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41.
Kovera Margaret Bull; Gresham April W; Borgida Eugene; Gray Ellen; Regan Pamela C 《Canadian Metallurgical Quarterly》1997,82(1):178
The authors examined whether expert testimony serves an educational or a persuasive function. Participants watched a simulated sexual abuse trial in which the child witness had been prepared for her testimony (i.e., she was calm, composed, and confident) or unprepared (i.e., emotional, confused, and uncertain). The trial contained different levels of expert testimony: none, standard (i.e., a summary of the research), repetitive (i.e., standard testimony plus a 2nd summary of the research), or concrete (i.e., standard testimony plus a hypothetical scenario linking the research to the case facts) testimony. Repetitive testimony bolstered the child's testimony, whereas concrete and standard testimony did not. Concrete testimony sensitized jurors to behavioral correlates of sexual victimization; standard and repetitive testimony desensitized jurors to these correlates. Implications for the use of procedural innovations in sexual abuse trials are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
A perturbation expansion technique for approximating the three dimensional anisotropic elastic Green's function is presented. The method employs the usual series for the matrix (I–A)-1 to obtain an expansion in which the zeroth order term is an isotropic fundamental solution. The higher order contributions are expressed as contour integrals of matrix products, and can be directly evaluated with a symbolic manipulation program. A convergence condition is established for cubic crystals, and it is shown that convergence is enhanced by employing Voigt averaged isotropic constants to define the expansion point. Example calculations demonstrate that, for moderately anisotropic materials, employing the first few terms in the series provides an accurate solution and a fast computational algorithm. However, for strongly anisotropic solids, this approach will most likely not be competitive with the Wilson-Cruse interpolation algorithm.This research was sponsored by the Exploratory Studies Program of Oak Ridge National Laboratory and the Division of Materials Science, U. S. Department of Energy, under contract DE-AC05-84OR21400 with Lockheed Martin Energy Systems, Inc. 相似文献
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VL Beggs NJ Birkemeyer WC Nugent LJ Dacey GT O'Connor 《Canadian Metallurgical Quarterly》1996,1(4):180-186
BACKGROUND: Early rehospitalization after coronary artery bypass grafting (CABG) is an expensive and frequently adverse outcome. Rehospitalization rates after various surgical procedures have been used as an indicator of quality of care. Determining the extent to which rehospitalization rates reflect patient case mix and severity of illness rather than quality of care requires detailed information regarding the patients, the care they received, and the reasons for their rehospitalization. METHODS: We conducted a nested case control study comparing 110 CABG patients who were rehospitalized within 30 days after discharge with 224 control patients. Control patients were randomly selected from patients undergoing CABG during the same time frame as the cases and were matched on age, gender, and priority of surgery. A detailed chart review provided information regarding treatment in the postsurgical period, in addition to the preoperative information collected on all CABG patients as part of an ongoing regional prospective study. RESULTS: The overall rehospitalization rate was 13.8%. The most common reasons for rehospitalization included: wound infection (19%), atrial fibrillation (13%), pleural effusion (11%), and thromboembolic event (10%). Preoperative severity of illness and comorbidity accounted for 24% of the total variance. After adjustment for these factors, discharge hematocrit less than 30% (OR = 2.01, p = 0.018) and several discharge medications including: antiarrhythmics (OR = 3.26, p = 0.047), diuretics (OR = 2.18, p = 0.055), beta blockers (OR = 0.44, p = 0.036), and long length of stay (more than 7 days; OR = 2.09, p = 0.029) were the most important predictors of rehospitalization risk. CONCLUSIONS: Although the reasons for rehospitalization after CABG are heterogeneous and related to patient severity of illness as well as comorbid status, several of the most common are potentially preventable and related to quality of care. Rehospitalization was not related to early discharge. 相似文献
45.
