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1. Cortical abnormalities in bipolar disorder: an MRI analysis of 6503 individuals from the ENIGMA Bipolar Disorder Working Group.

Author

Hibar, DP, Westlye, LT, Doan, NT, Jahanshad, N, Cheung, JW, Ching, CRK, Versace, A, Bilderbeck, AC, Uhlmann, A, Mwangi, B, Krämer, B, Overs, B, Hartberg, CB, Abé, C, Dima, D, Grotegerd, D, Sprooten, E, Bøen, E, Jimenez, E, Howells, FM, Delvecchio, G, Temmingh, H, Starke, J, Almeida, JRC, Goikolea, JM, Houenou, J, Beard, LM, Rauer, L, Abramovic, L, Bonnin, M, Ponteduro, MF, Keil, M, Rive, MM, Yao, N, Yalin, N, Najt, P, Rosa, PG, Redlich, R, Trost, S, Hagenaars, S, Fears, SC, Alonso-Lana, S, van Erp, TGM, Nickson, T, Chaim-Avancini, TM, Meier, TB, Elvsåshagen, T, Haukvik, UK, Lee, WH, Schene, AH, Lloyd, AJ, Young, AH, Nugent, A, Dale, AM, Pfennig, A, McIntosh, AM, Lafer, B, Baune, BT, Ekman, CJ, Zarate, CA, Bearden, CE, Henry, C, Simhandl, C, McDonald, C, Bourne, C, Stein, DJ, Wolf, DH, Cannon, DM, Glahn, DC, Veltman, DJ, Pomarol-Clotet, E, Vieta, E, Canales-Rodriguez, EJ, Nery, FG, Duran, FLS, Busatto, GF, Roberts, G, Pearlson, GD, Goodwin, GM, Kugel, H, Whalley, HC, Ruhe, HG, Soares, JC, Fullerton, JM, Rybakowski, JK, Savitz, J, Chaim, KT, Fatjó-Vilas, M, Soeiro-de-Souza, MG, Boks, MP, Zanetti, MV, Otaduy, MCG, Schaufelberger, MS, Alda, M, Ingvar, M, Phillips, ML, Kempton, MJ, Bauer, M, Landén, M, and Lawrence, NS

Subjects
Brain, Cerebral Cortex, Frontal Lobe, Prefrontal Cortex, Temporal Lobe, Humans, Magnetic Resonance Imaging, Case-Control Studies, Bipolar Disorder, Psychotic Disorders, Age Factors, Sex Factors, Adolescent, Adult, Middle Aged, Female, Male, Young Adult, Neuroimaging, Gray Matter, Clinical Research, Serious Mental Illness, Biomedical Imaging, Brain Disorders, Mental Health, Neurosciences, 2.1 Biological and endogenous factors, Aetiology, Mental health, Neurological, Biological Sciences, Medical and Health Sciences, Psychology and Cognitive Sciences, Psychiatry
Abstract

Despite decades of research, the pathophysiology of bipolar disorder (BD) is still not well understood. Structural brain differences have been associated with BD, but results from neuroimaging studies have been inconsistent. To address this, we performed the largest study to date of cortical gray matter thickness and surface area measures from brain magnetic resonance imaging scans of 6503 individuals including 1837 unrelated adults with BD and 2582 unrelated healthy controls for group differences while also examining the effects of commonly prescribed medications, age of illness onset, history of psychosis, mood state, age and sex differences on cortical regions. In BD, cortical gray matter was thinner in frontal, temporal and parietal regions of both brain hemispheres. BD had the strongest effects on left pars opercularis (Cohen's d=-0.293; P=1.71 × 10-21), left fusiform gyrus (d=-0.288; P=8.25 × 10-21) and left rostral middle frontal cortex (d=-0.276; P=2.99 × 10-19). Longer duration of illness (after accounting for age at the time of scanning) was associated with reduced cortical thickness in frontal, medial parietal and occipital regions. We found that several commonly prescribed medications, including lithium, antiepileptic and antipsychotic treatment showed significant associations with cortical thickness and surface area, even after accounting for patients who received multiple medications. We found evidence of reduced cortical surface area associated with a history of psychosis but no associations with mood state at the time of scanning. Our analysis revealed previously undetected associations and provides an extensive analysis of potential confounding variables in neuroimaging studies of BD.

Published
2018

2. Cortical abnormalities in adults and adolescents with major depression based on brain scans from 20 cohorts worldwide in the ENIGMA Major Depressive Disorder Working Group

Author

Schmaal, L, Hibar, DP, Sämann, PG, Hall, GB, Baune, BT, Jahanshad, N, Cheung, JW, van Erp, TGM, Bos, D, Ikram, MA, Vernooij, MW, Niessen, WJ, Tiemeier, H, Hofman, A, Wittfeld, K, Grabe, HJ, Janowitz, D, Bülow, R, Selonke, M, Völzke, H, Grotegerd, D, Dannlowski, U, Arolt, V, Opel, N, Heindel, W, Kugel, H, Hoehn, D, Czisch, M, Couvy-Duchesne, B, Rentería, ME, Strike, LT, Wright, MJ, Mills, NT, de Zubicaray, GI, McMahon, KL, Medland, SE, Martin, NG, Gillespie, NA, Goya-Maldonado, R, Gruber, O, Krämer, B, Hatton, SN, Lagopoulos, J, Hickie, IB, Frodl, T, Carballedo, A, Frey, EM, van Velzen, LS, Penninx, BWJH, van Tol, M-J, van der Wee, NJ, Davey, CG, Harrison, BJ, Mwangi, B, Cao, B, Soares, JC, Veer, IM, Walter, H, Schoepf, D, Zurowski, B, Konrad, C, Schramm, E, Normann, C, Schnell, K, Sacchet, MD, Gotlib, IH, MacQueen, GM, Godlewska, BR, Nickson, T, McIntosh, AM, Papmeyer, M, Whalley, HC, Hall, J, Sussmann, JE, Li, M, Walter, M, Aftanas, L, Brack, I, Bokhan, NA, Thompson, PM, and Veltman, DJ

Subjects
Biological Psychology, Biomedical and Clinical Sciences, Clinical Sciences, Psychology, Major Depressive Disorder, Serious Mental Illness, Neurosciences, Biomedical Imaging, Depression, Basic Behavioral and Social Science, Mental Health, Brain Disorders, Clinical Research, Pediatric, Behavioral and Social Science, 2.3 Psychological, social and economic factors, Aetiology, 2.1 Biological and endogenous factors, Neurological, Mental health, Adolescent, Adult, Brain, Cerebral Cortex, Depressive Disorder, Major, Female, Frontal Lobe, Gray Matter, Gyrus Cinguli, Humans, Magnetic Resonance Imaging, Male, Neuroimaging, Prefrontal Cortex, Temporal Lobe, Biological Sciences, Medical and Health Sciences, Psychology and Cognitive Sciences, Psychiatry, Clinical sciences, Biological psychology, Clinical and health psychology
Abstract

The neuro-anatomical substrates of major depressive disorder (MDD) are still not well understood, despite many neuroimaging studies over the past few decades. Here we present the largest ever worldwide study by the ENIGMA (Enhancing Neuro Imaging Genetics through Meta-Analysis) Major Depressive Disorder Working Group on cortical structural alterations in MDD. Structural T1-weighted brain magnetic resonance imaging (MRI) scans from 2148 MDD patients and 7957 healthy controls were analysed with harmonized protocols at 20 sites around the world. To detect consistent effects of MDD and its modulators on cortical thickness and surface area estimates derived from MRI, statistical effects from sites were meta-analysed separately for adults and adolescents. Adults with MDD had thinner cortical gray matter than controls in the orbitofrontal cortex (OFC), anterior and posterior cingulate, insula and temporal lobes (Cohen's d effect sizes: -0.10 to -0.14). These effects were most pronounced in first episode and adult-onset patients (>21 years). Compared to matched controls, adolescents with MDD had lower total surface area (but no differences in cortical thickness) and regional reductions in frontal regions (medial OFC and superior frontal gyrus) and primary and higher-order visual, somatosensory and motor areas (d: -0.26 to -0.57). The strongest effects were found in recurrent adolescent patients. This highly powered global effort to identify consistent brain abnormalities showed widespread cortical alterations in MDD patients as compared to controls and suggests that MDD may impact brain structure in a highly dynamic way, with different patterns of alterations at different stages of life.

Published
2017

3. High flux expansion divertor studies in NSTX

Author

Soukhanovskii, V. A., Maingi, R., Bell, R. E., Gates, D. A., Kaita, R., Kugel, H. W., LeBlanc, B. P., Maqueda, R., Menard, J. E., Mueller, D., Paul, S. F., Raman, R., and Roquemore, A. L.

