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609 results on '"Waller, D. A."'

1. Bronchoscopic Lung Volume Reduction as the Treatment of Choice versus Robotic-Assisted Lung Volume Reduction Surgery in Similar Patients with Emphysema – An Initial Experience of the Benefits and Complications

Author

Lee M, Dhanji AR, Perikleous P, Baranowski R, Lau KKW, and Waller D

Subjects
lung volume reduction, lung volume reduction surgery, bronchoscopic lung volume reduction, endobronchial valve, emphysema, Diseases of the respiratory system, RC705-779
Abstract

Michelle Lee, Al-Rehan Dhanji, Periklis Perikleous, Ralitsa Baranowski, Kelvin Kar Wing Lau, David Waller Department of Thoracic Surgery, Barts Thorax Centre, St Bartholomew’s Hospital, London, UKCorrespondence: Michelle Lee, Department of Thoracic Surgery, St Bartholomew’s Hospital, West Smithfield, London, United Kingdom, Email m.lee7@nhs.netObjective: There is an assumption that because EBLVR requires less use of hospital resources, offsetting the higher cost of endobronchial valves, it should therefore be the treatment of choice wherever possible. We have tested this hypothesis in a retrospective analysis of the two in similar groups of patients.Methods: In a 4-year experience, we performed 177 consecutive LVR procedures: 83 patients underwent Robot Assisted Thoracoscopic (RATS) LVRS and 94 EBLVR. EBLVR was intentionally precluded by evidence of incomplete fissure integrity or intra-operative assessment of collateral ventilation. Unilateral RATS LVRS was performed in these cases together with those with unsuitable targets for EBLVR.Results: EBLVR was uncomplicated in 37 (39%) cases; complicated by post-procedure spontaneous pneumothorax (SP) in 28(30%) and required revision in 29 (31%). In the LVRS group, 7 (8%) patients were readmitted with treatment-related complications, but no revisional procedure was needed. When compared with uncomplicated EBLVR, LVRS had a significantly longer operating time: 85 (14– 82) vs 40 (15– 151) minutes (p< 0.001) and hospital stay: 7.5 (2– 80) vs 2 (1– 14) days (p< 0.01). However, LVRS had a similar total operating time to both EBLVR requiring revision: 78 (38– 292) minutes and hospital stay to EBLVR complicated by pneumothorax of 11.5 (6.5– 24.25) days. Use of critical care was significantly longer in RATS group, and it was also significantly longer in EBV with SP group than in uncomplicated EBV group.Conclusion: Endobronchial LVR does use less hospital resources than RATS LVRS in comparable groups if the recovery is uncomplicated. However, this advantage is lost if one includes the resources needed for the treatment of complications and revisional procedures. Any decision to favour EBLVR over LVRS should not be based on the assumption of a smoother, faster perioperative course.Keywords: lung volume reduction, lung volume reduction surgery, bronchoscopic lung volume reduction, endobronchial valve, emphysema

Published
2024

2. Search for $hep$ solar neutrinos and the diffuse supernova neutrino background using all three phases of the Sudbury Neutrino Observatory

Author

Aharmim, B., Ahmed, S. N., Anthony, A. E., Barros, N., Beier, E. W., Bellerive, A., Beltran, B., Bergevin, M., Biller, S. D., Blucher, E., Bonventre, R., Boudjemline, K., Boulay, M. G., Cai, B., Callaghan, E. J., Caravaca, J., Chan, Y. D., Chauhan, D., Chen, M., Cleveland, B. T., Cox, G. A., Dai, X., Deng, H., Descamps, F. B., Detwiler, J. A., Doe, P. J., Doucas, G., Drouin, P. -L., Dunford, M., Elliott, S. R., Evans, H. C., Ewan, G. T., Farine, J., Fergani, H., Fleurot, F., Ford, R. J., Formaggio, J. A., Gagnon, N., Gilje, K., Goon, J. TM., Graham, K., Guillian, E., Habib, S., Hahn, R. L., Hallin, A. L., Hallman, E. D., Harvey, P. J., Hazama, R., Heintzelman, W. J., Heise, J., Helmer, R. L., Hime, A., Howard, C., Huang, M., Jagam, P., Jamieson, B., Jelley, N. A., Jerkins, M., Keeter, K. J., Klein, J. R., Kormos, L. L., Kos, M., Kraus, C., Krauss, C. B., Krüger, A., Kutter, T., Kyba, C. C. M., Labe, K., Land, B. J., Lange, R., LaTorre, A., Law, J., Lawson, I. T., Lesko, K. T., Leslie, J. R., Levine, I., Loach, J. C., MacLellan, R., Majerus, S., Mak, H. B., Maneira, J., Martin, R. D., Mastbaum, A., McCauley, N., McDonald, A. B., McGee, S. R., Miller, M. L., Monreal, B., Monroe, J., Nickel, B. G., Noble, A. J., O'Keeffe, H. M., Oblath, N. S., Okada, C. E., Ollerhead, R. W., Gann, G. D. Orebi, Oser, S. M., Ott, R. A., Peeters, S. J. M., Poon, A. W. P., Prior, G., Reitzner, S. D., Rielage, K., Robertson, B. C., Robertson, R. G. H., Schwendener, M. H., Secrest, J. A., Seibert, S. R., Simard, O., Sinclair, D., Skensved, P., Sonley, T. J., Stonehill, L. C., Tešić, G., Tolich, N., Tsui, T., Van Berg, R., VanDevender, B. A., Virtue, C. J., Wall, B. L., Waller, D., Tseung, H. Wan Chan, Wark, D. L., Wendland, J., West, N., Wilkerson, J. F., Wilson, J. R., Winchester, T., Wright, A., Yeh, M., Zhang, F., and Zuber, K.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

A search has been performed for neutrinos from two sources, the $hep$ reaction in the solar $pp$ fusion chain and the $\nu_e$ component of the diffuse supernova neutrino background (DSNB), using the full dataset of the Sudbury Neutrino Observatory with a total exposure of 2.47 kton-years after fiducialization. The $hep$ search is performed using both a single-bin counting analysis and a likelihood fit. We find a best-fit flux that is compatible with solar model predictions while remaining consistent with zero flux, and set a one-sided upper limit of $\Phi_{hep} < 30\times10^{3}~\mathrm{cm}^{-2}~\mathrm{s}^{-1}$ [90% credible interval (CI)]. No events are observed in the DSNB search region, and we set an improved upper bound on the $\nu_e$ component of the DSNB flux of $\Phi^\mathrm{DSNB}_{\nu_e} < 19~\textrm{cm}^{-2}~\textrm{s}^{-1}$ (90% CI) in the energy range $22.9 < E_\nu < 36.9$~MeV., Comment: 11 pages, 6 figures

Published
2020
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3. Cosmogenic Neutron Production at the Sudbury Neutrino Observatory

