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971.
Activity and species-specific responses of insectivorous bats in different urban-forest conditions provides a general perspective on the adaptability and vulnerability of bat species towards urbanization intensity. Here we evaluated species richness and activity patterns of aerial insectivorous bats across an urbanized landscape in the highlands of Chiapas, in Mexico. Acoustic monitoring of echolocation calls was conducted for 27 nights over a period of four months. Species richness and relative activity of insectivorous bats were estimated in a landscape with different conditions of urbanization intensity: urban areas, non-urban and forest areas. We identified a total of 14 bat species and three phonotypes. Bat species richness and relative activity was similar (X2 = 0.568, gl = 2, p > 0.05), but species composition differed among conditions. We observed a significant higher occurrence of Bauerus dubiaquercus, Eptesicus brasiliensis and Myotis californicus in forest sites. Urban sites presented higher occurrence of Molossus rufus and phonotype Molossidae 2, while non-urban sites presented a higher occurrence of Eptesicus furinalis and phonotype Molossidae 2. We were able to identify bat species according to their relative activity in relation todifferent landscape conditions. Species of the Molossidae family presented the highest activity in urban sites, which was positively affected by the number of streetlights, while species of the Vespertilionidae presented the highest activity in forest sites, which was positively related totree density. While urbanization tends to diminish native biodiversity and alter faunal communities, our results show a similar richness and relative activity of aerial insectivorous bats along the urban ecosystem. The effect of urbanization intensity becomes more apparent in species-specific bat activity; the response of species towards particular habitat conditions depends on local habitat quality and characteristics (i.e., presence of streetlights, vegetation cover and tree density).  相似文献   
972.
In sprawling metropolitan areas, residential landscaping is a major concern with respect to biodiversity conservation, and it could play a critical role in conserving wildlife habitat. In the United States, residential landscaping typically consists of maintained lawns with specimen plantings of non-native trees and shrubs; such designs provide poor habitat for urban wildlife species. We conducted a case study of Raleigh, North Carolina residents to determine how providing information about the benefits of native plant landscaping to bird species influenced urban residents’ landscaping preferences. We used Wilcoxon Signed Rank tests to determine if respondent preferences for 0, 50, 75 and 100 % native plant landscaping coverages changed after residents were informed about the benefits that native plants provide for birds. Initially, the 50 % native landscaping coverage was most preferred by residents; however, preferences for all four native plant landscaping coverage designs were significantly different after the informational treatment. Neutrality changed to opposition for the 0 % native plant coverage, while opposition changed to support and neutrality for the 75 and 100 % native plant coverage designs, respectively. After the informational treatment, the 50 and 75 % native plant landscaping coverage had the highest mean preference levels, although the 100 % design was ranked first more than any other design. Our findings suggest that residential support for native plant landscaping is higher than is reflected by typical residential landscaping practices, and that dissemination of information regarding the benefits of native plant landscaping to birds could alter public preferences for native plant landscaping.  相似文献   
973.
Urban afforestation improves life quality in urban centers providing social and environmental benefits. Understanding growth of urban trees exposed to air pollution will support planning, managing and expanding urban areas. This approach intends to determine growth patterns of urban trees to support future urban planning. Non-destructive samples were collected from trees of Araucaria angustifolia (Bertol.) Kuntze in Araucaria city, Parana State, Brazil. Growth rings were related to pollutant concentrations and meteorological series. Growth reduction was observed except in the border areas of the city. Trees established during or after the period of industrialization incentives were most affected by air pollution, indicating that immature plants are more vulnerable. Sulphur dioxide and nitric oxide significantly affected growth of smaller trees. Those greater than 60 cm dbh did not demonstrate significant correlation with any identified pollutant. As the trees established before accentuated urbanization were less affected by air pollution, it is reinforced the importance of preserving remaining urban trees. We suggest that planning urban afforestation should precede industries placing. When urban planning is impossible, new planted trees should not be expected to grow as in free pollution areas, but they will still present satisfactory diameter increment, contributing to improve local urban environment.  相似文献   
974.
Green roofs are emerging engineered ecosystems that provide multiple benefits, but many are constructed with nutrient-rich substrate and have been found to leach out high levels of phosphorus (P) in runoff. It is unclear, however, how long green roofs act as sources of P or what mechanisms are responsible for these net losses. We measured P concentrations in runoff water over 4 years from a 1–5 year old extensive green roof in Cincinnati, OH, USA, produced a model to predict runoff P levels into the future, and validated predictions using runoff from 2 nearby extensive green roofs. P concentrations in runoff from the focal green roof were on par with heavily fertilized agroecosystems and displayed strong seasonal dynamics and a rapid decline over the 4-year study. Runoff measurements and changes in substrate P content over a 2-year period were used to estimate a mass balance for green roof P. P loss from the substrate was substantial (4.55 ± 2.3 g P/m2/yr), but only a small portion of the loss was attributable to leaching of P in runoff (0.19–0.65 g P/m2/yr). Missing P may be attributed to a combination of plant uptake and altered P form and binding strength, but further research is needed to precisely identify the mechanisms of P depletion. Our results also suggest that these and similar extensive green roofs are likely to act as environmentally significant sources of P for 10 or more years following roof installation, highlighting the need for reductions in initial substrate P content.  相似文献   
975.
Objective: To analyze the impact of age, BMI and sex hormone on aging males’ symptoms (AMS) and the 5-item version of the international index of erectile function (IIEF-5) scores in middle-aged and elderly Chinese men.

Methods: A population-based cross-sectional study was conducted in Jiashan County. A total of 969 men, aged between 40 and 80 years old, were admitted. Physical examination and the sex hormones were measured, and AMS and IIEF-5 scores were assessed.

