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451.
The goal of the Center for Research on the Education of Students Placed At Risk (CRESPAR) Early Learning program is to ensure that young children reach the 1st grade with the necessary skills and competencies to be effective learners. This goal has been accomplished by 2 integrated areas of research. One area of research focuses on the development of effective practices that promote the development of language and literacy skills in young children. A 2nd area of research examines the systemic issues regarding school policies and teachers' beliefs and expectations that affect classroom practices. Over the past 5 years, the CRESPAR Early Learning Program has been conducting research in these areas, which has added to our understanding of how children learn and what teachers think that they can learn.  相似文献   
452.
Spatial thinking predicts Science, Technology, Engineering, and Mathematics achievement, yet is often absent from educational policy. We provide benchmarks of teachers' usage and perceptions of spatial activities in practice in the reception classroom (first year of primary school). In this questionnaire study of educational professionals working in the reception classroom in England (N = 104), we found that spatial and numeracy activities were perceived as significantly less important, and were reportedly completed significantly less often, than literacy or life skills. Despite the lower perceived importance of spatial skills in curriculum guidance in England, rates of reported spatial activity use were encouragingly high and were broadly comparable to those of numeracy. Teachers had moderate anxiety levels for both spatial and mathematics domains. The findings highlight a need to elevate teachers' understanding of the importance of developing children's early spatial and numeracy skills, which may begin with efforts to reduce spatial and mathematics anxiety.  相似文献   
453.
Disadvantaged neighborhoods confer risk for behavior problems in school‐aged children but their impact in toddlerhood is unknown. Relations between toddlers’ disruptive behavior and neighborhood disadvantage, family disadvantage, violence or conflict exposure, parent depressive symptoms, and parenting behavior were examined using multilevel, multigroup (girl–boy) models. Participants were 1,204 families (mean child age = 24.7 months). Unique associations between disruptive behavior and all risk factors were observed, but the effect of neighborhood disadvantage was negligible when all of the more proximal factors were accounted for. The results suggest both that children in disadvantaged neighborhoods are at greater risk of behavior problems than children in nondisadvantaged neighborhoods and that optimal prevention/intervention work with these children will attend to proximal risk factors.  相似文献   
454.
We investigate adolescent risk factors, measured at both early and late adolescence, for involvement in child maltreatment during adulthood. Comprehensive assessments of risk factors for maltreatment that use representative samples with longitudinal data are scarce and can inform multilevel prevention. We use data from the Rochester Youth Development Study, a longitudinal study begun in 1988 with a sample of 1,000 seventh and eighth graders. Participants have been interviewed 14 times and, at the last assessment (age 31), 80% were retained. Risk factors represent 10 developmental domains: area characteristics, family background/structure, parent stressors, exposure to family violence, parent–child relationships, education, peer relationships, adolescent stressors, antisocial behaviors, and precocious transitions to adulthood. Maltreatment is measured by substantiated reports from Child Protective Services records. Many individual risk factors (20 at early adolescence and 14 at later adolescence) are significantly, albeit moderately, predictive of maltreatment. Several developmental domains stand out, including family background/structure, education, antisocial behaviors, and precocious transitions. In addition, there is a pronounced impact of cumulative risk on the likelihood of maltreatment. For example, only 3% of the youth with no risk domains in their background at early adolescence were involved in later maltreatment, but for those with risk in 9 developmental domains the rate was 45%. Prevention programs targeting youth at high risk for engaging in maltreatment should begin during early adolescence when risk factors are already at play. These programs need to be comprehensive, capable of addressing the multiple and interwoven nature of risk that is associated with maltreatment.  相似文献   
455.
To what extent and why do social origins matter for access to higher education, including access to elite universities? What is the role of private and selective schooling? This paper uses the 1970 British Cohort Study (BCS70) to analyse the trajectories of a generation currently in early middle age. We find that the influence of social origins, especially parental education, remains when both a wide range of cognitive measures and school attainment are controlled. Attending a private school is powerfully predictive of gaining a university degree, and especially a degree from an elite institution, while grammar schooling does not appear to confer any advantage.  相似文献   
456.
The purpose of this study was to examine determinants of Black male students’ engagement with faculty in the community college. Data from this study were derived from the 2011 three-year cohort of the Community College Survey of Student Engagement (CCSSE). Using data from 11,384 Black male respondents within 260 community colleges, this study investigated faculty–student engagement using hierarchical, multilevel modeling. Among other findings, this study illustrated the importance of reading remediation, participation in learning communities, study skills courses, and college orientation in positively contributing to faculty–student interactions. Implications for college practice are discussed.  相似文献   
457.