A fast parasitic-insensitive continuous-time filter and equalizer integrated circuit that uses an active integrator is described. Circuit techniques for excess-phase cancellation and for setting the corner-frequency of the filter and equalizer are also described. These techniques result in a filter and equalizer chip with performance independent of process, supply, and temperature without employing phase-lock loops. The 20-MHz sixth-order Bessel filter and second-order equalizer operate from 5 V and generate only 0.24% (-52 dB) of total harmonic distortion when processing 2-Vpp differential output signals. The device is optimized to limit high-frequency noise and to amplitude equalize the data pulses in hard disk read-channel systems. The device supports data rates of up to 36 Mb/s and is built in a 1.5-μm, 4-GHz BiCMOS technology 相似文献
46.
Recently theories of vortex fluctuations in two-dimensional superconducting films have been compared to the experimentally determined power law dependence of voltage on current and to the temperature-dependent resistance in small applied fields. Here an alternative interpretation of the power law and a practical difficulty of flux pinning for measurements in small fields are pointed out. To illustrate these points, experimental examples are presented for very homogeneous granular aluminum films. 相似文献
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48.
M Nishikawa P Chowdhury K Takaori GT Blevins PL Rayford 《Canadian Metallurgical Quarterly》1998,9(2):26-30
Excitability of functionally different alpha-motoneurons was studied in 62 patients with gunshot injuries of nervous trunks of lower extremities both before and during process of rehabilitation by means of physical factors. The correlation of reactions of spinal cord motoneurons and the degree of injuries of nervous trunks was observed. Neuroapraxia of nervous trunks was accompanied by multidirectional alterations in reflex activity of large and small alpha-motoneurons. It was depressed in axonothermesis and lost in simultaneous full anatomic interruption of ischiatic nerve and trunks of both fibular and tibial nerves. Under influence of physical factors the function of motoneurons was normalized in neuroapraxia and was improved in axonothermesis of nervous trunks. 相似文献
49.
Wave-front curvature as a cause of slow conduction and block in isolated cardiac muscle 总被引:1,自引:0,他引:1
C Cabo AM Pertsov WT Baxter JM Davidenko RA Gray J Jalife 《Canadian Metallurgical Quarterly》1994,75(6):1014-1028
We have investigated the role of wave-front curvature on propagation by following the wave front that was diffracted through a narrow isthmus created in a two-dimensional ionic model (Luo-Rudy) of ventricular muscle and in a thin (0.5-mm) sheet of sheep ventricular epicardial muscle. The electrical activity in the experimental preparations was imaged by using a high-resolution video camera that monitored the changes in fluorescence of the potentiometric dye di-4-ANEPPS on the surface of the tissue. Isthmuses were created both parallel and perpendicular to the fiber orientation. In both numerical and biological experiments, when a planar wave front reached the isthmus, it was diffracted to an elliptical wave front whose pronounced curvature was very similar to that of a wave front initiated by point stimulation. In addition, the velocity of propagation was reduced in relation to that of the original planar wave. Furthermore, as shown by the numerical results, wave-front curvature changed as a function of the distance from the isthmus. Such changes in local curvature were accompanied by corresponding changes in velocity of propagation. In the model, the critical isthmus width was 200 microns for longitudinal propagation and 600 microns for transverse propagation of a single planar wave initiated proximal to the isthmus. In the experiments, propagation depended on the width of the isthmus for a fixed stimulation frequency. Propagation through an isthmus of fixed width was rate dependent both along and across fibers. Thus, the critical isthmus width for propagation was estimated in both directions for different frequencies of stimulation. In the longitudinal direction, for cycle lengths between 200 and 500 milliseconds, the critical width was < 1 mm; for 150 milliseconds, it was estimated to be between 1.3 and 2 mm; and for the maximum frequency of stimulation (117 +/- 15 milliseconds), it was > 2.5 mm. In the transverse direction, critical width was between 1.78 and 2.32 mm for a basic cycle length of 200 milliseconds. It increased to values between 2.46 and 3.53 mm for a basic cycle length of 150 milliseconds. The overall results demonstrate that the curvature of the wave front plays an important role in propagation in two-dimensional cardiac muscle and that changes in curvature may cause slow conduction or block. 相似文献
50.