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941.
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
942.
ABSTRACTResearchers often approach employers to investigate employees’ work and family experiences. Organizational willingness to grant access to employees can vary, especially when the research topic is seen as controversial or contentious for the employer. This paper explores this methodological challenge using a research example from Manitoba, Canada, which explored the use of parental leave by male employees and the impact of managerial attitudes and corporate culture on usage. Sixty large employers were recruited with only seven of those organizations agreeing to participate. In this paper, the reasons organizations gave for declining to participate and the implications of their decisions for the research are examined. Although the final sample included 905 managers and employees, participating organizations tended to be employee-focused and family-friendly employers. Organizations declined participation for a variety of reasons: avoiding raising the issue with unions, awareness that their policies unfairly benefited female leave takers, and simply not seeing the relevance of a topic relating to men’s work–family experiences. A dialogue often absent from the literature, it is important to understand how employers can limit researchers’ access to employees on controversial topics. The existence of such barriers suggests alternative avenues to recruit participants directly when topics are contentious for employers. 相似文献
943.
This article analyzes the social construction of border surveillance and policing in reality-based television. Utilizing content analytic methods to document and decode popular images of borders, mobility, and insecurity, it assesses three programs from Australia, the UK, and the United States. Despite claims of offering accurate and unfiltered depictions, the programs are ideological and provide visions of enforcement that reinforce stereotypes regarding the risks of permeable borders and exonerate intensive regimes of surveillance and securitization. Our findings suggest this occurs in three ways. First, the programs inflate the extent and seriousness of lawlessness associated with cross-border movement. Second, they offer individualistic explanations of crime that cite personal choices and pathologies as determinants. Finally, alongside neglecting their perspectives and interpretations of events, when compared to the reality of official statistics, the programs disproportionately feature suspected offenders as members of marginalized groups. The social and political implications of these findings are discussed. 相似文献
944.
Peter Van Aelst Patrick van Erkel Evelien D’heer Raymond A. Harder 《Information, Communication & Society》2017,20(5):715-732
Attention in the mass media is seen as crucial for electoral success. However, most ordinary candidates hardly get any attention in the news. With social media outlets becoming ever more popular, the question is whether the overall asymmetry in attention for candidates still holds today. Do candidates who dominate the traditional media during the campaign also dominate the social media? Or can candidates make up for a lack of mass media coverage by attracting attention on these new media platforms? This paper aims to answer these questions by pairing Twitter activity and Twitter popularity with newspaper attention for a large number of individual candidates in the 2014 Belgian election campaign. We expand the normalization versus equalization debate by not only looking at how much a new medium is used, but also at its success in terms of popularity and audience reach. Our findings show that the two platforms are indeed related, mainly because a small political elite dominates both old and new media. Twitter popularity and Twitter activity (albeit to a lesser extent) are higher among powerful politicians. We elaborate on why these findings are so much in line with the normalization hypothesis. 相似文献
945.
Michelle Bosquet Enlow Katrina L. Devick Kelly J. Brunst Lianna R. Lipton Brent A. Coull Rosalind J. Wright 《Infancy》2017,22(4):492-513
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
946.
Lindsey J. Thomas Jennifer A. Jackl Jenny L. Crowley 《Journal of Family Communication》2017,17(3):238-253
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
947.
948.
Samantha M. Hack Christopher R. Larrison Melanie E. Bennett Elizabeth A. Klingaman Amanda D. Peeples 《Social Work in Mental Health》2017,15(1):99-120
Semi-structured qualitative interviews were conducted with 26 African American men with serious mental illness who were consumers of community mental health services and 26 members of their social support networks. All participants were asked what they believed had caused the consumers’ mental illness. Consumer participants most commonly identified chronic life stressors as a causal factor, while social supports most often identified intrinsic factors such as genetics or biology as causes of mental illness. Some support participants believed that unintentional drug use had precipitated the onset of mental illness or had no causal theories. The fact that some support participants could not identify a causal explanation may indicate failure on the part of mental health care systems to engage with consumers’ social support networks and provide education about mental illness and its causes. The implications of etiology beliefs on mental health service utilization are discussed. 相似文献
949.
950.
Michael R. Woodford Jessica Y. Joslin Erich N. Pitcher Kristen A. Renn 《Journal of Ethnic & Cultural Diversity in Social Work》2017,26(1-2):95-111
ABSTRACTThe experiences, including with environmental microaggressions, and well-being of trans* collegians remain an under-researched topic. In this mixed-methods study of a survey sample of 152 trans* collegians, multivariable regression findings suggest that the frequency of experiencing select trans* environmental microaggressions (e.g., not having access to comfortable bathrooms as a trans* person) are associated with increased risk for poorer academic outcomes (e.g., developmental challenges) but are not associated with mental health outcomes. Furthermore, interviews with 18 trans* collegians suggest that students face several systemic microaggressions, including difficulties advancing trans* inclusion. Various reactions, including paths of resistance, were identified. Implications are discussed. 相似文献