Results: The oneway ANOVA analysis indicated older age groups had higher AMS total-scores, somatic and sexual sub-scores, and lower IIEF5 scores (all p?rpairwise) analyses showed the significant associations between AMS and age or sex hormone (cFT, Bio-T, SHBG, and LH) levels, and similar for IIEF5. However, when age was adjusted, the correlation coefficients (rpartial) weakened, and correlation significance disappeared, except LH (for AMS: rpartial?=?0.096, p?=?.009; for IIEF-5: rpartial?= ?0.140, p?=?.001). Multiple linear regressions confirmed the influence of increased age and LH on the AMS and IIEF5 scores.

Conclusion: CFT, Bio-T and SHBG failed to yield any additional predicting information when age was adjusted. To improve the male reproductive health, future research should pay more attention on aging-related comorbidities and how to improve general wellness.  相似文献   
976.
Measuring the difference between two Gini indexes is important in comparing the inequality between two groups. This paper systematically provides confidence intervals for this difference. First, normal approximation- and bootstrap-based confidence intervals are provided for the difference. Second, empirical likelihood (EL)-based confidence intervals are proposed according to a ratio statistic that is proven to have a weighted Chi-squared distribution with one degree of freedom. Third, two calibration approaches are established to improve the undercoverage issue of the EL method; these two approaches are augmented EL and bootstrap-calibrated EL. Monte Carlo simulations show that bootstrap-calibrated EL generally outperforms other methods in constructing confidence intervals. In the simulations, these methods are compared with the permutation method to test the equality of two Gini indexes. Lastly, these methods are applied to real data.  相似文献   
977.
We examine the relationship between a child’s gender and family expenditure using data from the Polish Household Budget Survey. Having a first-born daughter as compared with a first-born son increases the level of household expenditures on child and adult female clothing, and it reduces spending on games, toys and hobbies. This could be a reflection of a pure gender bias on behalf of the parents or a reflection of gender complementarities between parents’ and children’s expenditures. We find no robust evidence on gender differences in educational investment, measured by kindergarten expenditure. The analysed expenditure patterns suggest a so-far unexamined role of gender in child development. Parents in Poland seem to pay more attention to how girls look and favour boys with respect to activities and play, which could have consequences in adult life and contribute to sustaining gender inequalities and stereotypes.  相似文献   
978.
Early care and education (ECE) enables parental employment and provides a context for child development. Theory suggests that lower child care costs, through subsidized care or the provision of free or low-cost arrangements, would increase the use of ECE and parents’ employment and work hours. This paper reviews the research literature examining the effects of child care costs and availability on parental employment. In general, research suggests that reduced out-of-pocket costs for ECE and increased availability of public ECE increases ECE attendance among young children, and has positive impacts on mothers’ labor force participation and work hours. However, there is considerable heterogeneity in findings. Among U.S. studies that report the elasticity of employment to ECE price, estimates range from ?0.025 to ?1.1, with estimates clustering near 0.05–0.25. This indicates that a 10 % reduction in the price of child care would lead to a 0.25–11 % increase in maternal employment, likely near 0.5–2.5 %. In general, studies using more recent data or data from non-U.S. countries find smaller elasticities than those using U.S. data from the 1990s. These differences may be due to historical and cross-national differences in ECE attendance, labor force attachment, and educational attainment among mothers with young children, as well as heterogeneity in the methodological approaches and data used across studies. More research in the U.S. using contemporary data is needed, particularly given recent changes in U.S. ECE policy.  相似文献   
979.
Previous studies, mostly from Anglo-Saxon countries, find a positive correlation between the presence of young children in the household and self-employment probabilities among women. This has been seen as an indication of women with young children choosing self-employment as a way of balancing work and family commitments. This paper studies the relationship between children and female self-employment in a country with family friendly policies and a generous welfare system: Sweden. The initial hypothesis is that we will not find evidence of a positive effect of children on self-employment among Swedish women since there are other institutions in place aiming at facilitating the combination of work and family. Using Swedish register data for the period 2004–2008 we do, however, find that the presence of young children increases the probability of choosing self-employment also among Swedish women. The effect is strongest for women with very young children, 0–3 years of age. These results also hold in a panel data model that takes individual unobserved heterogeneity into account. We also analyze time-use data and find, contrary to what has been found in many other countries, that self-employed women spend more, or as much, time on market work than wage-earning women. This raises doubts about whether women in Sweden chose self-employment as a way of balancing work and family commitments.  相似文献   
980.
Atkinson’s book Inequality: What Can Be Done? (Harvard University Press, 2015) sets out a range of concrete proposals aimed at reducing income inequality, which cover a very broad span but include major changes to the income tax and social transfers system and the minimum wage. These are framed with specific reference to the UK but have much broader relevance in demonstrating how substantial the impact on inequality of such measures could be. This paper assesses the first-round effects of these tax, transfer and minimum wage reforms on income inequality and poverty based on a microsimulation approach using EUROMOD. The reforms involve a significantly more progressive income tax structure, a major increase in the minimum wage to the level which is estimated to represent the ‘Living Wage’, and alternative routes to reforming social transfers – either to strengthen the social insurance element or to restructure the entire system as a Participation Income (a variant of Basic/Citizen’s Income). The results show how the first-round effects of either set of tax and transfer proposals would be to substantially reduce the extent of income inequality and relative income poverty and the paper draws out how the two approaches differ in their effects. The additional impact of raising the minimum wage to the Living Wage is modest, reflecting in particular the position of beneficiaries in the household income distribution and the offsetting effects on household income of the withdrawal of means-tested cash transfers.  相似文献   
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