258 results on '"J. A. Magee"'
Search Results
2. Persistent Cancer-Related Fatigue After Breast Cancer Treatment Predicts Postural Sway and Postexertional Changes in Sit-to-Stand Strategy
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Stephen Wechsler, Janet Kneiss, Benjamin Adams, and Lisa J. Wood Magee
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Oncology ,Oncology (nursing) ,Rehabilitation ,Physical Therapy, Sports Therapy and Rehabilitation - Abstract
Chemotherapy-induced peripheral neuropathy (CIPN) is considered a primary mechanism of imbalance among women diagnosed with breast cancer. Recent evidence, however, suggests that cancer-related fatigue (CRF) may also influence balance.Examine the contributions of CRF and CIPN to static and dynamic balance before and after a period of fatiguing exercise.This is a secondary analysis of data examining functional differences between women with breast cancer with and without persistent CRF. Postural sway was measured during static standing and the rising phase of an instrumented sit-to-stand (ISTS) before and after exercise. Regression analyses were performed to determine how CRF and severity of CIPN predicted sway and how much variance was attributable to each.Greater CRF predicted increased pre-,This analysis is limited by its small and demographically homogenous sample.These results suggest that CRF may influence balance independent of CIPN symptoms. While CIPN remains a risk factor for imbalance in this population, CRF warrants consideration in clinical practice and research as a mechanism of postural instability.
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- 2022
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3. Increased Fatigability in Women With Persistent Cancer-Related Fatigue After Breast Cancer Treatment: A Pilot Study
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Lisa J. Wood Magee, Janet Kneiss, Stephen Wechsler, Ayesha Bani Singh, Annie B. Fox, Jeffrey Peppercorn, and William F. Pirl
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Oncology ,Oncology (nursing) ,Rehabilitation ,Physical Therapy, Sports Therapy and Rehabilitation - Published
- 2022
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4. The Role of Exercise Self-Efficacy in Exercise Participation Among Women With Persistent Fatigue After Breast Cancer: A Mixed-Methods Study
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Stephen Wechsler, Mei R Fu, Kathleen Lyons, Kelley C Wood, and Lisa J Wood Magee
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Physical Therapy, Sports Therapy and Rehabilitation - Abstract
Objective Survivors of breast cancer with persistent cancer-related fatigue (CRF) report less exercise participation compared with survivors of breast cancer without CRF. Although CRF predicts other domains of self-efficacy among survivors, the effect of CRF on exercise self-efficacy (ESE)—an important predictor of exercise participation—has not been quantified. This study examined the relationship between CRF, ESE, and exercise participation and explored the lived experience of engaging in exercise among survivors of breast cancer with persistent CRF. Methods Fifty-eight survivors of breast cancer (3.7 [SD = 2.4] years after primary treatment) self-reported CRF, ESE, and exercise participation (hours of moderate-intensity exercise per week). Regression and mediation analyses were conducted. Survivors who reported clinically significant CRF and weekly exercise were purposively sampled for 1-on-1 interviews (N = 11). Thematic analysis was performed across participants and within higher versus lower ESE subsets. Results Greater CRF predicted lower ESE (β = −0.32) and less exercise participation (β = −0.08). ESE mediated the relationship between CRF and exercise participation (β = −0.05, 95% CI = −0.09 to −0.02). Qualitative data showed that survivors of breast cancer with higher ESE perceived exercise as a strategy to manage fatigue, described self-motivation and commitment to exercise, and had multiple sources of support. In contrast, survivors with lower ESE described less initiative to manage fatigue through exercise, greater difficulty staying committed to exercise, and less support. Conclusions Survivors of breast cancer with persistent CRF may experience decreased ESE, which negatively influences exercise participation. Clinicians should screen for or discuss confidence as it relates to exercise and consider tailoring standardized exercise recommendations for this population to optimize ESE. This may facilitate more sustainable exercise participation and improve outcomes. Impact This study highlights the behavioral underpinnings of CRF as a barrier to exercise. Individualized exercise tailored to optimize ESE may facilitate sustainable exercise participation among survivors of breast cancer with CRF. Strategies for clinicians to address ESE are described and future research is suggested. Lay Summary Women with fatigue after breast cancer treatment may have lower confidence about their ability to engage in exercise. Individually tailoring exercise to build confidence as it relates to exercise may result in more consistent exercise and better health-related outcomes.
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- 2022
5. Deep Exclusive Electroproduction of π0 at High Q2 in the Quark Valence Regime
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N. H. Saylor, D. Bulumulla, Wouter Deconinck, E. Pooser, L. Ye, B. Crowe, Weidong Li, B. P. Quinn, Y. Huang, Douglas Higinbotham, E. Fuchey, C. Ayerbe Gayoso, Y. Zhao, S. A. Wood, M. K. Jones, Darko Androić, Jie Liu, A. J. Sarty, Z. Ye, K. Hamilton, E. McClellan, M. E. Christy, A. Liyanage, J. Bane, F. Georges, O. F. Obretch, C. Gal, S. F. Ali, Bogdan Wojtsekhowski, P. M. King, C. Palatchi, F. Hauenstein, J. Roche, T. Averett, P. E. Reimer, J. P. Chen, G. M. Urciuoli, Franco Meddi, M. H. Shabestari, C. Fanelli, K. A. Aniol, R. I. Pomatsalyuk, B. Aljawrneh, Shams Rahman, C. E. Hyde, R. Beminiwattha, X. Yan, Andrew Puckett, E. Voutier, E. Cisbani, S. J. Nazeer, Chunhui Chen, C. Desnault, M. Carmignotto, O. Glamazdin, J. Castellano, Z. Ahmed, L. Ou, F. De Persio, Olfred Hansen, S. Allison, J. R. M. Annand, Simon Širca, T. Gautam, D. Nguyen, B. Sawatzky, G. M. Huber, S. Danagoulian, J. C. Cornejo, Tanja Horn, C. M. Jen, F. Tortorici, T. Su, S. Alsalmi, Yicheng Wang, G. Hamad, B. Duran, Kalyan Allada, Maxime Defurne, R. Michaels, Hongjun Liu, D. Gaskell, Juliette Mammei, David Hamilton, Pete Markowitz, L. A. Thorne, E. J. Brash, V. M. Gray, C. Munoz Camacho, D. Adikaram, T. W. Danley, Y. Tian, K. Park, Ping Zhu, L. S. Myers, M. N. H. Rashad, Rolf Ent, R. A. Montgomery, D. Biswas, S. Malace, W. Henry, A. Sun, M. Dlamini, H. Atac, N. Israel, R. Trotta, X. Bai, V. Bellini, N. Ton, R. Spies, Alexandre Camsonne, A. Stefanko, C. Gu, K. Bartlett, K. Jin, B. A. Clary, Kondo Gnanvo, M. Nycz, T. Holmstrom, P.-J. Lin, Shanfeng Li, C. Yero, T. Hague, Taya Chetry, Jie Zhang, J. Bericic, J. Campbell, A. Mkrtchyan, Nikos Sparveris, K. Mesik, I. Sapkota, Vladimir Nelyubin, A. Shahinyan, N. Compton, D. Di, Eliahu Cohen, S. Sooriyaarachchilage, Cynthia Keppel, H. S. Ko, A. Kabir, V. A. Punjabi, D. G. Meekins, S. Barcus, V. Khachatryan, G. B. Franklin, P. Nadel-Turonski, N. Nuruzzaman, Chao Peng, G. R. Smith, H. F. Ibrahim, B. Karki, M. Duer, H. Albataineh, A. Subedi, S. Park, B. Schmookler, B. Pandey, Vincent Sulkosky, J. A. Magee, B. Waidyawansa, and S. Covrig Dusa
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Quark ,Physics ,Particle physics ,010308 nuclear & particles physics ,Momentum transfer ,General Physics and Astronomy ,Sigma ,Virtual particle ,Parton ,01 natural sciences ,Helicity ,Pion ,0103 physical sciences ,High Energy Physics::Experiment ,Nuclear Experiment ,010306 general physics ,Nucleon - Abstract
We report measurements of the exclusive neutral pion electroproduction cross section off protons at large values of $x_B$ (0.36, 0.48 and 0.60) and $Q^2$ (3.1 to 8.4 GeV$^2$) obtained from Jefferson Lab Hall A experiment E12-06-014. The corresponding structure functions $d\sigma_L/dt+\epsilon d\sigma_T/dt$, $d\sigma_{TT}/dt$, $d\sigma_{LT}/dt$ and $d\sigma_{LT'}/dt$ are extracted as a function of the proton momentum transfer $t-t_{min}$. The results suggest the amplitude for transversely polarized virtual photons continues to dominate the cross-section throughout this kinematic range. The data are well described by calculations based on transversity Generalized Parton Distributions coupled to a helicity flip Distribution Amplitude of the pion, thus providing a unique way to probe the structure of the nucleon.
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- 2021
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6. Detecting human impacts on the flora, fauna, and summer monsoon of Pleistocene Australia
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G. H. Miller, J. W. Magee, M. L. Fogel, and M. K. Gagan
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Environmental pollution ,TD172-193.5 ,Environmental protection ,TD169-171.8 ,Environmental sciences ,GE1-350 - Abstract
The moisture balance across northern and central Australia is dominated by changes in the strength of the Australian Summer Monsoon. Lake-level records that record changes in monsoon strength on orbital timescales are most consistent with a Northern Hemisphere insolation control on monsoon strength, a result consistent with recent modeling studies. A weak Holocene monsoon relative to monsoon strength 65–60 ka, despite stronger forcing, suggests a changed monsoon regime after 60 ka. Shortly after 60 ka humans colonized Australia and all of Australia's largest mammals became extinct. Between 60 and 40 ka Australian climate was similar to present and not changing rapidly. Consequently, attention has turned toward plausible human mechanisms for the extinction, with proponents for over-hunting, ecosystem change, and introduced disease. To differentiate between these options we utilize isotopic tracers of diet preserved in eggshells of two large, flightless birds to track the status of ecosystems before and after human colonization. More than 800 dated eggshells of the Australian emu (Dromaius novaehollandiae), an opportunistic, dominantly herbivorous feeder, provide a 140-kyr dietary reconstruction that reveals unprecedented reduction in the bird's food resources about 50 ka, coeval in three distant regions. These data suggest a tree/shrub savannah with occasionally rich grasslands was converted abruptly to the modern desert scrub. The diet of the heavier, extinct Genyornis newtoni, derived from >550 dated eggshells, was more restricted than in co-existing Dromaius, implying a more specialized feeding strategy. We suggest that generalist feeders, such as Dromaius, were able to adapt to a changed vegetation regime, whereas more specialized feeders, such as Genyornis, became extinct. We speculate that ecosystem collapse across arid and semi-arid zones was a consequence of systematic burning by early humans. We also suggest that altered climate feedbacks linked to changes in vegetation may have weakened the penetration of monsoon moisture into the continental interior, explaining the failure of the Holocene monsoon. Climate modeling suggests a vegetation shift may reduce monsoon rain in the interior by as much as 50%.
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- 2007
7. Measurement of the beam-normal single-spin asymmetry for elastic electron scattering from C12 and Al27
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R. W. Radloff, S. A. Page, John M. Finn, L. Lee, V. Tvaskis, L. Z. Ndukum, K. E. Mesick, S. Kowalski, Jongmin Lee, W. S. Duvall, A. Mkrtchyan, A. R. Lee, C. A. Davis, P. Solvignon, William A. Tobias, J. Leacock, Jay Benesch, J. A. Dunne, F. Guo, H. Mkrtchyan, M. M. Dalton, R. D. Carlini, B. Sawatzky, S. MacEwan, T. Seva, W. D. Ramsay, E. Korkmaz, D. G. Meekins, Kent Paschke, P. M. King, V. M. Gray, V. Tadevosyan, D. C. Jones, J. C. Cornejo, Jean-Francois Rajotte, J. Pan, M. H. Shabestari, P. Wang, J. A. Magee, R. S. Beminiwattha, Michael Gericke, R. Michaels, Fatiha Benmokhtar, Wouter Deconinck, B. Waidyawansa, D. S. Armstrong, Jonathan W. Martin, R. Subedi, S. Covrig Dusa, M. Kargiantoulakis, J. Leckey, Dipanwita Dutta, S. P. Wells, W. R. Falk, S. A. Wood, P. Zang, Darko Androić, D. T. Spayde, Vladimir Nelyubin, D. J. Mack, S. Zhamkochyan, M. E. Christy, A. Asaturyan, R. Silwal, J. F. Dowd, S. K. Phillips, T. A. Forest, J. Birchall, M. Elaasar, Geoffrey Smith, A. Subedi, R. Mahurin, M. J. McHugh, Riad Suleiman, Michael Pitt, Amrendra Narayan, D. Gaskell, V. Owen, C. Gal, W. T. H. van Oers, Nuruzzaman, J. R. Hoskins, Juliette Mammei, K. Bartlett, J. Roche, and Neven Simicevic
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Elastic scattering ,Physics ,Range (particle radiation) ,010308 nuclear & particles physics ,Scattering ,media_common.quotation_subject ,01 natural sciences ,Asymmetry ,Nuclear physics ,Momentum ,Transverse plane ,0103 physical sciences ,High Energy Physics::Experiment ,Nuclear Experiment ,010306 general physics ,Beam (structure) ,Spin-½ ,media_common - Abstract
We report measurements of the parity-conserving beam-normal single-spin elastic scattering asymmetries $B_n$ on $^{12}$C and $^{27}$Al, obtained with an electron beam polarized transverse to its momentum direction. These measurements add an additional kinematic point to a series of previous measurements of $B_n$ on $^{12}$C and provide a first measurement on $^{27}$Al. The experiment utilized the Qweak apparatus at Jefferson Lab with a beam energy of 1.158 GeV. The average lab scattering angle for both targets was 7.7 degrees, and the average $Q^2$ for both targets was 0.02437 GeV$^2$ (Q=0.1561 GeV). The asymmetries are $B_n$ = -10.68 $\pm$ 0.90 stat) $\pm$ 0.57 (syst) ppm for $^{12}$C and $B_n$ = -12.16 $\pm$ 0.58 (stat) $\pm$ 0.62 (syst) ppm for $^{27}$Al. The results are consistent with theoretical predictions, and are compared to existing data. When scaled by Z/A, the Q-dependence of all the far-forward angle (theta < 10 degrees) data from $^{1}$H to $^{27}$Al can be described by the same slope out to $Q \approx 0.35$ GeV. Larger-angle data from other experiments in the same Q range are consistent with a slope about twice as steep.
