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1. Design and methods of the REMOVAL-HD study: a tRial Evaluating Mid cut-Off Value membrane clearance of Albumin and Light chains in HaemoDialysis patients

Author

R. Krishnasamy, C. M. Hawley, M. J. Jardine, M. A. Roberts, Y. J. Cho, M. G. Wong, A. Heath, C. L. Nelson, S. Sen, P. F. Mount, E. M. Pascoe, D. Darssan, L. A. Vergara, P. A. Paul-Brent, N. D. Toussaint, D. W. Johnson, and C. A. Hutchison

Subjects
Albumin, Dialyser, Mid cut-off membrane, Efficacy, Free light chains, Haemodialysis, Diseases of the genitourinary system. Urology, RC870-923
Abstract

Abstract Background Removal of uraemic toxins is inadequate using current dialysis strategies. A new class of dialysis membranes have been developed that allow clearance of larger middle molecules. The REMOVAL-HD study (a tRial Evaluating Mid cut-Off Value membrane clearance of Albumin and Light chains in HaemoDialysis patients) will address safety, efficacy and the impact on patient-centred outcomes with the use of a mid cut-off (MCO) dialyser in a chronic haemodialysis (HD) population. Methods REMOVAL-HD is an open label, prospective, non-randomised, single-arm, multi-centre device study in 85 chronic HD participants. All visits will be conducted during regular HD sessions and participants will undergo a 1 month wash-in period using a standardised high flux dialyser, 6 months of intervention with a MCO dialyser and 1 month of wash-out using a high flux dialyser. The primary endpoint is change in pre-dialysis concentrations of serum albumin, with secondary endpoints including the efficacy of clearance of free light chains and β-2 microglobulin, and patient-centred outcomes including quality of life, symptom burden, functional status, nutritional status, hospitalisation and death. Discussion MCO dialysers are a novel form of HD membrane. The REMOVAL-HD study is a pivotal study designed to monitor the immediate and medium-term effects following exposure to this dialyser. Trial registration Australian New Zealand Clinical Trials Registry Number (ANZCTRN) 12616000804482. Date of registration - 21/06/2016.

Published
2018
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2. Soil carbon and nitrogen erosion in forested catchments: implications for erosion-induced terrestrial carbon sequestration

Author

E. M. Stacy, S. C. Hart, C. T. Hunsaker, D. W. Johnson, and A. A. Berhe

Subjects
Ecology, QH540-549.5, Life, QH501-531, Geology, QE1-996.5
Abstract

Lateral movement of organic matter (OM) due to erosion is now considered an important flux term in terrestrial carbon (C) and nitrogen (N) budgets, yet most published studies on the role of erosion focus on agricultural or grassland ecosystems. To date, little information is available on the rate and nature of OM eroded from forest ecosystems. We present annual sediment composition and yield, for water years 2005–2011, from eight catchments in the southern part of the Sierra Nevada, California. Sediment was compared to soil at three different landform positions from the source slopes to determine if there is selective transport of organic matter or different mineral particle size classes. Sediment export varied from 0.4 to 177 kg ha−1, while export of C in sediment was between 0.025 and 4.2 kg C ha−1 and export of N in sediment was between 0.001 and 0.04 kg N ha−1. Sediment yield and composition showed high interannual variation. In our study catchments, erosion laterally mobilized OM-rich litter material and topsoil, some of which enters streams owing to the catchment topography where steep slopes border stream channels. Annual lateral sediment export was positively and strongly correlated with stream discharge, while C and N concentrations were both negatively correlated with stream discharge; hence, C : N ratios were not strongly correlated to sediment yield. Our results suggest that stream discharge, more than sediment source, is a primary factor controlling the magnitude of C and N export from upland forest catchments. The OM-rich nature of eroded sediment raises important questions about the fate of the eroded OM. If a large fraction of the soil organic matter (SOM) eroded from forest ecosystems is lost during transport or after deposition, the contribution of forest ecosystems to the erosion-induced C sink is likely to be small (compared to croplands and grasslands).

Published
2015
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3. Nutrient and mercury deposition and storage in an alpine snowpack of the Sierra Nevada, USA

Author

C. Pearson, R. Schumer, B. D. Trustman, K. Rittger, D. W. Johnson, and D. Obrist

Subjects
Ecology, QH540-549.5, Life, QH501-531, Geology, QE1-996.5
Abstract

Biweekly snowpack core samples were collected at seven sites along two elevation gradients in the Tahoe Basin during two consecutive snow years to evaluate total wintertime snowpack accumulation of nutrients and pollutants in a high-elevation watershed of the Sierra Nevada. Additional sampling of wet deposition and detailed snow pit profiles were conducted the following year to compare wet deposition to snowpack storage and assess the vertical dynamics of snowpack nitrogen, phosphorus, and mercury. Results show that, on average, organic N comprised 48% of all snowpack N, while nitrate (NO3--N) and TAN (total ammonia nitrogen) made up 25 and 27%, respectively. Snowpack NO3--N concentrations were relatively uniform across sampling sites over the sampling seasons and showed little difference between seasonal wet deposition and integrated snow pit concentrations. These patterns are in agreement with previous studies that identify wet deposition as the dominant source of wintertime NO3--N deposition. However, vertical snow pit profiles showed highly variable concentrations of NO3--N within the snowpack indicative of additional deposition and in-snowpack dynamics. Unlike NO3--N, snowpack TAN doubled towards the end of winter, which we attribute to a strong dry deposition component which was particularly pronounced in late winter and spring. Organic N concentrations in the snowpack were highly variable (from 35 to 70%) and showed no clear temporal, spatial, or vertical trends throughout the season. Integrated snowpack organic N concentrations were up to 2.5 times higher than seasonal wet deposition, likely due to microbial immobilization of inorganic N as evident by coinciding increases in organic N and decreases in inorganic N in deeper, aged snow. Spatial and temporal deposition patterns of snowpack P were consistent with particulate-bound dry deposition inputs and strong impacts from in-basin sources causing up to 6 times greater enrichment at urban locations compared to remote sites. Snowpack Hg showed little temporal variability and was dominated by particulate-bound forms (78% on average). Dissolved Hg concentrations were consistently lower in snowpack than in wet deposition, which we attribute to photochemically driven gaseous re-emission. In agreement with this pattern is a significant positive relationship between snowpack Hg and elevation, attributed to a combination of increased snow accumulation at higher elevations causing limited light penetration and lower photochemical re-emission losses in deeper, higher-elevation snowpack. Finally, estimates of basin-wide loading based on spatially extrapolated concentrations and a satellite-based snow water equivalent reconstruction model identify snowpack chemical loading from atmospheric deposition as a substantial source of nutrients and pollutants to the Lake Tahoe Basin, accounting for 113 t of N, 9.3 t of P, and 1.2 kg of Hg each year.

