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971.
The goal of this study was to advance understanding of how adolescent conflict appraisals contribute uniquely, and in combination with interparental conflict behavior, to individual differences in adolescent physiological reactivity. Saliva samples were collected from 153 adolescents (52% female; ages 10–17 years) before and after the Trier Social Stress Test. Saliva was assayed for cortisol and alpha‐amylase. Results revealed interactive effects between marital conflict and conflict appraisals. For youth who appraised parental conflict negatively (particularly as threatening), negative marital conflict predicted dampened reactivity; for youth who appraised parental conflict less negatively, negative marital conflict predicted heightened reactivity. These findings support the notion that the family context and youth appraisals of family relationships are linked with individual differences in biological sensitivity to context.  相似文献   
972.
This study investigates short‐term and long‐term associations between parenting in early adolescence and delinquency throughout adolescence using data from the National Longitudinal Surveys. Multilevel longitudinal Poisson regressions show that behavioral control, psychological control, and decision‐making autonomy in early adolescence (ages 10–11) are associated with delinquency trajectories throughout adolescence (ages 10–17). Path analyses reveal support for three mediation hypotheses. Parental monitoring (behavioral control) is negatively associated with delinquency in the short term and operates partly through changes in self‐control. Parental pressure (psychological control) shows immediate and long‐lasting associations with delinquency through changes in self‐control and delinquent peer pressures. Decision‐making autonomy is negatively associated with delinquency in the long term, yet may exacerbate delinquency in early adolescence by increasing exposure to delinquent peers.  相似文献   
973.
ABSTRACT

Numerous mental health disorders plague our veterans when they return from deployment including anxiety and depressive disorders, which have been linked to elevated suicide risk when left untreated. Family factors, such as parenthood status, may serve as a protective factor against these mental health issues. This study examined the role of parenthood status of male veterans (N = 234) based on age of the child in order to determine whether a child’s age (minor children v. adult children) affects the likelihood of meeting diagnosis criteria for anxiety, depression, and suicide ideation after controlling for marital status. Three hierarchical binary logistic regression models were constructed to assess the predictive influence of children 18 years old and younger, children older than 18, and no children with the results indicating that parenthood status did meaningfully enhance the prediction of suicide ideation. Complete findings, clinical implications, and future considerations are discussed.  相似文献   
974.
This study explores the conversion of cultural capital into economic capital, and specifically financial capital in the form of parental financial planning for children’s college education, including reported financial preparations and savings. Using data from the Education Longitudinal Study (ELS:2002), logistic regression-based analyses of aspects of cultural capital indicated that parental involvement exhibited the most prevalent relationship with financial planning and the amount saved, and that parents’ expectations, but not their aspirations, corresponded to engagement in financial planning. Findings support the conclusion that some parents convert part of their cultural capital to financial capital in preparation for paying for their child’s college education, perhaps representing a typically hidden facet of social class reproduction.  相似文献   
975.
Financial capability—financial knowledge, skills, and access to financial services—may help smooth transitions to adulthood for youth and is affected by socialization experiences with parents and other family members. Among a sample of youth and their parents enrolled in the YouthSave experiment in Ghana (n?=?4,065), this study examined whether physical access to financial services and/or visiting banks with parents or other family members was associated with youth’s perceptions and understanding of financial institutions. We found a statistically significant association between visiting the bank with a parent or other family member and youth’s attitudes (β?=?1.45, p?<?0.001) and understanding of financial services (β?=?2.96, p?<?0.001), controlling for other factors like household income and assets. Conversely, physical access (distance, travel time) was not associated with financial services attitudes or understanding. Parents may play an important role in introducing their children to financial services. Practitioners and policy makers should consider ways to include parents in efforts to promote financial capability among youth.  相似文献   
976.
Urban forests provide valuable ecosystem services, but their long-term viability is often threatened by low tree recruitment due to seed and/or microsite limitation. Distinguishing between these two causes of low recruitment has important management implications, but has been little studied in urban environments. We tested for seed and microsite limitation in an urban forested park in Seattle, Washington, USA by adding conifer tree seeds and seedlings to experimental plots in which we manipulated microsite conditions by removing invasive ivy (Hedera spp.) and adding deadwood. We found that natural seed production was low, and adding seeds increased the number of observed seedlings. Furthermore, adding deadwood increased seedling survival, whereas removing Hedera did not have strong effects. Seed limitation is frequently addressed through management actions such as sowing seeds and transplanting seedlings, and our results suggest that such actions address a critical barrier to tree recruitment in urban forests. However, we also observed strong microsite limitation. At our study site, microsite limitation can be addressed primarily by adding deadwood and retaining coarse woody debris on site. Addressing microsite limitation may be a critical component of successful management efforts to improve tree recruitment in urban forests, and should not be overlooked. Furthermore, our study highlights the need for active monitoring and data analysis alongside management, since the most apparent threat (widespread cover of an invasive plant in this case) may not be the primary limit on suitable microsite conditions.  相似文献   
977.
