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1. First measurement using elliptically polarized photons of the double-polarization observable $E$ for $\gamma p \to p \pi^0$ and $\gamma p \to n \pi^+$

Author

A2 Collaboration, Afzal, F., Spieker, K., Hurck, P., Abt, S., Achenbach, P., Adlarson, P., Ahmed, Z., Akondi, C. S., Annand, J. R. M., Arends, H. J., Bashkanov, M., Beck, R., Biroth, M., Borisov, N., Braghieri, A., Briscoe, W. J., Cividini, F., Collicott, C., Costanza, S., Denig, A., Dieterle, M., Downie, E. J., Drexler, P., Fegan, S., Gardner, S., Ghosal, D., Glazier, D. I., Gorodnov, I., Gradl, W., Gurevich, D., Heijkenskjöld, L., Hornidge, D., Huber, G. M., Kashevarov, V. L., Kay, S. J. D., Korolija, M., Krusche, B., Lazarev, A., Livingston, K., Lutterer, S., MacGregor, I. J. D., Macrae, R. G., Manley, D. M., Martel, P. P., Miskimen, R., Mocanu, M., Mornacchi, E., Mullen, C., Neganov, A., Neiser, A., Oberle, M., Ostrick, M., Otte, P. B., Paudyal, D., Pedroni, P., Powell, A., Reicherz, G., Rostomyan, T., Sfienti, C., Sokhoyan, V., Steffen, O., Strakovsky, I. I., Strub, T., Supek, I., Thiel, A., Thiel, M., Thomas, A., Usov, Yu. A., Wagner, S., Walford, N. K., Watts, D. P., Werthmüller, D., Wettig, J., Witthauer, L., Wolfes, M., and Zachariou, N.

Subjects
Nuclear Experiment
Abstract

We report the measurement of the helicity asymmetry $E$ for the $p\pi^0$ and $n\pi^+$ final states using, for the first time, an elliptically polarized photon beam in combination with a longitudinally polarized target at the Crystal Ball experiment at MAMI. The results agree very well with data that were taken with a circularly polarized photon beam, showing that it is possible to simultaneously measure polarization observables that require linearly (e.g.~$G$) and circularly polarized photons (e.g.~$E$) and a longitudinally polarized target. The new data cover a photon energy range 270 - 1400 MeV for the $p\pi^0$ final state (230 - 842 MeV for the $n\pi^+$ final state) and the full range of pion polar angles, $\theta$, providing the most precise measurement of the observable $E$. A moment analysis gives a clear observation of the $p\eta$ cusp in the $p\pi^0$ final state.

Published
2024

2. Re-evaluation of the Mesozoic-Cenozoic biostratigraphy of the Laurentian Subbasin of the Scotian Basin, offshore eastern Canada

Author

Weston, Janice F., Macrae, R. Andrew, Ascoli, Piero, Cooper, M. Kevin E., Fensome, Robert A., Shaw, David, and Williams, Graham L.

Subjects
Cambridge University Press, Mass extinction theory -- Analysis, Relative dating (Chronology) -- Analysis, Book publishing -- Analysis, Earth sciences
Abstract

We use new and existing nannofossil, palynological, and microfossil biostratigraphic data in conjunction with lithologic and geophysical logs from four wells to establish a series of sequence-stratigraphic events in the Mesozoic-Cenozoic of the Laurentian Subbasin of offshore Newfoundland, eastern Canada. Well biostratigraphic events are integrated with reflection seismic in the area to correlate regional seismic stratigraphic surfaces. The four wells are: Bandol-1, Emerillon C-56, East Wolverine G-37, and Heron H-73. We extend the event stratigraphic scheme previously developed for the Scotian Margin, offshore Nova Scotia, into new areas to the east along the southern Grand Banks, where we recognize four new well-log sequence stratigraphic events, and we modify the definition of a previously recognized regional surface. The new and modified regional surfaces are the Early Albian Unconformity, the Late Bathonian Maximum Flooding Surface (MFS), the Late Bajocian MFS (renamed from Bathonian/Bajocian MFS), the ?Bajocian/Toarcian Unconformity, and the Late Pliensbachian MFS. We recognize the 'Avalon Unconformity' and 'Base-Tertiary Unconformity' of previous studies as amalgamations of multiple smaller-scale unconformities and refine their age in the studied wells. A major improvement over our earlier Scotian Margin event schemes is the extension of the event stratigraphy into the Early Jurassic using a suite of marine biostratigraphic markers. We compare the Early Jurassic event scheme to Deep Sea Drilling Project Site 547B on the conjugate Moroccan Margin to better constrain potential source rock intervals and the early history of the central Atlantic Ocean. Nous utilisons des donn es biostratigraphiques sur les microfossiles, des donn es palynologiques et des donn es sur les nanofossiles, nouvelles et existantes, conjointement avec des diagraphies lithologiques et g ophysiques de quatre puits pour d finir une s rie de ph nom nes stratigraphiques s quentiels de la tranche du M sozo que-C nozo que du sous-bassin Laurentien au large des c tes de Terre-Neuve, dans l'est du Canada. Les ph nom nes biostratigraphiques des puits sont int gr s la sismique r flexion dans le secteur aux fins d'une corr lation des surfaces stratigraphiques sismiques r gionales. Les quatre puits en question sont les puits Bandol-1, Emerillon C-56, East Wolverine G-37 et Heron H-73. Nous largissons le plan stratigraphique des ph nom nes pr c demment cr pour la marge de Scotian, au large des c tes de la Nouvelle- cosse, aux nouveaux secteurs l'est le long de la zone m ridionale des Grands bancs, o nous reconnaissons quatre nouveaux ph nom nes stratigraphiques s quentiels dans les diagraphies des puits et nous modifions la d finition d'une surface r gionale ant rieurement reconnue. Les nouvelles surfaces r gionales modifi es sont la discordance de l'Albien pr coce, la surface d'inondation maximale (SIM) du Bathonien tardif, la SIM du Bajocien tardif (SIM du Bathonien/Bajocien rebaptis e), la discordance bajocienne?/toarcienne et la SIM du Pliensbachien tardif. Nous reconnaissons la << discordance d'Avalon >> et la << discordance de base-tertiaire >> d' tudes ant rieures en tant que regroupements de plusieurs discordances d' chelle plus modeste et nous d terminons leur ge de fa on plus pr cise dans les puits tudi s. Une am lioration notable par rapport nos plans ant rieurs des ph nom nes survenus dans la marge de Scotian est l' largissement de la stratigraphie des ph nom nes au cours du Jurassique pr coce au moyen de rep res stratigraphiques marins. Nous comparons le plan des ph nom nes du Jurassique pr coce au site 547B du projet de forage en eau profonde sur la marge marocaine conjugu e pour mieux limiter les intervalles ventuels de roche m re et les d buts de l'oc an Atlantique central., INTRODUCTION The Scotian Margin Play Fairway Analysis (PFA) project was a multidisciplinary study (under the auspices of the Offshore Energy Technology Research Association of Nova Scotia; OERA 2011) that examined [...]

Published
2023
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3. Spin polarizabilities of the proton by measurement of Compton double-polarization observables

Author

Paudyal, D., Martel, P. P., Huber, G. M., Hornidge, D., Abt, S., Achenbach, P., Adlarson, P., Afzal, F., Ahmed, Z., Akondi, C. S., Annand, J. R. M., Arends, H. J., Bashkanov, M., Beck, R., Biroth, M., Borisov, N. S., Braghieri, A., Briscoe, W. J., Cividini, F., Costanza, S., Collicott, C., Denig, A., Dieterle, M., Downie, E. J., Drexler, P., Ferretti-Bondy, M. I., Gardner, S., Garni, S., Glazier, D. I., Glowa, D., Gorodnov, I., Gradl, W., Günther, S., Gurevich, G. M., Hamilton, D., Heijkenskjöld, L., Käser, A., Kashevarov, V. L., Kay, S., Keshelashvili, I., Kondratiev, R., Korolija, M., Krusche, B., Lazarev, A. B., Linturi, J. M., Lisin, V., Livingston, K., Lutterer, S., MacGregor, I. J. D., Macrae, R., Mancell, J., Manley, D. M., Metag, V., Meyer, W., Miskimen, R., Mornacchi, E., Mullen, C., Mushkarenkov, A., Neganov, A. B., Neiser, A., Oberle, M., Ostrick, M., Otte, P. B., Pedroni, P., Polonski, A., Powell, A., Prakhov, S. N., Rajabi, A., Reicherz, G., Ron, G., Rostomyan, T., Sarty, A., Sfienti, C., Sikora, M. H., Sokhoyan, V., Spieker, K., Steffen, O., Strakovsky, I. I., Strub, Th., Supek, I., Thiel, A., Thiel, M., Thomas, A., Unverzagt, M., Usov, Yu. A., Wagner, S., Walford, N. K., Watts, D. P., Werthmüller, D., Wettig, J., Witthauer, L., Wolfes, M., and Zana, L.

