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971.
Aline Canetti Patrícia Póvoa de Mattos Evaldo Muñoz Braz Sylvio Pellico Netto 《Urban Ecosystems》2017,20(5):1057-1068
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
972.
Kevin Constante Michael I. Demidenko Edward D. Huntley Deborah Rivas-Drake Daniel P. Keating Adriene M. Beltz 《Journal of research on adolescence》2023,33(1):24-42
This study examined how ethnic identity relates to large-scale brain networks implicated in social interactions, social cognition, self-definition, and cognitive control. Group Iterative Multiple Model Estimation (GIMME) was used to create sparse, person-specific networks among the default mode and frontoparietal resting-state networks in a diverse sample of 104 youths aged 17–21. Links between neural density (i.e., number of connections within and between these networks) and ethnic identity exploration and resolution were evaluated in the full sample. Ethnic identity resolution was positively related to frontoparietal network density, suggesting that having clarity about one’s ethnic group membership is associated with brain network organization reflecting cognitive control. These findings help fill a critical knowledge gap about the neural underpinnings of ethnic identity. 相似文献
973.
974.
Every state requires a home study before the placement of foster children for adoption. This article examines the history of home studies, presents results from expert interviews on the changing processes and purposes of home studies, and explores current challenges for the field. The article also introduces the Structured Analysis Family Evaluation (SAFE), a uniform home study format that encourages consistent family evaluations across workers, agencies, and jurisdictions. The article clarifies how SAFE may address challenges facing foster care and adoption practice. 相似文献
975.
Using a spatially extensive urban database constructed from the Maryland Biological Stream Survey (MBSS), we describe the
relationships of nutrients in small-order streams to eight defined categories of percent catchment urbanization, correlations
between chloride and conductivity in urban streams, and relationships between nutrients and chloride with two Maryland-specific
indices of biotic integrity for benthic macroinvertebrates and fish assemblages. Stream nutrients become elevated with increasing
percent catchment urbanization, followed by increases in all four measured nitrogen species and total phosphorus at catchment
urbanization levels greater than 10%. There was a strong collinear relationship (r
2 = 0.90) between chloride and conductivity (trimeans) across all eight urbanization classes, where Cl (mg/L) = −0.397 + 0.188*conductivity
(μS/cm). Critical values for all water quality parameters with the two Maryland biological indices were derived using quantile
regression, with significant regressions developed for 11 of 16 water quality parameters and the two biotic indices. For nitrate
(NO3-N), the critical thresholds between fair and poor stream quality for the two Maryland biological indices were 0.83 mg/L (benthic
macroinvertebrate assemblages) and 0.86 mg/L (fish assemblages). Increasing stream nutrient and chloride levels, associated
with widespread catchment urbanization intensity, now affect many small streams in Maryland, with implications for decreasing
water quality in major tributaries and the Chesapeake Bay. 相似文献
976.
977.
Utilizing panel data on families, estimates are made of the effects of children on asset accumulation, asset composition, consumption, and family income. Young children are found to depress savings for young families but to increase savings for marriages of duration greater than five years. The principal channel through which children act to reduce savings is the decline in female earnings associated with the child-induced withdrawal of wives from the labor force. Family consumption actually decreases with the birth of a child, but this reduction is insufficient, for young families, to offset the fall in income. For families in which the wife does not work the estimates suggest that savings may actually increase with children. 相似文献
978.
This study analyzed 1,081 women in Kerala State (India) who were either sterilized or were the wives of sterilized men, and by examining the fertility among a comparable group of 1,000 other women, estimated the number of prevented future births per 1,000 women in the sterilized group. The results of this estimation were then applied to project what the entire savings in births might be over a 3D-year period in the entire Kerala population if each year there were one, three, or five sterilizations performed per 1,000 of total population. The results failed to confirm the hope that the crude birth rate would be decreased by 12 per 1,000 in a decade merely by sterilization of five per 1,000 of the population per annum. The study also discusses various measures of reduction in the crude birth rate. By a reasonable measure, the reduction in the crude birth rate for Kerala from such a sterilization program is estimated as seven points after a decade or nine points after three decades, reflecting decreases of 21 and 36 per cent, respectively, in the number of births. 相似文献
979.
Comparing MCDA Aggregation Methods in Constructing Composite Indicators Using the Shannon-Spearman Measure 总被引:1,自引:0,他引:1
Composite indicators have been increasingly recognized as a useful tool for performance monitoring, benchmarking comparisons and public communication in a wide range of fields. The usefulness of a composite indicator depends heavily on the underlying data aggregation scheme where multiple criteria decision analysis (MCDA) is commonly used. A problem in this application is the determination of an appropriate MCDA aggregation method. Of the many criteria for comparing MCDA methods, the Shannon-Spearman measure (SSM) is one that compares alternative MCDA aggregation methods in constructing composite indicators based on the information loss concept. This paper assesses the effectiveness of the SSM using Monte Carlo approach-based uncertain analysis and variance-based sensitivity analysis techniques. It is found that most of the variation in the SSM arises from the uncertainty in choosing an aggregation method. Therefore, the SSM can be considered as an effective measure for comparing MCDA aggregation methods in constructing composite indicators. We also use the SSM to evaluate five MCDA aggregation methods in constructing composite indicators and present the findings. 相似文献
980.
The present study examined the relationship between relational quality and three different types of jealousy-reactive, anxious and possessive jealousy. The sample consisted of 76 gay men, 79 lesbians, 70 heterosexual women and 70 heterosexual men. Findings show that different types of jealousy affect relationship quality differently and do so differently for homosexuals and heterosexuals. Among heterosexuals and especially gay men--but not among lesbians--anxious jealousy was negatively related to relationship quality. In contrast, among heterosexuals--but not among gay men or lesbians--reactive jealousy was positively related to relationship quality. The present study shows that distinguishing between different types of jealousy is necessary to entangle the diverse effects of jealousy on the quality of homosexual and heterosexual relationships. 相似文献