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122.
Takagi S Frukhtbeyn S Chow LC Sugawara A Fujikawa K Ogata H Hayashi M Ogiso B 《Journal of research of the National Institute of Standards and Technology》2010,115(4):267-276
This study reports for the first time in vitro and in vivo properties of fluorapatite (FA)-forming calcium phosphate cements (CPCs). The experimental cements contained from (0 to 3.1) mass % of F, corresponding to presence of FA at levels of approximately (0 to 87) mass %. The crystallinity of the apatitic cement product increased greatly with the FA content. When implanted subcutaneously in rats, the in vivo resorption rate decreased significantly with increasing FA content. The cement with the highest FA content was not resorbed in soft tissue, making it the first known biocompatible and bioinert CPC. These bioinert CPCs might be useful for applications where slow or no resorption of the implant is required to achieve the desired clinical outcome. 相似文献
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A central question in psycholinguistic research is how listeners isolate words from connected speech despite the paucity of clear word-boundary cues in the signal. A large body of empirical evidence indicates that word segmentation is promoted by both lexical (knowledge-derived) and sublexical (signal-derived) cues. However, an account of how these cues operate in combination or in conflict is lacking. The present study fills this gap by assessing speech segmentation when cues are systematically pitted against each other. The results demonstrate that listeners do not assign the same power to all segmentation cues; rather, cues are hierarchically integrated, with descending weights allocated to lexical, segmental, and prosodic cues. Lower level cues drive segmentation when the interpretive conditions are altered by a lack of contextual and lexical information or by white noise. Taken together, the results call for an integrated, hierarchical, and signal-contingent approach to speech segmentation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
126.
The original hypothesis of M. Dixon et al (1990) that highly hypnotizable (HH) Ss process words more automatically than do low hypnotizable (LH) Ss was retested in a paradigm that separated strategic from automatic processes in the Stroop color-naming task. The words red and blue preceded a color patch that was red or blue. Ss were told that the word predicted the opposite color 75% of the time. Automatic and strategic processes were assessed by varying interstimulus interval (ISI) between the word and the color patch. Both HH and LH Ss showed significant strategic effects (faster incongruent-trial, color-naming reaction times [RTs] than congruent-trial RTs at ISIs over 400 msec), but only HH Ss showed significant automaticity (significantly faster congruent-trial RTs than incongruent-trial RTs at 16.7 msec, the lowest ISI). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
127.
Laurence Danlos 《电信纪事》1989,44(1-2):94-100
Automatic generation is a recent domain dedicated to the production of written texts from abstract representations or from numerical data. One way to produce sentences while avoiding the difficulties of automatic generation consists in using pre-recorded texts. However, this method becomes cumbersome when there is a number of pre-recorded texts. It can be improved by allowing them to include variables. Yet, it will be shown that the use of variables requires the pre-recorded sentences to be annotated with linguistic information so that syntactic operations can be applied to them. In fact, the use of variables entails adopting techniques that fall in the domain of automatic generation. Such techniques will be presented briefly. 相似文献
128.
This study operationalizes an existing concept for the categorization of governance approaches for projects. For that the concept's four governance paradigms, based on the overlay of the shareholder–stakeholder orientation with the behavior–outcome control of a project's parent organization are measured. The measurement dimensions were derived from the intersection of governance and organization theory with project management theory, thereby addressing those areas of corporate governance and organizational control that extend into projects. The application of the measurement construct, its validity and reliability are tested through a world-wide questionnaire with 478 responses. Analysis of the responses shows the differences in governance structures for projects by country, project size, and project type. The results are important for managers developing governance structures and academics developing governance theories. 相似文献
129.
Guangxin Tang Minghe Liu Laurence J. Jacobs Jianmin Qu 《Journal of Nondestructive Evaluation》2014,33(2):196-204
When the frequencies of a pair of collinear shear and longitudinal waves satisfy the resonant condition, mixing of these two primary waves generates a third, resonant shear wave that propagates in the direction opposite to the propagating direction of the primary shear wave. In this study, experiments were conducted to demonstrate that the acoustic nonlinearity parameter at the location of the mixing zone can be obtained by measuring the resonant shear wave. Since the location of the mixing zone can be controlled by adjusting the trigger time of the transducers that generate the primary waves, this collinear wave mixing technique enables the scanning of a bar sample to measure the distribution of acoustic nonlinearity along the bar. To demonstrate this scanning capability, bar samples with non-uniform acoustic nonlinearity parameters were fabricated by inducing localized plastic deformation at known locations. Scanning collinear wave mixing tests conducted on such bar samples clearly identified the locations of the plastic zone. These results show that collinear wave mixing is a promising method for scanning the test sample to map out the distribution of localized plastic deformation. 相似文献
130.