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1.
J. Jiang M. D. Olson 《International journal for numerical methods in engineering》1993,36(13):2219-2243
Numerical investigations are carried out to verify the new super element model developed in Reference 1 for non-linear analysis of stiffened box structures. The results presented here are obtained from a variety of examples which are chosen to illustrate the accuracy and convergence of the model in various applications. Good agreement is obtained for most of the problems considered and the present formulation is found to be accurate and economical for preliminary engineering design. 相似文献
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A Voskova-Goldman A Peier CT Caskey CS Richards LG Shaffer 《Canadian Metallurgical Quarterly》1997,48(6):1633-1638
The challenge of Duchenne muscular dystrophy (DMD) carrier identification resides in the ability to identify the presence of a mutant gene over the background contributed by the normal allele. Current diagnosis of carrier status when a deletion has been identified in a proband is based on an analysis of a gene dosage. We present a diagnostic strategy that uses fluorescence in situ hybridization (FISH) to detect female carriers with major deletions in the dystrophin gene. We screened a human X-chromosome-derived genomic library with a full-length dystrophin cDNA and isolated 15 dystrophin-specific cosmids that contain DMD gene exons. Six cosmids were further tested as FISH probes in control individuals and subsequently applied on chromosomes from eight males with DMD and known deletions and on samples from three female carriers. As expected, X chromosomes in normal females displayed four signals, two for the DMD-specific probe and two for the X-chromosome centromeric probe. Hybridization on chromosomal spreads from carriers of deletions revealed only one signal from the DMD-specific probe and two from the control centromeric probe. Males carrying deletions showed no DMD-specific signal for the deleted exons tested. Our data indicate that FISH could represent an alternative method for the detection of female carriers with DMD gene deletions. 相似文献
4.
CH Alleyne TH Fox JJ Olson GA Cotsonis I Crocker RA Bakay 《Canadian Metallurgical Quarterly》1997,5(1):20-30
The objective of this survey was to demonstrate whether a primary care track internal medicine residency program emphasizing community-based health care of the urban sick poor trains physicians who will continue to practice in general internal medicine or similar fields. Thirty-five primary care residents (100% of graduates) who trained from 1976 through 1993 in the Adult Primary Care Track of the Internal Medicine Residency Program at St. Vincent's Hospital, New York were used as participants. 相似文献
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LG Westergaard PE Rasmussen S Maigaard HJ Ingerslev AN Andersen JF Larsen J Starup PJ Hornnes CY Andersen 《Canadian Metallurgical Quarterly》1993,155(33):2511-2514
Medical indications for in vitro fertilization and embryo transfer (IVF-ET) internationally and in Denmark are reviewed. Reports from large international centres document that tubal infertility, unexplained infertility, endometriosis and male infertility are equally good indications for IVF. Traditionally, tubal infertility has been the only medical indication qualifying for IVF treatment within the National Health Service in Denmark. Thus, in this country, couples with unexplained and male infertility and with endometriosis have to pay up to 25,000 D.Kr. per IVF-ET treatment in private fertility clinics. Since there is no scientific basis for this discrimination, it is urged that the present rules are changed, so that couples with unexplained and male infertility and endometriosis are also allowed IVF treatment free of charge in the public fertility clinics. 相似文献
6.
Studied the differences in moral orientation in terms of gender specific modes of reasoning, in 2 experiments. In Exp 1, 32 Ss (aged 24–55 yrs) were read the "Heinz dilemma," and asked 3 questions regarding it. Deliberative and justificatory strategies were identified on the basis of the presence or absence of the higher level knowledge structures. In Exp 2, 40 undergraduates were presented with "Michael and Kohlberg Heinz dilemma," followed by a set of relevant questions. Male Ss preferred to apply a norm or rule in their solutions, while females rejected the application of a norm and sought alternative solutions. This was replicated in Exp 2, but the pattern was reversed with female Ss preferring to apply a norm. Males were divided in their use of either strategy indicating that although, genders differed in their judgments as to which norms or rules to apply; once adopted, norms and rules were used in similar ways. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
Timothy G. Trucano Dennis E. Grady Glenn D. Kubiak Marlin E. Kipp Richard E. Olson Archie Farnsworth 《International Journal of Impact Engineering》1995,17(4-6):873-890
xtreme
ltra
iolet
ithography (EUVL) seeks to apply radiation in a wavelength region centered near 13 nm to produce microcircuits having feature sizes 0.1 micron or less. A critical requirement for the commercial application of this technology is the development of an economical, compact source of this radiation which is suitable for lithographic applications. A good candidate is a laser-plasma source, which is generated by the interaction of an intermediate intensity laser pulse (up to 1012 W/cm2) with a metallic target. While such a source has radiative characteristics which satisfy the needs of an EUVL source, the debris generated during the laser-target interaction strikes at the economy of the source. Here, we review the use of concepts and computer modeling, originally developed for hypervelocity impact analysis, to study this problem. 相似文献
8.
We propose a new, less costly, design to test the equivalence of digital versus analogue mammography in terms of sensitivity and specificity. Because breast cancer is a rare event among asymptomatic women, the sample size for testing equivalence of sensitivity is larger than that for testing equivalence of specificity. Hence calculations of sample size are based on sensitivity. With the proposed design it is possible to achieve the same power as a completely paired design by increasing the number of less costly analogue mammograms and not giving the more expensive digital mammograms to some randomly selected subjects who are negative on the analogue mammogram. The key idea is that subjects who are negative on the analogue mammogram are unlikely to have cancer and hence contribute less information for estimating sensitivity than subjects who are positive on the analogue mammogram. To ascertain disease state among subjects not biopsied, we propose another analogue mammogram at a later time determined by a natural history model. The design differs from a double sampling design because it compares two imperfect tests instead of combining information from a perfect and imperfect test. 相似文献
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