Subjects
Physics - Plasma Physics
Abstract

High flux expansion divertor studies have been carried out in the National Spherical Torus Experiment using steady-state X-point height variations from 22 to 5-6 cm. Small-ELM H-mode confinement was maintained at all X-point heights. Divertor flux expansions from 6 to 26-28 were obtained, with associated reduction in X-point connection length from 5-6 m to 2 m. Peak divertor heat flux was reduced from 7-8 MW/m$^2$ to 1-2 MW/m$^2$. In low X-point configuration, outer strike point became nearly detached. Among factors affecting deposition of parallel heat flux in the divertor, the flux expansion factor appeared to be dominant

Published
2009

4. Overview of physics results from the conclusive operation of the National Spherical Torus Experiment

Author

Sabbagh, SA, Ahn, J-W, Allain, J, Andre, R, Balbaky, A, Bastasz, R, Battaglia, D, Bell, M, Bell, R, Beiersdorfer, P, Belova, E, Berkery, J, Betti, R, Bialek, J, Bigelow, T, Bitter, M, Boedo, J, Bonoli, P, Boozer, A, Bortolon, A, Boyle, D, Brennan, D, Breslau, J, Buttery, R, Canik, J, Caravelli, G, Chang, C, Crocker, N, Darrow, D, Davis, B, Delgado-Aparicio, L, Diallo, A, Ding, S, D'Ippolito, D, Domier, C, Dorland, W, Ethier, S, Evans, T, Ferron, J, Finkenthal, M, Foley, J, Fonck, R, Frazin, R, Fredrickson, E, Fu, G, Gates, D, Gerhardt, S, Glasser, A, Gorelenkov, N, Gray, T, Guo, Y, Guttenfelder, W, Hahm, T, Harvey, R, Hassanein, A, Heidbrink, W, Hill, K, Hirooka, Y, Hooper, EB, Hosea, J, Humphreys, D, Indireshkumar, K, Jaeger, F, Jarboe, T, Jardin, S, Jaworski, M, Kaita, R, Kallman, J, Katsuro-Hopkins, O, Kaye, S, Kessel, C, Kim, J, Kolemen, E, Kramer, G, Krasheninnikov, S, Kubota, S, Kugel, H, La Haye, RJ, Lao, L, LeBlanc, B, Lee, W, Lee, K, Leuer, J, Levinton, F, Liang, Y, Liu, D, Lore, J, Luhmann, N, Maingi, R, Majeski, R, Manickam, J, Mansfield, D, Maqueda, R, Mazzucato, E, McLean, A, McCune, D, McGeehan, B, McKee, G, Medley, S, and Meier, E

Subjects
Atomic, Molecular, Nuclear, Particle and Plasma Physics, Fluids & Plasmas
Abstract

Research on the National Spherical Torus Experiment, NSTX, targets physics understanding needed for extrapolation to a steady-state ST Fusion Nuclear Science Facility, pilot plant, or DEMO. The unique ST operational space is leveraged to test physics theories for next-step tokamak operation, including ITER. Present research also examines implications for the coming device upgrade, NSTX-U. An energy confinement time, τE, scaling unified for varied wall conditions exhibits a strong improvement of BTτE with decreased electron collisionality, accentuated by lithium (Li) wall conditioning. This result is consistent with nonlinear microtearing simulations that match the experimental electron diffusivity quantitatively and predict reduced electron heat transport at lower collisionality. Beam-emission spectroscopy measurements in the steep gradient region of the pedestal indicate the poloidal correlation length of turbulence of about ten ion gyroradii increases at higher electron density gradient and lower Ti gradient, consistent with turbulence caused by trapped electron instabilities. Density fluctuations in the pedestal top region indicate ion-scale microturbulence compatible with ion temperature gradient and/or kinetic ballooning mode instabilities. Plasma characteristics change nearly continuously with increasing Li evaporation and edge localized modes (ELMs) stabilize due to edge density gradient alteration. Global mode stability studies show stabilizing resonant kinetic effects are enhanced at lower collisionality, but in stark contrast have almost no dependence on collisionality when the plasma is off-resonance. Combined resistive wall mode radial and poloidal field sensor feedback was used to control n = 1 perturbations and improve stability. The disruption probability due to unstable resistive wall modes (RWMs) was surprisingly reduced at very high βN/li > 10 consistent with low frequency magnetohydrodynamic spectroscopy measurements of mode stability. Greater instability seen at intermediate βN is consistent with decreased kinetic RWM stabilization. A model-based RWM state-space controller produced long-pulse discharges exceeding βN = 6.4 and βN/li = 13. Precursor analysis shows 96.3% of disruptions can be predicted with 10 ms warning and a false positive rate of only 2.8%. Disruption halo currents rotate toroidally and can have significant toroidal asymmetry. Global kinks cause measured fast ion redistribution, with full-orbit calculations showing redistribution from the core outward and towards V∥/V = 1 where destabilizing compressional Alfvén eigenmode resonances are expected. Applied 3D fields altered global Alfvén eigenmode characteristics. High-harmonic fast-wave (HHFW) power couples to field lines across the entire width of the scrape-off layer, showing the importance of the inclusion of this phenomenon in designing future RF systems. The snowflake divertor configuration enhanced by radiative detachment showed large reductions in both steady-state and ELM heat fluxes (ELMing peak values down from 19 MW m-2 to less than 1.5 MW m-2). Toroidal asymmetry of heat deposition was observed during ELMs or by 3D fields. The heating power required for accessing H-mode decreased by 30% as the triangularity was decreased by moving the X-point to larger radius, consistent with calculations of the dependence of E × B shear in the edge region on ion heat flux and X-point radius. Co-axial helicity injection reduced the inductive start-up flux, with plasmas ramped to 1 MA requiring 35% less inductive flux. Non-inductive current fraction (NICF) up to 65% is reached experimentally with neutral beam injection at plasma current Ip = 0.7 MA and between 70-100% with HHFW application at Ip = 0.3 MA. NSTX-U scenario development calculations project 100% NICF for a large range of 0.6 < Ip (MA) < 1.35. © 2013 IAEA, Vienna.

Published
2013

5. Overview of physics results from NSTX

Author

Raman, R, Ahn, J-W, Allain, JP, Andre, R, Bastasz, R, Battaglia, D, Beiersdorfer, P, Bell, M, Bell, R, Belova, E, Berkery, J, Betti, R, Bialek, J, Bigelow, T, Bitter, M, Boedo, J, Bonoli, P, Boozer, A, Bortolon, A, Brennan, D, Breslau, J, Buttery, R, Canik, J, Caravelli, G, Chang, C, Crocker, NA, Darrow, D, Davis, W, Delgado-Aparicio, L, Diallo, A, Ding, S, D'Ippolito, D, Domier, C, Dorland, W, Ethier, S, Evans, T, Ferron, J, Finkenthal, M, Foley, J, Fonck, R, Frazin, R, Fredrickson, E, Fu, G, Gates, D, Gerhardt, S, Glasser, A, Gorelenkov, N, Gray, T, Guo, Y, Guttenfelder, W, Hahm, T, Harvey, R, Hassanein, A, Heidbrink, W, Hill, K, Hirooka, Y, Hooper, EB, Hosea, J, Hu, B, Humphreys, D, Indireshkumar, K, Jaeger, F, Jarboe, T, Jardin, S, Jaworski, M, Kaita, R, Kallman, J, Katsuro-Hopkins, O, Kaye, S, Kessel, C, Kim, J, Kolemen, E, Krasheninnikov, S, Kubota, S, Kugel, H, La Haye, R, Lao, L, LeBlanc, B, Lee, W, Lee, K, Leuer, J, Levinton, F, Liang, Y, Liu, D, Luhmann, N, Maingi, R, Majeski, R, Manickam, J, Mansfield, D, Maqueda, R, Mazzucato, E, McLean, A, McCune, D, McGeehan, B, McKee, G, Medley, S, Menard, J, Menon, M, Meyer, H, and Mikkelsen, D

Subjects
Atomic, Molecular, Nuclear, Particle and Plasma Physics, Fluids & Plasmas
Abstract

In the last two experimental campaigns, the low aspect ratio NSTX has explored physics issues critical to both toroidal confinement physics and ITER. Experiments have made extensive use of lithium coatings for wall conditioning, correction of non-axisymmetric field errors and control of n = 1 resistive wall modes (RWMs) to produce high-performance neutral-beam heated discharges extending to 1.7 s in duration with non-inductive current fractions up to 0.7. The RWM control coils have been used to trigger repetitive ELMs with high reliability, and they have also contributed to an improved understanding of both neoclassical tearing mode and RWM stabilization physics, including the interplay between rotation and kinetic effects on stability. High harmonic fast wave (HHFW) heating has produced plasmas with central electron temperatures exceeding 6 keV. The HHFW heating was used to show that there was a 20-40% higher power threshold for the L-H transition for helium than for deuterium plasmas. A new diagnostic showed a depletion of the fast-ion density profile over a broad spatial region as a result of toroidicity-induced Alfvén eigenmodes (TAEs) and energetic-particle modes (EPMs) bursts. In addition, it was observed that other modes (e.g. global Alfvén eigenmodes) can trigger TAE and EPM bursts, suggesting that fast ions are redistributed by high-frequency AEs. The momentum pinch velocity determined by a perturbative technique decreased as the collisionality was reduced, although the pinch to diffusion ratio, Vpinch/χ, remained approximately constant. The mechanisms of deuterium retention by graphite and lithium-coated graphite plasma-facing components have been investigated. To reduce divertor heat flux, a novel divertor configuration, the 'snowflake' divertor, was tested in NSTX and many beneficial aspects were found. A reduction in the required central solenoid flux has been realized in NSTX when discharges initiated by coaxial helicity injection were ramped in current using induction. The resulting plasmas have characteristics needed to meet the objectives of the non-inductive start-up and ramp-up program of NSTX. © 2011 IAEA, Vienna.

