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891.
Fuchs Lynn S.; Fuchs Douglas; Compton Donald L.; Powell Sarah R.; Seethaler Pamela M.; Capizzi Andrea M.; Schatschneider Christopher; Fletcher Jack M. 《Canadian Metallurgical Quarterly》2006,98(1):29
The purpose of this study was to examine the cognitive correlates of 3rd-grade skill in arithmetic, algorithmic computation, and arithmetic word problems. Third graders (N = 312) were measured on language, nonverbal problem solving, concept formation, processing speed, long-term memory, working memory, phonological decoding, and sight word efficiency as well as on arithmetic, algorithmic computation, and arithmetic word problems. Teacher ratings of inattentive behavior also were collected. Path analysis indicated that arithmetic was linked to algorithmic computation and to arithmetic word problems and that inattentive behavior independently predicted all 3 aspects of mathematics performance. Other independent predictors of arithmetic were phonological decoding and processing speed. Other independent predictors of arithmetic word problems were nonverbal problem solving, concept formation, sight word efficiency, and language. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
892.
Zelman Diane C.; Brandon Thomas H.; Jorenby Douglas E.; Baker Timothy B. 《Canadian Metallurgical Quarterly》1992,60(6):943
126 smokers were randomly assigned to 6-session smoking cessation treatments consisting of 1 of 2 counseling strategies (skills training or support) and 1 of 2 nicotine exposure strategies (nicotine gum or rapid smoking). Counseling and nicotine strategies were completely crossed: All 4 combinations resulted in equivalent 1-yr abstinence rates. Skills training produced higher initial cessation and more coping responses posttreatment than did support. Rapid smoking, but not nicotine gum, produced tachycardia to the taste of cigarettes posttreatment, consistent with cigarette aversion. The treatments were differentially effective among subpopulations of smokers: Ss high in pretreatment negative affect responded best to support counseling; those low in pretreatment negative affect responded best to skills training. Self-reports of pretreatment craving predicted response to the nicotine-exposure treatments. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
893.
Charmian J. O'Connor Douglas R. Cleverly 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1994,61(3):209-214
A Fourier-transform infrared (FT-IR) spectroscopic method has been developed for assaying the bile salt-stimulated human milk lipase (BSSL, EC3.1) catalyzed hydrolysis of triolein in AOT reversed micelles in iso-octane. At 37°C in 50 mmol dm?3 AOT the molar absorbtivities for the carbonyl stretching frequencies for triolein (at 1751 cm?1) and oleic acid (at 1714 cm?1) were 1646 dm3 mol?1 cm?1 and 743 dm?3 mol?1 cm?1, respectively. The rate was linearly dependent upon the concentration of enzyme in the water pool up to 10 mg cm?3 and maximum activity was observed at a ratio (w0) of [H2O]:[AOT] = 16·7. Using these conditions, and in the presence of 10 mmol dm?3 sodium taurocholate (TC), the derived Michaelis–Menten parameters Vmax and Km were 57·5 μmol min?1 mg?1 and 5·53 mmol dm?3, respectively. These results are compared with those obtained in an oil-in-water microemulsion system and are discussed in terms of the relative partitioning of the enzyme and the substrate in the aqueous and oil phases and the interfacial concentration of the substrate in the two systems. 相似文献
894.
Insomnia is a debilitating and widespread complaint. Concern over the iatrogenic effects of pharmacological therapies has led to the development of several psychological treatments for insomnia. To clarify the effects of these treatments, 66 outcome studies representing 139 treatment groups were included in a meta-analysis. The results indicated that psychological treatments produce considerable enhancement of both sleep patterns and the subjective experience of sleep. In terms of enhancing sleep onset, active treatments were all superior to placebo therapies but did not differ greatly in efficacy. Greater therapeutic gains were available for participants who were clinically referred and who were not regular users of sedative hypnotics. Future research directions are suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
895.
Douglas W. Farwell Linda Kuramoto Denis Lee Eileen M. Trauth Christine Winslow 《Information Systems Management》1992,9(2):7-14
An Is paradigm shift will create problems of adjustment and new opportunities for IS professionals. To function effectively in this new world, current and future IS professionals must acquire new knowledge and skills. This will not be easy to accomplish and will require the joint effort of both industry and academia. However, the payoffs from such human investments will be enormous. The existence of a cadre of capable IS professionals who can intelligently and effectively apply emerging information technologies not only affects the success of individual organizations but improves the competitiveness of our nation. 相似文献
896.
Two adaptive control strategies using pattern-based performance feedback are studied. Both strategies are based on an analysis of patterns exhibited in the recent history of the controller error and focus on adaptation opportunities that arise as a result of sustained set-point changes. The strategies consider a two-parameter adaptation where model gain and time constant are updated after each pattern analysis. The first method uses a vector quantizing neural network for the pattern analysis task. The network is constructed using exemplar controller error patterns developed by deliberately mismatching parameters of a PI controller's internal model against those of an ‘ideal’ simulated system. Once on-line, the network then receives controller error response patterns from the actual application and outputs controller model parameter updates. The second method uses a rule-based pattern analysis to determine features of the controller error response pattern. These pattern features are evaluated relative to user-specified desired features, and rules and procedures again produce PI controller model parameter updates. Both methods are compared in setpoint tracking demonstrations to determine qualitative robustness for non-ideal situations such as measurement noise, constraint of the manipulated variable, model order mismatch and unmeasured oscillatory disturbances. Results reveal that rule-based feature analysis has the benefit of being time independent but the disadvantage of not being able to handle non-ideal situations without a cumbersome rule base. Although the neural network approach requires specification of a time window for pattern analysis, the method proves to be easier to implement and more robust when confronted with non-ideal operating situations. 相似文献
897.
