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1. GAPS contributions to the 38th International Cosmic Ray Conference (Nagoya 2023)

Author

Aramaki, T., Boezio, M., Boggs, S. E., Bonvicini, V., Bridges, G., Campana, D., Craig, W. W., von Doetinchem, P., Everson, E., Fabris, L., Feldman, S., Fuke, H., Gahbauer, F., Gerrity, C., Ghislotti, L., Hailey, C. J., Hayashi, T., Kawachi, A., Kozai, M., Lazzaroni, P., Law, M., Lenni, A., Lowell, A., Manghisoni, M., Marcelli, N., Mizukoshi, K., Mocchiutti, E., Mochizuki, B., Mognet, S. A. I., Munakata, K., Munini, R., Okazaki, S., Olson, J., Ong, R. A., Osteria, G., Perez, K., Perfetto, F., Quinn, S., Re, V., Riceputi, E., Roach, B., Rogers, F., Ryan, J. L., Saffold, N., Scotti, V., Shimizu, Y., Shutt, K., Sparvoli, R., Stoessl, A., Tiberio, A., Vannuccini, E., Xiao, M., Yamatani, M., Yee, K., Yoshida, T., Zampa, G., Zeng, J., and Zweerink, J.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

Compilation of papers presented by the GAPS Collaboration at the 38th International Cosmic Ray Conference (ICRC), held July 26 through August 3, 2023 in Nagoya, Japan.

Published
2023

2. Cosmic antihelium-3 nuclei sensitivity of the GAPS experiment

Author

Saffold, N., Aramaki, T., Bird, R., Boezio, M., Boggs, S. E., Bonvicini, V., Campana, D., Craig, W. W., von Doetinchem, P., Everson, E., Fabris, L., Fuke, H., Gahbauer, F., Garcia, I., Gerrity, C., Hailey, C. J., Hayashi, T., Kato, C., Kawachi, A., Kobayashi, S., Kozai, M., Lenni, A., Lowell, A., Manghisoni, M., Marcelli, N., Mognet, S. I., Munakata, K., Munini, R., Nakagami, Y., Olson, J., Ong, R. A., Osteria, G., Perez, K., Pope, I., Quinn, S., Re, V., Reed, M., Riceputi, E., Roach, B., Rogers, F., Ryan, J. L., Scotti, V., Shimizu, Y., Sonzogni, M., Sparvoli, R., Stoessl, A., Tiberio, A., Vannuccini, E., Wada, T., Xiao, M., Yamatani, M., Yoshida, A., Yoshida, T., Zampa, G., and Zweerink, J.

Subjects
High Energy Physics - Phenomenology, Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Experiment
Abstract

The General Antiparticle Spectrometer (GAPS) is an Antarctic balloon experiment designed for low-energy (0.1$-$0.3 GeV/$n$) cosmic antinuclei as signatures of dark matter annihilation or decay. GAPS is optimized to detect low-energy antideuterons, as well as to provide unprecedented sensitivity to low-energy antiprotons and antihelium nuclei. The novel GAPS antiparticle detection technique, based on the formation, decay, and annihilation of exotic atoms, provides greater identification power for these low-energy antinuclei than previous magnetic spectrometer experiments. This work reports the sensitivity of GAPS to detect antihelium-3 nuclei, based on full instrument simulation, event reconstruction, and realistic atmospheric influence simulations. The report of antihelium nuclei candidate events by AMS-02 has generated considerable interest in antihelium nuclei as probes of dark matter and other beyond the Standard Model theories. GAPS is in a unique position to detect or set upper limits on the cosmic antihelium nuclei flux in an energy range that is essentially free of astrophysical background. In three 35-day long-duration balloon flights, GAPS will be sensitive to an antihelium flux on the level of $1.3^{+4.5}_{-1.2}\cdot 10^{-6}\mathrm{m^{-2}sr^{-1}s^{-1}}(\mathrm{GeV}/n)^{-1}$ (95% confidence level) in the energy range of 0.11$-$0.3 GeV/$n$, opening a new window on rare cosmic physics., Comment: Accepted for publication at Astroparticle Physics, 13 pages, 5 figures

