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901.
A phase-transformation-induced hardening effect is reported in Zn–22Al (Al: 22?wt.%) alloys. The Zn–22Al specimens were held at 300?°C for 10?h and then quenched in water. A hardening effect took place in subsequent artificial aging at 100–200?°C, which was accompanied by a phase decomposition of a soft α 2 phase and a grain coarsening. The phase-transformation-induced hardening affects the hardness more than the grain-coarsening-induced softening, which leads to the age-hardening phenomenon. 相似文献
902.
Feng Du Jiaoyan Yang Yue Yin Kan Zhang Richard A. Abrams 《Psychonomic bulletin & review》2013,20(5):944-950
Converging evidence has shown that onset capture can be completely eliminated by the demands of a concurrent task and during the attentional blink. In the present study, we investigated contingent capture during the attentional blink. We found that contingent capture was attenuated, or even completely eliminated, during the “blink” time of the attentional blink. These results indicate that contingent capture requires limited attentional resources. 相似文献
903.
We examined the limits of visual resolution in natural scene viewing, using a gaze-contingent multiresolutional display having a gaze-centred area-of-interest and decreasing resolution with eccentricity. Twelve participants viewed high-resolution scenes in which gaze-contingent multiresolutional versions occasionally appeared for single fixations. Both detection of image degradation (five filtering levels plus a no-area-of-interest control) in the gaze-contingent multiresolutional display, and eye fixation durations, were well predicted by a model of eccentricity-dependent contrast sensitivity. The results also illuminate the time course of detecting image filtering. Detection did not occur for fixations below 100 ms, and reached asymptote for fixations above 200 ms. Detectable filtering lengthened fixation durations by 160 ms, and interference from an imminent manual response occurred by 400-450 ms, often lengthening the next fixation. We provide an estimate of the limits of visual resolution in natural scene viewing useful for theories of scene perception, and help bridge the literature on spatial vision and eye movement control. 相似文献
904.
We investigated whether similarity among faces could modulate the face-capturing effect in change detection. In Experiment 1, a singleton search task was used to demonstrate that a face stimulus captures attention and the odd-one-out hypothesis cannot account for the results. Searching for a face target was faster than searching for a nonface target no matter whether distractor–distractor similarity was low or high. The fast search, however, did not lead to a face-detection advantage in Experiment 2 when the pre- and postchange faces were highly similar. When participants in Experiment 3 had to divide their attention between two faces in stimulus displays for change detection, detection performance was worse than performance in detecting nonface changes. The face-capturing effect alone is insufficient to produce the face-detection advantage. Face processing is efficient but its effect on performance depends on the stimulus–task context. 相似文献
905.
Bernhard Angele Timothy J. Slattery Jinmian Yang Reinhold Kliegl Keith Rayner 《Visual cognition》2013,21(6):697-707
The boundary paradigm (Rayner, 1975) with a novel preview manipulation was used to examine the extent of parafoveal processing of words to the right of fixation. Words n+1 and n+2 had either correct or incorrect previews prior to fixation (prior to crossing the boundary location). In addition, the manipulation utilized either a high or low frequency word in word n+1 location on the assumption that it would be more likely that n+2 preview effects could be obtained when word n+1 was high frequency. The primary findings were that there was no evidence for a preview benefit for word n+2 and no evidence for parafoveal-on-foveal effects when word n+1 is at least four letters long. We discuss implications for models of eye-movement control in reading. 相似文献
906.
While Hoge Intrinsic Religiosity Scale and the Duke University Religion Index have gained popularity in the field of religion and mental health, it remains unknown whether these scales are optimal measures of religiosity in the Chinese culture. This study is to provide some evidence to support the use of the Chinese versions of Hoge Intrinsic Religiosity Scale and the Duke University Religion Index. The data were from a community-based sample of 1039 Chinese women, 18–34 years old, in rural China. Reliability tests were performed on the two religiosity scales. Internal consistency analysis showed excellent correlation coefficients for most of the items. In addition, factor analysis produced two factors for the Hoge Intrinsic Religiosity Scale, a result consistent with previous findings in the Western, predominantly Christian cultures and societies. Moreover, our findings showed statistically significant correlations between the two religiosity scales and mental health outcomes, even though the strength of correlation between the Hoge Intrinsic Religiosity Scale and mental health outcomes appeared to be stronger. In sum, this study suggests that both the Hoge Intrinsic Religiosity Scale and the Duke University Religion Index should be appropriate instruments for detecting and measuring religiosity in the Chinese context. 相似文献
907.
Jing Chen Sandra Hale Joel Myerson 《Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition》2013,20(2):122-133
Age-related differences in visuospatial working memory were examined in 69 young adults and 49 older adults exposed to three pairs of tasks. Each pair consisted of one task involving information about the form or appearance of items and another task involving information about item locations. The first pair of tasks manipulated retention interval and required maintaining information about one item. The second pair also manipulated retention interval and required maintaining information about multiple items presented simultaneously. The third pair manipulated the number of sequentially presented items. Analyses of the first two pairs of tasks revealed significant age deficits in working memory for spatial locations but not in working memory for visual features. Notably, there were no age differences in the effect of retention interval on any of the four tasks, suggesting that visuospatial information is lost at similar rates in older and young adults. Analyses of the third pair of tasks revealed that, regardless of domain, increasing the amount of information impaired older adults’ memory performance to a greater extent than young adults’ performance. Thus, the present results suggest differences in basic working memory capacity in both domains, but a lack of age differences in rates of forgetting from working memory, and greater age-related deficits in the spatial domain than in the object domain. 相似文献
908.
探讨重组人粒细胞集落刺激因子(rhG-CSF)对初诊晚期肿瘤患者化疗后骨髓抑制的合理预防用药时机.采用前瞻性随机方法,筛选首次化疗后出现Ⅲ度~Ⅳ度骨髓抑制的肿瘤患者,以化疗前24h内给予rhG-CSF的为预防治疗组;以化疗前未预防性给药为对照组,采用组间对照法,比较两组化疗后骨髓抑制的发生情况.结果发现两组的骨髓抑制发生率,预防组明显低于对照组,且Ⅲ度以上骨髓抑制发生率也明显降低.首次化疗后出现Ⅲ度~Ⅳ度骨髓抑制的肿瘤患者,下次化疗前24h内预防性给予rhG-CSF,能有效控制肿瘤化疗后骨髓抑制的发生,降低感染的风险,值得推广. 相似文献
909.
炎症性肠病是一种病程长且反复的疾病,它的发病可能与环境、免疫、肠道微生态与基因有关.由于摄入减少、消化吸收不良、丢失增加、能量-蛋白质改变和药物作用等各种原因,炎症性肠病患者不管在急性期还是缓解期常常出现营养不良.然而,营养不良又妨碍炎症性肠病治疗的效果,所以肠内外营养对炎症性肠病的治疗就显得至关重要.本文归纳了肠内外营养治疗的价值及成分改良对治疗价值影响的主要进展,最后在此基础上,为了使得营养治疗更有针对性,本文对炎症性肠病患者的营养遗传学及营养基因组学研究提出了展望. 相似文献
910.
一个伟大的哲学家、思想家逝世之后,对他的观点、思想和学说进行持续性研究在人类思想史不乏先例。但是,像马克思主义哲学这样在世界范围内引起如此广泛、深入而持久的研究却是罕见的。更重要的是,每当出现重大历史事件,每当历史处于转折关头,人们都不由自主地把目光转向马克思,并对马克思主义哲学进行新的研究。当然,我们注意到,在对马克思主义哲学不同维度、不同层 相似文献