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Using prospective, longitudinal data spanning 10 years (age = 10–20) from a study of 295 economically disadvantaged males, the current investigation evaluated a developmental model that links early family environment and later educational aspirations, extracurricular activities, and educational attainment to substance use in early adulthood. The results indicate that a positive family environment during adolescence (low family conflict, high family warmth, and effective child management) predicted educational involvements during adolescence that promoted educational attainment during early adulthood. Finally, higher levels of educational attainment were associated with less substance use in early adulthood, even after controlling for adolescent substance use. These findings suggest that positive parenting promotes educational achievements that increase resilience to substance use for economically disadvantaged males.  相似文献   
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Intellectual performance is highly heritable and robustly predicts lifelong health and success but the earliest manifestations of genetic effects on this asset are not well understood. This study examined whether early executive function (EF) or verbal performance mediate genetic influences on subsequent intellectual performance, in 561 U.S.-based adoptees (57% male) and their birth and adoptive parents (70% and 92% White, 13% and 4% African American, 7% and 2% Latinx, respectively), administered measures in 2003–2017. Genetic influences on children's academic performance at 7 years were mediated by verbal performance at 4.5 years (β = .22, 95% CI [0.08, 0.35], p = .002) and not via EF, indicating that verbal performance is an early manifestation of genetic propensity for intellectual performance.  相似文献   
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The present study leveraged data from a longitudinal adoption study of 361 families recruited between 2003 and 2010 in the United States. We investigated how psychopathology symptoms in birth parents (BP; Mage = 24.1 years; 50.5–62.9% completed high school) and adoptive parents (AP; Mage = 37.8 years; 80.9% completed college; 94% mother–father couples) influenced children's behavioral inhibition (BI) trajectories. We used latent growth models of observed BI at 18 and 27 months, and 4.5 and 7 years in a sample of adopted children (Female = 42%, White = 57%, Black = 11%, Multi-racial = 21%, Latinx = 9%). BI generally decreased over time, yet there was substantial variability in these trajectories. Neither BP nor AP psychopathology symptoms independently predicted systematic differences in BI trajectories. Instead, we found that AP internalizing symptoms moderated the effects of BP psychopathology on trajectories of BI, indicating a gene by environment interaction.  相似文献   
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An improvement on the transient response of tracking for the sampled-data system based on an improved PD-type iterative learning control (ILC) is proposed in this paper. The developed analog ILC method and the high-gain property tracker design methodology are first combined to significantly reduce learning epochs and overcome the initial condition shift problem and discontinuous reference input in the traditional ILC. Besides, the proposed ILC improves the transient response and decreases the rate of weighting matrices QQ to RR under the traditional linear quadratic tracker design. First, the off-line observer/Kalman filter identification (OKID) is used to determine the appropriate (low-) order system parameters and state estimator for the physical system with unknown system equation, so that the model-based PD-type ILC can be implemented for practical applications. Then, to improve the transient response and decrease the control effort, the proportional difference type (PD-type) ILC algorithm is combined with the high-gain property linear quadratic tracker (LQT) design to construct the high performance tracker for the model-based sampled-data systems. Furthermore, the discrete-time version high performance tracker design for the unknown stochastic sampled-data system via the iterative learning control method is proposed in this paper based on the Euler method and the digital redesign approach. Finally, some examples are given for illustrating the effectiveness of the proposed method.  相似文献   
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在全民健身和军民融合两大国家战略交汇点上,同根同源而生的体育与军事理应深度融合、协同发展。本研究通过文献资料费、专家访谈法和实践调查法,梳理在体育管理获得、体育竞赛表演活动和体育教育培训等体育产业的军民融合发展情况,梳理在武器装备科研生产、军队人才培养和军队社会化保障等军民融合重点领域的体育产业发展情况,梳理国外体育产业与军民融合发展情况,总结提出我国当前体育产业的军民融合发展水平整体不高,但是存在很大上升空间,发展前景广阔、潜力巨大,我国体育产业军民融合发展急需顶层设计、中层协调、基层落实。  相似文献   
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