Published
2011

6. Overview of results from the National Spherical Torus Experiment (NSTX)

Author

Gates, DA, Ahn, J, Allain, J, Andre, R, Bastasz, R, Bell, M, Bell, R, Belova, E, Berkery, J, Betti, R, Bialek, J, Biewer, T, Bigelow, T, Bitter, M, Boedo, J, Bonoli, P, Boozer, A, Brennan, D, Breslau, J, Brower, D, Bush, C, Canik, J, Caravelli, G, Carter, M, Caughman, J, Chang, C, Choe, W, Crocker, N, Darrow, D, Delgado-Aparicio, L, Diem, S, D'Ippolito, D, Domier, C, Dorland, W, Efthimion, P, Ejiri, A, Ershov, N, Evans, T, Feibush, E, Fenstermacher, M, Ferron, J, Finkenthal, M, Foley, J, Frazin, R, Fredrickson, E, Fu, G, Funaba, H, Gerhardt, S, Glasser, A, Gorelenkov, N, Grisham, L, Hahm, T, Harvey, R, Hassanein, A, Heidbrink, W, Hill, K, Hillesheim, J, Hillis, D, Hirooka, Y, Hosea, J, Hu, B, Humphreys, D, Idehara, T, Indireshkumar, K, Ishida, A, Jaeger, F, Jarboe, T, Jardin, S, Jaworski, M, Ji, H, Jung, H, Kaita, R, Kallman, J, Katsuro-Hopkins, O, Kawahata, K, Kawamori, E, Kaye, S, Kessel, C, Kim, J, Kimura, H, Kolemen, E, Krasheninnikov, S, Krstic, P, Ku, S, Kubota, S, Kugel, H, La Haye, R, Lao, L, LeBlanc, B, Lee, W, Lee, K, Leuer, J, Levinton, F, Liang, Y, Liu, D, Luhmann, N, Maingi, R, Majeski, R, Manickam, J, and Mansfield, D

Subjects
Atomic, Molecular, Nuclear, Particle and Plasma Physics, Fluids & Plasmas
Abstract

The mission of the National Spherical Torus Experiment (NSTX) is the demonstration of the physics basis required to extrapolate to the next steps for the spherical torus (ST), such as a plasma facing component test facility (NHTX) or an ST based component test facility (ST-CTF), and to support ITER. Key issues for the ST are transport, and steady state high β operation. To better understand electron transport, a new high-k scattering diagnostic was used extensively to investigate electron gyro-scale fluctuations with varying electron temperature gradient scale length. Results from n = 3 braking studies are consistent with the flow shear dependence of ion transport. New results from electron Bernstein wave emission measurements from plasmas with lithium wall coating applied indicate transmission efficiencies near 70% in H-mode as a result of reduced collisionality. Improved coupling of high harmonic fast-waves has been achieved by reducing the edge density relative to the critical density for surface wave coupling. In order to achieve high bootstrap current fraction, future ST designs envision running at very high elongation. Plasmas have been maintained on NSTX at very low internal inductance li ∼ 0.4 with strong shaping (κ ∼ 2.7, δ ∼ 0.8) with βN approaching the with-wall β-limit for several energy confinement times. By operating at lower collisionality in this regime, NSTX has achieved record non-inductive current drive fraction fNI ∼ 71%. Instabilities driven by super-Alfvénic ions will be an important issue for all burning plasmas, including ITER. Fast ions from NBI on NSTX are super-Alfvénic. Linear toroidal Alfvén eigenmode thresholds and appreciable fast ion loss during multi-mode bursts are measured and these results are compared with theory. The impact of n > 1 error fields on stability is an important result for ITER. Resistive wall mode/resonant field amplification feedback combined with n = 3 error field control was used on NSTX to maintain plasma rotation with β above the no-wall limit. Other highlights are results of lithium coating experiments, momentum confinement studies, scrape-off layer width scaling, demonstration of divertor heat load mitigation in strongly shaped plasmas and coupling of coaxial helicity injection plasmas to ohmic heating ramp-up. These results advance the ST towards next step fusion energy devices such as NHTX and ST-CTF. © 2009 IAEA, Vienna.

Published
2009

7. TFTR DT experiments

Author

Strachan, JD, Batha, S, Beer, M, Bell, MG, Bell, RE, Belov, A, Berk, H, Bernabei, S, Bitter, M, Breizman, B, Bretz, NL, Budny, R, Bush, CE, Callen, J, Cauffman, S, Chang, CS, Chang, Z, Cheng, CZ, Darrow, DS, Dendy, RO, Dorland, W, Duong, H, Efthimion, PC, Ernst, D, Evenson, H, Fisch, NJ, Fisher, R, Fonck, RJ, Fredrickson, ED, Fu, GY, Furth, HP, Gorelenkov, NN, Goloborod'ko, V Ya, Grek, B, Grisham, LR, Hammett, GW, Hawryluk, RJ, Heidbrink, W, Herrmann, HW, Herrmann, MC, Hill, KW, Hogan, J, Hooper, B, Hosea, JC, Houlberg, WA, Hughes, M, Jassby, DL, Jobes, FC, Johnson, DW, Kaita, R, Kaye, S, Kesner, J, Kim, JS, Kissick, M, Krasilnikov, AV, Kugel, H, Kumar, A, Lam, NT, Lamarche, P, Leblanc, B, Levinton, FM, Ludescher, C, Machuzak, J, Majeski, RP, Manickam, J, Mansfield, DK, Mauel, M, Mazzucato, E, McChesney, J, McCune, DC, McKee, G, McGuire, KM, Meade, DM, Medley, SS, Mikkelsen, DR, Mirnov, SV, Mueller, D, Nagayama, Y, Navratil, GA, Nazikian, R, Okabayashi, M, Osakabe, M, Owens, DK, Park, HK, Park, W, Paul, SF, Petrov, MP, Phillips, CK, Phillips, M, Phillips, P, Ramsey, AT, Rice, B, Redi, MH, Rewoldt, G, Reznik, S, Roquemore, AL, Rogers, J, Ruskov, E, Sabbagh, SA, and Sasao, M

Subjects
Atomic, Molecular, Nuclear, Particle and Plasma Physics, Other Physical Sciences, Fluids & Plasmas
Abstract

The Tokamak Fusion Test Reactor (TFTR) is a large tokamak which has performed experiments with 50:50 deuterium-tritium fuelled plasmas. Since 1993, TFTR has produced about 1090 D-T plasmas using about 100 grams of tritium and producing about 1.6 GJ of D-T fusion energy. These plasmas have significant populations of 3.5 MeV alphas (the charged D-T fusion product). TFTR research has focused on alpha particle confinement, alpha driven modes, and alpha heating studies. Maximum D-T fusion power production has aided these studies, requiring simultaneously operation at high input heating power and large energy confinement time (to produce the highest temperature and density), while maintaining low impurity content. The principal limitation to the TFTR fusion power production was the disruptive stability limit. Secondary limitations were the confinement time, and limiter power handling capability. © 1997 IOP Publishing Ltd.