An operating model of a microprocessor-based system for use in electrical substations is described. The control system performs substation control functions important in continuous process industries? automatic transfer and sequential reacceleration of motors following short duration voltage outputs. The system provides an interface for load shedding and motor control, and has several useful data-gathering features. The model has been rigorously tested using a simulator which mimics substation input/output signals in real time. Performance capabilities and security/reliability aspects of both hardware and software are discussed with reference to conventional hardwired schemes. 相似文献
898.
W Cao SS Tykodi MT Esser VL Braciale TJ Braciale 《Canadian Metallurgical Quarterly》1995,378(6554):295-298
T cells are normally activated when the peptide for which they are specific is presented to them in the context of the appropriate major histocompatibility complex (MHC) (class I and Class II for CD8+ and CD4+ T cells, respectively). An increasing body of evidence indicates that structural homologues of the immunogenic peptide can partially activate or antagonize CD4+ T cells. CD8+ T cells may also be partially antagonized by such peptides, and self-derived peptides of this type may play a role in CD8+ T cell selection in the thymus. Activated CD8+ T cells lyse their targets by perforin-dependent granule exocytosis and by inducing apoptosis mediated by CD95 (also known as Fas or APO1) with its ligand (CD95L). Here we show that a clone of Kd-restricted CD8+ T cells specific for influenza haemagglutinin, which can also be activated in a crossreactive manner by a peptide derived from a myeloma tumour immunoglobulin heavy-chain variable region (IgVH) to kill by both routes, kills only by the CD95-CD95L pathway when stimulated by the corresponding germline IgVH peptide. As this germline IgVH peptide differs from the tumour peptide only at a single position buried in the MHC-binding groove, this indicates that CD95-CD95L-mediated killing can be triggered independently of the perforin-mediated pathway, and can be selectively affected by changes in MHC conformation. 相似文献
899.
Paul A. Basore James M. Gee M.Elaine Buck W.Kent Schubert Douglas S. Ruby 《Solar Energy Materials & Solar Cells》1994,34(1-4)
We developed an emitter diffusion process that yields a near-ideal doping profile with a passivating oxide in a single furnace step. Because this process subjects the material to only one high-temperature thermal excursion, bulk lifetime is better preserved. This is especially true for lower-cost silicon materials containing a high concentration of oxygen or carbon. Using this process, we routinely obtain one-sun cell efficiencies over 19% on float-zone material and over 18% on Czochralski material. Using solar-grade Czochralski material, we have demonstrated record efficiencies of 18.3% at one sun and 20.0% under concentration. Simple processes that yield high-performance diffusion profiles are expected to become increasingly important as manufacturers adopt improved techniques for ohmic contacts. 相似文献
900.
R Faggioni S Gatti MT Demitri R Delgado B Echtenacher P Gnocchi H Heremans P Ghezzi 《Canadian Metallurgical Quarterly》1994,123(3):394-399
We studied the role of reactive oxygen intermediates (ROI) in lipopolysaccharide (LPS)-induced pulmonary edema. LPS treatment (600 micrograms/mouse, IP) was associated with a marked induction of the superoxide-generating enzyme xanthine oxidase (XO) in serum and lung. Pretreatment with the antioxidant N-acetylcysteine (NAC)--1 gm/kg orally, 45 minutes before LPS--or with the XO inhibitor allopurinol (AP)--50 mg/kg orally at -1 hour and +3 hours--was protective. On the other hand nonsteroidal antiinflammatory drugs (ibuprofen, indomethacin, and nordihydroguaiaretic acid) were ineffective. These data suggested that XO might be involved in the induction of pulmonary damage by LPS. However, treatment with the interferon inducer polyriboinosylic-polyribocytidylic acid, although inducing XO to the same extent as LPS, did not cause any pulmonary edema, indicating that XO is not sufficient for this toxicity of LPS. To define the possible role of cytokines, we studied the effect of direct administration of LPS (600 micrograms/mouse, IP), tumor necrosis factor (TNF, 2.5 or 50 micrograms/mouse, IV), interleukin-1 (IL-1 beta, 2.5 micrograms/mouse, IV), interferon-gamma (IFN-gamma, 2.5 micrograms/mouse, IV), or their combination at 2.5 micrograms each. In addition to LPS, only TNF at the highest dose induced pulmonary edema 24 hours later. LPS-induced pulmonary edema was partially inhibited by anti-IFN-gamma antibodies but not by anti-TNF antibodies, anti-IL-1 beta antibodies, or IL-1 receptor antagonist (IL-1Ra). 相似文献