Published
2015
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4. Nitrogen inputs and losses in response to chronic CO2 exposure in a subtropical oak woodland

Author

B. A. Hungate, B. D. Duval, P. Dijkstra, D. W. Johnson, M. E. Ketterer, P. Stiling, W. Cheng, J. Millman, A. Hartley, and D. B. Stover

Subjects
Ecology, QH540-549.5, Life, QH501-531, Geology, QE1-996.5
Abstract

Rising atmospheric CO2 concentrations may alter the nitrogen (N) content of ecosystems by changing N inputs and N losses, but responses vary in field experiments, possibly because multiple mechanisms are at play. We measured N fixation and N losses in a subtropical oak woodland exposed to 11 years of elevated atmospheric CO2 concentrations. We also explored the role of herbivory, carbon limitation, and competition for light or nutrients in shaping the response of N fixation to elevated CO2. Elevated CO2 did not significantly alter gaseous N losses, but lower recovery and deeper distribution in the soil of a long-term 15N tracer indicated that elevated CO2 increased leaching losses. Elevated CO2 had no effect on nonsymbiotic N fixation, and had a transient effect on symbiotic N fixation by the dominant legume. Elevated CO2 tended to reduce soil and plant concentrations of iron, molybdenum, phosphorus, and vanadium, nutrients essential for N fixation. Competition for nutrients and herbivory likely contributed to the declining response of N fixation to elevated CO2. These results indicate that positive responses of N fixation to elevated CO2 may be transient and that chronic exposure to elevated CO2 can increase N leaching. Models that assume increased fixation or reduced N losses with elevated CO2 may overestimate future N accumulation in the biosphere.

Published
2014
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5. Mercury concentrations and pools in four Sierra Nevada forest sites, and relationships to organic carbon and nitrogen

Author

D. Obrist, D. W. Johnson, and S. E. Lindberg

Subjects
Ecology, QH540-549.5, Life, QH501-531, Geology, QE1-996.5
Abstract

This study presents data on mercury (Hg) concentrations, stochiometric relations to carbon (C) and nitrogen (N), and Hg pool sizes in four Sierra Nevada forest sites of similar exposure and precipitation regimes, and hence similar atmospheric deposition, to evaluate how ecosystem parameters control Hg retention in ecosystems. In all four sites, the largest amounts of Hg reside in soils which account for 94–98% of ecosystem pools. Hg concentrations and Hg/C ratios increase in the following order: Green Needles/Leavesr2=0.58) and N and C (r2=0.64) in decomposing litter, but a positive correlation between litter Hg and N (r2=0.70). These inverse relations may reflect preferential retention of N and Hg over C during decomposition, or may be due to older age of decomposed litter layers which are exposed to longer-term atmospheric Hg deposition in the field. The results indicate that litter Hg levels depend on decomposition stage and may not follow generally observed positive relationships between Hg and organic C. Mineral soil layers show strong positive correlations of Hg to C across all sites and soil horizons (r2=0.83), but Hg concentrations are even more closely related to N with a similar slope to that observed in litter (r2=0.92). Soil N levels alone explain over 90% of Hg pool sizes across the four Sierra Nevada forest sites. This suggests that soil organic N and C groups provide sorption sites for Hg to retain atmospheric deposition. However, the patterns could be due to indirect relationships where high soil N and C levels reflect high ecosystem productivity which leads to corresponding high atmospheric Hg deposition inputs via leaf litterfall and plant senescence. Our results also show that two of the sites previously affected by prescribed burning and wildfires show significant depletion of above-ground Hg pools but that belowground Hg pools remain unaffected. We conclude that sequestration of Hg in remote Sierra Nevada forest sites is strongly co-determined by ecosystem parameters with C and N pools being excellent determinants for the pool sizes of Hg.

Published
2009

6. Is There Synchronicity in Nitrogen Input and Output Fluxes at the Noland Divide Watershed, a Small N-Saturated Forested Catchment in the Great Smoky Mountains National Park?

Author

H. Van Miegroet, I.F. Creed, N.S. Nicholas, D.G. Tarboton, K.L. Webster, J. Shubzda, B. Robinson, J. Smoot, D. W. Johnson, S. E. Lindberg, G. Lovett, S. Nodvin, and S. Moore

Subjects
Technology, Medicine, Science
Abstract

High-elevation red spruce [Picea rubens Sarg.]-Fraser fir [Abies fraseri (Pursh.) Poir] forests in the Southern Appalachians currently receive large nitrogen (N) inputs via atmospheric deposition (30 kg N ha�1 year�1) but have limited N retention capacity due to a combination of stand age, heavy fir mortality caused by exotic insect infestations, and numerous gaps caused by windfalls and ice storms. This study examined the magnitude and timing of the N fluxes into, through, and out of a small, first-order catchment in the Great Smoky Mountains National Park. It also examined the role of climatic conditions in causing interannual variations in the N output signal. About half of the atmospheric N input was exported annually in the streamwater, primarily as nitrate (NO3-N). While most incoming ammonium (NH4-N) was retained in the canopy and the forest floor, the NO3-N fluxes were very dynamic in space as well as in time. There was a clear decoupling between NO3-N input and output fluxes. Atmospheric N input was greatest in the growing season while largest NO3-N losses typically occurred in the dormant season. Also, as water passed through the various catchment compartments, the NO3-N flux declined below the canopy, increased in the upper soil due to internal N mineralization and nitrification, and declined again deeper in the mineral soil due to plant uptake and microbial processing. Temperature control on N production and hydrologic control on NO3-N leaching during the growing season likely caused the observed inter-annual variation in fall peak NO3-N concentrations and N discharge rates in the stream.