Subjects
Nuclear Experiment
Abstract

The Compton double-polarization observable $\Sigma_{2z}$ has been measured for the first time in the $\Delta(1232)$ resonance region using a circularly polarized photon beam incident on a longitudinally polarized target at the Mainz Microtron. This paper reports these results, together with the model-dependent extraction of four proton spin polarizabilities from fits to additional asymmetry data using dispersion relation and chiral perturbation theory calculations, with the former resulting in: $\gamma_{E1E1} = -3.18 \pm 0.52$, $\gamma_{M1M1} = 2.98 \pm 0.43$, $\gamma_{E1M2} = -0.44 \pm 0.67$ and $\gamma_{M1E2} = 1.58 \pm 0.43$, in units of $10^{-4}~\mathrm{fm}^{4}$., Comment: 7 pages, 5 figures, 2 tables, accepted for publication in PRC

Published
2019
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4. Cross Section for $\gamma n \to \pi^0 n$ measured at Mainz/A2

Author

Briscoe, W. J., Hadzimehmedovi, M., Kudryavtsev, A. E., Kulikov, V. V., Martemianov, M. A., Strakovsky, I. I., Svarc, A., Tarasov, V. E., Workman, R. L., Abt, S., Achenbach, P., Akondi, C. S., Afzal, F., Aguar-Bartolome, P., Ahmed, Z., Annand, J. R. M., Arends, H. J., Bantawa, K., Bashkanov, M., Beck, R., Biroth, M., Borisov, N., Braghieri, A., Bulychjov, S. A., Cividini, F., Collicott, C., Costanza, S., Denig, A., Downie, E. J., Drexler, P., Fegan, S., Bondy, M. I. Ferretti, Gardner, S., Ghosal, D., Glazier, D. I., Gorodnov, I., Gradl, W., Gunther, M., Gurevich, D., Heijkenskjold, L., Hornidge, D., Huber, G. M., Kaeser, M., Kashevarov, V. L., Kay, S., Korolija, M., Krusche, B., Lazarev, A., Livingston, K., Lutterer, S., MacGregor, I. J. D., Macrae, R., Manley, D. M., Martel, P. P., McGeorge, J. C., Middleton, D. G., Miskimen, R., Mornacchi, E., Mushkarenkov, A., Mullen, C., Neganov, A., Neiser, A., Ostrick, M., Otte, P. B., Osmanovic, H., Oussena, R. Omerovic B., Paudyal, D., Pedroni, P., Powell, A., Prakhov, S. N., Ron, G., Rostomyan, T., Sarty, A., Senti, C., Sokhoyan, V., Spieker, K., Stahov, J., Steffen, O., Supek, I., Thiel, A., Thiel, M., Thomas, A., Tiator, L., Unverzagt, M., Usov, Yu. A., Walford, N. K., Watts, D. P., Wagner, S., Werthmueller, D., Wettig, J., Wolfes, M., and Zachariou, N.

Subjects
Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract

The $\gamma n \to \pi^0 n$ differential cross section evaluated for 27 energy bins span the photon-energy range 290-813 MeV (W = 1.195-1.553 GeV) and the pion c.m. polar production angles, ranging from 18 deg to 162 deg, making use of model-dependent nuclear corrections to extract pi0 production data on the neutron from measurements on the deuteron target. Additionally, the total photoabsorption cross section was measured. The tagged photon beam produced by the 883-MeV electron beam of the Mainz Microtron MAMI was used for the 0-meson production. Our accumulation of 3.6 x 10^6 $\gamma n \to \pi^0 n$ events allowed a detailed study of the reaction dynamics. Our data are in reasonable agreement with previous A2 measurements and extend them to lower energies. The data are compared to predictions of previous SAID, MAID, and BnGa partial-wave analyses and to the latest SAID fit MA19 that included our data. Selected photon decay amplitudes $N^* \to \gamma n$ at the resonance poles are determined for the first time., Comment: 16 pages, 12 figures, 3 tables

Published
2019
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5. Measurement of the beam-helicity asymmetry in photoproduction of $\pi^{0}\eta$ pairs on carbon, aluminum, and lead

Author

Sokhoyan, V., Prakhov, S., Fix, A., Abt, S., Achenbach, P., Adlarson, P., Afzal, F., Aguar-Bartolomé, P., Ahmed, Z., Altangerel, K., Annand, J. R. M., Arends, H. J., Bantawa, K., Bashkanov, M., Beck, R., Biroth, M., Borisov, N. S., Braghieri, A., Briscoe, W. J., Cherepnya, S., Cividini, F., Collicott, C., Costanza, S., Denig, A., Dieterle, M., Downie, E. J., Drexler, P., Bondy, M. I. Ferretti, Fil'kov, L. V., Gardner, S., Garni, S., Glazier, D. I., Gorodnov, I., Gradl, W., Günther, M., Gurevich, G. M., Heijkenskjöld, L., Hornidge, D., Huber, G. M., Käser, A., Kashevarov, V. L., Kay, S., Keshelashvili, I., Kondratiev, R., Korolija, M., Krusche, B., Lazarev, A., Livingston, K., Lutterer, S., MacGregor, I. J. D., Macrae, R., Manley, D. M., Martel, P. P., McGeorge, J. C., Middleton, D. G., Miskimen, R., Mornacchi, E., Mullen, C., Mushkarenkov, A., Neganov, A., Neiser, A., Oberle, M., Ostrick, M., Otte, P. B., Paudyal, D., Pedroni, P., Powell, A., Rickert, E., Ron, G., Rostomyan, T., Sarty, A., Sfienti, C., Spieker, K., Steffen, O., Strakovsky, I. I., Strandberg, B., Strub, Th., Supek, I., Thiel, A., Thiel, M., Thomas, A., Unverzagt, M., Usov, Yu. A., Wagner, S., Walford, N. K., Watts, D. P., Werthmüller, D., Wettig, J., Witthauer, L., Wolfes, M., and Zachariou, N.

Subjects
Nuclear Experiment
Abstract

The beam-helicity asymmetry was measured, for the first time, in photoproduction of $\pi^{0}\eta$ pairs on carbon, aluminum, and lead, with the A2 experimental setup at MAMI. The results are compared to an earlier measurement on a free proton and to the corresponding theoretical calculations. The Mainz model is used to predict the beam-helicity asymmetry for the nuclear targets. The present results indicate that the photoproduction mechanism for $\pi^{0}\eta$ pairs on nuclei is similar to photoproduction on a free nucleon. This process is dominated by the $D_{33}$ partial wave with the $\eta\Delta(1232)$ intermediate state., Comment: Accepted for publication in Physics Letters B (2020)

Published
2019
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6. Deuteron photodisintegration by polarized photons in the region of the $d^*(2380)$

Author

Bashkanov, M., Kay, S., Watts, D. P., Mullen, C., Abt, S., Achenbach, P., Adlarson, P., Afzal, F., Ahmed, Z., Akondi, C. S., Annand, J. R. M., Arends, H. J., Beck, R., Biroth, M., Borisov, N., Braghieri, A., Briscoe, W. J., Cividini, F., Collicott, C., Costanza, S., Denig, A., Downie, E. J., Drexler, P., Garni, S., Glazier, D. I., Gorodnov, I., Gradl, W., Günther, M., Gurevich, D., Heijkenskjöld, L., Hornidge, D., Huber, G. M., Käser, A., Kashevarov, V. L., Korolija, M., Krusche, B., Lazarev, A., Livingston, K., Lutterer, S., MacGregor, I. J. D., Macrae, R., Manley, D. M., Martel, P. P., Miskimen, R., Mornacchi, E., Neganov, A., Neiser, A., Ostrick, M., Otte, P. B., Paudyal, D., Pedroni, P., Powell, A., Prakhov, S. N., Ron, G., Rostomyan, T., Sarty, A., Sfienti, C., Sokhoyan, V., Spieker, K., Steffen, O., Strakovsky, I. I., Strub, T., Supek, I., Thiel, A., Thiel, M., Thomas, A., Usov, Yu. A., Wagner, S., Walford, N. K., Werthmüller, D., Wettig, J., Wolfes, M., and Zana, L. A.

