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281.
Plain Semi-Post algebras as a poset-based generalization of post algebras and their representability
Semi-Post algebras of any type T being a poset have been introduced and investigated in [CR87a], [CR87b]. Plain Semi-Post algebras are in this paper singled out among semi-Post algebras because of their simplicity, greatest similarity with Post algebras as well as their importance in logics for approximation reasoning ([Ra87a], [Ra87b], [RaEp87]). They are pseudo-Boolean algebras generated in a sense by corresponding Boolean algebras and a poset T. Every element has a unique descending representation by means of elements in a corresponding Boolean algebra and primitive Post constants which form a poset T. An axiomatization and another characterization, subalgebras, homomorphisms, congruences determined by special filters and a representability theory of these algebras, connected with that for Boolean algebras, are the subject of this paper.To the memory of Jerzy SupeckiResearch reported here has been supported by Polish Government Grant CPBP 01.01 相似文献
282.
Andrew B. Watson Kenneth R. K. Nielsen Allen Poirson Andrew Fitzhugh Amy Jo Bilson Khanh Nguyen Albert J. Ahumada 《Behavior research methods》1986,18(6):587-594
For the study of human and animal vision, the video framebuffer is the only technology that is capable of displaying two-dimensional images with precise control of contrast, luminance, and display timing. The video framebuffer also allows precise control of color. However, this device is not designed for precise psychophysical displays, and techniques must be developed to use them in this role. In this paper, we describe a number of basic methods used in our lab. In order to be concrete, we use an Adage RDS-3000 raster display system (Adage, 1982) as an example, since that is the device we have actually used. The Adage is hosted by a PDP-11/73 under the Venix operating system. The principles generalize to other machines. Where it clarifies the issues, we have shown the syntax of the software routines involved. 相似文献
283.
α7 Nicotinic Receptor Subunits Are Not Necessary for Hippocampal-Dependent Learning or Sensorimotor Gating: A Behavioral Characterization of Acra7-Deficient Mice
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Richard Paylor Michelle Nguyen Jacqueline N. Crawley James Patrick Arthur Beaudet Avi Orr-Urtreger 《Learning & memory (Cold Spring Harbor, N.Y.)》1998,5(4):302-316
The α7 nicotinic acetylcholine receptor (nAChR) subunit is abundantly expressed in the hippocampus and contributes to hippocampal cholinergic synaptic transmission suggesting that it may contribute to learning and memory. There is also evidence for an association between levels of α7 nAChR and in sensorimotor gating impairments. To examine the role of α7 nAChRs in learning and memory and sensorimotor gating, Acra7 homozygous mutant mice and their wild-type littermates were tested in a Pavlovian conditioned fear test, for spatial learning in the Morris water task, and in the prepulse inhibition paradigm. Exploratory activity, motor coordination, and startle habituation were also evaluated. Acra7 mutant mice displayed the same levels of contextual and auditory-cue condition fear as wild-type mice. Similarly, there were no differences in spatial learning performance between mutant and wild-type mice. Finally, Acra7 mutant and wild-type mice displayed similar levels of prepulse inhibition. Other behavioral responses in Acra7 mutant mice were also normal, except for an anxiety-related behavior in the open-field test. The results of this study show that the absence of α7 nAChRs has little impact on normal, base-line behavioral responses. Future studies will examine the contribution of α7 nAChR to the enhancement of learning and sensorimotor gating following nicotine treatments. 相似文献
284.
一种新的等值准则及其适用范围的探讨 总被引:3,自引:0,他引:3
受假设检验方法的启发,该文引出了一种基于项目反应理论的新等值方法——平方根等值准则。它具有一些特点:定义式中答对、答错概率同时出现而不能互相替代;极易从0—1评分模式的版本转换到多级评分版本;它可以看成是Haebara等值准则的加权形式。以等值系数估计值的误差大小为衡量标准,以Wilcoxon符号秩检验为依据,大量的Monte Carlo模拟结果显示了一种有趣的现象,即等值方法的运用范围既与项目参数估计精度有关,又与等值系数A的范围有关,但与另一个等值系数B的范围无关。当项目参数估计精度较高或中等而A取值在0.9~1.3之间,新方法往往比Stocking_Lord方法和Haebara方法的估计误差小且有显著性差异,当项目参数估计精度较低时,而A从1.0~2.0时新方法都有优越性。 相似文献
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287.