Published
2001
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7. Yield-per-Recruit and Relative Mean Biomass Estimates, and their Management Consequences, to the Penaeus Indicus Fishery in the Gulf of Masirah

Author

M. S. M. Siddeek, R. Mohan, and D. W. Johnson

Subjects
marine sciences, Aquaculture. Fisheries. Angling, SH1-691, Agriculture (General), S1-972
Abstract

The von Bertalanffy growth parameters estimated based on the 1990/91 carapace length data of Penaeus indicus from the Gulf of Masirah, Oman were used to calculate total mortality, yield-per-recruit ( i.e. average weight of a shrimp from a cohort under a given fishing pattern) , and relative mean biomass ( i.e. exploited cohort biomass over un-exploited cohort biomass) for the population sampled. The instantaneous total mortality coefficient value indicated under exploitation in 1990/91. When different fishing seasons scenarios were considered with the current total mortality level but with a range of natural mortality values, high yield, per recruit and relative mean biomass values were shown for October-April and November-April fishing seasons. The fishing season is currently late August to end of April. Thus, a one to two-month delay in the fishing season appears to be beneficial to this fishery.

Published
1996
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9. Contributors

Author

James E. Goehring, Janet A. Timbie, and D. W Johnson

Published
2012

12. Bibliography

Author

James E. Goehring, Janet A. Timbie, and D. W Johnson

Published
2012

13. General Index

Author

James E. Goehring, Janet A. Timbie, and D. W Johnson

Published
2012

15. Index to Scripture

Author

James E. Goehring, Janet A. Timbie, and D. W Johnson

Published
2012

18. II. Social Context

Author

James E. Goehring, Janet A. Timbie, and D. W Johnson

Published
2012

25. Abbreviations

Author

James E. Goehring, Janet A. Timbie, and D. W Johnson

Published
2012

27. Introduction

Author

James E. Goehring, Janet A. Timbie, and D. W Johnson

Published
2012

34. Distortion of Chain Conformation and Reduced Entanglement in Polymer-Graphene Oxide Nanocomposites

Author

M P, Weir, D W, Johnson, S C, Boothroyd, R C, Savage, R L, Thompson, S M, King, S E, Rogers, K S, Coleman, and N, Clarke

Abstract

We study the conformations of polymer chains in polymer-graphene oxide nanocomposites. We show that the chains have a reduced radius of gyration that is consistent with confinement at a solid interface in the melt, as is expected for well-dispersed, high aspect ratio nanoparticles that are much larger than the polymer coil size. We show that confinement of the polymer chains causes a corresponding reduction in interchain entanglements, and we calculate a contribution to the plateau modulus from the distorted polymer network via a simple scaling argument. Our results are a significant step forward in understanding how two-dimensional nanoparticles affect global material properties at low loadings.

Published
2022

36. Nitrogen inputs and losses in response to chronic CO2 exposure in a subtropical oak woodland

Author

B. A. Hungate, B. D. Duval, P. Dijkstra, D. W. Johnson, M. E. Ketterer, P. Stiling, W. Cheng, J. Millman, A. Hartley, and D. B. Stover

Subjects
lcsh:Geology, lcsh:QH501-531, lcsh:QH540-549.5, lcsh:QE1-996.5, lcsh:Life, lcsh:Ecology
Abstract

Rising atmospheric CO2 concentrations may alter the nitrogen (N) content of ecosystems by changing N inputs and N losses, but responses vary in field experiments, possibly because multiple mechanisms are at play. We measured N fixation and N losses in a subtropical oak woodland exposed to 11 years of elevated atmospheric CO2 concentrations. We also explored the role of herbivory, carbon limitation, and competition for light or nutrients in shaping the response of N fixation to elevated CO2. Elevated CO2 did not significantly alter gaseous N losses, but lower recovery and deeper distribution in the soil of a long-term 15N tracer indicated that elevated CO2 increased leaching losses. Elevated CO2 had no effect on nonsymbiotic N fixation, and had a transient effect on symbiotic N fixation by the dominant legume. Elevated CO2 tended to reduce soil and plant concentrations of iron, molybdenum, phosphorus, and vanadium, nutrients essential for N fixation. Competition for nutrients and herbivory likely contributed to the declining response of N fixation to elevated CO2. These results indicate that positive responses of N fixation to elevated CO2 may be transient and that chronic exposure to elevated CO2 can increase N leaching. Models that assume increased fixation or reduced N losses with elevated CO2 may overestimate future N accumulation in the biosphere.