Published
2020
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3. Sensitivity of the GAPS experiment to low-energy cosmic-ray antiprotons

Author

Rogers, F., Aramaki, T., Boezio, M., Boggs, S.E., Bonvicini, V., Bridges, G., Campana, D., Craig, W.W., von Doetinchem, P., Everson, E., Fabris, L., Feldman, S., Fuke, H., Gahbauer, F., Gerrity, C., Hailey, C.J., Hayashi, T., Kawachi, A., Kozai, M., Lenni, A., Lowell, A., Manghisoni, M., Marcelli, N., Mochizuki, B., Mognet, S.A.I., Munakata, K., Munini, R., Nakagami, Y., Olson, J., Ong, R.A., Osteria, G., Perez, K.M., Quinn, S., Re, V., Riceputi, E., Roach, B., Ryan, J., Saffold, N., Scotti, V., Shimizu, Y., Sparvoli, R., Stoessl, A., Tiberio, A., Vannuccini, E., Wada, T., Xiao, M., Yamatani, M., Yee, K., Yoshida, A., Yoshida, T., Zampa, G., Zeng, J., and Zweerink, J.

Published
2023
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4. Cosmic antihelium-3 nuclei sensitivity of the GAPS experiment

Author

Saffold, N., Aramaki, T., Bird, R., Boezio, M., Boggs, S.E., Bonvicini, V., Campana, D., Craig, W.W., von Doetinchem, P., Everson, E., Fabris, L., Fuke, H., Gahbauer, F., Garcia, I., Gerrity, C., Hailey, C.J., Hayashi, T., Kato, C., Kawachi, A., Kobayashi, S., Kozai, M., Lenni, A., Lowell, A., Manghisoni, M., Marcelli, N., Mognet, S.I., Munakata, K., Munini, R., Nakagami, Y., Olson, J., Ong, R.A., Osteria, G., Perez, K., Pope, I., Quinn, S., Re, V., Reed, M., Riceputi, E., Roach, B., Rogers, F., Ryan, J.L., Scotti, V., Shimizu, Y., Sonzogni, M., Sparvoli, R., Stoessl, A., Tiberio, A., Vannuccini, E., Wada, T., Xiao, M., Yamatani, M., Yoshida, A., Yoshida, T., Zampa, G., and Zweerink, J.

Published
2021
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5. Δ9-THC Disrupts Gamma (γ)-Band Neural Oscillations in Humans

Author

Cortes-Briones, J, Skosnik, PD, Mathalon, D, Cahill, J, Pittman, B, Williams, A, Sewell, RA, Ranganathan, M, Roach, B, Ford, J, and D'Souza, DC

Subjects
Medical and Health Sciences, Psychology and Cognitive Sciences, Psychiatry
Abstract

Gamma (γ)-band oscillations play a key role in perception, associative learning, and conscious awareness and have been shown to be disrupted by cannabinoids in animal studies. The goal of this study was to determine whether cannabinoids disrupt γ-oscillations in humans and whether these effects relate to their psychosis-relevant behavioral effects. The acute, dose-related effects of Δ-9-tetrahydrocannabinol (Δ9-THC) on the auditory steady-state response (ASSR) were studied in humans (n=20) who completed 3 test days during which they received intravenous Δ9-THC (placebo, 0.015, and 0.03 mg/kg) in a double-blind, randomized, crossover, and counterbalanced design. Electroencephalography (EEG) was recorded while subjects listened to auditory click trains presented at 20, 30, and 40 Hz. Psychosis-relevant effects were measured with the Positive and Negative Syndrome scale (PANSS). Δ9-THC (0.03 mg/kg) reduced intertrial coherence (ITC) in the 40 Hz condition compared with 0.015 mg/kg and placebo. No significant effects were detected for 30 and 20 Hz stimulation. Furthermore, there was a negative correlation between 40 Hz ITC and PANSS subscales and total scores under the influence of Δ9-THC. Δ9-THC (0.03 mg/kg) reduced evoked power during 40 Hz stimulation at a trend level. Recent users of cannabis showed blunted Δ9-THC effects on ITC and evoked power. We show for the first time in humans that cannabinoids disrupt γ-band neural oscillations. Furthermore, there is a relationship between disruption of γ-band neural oscillations and psychosis-relevant phenomena induced by cannabinoids. These findings add to a growing literature suggesting some overlap between the acute effects of cannabinoids and the behavioral and psychophysiological alterations observed in psychotic disorders.