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- 2021
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8. Precision Measurement of the Beam-Normal Single-Spin Asymmetry in Forward-Angle Elastic Electron-Proton Scattering
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Wouter Deconinck, Riad Suleiman, M. H. Shabestari, L. Z. Ndukum, William A. Tobias, C. A. Davis, J. Leckey, J. A. Magee, S. Yang, Jongmin Lee, Amrendra Narayan, P. Solvignon, mrow, J. Roche, V. Tvaskis, M. M. Dalton, W. D. Ramsay, A. Mkrtchyan, S. MacEwan, D. Gaskell, M. Elaasar, Nuruzzaman, J. Beaufait, T. Seva, E. Korkmaz, V. M. Gray, A. R. Lee, B. Waidyawansa, D. T. Spayde, S. Covrig Dusa, Jean-Francois Rajotte, Roger Carlini, S. K. Phillips, mrow> weak, R. Subedi, M. K. Jones, Kent Paschke, K. Bartlett, S. A. Wood, P. Wang, Neven Simicevic, V. Owen, A. Asaturyan, W. R. Falk, J. Leacock, R. W. Radloff, R. Mahurin, P. Zang, Dipangkar Dutta, V. Tadevosyan, C. Gal, Fatiha Benmokhtar, J.C. Cornejo, K. E. Mesick, L. Lee, Vladimir Nelyubin, P. M. King, A. M. Micherdzinska, S. A. Page, F. Guo, H. Mkrtchyan, D. J. Mack, Darko Androić, R. S. Beminiwattha, mtext, A. Subedi, S. Zhamkochyan, W. T. H. van Oers, M. Kargiantoulakis, T. A. Forest, Michael Gericke, J. F. Dowd, Joseph Grames, S. Wells, J. M. Finn, K. Grimm, J. Pan, R. Silwal, J. A. Dunne, B. Sawatzky, D. C. Jones, R. Michaels, J. R. Hoskins, J. Birchall, Juliette Mammei, S. Kowalski, W. S. Duvall, J. W. Martin, J. Mei, N. Morgan, msub, R. T. Jones, Jay Benesch, Michael Pitt, D. G. Meekins, D. S. Armstrong, G. R. Smith, and M. J. McHugh
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Physics ,Scattering ,media_common.quotation_subject ,General Physics and Astronomy ,FOS: Physical sciences ,Observable ,Electron ,beam-normalization, single-spin asymmetry, scattering, transversaly polarized electrons, unpolarized nucleons ,01 natural sciences ,Asymmetry ,0103 physical sciences ,High Energy Physics::Experiment ,Atomic physics ,Nuclear Experiment (nucl-ex) ,010306 general physics ,Nucleon ,Nuclear Experiment ,Energy (signal processing) ,Beam (structure) ,Spin-½ ,media_common - Abstract
A beam-normal single-spin asymmetry generated in the scattering of transversely polarized electrons from unpolarized nucleons is an observable related to the imaginary part of the two-photon exchange process. We report a 2% precision measurement of the beam-normal single-spin asymmetry in elastic electron-proton scattering with a mean scattering angle of theta_lab = 7.9 degrees and a mean energy of 1.149 GeV. The asymmetry result is B_n = -5.194 +- 0.067 (stat) +- 0.082 (syst) ppm. This is the most precise measurement of this quantity available to date and therefore provides a stringent test of two-photon exchange models at far-forward scattering angles (theta_lab -> 0) where they should be most reliable., 6 pages, 3 figures; Slightly revised version, after referee's comments; accepted in PRL
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- 2020
9. Neutron Induced Fission Fragment Angular Distributions, Anisotropy, and Linear Momentum Transfer Measured with the NIFFTE Fission Time Projection Chamber
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Jonathan B. King, D. Higgins, T. R. Towell, Z. Q. Case, J. L. Klay, T. Classen, A. Kemnitz, C. L. Towell, D. L. Duke, L. Yao, E. Leal, E. Guardincerri, N. Fotiadis, M. Heffner, Samuele Sangiorgio, G. Oman, N. Walsh, L. Snyder, C. A. Hagmann, K. Kazkaz, M. P. Mendenhall, Christopher Prokop, V. Geppert-Kleinrath, K. J. Kiesling, Joseph Latta, T.S. Watson, Brett Manning, K. J. Brewster, Nathaniel Bowden, R. S. Towell, D. Hensle, M. Monterial, M. Lynch, J. A. Magee, B. Seilhan, J. T. Barker, J. S. Barrett, C. R. Hicks, Shea Mosby, W. Loveland, Walid Younes, Uwe Greife, J. Bundgaard, Robert Casperson, D. Cebra, Fredrik Tovesson, L. D. Isenhower, Kyle Schmitt, and J. Gearhart
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Physics ,Range (particle radiation) ,Time projection chamber ,010308 nuclear & particles physics ,Fission ,Nuclear Theory ,FOS: Physical sciences ,Observable ,Tracking (particle physics) ,01 natural sciences ,Nuclear physics ,Cross section (physics) ,0103 physical sciences ,Physics::Atomic and Molecular Clusters ,Neutron ,Nuclear Experiment (nucl-ex) ,010306 general physics ,Anisotropy ,Nuclear Experiment - Abstract
The Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) collaboration has performed measurements with a fission time projection chamber (fissionTPC) to study the fission process by reconstructing full three-dimensional tracks of fission fragments and other ionizing radiation. The amount of linear momentum imparted to the fissioning nucleus by the incident neutron can be inferred by measuring the opening angle between the fission fragments. Using this measured linear momentum, fission fragment angular distributions can be converted to the center-of-mass frame for anisotropy measurements. Angular anisotropy is an important experimental observable for understanding the quantum mechanical state of the fissioning nucleus and vital to determining detection efficiency for cross section measurements. Neutron linear momentum transfer to fissioning $^{235}$U, $^{238}$U, and $^{239}$Pu and fission fragment angular anisotropy of $^{235}$U and $^{238}$U as a function of neutron energies in the range 130 keV--250 MeV are presented.
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- 2020
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10. Measurement of material isotopics and atom number ratio with α-particle spectroscopy for a NIFFTE fission Time Projection Chamber actinide target
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J. A. Magee, C. A. Hagmann, Fredrik Tovesson, C. Prokop, B. Seilhan, W. Loveland, Denise Neudecker, A. Kemnitz, Daniel James Higgins, Mateusz Monterial, Nikolaos Fotiades, D. Cebra, D. Hensle, M. Heffner, L. Yao, L. D. Isenhower, N. Walsh, T.S. Watson, Samuele Sangiorgio, Kyle Schmitt, J. Gearhart, M. P. Mendenhall, R. S. Towell, Brett Manning, Jonathan B. King, Nathaniel Bowden, T. Classen, Uwe Greife, Shea Mosby, E. Leal-Cidoncha, J. L. Klay, J. Bundgaard, L. Snyder, Walid Younes, Robert Casperson, V. Geppert-Kleinrath, D.H. Dongwi, Kareem Kazkaz, Joseph Latta, and M. Anastasiou
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Physics ,Nuclear and High Energy Physics ,Time projection chamber ,Isotope ,Fission ,Analytical chemistry ,Atomic number ,Actinide ,Nuclear Experiment ,Mass spectrometry ,Spectroscopy ,Instrumentation ,Spectral line - Abstract
We present the results of a measurement of isotopic concentrations and atomic number ratio of a double-sided actinide target using α -spectroscopy and mass spectrometry. The double-sided actinide target, with predominantly 239Pu on one side and 235U on the other, was used in the fission Time Projection Chamber (fissionTPC) for a measurement of the neutron-induced fission cross-section ratio between the two isotopes. The measured atomic number ratio is needed to extract an absolute measurement fission cross-section ratio. The 239Pu/235U atom number ratio was measured with a combination of mass spectrometry and α -spectroscopy with a planar silicon detector achieving uncertainties of less than 1%. Different strategies for estimating isotopic concentration from the α -spectrum are presented to demonstrate the potential of these methods for non-destructive target assay. We found that a combination of fitting spectra with constraints from mass spectrometry, and summing counts in a region of the spectrum provided the most consistent results with the lowest uncertainty.
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- 2022
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11. A novel comparison of Møller and Compton electron-beam polarimeters
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Dipangkar Dutta, William A. Tobias, Amber McCreary, W.D. Ramsay, A. Mkrtchyan, B. S. Cavness, Douglas Storey, Kent Paschke, S. A. Page, C. Vidal, Amrendra Narayan, D. Gaskell, L. A. Dillon-Townes, D. C. Jones, P. Wang, Erik Urban, M. McDonald, J.C. Cornejo, J. R. Hoskins, R. S. Beminiwattha, Vladimir Nelyubin, A. Asaturyan, M. M. Dalton, Wouter Deconinck, S. Zhamkotchyan, E. Ihloff, P. Solvignon, G. Hays, R. T. Jones, P. M. King, S. Kowalski, J. W. Martin, V. Tvaskis, J. A. Magee, A. Micherdzinska, B. Waidyawansa, H. Mkrtchyan, L. Lee, Jay Benesch, Leonid Kurchaninov, G. D. Cates, Massachusetts Institute of Technology. Department of Physics, and Kowalski, Stanley B
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Nuclear and High Energy Physics ,Physics - Instrumentation and Detectors ,media_common.quotation_subject ,Polarimetry ,Electron ,Electron polarimetry ,01 natural sciences ,Asymmetry ,Møller polarimeter ,Optics ,Compton polarimeter ,0103 physical sciences ,High current ,010306 general physics ,Nuclear Experiment ,media_common ,Physics ,010308 nuclear & particles physics ,business.industry ,Astrophysics::Instrumentation and Methods for Astrophysics ,Compton scattering ,Polarimeter ,Polarization (waves) ,lcsh:QC1-999 ,Computational physics ,Cathode ray ,Physics::Accelerator Physics ,business ,lcsh:Physics ,Jefferson Lab - Abstract
We have performed a novel comparison between electron-beam polarimeters based on Møller and Compton scattering. A sequence of electron-beam polarization measurements were performed at low beam currents (< 5μA) during the Q[subscript weak] experiment in Hall-C at Jefferson Lab. These low current measurements were bracketed by the regular high current (180 μA) operation of the Compton polarimeter. All measurements were found to be consistent within experimental uncertainties of 1% or less, demonstrating that electron polarization does not depend significantly on the beam current. This result lends confidence to the common practice of applying Møller measurements made at low beam currents to physics experiments performed at higher beam currents. The agreement between two polarimetry techniques based on independent physical processes sets an important benchmark for future precision asymmetry measurements that require sub-1% precision in polarimetry. Keywords: Electron polarimetry, Compton polarimeter, Møller polarimeter, Jefferson Lab, United States. Department of Energy (Contract AC05-06OR23177), Natural Sciences and Engineering Research Council of Canada
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- 2017
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12. Fission fragment angular anisotropy in neutron-induced fission of U235 measured with a time projection chamber
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Nathaniel Bowden, Fredrik Tovesson, J. A. Magee, V. Geppert-Kleinrath, Jonathan B. King, D. Hensle, H. Leeb, J. L. Klay, L. Snyder, Uwe Greife, L. D. Isenhower, D. L. Duke, A. C. Tate, R. S. Towell, Kyle Schmitt, J. Gearhart, Samuele Sangiorgio, N. Walsh, C. A. Hagmann, M. P. Mendenhall, D. Higgins, W. Loveland, J. Ruz, Walid Younes, D. Cebra, E. Guardincerri, Brett Manning, T. Classen, M. Heffner, Robert Casperson, S. Watson, L. Yao, M. Cunningham, J. S. Barrett, J. Bundgaard, and B. Seilhan
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Physics ,Cluster decay ,Time projection chamber ,010308 nuclear & particles physics ,Fission ,Nuclear Theory ,Nuclear data ,Tracking (particle physics) ,01 natural sciences ,Nuclear physics ,Cross section (physics) ,0103 physical sciences ,Neutron ,Nuclear Experiment ,010306 general physics ,Anisotropy - Abstract
Fission fragment angular distributions can provide an important constraint on fission theory, improving predictive fission codes, and are a prerequisite for a precise ratio cross section measurement. Available anisotropy data is sparse, especially at neutron energies above 5 MeV. For the first time, a three-dimensional tracking detector is employed to study fragment emission angles and provide a direct measurement of angular anisotropy. The Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) collaboration has deployed the fission time projection chamber (fissionTPC) to measure nuclear data with unprecedented precision. The fission fragment anisotropy of $^{235}$U has been measured over a wide range of incident neutron energies from 180 keV to 200 MeV; a careful study of the systematic uncertainties complement the data.
