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181.
The importance of reading fluently is widely recognized in school effectiveness, reform, and improvement efforts of the educational community, yet there are few large-scale, structured assessments of the progression of students' reading rates over time. This study documented 2nd-grade students' oral reading rates on the basis of fall, winter, and spring assessments. Using growth curve analysis, we identified models for a sample (n = 5,796) of students in 79 schools in a large urban school district in the United States. We found that, although school characteristics were significant predictors of the children's initial oral reading status, they were mostly not significant predictors of their reading rate over time. At the individual level, girls had a better performance than did boys in reading achievement testing, and no statistically significant difference was noted between boys and girls in their growth rates during the 2nd grade. On the other hand, special education children not only achieved less than did non-special education children in oral reading but also evidenced a significantly lower rate of increase. The trustworthiness of “at risk” and “low risk” instructional recommendations on the basis of oral reading rates was high. We discuss these findings in light of the existing research on reading fluency. Our findings have implications for research and instruction for fluency and literacy development of both fluent and nonfluent readers. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
182.
Park SI Kwon BJ Park JH Jung H Yu KH 《Journal of nanoscience and nanotechnology》2011,11(2):1818-1821
In this study, we have successfully developed 3-[131I]iodo-tyrosine grafted Fe3O4@SiO2 nanocomposites for dual potential tumor imaging agent for SPECT and MRI. Fe3O4 nanoparticle was synthesized through thermal decomposition and Fe3O4@SiO2 was prepared by reverse microemulsion method. After conjugating aminopropyltriethoxysiliane, L-tyrosine was introduced by amide coupling reaction. Finally, [131I]iodide was labeled on L-tyrosine grafted Fe3O4@SiO2 nanocomposite by aromatic iodination using chloramine-T. 相似文献
183.
Bob Brader Rachel C LeeRudy Plarre Wendell BurkholderG.Barrie Kitto Chuan Kao Lynn PolstonEleanora Dorneanu Ioana SzaboBill Mead Bob RouseDon Sullins Royal Denning 《Journal of Stored Products Research》2002,38(1):75-86
In collaboration with the United States Department of Agriculture and a number of major milling companies, the “Insect-Detect” immunoassay for analyzing insect contamination in grains has been compared with three more traditional methods, X-ray analysis, cracking and flotation, and the insect fragment test (IFT). Testing was carried out in blind fashion using clean wheat samples that were spiked with differing numbers of grain kernels infested with late instar larvae of the granary weevil (Sitophilus granarius (L.)). Three different laboratories analyzed the samples for each of the four methods. The collaborative trials showed that the insect immunoassay clearly provided the most accurate measurement of actual insect infestation, followed by X-ray analysis. While both cracking and flotation and IFT procedures provided a general measure of contamination, they showed much greater variability. 相似文献
184.
185.
Minos Esperândio Carvalho Gustavo Gasparin Mirele Daiana Poleti Alessandra Fernandes Rosa Júlio Cesar Carvalho Balieiro Carlos Alberto Labate Renata Tieko Nassu Rymer Ramiz Tullio Luciana Correia de Almeida Regitano Gerson Barreto Mourão Luiz Lehmann Coutinho 《Meat science》2014
Nellore beef cattle, a Bos indicus (Zebu) breed, is well adapted to tropical conditions and has allowed Brazil to become one of the largest producers of red meat. Nevertheless, B. indicus breeds are reported to have less tender meat than Bos taurus. This study was designed to identify genes associated with meat tenderness and thus provides important information for breeding programs. A group of 138 animals was evaluated for longissimus thoracis muscle shear force (SF). Animals with the highest and lowest SF values (six animals each) were then selected for protein abundance studies. Samples were subjected to two-dimensional gel electrophoresis (2-DE) followed by peptide sequencing through mass spectrometry (MS) to identify differentially expressed proteins associated with SF values. Seventeen differentially expressed spots were observed (p < 0.05) between the two groups. The 13 proteins identified included structural proteins (alpha actin-1, MLC1, MLC3, MLC2F and tropomyosin), related to cell organization (HSPB1 and HSP70), metabolism (beta-LG, ACBD6 and Complex III subunit I) and some uncharacterized proteins. Results confirm the existence of differentially expressed proteins associated with SF, which can lead to a better understanding of mechanisms involved in meat tenderness. 相似文献
186.
