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991.
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   
992.
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   
993.
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   
994.
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   
995.
This paper aims to contribute to the existing studies on the young women’s transition to adulthood in the case of Turkish women’s exclusion from the labour market. The issue is discussed largely within the boundaries of traditional gender restrictions that keep women out of employment. Herein, we argue that the gender-based control of young women, perceived as the reason for their exclusion from the labour market, may be used by disadvantaged women as a way of avoiding difficult and unfavourable employment situations. Similarly, the gender roles imposed on men could also not be fulfilled due to the same restrictive labour market conditions. Furthermore, we suggest that the poverty simultaneously strengthens and erodes the very base of the traditional gender structure for both young women and young men, while forcing the young women out of employment and the young men to the unstable working conditions. This argument is based on a study conducted in Alt?nda?, Ankara with a sample of 279 females and 340 males aged between 15 and 24. A mixed methodology, comprising a survey questionnaire followed by 60 in-depth interviews and 4 focus group discussions, was employed for this study.  相似文献   
996.
997.
The duration of children's attention to putative threat has been documented as a consistent predictor of later anxiety in inhibited children across childhood (Fox, New Directions for Child and Adolescent Development, 127, 2010, 33; Pérez‐Edgar & Fox, Child and Adolescent Psychiatric Clinics of North America, 14, 2005, 681). However, attention to threat has not been broadly examined within existing behavioral contexts and has seldom been studied in very early childhood. Whereas toddlers with high levels of internalizing behavior may view fear‐inducing stimuli as a threat, toddlers with high levels of externalizing behavior may demonstrate attention out of interest or sensation seeking. Thus, attention to threat was expected to predict increased toddler shyness in the context of either high internalizing problems or low externalizing behavior. We examined 117 twenty‐four‐month‐old toddlers to determine whether attention to threat interacted with internalizing and externalizing behavior at 24 months of age to predict toddler shyness one year later. Results indicated that attention to threat predicted toddlers' lower shyness at 36 months when toddlers’ externalizing behavior at age 24 months were high, but there was no significant interaction between toddlers’ internalizing behavior and their attention to threat in predicting later shyness. These results expand our understanding of the contexts in which attention to threat in early childhood is a viable predictor of later shyness.  相似文献   
998.
Previous research has demonstrated that social interactions underlie the development of object‐directed imitation. For example, infants differentially learn object action sequences from a live social partner compared to a social partner over a video monitor; however, what is not well understood is what aspects of social interactions influence social learning. Previous studies have found variable influences of different types of caregiver responsiveness on attention, language, and cognitive development. Therefore, the purpose of this study was to examine how the responsive style of a social partner influenced the learning of object‐directed action sequences. Infants interacted with either a sensitive or redirective experimenter before the learning trial. Results revealed infants changed their patterns of engagement; infants interacting with a sensitive experimenter had longer periods of attentional engagement than infants interacting with a redirective experimenter. Furthermore, during the learning trial, the amount of sensitivity during interaction with the social partner predicted learning scores. These findings suggest that infants' attention is influenced by social partners' interactive style during ongoing interaction, which subsequently affects how infants learn from these social partners.  相似文献   
999.
This study examined the indigenous cultural practices that impact the well-being of children and families at five sites in Nigeria. Fifteen community leaders participated in semi-structured interviews, and 78 community members participated in focus group discussions in their communities. Responses were analyzed using a grounded theory and thematic analysis approach. Three cultural practices are discussed: the naming ceremony of the child, the use of Oríkì, and the care of children and family by relatives. Overall, the cultural practices largely reflected the indigenous knowledge and beliefs of the local context. Implications for social work are discussed.  相似文献   
1000.
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   
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