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- 2019
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13. Precision Measurement of the Weak Charge of the Proton
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K. Bartlett, K. E. Mesick, W. R. Falk, P. M. King, R. S. Beminiwattha, A. Asaturyan, J. Leckey, P. Zang, J. Leacock, T. Averett, D. T. Spayde, M. M. Dalton, Ross D. Young, W. D. Ramsay, Vladimir Nelyubin, J. Balewski, J. F. Dowd, J. Roche, S. Yang, Darko Androić, A. Micherdzinska, M. Kargiantoulakis, John M. Finn, J. A. Magee, Kent Paschke, Jongmin Lee, R. W. L. Jones, P. Solvignon, S. Kowalski, L. Z. Ndukum, W. S. Duvall, S. Zhamkochyan, J. Birchall, V. Tvaskis, Riad Suleiman, A. R. Lee, B. Waidyawansa, J. Pan, D. C. Jones, Fatiha Benmokhtar, Wouter Deconinck, Jonathan W. Martin, S. Covrig Dusa, L. Lee, A. Mkrtchyan, Amrendra Narayan, R. Michaels, S. P. Wells, M. H. Shabestari, Geoffrey Smith, D. Gaskell, C. A. Davis, William A. Tobias, Jay Benesch, H. Mkrtchyan, Matthew Jones, Joseph Grames, S. A. Page, A. K. Opper, S. MacEwan, T. Seva, E. Korkmaz, Jean-Francois Rajotte, V. M. Gray, M. Poelker, C. Gal, D. S. Armstrong, J. A. Dunne, S. A. Wood, J. Mei, J. Beaufait, R. D. Carlini, Kathryn Grimm, F. Guo, S. K. Phillips, J. Diefenbach, P. Wang, D. J. Mack, N. Morgan, Michael Gericke, B. Sawatzky, T. A. Forest, R. Silwal, M. J. McHugh, M. Elaasar, R. Mahurin, J. C. Cornejo, Michael Pitt, R. Subedi, W. T. H. van Oers, Nuruzzaman, H. Nuhait, J. R. Hoskins, D. G. Meekins, Juliette Mammei, V. Tadevosyan, Dipangkar Dutta, Neven Simicevic, and A. Subedi
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Physics ,Particle physics ,Multidisciplinary ,Large Hadron Collider ,010308 nuclear & particles physics ,media_common.quotation_subject ,Electroweak interaction ,Dark matter ,FOS: Physical sciences ,Elementary particle ,Parity (physics) ,Weak interaction ,7. Clean energy ,01 natural sciences ,Asymmetry ,0103 physical sciences ,Higgs boson ,Nuclear Experiment (nucl-ex) ,010306 general physics ,weak charge of proton, parity violation, polarized electron beam ,Nuclear Experiment ,media_common - Abstract
The fields of particle and nuclear physics have undertaken extensive programs to search for evidence of physics beyond that explained by current theories. The observation of the Higgs boson at the Large Hadron Collider completed the set of particles predicted by the Standard Model (SM), currently the best description of fundamental particles and forces. However, the theory's limitations include a failure to predict fundamental parameters and the inability to account for dark matter/energy, gravity, and the matter-antimater asymmetry in the universe, among other phenomena. Given the lack of additional particles found so far through direct searches in the post-Higgs era, indirect searches utilizing precise measurements of well predicted SM observables allow highly targeted alternative tests for physics beyond the SM. Indirect searches have the potential to reach mass/energy scales beyond those directly accessible by today's high-energy accelerators. The value of the weak charge of the proton Q_W^p is an example of such an indirect search, as it sets the strength of the proton's interaction with particles via the well-predicted neutral electroweak force. Parity violation (invariance under spatial inversion (x,y,z) -> (-x,-y,-z)) is violated only in the weak interaction, thus providing a unique tool to isolate the weak interaction in order to measure the proton's weak charge. Here we report Q_W^p=0.0719+-0.0045, as extracted from our measured parity-violating (PV) polarized electron-proton scattering asymmetry, A_ep=-226.5+-9.3 ppb. Our value of Q_W^p is in excellent agreement with the SM, and sets multi-TeV-scale constraints on any semi-leptonic PV physics not described within the SM., Direct link to Nature Version "https://rdcu.be/954U"
- Published
- 2019
14. Augmented Reality Forward Damage Control Procedures for Nonsurgeons: A Feasibility Demonstration
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Shawn F. Kane, J. Harvey Magee, Geoffrey T Miller, William N Vasios, Robert F Buckman, Tyler E Harris, Stephen F DeLellis, Y. Sammy Choi, Kenneth J. Nelson, and Jerry S Heneghan
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Damage control ,Computer science ,Wearable computer ,Single test ,03 medical and health sciences ,0302 clinical medicine ,medicine.artery ,medicine ,Humans ,030212 general & internal medicine ,Simulation ,Surgical team ,Augmented Reality ,Public Health, Environmental and Occupational Health ,External iliac artery ,Mentoring ,030208 emergency & critical care medicine ,General Medicine ,United States ,Surgery, Computer-Assisted ,Damage control surgery ,Surgical Procedures, Operative ,Emergency evacuation ,Feasibility Studies ,Wounds and Injuries ,Augmented reality ,Education, Medical, Continuing - Abstract
IntroductionThis article presents an emerging capability to project damage control procedures far forward for situations where evacuation to a formal surgical team is delayed. Specifically, we demonstrate the plausibility of using a wearable augmented reality (AR) telestration device to guide a nonsurgeon through a damage control procedure.MethodsA stand-alone, low-profile, commercial-off-the-shelf wearable AR display was utilized by a remotely located surgeon to synchronously guide a nonsurgeon through proximal control of the distal external iliac artery on a surgical manikin. The manikin wound pattern was selected to simulate a rapidly exsanguinating junctional hemorrhage not controllable by nonsurgical means.ResultsThis capability demonstration displayed successful use of AR technology, telecommunication, and procedural training and guidance in a single test pilot. The assisted physician assistant was able to rapidly control the simulated external iliac artery injury on this model. The telestration system used was commercially available for use with available civilian cell phone, wireless and satellite networks, without the need for dedicated high-speed networks.ConclusionsA nonsurgeon, using a wearable commercial on-visual-axis telestration system, successfully performed a damage control procedure, demonstrating the plausibility of this approach.
- Published
- 2019
15. Influence of Mulching Systems on Yield and Quality of Southern Highbush Blueberries
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J. B. Magee and J. M. Spiers
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- 2018
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16. Measurement of the normalized U238(n,f)/U235(n,f) cross section ratio from threshold to 30 MeV with the NIFFTE fission Time Projection Chamber
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D. Higgins, N. S. Bowden, N. Hertel, F. Tovesson, D. Hensle, L. Yao, B. Wendt, C. Brune, W. Younes, K. T. Schmitt, L. D. Isenhower, M. Heffner, J. Ruz, H. Qu, N. Walsh, U. Hager, T. Classen, J. Baker, E. Guardincerri, J. S. Barrett, J. King, S. Sangiorgio, A. B. Laptev, D. A. Cebra, S. Sharma, M. Lynch, B. Seilhan, V. Geppert-Kleinrath, W. S. Lynn, M. Cunningham, R. Meharchand, R. S. Towell, L. Wood, T. Hill, S. Stave, A. C. Tate, W. Loveland, G. Tatishvili, S. Grimes, T. N. Massey, L. Snyder, J. Bundgaard, B. Manning, J. L. Klay, U. Greife, S. Watson, J. A. Magee, J. Gearhart, D. M. Asner, I. Ferguson, C. McGrath, J. Deaven, D. E. Towell, R. G. Baker, L. Montoya, D. L. Duke, C. Hagmann, R. Kudo, N. Kornilov, E. Burgett, R. T. Thornton, M. P. Mendenhall, R. J. Casperson, and N. T. Pickle
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Nuclear physics ,Normalization (statistics) ,Physics ,Time projection chamber ,010308 nuclear & particles physics ,Fission ,Ionization ,0103 physical sciences ,Neutron ,MicroMegas detector ,010306 general physics ,01 natural sciences ,Neutron temperature - Abstract
The normalized $^{238}$U(n,f)/$^{235}$U(n,f) cross section ratio has been measured using the NIFFTE fission Time Projection Chamber from the reaction threshold to $30$~MeV. The fissionTPC is a two-volume MICROMEGAS time projection chamber that allows for full three-dimensional reconstruction of fission-fragment ionization profiles from neutron-induced fission. The measurement was performed at the Los Alamos Neutron Science Center, where the neutron energy is determined from neutron time-of-flight. The $^{238}$U(n,f)/$^{235}$U(n,f) ratio reported here is the first cross section measurement made with the fissionTPC, and will provide new experimental data for evaluation of the $^{238}$U(n,f) cross section, an important standard used in neutron-flux measurements. Use of a development target in this work prevented the determination of an absolute normalization, to be addressed in future measurements. Instead, the measured cross section ratio has been normalized to ENDF/B-VIII.$\beta$5 at 14.5 MeV.
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- 2018
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17. Identifying Opportunities for Virtual Reality Simulation in Surgical Education
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Ming C. Lin, Jaisa Olasky, Andinet Enquobahrie, J. Harvey Magee, L. Michael Brunt, Suvranu De, Daniel B. Jones, Caroline G. L. Cao, Steven D. Schwaitzberg, Neal E. Seymour, Rajesh Aggarwal, and Ganesh Sankaranarayanan
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medicine.medical_specialty ,Engineering ,business.industry ,Human factors and ergonomics ,Virtual reality ,Credentialing ,Surgical training ,Article ,Innovation design ,Surgery ,User-Computer Interface ,Image-guided surgery ,Surgery, Computer-Assisted ,Task Performance and Analysis ,medicine ,Humans ,Computer Simulation ,Ergonomics ,Surgical education ,Technical skills ,business - Abstract
Objectives. To conduct a review of the state of virtual reality (VR) simulation technology, to identify areas of surgical education that have the greatest potential to benefit from it, and to identify challenges to implementation. Background Data. Simulation is an increasingly important part of surgical training. VR is a developing platform for using simulation to teach technical skills, behavioral skills, and entire procedures to trainees and practicing surgeons worldwide. Questions exist regarding the science behind the technology and most effective usage of VR simulation. A symposium was held to address these issues. Methods. Engineers, educators, and surgeons held a conference in November 2013 both to review the background science behind simulation technology and to create guidelines for its use in teaching and credentialing trainees and surgeons in practice. Results. Several technologic challenges were identified that must be overcome in order for VR simulation to be useful in surgery. Specific areas of student, resident, and practicing surgeon training and testing that would likely benefit from VR were identified: technical skills, team training and decision-making skills, and patient safety, such as in use of electrosurgical equipment. Conclusions. VR simulation has the potential to become an essential piece of surgical education curriculum but depends heavily on the establishment of an agreed upon set of goals. Researchers and clinicians must collaborate to allocate funding toward projects that help achieve these goals. The recommendations outlined here should guide further study and implementation of VR simulation.
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- 2015
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18. The economic cost of nonepileptic attack disorder in Ireland
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Teresa Burke, Gillian M. Fortune, J A Magee, Niall Pender, and Norman Delanty
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medicine.medical_specialty ,Population ,Behavioral Neuroscience ,Cost of Illness ,Seizures ,Chart review ,Economic cost ,Prevalence ,medicine ,Cost of illness ,Humans ,Psychiatry ,education ,health care economics and organizations ,Psychological treatment ,Retrospective Studies ,education.field_of_study ,Health economics ,business.industry ,Incidence ,Incidence (epidemiology) ,Health Care Costs ,Neurology ,Neurology (clinical) ,business ,Ireland - Abstract
The present study endeavored to calculate a conservative estimate of both incidence- and prevalence-based costs of nonepileptic attack disorder (NEAD) in Ireland by applying previously identified prevalence figures to Irish population figures. Variables related to the economic cost of NEAD were identified based on a retrospective chart review of patients diagnosed with NEAD at Beaumont Hospital, Dublin. The annual cost per patient of undiagnosed NEAD was calculated as €20,995.30. The combined cost of diagnosis and psychological treatment of NEAD was estimated at €8728. Although it is difficult to determine precise economic costings, early diagnosis and intervention would result in a significant economic saving to the exchequer, a reduction in hospital waiting-list times, and a better prognosis for patients.