Subjects
Nuclear Experiment
Abstract

We report the first large-acceptance measurement of the beam-spin asymmetry for deuteron photodisintegration ($\vec{\gamma} d\to pn$) in the photon energy range $400

Published
2018
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7. Study of the $\gamma p\to \pi^0\eta p$ reaction with the A2 setup at MAMI

Author

Sokhoyan, V., Prakhov, S., Fix, A., Abt, S., Achenbach, P., Adlarson, P., Afzal, F., Aguar-Bartolomé, P., Ahmed, Z., Ahrens, J., Annand, J. R. M., Arends, H. J., Bantawa, K., Bashkanov, M., Beck, R., Biroth, M., Borisov, N. S., Braghieri, A., Briscoe, W. J., Cherepnya, S., Cividini, F., Collicott, C., Costanza, S., Denig, A., Dieterle, M., Downie, E. J., Drexler, P., Bondy, M. I. Ferretti, Fil'kov, L. V., Gardner, S., Garni, S., Glazier, D. I., Glowa, D., Gorodnov, I., Gradl, W., Günther, M., Gurevich, G. M., Hamill, C. B., Heijkenskjöld, L., Hornidge, D., Huber, G. M., Jude, T. C., Käser, A., Kashevarov, V. L., Kay, S., Keshelashvili, I., Kondratiev, R., Korolija, M., Krusche, B., Lazarev, A., Linturi, J., Lisin, V., Livingston, K., Lutterer, S., MacGregor, I. J. D., Macrae, R., Manley, D. M., Martel, P. P., McGeorge, J. C., McNicoll, E. F., Middleton, D. G., Miskimen, R., Mornacchi, E., Mullen, C., Mushkarenkov, A., Neganov, A., Neiser, A., Nikolaev, A., Oberle, M., Ostrick, M., Ott, P., Otte, P. B., Paudyal, D., Pedroni, P., Polonski, A., Rajabi, A., Robinson, J., Ron, G., Rosner, G., Rostomyan, T., Sarty, A., Sfienti, C., Sikora, M. H., Spieker, K., Steffen, O., Strakovsky, I. I., Strandberg, B., Strub, Th., Supek, I., Thiel, A., Thiel, M., Thomas, A., Unverzagt, M., Usov, Yu. A., Wagner, S., Walford, N. K., Watts, D. P., Werthmüller, D., Wettig, J., Witthauer, L., Wolfes, M., and Zana, L. A.

Subjects
Nuclear Experiment
Abstract

The data available from the A2 Collaboration at MAMI were analyzed to select the $\gamma p\to \pi^0\eta p$ reaction on an event-by-event basis, which allows for partial-wave analyses of three-body final states to obtain more reliable results, compared to fits to measured distributions. These data provide the world's best statistical accuracy in the energy range from threshold to $E_{\gamma}=1.45$ GeV, allowing a finer energy binning in the measurement of all observables needed for understanding the reaction dynamics. The results obtained for the measured observables are compared to existing models, and the impact from the new data is checked by the fit with the revised Mainz model., Comment: 15 pages, 18 figures

Published
2018
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8. Study of $\eta$ and $\eta'$ photoproduction at MAMI

Author

Kashevarov, V. L., Ott, P., Prakhov, S., Adlarson, P., Afzal, F., Ahmed, Z., Akondi, C. S., Annand, J. R. M., Arends, H. J., Beck, R., Braghieri, A., Briscoe, W. J., Cividini, F., Codling, R., Collicott, C., Costanza, S., Denig, A., Downie, E. J., Dieterle, M., Bondy, M. I. Ferretti, Filkov, L. V., Fix, A., Gardner, S., Garni, S., Glazier, D. I., Glowa, D., Gradl, W., Gurevich, G., Hamilton, D. J., Hornidge, D., Howdle, D., Huber, G. M., Kaeser, A., Kay, S., Keshelashvili, I., Kondratiev, R., Korolija, M., Krusche, B., Linturi, J., Lisin, V., Livingston, K., MacGregor, I. J. D., MacRae, R., Mancell, J., Manley, D. M., Martel, P. P., McGeorge, J. C., McNicol, E., Middleton, D. G., Miskimen, R., Mornacchi, E., Mullen, C., Mushkarenkov, A., Neiser, A., Oberle, M., Ostrick, M., Otte, P. B., Oussena, B., Paudyal, D., Pedroni, P., Polyanski, V. V., Rajabi, A., Robinson, J., Rosner, G., Rostomyan, T., Sarty, A., Schott, D. M., Schumann, S., Sfienti, C., Sokhoyan, V., Spieker, K., Steffen, O., Strandberg, B., Strakovsky, I. I., Strub, Th., Supek, I., Taragin, M. F., Thiel, A., Thiel, M., Tiator, L., Thomas, A., Unverzagt, M., Wagner, S., Watts, D. P., Werthmueller, D., Wettig, J., Witthauer, L., Wolfes, M., Workman, R. L., and Zana, L.

Subjects
Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract

The reactions $\gamma p\to \eta p$ and $\gamma p\to \eta' p$ have been measured from their thresholds up to the center-of-mass energy $W=1.96$GeV with the tagged-photon facilities at the Mainz Microtron, MAMI. Differential cross sections were obtained with unprecedented accuracy, providing fine energy binning and full production-angle coverage. A strong cusp is observed in the total cross section and excitation functions for $\eta$ photoproduction at the energies in vicinity of the $\eta'$ threshold, $W=1896$MeV ($E_\gamma=1447$MeV). This behavior is explained in a revised $\eta$MAID isobar model by a significant branching of the $N(1895)1/2^-$ nucleon resonance to both, $\eta p$ and $\eta' p$, confirming the existence and constraining the properties of this poorly known state.

Published
2017
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9. Measurement of the pi^0 -> e^+e^-gamma Dalitz decay at the Mainz Microtron

Author

Adlarson, P., Afzal, F., Aguar-Bartolomé, P., Ahmed, Z., Akondi, C. S., Annand, J. R. M., Arends, H. J., Bantawa, K., Beck, R., Berghäuser, H., Biroth, M., Borisov, N. S., Braghieri, A., Briscoe, W. J., Cherepnya, S., Cividini, F., Collicott, C., Costanza, S., Denig, A., Dieterle, M., Downie, E. J., Drexler, P., Bondy, M. I. Ferretti, Fil'kov, L. V., Gardner, S., Garni, S., Glazier, D. I., Glowa, D., Gradl, W., Gurevich, G. M., Hamilton, D. J., Hornidge, D., Huber, G. M., Jude, T. C., Käser, A., Kashevarov, V. L., Kay, S., Keshelashvili, I., Kondratiev, R., Korolija, M., Krusche, B., Kulikov, V. V., Lazarev, A., Linturi, J., Lisin, V., Livingston, K., MacGregor, I. J. D., Macrae, R., Manley, D. M., Martel, P. P., Martemianov, M., McGeorge, J. C., McNicoll, E. F., Metag, V., Middleton, D. G., Miskimen, R., Mornacchi, E., Mullen, C., Mushkarenkov, A., Neganov, A., Neiser, A., Nikolaev, A., Oberle, M., Ostrick, M., Ott, P., Otte, P. B., Paudyal, D., Pedroni, P., Polonski, A., Prakhov, S., Rajabi, A., Robinson, J., Ron, G., Rosner, G., Rostomyan, T., Sfienti, C., Sikora, M. H., Sokhoyan, V., Spieker, K., Steffen, O., Strakovsky, I. I., Strandberg, B., Strub, Th., Supek, I., Thiel, A., Thiel, M., Thomas, A., Unverzagt, M., Usov, Yu. A., Wagner, S., Walford, N., Watts, D. P., Werthmüller, D., Wettig, J., Witthauer, L., Wolfes, M., and Zana, L. A.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

The Dalitz decay pi^0 -> e^+e^-gamma has been measured in the gamma p -> pi^0 p reaction with the A2 tagged-photon facility at the Mainz Microtron, MAMI. The value obtained for the slope parameter of the pi^0 electromagnetic transition form factor, a_pi = 0.030+/-0.010_tot, is in agreement with existing measurements of this decay and with recent theoretical calculations. The uncertainty obtained in the value of a_pi is lower than in previous results based on the pi^0 -> e^+e^-gamma decay., Comment: 11 pages, 7 figures, 1 table

Published
2016
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10. Determination of the scalar polarizabilities of the proton using beam asymmetry $\Sigma_{3}$ in Compton scattering

Author

Sokhoyan, V., Downie, E. J., Mornacchi, E., McGovern, J. A., Krupina, N., Afzal, F., Ahrens, J., Akondi, C. S., Annand, J. R. M., Arends, H. J., Beck, R., Braghieri, A., Briscoe, W. J., Cividini, F., Collicott, C., Costanza, S., Denig, A., Dieterle, M., Ferretti, M., Gardner, S., Garni, S., Glazier, D. I., Glowa, D., Gradl, W., Gurevich, G., Hamilton, D., Hornidge, D., Huber, G. M., Käser, A., Kashevarov, V. L., Keshelashvili, I., Kondratiev, R., Korolija, M., Krusche, B., Lensky, V., Linturi, J., Lisin, V., Livingston, K., MacGregor, I. J. D., Macrae, R., Manley, D. M., Martel, P. P., Middleton, D. G., Miskimen, R., Mushkarenkov, A., Neiser, A., Oberle, M., Spina, H. Ortega, Ostrick, M., Ott, P., Otte, P. B., Oussena, B., Paudyal, D., Pedroni, P., Polonski, A., Polyansky, V., Prakhov, S., Rajabi, A., Rostomyan, T., Sarty, A., Schumann, S., Steffen, O., Strakovsky, I. I., Strandberg, B., Strub, T., Supek, I., Thiel, M., Thomas, A., Unverzagt, M., Wagner, S., Watts, D. P., Wettig, J., Witthauer, L., Werthmüller, D., Wolfes, M., and Zana, L.