社会主义核心价值的基本内容包括富强、民主、文明、和谐、无神论思想包含在这些内容之中并起到重要作用。国强民富离不开科学技术,无神论是科学技术的理论前提和方法论起点;民主而不是神主。以人为本而不是以神为本,是无神论思想的根本体现;无神论是最初的也是最基本的文明成果;一个无神论基础上的社会和谐是真实而长久的和谐。 相似文献
288.
Previous findings suggest that the rostral anterior cingulate cortex (rACC) is involved in memory for emotionally arousing training. There is also extensive evidence that the basolateral amygdala (BLA) modulates the consolidation of emotional arousing training experiences via interactions with other brain regions. The present experiments examined the effects of posttraining intra-rACC infusions of the cholinergic agonist oxotremorine (OXO) on inhibitory avoidance (IA) retention and investigated whether the BLA and rACC interact in enabling OXO effects on memory. In the first experiment, male Sprague-Dawley rats were implanted with bilateral cannulae above the rACC and given immediate posttraining OXO infusions. OXO (0.5 or 3 ng) induced significant enhancement of retention performance on a 48-h test. In the second experiment, unilateral posttraining OXO infusions (0.5, 3.0 or 10 ng) enhanced retention when infused into rACC, but not caudal ACC, consistent with previous evidence that ACC is composed of functionally distinct regions. A third experiment investigated the effects of posttraining intra-rACC OXO infusions (0.5 or 10 ng) in rats with bilateral sham or NMDA-induced lesions of the BLA. The BLA lesions did not impair IA retention, but blocked the enhancement induced by posttraining intra-rACC OXO infusions. Lastly, unilateral NMDA lesions of rACC blocked the enhancement of IA retention induced by posttraining ipsilateral OXO infusions into the BLA. These findings support the hypothesis that the rACC is involved in modulating the storage of emotional events and provide additional evidence that the BLA modulates memory consolidation through interactions with efferent brain regions, including the cortex. 相似文献
289.
父母冲突、青少年的认知评价及其与青少年社会适应的关系 总被引:1,自引:0,他引:1
以446名小学五年级至初中二年级的学生为被试,采用问卷法,让被试报告父母冲突形式、内容,对父母冲突的认知评价,以及抑郁、焦虑、自尊、学习问题和不良行为,以探讨父母冲突形式和内容、青少年对冲突的评价与其社会适应的关系,并检验认知评价在父母冲突与青少年适应间的中介作用。结果发现:(1)男女生除在父母情绪冲突和自尊方面的报告有显著差异外,其余各个方面都没有显著差异;随年级升高,儿童知觉的父母冲突内容显著增多,抑郁情绪、学习问题显著增多,而自尊水平显著下降;(2)父母冲突的不同形式和内容,以及青少年对父母冲突的不同认知评价可以预测青少年不同方面的社会适应;(3)认知评价在父母冲突与青少年的内部适应中起中介作用,但在父母冲突与青少年的外部适应中不起中介作用。 相似文献
290.
本文对具有较好发展前景的HO-DINA模型进行拓展,将仅适用于0-1评分题型的HO-DINA模型拓广至可用于多级评分题型,采用MCMC算法实现了对模型参数的估计,并对新模型性能进行了研究。研究发现: (1)本文拓展的多级评分HO-DINA模型参数估计精度较高且诊断正确率较高。(2)多级评分的HO-DINA模型诊断的属性个数越多,属性参数( 和 )和s参数估计的精度越差、属性诊断的正确率(MMR和PRM)越低,但能力参数( )和g参数的估计精度反而越高。(3)在当前条件下,若想保证属性模式判准率在80%以上,建议诊断的属性个数不宜超过7个。 相似文献