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- 2014
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19. Interferon-γ release assays in the diagnosis of active tuberculosis disease in a low-incident setting: a 5-year review of data
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T.W. Lavender, Anne Barrett, J G Magee, and E.L.C. Ong
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Quantiferon Gold ,Adult ,Male ,Microbiology (medical) ,medicine.medical_specialty ,Tuberculosis ,Adolescent ,Interferon gamma release assay ,Disease ,Sensitivity and Specificity ,Young Adult ,Interferon γ ,Predictive Value of Tests ,Internal medicine ,Humans ,Medicine ,Young adult ,interferon gamma release assay ,Aged ,Aged, 80 and over ,business.industry ,Incidence (epidemiology) ,General Medicine ,Middle Aged ,Active tuberculosis ,medicine.disease ,United Kingdom ,Active disease ,Infectious Diseases ,Predictive value of tests ,low incident setting ,Immunology ,Female ,business ,Interferon-gamma Release Tests - Abstract
The role of interferon-γ release assays in the diagnosis of active tuberculosis disease is uncertain, and recent guidelines do not support their routine use. We reviewed the clinical records of 415 patients who had a QuantiFERON-TB Gold In-Tube assay between 29 June 2005 and 28 October 2010 to determine its performance in the diagnosis of active tuberculosis disease in a low prevalence setting, specifically in human immunodeficiency virus (HIV) -positive and HIV-negative patients, those of UK and non-UK origin, and those with pulmonary and extrapulmonary disease. For the diagnosis of active tuberculosis disease the overall sensitivity of QuantiFERON-TB Gold In-Tube assay was 71.4% (95% CI 59.3–81.1), specificity was 81.0% (95% CI 75.5–85.6) and negative predictive value was 92.6% (95% CI 88.2–95.5). No significant difference in sensitivity was seen in culture-positive and culture-negative tuberculosis, in pulmonary and extrapulmonary disease, or with HIV infection. Specificity and negative predictive value were significantly higher in patients of UK origin compared with those of non-UK origin (89.3% (95% CI 83.3–93.3) and 97.1% (95% CI 92.7–98.9) versus 66.3% (95% CI 55.6–75.5) and 83.3% (95% CI 72.6–90.4)). Our study suggests that there may be a role for interferon-γ release assays in excluding active tuberculosis disease, particularly extrapulmonary disease, in patients originating from areas of low tuberculosis incidence, with a negative test highly predictive of a lack of active tuberculosis disease in this group. We cannot support the use of these assays in the diagnosis of active tuberculosis infection in patients from areas of higher incidence.
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- 2013
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20. Beaufort trout MicroPlex: a high-throughput multiplex platform comprising 38 informative microsatellite loci for use in resident and anadromous (sea trout) brown trout Salmo trutta genetic studies
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Paulo A. Prodöhl, J. J. Magee, Rosaleen Hynes, Russell Poole, Kevin Keenan, Caroline Bradley, Richard J. Kennedy, Thomas F. Cross, W. W. Crozier, and Philip McGinnity
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Genetics ,Fish migration ,education.field_of_study ,biology ,Population ,Population genetics ,Aquatic Science ,biology.organism_classification ,Trout ,Brown trout ,Evolutionary biology ,Genetic variation ,Microsatellite ,Salmo ,education ,Ecology, Evolution, Behavior and Systematics - Abstract
A flexible panel consisting of 38 informative microsatellite markers for Salmo trutta is described. These markers were selected from a pool of over 150 candidate loci that can be readily amplified in four multiplex PCR groups but other permutations are also possible. The basic properties of each markers were assessed in six population samples from both the Burrishoole catchment, in the west of Ireland, and Lough Neagh, in Northern Ireland. A method to assess the relative utility of individual markers for the detection of population genetic structuring is also described. Given its flexibility, technical reliability and high degree of informativeness, the use of this panel of markers is advocated as a standard for S. trutta genetic studies.
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- 2013
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21. The ${Q^{p}_{\rm Weak}}$ experiment
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P. Solvignon, Wouter Deconinck, Riad Suleiman, D. G. Meekins, V. M. Gray, M. Poelker, J. A. Magee, S. Yang, S. Wells, Amrendra Narayan, R. T. Jones, T. Averett, B. Waidyawansa, D. Gaskell, Jean-Francois Rajotte, K. E. Myers, S. Kowalski, W. S. Duvall, William A. Tobias, M. K. Jones, W. T. H. van Oers, J. W. Martin, F. Guo, Joseph Grames, W. R. Falk, Kent Paschke, K. Grimm, J. Balewski, D. S. Armstrong, G. R. Smith, S. Covrig, J. A. Dunne, K. Johnston, V. Tadevosyan, P. Wang, Fatiha Benmokhtar, J. Mei, Vladimir Nelyubin, T. A. Forest, M. Kargiantoulakis, J. Leacock, J.C. Cornejo, M. M. Dalton, A.K. Opper, A. Mkrtchyan, Darko Androić, R. Silwal, V. Tvaskis, M. J. McHugh, W. D. Ramsay, L. Lee, Neven Simicevic, P. M. King, R. Mahurin, R. S. Beminiwattha, Michael Gericke, D. Zou, S. Zhamkochyan, J. Diefenbach, N. Nuruzzaman, Dipangkar Dutta, Roger Carlini, S. K. Phillips, D. T. Spayde, A. M. Micherdzinska, S. A. Page, M. H. Shabestari, J. R. Hoskins, D. C. Jones, Michael Pitt, Ross D. Young, Jongmin Lee, J. Birchall, Jay Benesch, K. A. Dow, L. Z. Ndukum, J. F. Dowd, A. R. Lee, Juliette Mammei, R. Michaels, J. M. Finn, J. Pan, J. Leckey, A. Asaturyan, A. Subedi, S. A. Wood, M. Elaasar, H. Mkrtchyan, C. A. Davis, D. J. Mack, S. MacEwan, T. Seva, E. Korkmaz, B. Sawatzky, J. Beaufait, R. Subedi, and J. Roche
- Subjects
Quark ,Physics ,Nuclear and High Energy Physics ,Particle physics ,Proton ,media_common.quotation_subject ,Physics beyond the Standard Model ,Momentum transfer ,Weinberg angle ,Parity (physics) ,Electron ,Condensed Matter Physics ,Asymmetry ,Atomic and Molecular Physics, and Optics ,Nuclear physics ,Physical and Theoretical Chemistry ,media_common - Abstract
In May 2012, the $Q^{p}_{\rm Weak}$ collaboration completed a two year measurement program to determine the weak charge of the proton ${Q^{p}_W} = ( 1 - 4\sin^2{\theta_{W}})$ at the Thomas Jefferson National Accelerator Facility (TJNAF). The experiment was designed to produce a 4.0 % measurement of the weak charge, via a 2.5 % measurement of the parity violating asymmetry in the number of elastically scattered 1.165 GeV electrons from protons, at forward angles. At the proposed precision, the experiment would produce a 0.3 % measurement of the weak mixing angle at a momentum transfer of Q 2 = 0.026 GeV2, making it the most precise stand alone measurement of the weak mixing angle at low momentum transfer. In combination with other parity measurements, $Q^{p}_{\rm Weak}$ will also provide a high precision determination of the weak charges of the up and down quarks. At the proposed precision, a significant deviation from the Standard Model prediction could be a signal of new physics at mass scales up to ≃ 6 TeV, whereas agreement would place new and significant constraints on possible Standard Model extensions at mass scales up to ≃ 2 TeV. This paper provides an overview of the physics and the experiment, as well as a brief look at some preliminary diagnostic and analysis data.
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- 2013
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22. A Qualitative Evaluation of Program Budgeting and Marginal Analysis in a Canadian Pediatric Tertiary Care Institution
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Mary-Ann Hiltz, J. Fergall Magee, Laura Dowling, Craig Mitton, Shashi Gujar, Neale Smith, and Matthew Campbell
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Program evaluation ,Budgets ,Economics and Econometrics ,media_common.quotation_subject ,Health administration ,Interviews as Topic ,Tertiary Care Centers ,03 medical and health sciences ,0302 clinical medicine ,Nursing ,Health care ,Medicine ,Humans ,Quality (business) ,030212 general & internal medicine ,Hospital Costs ,Child ,media_common ,Medical education ,Health economics ,business.industry ,030503 health policy & services ,Health Policy ,Middle management ,General Medicine ,Hospitals, Pediatric ,Nova Scotia ,Evaluation Studies as Topic ,Resource allocation ,0305 other medical science ,business ,Strengths and weaknesses ,Program Evaluation - Abstract
Hospitals in Canada are being asked by governments to improve efficiency and do more with fewer resources. Healthcare decision makers are thus driven to find better ways to manage budgets and deliver on their mission. Formal processes of priority setting and resource allocation (PSRA) are one means to this end. This paper reports an evaluation of one such approach, Program Budgeting and Marginal Analysis (PBMA), as applied at a children and women’s tertiary care facility in Nova Scotia, Canada. A brief evaluation conducted immediately after the conclusion of the PBMA process was supplemented with a larger retrospective evaluation. The retrospective evaluation included 26 face-to-face individual interviews with senior and middle managers who took part in PBMA. Interview transcripts were analyzed against a template consisting of 19 elements of structure, process, attitudes, and outcomes associated with high performance in PSRA. Respondents had a good experience with the implementation of PBMA, and considered it an improvement over past practice. Success was attributed to effective leadership, and substantial efforts to engage staff members. Understanding of economic and ethical principles of decision making was reportedly increased. Areas for improvement included ensuring that everyone participated in good faith, better communication of final results, and stronger follow-through to determine if anticipated changes and benefits in fact occurred. The evaluation framework employed here proved useful in assessing the quality of this resource allocation exercise. The results are directly useful to local decision makers, and the identified strengths and weaknesses are broadly consistent with those reported in studies of other organizations.
- Published
- 2016
23. The Qweak experiment: An overview and preliminary analysis
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J. A. Magee
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Quark ,Physics ,Nuclear physics ,Particle physics ,Proton ,Physics beyond the Standard Model ,media_common.quotation_subject ,Neutron ,Charge (physics) ,Electric charge ,Asymmetry ,Standard Model ,media_common - Abstract
The Qweak experiment completed data taking at Jefferson Laboratory in 2012, with the aim of making the first experimental determination of the proton’s weak charge, QWp, which is the neutral-weak analog of the proton’s electric charge. The experiment measured the small parity-violating asymmetry in elastic electron-proton scattering at forward angles and low momentum-transfer (Q2=0.026(GeV /c)2), allowing direct extraction of QWp. Once extracted, the current results directly probe potential new parity-violating semi-leptonic physics beyond the Standard Model at the TeV scale. In this paper we focus on the implications of the current Qweak experimental results, including the extraction of the proton and neutron weak charges, the individual quark weak-vector couplings, C1u and C1d, and also highlight the mass-limit reach of Standard Model extensions probed. An experimental overview will be provided, along with preliminary results from the first period of data-taking, which comprises 4% of the total data set...
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- 2016
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24. The tracking analysis in the Q-weak experiment
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T. Averett, M. M. Dalton, A.K. Opper, W. D. Ramsay, D. T. Spayde, K. Johnston, Kent Paschke, J. Mei, J.C. Cornejo, William A. Tobias, F. Guo, P. M. King, W. R. Falk, Vladimir Nelyubin, S. A. Wood, R. Mahurin, J. Leacock, Fatiha Benmokhtar, D. J. Mack, Jean-Francois Rajotte, S. A. Page, D. G. Meekins, J. Pan, Michael Gericke, S. Wells, S. Kowalski, J. Balewski, W. S. Duvall, J. Leckey, R. T. Jones, A. Mkrtchyan, M. H. Shabestari, J. W. Martin, Nuruzzaman, M. Elaasar, C. A. Davis, L. Z. Ndukum, B. Sawatzky, M. Kargiantoulakis, J. Grames, J. A. Magee, Roger Carlini, S. K. Phillips, P. Solvignon, G. D. Cates, S. Yang, Jongmin Lee, D. C. Jones, J. Diefenbach, N. Morgan, Wouter Deconinck, W. T. H. van Oers, Darko Androić, R. Michaels, V. M. Gray, A. R. Lee, B. Waidyawansa, S. MacEwan, T. Seva, E. Korkmaz, Jay Benesch, V. Tvaskis, J. Beaufait, R. Subedi, A. Asaturyan, R. Suleiman, S. Zhamkochyan, K. E. Myers, H. Mkrtchyan, D. S. Armstrong, G. R. Smith, J. A. Dunne, P. Wang, L. Lee, Dipangkar Dutta, K. Grimm, A. Subedi, S. Covrig, M. J. McHugh, Michael Pitt, Neven Simicevic, J. M. Finn, J. R. Hoskins, J. Roche, J. Birchall, T. A. Forest, Juliette Mammei, A. Micherdzinska, V. Tadevosyan, M. K. Jones, R. Silwal, Amrendra Narayan, M. Poelker, D. Gaskell, R. S. Beminiwattha, Ross D. Young, and J. F. Dowd
- Subjects
Physics ,Nuclear and High Energy Physics ,Particle physics ,Spectrometer ,business.industry ,Scattering ,media_common.quotation_subject ,Momentum transfer ,Tracking system ,Parity (physics) ,Kinematics ,Electron ,Condensed Matter Physics ,01 natural sciences ,Asymmetry ,Atomic and Molecular Physics, and Optics ,010305 fluids & plasmas ,Nuclear physics ,q-weak experiment ,0103 physical sciences ,Physical and Theoretical Chemistry ,010306 general physics ,business ,Nuclear Experiment ,media_common - Abstract
The Q-weak experiment at Jefferson Laboratory measured the parity violating asymmetry (A P V ) in elastic electron-proton scattering at small momentum transfer squared (Q 2=0.025 (G e V/c)2), with the aim of extracting the proton’s weak charge ( ${Q^p_W}$ ) to an accuracy of 5 %. As one of the major uncertainty contribution sources to ${Q^p_W}$ , Q 2 needs to be determined to ∼1 % so as to reach the proposed experimental precision. For this purpose, two sets of high resolution tracking chambers were employed in the experiment, to measure tracks before and after the magnetic spectrometer. Data collected by the tracking system were then reconstructed with dedicated software into individual electron trajectories for experimental kinematics determination. The Q-weak kinematics and the analysis scheme for tracking data are briefly described here. The sources that contribute to the uncertainty of Q 2 are discussed, and the current analysis status is reported.
