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11.
Reports a meta-analysis comparing the size of semantic priming effects on young and older adults' lexical decision and pronunciation latency. The analysis included 15 studies with 49 conditions varying the semantic relatedness of a prime stimulus (single word or whole sentence) and a target word. An effect-size analysis on the difference between young and older adults' semantic priming effect (unrelated minus related latency) indicated that semantic priming effects are reliably larger for older than for young adults. There was no evidence for nonhomogeneity in this age difference across the different conditions. The relationship between young and older adults' semantic priming effects was described by a function with a positive intercept and a slope of 1.0. This pattern of findings favors aging models postulating process-specific slowing rather than general cognitive slowing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
12.
TheSpecial Issue on Applications of Temporal Models raises many issues of time: What are the important properties of time? How can time be best represented? How can one reason about time-dependent properties? What are the important directions of temporal research? This introductory piece very briefly surveys the current wide variety of temporal models, temporal reasoning methods, and applications to time-varying phenomena. Promising areas of investigation such as the verification of concurrent systems, knowledge-base representation methods, and dealing with theFrame Problem pass in fleeting review. Brief introductions to each of the works in the volume close the section.  相似文献   
13.
The addition of palladium to a 4130 steel reduces its sensitivity to stress corrosion cracking and to hydrogen-induced cracking. The atom probe field-ion microscope has been used to study the microstructure and microchemistry of these palladium-modified 4130 steels with particular emphasis on the distribution of palladium between the various phases and internal interfaces. The palladium was found to segregate to the ferrite-ferrite lath boundaries to form a mono-atomically thick adsorbate layer. Palladium-manganese precipitates both at the lath boundaries and in the ferrite matrix were also detected. Most of the palladium was found to remain in solution in the ferrite.  相似文献   
14.
A fast and near exact modal analysis is presented to obtain the propagation constants and electric field profiles for dielectric multilayered channel (rib) waveguides. Calculations are performed for a particular channel configuration and found to be in excellent agreement with those obtained using the finite difference method  相似文献   
15.
This letter reports the design and fabrication of 4H-SiC bipolar junction transistors with both high voltage (>1kV) and high dc current gain (/spl beta/=32) at a collector current level of I/sub c/=3.83A (J/sub c/=319 A/cm/sup 2/). An Al-free base ohmic contact has been used which, when compared with BJTs fabricated with Al-based base contact, shows clearly improved blocking voltage. A specific on-resistance of 17 m/spl Omega//spl middot/cm/sup 2/ has been achieved for collector current densities up to 289 A/cm/sup 2/.  相似文献   
16.
Evaluated the efficacy of outpatient group treatment of chronic pain and the effect of spouse involvement in treatment in chronic pain patients ranging in age from 23 to 69 yrs who were randomly assigned to couples group treatment (n?=?17), patient-only group treatment (n?=?14), or waiting-list controls (n?=?12). 29 Ss had low back pain; the remaining Ss reported pain in the knee, arm, leg, hip, head, and phantom limb. The Ss completed the MMPI—168 and measures of health-related psychosocial and physical dysfunction and marital satisfaction. Results indicate that the 16-hr cognitive-behavioral program produced reductions in pain, somatization, spouse-observed pain behavior, physical and psychosocial dysfunction, spouse-rated dysfunction, and utilization of health care resources. Depression was not affected by treatment. Spouse involvement did not facilitate response to treatment on any variables. Also, Ss in the individual condition only showed improved marital satisfaction. All treatment gains were maintained at 3-mo to 7-mo follow-ups. Results indicate that brief outpatient treatment can significantly ameliorate chronic pain problems, and spouse involvement is not essential for a positive response to treatment. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The edentulous ridge expansion has been introduced in recent years to reestablish an appropriate alveolar ridge width. This technique consists of the placement of implants in the space formed after the dislocation of the buccal plate in a labial direction. In guided bone regeneration, the quantity of bone regenerated under the membranes has been demonstrated to be directly related to the amount of the space under the membranes. This space can diminish as a result of membrane collapse. To avoid this problem, a new technique of edentulous ridge expansion, which involved the use of a titanium mesh barrier to protect the regenerating tissues and to achieve a rigid fixation of the bone segments, was used in association with autologous bone in 25 patients. At second-stage surgery in all patients, it was possible to see tissue, under the mesh, that had the macroscopic characteristics of mature bone and was superficially covered by a thin soft tissue layer. The microscopic examination showed that all autologous bone particles were embedded in newly formed bone. The use of a rigid mesh can assist bone regeneration in non-space-making defects, since it probably does not interfere with the blood flow to the underlying tissues because of the presence of microholes within the mesh.  相似文献   
19.
Several factors promote the progression of renal disease, including glomerular hypertension and hypertrophy, molecular factors such as cytokines and growth hormones, proteinuria, acidosis, and hyperlipidemia. Regardless of the underlying etiology, many patients with chronic renal insufficiency will ultimately require kidney replacement therapy. Your goal is to delay the progression of renal failure, mainly through aggressive control of blood pressure. Other possible interventions include protein restriction, bicarbonate therapy, and lipid-lowering drugs.  相似文献   
20.
The process described as “roll-drawing” has been applied to commercial extruded sheets of isotactic polypropylene (M?n = 70,900). Preheated billets were drawn into thin, clear, transparent sheets in a single pass, producing uniaxial orientation of the polymer molecules in the draw direction. At the maximum draw ratio of 20, the ultimate tensile strength and Young's modulus in the draw direction were 0.5 GPa and 20 GPa respectively. The mechanical properties transverse to the draw direction were virtually unchanged. The theory of fiber reinforcement for unidirectional anisotropic plates was applied to interpret the orientation dependence of the stress-strain behavior of the drawn sheets. From these results, it was estimated that the mechanical properties of biaxially laminated polypropylene sheets equaled the performance of aramid and carbon fiber composites, The roll-drawing process appears to be economically attractive for the production of ultra-high modulus crystalline thermoplastics in sheet form having excellent uniaxial or biaxial properties.  相似文献   
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