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331.
332.
Spontaneous vegetation colonizes large areas in and around cities. These unmanaged areas are considered to have low economic value or indicate dereliction, but recent research suggests that these can contribute valuable ecosystem services. This study evaluates indicators of ecosystem services in three habitats: urban spontaneous vegetation (USV), managed lawns, and semi-natural urban forest, in Halifax, Nova Scotia. USV had higher indicator values for habitat provisioning (plant species diversity, invertebrate abundance and taxonomic diversity) than the other habitats. Indicators of climatic regulatory services (albedo and leaf area index) in USV were similar to those in lawn habitats. Organic carbon content of the soils, an indicator of carbon storage, was lowest in USV but only marginally lower than in lawns. Standing biomass, an indicator of production services, was lowest in USV but lawn production may have been overestimated. While USV sites are usually transitory components of the urban landscape, they deserve further consideration due to their provision of ecosystem services, in some cases to a greater extent than conventionally valued urban habitats. 相似文献
333.
The literature reports some contradictory results on the degree of phonological specificity of infants’ early lexical representations in the Romance language, French, and Germanic languages. It is not clear whether these discrepancies are because of differences in method, in language characteristics, or in participants’ age. In this study, we examined whether 12‐ and 17‐month‐old French‐speaking infants are able to distinguish well‐pronounced from mispronounced words (one or two features of their initial consonant). To this end, 46 infants participated in a preferential looking experiment in which they were presented with pairs of pictures together with a spoken word well pronounced or mispronounced. The results show that both 12‐ and 17‐month‐old infants look longer at the pictures corresponding to well‐pronounced words than to mispronounced words, but show no difference between the two mispronunciation types. These results suggest that, as early as 12 months, French‐speaking infants, like those exposed to Germanic languages, already possess detailed phonological representations of familiar words. 相似文献
334.
Using In Vitro High‐Throughput Screening Data for Predicting Benzo[k]Fluoranthene Human Health Hazards 下载免费PDF全文
Today there are more than 80,000 chemicals in commerce and the environment. The potential human health risks are unknown for the vast majority of these chemicals as they lack human health risk assessments, toxicity reference values, and risk screening values. We aim to use computational toxicology and quantitative high‐throughput screening (qHTS) technologies to fill these data gaps, and begin to prioritize these chemicals for additional assessment. In this pilot, we demonstrate how we were able to identify that benzo[k]fluoranthene may induce DNA damage and steatosis using qHTS data and two separate adverse outcome pathways (AOPs). We also demonstrate how bootstrap natural spline‐based meta‐regression can be used to integrate data across multiple assay replicates to generate a concentration–response curve. We used this analysis to calculate an in vitro point of departure of 0.751 μM and risk‐specific in vitro concentrations of 0.29 μM and 0.28 μM for 1:1,000 and 1:10,000 risk, respectively, for DNA damage. Based on the available evidence, and considering that only a single HSD17B4 assay is available, we have low overall confidence in the steatosis hazard identification. This case study suggests that coupling qHTS assays with AOPs and ontologies will facilitate hazard identification. Combining this with quantitative evidence integration methods, such as bootstrap meta‐regression, may allow risk assessors to identify points of departure and risk‐specific internal/in vitro concentrations. These results are sufficient to prioritize the chemicals; however, in the longer term we will need to estimate external doses for risk screening purposes, such as through margin of exposure methods. 相似文献
335.
Karen Thorpe Sally Staton Robert Morgan Susan Danby Collette Tayler 《Children & Society》2012,26(4):328-340
The OECD (2006 Starting Strong II: Early Childhood Education and Care. OECD Publishing: Paris) envisions early childhood education and care settings as meeting places for diverse social groups; places that build social capital. This vision was assessed in a comparison of three preschools types: full‐fee paying, subsidised‐fee and publicly funded. The social composition within each was examined and the connectedness of the children (n = 472) who attended compared. Publicly funded preschools had more socially diverse populations. The quantity of social connectedness did not differ but children in publicly funded preschools described higher quality social relationships. Not all preschool settings are socially diverse but, where they are, the quality of relationships is highest. 相似文献
336.
Although they have increased exponentially since the 1960s, social scientists know little about ethnic advocacy organizations. These nonprofits are important bridges between underresourced communities and mainstream funding organizations and their directors are established ethnic leaders. Sociologists study interlocking directorates—or shared board membership—to understand how organizations fit together within broader social networks. Network concepts, particularly the theory of institutional isomorphism, suggest that organizations are likely to be similar to the extent they are connected and operate within a common organizational field. We apply this logic to Latino advocacy organizations to examine the underlying source of cohesion across this ethnic field. We ask whether the organizations are tied by interlocking directorates of ethnic elites who sit on their boards of directors or if board members' common affiliation with other elite institutions creates the structural conditions that facilitate potential ideological or behavioral similarity. A social network analysis of five prominent Latino advocacy organizations reveals support for both hypotheses: Latino board members are both embedded in ethnic‐based networks and entrenched within elite organizational webs. This suggests that ethnic elites who sit on the boards of Latino advocacy organizations are also corporate elites, selected for the social capital they bring to these nonprofits. 相似文献
337.
In this study, we explore how men faculty understand the role of gender in shaping faculty experiences in academic science, technology, engineering and mathematics (STEM) and how they position themselves in relation to inequalities disfavouring women. Our data reveal diversity among men in their understandings regarding challenges facing women in STEM. The majority of our participants revealed gender‐blind perspectives and argued that the egalitarian structure of academia does not allow gender to impact attainments in STEM in any significant way. However, a considerable number of them felt privileged compared to women and described subtle ways in which gender shapes opportunities. Our findings show the important implications of men's sensitivity to gender in the ways they perform their professional roles as, for example, mentors, colleagues and teachers in relation to women in STEM. They further call for attention to men's perceptions of gender issues when designing institutional interventions for improving women's conditions in STEM. 相似文献
338.
Williams Andrew L. 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》2019,30(6):1437-1438
VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - 相似文献
339.
Arcagni Alberto Barbiano di Belgiojoso Elisa Fattore Marco Rimoldi Stefania M. L. 《Social indicators research》2019,141(2):551-579
Social Indicators Research - In this paper, we present a multidimensional fuzzy analysis of the levels and the patterns of poverty and social fragility of migrants’ families, in the Italian... 相似文献
340.
Sarah M. Garrity Sascha L. Longstreth Lisa K. Linder Nina Salcedo Potter 《Children & Society》2019,33(2):168-184
Given their key role in overall programme quality, it is critical to examine how early childhood programme centre directors in the United States perceive challenging behaviour. Participants completed a survey asking which behaviours they perceive to be most problematic, the number of children dismissed or expelled from the programme during the last year, and the most commonly used strategies for addressing challenging behaviours. Results point to several promising practices and highlight the variability in access to evidence‐based practices based on programme type. Areas that warrant more targeted professional development are discussed, and findings are situated within the larger early childhood context. 相似文献