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41.
OBJECTIVE: Family resources and coping skills are important to adaptation to pediatric chronic illness. Psychological and educational interventions have been found to enhance the coping skills of children with juvenile rheumatic disease (JRD) and their families. We examined the efficacy of a 3-day family retreat as a multidisciplinary, comprehensive treatment. METHODS: Children with JRD and their caregivers completed questionnaires assessing the children's behavioral and emotional functioning, pain, strain on caregivers' work and leisure activities, and caregivers' psychological distress before and 6 months after the family retreat. Principal caregivers were both parents for 16 children, mothers only for 10 children, and an aunt for 1 child. RESULTS: Improvements were found in children's emotional functioning, strain on caregivers' work, and strain on caregivers' leisure activities. Reductions in reported pain were not consistently revealed. CONCLUSIONS: Family retreats are an efficacious, multidisciplinary approach to helping families of children with JRD cope with the disease and its manifestations. Importantly, retreats offer a comprehensive intervention package that might not be available to families on an individual basis. 相似文献
42.
Group collaborative editing is an activity by which people geographically dispersed can edit the same document simultaneously. It makes use of computers and network communication to provide an interactive and convenient environment, so people can save much of their time and cost. We have developed a group collaborative editing system which not only allows participants to jointly view and process multimedia documents but also provides real-time interactive conversation facilities to let users feel realistic and friendly. This paper describes the concepts of group collaboration and the mechanisms of our system. It also presents the interface design strategy and the synchronization control method. 相似文献
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44.
Infections were a major cause of death in 84% of 38 autopsied renal allograft recipients in a south Indian hospital. Pyogenic bacteria and fungi were the most common etiological agents encountered, being present in 50 and 47% of cases, respectively. Tuberculosis and hepatitis B virus infection were more prevalent and Pneumocystis carinii and cytomegalovirus disease rarer than in comparable series from non-tropical countries. 1 case each of amoebiasis, strongyloidiasis and filariasis were the parasitic infections encountered. 相似文献
45.
The operation of zero-voltage-switching multi-resonant power converters (ZVSMRCs) limits the use of peak current-mode control. The charge control technique is found applicable to ZVSMRCs for improving dynamic performance. Charge control compares the total charge of the switch current to the control voltage to modulate the switching frequency. Since the charge of the switch current of the forward ZVSMRCs is proportional to the input voltage, charge control provides a fast inner loop and offers excellent transient response. Charge control also provides the possibility to achieve current sharing for ZVSMRC parallel applications 相似文献
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47.
The study of feedback fractional-order systems has been receiving considerable attention due to the facts that many physical systems are well characterized by fractional-order models, and that fractional-order controllers are used in feedback systems with the intention of breaking through the performance limitation of integer-order controllers. Owing to the lack of effective analytic methods for the time-domain analysis and simulation of linear feedback fractional-order systems, we suggest in this paper two reliable and accurate numerical methods for inverting fractional-order Laplace transforms. One is based on computing Bromwich's integral with a numerical integration scheme capable of accuracy control, and the other is based on expanding the time response function in a B-spline series. In order to demonstrate the superiority in solution accuracy and computational complexity of these two numerical methods over the Grunwald-Letniknov approximation method and Podlubny's analytic formulas, which are in a form of double infinite series, the time-domain simulations of the feedback control of a fractional-order process with a PDμ-controller and a fractional-order band-limited lead compensator are worked out. The simulation results indicate that a convergence problem indeed occurs in using Podlubny's infinite series expressions, and that the problem could not be overcome by a series acceleration scheme 相似文献
48.
The increased need for accurate and repeatable impurity profiling of shallow junction devices places stringent requirements on the profiling procedures and subsequent data reduction. A computer algorithm is described which simplifies the conversion of sheet resistance to impurity profile as required by the anodization and stripping technique. Error magnification commonly found in discrete data differentiation is avoided. Empirical mobility vs carrier concentration expressions are derived from several sources, and a self-contained computer algorithm is given which allows for data reduction on commonly available minicomputers using Fortran. The experimenter is provided with a check on the accuracy of the profile information. 相似文献
49.
Mammalian somatic cell cloning requires factors specific to the oocyte for reprogramming to succeed. This does not exclude that reprogramming continues during the zygote and cleavage stages. The capacity or role of zygotic and cleavage stages to reprogram somatic cell nuclei is difficult to assess due to the limited development of somatic cell nuclei transplanted into cytoplasts of these stages. Alternatively, tetraploid embryos have been used to study reprogramming and can be assessed for their contribution to extra-embryonic lineages. When mouse cumulus cell nuclei transgenic for Oct4-green fluorescent protein (GFP) were injected into intact two- and four-cell stage blastomeres, manipulated embryos developed into blastocysts with expression of Oct4-GFP as observed in embryos produced by nuclear transfer into metaphase II oocytes. However, only the latter contributed to extra-embryonic tissues in day 10.5 conceptuses, with the exclusion of the somatic genome in cells originating from transfer into blastomeres already at 5.5 days post conception. Somatic nuclei transferred into cleavage stage blastomeres reinitiated expression of an embyronic-specific transgene, but lacked the extent of reprogramming required for contribution to postimplantation development, even when complemented by an embryonic genome. 相似文献
50.
Joseph Leu 《软件工程师》2005,(9):55-56
TheongoingabilityofS iliconV alleyto generate in novations, grow th, goodjobsand risingincom e hasledm uch ofthew orldtoseektodefineandreplicateitskeyelem ents.S ilicon V alley is not just aone-tim e-onlyphe nom enon.A llthelessonsderivedfrom its experiencem aybeappliedatothertim es,inotherplacesto som e extend. T he fact that m ayors,governors,andotherofficialsfrom alloverthew orldflocktoS antaC laraC ounty,then return hom e to nick nam e theiraspiringhigh-technologyarea"S iliconV il-lage"… 相似文献