Published
2015

6. The self-concept as a bounding on occupational choice in young with problematic substance abuse and law offense history. Systematic review

Author

Lucía de la Quintana R., Olivia Grob L., Maureen Mac-Ginty F., Jeffrey Roach B., Macarena Vallejos C., and María Elena Riveros E.

Subjects
Industrial medicine. Industrial hygiene, RC963-969, Industrial hygiene. Industrial welfare, HD7260-7780.8
Abstract

This article aims to delve into the social stigma associated with being young with problematic substance abuse and law offense, and its direct implications in the process of building self-concept and occupational choice. To approach this issue, we developed a systematic literature review, in order to clarify whether self-concept acts as a limitation on occupational choice on this population. To develop this research we included thirty five articles, in which relationships between keywords were established. Although it was not possible to find literature to directly answer our initial research proposal, through the articulation of the results, we were able to confirm the supossed raised.

Published
2017
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12. In Search of Cosmic-Ray Antinuclei from Dark Matter with the GAPS Experiment

Author

Xiao, M., Aramaki, T., Bird, R., Boezio, M., Boggs, S. E., Bonvicini, V., Campana, D., Craig, W. W., Everson, E., Fabris, L., Fuke, H., Gahbauer, F., Garcia, I., Gerrity, C., Hailey, C. J., Hayashi, T., Kato, C., Kawachi, A., Kobayashi, S., Kozai, M., Lenni, A., Lowell, A., Manghisoni, Massimo, Marcelli, N., Mochizuki, B., Mognet, S. A. I., Munakata, K., Munini, R., Nakagami, Y., Olson, J., Ong, R. A., Osteria, G., Perez, K., Quinn, S., Re, Valerio, Riceputi, Elisa, Roach, B., Rogers, F., Ryan, J. A., Saffold, N., Scotti, V., Shimizu, Y., Sonzogni, M., Sparvoli, R., Stoessl, A., Tiberio, A., Vannuccini, E., von Doetinchem, P., Wada, T., Yamatami, M., Yoshida, A., Yoshida, T., Zampa, G., and Zweerink, J.

Subjects
Dark matter, readout electronics, Astroparticle physics, detectors, Settore ING-INF/01 - Elettronica
Published
2022

13. The GAPS Instrument: A Large Area Time of Flight and High Resolution Exotic Atom Spectrometer for Cosmic Antinuclei

Author

Quinn, S., Aramaki, T., Bird, R., Boezio, M., Boggs, S. E., Bonvicini, V., Campana, D., Craig, W. W., Everson, E., Fabris, L., Fuke, H., Gahbauer, F., Garcia, I., Gerrity, C., Hailey, C. J., Hayashi, T., Kato, C., Kawachi, A., Kobayashi, S., Kozai, M., Lenni, A., Lowell, A., Manghisoni, Massimo, Marcelli, N., Martucci, M., Mognet, S. I., Munakata, K., Munini, R., Nakagami, Y., Okazaki, S., Olson, J., Ong, R. A., Osteria, G., Perez, K., Re, Valerio, Riceputi, Elisa, Roach, B., Rogers, F., Ryan, J. A., Saffold, N., Saijo, M., Scotti, V., Shimizu, Y., Sonzogni, M., Sparvoli, R., Stoessl, A., Tokunaga, K., Vannuccini, E., von Doetinchem, P., Wada, T., Xiao, M., Yoshida, A., Yoshida, T., Zampa, G., and Zweerink, J.