Author

Aharmim, B., Ahmed, S. N., Anthony, A. E., Barros, N., Beier, E. W., Bellerive, A., Beltran, B., Bergevin, M., Biller, S. D., Bonventre, R., Boudjemline, K., Boulay, M. G., Cai, B., Callaghan, E. J., Caravaca, J., Chan, Y. D., Chauhan, D., Chen, M., Cleveland, B. T., Cox, G. A., Curley, R., Dai, X., Deng, H., Descamps, F. B., Detwiler, J. A., Doe, P. J., Doucas, G., Drouin, P. -L., Dunford, M., Elliott, S. R., Evans, H. C., Ewan, G. T., Farine, J., Fergani, H., Fleurot, F., Ford, R. J., Formaggio, J. A., Gagnon, N., Gilje, K., Goon, J. TM., Graham, K., Guillian, E., Habib, S., Hahn, R. L., Hallin, A. L., Hallman, E. D., Harvey, P. J., Hazama, R., Heintzelman, W. J., Heise, J., Helmer, R. L., Hime, A., Howard, C., Huang, M., Jagam, P., Jamieson, B., Jelley, N. A., Jerkins, M., Kéfélian, C., Keeter, K. J., Klein, J. R., Kormos, L. L., Kos, M., Kr\u, A., Kraus, C., Krauss, C. B., Kutter, T., Kyba, C. C. M., Land, B. J., Lange, R., Law, J., Lawson, I. T., Lesko, K. T., Leslie, J. R., Levine, I., Loach, J. C., MacLellan, R., Majerus, S., Mak, H. B., Maneira, J., Martin, R. D., Mastbaum, A., McCauley, N., McDonald, A. B., McGee, S. R., Miller, M. L., Monreal, B., Monroe, J., Nickel, B. G., Noble, A. J., O'Keeffe, H. M., Oblath, N. S., Okada, C. E., Ollerhead, R. W., Gann, G. D. Orebi, Oser, S. M., Ott, R. A., Peeters, S. J. M., Poon, A. W. P., Prior, G., Reitzner, S. D., Rielage, K., Robertson, B. C., Robertson, R. G. H., Schwendener, M. H., Secrest, J. A., Seibert, S. R., Simard, O., Sinclair, D., Skensved, P., Sonley, T. J., Stonehill, L. C., Teš, G., Tolich, N., Tsui, T., Van Berg, R., VanDevender, B. A., Virtue, C. J., Wall, B. L., Waller, D., Tseung, H. Wan Chan, Wark, D. L., Wendland, J., West, N., Wilkerson, J. F., Wilson, J. R., Winchester, T., Wright, A., Yeh, M., Zhang, F., and Zuber, K.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

Neutrons produced in nuclear interactions initiated by cosmic-ray muons present an irreducible background to many rare-event searches, even in detectors located deep underground. Models for the production of these neutrons have been tested against previous experimental data, but the extrapolation to deeper sites is not well understood. Here we report results from an analysis of cosmogenically produced neutrons at the Sudbury Neutrino Observatory. A specific set of observables are presented, which can be used to benchmark the validity of GEANT4 physics models. In addition, the cosmogenic neutron yield, in units of $10^{-4}\;\text{cm}^{2}/\left(\text{g}\cdot\mu\right)$, is measured to be $7.28 \pm 0.09\;\text{stat.} ^{+1.59}_{-1.12}\;\text{syst.}$ in pure heavy water and $7.30 \pm 0.07\;\text{stat.} ^{+1.40}_{-1.02}\;\text{syst.}$ in NaCl-loaded heavy water. These results provide unique insights into this potential background source for experiments at SNOLAB.

Published
2019
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4. Measurement of neutron production in atmospheric neutrino interactions at the Sudbury Neutrino Observatory

Author

SNO Collaboration, Aharmim, B., Ahmed, S. N., Anthony, A. E., Barros, N., Beier, E. W., Bellerive, A., Beltran, B., Bergevin, M., Biller, S. D., Bonventre, R., Boudjemline, K., Boulay, M. G., Cai, B., Callaghan, E. J., Caravaca, J., Chan, Y. D., Chauhan, D., Chen, M., Cleveland, B. T., Cox, G. A., Dai, X., Deng, H., Descamps, F. B., Detwiler, J. A., Doe, P. J., Doucas, G., Drouin, P. -L., Dunford, M., Elliott, S. R., Evans, H. C., Ewan, G. T., Farine, J., Fergani, H., Fleurot, F., Ford, R. J., Formaggio, J. A., Gagnon, N., Gilje, K., Goon, J. TM., Graham, K., Guillian, E., Habib, S., Hahn, R. L., Hallin, A. L., Hallman, E. D., Harvey, P. J., Hazama, R., Heintzelman, W. J., Heise, J., Helmer, R. L., Hime, A., Howard, C., Huang, M., Jagam, P., Jamieson, B., Jelley, N. A., Jerkins, M., Keeter, K. J., Klein, J. R., Kormos, L. L., Kos, M., Kruger, A., Kraus, C., Krauss, C. B., Kutter, T., Kyba, C. C. M., Land, B. J., Lange, R., Law, J., Lawson, I. T., Lesko, K. T., Leslie, J. R., Levine, I., Loach, J. C., MacLellan, R., Majerus, S., Mak, H. B., Maneira, J., Martin, R. D., Mastbaum, A., McCauley, N., McDonald, A. B., McGee, S. R., Miller, M. L., Monreal, B., Monroe, J., Nickel, B. G., Noble, A. J., O'Keeffe, H. M., Oblath, N. S., Okada, C. E., Ollerhead, R. W., Gann, G. D. Orebi, Oser, S. M., Ott, R. A., Peeters, S. J. M., Poon, A. W. P., Prior, G., Reitzner, S. D., Rielage, K., Robertson, B. C., Robertson, R. G. H., Schwendener, M. H., Secrest, J. A., Seibert, S. R., Simard, O., Sinclair, D., Singh, J., Skensved, P., Smiley, M., Sonley, T. J., Stonehill, L. C., Tesic, G., Tolich, N., Tsui, T., Van Berg, R., VanDevender, B. A., Virtue, C. J., Wall, B. L., Waller, D., Tseung, H. Wan Chan, Wark, D. L., Wendland, J., West, N., Wilkerson, J. F., Wilson, J. R., Winchester, T., Wright, A., Yeh, M., Zhang, F., and Zuber, K.

Subjects
High Energy Physics - Experiment
Abstract

Neutron production in GeV-scale neutrino interactions is a poorly studied process. We have measured the neutron multiplicities in atmospheric neutrino interactions in the Sudbury Neutrino Observatory experiment and compared them to the prediction of a Monte Carlo simulation using GENIE and a minimally modified version of GEANT4. We analyzed 837 days of exposure corresponding to Phase I, using pure heavy water, and Phase II, using a mixture of Cl in heavy water. Neutrons produced in atmospheric neutrino interactions were identified with an efficiency of $15.3\%$ and $44.3\%$, for Phase I and II respectively. The neutron production is measured as a function of the visible energy of the neutrino interaction and, for charged current quasi-elastic interaction candidates, also as a function of the neutrino energy. This study is also performed classifying the complete sample into two pairs of event categories: charged current quasi-elastic and non charged current quasi-elastic, and $\nu_{\mu}$ and $\nu_e$. Results show good overall agreement between data and Monte Carlo for both phases, with some small tension with a statistical significance below $2\sigma$ for some intermediate energies.