Hierarchical polymer composites – defined as carbon nanofiber/fiber-reinforced polymer composites – were manufactured using multiscale-reinforcement fabrics (MRFs) and they were characterized for their mechanical properties. The MRFs were fabricated by electrophoretic deposition of carboxylic acid- or amine-functionalized carbon nanofibers (CNFs) on the surface of sized or unsized carbon fiber layers. Compared to the base composite (not containing CNFs), the hierarchical composites containing the functionalized CNFs showed an increase in interlaminar shear strength (ILSS) and compressive strength. Panels containing amine-functionalized CNFs had the highest increase in properties: 12% in ILSS and 13% in compressive strength. The reinforcement mechanism was also investigated with emphasis placed on the fiber/matrix interface and the load transfer between matrix, CNFs, and carbon fiber. 相似文献
187.
Xu-Liang Cao Jiping Zhu Stephen MacDonald Kaela Lalonde Bob Dabeka Mamady Cisse 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(6):808-813
An isotope dilution method based on solvent extraction followed by GC–MS analysis was developed and used to determine aniline in vegetable and fruit samples collected from the Canadian total diet study. Aniline was not detected in any of the 23 vegetable samples from the 2005 total diet study at a method detection limit of 0.01 mg kg–1. Among the 16 fruit samples, it was detected only in apple samples, with an average concentration of 0.278 mg kg–1. Aniline was not detected in apple samples collected in the 2002, 2003, 2006 or 2007 total diet studies, but it was detected in the apple samples collected from the 2001 and 2004 studies, at concentrations of 0.085 and 0.468 mg kg–1, respectively. The average aniline concentration for the 2001, 2004 and 2005 apple samples was 0.277 mg kg–1. Good repeatability of the method was observed with replicate analysis of apple samples, with relative standard deviations (RSD) ranging 3.8–21% and an average of 11%. 相似文献
188.
Gerson Henrique dos Santos Nathan Mendes 《International Journal of Heat and Mass Transfer》2009,52(9-10):2390-2398
The combined heat, air and moisture transfer in building hollow elements is of paramount importance in the construction area for accurate energy consumption prediction, thermal comfort evaluation, moisture growth risk assessment and material deterioration analysis. In this way, a mathematical model considering the combined two-dimensional heat, air and moisture transport through unsaturated building hollow bricks is presented. In the brick porous domain, the differential governing equations are based on driving potentials of temperature, moist air pressure and water vapor pressure gradients, while, in the air domain, a lumped approach is considered for modeling the heat and mass transfer through the brick cavity. The discretized algebraic equations are solved using the MTDMA (MultiTriDiagonal-Matrix Algorithm) for the three driving potentials. Comparisons in terms of heat and vapor fluxes at the internal boundary are presented for hollow, massive and insulating brick blocks. Despite most of building energy simulation codes disregard the moisture effect and the transport multidimensional nature, results show those hypotheses may cause great discrepancy on the prediction of hygrothermal building performance. 相似文献
189.
讨论在当前发展的三种无线通信网GSM、GPRS和UMTS中,话音业务所承担的角色,介绍 GSM话音应用的未来。 相似文献
190.
The study of the spontaneous expressions of blind individuals offers a unique opportunity to understand basic processes concerning the emergence and source of facial expressions of emotion. In this study, the authors compared the expressions of congenitally and noncongenitally blind athletes in the 2004 Paralympic Games with each other and with those produced by sighted athletes in the 2004 Olympic Games. The authors also examined how expressions change from 1 context to another. There were no differences between congenitally blind, noncongenitally blind, and sighted athletes, either on the level of individual facial actions or in facial emotion configurations. Blind athletes did produce more overall facial activity, but these were isolated to head and eye movements. The blind athletes' expressions differentiated whether they had won or lost a medal match at 3 different points in time, and there were no cultural differences in expression. These findings provide compelling evidence that the production of spontaneous facial expressions of emotion is not dependent on observational learning but simultaneously demonstrates a learned component to the social management of expressions, even among blind individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献