Published
2018

37. AKI - experimental models

Author

C.-F. Lai, S.-L. Lin, W.-C. Chiang, Y.-M. Chen, M.-L. Kuo, T.-J. Tsai, H. S. Hwang, Y. A. Choi, K. C. Park, K. J. Yang, H. S. Choi, S. H. Kim, S. J. Lee, Y. K. Chang, S. Y. Kim, C. W. Yang, Z. Xiujuan, R. Yoshimura, M. Matsuyama, J. Chargui, J.-L. Touraine, N. Yoshimura, A. B. Zulkarnaev, I. A. Vasilenko, D. V. Artemov, A. V. Vatazin, S. K. Park, K. P. Kang, S. Lee, W. Kim, R. Schneider, B. Betz, K. Moller-Ehrlich, C. Wanner, C. Sauvant, C. W. Park, R. Sohotnik, O. Nativ, A. Abbasi, H. Awad, V. Frajewicki, Z. Armaly, S. N. Heyman, Z. Abassi, P. Y. Chen, B. L. Chen, C. C. Yang, C. K. Chiang, S. H. Liu, A. E. Abozahra, A. A. Abd-Elkhabir, A. Shokeir, A. Hussein, A. Awadalla, N. Barakat, A. Abdelaziz, J. Yamaguchi, T. Tanaka, N. Eto, M. Nangaku, Y. Quiros, F. J. Lopez-Hernandez, M. P. Perez de Obanos, J. Ruiz, J. M. Lopez-Novoa, H.-S. Shin, M.-J. Kim, Y.-J. Choi, E.-S. Ryu, H.-S. Choi, D.-H. Kang, S. S. Jankauskas, I. B. Pevzner, L. D. Zorova, V. A. Babenko, M. A. Morosanova, E. Y. Plotnikov, D. B. Zorov, C.-Y. Huang, T.-M. Huang, V.-C. Wu, G.-H. Young, A. A. Chupyrkina, S. D. Zorov, J. P. Grande, S. P. Hartono, B. E. Knudsen, K. Mederle, H. Castrop, K. Hocherl, T. Iwakura, T. Fujikura, N. Ohashi, H. Yasuda, Y. Fujigaki, I. Matsui, T. Hamano, K. Inoue, Y. Obi, C. Nakano, Y. Kusunoki, Y. Tsubakihara, H. Rakugi, Y. Isaka, A. Shimomura, C. Wallentin Guron, L. Nguy, J. Lundgren, E. Grimberg, P. Kashioulis, G. Guron, G. F. DiBona, M. Nedergaard Mikkelsen, N. Marcussen, A. Saeed, K. Edvardsson, K. Lindberg, T. Larsson, K. Ito, H. Nakashima, M. Watanabe, Y. Abe, S. Ogahara, T. Saito, G. Albertoni, F. Borges, N. Schor, O. N. Beresneva, M. M. Parastayeva, A. G. Kucher, G. T. Ivanova, N. Shved, M. G. Rybakova, I. G. Kayukov, A. V. Smirnov, J.-F. Chen, H.-F. Ni, M.-M. Pan, H. Liu, M. Xu, M.-H. Zhang, B.-C. Liu, Y. Kim, B. S. Choi, Y. S. Kim, J. S. Han, L. A. Reis, J. S. Christo, M. d. J. Simoes, S. R. Mulay, V. R. Santhosh Kumar, O. P. Kulkarni, M. Darisipudi, M. Lech, H.-J. Anders, D. N. Silachev, A. Sola, M. Jung, M. Ventayol, C. Mastora, S. Buenestado, G. Hotter, S. Rong, N. Shushakova, G. Wensvoort, H. Haller, F. Gueler, C. Morais, D. A. Vesey, D. W. Johnson, G. C. Gobe, M. Godo, T. Kaucsar, C. Revesz, P. Hamar, Q. Cheng, J. Wen, Q. Ma, J. Zhao, G. Castellano, A. Stasi, A. M. Di Palma, M. Gigante, G. S. Netti, C. Curci, A. Intini, C. Divella, C. Prattichizzo, E. Fiaccadori, G. Pertosa, G. Grandaliano, L. Gesualdo, Q. W. Wei, Q. Q. Jing, N. J. Ying, Q. Z. Dong, G. Yong, N. V. Pulkova, G. T. Sukhikh, S. Kim, J. Lee, N. J. Nam, K. Y. Na, S. K. Ma, S. Y. Joo, C. S. Kim, J. S. Choi, E. H. Bae, S. W. Kim, V. Cernaro, M. A. Medici, V. Donato, D. Trimboli, G. Lorenzano, D. Santoro, G. Montalto, M. Buemi, V. Longo, H. R. C. Segreto, W. Almeida, M. F. Ramos, L. Gomes, C. Razvickas, M. Gutberlet, M. Meier, M. Mengel, D. Wacker, K. Hueper, A. Uzum, R. Ersoy, F. Cakalagaoglu, M. Karaman, E. Kolatan, O. Sahin, O. Yilmaz, M. Cirit, S. Inal, E. Koc, G. U. Okyay, O. Pasaoglu, I. Gonul, E. Oyar, H. Pasaoglu, G. Guz, M. Sabbatini, R. Rossano, M. Andreucci, A. Pisani, E. Riccio, D. E. Choi, J. Y. Jeong, S. S. Kim, K.-R. Na, K. W. Lee, Y. T. Shin, A. F. Silva, V. C. Teixeira, K. Meszaros, N. Koleganova-Gut, F. Schaefer, E. Ritz, D. Walacides, N. Ruskamp, M. Schiffer, O. Marom, H. Haick, F. Nakhoul, L.-L. Lv, R.-N. Tang, J.-D. Zhang, K.-L. Ma, P.-S. Chen, W.-J. Ko, G. P. Misiara, T. M. Coimbra, G. E. B. Silva, R. S. Costa, H. D. C. Francescato, M. M. Neto, M. Dantas, H. Olauson, R. Amin, A. Ponnusamy, R. Goetz, M. Mohammadi, A. Canfield, K. Kublickiene, J. Rodriguez, E. P. Reyes, P. P. Cortes, R. Fernandez, H. E. Yoon, E. S. Koh, S. Chung, S. J. Shin, D. Pazzano, R. Lupica, F. Torre, G. Costantino, M. Prieto, J. M. Gonzalez-Buitrago, F. Lopez-Hernandez, A. I. Morales, L. Vicente-Vicente, L. Ferreira, M. J. Simoes, C. d. Passos, N. S. Schor, M. H. M. Shimizu, D. Canale, A. C. de Braganca, L. Andrade, W. M. Luchi, A. C. Seguro, J. Goncalves, R. A. Volpini, P. Garrido, J. Fernandes, S. Ribeiro, H. Vala, B. Parada, R. Alves, L. Belo, E. Costa, A. Santos-Silva, and F. Reis

Subjects
Transplantation, Pathology, medicine.medical_specialty, medicine.anatomical_structure, Nephrology, business.industry, Regeneration (biology), education, medicine, Bone marrow, business, health care economics and organizations
Abstract

Poster presentada en el 50th ERA-EDTA Congress (European Renal Association - European Dialysis Transplant Association), celebrado del 18 al 21 de mayo de 2013 en Estambul (Turquia)

Published
2013
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38. Experimental models of CKD