Published
2019
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5. Constraints on Neutrino Lifetime from the Sudbury Neutrino Observatory

Author

SNO Collaboration, Aharmim, B., Ahmed, S. N., Anthony, A. E., Barros, N., Beier, E. W., Bellerive, A., Beltran, B., Bergevin, M., Biller, S. D., Bonventre, R., Boudjemline, K., Boulay, M. G., Cai, B., Callaghan, E. J., Caravaca, J., Chan, Y. D., Chauhan, D., Chen, M., Cleveland, B. T., Cox, G. A., Dai, X., Deng, H., Descamps, F. B., Detwiler, J. A., Doe, P. J., Doucas, G., Drouin, P. -L., Dunford, M., Elliott, S. R., Evans, H. C., Ewan, G. T., Farine, J., Fergani, H., Fleurot, F., Ford, R. J., Formaggio, J. A., Gagnon, N., Gilje, K., Goon, J. TM., Graham, K., Guillian, E., Habib, S., Hahn, R. L., Hallin, A. L., Hallman, E. D., Harvey, P. J., Hazama, R., Heintzelman, W. J., Heise, J., Helmer, R. L., Hime, A., Howard, C., Huang, M., Jagam, P., Jamieson, B., Jelley, N. A., Jerkins, M., Kéfélian, C., Keeter, K. J., Klein, J. R., Kormos, L. L., Kos, M., Krüger, A., Kraus, C., Krauss, C. B., Kutter, T., Kyba, C. C. M., Land, B. J., Lange, R., Law, J., Lawson, I. T., Lesko, K. T., Leslie, J. R., Levine, I., Loach, J. C., MacLellan, R., Majerus, S., Mak, H. B., Maneira, J., Martin, R. D., Mastbaum, A., McCauley, N., McDonald, A. B., McGee, S. R., Miller, M. L., Monreal, B., Monroe, J., Nickel, B. G., Noble, A. J., O'Keeffe, H. M., Oblath, N. S., Okada, C. E., Ollerhead, R. W., Gann, G. D. Orebi, Oser, S. M., Ott, R. A., Peeters, S. J. M., Poon, A. W. P., Prior, G., Reitzner, S. D., Rielage, K., Robertson, B. C., Robertson, R. G. H., Schwendener, M. H., Secrest, J. A., Seibert, S. R., Simard, O., Sinclair, D., Skensved, P., Sonley, T. J., Stonehill, L. C., Tešić, G., Tolich, N., Tsui, T., Van Berg, R., VanDevender, B. A., Virtue, C. J., Wall, B. L., Waller, D., Tseung, H. Wan Chan, Wark, D. L., Wendland, J., West, N., Wilkerson, J. F., Wilson, J. R., Winchester, T., Wright, A., Yeh, M., Zhang, F., and Zuber, K.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

The long baseline between the Earth and the Sun makes solar neutrinos an excellent test beam for exploring possible neutrino decay. The signature of such decay would be an energy-dependent distortion of the traditional survival probability which can be fit for using well-developed and high precision analysis methods. Here a model including neutrino decay is fit to all three phases of $^8$B solar neutrino data taken by the Sudbury Neutrino Observatory. This fit constrains the lifetime of neutrino mass state $\nu_2$ to be ${>8.08\times10^{-5}}$ s/eV at $90\%$ confidence. An analysis combining this SNO result with those from other solar neutrino experiments results in a combined limit for the lifetime of mass state $\nu_2$ of ${>1.04\times10^{-3}}$ s/eV at $99\%$ confidence.

Published
2018
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6. Tests of Lorentz invariance at the Sudbury Neutrino Observatory

Author

SNO Collaboration, Aharmim, B., Ahmed, S. N., Anthony, A. E., Barros, N., Beier, E. W., Bellerive, A., Beltran, B., Bergevin, M., Biller, S. D., Blucher, E., Bonventre, R., Boudjemline, K., Boulay, M. G., Cai, B., Callaghan, E. J., Caravaca, J., Chan, Y. D., Chauhan, D., Chen, M., Cleveland, B. T., Cox, G. A., Dai, X., Deng, H., Descamps, F. B., Detwiler, J. A., Doe, P. J., Doucas, G., Drouin, P. -L., Dunford, M., Elliott, S. R., Evans, H. C., Ewan, G. T., Farine, J., Fergani, H., Fleurot, F., Ford, R. J., Formaggio, J. A., Gagnon, N., Gilje, K., Goon, J. TM., Graham, K., Guillian, E., Habib, S., Hahn, R. L., Hallin, A. L., Hallman, E. D., Harvey, P. J., Hazama, R., Heintzelman, W. J., Heise, J., Helmer, R. L., Hime, A., Howard, C., Huang, M., Jagam, P., Jamieson, B., Jelley, N. A., Jerkins, M., Kefelian, C., Keeter, K. J., Klein, J. R., Kormos, L. L., Kos, M., Kruger, A., Kraus, C., Krauss, C. B., Kutter, T., Kyba, C. C. M., Labe, K., Land, B. J., Lange, R., LaTorre, A., Law, J., Lawson, I. T., Lesko, K. T., Leslie, J. R., Levine, I., Loach, J. C., MacLellan, R., Majerus, S., Mak, H. B., Maneira, J., Martin, R. D., Mastbaum, A., McCauley, N., McDonald, A. B., McGee, S. R., Miller, M. L., Monreal, B., Monroe, J., Nickel, B. G., Noble, A. J., O'Keeffe, H. M., Oblath, N. S., Okada, C. E., Ollerhead, R. W., Gann, G. D. Orebi, Oser, S. M., Ott, R. A., Peeters, S. J. M., Poon, A. W. P., Prior, G., Reitzner, S. D., Rielage, K., Robertson, B. C., Robertson, R. G. H., Schwendener, M. H., Secrest, J. A., Seibert, S. R., Simard, O., Sinclair, D., Skensved, P., Sonley, T. J., Stonehill, L. C., Tesic, G., Tolich, N., Tsui, T., Van Berg, R., VanDevender, B. A., Virtue, C. J., Wall, B. L., Waller, D., Tseung, H. Wan Chan, Wark, D. L., Wendland, J., West, N., Wilkerson, J. F., Winchester, T., Wilson, J. R., Wright, A., Yeh, M., Zhang, F., and Zuber, K.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

Experimental tests of Lorentz symmetry in systems of all types are critical for ensuring that the basic assumptions of physics are well-founded. Data from all phases of the Sudbury Neutrino Observatory, a kiloton-scale heavy water Cherenkov detector, are analyzed for possible violations of Lorentz symmetry in the neutrino sector. Such violations would appear as one of eight possible signal types in the detector: six seasonal variations in the solar electron neutrino survival probability differing in energy and time dependence, and two shape changes to the oscillated solar neutrino energy spectrum. No evidence for such signals is observed, and limits on the size of such effects are established in the framework of the Standard Model Extension, including 40 limits on perviously unconstrained operators and improved limits on 15 additional operators. This makes limits on all minimal, Dirac-type Lorentz violating operators in the neutrino sector available for the first time.