Subjects
Settore ING-INF/01 - Elettronica
Published
2022

14. Neural Networks approach to event reconstruction for the GAPS experiment

Author

Marcelli, N., Aramaki, T., Bird, R., Boezio, M., Boggs, S. E., Bonvicini, V., Campana, D., Craig, W. W., Everson, E., Fabris, L., Fuke, H., Gahbauer, F., Garcia, I., Gerrity, C., Hailey, C. J., Hayashi, T., Kato, C., Kawachi, A., Kobayashi, S., Kozai, M., Lenni, A., Lowell, A., Manghisoni, Massimo, Mochizuki, B., Mognet, S. A. I., Munakata, K., Munini, R., Nakagami, Y., Olson, J., Ong, R. A., Osteria, G., Perez, K., Quinn, S., Re, Valerio, Riceputi, Elisa, Roach, B., Rogers, F., Ryan, J. A., Saffold, N., Scotti, V., Shimizu, Y., Sonzogni, M., Sparvoli, R., Stoessl, A., Tiberio, A., Vannuccini, E., von Doetinchem, P., Wada, T., Xiao, M., Yamatami, M., Yoshida, A., Yoshida, T., Zampa, G., and Zweerink, J.

Subjects
Settore ING-INF/01 - Elettronica
Published
2022

16. Search for Dark Matter signatures from cosmic-ray antinuclei with the GAPS experiment

Author

Tiberio, Alessio, primary, Aramaki, T., additional, Bird, R., additional, Boezio, M., additional, Boggs, S. E., additional, Bonvicini, V., additional, Campana, D., additional, Craig, W. W., additional, Everson, E., additional, Fabris, L., additional, Fuke, H., additional, Gahbauer, F., additional, Garcia, I., additional, Gerrity, C., additional, Hailey, C. J., additional, Hayashi, T., additional, Kato, C., additional, Kawachi, A., additional, Kobayashi, S., additional, Kozai, M., additional, Lenni, A., additional, Lowell, A., additional, Manghisoni, M., additional, Marcelli, N., additional, Mochizuki, B., additional, Mognet, S. I., additional, Munakata, K., additional, Munini, R., additional, Nakagami, Y., additional, Olson, J., additional, Ong, R. A., additional, Osteria, G., additional, Perez, K., additional, Quinn, S., additional, Re, V., additional, Riceputi, E., additional, Roach, B., additional, Rogers, F., additional, Ryan, J. A., additional, Saffold, N., additional, Scotti, V., additional, Shimizu, Y., additional, Sonzogni, M., additional, Sparvoli, R., additional, Stoessl, A., additional, Vannuccini, E., additional, von Doetinchem, P., additional, Wada, T., additional, Xiao, M., additional, Yamatami, M., additional, Yoshida, A., additional, Yoshida, T., additional, Zampa, G., additional, and Zweerink, J., additional

Published
2022
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17. Searching for cosmic antihelium nuclei with the GAPS experiment

Author

Stoessl, A., Aramaki, T., Bird, R., Boezio, M., Boggs, S. E., Bonvicini, V., Campana, D., Craig, W. W., Everson, E., Fabris, L., Fuke, H., Gahbauer, F., Garcia, I., Gerrity, C., Hailey, C. J., Hayashi, T., Kato, C., Kawachi, A., Kobayashi, S., Kozai, M., Lenni, A., Lowell, A., Manghisoni, Massimo, Marcelli, N., Mognet, S. A. I., Munakata, K., Munini, R., Nakagami, Y., Olson, J., Ong, R. A., Osteria, G., Perez, K., Quinn, S., Re, Valerio, Riceputi, Elisa, Roach, B., Rogers, F., Ryan, J. A., Saffold, N., Scotti, V., Shimizu, Y., Sonzogni, M., Sparvoli, R., Tiberio, A., Vannuccini, E., von Doetinchem, P., Wada, T., Xiao, M., Yamatami, M., Yoshida, A., Yoshida, T., Zampa, G., Zweerink, J., Aramaki, T., Bird, R., Boezio, M., Boggs, S. E., Bonvicini, V., Campana, D., Craig, W. W., Everson, E., Fabris, L., Fuke, H., Gahbauer, F., Garcia, I., Gerrity, C., Hailey, C. J., Hayashi, T., Kato, C., Kawachi, A., Kobayashi, S., Kozai, M., Lenni, A., Lowell, A., Manghisoni, M., Marcelli, N., Mochizuki, B., Mognet, S. A. I., Munakata, K., Munini, R., Nakagami, Y., Olson, J., Ong, R. A., Osteria, G., Perez, K., Quinn, S., Re, V., Riceputi, E., Roach, B., Rogers, F., Ryan, J. A., Saffold, N., Scotti, V., Shimizu, Y., Sonzogni, M., Sparvoli, R., Stoessl, A., Tiberio, A., Vannuccini, E., von Doetinchem, P., Wada, T., Xiao, M., Yamatani, M., Yoshida, A., Yoshida, T., Zampa, G., and Zweerink, J.

