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1.
Silverberg Koerner Susan; Wallace Sara; Jacobs Lehman Stephanie; Lee Sun-A; Escalante Kristine A. 《Canadian Metallurgical Quarterly》2004,18(1):46
This study addressed two main questions: (a) Are adolescent sons and daughters exposed to sensitive maternal disclosures after divorce with similar frequency and in similar detail? and (b) Does gender act as a moderator in the association between maternal disclosures and adolescent adjustment difficulties? Forced-choice and open-ended data were collected from 194 adolescents within 2 years after their parents' divorce. Quantitative analyses revealed that although the majority of adolescents experience some level of maternal disclosure, neither frequency nor detail of maternal disclosure differed as a function of adolescent gender. Frequent and detailed maternal disclosures were associated with adolescent adjustment difficulties, primarily psychological distress. Gender did not moderate that significant association. Qualitative analysis shed light on the link between maternal disclosures and adolescent distress, suggested the importance of how disclosures are made, and revealed several gender differences in reactions to maternal disclosures. Implications of the findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
Removal of gold from basic solutions containing [Au(CN)2]? has been demonstrated using the inherently conducting polymer polypyrrole. Polymers containing sulfonated aromatic dopants have been found to display a significant ability to remove gold from such solutions. Experiments performed in solutions containing both gold and copper cyanide complexes indicate that the recovery process is not highly selective. However, the polypyrroles used display significantly faster rates of gold recovery than activated carbon. © 2003 Society of Chemical Industry 相似文献
3.
Understanding the differences between how novice and experienced designers approach design tasks 总被引:2,自引:1,他引:1
Research was undertaken to understand how to provide the most appropriate support for novice designers in engineering design.
However, how designers apply their experience and knowledge is not understood and further research in this area is required.
This paper describes an observational study to understand how novice and experienced designers approach design tasks.
Electronic Publication 相似文献
4.
Wallace A.M. Sung R.C.W. Buller G.S. Harkins R.D. Warburton R.E. Lamb R.A. 《Vision, Image and Signal Processing, IEE Proceedings -》2006,153(2):160-172
A new multi-spectral laser radar (ladar) system based on the time-correlated single photon counting, time-of-flight technique has been designed to detect and characterise distributed targets at ranges of several kilometres. The system uses six separated laser channels in the visible and near infrared part of the electromagnetic spectrum. The authors present a method to detect the numbers, positions, heights and shape parameters of returns from this system, used for range profiling and target classification. The algorithm has two principal stages: non-parametric bump hunting based on an analysis of the smoothed derivatives of the photon count histogram in scale space, and maximum likelihood estimation using Poisson statistics. The approach is demonstrated on simulated and real data from a multi-spectral ladar system, showing that the return parameters can be estimated to a high degree of accuracy. 相似文献
5.
IC Wilson TJ Gardner JM DiNatale AM Gillinov WE Curtis DE Cameron 《Canadian Metallurgical Quarterly》1993,106(5):805-810
Leukocyte depletion improves early postischemic ventricular performance in neonatal models of global myocardial ischemia. However, the rate of leukocyte reaccumulation after cardiopulmonary bypass and its subsequent impact on myocardial function is not known. This laboratory study examined the effect of leukocyte depletion on myocardial performance during the initial 6-hour period after bypass in an in situ, in vivo porcine model of neonatal cardiac surgery. Fifteen 3- to 5-day-old piglets (eight control and seven leukocyte depleted animals) were instrumented by placement of left ventricular short-axis sonomicrometry crystals and an intraventricular micromanometer catheter. Mechanical leukocyte depletion was achieved with Pall RC100 filters (Pall Biomedical, Inc., Fajardo, Puerto Rico) in the cardiopulmonary bypass circuit. Neonatal hearts were subjected to 90 minutes of hypothermic ischemia after a single dose of cold crystalloid cardioplegia. Two control animals died after the operation and were excluded from data analysis. Leukocyte filtration reduced the granulocyte count during initial myocardial reperfusion to 0.8% of control values. However, circulating granulocyte counts increased in leukocyte depleted animals throughout the postoperative period, reaching 68% of control values by 6 hours. Despite this rapid return of circulating granulocytes, animals subjected to leukocyte depletion had significantly better preservation of left ventricular performance (measured by preload recruitable stroke work, p < or = 0.02), left ventricular systolic function (measured by end-systolic pressure-volume relationship, p < or = 0.05), and ventricular compliance (p < or = 0.04) during the experiment. These changes in ventricular function were associated with a significant increase in left ventricular water content (p < or = 0.02) and tissue myeloperoxidase activity (p < or = 0.005) in control animals compared with leukocyte depleted animals. This study demonstrates that leukocyte depletion during initial reperfusion results in sustained improvement in postischemic left ventricular function despite the rapid return of granulocytes to the circulation. 相似文献
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Assuming that the chemical reactions used to synthesize a combinatorial library member are successful, then knowledge of the specific reaction sequence is equivalent to knowing the member's chemical identity. Because the determination of chemical identity is typically not automatable and requires a substantial amount of material, schemes that encode a member's reaction history onto the reaction platform are of value. The primary benefits of encoding are relational nomenclature (all methods) and automated handling (some methods). Encoding methods evaluated to date are spatial, graphical, chemical, spectrometric, electronic, and physical. 相似文献
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Although accepted surgical techniques for peripheral nerve repair remain largely unchanged over the past three decades, much progress has been made toward understanding the mechanisms involved in nerve regeneration, and consequently toward providing adjunctive measures to enhance this regenerative process. We present a comprehensive review of the significant advances made in several aspects of nerve repair over the past decade, and particularly the past few years, and provide a few examples of facial nerve repair using the standard neurorrhaphy techniques recommended today. Several conclusions were drawn after thorough review of the literature. Early repair of injured nerves is preferred, and there appears to be no benefit to waiting for 3 weeks. Severed nerves should be repaired with monofilament 9-0 nylon suture placed in epineurial fashion. Fibrin glue confers no benefit in reattaching injured nerves. Likewise, theoretical advantages of laser neurorrhaphy have not resulted in improved nerve regeneration. Finally, trophic factors, such as apolipoproteins and nerve growth factor, and tubulization both appear to offer promise for future experimental and clinical progress in nerve repair. However, further work must be done to prove their efficacy. 相似文献