Published
2018
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7. The search for neutron-antineutron oscillations at the Sudbury Neutrino Observatory

Author

SNO Collaboration, Aharmim, B., Ahmed, S. N., Anthony, A. E., Barros, N., Beier, E. W., Bellerive, A., Beltran, B., Bergevin, M., Biller, S. D., Boudjemline, K., Boulay, M. G., Cai, B., Chan, Y. D., Chauhan, D., Chen, M., Cleveland, B. T., Cox, G. A., Dai, X., Deng, H., Detwiler, J. A., Doe, P. J., Doucas, G., Drouin, P. -L., Duncan, F. A., Dunford, M., Earle, E. D., Elliott, S. R., Evans, H. C., Ewan, G. T., Farine, J., Fergani, H., Fleurot, F., Ford, R. J., Formaggio, J. A., Gagnon, N., Goon, J. TM., Graham, K., Guillian, E., Habib, S., Hahn, R. L., Hallin, A. L., Hallman, E. D., Harvey, P. J., Hazama, R., Heintzelman, W. J., Heise, J., Helmer, R. L., Hime, A., Howard, C., Huang, M., Jagam, P., Jamieson, B., Jelley, N. A., Jerkins, M., Keeter, K. J., Klein, J. R., Kormos, L. L., Kos, M., Kruger, A., Kraus, C., Krauss, C. B., Kutter, T., Kyba, C. C. M., Lange, R., Law, J., Lawson, I. T., Lesko, K. T., Leslie, J. R., Levine, I., Loach, J. C., MacLellan, R., Majerus, S., Mak, H. B., Maneira, J., Martin, R. D., McCauley, N., McDonald, A. B., McGee, S. R., Miller, M. L., Monreal, B., Monroe, J., Nickel, B. G., Noble, A. J., O'Keeffe, H. M., Oblath, N. S., Okada, C. E., Ollerhead, R. W., OrebiGann, G. D., Oser, S. M., Ott, R. A., Peeters, S. J. M., Poon, A. W. P., Prior, G., Reitzner, S. D., Rielage, K., Robertson, B. C., Robertson, R. G. H., Schwendener, M. H., Secrest, J. A., Seibert, S. R., Simard, O., Simpson, J. J., Sinclair, D., Skensved, P., Sonley, T. J., Stonehill, L. C., Tesic, G., Tolich, N., Tsui, T., Van Berg, R., VanDevender, B. A., Virtue, C. J., Wall, B. L., Waller, D., Tseung, H. Wan Chan, Wark, D. L., Wendland, J., West, N., Wilkerson, J. F., Wilson, J. R., Wright, A., Yeh, M., Zhang, F., and Zuber, K.

Subjects
High Energy Physics - Experiment, Nuclear Experiment, Physics - Instrumentation and Detectors
Abstract

Tests on $B-L$ symmetry breaking models are important probes to search for new physics. One proposed model with $\Delta(B-L)=2$ involves the oscillations of a neutron to an antineutron. In this paper a new limit on this process is derived for the data acquired from all three operational phases of the Sudbury Neutrino Observatory experiment. The search was concentrated in oscillations occurring within the deuteron, and 23 events are observed against a background expectation of 30.5 events. These translate to a lower limit on the nuclear lifetime of $1.48\times 10^{31}$ years at 90% confidence level (CL) when no restriction is placed on the signal likelihood space (unbounded). Alternatively, a lower limit on the nuclear lifetime was found to be $1.18\times 10^{31}$ years at 90% CL when the signal was forced into a positive likelihood space (bounded). Values for the free oscillation time derived from various models are also provided in this article. This is the first search for neutron-antineutron oscillation with the deuteron as a target., Comment: 14 pages, 8 figures

Published
2017
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9. A Search for Astrophysical Burst Signals at the Sudbury Neutrino Observatory

Author

Aharmim, B., Ahmed, S. N., Anthony, A. E., Barros, N., Beier, E. W., Bellerive, A., Beltran, B., Bergevin, M., Biller, S. D., Boudjemline, K., Boulay, M. G., Cai, B., Chan, Y. D., Chauhan, D., Chen, M., Cleveland, B. T., Cox, G. A., Dai, X., Deng, H., Detwiler, J. A., DiMarco, M., Diamond, M. D., Doe, P. J., Doucas, G., Drouin, P. -L., Duncan, F. A., Dunford, M., Earle, E. D., Elliott, S. R., Evans, H. C., Ewan, G. T., Farine, J., Fergani, H., Fleurot, F., Ford, R. J., Formaggio, J. A., Gagnon, N., Goon, J. TM., Graham, K., Guillian, E., Habib, S., Hahn, R. L., Hallin, A. L., Hallman, E. D., Harvey, P. J., Hazama, R., Heintzelman, W. J., Heise, J., Helmer, R. L., Hime, A., Howard, C., Huang, M., Jagam, P., Jamieson, B., Jelley, N. A., Jerkins, M., Keeter, K. J., Klein, J. R., Kormos, L. L., Kos, M., Kraus, C., Krauss, C. B., Krueger, A., Kutter, T., Kyba, C. C. M., Lange, R., Law, J., Lawson, I. T., Lesko, K. T., Leslie, J. R., Levine, I., Loach, J. C., MacLellan, R., Majerus, S., Mak, H. B., Maneira, J., Martin, R., McCauley, N., McDonald, A. B., McGee, S. R., Miller, M. L., Monreal, B., Monroe, J., Nickel, B. G., Noble, A. J., O'Keeffe, H. M., Oblath, N. S., Ollerhead, R. W., Gann, G. D. Orebi, Oser, S. M., Ott, R. A., Peeters, S. J. M., Poon, A. W. P., Prior, G., Reitzner, S. D., Rielage, K., Robertson, B. C., Robertson, R. G. H., Schwendener, M. H., Secrest, J. A., Seibert, S. R., Simard, O., Simpson, J. J., Sinclair, D., Skensved, P., Sonley, T. J., Stonehill, L. C., Tesic, G., Tolich, N., Tsui, T., Van Berg, R., VanDevender, B. A., Virtue, C. J., Wall, B. L., Waller, D., Tseung, H. Wan Chan, Wark, D. L., Watson, P. J. S., Wendland, J., West, N., Wilkerson, J. F., Wilson, J. R., Wouters, J. M., Wright, A., Yeh, M., Zhang, F., and Zuber, K.

Subjects
Astrophysics - Solar and Stellar Astrophysics, Nuclear Experiment
Abstract

The Sudbury Neutrino Observatory (SNO) has confirmed the standard solar model and neutrino oscillations through the observation of neutrinos from the solar core. In this paper we present a search for neutrinos associated with sources other than the solar core, such as gamma-ray bursters and solar flares. We present a new method for looking for temporal coincidences between neutrino events and astrophysical bursts of widely varying intensity. No correlations were found between neutrinos detected in SNO and such astrophysical sources.