Subjects
Astroparticle Physics, cosmic rays, Readout electronics, Dark matter, Detectors, GAPS, cosmic antihelium, Settore ING-INF/01 - Elettronica, cosmic ray
Abstract

At low energies, cosmic antideuterons and antihelium provide an ultra-low background signature of dark matter annihilation, decay, and other beyond the Standard Model phenomena. The General Antiparticle Spectrometer (GAPS) is an Antarctic balloon experiment designed to search for lowenergy (0.1−0.3 GeV/n) antinuclei, and is planned to launch in the austral summer of 2022. While optimized for an antideuteron search, GAPS also has unprecedented capabilites for the detection of low-energy antihelium nuclei, utilizing a novel detection technique based on the formation, decay, and annihilation of exotic atoms. The AMS-02 collaboration has recently reported several antihelium nuclei candidate events, which sets GAPS in a unique position to set constraints on the cosmic antihelium flux in an energy region which is essentially free of astrophysical background. In this contribution, we illustrate the capabilities of GAPS to search for cosmic antihelium-3 utilizing complete instrument simulations, event reconstruction, and the inclusion of atmospheric effects. We show that GAPS is capable of setting unprecedented limits on the cosmic antihelium flux, opening a new window on exotic cosmic physics.

Published
2021

18. Neural Networks approach to event reconstruction for the GAPS experiment

Author

Aramaki, T., Bird, R., Boezio, M., Boggs, S. E., Bonvicini, V., Campana, D., Craig, W. W., Everson, E., Fabris, L., Fuke, H., Gahbauer, F., Garcia, I., Gerrity, C., Hailey, C. J., Hayashi, T., Kato, C., Kawachi, A., Kobayashi, S., Kozai, M., Lenni, A., Lowell, A., Manghisoni, M., Marcelli, N., Mochizuki, B., Mognet, S. A. I., Munakata, K., Munini, R., Nakagami, Y., Olson, J., Ong, R. A., Osteria, G., Perez, K., Quinn, S., Re, V., Riceputi, E., Roach, B., Rogers, F., Ryan, J. A., Saffold, N., Scotti, V., Shimizu, Y., Sonzogni, M., Sparvoli, R., Stoessl, A., Tiberio, A., Vannuccini, E., von Doetinchem, P., Wada, T., Xiao, M., Yamatani, M., Yoshida, A., Yoshida, T., Zampa, G., Zweerink, J., Aramaki, T., Bird, R., Boezio, M., Boggs, S. E., Bonvicini, V., Campana, D., Craig, W. W., Everson, E., Fabris, L., Fuke, H., Gahbauer, F., Garcia, I., Gerrity, C., Hailey, C. J., Hayashi, T., Kato, C., Kawachi, A., Kobayashi, S., Kozai, M., Lenni, A., Lowell, A., Manghisoni, M., Marcelli, N., Mochizuki, B., Mognet, S. A. I., Munakata, K., Munini, R., Nakagami, Y., Olson, J., Ong, R. A., Osteria, G., Perez, K., Quinn, S., Re, V., Riceputi, E., Roach, B., Rogers, F., Ryan, J. A., Saffold, N., Scotti, V., Shimizu, Y., Sonzogni, M., Sparvoli, R., Stoessl, A., Tiberio, A., Vannuccini, E., von Doetinchem, P., Wada, T., Xiao, M., Yamatani, M., Yoshida, A., Yoshida, T., Zampa, G., and Zweerink, J.

