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1. Seymour Falls, possibly Oxford or Beacon Falls.

Author

Storrs, J. W. and Storrs, J. W.

Subjects
Industrial buildings., Waterfalls., Constructions industrielles., industrial buildings., Industrial buildings., Waterfalls., Beacon Falls (Conn.), Oxford (Conn.), Connecticut Oxford.
Abstract

A stone factory building with a cupola is situated in a rocky gorge beside a stream and waterfall. Additional buildings, one with a smokestack, are on the far bank. Leafless tree branches are at the right.

Published
2024

2. Overview of recent physics results from MAST

Author

Kirk, A, Adamek, J, Akers, RJ, Allan, S, Appel, L, Lucini, F Arese, Barnes, M, Barrett, T, Ayed, N Ben, Boeglin, W, Bradley, J, Browning, P K, Brunner, J, Cahyna, P, Carr, M, Casson, F, Cecconello, M, Challis, C, Chapman, IT, Chapman, S, Conroy, S, Conway, N, Cooper, WA, Cox, M, Crocker, N, Crowley, B, Cardnell, S, Chorley, J, Cunningham, G, Danilov, A, Darrow, D, Dendy, R, Dickinson, D, Dorland, W, Dudson, B, Easy, L, Elmore, S, Evans, M, Farley, T, Fedorczak, N, Field, A, Fitzgerald, I, Fox, M, Freethy, S, Garzotti, L, Ghim, YC, Gi, K, Gorelenkova, M, Gracias, W, Gurl, C, Guttenfelder, W, Ham, C, Harting, D, Havlickova, E, Hawkes, N, Hender, T, Henderson, S, Hillesheim, J, Hnat, B, Horacek, J, Howard, J, Howell, D, Dunai, D, Fishpool, G, Gibson, K, Harrison, J, Highcock, E, Huang, B, Inomoto, M, Imazawa, R, Jones, O, Kadowaki, K, Kaye, S, Keeling, D, Kocan, M, Kogan, L, Komm, M, Lai, W, Leddy, J, Leggate, H, Imada, K, Klimek, I, Hollocombe, J, Lipschultz, B, Lisgo, S, Liu, YQ, Lloyd, B, Lomanowski, B, Lukin, V, Maddison, G, Madsen, J, Mailloux, J, Martin, R, McArdle, G, Lupelli, I, McClements, K, McMillan, B, Meakins, A, Meyer, H, Michael, C, Militello, F, Milnes, J, Motojima, G, Muir, D, Naylor, G, Nielsen, A, O'Brien, M, O'Mullane, M, Olsen, J, Omotani, J, Ono, Y, Pamela, S, Morris, AW, O'Gorman, T, Pangione, L, Parra, F, Patel, A, Peebles, W, Perez, R, Pinches, S, Piron, L, Price, M, Reinke, M, Ricci, P, Riva, F, Roach, C, Romanelli, M, Ryan, D, Saarelma, S, Saveliev, A, Scannell, R, Schekochihin, A, Sharapov, S, Sharples, R, Shevchenko, V, Shinohara, K, Silburn, S, Simpson, J, Stanier, A, Storrs, J, Summers, H, Takase, Y, Tamain, P, Tanabe, H, Tanaka, H, Tani, K, Taylor, D, Thomas, D, Thomas-Davies, N, Thornton, A, Turnyanskiy, M, Valovic, M, Vann, R, Van Wyk, F, Walkden, N, Watanabe, T, Wilson, H, Wischmeier, M, Yamada, T, Young, J, Zoletnik, S, Team, the MAST, and Team, the EUROfusion MST1

Subjects
Physics - Plasma Physics
Abstract

New results from MAST are presented that focus on validating models in order to extrapolate to future devices. Measurements during start-up experiments have shown how the bulk ion temperature rise scales with the square of the reconnecting field. During the current ramp up models are not able to correctly predict the current diffusion. Experiments have been performed looking at edge and core turbulence. At the edge detailed studies have revealed how filament characteristic are responsible for determining the near and far SOL density profiles. In the core the intrinsic rotation and electron scale turbulence have been measured. The role that the fast ion gradient has on redistributing fast ions through fishbone modes has led to a redesign of the neutral beam injector on MAST Upgrade. In H-mode the turbulence at the pedestal top has been shown to be consistent with being due to electron temperature gradient modes. A reconnection process appears to occur during ELMs and the number of filaments released determines the power profile at the divertor. Resonant magnetic perturbations can mitigate ELMs provided the edge peeling response is maximised and the core kink response minimised. The mitigation of intrinsic error fields with toroidal mode number n>1 has been shown to be important for plasma performance., Comment: 34 pages, 10 figures. This is an author-created, un-copyedited version of an article submitted for publication in Nuclear Fusion. IoP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it

Published
2016
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3. New magnetic real time shape control for MAST

Author

Pangione, L, McArdle, G, and Storrs, J

Subjects
Physics - Plasma Physics
Abstract

The MAST (Mega Ampere Spherical Tokamak) real time plasma position controller is based on an optical linear camera placed on the mid plane of the vessel. This solution has the advantage of being a direct observation of the D [alpha]emissions coming from the interaction between the boundary of the plasma and neutral gas, but, on the other hand, it restricts the control to the outer radius of the plasma only. A complete chain of tools has been set up to implement, test and simulate a new real time magnetic plasma shape controller based on the rtEFIT code. The complete working path consists of three elements: a linear static relationship between control parameters and current demands, a linear state space model needed to represent the plasma dynamic response in closed loop simulations, and the possibility to run simulations inside the Plasma Control System (PCS). The linear relationship has been calculated using the FIESTA code, which is developed using Matlab at CCFE. The linear state space model was generated using the CREATE-L code developed by the CREATE Consortium. It has already been successfully used to model JET, FTU and TCV tokamaks. Using this working path many simulations have been carried out allowing fine tuning of the control gains before the real experiment. The simulation testing includes the plasma shape control law as implemented in PCS itself, so intensive debugging has been possible prior to operation. Successful control using rtEFIT was established in the second dedicated experiment during the MAST 2011-12 campaign. This work is a stepping stone towards divertor control which is ultimately intended for application to the super-X divertor in the MAST Upgrade experiment., Comment: 5 pages, 5 figures

Published
2013
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12. Overview of recent physics results from MAST

Author

Andrew, Kirk, Adamek, J, Akers, Rj, Allan, S, Appel, L, F Arese Lucini, Barnes, M, Barrett, T, N Ben Ayed, Boeglin, W, Bradley, J, Browning, Pk, Brunner, J, Cahyna, P, Cardnell, S, Meghan, Carr, Casson, Federica, Marco, Cecconello, Challis, C, Chapman, It, Chapman, S, Chorley, J, Sean, Conroy, Conway, N, Cooper, Wa, Cox, M, Crocker, N, Crowley, B, Cunningham, G, Danilov, A, Darrow, D, Dendy, R, Dickinson, D, Dorland, W, Dudson, B, Dunai, D, Easy, L, Elmore, S, Evans, KAREN MARILYN, Farley, T, Fedorczak, N, Field, A, Fishpool, G, Fitzgerald, I, Fox, M, Freethy, S, Garzotti, L, Ghim, Yc, K, Gi, Gibson, K, Gorelenkova, M, Gracias, W, Gurl, C, Guttenfelder, W, Ham, C, Harrison, J, Harting, D, Havlickova, E, Hawkes, N, Hender, T, Henderson, S, Highcock, E, Hillesheim, J, Hnat, B, Horacek, J, Zehr, HOWARD JAY, Howell, D, Huang, B, Imada, K, Inomoto, M, Imazawa, R, Jones, O, Kadowaki, K, Kaye, S, Keeling, D, Iwona, Klimek, Kocan, M, Kogan, L, Komm, M, Lai, W, Leddy, J, Leggate, H, Hollocombe, J, Lipschultz, B, Lisgo, S, Liu, Yq, Lloyd, B, Lomanowski, B, Lukin, V, Lupelli, I, Maddison, G, Jens, Madsen, Mailloux, J, Martin, R, Mcardle, G, Mcclements, K, Mcmillan, B, Meakins, A, Meyer, H, Michael, C, Militello, F, Milnes, J, Morris, Aw, Motojima, G, Derek, Muir, Naylor, G, Nielsen, A, O’Brien, M, O’Gorman, T, O’Mullane, M, Olsen, J, Omotani, J, Ono, Y, Pamela, S, Pangione, L, Parra, F, Patel, A, Peebles, W, ALVAREZ PEREZ, PEDRO RICCARDO, Pinches, S, Piron, L, Price, ALEXANDER MARCUS, Reinke, M, Ricci, P, Riva, F, Roach, C, Romanelli, M, Ryan, D, Saarelma, S, Saveliev, A, Scannell, R, Schekochihin, A, Sharapov, S, Sharples, R, Shevchenko, V, Shinohara, K, Silburn, S, Simpson, J, Stanier, A, Storrs, J, Summers, H, Takase, Y, Tamain, P, Tanabe, H, Tanaka, H, Tani, K, WILLIAMSON TAYLOR, DEBIE CLAUDIA, Thomas, DEEPA ROSE, Thomas-Davies, N, and Thornton, A

Published
2017

13. Overview of recent physics results from MAST

Author

Kirk, A., primary, Adamek, J., additional, Akers, R.J., additional, Allan, S., additional, Appel, L., additional, Arese Lucini, F., additional, Barnes, M., additional, Barrett, T., additional, Ben Ayed, N., additional, Boeglin, W., additional, Bradley, J., additional, Browning, P.K., additional, Brunner, J., additional, Cahyna, P., additional, Cardnell, S., additional, Carr, M., additional, Casson, F., additional, Cecconello, M., additional, Challis, C., additional, Chapman, I.T., additional, Chapman, S., additional, Chorley, J., additional, Conroy, S., additional, Conway, N., additional, Cooper, W.A., additional, Cox, M., additional, Crocker, N., additional, Crowley, B., additional, Cunningham, G., additional, Danilov, A., additional, Darrow, D., additional, Dendy, R., additional, Dickinson, D., additional, Dorland, W., additional, Dudson, B., additional, Dunai, D., additional, Easy, L., additional, Elmore, S., additional, Evans, M., additional, Farley, T., additional, Fedorczak, N., additional, Field, A., additional, Fishpool, G., additional, Fitzgerald, I., additional, Fox, M., additional, Freethy, S., additional, Garzotti, L., additional, Ghim, Y.C., additional, Gi, K., additional, Gibson, K., additional, Gorelenkova, M., additional, Gracias, W., additional, Gurl, C., additional, Guttenfelder, W., additional, Ham, C., additional, Harrison, J., additional, Harting, D., additional, Havlickova, E., additional, Hawkes, N., additional, Hender, T., additional, Henderson, S., additional, Highcock, E., additional, Hillesheim, J., additional, Hnat, B., additional, Horacek, J., additional, Howard, J., additional, Howell, D., additional, Huang, B., additional, Imada, K., additional, Inomoto, M., additional, Imazawa, R., additional, Jones, O., additional, Kadowaki, K., additional, Kaye, S., additional, Keeling, D., additional, Klimek, I., additional, Kocan, M., additional, Kogan, L., additional, Komm, M., additional, Lai, W., additional, Leddy, J., additional, Leggate, H., additional, Hollocombe, J., additional, Lipschultz, B., additional, Lisgo, S., additional, Liu, Y.Q., additional, Lloyd, B., additional, Lomanowski, B., additional, Lukin, V., additional, Lupelli, I., additional, Maddison, G., additional, Madsen, J., additional, Mailloux, J., additional, Martin, R., additional, McArdle, G., additional, McClements, K., additional, McMillan, B., additional, Meakins, A., additional, Meyer, H., additional, Michael, C., additional, Militello, F., additional, Milnes, J., additional, Morris, A.W., additional, Motojima, G., additional, Muir, D., additional, Naylor, G., additional, Nielsen, A., additional, O’Brien, M., additional, O’Gorman, T., additional, O’Mullane, M., additional, Olsen, J., additional, Omotani, J., additional, Ono, Y., additional, Pamela, S., additional, Pangione, L., additional, Parra, F., additional, Patel, A., additional, Peebles, W., additional, Perez, R., additional, Pinches, S., additional, Piron, L., additional, Price, M., additional, Reinke, M., additional, Ricci, P., additional, Riva, F., additional, Roach, C., additional, Romanelli, M., additional, Ryan, D., additional, Saarelma, S., additional, Saveliev, A., additional, Scannell, R., additional, Schekochihin, A., additional, Sharapov, S., additional, Sharples, R., additional, Shevchenko, V., additional, Shinohara, K., additional, Silburn, S., additional, Simpson, J., additional, Stanier, A., additional, Storrs, J., additional, Summers, H., additional, Takase, Y., additional, Tamain, P., additional, Tanabe, H., additional, Tanaka, H., additional, Tani, K., additional, Taylor, D., additional, Thomas, D., additional, Thomas-Davies, N., additional, Thornton, A., additional, Turnyanskiy, M., additional, Valovic, M., additional, Vann, R., additional, Van Wyk, F., additional, Walkden, N., additional, Watanabe, T., additional, Wilson, H., additional, Wischmeier, M., additional, Yamada, T., additional, Young, J., additional, and Zoletnik, S., additional

