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141.
The authors used a large sample of children (N ≈ 7,400) participating in the Early Childhood Longitudinal Study--Kindergarten Cohort (ECLS-K) to estimate kindergarten children's academic achievement growth trajectories in reading and mathematics. The authors were particularly interested in whether the growth trajectories of children with learning disabilities (LD) or speech language impairments (SLI)--as well as those of other groups of children--were consistent with a cumulative or compensatory developmental cycle. Both LD and SLI children displayed significantly lower levels of kindergarten reading achievement than nondisabled children. However, and over the subsequent 5 years of elementary school, only children with SLI lagged increasingly behind nondisabled peers in their reading skills growth. The authors observed a different pattern for mathematics achievement. Children with LD, but not SLI, lagged increasingly behind nondisabled children in their mathematics skills growth. The authors also observed some consistency in "poor-get-poorer" effects across reading and mathematic achievement for additional population subgroups. Those kindergarten children who were from lower socioeconomic status families, who were African American, and who more frequently displayed learning-related behavior problems initially had lower levels of reading and mathematics achievement and also lagged increasingly behind in their acquisition of these skills over time. Some groups of children, including those with SLI, experience a cumulative rather than a compensatory cycle of achievement growth. 相似文献
142.
In this paper, we utilize transmission-line matrix simulations to study the electromagnetic properties of hyperbolic metamaterial grids, which are synthesized by arranging unloaded transmission lines over electrical ground planes, such that the unit cells are rectangular in shape. The hyperbolic grids support Bragg and Hyperbolic resonant modes that have rectangular and hyperbolic dispersion surfaces, respectively. We demonstrate the formation of these resonant modes in the hyperbolic grids and their refraction, and spatial scanning properties via circuit simulations. The simulation results are compared with experimental results of a two-layer anisotropic hyperbolic metamaterial. 相似文献
143.
Saraslanidis P Petridou A Bogdanis GC Galanis N Tsalis G Kellis S Mougios V 《Journal of sports sciences》2011,29(11):1167-1174
Repeated-sprint training often involves short sprints separated by inadequate recovery intervals. The effects of interval duration on metabolic and performance parameters are unclear. We compared the effects of two training programmes, differing in rest interval duration, on muscle (vastus lateralis) metabolism and sprint performance. Sixteen men trained three times a week for 8 weeks, each training session comprising 2-3 sets of two 80-m sprints. Sprints were separated by 10 s (n = 8) or 1 min (n = 8). Both training programmes improved performance in the 100-, 200-, and 300-m sprints, but the improvement was greater in the 10-s group during the final 100 m of the 200- and 300-m runs. Independent of interval duration, training mitigated the drop of muscle ATP after two 80-m sprints. The drop in phosphocreatine and the increases in glucose-6-phosphate and fructose-6-phosphate after two 80-m sprints were greater in the 10-s group. In conclusion, training with a limited number of repeated short sprints (≤10 s) may be more effective in improving speed maintenance in 200- and 300-m runs when performed with a 1:1 rather than a 1:6 exercise-to-rest ratio. This may be due to a greater activation of glycolysis caused, in part, by the limited resynthesis of phosphocreatine during the very short rest interval. 相似文献
144.
Harrell Pamela Esprvalo Kirby Benjamin Subramaniam Kartheyan Long Chris 《International Journal of Science and Mathematics Education》2022,20(2):299-320
International Journal of Science and Mathematics Education - This research study investigated conceptions about buoyancy held by 55 elementary preservice teachers enrolled in a science methods... 相似文献
145.
George Vukotich 《Performance Improvement》2014,53(1):30-35
This article looks at 360° feedback, as well as mistakes and misuses that are often made in its implementation and use. Too often individuals look for tools to give them facts to support predetermined opinions rather than gathering facts to support individuals in their growth and development process. By identifying these issues and addressing them up front, larger issues that can negatively affect the overall culture of an organization can be avoided. 相似文献
146.
Mindy Steadman Benjamin Crookston Randy Page 《American journal of sexuality education》2014,9(3):347-369
Sexuality education programs can be broadly categorized as either risk-avoidance or risk-reduction approaches. Health educators in Utah public schools must teach a state mandated risk-avoidance curriculum which prohibits the advocacy or encouragement of contraception. Multiple national surveys indicate that parents prefer a risk-reduction approach to sexuality education that promotes abstinence and the use of condoms or contraception for prevention of unwanted pregnancy and sexually transmitted infection. To date, no survey of Utah parents has been conducted.This study utilized an Internet survey to gather data from 344 Utah parents to analyze their preferences regarding school-based sexuality education, sexuality topics, and support for objectives from the National Sexuality Education Standards. The vast majority of Utah parents surveyed support a risk-reduction approach to sexuality education, a wide variety of sexuality topics, and the majority of National Sexuality Education Standards. Statistically significant differences were identified by parents’ education, income, attendance at religious services, and political affiliation. Results support that Utah laws and education policies should be reexamined to provide for instruction that aligns with professional recommendations, best-practice recommendations based on peer-reviewed research, parental attitudes, and the needs of Utah teens. 相似文献
147.
Benjamin D. Plummer Brian M. Galla Amy S. Finn Sarah D. Patrick David Meketon Julia Leonard Calvin Goetz Elizabeth Fernandez‐Vina Sara Bartolino Rachel E. White Angela L. Duckworth 《Mind, Brain, and Education》2014,8(1):15-20
Schools are an important context for both basic and applied scientific research. Unlike the laboratory, however, the physical and social conditions of schools are not under the exclusive control of scientists. In this article, we liken collecting data in schools to putting on a theatrical production. We begin by describing the large cast of characters whose collaborative efforts make school‐based research possible. Next, we address the critics, including the university Institutional Review Board (IRB) and school administrators, whose feedback often improves the final study design. We then turn our attention to set building, stage directions, and rehearsals—key steps in the iterative process of refining study procedures. We end with a discussion of the day of data collection itself and activities that take place after the curtain drops. Throughout, we make recommendations based on our recent experience collecting data at several high schools. 相似文献
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