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151.
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Examining Change in Cortisol Patterns During the 10‐Week Transition to a New Child‐Care Setting 下载免费PDF全文
Kristin Bernard Elizabeth Peloso Jean‐Philippe Laurenceau Zhiyong Zhang Mary Dozier 《Child development》2015,86(2):456-471
The transition to out‐of‐home child care brings a number of challenges for children, including complex peer interactions and extended separations from parents. Children often show a midmorning to afternoon rise in cortisol on child‐care days, compared to the typical diurnal decline seen at home. Changes in cortisol were examined in a wide age range of children (N = 168; 1.2 months to 8 years, M = 3.27 years) during the 10‐week transition to a new child‐care setting. Structural equation modeling using latent change scores showed that children experienced an increase in the cortisol rise at child care across the 10‐week transition. Furthermore, child age moderated the difference between home‐ and child‐care cortisol patterns. Findings are placed in a developmental context, and potential implications and future directions are discussed. 相似文献
153.
Effects of an Attachment‐Based Intervention on Child Protective Services–Referred Mothers' Event‐Related Potentials to Children's Emotions 下载免费PDF全文
This study examined the neurobiology of maternal sensitivity to children's emotions among mothers involved with Child Protective Services (CPS) and low‐risk comparison mothers (Mage = 31.6 years). CPS‐referred mothers participated in the Attachment and Biobehavioral Catch‐up (ABC) intervention or a control intervention. Mothers' event‐related potentials (ERPs) were measured while they categorized images of children with crying, laughing, and neutral expressions. CPS‐referred ABC mothers (n = 19) and low‐risk comparison mothers (n = 30) showed a larger enhancement of ERP responses for emotional faces relative to neutral faces than CPS‐referred control mothers (n = 21). Additionally, the magnitude of ERP responses to emotional faces was associated with observed maternal sensitivity. Findings add to the understanding of the neurobiology of deficits in parenting and suggest that these deficits are changeable through a parenting intervention. 相似文献
154.
Jiseok Lim Ouriel Caen Jérémy Vrignon Manfred Konrad Valérie Taly Jean-Christophe Baret 《Biomicrofluidics》2015,9(3)
Droplet-based microfluidic technologies are powerful tools for applications requiring high-throughput, for example, in biochemistry or material sciences. Several systems have been proposed for the high-throughput production of monodisperse emulsions by parallelizing multiple droplet makers. However, these systems have two main limitations: (1) they allow the use of only a single disperse phase; (2) they are based on multiple layer microfabrication techniques. We present here a pipette-and-play solution offering the possibility of manipulating simultaneously 10 different disperse phases on a single layer device. This system allows high-throughput emulsion production using aqueous flow rates of up to 26 ml/h (>110 000 drops/s) leading to emulsions with user-defined complex chemical composition. We demonstrate the multiplex capabilities of our system by measuring the kinetics of β-galactosidase in droplets using nine different concentrations of a fluorogenic substrate. 相似文献
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Bernard D. Steinberg 《Journal of The Franklin Institute》1979,307(3):205-206
The theory of transient operations of synchronous machines—the so called two-reaction theory—was developed during the years 1926–1938. Doherty, Nickle and Park made the first efforts to find a complete theory. The problem then was solved by Kron for a general rotating electrical machine. In this paper the two-axis-model-machine is described using a bond graph. An example is given in which state-space-equations and output-equations are derived from the bond graph. A power-conserving transformation between the electrical quantities of the armature windings of the model machine and those of the real three phase armature windings is developed. This transformation is shown as a displacement modulated transformer structure which is central to the bond graph model. 相似文献
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Bernard Naylor 《Learned Publishing》1997,10(3):199-204
The electronic learned journal of tomorrow is likely to be substantially different from today's print-on-paper precursor. The emphasis will be on accessibility for the individual user and the objective should be to combine the convenience of the local library collection with the organisation and support services typical of a large general collection. Publishers too will need to adopt access and pricing policies which give priority to the convenience of scholars and which acknowledge value-for-money arguments. Extrapolation from some present day trends may be a useful guide to the future. Parallel publishing itself is likely to be a temporary phenomenon, preceding exclusively electronic scholarly publication in many fields. 相似文献