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321.
322.
Ability to perform cytogenetic interrogations on circulating tumor cells (CTCs) from the blood of cancer patients is vital for progressing toward targeted, individualized treatments. CTCs are rare compared to normal (bystander) blood cells, found in ratios as low as 1:109. The most successful isolation techniques have been immunocytochemical technologies that label CTCs for separation based on unique surface antigens that distinguish them from normal bystander cells. The method discussed here utilizes biotin-tagged antibodies that bind selectively to CTCs. The antibodies are introduced into a suspension of blood cells intending that only CTCs will display surface biotin molecules. Next, the cell suspension is passed through a microfluidic channel that contains about 9000 transverse, streptavidin coated posts. A CTC making contact with a post has the opportunity to engage in a biotin-streptavidin reaction that immobilizes the cell. Bystander blood cells remain in suspension and pass through the channel. The goal of the present study is to establish the technical performance of these channels as a function of antigen density and operating conditions, especially flow rate. At 18 μL/min, over 70% of cells are captured at antigen densities greater than 30 000 sites/cell while 50% of cells are captured at antigen densities greater than 10 000. It is found that lower flow rates lead to decreasing cell capture probabilities, indicating that some streamlines develop which are never close enough to a post to allow cell-post contact. Future modeling and streamline studies using computational fluid dynamics software could aid in optimization of channel performance for capture of rare cells.  相似文献   
323.

Collaboration as a cornerstone of effective school inclusion is an idea that has high theoretical currency among many scholars in the areas of special education and educational leadership. The challenge for educational practitioners is to find ways to implement high-quality special education programs collaboratively amid the public call for school efficiency and accountability. Accordingly, the primary purpose of the qualitative research project reported in this article was to examine inherent challenges in the implementation of school inclusion programs in ten public schools in North Louisiana over a three-year period. Data collection methods included participatory observation, semi-structured interviews with nine teachers and three principals in four schools, two focus groups, and a document search. The findings revealed the critical and challenging role of the principal for establishing collaborative cultures for successful school inclusion. Additionally, special education teachers and general education teachers experienced intrapersonal and interpersonal value conflicts in the pursuit of educational equity amidst a climate of school accountability.  相似文献   
324.
Using US national data, this study examines the levels and interactions between reputational rankings, average publications, citations, and external research support across 30 disciplines. The analyses show great variation among the disciplines in average and range of publications, citations, and external research support. They also show that the intercorrelations among the measures vary greatly by discipline. For example, the correlation between average publication level and reputational rankings was substantial in chemistry (.87), but weak in industrial engineering (.20); the correlation between the level of research support and reputation was strong in psychology (.74), but very small in astronomy (.14). Comparison of departments ranked in the top 10 with those ranked near the bottom showed that it was possible for departments to rank very high in a discipline but have publication, citation, and support levels below departments ranked near the bottom. The implications for quality and increasing status in higher education are discussed.  相似文献   
325.
Leaders within education must weigh a number of fundamentals as they engage the needs of the stakeholders they represent within the political, social and economic context they operate within. Leaders must consider the unique needs and capabilities of individuals who might not possess similar abilities or talents to those of the majority. In this paper, we explore the capability approach as a frame to consider such contextual fundamentals in inclusive education leadership. In order to examine how educational leaders address the diverse needs of the groups they serve, we interviewed five central office educational administrators in the USA with the responsibility for leading programming for students with special needs. Using a human capabilities frame, we developed targeted questions to determine whether school leaders uphold the tenets of this theoretical foundation within their district's practices in an era of tight fiscal management and accountability. Findings indicate that those leaders whose districts had the highest level of inclusion for most students, including students with significant disabilities, most closely align with the capability approach. Recommendations for continued research and implications for both practice and policy are included.  相似文献   
326.
The purpose of this study was to explore how often 159 practicing teachers enrolled in a university Master's degree principal preparation program observed their mentor principals model the four mandated Texas standards‐based instructional leadership competencies for the principalship. The competencies focus on leadership through curriculum and planning, nurturing and sustaining the instructional program, implementing a staff evaluation plan and applying decision‐making skills. Findings on the four competencies ranged from a high of 59.1% to a low of only 44.7% of the participants who indicated that they observed their mentor principals modeling these four competencies at least ‘usually.’  相似文献   
327.
Introduction

Historically, two periods are discernible in the development of the system of extra-curricular activities in the Israeli schools — the first period, from the founding of the first Israeli high school around the beginning of the twentieth century to the establishment of the State of Israel (1948), and the second period, from 1948 to the present. The main difference between the two stages lies in the degree of local autonomy in the administration of the activity program.  相似文献   
328.
ABSTRACT

To improve students' functional understanding of plagiarism, a variety of approaches was tried within a comprehensive information literacy program. Sessions were taught as a “module” inside a required communications skills class at a private university. Approaches taken included control, direct-instruction, and student-centered sessions. Students were taught content and definitions regarding plagiarism, what circumstances or instances constitute plagiarism, where to go for help in avoiding plagiarism, and what constitutes appropriate paraphrasing. Pretest and posttest scores indicated that no approach performed significantly better than the others; however, even though students improved across all methods, they nonetheless showed the need for more hands-on practice.  相似文献   
329.

This experiment suggests that recognition and recall are better for radio commercials with imagery‐eliciting copy than for commercials without imagery‐eliciting copy.  相似文献   
330.
Popular Music     
Frank Tirro Jazz: A History (New York: Norton, 1977—$16.95 in trade edition; $12.95 in text edition, both hardback)

Leonard Feather Inside Jazz (New York: Da Capo, 1977—$4.95, paper)

Jim Haskins The Cotton Club (New York: Random House, 1977—$15.00, with paperback edition available)

Jeff Todd Titon Early Downhome Blues: A Musical and Cultural Analysis (Urbana: University of Illinois Press, 1977—$16.50)  相似文献   
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