Published
2013
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10. Measurement of the $\nu_e$ and Total $^{8}$B Solar Neutrino Fluxes with the Sudbury Neutrino Observatory Phase-III Data Set

Author

Aharmim, B., Ahmed, S. N., Amsbaugh, J. F., Anaya, J. M., Anthony, A. E., Banar, J., Barros, N., Beier, E. W., Bellerive, A., Beltran, B., Bergevin, M., Biller, S. D., Boudjemline, K., Boulay, M. G., Bowles, T. J., Browne, M. C., Bullard, T. V., Burritt, T. H., Cai, B., Chan, Y. D., Chauhan, D., Chen, M., Cleveland, B. T., Cox, G. A., Currat, C. A., Dai, X., Deng, H., Detwiler, J. A., DiMarco, M., Doe, P. J., Doucas, G., Dragowsky, M. R., Drouin, P. -L., Duba, C. A., Duncan, F. A., Dunford, M., Earle, E. D., Elliott, S. R., Evans, H. C., Ewan, G. T., Farine, J., Fergani, H., Fleurot, F., Ford, R. J., Formaggio, J. A., Fowler, M. M., Gagnon, N., Germani, J. V., Goldschmidt, A., Goon, J. TM., Graham, K., Guillian, E., Habib, S., Hahn, R. L., Hallin, A. L., Hallman, E. D., Hamian, A. A., Harper, G. C., Harvey, P. J., Hazama, R., Heeger, K. M., Heintzelman, W. J., Heise, J., Helmer, R. L., Henning, R., Hime, A., Howard, C., Howe, M. A., Huang, M., Jagam, P., Jamieson, B., Jelley, N. A., Keeter, K. J., Klein, J. R., Kormos, L. L., Kos, M., Krueger, A., Kraus, C., Krauss, C. B., Kutter, T., Kyba, C. C. M., Lange, R., Law, J., Lawson, I. T., Lesko, K. T., Leslie, J. R., Loach, J. C., MacLellan, R., Majerus, S., Mak, H. B., Maneira, J., Martin, R., McCauley, N., McDonald, A. B., McGee, S. R., Mifflin, C., Miller, G. G., Miller, M. L., Monreal, B., Monroe, J., Morissette, B., Myers, A. W., Nickel, B. G., Noble, A. J., O'Keeffe, H. M., Oblath, N. S., Ollerhead, R. W., Gann, G. D. Orebi, Oser, S. M., Ott, R. A., Peeters, S. J. M., Poon, A. W. P., Prior, G., Reitzner, S. D., Rielage, K., Robertson, B. C., Robertson, R. G. H., Rollin, E., Schwendener, M. H., Secrest, J. A., Seibert, S. R., Simard, O., Simpson, J. J., Skensved, P., Smith, M. W. E., Sonley, T. J., Steiger, T. D., Stonehill, L. C., Tesic, G., Thornewell, P. M., Tolich, N., Tsui, T., Tunnell, C. D., Van Wechel, T., Van Berg, R., VanDevender, B. A., Virtue, C. J., Wall, B. L., Waller, D., Tseung, H. Wan Chan, Wendland, J., West, N., Wilhelmy, J. B., Wilkerson, J. F., Wilson, J. R., Wouters, J. M., Wright, A., Yeh, M., Zhang, F., and Zuber, K.

Subjects
Nuclear Experiment, Astrophysics - Solar and Stellar Astrophysics, High Energy Physics - Experiment
Abstract

This paper details the solar neutrino analysis of the 385.17-day Phase-III data set acquired by the Sudbury Neutrino Observatory (SNO). An array of $^3$He proportional counters was installed in the heavy-water target to measure precisely the rate of neutrino-deuteron neutral-current interactions. This technique to determine the total active $^8$B solar neutrino flux was largely independent of the methods employed in previous phases. The total flux of active neutrinos was measured to be $5.54^{+0.33}_{-0.31}(stat.)^{+0.36}_{-0.34}(syst.)\times 10^{6}$ cm$^{-2}$ s$^{-1}$, consistent with previous measurements and standard solar models. A global analysis of solar and reactor neutrino mixing parameters yielded the best-fit values of $\Delta m^2 = 7.59^{+0.19}_{-0.21}\times 10^{-5}{eV}^2$ and $\theta = 34.4^{+1.3}_{-1.2}$ degrees., Comment: 104 pages, 26 figures, 20 tables, submitted to Phys. Rev. C

Published
2011
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11. Cyclotron effect on coherent spin precession of two-dimensional electrons

Author

Griesbeck, M., Glazov, M. M., Korn, T., Sherman, E. Ya., Waller, D., Reichl, C., Schuh, D., Wegscheider, W., and Schüller, C.

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Materials Science
Abstract

We investigate the spin dynamics of high-mobility two-dimensional electrons in GaAs/AlGaAs quantum wells grown along the $[001]$ and $[110]$ directions by time-resolved Faraday rotation at low temperatures. In measurements on the $(001)$-grown structures without external magnetic fields, we observe coherent oscillations of the electron spin polarization about the effective spin-orbit field. In non-quantizing magnetic fields applied normal to the sample plane, the cyclotron motion of the electrons rotates the effective spin-orbit field. This rotation leads to fast oscillations in the spin polarization about a non-zero value and a strong increase in the spin dephasing time in our experiments. These two effects are absent in the $(110)$-grown structure due to the different symmetry of its effective spin-orbit field. The measurements are in excellent agreement with our theoretical model., Comment: 4 pages, 3 figures

Published
2009
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19. Natural history of relapsed myeloma, refractory to immunomodulatory drugs and proteasome inhibitors: a multicenter IMWG study

Author

Kumar, S K, Dimopoulos, M A, Kastritis, E, Terpos, E, Nahi, H, Goldschmidt, H, Hillengass, J, Leleu, X, Beksac, M, Alsina, M, Oriol, A, Cavo, M, Ocio, E M, Mateos, M V, O'Donnell, E K, Vij, R, Lokhorst, H M, van de Donk, N W C J, Min, C, Mark, T, Turesson, I, Hansson, M, Ludwig, H, Jagannath, S, Delforge, M, Kyriakou, C, Hari, P, Mellqvist, U, Usmani, S Z, Dytfeld, D, Badros, A Z, Moreau, P, Kim, K, Otero, P R, Lee, J H, Shustik, C, Waller, D, Chng, W J, Ozaki, S, Lee, J-J, de la Rubia, J, Eom, H S, Rosinol, L, Lahuerta, J J, Sureda, A, Kim, J S, and Durie, B G M

Published
2017
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20. Crystallization and preliminary X‐ray analysis of human endothelin

Author

Waller, D, Cudney, R, Wolff, M, Day, J, Greenwood, A, Larson, S, and McPherson, A

Subjects
Crystallization, Endothelins, Humans, Protein Conformation, X-Ray Diffraction, Analytical Chemistry, Physical Chemistry (incl. Structural), Materials Engineering, Inorganic & Nuclear Chemistry
Abstract

Endothelin, a potent regulator of vasoconstriction and hypertension, is a naturally produced peptide of 21 amino acids containing two disulfide bonds. We have crystallized endothelin from humans using the vapor-diffusion technique, characterized the crystals by X-ray diffraction analysis, and have collected the X-ray intensities to a resolution of 1.8 A. The crystals, which demonstrate physical properties similar to most protein crystals and have a comparable solvent content, are hexagonal prisms that frequently grow to lengths of 400 microns and widths of 150 microns. The space group of the crystals is P6(1)22 (or P6(5)22), with a = 27.4, c = 79.6 A. There is one molecule of endothelin in the asymmetric unit of the crystals.