Published
1997

8. Deuterium–tritium plasmas in novel regimes in the Tokamak Fusion Test Reactor

Author

Bell, MG, Batha, S, Beer, M, Bell, RE, Belov, A, Berk, H, Bernabei, S, Bitter, M, Breizman, B, Bretz, NL, Budny, R, Bush, CE, Callen, J, Cauffman, S, Chang, CS, Chang, Z, Cheng, CZ, Darrow, DS, Dendy, RO, Dorland, W, Duong, H, Efthimion, PC, Ernst, D, Evenson, H, Fisch, NJ, Fisher, R, Fonck, RJ, Fredrickson, ED, Fu, GY, Furth, HP, Gorelenkov, NN, Goloborod’ko, V Ya, Grek, B, Grisham, LR, Hammett, GW, Hawryluk, RJ, Heidbrink, W, Herrmann, HW, Herrmann, MC, Hill, KW, Hogan, J, Hooper, B, Hosea, JC, Houlberg, WA, Hughes, M, Jassby, DL, Jobes, FC, Johnson, DW, Kaita, R, Kaye, S, Kesner, J, Kim, JS, Kissick, M, Krasilnikov, AV, Kugel, H, Kumar, A, Lam, NT, Lamarche, P, LeBlanc, B, Levinton, FM, Ludescher, C, Machuzak, J, Majeski, RP, Manickam, J, Mansfield, DK, Mauel, M, Mazzucato, E, McChesney, J, McCune, DC, McKee, G, McGuire, KM, Meade, DM, Medley, SS, Mikkelsen, DR, Mirnov, SV, Mueller, D, Nagayama, Y, Navratil, GA, Nazikian, R, Okabayashi, M, Osakabe, M, Owens, DK, Park, HK, Park, W, Paul, SF, Petrov, MP, Phillips, CK, Phillips, M, Phillips, P, Ramsey, AT, Rice, B, Redi, MH, Rewoldt, G, Reznik, S, Roquemore, AL, Rogers, J, Ruskov, E, Sabbagh, SA, Sasao, M, and Schilling, G

Subjects
Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Classical Physics, Fluids & Plasmas
Abstract

Experiments in the Tokamak Fusion Test Reactor (TFTR) [Phys. Plasmas 2, 2176 (1995)] have explored several novel regimes of improved tokamak confinement in deuterium–tritium (D–T) plasmas, including plasmas with reduced or reversed magnetic shear in the core and high-current plasmas with increased shear in the outer region (high [formula omitted]). New techniques have also been developed to enhance the confinement in these regimes by modifying the plasma-limiter interaction through in situ deposition of lithium. In reversed-shear plasmas, transitions to enhanced confinement have been observed at plasma currents up to 2.2 MA [formula omitted] accompanied by the formation of internal transport barriers, where large radial gradients develop in the temperature and density profiles. Experiments have been performed to elucidate the mechanism of the barrier formation and its relationship with the magnetic configuration and with the heating characteristics. The increased stability of high-current, high-[formula omitted] plasmas produced by rapid expansion of the minor cross section, coupled with improvement in the confinement by lithium deposition has enabled the achievement of high fusion power, up to 8.7 MW, with D–T neutral beam heating. The physics of fusion alpha-particle confinement has been investigated in these regimes, including the interactions of the alphas with endogenous plasma instabilities and externally applied waves in the ion cyclotron range of frequencies. In D–T plasmas with [formula omitted] and weak magnetic shear in the central region, a toroidal Alfvén eigenmode instability driven purely by the alpha particles has been observed for the first time. The interactions of energetic ions with ion Bernstein waves produced by mode conversion from fast waves in mixed-species plasmas have been studied as a possible mechanism for transferring the energy of the alphas to fuel ions. © 1997, American Institute of Physics. All rights reserved.

Published
1997

9. Recent D-T results on TFTR

Author

Johnson, DW, Arunasalam, V, Barnes, CW, Batha, SH, Bateman, G, Beer, M, Bell, MG, Bell, R, Bitter, M, Bretz, NL, Budny, R, Bush, CE, Cauffman, S, Chang, CS, Chang, Z, Cheng, CZ, Darrow, DS, Dendy, R, Dorland, W, Duong, HH, Durst, R, Efthimion, PC, Ernst, D, Evenson, H, Fisch, N, Fisher, R, Fonck, RJ, Fredrickson, E, Fu, GY, Fujita, T, Furth, HP, Gorelenkov, N, Grek, B, Grisham, LR, Hammett, G, Hawryluk, RJ, Heidbrink, W, Herrmann, HW, Hill, KW, Hosea, J, Hsuan, H, Hughes, M, Janos, A, Jassby, DL, Jobes, FC, Johnson, LC, Kamperschroer, J, Kesner, J, Kotschenreuther, M, Kugel, H, Lamarche, PH, Leblanc, B, Levinton, FM, MacHuzak, J, Majeski, R, Mansfield, DK, Marmar, ES, Mazzucato, E, Mauel, M, McChesney, J, McGuire, KM, McKee, G, Meade, DM, Medley, SS, Mikkelsen, DR, Mirnov, SV, Mueller, D, Nazikian, R, Osakabe, M, Owens, DK, Park, H, Park, W, Parks, P, Paul, SF, Petrov, M, Phillips, CK, Phillips, M, Qualls, AL, Ramsey, A, Redi, MH, Rewoldt, G, Roberts, D, Rogers, J, Roquemore, AL, Ruskov, E, Sabbagh, SA, Sasao, M, Schilling, G, Schivell, J, Schmidt, GL, Scott, SD, Semenov, I, Sesnic, S, Skinner, CH, Spong, D, Stratton, BC, Strachan, JD, Stodiek, W, Synakowski, E, and Takahashi, H

Subjects
Fluids & Plasmas, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Other Physical Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics
Abstract

Routine tritium operation in TFTR has permitted investigations of alpha particle physics in parameter ranges resembling those of a reactor core. ICRF wave physics in a DT plasma and the influence of isotopic mass on supershot confinement have also been studied. Continued progress has been made in optimizing fusion power production in TFTR, using extended machine capability and Li wall conditioning. Performance is currently limited by MHD stability. A new reversed magnetic shear regime is being investigated with reduced core transport and a higher predicted stability limit.

Published
1995

10. Plasma-surface interactions in TFTR DT experiments

Author

Owens, DK, Adler, H, Alling, P, Ancher, C, Anderson, H, Anderson, JL, Ashcroft, D, Barnes, Cris W, Barnes, G, Batha, S, Bell, MG, Bell, R, Bitter, M, Blanchard, W, Bretz, NL, Budny, R, Bush, CE, Camp, R, Caorlin, M, Cauffman, S, Chang, Z, Cheng, CZ, Collins, J, Coward, G, Darrow, DS, DeLooper, J, Duong, H, Dudek, L, Durst, R, Efthimion, PC, Ernst, D, Fisher, R, Fonck, RJ, Fredrickson, E, Fromm, N, Fu, GY, Furth, HP, Gentile, C, Gorelenkov, N, Grek, B, Grisham, LR, Hammett, G, Hanson, GR, Hawryluk, RJ, Heidbrink, W, Hermann, HW, Hill, KW, Hosea, J, Hsuan, H, Janos, A, Jassby, DL, Jobes, FC, Johnson, DW, Johnson, LC, Kamperschroer, J, Kugel, H, Lam, NT, LaMarche, PH, Loughlin, MJ, LeBlanc, B, Leonard, M, Levinton, FM, Machuzak, J, Mansfield, DK, Martin, A, Mazzucato, E, Majeski, R, Marmar, E, McChesney, J, McCormack, B, McCune, DC, McGuire, KM, McKee, G, Meade, DM, Medley, SS, Mikkelsen, DR, Mueller, D, Murakami, M, Nagy, A, Nazikian, R, Newman, R, Nishitani, T, Norris, M, O'Connor, T, Oldaker, M, Osakabe, M, Park, H, Park, W, Paul, SF, Pearson, G, Perry, E, Petrov, M, Phillips, CK, Pitcher, S, Raftopoulos, S, Ramsey, A, Rasmussen, DA, Redi, MH, Roberts, D, and Rogers, J

Subjects
Materials Engineering, Energy
Abstract

TFTR has begun its campaign to study deuterium-tritium fusion under reactor-like conditions. Variable amounts of deuterium and tritium neutral beam power have been used to maximize fusion power, study alpha heating, investigate alpha particle confinement, and search for alpha driven plasma instabilities. Additional areas of study include energy and particle transport and confinement, ICRF heating schemes for DT plasmas, tritium retention, and fusion in high βp plasmas. The majority of this work is done in the TFTR supershot confinement regime. To obtain supershots, extensive limiter conditioning using helium fueled ohmic discharges and lithium pellet injection into ohmic and neutral beam heated plasmas is performed, resulting in a low recycling limiter. The relationship between recycling and core plasma confinement has been studied by using helium, deuterium and high-Z gas puffs to simulate high recycling limiter conditions. These studies show that confinement in TFTR supershots is very sensitive to the influx of neutral particles at the plasma edge. © 1995, All rights reserved.

