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71.
研究具有比例时滞和正负系数的二阶非线性中立型微分方程[x(t)±r(t)f(x(αt))]″+p(t)g(x(tβ))-q(t)h(x(tγ))=0,建立方程解的振动以及非振动解渐近稳定的充分条件。  相似文献   
72.
In a literature where different research approaches generate inconsistent effects, we examine negative TV advertising effects on public support ratings of presidential candidates over time. Weekly national advertising and poll data from 2011 and 2012 were analyzed via (a) pooled time series analysis with growth curve modeling and (b) individual time serial dependency analysis with autoregressive integrated moving average. Study results support a social influence model derived from attribution theory, wherein negative TV ads did, in fact, influence poll results or public support ratings. In particular, spending on negative advertising increased the support for the sponsor of such ads. We also uncover a reciprocal effect of negative advertising between the competing candidates over time, such that spending on negative advertising attacking Mitt Romney predicted spending on advertising attacking Barack Obama in about 4 weeks at Lag 3 and Lag 4. Findings establishing the efficacy of negative advertising are discussed in the context of game theory.  相似文献   
73.
Community colleges are typically relied upon to address many challenges in United States higher education and, more recently, are under public pressure to increase student completion rates. This article presents a case study of colleagues at three Minnesota community colleges as they work together to address student and program needs. While traditionally community colleges tend to focus primarily on gaining transfer partnerships with universities, we suggest that collaborations across community college programs may be key to long-term success. If done well, such sister program collaborations can support a trajectory of programmatic strength that not only bolsters the curriculum, enrollment, and program visibility, but also ultimately supports students’ ability to complete and successfully transfer. The result, then, is that university partners are attracted and sustained by a vibrant network of colleagues and a pipeline of student support.  相似文献   
74.
SYNOPSIS

Objective : Vagal suppression is a parasympathetic physiological indicator of emotion regulation and social engagement behaviors, often measured via heart rate variability. Experiential avoidance reflects psychological inflexibility or poor emotion regulation. We tested the interaction effects of parental vagal suppression and experiential avoidance on observed parenting behaviors among combat deployed fathers. Design . We analyzed data from 92 male National Guard/Reserve members who had returned from a deployment to Iraq and/or Afghanistan since 2001. They were mostly European American, in their 30s, middle-class, and married. All fathers participated in home-based assessments with their spouses (if married) and a target child aged 4–13 years. Fathers’ vagal suppression was measured as the decrease in cardiac vagal tone (i.e., high frequency heart rate variability) from a neutral reading task to a father-child conflict resolution task. Experiential avoidance was self-reported. Parenting behaviors were observed during family interaction tasks and coded into positive engagement and withdrawal avoidance using a macro-level coding system. Results . Multiple regression analysis showed no main effects of vagal suppression on observed parenting, but interaction effects of experiential avoidance by vagal suppression on observed parenting. Specifically, among fathers with higher vagal suppression, we found no relations between experiential avoidance and observed parenting; among fathers with lower vagal suppression, we found an inverse association between experiential avoidance and positive engagement as well as a positive association between experiential avoidance and withdrawal avoidance. Conclusions . The effect of psychological inflexibility on military fathers’ parenting behaviors was moderated by vagal suppression. The findings have implications for the linkage between emotion regulation and parenting in military fathers.  相似文献   
75.
The purposes of this study were to determine the extent of family-centered practices, professionals' and families' values about the practices, and the extent to which selected characteristics of participants explained variance in the practices. Professionals (N = 198) and families (N = 118) completed two questionnaires. Professionals tended to report more family-centered typical practice than did families, but ideal practices generally did not vary between groups. Agency type and the Setting x Experience interaction predicted professionals' ideal-practice scores and their self-ratings of the frequency of implementing family-centered practices: Home-based services were most predictive of frequent reports of these practices. The frequency with which families reported receiving these practices was predicted by the amount of time the family had been in early intervention: The longer, the more frequently families experienced the practices.  相似文献   
76.
正三届数独世界冠军托马斯·辛德(Thomas Snyder)为《大学生》读者们专门设计数独题。辛德曾三次获得数独世界冠军,五次夺得美国数独冠军,他的专业是化学,本科毕业于加州理工学院,在哈佛大学取得博士学位,现是斯坦福大学生物工程学助理研究员。辛德爱好数独,用艺术手法设计数独题。请看题:游戏规则:在9X9的方阵中,每一行与每一列都有1到9的数字,每个3X3的小方阵也有1到9的数字,并且一个数字在每行、每列及小方阵中只能出现一次,既不能重复也不能缺少。  相似文献   
77.
Summer undergraduate research programs in science and engineering facilitate research progress for faculty and provide a close-ended research experience for students, which can prepare them for careers in industry, medicine, and academia. However, ensuring these outcomes is a challenge when the students arrive ill-prepared for substantive research or if projects are ill-defined or impractical for a typical 10-wk summer. We describe how the new Bioengineering and Bioinformatics Summer Institutes (BBSI), developed in response to a call for proposals by the National Institutes of Health (NIH) and the National Science Foundation (NSF), provide an impetus for the enhancement of traditional undergraduate research experiences with intense didactic training in particular skills and technologies. Such didactic components provide highly focused and qualified students for summer research with the goal of ensuring increased student satisfaction with research and mentor satisfaction with student productivity. As an example, we focus on our experiences with the Penn State Biomaterials and Bionanotechnology Summer Institute (PSU-BBSI), which trains undergraduates in core technologies in surface characterization, computational modeling, cell biology, and fabrication to prepare them for student-centered research projects in the role of materials in guiding cell biology.  相似文献   
78.
This article proposes a distinct role for solitude in education, specifically as a means of promoting self-realisation. Solitude is understood as a willed disengagement, as described by Koch, and its relationship to loneliness and to silence is explained. Notwithstanding a degree of disengagement, solitude can be and often is experienced as dialogic, with dialogue not only being internal (dialogue with the self) but also with others, near or distant. Self-realisation is described positively in terms of Macmurray's ‘becoming more real’ and the deep ecology of Naess, and is distanced from psychological and psychotherapeutic approaches to self-actualisation and self-esteem, not least because self-realisation may involve a significant degree of suffering. Drawing on philosophical and literary sources from both Anglophone and Polish traditions, the significance of this research for schooling is not simply organisational (i.e. organising opportunities for those in school to have positive experiences of solitude) but moral and political.  相似文献   
79.
80.
The opportunities for outreach activities for professionals and academics in food science are extensive, as too are the range of participants’ experience levels and platforms for delivery. Here, we present a set of activities that are readily adaptable for a range of students (ages 10 to 18) in multiple platforms (demonstration table and hands‐on workshop). Our activity, collectively called “The Science of a Sundae,” has three units, one for each of the three parts of a sundae: the caramel sauce, the cherry, and the ice cream. In each unit we use these familiar food items to illustrate how colligative properties (or, simply, “solutions” for younger students) impact the chemical, microbiological, and sensorial properties of food. We have used these activities to present to over 1000 students and their parents/chaperones. Grade levels of student participants have ranged from 5th grade through high school, and these activities have been presented in the form of a demonstration table at science events as well as a set of three 45‐minute workshops in a classroom setting. Educational impact of these activities was evaluated with 7th grade students (n = 77) who participated in the 3‐phase workshop. On average, students who took the posttest (after participation in the workshop) scored 36% higher than students who took the pretest (prior to participation in the workshop). These results and instructor observations suggest the merit of this lesson and its adaptability among ages and platforms.  相似文献   
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