6,372 research outputs found

    An Automated System for Chromosome Analysis

    Get PDF
    The design, construction, and testing of a complete system to produce karyotypes and chromosome measurement data from human blood samples, and to provide a basis for statistical analysis of quantitative chromosome measurement data are described

    Advisor and Student Experiences of Summer Support for College-intending, Low-income high school graduates

    Get PDF
    Summer melt occurs when students who have been accepted to college and intend to enroll fail to matriculate in college in the fall semester after high school. A high rate of summer melt contributes to the lower postsecondary attainment rates of low-income students, in particular. This article presents qualitative findings from two interventions intended to reduce summer melt among low-income, urban high school graduates who had been accepted to college and indicated their intention to enroll. Results from student and counselor surveys, interviews, and focus groups point to a web of personal and contextual factors that collectively influence students' college preparation behaviors and provide insight into the areas of summer supports from which students like these can benefit. The data fit an ecological perspective, in which personal, institutional, societal, and temporal factors interact to affect students' behaviors and outcomes. A model of summer intervention shows that obstacles in completing college financing and informational tasks can lead college-intending students to re-open the question of where or whether to attend college in the fall after high school graduation. Given the pressure of concerns about how to actualize their offer of admission, students rarely engage in the anticipatory socialization activities that might help them make optimal transitions into college

    Structural and dynamical characteristics of mesoscopic H+^+[H2_2O]n_n clusters

    Get PDF
    Structural and dynamical characteristics pertaining to the solvation of an excess proton in liquid-like nanoclusters of the type [H2_2O]n_n are investigated using Molecular Dynamics experiments. Three different aggregate sizes were analyzed: n=10,n=10, 21 and 125. The simulation experiments were performed using a multistate empirical valence bond Hamiltonian model. While in the smallest aggregates the proton occupies a central position, the stable solvation environments for n=21n=21 and 125 are located at the cluster boundaries. In all cases, the structure of the closest solvation shell of the excess charge remains practically unchanged and coincides with that observed in bulk water. Compared to results obtained in bulk, the computed rates for proton transfer in clusters are between one and two orders of magnitude slower, and tend to increase for larger cluster sizes.Comment: 16 pages, 6 figures, to be published in Journal of Molecular Liquids, EMLG2006 special issu

    More than Dollars for Scholars: The Impact of the Dell Scholars Program on College Access, Persistence and Degree Attainment

    Get PDF
    Although college enrollment rates have increased substantially over the last several decades, socioeconomic inequalities in college completion have actually widened over time. A critical question, therefore, is how to support low-income and first-generation students to succeed in college after they matriculate. We investigate the impact of the Dell Scholars Program which provides a combination of generous financial support and individualized advising to scholarship recipients before and throughout their postsecondary enrollment. The program's design is motivated by a theory of action that, in order to meaningfully increase the share of lower-income students who earn a college degree, it is necessary both to address financial constraints students face and to provide ongoing support for the academic, cultural and other challenges that students experience during their college careers. We isolate the unique impact of the program on college completion by capitalizing on an arbitrary cutoff in the program's algorithmic selection process. Using a regression discontinuity design, we find that although being named a Dell Scholar has no impact on initial college enrollment or early college persistence, scholars at the margin of eligibility are significantly more likely to earn a bachelor's degree on-time or six years after high school graduation. These impacts are sizeable and represent a nearly 25 percent or greater increase in both four- and six-year bachelor's attainment. The program is resource intensive. Yet, back-of-theenvelope calculations indicate that the Dell Scholars Program has a positive rate of return

    An automated system for chromosome analysis. Volume 1: Goals, system design, and performance

    Get PDF
    The design, construction, and testing of a complete system to produce karyotypes and chromosome measurement data from human blood samples, and a basis for statistical analysis of quantitative chromosome measurement data is described. The prototype was assembled, tested, and evaluated on clinical material and thoroughly documented

    Automated quantitative muscle biopsy analysis system

    Get PDF
    An automated system to aid the diagnosis of neuromuscular diseases by producing fiber size histograms utilizing histochemically stained muscle biopsy tissue. Televised images of the microscopic fibers are processed electronically by a multi-microprocessor computer, which isolates, measures, and classifies the fibers and displays the fiber size distribution. The architecture of the multi-microprocessor computer, which is iterated to any required degree of complexity, features a series of individual microprocessors P.sub.n each receiving data from a shared memory M.sub.n-1 and outputing processed data to a separate shared memory M.sub.n+1 under control of a program stored in dedicated memory M.sub.n

    National governments doing business on-line : an Australian look at current practice and future hazards

    Get PDF
    Governments around the world are taking advantage of the numerous benefits offered by the World Wide Web in order to provide client services to citizens. Australia has been a leader in this trend. The literature in this area focuses primarily on the pragmatic issues such as governmental accountability and transparency, interactivity, policy making, security and privacy, quality and costs. Along with the positive accounts of eGovernment development, however, some concerns are emerging in the literature. This paper examines such issues with particular reference to national governments. Although Australia can be proud of its position as a leader in bringing government business to the Web, it must also be cognisant of the concerns about eGovernment that are being more widely identified.<br /
    corecore