Published
1995

11. Deuterium and tritium experiments on TFTR

Author

Strachan, JD, Adler, H, Barnes, CW, Batha, S, Bell, MG, Bell, R, Bitter, M, Bretz, NL, Budny, R, Bush, CE, Caorlin, M, Chang, Z, Darrow, DS, Duong, H, Durst, R, Efthimion, PC, Fisher, R, Fonck, RJ, Fredrickson, E, Grek, B, Grisham, LR, Hammett, G, Hawryiuk, RJ, Heidbrink, W, Herrmann, HW, Hill, KW, Hosea, J, Hsuan, H, Janos, A, Jassby, DL, Jobes, FC, Johnson, DW, Johnson, LC, Kugel, H, Lam, NT, LeBlanc, B, Levington, FM, Machuzak, J, Mansfield, DK, Mazzucato, E, Majeski, R, Marmar, E, McChesney, J, McGuire, KM, McKee, G, Meade, DM, Medley, SS, Mikkelsen, DR, Mueller, D, Murakami, M, Nazikian, R, Osakabe, M, Owens, DK, Park, H, Paul, SF, Petrov, M, Phillips, CK, Ramsey, AT, Redi, MH, Roberts, D, Rogers, J, Roquemore, AL, Ruskov, E, Sabbagh, SA, Sasao, M, Schilling, G, Schivell, J, Schmidt, GL, Scott, SD, Skinner, CH, Snipes, JA, Stevens, J, Stevenson, T, Stratton, BC, Synakowski, E, Taylor, G, Terry, JL, von Halle, A, von Goeler, S, Wilgen, JB, Wilson, JR, Wong, KL, Wurden, GA, Yamada, M, Young, KM, Zarnstorff, MC, and Zweben, SJ

Subjects
Atomic, Molecular, Nuclear, Particle and Plasma Physics, Other Physical Sciences, Fluids & Plasmas
Abstract

Three campaigns, prior to July 1994, attempted to increase the fusion power in DT plasmas on the Tokamak Fusion Test Reactor (TFTR). The first campaign was dedicated to obtaining >5 MW of fusion power while avoiding MHD events similar to the JET X-event. The second was aimed at producing maximum fusion power irrespective of proximity to MHD limits, and achieved 9 MW limited by a disruption. The third campaign increased the energy confinement time using lithium pellet conditioning while raising the ratio of alpha heating to beam heating.

Published
1994

12. Confinement and heating of a deuterium-tritium plasma

Author

Hawryluk, RJ, Adler, H, Alling, P, Ancher, C, Anderson, H, Anderson, JL, Ashcroft, D, Barnes, Cris W, Barnes, G, Batha, S, Bell, MG, Bell, R, Bitter, M, Blanchard, W, Bretz, NL, Budny, R, Bush, CE, Camp, R, Caorlin, M, Cauffman, S, Chang, Z, Cheng, CZ, Collins, J, Coward, G, Darrow, DS, DeLooper, J, Duong, H, Dudek, L, Durst, R, Efthimion, PC, Ernst, D, Fisher, R, Fonck, RJ, Fredrickson, E, Fromm, N, Fu, GY, Furth, HP, Gentile, C, Gorelenkov, N, Grek, B, Grisham, LR, Hammett, G, Hanson, GR, Heidbrink, W, Herrmann, HW, Hill, KW, Hosea, J, Hsuan, H, Janos, A, Jassby, DL, Jobes, FC, Johnson, DW, Johnson, LC, Kamperschroer, J, Kugel, H, Lam, NT, LaMarche, PH, Loughlin, MJ, LeBlanc, B, Leonard, M, Levinton, FM, Machuzak, J, Mansfield, DK, Martin, A, Mazzucato, E, Majeski, R, Marmar, E, McChesney, J, McCormack, B, McCune, DC, McGuire, KM, McKee, G, Meade, DM, Medley, SS, Mikkelsen, DR, Mueller, D, Murakami, M, Nagy, A, Nazikian, R, Newman, R, Nishitani, T, Norris, M, O’Connor, T, Oldaker, M, Osakabe, M, Owens, DK, Park, H, Park, W, Paul, SF, Pearson, G, Perry, E, Petrov, M, Phillips, CK, Pitcher, S, Ramsey, A, Rasmussen, DA, Redi, MH, Roberts, D, Rogers, J, and Rossmassler, R

Subjects
Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

The Tomamak Fusion Test reactor has performed initial high-power experiments with the plasma fueled with nominally equal densities of deuterium and tritium. Compared to pure deuterium plasmas, the energy stored in the electron and ions increased by ∼20%. These increases indicate improvements in confinement associated with the use of tritium and possibly heating of electrons by α particles created by the D-T fusion reactions. © 1994 The American Physical Society.

Published
1994

13. Fusion power production from TFTR plasmas fueled with deuterium and tritium

Author

Strachan, JD, Adler, H, Alling, P, Ancher, C, Anderson, H, Anderson, JL, Ashcroft, D, Barnes, Cris W, Barnes, G, Batha, S, Bell, MG, Bell, R, Bitter, M, Blanchard, W, Bretz, NL, Budny, R, Bush, CE, Camp, R, Caorlin, M, Cauffman, S, Chang, Z, Cheng, CZ, Collins, J, Coward, G, Darrow, DS, DeLooper, J, Duong, H, Dudek, L, Durst, R, Efthimion, PC, Ernst, D, Fisher, R, Fonck, RJ, Fredrickson, E, Fromm, N, Fu, GY, Furth, HP, Gentile, C, Gorelenkov, N, Grek, B, Grisham, LR, Hammett, G, Hanson, GR, Hawryluk, RJ, Heidbrink, W, Herrmann, HW, Hill, KW, Hosea, J, Hsuan, H, Janos, A, Jassby, DL, Jobes, FC, Johnson, DW, Johnson, LC, Kamperschroer, J, Kugel, H, Lam, NT, LaMarche, PH, Loughlin, MJ, LeBlanc, B, Leonard, M, Levinton, FM, Machuzak, J, Mansfield, DK, Martin, A, Mazzucato, E, Majeski, R, Marmar, E, McChesney, J, McCormack, B, McCune, DC, McGuire, KM, McKee, G, Meade, DM, Medley, SS, Mikkelsen, DR, Mueller, D, Murakami, M, Nagy, A, Nazikian, R, Newman, R, Nishitani, T, Norris, M, O’Connor, T, Oldaker, M, Osakabe, M, Owens, DK, Park, H, Park, W, Paul, SF, Pearson, G, Perry, E, Petrov, M, Phillips, CK, Pitcher, S, Ramsey, AT, Rasmussen, DA, Redi, MH, Roberts, D, and Rogers, J

Subjects
Neurodegenerative, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

Peak fusion power production of 6.2±0.4 MW has been achieved in TFTR plasmas heated by deuterium and tritium neutral beams at a total power of 29.5 MW. These plasmas have an inferred central fusion alpha particle density of 1.2×1017 m-3 without the appearance of either disruptive magnetohydrodynamics events or detectable changes in Alfvén wave activity. The measured loss rate of energetic alpha particles agreed with the approximately 5% losses expected from alpha particles which are born on unconfined orbits. © 1994 The American Physical Society.

Published
1994

14. Preparations for deuterium–tritium experiments on the Tokamak Fusion Test Reactor*

Author

Hawryluk, RJ, Adler, H, Alling, P, Ancher, C, Anderson, H, Anderson, JL, Anderson, JW, Arunasalam, V, Ascione, G, Aschroft, D, Barnes, CW, Barnes, G, Batchelor, DB, Bateman, G, Batha, S, Baylor, LA, Beer, M, Bell, MG, Biglow, TS, Bitter, M, Blanchard, W, Bonoli, P, Bretz, NL, Brunkhorst, C, Budny, R, Burgess, T, Bush, H, Bush, CE, Camp, R, Caorlin, M, Carnevale, H, Chang, Z, Chen, L, Cheng, CZ, Chrzanowski, J, Collazo, I, Collins, J, Coward, G, Cowley, S, Cropper, M, Darrow, DS, Daugert, R, DeLooper, J, Duong, H, Dudek, L, Durst, R, Efthimion, PC, Ernst, D, Faunce, J, Fonck, RJ, Fredd, E, Fredrickson, E, Fromm, N, Fu, GY, Furth, HP, Garzotto, V, Gentile, C, Gettelfinger, G, Gilbert, J, Gioia, J, Goldfinger, RC, Golian, T, Gorelenkov, N, Gouge, MJ, Grek, B, Grisham, LR, Hammett, G, Hanson, GR, Heidbrink, W, Hermann, HW, Hill, KW, Hirshman, S, Hoffman, DJ, Hosea, J, Hulse, RA, Hsuan, H, Jaeger, EF, Janos, A, Jassby, DL, Jobes, FC, Johnson, DW, Johnson, LC, Kamperschroer, J, Kesner, J, Kugel, H, Kwon, S, Labik, G, Lam, NT, LaMarche, PH, Laughlin, MJ, Lawson, E, LeBlanc, B, Leonard, M, Levine, J, Levinton, FM, Loesser, D, Long, D, Machuzak, J, Mansfield, DE, and Marchlik, M

Subjects
Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Classical Physics, Fluids & Plasmas
Abstract

The final hardware modifications for tritium operation have been completed for the Tokamak Fusion Test Reactor (TFTR) [Fusion Technol. 21, 1324 (1992)]. These activities include preparation of the tritium gas handling system, installation of additional neutron shielding, conversion of the toroidal field coil cooling system from water to a Fluorinert™ system, modification of the vacuum system to handle tritium, preparation, and testing of the neutral beam system for tritium operation and a final deuterium-deuterium (D-D) run to simulate expected deuterium-tritium (D-T) operation. Testing of the tritium system with low concentration tritium has successfully begun. Simulation of trace and high power D-T experiments using D-D have been performed. The physics objectives of D-T operation are production of ≈ 10 MW of fusion power, evaluation of confinement, and heating in deuteriumtritium plasmas, evaluation of α-particle heating of electrons, and collective effects driven by alpha particles and testing of diagnostics for confined a particles. Experimental results and theoretical modeling in support of the D-T experiments are reviewed. © 1994 American Institute of Physics.

