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1.
Twin studies suggest that parent ratings of temperament exaggerate differences between twins. The present study examined whether such contrast effects also operate for nontwin siblings. The activity level (AL) and shyness of 95 nontwin sibling pairs (ages 3 to 8 years) were assessed via parent ratings and objective measures (actigraph and observer ratings). Siblings showed no resemblance in either parent-rated AL or shyness; however, sibling resemblance for actigraph AL and observer-rated shyness was substantial. Thus, parents do contrast their nontwin siblings when rating these 2 temperament dimensions. Moreover, the importance of sibling differences in temperament to the sibling relationship and differential maternal treatment varied across the different measures of AL and shyness, suggesting that parent perceptions may play a role in these associations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
This paper examines Total Quality Management (TQM) as defined by Dr. W. Edwards Deming including Deming's fourteen points and explains how the United States' Department of Defense (DOD) defines TQM and why TQM is necessary. It also covers how the DOD is planning on implementing TQM and the policy that has been established as guidance in the implementation process.  相似文献   
3.
Kinetics of the reaction between bis(4-isocyanatocyclohexyl)methane, H-MDI, and n-butanol was studied in toluene at 100°C. Effects of various catalysts, such as Hg(CH3COO)2, Zn(CH3COO)2 · 2H2O, SnCl4 · 5H2O, and dibutyltindilaurate on the reaction rate and kinetics were also investigated. Reactions were followed by determining the unreacted isocyanate as a function of reaction time, using the standard dibutylamine back titration method. All catalysts seem to be very effective in increasing of the rate of the reaction compared to the uncatalyzed system. Depending on the initial stoichiometric ratio of (NCO) and (OH) and the concentration of the catalyst used, it seems possible to have preferential catalysis of the primary reaction between (NCO) and (OH) over the side reactions.  相似文献   
4.
We have demonstrated the utility of microbeam-Rutherford BackScattering (μ-RBS) in spatially resolved studies of operational plasma effects on the interior surfaces of plasma flat panel displays manufactured by Photonics Imaging. The experiments were performed at the Sandia Nuclear microprobe using a 2.8 MeV He beam with an average beam spot size of less than 8 μm. The interior surface of the top panes of the flat panels is composed of approximately 800 nm of MgO on top of a 2000 nm thick PbO layer. μ-RBS of sample panels operated under varying conditions measured changes in the surface MgO film thickness due to plasma erosion and redeposition as accurately as ± 1.5 nm. The high accuracy in the MgO thickness measurement was achieved by inferring the MgO thickness from the shift of the Pb front edge in the RBS spectrum. An estimate for the thickness accuracy as a function of the acquired statistics is presented. The surface of the flat panels' bottom panes is also comprised of MgO on top of PbO. However, troughs 100 μm wide by 10 μm deep were partially filled with phosphor and cover the entire width of the surface. This leaves only 100 μm long sections of MgO within the trough exposed. Using μ-RBS, we were able to analyze the surface composition of these regions.  相似文献   
5.
Several scaled models have been used to determine the contributions of various waveguide mount parameters to the embedding impedance of a mm-wave SIS mixer. Measured effects of waveguide height, substrate orientation and width, junction location, lead inductance and RF-filter impedance are presented and discussed.  相似文献   
6.
A novel system for mammary epithelial cell culture   总被引:5,自引:0,他引:5  
A method is described for the isolation and density gradient enrichment of mammary epithelial fragments from pregnant, nonlactating bovine tissue. Immunocytochemical analysis prior to and following culture revealed specific staining with antibodies to keratin, indicating that these cells are epithelial in nature. Fragments enriched for epithelium could be stored in liquid nitrogen for extended periods prior to culture. When cast within a three-dimensional matrix of collagen gel, the mammary fragments grew as branching, duct-like structures and displayed a 4-fold increase in cell number during 10 to 12 d of culture.  相似文献   
7.
Investigated the hypothesis that as group tasks pose greater requirements for member interdependence, communication media that transmit more social context cues will foster group performance and satisfaction. 72 3-person groups of undergraduates worked in either computer-mediated or face-to-face meetings on 3 tasks with increasing levels of interdependence: an idea-generation task, an intellective task, and a judgment task. Results showed few differences between computer-mediated and face-to-face groups in the quality of the work completed but large differences in productivity favoring face-to-face groups. Analysis of productivity and of members' reactions supported the predicted interaction of tasks and media, with greater discrepancies between media conditions for tasks requiring higher levels of coordination. Results are discussed in terms of the implications of using computer-mediated communication systems for group work. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
A study concerning the effect of fiber orientation on the thermal conductivity of a uniaxial carbon-fiber-reinforced borosilicate glass was conducted. For thin specimens, and thick specimens with specimen sides cut parallel to the fiber direction, the dependence of thermal conductivity on fiber orientation showed excellent agreement with theoretical behavior predicted for a composite infinite in extent. In contrast, the thermal conductivity data for rectangular thick specimens fell well below the data for the thin and angled specimens. For fiber orientation of 45° and higher, at which the heat was directed toward the side of the specimen rather than across, the thermal conductivity values showed excellent agreement with theoretical behavior predicted for a finite composite strip with insulated sides.  相似文献   
9.
The accepted model of color naming postulates that 11 “basic” color terms representing 11 common perceptual experiences show increased processing salience due to a theorized linkage between perception, visual neurophysiology, and cognition. We tested this theory, originally proposed by Berlin and Kay in 1969. Experiment 1 tested salience by comparing unconstrained color naming across two languages, English and Vietnamese. Results were compared with previous research by Berlin and Kay, Boynton and Olson, and colleagues. Experiment 2 validated our stimuli by comparing OSA, Munsell, and newly rendered “basic” exemplars using colorimetry and behavioral measures. Our results show that the relationship between the visual and verbal domains is more complex than current theory acknowledges. An interpoint distance model of color‐naming behavior is proposed as an alternative perspective on color‐naming universality and color‐category structure. © 2003 Wiley Periodicals, Inc. Col Res Appl, 28, 113–138, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.10131  相似文献   
10.
This article reviews the evidence and theory pertaining to a form of perspective-taking failure--a difficulty in setting aside the privileged information that one knows to be unavailable to another party. The authors argue that this bias (epistemic egocentrism, or EE) is a general feature of human cognition and has been tapped by 2 independent and largely uncommunicating research traditions: the theory-of-mind tradition in developmental psychology and, with more sensitive probes, the "heuristics and biases" tradition in the psychology of human judgment. This article sets the stage for facilitating communication between these traditions as well as for the recognition of EE's breadth and potential interdisciplinary significance. The authors propose a life-span account and a tentative taxonomy of EE; and they highlight the interdisciplinary significance of EE by discussing its implications for normative ethics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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