Subjects
Nuclear Experiment
Abstract

The scalar dipole polarizabilities, $\alpha_{E1}$ and $\beta_{M1}$, are fundamental properties related to the internal dynamics of the nucleon. The currently accepted values of the proton polarizabilities were determined by fitting to unpolarized proton Compton scattering cross section data. The measurement of the beam asymmetry $\Sigma_{3}$ in a certain kinematical range provides an alternative approach to the extraction of the scalar polarizabilities. At the Mainz Microtron (MAMI) the beam asymmetry was measured for Compton scattering below pion photoproduction threshold for the first time. The results are compared with model calculations and the influence of the experimental data on the extraction of the scalar polarizabilities is determined., Comment: 6 pages, 5 figures

Published
2016
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11. Measurement of the omega -> pi^0 e^+e^- and eta -> e^+e^-g Dalitz decays with the A2 setup at MAMI

Author

Adlarson, P., Afzal, F., Aguar-Bartolomé, P., Ahmed, Z., Annand, J. R. M., Arends, H. J., Bantawa, K., Beck, R., Berghäuser, H., Biroth, M., Borisov, N. S., Braghieri, A., Briscoe, W. J., Cherepnya, S., Cividini, F., Collicott, C., Costanza, S., Danilkin, I. V., Denig, A., Dieterle, M., Downie, E. J., Drexler, P., Bondy, M. I. Ferretti, Fil'kov, L. V., Gardner, S., Garni, S., Glazier, D. I., Glowa, D., Gradl, W., Gurevich, G. M., Hamilton, D. J., Hornidge, D., Huber, G. M., Jude, T. C., Käser, A., Kashevarov, V. L., Kay, S., Keshelashvili, I., Kondratiev, R., Korolija, M., Krusche, B., Lazarev, A., Linturi, J., Lisin, V., Livingston, K., MacGregor, I. J. D., Macrae, R., Manley, D. M., Martel, P. P., McGeorge, J. C., McNicoll, E. F., Metag, V., Middleton, D. G., Miskimen, R., Mornacchi, E., Mullen, C., Mushkarenkov, A., Neganov, A., Neiser, A., Nikolaev, A., Oberle, M., Ostrick, M., Ott, P., Otte, P. B., Paudyal, D., Pedroni, P., Polonski, A., Prakhov, S., Rajabi, A., Robinson, J., Ron, G., Rosner, G., Rostomyan, T., Sfienti, C., Sikora, M. H., Sokhoyan, V., Spieker, K., Steffen, O., Strakovsky, I. I., Strandberg, B., Strub, Th., Supek, I., Thiel, A., Thiel, M., Thomas, A., Unverzagt, M., Usov, Yu. A., Wagner, S., Walford, N., Watts, D. P., Werthmüller, D., Wettig, J., Witthauer, L., Wolfes, M., and Zana, L. A.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

The Dalitz decays eta -> e^+e^-g and omega -> pi^0 e^+e^- have been measured in the g p -> eta p and g p -> omega p reactions, respectively, with the A2 tagged-photon facility at the Mainz Microtron, MAMI. The value obtained for the slope parameter of the electromagnetic transition form factor of eta, Lambda^{-2}_eta=(1.97+/-0.11_tot) GeV^{-2}, is in good agreement with previous measurements of the eta -> e^+e^-g and eta -> mu^+mu^-g decays. The uncertainty obtained in the value of Lambda^{-2}_eta is lower than in previous results based on the eta -> e^+e^-g decay. The value obtained for the omega slope parameter, Lambda^{-2}_omega_pi^0 = (1.99+/-0.21_tot) GeV^{-2}, is somewhat lower than previous measurements based on omega -> pi^0 mu^+mu^-, but the results for the omega transition form factor are in better agreement with theoretical calculations, compared to earlier experiments., Comment: 19 figures, 2 tables

Published
2016
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12. Photon asymmetry measurements of $\overrightarrow{\gamma} \mathrm{p} \rightarrow \pi^{0} \mathrm{p}$ for E$_{\gamma}$=320$-$650 MeV

Author

Gardner, S., Howdle, D., Sikora, M. H., Wunderlich, Y., Abt, S., Achenbach, P., Afzal, F., Aguar-Bartolome, P., Ahmed, Z., Annand, J. R. M., Arends, H. J., Bantawa, K., Bashkanov, M., Beck, R., Biroth, M., Borisov, N. S., Braghieri, A., Briscoe, W. J., Cherepnya, S., Cividini, F., Costanza, S., Collicott, C., Demissie, B. T., Denig, A., Dieterle, M., Downie, E. J., Drexler, P., Ferretti-Bondy, M. I., Filkov, L. V., Glazier, D. I., Garni, S., Gradl, W., Günther, M., Gurevich, G. M., Hamilton, D., Heid, E., Hornidge, D., Huber, G. M., Jahn, O., Jude, T. C., Käser, A., Kay, S., Kashevarov, V. L., Keshelashvili, I., Kondratiev, R., Korolija, M., Krusche, B., Linturi, J. M., Lisin, V., Livingston, K., Lutterer, S., MacGregor, I. J. D., Macrae, R., Mancell, J., Manley, D. M., Martel, P. P., McGeorge, J. C., McNicoll, E. F., Middleton, D. G., Miskimen, R., Mullen, C., Mushkarenkov, A., Neganov, A. B., Neiser, A., Nikolaev, A., Oberle, M., Ostrick, M., Owens, R. O., Otte, P. B., Oussena, B., Paudyal, D., Pedroni, P., Polonski, A., Prakhov, S., Rajabi, A., Robinson, J., Rosner, G., Rostomyan, T., Sarty, A., Schumann, S., Sokhoyan, V., Spieker, K., Steffen, O., Sfienti, C., Strakovsky, I. I., Strandberg, B., Strub, Th., Supek, I., Tarbert, C. M., Thiel, A., Thiel, M., Thomas, A., Unverzagt, M., Usov, Yu. A., Watts, D. P., Werthmüller, D., Wettig, J., Wolfes, M., Witthauer, L., and Zana, L.

Subjects
Nuclear Experiment
Abstract

High statistics measurements of the photon asymmetry $\mathrm{\Sigma}$ for the $\overrightarrow{\gamma}$p$\rightarrow\pi^{0}$p reaction have been made in the center of mass energy range W=1214-1450 MeV. The data were measured with the MAMI A2 real photon beam and Crystal Ball/TAPS detector systems in Mainz, Germany. The results significantly improve the existing world data and are shown to be in good agreement with previous measurements, and with the MAID, SAID, and Bonn-Gatchina predictions. We have also combined the photon asymmetry results with recent cross-section measurements from Mainz to calculate the profile functions, $\check{\mathrm{\Sigma}}$ (= $\sigma_{0}\mathrm{\Sigma}$), and perform a moment analysis. Comparison with calculations from the Bonn-Gatchina model shows that the precision of the data is good enough to further constrain the higher partial waves, and there is an indication of interference between the very small $F$-waves and the $N(1520) 3/2^{-}$ and $N(1535) 1/2^{-}$ resonances.

Published
2016
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14. A Helium Gas-Scintillator Active Target for Photoreaction Measurements

Author

Jebali, R. Al, Annand, J. R. M., Adler, J. -O., Akkurt, I., Buchanan, E., Brudvik, J., Fissum, K., Gardner, S., Hamilton, D. J., Hansen, K., Isaksson, L., Livingston, K., Lundin, M., McGeorge, J. C., MacGregor, I. J. D., MacRae, R., Middleton, D. G., Reiter, A. J. H., Rosner, G., Schröder, B., Sjögren, J., Sokhan, D., and Strandberg, B.

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

A multi-cell He gas-scintillator active target, designed for the measurement of photoreaction cross sections, is described. The target has four main chambers, giving an overall thickness of 0.103 $\mathrm{g/cm^{2}}$ at an operating pressure of 2 MPa. Scintillations are read out by photomultiplier tubes and the addition of small amounts of $\mathrm{N}_{2}$ to the He, to shift the scintillation emission from UV to visible, is discussed. First results of measurements at the MAX IV Laboratory tagged-photon facility show that the target has good timing resolution and can cope well with a high-flux photon beam. The determination of reaction cross sections from target yields relies on a Monte Carlo simulation, which considers scintillation light transport, photodisintegration processes in $^{4}\mathrm{He}$, background photon interactions in target windows and interactions of the reaction-product particles in the gas and target container. The predictions of this simulation are compared to the measured target response., Comment: 24 pages, 15 figures

Published
2015

16. Cold seep formation from salt diapir-controlled deep biosphere oases.

Author

Chowdhury, Anirban, Ventura, Gregory T., Owino, Yaisa, Lalk, Ellen J., MacAdam, Natasha, Dooma, John M., Shuhei Ono, Fowler, Martin, MacDonald, Adam, Bennett, Robbie, MacRae, R. Andrew, Hubert, Casey R. J., Bentley, Jeremy N., and Kerr, Mitchell J.