- Published
- 2016
25. Changing Epidemiology of Clostridium difficile Infection Following the Introduction of a National Ribotyping-Based Surveillance Scheme in England
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J G Magee, Katherine J. Hardy, Warren N. Fawley, Pietro G Coen, M. Shemko, Martin D. Curran, Mark H. Wilcox, A. Birtles, K. J. Dodgson, S. M. Green, M. Cairns, Nandini Shetty, Mike W Wren, Peter M Hawkey, and A. D. Sails
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Adult ,Male ,Microbiology (medical) ,medicine.medical_specialty ,Adolescent ,genetic structures ,medicine.drug_class ,Cephalosporin ,Ribotyping ,Microbiology ,Feces ,Internal medicine ,Epidemiology ,Prevalence ,medicine ,Humans ,Public Health Surveillance ,Typing ,Child ,Epidemic strain ,Aged ,Aged, 80 and over ,Clostridioides difficile ,business.industry ,Incidence (epidemiology) ,Infant ,Middle Aged ,Clostridium difficile ,Anti-Bacterial Agents ,Infectious Diseases ,England ,Child, Preschool ,Clostridium Infections ,Female ,business - Abstract
BACKGROUND: Marked increases in Clostridium difficile infection (CDI) incidence, driven by epidemic strain spread, is a global phenomenon. METHODS: The Clostridium difficile Ribotyping Network (CDRN) was established in 2007 as part of enhanced CDI surveillance in England, to facilitate the recognition and control of epidemic strains. We report on changes in CDI epidemiology in England in the first 3 years of CDRN. RESULTS: CDRN received 12,603 fecal specimens, comprising significantly (P < .05) increasing numbers and proportions of national CDI cases in 2007-2008 (n = 2109, 3.8%), 2008-2009 (n = 4774, 13.2%), and 2009-2010 (n = 5720, 22.3%). The C. difficile recovery rate was 90%, yielding 11,294 isolates for ribotyping. Rates of 9 of the 10 most common ribotypes changed significantly (P < .05) during 2007-2010. Clostridium difficile ribotype 027 predominated, but decreased markedly from 55% to 36% and 21% in 2007-2008, 2008-2009, and 2009-2010, respectively. The largest regional variations in prevalence occurred for ribotypes 027, 002, 015, and 078. Cephalosporin and fluoroquinolone use in CDI cases was reported significantly (P < .05) less frequently during 2007-2010. Mortality data were subject to potential reporting bias, but there was a significant decrease in CDI-associated deaths during 2007-2010, which may have been due to multiple factors, including reduced prevalence of ribotype 027. CONCLUSIONS: Access to C. difficile ribotyping was associated with significant changes in the prevalence of epidemic strains, especially ribotype 027. These changes coincided with markedly reduced CDI incidence and related mortality in England. CDI control programs should include prospective access to C. difficile typing and analysis of risk factors for CDI and outcomes.
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- 2012
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26. Investigating Transmission of Mycobacterium bovis in the United Kingdom in 2005 to 2008
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Anne Barrett, Richard M. Myers, Francis Drobniewski, Oliver Blatchford, Louise Bradshaw, Sema Mandal, Ibrahim Abubakar, Peter M. Hawkey, P. Lewis White, J G Magee, Laura F Anderson, Tim Brown, Jason T. Evans, Amie Louise Seagar, Michael Ruddy, Grace Smith, and Ian F. Laurenson
- Subjects
Adult ,Male ,Microbiology (medical) ,medicine.medical_specialty ,Pathology ,Tuberculosis ,Adolescent ,Biology ,Young Adult ,Epidemiology ,medicine ,Cluster Analysis ,Humans ,Typing ,Aged ,Aged, 80 and over ,Molecular Epidemiology ,Mycobacterium bovis ,Molecular epidemiology ,Incidence ,Incidence (epidemiology) ,Outbreak ,Mycobacteriology and Aerobic Actinomycetes ,Middle Aged ,medicine.disease ,biology.organism_classification ,DNA Fingerprinting ,Virology ,United Kingdom ,Bacterial Typing Techniques ,Molecular Typing ,Cross-Sectional Studies ,DNA profiling ,Female - Abstract
Due to an increase in bovine tuberculosis in cattle in the United Kingdom, we investigated the characteristics of Mycobacterium bovis infection in humans and assessed whether extensive transmission of M. bovis between humans has occurred. A cross-sectional study linking demographic, clinical, and DNA fingerprinting (using 15-locus mycobacterial interspersed repetitive-unit–variable-number tandem-repeat [MIRU-VNTR] typing) data on cases reported between 2005 and 2008 was undertaken. A total of 129 cases of M. bovis infection in humans were reported over the period, with a decrease in annual incidence from 0.065 to 0.047 cases per 100,000 persons. Most patients were born pre-1960, before widespread pasteurization was introduced (73%), were of white ethnicity (83%), and were born in the United Kingdom (76%). A total of 102 patients (79%) had MIRU-VNTR typing data. A total of 31 of 69 complete MIRU-VNTR profiles formed eight distinct clusters. The overall clustering proportion determined using the n − 1 method was 33%. The largest cluster, comprising 12 cases, was indistinguishable from a previously reported West Midlands outbreak strain cluster and included those cases. This cluster was heterogeneous, having characteristics supporting recent zoonotic and human-to-human transmission as well as reactivation of latent disease. Seven other, smaller clusters identified had demographics supporting recrudescence rather than recent infection. A total of 33 patients had incomplete MIRU-VNTR profiles, of which 11 may have yielded 2 to 6 further small clusters if typed to completion. The incidence of M. bovis in humans in the United Kingdom remains low, and the epidemiology is predominantly that of reactivated disease.
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- 2011
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27. Parental views on tissue banking in pediatric oncology patients
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Louise Parker, Christa Kozancyzn, Robert B. Fraser, Conrad V. Fernandez, J. Fergall Magee, and Britney McMurter
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Pediatrics ,medicine.medical_specialty ,Ethical issues ,business.industry ,media_common.quotation_subject ,Childhood cancer ,Hematology ,Blood cancer ,Oncology ,Age of majority ,Family medicine ,Pediatrics, Perinatology and Child Health ,medicine ,Pediatric oncology ,Dissent ,business ,Uncertain significance ,Tissue Banking ,media_common - Abstract
Purpose Research using banked tissue is key to advancing risk-stratification and treatment of children with cancer. Knowledge of parental attitudes to ethical issues arising in tissue banking is very limited but essential in obtaining respectful consent. Methods One hundred parents of consecutively diagnosed children with cancer were offered a validated 34-item questionnaire. Results Respondents (n = 54) included 10 of 16 parents of deceased children. The majority (89%; n = 48) would agree to have tissue sent anywhere in the world but prefer pediatric aims (69%). Most (98%; n = 53) would permit genetic research, if it might improve the child's health, and 76% (n = 41) would permit it, even if no impact was anticipated. A minority (41%) would not allow painful, strictly research procedures, while 15% would regardless of the child's dissent. Just over half (54%; n = 29) wish to renew consent if stored tissue is used for another purpose. Most (98%) believe their child should confirm consent by the age of majority, but only 71% believe the mature child should be able to withdraw consent. A minority (n = 40; 74%) claim few or no rights to research profits; 83% believe these should be used to fund childhood cancer research. Conclusions Parents are very supportive of tissue research, including genetic research. A majority of parents would prefer restricting research to pediatric conditions, and to be informed of results, even if of uncertain significance. These findings may assist Institutional Review Boards in assessing parentally perceived risks of research, and researchers in providing consent elements that support parents and adolescents in making fully informed choices. Pediatr Blood Cancer 2011; 57: 1217–1221. © 2011 Wiley Periodicals, Inc.
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- 2011
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28. Extensively drug-resistant tuberculosis in the UK: 1995 to 2007
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Jonathan E. Moore, Charlotte Anderson, Tim Brown, J G Magee, Jim McMenamin, JM Watson, Michelle E. Kruijshaar, E G Smith, Francis Drobniewski, Michael Ruddy, Ibrahim Abubakar, M Yates, and Marc Lipman
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Adult ,Male ,Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Tuberculosis ,Capreomycin ,Extensively Drug-Resistant Tuberculosis ,Antitubercular Agents ,Microbial Sensitivity Tests ,Drug resistance ,Young Adult ,Drug Resistance, Multiple, Bacterial ,Internal medicine ,Tuberculosis, Multidrug-Resistant ,Case fatality rate ,medicine ,Humans ,Retrospective Studies ,Aged, 80 and over ,business.industry ,Extensively drug-resistant tuberculosis ,Retrospective cohort study ,Middle Aged ,medicine.disease ,United Kingdom ,Surgery ,Treatment Outcome ,Amikacin ,Female ,Ethionamide ,business ,medicine.drug - Abstract
Background: The emergence of multidrug-resistant tuberculosis (MDRTB) and extensively drug-resistant tuberculosis (XDRTB) is a threat to global tuberculosis control. Limited information is, however, available on the outcome of XDRTB cases. This study describes the susceptibility to second- and third-line antituberculosis drugs among MDRTB cases and treatment outcome of identified XDRTB cases. Method: The results of second-line antituberculosis drug susceptibility tests in the UK between January 1995 and December 2007 were retrospectively reviewed and clinicians contacted for treatment outcome of XDRTB cases. Participants included all 678 patients with culture-confirmed MDRTB in the UK. The main outcome measures were the proportion of isolates resistant to second-line antituberculosis drugs and treatment outcome for XDRTB cases. Results: Among MDRTB isolates, levels of resistance to amikacin, capreomycin, ciprofloxacin, cycloserine, ethionamide and p-aminosalicylic acid (PAS) were 5.5, 3.4, 5.6, 5.1, 14.0 and 16.7%, respectively. Six XDRTB cases (0.9% of MDR cases) were identified during this period. Two further cases of XDRTB were reported in 2008. Five individuals with XDRTB died of tuberculosis within 3 years of diagnosis and three are still on treatment. Conclusion: Levels of MDRTB remain low, and those of XDRTB very low, in this high income country. The case fatality ratio among XDRTB cases was high despite low levels of HIV co-infection.
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- 2009
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29. Mapping moderate-scale land-cover over very large geographic areas within a collaborative framework: A case study of the Southwest Regional Gap Analysis Project (SWReGAP)
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W. Rieth, Bruce C. Thompson, J. Prior-Magee, C. Velasquez, R.D. Ramsey, B. Wolk, Eric K. Waller, D. Schrupp, S. Falzarano, Kenneth G. Boykin, Gerald S. Manis, Jessica Kirby, S. Schrader, Kathryn A. Thomas, Cynthia S.A. Wallace, William G. Kepner, K. Pohs, L. O'Brien, David F. Bradford, L. Langs, Keith A. Schulz, Patrick J. Comer, John H. Lowry, and T. Sajwaj
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Geospatial analysis ,Data collection ,Geographic information system ,business.industry ,Decision tree learning ,Decision tree ,Soil Science ,Geology ,Land cover ,computer.software_genre ,Ecoregion ,Geography ,Gap Analysis Program ,Computers in Earth Sciences ,business ,computer ,Remote sensing - Abstract
Land-cover mapping efforts within the USGS Gap Analysis Program have traditionally been state-centered; each state having the responsibility of implementing a project design for the geographic area within their state boundaries. The Southwest Regional Gap Analysis Project (SWReGAP) was the first formal GAP project designed at a regional, multi-state scale. The project area comprises the southwestern states of Arizona, Colorado, Nevada, New Mexico, and Utah. The land-cover map/dataset was generated using regionally consistent geospatial data (Landsat ETM+ imagery (1999–2001) and DEM derivatives), similar field data collection protocols, a standardized land-cover legend, and a common modeling approach (decision tree classifier). Partitioning of mapping responsibilities amongst the five collaborating states was organized around ecoregion-based “mapping zones”. Over the course of 2 1 /2 field seasons approximately 93,000 reference samples were collected directly, or obtained from other contemporary projects, for the land-cover modeling effort. The final map was made public in 2004 and contains 125 landcover classes. An internal validation of 85 of the classes, representing 91% of the land area was performed. Agreement between withheld samples and the validated dataset was 61% (KHAT=.60, n=17,030). This paper presents an overview of the methodologies used to create the regional land-cover dataset and highlights issues associated with large-area mapping within a coordinated, multi-institutional management framework.
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- 2007
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30. High-speed source-synchronous interface for the IBM System z9 processor
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Jonathan Y. Chen, F. D. Ferraiolo, Derrin M. Berger, G. A. Van Hubert, and J. A. Magee
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IBM SAN Volume Controller ,General Computer Science ,Computer science ,business.industry ,Interface (computing) ,Clock rate ,Source-synchronous ,computer.software_genre ,Queued Telecommunications Access Method ,Operating system ,Cache ,IBM ,business ,computer ,Word (computer architecture) ,Computer hardware - Abstract
As mainframes evolve and deliver higher performance, technologists are focusing less on processor speed and more on overall system performance to create optimized systems. One important area of focus for performance improvement involves chip-to-chip interconnects, with their associated bandwidths and latencies. IBM and related computer manufacturers are optimizing the characteristics of interconnects between processors as well as between processors and their supporting chip sets (local cache, memory, I/O bridge). This paper describes the IBM proprietary high-speed interface known as Elastic Interface (EI), which is used for nearly all chip-to-chip communication in the IBM System z9TM. In particular, EI is a generic high-speed, source-synchronous interface used to transfer addresses, controls, and data between CPUs, L2 caches, memory subsystems, switches, and I/O hubs. The EI has single-ended data lines, resulting in twice the performance (bandwidth per pin) of similar buses operating with two differential lines per signal.
