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991.
Sarah G. Curci Linda J. Luecken Marisol Perez Rebecca M.B. White 《Child development》2021,92(5):1785-1800
Socioeconomically disadvantaged neighborhoods increase the risk for poor mental health among residents, yet protective factors may operate alongside risk. This study evaluated the influence of the prenatal neighborhood ethnocultural context on child behavior problems and maternal depressive symptoms. Prenatal maternal role expectations, prenatal culture-specific stress, and postpartum depression (PPD) symptoms were evaluated as mediators. Participants included 322 low-income, Mexican American mother-child dyads. Women (Mage = 27.8) reported on proposed mediators, maternal depressive symptoms, and child behavior problems at 4.5 years. Neighborhood Latinx concentration was obtained from census data. Higher Latinx concentration predicted fewer maternal depressive symptoms and child behavior problems, mediated through role expectations and PPD symptoms. Results suggest prenatal neighborhood context to impact later maternal and child mental health. 相似文献
992.
A number of psychometricians have suggested that parallel analysis (PA) tends to yield more accurate results in determining the number of factors in comparison with other statistical methods. Nevertheless, all too often PA can suggest an incorrect number of factors, particularly in statistically unfavorable conditions (e.g., small sample sizes and low factor loadings). Because of this, researchers have recommended using multiple methods to make judgments about the number of factors to extract. Implicit in this recommendation is that, when the number of factors is chosen based on PA, uncertainty nevertheless exists. We propose a Bayesian parallel analysis (B-PA) method to incorporate the uncertainty with decisions about the number of factors. B-PA yields a probability distribution for the various possible numbers of factors. We implement and compare B-PA with a frequentist approach, revised parallel analysis (R-PA), in the contexts of real and simulated data. Results show that B-PA provides relevant information regarding the uncertainty in determining the number of factors, particularly under conditions with small sample sizes, low factor loadings, and less distinguishable factors. Even if the indicated number of factors with the highest probability is incorrect, B-PA can show a sizable probability of retaining the correct number of factors. Interestingly, when the mode of the distribution of the probabilities associated with different numbers of factors was treated as the number of factors to retain, B-PA was somewhat more accurate than R-PA in a majority of the conditions. 相似文献
993.
Laerke Sass Elín Bjarnadóttir Jakob Stokholm Bo Chawes Rebecca K. Vinding Anna-Rosa C. Mora-Jensen Jonathan Thorsen Sarah Noergaard Bjørn H. Ebdrup Jens R.M. Jepsen Birgitte Fagerlund Klaus Bønnelykke Lotte Lauritzen Hans Bisgaard 《Child development》2021,92(4):1624-1635
A double-blind randomized controlled trial of n-3 long-chain polyunsaturated fatty acid (n-3 LCPUFA) supplementation or matching placebo during third trimester of pregnancy was conducted within the COPSAC2010 mother-child cohort consisting of 736 women and their children. The objective was to determine if maternal n-3 LCPUFA pregnancy supplementation affects offspring neurodevelopment until 6 years. Neurodevelopment was evaluated in 654 children assessing age of motor milestone achievement, language development, cognitive development, general neurodevelopment, and emotional and behavioral problems. Maternal n-3 LCPUFA supplementation during pregnancy improved early language development and reduced the impact of emotional and behavioral problems. The n-3 LCPUFA supplementation was in boys associated with the earlier achievement of gross motor milestones, improved cognitive development, and a reduced impact of emotional and behavioral problems. 相似文献
994.
Phillippo Kate Griffin Briellen Del Dotto B. Jacob Lennix Crystal Tran Ha 《The Urban Review》2021,53(4):591-616
The Urban Review - School choice policy is ubiquitous in urban school districts. Evidence suggests that it has not fully delivered on its proponents’ promises of equitable educational... 相似文献
995.
Children's Literature in Education - Oliver Jeffers’ best-selling picturebook How to Catch a Star (2004) has been the subject of several recent theatre adaptations for children. This... 相似文献
996.
Research in Science Education - This paper addresses two methodological issues related to the assessment of teachers’ views of science. The first concerns the distinction between the... 相似文献
997.
Sam Parsons Alice Sullivan Vanessa Moulton Emla Fitzsimons George B. Ploubidis 《British Educational Research Journal》2021,47(5):1361-1387
Behaviour problems in early childhood have a lasting impact on cognitive development and education attainment in later adolescence and into adulthood. Here we address the relationship conduct and hyperactivity problems at school entrance, and vocabulary acquisition in adolescence. We compare performance in identical assessments across two generations of British children born 30 years apart in 1970 (n = 15,676) and 2000/2 (n = 16,628) and find that both conduct and hyperactivity problems have a negative association with later vocabulary in both generations. We take advantage of rich longitudinal birth cohort data and establish that these relationships hold once family socioeconomic status and a child’s personal characteristics and earlier vocabulary acquisition are taken into account. We also find that teenagers today achieved substantively lower scores in the vocabulary assessment compared to their counterparts born 30 years earlier, and that this holds across all categories within each of the family and individual characteristics considered in this article. As vocabulary and language skills are key prerequisites for wider learning, we discuss implications the findings have for education policies. 相似文献
998.
Dynamic problems of axially moving materials as exemplified by strings in textile industry and band saws, belts and chains in mechanical machinery have recently received some attention (1–15). In the present study, the parametric resonance of an axially accelerated beam is investigated. The beam which has encastré ends is subjected to a periodic root force as shown in Fig. 1. The object of the investigation is to identify regions of instability of this system for various combinations of the excitation frequency and amplitude of the axial oscillations. 相似文献
999.
Nancy B. Kurland 《The Information Society》1996,12(4):387-406
Information technology in the form of the Internet and its commercial offspring (referred to in this article collectively as the Net) has received much attention as a vehicle to increase political participation. In this article, we explore the potential of the Net, a vast, loosely coupled system of electronic forums, for facilitating and hindering democratic participation. In so doing, we identify five assumptions that undergird the claim that the Net will enhance democratic participation and suggest that increased democratic participation rests on three fundamental characteristics: access, voice, and dialogue. In order for this network of electronic forums to facilitate democratic participation, educational, economic, and cultural barriers to access, voice, and dialogue must be overcome. The final part of this article raises additional challenges to realizing democracy via the Net. 相似文献
1000.
Syed Shamil B.Sc. Ph.D. C.Chem. M.R.S.C. M.I.F.S.T. Gordon G. Birch B.Sc. Ph.D. D.Sc. F.R.C.S. F.I.F.S.T. 《Endeavour》1990,14(4)
Of all the senses, that of taste is perhaps the hardest to define and quantify and elucidation of the underlying mechanisms is unrespondingly difficult. This article describes a conceptual model — at the molecular level — for the four basic taste modalities, using apparent specific volume as a fundamental parameter. It also considers possible practical applications. 相似文献