Subjects
COLD seeps, BIOSPHERE, SALT domes, OCEAN bottom, SALT
Abstract

Deep sea cold seeps are sites where hydrogen sulfide, methane, and other hydrocarbon-rich fluids vent from the ocean floor. They are an important component of Earth's carbon cycle in which subsurface hydrocarbons form the energy source for highly diverse benthic micro-and macro-fauna in what is otherwise vast and spartan sea scape. Passive continental margin cold seeps are typically attributed to the migration of hydrocarbons generated from deeply buried source rocks. Many of these seeps occur over salt tectonic provinces, where the movement of salt generates complex fault systems that can enable fluid migration or create seals and traps associated with reservoir formation. The elevated advective heat transport of the salt also produces a chimney effect directly over these structures. Here, we provide geophysical and geochemical evidence that the salt chimney effect in conjunction with diapiric faulting drives a subsurface groundwater circulation system that brings dissolved inorganic carbon, nutrient-rich deep basinal fluids, and potentially overlying seawater onto the crests of deeply buried salt diapirs. The mobilized fluids fuel methanogenic archaea locally enhancing the deep biosphere. The resulting elevated biogenic methane production, alongside the upward heat-driven fluid transport, represents a previously unrecognized mechanism of cold seep formation and regulation. [ABSTRACT FROM AUTHOR]

Published
2024
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18. The Concise Guide to PHARMACOLOGY 2023/24: G protein-coupled receptors

Author

Alexander, SPH, Christopoulos, A, Davenport, AP, Kelly, E, Mathie, AA, Peters, JA, Veale, EL, Armstrong, JF, Faccenda, E, Harding, SD, Davies, JA, Abbracchio, MP, Abraham, G, Agoulnik, A, Alexander, W, Al-hosaini, K, Back, M, Baker, JG, Barnes, NM, Bathgate, R, Beaulieu, J-M, Beck-Sickinger, AG, Behrens, M, Bernstein, KE, Bettler, B, Birdsall, NJM, Blaho, V, Boulay, F, Bousquet, C, Brauner-Osborne, H, Burnstock, G, Calo, G, Castano, JP, Catt, KJ, Ceruti, S, Chazot, P, Chiang, N, Chini, B, Chun, J, Cianciulli, A, Civelli, O, Clapp, LH, Couture, R, Cox, HM, Csaba, Z, Dahlgren, C, Dent, G, Douglas, SD, Dournaud, P, Eguchi, S, Escher, E, Filardo, EJ, Fong, T, Fumagalli, M, Gainetdinov, RR, Garelja, ML, de Gasparo, M, Gerard, C, Gershengorn, M, Gobeil, F, Goodfriend, TL, Goudet, C, Gratz, L, Gregory, KJ, Gundlach, AL, Hamann, J, Hanson, J, Hauger, RL, Hay, DL, Heinemann, A, Herr, D, Hollenberg, MD, Holliday, ND, Horiuchi, M, Hoyer, D, Hunyady, L, Husain, A, Ijzerman, AP, Inagami, T, Jacobson, KA, Jensen, RT, Jockers, R, Jonnalagadda, D, Karnik, S, Kaupmann, K, Kemp, J, Kennedy, C, Kihara, Y, Kitazawa, T, Kozielewicz, P, Kreienkamp, H-J, Kukkonen, JP, Langenhan, T, Larhammar, D, Leach, K, Lecca, D, Lee, JD, Leeman, SE, Leprince, J, Li, XX, Lolait, SJ, Lupp, A, Macrae, R, Maguire, J, Malfacini, D, Mazella, J, McArdle, CA, Melmed, S, Michel, MC, Miller, LJ, Mitolo, V, Mouillac, B, Mueller, CE, Murphy, PM, Nahon, J-L, Ngo, T, Norel, X, Nyimanu, D, O'Carroll, A-M, Offermanns, S, Panaro, MA, Parmentier, M, Pertwee, RG, Pin, J-P, Prossnitz, ER, Quinn, M, Ramachandran, R, Ray, M, Reinscheid, RK, Rondard, P, Rovati, GE, Ruzza, C, Sanger, GJ, Schoeneberg, T, Schulte, G, Schulz, S, Segaloff, DL, Serhan, CN, Singh, KD, Smith, CM, Stoddart, LA, Sugimoto, Y, Summers, R, Tan, VP, Thal, D, Thomas, WW, Timmermans, PBMWM, Tirupula, K, Toll, L, Tulipano, G, Unal, H, Unger, T, Valant, C, Vanderheyden, P, Vaudry, D, Vaudry, H, Vilardaga, J-P, Walker, CS, Wang, JM, Ward, DT, Wester, H-J, Willars, GB, Williams, TL, Woodruff, TM, Yao, C, Ye, RD, Alexander, SPH, Christopoulos, A, Davenport, AP, Kelly, E, Mathie, AA, Peters, JA, Veale, EL, Armstrong, JF, Faccenda, E, Harding, SD, Davies, JA, Abbracchio, MP, Abraham, G, Agoulnik, A, Alexander, W, Al-hosaini, K, Back, M, Baker, JG, Barnes, NM, Bathgate, R, Beaulieu, J-M, Beck-Sickinger, AG, Behrens, M, Bernstein, KE, Bettler, B, Birdsall, NJM, Blaho, V, Boulay, F, Bousquet, C, Brauner-Osborne, H, Burnstock, G, Calo, G, Castano, JP, Catt, KJ, Ceruti, S, Chazot, P, Chiang, N, Chini, B, Chun, J, Cianciulli, A, Civelli, O, Clapp, LH, Couture, R, Cox, HM, Csaba, Z, Dahlgren, C, Dent, G, Douglas, SD, Dournaud, P, Eguchi, S, Escher, E, Filardo, EJ, Fong, T, Fumagalli, M, Gainetdinov, RR, Garelja, ML, de Gasparo, M, Gerard, C, Gershengorn, M, Gobeil, F, Goodfriend, TL, Goudet, C, Gratz, L, Gregory, KJ, Gundlach, AL, Hamann, J, Hanson, J, Hauger, RL, Hay, DL, Heinemann, A, Herr, D, Hollenberg, MD, Holliday, ND, Horiuchi, M, Hoyer, D, Hunyady, L, Husain, A, Ijzerman, AP, Inagami, T, Jacobson, KA, Jensen, RT, Jockers, R, Jonnalagadda, D, Karnik, S, Kaupmann, K, Kemp, J, Kennedy, C, Kihara, Y, Kitazawa, T, Kozielewicz, P, Kreienkamp, H-J, Kukkonen, JP, Langenhan, T, Larhammar, D, Leach, K, Lecca, D, Lee, JD, Leeman, SE, Leprince, J, Li, XX, Lolait, SJ, Lupp, A, Macrae, R, Maguire, J, Malfacini, D, Mazella, J, McArdle, CA, Melmed, S, Michel, MC, Miller, LJ, Mitolo, V, Mouillac, B, Mueller, CE, Murphy, PM, Nahon, J-L, Ngo, T, Norel, X, Nyimanu, D, O'Carroll, A-M, Offermanns, S, Panaro, MA, Parmentier, M, Pertwee, RG, Pin, J-P, Prossnitz, ER, Quinn, M, Ramachandran, R, Ray, M, Reinscheid, RK, Rondard, P, Rovati, GE, Ruzza, C, Sanger, GJ, Schoeneberg, T, Schulte, G, Schulz, S, Segaloff, DL, Serhan, CN, Singh, KD, Smith, CM, Stoddart, LA, Sugimoto, Y, Summers, R, Tan, VP, Thal, D, Thomas, WW, Timmermans, PBMWM, Tirupula, K, Toll, L, Tulipano, G, Unal, H, Unger, T, Valant, C, Vanderheyden, P, Vaudry, D, Vaudry, H, Vilardaga, J-P, Walker, CS, Wang, JM, Ward, DT, Wester, H-J, Willars, GB, Williams, TL, Woodruff, TM, Yao, C, and Ye, RD

Abstract

The Concise Guide to PHARMACOLOGY 2023/24 is the sixth in this series of biennial publications. The Concise Guide provides concise overviews, mostly in tabular format, of the key properties of approximately 1800 drug targets, and about 6000 interactions with about 3900 ligands. There is an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (https://www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. Although the Concise Guide constitutes almost 500 pages, the material presented is substantially reduced compared to information and links presented on the website. It provides a permanent, citable, point-in-time record that will survive database updates. The full contents of this section can be found at http://onlinelibrary.wiley.com/doi/bph.16177. G protein-coupled receptors are one of the six major pharmacological targets into which the Guide is divided, with the others being: ion channels, nuclear hormone receptors, catalytic receptors, enzymes and transporters. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. The landscape format of the Concise Guide is designed to facilitate comparison of related targets from material contemporary to mid-2023, and supersedes data presented in the 2021/22, 2019/20, 2017/18, 2015/16 and 2013/14 Concise Guides and previous Guides to Receptors and Channels. It is produced in close conjunction with the Nomenclature and Standards Committee of the International Union of Basic and Clinical Pharmacology (NC-IUPHAR), therefore, providing official IUPHAR classification and nomenclature for human drug targets, where appropriate.