Published
2017
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14. Overview of recent physics results from MAST

Author

Kirk, A., Adamek, J., Akers, R. J., Allan, S., Appel, L., Lucini, F. Arese, Barnes, M., Barrett, T., Ben Ayed, N., Boeglin, W., Bradley, J., Browning, P. K., Brunner, J., Cahyna, P., Cardnell, S., Carr, M., Casson, F., Cecconello, Marco, Challis, C., Chapman, I. T., Chapman, S., Chorley, J., Conroy, Sean, Conway, N., Cooper, W. A., Cox, M., Crocker, N., Crowley, B., Cunningham, G., Danilov, A., Darrow, D., Dendy, R., Dickinson, D., Dorland, W., Dudson, B., Dunai, D., Easy, L., Elmore, S., Evans, M., Farley, T., Fedorczak, N., Field, A., Fishpool, G., Fitzgerald, I., Fox, M., Freethy, S., Garzotti, L., Ghim, Y. C., Gi, K., Gibson, K., Gorelenkova, M., Gracias, W., Gurl, C., Guttenfelder, W., Ham, C., Harrison, J., Harting, D., Havlickova, E., Hawkes, N., Hender, T., Henderson, S., Highcock, E., Hillesheim, J., Hnat, B., Horacek, J., Howard, J., Howell, D., Huang, B., Imada, K., Inomoto, M., Imazawa, R., Jones, O., Kadowaki, K., Kaye, S., Keeling, D., Klimek, Iwona, Kocan, M., Kogan, L., Komm, M., Lai, W., Leddy, J., Leggate, H., Hollocombe, J., Lipschultz, B., Lisgo, S., Liu, Y. Q., Lloyd, B., Lomanowski, B., Lukin, V., Lupelli, I., Maddison, G., Madsen, J., Mailloux, J., Martin, R., McArdle, G., McClements, K., McMillan, B., Meakins, A., Meyer, H., Michael, C., Militello, F., Milnes, J., Morris, A. W., Motojima, G., Muir, D., Naylor, G., Nielsen, A., O'Brien, M., O'Gorman, T., O'Mullane, M., Olsen, J., Omotani, J., Ono, Y., Pamela, S., Pangione, L., Parra, F., Patel, A., Peebles, W., Perez, R., Pinches, S., Piron, L., Price, M., Reinke, M., Ricci, P., Riva, F., Roach, C., Romanelli, M., Ryan, D., Saarelma, S., Saveliev, A., Scannell, R., Schekochihin, A., Sharapov, S., Sharples, R., Shevchenko, V., Shinohara, K., Silburn, S., Simpson, J., Stanier, A., Storrs, J., Summers, H., Takase, Y., Tamain, P., Tanabe, H., Tanaka, H., Tani, K., Taylor, D., Thomas, D., Thomas-Davies, N., Thornton, A., Turnyanskiy, M., Valovic, M., Vann, R., Van Wyk, F., Walkden, N., Watanabe, T., Wilson, H., Wischmeier, M., Yamada, T., Young, J., Zoletnik, S., Kirk, A., Adamek, J., Akers, R. J., Allan, S., Appel, L., Lucini, F. Arese, Barnes, M., Barrett, T., Ben Ayed, N., Boeglin, W., Bradley, J., Browning, P. K., Brunner, J., Cahyna, P., Cardnell, S., Carr, M., Casson, F., Cecconello, Marco, Challis, C., Chapman, I. T., Chapman, S., Chorley, J., Conroy, Sean, Conway, N., Cooper, W. A., Cox, M., Crocker, N., Crowley, B., Cunningham, G., Danilov, A., Darrow, D., Dendy, R., Dickinson, D., Dorland, W., Dudson, B., Dunai, D., Easy, L., Elmore, S., Evans, M., Farley, T., Fedorczak, N., Field, A., Fishpool, G., Fitzgerald, I., Fox, M., Freethy, S., Garzotti, L., Ghim, Y. C., Gi, K., Gibson, K., Gorelenkova, M., Gracias, W., Gurl, C., Guttenfelder, W., Ham, C., Harrison, J., Harting, D., Havlickova, E., Hawkes, N., Hender, T., Henderson, S., Highcock, E., Hillesheim, J., Hnat, B., Horacek, J., Howard, J., Howell, D., Huang, B., Imada, K., Inomoto, M., Imazawa, R., Jones, O., Kadowaki, K., Kaye, S., Keeling, D., Klimek, Iwona, Kocan, M., Kogan, L., Komm, M., Lai, W., Leddy, J., Leggate, H., Hollocombe, J., Lipschultz, B., Lisgo, S., Liu, Y. Q., Lloyd, B., Lomanowski, B., Lukin, V., Lupelli, I., Maddison, G., Madsen, J., Mailloux, J., Martin, R., McArdle, G., McClements, K., McMillan, B., Meakins, A., Meyer, H., Michael, C., Militello, F., Milnes, J., Morris, A. W., Motojima, G., Muir, D., Naylor, G., Nielsen, A., O'Brien, M., O'Gorman, T., O'Mullane, M., Olsen, J., Omotani, J., Ono, Y., Pamela, S., Pangione, L., Parra, F., Patel, A., Peebles, W., Perez, R., Pinches, S., Piron, L., Price, M., Reinke, M., Ricci, P., Riva, F., Roach, C., Romanelli, M., Ryan, D., Saarelma, S., Saveliev, A., Scannell, R., Schekochihin, A., Sharapov, S., Sharples, R., Shevchenko, V., Shinohara, K., Silburn, S., Simpson, J., Stanier, A., Storrs, J., Summers, H., Takase, Y., Tamain, P., Tanabe, H., Tanaka, H., Tani, K., Taylor, D., Thomas, D., Thomas-Davies, N., Thornton, A., Turnyanskiy, M., Valovic, M., Vann, R., Van Wyk, F., Walkden, N., Watanabe, T., Wilson, H., Wischmeier, M., Yamada, T., Young, J., and Zoletnik, S.

Abstract

New results from MAST are presented that focus on validating models in order to extrapolate to future devices. Measurements during start-up experiments have shown how the bulk ion temperature rise scales with the square of the reconnecting field. During the current ramp-up, models are not able to correctly predict the current diffusion. Experiments have been performed looking at edge and core turbulence. At the edge, detailed studies have revealed how filament characteristics are responsible for determining the near and far scrape off layer density profiles. In the core the intrinsic rotation and electron scale turbulence have been measured. The role that the fast ion gradient has on redistributing fast ions through fishbone modes has led to a redesign of the neutral beam injector on MAST Upgrade. In H-mode the turbulence at the pedestal top has been shown to be consistent with being due to electron temperature gradient modes. A reconnection process appears to occur during edge localized modes (ELMs) and the number of filaments released determines the power profile at the divertor. Resonant magnetic perturbations can mitigate ELMs provided the edge peeling response is maximised and the core kink response minimised. The mitigation of intrinsic error fields with toroidal mode number n > 1 has been shown to be important for plasma performance.

Published
2017
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15. Overview of MAST results

Author

Chapman, I. T., Adamek, J., Akers, R. J., Allan, S., Appel, L., Asunta, O., Barnes, M., Ben Ayed, N., Bigelow, T., Boeglin, W., Bradley, J., Bruenner, J., Cahyna, P., Carr, M., Caughman, J., Cecconello, Marco, Challis, C., Chapman, S., Chorley, J., Colyer, G., Conway, N., Cooper, W. A., Cox, M., Crocker, N., Crowley, B., Cunningham, G., Danilov, A., Darrow, D., Dendy, R., Diallo, A., Dickinson, D., Diem, S., Dorland, W., Dudson, B., Dunai, D., Easy, L., Elmore, S., Field, A., Fishpool, G., Fox, M., Fredrickson, E., Freethy, S., Garzotti, L., Ghim, Y. C., Gibson, K., Graves, J., Gurl, C., Guttenfelder, W., Ham, C., Harrison, J., Harting, D., Havlickova, E., Hawke, J., Hawkes, N., Hender, T., Henderson, S., Highcock, E., Hillesheim, J., Hnat, B., Holgate, J., Horacek, J., Howard, J., Huang, B., Imada, K., Jones, O., Kaye, S., Keeling, D., Kirk, A., Klimek, Iwona, Kocan, M., Leggate, H., Lilley, M., Lipschultz, B., Lisgo, S., Liu, Y. Q., Lloyd, B., Lomanowski, B., Lupelli, I., Maddison, G., Mailloux, J., Martin, R., McArdle, G., McClements, K., McMillan, B., Meakins, A., Meyer, H., Michael, C., Militello, F., Milnes, J., Morris, A. W., Motojima, G., Muir, D., Nardon, E., Naulin, V., Naylor, G., Nielsen, A., O'Brien, M., O'Gorman, T., Ono, Y., Oliver, H., Pamela, S., Pangione, L., Parra, F., Patel, A., Peebles, W., Peng, M., Perez, R., Pinches, S., Piron, L., Podesta, M., Price, M., Reinke, M., Ren, Y., Roach, C., Robinson, J., Romanelli, M., Rozhansky, V., Saarelma, S., Sangaroon, Siriyaporn, Saveliev, A., Scannell, R., Schekochihin, A., Sharapov, S., Sharples, R., Shevchenko, V., Silburn, S., Simpson, J., Storrs, J., Takase, Y., Tanabe, H., Tanaka, H., Taylor, D., Taylor, G., Thomas, D., Thomas-Davies, N., Thornton, A., Turnyanskiy, M., Valovic, M., Vann, R., Walkden, N., Wilson, H., Wyk, L. V., Yamada, T., Zoletnik, S., Chapman, I. T., Adamek, J., Akers, R. J., Allan, S., Appel, L., Asunta, O., Barnes, M., Ben Ayed, N., Bigelow, T., Boeglin, W., Bradley, J., Bruenner, J., Cahyna, P., Carr, M., Caughman, J., Cecconello, Marco, Challis, C., Chapman, S., Chorley, J., Colyer, G., Conway, N., Cooper, W. A., Cox, M., Crocker, N., Crowley, B., Cunningham, G., Danilov, A., Darrow, D., Dendy, R., Diallo, A., Dickinson, D., Diem, S., Dorland, W., Dudson, B., Dunai, D., Easy, L., Elmore, S., Field, A., Fishpool, G., Fox, M., Fredrickson, E., Freethy, S., Garzotti, L., Ghim, Y. C., Gibson, K., Graves, J., Gurl, C., Guttenfelder, W., Ham, C., Harrison, J., Harting, D., Havlickova, E., Hawke, J., Hawkes, N., Hender, T., Henderson, S., Highcock, E., Hillesheim, J., Hnat, B., Holgate, J., Horacek, J., Howard, J., Huang, B., Imada, K., Jones, O., Kaye, S., Keeling, D., Kirk, A., Klimek, Iwona, Kocan, M., Leggate, H., Lilley, M., Lipschultz, B., Lisgo, S., Liu, Y. Q., Lloyd, B., Lomanowski, B., Lupelli, I., Maddison, G., Mailloux, J., Martin, R., McArdle, G., McClements, K., McMillan, B., Meakins, A., Meyer, H., Michael, C., Militello, F., Milnes, J., Morris, A. W., Motojima, G., Muir, D., Nardon, E., Naulin, V., Naylor, G., Nielsen, A., O'Brien, M., O'Gorman, T., Ono, Y., Oliver, H., Pamela, S., Pangione, L., Parra, F., Patel, A., Peebles, W., Peng, M., Perez, R., Pinches, S., Piron, L., Podesta, M., Price, M., Reinke, M., Ren, Y., Roach, C., Robinson, J., Romanelli, M., Rozhansky, V., Saarelma, S., Sangaroon, Siriyaporn, Saveliev, A., Scannell, R., Schekochihin, A., Sharapov, S., Sharples, R., Shevchenko, V., Silburn, S., Simpson, J., Storrs, J., Takase, Y., Tanabe, H., Tanaka, H., Taylor, D., Taylor, G., Thomas, D., Thomas-Davies, N., Thornton, A., Turnyanskiy, M., Valovic, M., Vann, R., Walkden, N., Wilson, H., Wyk, L. V., Yamada, T., and Zoletnik, S.

