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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.
Dean Gillette 《Information Systems Management》1991,8(2):76-79
As most IS managers know, time is often wasted during most business meetings. As technological advances in the various types of teleconferencing systems continue, teleconferencing will serve as the preferred method of conducting meetings because of the resulting time and cost savings. 相似文献
6.
Dean Gillette 《Information Systems Management》1991,8(4):65-67
Designing a geographically extensive corporate network at the lowest cost means dealing with the vagaries of handling multiple carriers and widely varying levels of service. Further complicating matters are tariff structures that often dictate optimum corporate network infrastructures. This column reviews some of the available and emerging services and the best network structure options. 相似文献
7.
Two lignite samples, Beulah No. 3 and Big Brown No. 1, were liquefied at 420 °C using H2 and synthesis gas to determine the optimum beneficial amount of H2S in the batch autoclave reactor. Under the conditions employed, 50–100 psi partial pressure of H2S, nominally 4–10 wt% of daf lignite, was optimum for both samples. Synthesis gas outperformed H2 with and without H2S for the liquefaction of the two coals. 相似文献
8.
Geoffrey Rowden Shirley Dean James Campbell Philip Belitsky 《Microscopy research and technique》1985,2(6):547-555
Aspiration biopsy of tumors and transplanted organs is a popular atraumatic method for diagnosis and also for the management of patients. Apart from the cytological analyses, it is clear that large aggregates of cells are obtained and these may be examined by electron microscopy. A study was carried out with dogs to assess the yield of intact glomeruli and tubules, resulting from a standard fine-needle aspiration procedure. Employing a 20-gauge needle, yields of approximately ten intact glomeruli were obtained with a tissue processing protocol that utilized filtration through a nylon mesh and backwashing, to resuspend the trapped aggregates. Processing for electron microscopy was carried out in microcentrifuge tubes. The ultrastructural preservation was excellent and the extension of these studies to investigations of not only renal transplantation, but also for diagnosis in human renal diseases of a broad spectrum, is suggested. 相似文献
9.
Somatotrophs become a significant population by day 16 of chicken embryonic development. We have previously demonstrated that an earlier induction of GH cell differentiation is possible with the addition of day 16 embryonic serum to cultures of day 12 pituitary cells, an age when somatotrophs are rare. The present study was designed to identify the blood-borne signal(s) responsible for the serum activity, using reverse hemolytic plaque assays to identify individual GH-secreting cells. The activity was found to be a heat-stable, ether-soluble compound(s) that is bound or inhibited by a trypsin-sensitive protein. The extent of GH cell differentiation was greater (P < 0.05; n = 3) in response to the ether phases of heated day 16 (14.1 +/- 0.4% of all cells) and day 12 sera (9.3 +/- 0.4%) than with untreated serum from days 16 and 12 (6.1 +/- 0.4% and 0.82 +/- 0.4%, respectively). Furthermore, ether-extracted day 16 serum was more effective than ether-extracted day 12 serum, which was also different from basal (0.85 +/- 0.4%; P < 0.05). Based on this biochemical profile, the abilities of various steroids to stimulate differentiation were tested. Three steroids were found to stimulate somatotroph differentiation in vitro: 17beta-estradiol, corticosterone, and progesterone. However, the estradiol receptor antagonist, tamoxifen, while abolishing the effect of estradiol, had no effect on the induction of differentiation by day 16 serum. In contrast, RU486, a specific glucocorticoid receptor antagonist in chickens, blocked the stimulatory effects of corticosterone, progesterone, and day 16 serum on somatotroph differentiation. We next tested whether the active compound in day 16 embryonic serum was corticosterone, the predominant glucocorticoid in chickens. Incubation of day 16 serum with corticosterone antiserum, but not control antiserum, suppressed day 16 serum-induced GH cell differentiation. Therefore, we conclude that corticosterone is the blood-borne signal capable of stimulating somatotroph differentiation in vitro. The present findings together with previous reports indicate that somatotroph differentiation during embryonic development may result from an increase in circulating glucocorticoid concentrations. 相似文献
10.
P. A. Hausladen D. C. Weisser N. R. Lobanov L. K. Fifield H. J. Wallace 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2002,190(1-4):402-404
We report on improvements in the overall intensity of a sputter ion source that evolved originally from an NEC MCSNICS. Beam output increases benefit both AMS measurements and nuclear physics experiments using low natural abundance beams. In particular, minor changes in source geometry suggested by a combination of electrostatic calculations and simple design principles have yielded increases in extracted negative ion intensity of nearly a factor of 4. 相似文献