Published
2023

19. Discovery of Visean to early Serpukhovian (Mississippian) aged tetrapod burrows from Midland and Lepreau Falls, New Brunswick, Canada: an ichnological, palynological and seismic investigation of the Millstream Subbasin

Author

Stimson, Matthew, Hinds, Steven, King, Olivia, Dafoe, Lynn, Macrae, R. Andrew, and Park, Adrian

Subjects
Nova Scotia -- Environmental aspects, Vertebrates -- Environmental aspects -- Behavior, Basins (Geology) -- Environmental aspects, Fossils -- Environmental aspects -- Physiological aspects, Earth sciences
Abstract

During the spring of 2018, residents Gary, David, and Rick Leblanc, found a near-horizontal burrow fossil within red sandstone along a ditch outcrop at Midland, New Brunswick. These red sandstones, [...]

Published
2022

20. Palynology of the Albert Formation of New Brunswick, Canada

Author

King, Olivia, Macrae, R. Andrew, Stimson, Matthew, Hinds, Steven, Park, Adrian, and Mclean, Duncan

Subjects
New Brunswick -- Natural history, Paleontology, Stratigraphic -- Research, Rock formations -- Environmental aspects, Palynology -- Research, Formations (Geology) -- Environmental aspects, Geological research, Earth sciences
Abstract

A palynological (plant spores) biostratigraphic study of the Tournaisian (Early Carboniferous) aged sites between the townships of Bloomfield and Norton, New Brunswick is being conducted. Newly collected and historical samples [...]

Published
2022

21. Determination of the scalar polarizabilities of the proton using beam asymmetry Σ 3 in Compton scattering

Author

Sokhoyan, V., Downie, E. J., Mornacchi, E., McGovern, J. A., Krupina, N., Afzal, F., Ahrens, J., Akondi, C. S., Annand, J. R. M., Arends, H. J., Beck, R., Braghieri, A., Briscoe, W. J., Cividini, F., Collicott, C., Costanza, S., Denig, A., Dieterle, M., Ferretti, M., Gardner, S., Garni, S., Glazier, D. I., Glowa, D., Gradl, W., Gurevich, G., Hamilton, D., Hornidge, D., Huber, G. M., Käser, A., Kashevarov, V. L., Keshelashvili, I., Kondratiev, R., Korolija, M., Krusche, B., Lensky, V., Linturi, J., Lisin, V., Livingston, K., MacGregor, I. J. D., Macrae, R., Manley, D. M., Martel, P. P., Middleton, D. G., Miskimen, R., Mushkarenkov, A., Neiser, A., Oberle, M., Ortega Spina, H., Ostrick, M., Ott, P., Otte, P. B., Oussena, B., Paudyal, D., Pedroni, P., Polonski, A., Prakhov, S., Rajabi, A., Rostomyan, T., Sarty, A., Schumann, S., Spieker, K., Steffen, O., Strakovsky, I. I., Strandberg, B., Strub, T., Supek, I., Thiel, A., Thiel, M., Thomas, A., Unverzagt, M., Wagner, S., Watts, D. P., Wettig, J., Witthauer, L., Werthmüller, D., Wolfes, M., Zana, L., and The A2 Collaboration

Published
2017
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28. Generative adversarial neural networks maintain decoder accuracy during signal disruption in simulated long-term recordings from brain computer interfaces

Author

Simons S, Cafaro J, MacRae R, and Stephens T

Subjects
Artificial neural network, Computer science, business.industry, Interface (computing), Stability (learning theory), Image translation, Pattern recognition, Artificial intelligence, Set (psychology), business, Signal, Brain–computer interface, Term (time)
Abstract

Chronically implanted brain-computer interfaces (BCIs) provide amazing opportunities to those living with disability and for the treatment of chronic disorders of the nervous system. However, this potential has yet to be fully realized in part due to the lack of stability in measured signals over time. Signal disruption stems from multiple sources including mechanical failure of the interface, changes in neuron health, and glial encapsulation of the electrodes that alter the impedance. In this study we present an algorithmic solution to the problem of long-term signal disruption in chronically implanted neural interfaces. Our approach utilizes a generative adversarial network (GAN), based on the original Unsupervised Image to Image Translation (UNIT) algorithm, which learns how to recover degraded signals back to their analogous non-disrupted (“clean”) exemplars measured at the time of implant. We demonstrate that this approach can reliably recover simulated signals in two types of commonly used neural interfaces: multi-electrode arrays (MEA), and electrocorticography (ECoG). To test the accuracy of signal recovery we employ a common BCI paradigm wherein a classification algorithm (neural decoder) is trained on the starting (non-disrupted) set of signals. Performance of the decoder demonstrates expected failure over time as the signal disruption accumulates. In simulated MEA experiments, our approach recovers decoder accuracy to >90% when as many as 13/ 32 channels are lost, or as many as 28/32 channels have their neural responses altered. In simulated ECoG experiments, our approach shows stabilization of the neural decoder indefinitely with decoder accuracies >95% over simulated lifetimes of over 1 year. Our results suggest that these types of neural networks can provide a useful tool to improve the long-term utility of chronically implanted neural interfaces.

Published
2021
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32. THE CONCISE GUIDE TO PHARMACOLOGY 2021/22: G protein-coupled receptors

Author

Alexander, SPH, Christopoulos, A, Davenport, AP, Kelly, E, Mathie, A, Peters, JA, Veale, EL, Armstrong, JF, Faccenda, E, Harding, SD, Pawson, AJ, Southan, C, Davies, JA, Abbracchio, MP, Alexander, W, Al-hosaini, K, Baeck, M, Barnes, NM, Bathgate, R, Beaulieu, J-M, Bernstein, KE, Bettler, B, Birdsall, NJM, Blaho, V, Boulay, F, Bousquet, C, Braeuner-Osborne, H, Burnstock, G, Calo, G, Castano, JP, Catt, K, Ceruti, S, Chazot, P, Chiang, N, Chini, B, Chun, J, Cianciulli, A, Civelli, O, Clapp, LH, Couture, R, Csaba, Z, Dahlgren, C, Dent, G, Singh, KD, Douglas, SD, Dournaud, P, Eguchi, S, Escher, E, Filardo, EJ, Fong, T, Fumagalli, M, Gainetdinov, RR, de Gasparo, M, Gerard, C, Gershengorn, M, Gobeil, F, Goodfriend, TL, Goudet, C, Gregory, KJ, Gundlach, AL, Hamann, J, Hanson, J, Hauger, RL, Hay, DL, Heinemann, A, Hollenberg, MD, Holliday, ND, Horiuchi, M, Hoyer, D, Hunyady, L, Husain, A, IJzerman, AP, Inagami, T, Jacobson, KA, Jensen, RT, Jockers, R, Jonnalagadda, D, Karnik, S, Kaupmann, K, Kemp, J, Kennedy, C, Kihara, Y, Kitazawa, T, Kozielewicz, P, Kreienkamp, H-J, Kukkonen, JP, Langenhan, T, Leach, K, Lecca, D, Lee, JD, Leeman, SE, Leprince, J, Li, XX, Williams, TL, Lolait, SJ, Lupp, A, Macrae, R, Maguire, J, Mazella, J, McArdle, CA, Melmed, S, Michel, MC, Miller, LJ, Mitolo, V, Mouillac, B, Mueller, CE, Murphy, P, Nahon, J-L, Ngo, T, Norel, X, Nyimanu, D, Ocarroll, A-M, Offermanns, S, Panaro, MA, Parmentier, M, Pertwee, RG, Pin, J-P, Prossnitz, ER, Quinn, M, Ramachandran, R, Ray, M, Reinscheid, RK, Rondard, P, Rovati, GE, Ruzza, C, Sanger, GJ, Schoeneberg, T, Schulte, G, Schulz, S, Segaloff, DL, Serhan, CN, Stoddart, LA, Sugimoto, Y, Summers, R, Tan, VP, Thal, D, Thomas, WW, Timmermans, PMWM, Tirupula, K, Tulipano, G, Unal, H, Unger, T, Valant, C, Vanderheyden, P, Vaudry, D, Vaudry, H, Vilardaga, J-P, Walker, CS, Wang, JM, Ward, DT, Wester, H-J, Willars, GB, Woodruff, TM, Yao, C, Ye, RD, Alexander, SPH, Christopoulos, A, Davenport, AP, Kelly, E, Mathie, A, Peters, JA, Veale, EL, Armstrong, JF, Faccenda, E, Harding, SD, Pawson, AJ, Southan, C, Davies, JA, Abbracchio, MP, Alexander, W, Al-hosaini, K, Baeck, M, Barnes, NM, Bathgate, R, Beaulieu, J-M, Bernstein, KE, Bettler, B, Birdsall, NJM, Blaho, V, Boulay, F, Bousquet, C, Braeuner-Osborne, H, Burnstock, G, Calo, G, Castano, JP, Catt, K, Ceruti, S, Chazot, P, Chiang, N, Chini, B, Chun, J, Cianciulli, A, Civelli, O, Clapp, LH, Couture, R, Csaba, Z, Dahlgren, C, Dent, G, Singh, KD, Douglas, SD, Dournaud, P, Eguchi, S, Escher, E, Filardo, EJ, Fong, T, Fumagalli, M, Gainetdinov, RR, de Gasparo, M, Gerard, C, Gershengorn, M, Gobeil, F, Goodfriend, TL, Goudet, C, Gregory, KJ, Gundlach, AL, Hamann, J, Hanson, J, Hauger, RL, Hay, DL, Heinemann, A, Hollenberg, MD, Holliday, ND, Horiuchi, M, Hoyer, D, Hunyady, L, Husain, A, IJzerman, AP, Inagami, T, Jacobson, KA, Jensen, RT, Jockers, R, Jonnalagadda, D, Karnik, S, Kaupmann, K, Kemp, J, Kennedy, C, Kihara, Y, Kitazawa, T, Kozielewicz, P, Kreienkamp, H-J, Kukkonen, JP, Langenhan, T, Leach, K, Lecca, D, Lee, JD, Leeman, SE, Leprince, J, Li, XX, Williams, TL, Lolait, SJ, Lupp, A, Macrae, R, Maguire, J, Mazella, J, McArdle, CA, Melmed, S, Michel, MC, Miller, LJ, Mitolo, V, Mouillac, B, Mueller, CE, Murphy, P, Nahon, J-L, Ngo, T, Norel, X, Nyimanu, D, Ocarroll, A-M, Offermanns, S, Panaro, MA, Parmentier, M, Pertwee, RG, Pin, J-P, Prossnitz, ER, Quinn, M, Ramachandran, R, Ray, M, Reinscheid, RK, Rondard, P, Rovati, GE, Ruzza, C, Sanger, GJ, Schoeneberg, T, Schulte, G, Schulz, S, Segaloff, DL, Serhan, CN, Stoddart, LA, Sugimoto, Y, Summers, R, Tan, VP, Thal, D, Thomas, WW, Timmermans, PMWM, Tirupula, K, Tulipano, G, Unal, H, Unger, T, Valant, C, Vanderheyden, P, Vaudry, D, Vaudry, H, Vilardaga, J-P, Walker, CS, Wang, JM, Ward, DT, Wester, H-J, Willars, GB, Woodruff, TM, Yao, C, and Ye, RD