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- 2007
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31. Olly Olly Oxen Free (or Ally Ally in Free): Playing Hide and Seek in Allocating Resources for Child and Youth Health
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Matthew Campbell, Jennifer L. Gibson, J. Fergall Magee, Laura Dowling, Neale Smith, Mary-Ann Hiltz, Shashi Gujar, Craig Mitton, and Adrian R. Levy
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Canada ,Priority setting ,Health Care Rationing ,Adolescent ,business.industry ,Process (engineering) ,Health Priorities ,Hide and seek ,Child Health Services ,Public relations ,Investment (macroeconomics) ,Health care rationing ,Adolescent Health Services ,Resource allocation ,Humans ,Sociology ,Public engagement ,business ,Child ,Diversity (business) - Abstract
There are powerful arguments for increased investment in child and youth health. But the extent to which these benefits can be realized is shaped by health institutions' priority setting processes. We asked, "What are the unique features of a pediatric care setting that should influence choice and implementation of a formal priority setting and resource allocation process?" Based on multiple sources of data, we created a "made-for-child-health" lens containing three foci reflective of the distinct features of pediatric care settings: the diversity of child and youth populations, the challenges in measuring outcomes and the complexity of patient and public engagement.
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- 2015
32. Eye dosimetry and protective eyewear for interventional clinicians
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J S Magee, Charlotta Lundh, Viktor Sandblom, Anja Almén, and Colin J. Martin
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medicine.medical_specialty ,Medical staff ,Protective eyewear ,Quality Assurance, Health Care ,Radiology, Interventional ,Radiation Dosage ,Optics ,Radiation Protection ,Occupational Exposure ,Lens, Crystalline ,Medical Staff ,Medicine ,Dosimetry ,Humans ,Radiology, Nuclear Medicine and imaging ,Medical physics ,Radiation Injuries ,Radiometry ,Radiation ,Dosimeter ,Radiological and Ultrasound Technology ,Anthropometry ,business.industry ,Phantoms, Imaging ,Protective Devices ,X-Rays ,Public Health, Environmental and Occupational Health ,General Medicine ,Radiation Exposure ,Occupational Injuries ,Clinical Practice ,Eye Protective Devices ,Lead ,Dose reduction ,Radiation protection ,business - Abstract
Doses to the eyes of interventional clinicians can exceed 20 mSv. Various protective devices can afford protection to the eyes with the final barrier being protective eyewear. The protection provided by lead glasses is difficult to quantify, and the majority of dosimeters are not designed to be worn under lead glasses. This study has measured dose reduction factors (DRFs) equal to the ratio of the dose with no protection, divided by that when lead glasses are worn. Glasses have been tested in X-ray fields using anthropomorphic phantoms to simulate the patient and clinician. DRFs for X-rays incident from the front vary from 5.2 to 7.6, while values for orientations reminiscent of clinical practice are between 1.4 and 5.2. Results suggest that a DRF of two is a conservative factor that could be applied to personal dosimeter measurements to account for the dose reduction provided by most types of lead glasses.
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- 2015
33. The Qweak experimental apparatus
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J. R. Hoskins, R. S. Beminiwattha, J. Birchall, J. Diefenbach, Juliette Mammei, J. Balewski, Erik Urban, J. F. Dowd, K. Johnston, G. Clark, P.W. Rose, B. Sawatzky, P. Solvignon, M. Kargiantoulakis, M. Elaasar, J. Mei, S. Sobczynski, A. Micherdzinska, A. Kubera, M. K. Jones, R.B. Zielinski, Mitchell D. Anderson, T. Averett, R. Suleiman, V. M. Gray, E. Henderson, R.D. Carlini, S. A. Wood, Neven Simicevic, J. D. Bowman, A. Mkrtchyan, Amber McCreary, Darko Androić, V. Tvaskis, E. Bonnell, N. Morgan, R. Mahurin, Kent Paschke, R. Averill, J. Beaufait, J. Roche, S. Zhamkochyan, D. J. Mack, C. A. Davis, Fatiha Benmokhtar, S. A. Page, D.C. Dean, J. M. Finn, P. Medeiros, Jean-Francois Rajotte, R. Subedi, G. D. Cates, S. Wells, F. Guo, S. MacEwan, P. Wang, J. A. Dunne, Jongmin Lee, T. Seva, E. Korkmaz, S. K. Phillips, D. C. Jones, P. Brindza, Amrendra Narayan, M. Poelker, J. Pan, J. Leacock, A. R. Lee, V. Tadevosyan, D. Gaskell, Y. Liang, R. Michaels, M. M. Dalton, D.J. Harrison, A.K. Opper, J. Grames, M. McDonald, S. Kowalski, J.C. Cornejo, W. S. Duvall, W. D. Ramsay, A. Asaturyan, J. Leckey, K. Grimm, J. W. Martin, B. Stokes, P. M. King, Michael Gericke, K. E. Mesick, H. Mkrtchyan, E. Ihloff, J. A. Magee, Nadeem A. Khan, L. Lee, J. Kelsey, Trent Allison, Jay Benesch, S. Yang, D. T. Spayde, B. Waidyawansa, D.B. Brown, S. Covrig Dusa, Dipangkar Dutta, W. R. Falk, R. Silwal, A. Subedi, Vladimir Nelyubin, J. Bessuille, D. G. Meekins, R. T. Jones, J. Hansknecht, Nuruzzaman, W. T. H. van Oers, K.D. Finelli, Michael Pitt, J.R. Echols, D. S. Armstrong, G. R. Smith, Douglas Storey, M. J. McHugh, M. H. Shabestari, J. Musson, K. A. Dow, L. Z. Ndukum, Wouter Deconinck, W.R. Roberts, William A. Tobias, and B. S. Cavness
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Physics ,Nuclear and High Energy Physics ,business.industry ,Compton scattering ,Collimator ,Electron ,Helicity ,law.invention ,Nuclear physics ,Optics ,Beamline ,law ,Scintillation counter ,Cathode ray ,Physics::Accelerator Physics ,Parity violation ,Electron scattering ,Liquid hydrogen target ,business ,Instrumentation ,Cherenkov radiation - Abstract
The Jefferson Lab Q weak experiment determined the weak charge of the proton by measuring the parity-violating elastic scattering asymmetry of longitudinally polarized electrons from an unpolarized liquid hydrogen target at small momentum transfer. A custom apparatus was designed for this experiment to meet the technical challenges presented by the smallest and most precise e → p asymmetry ever measured. Technical milestones were achieved at Jefferson Lab in target power, beam current, beam helicity reversal rate, polarimetry, detected rates, and control of helicity-correlated beam properties. The experiment employed 180 μA of 89% longitudinally polarized electrons whose helicity was reversed 960 times per second. The electrons were accelerated to 1.16 GeV and directed to a beamline with extensive instrumentation to measure helicity-correlated beam properties that can induce false asymmetries. Moller and Compton polarimetry were used to measure the electron beam polarization to better than 1%. The electron beam was incident on a 34.4 cm liquid hydrogen target. After passing through a triple collimator system, scattered electrons between 5.8° and 11.6° were bent in the toroidal magnetic field of a resistive copper-coil magnet. The electrons inside this acceptance were focused onto eight fused silica Cherenkov detectors arrayed symmetrically around the beam axis. A total scattered electron rate of about 7 GHz was incident on the detector array. The detectors were read out in integrating mode by custom-built low-noise pre-amplifiers and 18-bit sampling ADC modules. The momentum transfer Q 2 =0.025 GeV 2 was determined using dedicated low-current ( ~ 100 pA ) measurements with a set of drift chambers before (and a set of drift chambers and trigger scintillation counters after) the toroidal magnet.
- Published
- 2015
34. studies of renal homotransplantation in man*
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D. M. Hume, J. H. Magee, G. R. Prout, H. M. Kauflman, R. H. Cleveland, J. D. Bower, and H. M. Lee
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History and Philosophy of Science ,General Neuroscience ,General Biochemistry, Genetics and Molecular Biology - Published
- 2006
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35. Effects of duplicate and screening isolates on surveillance of community and hospital antibiotic resistance
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J. T. Magee
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Microbiology (medical) ,Veterinary medicine ,medicine.drug_class ,Antibiotics ,Hospital Departments ,medicine.disease_cause ,Microbiology ,Antibiotic resistance ,Bias ,Drug Resistance, Bacterial ,medicine ,Humans ,Infection control ,Pharmacology (medical) ,Antibacterial agent ,Susceptibility pattern ,Pharmacology ,Cross Infection ,Wales ,business.industry ,Confidence interval ,Community-Acquired Infections ,Infectious Diseases ,Staphylococcus aureus ,Data Interpretation, Statistical ,Population Surveillance ,Flucloxacillin ,Epidemiologic Methods ,business ,medicine.drug - Abstract
OBJECTIVES To investigate common contentions that duplicate and screening isolates consistently show marked excess resistance, and that inclusion of such isolates significantly distorts regional resistance estimates. METHODS Two Welsh surveys of antibiotic resistance for routine diagnostic isolates were analysed, comprising 309,129 isolates of six common community pathogens and 85,061 ward isolates of 11 common hospital pathogens. Duplicate isolates were defined as isolates from the same patient of the same pathogen with an indistinguishable susceptibility pattern, excluding the initial isolate. Significance was assessed from 95% confidence limits of the difference between resistance estimates. RESULTS Duplicate isolates comprised approximately 20% of total isolates. For the 195 antibiotic-pathogen combinations investigated, differences in resistance between duplicate and non-duplicate isolates were statistically significant for 93. Only 54 combinations showed significantly increased resistance amongst duplicates, and only 30 of these showed a difference >5%. Comparisons of de-duplicated with un-de-duplicated regional resistance estimates showed significant differences for only 18 of 195 antibiotic-pathogen combinations; none were sufficient to alter judgement on clinical use. Screening isolates produced little disturbance of resistance estimates for Staphylococcus aureus, with the exception of flucloxacillin resistance, where inclusion of screening and duplicate isolates resulted in an increase of 4.4% for both community and hospital resistance estimates. CONCLUSIONS The contentions were incorrect for these regional surveys. However, the proportion (and so effects) of screening and duplicate isolates may be greater in surveys of units with frequent repetitive sampling practice (burns, ITU, cystic fibrosis), or pathogens subjected to unusually intensive infection control sampling.
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- 2004
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36. The IBM eServer z990 microprocessor
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Erwin Pfeffer, J. A. Magee, and T. J. Siegel
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Coprocessor ,Serviceability (computer) ,General Computer Science ,Computer science ,business.industry ,Translation lookaside buffer ,Cryptography ,computer.software_genre ,law.invention ,Microprocessor ,law ,Superscalar ,Operating system ,IBM ,Error detection and correction ,business ,computer - Abstract
The IBM eServerTM z990 microprocessor implements many features designed to give excellent performance on both newer and traditional mainframe applications. These features include a new superscalar instruction execution pipeline, high-bandwidth caches, a huge secondary translation-lookaside buffer (TLB), and an onboard cryptographic coprocessor. The microprocessor maintains zSeries® leadership in RAS (reliability, availability, serviceability) capabilities that include state-of-the-art error detection and recovery.
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- 2004
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37. The use of rpoB sequence analysis in the differentiation of Mycobacterium abscessus and Mycobacterium chelonae: a critical judgement in cystic fibrosis?
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J G Magee, C. Arnold, A. Barrett, and L. Cross
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DNA, Bacterial ,Microbiology (medical) ,Sequence analysis ,medicine.medical_treatment ,Mycobacterium Infections, Nontuberculous ,Mycobacterium chelonae ,Mycobacterium abscessus ,Cystic fibrosis ,Microbiology ,cystic fibrosis ,Species Specificity ,medicine ,Humans ,Lung transplantation ,Gene ,Sequence (medicine) ,biology ,Nontuberculous Mycobacteria ,Sequence Analysis, DNA ,sequencing ,General Medicine ,bacterial infections and mycoses ,biology.organism_classification ,rpoB ,medicine.disease ,Bacterial Typing Techniques ,Infectious Diseases ,M. abscessus ,M. chelonae ,RNA Polymerase II - Abstract
Individuals suffering from fibrocystic disease may acquire non-tuberculous mycobacteria as colonizing or infecting organisms. Mycobacterium abscessus is of particular concern because it may be very difficult to eradicate and may mitigate against lung transplantation. However, this species may be difficult to reliably differentiate from the closely related M. chelonae. We have developed a rapid, low-cost, short sequence-based technique to confirm species identity by analysis of a segment of the RNA Polymerase B (rpoB) gene.
