4,644 research outputs found

    America’s College Promise: An Economic Evaluation of President Obama’s Free Community College Plan

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    In his 2015 State of the Union Address, President Obama announced “America’s College Promise,” a plan to make community college free for all American families making less than $200,000. In this thesis, I provide an analysis of the plan and provide an evaluation of its potential impact on the education attainment gap in the United States. I also evaluate the plan’s various components and assess its potential impact on community college student enrollment, completion, and transfer to four-year universities. Lastly, I offer recommendations for improvement

    Visualisation of J-type counter-current chromatography: A route to understand hydrodynamic phase distribution and retention

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    This article can be accessed from the link below - Copyright @ 2012 Elsevier. The article was made available through open access by the Brunel Open Access Publishing Fund.This paper has addressed decade sought-after questions on phase bilateral distribution and stationary phase retention in any J-type high-speed counter-current chromatographic (CCC) centrifuge. Using a 2-D spiral column operated on such a CCC device and an aqueous two-phase system, this work systematically observed the phase interaction during transitional period and at dynamic equilibration under stroboscopic illumination. The experimental results thus obtained were used to examine the effects of the liquid–solid friction force, tangential centrifugal force, and physical properties of the two-phase system on hydrodynamic phase behaviour. We identified that (a) density difference between lower and upper phases is the critical factor to cause unusual phase bilateral distribution in the 2-D spiral column and (b) interfacial tension (manifested primarily as phase settling time) of any two-phase system is the critical factor in explaining inability to retain stationary phase in 3-D helical column and, for certain flow modes, in the 2-D spiral column. This work thus has extended or modified the well-established rule-of-thumb for operating J-type CCC devices and our conclusions can accommodate virtually all the anomalies concerning both hydrophobic and hydrophilic phase systems. To this end, this work has not only documented valuable experimental evidences for directly observing phase behaviour in a CCC column, but also finally resolved fundamentally vital issues on bilateral phase distribution orientation and stationary phase retention in 2-D spiral and 3-D helical CCC columns. Revised recommendations to end users of this technology could thus be derived out of the essence of the present work presumably following further experimental validation and a consensus in the CCC R&D and manufacturing circle.This work is funded by the BBSRC (UK) grant BB/C5063341/1, by MoST (China) as a Major State Basic Research Development Programme grant 2007CB714303 (973 Programme), by M & G Trading, and by Shanghai Science and Technology Board grant 11DZ2292700

    Spatially distributed force measurement for small terrestrial animals

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    The 11th International Symposium on Adaptive Motion of Animals and Machines. Kobe University, Japan. 2023-06-06/09. Adaptive Motion of Animals and Machines Organizing Committee.Poster Session P7
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