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981.
982.
Songliang Wang Claude Caldwell Liqing Wei Haiyan Su 《Frontiers of Education in China》2015,10(3):427-438
The Fujian Agriculture and Forestry University-Nova Scotia Agricultural College (FAFU-NSAC) 2 + 2 undergraduate program initiated in 2003 is a model for creative collaboration between China and Canada in undergraduate education. This paper addresses the achievements of the program development and highlights the process for successful curriculum development in the joint program. The authors also discuss some issues and challenges related to the Chinese-Canadian experience in undergraduate education, and propose some recommendations for further collaborations including: enlarging the scale of qualified programs; proposing a systematic baseline to control the program at a macro-level; simplifying coordination procedures with foreign partners; and adjusting the emphasis of courses introduced by the cooperative partner from quantity to quality. 相似文献
983.
This study investigates 1.5 generation1 Asian immigrant children’s (n = 264) early literacy achievement patterns, treating them as a heterogeneous group. Specifically, the within-group variances in reading achievement from kindergarten to third grade are examined, drawing on four waves of data from the ECLS-K class of 1998–1999. Our analysis shows that ethnicity plays a role in shaping the children’s initial reading readiness and later growth, but the effects of languages spoken at home are not significant. Our analysis also demonstrates a persistent achievement gap between low- and high-socioeconomic status (SES) Asian groups. However, gender difference in terms of children’s reading development is not found to be significant. There is also no interaction between SES and the other factors such as gender, ethnicity and language backgrounds. 相似文献
984.
985.
The development of ovarian follicular cells is controlled by multiple circulating and local hormones and factors, including
follicle-stimulating hormone (FSH) and epidermal growth factor (EGF). In this study, the stage-specific effect of EGF on FSH-induced
proliferation of granulosa cells was evaluated in the ovarian follicles of egg-laying chickens. Results showed that EGF and its receptor (EGFR) mRNAs displayed a high expression in granulosa cells from the prehierarchical follicles, including the large white follicle
(LWF) and small yellow follicle (SYF), and thereafter the expression decreased markedly to the stage of the largest preovulatory
follicle. SYF represents a turning point of EGF/EGFR mRNA expression during follicle selection. Subsequently the granulosa cells from SYF were cultured to reveal the mediation
of EGF in FSH action. Cell proliferation was remarkably increased by treatment with either EGF or FSH (0.1–100 ng/ml). This
result was confirmed by elevated proliferating cell nuclear antigen (PCNA) expression and decreased cell apoptosis. Furthermore,
EGF-induced cell proliferation was accompanied by increased mRNA expressions of EGFR, FSH receptor, and the cell cycle-regulating
genes (cyclins D1 and E1, cyclin-dependent kinases 2 and 6) as well as decreased expression of luteinizing hormone receptor
mRNA. However, the EGF or FSH-elicited effect was reversed by simultaneous treatment with an EGFR inhibitor AG1478. In conclusion,
EGF and EGFR expressions manifested stage-specific changes during follicular development and EGF mediated FSH-induced cell
proliferation and retarded cell differentiation in the prehierarchical follicles. These expressions thus stimulated follicular
growth before selection in the egg-laying chicken. 相似文献
986.
Gas-liquid coupling oscillation is a novel approach to reducing the resonant frequency and to elevating the pressure amplitude
of a thermoacoustic engine. If a thermoacoustic engine is used to drive low-frequency pulse tube refrigerators, the frequency
matching between the thermoacoustic engine and the refrigerator plays an important role. Based on an acoustic-electric analogy,
a lumped parameter model is proposed to estimate the resonant frequency of a standing-wave thermoacoustic engine with gas-liquid
coupling oscillation. Furthermore, a simplified lumped parameter model is also developed to reduce the computation complexity.
The resonant frequency dependence on the mean pressure, the gas space volume, and the water column length is computed and
analyzed. The impact of different working gases on the resonant frequency is also discussed. The effectiveness of the models
is validated by comparing the computed results with the experimental data of the gas-liquid coupling oscillation system. An
increase in the mean working pressure can lead to a rise in the resonant frequency, and a lower resonant frequency can be
achieved by elongating the liquid column. In comparison with nitrogen and argon, carbon dioxide can realize a lower frequency
due to a smaller specific heat ratio. 相似文献
987.
Cornelia A. T. Kegel Adriana G. Bus Marinus H. van IJzendoorn 《Mind, Brain, and Education》2011,5(2):71-78
Not every child seems equally susceptible to the same parental, educational, or environmental influences even if cognitive level is similar. This study is the first randomized controlled trial to apply the differential susceptibility paradigm to education in relation to children's genotype and early literacy skills. A randomized pretest–posttest control group design was used to examine the effects of the Intelligent Tutoring System Living Letters. Two intervention groups were created, 1 receiving feedback and 1 completing the program without feedback, and 1 control group. Carriers of the long variant of the dopamine D4 receptor gene (DRD4 7‐repeat) profited most from the computer program with positive feedback, whereas they performed at the lowest level of early literacy skills in the absence of such feedback. Our findings suggest that behind modest overall educational intervention effects a strong effect on a subgroup of susceptible children may be hidden. 相似文献
988.
大多数的人总是倾向于临渴挖井而非居安思危,总觉得那些不幸之事不会降临到自己身上,但是大家有没有想过,也许有一天躺在病床上苦苦等待别人救助的会变成我们自己或者我们亲友?我是那些幸运儿之一,现在轮到我去帮助别人了。我最近进行了一次奇妙的旅行,刚从南非的德班回来,我在那里参加了第19届世界移植运动会。自1996年起,我就一直有参加这个移植运动会。无论怎么看,我 相似文献
989.
Sammy Perone Stephen J. Molitor Aaron T. Buss John P. Spencer Larissa K. Samuelson 《Child development》2015,86(3):812-827
Executive functions enable flexible thinking, something young children are notoriously bad at. For instance, in the dimensional change card sort (DCCS) task, 3‐year‐olds can sort cards by one dimension (shape), but continue to sort by this dimension when asked to switch (to color). This study tests a prediction of a dynamic neural field model that prior experience with the postswitch dimension can enhance 3‐year‐olds' performance in the DCCS. In Experiment 1A, a matching game was used to preexpose 3‐year‐olds (n = 36) to color. This facilitated switching from sorting by shape to color. In 3 , 3‐year‐olds (n = 18) were preexposed to shape. This did not facilitate switching from sorting by color to shape. The model was used to explain this asymmetry. 相似文献
990.