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361.
Stefan Franz Nemec Ursula Nemec Peter C. Brugger Dieter Bettelheim Siegfried Rotmensch John M. Graham Jr. David L. Rimoin Daniela Prayer 《黑龙江环境通报》2012,32(3):205-213
Magnetic resonance imaging (MRI) appears to be increasingly used, in addition to standard ultrasonography for the diagnosis of abnormalities in utero. Previous studies have recently drawn attention to the technical refinement of MRI to visualize the fetal bones and muscles. Beyond commonly used T2-weighted MRI, echoplanar, thick-slab T2-weighted and dynamic sequences, and three-dimensional MRI techniques, are about to provide new imaging insights into the normal and the pathological musculoskeletal system of the fetus. This review emphasizes the potential significance of MRI in the visualization of the fetal musculoskeletal system. © 2012 John Wiley & Sons, Ltd. 相似文献
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John Carrell Derrick Tate Shiren Wang Hong-Chao Zhang 《Journal of Cleaner Production》2011,19(17-18):2066-2074
This paper explores a means to simplify disassembly by engineering a snap-fit that automatically releases upon exposure to a heat field thus limiting manual labor or machine operation for disassembly. Shape memory polymer (SMP) snap-fits were designed and manufactured to actively release upon a thermal trigger. Snap-fits were designed with an added feature known here as a release angle that would allow for an uninterrupted movement for disassembly in the presence of an elevated temperature. SMP snap-fits were then manufactured and tested. Testing was performed for demonstration of the active release of the SMP snap-fits and for analysis of active disassembly (AD) process parameters. Taguchi methods were used to analyze the AD process parameters, including heating method and disassembly temperature. The results from this research show the successful demonstration of the SMP snap-fits within a manufactured product housing. AD process parameter analysis shows that both the heating method and temperature affect the AD process. The analysis determines that by increasing the heat exchange rate the snap-fit disassembly time is shortened. From the performed experiments, it was seen that an Oil bath at 150 °C produced the best results in regards to disassembly time and signal-noise ratio. The results from experimentation demonstrate the possibility of acceptable heat-releasable fasteners for more efficient disassembly and exhibit benefits over current AD elements comprised of shape memory alloys. 相似文献
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Hari Eswaran Diana Escalona-Vargas Elijah H. Bolin James D. Wilson Curtis L. Lowery 《黑龙江环境通报》2017,37(2):193-196
Fetal magnetocardiography provides the requisite precision for diagnostic measurement of electrophysiological events in the fetal heart. Despite its significant benefits, this technique with current cryogenic based sensors has been limited to few centers, due to high cost of maintenance. In this study, we show that a less expensive non-cryogenic alternative, optically pumped magnetometers, can provide similar electrophysiological and quantitative characteristics when subjected to direct comparison with the current technology. Further research can potentially increase its clinical use for fetal magnetocardiography. © 2016 John Wiley & Sons, Ltd. 相似文献
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Osmoregulation by the European glass prawn Palaemon elegans Rathke, 1837 was impaired at low temperature (2°C) and high salinities (full strength sea water 35 PSU). Under these conditions,
small individuals showed stronger osmoregulatory ability than larger individuals. This observation could partially explain
differences in winter migrations off the UK coast where mainly large P. elegans go offshore, leaving smaller individuals in high shore rock pools, a finding consistent with winter experiments in situ. 相似文献