Author

R. Kanlaya, K. Sintiprungrat, V. Thongboonkerd, N. Torremade, R. Bindels, J. Hoenderop, E. Fernandez, A. Dusso, J. M. Valdivielso, T. Krueger, P. Boor, C. Schafer, R. Westenfeld, V. Brandenburg, G. Schlieper, W. Jahnen-Dechent, M. Ketteler, W. Jee, X. Li, B. Richards, J. Floege, J. G. Goncalves, D. Canale, A. C. de Braganca, M. H. M. Shimizu, R. M. A. Moyses, L. Andrade, A. C. Seguro, R. A. Volpini, S. Romoli, A. Migliorini, H.-J. Anders, O. Eskova, N. Neprintseva, N. Tchebotareva, I. Bobkova, L. Kozlovskaya, I. Simic, M. Tabatabaeifar, T. Wlodkowski, H. Denc, G. Mollet, C. Antignac, F. Schaefer, I. A. Ekaterina, L. Giardino, M. P. Rastaldi, L. Van den Heuvel, E. Levtchenko, C. Okina, T. Okamoto, M. Kamata, J. Murano, K. Kobayashi, K. Takeuchi, F. Kamata, T. Sakai, S. Naito, T. Aoyama, T. Sano, Y. Takeuchi, K. Kamata, D. Thomasova, H. A. Bruns, H. Liapis, T. Iwashita, H. Hasegawa, K. Takayanagi, T. Shimizu, J. Asakura, S. Okazaki, Y. Kogure, M. Hatano, H. Hara, M. Inamura, M. Iwanaga, T. Mitani, T. Mitarai, V. J. Savin, M. Sharma, C. Wei, J. Reiser, E. T. McCarthy, R. Sharma, J.-F. Gauchat, B. Eneman, K. Freson, C. Van Geet, D. E. Choi, J. Y. Jeong, Y. K. Chang, K.-R. Na, K. W. Lee, Y. T. Shin, H.-F. Ni, J.-F. Chen, M.-H. Zhang, M.-M. Pan, B.-C. Liu, S. S. Kim, T. Suzuki, M. Iyoda, K. Matsumoto, Y. Shindo-Hirai, Y. Kuno, Y. Wada, Y. Yamamoto, T. Shibata, T. Akizawa, J. M. Munoz-Felix, J. M. Lopez-Novoa, C. Martinez-Salgado, J. Ehling, J. Babickova, F. Gremse, F. Kiessling, T. Lammers, M. Lech, R. Gunthner, G. Lorenz, M. Ryu, R. Grobmayr, H. Susanti, K. S. Kobayashi, R. A. Flavell, S. Rayego-Mateos, J. Morgado, A. B. Sanz, S. Eguchi, J. Pato, G. Keri, J. Egido, A. Ortiz, M. Ruiz-Ortega, M. Leduc, L. Geerts, B. Grouix, F. Sarra-Bournet, A. Felton, L. Gervais, S. Abbott, J.-S. Duceppe, B. Zacharie, C. Penney, P. Laurin, L. Gagnon, M. G. Detsika, P. Duann, E. A. Lianos, K. I. Leong, C.-K. Chiang, C.-C. Yang, C.-T. Wu, L.-P. Chen, K.-Y. Hung, S.-H. Liu, F. F. Carvalho, V. P. Teixeira, W. S. Almeida, N. Schor, D. M. Small, N. C. Bennett, J. Coombes, D. W. Johnson, G. C. Gobe, N. Montero, A. Prada, M. Riera, M. Orfila, J. Pascual, E. Rodriguez, C. Barrios, G. Kokeny, K. Fazekas, L. Rosivall, M. M. Mozes, N. Hornigold, J. Hughes, A. Mooney, A. Benardeau, W. Riboulet, A. Vandjour, B. Jacobsen, C. Apfel, K. Conde-Knape, J.-F. Bienvenu, T. Tanaka, J. Yamaguchi, M. Nangaku, T. Niwa, D. Bolati, H. Shimizu, M. Yisireyili, F. Nishijima, A. Brocca, G. Virzi, M. de Cal, C. Ronco, G. Priante, E. Musacchio, C. Valvason, L. Sartori, A. Piccoli, B. Baggio, M. Perkuhn, M. Weibrecht, S. Zok, I. V. Martin, F. Schoth, T. Ostendorf, C. Kuhl, A. Karabaeva, A. Essaian, O. Beresneva, M. Parastaeva, I. Kayukov, A. Smirnov, I. Audzeyenka, M. Kasztan, A. Piwkowska, D. Rogacka, S. Angielski, M. Jankowski, C. L. Bockmeyer, K. Kokowicz, P. A. Agustian, S. Zell, J. Wittig, J. U. Becker, R. Nishizono, M. P. Venkatareddy, M. A. Chowdhury, S. Q. Wang, A. Fukuda, L. T. Wickman, Y. Yang, R. C. Wiggins, M. R. Fazio, V. Donato, S. Lucisano, V. Cernaro, R. Lupica, D. Trimboli, G. Montalto, C. Aloisi, A. T. Mazzeo, M. Buemi, O. Gawrys, K. H. Olszynski, M. Kuczeriszka, K. Gawarecka, E. Swiezewska, M. Chmielewski, M. Masnyk, J. Rafalowska, E. Kompanowska-Jezierska, W.-C. Lee, Y.-Y. Chau, L.-C. Lee, C.-H. Chiu, C.-T. Lee, J.-B. Chen, W.-K. Kim, and S. J. Shin

Subjects
Transplantation, medicine.medical_specialty, Nephrology, business.industry, Medicine, business, Intensive care medicine
Published
2013
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39. Epidemiology and outcome research in CKD 5D