Published
1992

22. Lung volume reduction surgeryversusendobronchial valves: a randomised controlled trial

Author

Buttery, SC, Banya, W, Bilancia, R, Boyd, E, Buckley, J, Greening, NJ, Housley, K, Jordan, S, Kemp, SV, Kirk, AJB, Latimer, L, Lau, K, Lawson, R, Lewis, A, Moxham, J, Rathinam, S, Steiner, MC, Tenconi, S, Waller, D, Shah, PL, Hopkinson, NS, CELEB investigators, and CELEB investigators

Subjects
surgery, Pulmonary and Respiratory Medicine, emphysema, lung volume reduction, COPD, endobronchial valve
Abstract

BackgroundLung volume reduction surgery (LVRS) and bronchoscopic lung volume reduction (BLVR) with endobronchial valves can improve outcomes in appropriately selected patients with emphysema. However, no direct comparison data exist to inform clinical decision making in people who appear suitable for both procedures. Our aim was to investigate whether LVRS produces superior health outcomes when compared with BLVR at 12 months.MethodsThis multicentre, single-blind, parallel-group trial randomised patients from five UK hospitals, who were suitable for a targeted lung volume reduction procedure, to either LVRS or BLVR and compared outcomes at 1 year using the i-BODE score. This composite disease severity measure includes body mass index, airflow obstruction, dyspnoea and exercise capacity (incremental shuttle walk test). The researchers responsible for collecting outcomes were masked to treatment allocation. All outcomes were assessed in the intention-to-treat population.Results88 participants (48% female, mean±sdage 64.6±7.7 years, forced expiratory volume in 1 s percent predicted 31.0±7.9%) were recruited at five specialist centres across the UK and randomised to either LVRS (n=41) or BLVR (n=47). At 12 months follow-up, the complete i-BODE was available in 49 participants (21 LVRS/28 BLVR). Neither improvement in the i-BODE score (LVRS −1.10±1.44versusBLVR −0.82±1.61; p=0.54) nor in its individual components differed between groups. Both treatments produced similar improvements in gas trapping (residual volume percent predicted: LVRS −36.1% (95% CI −54.6– −10%)versusBLVR −30.1% (95% CI −53.7– −9%); p=0.81). There was one death in each treatment arm.ConclusionOur findings do not support the hypothesis that LVRS is a substantially superior treatment to BLVR in individuals who are suitable for both treatments.

Published
2023

40. Measurement of neutron production in atmospheric neutrino interactions at the Sudbury Neutrino Observatory

Author

SNO Collaboration, Aharmim, B., Ahmed, S. N., Anthony, A. E., Barros, N., Beier, E. W., Bellerive, A., Beltran, B., Bergevin, M., Biller, S. D., Bonventre, R., Boudjemline, K., Boulay, M. G., Cai, B., Callaghan, E. J., Caravaca, J., Chan, Y. D., Chauhan, D., Chen, M., Cleveland, B. T., Cox, G. A., Dai, X., Deng, H., Descamps, F. B., Detwiler, J. A., Doe, P. J., Doucas, G., Drouin, P. -L., Dunford, M., Elliott, S. R., Evans, H. C., Ewan, G. T., Farine, J., Fergani, H., Fleurot, F., Ford, R. J., Formaggio, J. A., Gagnon, N., Gilje, K., Goon, J. TM., Graham, K., Guillian, E., Habib, S., Hahn, R. L., Hallin, A. L., Hallman, E. D., Harvey, P. J., Hazama, R., Heintzelman, W. J., Heise, J., Helmer, R. L., Hime, A., Howard, C., Huang, M., Jagam, P., Jamieson, B., Jelley, N. A., Jerkins, M., Keeter, K. J., Klein, J. R., Kormos, L. L., Kos, M., Kruger, A., Kraus, C., Krauss, C. B., Kutter, T., Kyba, C. C. M., Land, B. J., Lange, R., Law, J., Lawson, I. T., Lesko, K. T., Leslie, J. R., Levine, I., Loach, J. C., MacLellan, R., Majerus, S., Mak, H. B., Maneira, J., Martin, R. D., Mastbaum, A., McCauley, N., McDonald, A. B., McGee, S. R., Miller, M. L., Monreal, B., Monroe, J., Nickel, B. G., Noble, A. J., O'Keeffe, H. M., Oblath, N. S., Okada, C. E., Ollerhead, R. W., Gann, G. D. Orebi, Oser, S. M., Ott, R. A., Peeters, S. J. M., Poon, A. W. P., Prior, G., Reitzner, S. D., Rielage, K., Robertson, B. C., Robertson, R. G. H., Schwendener, M. H., Secrest, J. A., Seibert, S. R., Simard, O., Sinclair, D., Singh, J., Skensved, P., Smiley, M., Sonley, T. J., Stonehill, L. C., Tesic, G., Tolich, N., Tsui, T., Van Berg, R., VanDevender, B. A., Virtue, C. J., Wall, B. L., Waller, D., Tseung, H. Wan Chan, Wark, D. L., Wendland, J., West, N., Wilkerson, J. F., Wilson, J. R., Winchester, T., Wright, A., Yeh, M., Zhang, F., and Zuber, K.

Subjects
Heavy water, Physics, Sudbury Neutrino Observatory, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, High Energy Physics::Phenomenology, FOS: Physical sciences, 01 natural sciences, Visible energy, High Energy Physics - Experiment, Nuclear physics, chemistry.chemical_compound, High Energy Physics - Experiment (hep-ex), chemistry, 0103 physical sciences, High Energy Physics::Experiment, ddc:530, Neutron, Production (computer science), Atmospheric neutrino, Neutrino, 010306 general physics, Nuclear Experiment, QC
Abstract

Author(s): Aharmim, B; Ahmed, SN; Anthony, AE; Barros, N; Beier, EW; Bellerive, A; Beltran, B; Bergevin, M; Biller, SD; Bonventre, R; Boudjemline, K; Boulay, MG; Cai, B; Callaghan, EJ; Caravaca, J; Chan, YD; Chauhan, D; Chen, M; Cleveland, BT; Cox, GA; Dai, X; Deng, H; Descamps, FB; Detwiler, JA; Doe, PJ; Doucas, G; Drouin, P-L; Dunford, M; Elliott, SR; Evans, HC; Ewan, GT; Farine, J; Fergani, H; Fleurot, F; Ford, RJ; Formaggio, JA; Gagnon, N; Gilje, K; Goon, JTM; Graham, K; Guillian, E; Habib, S; Hahn, RL; Hallin, AL; Hallman, ED; Harvey, PJ; Hazama, R; Heintzelman, WJ; Heise, J; Helmer, RL; Hime, A; Howard, C; Huang, M; Jagam, P; Jamieson, B; Jelley, NA; Jerkins, M; Keeter, KJ; Klein, JR; Kormos, LL; Kos, M; Kruger, A; Kraus, C; Krauss, CB; Kutter, T; Kyba, CCM; Land, BJ; Lange, R; Law, J; Lawson, IT; Lesko, KT; Leslie, JR; Levine, I; Loach, JC; MacLellan, R; Majerus, S; Mak, HB; Maneira, J; Martin, RD; Mastbaum, A; McCauley, N; McDonald, AB; McGee, SR; Miller, ML; Monreal, B | Abstract: Neutron production in GeV-scale neutrino interactions is a poorly studied process. We have measured the neutron multiplicities in atmospheric neutrino interactions in the Sudbury Neutrino Observatory experiment and compared them to the prediction of a Monte Carlo simulation using GENIE and a minimally modified version of GEANT4. We analyzed 837 days of exposure corresponding to Phase I, using pure heavy water, and Phase II, using a mixture of Cl in heavy water. Neutrons produced in atmospheric neutrino interactions were identified with an efficiency of $15.3\%$ and $44.3\%$, for Phase I and II respectively. The neutron production is measured as a function of the visible energy of the neutrino interaction and, for charged current quasi-elastic interaction candidates, also as a function of the neutrino energy. This study is also performed classifying the complete sample into two pairs of event categories: charged current quasi-elastic and non charged current quasi-elastic, and $\nu_{\mu}$ and $\nu_e$. Results show good overall agreement between data and Monte Carlo for both phases, with some small tension with a statistical significance below $2\sigma$ for some intermediate energies.

