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171.
Abstract

In this essay, I suggest that artistic production provides valuable insights into the nature of the Canada-US border during the late-twentieth century when significant changes were occurring to dominant understandings of Canada in relation to North America. Focusing on the medium of video art, I trace the sustained engagement of Canadian contemporary artists to respond to and comment on the move towards continental integration through free trade. I contextualize my discussion in relation to trade developments that opened Canada’s border with the US, such as the 1989 implementation of the Canada-US Free Trade Agreement. This agreement, along with the later North American Free Trade Agreement, led to increasing continental integration at the end of the twentieth century, as well as hope for hemispheric integration with the subsequent negotiations towards the Free Trade Area of the Americas. With attention to works by Lisa Steele and Kim Tomczak, Eva Manly, and Clive Robertson, I foreground cultural contributions to redefining the Canada-US borderlands. Here, I chart the artists’ intention to echo narratives of the border’s porousness and address the power dynamics between the Canadian state and its trade partners. Examining themes of cultural imperialism, colonialism, and national identity, I point to the importance of cultural production in assessing the borderlands and, more broadly, histories of free trade in North America.  相似文献   
172.
Gaze is one of the main means of communication in young infants, and it has been shown to be important for subsequent socio‐emotional and cognitive development. Maternal depression is a well‐known risk factor for disrupting mother–infant interactions, but findings regarding gaze behavior in infants of depressed versus nondepressed mothers have been ambiguous. In this study, we examined gaze duration and activity in a sample of 27 infants of mothers with postpartum depression (PPD) and 49 infants of nondepressed mothers. Maternal depressive symptoms were assessed with the Edinburgh Postnatal Depression Scale, and diagnoses were confirmed in clinical interview. Infant gaze was assessed during 4‐month face‐to‐face interactions using continuous timed‐event coding with high temporal resolution. Although we found no differences in gaze duration, infants of PPD mothers had both significantly less Gaze On and also less Gaze Off events. Findings suggest that PPD is related to reduced gaze activity during mother–infant interaction in 4‐month‐olds. This reduced activity may have long‐term negative consequences for child development.  相似文献   
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Parental influence on friendships between native (= 5,683) and immigrant (= 3,371) adolescents (aged ± 15) was investigated with the CILS4EU data of pupils in German and Dutch school classes (= 446) and parents. The researchers examined whether parents affect friendships across group boundaries by shaping the structural opportunities to establish out‐group friends and their children's out‐group attitudes. The results show that if parents have more out‐group friends and if they consider it less important to maintain in‐group traditions, their children have more out‐group friends. Part of this relationship is mediated by children's out‐group attitudes. Some evidence is found that the opportunity structure mediates the relationship between parental characteristics and adolescent out‐group friendship.  相似文献   
177.
Many oncology studies incorporate a blinded independent central review (BICR) to make an assessment of the integrity of the primary endpoint, progression free survival. Recently, it has been suggested that, in order to assess the potential for bias amongst investigators, a BICR amongst only a sample of patients could be performed; if evidence of bias is detected, according to a predefined threshold, the BICR is then assessed in all patients, otherwise, it is concluded that the sample was sufficient to rule out meaningful levels of bias. In this paper, we present an approach that adapts a method originally created for defining futility bounds in group sequential designs. The hazard ratio ratio, the ratio of the hazard ratio (HR) for the treatment effect estimated from the BICR to the corresponding HR for the investigator assessments, is used as the metric to define bias. The approach is simple to implement and ensures a high probability that a substantial true bias will be detected. In the absence of bias, there is a high probability of accepting the accuracy of local evaluations based on the sample, in which case an expensive BICR of all patients is avoided. The properties of the approach are demonstrated by retrospective application to a completed Phase III trial in colorectal cancer. The same approach could easily be adapted for other disease settings, and for test statistics other than the hazard ratio. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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This study reports on the preliminary development and validation of the Social and Emotional Health Survey (SEHS) with a sample of 4,189 (51 % female) California students in Grades 8, 10, and 12. The SEHS was designed to measure the psychological building blocks of adolescents’ positive mental health and is operationalized in the present study by a theoretical model comprised of 12 measured indicators that form four first-order domains (belief-in-self, belief-in-others, emotional competence, and engaged living) that, in turn, contribute to one underlying, second-order meta-construct called covitality. This study was the first to investigate the validity and utility of the adolescent covitality construct, which is conceptualized as the synergistic effect of positive mental health resulting from the interplay among multiple positive-psychological building blocks. Findings from confirmatory factor analyses, invariance analysis, and latent means testing all supported the theoretical model underlying the SEHS, indicating that the second-order covitality model was the best fit for both males and females. Results from a path-modeling analysis indicated that covitality was a strong predictor of students’ subjective well-being (operationalized as a composite of life satisfaction, positive affect, and negative affect), and findings from additional concurrent validity analyses indicated that adolescents’ covitality level was significantly associated with self-reported academic achievement, perceptions of school safety, substance use, and experiences of depressive symptoms. Implications for theory, practice, and future research are discussed.  相似文献   
180.
Projections of total population have been evaluated extensively, but few studies have investigated the performance of projections by age. Of those that did, most focused on projections for countries or other large areas. In this article, we evaluate projections by age for Florida and its counties, as produced and published between 1996 and 2010 by the Bureau of Economic and Business Research at the University of Florida. We first compare the precision and bias of projections of total population with the precision and bias of projections by age, at both the state and county levels. This is followed by a more detailed examination of county-level projection errors for individual age groups, first in the aggregate and then disaggregated by sex and population size. The second part of the analysis focuses on a number of adjustments that were implemented in projections published in 2006 and 2009. Intended to improve accuracy, these adjustments involved updates to the base population, fertility rates, and survival rates. We compare the accuracy of projections incorporating these adjustments with the accuracy of projections excluding them. We believe this study offers a unique opportunity to examine a variety of characteristics regarding the forecast accuracy of small-area population projections by age.  相似文献   
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