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31.
Abstract

The present study aimed to examine the potential importance of orthographic flexibility for Chinese reading acquisition. Orthographic flexibility is a novel concept that represents the ability to manage and switch attention among multiple aspects of orthographic information. A total of 92 Chinese kindergarten children at age 6 were assessed on measures of orthographic flexibility, orthographic knowledge, executive functions (EF) skills (i.e. cognitive flexibility and working memory) and Chinese word reading. Results of hierarchical regressions showed that orthographic flexibility uniquely and significantly contributed to word reading beyond the effects of established predictors, namely orthographic knowledge and EF skills. Path analysis further indicated that orthographic flexibility significantly mediated the contribution of EF skills to word reading. These findings provided theoretical insights into the linkage between domain-general EF skills and domain-specific reading ability. The present study also provided practical implication that training on orthographic flexibility in addition to orthographic knowledge could be beneficial to early acquisition of Chinese word reading.  相似文献   
32.
Student reflective ideas were examined with respect to Group Investigation (GI), which was employed in 11th grade Korean earth science classrooms. A modified GI method was implemented during the course of an action research effort consisting of two yearlong projects. Students’ writings, which had been produced twice a year, were analyzed to reveal their reflections concerning the GI method. The students were positive about how GI altered the ways their learning occurred in the classrooms. They also reported several positive learning outcomes resulting from the GI implementation. However, there were some students who considered the GI method inappropriate for them. At times, students had difficulties and experienced problems arising from implementing GI. Implications for use of cooperative inquiry learning methods in science classrooms are elaborated on and discussed.  相似文献   
33.
International Journal for Educational and Vocational Guidance - This study provides insights into how Chinese adolescents in Hong Kong interpret the concept of “meaning in life.” Data...  相似文献   
34.
The present study examined the types of orthographic knowledge that are important in learning to read and spell Chinese words in a 2‐year longitudinal study following 289 Hong Kong Chinese children from Grade 1 to Grade 2. Multiple regression results showed that radical knowledge significantly predicted children's word reading and spelling performance across the years. Stroke knowledge contributed both concurrently (Grade 1) and longitudinally (Grade 2) to children's spelling performance after controlling for rapid naming, phonological awareness, morphological awareness and radical knowledge. These findings support the significance of radical knowledge in Chinese reading and spelling and the specific role of stroke order knowledge in Chinese spelling. The findings have implications for the design of an effective curriculum for teaching children to spell Chinese characters.  相似文献   
35.
从感染“黑鳃病”的对虾中,分离出一珠对虾的致病菌,经鉴定为蜡伏芽孢杆菌。通过鳃部吸附及肌注感染,受感染的对虾迅速死亡,注射该菌株的培养上清液,对虾也迅速死亡,显示蜡状芽孢杆菌的胞外代谢物,在对虾致病过程中起着重要作用。  相似文献   
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This work proposes the use of charged droplets driven by the Coulombic force as solution-phase reaction chambers for biological microreactions. A droplet can be charged near an electrode under dc voltage by direct contact to the electrode. This process is called electrical charging of droplet (ECOD). This charged droplet can then be transported rapidly between electrodes following the arc of an electric field line by exploiting electrostatic force. As on-demand electrocoalescence, both alkalization of phenolphthalein and bioluminescence reaction of luciferase in the presence of adenosine triphosphate are studied to test the feasibility of the biochemical microreactors using ECOD. Two oppositely charged droplets are merged to have a color change immediately after microchemical reaction. The applicability of an ECOD-driven droplet to measurement of glucose concentration is also tested. The glucose concentration is measured using a colorimetric enzyme-kinetic method based on Trinder’s reaction [J. Clin. Pathol. 22, 158 (1969)]. The color change in the merged droplet is detected with an absorbance measurement system consisting of a photodiode and a light emitting diode.  相似文献   
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39.
