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991.
The contribution of children’s self-regulation and classroom quality to children’s adaptive behaviors in the kindergarten classroom. 总被引:5,自引:0,他引:5
Rimm-Kaufman Sara E.; Curby Tim W.; Grimm Kevin J.; Nathanson Lori; Brock Laura L. 《Canadian Metallurgical Quarterly》2009,45(4):958
In this study, the authors examined the extent to which children’s self-regulation upon kindergarten entrance and classroom quality in kindergarten contributed to children’s adaptive classroom behavior. Children’s self-regulation was assessed using a direct assessment upon entrance into kindergarten. Classroom quality was measured on the basis of multiple classroom observations during the kindergarten year. Children’s adaptive classroom behavior in kindergarten was assessed through teacher report and classroom observations: Teachers rated children’s cognitive and behavioral self-control and work habits during the spring of the kindergarten year; observers rated children’s engagement and measured off-task behavior at 2-month intervals from November to May. Hierarchical linear models revealed that children’s self-regulation upon school entry in a direct assessment related to teachers’ report of behavioral self-control, cognitive self-control, and work habits in the spring of the kindergarten year. Classroom quality, particularly teachers’ effective classroom management, was linked to children’s greater behavioral and cognitive self-control, children’s higher behavioral engagement, and less time spent off-task in the classroom. Classroom quality did not moderate the relation between children’s self-regulation upon school entry and children’s adaptive classroom behaviors in kindergarten. The discussion considers the implications of classroom management for supporting children’s early development of behavioral skills that are important in school settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Newcombe Nora S.; Ambady Nalini; Eccles Jacquelynne; Gomez Louis; Klahr David; Linn Marcia; Miller Kevin; Mix Kelly 《Canadian Metallurgical Quarterly》2009,64(6):538
Improving mathematics and science education in the United States has been a matter of national concern for over half a century. Psychology has a vital role to play in this enterprise. In this article, the authors review the kinds of contributions that psychology can make in four areas: (a) early understanding of mathematics, (b) understanding of science, (c) social and motivational aspects of involvement in mathematics and science, and (d) assessment of learning in mathematics and science. They also examine challenges to psychology’s playing a central and constructive role and make recommendations for overcoming those challenges. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
The potential association between psychosis and violence to others has long been debated. Past research findings are mixed and appear to depend on numerous potential moderators. As such, the authors conducted a quantitative review (meta-analysis) of research on the association between psychosis and violence. A total of 885 effect sizes (odds ratios) were calculated or estimated from 204 studies on the basis of 166 independent data sets. The central tendency (median) of the effect sizes indicated that psychosis was significantly associated with a 49%–68% increase in the odds of violence. However, there was substantial dispersion among effect sizes. Moderation analyses indicated that the dispersion was attributable in part to methodological factors, such as study design (e.g., community vs. institutional samples), definition and measurement of psychosis (e.g., diagnostic vs. symptom-level measurement, type of symptom), and comparison group (e.g., psychosis compared with externalizing vs. internalizing vs. no mental disorder). The authors discuss these findings in light of potential causal models of the association between psychosis and violence, the role of psychosis in violence risk assessment and management, and recommendations for future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Kevin Kennon 《Architectural Design》2006,76(5):50-53
Bringing together a number of design celebrities, among them Greg Lynn, UN Studio, Foreign Office Architects (FOA) and Kevin Kennon Architect, United Architects (UA) was established to create a collaborative proposal for the 2003 competition for a new World Trade Center. Invoking the name as well as the intentions of what started as a similar collaborative formation by established actors and film-makers in the 1940s (United Artists) to challenge mainstream corporate power, UA attempted to offer more visionary alternatives to the expectations of typical mainstream architectural solutions. Kevin Kennon here presents an insider's perspective on the UA collaboration and employs his unique history, including his former partnership at Kohn Pedersen Fox (KPF) to raise important questions about collective design in terms of authorship, identity and practice. Central to his observations are the differences between the efficiency models of corporate teams and truly collaborative endeavours. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
995.
