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91.
Research in Higher Education - State financial aid grant programs are commonly categorized as either need-based, merit-based, or both, but their initial eligibility requirements include many more... 相似文献
92.
What happens to writing instructors’ feedback when they use a common rubric and an online tool to respond to student papers in a first-year composition course at a large state university in the United States? To investigate this question, we analyze the 118,611 comments instructors made when responding to 17,433 student essays. Using concordance software to quantify teachers’ use of rubric terms, we found instructors were primarily concerned with global, substantive, higher-order concerns—such as responding to students’ rhetorical situations, use of reason, and organization—rather than lower-order concerns about grammar or formatting. Given past research has determined teachers overemphasize lower-order concerns such as grammar, mechanics, and punctuation (Connors and Lunsford, 1988, Lunsford and Lunsford, 2008, Moxley and Joseph, 1989, Moxley and Joseph, 1992, Schwartz, 1984, Sommers, 1982, Stern and Solomon, 2006), these results may suggest the possibility of a generational shift when it comes to response to student writing. Aggregating teacher commentary, student work, and peer review responses via digital tools and employing concordance software to identify big-data patterns illuminates a new assessment practice for Writing Program Administrators—the practice of Deep Assessment. 相似文献
93.
94.
The purpose of this paper is to compute the Hankel transform Fn(y) of order n of a function f(x) and its inverse transform using rationalized Haar wavelets. The integrand is replaced by its wavelet decomposition. Thus representing Fn(y) as a Fourier-Bessel series with coefficients depending strongly on the local behavior of the function , thereby getting an efficient algorithm for their numerical evaluation. Numerical evaluations of test functions with known analytical Hankel transforms illustrate the proposed algorithm. 相似文献
95.
Gergely Simon Caroline Busch Marco A. B. Andrade Julien Reboud Jonathan M. Cooper Marc P. Y. Desmulliez Mathis O. Riehle Anne L. Bernassau 《Biomicrofluidics》2021,15(1)
Separation and sorting of biological entities (viruses, bacteria, and cells) is a critical step in any microfluidic lab-on-a-chip device. Acoustofluidics platforms have demonstrated their ability to use physical characteristics of cells to perform label-free separation. Bandpass-type sorting methods of medium-sized entities from a mixture have been presented using acoustic techniques; however, they require multiple transducers, lack support for various target populations, can be sensitive to flow variations, or have not been verified for continuous flow sorting of biological cells. To our knowledge, this paper presents the first acoustic bandpass method that overcomes all these limitations and presents an inherently reconfigurable technique with a single transducer pair for stable continuous flow sorting of blood cells. The sorting method is first demonstrated for polystyrene particles of sizes 6, 10, and 14.5 μm in diameter with measured purity and efficiency coefficients above 75 ± 6% and 85 ± 9%, respectively. The sorting strategy was further validated in the separation of red blood cells from white blood cells and 1 μm polystyrene particles with 78 ± 8% efficiency and 74 ± 6% purity, respectively, at a flow rate of at least 1 μl/min, enabling to process finger prick blood samples within minutes. 相似文献
96.
Size-dependent trajectories of DNA macromolecules due to insulative dielectrophoresis in submicrometer-deep fluidic channels 总被引:1,自引:0,他引:1
Gea O. F. Parikesit Anton P. Markesteijn Oana M. Piciu Andre Bossche Jerry Westerweel Ian T. Young Yuval Garini 《Biomicrofluidics》2008,2(2)
In this paper, we demonstrate for the first time that insulative dielectrophoresis can induce size-dependent trajectories of DNA macromolecules. We experimentally use λ (48.5 kbp) and T4GT7 (165.6 kbp) DNA molecules flowing continuously around a sharp corner inside fluidic channels with a depth of 0.4 μm. Numerical simulation of the electrokinetic force distribution inside the channels is in qualitative agreement with our experimentally observed trajectories. We discuss a possible physical mechanism for the DNA polarization and dielectrophoresis inside confining channels, based on the observed dielectrophoresis responses due to different DNA sizes and various electric fields applied between the inlet and the outlet. The proposed physical mechanism indicates that further extensive investigations, both theoretically and experimentally, would be very useful to better elucidate the forces involved at DNA dielectrophoresis. When applied for size-based sorting of DNA molecules, our sorting method offers two major advantages compared to earlier attempts with insulative dielectrophoresis: Its continuous operation allows for high-throughput analysis, and it only requires electric field strengths as low as ∼10 V∕cm. 相似文献
97.