Published
2020

43. Cosmogenic neutron production at the Sudbury Neutrino Observatory

Author

SNO Collaboration, Aharmim, B., Ahmed, S. N., Anthony, A. E., Barros, N., Beier, E. W., Bellerive, A., Beltran, B., Bergevin, M., Biller, S. D., Bonventre, R., Boudjemline, K., Boulay, M. G., Cai, B., Callaghan, E. J., Caravaca, J., Chan, Y. D., Chauhan, D., Chen, M., Cleveland, B. T., Cox, G. A., Curley, R., Dai, X., Deng, H., Descamps, F. B., Detwiler, J. A., Doe, P. J., Doucas, G., Drouin, P.-L., Dunford, M., Elliott, S. R., Evans, H. C., Ewan, G. T., Farine, J., Fergani, H., Fleurot, F., Ford, R. J., Formaggio, J. A., Gagnon, N., Gilje, K., Goon, J. T. M., Graham, K., Guillian, E., Habib, S., Hahn, R. L., Hallin, A. L., Hallman, E. D., Harvey, P. J., Hazama, R., Heintzelman, W. J., Heise, J., Helmer, R. L., Hime, A., Howard, C., Huang, M., Jagam, P., Jamieson, B., Jelley, N. A., Jerkins, M., Kéfélian, C., Keeter, K. J., Klein, J. R., Kormos, L. L., Kos, M., Krüger, A., Kraus, C., Krauss, C. B., Kutter, T., Kyba, C. C. M., Land, B. J., Lange, R., Law, J., Lawson, I. T., Lesko, K. T., Leslie, J. R., Levine, I., Loach, J. C., MacLellan, R., Majerus, S., Mak, H. B., Maneira, J., Martin, R. D., Mastbaum, A., McCauley, N., McDonald, A. B., McGee, S. R., Miller, M. L., Monreal, B., Monroe, J., Nickel, B. G., Noble, A. J., O’Keeffe, H. M., Oblath, N. S., Okada, C. E., Ollerhead, R. W., Orebi Gann, G. D., Oser, S. M., Ott, R. A., Peeters, S. J. M., Poon, A. W. P., Prior, G., Reitzner, S. D., Rielage, K., Robertson, B. C., Robertson, R. G. H., Schwendener, M. H., Secrest, J. A., Seibert, S. R., Simard, O., Sinclair, D., Skensved, P., Sonley, T. J., Stonehill, L. C., Tešić, G., Tolich, N., Tsui, T., Van Berg, R., VanDevender, B. A., Virtue, C. J., Wall, B. L., Waller, D., Wan Chan Tseung, H., Wark, D. L., Wendland, J., West, N., Wilkerson, J. F., Wilson, J. R., Winchester, T., Wright, A., Yeh, M., Zhang, F., and Zuber, K.

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Extrapolation, FOS: Physical sciences, 01 natural sciences, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), chemistry.chemical_compound, Neutron yield, Observatory, 0103 physical sciences, ddc:530, Neutron, Nuclear Experiment (nucl-ex), Nuclear Experiment, 010306 general physics, QC, Heavy water, Physics, Sudbury Neutrino Observatory, Muon, 010308 nuclear & particles physics, Observable, chemistry, High Energy Physics::Experiment
Abstract

Neutrons produced in nuclear interactions initiated by cosmic-ray muons present an irreducible background to many rare-event searches, even in detectors located deep underground. Models for the production of these neutrons have been tested against previous experimental data, but the extrapolation to deeper sites is not well understood. Here we report results from an analysis of cosmogenically produced neutrons at the Sudbury Neutrino Observatory. A specific set of observables are presented, which can be used to benchmark the validity of geant4 physics models. In addition, the cosmogenic neutron yield, in units of 10−4 cm2/(g·μ), is measured to be 7.28±0.09(stat)−1.12+1.59(syst) in pure heavy water and 7.30±0.07(stat)−1.02+1.40(syst) in NaCl-loaded heavy water. These results provide unique insights into this potential background source for experiments at SNOLAB.

Published
2019

44. Evidence-based reproductive health care in Cameroon: population-based study of awareness, use and barriers

Author

Tita, Alan T.N., Selwyn, Beatrice J., Waller, D. Kim, Kapadia, Asha S., and Dongmo, Sylvestre

Subjects
Reproductive organs -- Care and treatment, Medical care -- Services
Abstract