Stream quality in a small urbanised catchment 总被引:1,自引:0,他引:1
River-length patterns in the chemistry and biology of the Charlton Brook, an unclassified watercourse in Sheffield, England, have been examined. Five sampling sites for macroinvertebrates and pollutant analysis were used, in conjunction with Environment Agency's General Quality Assessment (GQA) methodologies and hydraulic analysis of the catchment. Sites were strategically located to account for the tributaries and the brook downstream of their confluence, to assess the potential impact from surface water outfalls (SWOs). Variations in GQA parameters indicate a significant drop in quality downstream of the SWOs that discharge to the study watercourse, with a marked drop in biological diversity noted at the onset of urbanisation. The decline in biological quality however is greater than that suggested by physicochemical analysis alone. There was a significant inverse relationship between impermeable area and biological diversity. Analysis of polycyclic aromatic hydrocarbons (PAHs) and trace metals in sediment from the watercourse showed significant yet irregular variations between sites. The potential toxicity of instream metal concentrations was determined using cumulative criterion unit (CCU) scores, which highlighted cadmium, copper and lead as the major sources of potential chronic instream toxicity. The threshold for likely harm to aquatic life is exceeded at all sites. In the absence of different physical characteristics, comparisons of the chemical and biological data indicate that the benthic macroinvertebrate population of such watercourses are adversely affected by the stormwater inputs. 相似文献
996.
Integrated understanding of urban land, groundwater (shallow and deep), baseflow and surface-water quality relationships is required for effective urban water-quality management. Chemical quality data from across these media have been collected for the Birmingham (UK) aquifer--River Tame conurbation to assess chemical transport from contaminated land to groundwater to baseflow to surface water. Although metals concentrations were high in soils, low leachability and attenuation caused concentrations in groundwaters and baseflow discharging to surface water to be generally low with only sporadic elevated concentrations attributed to localised point sources. Hydrocarbon VOCs (volatile organic compounds) were similarly absent or at low concentration attributable to their ready natural attenuation. Chlorinated VOCs, however, were widely encountered in groundwater, discharging as baseflow to surface water and impacting surface-water quality. This is attributed to their DNAPL (dense nonaqueous-phase liquid) properties and relative recalcitrance although there was some evidence of biodegradation, albeit insufficient to protect surface water and groundwater abstraction receptors. Some inorganic trends were evident across the various media; nitrate was the most significant quality concern. Generic conclusions are drawn on urban water-quality management and the need for risk-based management strategies to optimise use of urban, sporadically contaminated groundwater in conjunction with surface water highlighted. 相似文献
997.
Ben Leslie Peter Chubb Nicholas Fitzroy-Dale StefanGotz Charles Gray Luke Macpherson Daniel Potts Yue-Ting Shen and Kevin Elphinstone 《计算机科学技术学报》2005,20(5):654-664
Running device drivers as unprivileged user-level code, encapsulated into their own process, has often been proposed as a technique for increasing system robustness. However, in the past, systems based on user-level drivers have generally exhibited poor I/O performance. Consequently, user-level device drivers have never caught on to any significant degree. In this paper we demonstrate that it is possible to build systems which employ user-level device drivers, without significant performance degradation, even for high-bandwidth devices such as Gigabit Ethernet. 相似文献
998.
Wang H Wingett D Engelhard MH Feris K Reddy KM Turner P Layne J Hanley C Bell J Tenne D Wang C Punnoose A 《Journal of materials science. Materials in medicine》2009,20(1):11-22
Fluorescein isothiocyanate (FITC)-encapsulated SiO2 core-shell particles with a nanoscale ZnO finishing layer have been synthesized for the first time as multifunctional “smart”
nanostructures. Detailed characterization studies confirmed the formation of an outer ZnO layer on the SiO2–FITC core. These ~200 nm sized particles showed promise toward cell imaging and cellular uptake studies using the bacterium
Escherichia coli and Jurkat cancer cells, respectively. The FITC encapsulated ZnO particles demonstrated excellent selectivity in preferentially
killing Jurkat cancer cells with minimal toxicity to normal primary immune cells (18% and 75% viability remaining, respectively,
after exposure to 60 μg/ml) and inhibited the growth of both gram-positive and gram-negative bacteria at concentrations ≥250–500 μg/ml
(for Staphylococcus aureus and Escherichia coli, respectively). These results indicate that the novel FITC encapsulated multifunctional particles with nanoscale ZnO surface
layer can be used as smart nanostructures for particle tracking, cell imaging, antibacterial treatments and cancer therapy. 相似文献
999.
1000.
设计研制了一种新型的低噪声分布式放大器,采用了栅长为1μm的低噪声复合沟道Al0.3Ga0.7N/Al0.05Ga0.95N/GaN HEMT(CC-HEMT).给出了低噪声分布式放大器的仿真和测试结果.测试结果显示低噪声分布式放大器在2~10GHz频率范围内,输入和输出端口驻波比均小于2.0,相关增益大于7.0dB.带内增益波纹小于1d8.在2~6GHz频率范围内,噪声系数小于5dB;在2~10GHz频率范围内,噪声系数小于6.5dB;测试结果与仿真结果较吻合. 相似文献