Subjects
GAPS, neural networks, event reconstruction, neural network
Abstract

The General Antiparticle Spectrometer (GAPS) is a balloon-borne experiment, scheduled for a first flight in the austral summer 2022. It is designed to measure low energy (< 0.25 GeV/n) cosmic antinuclei. A particular focus is on antideuterons, which are predicted to have an ultra-low astrophysical background as compared to signals from dark matter annihilation or decay in the Galactic halo. GAPS uses a novel technique for particle identification based on the formation and decay of exotic atoms. To achieve sufficient rejection power for particle identification, an accurate determination of several fundamental quantities is needed. The precise reconstruction of the energy deposition pattern on the primary track is a particularly intricate problem and we developed a strategy devised to solve this using modern machine learning techniques. In the future, this approach can also be used for particle identification. Here, we present preliminary results of these efforts obtained from simulations.

Published
2021

20. Cosmic Antiproton Sensitivity for the GAPS Experiment

Author

Rogers, Field, primary, Aramaki, T, additional, Bird, R, additional, Aramaki, T., additional, Bird, R., additional, Boezio, M., additional, Boggs, S. E., additional, Bonvicini, V., additional, Campana, D., additional, Craig, W. W., additional, Everson, E., additional, Fabris, L., additional, Fuke, H., additional, Gahbauer, F., additional, Garcia, I., additional, Gerrity, C., additional, Hailey, C. J., additional, Hayashi, T., additional, Kato, C., additional, Kawachi, A., additional, Kobayashi, S., additional, Kozai, M., additional, Lenni, A., additional, Lowell, A., additional, Manghisoni, M., additional, Marcelli, N., additional, Mochizuki, B., additional, Mognet, S. A. I., additional, Munakata, K., additional, Munini, R., additional, Nakagami, Y., additional, Olson, J., additional, Ong, R. A., additional, Osteria, G., additional, Perez, K., additional, Quinn, S., additional, Re, V., additional, Riceputi, E., additional, Roach, B., additional, Ryan, J. A., additional, Saffold, N., additional, Scotti, V., additional, Shimizu, Y., additional, Sonzogni, M., additional, Sparvoli, R., additional, Stoessl, A., additional, Tiberio, A., additional, Vannuccini, E., additional, von Doetinchem, P., additional, Wada, T., additional, Xiao, M., additional, Yamatani, M., additional, Yoshida, A., additional, Yoshida, T., additional, Zampa, G., additional, and Zweerink, J., additional

Published
2021
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21. Reconstruction of antinucleus-annihilation events in the GAPS experiment

Author

Tiberio, Alessio, primary, Aramaki, T., additional, Bird, R., additional, Boezio, M., additional, Boggs, S. E., additional, Bonvicini, V., additional, Campana, D., additional, Craig, W. W., additional, Everson, E., additional, Fabris, L., additional, Fuke, H., additional, Gahbauer, F., additional, Garcia, I., additional, Gerrity, C., additional, Hailey, C. J., additional, Hayashi, T., additional, Kato, C., additional, Kawachi, A., additional, Kobayashi, S., additional, Kozai, M., additional, Lenni, A., additional, Lowell, A., additional, Manghisoni, M., additional, Marcelli, N., additional, Mochizuki, B., additional, Mognet, S. I., additional, Munakata, K., additional, Munini, R., additional, Nakagami, Y., additional, Olson, J., additional, Ong, R. A., additional, Osteria, G., additional, Perez, K., additional, Quinn, S., additional, Re, V., additional, Riceputi, E., additional, Roach, B., additional, Rogers, F., additional, Ryan, J. A., additional, Saffold, N., additional, Scotti, V., additional, Shimizu, Y., additional, Sonzogni, M., additional, Sparvoli, R., additional, Stoessl, A., additional, Vannuccini, E., additional, von Doetinchem, P., additional, Wada, T., additional, Xiao, M., additional, Yamatami, M., additional, Yoshida, A., additional, Yoshida, T., additional, Zampa, G., additional, and Zweerink, J., additional