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- 2012
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38. An evaluation of the BD ProbeTec ET system for the direct detection of Mycobacterium tuberculosis in respiratory samples
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Roger Freeman, Anne Barrett, and J G Magee
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Microbiology (medical) ,Bacteriological Techniques ,Tuberculosis ,biology ,Repeat testing ,Multiple displacement amplification ,Molecular Probe Techniques ,Early detection ,Mycobacterium tuberculosis ,General Medicine ,biology.organism_classification ,medicine.disease ,Sensitivity and Specificity ,Microbiology ,Mycobacterium tuberculosis complex ,Predictive Value of Tests ,Positive predicative value ,medicine ,Humans ,Tuberculosis, Pulmonary ,Respiratory samples - Abstract
In controlling the spread of tuberculosis, early detection of disease caused by organisms of the Mycobacterium tuberculosis complex (MTBC) is vital. The BD ProbeTec ET system provides a method for the direct detection of MTBC by strand displacement amplification. Two hundred and five respiratory samples from patients with a high probability of tuberculosis were assessed by ProbeTec and by microscopy and culture for mycobacteria. ProbeTec positive results were obtained with 101 of 109 samples from which MTBC organisms were isolated. ProbeTec correctly signalled 78 of 81 samples that gave growths of mycobacteria other than tubercle bacilli (MOTT) as negative. Three samples gave false-positive results, corrected on repeat testing. Positive and negative predictive values (PPV, NPV) were 0.97 and 0.90 and the system showed a sensitivity and specificity of 92.7% and 96.0%, respectively. These values rose to PPV 0.97, NPV 0.96, sensitivity 97.1% and specificity 96.0% when data from the small number of gastric lavage samples tested were removed from the analysis. The BD ProbeTec ET system offers a robust and reliable molecular biological approach to the detection of MTBC organisms in respiratory samples in a semi-automated format.
- Published
- 2002
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39. A national study of clinical and laboratory factors affecting the survival of patients with multiple drug resistant tuberculosis in the UK
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B Watt, Francis Drobniewski, C Graham, J G Magee, E G Smith, and I Eltringham
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Adult ,Male ,Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Tuberculosis ,Adolescent ,medicine.drug_class ,medicine.medical_treatment ,Antibiotics ,Antitubercular Agents ,Immunocompromised Host ,Internal medicine ,Tuberculosis, Multidrug-Resistant ,medicine ,Humans ,Risk factor ,Child ,Survival analysis ,Aged ,Proportional Hazards Models ,Chemotherapy ,Proportional hazards model ,business.industry ,Infant, Newborn ,Sputum ,Infant ,Middle Aged ,medicine.disease ,Survival Analysis ,United Kingdom ,Surgery ,Child, Preschool ,Relative risk ,Female ,Original Article ,medicine.symptom ,business - Abstract
Background: This study aimed to describe the clinical, microbiological, molecular epidemiology and treatment of multidrug resistant tuberculosis (MDRTB) cases in the UK and to determine factors associated with survival. Methods: Ninety MDRTB cases were identified from 1 January 1996 to 30 June 1997; 69 were DNA fingerprinted. Date of diagnosis was determined and data were collated on key demographic factors, clinical, radiological and treatment details. Variables associated with survival were included in a Cox proportional hazards model. Results: Most of the patients (72.4%) were male, born outside the UK (57.1%), were sputum smear positive (82.2%), and had entered the UK more than 5 years previously (61.9%). Thirty eight of 78 cases (48.7%) had prior TB. Sufficient data on 82 patients were available for survival analysis; 20/27 (74.1%) known to be dead at the end of the observation period had died of tuberculosis. Median survival time overall was 1379 days (95% CI 1336 to 2515) or 3.78 (95% CI 3.66 to 6.89) years (858 days (95% CI 530 to 2515) in immunocompromised individuals (n=32) and 1554 (95% CI 1336 to 2066) days in immunocompetent cases (n=48)). Median survival in patients treated with three drugs to which the bacterium was susceptible on in vitro testing (n=62) was 2066 days (95% CI 1336 to 2515) or 5.66 years, whereas in those not so treated (n=13) survival was 599 days (95% CI 190 to 969) or 1.64 years. Conclusions: Immunocompromised status, failure to culture the bacterium in 30 days or to apply appropriate three drug treatment, and age were significant factors in mortality. An immunocompromised patient was nearly nine times more likely to die, while application of appropriate treatment reduced the risk (risk ratio 0.06). Increasing age was associated with increasing risk of death (risk ratio 2.079; 95% CI 1.269 to 3.402)—that is, for every 10 year increase in age the risk almost doubled. Overall survival was lower than that reported in previous studies.
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- 2002
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40. Qweak: First Direct Measurement of the Proton’s Weak Charge
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J. R. Hoskins, V. Tadevosyan, J. Diefenbach, K. Johnston, J. Birchall, S.A. Page, D. S. Armstrong, M. J. McHugh, J. Mei, H. Nuhait, C. A. Davis, M. Elaasar, Juliette Mammei, T. Averett, Wouter Deconinck, J. A. Magee, P. Wang, S. Yang, G.R. Smith, W. R. Falk, P. Zang, H. Mkrtchyan, W. T. H. van Oers, D. G. Meekins, J. Pan, F. Guo, J. Roche, Vladimir Nelyubin, W.D. Ramsay, J. Beaufait, B. Sawatzky, Fatiha Benmokhtar, M.L. Pitt, D. C. Jones, N. Morgan, R. Suleiman, N. Simicevic, V. Tvaskis, R. Michaels, Michael Gericke, B. Waidyawansa, Roger Carlini, J. Leckey, T. A. Forest, R. T. Jones, Jay Benesch, J. M. Finn, J. Balewski, M. M. Dalton, J. Grames, L. Lee, Jean-Francois Rajotte, Dipangkar Dutta, S. Kowalski, L. Z. Ndukum, W. S. Duvall, D. J. Mack, J. W. Martin, A.K. Opper, M. Kargiantoulakis, S.A. Wood, T. Seva, P. Solvignon, G. D. Cates, V. M. Gray, Jongmin Lee, K. Grimm, S. Covrig, A. R. Lee, J. Leacock, R. Mahurin, D.T. Spayde, R. Silwal, A. Mkrtchyan, S.K. Phillips, A. Asaturyan, S. Zhamkochyan, S. MacEwan, E. Korkmaz, J.C. Cornejo, K. E. Myers, P. M. King, K. Bartlett, Darko Androić, A. Subedi, J. A. Dunne, Amrendra Narayan, R. Subedi, D. Gaskell, K.D. Paschke, A. Micherdzinska, M.H. Shabestari, M. K. Jones, W.A. Tobias, C. Gal, R. S. Beminiwattha, M. Poelker, Ross D. Young, J. F. Dowd, and S.P. Wells
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Physics ,Particle physics ,Proton ,010308 nuclear & particles physics ,QC1-999 ,media_common.quotation_subject ,Hadron ,Charge (physics) ,Elementary particle ,7. Clean energy ,01 natural sciences ,Asymmetry ,Standard Model ,Nuclear physics ,0103 physical sciences ,Physics::Accelerator Physics ,Grand Unified Theory ,Nuclear Experiment ,010306 general physics ,Nucleon ,media_common - Abstract
The Q weak experiment, which took data at Jefferson Lab in the period 2010 - 2012, will precisely determine the weak charge of the proton by measuring the parity-violating asymmetry in elastic e-p scattering at 1.1 GeV using a longitudinally polarized electron beam and a liquid hydrogen target at a low momentum transfer of Q 2 = 0.025 (GeV/c)2 . The weak charge of the proton is predicted by the Standard Model and any significant deviation would indicate physics beyond the Standard Model. The technical challenges and experimental apparatus for measuring the weak charge of the proton will be discussed, as well as the method of extracting the weak charge of the proton. The results from a small subset of the data, that has been published, will also be presented. Furthermore an update will be given of the current status of the data analysis.
- Published
- 2017
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41. Early Results from the Qweak Experiment
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J. Beaufait, H. Mkrtchyan, J. Roche, J. A. Dunne, Jean-Francois Rajotte, Kathryn Grimm, S. K. Phillips, J. Diefenbach, S. Covrig, S. MacEwan, T. Seva, E. Korkmaz, D. G. Meekins, Matthew Jones, M. M. Dalton, T. Averett, D. C. Jones, Kent Paschke, R. W. L. Jones, Fatiha Benmokhtar, J. A. Magee, R. Michaels, P. M. King, W. D. Ramsay, R. S. Beminiwattha, M. H. Shabestari, Wouter Deconinck, V. Tadevosyan, A. Asaturyan, R. D. Carlini, S. Kowalski, W. S. Duvall, Jay Benesch, F. Guo, J. Birchall, A. Micherdzinska, Joseph Grames, Ross D. Young, J. W. Martin, B. Waidyawansa, J. F. Dowd, Michael Pitt, S. Yang, Geoffrey Smith, S. A. Page, V. M. Gray, M. Poelker, Nuruzzaman, R. Silwal, G. D. Cates, P. Wang, S. P. Wells, T. A. Forest, Jongmin Lee, Dipangkar Dutta, K. Johnston, A. R. Lee, J. Leacock, B. Sawatzky, M. Elaasar, J. Mei, D. S. Armstrong, Riad Suleiman, A. Subedi, S. A. Wood, R. Mahurin, Amrendra Narayan, L. Lee, J. Balewski, P. Solvignon, D. J. Mack, R. Subedi, John M. Finn, W. R. Falk, M. Kargiantoulakis, N. Morgan, L. Z. Ndukum, Vladimir Nelyubin, M. J. McHugh, Neven Simicevic, W. T. H. van Oers, C. A. Davis, William A. Tobias, D. Gaskel, Michael Gericke, J. C. Cornejo, J. R. Hoskins, J. Pan, Darko Androić, Juliette Mammei, S. Zhamkochyan, J. Leckey, D. T. Spayde, A. K. Opper, K. E. Myers, V. Tvaskis, and A. Mkrtchyan
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Physics ,Quark ,Scattering ,media_common.quotation_subject ,Physics beyond the Standard Model ,QC1-999 ,FOS: Physical sciences ,Electron ,Measure (mathematics) ,Asymmetry ,Nuclear physics ,Neutron ,High Energy Physics::Experiment ,Nuclear Experiment (nucl-ex) ,Nuclear Experiment ,Beam (structure) ,media_common - Abstract
A subset of results from the recently completed Jefferson Lab Qweak experiment are reported. This experiment, sensitive to physics beyond the Standard Model, exploits the small parity-violating asymmetry in elastic ep scattering to provide the first determination of the protons weak charge Qweak(p). The experiment employed a 180 uA longitudinally polarized 1.16 GeV electron beam on a 35 cm long liquid hydrogen target. Scattered electrons corresponding to Q2 of 0.025 GeV2 were detected in eight Cerenkov detectors arrayed symmetrically around the beam axis. The goals of the experiment were to provide a measure of Qweak(p) to 4.2 percent (combined statistical and systematic error), which implies a measure of sin2(thetaw) at the level of 0.3 percent, and to help constrain the vector weak quark charges C1u and C1d. The experimental method is described, with particular focus on the challenges associated with the worlds highest power LH2 target. The new constraints on C1u and C1d provided by the subset of the experiments data analyzed to date will also be shown, together with the extracted weak charge of the neutron., Comment: 8 pages, 4 figures, INPC2013
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- 2014
42. Identifying sputum specimens of high priority for examination by enhanced mycobacterial detection, identification, and susceptibility systems (EMDISS) to promote the rapid diagnosis of infectious pulmonary tuberculosis
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A Barrett, Roger Freeman, and J G Magee
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Bacteriological Techniques ,Tuberculosis ,biology ,business.industry ,Liquid culture ,Mycobacterial culture ,Respiratory disease ,Sputum ,Mycobacterium tuberculosis ,General Medicine ,medicine.disease ,biology.organism_classification ,Specimen Handling ,Pathology and Forensic Medicine ,Pulmonary tuberculosis ,Papers ,Immunology ,Acid-fast ,Humans ,Medicine ,medicine.symptom ,business ,Tuberculosis, Pulmonary - Abstract
Aims—To compare clinical information and sputum microscopy as methods for the selection of samples for enhanced mycobacterial detection, identification, and susceptibility systems (EMDISS) to promote the rapid diagnosis of patients with infectious pulmonary tuberculosis. Methods—Two thousand, two hundred and sixty four specimen request forms were examined for clinical details, which were then used to identify specimens likely to yield Mycobacterium tuberculosis on culture. These results were compared with the results of sputum microscopy for acid fast bacilli (AFB). Both methods were assessed against the results of culture using a combination of continuous automated mycobacterial liquid culture (CAMLiC) and conventional solid culture. Results—Classification based on clinical details was an inefficient method of identifying high priority specimens for EMDISS. Although, when given, clinical details were often consistent, a substantial proportion of specimens arrived with no details. This approach would result in the referral of at least 16% of the workload but lead to the detection by culture of only 46% of the M tuberculosis present within it. In contrast, microscopy for AFB defined a much smaller number of specimens (4.8% of the total), which contained 90% of the M tuberculosis isolates. Conclusions—Microscopy for AFB is the most efficient method for defining sputum specimens suitable for referral for enhanced mycobacteriological techniques. However, it is essential that the methods used for smear preparation and microscopy are of the highest possible standard, otherwise some patients with infectious pulmonary tuberculosis will be denied, unnecessarily, the benefits of important advances in mycobacteriology. Key Words: tuberculosis • diagnosis • AFB smear • mycobacterial culture
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- 2001
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43. [Untitled]
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J. A. Magee, Stephen D. McCormick, T. A. Haines, K. F. Beland, and John F. Kocik
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geography ,Environmental Engineering ,geography.geographical_feature_category ,biology ,Ecological Modeling ,Estuary ,biology.organism_classification ,Pollution ,River water ,Hatchery ,Fishery ,Animal science ,Osmoregulation ,Environmental Chemistry ,Atpase activity ,Ultrasonic telemetry ,Seawater ,Salmo ,Water Science and Technology - Abstract
Atlantic salmon, Salmo salar, smolts of hatchery origin were held for 5 to 16 days in ambient (pH 6.35, labile Al = 60 µg L−1), limed (pH 6.72, labile Al = 58.4 µg L−1), or acidified (pH 5.47, labile Al=96 µg L−1) water from the Narraguagus River in Maine, USA. Wild smolts were captured in the same river in rotary traps and held for up to two days in ambient river water. Osmoregulatory ability was assessed by measuring Na+/K+ ATPase activity, hematocrit, and blood Cl concentration in freshwater, and after 24-hr exposure to seawater. Hatchery smolts exposed to acidic water and wild smolts displayed sub-lethal ionoregulatory stress both in fresh and seawater, with mortalities of wild smolts in seawater. Using ultrasonic telemetry, hatchery-reared ambient and acid-exposed, and wild smolts were tracked as they migrated through freshwater and estuarine sections of the river. The proportion of wild smolts migrating during daylight hours was higher than for hatchery-reared smolts. Wild smolts remained in the freshwater portions of the river longer than either group of hatchery smolts, although survival during migration to seawater was similar for all three treatments. Acid-exposed hatchery-origin and wild Narraguagus River smolts were both under ionoregulatory stress that may have affected their migratory behavior, but not their survival for the time and area in which we tracked them.
