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61.
Although dopamine is necessary for mammalian adult pair-bond formation and maternal behavior, its function in infant social behavior and attachment has been less thoroughly explored. The vocalization rate of an isolated rat pup is influenced by recent social contact. Interactions with the dam potentiate vocalization rate. Interactions with littermates or adult males do not. Systemic administration of the D2-family agonist quinpirole specifically blocked maternal potentiation at doses that did not alter vocalization rate in an isolation prior to dam contact. This result was not explained by quinpirole's effects on body temperature or locomotion. The results are consistent with a role for dopamine in infant social behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
62.
Research has demonstrated that oral reading fluency probes are reliable and valid for indexing reading achievement. If these probes are to be used for decision making, bias must be examined for various factors, including ethnicity, gender, language background, and socioeconomic status. Data from nearly 4,000 Caucasian and Hispanic students in grades one through three were used to examine potential bias in oral reading fluency scores predicting Stanford Achievement Test-Ninth Edition (SAT-9; Harcourt Brace & Co., 1997a, 1997b) Total Reading scores. Using a series of hierarchical multiple regression models, bias was first examined using concurrent SAT-9 scores as the criterion and then examined using subsequent SAT-9 scores as the criterion. The results reveal that it is the combination of factors, not any one in isolation, that significantly contributes to intercept bias findings. Overall, home language emerged as the strongest factor influencing bias in the prediction of SAT-9 scores from oral reading fluency scores. The implications of these findings are discussed as related to current and proposed uses of oral reading fluency probes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
63.
On the basis of the terror management theory proposition that self-esteem provides protection against concerns about mortality, it was hypothesized that self-esteem would reduce the worldview defense produced by mortality salience (MS). The results of Exps 1 (49 undergraduates) and 2 (50 undergraduates) confirmed this hypothesis by showing that individuals with high self-esteem (manipulated in Exp 1; dispositional in Exp 2) did not respond to MS with increased worldview defense, whereas individuals with moderate self-esteem did. The results of Exp 3 (48 undergraduates) suggested that the effects of the 1st 2 experiments may have occurred because high self-esteem facilitates the suppression of death constructs following MS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
64.
The authors hypothesized, on the basis of terror management theory and cognitive-experiential self-theory, that participants in an experiential mode of thinking would respond to mortality salience with increased worldview defense and increased accessibility of death-related thoughts, whereas participants in a rational mode would not. Results from 3 studies provided convergent evidence that when participants were in an experiential mode, mortality salience produced the typical worldview defense effect, but when participants were in a rational mode it did not. Study 4 revealed that mortality salience also led to a delayed increase in the accessibility of death-related thoughts only when participants were in an experiential mode. These results supported the notion that worldview defense is intensified only if individuals are in an experiential mode when considering their mortality. Discussion focuses on implications for understanding terror management processes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
65.
R. Brown  Jeff W. Edington 《Wear》1981,69(3):369-382
High purity copper single crystals were eroded parallel to [111] at 90° to the surface with glass spheres 70 μm in diameter travelling at a velocity of 122 m s?1. Detailed scanning electron microscopy of eroded surfaces together with transmission electron microscopy of both erosion debris and near-surface layers of the target was performed. It was observed that a hilland-valley surface topology developed ; this has not been reported previously and gave rise to a local low angle cutting component of erosion at 90°. Direct evidence was obtained of a transient heating effect from the particle impact as well as the formation of subsurface voids in heavily deformed regions. In addition it was shown that subsurface cracking produced a flaking mechanism of material loss.  相似文献   
66.
R. Brown  Jeff W. Edington 《Wear》1982,79(3):335-346
High purity copper single crystals were eroded at 30° to a (111) face using glass spheres 210 μm in diameter travelling at a velocity of 133 m s?1. Detailed scanning electron microscopy of both eroded surfaces and metallographic sections has been performed together with transmission electron microscopy of erosion debris. It was observed that there was extensive surface shear that led to ripple formation, folding of the surface, subsurface crack propagation and material loss by flaking similar to delamination wear. Direct evidence was obtained for recrystallization of the surface layers.  相似文献   
67.
量测平台的复杂性和光学原理上的局限性制约着测量系统的应用,直到真空紫外光谱反射仪的出现,这种状况才得到改变。  相似文献   
68.
引言 把语音服务、高分辨率相机模块、MP3或PMP播放器功能整合在单个移动电话设计中,已成为未来中高端电话市场的发展趋势。除了超高的功率(〉700mW)立体声音频功能外,视频输出功能也出现在手机应用中,其输出仍主要是CVBS格式,而某些电话甚至提供S视频或模拟RGB输出。  相似文献   
69.
ZnO is a highly efficient photon emitter, and has optical and piezoelectric properties that are attractive for a variety of applications in sensors and potentially optoelectronic devices such as emitters. Due to its identical stacking order and close lattice match to GaN, it is also being developed as a substrate material for GaN epitaxy. However, the surface finish of the ZnO is such that much of the damage induced by sawing and follow up mechanical polishing remains. We developed a thermal treatment method to eliminate surface damage on the 0 face of ZnO (0 0 0 1) to prepare it for epitaxial growth. Atomic force microscopy images of ZnO (0 0 0 1) annealed at 1050 °C for 3 h etc. show that residual scratches from mechanical polishing are removed and atomically flat, terrace-like surfaces are attained. In addition, low-temperature photoluminescence and high-resolution X-ray diffraction measurements have been employed to investigate the effect of annealing on ZnO substrates.  相似文献   
70.
The Automated Metadata Indexing and Analysis (AMIA) project aims to provide an effective digital asset management (DAM) tool for large digital asset databases. We began with text-based indexing since it is still the most reliable approach as compared with other content-based media features. AMIA not only searches for the text of the file name, but also utilizes embedded information such as the metadata in Maya files. The AMIA system builds a linked map between all dependency files. We present an approach of preserving previously established metadata created by the old DAM tools, such as AlienBrain, and integrating them into the new system. Findings indicate that AMIA has significantly improved search performance comparing to previous DAM tools. Finally, the ongoing and future work in the AMIA project is described.  相似文献   
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