Abstract

The Concise Guide to PHARMACOLOGY 2021/22 is the fifth in this series of biennial publications. The Concise Guide provides concise overviews, mostly in tabular format, of the key properties of nearly 1900 human drug targets with an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. Although the Concise Guide constitutes over 500 pages, the material presented is substantially reduced compared to information and links presented on the website. It provides a permanent, citable, point-in-time record that will survive database updates. The full contents of this section can be found at http://onlinelibrary.wiley.com/doi/bph.15538. G protein-coupled receptors are one of the six major pharmacological targets into which the Guide is divided, with the others being: ion channels, nuclear hormone receptors, catalytic receptors, enzymes and transporters. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. The landscape format of the Concise Guide is designed to facilitate comparison of related targets from material contemporary to mid-2021, and supersedes data presented in the 2019/20, 2017/18, 2015/16 and 2013/14 Concise Guides and previous Guides to Receptors and Channels. It is produced in close conjunction with the Nomenclature and Standards Committee of the International Union of Basic and Clinical Pharmacology (NC-IUPHAR), therefore, providing official IUPHAR classification and nomenclature for human drug targets, where appropriate.

Published
2021

33. A revised biostratigraphic and well-log sequence-stratigraphic framework for the Scotian Margin, offshore eastern Canada

Author

Weston, Janice F., MacRae, R. Andrew, Ascoli, Piero, Cooper, M. Kevin E., Fensome, Robert A., Shaw, David, and Williams, Graham L.

Subjects
Paleontology, Stratigraphic -- Research, Geomorphology -- Research, Wells -- Natural history, Earth sciences
Abstract

In this study, we build on a foundation of previous biostratigraphic studies for the Scotian Basin, offshore eastern Canada, by conducting new quantitative multidisciplinary biostratigraphic studies of the Mesozoic sections in eight wells: Bonnet P-23, Chebucto K-90, Cohasset L-97, Glenelg J-48, Glooscap C-63, Mohican I-100, South Desbarres O- 76, and South Griffin J-13. These wells were chosen to provide good spatial coverage, stratigraphic penetration, and correlation with the seismic grid. We have also evaluated pre-existing biostratigraphic data and undertaken the well- log sequence-stratigraphic interpretation of Upper Triassic to Cenozoic sediments in 16 additional wells using a consistent multidisciplinary event scheme derived from the new wells. Key to the dating of some horizons has been integration of the palynology and micropaleontology (disciplines mostly used previously on the Scotian Margin) with new nannofossil data. Simultaneously we have closely integrated the biostratigraphic results with lithofacies, well-log, and seismic interpretations. Using this integrated approach, we have identified nine regionally mappable sequence-stratigraphic events (unconformities and maximum flooding surfaces, or MFSs): the Intra-Oligocene Unconformity; the Ypresian Unconformity; the Turonian/Cenomanian Unconformity; the Late Albian Unconformity; the Aptian/Barremian Unconformity; the Intra-Hauterivian MFS; the Near-Base Cretaceous Unconformity; the Tithonian MFS; and the Top-Callovian MFS. Additional events of local extent were also recognized in some wells. Our study has led to significant revision of some previous lithostratigraphic picks. The Early Jurassic on the Scotian Margin remains poorly resolved and may be represented by an unconformity on much of the basin periphery. Dans la presente etude, nous mettons a profit une base d'etudes biostratigraphiques anterieures pour le bassin Scotian, au large de l'Est du Canada, en effectuant de nouvelles etudes biostratigraphiques quantitatives multidisciplinaires des sections mesozo'iques dans huit puits : Bonnet P-23, Chebucto K-90, Cohasset L-97, Glenelg J-48, Glooscap C-63, Mohican I-100, South Desbarres O-76 et South Griffin J-13. Ces puits ont ete choisis afin de fournir une bonne couverture spatiale, une penetration stratigraphique et une correlation avec le reseau sismique. Nous avons aussi evalue les donnees biostratigraphiques existantes et nous avons entrepris l'interpretation de la diagraphie de la sequence stratigraphique des sediments du Trias superieur au Cenozo'que dans 16 puits additionnels en utilisant un plan d'evenements multidisciplinaires constants derive des nouveaux puits. La cle de la datation de certains horizons a ete l'integration de la palynologie et de la micropaleontologie (des disciplines surtout utilisees anterieurement sur la bordure Scotian) avec de nouvelles donnees de nannofossiles. En meme temps, nous avons soigneusement integre les resultats biostratigraphiques avec les lithofacies, les diagraphies et les interpretations sismiques. En utilisant cette approche integree, nous avons identifie neuf evenements cartographiables de sequences stratigraphiques (discordances et surfaces maximales d'inondation) : la discordance Intra-Oligocene, la discordance a l'Ypresien, la discordance au Turonien/Cenomanien, la discordance a l'Albien tardif, la discordance a l'Aptien/Barremien, la surface maximale d'inondation Intra-Hauterivien, la discordance pres de la base du Cretace, la surface maximale d'inondation du Tithonien et la surface maximale d'inondation du sommet du Callovien. D'autres evenements d'etendue locale ont aussi ete reconnus dans certains puits. Notre etude a conduit a une revision importante de certaines designations lithostratigraphiques. Le Jurassique precoce a la bordure Scotian demeure mal resolu et pourrait etre represente par une discordance sur une grande portion de la peripherie du bassin. [Traduit par la Redaction], Introduction The Scotian Margin is that region underlain by the continental shelf (Scotian Shelf) and slope (Scotian Slope) off Nova Scotia, southeastern Canada (Fig. 1A). It is part of the [...]

Published
2012
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35. Measurement of the beam-helicity asymmetry in photoproduction of π0η pairs on carbon, aluminum, and lead

Author

Sokhoyan, V., Prakhov, S., Fix, A., Abt, S., Achenbach, P., Adlarson, P., Afzal, F., Aguar-Bartolomé, P., Ahmed, Z., Altangerel, K., Annand, J.R.M., Arends, H.J., Bantawa, K., Bashkanov, M., Beck, R., Biroth, M., Borisov, N.S., Braghieri, A., Briscoe, W.J., Cherepnya, S., Cividini, F., Collicott, C., Costanza, S., Denig, A., Dieterle, M., Downie, E.J., Drexler, P., Ferretti Bondy, M.I., Fil'kov, L.V., Gardner, S., Garni, S., Glazier, D.I., Gorodnov, I., Gradl, W., Günther, M., Gurevich, G.M., Heijkenskjöld, L., Hornidge, D., Huber, G.M., Käser, A., Kashevarov, V.L., Kay, S., Keshelashvili, I., Kondratiev, R., Korolija, M., Krusche, B., Lazarev, A., Livingston, K., Lutterer, S., MacGregor, I.J.D., Macrae, R., Manley, D.M., Martel, P.P., McGeorge, J.C., Middleton, D.G., Miskimen, R., Mornacchi, E., Mullen, C., Mushkarenkov, A., Neganov, A., Neiser, A., Oberle, M., Ostrick, M., Otte, P.B., Paudyal, D., Pedroni, P., Powell, A., Rickert, E., Ron, G., Rostomyan, T., Sarty, A., Sfienti, C., Spieker, K., Steffen, O., Strakovsky, I.I., Strandberg, B., Strub, Th., Supek, I., Thiel, A., Thiel, M., Thomas, A., Unverzagt, M., Usov, Yu.A., Wagner, S., Walford, N.K., Watts, D.P., Werthmüller, D., Wettig, J., Witthauer, L., Wolfes, M., and Zachariou, N.