Abstract

The Mega Ampere Spherical Tokamak (MAST) programme is strongly focused on addressing key physics issues in preparation for operation of ITER as well as providing solutions for DEMO design choices. In this regard, MAST has provided key results in understanding and optimizing H-mode confinement, operating with smaller edge localized modes (ELMs), predicting and handling plasma exhaust and tailoring auxiliary current drive. In all cases, the high-resolution diagnostic capability on MAST is complemented by sophisticated numerical modelling to facilitate a deeper understanding. Mitigation of ELMs with resonant magnetic perturbations (RMPs) with toroidal mode number n(RMP) = 2, 3, 4, 6 has been demonstrated: at high and low collisionality; for the first ELM following the transition to high confinement operation; during the current ramp-up; and with rotating n(RMP) = 3 RMPs. n(RMP) = 4, 6 fields cause less rotation braking whilst the power to access H-mode is less with n(RMP) = 4 than n(RMP) = 3, 6. Refuelling with gas or pellets gives plasmas with mitigated ELMs and reduced peak heat flux at the same time as achieving good confinement. A synergy exists between pellet fuelling and RMPs, since mitigated ELMs remove fewer particles. Inter-ELM instabilities observed with Doppler backscattering are consistent with gyrokinetic simulations of micro-tearing modes in the pedestal. Meanwhile, ELM precursors have been strikingly observed with beam emission spectroscopy (BES) measurements. A scan in beta at the L-H transition shows that pedestal height scales strongly with core pressure. Gyro-Bohm normalized turbulent ion heat flux (as estimated from the BES data) is observed to decrease with increasing tilt of the turbulent eddies. Fast ion redistribution by energetic particle modes depends on density, and access to a quiescent domain with 'classical' fast ion transport is found above a critical density. Highly efficient electron Bernstein wave current drive (1 A W-1) has been achie

Published
2015
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16. Overview of MAST results

Author

Chapman, I.T., primary, Adamek, J., additional, Akers, R.J., additional, Allan, S., additional, Appel, L., additional, Asunta, O., additional, Barnes, M., additional, Ayed, N. Ben, additional, Bigelow, T., additional, Boeglin, W., additional, Bradley, J., additional, Brünner, J., additional, Cahyna, P., additional, Carr, M., additional, Caughman, J., additional, Cecconello, M., additional, Challis, C., additional, Chapman, S., additional, Chorley, J., additional, Colyer, G., additional, Conway, N., additional, Cooper, W.A., additional, Cox, M., additional, Crocker, N., additional, Crowley, B., additional, Cunningham, G., additional, Danilov, A., additional, Darrow, D., additional, Dendy, R., additional, Diallo, A., additional, Dickinson, D., additional, Diem, S., additional, Dorland, W., additional, Dudson, B., additional, Dunai, D., additional, Easy, L., additional, Elmore, S., additional, Field, A., additional, Fishpool, G., additional, Fox, M., additional, Fredrickson, E., additional, Freethy, S., additional, Garzotti, L., additional, Ghim, Y.C., additional, Gibson, K., additional, Graves, J., additional, Gurl, C., additional, Guttenfelder, W., additional, Ham, C., additional, Harrison, J., additional, Harting, D., additional, Havlickova, E., additional, Hawke, J., additional, Hawkes, N., additional, Hender, T., additional, Henderson, S., additional, Highcock, E., additional, Hillesheim, J., additional, Hnat, B., additional, Holgate, J., additional, Horacek, J., additional, Howard, J., additional, Huang, B., additional, Imada, K., additional, Jones, O., additional, Kaye, S., additional, Keeling, D., additional, Kirk, A., additional, Klimek, I., additional, Kocan, M., additional, Leggate, H., additional, Lilley, M., additional, Lipschultz, B., additional, Lisgo, S., additional, Liu, Y.Q., additional, Lloyd, B., additional, Lomanowski, B., additional, Lupelli, I., additional, Maddison, G., additional, Mailloux, J., additional, Martin, R., additional, McArdle, G., additional, McClements, K., additional, McMillan, B., additional, Meakins, A., additional, Meyer, H., additional, Michael, C., additional, Militello, F., additional, Milnes, J., additional, Morris, A.W., additional, Motojima, G., additional, Muir, D., additional, Nardon, E., additional, Naulin, V., additional, Naylor, G., additional, Nielsen, A., additional, O'Brien, M., additional, O'Gorman, T., additional, Ono, Y., additional, Oliver, H., additional, Pamela, S., additional, Pangione, L., additional, Parra, F., additional, Patel, A., additional, Peebles, W., additional, Peng, M., additional, Perez, R., additional, Pinches, S., additional, Piron, L., additional, Podesta, M., additional, Price, M., additional, Reinke, M., additional, Ren, Y., additional, Roach, C., additional, Robinson, J., additional, Romanelli, M., additional, Rozhansky, V., additional, Saarelma, S., additional, Sangaroon, S., additional, Saveliev, A., additional, Scannell, R., additional, Schekochihin, A., additional, Sharapov, S., additional, Sharples, R., additional, Shevchenko, V., additional, Silburn, S., additional, Simpson, J., additional, Storrs, J., additional, Takase, Y., additional, Tanabe, H., additional, Tanaka, H., additional, Taylor, D., additional, Taylor, G., additional, Thomas, D., additional, Thomas-Davies, N., additional, Thornton, A., additional, Turnyanskiy, M., additional, Valovic, M., additional, Vann, R., additional, Walkden, N., additional, Wilson, H., additional, Wyk, L.V., additional, Yamada, T., additional, and Zoletnik, S., additional

Published
2015
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17. Overview of physics results from MAST towards ITER/DEMO and the MAST Upgrade

Author

Meyer, H., Abel, I. G., Akers, R. J., Allan, A., Allan, S. Y., Appel, L. C., Asunta, O., Barnes, M., Barratt, N. C., Ben Ayed, N., Bradley, J. W., Canik, J., Cahyna, P., Cecconello, Marco, Challis, C. D., Chapman, I. T., Ciric, D., Colyer, G., Conway, N. J., Cox, M., Crowley, B. J., Cowley, S. C., Cunningham, G., Danilov, A., Darke, A., De Bock, M. F. M., De Temmerman, G., Dendy, R. O., Denner, P., Dickinson, D., Dnestrovsky, A. Y., Dnestrovsky, Y., Driscoll, M. D., Dudson, B., Dunai, D., Dunstan, M., Dura, P., Elmore, S., Field, A. R., Fishpool, G., Freethy, S., Fundamenski, W., Garzotti, L., Ghim, Y. C., Gibson, K. J., Gryaznevich, M. P., Harrison, J., Havlickova, E., Hawkes, N. C., Heidbrink, W. W., Hender, T. C., Highcock, E., Higgins, D., Hill, P., Hnat, B., Hole, M. J., Horacek, J., Howell, D. F., Imada, K., Jones, O., Kaveeva, E., Keeling, D., Kirk, A., Kocan, M., Lake, R. J., Lehnen, M., Leggate, H. J., Liang, Y., Lilley, M. K., Lisgo, S. W., Liu, Y. Q., Lloyd, B., Maddison, G. P., Mailloux, J., Martin, R., McArdle, G. J., McClements, K. G., McMillan, B., Michael, C., Militello, F., Molchanov, P., Mordijck, S., Morgan, T., Morris, A. W., Muir, D. G., Nardon, E., Naulin, V., Naylor, G., Nielsen, A. H., O'Brien, M. R., O'Gorman, T., Pamela, S., Parra, F. I., Patel, A., Pinches, S. D., Price, M. N., Roach, C. M., Robinson, J. R., Romanelli, M., Rozhansky, V., Saarelma, S., Sangaroon, S., Saveliev, A., Scannell, R., Seidl, J., Sharapov, S. E., Schekochihin, A. A., Shevchenko, V., Shibaev, S., Stork, D., Storrs, J., Sykes, A., Tallents, G. J., Tamain, P., Taylor, D., Temple, D., Thomas-Davies, N., Thornton, A., Turnyanskiy, M. R., Valovic, M., Vann, R. G. L., Verwichte, E., Voskoboynikov, P., Voss, G., Warder, S. E. V., Wilson, H. R., Wodniak, I., Zoletnik, S., Zagorski, R., Meyer, H., Abel, I. G., Akers, R. J., Allan, A., Allan, S. Y., Appel, L. C., Asunta, O., Barnes, M., Barratt, N. C., Ben Ayed, N., Bradley, J. W., Canik, J., Cahyna, P., Cecconello, Marco, Challis, C. D., Chapman, I. T., Ciric, D., Colyer, G., Conway, N. J., Cox, M., Crowley, B. J., Cowley, S. C., Cunningham, G., Danilov, A., Darke, A., De Bock, M. F. M., De Temmerman, G., Dendy, R. O., Denner, P., Dickinson, D., Dnestrovsky, A. Y., Dnestrovsky, Y., Driscoll, M. D., Dudson, B., Dunai, D., Dunstan, M., Dura, P., Elmore, S., Field, A. R., Fishpool, G., Freethy, S., Fundamenski, W., Garzotti, L., Ghim, Y. C., Gibson, K. J., Gryaznevich, M. P., Harrison, J., Havlickova, E., Hawkes, N. C., Heidbrink, W. W., Hender, T. C., Highcock, E., Higgins, D., Hill, P., Hnat, B., Hole, M. J., Horacek, J., Howell, D. F., Imada, K., Jones, O., Kaveeva, E., Keeling, D., Kirk, A., Kocan, M., Lake, R. J., Lehnen, M., Leggate, H. J., Liang, Y., Lilley, M. K., Lisgo, S. W., Liu, Y. Q., Lloyd, B., Maddison, G. P., Mailloux, J., Martin, R., McArdle, G. J., McClements, K. G., McMillan, B., Michael, C., Militello, F., Molchanov, P., Mordijck, S., Morgan, T., Morris, A. W., Muir, D. G., Nardon, E., Naulin, V., Naylor, G., Nielsen, A. H., O'Brien, M. R., O'Gorman, T., Pamela, S., Parra, F. I., Patel, A., Pinches, S. D., Price, M. N., Roach, C. M., Robinson, J. R., Romanelli, M., Rozhansky, V., Saarelma, S., Sangaroon, S., Saveliev, A., Scannell, R., Seidl, J., Sharapov, S. E., Schekochihin, A. A., Shevchenko, V., Shibaev, S., Stork, D., Storrs, J., Sykes, A., Tallents, G. J., Tamain, P., Taylor, D., Temple, D., Thomas-Davies, N., Thornton, A., Turnyanskiy, M. R., Valovic, M., Vann, R. G. L., Verwichte, E., Voskoboynikov, P., Voss, G., Warder, S. E. V., Wilson, H. R., Wodniak, I., Zoletnik, S., and Zagorski, R.

