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1.
In flash sintering experiments, the thermal history of the sample is key to understanding the mechanisms underlying densification rate and final properties. By combining robust temperature measurements with current-ramp-rate control, this study examined the effects of the thermal profile on the flash sintering of yttria-stabilized zirconia, with experiments ranging from a few seconds to several hours. The final density was maximized at slower heating rates, although processes slower than a certain threshold led to grain growth. The amount of grain growth observed was comparable to a similar conventional thermal process. The bulk electrical conductivity correlated with the maximum temperature and cooling rate. The only property that exhibited behavior that could not be attributed to solely the thermal profile was the grain boundary conductivity, which was consistently higher than conventional in flash sintered samples. These results suggest that, during flash sintering, athermal electric field effects are relegated to the grain boundary.  相似文献   
2.
Analyses of human object recognition abilities led to the hypothesis that 2 kinds of spatial relation representations are used in human vision. Evidence for the distinction between abstract categorical spatial relation representations and specific coordinate spatial relation representations was provided in 4 experiments. These results indicate that Ss make categorical judgments—on/off, left/right, and above/below—faster when stimuli are initially presented to the left cerebral hemisphere, whereas they make evaluations of distance—in relation to 2 mm, 3 mm, or 1 in. (2.54 cm)—faster when stimuli are initially presented to the right cerebral hemisphere. In addition, there was evidence that categorical representations developed with practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.

Background  

Bioelectrical Impedance (BIA) derived phase angle is increasingly being used as an objective indicator of nutritional status in advanced cancer. Subjective Global Assessment (SGA) is a subjective method of nutritional status. The objective of this study was to investigate the association between BIA derived phase angle and SGA in advanced colorectal cancer.  相似文献   
4.
Premature and ill term babies born in regional Australia must be moved to another hospital with Neonatal Intensive Care Unit (NICU) facilities. Transferred pre-term and critically ill term babies have higher mortality rates and much higher rates of long term disability than similar babies born in hospitals with NICU facilities. This paper details the Bush Babies Broadband project that aims to significantly improve the quality of treatment for babies born in rural, remote as well as urban areas by providing the first on-demand virtual NICU architecture in Australia. Real-time data collected from medical monitors and ventilators attached to the baby, audiovisual streams and static physiological data such as X-ray images are transmitted to the consulting Neonatologist to gain a better picture of the patient's condition than is currently available. The key contribution of this significant research is the infrastructure providing a mechanism for Neonatologists to receive information directly from a regional hospital, thereby preventing, in some cases, the immediate need to move the baby. A key benefit of this framework is that it is available to link regional hospitals with the supporting NICU Neonatologist ‘on demand’ eliminating the need to establish permanent point to point connections. This paper further describes the application of that architecture to a specific pilot connecting the Bathurst regional hospital with Neonatologists within the NICU at Nepean Hospital, Penrith Australia.  相似文献   
5.
Understanding how aging influences cognition across different cultures has been hindered by a lack of standardized, cross-referenced verbal stimuli. This study introduces a database of such item-level stimuli for both younger and older adults, in China and the United States, and makes 3 distinct contributions. First, the authors specify which item categories generalize across age and/or cultural groups, rigorously quantifying differences among them. Second, they introduce novel, powerful methods to measure between-group differences in freely generated ranked data, the rank-ordered logit model and Hellinger Affinity. Finally, a broad archive of tested, cross-linguistic stimuli is now freely available to researchers: data, similarity measures, and all stimulus materials for 105 categories and 4 culture-by-age groups, comprising over 10,000 fully translated unique item responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
Few studies have documented public perceptions of environmental health risks from exposure to overhead transmission lines. In particular, little information has been provided on the impact of worry on symptom prevalence in residents living adjacent to high voltage transmission lines. The current study assessed symptom prevalence and worry in 152 Orange County female residents living either adjacent to overhead transmission lines or one block away. Forty-five percent of the respondents were either very worried or somewhat worried about the transmission lines and 55% were slightly worried or not worried at all. Results indicated that for those who did not live on the easement level of worry did not affect the prevalence of health problems. For those who lived on the easement, the most worried respondents were more likely to report health problems. Disclosure of health problems may depend more on individuals' level of worry about rather than proximity to overhead transmission lines. Possible limitations of this study include personality variables such as hypochondriasis which were not assessed, recall bias, and social desirability. The homogeneity of subjects may also limit the generalizability of findings.  相似文献   
7.
11B and 27Al magic angle spinning nuclear magnetic resonance (MAS NMR) spectra of alkaline-earth boroaluminate glasses show that the structure of these glasses are far more complicated than previously thought. The relative concentrations of 3- and 4-coordinated boron vary as found by previous investigators using continuous-wave NMR methods, but the 27Al NMR spectra indicate the presence of Al in 4-, 5-, and 6-fold coordination, in contrast to previous assignments. Analysis of the data based on local charge balance considerations provides a qualitative model that correctly predicts compositional variations of the NMR peak intensities and 27Al chemical shifts for a wide range of boroaluminate glass compositions.  相似文献   
8.
Findings from several studies have indicated that the scientist-practitioner model (which stresses the integration of research into clinical practice) is infrequently adopted by practicing clinical psychologists. Although many hypotheses have been offered, there have been no empirical examinations of the reasons why clinicians infrequently engage in research. In this study, 79 practicing clinical psychologists completed a questionnaire focusing on perceived impediments to clinical research. A number of inhibiting factors were identified, but the intrinsic and extrinsic contingencies associated with the conduct of research were most salient. Other concerns included ethics, the impact of research on the clinical process, and the unavailability of appropriate research designs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
The effectiveness of overlearning in enhancing performance has been acknowledged by researchers within the training community for years. In spite of this general consensus, the empirical basis for this claim is often not clear. This article presents a meta-analysis of the effects of overlearning on retention. Results indicate that overlearning produces a significant effect on retention of moderate overall magnitude and that the effect of overlearning on retention is moderated by the degree of overlearning, type of task, and length of retention period. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
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