Author

L. Coentrao, C. Ribeiro, C. Santos-Araujo, R. Neto, M. Pestana, W. Kleophas, A. Karaboyas, Y. LI, J. Bommer, R. Pisoni, B. Robinson, F. Port, G. Celik, B. Burcak Annagur, M. Yilmaz, T. Demir, F. Kara, K. Trigka, P. Dousdampanis, N. Vaitsis, S. Aggelakou-Vaitsi, K. Turkmen, I. Guney, F. Turgut, L. Altintepe, H. Z. Tonbul, E. Abdel-Rahman, P. Sclauzero, G. Galli, G. Barbati, M. Carraro, G. O. Panzetta, M. Van Diepen, M. Schroijen, O. Dekkers, F. Dekker, A. Sikole, G. Severova- Andreevska, L. Trajceska, S. Gelev, V. Amitov, S. Pavleska- Kuzmanovska, H. Rayner, R. Vanholder, M. Hecking, B. Jung, M. Leung, F. Huynh, T. Chung, S. Marchuk, M. Kiaii, L. Er, R. Werb, C. Chan-Yan, M. Beaulieu, P. Malindretos, P. Makri, G. Zagkotsis, G. Koutroumbas, G. Loukas, E. Nikolaou, M. Pavlou, E. Gourgoulianni, M. Paparizou, M. Markou, E. Syrgani, C. Syrganis, J. Raimann, L. A. Usvyat, V. Bhalani, N. W. Levin, P. Kotanko, X. Huang, P. Stenvinkel, A. R. Qureshi, U. Riserus, T. Cederholm, P. Barany, O. Heimburger, B. Lindholm, J. J. Carrero, J. H. Chang, J. Y. Sung, J. Y. Jung, H. H. Lee, W. Chung, S. Kim, J. S. Han, K. Y. Na, A. Fragoso, A. Pinho, A. Malho, A. P. Silva, E. Morgado, P. Leao Neves, N. Joki, Y. Tanaka, M. Iwasaki, S. Kubo, T. Hayashi, Y. Takahashi, K. Hirahata, Y. Imamura, H. Hase, C. Castledine, J. Gilg, C. Rogers, Y. Ben-Shlomo, F. Caskey, J. S. Sandhu, G. S. Bajwa, S. Kansal, J. Sandhu, A. Jayanti, M. Nikam, L. Ebah, A. Summers, S. Mitra, J. Agar, A. Perkins, R. Simmonds, A. Tjipto, S. Amet, V. Launay-Vacher, M. Laville, A. Tricotel, C. Frances, B. Stengel, J.-Y. Gauvrit, N. Grenier, G. Reinhardt, O. Clement, N. Janus, L. Rouillon, G. Choukroun, G. Deray, A. Bernasconi, R. Waisman, A. P. Montoya, A. A. Liste, R. Hermes, G. Muguerza, R. Heguilen, E. L. Iliescu, V. Martina, M. A. Rizzo, P. Magenta, L. Lubatti, G. Rombola, M. Gallieni, C. Loirat, H. Mellerio, M. Labeguerie, B. Andriss, E. Savoye, M. Lassale, C. Jacquelinet, C. Alberti, Y. Aggarwal, J. Baharani, S. Tabrizian, S. Ossareh, M. Zebarjadi, P. Azevedo, F. Travassos, I. Frade, M. Almeida, J. Queiros, F. Silva, A. Cabrita, R. Rodrigues, C. Couchoud, J. Kitty, S. Benedicte, C. Fergus, C. Cecile, B. Sahar, V. Emmanuel, J. Christian, E. Rene, H. Barahimi, M. Mahdavi-Mazdeh, M. Nafar, M. Petruzzi, M. De Benedittis, M. Sciancalepore, L. Gargano, P. Natale, M. C. Vecchio, V. Saglimbene, F. Pellegrini, G. Gentile, P. Stroumza, L. Frantzen, M. Leal, M. Torok, A. Bednarek, J. Dulawa, E. Celia, R. Gelfman, J. Hegbrant, C. Wollheim, S. Palmer, D. W. Johnson, P. J. Ford, J. C. Craig, G. F. Strippoli, M. Ruospo, B. El Hayek, B. Hayek, E. Baamonde, E. Bosch, J. I. Ramirez, G. Perez, A. Ramirez, A. Toledo, M. M. Lago, C. Garcia-Canton, M. D. Checa, B. Canaud, B. Lantz, A. Granger-Vallee, P. Lertdumrongluk, N. Molinari, J. Ethier, M. Jadoul, B. Gillespie, C. Bond, S. Wang, T. Alfieri, P. Braunhofer, B. Newsome, M. Wang, B. Bieber, M. Guidinger, L. Zuo, X. Yu, X. Yang, J. Qian, N. Chen, J. Albert, Y. Yan, S. Ramirez, M. Beresan, A. Lapidus, M. Canteli, A. Tong, B. Manns, J. Craig, G. Strippoli, M. Mortazavi, B. Vahdatpour, S. Shahidi, A. Ghasempour, D. Taheri, S. Dolatkhah, A. Emami Naieni, M. Ghassami, M. Khan, K. Abdulnabi, P. Pai, M. Vecchio, M. A. Muqueet, M. J. Hasan, M. A. Kashem, P. K. Dutta, F. X. Liu, L. Noe, T. Quock, N. Neil, G. Inglese, M. Motamed Najjar, B. Bahmani, A. Shafiabadi, J. Helve, M. Haapio, P.-H. Groop, C. Gronhagen-Riska, P. Finne, R. Sund, M. Cai, S. Baweja, A. Clements, A. Kent, R. Reilly, N. Taylor, S. Holt, L. Mcmahon, M. Carter, F. M. Van der Sande, J. Kooman, R. Malhotra, G. Ouellet, E. L. Penne, S. Thijssen, M. Etter, A. Tashman, A. Guinsburg, A. Grassmann, C. Barth, C. Marelli, D. Marcelli, G. Von Gersdorff, I. Bayh, L. Scatizzi, M. Lam, M. Schaller, T. Toffelmire, Y. Wang, P. Sheppard, L. Neri, V. A. Andreucci, L. A. Rocca-Rey, S. V. Bertoli, D. Brancaccio, G. De Berardis, G. Lucisano, D. Johnson, A. Nicolucci, C. Bonifati, S. D. Navaneethan, V. Montinaro, M. Zsom, A. Bednarek-Skublewska, G. Graziano, J. N. Ferrari, A. Santoro, A. Zucchelli, G. Triolo, S. Maffei, S. De Cosmo, V. M. Manfreda, L. Juillard, A. Rousset, F. Butel, S. Girardot-Seguin, T. Hannedouche, M. Isnard, Y. Berland, P. Vanhille, J.-P. Ortiz, G. Janin, P. Nicoud, M. Touam, E. Bruce, B. Grace, P. Clayton, A. Cass, S. Mcdonald, Y. Furumatsu, T. Kitamura, N. Fujii, S. Ogata, H. Nakamoto, K. Iseki, Y. Tsubakihara, C.-C. Chien, J.-J. Wang, J.-C. Hwang, H.-Y. Wang, W.-C. Kan, N. Kuster, L. Patrier, A.-S. Bargnoux, M. Morena, A.-M. Dupuy, S. Badiou, J.-P. Cristol, J.-M. Desmet, V. Fernandes, F. Collart, N. Spinogatti, J.-M. Pochet, M. Dratwa, E. Goffin, J. Nortier, D. S. Zilisteanu, M. Voiculescu, E. Rusu, C. Achim, R. Bobeica, S. Balanica, T. Atasie, S. Florence, S. Anne-Marie, L. Michel, C. Cyrille, A. Strakosha, N. Pasko, S. Kodra, N. Thereska, A. Lowney, E. Lowney, R. Grant, M. Murphy, L. Casserly, T. O' Brien, W. D. Plant, J. Radic, D. Ljutic, V. Kovacic, M. Radic, K. Dodig-Curkovic, M. Sain, I. Jelicic, T. Hamano, C. Nakano, S. Yonemoto, A. Okuno, M. Katayama, Y. Isaka, M. Nordio, A. Limido, M. Postorino, M. Nichelatti, M. Khil, I. Dudar, V. Khil, I. Shifris, M. Momtaz, A. R. Soliman, M. I. El Lawindi, P. Dzekova-Vidimliski, S. Pavleska-Kuzmanovska, I. Nikolov, G. Selim, T. Shoji, R. Kakiya, N. Tatsumi-Shimomura, Y. Tsujimoto, T. Tabata, H. Shima, K. Mori, S. Fukumoto, H. Tahara, H. Koyama, M. Emoto, E. Ishimura, Y. Nishizawa, and M. Inaba

Subjects
Transplantation, medicine.medical_specialty, Nephrology, business.industry, Epidemiology, Medicine, business, Intensive care medicine, Outcome (game theory)
Published
2012
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40. Premature Decline of Eucalyptus and Altered Ecosystem Processes in the Absence of Fire in Some Australian Forests

