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81.
Age differences in memory performance were studied in a probability sample of a cross-section of 1,491 adults living in the Detroit metropolitan area, with an oversample of those age 60 and older. Both a recall and a recognition measure were adapted to the survey context by querying respondents about the nature of the questions asked in an immediately preceding interview. Subjective memory assessment was also measured, using global memory ratings performed by the respondent, his or her spouse, and the interviewer. A clear, age-related decline in memory performance was found in this population sample. Subjective memory assessment also declined across age groups, but the relation was weaker. On the basis of multiple regression analyses of the recognition measure and the respondent's self-rated memory, which were judged to have the best measurement qualities, a substantial part of these age differences can be accounted for by differences in sociodemographic composition between age groups, by cognitive functioning and physical health. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
A monolithic ±5-1/2-digit BiMOS analog-digital converter that achieves integral integrity within two counts over the range -2 V to +2 V and noise error for any single reading within ±1 count is described. The part uses four noncritical external passive components; the reference voltage is also provided externally. The converter uses a three-pass algorithm with a modified dual-slope integration and subsequent residue multiplication steps. It has been integrated on a BiMOS process based on a production 4-μm CMOS process with one mask added and the starting material polarity changed  相似文献   
83.
Objective: To evaluate the theory of planned behavior (TPB) as a framework for understanding exercise motivation during and after Phase 2 cardiac rehabilitation (CR). Design and Participants: Patients (57 men and 24 women) completed a TPB questionnaire that included attitudes, subjective norms, perceived behavioral control, and exercise intentions pre- and post-Phase 2 CR. Results: During Phase 2 CR, regression analyses indicated that attitude, subjective norm, and perceived behavioral control (PBC) explained 38% of the variance in exercise intention while intention explained 23% of the variance in exercise adherence. At postrehabilitation follow-up, attitudes, subjective norm, and PBC explained 51 % of the variance in exercise intention while intention explained 23% of the variance in exercise adherence. Conclusion: The TPB is a useful framework for understanding exercise intentions and behavior both during and after Phase 2 CR. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
85.
This study uses a feminist framework of masculine cultural hegemony to examine the representation of women in two newspapers—a medium-sized newspaper (Study 1) and a larger newspaper (Study 2). Surveys gauged news staff and news reader perceptions of female representation in news content to determine if perceptions matched content-analysis findings. Content-analysis results revealed a greater proportion of males than females in both content and photos for both studies. Female staffers were more likely than their male counterparts to perceive this disparity, and news readers perceived an even greater disparity than the news staff. News staffs were less likely to perceive disparities in the editorial, travel, and entertainment sections. We discuss the findings in relation to cultural hegemony and the representation of women in the news.  相似文献   
86.
The present study evaluated the characteristics of research on child and adolescent psychotherapy. Published studies (N?=?223) of psychotherapy from 1970 to 1988 were codified to characterize research, clinical, and methodological characteristics. The major results indicate that (1) treatment research focuses almost exclusively on the impact of treatment techniques with scant attention to influences (child/adolescent, parent, family, therapist) that may moderate outcome and (2) several characteristics of the children/adolescents and methods of treatment delivery and approaches depart markedly from those evident in the practice of treatment. Priorities for treatment research to place clinical practice on firmer empirical footing are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
87.
Studies of the copolymerization of CO2 and epoxides have been the staple of our group's research program for the better part of a decade now. During that time, the incorporation of attenuated total reflectance Fourier transform infrared (ATR/FTIR) spectroscopy has greatly enhanced the kinetic and mechanistic investigations performed. However helpful, there are some difficulties, e.g., phase partitioning, that we have discovered and overcome in that same time period. The greatest step forward was achieved by the incorporation of 2-(3,4-epoxycyclohexyl)-ethyltrimethoxysilane (TMSO) as an epoxide for performing accurate kinetic studies. Herein, we discuss the development of this technique into one of the mainstays within our laboratories, highlighted by our most recent catalyst system that utilizes (salen)CrIIIX/cocatalyst where salen: N,N′-bis(salicylidene)-1,2-ethylenediimine, X: Cl or N3 and cocatalyst: N-methylimidazole, phosphines and PPN+ salts. Through altering the cocatalyst, ligand architecture and initiator, this catalyst system has proven to be one of the most industrially viable catalysts currently being studied.  相似文献   
88.
A series of AgBr emulsions has been prepared under controlled pAg conditions from a monodisperse “seed” emulsion, concentrating in those pAg regions where there is a transition from one crystal habit to another. The transition point between cubic and octahedral forms is defined as that tetradecahedron which has equal surface areas of (200) and (111) faces. The second transition point is that pag where precipitating AgBr is diverted to the formation of twinned crystal under the conditions of the experiment. A correlation was made between the observed transition points and the concentrations of the silver complexes in solution.

The effect of crystal habit on sulphur sensitization was studied lIsing a set of cubic, tetradecahedral and octahedral emulsions having the same average grain volumes. The tetradecahedral emulsions were found to be intermediate in their behaviour between cubes and octahedra. The thiosulphate additions required for maximum speed were in the order: octahedral < tetradecahedralecubic.  相似文献   
89.
Computer-based systems that support health care require large controlled terminologies to manage names and meanings of data elements. These terminologies are not static, because change in health care is inevitable. To share data and applications in health care, we need standards not only for terminologies and concept representation, but also for representing change. To develop a principled approach to managing change, we analyze the requirements of controlled medical terminologies and consider features that frame knowledge-representation systems have to offer. Based on our analysis, we present a concept model, a set of change operations, and a change-documentation model that may be appropriate for controlled terminologies in health care. We are currently implementing our modeling approach within a computational architecture.  相似文献   
90.
Supercritical carbon dioxide (scCO2) has been proposed as an effective exfoliating agent for the preparation of polymer‐layered silicate nanocomposites, though there is limited fundamental understanding of this mechanism. This study looks at the interactions of this unique green solvent with three maleated polypropylenes of varying anhydride content and molecular size with an alkyl‐ammonium organoclay. Mixtures of compatibilizers and organoclay were melt‐annealed in a high pressure batch vessel at 200°C and subjected to either a blanket of nitrogen or scCO2 at a pressure of 9.7 MPa. The structures and properties of these melt‐annealed mixtures were characterized by X‐ray diffraction, transmission electron microscopy, Fourier Transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, differential scanning calorimetry, and contact angle measurement. The results indicate that the plasticizing influence of scCO2 aided intercalation and exfoliation for intercalants of moderate molecular size and anhydride content which would otherwise have limited diffusion into the clay galleries. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
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