Abstract

New diagnostic, modelling and plant capability on the Mega Ampere Spherical Tokamak (MAST) have delivered important results in key areas for ITER/DEMO and the upcoming MAST Upgrade, a step towards future ST devices on the path to fusion currently under procurement. Micro-stability analysis of the pedestal highlights the potential roles of micro-tearing modes and kinetic ballooning modes for the pedestal formation. Mitigation of edge localized modes (ELM) using resonant magnetic perturbation has been demonstrated for toroidal mode numbers n = 3, 4, 6 with an ELM frequency increase by up to a factor of 9, compatible with pellet fuelling. The peak heat flux of mitigated and natural ELMs follows the same linear trend with ELM energy loss and the first ELM-resolved T-i measurements in the divertor region are shown. Measurements of flow shear and turbulence dynamics during L-H transitions show filaments erupting from the plasma edge whilst the full flow shear is still present. Off-axis neutral beam injection helps to strongly reduce the redistribution of fast-ions due to fishbone modes when compared to on-axis injection. Low-k ion-scale turbulence has been measured in L-mode and compared to global gyro-kinetic simulations. A statistical analysis of principal turbulence time scales shows them to be of comparable magnitude and reasonably correlated with turbulence decorrelation time. T-e inside the island of a neoclassical tearing mode allow the analysis of the island evolution without assuming specific models for the heat flux. Other results include the discrepancy of the current profile evolution during the current ramp-up with solutions of the poloidal field diffusion equation, studies of the anomalous Doppler resonance compressional Alfven eigenmodes, disruption mitigation studies and modelling of the new divertor design for MAST Upgrade. The novel 3D electron Bernstein synthetic imaging shows promising first data sensitive to the edge current profile and flows.

Published
2013
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19. Overview of physics results from MAST

Author

Lloyd, B., Akers, R. J., Alladio, F., Allan, S., Appel, L. C., Barnes, M., Barratt, N. C., Ben Ayed, N., Breizman, B. N., Cecconello, Marco, Challis, C. D., Chapman, I. T., Ciric, D., Colyer, G., Connor, J. W., Conway, N. J., Cox, M., Cowley, S. C., Cunningham, G., Darke, A., De Bock, M., Delchambre, E., De Temmerman, G., Dendy, R. O., Denner, P., Driscoll, M. D., Dudson, B., Dunai, D., Dunstan, M., Elmore, S., Field, A. R., Fishpool, G., Freethy, S., Garzotti, L., Gibson, K. J., Gryaznevich, M. P., Guttenfelder, W., Harrison, J., Hastie, R. J., Hawkes, N. C., Hender, T. C., Hnat, B., Howell, D. F., Hua, M. -D, Hubbard, A., Huysmans, G., Keeling, D., Kim, Y. C., Kirk, A., Liang, Y., Lilley, M. K., Lisak, M., Lisgo, S., Liu, Y. Q., Maddison, G. P., Maingi, R., Manhood, S. J., Martin, R., McArdle, G. J., McCone, J., Meyer, H., Michael, C., Mordijck, S., Morgan, T., Morris, A. W., Muir, D. G., Nardon, E., Naylor, G., O'Brien, M. R., O'Gorman, T., Palenik, J., Patel, A., Pinches, S. D., Price, M. N., Roach, C. M., Rozhansky, V., Saarelma, S., Sabbagh, S. A., Saveliev, A., Scannell, R., Sharapov, S. E., Shevchenko, V., Shibaev, S., Stork, D., Storrs, J., Suttrop, W., Sykes, A., Tamain, P., Taylor, D., Temple, D., Thomas-Davies, N., Thornton, A., Turnyanskiy, M. R., Valovic, M., Vann, R. G. L., Voss, G., Walsh, M. J., Warder, S. E. V., Wilson, H. R., Windridge, M., Wisse, M., Zoletnik, S., Lloyd, B., Akers, R. J., Alladio, F., Allan, S., Appel, L. C., Barnes, M., Barratt, N. C., Ben Ayed, N., Breizman, B. N., Cecconello, Marco, Challis, C. D., Chapman, I. T., Ciric, D., Colyer, G., Connor, J. W., Conway, N. J., Cox, M., Cowley, S. C., Cunningham, G., Darke, A., De Bock, M., Delchambre, E., De Temmerman, G., Dendy, R. O., Denner, P., Driscoll, M. D., Dudson, B., Dunai, D., Dunstan, M., Elmore, S., Field, A. R., Fishpool, G., Freethy, S., Garzotti, L., Gibson, K. J., Gryaznevich, M. P., Guttenfelder, W., Harrison, J., Hastie, R. J., Hawkes, N. C., Hender, T. C., Hnat, B., Howell, D. F., Hua, M. -D, Hubbard, A., Huysmans, G., Keeling, D., Kim, Y. C., Kirk, A., Liang, Y., Lilley, M. K., Lisak, M., Lisgo, S., Liu, Y. Q., Maddison, G. P., Maingi, R., Manhood, S. J., Martin, R., McArdle, G. J., McCone, J., Meyer, H., Michael, C., Mordijck, S., Morgan, T., Morris, A. W., Muir, D. G., Nardon, E., Naylor, G., O'Brien, M. R., O'Gorman, T., Palenik, J., Patel, A., Pinches, S. D., Price, M. N., Roach, C. M., Rozhansky, V., Saarelma, S., Sabbagh, S. A., Saveliev, A., Scannell, R., Sharapov, S. E., Shevchenko, V., Shibaev, S., Stork, D., Storrs, J., Suttrop, W., Sykes, A., Tamain, P., Taylor, D., Temple, D., Thomas-Davies, N., Thornton, A., Turnyanskiy, M. R., Valovic, M., Vann, R. G. L., Voss, G., Walsh, M. J., Warder, S. E. V., Wilson, H. R., Windridge, M., Wisse, M., and Zoletnik, S.

Abstract

Major developments on the Mega Amp Spherical Tokamak (MAST) have enabled important advances in support of ITER and the physics basis of a spherical tokamak (ST) based component test facility (CTF), as well as providing new insight into underlying tokamak physics. For example, L-H transition studies benefit from high spatial and temporal resolution measurements of pedestal profile evolution (temperature, density and radial electric field) and in support of pedestal stability studies the edge current density profile has been inferred from motional Stark effect measurements. The influence of the q-profile and E x B flow shear on transport has been studied in MAST and equilibrium flow shear has been included in gyro-kinetic codes, improving comparisons with the experimental data. H-modes exhibit a weaker q and stronger collisionality dependence of heat diffusivity than implied by IPB98(gamma, 2) scaling, which may have important implications for the design of an ST-based CTF. ELM mitigation, an important issue for ITER, has been demonstrated by applying resonant magnetic perturbations (RMPs) using both internal and external coils, but full stabilization of type-I ELMs has not been observed. Modelling shows the importance of including the plasma response to the RMP fields. MAST plasmas with q > 1 and weak central magnetic shear regularly exhibit a long-lived saturated ideal internal mode. Measured plasma braking in the presence of this mode compares well with neo-classical toroidal viscosity theory. In support of basic physics understanding, high resolution Thomson scattering measurements are providing new insight into sawtooth crash dynamics and neo-classical tearing mode critical island widths. Retarding field analyser measurements show elevated ion temperatures in the scrape-off layer of L-mode plasmas and, in the presence of type-I ELMs, ions with energy greater than 500 eV are detected 20 cm outside the separatrix. Disruption mitigation by massive gas injection h

Published
2011
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20. Overview of physics results from MAST

Author

Meyer, H., Akers, R. J., Alladio, F., Appel, L. C., Axon, K. B., Ben Ayed, N., Boerner, P., Buttery, R. J., Carolan, P. G., Ciric, D., Challis, C. D., Chapman, I. T., Coyler, G., Connor, J. W., Conway, N. J., Cowley, S., Cox, M., Counsell, G. F., Cunningham, G., Darke, A., deBock, M., deTemmerman, G., Dendy, R. O., Dowling, J., Dnestrovskij, A. Yu, Dnestrovskij, Yu. N., Dudson, B., Dunai, D., Dunstan, M., Field, A. R., Foster, A., Garzotti, L., Gibson, K., Gryaznevich, M. P., Guttenfelder, W., Hawkes, N. C., Harrison, J., Helander, P., Hender, T. C., Hnat, B., Hole, M. J., Howell, D. F., Hua, M. Duc, Hubbard, A., Istenic, M., Joiner, N., Keeling, D., Kirk, A., Koslowski, H. R., Liang, Y., Lilley, M., Lisgo, S., Lloyd, B., Maddison, G. P., Maingi, R., Mancuso, A., Manhood, S. J., Martin, R., McArdle, G. J., McCone, J., Michael, C., Micozzi, P., Morgan, T., Morris, A. W., Muir, D. G., Nardon, E., Naylor, G., O'Brien, M. R., O'Gorman, T., Patel, A., Pinches, S. D., Preinhaelter, J., Price, M. N., Rachlew, Elisabeth, Reiter, D., Roach, C. M., Rozhansky, V., Saarelma, S., Saveliev, A., Scannell, R., Sharapov, S. E., Shevchenko, V., Shibaev, S., Smith, H., Staebler, G. E., Stork, D., Storrs, J., Sykes, A., Tallents, S., Tamain, P., Taylor, D., Temple, D., Thomas-Davies, N., Thornton, A., Thyagaraja, A., Turnyanskiy, M. R., Urban, J., Valovic, M., Vann, R. G. L., Volpe, F., Voss, G., Walsh, M. J., Warder, S. E. V., Watkins, R., Wilson, H. R., Windridge, M., Wisse, M., Zabolotski, A., Zoletnik, S., Zolotukhin, O., Meyer, H., Akers, R. J., Alladio, F., Appel, L. C., Axon, K. B., Ben Ayed, N., Boerner, P., Buttery, R. J., Carolan, P. G., Ciric, D., Challis, C. D., Chapman, I. T., Coyler, G., Connor, J. W., Conway, N. J., Cowley, S., Cox, M., Counsell, G. F., Cunningham, G., Darke, A., deBock, M., deTemmerman, G., Dendy, R. O., Dowling, J., Dnestrovskij, A. Yu, Dnestrovskij, Yu. N., Dudson, B., Dunai, D., Dunstan, M., Field, A. R., Foster, A., Garzotti, L., Gibson, K., Gryaznevich, M. P., Guttenfelder, W., Hawkes, N. C., Harrison, J., Helander, P., Hender, T. C., Hnat, B., Hole, M. J., Howell, D. F., Hua, M. Duc, Hubbard, A., Istenic, M., Joiner, N., Keeling, D., Kirk, A., Koslowski, H. R., Liang, Y., Lilley, M., Lisgo, S., Lloyd, B., Maddison, G. P., Maingi, R., Mancuso, A., Manhood, S. J., Martin, R., McArdle, G. J., McCone, J., Michael, C., Micozzi, P., Morgan, T., Morris, A. W., Muir, D. G., Nardon, E., Naylor, G., O'Brien, M. R., O'Gorman, T., Patel, A., Pinches, S. D., Preinhaelter, J., Price, M. N., Rachlew, Elisabeth, Reiter, D., Roach, C. M., Rozhansky, V., Saarelma, S., Saveliev, A., Scannell, R., Sharapov, S. E., Shevchenko, V., Shibaev, S., Smith, H., Staebler, G. E., Stork, D., Storrs, J., Sykes, A., Tallents, S., Tamain, P., Taylor, D., Temple, D., Thomas-Davies, N., Thornton, A., Thyagaraja, A., Turnyanskiy, M. R., Urban, J., Valovic, M., Vann, R. G. L., Volpe, F., Voss, G., Walsh, M. J., Warder, S. E. V., Watkins, R., Wilson, H. R., Windridge, M., Wisse, M., Zabolotski, A., Zoletnik, S., and Zolotukhin, O.