Published
2021
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25. Evidence of Slow Neural Processing, Developmental Differences and Sensitivity to Cannabis Effects in a Sample at Clinical High Risk for Psychosis From the NAPLS Consortium Assessed With the Human Startle Paradigm

Author

Duncan, E., Roach, B., Bearden, C., Addington, J., Light, G., Walker, E.F., Johannesen, J., Carri��n, R.E., Mathalon, D., Nunag, J., Cadenhead, K.S., Cannon, T.D., Tsuang, M., Woods, S.W., Perkins, D.O., Seidman, L.J., Cornblatt, B.A., Niznikiewicz, M., Bauchman, P., McGlashan, T.H., Belger, A., North American Prodromal Longitudinal Studies Consortium, and Donkers, F.

Abstract

Biomarkers are important in the study of the prodromal period of psychosis because they can help to identify individuals at greatest risk for future psychotic illness and provide insights into disease mechanism underlying neurodevelopmental abnormalities. The biomarker abnormalities can then be targeted with treatment, with an aim toward prevention or mitigation of disease. The human startle paradigm has been used in translational studies of psychopathology including psychotic illness to assess preattentive information processing for over 50 years. In one of the largest studies to date in clinical high risk (CHR) for psychosis participants, we aimed to evaluate startle indices as biomarkers of risk along with the role of age, sex, treatment, and substance use in this population of high risk individuals. Methods: Startle response reactivity, latency, and prepulse inhibition (PPI) were assessed in 543 CHR and 218 Normal Comparison (NC) participants between the ages of 12 and 35. Results: At 1 year follow-up, 58 CHR participants had converted to psychosis. CHR and NC groups did not differ across any of the startle measures but those CHR participants who later converted to psychosis had significantly slower startle latency than did those who did not convert to psychosis, and this effect was driven by female CHR participants. PPI was significantly associated with age in the CHR, but not the NC, participants with the greatest positive age correlations present in those CHR participants who later converted to psychosis, consistent with a prior report. Finally, there was a significant group by cannabis use interaction due to greater PPI in cannabis users and opposite PPI group effects in users (CHR>NC) and non-users (NC>CHR). Discussion: This is the first study to demonstrate a relationship of startle response latency to psychotic conversion in a CHR population. PPI is an important biomarker that may be sensitive to the neurodevelopmental abnormalities thought to be present in psychosis prone individuals and the effects of cannabis. The significant correlations with age in this sample as well as the finding of greater PPI in CHR cannabis users replicate findings from another large sample of CHR participants.

Published
2020
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33. A275 DONOR BODY MASS INDEX (BMI) DOES NOT IMPACT RECIPIENT BMI FOLLOWING FECAL MICROBIOTA TRANSPLANTATION FOR RECURRENT CLOSTRIDIUM DIFFICILE INFECTION