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- 2001
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44. The diagnosis of ventilator-associated pneumonia using non-bronchoscopic, non-directed lung lavages
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Mark Smithies, J. T. Magee, A. Ionescu, Rosemary Ann Barnes, G. P. Findlay, and P. G. Flanagan
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Adult ,Male ,medicine.medical_specialty ,Critical Care and Intensive Care Medicine ,Predictive Value of Tests ,Intensive care ,Internal medicine ,medicine ,Humans ,Hospital Mortality ,Prospective Studies ,Prospective cohort study ,APACHE ,Wales ,Lung ,Bacteria ,medicine.diagnostic_test ,business.industry ,Respiratory disease ,Ventilator-associated pneumonia ,Pneumonia ,Middle Aged ,medicine.disease ,Respiration, Artificial ,respiratory tract diseases ,Surgery ,Intensive Care Units ,Bronchoalveolar lavage ,medicine.anatomical_structure ,Predictive value of tests ,Female ,business ,Bronchoalveolar Lavage Fluid - Abstract
Objectives: (1)To assess the diagnostic utility of quantitative cultures of non-bronchoscopic lung lavage (NBL) in ventilator-associated pneumonia and evaluate the role of the Bacterial Index; (2) To assess the predictive value of NBL surveillance quantitative cultures in ventilated patients; (3) To evaluate the Clinical Pulmonary Infection Score (CPIS) system in ventilated patients. Design: A prospective comparison of NBL with bronchoscopic bronchoalveolar lavage and protected specimen brush. Setting: Three intensive care units in academic tertiary care centres. Patients: 145 adults ventilated for 72 h, with and without clinical signs of pneumonia. Interventions: Sampling of lower airway secretions by NBL, bronchoalveolar lavage and protected specimen brush. Main outcome measures: Diagnostic reliability of quantitative cultures, Bacterial Index and CPIS. Results: 34 episodes of clinical ventilator-associated pneumonia were documented in 32 patients. 9 episodes were confirmed by concordant blood/pleural culture or post-mortem lung examination. Qualitative concordance of the predominant pathogen between sequential NBL: bronchoalveolar lavage and protected specimen brush was 83%. Sensitivity and specificity of non-directed bronchial lavage at a threshold of 104 CFU/ml were 68%and 70% respectively (p = 0.003) and were comparable with the bronchoscopic methods. However, the low positive predictive value of NBL indicates that quantitation in the absence of clinical signs is unlikely to be useful. Bacterial Index did not improve discriminatory power of quantitation compared with bacterial load of predominant organism. Mean CPIS for confirmed pneumonia cases was 8.4 - 1.01, significantly higher than for non-pneumonia observations (p = < 0.0001). Conclusion: NBL is a simple, safe, cheap, readily-available method of diagnosing ventilator-associated pneumonia with comparable diagnostic accuracy to bronchoscopic techniques. Quantitation of respiratory tract cultures can exclude pneumonia in patients with equivocal clinical signs. The diagnostic threshold should vary depending on the length of ventilation, likelihood of pneumonia and antibiotic administration. The Bacterial Index is a flawed mathematical device that has no contributory role in pneumonia diagnosis. The CPIS has some diagnostic role in selected cohorts of ventilated patients.
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- 2000
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45. Evaluation of the Cepheid Respiratory Syncytial Virus and Influenza Virus A/B real-time PCR analyte specific reagent
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David Saunders, G Eltringham, Stephanie Airs, David Roberts, J G Magee, and Andrew D. Sails
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viruses ,Orthomyxoviridae ,Respiratory Syncytial Virus Infections ,medicine.disease_cause ,Polymerase Chain Reaction ,Sensitivity and Specificity ,Article ,Virus ,Microbiology ,Virology ,Influenza, Human ,medicine ,Influenza A virus ,Humans ,Multiplex ,Evaluation ,Respiratory Tract Infections ,biology ,Influenzavirus B ,RSV ,virus diseases ,respiratory system ,biology.organism_classification ,Influenza A/B ,Detection ,Influenza B virus ,Respiratory Syncytial Virus, Human ,Indicators and Reagents ,Analyte-specific reagent ,Viral disease ,Rhinovirus ,Real-time PCR - Abstract
Two rapid real-time RT-PCR assays, specific for respiratory syncytial virus (RSV) and influenza A and B, were evaluated for the detection of these viruses in clinical respiratory samples. The RSV assay was applied to 100 samples and the Influenza A and B assay applied to 96 samples all of which had been tested previously by an "in-house" multiplex real-time PCR assay. Forty-three samples were negative for RSV by both methods and 56 samples were positive by both methods. One sample was negative by the new RSV assay although it was positive for RSV A by the "in-house" test. Thirty-nine samples were negative for influenza virus by both methods and 55 samples were positive by both assays. Two samples were negative by the new influenza assay however they were positive by the "in-house" influenza assay. The new assays did not cross react with samples containing other viruses including parainfluenza 1, 2, and 4; human metapnuemovirus; coronavirus 229E, NL63, OC43; rhinovirus; adenovirus; bocavirus and had a specificity of 100% and a sensitivity of 98.2% for RSV and 96.5% for influenza respectively. The results of this study demonstrate that the new assays are specific and sensitive for the detection of RSV and influenza viruses in clinical samples.
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- 2009
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46. Development of Amplified 16S Ribosomal DNA Restriction Analysis for Identification of Actinomyces Species and Comparison with Pyrolysis-Mass Spectrometry and Conventional Biochemical Tests
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Val Hall, Brian I. Duerden, G.L. O'Neill, and J. T. Magee
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DNA, Bacterial ,Microbiology (medical) ,HpaII ,Restriction Mapping ,DNA, Ribosomal ,Polymerase Chain Reaction ,Mass Spectrometry ,HaeIII ,Restriction fragment ,RNA, Ribosomal, 16S ,medicine ,Actinomyces ,Humans ,DNA, Fungal ,Ribosomal DNA ,Genetics ,biology ,Reproducibility of Results ,Mycobacteriology and Aerobic Actinomycetes ,Nucleic acid amplification technique ,16S ribosomal RNA ,biology.organism_classification ,Amplified Ribosomal DNA Restriction Analysis ,biology.protein ,Nucleic Acid Amplification Techniques ,medicine.drug - Abstract
Identification of Actinomyces spp. by conventional phenotypic methods is notoriously difficult and unreliable. Recently, the application of chemotaxonomic and molecular methods has clarified the taxonomy of the group and has led to the recognition of several new species. A practical and discriminatory identification method is now needed for routine identification of clinical isolates. Amplified 16S ribosomal DNA restriction analysis (ARDRA) was applied to reference strains ( n = 27) and clinical isolates ( n = 36) of Actinomyces spp. and other gram-positive rods. Clinical strains were identified initially to the species level by conventional biochemical tests. However, given the low degree of confidence in conventional methods, the findings obtained by ARDRA were also compared with those obtained by pyrolysis-mass spectrometry. The ARDRA profiles generated by the combination of Hae III and Hpa II endonuclease digestion differentiated all reference strains to the species or subspecies level. The profiles correlated well with the findings obtained by pyrolysis-mass spectrometry and by conventional tests and enabled the identification of 31 of 36 clinical isolates to the species level. ARDRA was shown to be a simple, rapid, cost-effective, and highly discriminatory method for routine identification of Actinomyces spp. of clinical origin.
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- 1999
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47. A national audit of the laboratory diagnosis of tuberculosis and other mycobacterial diseases within the United Kingdom
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J Holder, Randi M. Williams, E G Smith, B Watt, Francis Drobniewski, J Ostrowski, and J G Magee
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medicine.medical_specialty ,Tuberculosis ,Molecular Diagnostic Method ,Drug resistance ,Reference laboratory ,Tuberculous meningitis ,Pathology and Forensic Medicine ,Internal medicine ,Tuberculosis, Multidrug-Resistant ,medicine ,Humans ,National audit ,Decontamination ,Antibacterial agent ,Bacteriological Techniques ,Medical Audit ,Mycobacterium Infections ,business.industry ,Bacteriology ,General Medicine ,medicine.disease ,United Kingdom ,Surgery ,Genetic Techniques ,Laboratories ,business ,Rifampicin ,Research Article ,medicine.drug - Abstract
In order to audit United Kingdom laboratory diagnostic and reference services including novel molecular methods for tuberculosis, a questionnaire was sent to laboratories submitting specimens to the PHLS Mycobacterium Reference Unit (MRU) and regional centres and to the Scottish Mycobacteria Reference Laboratory (SMRL) in 1996-7. Nationally, 67.2% of laboratories responded. Most UK laboratories were fully or conditionally CPA accredited and take part in the NEQAS proficiency scheme. On average only 3.3% of primary samples submitted for mycobacterial diagnosis in 1995 produced a mycobacterial culture from approximately half as many patients (that is, a mean of 1488 specimens producing 49 isolates from 23 patients). Potentially over 380,000 specimens are processed for mycobacteria in the UK each year. The majority of laboratories use 4% NaOH +/- NALC for specimen decontamination. Culture on solid media was used by most laboratories and 62.9% also use liquid media. Most laboratories incubated cultures for eight weeks. Few laboratories use molecular diagnostic methods. Laboratories were most likely to use molecular methods for diagnosing tuberculous meningitis and for specimens from immunocompromised patients, although usage was strongly influenced by cost. Within England and Wales 43.9% (47/107) and 56% (61/109) of laboratories wanted a rapid service for rifampicin resistance detection in M tuberculosis from immunocompetent and immunocompromised patients, respectively. In regard to a tuberculous meningitis service, 80.5% (43/112) and 84.3% (102/121) of laboratories wanted this service for immunocompetent and immunocompromised patients, respectively. The quality of reference services was rated as "very good"/"good" by 85.6% of respondents nationally. Rapid molecular amplification diagnostic services were established at the PHLS MRU for rifampicin drug resistance detection nationally and for tuberculous meningitis at the MRU.
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- 1999
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48. The 1998 list Proposed new bacterial taxa and proposed changes of bacterial names published during 1998 and considered to be of interest to medical or veterinary bacteriology
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Wilhelm Frederiksen, J. T. Magee, and Jan Ursing
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Microbiology (medical) ,Taxon ,MEDLINE ,Bacteriology ,Immunology and Allergy ,Library science ,Taxonomy (biology) ,General Medicine ,Biology ,Pathology and Forensic Medicine - Published
- 1999
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49. Proposed new bacterial taxa and proposed changes of bacterial names published during 1997 and considered to be of interest to medical or veterinary bacteriology
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Jan Ursing, Wilhelm Frederiksen, and J. T. Magee
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Microbiology (medical) ,Bacteria ,Zoology ,General Medicine ,Biology ,Microbiology ,Bacterial strain ,Taxon ,Evolutionary biology ,Terminology as Topic ,Bacteriology ,Animals ,Humans ,Taxonomy (biology) - Abstract
A list of names of bacteria published or validated in 1997 is presented. Comments are made of the tendency to base names of new taxa on a single bacterial strain and the consequences for reliable descriptions that this tendency implies.
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- 1999
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50. The 1997 list
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Wilhelm Frederiksen, Jan Ursing, and J. T. Magee
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Veterinary Medicine ,Time Factors ,Bacteria ,Immunology ,Zoology ,Bacteriology ,Bacterial Infections ,General Medicine ,Biology ,Classification ,Microbiology ,Single strain ,Bacterial strain ,Genealogy ,Animal Diseases ,Geography ,Taxon ,Terminology as Topic ,Animals ,Humans ,Taxonomy (biology) - Abstract
A list of names published or validated in 1997 is presented. We also comment on the tendency to base names of new taxa on a single bacterial strain, and the consequences for reliable descriptions that this tendency implies.
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- 1998
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