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1.
Seventy-nine 3-year olds and their mothers participated in a laboratory-based task to assess maternal hostility. Mothers also reported their behavioral regulation of their child. Seven years later, functional magnetic resonance imaging data were acquired while viewing emotional faces and completing a reward processing task. Maternal hostility predicted more negative amygdala connectivity during exposure to sad relative to neutral faces with frontal and parietal regions as well as more negative left ventral striatal connectivity during monetary gain relative to loss feedback with the right posterior orbital frontal cortex and right inferior frontal gyrus. In contrast, maternal regulation predicted enhanced cingulo-frontal connectivity during monetary gain relative to loss feedback. Results suggest parenting is associated with alterations in emotion and reward processing circuitry 7–8 years later.  相似文献   
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健康作为一种人力资本投资对提高生产力、促进经济发展和个人发展有着重要的作用。它可以提高劳动者的生产效率,刺激教育方面的投资,使人具有更多的时间和能力利用其他资本要素,具有更大的财力(因减少医疗费用)用于其他方面的投资。所以进行人力资本投资时,不可忽视健康这一要素,它也是人力资本形成的重要途径,也对经济增长起着有力的推动作用。  相似文献   
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The goal of the Standards for Educational and Psychological Testing is to improve testing practices, but their impact on practice appears spotty. Self-regulation clearly fails in some instances. The establishment of an external agency to oversee testing practices and adherence to the Standards would face substantial hurdles, and the ambiguity of many of the Standards would hobble such an organization if one were created. Many of the Standards are general statements of principle, and past controversies make clear that we in the field often disagree about the reasons for them, their applicability to specific cases, and their practical meaning in specific contexts. This paper argues that the field should follow two approaches to lessen this ambiguity. First, using journals, conferences, and other vehicles, we should foster more frequent and more protracted debate about the practical meaning of key Standards, such as 13.6 and 13.7, which mandate that a decision that will have a "major impact" on a student should not be based on a single score. Second, future revisions of the Standards should use concrete examples of testing practices to clarify the meaning of the Standards, much as the legal system uses case law to clarify the meaning of the general principles embodied in statutes .  相似文献   
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Book reviews     
cAbd al‐Malik b. Habib. Kitāb al‐Ta'rij (La historia). Edición y estudio por Jorge Aguadé. Madrid: Consejo Superior de Investigaciones Científicas & Instituto de Cooperación con el Mundo Arabe, 1991 (Fuentes Arabico‐Hispanas, 1). 163 + 224 pp. [Arabic title: Kltāb al‐Ta'tikh]

Kedar, Benjamin Z., ed. The Horns of Hattin. Jerusalem and London: Yad Izhak Ben‐Zvi, Israel Exploration Society and Variorum 1992. 368 pp., 12 plates; $74.75 (cloth).

Köprülü, Mehmed Fuad. The Seljuks of Anatolia: Their History and Culture According to Local Muslim Sources. Translated and edited by Gary Leiser. Salt Lake City: University of Utah, 1992. xi +101 pp., $22.00 (cloth).

Cameron, Averil and Conrad, Lawrence I., eds. The Byzantine and Early Islamic Near East: Problems in the Literary Source Material (Papers in the First Workshop on Late Antiquity and Early Islam). Princeton: The Darwin Press, 1992. xiv + 428pp., 12 plates; $29.25 (cloth).

Vereno, Ingolf. Studien zum ältesten alchemistischen Schrifttum. Berlin: Klaus Schwarz Verlag, 1992 (Islamkundliche Untersuchungen, 155). 414pp.

Tolan, John. Petrus Alfonsi and his Medieval Readers. Gainesville, Florida: University Press of Florida, 1993. xv + 288pp., $34.95 (cloth), $16.95 (paper).

Lassner, Jacob. Demonizing the Queen of Sheba: Boundaries of Gender and Culture in Postbiblical Judaism and Medieval Islam. Chicago: University of Chicago, 1994. 281 pp., $19.95 (paper), $49.95 (cloth).

