Local sleep and learning

Human sleep is a global state whose functions remain unclear. During much of sleep, cortical neurons undergo slow oscillations in membrane potential, which appear in electroencephalograms as slow wave activity (SWA) of <4 Hz. The amount of SWA is homeostatically regulated, increasing after wakefulness and returning to baseline during sleep. It has been suggested that SWA homeostasis may reflect synaptic changes underlying a cellular need for sleep. If this were so, inducing local synaptic changes should induce local SWA changes, and these should benefit neural function. Here we show that sleep homeostasis indeed has a local component, which can be triggered by a learning task involving specific brain regions. Furthermore, we show that the local increase in SWA after learning correlates with improved performance of the task after sleep. Thus, sleep homeostasis can be induced on a local level and can benefit performance.     

乡土文学史中的莫言乡土小说

莫言的作品大多是以乡土为背景来描写乡村生活的,应该说莫言小说是新时期乡土小说的代表,因此,将莫言的作品置于中国乡土小说背景中将有利于突显出其在乡土文学史上的独特之处。与写实主义和写意主义乡土作家不同,莫言的乡土小说更多的是以一种平民姿态表达着对于乡土中国苦难的体验乃至认同。     

乡土文学史中的莫言乡土小说

莫言的作品大多是以乡土为背景来描写乡村生活的,应该说莫言小说是新时期乡土小说的代表,因此,将莫言的作品置于中国乡土小说背景中将有利于突显出其在乡土文学史上的独特之处。与写实主义和写意主义乡土作家不同,莫言的乡土小说更多的是以一种平民姿态表达着对于乡土中国苦难的体验乃至认同。     

Reverse replay of behavioural sequences in hippocampal place cells during the awake state

The hippocampus has long been known to be involved in spatial navigational learning in rodents, and in memory for events in rodents, primates and humans. A unifying property of both navigation and event memory is a requirement for dealing with temporally sequenced information. Reactivation of temporally sequenced memories for previous behavioural experiences has been reported in sleep in rats. Here we report that sequential replay occurs in the rat hippocampus during awake periods immediately after spatial experience. This replay has a unique form, in which recent episodes of spatial experience are replayed in a temporally reversed order. This replay is suggestive of a role in the evaluation of event sequences in the manner of reinforcement learning models. We propose that such replay might constitute a general mechanism of learning and memory.     

地方高校图书馆搜集地方特色文献的优势和策略

地方高校图书馆搜集地方特色文献具有资政、存史、励志的作用。其搜集方式主要有订购、呈缴、征集、捐赠等10种。重视口述资料、突出地域特点、加强信息沟通、整合数字化资源和编制目录索引鼍．搜集的途径和方法。     

地方文献与州市本科高校图书馆的特色化建设

地方文献特色化建设内容可以分为物质文化形态的地方文献资源、行为文化形态的地方文献建设和观念文化形态的地方文献理论.地方文献特色化发展的基本思路就是以文化层次结构理论审视地方文献系统,以组织形象设计理论指导地方文献建设,以地方文献的形象展示为落脚点推进学科建设和特色发展;其主要措施就是全面加强图书馆的馆藏资源建设、行为规范建设、文献理论建设和组织形象建设.     

Reduced sleep in Drosophila Shaker mutants

Most of us sleep 7-8 h per night, and if we are deprived of sleep our performance suffers greatly; however, a few do well with just 3-4 h of sleep-a trait that seems to run in families. Determining which genes underlie this phenotype could shed light on the mechanisms and functions of sleep. To do so, we performed mutagenesis in Drosophila melanogaster, because flies also sleep for many hours and, when sleep deprived, show sleep rebound and performance impairments. By screening 9,000 mutant lines, we found minisleep (mns), a line that sleeps for one-third of the wild-type amount. We show that mns flies perform normally in a number of tasks, have preserved sleep homeostasis, but are not impaired by sleep deprivation. We then show that mns flies carry a point mutation in a conserved domain of the Shaker gene. Moreover, after crossing out genetic modifiers accumulated over many generations, other Shaker alleles also become short sleepers and fail to complement the mns phenotype. Finally, we show that short-sleeping Shaker flies have a reduced lifespan. Shaker, which encodes a voltage-dependent potassium channel controlling membrane repolarization and transmitter release, may thus regulate sleep need or efficiency.     

基于局部对比度的局部直方图均衡算法

为了更好地增强图像,提出一种新的图像增强方法。首先,将图像分为若干子块,计算每个子块的对比度,根据子块的对比度确定局部点的密度,进而确定子块的个数,然后采用保持亮度的双直方图均衡算法对这些子图进行增强,最后融合各个子图得到最终增强的结果。实验测试结果表明,本算法能够保持均值亮度,提高处理速度,在减少过增强的基础上,增强局部细节,增强后的图像具有良好的视觉效果。     

颗粒物质中的微扰

介绍了容器中颗粒物质内部受到局域微绕的研究进展,并对微扰态的性质和规律做一些分析和讨论。     

局部对称空间中的子流形

讨论局部对称空间中具有平行平均曲率向量的子流形,得到其关于第二基本形式模长平方的积分不等式的相关定理.     

积极发挥地方文献在当地社会发展中的作用

在解释地方文献概念的基础上,介绍了地方文献的特点,分析了地方文献在社会发展中的作用及存在的问题,探讨了积极发挥地方文献作用的途径。     

朱现地保护研究

朱（Ｎｉｐｐｏｎｉａｎｉｐｐｏｎ）是当今世界著名濒危鸟类，从１９８１年重新发现以来，围绕保护工作，开展了广泛的研究．本文综述了保护研究的现状，指出了其中存在的一些问题，并论述了今后的研究重点，为研究保护工作提供依据．     

“以人为本”的服务理念在地方图书馆的实践与思考

“以人为本”的公共文化服务理念,在图书馆事业建设与发展中早已深入人心。受历史惯性和制度设计的影响,重精英、轻贫民,重收藏、轻利用等积习在地方图书馆中依然突出,严重妨碍了图书馆事业的发展。因此,“以人为本”的图书馆理论体系及其在地方图书馆的实践,具有十分重大的现实意义。     

我国地方性公共产品偏好显示与传递机制研究

发达地区地方政府开始关注如何提供居民满意的公共产品,但地方性公共产品偏好显示目前存在一定的困难,现就此作一简单探讨,并提出完善居民对地方性公共产品偏好的显示与传递机制的几点建设:(1)加强人民代表大会的主渠道作用来显示与传递居民偏好;(2)培育非政府组织,增加居民偏好显示与传递途径;(3)降低媒体、信访等渠道的呼吁成本;(4)改革户籍制度,逐步扩展非户籍人口对公共产品的分享;(5)完善省以下分税制,多样化提供公共产品。     

Artin局部环的正则性

文[1]提出了非Artin的Noether局部环是正则环的一个判别方法,并提出该结论对Artin环是否成立的问题。该文讨论了Artin局部环的正则性,并且解决了[1]中提出的问题。     

非线性局部碰磨转子的局部分岔分析

本文考虑了两自由度的非线性局部碰磨转子系统,在原系统的无量纲模型的基础上,用Lyapunov-Flo-quet变换这一解析方法得到便于研究其分岔行为的形式,并用高维分岔理论研究系统的局部分岔行为。     

地方动态

广东:召开全省科学技术大会9月26日,广东省科学技术大会在广州隆重召开。会议总结了近年来广东省科学技术工作,进一步推动广东省与科技部、教育部的产学研合作,加快实施自主创新战略,