d-Serine facilitates the effects of extinction to reduce cocaine-primed reinstatement of drug-seeking behavior

Male Sprague Dawley rats were allowed to self-administer cocaine (0.5 mg/kg) during 90 min sessions for a period of 15 days. On day 16, rats were either held abstinent in their home cage environment or experienced an extinction session in which the active lever had no programmed consequences. Facilitating N-methyl-d-aspartate (NMDA) receptor activity with the coagonist d-serine (100 mg/kg i.p.) before or following the extinction session significantly reduced the subsequent cocaine-primed reinstatement of drug-seeking behavior tested on day 17. d-Serine significantly reduced drug-primed reinstatement only when combined with extinction, and its effectiveness when administered following the training session suggested that an enhancement of consolidation of extinction learning had occurred. In contrast, d-serine treatment did not reduce sucrose-primed reinstatement, indicating that the beneficial effects of this adjunct pharmacotherapy with extinction training were specific to an addictive substance (cocaine) and did not generalize to a natural reward (sucrose).     

Acute systemic fibroblast growth factor-2 enhances long-term memory in developing rats

Recent findings have provided much insight into the mechanisms underlying long-term memory formation, and it is now known that long-term memory depends on the activation of a molecular cascade that culminates with structural changes in the brain. However, little is known about the signals that give rise to or regulate these structural changes. In this article we propose that fibroblast growth factor-2 (FGF2), a mitogen for several cell types, may be one of the molecular signals critically involved in the structural changes underlying long-term memory. If FGF2 is part of the signalling cascade involved in long-term memory, then increasing the activation of FGF2 should facilitate memory. In Experiments 1 and 2, we demonstrated that systemic injection of FGF2 (20 ng/g of body weight) facilitated memory for contextual fear in 16, 19, and 22 day old male Sprague Dawley rats. Experiment 3 demonstrated that the observed facilitation of memory was not due to FGF2 increasing rats’ sensitivity to footshock. These results implicate FGF2 as a possible molecular signal in long-term memory, and further, illustrate a novel means of enhancing memory.     

B2C电子商务中的消费者决策支持系统

B2C电子商务环境下的决策支持系统主要包括专家系统,推荐系统和智能代理系统或者其组合等。其目标是帮助消费者发现和澄清需求,在网络海量的信息环境下发现和比较信息,筛选符合客户需要的产品,或者提供建议。该文回顾了近年来网上决策支持系统的研究进展,并对其在B2C电子商务中的应用前景和研究发展趋势进行了预测与展望     

<Emphasis Type="Italic">Special Topic:</Emphasis> Confucian and Christian Conceptions of Creativity

In this article the concept of God as creativity (rather than as “the Creator”) is explored. Though creativity is a profound mystery to us humans, it is a plausible concept today because of its interconnectedness with the belief that our cosmos is evolutionary: new orders of reality come into being in the course of time. Three modalities of creativity are explored here: the initial coming into being of the universe (the Big Bang); the creativity manifest in evolutionary processes; the human creation of culture. It is suggested that this creativity itself should be thought of as God: God is creativity. Thus God-talk is given a referent that is specifiable in terms of today’s understandings of the world and the human. God remains a profound mystery here, but one with a significant place in our modern understanding of the world and human life. This article includes text and ideas taken from my book, In the beginning…Creativity (Kaufman 2004).     

基于P2P的混合过滤文章推荐系统

研究了在分布式的情况下的混合推荐机制,根据P2P环境下文档线性增长的特点,提出了用户兴趣模板的更新算法。实验表明,基于混合过滤的方法推荐效果要远远好于基于内容过滤或基于协作过滤的方法。     

A class of multidimensional IRT models for testing unidimensionality and clustering items

We illustrate a class of multidimensional item response theory models in which the items are allowed to have different discriminating power and the latent traits are represented through a vector having a discrete distribution. We also show how the hypothesis of unidimensionality may be tested against a specific bidimensional alternative by using a likelihood ratio statistic between two nested models in this class. For this aim, we also derive an asymptotically equivalent Wald test statistic which is faster to compute. Moreover, we propose a hierarchical clustering algorithm which can be used, when the dimensionality of the latent structure is completely unknown, for dividing items into groups referred to different latent traits. The approach is illustrated through a simulation study and an application to a dataset collected within the National Assessment of Educational Progress, 1996. The author would like to thank the Editor, an Associate Editor and three anonymous referees for stimulating comments. I also thank L. Scaccia, F. Pennoni and M. Lupparelli for having done part of the simulations.     

东莨菪碱对大鼠空间参考记忆和工作记忆的不同影响

观察东莨菪碱对空间参考记忆和空间工作记忆的编码、保持和提取过程的作用。应用Morris水迷宫实验测定大鼠的空间参考记忆和空间工作记忆,分别在训练的不同阶段腹腔注射东莨菪碱（1mg/kg）和相同容量的生理盐水,比较各东莨菪碱组和生理盐水组之间游泳潜伏期、路径长度、轨迹和游泳速度的差异。结果发现：与注射生理盐水相比,在训练前和探测实验前注射东莨菪碱的大鼠在探测实验中对目标象限不表现出空间偏爱,说明东莨菪碱干扰参考记忆的信息编码和提取过程;而在训练结束后注射东莨菪碱的大鼠探测实验的结果与生理盐水组相比没有显著差异,说明东莨菪碱对参考记忆的保持过程没有影响。在工作记忆实验中,无论第一次测试前、第一次测试后和第2次测试前注射东莨菪碱,均造成大鼠游泳潜伏期延长,说明东莨菪碱干扰工作记忆的编码、保持和提取过程。研究提示M受体在空间工作记忆和参考记忆中发挥不同作用     

EARLY PARENTING SUPPORT AND INFORMATION: A CONSUMER PERSPECTIVE

The transition to parenthood is a period of both joy and challenge for most parents. There is a recognized need to support parents during this period, yet existing interventions have shown limited evidence of efficacy. This study takes a consumer‐focused approach to examine the needs and preferences of parents both prenatally (n = 77) and postnatally (n = 123) for parenting support. The study used a cross‐sectional design with a purpose‐built online survey. Parents were recruited via online forums, Facebook and parenting blogs, childcare centers, and playgroups. In general, all parents were satisfied with their current levels of both formal and informal support, and about one fourth of parents had accessed a parenting intervention. Parents expressed a moderate level of interest in additional parenting information, and parents expecting their first baby indicated preferences for information about basic baby care needs whereas postnatally, parents expressed more interest in topics around self‐care and behavior management. The implications for developing interventions and engaging families are discussed.     

B2C电子商务中消费者的风险来源及其影响

研究目的是通过考察B2C(Business to Consumer)电子商务中消费者知觉到的风险来源来验证电子商务交易中的虚实界面假设。通过访谈法和问卷法调查了337名被试,探讨了B2C电子商务中消费者认知到的风险来源结构,以及这些风险来源对消费者认知风险的影响。结果表明：消费者在B2C电子商务中的认知风险一部分来源于虚实界面