Menocal, María Rosa. Shards of Love: Exile and the Origins of the Lyric. Durham, North Carolina: Duke University Press, 1994. xv + 295pp., $34.95 (cloth), $14.95 (paper).

Massignon, Louis. The Passion of al‐Hallāj, Mystic and Martyr of Islam. Translated and edited by Herbert Mason. Abridged edition, Bollingen Series XCVIII. Princeton: Princeton University Press, 1994. xxxi + 293pp.

Viguera Molins, Maria Jesús. El Islam en Aragón. Saragossa: Caja de Ahorros de la Inmaculada, 1995 (Colección “Mariano de Pano y Ruata”, 9), 174 pp., 182 ills. in colour, maps, diagrams, charts etc No price stated.  相似文献   

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Millions of Canadians residing in Canada's northern, isolated, rural, and remote communities do not have broadband Internet access. This situation has led to a national “broadband divide.” That is, the deployment of wireline broadband is very limited in Canada's northern, isolated, rural, and remote areas because of the significant expense of installation and maintenance of the wired infrastructure needed to reach dwellings in these locations.Terrestrial broadband wireless technology, on the other hand, does not entail the same kind of physical infrastructure. As a result, there are dramatic changes in how spatial considerations affect the provision of broadband Internet services (BIS) to areas beyond the urban zone. In particular, the spatial question is now focused on assessing the capacity for different technological solutions to reach profitable population bases, and brings to the forefront organizations that are developing non-line-of-sight (NLOS) technologies that would permit wireless Internet access over much greater distances than current solutions.We begin this paper by establishing the importance of broadband connectivity to Canada's northern, isolated, rural, and remote communities. This discussion comments on the role of the Government of Canada in the provision of broadband connectivity to residents of these communities, and outlines the current regulatory issues that govern wireless services and policy formulation.The second part of the paper illustrates the use of geographic information system (GIS) approaches in the study of wireless broadband planning and deployment. Case study findings suggest that GIS applications can make a significant contribution to the analysis of wireless deployment planning, to the understanding of the relationships between wireless signal sources and consumers, and to the spatial configuration of terrestrial wireless broadband networks. We conclude the paper by discussing how the GIS approach employed could be used to inform the public policy process with regard to increasing access to broadband Internet services in all regions of the country, and thereby providing the opportunity for all Canadians, regardless of location, to fully participate in the Information Society.  相似文献   
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In 2001, the Regenstrief Institute for Health Care and the Indiana University School of Medicine (IUSM) began an IAIMS planning effort to create a vision and a tactical plan for the first Integrated Advanced Information Management Systems (IAIMS) implementation to cross a large area and include unaffiliated institutions. A number of elements made this planning effort unique. Among these elements were the existence of a network infrastructure that supported the Indianapolis Network for Patient Care, the existence of a mature medical informatics program at the Regenstrief Institute, and the existence of a wide-area knowledge network fostered by the IUSM libraries. However, the leadership for a strong information technology role in the IUSM that could promote collaboration in support of education and research across the diverse Indianapolis hospital systems had been lacking. By bringing together various groups, each with a commitment to improve health care quality and public health across the Indianapolis metropolitan area, regardless of individual institutional affiliation, the strategic directions for I3-Indianapolis IAIMS Initiative have been defined and the foundations for a third generation IAIMS construct have been laid in Indianapolis, Indiana.  相似文献   
10.
Scale and Translation Invariant Collaborative Filtering Systems   总被引:1,自引:0,他引:1  
Collaborative filtering systems are prediction algorithms over sparse data sets of user preferences. We modify a wide range of state-of-the-art collaborative filtering systems to make them scale and translation invariant and generally improve their accuracy without increasing their computational cost. Using the EachMovie and the Jester data sets, we show that learning-free constant time scale and translation invariant schemes outperforms other learning-free constant time schemes by at least 3% and perform as well as expensive memory-based schemes (within 4%). Over the Jester data set, we show that a scale and translation invariant Eigentaste algorithm outperforms Eigentaste 2.0 by 20%. These results suggest that scale and translation invariance is a desirable property.  相似文献   
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