Due to habitat fragmentation, resource disruption and pollution, urbanization is one of the most destructive forms of anthropization affecting ecosystems worldwide. Generally, human-mediated perturbations dramatically alter species diversity in urban sites compared to the surroundings, thus influencing the functioning of the entire ecosystem. We investigated the taxonomic and functional diversity patterns of the aquatic macroinvertebrate communities in tank bromeliads by comparing those found in a small Neotropical city with those from an adjacent rural site. Changes in the quality of detrital inputs in relation to lower tree diversity and the presence of synanthropic species are likely important driving forces behind the observed structural changes in the urban site. Leaf-litter processors (i.e., shredders, scrapers) were positively affected in the urban site, while filter-feeders that process smaller particles produced by the activity of the shredders were negatively affected. Because we cannot ascertain whether the decline in filter-feeders is related to food web-mediated effects or to competitive exclusion (Aedes aegypti mosquitoes were present in urban bromeliads only), further studies are necessary to account for the effects of intra-guild competition or inter-guild facilitation.  相似文献   
978.
Urban areas are understood to be extraordinarily spatially heterogeneous. Spatial heterogeneity, and its causes, consequences, and changes, are central to ecological science. The social sciences and urban design and planning professions also include spatial heterogeneity as a key concern. However, urban ecology, as a pursuit that integrates across these disciplines, lacks a theoretical framework that synthesizes the diverse and important aspects of heterogeneity. This paper presents the concept of dynamic heterogeneity as a tool to explore how social and ecological heterogeneities interact and how they together act as both an outcome of past interactions and a driver future heterogeneity and system functions. To accomplish this goal, we relate heterogeneity to the fundamental concept of the human ecosystem. The human ecosystem concept identifies key processes that require operationalized models of dynamic heterogeneity in three process realms: the flow of materials, the assembly of urban ecosystem biota, and the locational choices humans make concerning land. We exemplify a specific dynamic model of heterogeneity in each of these realms, and indicate a range of complementary statistical approaches to integrate the drivers and outcomes of dynamic heterogeneity across the three realms. We synthesize a hierarchical framework for a theory of dynamic urban heterogeneity, noting its complementarity to other major urban theories and general model approaches. We hypothesize that human actions and structures amplify the dynamics of heterogeneity in urban systems.  相似文献   
979.
With a growing number of people living in urban areas, city residents are more frequently exposed to stresses related to the built environment including elevated summer surface temperatures contributing to the urban heat island (UHI) effect. This study examines the role of urban tree density in moderating surface temperature variation in a densely populated city (Toronto, Canada). By applying parallel aspatial (OLS) and spatial regression (GWR) approaches with satellite derived data describing tree canopy density and surface temperature, one dimension of tree canopy quality (i.e., canopy density) is shown to contribute directly to a reduction in the surface urban heat island (SUHI) effect at a local scale. Though the model fit differed between the two regression approaches, both exhibited moderately strong explanatory power and demonstrated that observed surface temperature decreases in locations with increasing high-density and closed tree canopy. Study findings provide an empirical basis to recommend that municipal urban forest strategies embrace canopy quality metrics, such as increasing the density of existing urban forest stands, as a part of tree planting objectives seeking to effectively deliver temperature moderation as a valuable ecosystem service.  相似文献   
980.
The objective of this study was to evaluate the relative effects of watershed land-use on streambed substrate composition in eight low-order tropical streams. Data were collected at 24 sampling sites for eight wadeable streams in the Pirapó River Basin, southern Brazil. According to the percentage of impervious surfaces in the watershed, we defined the streams as either urban or rural. We estimate the percentages of the different streambed substrates, hydrological variables, and the rainfall intensity. The results showed that silt, sand and coarse particulate organic matter (CPOM) contributed to significant differences in streambed substrate composition between urban and rural streams. Silt, sand and CPOM were found in a higher mean proportion in the rural streams. Probably the urban streams have a greater bed load, promoted by precipitation and discharge, than rural streams, especially fine sediment. Rural streams have soft hydrographs, with stream flow slowly increasing during a rainstorm and subsequently decreasing over a long period after the rain event is over. These characteristics can provide the lixiviation of fine sediments into the stream channels due to land-surface clearance for agricultural activities and their accumulation in the streambed due to the moderate discharge regime.  相似文献   
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