Abstract

Several improvements to the MAST plant and diagnostics have facilitated new studies advancing the physics basis for ITER and DEMO, as well as for future spherical tokamaks (STs). Using the increased heating capabilities P-NBI <= 3.8 MW H-mode at I-P = 1.2 MA was accessed showing that the energy confinement on MAST scales more weakly with I-P and more strongly with B-t than in the ITER IPB98(y, 2) scaling. Measurements of the fuel retention of shallow pellets extrapolate to an ITER particle throughput of 70% of its original designed total throughput capacity. The anomalous momentum diffusion, chi(phi), is linked to the ion diffusion, chi(i), with a Prandtl number close to P-phi approximate to chi(phi)/chi(i) approximate to 1, although chi(i) approaches neoclassical values. New high spatial resolution measurements of the edge radial electric field, E-r, show that the position of steepest gradients in electron pressure and E-r (i.e. shearing rate) are coincident, but their magnitudes are not linked. The T-e pedestal width on MAST scales with root beta(ped)(pol) rather than rho(pol). The edge localized mode (ELM) frequency for type-IV ELMs, new in MAST, was almost doubled using n = 2 resonant magnetic perturbations from a set of four external coils (n = 1, 2). A new internal 12 coil set (n <= 3) has been commissioned. The filaments in the inter-ELM and L-mode phase are different from ELM filaments, and the characteristics in L-mode agree well with turbulence calculations. A variety of fast particle driven instabilities were studied from 10 kHz saturated fishbone like activity up to 3.8 MHz compressional Alfven eigenmodes. Fast particle instabilities also affect the off-axis NBI current drive, leading to fast ion diffusion of the order of 0.5 m(2) s(-1) and a reduction in the driven current fraction from 40% to 30%. EBW current drive start-up is demonstrated for the first time in a ST generating plasma currents up to 55 kA. Many of these studies contributed to the, QC 20110414

Published
2009
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22. Overview of physics results from MAST

Author

Lloyd, B., Akers, R. J., Alladio, F., Andrew, Y., Appel, L. C., Applegate, D., Axon, K. B., Ben Ayed, N., Bunting, C., Buttery, R. J., Carolan, P. G., Chapman, I., Ciric, D., Connor, J. W., Conway, N. J., Cox, M., Counsell, G. F., Cunningham, G., Darke, A., Delchambre, E., Dendy, R. O., Dowling, J., Dudson, B., Dunstan, M., Field, A. R., Foster, A., Gee, S., Garzotti, L., Gryaznevich, M. P., Gurchenko, A., Gusakov, E., Hawkes, N. C., Helander, P., Hender, T. C., Hnat, B., Howell, D. F., Joiner, N., Keeling, D., Kirk, A., Koch, B., Kuldkepp, Mattias, Lisgo, S., Lott, F., Maddison, G. P., Maingi, R., Mancuso, A., Manhood, S. J., Martin, R., McArdle, G. J., McCone, J., Meyer, H., Micozzi, P., Morris, A. W., Muir, D. G., Nelson, M., O'Brien, M. R., Patel, A., Pinches, S., Preinhaelter, J., Price, M. N., Rachlew, Elisabeth, Roach, C. M., Rozhansky, V., Saarelma, S., Saveliev, A., Scannell, R., Sharapov, S. E., Shevchenko, V., Shibaev, S., Stammers, K., Storrs, J., Surkov, A., Sykes, A., Tallents, S., Taylor, D., Thomas-Davies, N., Turnyanskiy, M. R., Urban, J., Valovic, M., Vann, R. G. L., Volpe, F., Voss, G., Walsh, M. J., Warder, S. E. V., Watkins, R., Wilson, H. R., Wisse, M., Lloyd, B., Akers, R. J., Alladio, F., Andrew, Y., Appel, L. C., Applegate, D., Axon, K. B., Ben Ayed, N., Bunting, C., Buttery, R. J., Carolan, P. G., Chapman, I., Ciric, D., Connor, J. W., Conway, N. J., Cox, M., Counsell, G. F., Cunningham, G., Darke, A., Delchambre, E., Dendy, R. O., Dowling, J., Dudson, B., Dunstan, M., Field, A. R., Foster, A., Gee, S., Garzotti, L., Gryaznevich, M. P., Gurchenko, A., Gusakov, E., Hawkes, N. C., Helander, P., Hender, T. C., Hnat, B., Howell, D. F., Joiner, N., Keeling, D., Kirk, A., Koch, B., Kuldkepp, Mattias, Lisgo, S., Lott, F., Maddison, G. P., Maingi, R., Mancuso, A., Manhood, S. J., Martin, R., McArdle, G. J., McCone, J., Meyer, H., Micozzi, P., Morris, A. W., Muir, D. G., Nelson, M., O'Brien, M. R., Patel, A., Pinches, S., Preinhaelter, J., Price, M. N., Rachlew, Elisabeth, Roach, C. M., Rozhansky, V., Saarelma, S., Saveliev, A., Scannell, R., Sharapov, S. E., Shevchenko, V., Shibaev, S., Stammers, K., Storrs, J., Surkov, A., Sykes, A., Tallents, S., Taylor, D., Thomas-Davies, N., Turnyanskiy, M. R., Urban, J., Valovic, M., Vann, R. G. L., Volpe, F., Voss, G., Walsh, M. J., Warder, S. E. V., Watkins, R., Wilson, H. R., and Wisse, M.

Abstract

Substantial advances have been made on the Mega AmpÚre Spherical Tokamak (MAST). The parameter range of the MAST confinement database has been extended and it now also includes pellet-fuelled discharges. Good pellet retention has been observed in H-mode discharges without triggering an ELM or an H/L transition during peripheral ablation of low speed pellets. Co-ordinated studies on MAST and DIII-D demonstrate a strong link between the aspect ratio and the beta scaling of H-mode energy confinement, consistent with that obtained when MAST data were merged with a subset of the ITPA database. Electron and ion ITBs are readily formed and their evolution has been investigated. Electron and ion thermal diffusivities have been reduced to values close to the ion neoclassical level. Error field correction coils have been used to determine the locked mode threshold scaling which is comparable to that in conventional aspect ratio tokamaks. The impact of plasma rotation on sawteeth has been investigated and the results have been well-modelled using the MISHKA-F code. Alfvén cascades have been observed in discharges with reversed magnetic shear. Measurements during off-axis NBCD and heating are consistent with classical fast ion modelling and indicate efficient heating and significant driven current. Central electron Bernstein wave heating has been observed via the O-X-B mode conversion process in special magnetically compressed plasmas. Plasmas with low pedestal collisionality have been established and further insight has been gained into the characteristics of filamentary structures at the plasma edge. Complex behaviour of the divertor power loading during plasma disruptions has been revealed by high resolution infra-red measurements., QC 20110414 ISI anger titeln som "Overview MAST" Har ingått i: 21st IAEA Fusion Energy Conference, Chengdu, PEOPLES R CHINA, OCT 16-21, 2006

Published
2007
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23. Overview of physics results from MAST

Author

Meyer, H., primary, Akers, R.J., additional, Alladio, F., additional, Appel, L.C., additional, Axon, K.B., additional, Ayed, N. Ben, additional, Boerner, P., additional, Buttery, R.J., additional, Carolan, P.G., additional, Ciric, D., additional, Challis, C.D., additional, Chapman, I.T., additional, Coyler, G., additional, Connor, J.W., additional, Conway, N.J., additional, Cowley, S., additional, Cox, M., additional, Counsell, G.F., additional, Cunningham, G., additional, Darke, A., additional, deBock, M., additional, deTemmerman, G., additional, Dendy, R.O., additional, Dowling, J., additional, Dnestrovskij, A. Yu, additional, Dnestrovskij, Yu.N., additional, Dudson, B., additional, Dunai, D., additional, Dunstan, M., additional, Field, A.R., additional, Foster, A., additional, Garzotti, L., additional, Gibson, K., additional, Gryaznevich, M.P., additional, Guttenfelder, W., additional, Hawkes, N.C., additional, Harrison, J., additional, Helander, P., additional, Hender, T.C., additional, Hnat, B., additional, Hole, M.J., additional, Howell, D.F., additional, Hua, M. Duc, additional, Hubbard, A., additional, Istenic, M., additional, Joiner, N., additional, Keeling, D., additional, Kirk, A., additional, Koslowski, H.R., additional, Liang, Y., additional, Lilley, M., additional, Lisgo, S., additional, Lloyd, B., additional, Maddison, G.P., additional, Maingi, R., additional, Mancuso, A., additional, Manhood, S.J., additional, Martin, R., additional, McArdle, G.J., additional, McCone, J., additional, Michael, C., additional, Micozzi, P., additional, Morgan, T., additional, Morris, A.W., additional, Muir, D.G., additional, Nardon, E., additional, Naylor, G., additional, O'Brien, M.R., additional, O'Gorman, T., additional, Patel, A., additional, Pinches, S.D., additional, Preinhaelter, J., additional, Price, M.N., additional, Rachlew, E., additional, Reiter, D., additional, Roach, C.M., additional, Rozhansky, V., additional, Saarelma, S., additional, Saveliev, A., additional, Scannell, R., additional, Sharapov, S.E., additional, Shevchenko, V., additional, Shibaev, S., additional, Smith, H., additional, Staebler, G.E., additional, Stork, D., additional, Storrs, J., additional, Sykes, A., additional, Tallents, S., additional, Tamain, P., additional, Taylor, D., additional, Temple, D., additional, Thomas-Davies, N., additional, Thornton, A., additional, Thyagaraja, A., additional, Turnyanskiy, M.R., additional, Urban, J., additional, Valovic, M., additional, Vann, R.G.L., additional, Volpe, F., additional, Voss, G, additional, Walsh, M.J., additional, Warder, S.E.V., additional, Watkins, R., additional, Wilson, H.R., additional, Windridge, M., additional, Wisse, M., additional, Zabolotski, A., additional, Zoletnik, S., additional, and Zolotukhin, O., additional

Published
2009
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25. Overview of physics results from MAST

