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31.
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   
32.
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   
33.
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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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   
36.
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   
37.
信息不完善是高等教育市场失灵的一个重要表现。我国民办高等教育的发展基本是以市场为主导,需求者对信息了解的准确性与全面性将对民办高等教育的健康发展具有重要意义。本文以对全国四个省市10513名高三学生的调查为基础,分析我国高中生对民办高等教育的信息了解状况,以期从信息的角度为民办高等教育的健康发展提出建设性意见。  相似文献   
38.
The technical adequacy of CBM maze-scores as indicators of reading level and growth for seventh-grade secondary-school students was examined. Participants were 452 Dutch students who completed weekly maze measures over a period of 23 weeks. Criterion measures were school level, dyslexia status, scores and growth on a standardized reading test. Results supported the technical adequacy of maze scores as indicators of reading level and growth. Alternate-form reliability coefficients were significant and intermediate to high. Mean maze scores showed significant increase over time, students’ growth trajectories differed, and students’ initial performance levels (intercepts) and growth rates (slopes) were not correlated. Maze reading level and growth were related to reading level and/or growth on criterion measures. A nonlinear model provided a better fit for the data than a linear model. Implications for use of CBM maze-scores for data-based decision-making are discussed.  相似文献   
39.
The authors wish to express appreciation for the statistical help provided by James Wardrop and Ya-Mei Chen; and for the support provided by the Bureau of Educational Research and the Campus Research Board, University of Illinois. Also several persons helped with the development of the measures and data collection including Carole Ames, Mary Z. Anderson, Cindy Glidden, Fu-lin Y. Lee, Kirsten Peterson, and Barbara Powell. Requests for reprints may be addressed to the first author at the Educational Psychology Department, University of Illinois, 1310 South Sixth St., Champaign, IL 61820.  相似文献   
40.
This study examined language-specific links among auditory processing, linguistic prosody awareness, and Mandarin (L1) and English (L2) word reading in 61 Mandarin-speaking, English-learning children. Three auditory discrimination abilities were measured: pitch contour, pitch interval, and rise time (rate of intensity change at tone onset). Linguistic prosody awareness was measured three ways: Mandarin tone perception, English stress perception, and English stress production. A Chinese character recognition task was the Mandarin L1 reading metric. English L2 word reading was assessed by English real word reading and nonword decoding tasks. The importance of the auditory processing measures to reading was different in the two languages. Pitch contour discrimination predicted Mandarin L1 word reading and rise time discrimination predicted English L2 word reading, after controlling for age and nonverbal IQ. For the prosodic and phonological measures, Mandarin tone perception, but not rhyme awareness, predicted Chinese character recognition after controlling for age and nonverbal IQ. In contrast, English rhyme awareness predicted more unique variance in English real word reading and nonword decoding than did English stress perception and production. Linguistic prosody awareness appears to play a more important role in L1 word reading than phonological awareness; while the reverse seems true for English L2 word reading in Mandarin-speaking children. Taken together, auditory processing, language-specific linguistic prosody awareness, and phonological awareness play different roles in L1/L2 reading, reflecting different prosodic and segmental structures between Mandarin and English.  相似文献   
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