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941.
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   
942.
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   
943.
A desirable function for terrestrial urban ecosystems is the mitigation of nitrogen (N) pollution associated with cities and suburbs. To assist in maximizing this function, identifying locations of sources and sinks of N in the urban environment is crucial to inform management strategies. Lawns are an extensive land cover in urbanized landscapes, and in general, they have demonstrated the capacity to function as a sink for N inputs. How N is cycled by lawns, however, is likely not uniform across the physical heterogeneity or management activities that exist in lawns. We investigated the influence of heterogeneity in light availability on N cycling in lawns that were irrigated but not fertilized. Light availability is affected by tree canopy and built structures and is, therefore, heterogeneous both within individual lawns and among lawns. Light is expected to control N retention and loss through effects on primary productivity. We experimentally examined N regulation over one calendar year by measuring net primary production (NPP), N retention using an isotopic tracer, and N leaching in existing unfertilized lawns under heterogeneous light conditions. We used a budgetary approach to estimate gaseous N loss which we assume is primarily via denitrification. Light functioned as a limiting resource for primary productivity. From low to high light conditions, annual NPP increased 177 to 430 g C?m?2?y?1 and retention of N isotope tracer increased from 50 to 65% as a result of increased retention in plants. Nitrate leaching losses were low overall and were not affected by light levels. Light availability regulated the fate of N inputs and unfertilized lawns may function as substantial sinks for reactive N through storage in the terrestrial system and N loss by denitrification. However, whether or not denitrification is generally an N sink will depend on the ratio of non-reactive (i.e., N2) to reactive (i.e., N2O, NO) denitrification products. Overall, we find that effective strategies for managing N sources and sinks in cities will likely need to consider light availability, particularly in systems receiving water subsidies via irrigation.  相似文献   
944.
This study’s purpose was to develop a temporal and cultural definition of volunteering in China. Using a comparative mixed-methods approach, N1 = 218 Chinese students in Hong Kong were surveyed about their perceptions of volunteering. These quantitative data were compared cross-culturally with a sample of adults in the United States who used the same instrument called Who is a Volunteer? Subsequently, N2 = 40 of these same students voluntarily participated in a series of focus groups, to further explore more in-depth their opinions about volunteering. The main quantitative results revealed that at the extreme ends of the volunteer scale, both the U.S. and Chinese samples could readily distinguish what volunteering was or was not. The more nuanced empirical differences on the scale (24% of the 21 items) were explained either by unique cultural differences, or the longer and more prominent history that volunteering has had in North America versus China. Main qualitative findings revealed additional between-group cultural differences exemplified by (1) a more family-centric and collectivist Chinese culture versus a more individualistic American culture, (2) a role blurring about volunteer activities versus paid work activities, and (3) that both organizational and cultural context must be seriously considered when defining volunteerism. This study adds to the growing definitional literature on this transformational concept and represents the largest comparative empirical investigation on this subject from East Asia.  相似文献   
945.
We examined first-time fathers’ and mothers’ perspectives about their ideal world of support in the context of dominant social ideology, ethno-cultural ideals, and the pragmatics of their everyday family, workplace, and socioeconomic circumstances during their first 18 months as parents. Twelve Canadian-born and six Chinese immigrant couples participated in individual in-depth interviews. We conducted a three-part analysis: fathers’ perspectives, mothers’ perspectives, and couples’ perspectives. Fathers focused on fulfilling dual fathering ideals of ‘time with family’ and ‘providing for family’; mothers emphasized fulfilling a mothering ideal of ‘caring for children'. Examining couples’ perspectives revealed a more nuanced understanding of their shared focus on ‘caring for family'. Parents in this study found the current social ideal of the ‘new’ father, who is both financial provider and nurturing co-parent, appealing, yet difficult to achieve. Couples wanted informal (i.e. family and social network) support, along with formal (i.e. workplace and childcare) support to enable them to provide family care and financial stability for their family. Findings contribute to understanding family and paid work experiences and decision-making among couples as new parents. We offer insights into the complexity of intersections among social ideals, personal expectations, family care, and paid work for fathers and mothers.  相似文献   
946.
