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245 results on '"Hawkes, Robert"'

229. Development of an Advanced Dust Telescope

Author

Srama, R., Srowig, A., Rachev, M., Grün, E., Kempf, S., Moragas-Klostermeyer, G., Conlon, T., Harris, D., Auer, S., Glasmachers, A., Helfert, S., Linnemann, H., Tschernjawski, V., Hawkes, Robert, editor, Mann, Ingrid, editor, and Brown, Peter, editor

Published
2005
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243. Comparison of first pass bolus AIFs extracted from sequential 18F-FDG PET and DSC-MRI of mice.

Author

Evans, Eleanor, Sawiak, Stephen J., Ward, Alexander O., Buonincontri, Guido, Hawkes, Robert C., and Adrian Carpenter, T.

Subjects
*BOLUS drug administration, *ARTERIAL physiology, *POSITRON emission tomography, *MAGNETIC resonance imaging, *LABORATORY mice, *BLOOD sampling
Abstract

Abstract: Accurate kinetic modelling of in vivo physiological function using positron emission tomography (PET) requires determination of the tracer time–activity curve in plasma, known as the arterial input function (AIF). The AIF is usually determined by invasive blood sampling methods, which are prohibitive in murine studies due to low total blood volumes. Extracting AIFs from PET images is also challenging due to large partial volume effects (PVE). We hypothesise that in combined PET with magnetic resonance imaging (PET/MR), a co-injected bolus of MR contrast agent and PET ligand can be tracked using fast MR acquisitions. This protocol would allow extraction of a MR AIF from MR contrast agent concentration–time curves, at higher spatial and temporal resolution than an image-derived PET AIF. A conversion factor could then be applied to the MR AIF for use in PET kinetic analysis. This work has compared AIFs obtained from sequential DSC-MRI and PET with separate injections of gadolinium contrast agent and 18F-FDG respectively to ascertain the technique′s validity. An automated voxel selection algorithm was employed to improve MR AIF reproducibility. We found that MR and PET AIFs displayed similar character in the first pass, confirmed by gamma variate fits (p<0.02). MR AIFs displayed reduced PVE compared to PET AIFs, indicating their potential use in PET/MR studies. [Copyright &y& Elsevier]

Published
2014
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244. The Whole World Was Their Classroom: The Contributions of Harry and Bonaro Overstreet to the Field of Adult Education

Author

Rappaport, Yvonne K. M.S., Adult and Continuing Education, Stubblefield, Harold W., Wiswell, Albert K., Bell, Norris, Hawkes, Robert T. Jr., and Boucouvalas, Marcie

Subjects
civic education, adult education, mental health
Abstract

This dissertation was a historical study of the lives and contributions to the field of adult education of Harry Allen Overstreet (1875-1970) and Bonaro Wilkinson Overstreet (1903-1985) who taught and wrote both individually and as a team. Their adult education efforts as lecturers and authors spanned more than forty years and reached millions of adults. The Overstreets carved out a special niche for themselves as educators who believed it was essential to reach the general public with knowledge that would enable them to lead more productive and fulfilling lives. They believed that adult education held out great promise that mature citizens could effectively improve their minds and could significantly improve social conditions. The Overstreets were fervent believers in democratic traditions and values and they strongly emphasized the need for citizens to step up to their responsibilities with regard to civil rights and community development. The Overstreets' definition of adult education was inclusive rather than exclusive, thus they sought to utilize the findings of the various psychological and social sciences to help citizens in the search for creative fulfillment in human relations. They took it as their task to integrate and clarify the findings of many disciplines for the education of the masses. Their books were widely read and their lectures appealed to a wide audience including businessmen, laborers, parents, minority groups, mental health groups, students and teachers. Harry Overstreet brought to the field of adult education the trained mind of a professional philosopher who enjoyed a civilized argument and spirited discussion. Bonaro brought a poetic sensitivity that could find a meaningful metaphor for most situations. They were also innovators. Harry Overstreet, an adult educator, developed the panel method of discussion that is widely used throughout the world as a means of presenting ideas in action to an audience. He and Bonaro developed a two person give and take lecture method which was called the Overstreet Colloquy and they developed a method of community problem solving through carefully structured workshops. A number of their collaborative publication efforts required extensive research. Their adult education books included Town Meeting Comes to Town, Leaders For Adult Education, and Where Children Come First which was a study of the PTA movement. The greatest commercial success was The Mature Mind in which sales were unprecedented for a book that was essentially about adult education. Aside from its popular appeal it was a solid scholarly achievement which was based on the insights and findings of Pavlov, Freud, Binet and Thorndike. The Overstreets expanded the concept of adult education to include the mental health movement and they succeeded in making a number of contributions to that endeavor. As part of their civic education responsibility the Overstreets researched and wrote a number of books on communism and totalitarian extremism as exemplified by Senator McCarthy and the far right. They achieved some fame in this area when President Eisenhower was photographed reading one of their books. The Overstreets lived full lives to the very end and were a kind of living advertisement for adult education. Norman Cousins, who was an admirer and disciple of both, wrote that as a team they "functioned synergistically." This was an apt description of two dedicated people who thoroughly enjoyed learning and teaching and writing together every day. Ed. D.

Published
1998

245. Comparison of first pass bolus AIFs extracted from sequential 18 F-FDG PET and DSC-MRI of mice.

Author

Evans E, Sawiak SJ, Ward AO, Buonincontri G, Hawkes RC, and Carpenter TA

Abstract

Accurate kinetic modelling of in vivo physiological function using positron emission tomography (PET) requires determination of the tracer time-activity curve in plasma, known as the arterial input function (AIF). The AIF is usually determined by invasive blood sampling methods, which are prohibitive in murine studies due to low total blood volumes. Extracting AIFs from PET images is also challenging due to large partial volume effects (PVE). We hypothesise that in combined PET with magnetic resonance imaging (PET/MR), a co-injected bolus of MR contrast agent and PET ligand can be tracked using fast MR acquisitions. This protocol would allow extraction of a MR AIF from MR contrast agent concentration-time curves, at higher spatial and temporal resolution than an image-derived PET AIF. A conversion factor could then be applied to the MR AIF for use in PET kinetic analysis. This work has compared AIFs obtained from sequential DSC-MRI and PET with separate injections of gadolinium contrast agent and 18 F-FDG respectively to ascertain the technique's validity. An automated voxel selection algorithm was employed to improve MR AIF reproducibility. We found that MR and PET AIFs displayed similar character in the first pass, confirmed by gamma variate fits (p<0.02). MR AIFs displayed reduced PVE compared to PET AIFs, indicating their potential use in PET/MR studies.

Published
2014
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