Benedicta D’Souza Vivian D’Souza S. Sowmya G. Seema C. N. Hemalatha M. Anu G. Sajana 《Indian journal of clinical biochemistry : IJCB》2008,23(3):218-222
The study was conducted to find out the extent of lipid peroxidation and antioxidant status in ischemic stroke patients (ISPs)
with and without diabetes. Malondialdehyde (MDA) was studied as a marker of lipid peroxidation. Glutathione (GSH), uric acid
and ceruloplasmin were estimated to study the antioxidant potential of ISPs. Significantly higher levels of MDA were found
in both the groups of ISPs and the increase in MDA was more in ISPs without diabetes. GSH levels were decreased significantly
in both the groups of ISPs and maximum decline was found in ISPs with diabetes. Uric acid levels were significantly increased
in both the groups of ISPs. Ceruloplasmin levels were increased significantly in ISPs without diabetes, whereas its levels
were slightly decreased in ISPs with diabetes. A negative correlation was found between MDA and the antioxidants GSH, uric
acid and ceruloplasmin in ISPs with diabetes. This study suggests that there is an association between ischemic stroke and
increased oxidative stress and the antioxidant potential is impaired in both the groups of ISPs with and without diabetes. 相似文献
98.
Joe D. Nichols 《Learning Environments Research》2006,9(2):149-161
This project focused on the goal of establishing a classroom model of motivation in which the source of student motivation is based on internal mechanisms or structures, along with the establishment of greater self-regulatory opportunities for students, and which results in greater student empowerment and motivation. One-hundred current elementary and secondary teachers and 100 university preservice teacher education students completed a 40-item Likert-type questionnaire that focused on four classroom dimensions of affirmation, rejection, student empowerment and teacher control. The results of this project suggested that, although veteran and preservice teachers agreed on the need for teacher control in the classroom, there was less agreement about their perceptions of the need to create a classroom environment of positive affirmation and student empowerment. Implications for future research and the need for creating an affirming, empowering, motivational classroom environment are discussed in light of the limitations for teachers and schools to encourage these constructs associated with recent federal legislative policies. 相似文献
99.
Richard O. Welsh 《Journal of Education for Students Placed at Risk》2018,23(1-2):70-92
ABSTRACTMobile students and absent students are important subsets of at-risk students in schools and districts nationwide. As such, student mobility and school absenteeism are two challenges in K-12 education with significant policy and equity implications. Although both issues are at the nexus of schooling and society and there is an apparent overlap in the attributes of these student subgroups, school absenteeism and student mobility are often discussed in separate conversations. This article connects the two disparate literatures in hopes of forging stronger ties that may benefit policymakers, researchers, educators, and students. The limited empirical evidence is mixed but suggests that school absenteeism and student mobility are correlated and absenteeism plays a small mediating role in the relationship between student mobility and student outcomes. The reasons underlying student mobility and student absenteeism are interrelated but not all reasons are common. The overlapping causes of student mobility and chronic absenteeism indicate that economic and social circumstances are important underlying factors. In particular, poverty is a key shared reason for missing or switching schools. Although both phenomena contribute to disparities in educational opportunities, experiences, and outcomes, this study posits that changing schools and missing school provide instructive examples of how inequality in society may be reproduced in districts and schools. Recommendations to address both phenomena and directions for future research are discussed. 相似文献
100.
John O’Neill 《教育政策杂志》2013,28(1):17-31
This paper examines recent privatisation practices in New Zealand public schooling. The standard political rhetoric is that free publicly provided schooling is guaranteed by statute. This position may be challenged by reference to two apparently insignificant practical examples of the way in which policy gives effect to privatisation in public schooling: (1) the commissioning of national assessment strategy policy advice, and (2) the award of contestable funding for the provision of support services to schools. It is argued that such practices advance neoliberal theories of schooling at the expense of the previous social democratic liberal settlement. The paper considers some possible consequences of increased privatisation of policy advice and service provision for understandings of and commitments to public schooling. 相似文献