Author

Bryony M. Horton, D. W. Johnson, R.D. Archibald, Marc D. Abrams, Neil J. Davidson, Dugald C. Close, Ian D. Lunt, Mark A. Adams, and S. C. Hart

Subjects
Plant ecology, Biomass (ecology), Geography, Fire regime, Agroforestry, Ecology, Litter, Biodiversity, Ecosystem, Plant Science, Woodland, Vegetation, Ecology, Evolution, Behavior and Systematics
Abstract

We propose a model of ‘premature tree decline’ whereby an absence of fire hastens the mortality of overstorey eucalypts in some forests. This model is relevant to some temperate Australian forests in which fire regimes have shifted from relatively frequent before European settlement to infrequent following settlement. The increased development of midstorey vegetation and litter accumulation has occurred since European settlement in some specific examples of Australian forests and woodlands. Our model proposes that in the long absence of fire: 1. midstorey vegetation reduces the availability of soil water for eucalypts and; 2. Eucalypts have less access to P and/or cations as these elements become locked up in soil, litter and midstorey biomass. We highlight important knowledge gaps and argue that research into ecological burning, for eucalypt health and other values such as biodiversity, is urgently required.

Published
2009
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41. Editorial Perspectives - Chapter 13: Challenges in Fusion Diagnostic Development: A Virtual Tour of ITER

Author

A. E. Costley and D. W. Johnson

Subjects
Nuclear and High Energy Physics, Virtual tour, 020209 energy, Mechanical Engineering, Nanotechnology, 02 engineering and technology, 01 natural sciences, 010305 fluids & plasmas, Development (topology), Nuclear Energy and Engineering, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Systems engineering, General Materials Science, Civil and Structural Engineering
Abstract

The physics basis for almost all the diagnostics planned for ITER is reasonably well in hand. However, the radiation environment near the ITER plasma creates unique challenges for diagnostic engine...

Published
2008
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42. Fabrication of pure silica films for planar optical waveguides using colloidal suspensions

Author

Glen R. Kowach, Suhas Bhandarkar, Henry Du, D. W. Johnson, and Deok-Yang Kim

Subjects
Tetramethylammonium hydroxide, Materials science, Fabrication, Silicon, business.industry, chemistry.chemical_element, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, Suspension (chemistry), chemistry.chemical_compound, Optics, Chemical engineering, chemistry, Materials Chemistry, Ceramics and Composites, Wafer, business, Porosity, Refractive index, Fumed silica
Abstract

In this work, colloidal suspensions are used as a precursor to the formation of layers of optical quality glass on silicon substrates. The colloidal suspensions were made by dispersing a high concentration of fumed silica (particle diameter of 40 ± 30 nm) in water with tetramethylammonium hydroxide (TMAH) as a base to stabilize the suspension. Spin-coating was used as the film deposition method to prepare porous silica films. These films were then consolidated at 1300 °C in an atmosphere of helium and oxygen. Dense silica films with thicknesses up to 1.4 μm could be made this way from a single spin-coating step. The refractive index, as measured by reflectometry, of the densified film at a wavelength of 632.8 nm is 1.4577 ± 0.0005. This is comparable to that of a thermal oxide on a silicon wafer confirming that the film is fully densified. Also, fully dense, defect-free films with thicknesses in the order of 10 μm were fabricated with multiple spin-coating steps to meet the dimensional requirements of planar optical waveguides.

Published
2004
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44. Inhibition of NMDA-induced striatal dopamine release and behavioral activation by the neuroactive steroid 3α-hydroxy-5β-pregnan-20-one hemisuccinate

Author

David H. Farb, Ghazaleh Sadri-Vakili, R. C. Pierce, D. W. Johnson, Terrell T. Gibbs, and G. C. Janis

Subjects
medicine.medical_specialty, Microdialysis, Neuroactive steroid, Striatum, Biochemistry, Neuroprotection, Cellular and Molecular Neuroscience, chemistry.chemical_compound, Endocrinology, medicine.anatomical_structure, nervous system, chemistry, Dopamine, Internal medicine, Neuromodulation, medicine, NMDA receptor, Neurotransmitter, medicine.drug
Abstract

Our laboratory has previously shown that the synthetic neuroactive steroid 3α-hydroxy-5β-pregnan-20-one hemisuccinate (3α5βHS) is a negative modulator of NMDA receptors in vitro. Similarly, 3α5βHS exhibits rapid sedative, analgesic, anticonvulsive, and neuroprotective effects in vivo. Here we report a study designed to investigate whether a negatively charged neuroactive steroid, 3α5βHS, modulates the action of NMDA receptors in vivo. Our results indicate that peripherally administered 3α5βHS enters the CNS and inhibits NMDA-mediated motor activity and dopamine release in the rat striatum. The increase in motor activity induced by intrastriatal microinjection of NMDA was blocked by the systemic administration of 3α5βHS and the NMDA-induced increase in extracellular dopamine in the striatum was also attenuated by both systemically administered and intrastriatally administered (by in vivo microdialysis) 3α5βHS. These data indicate that 3α5βHS acts through striatal NMDA receptors in vivo. When taken together, these results suggest that neuroactive steroids may prove to be effective in the treatment of neurological and psychiatric disorders involving over-stimulation of NMDA receptors in the mesotelencephalic dopamine system.

Published
2004
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45. New Directions in Fusion Plasma Diagnostic Development

Author

D. W. Johnson

Subjects
Nuclear physics, Nuclear and High Energy Physics, Development (topology), Nuclear Energy and Engineering, Mechanical Engineering, Plasma turbulence, Fusion plasma, Systems engineering, Plasma confinement, General Materials Science, Close coupling, Civil and Structural Engineering
Abstract

Diagnostic development is an important and vital part of the fusion program. There is close coupling between the physics needs for measurements and the diagnostic development that receives funding. This paper gives brief technical descriptions of ongoing developments in a few areas currently receiving attention. These areas include T{sub e} diagnostics, j(R) diagnostics applicable to new regimes, and diagnostics to probe edge and core turbulence. The underlying physics motivation and enabling technologies involved in these developments are also mentioned. A brief status of diagnostic work in support of a burning plasma experiment (BPX) is also described, since this effort may become more significant worldwide. Several diagnostic R and D topics, identified as crucial for a BPX, are discussed.

