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991.
ABSTRACT

This quarter's column reports on sessions from NASIG 2017: Racing to the Crossroads, held in Indianapolis, IN, June 8 to 11, and ALA Annual 2017: Transforming Our Libraries, Ourselves, which took place in Chicago, IL, June 22–27.  相似文献   
992.
993.
Stepped wedge trials are increasingly adopted because practical constraints necessitate staggered roll-out. While a complete design requires clusters to collect data in all periods, resource and patient-centered considerations may call for an incomplete stepped wedge design to minimize data collection burden. To study incomplete designs, we expand the metric of information content to discrete outcomes. We operate under a marginal model with general link and variance functions, and derive information content expressions when data elements (cells, sequences, periods) are omitted. We show that the centrosymmetric patterns of information content can hold for discrete outcomes with the variance-stabilizing link function. We perform numerical studies under the canonical link function, and find that while the patterns of information content for cells are approximately centrosymmetric for all examined underlying secular trends, the patterns of information content for sequences or periods are more sensitive to the secular trend, and may be far from centrosymmetric.  相似文献   
994.
This study aimed to examine changes in depression and anxiety symptoms from before to during the first 6 months of the COVID-19 pandemic in a sample of 1,339 adolescents (9–18 years old, 59% female) from three countries. We also examined if age, race/ethnicity, disease burden, or strictness of government restrictions moderated change in symptoms. Data from 12 longitudinal studies (10 U.S., 1 Netherlands, 1 Peru) were combined. Linear mixed effect models showed that depression, but not anxiety, symptoms increased significantly (median increase = 28%). The most negative mental health impacts were reported by multiracial adolescents and those under ‘lockdown’ restrictions. Policy makers need to consider these impacts by investing in ways to support adolescents’ mental health during the pandemic.  相似文献   
995.
We investigated how exogenous variation in exposure to the COVID-19 pandemic during the first year of life is related to infant development, maternal mental health, and perceived stress. Ninety-three socioeconomically diverse pregnant women were recruited before the pandemic to participate in a longitudinal study. Infants ranged in age at the beginning of lockdown (0–9.5 months old), thus experiencing different durations of pandemic exposure across the first year of life. The duration of pandemic exposure was not associated with family demographic characteristics, suggesting it captured exogenous variability. We tested associations between this exogenous variation in pandemic exposure and child and family outcomes. We also examined whether mother-reported disruptive life events were correlated with child and family outcomes. We found no association between duration of pandemic exposure in the first year of life and infant socioemotional problems, infant language development, or maternal mental health and perceived stress symptoms, at 12 or 24 months. However, we found that self-reported exposure to pandemic-related disruptive life events predicted greater maternal depression, anxiety, and perceived stress at 12 months, and greater depression and anxiety at 24 months. Socioeconomic status did not moderate these associations. These findings suggest cautious optimism for infants raised during this period.  相似文献   
996.
Despite strong indications of elevated risk of suicidal behavior in lesbian, gay, bisexual, and transgender people, limited attention has been given to research, interventions or suicide prevention programs targeting these populations. This article is a culmination of a three-year effort by an expert panel to address the need for better understanding of suicidal behavior and suicide risk in sexual minority populations, and stimulate the development of needed prevention strategies, interventions and policy changes. This article summarizes existing research findings, and makes recommendations for addressing knowledge gaps and applying current knowledge to relevant areas of suicide prevention practice.  相似文献   
997.
998.
The study of leadership emergence has increased substantially over the past few decades. However, due to a lack of integrative theory, we believe limited advancement has been made regarding the full process of leadership emergence. To address this concern, first, we conceptualize the leadership emergence process from a complexity perspective and define emergence as a dynamic, interactive process grounded in three principles of emergent phenomena. Second, we review how previous research has modeled leadership emergence by focusing on the content areas of the lower-level elements, the mechanisms that facilitate their emergence, and the dynamism of the process once it has emerged. Third, based on the findings from the review, we introduce a process-oriented framework of leadership emergence. Fourth, we offer propositions to guide developing and testing emergent leadership processes, and we conclude with recommendations for future leadership process research. Our hope is that by realigning the study of leadership emergence with complexity and multilevel theory, we can reorient this area to focusing more on the process mechanisms within emergence, connecting back to research progress made over 60?years ago.  相似文献   
999.
The paper examines in detail one particular measure of variable importance for linear regression that was theoretically justified by Pratt (1987), but which has since been criticized by Bring (1996) for producing “counterintuitive” results in certain situations, and by other authors for failing to guarantee that importance be non-negative. In the article, the “counterintuitive” result is explored and shown to be a defensible characteristic of an importance measure. It is also shown that negative importance of large magnitude can only occur in the presence of multicollinearity of the explanatory variables, and methods for applying Pratt's measure in such cases are described. The objective of the article is to explain and to clarify the characteristics of Pratt's measure, and thus to assist practitioners who have to choose from among the many methods available for assessing variable importance in linear regression.  相似文献   
1000.
Extant research suggests that parents are more depressed than childless adults, yet the role of pregnancy intentions is largely absent from the discussion. Using 2 waves of data from the National Survey of Families and Households (n = 825 women, n = 889 men), the author found that pregnancy intentions are an important consideration for parents' well‐being. The results suggest that unintended births are associated with increased depressive symptoms among fathers and decreased happiness among mothers. This association persisted even after accounting for union status and measures of depressive symptoms and happiness prior to the birth. The author also investigated the social, psychological, and economic mechanisms that explain this relationship. Self‐efficacy and financial strain partially explain the link between unintended births and poorer well‐being.  相似文献   
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