Feminist scholars praise and criticize the UNSC Resolution 1325 on Women, Peace and Security for its considerations of women and gender in conflicts. Poststructuralist feminists show how gender is constructed in the UN’s security policies and how these constructions reproduce gendered dichotomies between women and men and representations of women as victims, part of civil society and neoliberal subjects. Although the UNSC Resolutions 1325 and 1820 are implemented by the EU, there is no literature on how the EU is taking up the UN’s discourse. Scholars studying gender policies in and of the EU mainly analyze the (in)effectiveness of EU gender mainstreaming but rarely interrogate its discursive foundations. Using a governmentality perspective, I argue that on the one hand the EU produces a binary and stereotypical understanding of gender, and on the other hand constitutes women as neoliberal subjects responsible for their own well-being, ignoring broader structures of (gender) inequality and war and making gender equality solely an instrument to achieve more security and development.  相似文献   
947.
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   
948.
Little research has examined the impact of maternal lifetime trauma exposure on infant temperament. We examined associations between maternal trauma history and infant negative affectivity and modification by prenatal cortisol exposure in a sociodemographically diverse sample of mother–infant dyads. During pregnancy, mothers completed measures of lifetime trauma exposure and current stressors. Third‐trimester cortisol output was assessed from maternal hair. When infants were 6 months old, mothers completed the Infant Behavior Questionnaire‐Revised. In analyses that controlled for infant sex and maternal age, education, race/ethnicity, and stress during pregnancy, greater maternal trauma exposure was associated with increased infant distress to limitations and sadness. Higher and lower prenatal cortisol exposure modified the magnitude and direction of association between maternal trauma history and infant rate of recovery from arousal. The association between maternal trauma history and infant distress to limitations was somewhat stronger among infants exposed to higher levels of prenatal cortisol. The analyses suggested that maternal lifetime trauma exposure is associated with several domains of infant negative affectivity independently of maternal stress exposures during pregnancy and that some of these associations may be modified by prenatal cortisol exposure. The findings have implications for understanding the intergenerational impact of trauma exposure on child developmental outcomes.  相似文献   
949.
Infants are readily able to use their recent experience to shape their future behavior. Recent work has confirmed that infants generate neural predictions based on their recent experience (Emberson, Richards, & Aslin, 2015) and that neural predictions trigger visual system activity similar to that elicited by visual stimulation. This study uses behavioral methods to ask, how visual is visual prediction? In Experiment 1, we confirmed that when additional trials provide additional visual experience with the experimental shape, infants exhibit a robust novelty preference. In Experiment 2, we removed the visual stimulus from some trials and presented the predictive auditory cue alone, allowing the effects of neural prediction to be assessed. We found no evidence of looking preferences at test, suggesting that visual prediction does not contribute to the computation of visual familiarity. In Experiment 3, we provided infants with a degraded visual stimulus to test whether visual prediction could bias visual perception under ambiguous conditions. Again, we found no evidence of looking preferences at test, suggesting that visual prediction is not biasing perception of an uncertain stimulus. Overall, our results suggest that visual prediction is not visual, in the strictest sense, despite the presence of visual system activation.  相似文献   
950.
Framed by Relational Dialectics Theory, this study explores the ways adult, former foster children discursively construct meanings of “family.” Contrapuntal analysis of 24 interviews revealed two discourses as competing to constitute family: the Discourse of Family as Irreplaceable and Inescapable (Permanence) and the Discourse of Family as Performative Kinning (Performance). Permanence was constituted by themes of biology and historical connection, reifying normative understandings. Performance, comprised of role enactment, need for tolerance, and unconditional love, challenged the Permanence discourse. Throughout the narratives, Performance competed with Permanence for dominance, illustrating the cultural pervasiveness and power of Permanence yet, in some moments, privileging the marginalized Performance discourse. This discursive competition constructed meanings of family in narratives of life before, during, and after foster care. Overall, participant’s talk constructed complex webs of family relationships, allowing access to an important social institution—family—regardless of the presence/absence of culturally valued markers of family (e.g., biology, legality).  相似文献   
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