Author

Lloyd, B., primary, Akers, R.J., additional, Alladio, F., additional, Andrew, Y., additional, Appel, L.C., additional, Applegate, D., additional, Axon, K.B., additional, Ben Ayed, N., additional, Bunting, C., additional, Buttery, R.J., additional, Carolan, P.G., additional, Chapman, I., additional, Ciric, D., additional, Connor, J.W., additional, Conway, N.J., additional, Cox, M., additional, Counsell, G.F., additional, Cunningham, G., additional, Darke, A., additional, Delchambre, E., additional, Dendy, R.O., additional, Dowling, J., additional, Dudson, B., additional, Dunstan, M., additional, Field, A.R., additional, Foster, A., additional, Gee, S., additional, Garzotti, L., additional, Gryaznevich, M.P., additional, Gurchenko, A., additional, Gusakov, E., additional, Hawkes, N.C., additional, Helander, P., additional, Hender, T.C., additional, Hnat, B., additional, Howell, D.F., additional, Joiner, N., additional, Keeling, D., additional, Kirk, A., additional, Koch, B., additional, Kuldkepp, M., additional, Lisgo, S., additional, Lott, F., additional, Maddison, G.P., additional, Maingi, R., additional, Mancuso, A., additional, Manhood, S.J., additional, Martin, R., additional, McArdle, G.J., additional, McCone, J., additional, Meyer, H., additional, Micozzi, P., additional, Morris, A.W., additional, Muir, D.G., additional, Nelson, M., additional, O'Brien, M.R., additional, Patel, A., additional, Pinches, S., additional, Preinhaelter, J., additional, Price, M.N., additional, Rachlew, E., additional, Roach, C.M., additional, Rozhansky, V., additional, Saarelma, S., additional, Saveliev, A., additional, Scannell, R., additional, Sharapov, S.E., additional, Shevchenko, V., additional, Shibaev, S., additional, Stammers, K., additional, Storrs, J., additional, Surkov, A., additional, Sykes, A., additional, Tallents, S., additional, Taylor, D., additional, Thomas-Davies, N., additional, Turnyanskiy, M.R., additional, Urban, J., additional, Valovic, M., additional, Vann, R.G.L., additional, Volpe, F., additional, Voss, G., additional, Walsh, M.J., additional, Warder, S.E.V., additional, Watkins, R., additional, Wilson, H.R., additional, and Wisse, M., additional

Published
2007
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26. Overview of MAST results

Author

Counsell, G.F, primary, Akers, R.J, additional, Appel, L.C, additional, Applegate, D, additional, Axon, K.B, additional, Baranov, Y, additional, Brickley, C, additional, Bunting, C, additional, Buttery, R.J, additional, Carolan, P.G, additional, Challis, C, additional, Ciric, D, additional, Conway, N.J, additional, Cox, M, additional, Cunningham, G, additional, Darke, A, additional, Dnestrovskij, A, additional, Dowling, J, additional, Dudson, B, additional, Dunstan, M.R, additional, Delchambre, E, additional, Field, A.R, additional, Foster, A, additional, Gee, S, additional, Gryaznevich, M.P, additional, Helander, P, additional, Hender, T.C, additional, Hole, M, additional, Howell, D.H, additional, Joiner, N, additional, Keeling, D, additional, Kirk, A, additional, Lehane, I.P, additional, Lisgo, S, additional, Lloyd, B, additional, Lott, F, additional, Maddison, G.P, additional, Manhood, S.J, additional, Martin, R, additional, McArdle, G.J, additional, McClements, K.G, additional, Meyer, H, additional, Morris, A.W, additional, Nelson, M, additional, O'Brien, M.R, additional, Patel, A, additional, Pinfold, T, additional, Preinhaelter, J, additional, Price, M.N, additional, Roach, C.M, additional, Rozhansky, V, additional, Saarelma, S, additional, Saveliev, A, additional, Scannell, R, additional, Sharapov, S, additional, Shevchenko, V, additional, Shibaev, S, additional, Stammers, K, additional, Storrs, J, additional, Sykes, A, additional, Tabasso, A, additional, Tallents, S, additional, Taylor, D, additional, Tournianski, M.R, additional, Turner, A, additional, Turri, G, additional, Valovic, M, additional, Volpe, F, additional, Voss, G, additional, Walsh, M.J, additional, Watkins, J.R, additional, Wilson, H.R, additional, Wisse, M, additional, and Teams, the MAST, NBI and ECRH, additional

Published
2005
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27. MAST and the impact of low aspect ratio on tokamak physics

Author

Lloyd, B, primary, Ahn, J-W, additional, Akers, R J, additional, Appel, L C, additional, Applegate, D, additional, Axon, K B, additional, Baranov, Y, additional, Brickley, C, additional, Bunting, C, additional, Buttery, R J, additional, Carolan, P G, additional, Challis, C, additional, Ciric, D, additional, Conway, N J, additional, Cox, M, additional, Counsell, G F, additional, Cunningham, G, additional, Darke, A, additional, Dnestrovskij, A, additional, Dowling, J, additional, Dudson, B, additional, Dunstan, M R, additional, Field, A R, additional, Gee, S, additional, Gryaznevich, M P, additional, Helander, P, additional, Hender, T C, additional, Hole, M, additional, Joiner, N, additional, Keeling, D, additional, Kirk, A, additional, Lehane, I P, additional, Lott, F, additional, Maddison, G P, additional, Manhood, S J, additional, Martin, R, additional, McArdle, G J, additional, McClements, K G, additional, Meyer, H, additional, Morris, A W, additional, Nelson, M, additional, O'Brien, M R, additional, Patel, A, additional, Pinfold, T, additional, Preinhaelter, J, additional, Price, M N, additional, Roach, C M, additional, Rozhansky, V, additional, Saarelma, S, additional, Saveliev, A, additional, Scannell, R, additional, Sharapov, S, additional, Shevchenko, V, additional, Shibaev, S, additional, Stammers, K, additional, Storrs, J, additional, Sykes, A, additional, Tabasso, A, additional, Taylor, D, additional, Tournianski, M R, additional, Turner, A, additional, Turri, G, additional, Valovic, M, additional, Volpe, F, additional, Voss, G, additional, Walsh, M J, additional, Watkins, J R, additional, Wilson, H R, additional, Wisse, M, additional, and Teams, the MAST, NBI and ECRH, additional

Published
2004
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28. Transport and confinement in the Mega Ampère Spherical Tokamak (MAST) plasma

Author

Akers, R J, primary, Ahn, J W, additional, Antar, G Y, additional, Appel, L C, additional, Applegate, D, additional, Brickley, C, additional, Bunting, C, additional, Carolan, P G, additional, Challis, C D, additional, Conway, N J, additional, Counsell, G F, additional, Dendy, R O, additional, Dudson, B, additional, Field, A R, additional, Kirk, A, additional, Lloyd, B, additional, Meyer, H F, additional, Morris, A W, additional, Patel, A, additional, Roach, C M, additional, Rohzansky, V, additional, Sykes, A, additional, Taylor, D, additional, Tournianski, M R, additional, Valovic, M, additional, Wilson, H R, additional, Axon, K B, additional, Buttery, R J, additional, Ciric, D, additional, Cunningham, G, additional, Dowling, J, additional, Dunstan, M R, additional, Gee, S J, additional, Gryaznevich, M P, additional, Helander, P, additional, Keeling, D L, additional, Knight, P J, additional, Lott, F, additional, Loughlin, M J, additional, Manhood, S J, additional, Martin, R, additional, McArdle, G J, additional, Price, M N, additional, Stammers, K, additional, Storrs, J, additional, Walsh, M J, additional, and Team, the MAST and NBI, additional

Published
2003
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29. Commissioning of the wideband matching system for ICRH of ELMy JET plasmas.

Author

Lamalle, P. U., Goulding, R., Monakhov, I., Sibley, A. G. H., Simon, M., Storrs, J., and Walden, A.

Subjects
BROADBAND communication systems, PLASMA generators, RADIO frequency
Abstract

The conventional JET ICRH antenna matching system cannot respond to large and rapid load variations induced by the ELMs. Unacceptably large bursts of reflected power occur at the generators, severely limiting the ability to deliver RF power to ELMy plasmas. A wideband matching system based on prematching sliding impedances and fast frequency control is under commissioning on one of the antenna arrays. When suitably configured, the new system, which operates in 4 frequency bands inside the JET plant range, should strongly reduce the ELMinduced power reflection by rapid adjustments of generator frequency. The paper reports recent progress achieved in its commissioning. Successful operation of the fast frequency control loop has been demonstrated during ELMs, and work is underway to bring the system to full operation. [ABSTRACT FROM AUTHOR]

Published
2001

32. Overview of MAST results

Author

Chapman, I. T., Adamek, J., Akers, R. J., Allan, S., Appel, L., Asunta, O., Barnes, M., Ben Ayed, N., Bigelow, T., Boeglin, W., Bradley, J., Bruenner, J., Cahyna, P., Carr, M., Caughman, J., Cecconello, M., Challis, C., Chapman, S., Chorley, J., Colyer, G., Conway, N., Cooper, W. A., Cox, M., Crocker, N., Crowley, B., Cunningham, G., Danilov, A., Darrow, D., Dendy, R., Diallo, A., Dickinson, D., Diem, S., Dorland, W., Dudson, B., Dunai, D., Easy, L., Elmore, S., Field, A., Fishpool, G., Fox, M., Fredrickson, E., Freethy, S., Garzotti, L., Ghim, Y. C., Gibson, K., Graves, J., Gurl, C., Guttenfelder, W., Ham, C., Harrison, J., Harting, D., Havlickova, E., Hawke, J., Hawkes, N., Hender, T., Henderson, S., Highcock, E., Hillesheim, J., Hnat, B., Holgate, J., Horacek, J., Howard, J., Huang, B., Imada, K., Jones, O., Kaye, S., Keeling, D., Kirk, A., Klimek, I., Kocan, M., Leggate, H., Lilley, M., Lipschultz, B., Lisgo, S., Liu, Y. Q., Lloyd, B., Lomanowski, B., Lupelli, I., Maddison, G., Mailloux, J., Martin, R., Mcardle, G., Mcclements, K., Mcmillan, B., Meakins, A., Meyer, H., Michael, C., Militello, F., Milnes, J., Morris, A. W., Motojima, G., Muir, D., Nardon, E., Naulin, V., Naylor, G., Nielsen, A., O'Brien, M., O'Gorman, T., Ono, Y., Oliver, H., Pamela, S., Pangione, L., Parra, F., Patel, A., Peebles, W., Peng, M., Perez, R., Pinches, S., Piron, L., Podesta, M., Price, M., Reinke, M., Ren, Y., Roach, C., Robinson, J., Romanelli, M., Rozhansky, V., Saarelma, S., Sangaroon, S., Saveliev, A., Scannell, R., Schekochihin, A., Sharapov, S., Sharples, R., Shevchenko, V., Silburn, S., Simpson, J., Storrs, J., Takase, Y., Tanabe, H., Tanaka, H., Taylor, D., Taylor, G., Thomas, D., Thomas-Davies, N., Thornton, A., Turnyanskiy, M., Valovic, M., Vann, R., Walkden, N., Wilson, H., Wyk, L. V., Yamada, T., Zoletnik, S., MAST Team, and MAST Upgrade Team

Subjects
high confinement operation, Physics::Plasma Physics, MAST, numerical modelling, RMPs
Abstract

The Mega Ampere Spherical Tokamak (MAST) programme is strongly focused on addressing key physics issues in preparation for operation of ITER as well as providing solutions for DEMO design choices. In this regard, MAST has provided key results in understanding and optimizing H-mode confinement, operating with smaller edge localized modes (ELMs), predicting and handling plasma exhaust and tailoring auxiliary current drive. In all cases, the high-resolution diagnostic capability on MAST is complemented by sophisticated numerical modelling to facilitate a deeper understanding. Mitigation of ELMs with resonant magnetic perturbations (RMPs) with toroidal mode number n(RMP) = 2, 3, 4, 6 has been demonstrated: at high and low collisionality; for the first ELM following the transition to high confinement operation; during the current ramp-up; and with rotating n(RMP) = 3 RMPs. n(RMP) = 4, 6 fields cause less rotation braking whilst the power to access H-mode is less with n(RMP) = 4 than n(RMP) = 3, 6. Refuelling with gas or pellets gives plasmas with mitigated ELMs and reduced peak heat flux at the same time as achieving good confinement. A synergy exists between pellet fuelling and RMPs, since mitigated ELMs remove fewer particles. Inter-ELM instabilities observed with Doppler backscattering are consistent with gyrokinetic simulations of micro-tearing modes in the pedestal. Meanwhile, ELM precursors have been strikingly observed with beam emission spectroscopy (BES) measurements. A scan in beta at the L-H transition shows that pedestal height scales strongly with core pressure. Gyro-Bohm normalized turbulent ion heat flux (as estimated from the BES data) is observed to decrease with increasing tilt of the turbulent eddies. Fast ion redistribution by energetic particle modes depends on density, and access to a quiescent domain with 'classical' fast ion transport is found above a critical density. Highly efficient electron Bernstein wave current drive (1 A W-1) has been achieved in solenoid-free start-up. A new proton detector has characterized escaping fusion products. Langmuir probes and a high-speed camera suggest filaments play a role in particle transport in the private flux region whilst coherence imaging has measured scrape-off layer (SOL) flows. BOUT++ simulations show that fluxes due to filaments are strongly dependent on resistivity and magnetic geometry of the SOL, with higher radial fluxes at higher resistivity. Finally, MAST Upgrade is due to begin operation in 2016 to support ITER preparation and importantly to operate with a Super-X divertor to test extended leg concepts for particle and power exhaust.