Objective To estimate the prevalence of awareness and use of evidence-based reproductive health interventions and to describe the barriers associated with the use of evidence-based interventions among health providers in north-west Cameroon. Methods In February 2004, a population-based descriptive study of the awareness and use of 13 evidence-based interventions targeted health workers providing reproductive health care. Their awareness and use of a composite of four vital interventions was also evaluated. These were peripartum use of antiretrovirals to prevent transmission of HIV, antenatal corticosteroid administration, magnesium sulfate prophylaxis and active management of placental delivery with uterotonics, tn-depth interviews with key informants were conducted as part of a qualitative substudy to discover the barriers to the use of evidence-based interventions. Findings Overall, 91.4% (328/359) of reproductive health workers were surveyed. Their awareness of evidence-based interventions varied from 29% for the use of antenatal corticosteroids to 97% for the use of iron and folic acid supplementation during pregnancy. Their use of these interventions ranged from 10.2% for antenatal corticosteroids to 94.8% for iron and folic acid supplementation. Only 50/322 (15.5%; 95% confidence interval (Cl) = 11.8-20.0) of health workers were aware of all four vital interventions, and only 12/312 (3.8%; 95% Cl = 2.0-6.6) reported using all of them regularly. A total of 26 key informants participated in the qualitative substudy. A deficiency in the education and training of health workers, especially a lack of continuing education, was commonly identified as the most important barrier to their awareness of evidence-based practices. A lack of awareness and a lack of supplies and materials were the main barriers to practice. Conclusion The awareness and practice of important evidence-based reproductive health interventions were less than optimal. To improve maternal and perinatal outcomes both remedial programmes to enhance awareness, including continuing education for health workers, and the provision of necessary supplies are needed. Keywords Reproductive health services; Evidence-based medicine; Health personnel/education; Health knowledge, attitudes, practice; Pregnancy complications/drug therapy;Adrenal cortex hormones/therapeutic use;Anti-retroviral agents/therapeutic use; Magnesium sulfate/therapeutic use; Tocolytic agents/therapeutic use; Population surveillance; Cameroon (source: MeSH, NLM). Soins de sante genesique fondes sur l&apos;experience au Cameroun : etudes en population de la connaissance et de la mise en oeuvre de ces soins, ainsi que des obstacle rencontres dans cette mise en oeuvre Objectif Estimer la frequence de la connaissance et de l&apos;utilisation d&apos;interventions de sante genesique reposant sur l&apos;experience et decrire les obstacles s&apos;opposant a la mise en oeuvre de ces interventions par les soignants au nord-ouest du Cameroun. Methodes En fevrier 2004, une etude descriptive en population de la connaissance et de l&apos;utilisation de 13 interventions reposant sur l&apos;experience a ete menee chez des agents de sante dispensant des soins de sante genesique. On a egalement evalue la connaissance et l&apos;utilisation d&apos;un ensemble de quatre interventions vitales a savoir, l&apos;utilisation pendant le peripartum d&apos;antiretroviraux pour prevenir la transmission du VIH, l&apos;administration prenatale de corticosteroides, la prophylaxie par le sulfate de magnesium et la prise en charge active de la delivrance placentaire au moyen d&apos;uterotoniques. Des entretiens approfondis avec des informateurs cles se sont deroules dans le cadre d&apos;une etude subsidiaire qualitative, visant a determiner les obstacles a l&apos;utilisation d&apos;interventions reposant sur l&apos;experience. Resultats Au total, 91,4 % (328/359) des soignants en sante genesique ont participe a l&apos;enquete. Leur connaissance des interventions reposant sur l&apos;experience se situait entre 29% pour l&apos;utilisation prenatale de corticosteroides et 97% pour l&apos;utilisation de la supplementation en fer et en acide folique au cours de la grossesse. La mise en oeuvre de ces interventions se situait entre 10,2 % pour l&apos;administration prenatale de corticosteroides et 94,8 % pour la supplementation en fer et en acide folique. Seuls 50 agents de sante sur 322 (15,5%; intervalle de confiance [IC a 95% = 11,8-20,0) connaissaient les quatre interventions vitales et seuls 12/312 (3,8% ; IC 95% = 2,0-6,6) ont indique qu&apos;ils les utilisaient tous regulierement. Au total 26 informateurs cles ont participe a l&apos;etude subsidiaire qualitative. Des lacunes au niveau de l&apos;education et de la formation des agents de sante, notamment l&apos;absence d&apos;une formation continue, ont ete frequemment identifiees comme l&apos;obstacle le plus important a la connaissance des pratiques reposant sur l&apos;experience. Les connaissances insuffisantes et le manque de fournitures et de materiel etaient les principaux obstacles a leur mise en oeuvre. Conclusion La connaissance et la mise en oeuvre d&apos;interventions importantes en sante genesique et reposant sur l&apos;experience n&apos;etaient pas optimales. Pour ameliorer les resultats obtenus au niveau maternel et perinatal, il faut a la fois offrir des programmes pour renforcer les connaissances des agents de sante, notamment une formation continue, et apporter les fournitures necessaires. Mots cles Services de medecine de la reproduction; Personnel sanitaire/enseignement; Medecine factuelle; Connaissance, attitude, pratique; Grossesse compliquee/chimiotherapie; Hormones corticosurrenaliennes/usage therapeutique; Agents antiretroviraux/usage therapeutique; Sulfate magnesium/usage therapeutique; Agents tocolytiques/usage therapeutique; Surveillance population; Cameroun (source: MeSH, INSERM). Atencion de salud reproductiva basada en la evidencia en el Camerun: estudio poblacional sobre los conocimientos, la aplicacion y las barreras. Objetivo Estimar la prevalencia de los conocimientos y la aplicacion de las intervenciones de salud reproductiva basadas en la evidencia, y describir las barreras que se oponen al uso de esas intervenciones entre los proveedores de asistencia sanitaria en el noroeste del Camerun. Metodos En febrero de 2004 se realizo un estudio descriptivo poblacional sobre el conocimiento y uso de 13 intervenciones basadas en la evidencia, centrado en personal sanitario que dispensaba atencion de salud reproductiva. Se evaluaron tambien sus conocimientos y aplicacion de un conjunto de cuatro intervenciones fundamentales: el uso de antirretrovirales durante el parto para prevenir la transmision del VIH, la administracion prenatal de cortiocosteroides, la profilaxis con sulfato de magnesio y el fomento activo de la expulsion de la placenta con uterotonicos. Ademas, se llevaron a cabo entrevistas detalladas con informantes clave como parte de un subestudio cualitativo destinado a identificar las barreras a la aplicacion de esas intervenciones basadas en la evidencia. Resultados Se estudio en total al 91,4% (328/359) de los trabajadores de salud reproductiva. Su conocimiento de las intervenciones basadas en la evidencia variaba entre el 29% para la utilizacion prenatal de corticosteroides y el 97% para la administracion de suplementos de hierro y acido folico durante el embarazo. Su utilizacion de esas intervenciones variaba desde el 10,2% en el caso de los corticosteroides prenatales hasta el 94,8% en el caso de los suplementos de hierro y acido folico. Solo 50 de 322 (15,5%; intervalo de confianza [IC] del 95% = 11,8-20,0) trabajadores sanitarios conocian las cuatro intervenciones esenciales analizadas, y solo 12 de 312 (3,8%; IC95% = 2,0-6,6) senalaron que aplicaban todas ellas regularmente. Un total de 26 informantes clave participaron en el subestudio cualitativo. La barrera mas importante en cuanto al conocimiento de las practicas basadas en la evidencia resulto ser una deficiente formacion teorica y practica del personal sanitario, especialmente la falta de ensenanza continua. La falta de conocimientos y la falta de suministros y material eran las barreras principales a la aplicacion de esas practicas. Conclusion El conocimiento y la aplicacion de importantes intervenciones de salud reproductiva basadas en la evidencia eran suboptimos. Para mejorar los resultados matemos y perinatales se necesitan tanto programas correctivos que aumenten los conocimientos, en particular ensenanza continua para los agentes de salud, como suministros suficientes. Palabras clave Servicios de salud reproductiva; Personal de salud/educacion; Medicina basada en evidencia; Conocimientos, actitudes y practica sanitarias; Complicaciones del embarazo/quimioterapia; Corticosteroides/uso terapeutico; Agentes antirretrovirales/uso terapeutico; Sulfato de magnesio/uso terapeutico; Agentes tocoliticos/uso terapeutico; Vigilancia de la poblacion; Camerun (fuente: DeCS, BIREME). [TEXT NOT REPRODUCIBLE IN ASCII.], Introduction More than 500 000 women die annually from pregnancy-related complications and millions become ill from these complications (1). Altogether, 99% of these deaths occur in the developing world, especially [...]

Published
2005

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