This study investigated the extent to which early education classrooms across Indiana implemented evidence-based practices and how well the classrooms of different types of early education programs in our state compared with one another. Evidence-based effective curricula increase children’s learning compared to those that are not effective. This article addresses the question: “Are the curricula used by the teachers effective?” The 81 participating classrooms included 28 in licensed child care centers, 27 in Head Start, and 26 in public school prekindergarten. Of the 81 classrooms, 80 teachers responded to the question: “What curriculum or curricula do you use in your classroom?” We used a three-step process to determine whether each response named a curriculum based on the Head Start definition; whether studies of the curriculum met the What Works Clearinghouse (WWC) guidelines for being evidence-based; and if the WWC reviews identified the curriculum as effective in increasing children’s learning. Findings revealed that only 2 of 80 responding teachers used a curriculum determined by WWC to be effective. Other teachers used curricula that did not meet the Head Start definition, used curricula that did not meet the WWC standards for evidence, or used curricula with evidence but that were ineffective. These findings suggest that administrators and teachers should opt for a curriculum determined to be effective and to choose whether the curriculum will be math- or literacy-based since no comprehensive curriculum has been determined to be effective. A challenge for implementation is that the WWC has shown only five curricula to be effective.  相似文献   
458.
Nanofluidics has a unique property that ionic conductance across a nanometer-sized confined space is strongly affected by the space surface charge density, which can be utilized to construct electrical read-out biosensor. Based on this principle, this work demonstrated a novel protein sensor along with a sandwich signal enhancement approach. Nanoparticles with designed aptamer onside are assembled in a suspended micropore to form a 3-dimensional network of nanometer-sized interstices, named as nanofluidic crystal hereafter, as the basic sensing unit. Proteins captured by aptamers will change the surface charge density of nanoparticles and thereby can be detected by monitoring the ionic conductance across this nanofluidic crystal. Another aptamer can further enlarge the variations of the surface charge density by forming a sandwich structure (capturing aptamer/protein/signal enhancement aptamer) and the read-out conductance as well. The preliminary experimental results indicated that human α-thrombin was successfully detected by the corresponding aptamer modified nanofluidic crystal with the limit of detection of 5 nM (0.18 μg/ml) and the read-out signal was enhanced up to 3 folds by using another thrombin aptamer. Being easy to graft probe, facile and low-cost to prepare the nano-device, and having an electrical read-out, the present nanofluidic crystal scheme is a promising and universal strategy for protein sensing.  相似文献   
459.
Abstract

Few studies have focused on the effect of posture during sprint start. The aim of this study was to measure the effect of the modification of horizontal distance between the blocks during sprint start on three dimensional (3D) joint angular velocity. Nine trained sprinters started using three different starting positions (bunched, medium and elongated). They were equipped with 63 passive reflective markers, and an opto-electronic Motion Analysis® system was used to collect the 3D marker trajectories. During the pushing phase on the blocks, norm of the joint angular velocity (NJAV), 3D Euler angular velocity (EAV) and pushing time on the blocks were calculated. The results demonstrated that the decrease of the block spacing induces an opposite effect on the angular velocity of joints of the lower and the upper limbs. The NJAV of the upper limbs is greater in the bunched start, whereas the NJAV of the lower limbs is smaller. The modifications of NJAV were due to a combination of the movement of the joints in the different degrees of freedom. The medium start seems to be the best compromise because it leads, in a short pushing time, to a combination of optimal joint velocities for upper and lower segments.  相似文献   
460.
The purpose of this study was to describe substrate changes in blood and muscles during submaximal exercise and to look at the relationship of these changes to some enzyme activities important in lipid and carbohydrate metabolism. A group of six trained and six untrained men were exercised for 1 hour at 50% [Vdot]O2 max; three from each group cycled and the rest ran on a treadmill. During the exercise, blood-free fatty acid (FFA) levels increased twofold, glycerol by 3.6 times, triglyceride (TG) by 11/100 ml, and glucose by a mean 11 mg/100 ml in the trained men. In the untrained subjects, however, FFA increased 1.8 fold, glycerols 1.6 fold, and TG by a mean 24/100 ml. Glucose fell in every subject by an average 5 mg%. Muscle glycogen depletion averaged 34 mmoles/kg in the untrained and 23 mmoles/kg in the trained group. The activities of succinic acid dehydrogenase (SDH), malic acid dehydrogenase (MDH), and carnitine palmityl transferase (CPT) were greater by 177%, 93%, and 64%, respectively, in the trained group than in the untrained subjects. The results indicated that at the same percent [Vdot]O2 max, the trained men seemed to “preferentially” use FFA as an energy source, possibly due to a well developed Krebs cycle and increased CPT activities. This preference would tend to inhibit the major rate-limiting enzymes of glycolysis, thus slowing even further the use of carbohydrates as an energy source. The differences in response to exercise were independent of fiber type and indicate that these catabolic responses were primarily due to aerobic training.  相似文献   
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