the diversity of migratory and resident birds as well as increasing the environmental quality of urban areas.     

Testing Hypotheses in the Functional Linear Model

The functional linear model with scalar response is a regression model where the predictor is a random function defined on some compact set of R and the response is scalar. The response is modelled as Y =Ψ( X )+ ɛ , where Ψ is some linear continuous operator defined on the space of square integrable functions and valued in R . The random input X is independent from the noise ɛ . In this paper, we are interested in testing the null hypothesis of no effect, that is, the nullity of Ψ restricted to the Hilbert space generated by the random variable X . We introduce two test statistics based on the norm of the empirical cross-covariance operator of ( X , Y ). The first test statistic relies on a χ ² approximation and we show the asymptotic normality of the second one under appropriate conditions on the covariance operator of X . The test procedures can be applied to check a given relationship between X and Y . The method is illustrated through a simulation study.     

There goes our family friendly neighborhood: Residents’ perceptions of institutionally driven inner-city revitalization in Buffalo,NY

This article examines residents’ perceptions of inner-city revitalization in legacy cities. The analysis focuses on neighborhoods undergoing revitalization in a legacy city, Buffalo, NY. The article draws from data for a larger research project called Turning the Corner which was sponsored by the Urban Institute. The focus of that project was to identify planning strategies to address negative externalities caused by neighborhood change and heightened risks of displacement due to revitalization. Data were collected through a series of focus groups with residents and stakeholders in working-class, minority neighborhoods which were identified as being in the early stages of revitalization. Two findings emerged from the analysis. First, residents perceived urban revitalization to have a destabilizing effect on traditional neighborhoods. Second, residents perceived revitalization as detrimental to the sustainability of family-friendly neighborhoods. Insights from the analysis are used to prompt planners’ advocacy for revitalization strategies aimed at protecting minority, working-class neighborhoods when institutionally driven revitalization occurs.     

On the interaction between heterogeneity and decay in two-way flow models

In this article, we examine the role played by heterogeneity in the popular ??connections model?? of Jackson and Wolinsky (J Econ Theory 71(1):355?C365, 1996). We prove that when heterogeneity with respect to the values of resources, or the information decay parameter, depends on the identity of the player who forms the link, and the player who receives the link, all networks can be supported as Nash. Moreover, we show that Nash networks may not always exist. Interestingly, in the absence of decay, neither result occurs in a model with value heterogeneity. Finally, we show that when reducing heterogeneity, all networks cannot be supported as Nash, and the non-existence problem also disappears.     

Permuted Sample Entropy

Sample entropy (SaEn) was recently developed to quantify the amount of regularity in data. However, the computation of this feature in an online application is infeasible. In this work, we examine a heuristic approach using permuted limited number of samples to estimate SaEn and discuss estimation variability in this context. We conclude that the computation of permuted SaEn provides a fair estimate of time series regularity that can be used in online applications.     

Socially and privately optimal shareholder activism

This paper aims to evaluate the private and social gains of shareholder activism in an optimal contracting framework involving dispersed shareholders who may become active. The social gains are based on the welfare to stake holders in the firm, whereas the private gains are based on shareholder wealth only. Active shareholders influence the contracting game with the CEO, and therefore also the size and the distribution of the surplus to be split between the shareholders and the CEO. Although the model is very simple and focussing on the creation and distribution of welfare between the shareholders and the CEO, we nonetheless identify surprising divergence between the private and social profitability of shareholder activism. Shareholder activism that is privately profitable is not necessarily socially profitable. The distributional effects of shareholder activism may dominate the efficiency effects to make shareholder activism a negative social NPV project.      

Development of the Sexual Five-Facet Mindfulness Questionnaire (FFMQ-S): Validation Among a Community Sample of French-Speaking Women

It has been recently demonstrated that mindfulness-based intervention may be particularly suitable for addressing sexual difficulties in women. Although the Five-Facet Mindfulness Questionnaire (FFMQ) is currently one of the most widely used scales to assess mindfulness, no adaptation and validation of the FFMQ to measure female sexual functioning has been published. The main aim of this study was to develop and validate a sexual version of the Five Facets Mindfulness Questionnaire (FFMQ-S) to specifically measure mindfulness in the context of sexual encounters. A total of 251 healthy, French-speaking female volunteers were administered the FFMQ-S, the original FFMQ, and the Female Sexual Distress Scale (FSDS-R). Confirmatory factor analyses indicated that the FFMQ-S exhibits a five-factor model, as implied by the original FFMQ. Good scale reliability was observed. The FFMQ-S showed significant correlations with the FSDS-R and the usual FFMQ. Scores on the FFMQ-S correlated significantly more negatively with the total FSDS-R score than with the total score of the original version of the FFMQ. These findings clearly support the relevance of developing a version of the FFMQ tailored to sexual functioning.     

FIRM HETEROGENEITY AND THE PATTERN OF R&D COLLABORATIONS

We consider an oligopoly setting in which firms form pairwise collaborative links in research and development with other firms. Each collaboration generates a value that depends on the identity of the firms that collaborate. First, we provide properties satisfied by pairwise equilibrium networks and efficient networks. Second, we use these properties in two types of situation: (1) there are two groups of firms, and the value of a collaboration is higher when firms belong to the same group; (2) some firms have more innovative capabilities than others. These two situations provide clear insights about how firms' heterogeneity affects both equilibrium and efficient networks. We also show that the most valuable collaborative links do not always appear in equilibrium, and a public policy that increases the value of the most valuable links may lead to a loss of social welfare. (JEL C70, L13, L20)     

Nest design in a changing world: Great tit <Emphasis Type="Italic">Parus major</Emphasis> nests from a Mediterranean city environment as a case study

Investigations of urbanization effects on birds have focused mainly on breeding traits expressed after the nest-building stage (e.g. first-egg date, clutch size, breeding success, and offspring characteristics). Urban studies largely ignored how and why the aspects of nest building might be associated with the degree of urbanization. As urban environments are expected to present novel environmental changes relative to rural environments, it is important to evaluate how nest-building behavior is impacted by vegetation modifications associated with urbanization. To examine nest design in a Mediterranean city environment, we allowed urban great tits (Parus major) to breed in nest boxes in areas that differed in local vegetation cover. We found that different measures of nest size or mass were not associated with vegetation cover. In particular, nests located adjacent to streets with lower vegetation cover were not smaller or lighter than nests in parks with higher vegetation cover. Nests adjacent to streets contained more pine needles than nests in parks. In addition, in nests adjacent to streets, nests from boxes attached to pine trees contained more pine needles than nests from boxes attached to other trees. We suggest that urban-related alterations in vegetation cover do not directly impose physical limits on nest size in species that are opportunistic in the selection of nesting material. However, nest composition as reflected in the use of pine needles was clearly affected by habitat type and the planted tree species present, which implies that rapid habitat change impacts nest composition. We do not exclude that urbanization might impact other aspects of nest building behaviour not covered in our study (e.g. costs of searching for nest material), and that the strengths of the associations between urbanization and nest structures might differ among study populations or species.