Oral temperature data were collected from 12 members of the crew of an oil tanker at sea. Most of the personnel examined were engaged on watchkeeping duties on a '4 on, 8 off' fixed-hours system; the remainder included 3 "day-workers". The study commenced after the subjects had been following their particular work schedules continuously for several weeks, thus providing good opportunity for adaptation to them. Observations were made at 4-hourly intervals during waking hours, over a period ranging from 8 to 13 days in individual cases. The form of the mean curves produced by averaging the readings over all days indicated that a reasonable degree of adjustment of the temperature rhythm to the different sleep/wake routines imposed by the work system had occurred. Estimates of rhythm phase and amplitude obtained by "single cosinor" time series analyses of the sequential data supported this impression. However, further investigations are needed to substantiate these findings, and also to determine how long it takes for the rhythm adjustment process to reach completion in inexperienced workers.
Princeton's Tokamak Fusion Test Reactor (TFTR) is the rst experimental fusion device to routinely use tritium to study the deuterium-tritium (DT) fusion reaction, allowing the rst systematic study of DT alpha () particles in tokamak plasmas. A crucial aspect of {particle physics is the fraction of alphas that escape from the plasma, particularly since these energetic particles can do severe damage to the rst wall of a reactor.An escaping alpha collector probe has been developed for TFTR's DT phase. Energy distributions of escaping alphas have been determined by measuring the range of {particles implanted into nickel foils located within the alpha collector. Results at 1.0 MA of plasma current are in good agreement with predictions for rst orbit alpha loss. Results at 1.8 MA, however, show a signicant anomalous loss of partially thermalized alphas (in addition to the expected rst orbit loss), which i s n o t observed with the lost alpha scintillator detectors in DT plasmas, but does resemble the anomalous`delayed' loss seen in DD plasmas. None of the candidate explanations proposed thus far are fully consistent with the anomalous loss observations. An experiment designed to study the eect of plasma major radius shifts on { particle loss has led to a better understanding of {particle dynamics in tokamaks. Intuitively, one might suppose that conned marginally passing {particles forced to move t o w ard higher magnetic eld during an inward major radius shift (i.e. compression) would mirror and become trapped particles, leading to increased alpha loss. Such an eect was looked for during the shift experiment, however, no signicant changes in alpha loss to the 90 lost alpha scintillator detector were observed during iii the shifts. It is calculated that the energy gained by a n {particle during the inward shift is sucient to explain this result. However, an unexpected loss of partially thermalized {particles near the passing/trapped boundary was observed to occur between inward and outward shifts at an intermediate value of plasma current (1.4 MA). This anomalous loss feature is not yet understood.iv Acknowledgments Very special thanks go to my advisor, Dr. Stewart J. Zweben, who provided endless advice and guidance. Needless to say, without his support this work would not have been possible. Of course there are many others who have contributed to this eort. In particular, I would like to thank Doug Darrow, the other third of the`Lost Alpha Team', for his valuable insights. Two others, who were very close to this project, but were unfortunate victims of the Great Reduction in Force of '95, were John Timberlake and Janet Felt. John's superb engineering skills were crucial to the completion of the Alpha Collector, and Janet's meticulous programming skills were instrumental in the modeling of the results.
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