Published
1994

18. OVERVIEW OF RECENT TFTR RESULTS

Author

ZARNSTORFF, MC, BATEMAN, G, BATHA, SH, BEER, M, BELL, MG, BELL, RE, BIGLARI, H, BITTER, M, BOIVIN, R, BRETZ, NL, BUDNY, RV, BUSH, CE, CALLEN, JD, CHANG, Z, CHEN, L, CHENG, CZ, COWLEY, SC, DARROW, DS, DURST, RD, EFTHIMION, PC, FONCK, RJ, FREDRICKSON, ED, FU, GY, FURTH, HP, GREENE, GJ, GREK, B, GRISHAM, LR, HAMMETT, GW, HAWRYLUK, RJ, HEIDBRINK, WW, HILL, KW, HIRSHMAN, SP, HOFFMAN, DJ, HOSEA, JC, HUGHES, M, HULSE, RA, JANOS, AC, JASSBY, DL, JOBES, FC, JOHNSON, DW, JOHNSON, LC, KAMPERSCHROER, J, KESNER, J, KUGEL, H, LAMARCHE, PH, LEBLANC, B, LEVINTON, F, MACHUZAK, JS, MAJESKI, R, MANOS, DM, MANSFFIELD, DK, MARMAR, ES, MAUEL, ME, MAZZUCATO, E, MCCARTHY, MP, MCCUNE, DC, MCGUIRE, KM, MEADE, DM, MEDLEY, SS, MIKKELSEN, DR, MONTICELLO, DA, MUELLER, D, MURAKAMI, M, MURPHY, J, NAGAYAMA, Y, NAVRATIL, GA, NAZIKIAN, R, OWENS, DK, PARK, HK, PARK, W, PAUL, SF, PERKINS, FW, PERRY, E, PHILLIPS, CK, PHILLIPS, M, PITCHER, S, POMPHREY, N, RASMUSSEN, DA, REDI, MH, REWOLDT, G, RIMINI, F, ROBERTS, D, ROQUEMORE, AL, SABBAGH, SA, SCHILLING, G, SCHIVELL, J, SCHMIDT, GL, SCOTT, SD, SNIPES, JA, STEVENS, JE, STODIEK, W, STRACHAN, JD, STRATTON, BC, SYNAKOWSKI, EJ, TANG, WM, TAYLOR, G, TERRY, JL, THOMPSON, M, TOWNER, HH, and TSUI, H

Published
1993

19. Overview of TFTR transport studies

Author

Hawryluk, RJ, Arunasalam, V, Barnes, CW, Beer, M, Bell, M, Bell, R, Biglari, H, Bitter, M, Boivin, R, Bretz, NL, Budny, R, Bush, CE, Cheng, CZ, Chu, TK, Cohen, SA, Cowley, S, Efhimion, PC, Fonck, RJ, Fredrickson, E, Furth, HP, Goldston, RJ, Greene, G, Grek, B, Grisham, LR, Hammett, G, Heidbrink, W, Hill, KW, Hosea, J, Hulse, RA, Hsuan, H, Janos, A, Jassby, D, Jobes, FC, Johnson, DW, Johnson, LC, Kesner, J, Kieras-Phillips, C, Kilpatrick, SJ, Kugel, H, La Marche, PH, LeBlanc, B, Manos, DM, Mansfield, DK, Marmar, ES, Mazzucato, E, McCarthy, MP, Mauel, M, McCune, DC, McGuire, KM, Meade, DM, Medley, SS, Mikkelsen, DR, Monticello, D, Motley, R, Mueller, D, Nagayama, Y, Navratil, GA, Nazikian, R, Owens, DK, Park, H, Park, W, Paul, S, Perkins, F, Pitcher, S, Ramsey, AT, Redi, MH, Rewoldt, G, Roberts, D, Roquemore, AL, Rutherford, PH, Sabbagh, S, Schilling, G, Schivell, J, Schmidt, GL, Scott, SD, Snipes, J, Stevens, J, Stratton, BC, Stodiek, W, Synakowski, E, Takase, Y, Tang, W, Taylor, G, Terry, J, Timberlake, JR, Towner, HH, Ulrickson, M, Von Goeler, S, Wieland, R, Williams, M, Wilson, JR, Wong, KL, Yamada, M, Yoshikawa, S, Young, KM, Zarnstorff, MC, and Zweben, SJ

Subjects
Fluids & Plasmas, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Other Physical Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics
Abstract

A review of TFTR plasma transport studies is presented. Parallel transport and the confinement of suprathermal ions are found to be relatively well described by theory. Cross-field transport of the thermal plasma, however, is anomalous with the momentum diffusivity being comparable to the ion thermal diffusivity and larger than the electron thermal diffusivity in neutral beam heated discharges. Perturbative experiments have studied nonlinear dependencies in the transport coefficients and examined the role of possible nonlocal phenomena. The underlying turbulence has been studied using microwave scattering, beam emission spectroscopy and microwave reflectometry over a much broader range in k perpendicular to than previously possible. Results indicate the existence of large-wavelength fluctuations correlated with enhanced transport.

Published
1991

31. The impact of lithium wall coatings on NSTX discharges and the engineering of the Lithium Tokamak eXperiment (LTX)

Author

Majeski, R., Kugel, H., Kaita, R., Avasarala, S., Bell, M.G., Bell, R.E., Berzak, L., Beiersdorfer, P., Gerhardt, S.P., Granstedt, E., Gray, T., Jacobson, C., Kallman, J., Kaye, S., Kozub, T., LeBlanc, B.P., Lepson, J., Lundberg, D.P., Maingi, R., Mansfield, D., Paul, S.F., Pereverzev, G.V., Schneider, H., Soukhanovskii, V., Strickler, T., Stotler, D., Timberlake, J., and Zakharov, L.E.

Published
2010
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37. ADDENDUM to EFOMP Policy statement No.14 “The role of the Medical Physicist in the management of safety within the magnetic resonance imaging environment: EFOMP recommendations”

Author

Busoni, S., primary, Bock, M., additional, Chmelik, M., additional, Colgan, N., additional, De Bondt, T., additional, Hanson, L.G., additional, Israel, M., additional, Kugel, H., additional, Maieron, M., additional, Mazzoni, L.N., additional, Seimenis, I., additional, and Vestergaard, P., additional

Published
2021
Full Text
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38. Experimental Results from the TFTR Tokamak

Author

Hawryluk, R. J., Arunasalam, V., Bell, J. D., Bell, M. G., Bitter, M., Blanchard, W. R., Boody, F., Bretz, N., Budny, R., Bush, C. E., Callen, J. D., Cecchi, J. L., Cohen, S., Colchin, R. J., Combs, S. K., Coonrod, J., Davis, S. L., Dimock, D., Dylla, H. F., Efthimion, P. C., Emerson, L. C., England, A. C., Eubank, H. P., Fonck, R., Fredrickson, E., Goldston, R. J., Grisham, L. R., Grek, B., Groebner, R., Hendel, H., Hill, K. W., Hillis, D. L., Hinnov, E., Hiroe, S., Hulse, R., Hsuan, H., Johnson, D., Kaita, R., Kamperschroer, R., Kaye, S. M., Kilpatrick, S., Kugel, H., LaMarche, P. H., Little, R., Ma, C. H., Manos, D. M., Mansfield, D., McCann, R. T., McCarthy, M., McCune, D. C., McGuire, K., Meade, D. M., Medley, S. S., Milora, S. L., Mikkelsen, D. R., Morris, W., Mueller, D., Murakami, M., Nieschmidt, E., Owens, D. K., Pare, V. K., Park, H., Prichard, B., Ramsey, A., Rasmussen, D. A., Redi, M. H., Roquemore, A. L., Sauthoff, N. R., Schivell, J., Schmidt, G. L., Scott, S. D., Sesnic, S., Shimada, M., Simpkins, J. E., Sinnis, J., Stauffer, F., Stratton, B., Tait, G. D., Taylor, G., Thomas, C. E., Towner, H. H., Ulrickson, M., Von Goeler, S., Weiland, R., Wilgen, J. B., Williams, M., Wong, K. L., Yoshikawa, S., Young, K. M., Zarnstorff, M. C., and Zweben, S.