We present a hybrid magnetic/size-sorting (HMSS) chip for isolation and molecular analyses of circulating tumor cells (CTCs). The chip employs both negative and positive cell selection in order to provide high throughput, unbiased CTC enrichment. Specifically, the system utilizes a self-assembled magnet to generate high magnetic forces and a weir-style structure for cell sorting. The resulting device thus can perform multiple functions, including magnetic depletion, size-selective cell capture, and on-chip molecular staining. With such capacities, the HMSS device allowed one-step CTC isolation and single cell detection from whole blood, tested with spiked cancer cells. The system further facilitated the study of individual CTCs for heterogeneity in molecular marker expression.Circulating tumor cells (CTCs) have emerged as an important biomarker in clinical practice as well as in fundamental research.1, 2 CTCs, shed from primary tumors, have been shown to be an early harbinger of tumor expansion and metastasis3 and have been used to predict disease progression, response to treatment, relapse, and overall survival.4, 5, 6 Recent work has shown that CTCs display distinct proteomic and genetic profiles; for example, CTCs in pancreatic cancer, have increased RNA expression of Wnt, implicating this pathway in metastasis.7 Proteomic characterization of proliferative markers such as Ki-67, and hormonal markers such as androgen receptor in prostate cancer, also have been shown to be predictive of treatment outcome.8, 9Despite such clinical potential of CTCs, their routine detection and characterization still remains a significant technical challenge.10 The task requires screening of a large number of cells (e.g., > 107 cells in 10 ml blood) and enrichment of heterogeneous targets against a complex biological background. Two main methods of CTC isolation are typically used: positive and negative selection. In positive selection, CTCs are directly isolated from blood via size-based filtration11, 12, 13, 14, 15, 16, 17, 18, 19, 20 or antibody-based capture.1, 8, 21 Negative depletion reduces abundant blood cells, often by immunomagnetic separation, for downstream CTC enrichment.22 Both approaches have been used for high throughput CTC isolation from whole blood (SI Table 1).23 Each method, however, has its own inherent limitations. Positive enrichment could be biased by its selection criteria (e.g., cell size and cell surface markers). Negative selection, albeit unbiased, often requires complex sample processing (e.g., multiple washing steps for CTC isolation) that could result in cell loss.We hypothesized that both positive and negative selection could be combined in a single platform to enable (1) highly efficient and unbiased CTC purification, and (2) in-situ molecular analyses of collected cells. As a proof-of-concept, we herein describe a hybrid magnetic/size-sorting (HMSS) system that integrates magnetic and size-based isolation into a compact microfluidic chip. The HMSS first uses a magnetic filter to deplete leukocytes through immunomagnetic capture. Samples then pass through a size-sorter region that traps individual cells at predefined locations. Since abundant leukocytes are removed by the magnetic filter, the size-sorter could have a low size cut-off (∼5 μm), which allows for the unbiased capture of even small cancer cells. Furthermore, molecular probes can be introduced to perform on-chip, multiplexed analyses at single-cell resolution. We evaluated the utility of the developed system by capturing and profiling tumor cells in whole blood. The HMSS offers the advantages of both negative and positive selection and thereby differs from the recently reported iChip system24 which can operate only in either a negative or a positive selection mode.  相似文献   
40.
Popular media such as films, television programmes/commercials and magazines have become the dominant source through which children learn about others and their world, develop attitudes and beliefs as manifested in media expressions, and formulate their sense of identity. Popular media have enormous influence on children who are constantly immersing themselves in value‐laden media images that perpetuate over‐generalised representations of cultural groups, in particular, lesbian and gay stereotypes. By critically examining media images in the art room, media literacy art education offers art teachers and their students an opportunity to nurture their aesthetic sensibilities, social awareness and the media literacy necessary to resist and challenge prejudiced, dehumanised or unjust social practices. This article explores issues of lesbian and gay stereotypes in the media, and proposes using media images as a pedagogical device to help students deconstruct them.  相似文献   
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