1. |
- Szymanski, J. J., et al.
(author)
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MEGA : A search for the decay mu –> e gamma
- 1994
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In: Intersections between particle and nuclear physics. Proceedings, 5th Conference, St. Petersburg, USA, May 31-June 6, 1994. ; , s. 789-792
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Conference paper (peer-reviewed)
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2. |
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3. |
- Chen, W., et al.
(author)
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Structure determination of Pt3Ti(111) by automated tensor LEED
- 1993
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In: Journal of Physics. - : IOP Publishing. - 0953-8984 .- 1361-648X. ; 5, s. 4585-4594
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Journal article (peer-reviewed)abstract
- An analysis of low-energy electron diffraction (LEED) I-V spectra from the clean Pt3Ti(111) surface was performed by comparing measured intensities with data calculated using an automated tensor LEED program, which employs a directed search optimization procedure. It was found that the topmost layer is pure Pt and that the other layers have the bulk composition. The first and second interlayer spacings are 2.23+or-0.03 AA and 2.21+or-0.03 AA respectively, corresponding to a contraction of 0.9% and 1.8% of the bulk value. The perpendicular buckling is 0.04 AA +or-0.05 AA in the top layer and 0.15 AA +or-0.04 AA in the second layer. The results are in full accordance with previous investigations of the physical and chemical properties of this surface.
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4. |
- Barros, H, et al.
(author)
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Arachidonic acid absorption in human jejunum in organ culture : effects of ethanol
- 1990
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In: European Journal of Clinical Investigation. - : Wiley. - 0014-2972. ; 20:5, s. 10-506
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Journal article (peer-reviewed)abstract
- Human jejunal tissue obtained by peroral biopsy was cultured in control medium and in medium containing 100 mmol l-1 ethanol. Subsequently, the incorporation and metabolism of [3H]-arachidonic and [14C]-linoleic acid were evaluated. Of the two fatty acids a significantly higher amount of [3H]-arachidonic acid was incorporated into phospholipids and more [14C]-linoleic acid was incorporated into triacylglycerols. This preferential distribution of the labelled fatty acids was not affected by ethanol, but when ethanol was present in the tissue culture medium, there was a significant decrease in the incorporation of both fatty acids into tissue phospholipids. The study thus shows that ethanol in moderate concentrations can affect human jejunal absorption and metabolism of polyenoic fatty acids, contributing to a decrease in the amount of eicosanoid precursors available in jejunal tissue.
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5. |
- Chen, F., et al.
(author)
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Evaluation of a workstation for letter sorting in the Beijing post office
- 1993
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In: Occupational and environmental economics. - : Indian Society of Ergonomics.. - 819005080X ; , s. 61-66
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Conference paper (peer-reviewed)abstract
- In the Chinese postal system, letters are sorted manually using a sorting frame, consisting of vertical and horizontal arrays of pigeon-holes of different dimensions. Letter sorting is a time consuming and a mentally intensive task involving repetitive movements of shoulder and hand muscles. Musculoskeletal complaints and disorders of the lower back, shoulder and hand occur frequently among the letter sorting workers. A total of 293 letter-sorters (71 males and 222 females) from Beijing Postal Sorting Office were subjected to a general health check-up including musculoskeletal disorders coupled with administration of a questionnaire. The worker's daily work load was evaluated by counting the number of letters sorted in each pigeon-hole in the sorting frame and also by considering their arm movements and body postures. The workplace dimensions were also measured. Results revealed that 62.1% of the workers complained of low back pain, 78.5% of shoulder pain and 48.8% of hand pain. A high percentage of workers seemed to have mental intensive symptoms, such as, headache, dizziness and drowsiness. Almost 25% of the female wokers indicated irregularity in their menstruation. An improved ergonomic design of the sorting frame is recommended.
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6. |
- Chen, Q, et al.
(author)
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Desaturation and chain elongation of n - 3 and n - 6 polyunsaturated fatty acids in the human CaCo-2 cell line
- 1993
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In: Biochimica et Biophysica Acta. - : Elsevier BV. - 0006-3002. ; 1166:2-3, s. 193-201
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Journal article (peer-reviewed)abstract
- Human CaCo-2 cells were incubated with [14C]linoleic (18:2(n - 6)), [14C]linolenic (18:3(n - 3)) and [3H]eicosapentaenoic acid (20:5(n - 3)), and the interconversion of the radioactive fatty acids to higher homologues and their acylation into triacylglycerols (TG) and phospholipids were examined. An active conversion of [14C]18:3 to [14C]20:5 and [14C]docosapentaenoic acid (22:5(n - 3)) and of [3H]20:5 to [3H]22:5, but not to [3H]docosahexaenoic acid (22:6(n - 3)) was observed. In relation to the amounts that had been incorporated into cellular phospholipids and TG, the interconversion of [14C]18:3 clearly exceeded that of [14C]18:2. Addition of 10-100 microM 18:2 or 10-50 microM arachidonic acid (20:4(n - 6)) increased the percent interconversion of [14C]18:2 to [14C]20:4. E.g., addition of 50 microM 20:4 increased the formation of [14C]20:4 from 4.4 +/- 0.1% to 5.9 +/- 0.8%, decreased the incorporation into phospholipids from 64.8 +/- 6.3% to 31.4 +/- 1.2% and increased the incorporation into TG from 8.8 +/- 0.4% to 28.8 +/- 1.1%. In contrast, addition of 10-100 microM 18:3 or 20:5 significantly decreased the interconversion of both [14C]18:2 and [14C]18:3. E.g., addition of 50 microM 20:5 decreased the formation of [14C]20:4 from [14C]18:2 from 4.4 +/- 0.1% to 0.9 +/- 0.1%, whereas the effects on the acylation reactions were very similar to those of 20:4. 20:5 also decreased the formation of interconversion products from [14C]18:3. 18:2 and 20:4 caused a smaller decrease in the formation of [14C]20:5 and actually increased percent conversion to [14C]22:5. The percent conversion of [3H]20:5 to [3H]22:5 was also increased by the addition of 50-100 microM unlabeled 20:5. [14C]18:2 and [14C]18:3 were predominantly incorporated into phosphatidylcholine (PC) whereas more of the radioactive 20:4, 20:5 and 22:5 was incorporated into phosphatidylethanolamine (PE). An active fatty acid interconversion catalyzed by delta 6 and delta 5 desaturases thus occurs in the human CaCo-2 cell line, whereas conversion of 20:5(n - 3) to 22:6(n - 3) could not be demonstrated. The desaturation-elongation pathway has a preference for 18:3(n - 3) and is subjected to an efficient feedback regulation by 20:5(n - 3). Formation of 22:5 increases with available 20:5 mass and by the presence of other polyunsaturated fatty acids competing with 20:5 for acylation into phospholipids.
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