Published
2003
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46. Recent results from the National Spherical Torus Experiment

Author

R Maingi, M G Bell, R E Bell, J Bialek, C Bourdelle, C E Bush, D S Darrow, E D Fredrickson, D A Gates, M Gilmore, T Gray, T R Jarboe, D W Johnson, R Kaita, S M Kaye, S Kubota, H W Kugel, B P LeBlanc, R J Maqueda, D Mastrovito, S S Medley, J E Menard, D Mueller, B A Nelson, M Ono, F Paoletti, H K Park, S F Paul, T Peebles, Y-K M Peng, C K Phillips, R Raman, A L Rosenberg, A L Roquemore, P M Ryan, S A Sabbagh, C H Skinner, V A Soukhanovskii, D Stutman, D W Swain, E J Synakowski, G Taylor, J Wilgen, J R Wilson, G A Wurden, S J Zweben, and the NSTX Team

Subjects
Physics, Tokamak, Divertor, Nuclear engineering, Magnetic confinement fusion, Torus, Condensed Matter Physics, Helicity, law.invention, Nuclear physics, Nuclear Energy and Engineering, Heat flux, law, Current (fluid), Coaxial
Abstract

The National Spherical Torus Experiment (NSTX) is a low aspect-ratio fusion research facility whose research goal is to make a determination of the attractiveness of the spherical torus concept in the areas of high-β stability, confinement, current drive, and divertor physics. Remarkable progress was made in extending the operational regime of the device in FY 2002. In brief, βt of 34% and βN of 6.5 were achieved. H-mode became the main operational regime, and energy confinement exceeded conventional aspect-ratio tokamak scalings. Heating was demonstrated with the radiofrequency antenna, and signatures of current drive were observed. Current initiation with coaxial helicity injection produced discharges of 400 kA, and first measurements of divertor heat flux profiles in H-mode were made.

Published
2003
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47. Small-angle neutron scattering studies on binary mixtures of polystyrene and perfluorinated particles

Author

Ronald H. Ottewill, G. D. W. Johnson, and A. R. Rennie

Subjects
Materials science, Dispersity, Surfaces and Interfaces, Neutron scattering, Radial distribution function, Molecular physics, Small-angle neutron scattering, Crystallography, chemistry.chemical_compound, Colloid and Surface Chemistry, chemistry, Cluster (physics), Polystyrene, Physical and Theoretical Chemistry, Dispersion (chemistry), Structure factor
Abstract

Small-angle neutron scattering measurements (SANS) studies have been carried out on binary mixtures of small polystyrene particles (radius 315 A) and larger perfluorinated particles (radius 664 A). Both types of particles were spherical, monodisperse and negatively charged in the aqueous conditions used. Electrostatic interactions between the particles in each type of dispersion were examined by determining the structure factor of the dispersions. Good agreement with the experimental data and theory were obtained with the rescaled mean-spherical-approximation-model (RMSA). An alternative approach for predicting the structure factor using an equivalent hard-sphere model also gave good agreement with the experimental data. In the case of binary mixtures, with the FEP particles contrast matched, the radial distribution function indicated extensive ordering of the polystyrene particles. In addition there was evidence, at high number ratios of small particles, of cluster formation of small particles with some rejection of these from the ordered arrangement.

Published
2003
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49. Ion exchange resin based soil solution lysimeters and snowmelt solution collectors

Author

D. W. Johnson and R. B. Susfalk

Subjects
Hydrology, Inceptisol, Phosphorus, Soil Science, Mineralogy, chemistry.chemical_element, Nitrogen, chemistry.chemical_compound, Flux (metallurgy), chemistry, Snowmelt, Lysimeter, Ammonium, Ion-exchange resin, Agronomy and Crop Science
Abstract

Conventional soil solution lysimeters and snowmelt solution collectors suffer from a number of limitations when used to estimate yearly nutrient fluxes. This study describes an alternative technique to directly measure soil and snowmelt solution fluxes utilizing ion exchange resin-based collectors. Resin-lysimeters were constructed by enclosing a layer of resin between two layers of nutrient-free silica sand within a polyvinyl chloride tube. Nitrogen (N) and phosphorus (P) fluxes from resin based collectors were compared against buried resin bags, ceramic cup lysimeters, and traditional snowmelt solution collectors co-located in an eastern Sierra Nevada forest. Ammonium and P accumulation in resin lysimeters were one- to two orders of magnitude smaller than in buried resin bags placed in direct contact with the soil. Resin lysimeters and resin snowmelt collectors measured NH4–N and P fluxes that were three times greater than those estimated from ceramic cup lysimeters and solution snowmelt collectors. We ...

Published
2002
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50. Initial studies of core and edge transport of NSTX plasmas

Author

E J Synakowski, M G Bell, R E Bell, C E Bush, C Bourdelle, D Darrow, W Dorland, A Ejiri, E D Fredrickson, D A Gates, S M Kaye, S Kubota, H W Kugel, B P LeBlanc, R Maingi, R J Maqueda, J E Menard, D Mueller, A Rosenberg, S A Sabbagh, D Stutman, G Taylor, D W Johnson, R Kaita, M Ono, F Paoletti, W Peebles, Y-K M Peng, A L Roquemore, C H Skinner, V A Soukhanovskii, and the NSTX Research Team

Subjects
Physics, Nuclear Energy and Engineering, Physics::Plasma Physics, Magnetic confinement fusion, Electron temperature, Plasma diagnostics, Plasma, Electron, Atomic physics, Condensed Matter Physics, Thermal conduction, Neutral beam injection, Ion
Abstract

Rapidly developing diagnostic, operational, and analysis capability is enabling the first detailed local physics studies to begin in high β plasmas of the National Spherical Torus Experiment (NSTX). These studies are motivated in part by the observation of energy confinement times in neutral-beam-heated discharges that are favourable with respect to predictions from the ITER-89P scaling expression. For plasmas heated with neutral beam injection (NBI), analysis based on profile measurements suggests that electron heat conduction is the dominant thermal loss channel. Cases where early analysis indicates that ion thermal conduction may be exceptionally low is motivating studies of possible sources of ion heating not presently accounted for by classical collisional processes. Gyrokinetic microstability studies indicate that long wavelength turbulence with kθρi~0.1-1 may be stable or suppressed by E×B shear in these plasmas, while modes with kθρi~50 may be robust. High harmonic fast wave (HHFW) heating efficiently heats electrons on NSTX, and studies have begun using it to assess transport in the electron channel. Regarding edge transport, H-mode transitions occur with either NBI or HHFW heating. The power required for L- to H-mode transitions far exceeds that expected from empirical ELM-free H-mode scaling laws derived from moderate aspect ratio devices. Finally, initial fluctuation measurements made with two techniques are permitting the first characterizations of edge turbulence.

Published
2002
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