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971.
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974.
In this paper in general the dynamic effects are considered and described, caused by different stand-ing waves in discrete and distributed systems with impacts and other strongly positional non-linear fac-tors, introduction of which in the models of me-chanical objects is dictated by the necessity to con-sider processes, accompanied with impacts of me-chanical subsystems of different nature.  相似文献   
975.
用不同于已有文献的方法研究了一类高阶中立型微分方程,本文不需要条件f∞t0Q(s)ds=∞,获得了这类方程振动性的几个新的结果.  相似文献   
976.
Presidential election campaigns provide opportunities for parents to socialize their children to become politically engaged citizens. However, news coverage of the 2016 U.S. presidential campaign contained inappropriate content, leading parents to possibly restrict or denigrate rather than encourage child campaign news consumption. This study built on literatures in political socialization and parental mediation to explore mediation of campaign news coverage. Data from a representative sample of American parents during the Autumn of 2016 revealed that co-viewing, active mediation, and restrictive mediation were relatively common. The predictors of mediation included political variables, parenting orientations, and child factors, with the latter two often interacting with one another. The results have implications for how we conceptualize both political socialization and parental mediation.  相似文献   
977.
978.
#MeToo has breathed new life into the women’s movement and especially into understanding and rectifying sexual harassment, abuse and assault. It has galvanized activists around the globe. And it has placed thousands of stories of the harassed in full view of the public. Sexual harassment, abuse and assault may occur within the organizational context or beyond; but sexual harassment, in particular has been legally labeled an organizational phenomenon. With this in mind, Robin Clair frames the early part of this article around the most recent organizational communication theories (see the appendix for an overview of these theories). Following the essay is a forum, in which invited scholars address questions related to the #MeToo movement.  相似文献   
979.
In the United States today, urban schools serve the majority of high-poverty and high minority populations including large numbers of Hispanic students. While many Hispanic students perform below grade level in middle school science, the science teaching community as a whole is lacking elements of diversity as teachers struggle to meet the needs of all learners. Researchers have recognized that science teacher effectiveness, one consequence of self-efficacy among teachers, is associated with future science achievement and science-related careers of their students. This qualitative study explores how three science teachers’ effectiveness in the classroom impacts students’ science self-efficacy beliefs at one urban middle school. Hispanic students were the focus of this investigation due to demographics and history of underperformance within this district. Teachers’ perspectives, as well as outside observer evaluations of instructional strategies and classroom climates were triangulated to explore dynamics that influence students’ interests and motivation to learn science using a framework to link teachers’ sense of efficacy (focusing on student outcomes). Findings suggest the impact teacher effectiveness can have on student outcomes, including strengthened student science self-efficacy and increased science achievement. Building awareness and support in teachers’ sense of efficacy, as well as developing respectful and supportive relationships between educator/facilitator and pupil during the transition to middle school may construct permanence and accomplishment for all in science.  相似文献   
980.
Science education in the United States will increasingly be driven by testing and accountability requirements, such as those mandated by the No Child Left Behind Act, which rely heavily on learning outcomes, or "standards," that are currently developed on a state-by-state basis. Those standards, in turn, drive curriculum and instruction. Given the importance of standards to teaching and learning, we investigated the quality of life sciences/biology standards with respect to genetics for all 50 states and the District of Columbia, using core concepts developed by the American Society of Human Genetics as normative benchmarks. Our results indicate that the states' genetics standards, in general, are poor, with more than 85% of the states receiving overall scores of Inadequate. In particular, the standards in virtually every state have failed to keep pace with changes in the discipline as it has become genomic in scope, omitting concepts related to genetic complexity, the importance of environment to phenotypic variation, differential gene expression, and the differences between inherited and somatic genetic disease. Clearer, more comprehensive genetics standards are likely to benefit genetics instruction and learning, help prepare future genetics researchers, and contribute to the genetic literacy of the U.S. citizenry.  相似文献   
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