Published
1987

41. Cortical and subcortical neuroanatomical signatures of schizotypy in 3004 individuals assessed in a worldwide ENIGMA study

Author

Kirschner, M, Hodzic-Santor, B, Antoniades, M, Nenadic, I, Kircher, T, Krug, A, Meller, T, Grotegerd, D, Fornito, A, Arnatkeviciute, A, Bellgrove, MA, Tiego, J, Dannlowski, U, Koch, K, Huelsmann, C, Kugel, H, Enneking, V, Klug, M, Leehr, EJ, Boehnlein, J, Gruber, M, Mehler, D, DeRosse, P, Moyett, A, Baune, BT, Green, M, Quide, Y, Pantelis, C, Chan, R, Wang, Y, Ettinger, U, Debbane, M, Derome, M, Gaser, C, Besteher, B, Diederen, K, Spencer, TJ, Fletcher, P, Roessler, W, Smigielski, L, Kumari, V, Premkumar, P, Park, HRP, Wiebels, K, Lemmers-Jansen, I, Gilleen, J, Allen, P, Kozhuharova, P, Marsman, J-B, Lebedeva, I, Tomyshev, A, Mukhorina, A, Kaiser, S, Fett, A-K, Sommer, I, Schuite-Koops, S, Paquola, C, Lariviere, S, Bernhardt, B, Dagher, A, Grant, P, van Erp, TGM, Turner, JA, Thompson, PM, Aleman, A, Modinos, G, Kirschner, M, Hodzic-Santor, B, Antoniades, M, Nenadic, I, Kircher, T, Krug, A, Meller, T, Grotegerd, D, Fornito, A, Arnatkeviciute, A, Bellgrove, MA, Tiego, J, Dannlowski, U, Koch, K, Huelsmann, C, Kugel, H, Enneking, V, Klug, M, Leehr, EJ, Boehnlein, J, Gruber, M, Mehler, D, DeRosse, P, Moyett, A, Baune, BT, Green, M, Quide, Y, Pantelis, C, Chan, R, Wang, Y, Ettinger, U, Debbane, M, Derome, M, Gaser, C, Besteher, B, Diederen, K, Spencer, TJ, Fletcher, P, Roessler, W, Smigielski, L, Kumari, V, Premkumar, P, Park, HRP, Wiebels, K, Lemmers-Jansen, I, Gilleen, J, Allen, P, Kozhuharova, P, Marsman, J-B, Lebedeva, I, Tomyshev, A, Mukhorina, A, Kaiser, S, Fett, A-K, Sommer, I, Schuite-Koops, S, Paquola, C, Lariviere, S, Bernhardt, B, Dagher, A, Grant, P, van Erp, TGM, Turner, JA, Thompson, PM, Aleman, A, and Modinos, G

Abstract

Neuroanatomical abnormalities have been reported along a continuum from at-risk stages, including high schizotypy, to early and chronic psychosis. However, a comprehensive neuroanatomical mapping of schizotypy remains to be established. The authors conducted the first large-scale meta-analyses of cortical and subcortical morphometric patterns of schizotypy in healthy individuals, and compared these patterns with neuroanatomical abnormalities observed in major psychiatric disorders. The sample comprised 3004 unmedicated healthy individuals (12-68 years, 46.5% male) from 29 cohorts of the worldwide ENIGMA Schizotypy working group. Cortical and subcortical effect size maps with schizotypy scores were generated using standardized methods. Pattern similarities were assessed between the schizotypy-related cortical and subcortical maps and effect size maps from comparisons of schizophrenia (SZ), bipolar disorder (BD) and major depression (MDD) patients with controls. Thicker right medial orbitofrontal/ventromedial prefrontal cortex (mOFC/vmPFC) was associated with higher schizotypy scores (r = 0.067, pFDR = 0.02). The cortical thickness profile in schizotypy was positively correlated with cortical abnormalities in SZ (r = 0.285, pspin = 0.024), but not BD (r = 0.166, pspin = 0.205) or MDD (r = -0.274, pspin = 0.073). The schizotypy-related subcortical volume pattern was negatively correlated with subcortical abnormalities in SZ (rho = -0.690, pspin = 0.006), BD (rho = -0.672, pspin = 0.009), and MDD (rho = -0.692, pspin = 0.004). Comprehensive mapping of schizotypy-related brain morphometry in the general population revealed a significant relationship between higher schizotypy and thicker mOFC/vmPFC, in the absence of confounding effects due to antipsychotic medication or disease chronicity. The cortical pattern similarity between schizotypy and schizophrenia yields new insights into a dimensional neurobiological continuity across the extended psychosis phenotype.

Published
2021

42. Neuropeptide S receptor gene — converging evidence for a role in panic disorder

Author

Domschke, K, Reif, A, Weber, H, Richter, J, Hohoff, C, Ohrmann, P, Pedersen, A, Bauer, J, Suslow, T, Kugel, H, Heindel, W, Baumann, C, Klauke, B, Jacob, C, Maier, W, Fritze, J, Bandelow, B, Krakowitzky, P, Rothermundt, M, Erhardt, A, Binder, E B, Holsboer, F, Gerlach, A L, Kircher, T, Lang, T, Alpers, G W, Ströhle, A, Fehm, L, Gloster, A T, Wittchen, H-U, Arolt, V, Pauli, P, Hamm, A, and Deckert, J

Published
2011
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43. Pattern and progression of white-matter changes in a case of posterior cortical atrophy using diffusion tensor imaging

Author

Duning, T., Warnecke, T., Mohammadi, S., Lohmann, H., Schiffbauer, H., Kugel, H., Knecht, S., Ringelstein, E.B., and Deppe, M.

Subjects
Alzheimer's disease -- Case studies, Alzheimer's disease -- Diagnosis, Alzheimer's disease -- Development and progression, Atrophy -- Diagnosis, Atrophy -- Development and progression, Magnetic resonance imaging -- Usage, Health, Psychology and mental health
Published
2009

44. Correction: Widespread white matter microstructural abnormalities in bipolar disorder: evidence from mega- and meta-analyses across 3033 individuals (Neuropsychopharmacology, (2019), 44, 13, (2285-2293), 10.1038/s41386-019-0485-6)

Author

Favre P., Pauling M., Stout J., Hozer F., Sarrazin S., Abe C., Alda M., Alloza C., Alonso-Lana S., Andreassen O. A., Baune B. T., Benedetti F., Busatto G. F., Canales-Rodriguez E. J., Caseras X., Chaim-Avancini T. M., Ching C. R. K., Dannlowski U., Deppe M., Eyler L. T., Fatjo-Vilas M., Foley S. F., Grotegerd D., Hajek T., Haukvik U. K., Howells F. M., Jahanshad N., Kugel H., Lagerberg T. V., Lawrie S. M., Linke J. O., McIntosh A., Melloni E. M. T., Mitchell P. B., Polosan M., Pomarol-Clotet E., Repple J., Roberts G., Roos A., Rosa P. G. P., Salvador R., Sarro S., Schofield P. R., Serpa M. H., Sim K., Stein D. J., Sussmann J. E., Temmingh H. S., Thompson P. M., Verdolini N., Vieta E., Wessa M., Whalley H. C., Zanetti M. V., Leboyer M., Mangin J. -F., Henry C., Duchesnay E., Houenou J., Favre, P., Pauling, M., Stout, J., Hozer, F., Sarrazin, S., Abe, C., Alda, M., Alloza, C., Alonso-Lana, S., Andreassen, O. A., Baune, B. T., Benedetti, F., Busatto, G. F., Canales-Rodriguez, E. J., Caseras, X., Chaim-Avancini, T. M., Ching, C. R. K., Dannlowski, U., Deppe, M., Eyler, L. T., Fatjo-Vilas, M., Foley, S. F., Grotegerd, D., Hajek, T., Haukvik, U. K., Howells, F. M., Jahanshad, N., Kugel, H., Lagerberg, T. V., Lawrie, S. M., Linke, J. O., Mcintosh, A., Melloni, E. M. T., Mitchell, P. B., Polosan, M., Pomarol-Clotet, E., Repple, J., Roberts, G., Roos, A., Rosa, P. G. P., Salvador, R., Sarro, S., Schofield, P. R., Serpa, M. H., Sim, K., Stein, D. J., Sussmann, J. E., Temmingh, H. S., Thompson, P. M., Verdolini, N., Vieta, E., Wessa, M., Whalley, H. C., Zanetti, M. V., Leboyer, M., Mangin, J. -F., Henry, C., Duchesnay, E., and Houenou, J.