Author

Smith, J D, Roach, B, Hassanzadeh Keshteli, A, and Kao, D H

Subjects
Poster Presentations
Abstract

BACKGROUND: Fecal microbiota transplantation (FMT), which restores gut dysbiosis, is an effective treatment option for recurrent Clostridium difficile infection (RCDI). Although there are guidelines for stool donor screening to minimize risk of disease transmitted by stool, there are no recommendations on donor BMI. Obesity, a condition associated with intestinal dysbiosis, can be transferred by FMT in the mouse model. Further, there is a case report of a woman who developed new-onset obesity after receiving stool from a healthy but overweight donor. However, it remains unknown whether stool donor BMI has any significant impact on recipient BMI after FMT in RCDI. AIMS: The aim of this study was to determine the impact of stool donor BMI on recipient BMI in RCDI. METHODS: Forty-six patients with RCDI were randomized to receiving FMT by colonoscopy or by capsules (1:1) from one of three different volunteer donors registered with the Edmonton FMT Program. The donors are healthy and between the ages of 32–45, with BMIs of 18.3 kg/m(2), 24.9 kg/m(2), and 30 kg/m(2). Pre-FMT weight and height were measured at screening visit, and weight was measured 1 week, 4 weeks and 12 weeks post-FMT. Weight lost during RCDI was recorded to calculate baseline BMI. Statistical measures were used to determine trends in weight loss from RCDI, changes in BMI over time, and effects of donor and method of FMT delivery on recipient BMI. RESULTS: There were no significant differences between participant baseline characteristics. The mean reported weight loss from RCDI was 5.44 ± 4.34 kg in the capsules arm and 3.72 ± 4.73 kg in the colonoscopy arm (p = 0.89). Participant BMI was significantly lower at time of FMT delivery when compared to reported baseline BMI (p < 0.05). Compared to BMI at baseline, BMI at week 12 was not significantly different, irrespective of donor or treatment method (Fig. 1). Fourteen patients (30%) gained weight 12 weeks post-FMT compared to baseline, but the difference was not statistically significant; furthermore, this observation was not donor or FMT method dependent. CONCLUSIONS: Our study highlighted the trends in weight recovery in RCDI patients after receiving FMT. Most patients regained weight lost during RCDI by week 12, irrespective of donor BMI or method of FMT delivery. For those patients who gained weight after FMT, the difference was not significant, and was not dependent of stool donor or FMT treatment modality. FUNDING AGENCIES: University of Alberta Hospital Foundation

Published
2018

36. Use model predictive control to achieve real-time management of a DWC

Author

Blevins, T., Downs, J., Donahue, M., and Roach, B.

Subjects
Energy industry -- Finance, Savings -- Management, Company business management, Company financing, Business, Petroleum, energy and mining industries
Abstract

Byline: Blevins, T. ,Downs, J. ,Donahue, M. ,Roach, B. A dividing-wall column (DWC) can provide significant savings in energy and capital cost compared to a conventional distillation column design. However, [...]

Published
2015

38. Resting-state thalamic dysconnectivity in schizophrenia and relationships with symptoms

Author

Ferri, J., primary, Ford, J. M., additional, Roach, B. J., additional, Turner, J. A., additional, van Erp, T. G., additional, Voyvodic, J., additional, Preda, A., additional, Belger, A., additional, Bustillo, J., additional, O'Leary, D., additional, Mueller, B. A., additional, Lim, K. O., additional, McEwen, S. C., additional, Calhoun, V. D., additional, Diaz, M., additional, Glover, G., additional, Greve, D., additional, Wible, C. G., additional, Vaidya, J. G., additional, Potkin, S. G., additional, and Mathalon, D. H., additional

Published
2018
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46. Balloon Cell Urethral Melanoma: Differential Diagnosis and Management

Author

McComiskey, M., Iavazzo, C., Datta, M., Slade, R., Winter-Roach, B., Lambe, G., Sangar, V. K., and Smith, M.

Subjects
Article Subject
Abstract

Introduction. Primary malignant melanoma of the urethra is a rare tumour (0.2% of all melanomas) that most commonly affects the meatus and distal urethra and is three times more common in women than men. Case. A 76-year-old lady presented with vaginal pain and discharge. On examination, a 4 cm mass was noted in the vagina and biopsy confirmed melanoma of a balloon type. Preoperative CT showed no distant metastases and an MRI scan of the pelvis demonstrated no associated lymphadenopathy. She underwent anterior exenterative surgery and vaginectomy also. Histology confirmed a urethral nodular malignant melanoma. Discussion. First-line treatment of melanoma is often surgical. Adjuvant treatment including chemotherapy, radiotherapy, or immunotherapy has also been reported. Even with aggressive management, malignant melanoma of the urogenital tract generally has a poor prognosis. Recurrence rates are high and the mean period between diagnosis and recurrence is 12.5 months. A 5-year survival rate of less than 20% has been reported in balloon cell melanomas along with nearly 20% developing local recurrence. Conclusion. To the best of our knowledge, this case is the first report of balloon cell melanoma arising in the urethra. The presentation and surgical management has been described and a literature review provided.

Published
2015
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