Search Results - (Author, Cooperation:A. K. Hansen)

2015-03-15

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

2014-03-29

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

2018-07-03

Genetics Society of America (GSA)

2160-1836

Biology

1089-7674

AIP Digital Archive

Physics

Reduction of core-resonant m=1 magnetic fluctuations and improved confinement in the Madison Symmetric Torus [Dexter et al., Fusion Technol. 19, 131 (1991)] reversed-field pinch have been routinely achieved through control of the surface poloidal electric field, but it is now known that the achieved confinement has been limited in part by edge-resonant m=0 magnetic fluctuations. Now, through refined poloidal electric field control, plus control of the toroidal electric field, it is possible to reduce simultaneously the m=0 and m=1 fluctuations. This has allowed confinement of high-energy runaway electrons, possibly indicative of flux-surface restoration in the usually stochastic plasma core. The electron temperature profile steepens in the outer region of the plasma, and the central electron temperature increases substantially, reaching nearly 1.3 keV at high toroidal plasma current (500 kA). At low current (200 kA), the total beta reaches 15% with an estimated energy confinement time of 10 ms, a tenfold increase over the standard value which for the first time substantially exceeds the constant-beta confinement scaling that has characterized most reversed-field-pinch plasmas. © 2002 American Institute of Physics.

Electronic Resource

1089-7674

AIP Digital Archive

Physics

Locking of a rotating mode by applying a resonant magnetic perturbation having the same helicity has been observed on various devices. Experiments have been carried out on the Madison Symmetric Torus reversed-field pinch (RFP) [Dexter et al., Fusion Technol. 19, 131 (1991)] which show that an externally applied magnetic perturbation can cause locking of the dominant magnetic modes (poloidal mode number m=1, toroidal mode numbers n=5–10) when the perturbation is resonant with them. A perturbation which is not resonant (m=0 or 2) produces no such effect. Thus, resonant torques may lock a stochastic magnetic structure arising from several modes, as likely exists in the RFP, as well as a distinct island as exists in tokamaks, although the details of the interaction are likely to be different. © 1998 American Institute of Physics.

Electronic Resource

1600-0838

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Sports Science

Low muscle glycogen content has been demonstrated to enhance transcription of a number of genes involved in training adaptation. These results made us speculate that training at a low muscle glycogen content would enhance training adaptation. We therefore performed a study in which seven healthy untrained males performed one-knee legged exercise training at a low glycogen (Low) protocol, whereas the other leg was trained at a high glycogen (High) protocol. Both legs were trained equally regarding workload and training amount. Day one: Both legs (Low+High) were trained for 1 h followed by 2 h of rest at a fasting state, where after one leg (Low) was trained for one more hour. Day 2: Only one leg (High) trained for 1 h. Days 1 and 2 were repeated for 10 weeks. As an effect of training, the increase in maximal workload was identical for the two legs. However, time till exhaustion at 90% was markedly more increased in the Low leg compared with the High leg. Resting muscle glycogen and the activity of the mitochondrial enzyme hydroxyacyl CoA dehydrogenase (HAD) increased with training, but only significantly so in LOW, whereas citrate synthase (CS) activity increased in both low and high. There was a more pronounced increase in CS activity when Low was compared with High. In conclusion, the present study suggests that training twice every second day may be superior to daily training.

Electronic Resource

1434-3916

Springer Online Journal Archives 1860-2000

Medicine

Summary Tibial hypo-/aplasia with preaxial syn- and polydactyly is a rare autosomal dominant condition. Fewer than 20 cases have so far been described. One is presented here.

Electronic Resource