Abstract

This Article was originally published under NPG's License to Publish, but has now been made available under a [CC BY 4.0] license. The PDF and HTML versions of the Article have been modified accordingly.

Published
2019

46. Brain structural correlates of alexithymia in patients with major depressive disorder

Author

Förster, K. (Katharina), Enneking, V. (Verena), Dohm, K. (Katharina), Redlich, R. (Ronny), Meinert, S. (Susanne), Geisler, A.I. (Adina), Leehr, E.J. (Elisabeth), Kugel, H. (Harald), Baune, B.T. (Bernhard), Arolt, V. (Volker), Zwitserlood, P. (Pienie), Grotegerd, D. (Dominik), Dannlowski, U. (Udo), and Universitäts- und Landesbibliothek Münster

Subjects
Medicine and health, ddc:610, behavioral disciplines and activities
Abstract

BACKGROUND: Alexithymia is a risk factor for major depressive disorder (MDD) and has been associated with diminished treatment response. Neuroimaging studies have revealed structural aberrations of the anterior cingulate cortex and the fusiform gyrus in healthy controls with high levels of alexithymia. The present study tried to corroborate and extend these results to patients with MDD compared with healthy controls. METHODS: We investigated the relationship between alexithymia, depression and grey matter volume in 63 patients with MDD (mean age ± standard deviation = 42.43 yr ± 11.91; 33 female) and 46 healthy controls (45.35 yr ± 8.37; 22 female). We assessed alexithymia using the Toronto Alexithymia Scale. We conducted an alexithymia × group analysis of covariance; we used a region-of-interest approach, including the fusiform gyrus and anterior cingulate cortex, and conducted whole brain analysis using voxelbased morphometry. RESULTS: Our analysis revealed a significant alexithymia × group interaction in the fusiform gyrus (left, pFWE = 0.031; right, pFWE = 0.010). Higher alexithymia scores were associated with decreased grey matter volume in patients with MDD (pFWE = 0.009), but with increased grey matter volume of the fusiform gyrus in healthy controls (pFWE = 0.044). We found no significant main effects in the region-of-interest analysis. LIMITATIONS: Owing to the naturalistic nature of our study, patients with MDD and healthy controls differed significantly in their alexithymia scores. CONCLUSION: Our results showed the fusiform gyrus as a correlate of alexithymia. We also found differences related to alexithymia between patients with MDD and healthy controls in the fusiform gyrus. Our study encourages research related to the transition from risk to MDD in people with alexithymia.

Published
2020

49. Interactive impact of childhood maltreatment, depression, and age on cortical brain structure: mega-analytic findings from a large multi-site cohort

Author

Tozzi, L, Garczarek, L, Janowitz, D, Stein, DJ, Wittfeld, K, Dobrowolny, H, Lagopoulos, J, Hatton, SN, Hickie, IB, Carballedo, A, Brooks, SJ, Vuletic, D, Uhlmann, A, Veer, IM, Walter, H, Buelow, R, Voelzke, H, Klinger-Koenig, J, Schnell, K, Schoepf, D, Grotegerd, D, Opel, N, Dannlowski, U, Kugel, H, Schramm, E, Konrad, C, Kircher, T, Jueksel, DI, Nenadic, I, Krug, A, Hahn, T, Steinstraeter, O, Redlich, R, Zaremba, D, Zurowski, B, Fu, CHY, Dima, D, Cole, J, Grabe, HJ, Connolly, CG, Yang, TT, Ho, TC, Lewinn, KZ, Li, M, Groenewold, NA, Salminen, LE, Walter, M, Simmons, AN, van Erp, TGM, Jahanshad, N, Baune, BT, van der Wee, NJA, van Tol, M-J, Penninx, BWJH, Hibar, DP, Thompson, PM, Veltman, DJ, Schmaal, L, Frodl, T, Tozzi, L, Garczarek, L, Janowitz, D, Stein, DJ, Wittfeld, K, Dobrowolny, H, Lagopoulos, J, Hatton, SN, Hickie, IB, Carballedo, A, Brooks, SJ, Vuletic, D, Uhlmann, A, Veer, IM, Walter, H, Buelow, R, Voelzke, H, Klinger-Koenig, J, Schnell, K, Schoepf, D, Grotegerd, D, Opel, N, Dannlowski, U, Kugel, H, Schramm, E, Konrad, C, Kircher, T, Jueksel, DI, Nenadic, I, Krug, A, Hahn, T, Steinstraeter, O, Redlich, R, Zaremba, D, Zurowski, B, Fu, CHY, Dima, D, Cole, J, Grabe, HJ, Connolly, CG, Yang, TT, Ho, TC, Lewinn, KZ, Li, M, Groenewold, NA, Salminen, LE, Walter, M, Simmons, AN, van Erp, TGM, Jahanshad, N, Baune, BT, van der Wee, NJA, van Tol, M-J, Penninx, BWJH, Hibar, DP, Thompson, PM, Veltman, DJ, Schmaal, L, and Frodl, T

Abstract

BACKGROUND: Childhood maltreatment (CM) plays an important role in the development of major depressive disorder (MDD). The aim of this study was to examine whether CM severity and type are associated with MDD-related brain alterations, and how they interact with sex and age. METHODS: Within the ENIGMA-MDD network, severity and subtypes of CM using the Childhood Trauma Questionnaire were assessed and structural magnetic resonance imaging data from patients with MDD and healthy controls were analyzed in a mega-analysis comprising a total of 3872 participants aged between 13 and 89 years. Cortical thickness and surface area were extracted at each site using FreeSurfer. RESULTS: CM severity was associated with reduced cortical thickness in the banks of the superior temporal sulcus and supramarginal gyrus as well as with reduced surface area of the middle temporal lobe. Participants reporting both childhood neglect and abuse had a lower cortical thickness in the inferior parietal lobe, middle temporal lobe, and precuneus compared to participants not exposed to CM. In males only, regardless of diagnosis, CM severity was associated with higher cortical thickness of the rostral anterior cingulate cortex. Finally, a significant interaction between CM and age in predicting thickness was seen across several prefrontal, temporal, and temporo-parietal regions. CONCLUSIONS: Severity and type of CM may impact cortical thickness and surface area. Importantly, CM may influence age-dependent brain maturation, particularly in regions related to the default mode network, perception, and theory of mind.

Published
2020

50. Brain structural correlates of alexithymia in patients with major depressive disorder

Author

Foerster, K, Enneking, V, Dohm, K, Redlich, R, Meinert, S, Geisler, AI, Leehr, EJ, Kugel, H, Baune, BT, Arolt, V, Zwitserlood, P, Grotegerd, D, Dannlowski, U, Foerster, K, Enneking, V, Dohm, K, Redlich, R, Meinert, S, Geisler, AI, Leehr, EJ, Kugel, H, Baune, BT, Arolt, V, Zwitserlood, P, Grotegerd, D, and Dannlowski, U

Abstract

BACKGROUND: Alexithymia is a risk factor for major depressive disorder (MDD) and has been associated with diminished treatment response. Neuroimaging studies have revealed structural aberrations of the anterior cingulate cortex and the fusiform gyrus in healthy controls with high levels of alexithymia. The present study tried to corroborate and extend these results to patients with MDD compared with healthy controls. METHODS: We investigated the relationship between alexithymia, depression and grey matter volume in 63 patients with MDD (mean age ± standard deviation = 42.43 yr ± 11.91; 33 female) and 46 healthy controls (45.35 yr ± 8.37; 22 female). We assessed alexithymia using the Toronto Alexithymia Scale. We conducted an alexithymia × group analysis of covariance; we used a region-of-interest approach, including the fusiform gyrus and anterior cingulate cortex, and conducted whole brain analysis using voxelbased morphometry. RESULTS: Our analysis revealed a significant alexithymia × group interaction in the fusiform gyrus (left, pFWE = 0.031; right, pFWE = 0.010). Higher alexithymia scores were associated with decreased grey matter volume in patients with MDD (pFWE = 0.009), but with increased grey matter volume of the fusiform gyrus in healthy controls (pFWE = 0.044). We found no significant main effects in the region-of-interest analysis. LIMITATIONS: Owing to the naturalistic nature of our study, patients with MDD and healthy controls differed significantly in their alexithymia scores. CONCLUSION: Our results showed the fusiform gyrus as a correlate of alexithymia. We also found differences related to alexithymia between patients with MDD and healthy controls in the fusiform gyrus. Our study encourages research related to the transition from risk to MDD in people with alexithymia.

Published
2020

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