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21.
The role of arginine vasopressin (AVP) in the nongenomic transfer of paternal behavior from fathers to offspring was examined in Peromyscus. Male California mice (P. californicus) exposed to fewer retrievals by white-footed mouse (P. leucopus) foster parents displayed fewer retrievals of biological offspring. In contrast, white-footed mice were retrieved equally rarely by California mouse foster parents and by biological parents and displayed no changes in pup retrieval behavior. AVP-immunoreactive staining in the bed nucleus of the stria terminalis may predict paternal behavior because it correlated positively with retrievals and with a score consisting of huddling, grooming, and time inside the nest. The authors discuss AVP as a possible mechanism by which early experience shapes adult paternal behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
The State of the Art in Text Filtering 总被引:1,自引:0,他引:1
This paper develops a conceptual framework for text filtering practice and research, and reviews present practice in the field.
Text filtering is an information seeking process in which documents are selected from a dynamic text stream to satisfy a relatively
stable and specific information need. A model of the information seeking process is introduced and specialized to define text
filtering. The historical development of text filtering is then reviewed and case studies of recent work are used to highlight
important design characteristics of modern text filtering systems. User modeling techniques drawn from information retrieval,
recommender systems, machine learning and other fields are described. The paper concludes with observations on the present
state of the art and implications for future research on text filtering.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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24.
Document image analysis: A primer 总被引:1,自引:0,他引:1
25.
ARMA噪声中的正弦波检测 总被引:2,自引:1,他引:1
本文提出一种ARMA噪声中正弦波检测的方法,本方法先用改进的Prony法估计可能存在的正弦波,然后利用一种综合考虑衰减因子以及MUSIC值的准则从估计结果中区分正统率波的真伪。数值例子表明,本文方法比Prong方法及MUSIC方法具有更高的分辨力。 相似文献
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Before 12 months of age, infants have difficulties coordinating and sequencing their movements to retrieve an object concealed in a box. This study examined (a) whether young infants can discover effective retrieval solutions and consolidate movement coordination earlier if exposed regularly to such a task and (b) whether different environments, indexed by box transparency, would impact the rate of learning and time of discovery of these solutions. Infants (N=12) were presented with an object retrieval task every week from 6 1/2 months of age until they were able to retrieve the toy from the box using coordinated two-handed patterns for 3 weeks. To reach that criterion, infants tested with an opaque box took 2 1/2 months and infants tested with a semitransparent box took 1 1/2 months. Both groups outperformed age-matched controls who received a one-time exposure to the task. Repeated exposure to the task and vision of the toy significantly enhanced this process of solution discovery. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
28.
Wolfgang Appelt 《Computer Standards & Interfaces》1988,7(4):377-385
The Office Document Architecture (ODA) is an International Standard which is developed by TC 97/sc 18 of the International Organization for Standardization (ISO) in close collaboration with CCITT's Study Group VIII and with ECMA. This paper describes the current state of a formal specification of the ODA document structures by mathematical means and its use for conformance specification and conformance testing. 相似文献
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In a change detection paradigm, a target object in a natural scene either rotated in depth, was replaced by another object token, or remained the same. Change detection performance was reliably higher when a target postcue allowed participants to restrict retrieval and comparison processes to the target object (Experiment 1). Change detection performance remained excellent when the target object was not attended at change (Experiment 2) and when a concurrent verbal working memory load minimized the possibility of verbal encoding. (Experiment 3). Together, these data demonstrate that visual representations accumulate in memory from attended objects as the eyes and attention are oriented within a scene and that change blindness derives, at least in part, from retrieval and comparison failure. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献