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21.
Albanian is an Indo-European language with a shallow orthography, in which there is an absolute correspondence between graphemes and phonemes. We aimed to know reading strategies used by Albanian disabled children during word and pseudoword reading. A pool of 114 Kosovar reading disabled children matched with 150 normal readers aged 6 to 11?years old were tested. They had to read 120 stimuli varied in lexicality, frequency, and length. The results in terms of reading accuracy as well as in reading times show that both groups were affected by lexicality and length effects. In both groups, length and lexicality effects were significantly modulated by school year being greater in early grades and later diminish in length and just the opposite in lexicality. However, the reading difficulties group was less accurate and slower than the control group across all school grades. Analyses of the error patterns showed that phonological errors, when the letter replacement leading to new nonwords, are the most common error type in both groups, although as grade rises, visual errors and lexicalizations increased more in the control group than the reading difficulties group. These findings suggest that Albanian normal children use both routes (lexical and sublexical) from the beginning of reading despite of the complete regularity of Albanian, while children with reading difficulties start using sublexical reading and the lexical reading takes more time to acquire, but finally both routes are functional. 相似文献
22.
深层对话的促成有赖三个时机:个人的批判分析与自我反思、由学术会议所引发的社会讨论、对学术会议中研究报告的再研究以获得心得.在这些时机中,由于参与课程研究的学者得以暂时远离熟悉的本土情境和规范,可以像个陌生人一样去质疑、评论本国和他国的课程事件与问题.因此,课程研究的国际化可以创造超越国家的课程对话空间,并引发知识上的突破. 相似文献
23.
Liu F Zhong H Liang JY Fu P Luo ZJ Zhou L Gou R Huang J 《Journal of Zhejiang University. Science. B》2010,11(12):905-911
In this paper,we investigate the effect and the possible mechanism of high glucose levels on the calcification of human aortic smooth muscle cells (HASMCs).HASMCs were divided into four groups: normal glucose group (NG),osmolality control group (OC),high glucose group (HG,HASMCs culture medium containing 30 mmol/L glucose),and high glucose plus recombinant human Noggin protein (bone morphogenetic protein-2 (BMP-2) antagonist) group (HN).The mRNA levels and the protein expressions of BMP-2 and core binding factor alpha-1 (Cbfα-1) were measured by real-time quantitative polymerase chain reaction (PCR) and Western blot.After induced by 10 mmol/L β-glycerol phosphoric acid,cells were harvested for assessments of alkaline phosphatase (ALP) activities at Days 1,2,and 3,and intracellular calcium contents at Days 7 and 14,respectively.High glucose levels increased the mRNA levels and the protein expressions of BMP-2 and Cbfα-1 (P0.05).The expression of Cbfα-1 was partially blocked by Noggin protein (P0.05),while BMP-2 was not (P0.05).After being induced by β-glycerol phosphoric acid,high glucose levels increased the ALP activity [(48.63±1.03) vs.(41.42±2.28) U/mg protein,Day 3;P0.05] and the intracellular calcium content [(2.76±0.09) vs.(1.75±0.07) μmol/mg protein,Day 14;P0.05] in a time-dependent manner when compared with the NG group,while the ALP activity could not be blocked by Noggin protein [(48.63±1.03) vs.(47.37±0.97) U/mg protein,Day 3;P0.05].These results show that high glucose levels can evoke the calcification of HASMCs by inducing osteoblastic trans-differentiation and intracellular calcium deposition via the BMP-2/Cbfα-1 pathway,which can be partially blocked by Noggin protein. 相似文献
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In this paper, a detailed numerical and experimental investigation into the optimisation of hydrodynamic micro-trapping arrays for high-throughput capture of single polystyrene (PS) microparticles and three different types of live cells at trapping times of 30 min or less is described. Four different trap geometries (triangular, square, conical, and elliptical) were investigated within three different device generations, in which device architecture, channel geometry, inter-trap spacing, trap size, and trap density were varied. Numerical simulation confirmed that (1) the calculated device dimensions permitted partitioned flow between the main channel and the trap channel, and further, preferential flow through the trap channel in the absence of any obstruction; (2) different trap shapes, all having the same dimensional parameters in terms of depth, trapping channel lengths and widths, main channel lengths and widths, produce contrasting streamline plots and that the interaction of the fluid with the different geometries can produce areas of stagnated flow or distorted field lines; and (3) that once trapped, any motion of the trapped particle or cell or a shift in its configuration within the trap can result in significant increases in pressures on the cell surface and variations in the shear stress distribution across the cell’s surface. Numerical outcomes were then validated experimentally in terms of the impact of these variations in device design elements on the percent occupancy of the trapping array (with one or more particles or cells) within these targeted