33. Factory buildings, Naugatuck Valley.

Author

Storrs, J. W. and Storrs, J. W.

Subjects
Factories., Usines., factories (structures), Factories., Naugatuck River Valley (Conn.), Naugatuck, Vallée du (Conn.), Connecticut Naugatuck River Valley.
Abstract

A factory building with a cupola is reflected in a river or mill pond. The buildings of a large town in a river valley between steep hills are in the background. The roofs of two buildings, possibly houses or multiple-family dwellings, are in the foreground. Leafless trees, woodpiles, and laundry on clotheslines are along the water's edge.

34. Button factory, Naugatuck Valley.

Author

Storrs, J. W. and Storrs, J. W.

Subjects
Button industry., Factories., Mills and mill-work., Boutons Industrie., Usines., factories (structures), Mills and mill-work, Button industry, Factories, Naugatuck River Valley (Conn.), Naugatuck, Vallée du (Conn.), Connecticut Naugatuck River Valley
Abstract

A small factory complex is located beside a river. The largest building has a cupola and flagpole. Leafless trees and houses are on a hill in the background. Laundry hangs from a clothesline in the left foreground.

36. GONE POSTAL.

Author

M., Victoria, M., Tyler, Storrs, J., M., James, and R., Chris

Subjects
MOTORCYCLES, PERIODICALS, HELMETS
Abstract

The article presents questions and answers related to the 2012 Husqvarna 250 motocross bike, the skills needed to work for the magazine, and the handle grips and Bell Moto 9 helmet that the magazine are giving away.

Published
2013

37. GONE POSTAL.

Author

M., James, Storrs, J., T., Ben, H., Brett, and S., Jake

Subjects
LETTERS to the editor, MOTORCYCLES, MOTORCYCLE racing, HELMETS, MOTORSPORTS
Abstract

Several letters to the editor are presented that discuss various topics such as one wherein the sender expresses his gratitude to his parents for supporting his passion with motorcycles, another on the Unadilla 2012 race, and another one on educating riders about helmets.

Published
2012

39. THE PREVENTION OF POSTOPERATIVE VOMITING AFTER ABORTION: METOCLOPRAMIDE

Author

CLARK, MARGARET M. and STORRS, J. A.

Abstract

The anti-emetic properties of metoclopramide were investigated by means of a double-blind trial in patients after evacuation of the uterus following incomplete abortion. Vomiting occurred in only 6 of 50 patients who were given metoclopramide 20 mg by intramuscular injection immediately after operation, compared with 24 in a group of 50 in whom normal saline was injected. This difference is significant. There was a reduction in other postoperative side effects although all the differences were not statistically significant.

Published
1969
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41. Investigation of a chronic single-stage sheep Fontan model.

Author

Kelly JM, Hu Z, Takaesu F, Watanabe T, Storrs J, Blais B, Yuhara S, Morrison A, Nelson K, Ulziibayar A, Heuer E, Anderson C, Jimenez M, Leland J, Malbrue R, Arsuaga-Zorrilla C, Goodchild L, Naguib A, McKee C, Varner J, DeShetler C, Spiess J, Harrison A, Boe B, Armstrong AK, Salavitabar A, Hor K, Krishnamurthy R, Yates AR, Shinoka T, Carrillo SA, Davis ME, Marsden AL, and Breuer CK

Abstract

Objectives: Our goal was to conduct a hemodynamic analysis of a novel animal model of Fontan physiology. Poor late-term outcomes in Fontan patients are believed to arise from Fontan-induced hemodynamics, but the mechanisms remain poorly understood. Recent advances in surgical experimentation have resulted in the development of a chronic sheep model of Fontan physiology; however, detailed analysis of this model is lacking., Methods: We created a single-stage Fontan model in juvenile sheep with normal biventricular circulation. The superior vena cava was anastomosed to the main pulmonary artery, and the inferior vena cava was connected to the main pulmonary artery using an expanded polytetrafluoroethylene conduit. Longitudinal hemodynamics, including catheterization and magnetic resonance imaging were evaluated., Results: Four out of 12 animals survived, with the longest surviving animal living 3 years after single-stage Fontan. We showed a significant era effect regarding survival (1 out of 8 and subsequently 3 out of 4 animals surviving beyond 2 months) attributed in large part to the procedural learning curve. Key characteristics of Fontan hemodynamics, namely systemic venous hypertension and low normal cardiac output, were observed. However, recapitulation of passive human Fontan hemodynamics is affected by volume loading of the right ventricle given an anatomic difference in sheep azygous venous anatomy draining to the coronary sinus., Conclusions: A significant learning curve exists to ensure long-term survival and future surgical modifications, including banding of the main pulmonary artery and ligation of the azygous to coronary sinus connection are promising strategies to improve the fidelity of model hemodynamics., Competing Interests: The authors reported no conflicts of interest. The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest., (© 2024 The Authors.)

Published
2024
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42. Harmonized Multisite MRI-Based Quantification of Human Liver Fat and Stiffness: A Pilot Study.

Author

Carmichael OT, Singh M, Bashir A, Russell AM, Bolding M, Redden DT, Storrs J, Willoughby WR, Howard-Claudio C, Hsia DS, Kimberly RP, Gray ME, Ravussin E, and Denney TS

Subjects
Adult, Humans, Pilot Projects, Reproducibility of Results, Liver pathology, Magnetic Resonance Imaging methods, Obesity pathology, Non-alcoholic Fatty Liver Disease pathology
Abstract

Background: Nonalcoholic fatty liver disease (NAFLD) is a leading cause of end-stage liver disease. NAFLD diagnosis and follow-up relies on a combination of clinical data, liver imaging, and/or liver biopsy. However, intersite imaging differences impede diagnostic consistency and reduce the repeatability of the multisite clinical trials necessary to develop effective treatments., Purpose/hypothesis: The goal of this pilot study was to harmonize commercially available 3 T magnetic resonance imaging (MRI) measurements of liver fat and stiffness in human participants across academic sites and MRI vendors., Study Type: Cohort., Subjects: Four community-dwelling adults with obesity., Field Strength/sequence: 1.5 and 3 T, multiecho 3D imaging, PRESS, and GRE., Assessment: Harmonized proton density fat fraction (PDFF) and magnetic resonance spectroscopy (MRS) protocols were used to quantify the FF of synthetic phantoms and human participants with obesity using standard acquisition parameters at four sites that had four different 3 T MRI instruments. In addition, a harmonized magnetic resonance elastography (MRE) protocol was used to quantify liver stiffness among participants at two different sites at 1.5 and 3 T field strengths. Data were sent to a single data coordinating site for postprocessing., Statistical Tests: Linear regression in MATLAB, ICC analyses using SAS 9.4, one-sided 95% confidence intervals for the ICC., Results: PDFF and MRS FF measurements were highly repeatable among sites in both humans and phantoms. MRE measurements of liver stiffness in three individuals at two sites using one 1.5 T and one 3 T instrument showed repeatability that was high although lower than that of MRS and PDFF., Conclusions: We demonstrated harmonization of PDFF, MRS, and MRE-based quantification of liver fat and stiffness through synthetic phantoms, traveling participants, and standardization of postprocessing analysis. Multisite MRI harmonization could contribute to multisite clinical trials assessing the efficacy of interventions and therapy for NAFLD., Level of Evidence: 2 TECHNICAL EFFICACY STAGE: 2., (© 2023 International Society for Magnetic Resonance in Medicine.)

Published
2024
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43. Comparative Effectiveness of Tumor Response Assessment Methods: Standard of Care Versus Computer-Assisted Response Evaluation.

Author

Allen BC, Florez E, Sirous R, Lirette ST, Griswold M, Remer EM, Wang ZJ, Bieszczad JE, Cox KL, Goenka AH, Howard-Claudio CM, Kang HC, Nandwana SB, Sanyal R, Shinagare AB, Henegan JC, Storrs J, Davenport MS, Ganeshan B, Vasanji A, Rini B, and Smith AD

Subjects
Aged, Clinical Trials, Phase III as Topic, Female, Humans, Image Processing, Computer-Assisted, Male, Medical Informatics methods, Middle Aged, Multicenter Studies as Topic, Neoplasms diagnosis, Neoplasms therapy, Observer Variation, Standard of Care, Surveys and Questionnaires, Tomography, X-Ray Computed methods, Medical Oncology methods, Quality Assurance, Health Care methods, Treatment Outcome
Abstract

Purpose: To compare the effectiveness of metastatic tumor response evaluation with computed tomography using computer-assisted versus manual methods., Materials and Methods: In this institutional review board-approved, Health Insurance Portability and Accountability Act-compliant retrospective study, 11 readers from 10 different institutions independently categorized tumor response according to three different therapeutic response criteria by using paired baseline and initial post-therapy computed tomography studies from 20 randomly selected patients with metastatic renal cell carcinoma who were treated with sunitinib as part of a completed phase III multi-institutional study. Images were evaluated with a manual tumor response evaluation method (standard of care) and with computer-assisted response evaluation (CARE) that included stepwise guidance, interactive error identification and correction methods, automated tumor metric extraction, calculations, response categorization, and data and image archiving. A crossover design, patient randomization, and 2-week washout period were used to reduce recall bias. Comparative effectiveness metrics included error rate and mean patient evaluation time., Results: The standard-of-care method, on average, was associated with one or more errors in 30.5% (6.1 of 20) of patients, whereas CARE had a 0.0% (0.0 of 20) error rate ( P < .001). The most common errors were related to data transfer and arithmetic calculation. In patients with errors, the median number of error types was 1 (range, 1 to 3). Mean patient evaluation time with CARE was twice as fast as the standard-of-care method (6.4 minutes v 13.1 minutes; P < .001)., Conclusion: CARE reduced errors and time of evaluation, which indicated better overall effectiveness than manual tumor response evaluation methods that are the current standard of care.

Published
2017
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44. Jaw ache--an occupational hazard?

Author

Storrs J

Subjects
Female, Habits, Humans, Male, Occupational Diseases etiology, Occupational Diseases physiopathology, Posture, Risk Reduction Behavior, Temporomandibular Joint Dysfunction Syndrome etiology, Temporomandibular Joint Dysfunction Syndrome physiopathology, Mastication physiology, Occupational Diseases diagnosis, Temporomandibular Joint Dysfunction Syndrome diagnosis
Published
2015
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45. Detecting brain structural changes as biomarker from magnetic resonance images using a local feature based SVM approach.