Published
2020
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37. Modifying walking football for people living with dementia: lessons for best practice.

Author

MacRae, R., Macrae, E., and Carlin, L.

Subjects
SPORTS participation, DEMENTIA, BEST practices, OLDER people, SOCIAL impact, MENTAL health
Abstract

Inclusive and modified sport promotes opportunities for participation usually for older people or people with disabilities, physical and or mental health issues. Walking sports, a form of modified sport, is often designed to support engagement in physical and social activity amongst people over 50 years. This qualitative study explored how walking football sessions were designed and delivered for, and experienced by people living with dementia and their family carers. We thematically analysed 18 qualitative interviews and identified three main themes (1) social impact, (2) embodied memories and (3) flexible carer respite. The findings increase our understanding of how walking sports such as football can be viewed as a psychosocial intervention and be modified to promote the inclusion and agency of people living with dementia and respite for family carers. The study offers best practice recommendations for those organising modified sports activities for older people living with dementia. [ABSTRACT FROM AUTHOR]

Published
2022
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38. The last 100 million years on the Scotian Margin, offshore eastern Canada: an event-stratigraphic scheme emphasizing biostratigraphic data

Author

Fensome, Robert A., Crux, Jason A., Gard, I. Gunilla, MacRae, R. Andrew, Williams, Graham L., Thomas, Frank C., Fiorini, Flavia, and Wach, Grant

Subjects
Cambridge University Press -- Market research, Chemical oceanography -- Case studies, Oil and gas exploration -- Case studies -- Market research, Book publishing -- Case studies -- Market research, Earth sciences, Marketing research, Market research, Case studies
Abstract

ABSTRACT In order to provide a detailed stratigraphic framework for the Late Cretaceous and Cenozoic basin fill of the Scotian Margin (the continental shelf and continental slope off Nova Scotia, [...]

Published
2008

39. Measurement of the beam-helicity asymmetry in photoproduction of π0η pairs on carbon, aluminum, and lead

Author

Livingston, K., Lutterer, S., MacGregor, I. J.D., Macrae, R., Manley, D. M., Martel, P. P., McGeorge, J. C., Middleton, D.G., Miskimen, R., Mornacchi, E., Mullen, C., Mushkarenkov, A., Neganov, A., Neiser, A., Oberle, M., Ostrick, M., Otte, P. B., Paudyal, D., and Pedroni, P.

Subjects
Nuclear Theory, High Energy Physics::Experiment, Nuclear Experiment
Abstract

The beam-helicity asymmetry was measured, for the first time, in photoproduction of $\pi^{0}\eta$ pairs on carbon, aluminum, and lead, with the A2 experimental setup at MAMI. The results are compared to an earlier measurement on a free proton and to the corresponding theoretical calculations. The Mainz model is used to predict the beam-helicity asymmetry for the nuclear targets. The present results indicate that the photoproduction mechanism for $\pi^{0}\eta$ pairs on nuclei is similar to photoproduction on a free nucleon. This process is dominated by the $D_{33}$ partial wave with the $\eta\Delta(1232)$ intermediate state.

Published
2020

40. Measurement of the beam-helicity asymmetry in photoproduction of Pairs on Carbon, Aluminum, and Lead

Author

Sokhoyan, V., Prakhov, S., Fix, A., Abt, S., Achenbach, P., Adlarson, P., Afzal, F., Aguar-Bartolomé, P., Ahmed, Z., Altangerel, K., Annand, J.R.M., Arends, H.J., Bantawa, K., Bashkanov, M., Beck, R., Biroth, M., Borisov, N.S., Braghieri, A., Briscoe, W.J., Cherepnya, S., Cividini, F., Collicott, C., Costanza, S., Denig, A., Dieterle, M., Downie, E.J., Drexler, P., Ferretti Bondy, M.I., Fil'kov, L.V., Gardner, S., Garni, S., Glazier, D.I., Gorodnov, I., Gradl, W., Günther, M., Gurevich, G.M., Heijkenskjöld, L., Hornidge, D., Huber, G.M., Käser, A., Kashevarov, V.L., Kay, S., Keshelashvili, I., Kondratiev, R., Korolija, M., Krusche, B., Lazarev, A., Livingston, K., Lutterer, S., MacGregor, I.J.D., Macrae, R., Manley, D.M., Martel, P.P., McGeorge, J.C., Middleton, D.G., Miskimen, R., Mornacchi, E., Mullen, C., Mushkarenkov, A., Neganov, A., Neiser, A., Oberle, M., Ostrick, M., Otte, P.B., Paudyal, D., Pedroni, P., Powell, A., Rickert, E., Ron, G., Rostomyan, T., Sarty, A., Sfienti, C., Spieker, K., Steffen, O., Strakovsky, I.I., Strandberg, B., Strub, Th., Supek, I., Thiel, A., Thiel, M., Thomas, A., Unverzagt, M., Usov, Yu.A., Wagner, S., Walford, N.K., Watts, D.P., Werthmüller, D., Wettig, J., Witthauer, L., Wolfes, M., and Zachariou, N.

Abstract

The beam-helicity asymmetry was measured, for the first time, in photoproduction of π0η pairs on carbon, aluminum, and lead, with the A2 experimental setup at MAMI. The results are compared to an earlier measurement on a free proton and to the corresponding theoretical calculations. The Mainz model is used to predict the beam-helicity asymmetry for the nuclear targets. The present results indicate that the photoproduction mechanism for π0η pairs on nuclei is similar to photoproduction on a free nucleon. This process is dominated by the D33 partial wave with the ηΔ(1232) intermediate state.

Published
2020

41. Middle Albian (Lower Cretaceous) Gastroplitinid ammonites and dinoflagellates from the Christopher Formation (Dragon Mountain, Axel Heiberg island, Canadian Arctic Islands) and a revision of the genus Pseudogastroplites Jeletzky, 1980

Author

Hall, Russell L., Macrae, R. Andrew, and Hills, L.V.

Subjects
Ammonoidea -- Discovery and exploration, Paleontology -- Research, Biological sciences, Science and technology
Abstract

A large sample of excellently preserved ammonites from concretions concentrated at a single horizon near the base of the Macdougall Point Member of the Christopher Formation (Aptian--Albian age; Early Cretaceous) is the basis for recognizing a new species of the boreal ammonite genus Pseudogastroplites (P. draconensis). The dimorphic nature of the genus is established, two variants are recognized (P. draconensis var. robusta and P. draconensis var. gracile), and the generic diagnosis is emended. Retention of the genus Pseudogastroplites Jeletzky, 1980 as distinct from Gastroplites McLearn, 1930 is proposed. The concretions also yield Pseudopulchellia flexicostata (Imlay, 1961), inoceramid bivalves, fish remains, and a palynological flora, and are dated as late middle Albian.

Published
2005

44. Deuteron photodisintegration by polarized photons in the region of the d⁎(2380)

Author

Bashkanov, M., Kay, S., Watts, D.P., Mullen, C., Abt, S., Achenbach, P., Adlarson, P., Afzal, F., Ahmed, Z., Akondi, C.S., Annand, J.R.M., Arends, H.J., Beck, R., Biroth, M., Borisov, N., Braghieri, A., Briscoe, W.J., Cividini, F., Collicott, C., Costanza, S., Denig, A., Downie, E.J., Drexler, P., Garni, S., Glazier, D.I., Gorodnov, I., Gradl, W., Günther, M., Gurevich, D., Heijkenskjöld, L., Hornidge, D., Huber, G.M., Käser, A., Kashevarov, V.L., Korolija, M., Krusche, B., Lazarev, A., Livingston, K., Lutterer, S., MacGregor, I.J.D., Macrae, R., Manley, D.M., Martel, P.P., Miskimen, R., Mornacchi, E., Neganov, A., Neiser, A., Ostrick, M., Otte, P.B., Paudyal, D., Pedroni, P., Powell, A., Prakhov, S.N., Ron, G., Rostomyan, T., Sarty, A., Sfienti, C., Sokhoyan, V., Spieker, K., Steffen, O., Strakovsky, I.I., Strub, T., Supek, I., Thiel, A., Thiel, M., Thomas, A., Usov, Yu.A., Wagner, S., Walford, N.K., Werthmüller, D., Wettig, J., Wolfes, M., and Zana, L.A.

Published
2019
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