short timeframes. Limitations on obtaining high trap occupancies in the devices were shown to be primarily a result of particle aggregation, channel clogging and the trap aperture size. These limitations could be overcome somewhat by optimisation of these device design elements and other operational variables, such as the average carrier fluid velocity. For example, for the 20 μm polystyrene microparticles, the number of filled traps increased from 32% to 42% during 5–10 min experiments in devices with smaller apertures. Similarly, a 40%–60% reduction in trapping channel size resulted in an increase in the amount of filled traps, from 0% to almost 90% in 10 min, for the human bone marrow derived mesenchymal stem cells, and 15%–85% in 15 min for the human embryonic stem cells. Last, a reduction of the average carrier fluid velocity by 50% resulted in an increase from 80% to 92% occupancy of single algae cells in traps. Interestingly, changes in the physical properties of the species being trapped also had a substantial impact, as regardless of the trap shape, higher percent occupancies were observed with cells compared to single PS microparticles in the same device, even though they are of approximately the same size. This investigation showed that in microfluidic single cell capture arrays, the trap shape that maximizes cell viability is not necessarily the most efficient for high-speed single cell capture. However, high-speed trapping configurations for delicate mammalian cells are possible but must be optimised for each cell type and designed principally in accordance with the trap size to cell size ratio. 相似文献
26.
This article reports on a one-semester Advanced Cell Biology course that endeavors to bridge the gap between gaining basic textbook knowledge about cell biology and learning to think and work as a researcher. The key elements of this course are 1) learning to work with primary articles in order to get acquainted with the field of choice, to learn scientific reasoning, and to identify gaps in our current knowledge that represent opportunities for further research; 2) formulating a research project with fellow students; 3) gaining thorough knowledge of relevant methodology and technologies used within the field of cell biology; 4) developing cooperation and leadership skills; and 5) presenting and defending research projects before a jury of experts. The course activities were student centered and focused on designing a genuine research program. Our 5-yr experience with this course demonstrates that 1) undergraduate students are capable of delivering high-quality research designs that meet professional standards, and 2) the authenticity of the learning environment in this course strongly engages students to become self-directed and critical thinkers. We hope to provide colleagues with an example of a course that encourages and stimulates students to develop essential research thinking skills. 相似文献
27.
Henderson E Kinzett S Lockwood F 《British journal of educational technology : journal of the Council for Educational Technology》1988,19(3):184-192
Collaboration between subject matter specialists, computer programmers and educational technologists has resulted in the production of POPTRAN, a computer assisted learning package designed to teach the basic concepts of population studies. Its evaluation in developing countries, with both naive and specialist users, and subsequent revision, has produced a package of both academic quality and teaching effectiveness. 相似文献
28.
ThetoleranceofthemudskipperBoleophthalmusboddaertitocyanideishigherthanthoseofotherfishes[1].Suchahightolerancetocyanidedoesnotinvoveareductionofmetabolicrateoranenhancedanaerobicmetabolism,oracyanide-insensitiverespiratorypathway.Instead,itisaresultofthepresenceofasurplusofcytochromeoxidaseandinduciblecyanide-detoxifyingmechanisms,tumingcyanideinthiocyanate,inthismudskipper[1].ThoughCN-isdetoxifiedtoSCN-,realizingbiomembranesaremorepermeabletoHCNthanCN-,wedecidedtoinvestigateiftheprotondi… 相似文献
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30.
The aim of this study was to determine the level of awareness of methodological search filters among health and academic librarians in the UK and Ireland, their use of filters and views on the perceived benefits, limitations and ways to increase usage of search filters. A random proportional sample of health and academic librarians were surveyed by telephone and fax. Overall, 88% (196/224) completed the telephone survey to establish awareness and use of filters. Eighty-four per cent (51/61) completed a fax survey focusing in more depth on usability issues surrounding filters. Results indicate a high level of awareness of methodological filters, but low level of usage. Furthermore, a high level of awareness did not necessarily correlate with a high level of knowledge or understanding. Examination of responses revealed limitations and recommendations beyond those reported in the literature and highlights the relationship between understanding and effective use of filters. Improved dissemination and publication of filters is required to better inform librarians on the concept of filters and how to use them effectively. 相似文献