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11.
This paper argues that shiftworkers may have gradually habituated to their problems and hence that they underestimate them. Some support for this view was obtained in a 'reminiscence' questionnaire study of retired UK Police Officers who had all subsequently taken on another (mainly day-time) job. They completed a specially constructed questionnaire, which included several measures of health and well being, and in which they were asked to reminisce about how they had felt while still a shiftworker. These reminiscence scores were compared to their current perception of how they were. The results clearly indicated that individuals in retrospect perceive their situation as being worse than they realised at the time. This effect was most marked for scores on the General Health Questionnaire and Chronic Fatigue scale. The results of this study draw attention to a potential confounding in much of the shiftwork literature which demands further, more detailed, investigation. 相似文献
12.
Expression of a human homeobox-containing gene is regulated by 1,25(OH)2D3 in bone cells 总被引:1,自引:0,他引:1
JE Hodgkinson CL Davidson J Beresford PT Sharpe 《Canadian Metallurgical Quarterly》1993,1174(1):11-16
The seasonal variation in the nutrient composition of Enhydra fluctuans and Marsilea quadrifolia, two edible semi-aquatic plants, was studied in order to promote their consumption as green leafy vegetables. Both plants had a high crude protein content throughout all harvesting seasons. Enhydra fluctuans had a low ash content and was a good source of beta-carotene (3.7 to 4.2 mg/100 g on a fresh weight basis). Marsilea quadrifolia exhibited wide fluctuations between seasons and was not very promising in nutrient composition when compared to other commonly used green leafy vegetables. 相似文献
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A quantum-well-intermixing process for wavelength-agile photonic integrated circuits 总被引:1,自引:0,他引:1
Skogen E.J. Barton J.S. Denbaars S.P. Coldren L.A. 《IEEE journal of selected topics in quantum electronics》2002,8(4):863-869
Wavelength-agile photonic integrated circuits are fabricated using a one-step ion implantation quantum-well intermixing process. In this paper, we discuss, the issues in processing optimized widely tunable multisection lasers using this technique and present the results achieved using this process. This quantum-well intermixing process is general in its application and can be used to monolithically integrate a wide variety of optoelectronic components with widely tunable lasers. 相似文献
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Totterdell Peter; Spelten Evelien; Smith Lawrence; Barton Jane; Folkard Simon 《Canadian Metallurgical Quarterly》1995,80(1):43
Although regulations on work hours usually include a minimum weekly rest period, there is little empirical evidence concerning recovery from work. Shift-working nurses (N?=?61) used a handheld computer for 28 days to complete self-ratings, cognitive-performance tasks, and a sleep diary. Many measures were worse on rest days that followed a night shift rather than a day shift and tended to be worse on 1st rest days compared with subsequent rest days. Alertness was lowest on the 1st rest day following a night shift. Social satisfaction was better on workdays that were preceded by 2 rather than 1 rest day. Reaction time (RT) decreased over consecutive night shifts and tended to increase over rest days following night shifts. The results are interpreted as being consistent with the combined adaptive costs of fatigue and adjustment to and from a nocturnal routine. The practical implications for scheduling rest days are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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A measurement technique is presented which uses narrow, fast-rise-time pulses applied to both the gate and the drain of a GaAs MESFET to obtain the drain characteristics of the device. This allows the characteristics of the device to be obtained which correspond to frequencies above those at which surface and substrate traps can respond. The resulting characteristics show significant departures from those obtained using conventional long pulse and DC measurement techniques. 相似文献
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RG Jaeger PT de Oliveira MM Jaeger VC de Araújo 《Canadian Metallurgical Quarterly》1997,84(6):663-667
BACKGROUND: Endoscopic sclerotherapy (ST), widely used as treatment of bleeding esophageal varices, might cause motility disturbances of the esophagus as well as mucosal damage. We performed this study to evaluate the long-term effects of repeated sclerotherapy on esophageal motility and mucosa. METHODS: Ten patients with liver cirrhosis and bleeding esophageal varices treated with repeated ST were evaluated after the last ST, median 52 months, by esophageal manometry and gastroscopy where forceps biopsies were taken. RESULTS: We found a significant difference in the distal esophageal sphincter intraabdominal length. The distal esophageal sphincter pressure was somewhat lower in the ST group although the difference did not reach statistical significance. There was infiltration of neutrophil leukocytes in biopsies from four patients and normal findings in the rest. CONCLUSIONS: Long-term follow-up evaluation showed statistically longer distal esophageal intraabdominal length in the ST group. No mucosal alterations were found at the histopathological investigation. 相似文献