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81.
Examined hemodynamic responses to systematic variations in occupational stress using ambulatory blood pressure monitors. Heart rate, systolic blood pressure, diastolic blood pressure, rate–pressure product, and mood states were measured before, during, and after low-stress (lecture) and high-stress (examination) work in 44 healthy White male medical students. The lecture day was characterized by stable patterns of cardiovascular activity across all 3 periods. Hemodynamic activity and reports of activation and distress were greater on the examination day than on the lecture day. Cardiovascular activity during the pre-examination period was as high as that seen during the examination period itself, indicating an anticipatory stress effect. Pressor activity decreased after the examination, although some residual chronotropic activity was seen. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
Describes a unique multidisciplinary division in which 8 clinical programs are all administered by psychologists working in a university medical center setting. The increasingly complex environment of a university medical center is discussed in terms of academic mission, competitiveness of health care, and professional roles. The development of this division is reviewed in relation to a number of critical issues, such as organizational structure, academic vs clinical demands, business operations, and 1 version of a scientist–practitioner model in practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
83.
This study looked at the quality and quantity of interactions between fathers and their firstborn 5-year-olds from the perspective of the family as a developmental interdependent system. The goals were to identify predictors of men's parenting from men's own adaptation (direct effects) and from their wives' characteristics (indirect effects), both measured during the expectancy. Twenty-three families from the Boston University Pregnancy and Parenthood Project made up the sample. Measures included self-report scales, observations, and semistructured interviews. Several of men's psychological characteristics, particularly their autonomy and job satisfaction, predicted their play time and the quality of their interactions with their children. Women's autonomy, occupation, and age in the expectancy predicted men's caretaking and weekday time involvement with their 5-year-olds. We suggest that the findings can best be explained by the concepts of complementarity and identification. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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85.
Vandermonde and resultant matrices: An abstract approach  相似文献   
86.
87.
Coating of 0.65Pb(Mg1/3Nb2/3)O3–0.35PbTiO3 (PMN–PT) relaxor ferroelectrics by a sol–gel method is followed by growth of epitaxial SrRuO3 (SRO) metallic oxide electrodes on SrTiO3 (STO) single-crystal substrate by pulsed laser deposition. High-quality PMN–PT films on SRO with preferred growth orientation were successfully fabricated by controlling the operation parameters. Structural properties of relaxor ferroelectric PMN–PT thin films on SRO/STO substrates have been studied by X-ray diffraction (XRD), transmission electron microscopy (TEM) and atomic force microscopy (AFM). In-plane and out-of-plane alignments of the heterostructure are confirmed and the structural twinning of the materials are also revealed.  相似文献   
88.
The technology to create secure digital signatures is proven and workable on PC-level hardware, as well as on mainframes. the issues currently restraining widespread use of digital signatures are primarily legal. This tutorial survey first identifies the functions a digital signature should ideally perform by tracing an example Internet-based electronic business transaction. After an overview of the technology that provides the required functionality, this article presents the current legal status of digital signature use, including a number of unresolved liability issues, and summarizes some precautions for digital signature use.  相似文献   
89.
Platinum-ruthenium electrodes (PtxRu1-x) have been prepared by electrochemical and electroless deposition and investigated as catalysts for the oxidation of methanol in acidic solutions. PtxRu1-x deposits were electrochemically deposited from acidic chloride electrolytes at potentials between −0.46 and 0.34 V (vs. NHE). The composition of the electrodeposit was estimated by energy dispersive X-ray spectroscopy and is a strong function of the electrode potential. An empirical model for the deposition process is presented and kinetic parameters are estimated and discussed. Also, the methanol oxidation activity of the PtxRu1-x catalysts was characterized by cyclic voltammetry in 1.0 M CH3OH, 1.0 M H2SO4 solutions. Electroless PtxRu1-x samples were prepared in a modified Leaman bath with hydrazine dihydrochloride as the reducing agent. The kinetic results for the electrochemical deposition of PtxRu1-x were directly applied and the deposition potential was estimated as approximately 0.40 V.  相似文献   
90.
Children with attention-deficit/hyperactivity disorder (ADHD) are at risk for adverse outcomes such as substance abuse and criminality, particularly if they develop conduct problems. Little is known about early predictors of the developmental course of conduct problems among children with ADHD, however. Parental psychopathology and parenting were assessed in 108 children who first met Diagnostic and Statistical Manual of Mental Disorders (4th ed.) criteria for ADHD at 4-7 years old. When demographic variables and baseline ADHD and conduct problems were controlled, maternal depression predicted conduct problems 2-8 years following the initial assessment, whereas positive parenting during the structured parent- child interaction task predicted fewer future conduct problems. These findings suggest that maternal depression is a risk factor, whereas early positive parenting is a protective factor, for the developmental course of conduct problems among children with ADHD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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