Author

Chen Y, Storrs J, Tan L, Mazlack LJ, Lee JH, and Lu LJ

Subjects
Alzheimer Disease pathology, Artifacts, Bipolar Disorder pathology, Female, Humans, Magnetic Resonance Imaging, Male, Parkinson Disease pathology, Algorithms, Brain pathology, Image Interpretation, Computer-Assisted methods, Support Vector Machine
Abstract

Detecting brain structural changes from magnetic resonance (MR) images can facilitate early diagnosis and treatment of neurological and psychiatric diseases. Many existing methods require an accurate deformation registration, which is difficult to achieve and therefore prevents them from obtaining high accuracy. We develop a novel local feature based support vector machine (SVM) approach to detect brain structural changes as potential biomarkers. This approach does not require deformation registration and thus is less influenced by artifacts such as image distortion. We represent the anatomical structures based on scale invariant feature transform (SIFT). Likelihood scores calculated using feature-based morphometry is used as the criterion to categorize image features into three classes (healthy, patient and noise). Regional SVMs are trained to classify the three types of image features in different brain regions. Only healthy and patient features are used to predict the disease status of new brain images. An ensemble classifier is built from the regional SVMs to obtain better prediction accuracy. We apply this approach to 3D MR images of Alzheimer's disease, Parkinson's disease and bipolar disorder. The classification accuracy ranges between 70% and 87%. The highly predictive disease-related regions, which represent significant anatomical differences between the healthy and diseased, are shown in heat maps. The common and disease-specific brain regions are identified by comparing the highly predictive regions in each disease. All of the top-ranked regions are supported by literature. Thus, this approach will be a promising tool for assisting automatic diagnosis and advancing mechanism studies of neurological and psychiatric diseases., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Published
2014
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46. Full diffusion characterization implicates regionally disparate neuropathology in mild cognitive impairment.

Author

Boespflug EL, Storrs J, Sadat-Hossieny S, Eliassen J, Shidler M, Norris M, and Krikorian R

Subjects
Aged, Anisotropy, Brain Mapping, Female, Functional Laterality physiology, Humans, Male, Neuropsychological Tests, Psychiatric Status Rating Scales, Alzheimer Disease pathology, Brain pathology, Cognitive Dysfunction pathology, Diffusion Tensor Imaging, Nerve Fibers, Myelinated pathology
Abstract

Diffusion tensor imaging (DTI) is used to detect tissue pathology. In Alzheimer's disease (AD) research, DTI has been used to elucidate differences in disease stages and to track progression over time and clinical severity. Many of these studies have identified the fornix as particularly vulnerable in the early stages of pathology associated with memory decline in prodromal AD. Emerging research suggests principal tensor components, axial (DA) and radial (DR) diffusivity, are more sensitive to underlying tissue pathology than are mean diffusivity (MD) and fractional anisotropy (FA). Given the established regionally specific tissue decline in MCI, we examined components of the full diffusion tensor (MD, FA, DR, and DA) for sensitivity to regional pathology associated with specific memory deficits in 18 individuals with MCI. We investigated multiple regions of interest, including fornix, temporal stem, and control regions for association with severity of impairment on multiple memory measures, including a type of neuropsychological task shown to be particularly sensitive to early memory decline in MCI. Better paired associate learning was selectively associated with lower DA (β = -0.663, p = 0.003), but not with DR, MD, or FA of the temporal stems. Conversely, better paired associate learning was associated with lower DR (β = -0.523, p = 0.026), higher FA (β = 0.498, p = 0.036), and lower MD (β = -0.513, p = 0.030), but not DA in the fornix. No association was found for control regions, or for control cognitive measures. These findings suggest disparate pathology of temporal stems and fornix white matter in association with early memory impairment in MCI. Further, they highlight the methodological importance of evaluating the full tensor, rather than only summative metrics in research using DTI.

Published
2014
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47. Solubility and chemistry of materials encountered by beryllium mine and ore extraction workers: relation to risk.

Author

Deubner DC, Sabey P, Huang W, Fernandez D, Rudd A, Johnson WP, Storrs J, and Larson R

Subjects
Air Pollutants, Occupational adverse effects, Air Pollutants, Occupational immunology, Aluminum Silicates adverse effects, Aluminum Silicates chemistry, Aluminum Silicates immunology, Beryllium adverse effects, Beryllium immunology, Cell Proliferation, Cells, Cultured, Humans, Lymphocytes drug effects, Risk Factors, Air Pollutants, Occupational chemistry, Berylliosis etiology, Beryllium chemistry, Hypersensitivity etiology, Mining, Occupational Diseases etiology, Occupational Exposure adverse effects, Solubility
Abstract

Objective: Beryllium mine and ore extraction mill workers have low rates of beryllium sensitization and chronic beryllium disease relative to the level of beryllium exposure. The objective was to relate these rates to the solubility and composition of the mine and mill materials., Method: Medical surveillance and exposure data were summarized. Dissolution of BeO, ore materials and beryllium hydroxide, Be(OH)(2) was measured in synthetic lung fluid., Result: The ore materials were more soluble than BeO at pH 7.2 and similar at pH 4.5. Be(OH)(2) was more soluble than BeO at both pH. Aluminum dissolved along with beryllium from ore materials., Conclusion: Higher solubility of beryllium ore materials and Be(OH)(2) at pH 7.2 might shorten particle longevity in the lung. The aluminum content of the ore materials might inhibit the cellular immune response to beryllium.

Published
2011
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48. Dissolution and nanoparticle generation behavior of Be-associated materials in synthetic lung fluid using inductively coupled plasma mass spectroscopy and flow field-flow fractionation.

Author

Huang W, Fernandez D, Rudd A, Johnson WP, Deubner D, Sabey P, Storrs J, and Larsen R

Subjects
Aluminum Silicates chemistry, Berylliosis metabolism, Body Fluids chemistry, Body Fluids metabolism, Humans, Hydrogen-Ion Concentration, Lung metabolism, Microscopy, Electron, Scanning, Particle Size, Silicon Dioxide chemistry, Solubility, Beryllium chemistry, Fractionation, Field Flow methods, Mass Spectrometry methods, Metal Nanoparticles chemistry, Models, Biological
Abstract

Various Be-containing micro-particle suspensions were equilibrated with simulated lung fluid (SLF) to examine their dissolution behavior as well as the potential generation of nanoparticles. The motivation for this study was to explore the relationship between dissolution/particle generation behaviors of Be-containing materials relevant to Be-ore processing, and their epidemiologically indicated inhalation toxicities. Limited data suggest that BeO is associated with higher rates of beryllium sensitization (BS) and chronic beryllium disease (CBD) relative to the other five relevant materials studied: bertrandite-containing ore, beryl-containing ore, frit (a processing intermediate), Be(OH)₂ (a processing intermediate), and silica (control). These materials were equilibrated with SLF at two pH values (4.5 and 7.2) to reflect inter- and intra-cellular environments in lung tissue. Concentrations of Be, Al, and Si in SLF increased linearly during the first 20 days of equilibration, and then rose slowly, or in some cases reached a maximum, and subsequently decreased. Relative to the other materials, BeO produced relatively low Be concentration in solution at pH 7.2; and relatively high Be concentration in solution at pH 4.5 during the first 20 days of equilibration. For both pH values, however, the Be concentration in SLF normalized to Be content of the material was lowest for BeO, demonstrating that BeO was distinct among the four other Be-containing materials in terms of its persistence as a source of Be to the SLF solution. Following 149 days of equilibration, the SLF solutions were fractionated using flow-field flow fractionation (FlFFF) with detection via ICP-MS. For all materials, nanoparticles (which were formed during equilibration) were dominantly distributed in the 10-100 nm size range. Notably, BeO produced the least nanoparticle-associated Be mass (other than silica) at both pH values. Furthermore, BeO produced the highest Be concentrations in the size range corresponding to < 3 kDa (determined via centrifugal ultrafiltration), indicating that in addition to persistence, the BeO produced the highest concentrations of truly dissolved (potentially ionic) Be relative to the other materials. Mass balance analysis showed reasonable sample recoveries during FFF fractionation (50-100%), whereas recoveries during ICP-MS (relative to acidified standards) were much lower (5-10%), likely due to inefficiencies in nebulizing and ionizing the nanoparticles., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Published
2011
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49. Creating a continuum of care for chronically underserved children.

Author

McKee J, Storrs J, and Humphrey S

Subjects
Adolescent, Child, Community Health Services, Hospitals, Private, Humans, Medically Underserved Area, North Carolina, Organizational Innovation, Awards and Prizes, Continuity of Patient Care, Foster Home Care methods, Hospitals, Psychiatric, Mental Health Services
Abstract

Background: Grandfather Home for Children, a nonprofit residential treatment center in North Carolina, serves children with histories of abuse who exhibit sexual behavior problems and acute physical aggression. In June 2000, it launched an initiative to create placement resources for children who had been identified as chronically underserved-foster care, adoption services, and other appropriate community services., Methods: A total of 638 children served by Grandfather Home for Children were included in this study. The data were collected during a six-year period (October 1999-September 2005). The data to assess the agency's goals was collected through the agency's general performance indicators that are gathered on a quarterly and yearly basis, based on the agency's fiscal year. Performance improvement activities included substantive changes in administrative, staffing, training, and information systems., Results: Between 1999 and 2005 the agency's initiative achieved a 342% increase in the number of children it was able to serve, a 33% decrease in the average length of stay for children in care and a 721% increase in the percentage of children served in their home community, and 100% of the foster children had two or fewer placements., Discussion: The initiative to create a continuum of care has enabled the agency to successfully provide step-down opportunities and serve more children in the least restrictive environment for a shorter period of time with fewer placement changes than observed in comparative statistics at both the federal or state level.

Published
2007
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50. CT brain prescriptions in Talairach space: a new clinical standard.

Author

Weiss KL, Storrs J, Weiss JL, and Strub W

Subjects
Adolescent, Adult, Aged, Aged, 80 and over, Female, Humans, Magnetic Resonance Imaging standards, Male, Middle Aged, Palate diagnostic imaging, Reference Standards, Reproducibility of Results, Brain diagnostic imaging, Tomography, X-Ray Computed standards
Abstract

Background and Purpose: Head CT prescriptions are currently plagued by intra- and intersubject image variance and do not match standardized MR imaging planes. We developed and tested a simple method to improve CT precision and approximate the Talairach reference standard advocated for MR imaging., Methods: We retrospectively reviewed midline sagittal T2-weighted brain MR images of 126 consecutive patients to determine the mean angle subtended by the Talairach anterior commissure-posterior commissure (AC-PC) line and the hard palate. On the basis of this data set, a new head CT protocol was instituted with pitch similarly prescribed relative to the hard palate as identified on the lateral CT scout film. We then compared the precision of the new protocol, our former method (nominally parallel to the orbito-meatal line) and fixed-gantry angulation. Two head CT studies from 50 consecutive patients imaged with our old protocol and 50 consecutive patients imaged with our new protocol were reviewed for a total of 200 CT examinations., Results: The Talairach AC-PC line was rotated 12.0 degrees +/- 6.1 degrees from the hard palate line and 15.6 degrees +/- 10.1 degrees from the axial plane of the magnet. The new CT protocol approximated the Talairach-referenced MR images obtained at our institution and improved intrapatient CT scan precision compared with fixed-gantry selection (P <.004) and compared with our previous prescription technique (P <.064; P <.025, controlling for excessive head extension)., Conclusion: By prescribing CT images angled +12 degrees from the hard palate, a structure readily identified by technologists, interscan precision can be improved and Talairach-referenced MR imaging studies can be approximated. Along with AC-PC-referenced MR imaging studies, we advocate this CT protocol as a new clinical standard.

Published
2004

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