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11.
DNA double-strand breaks (DSBs), classified as the most harmful type of DNA damage based on the complexity of repair, lead to apoptosis or tumorigenesis. In aging, DNA damage increases and DNA repair decreases. This is exacerbated in disease, as post-mortem tissue from patients diagnosed with mild cognitive impairment (MCI) or Alzheimer’s disease (AD) show increased DSBs. A novel role for DSBs in immediate early gene (IEG) expression, learning, and memory has been suggested. Inducing neuronal activity leads to increases in DSBs and upregulation of IEGs, while increasing DSBs and inhibiting DSB repair impairs long-term memory and alters IEG expression. Consistent with this pattern, mice carrying dominant AD mutations have increased baseline DSBs, and impaired DSB repair is observed. These data suggest an adaptive role for DSBs in the central nervous system and dysregulation of DSBs and/or repair might drive age-related cognitive decline (ACD), MCI, and AD. In this review, we discuss the adaptive role of DSBs in hippocampus-dependent learning, memory, and IEG expression. We summarize IEGs, the history of DSBs, and DSBs in synaptic plasticity, aging, and AD. DSBs likely have adaptive functions in the brain, and even subtle alterations in their formation and repair could alter IEGs, learning, and memory.  相似文献   
12.
概述了炼钢—连铸—热轧一体化生产管理系统的设计方案,采用软件工程方法开发炼钢计划与实绩管理子系统,简要介绍了子系统功能构成及动态调整设计.实验室模拟运行效果良好.  相似文献   
13.
Ordinal knowledge is a fundamental aspect of advanced cognition. It is self-evident that humans represent ordinal knowledge, and over the past 20 years it has become clear that nonhuman primates share this ability. In contrast, evidence that nonprimate species represent ordinal knowledge is missing from the comparative literature. To address this issue, in the present experiment we trained pigeons on three 4-item lists and then tested them with derived lists in which, relative to the training lists, the ordinal position of the items was either maintained or changed. Similar to the findings with human and nonhuman primates, our pigeons performed markedly better on the maintained lists compared to the changed lists, and displayed errors consistent with the view that they used their knowledge of ordinal position to guide responding on the derived lists. These findings demonstrate that the ability to acquire ordinal knowledge is not unique to the primate lineage. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
14.
This research examines the possibility that people's choices in the service of an explicit focal goal may also reflect their tendency to fulfill implicit background goals and in that sense are multifinal. We carried out 5 experimental studies to investigate this notion. In Experiment 1, a primed implicit goal affected individuals' choices even when those avowedly served an explicit “focal” goal. Experiment 2 replicated this finding with a different type of implicit goals. Experiment 3 found that primed implicit goals had no effect on choices where the options that served them undermined the explicit goal. Experiment 4 found that a primed implicit goal served by a multifinal option does not privilege it over a unifinal option if that goal had been already attained by a different means. Finally, Experiment 5, via 3 types of control groups, showed that choices were affected by both the explicit and implicit goals in isolation, and they shifted toward multifinality when these goals were conjointly present. The discussion considers the integrative potential of the multifinality framework and its implications for a variety of phenomena in the domain of motivated cognition. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
15.
Reviews the book, Cognition by John G. Benjafield, et al. (2010). Cognition (4th ed.) provides a comprehensive introduction to cognitive psychology for undergraduate students and others who require an overview of the area. New in the fourth edition is a chapter on cognitive neuroscience. The reviewer only has one criticism of Benjafield et al.: Citations for published works in every chapter that also appeared in the third edition stop around 2007 or earlier (when the third edition was published). Cognition is a book that will appeal to those looking for a high-level, scholarly survey of cognitive psychology. It is this aspect of Cognition that sets it apart from most other textbooks that cover cognitive psychology. Yet, despite its scholarly approach, it remains an engaging text that makes the reader want to keep reading more: a delicate balance, but one that Benjafield et al. manage with aplomb. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
16.
Reports an error in A core knowledge architecture of visual working memory by Justin N. Wood (Journal of Experimental Psychology: Human Perception and Performance, 2011[Apr], Vol 37[2], 357-381). The supplemental materials DOI is incorrect. The correct DOI for the supplemental materials is provided in the erratum. (The following abstract of the original article appeared in record 2011-06411-002.) Visual working memory (VWM) is widely thought to contain specialized buffers for retaining spatial and object information: a 'spatial-object architecture.' However, studies of adults, infants, and nonhuman animals show that visual cognition builds on core knowledge systems that retain more specialized representations: (1) spatiotemporal representations for object tracking, (2) object identity representations for object recognition, and (3) view-dependent snapshots for place recognition. In principle, these core knowledge systems may retain information separately from one another. Consistent with this hypothesis, this study provides evidence that these three types of information are subject to independent working memory storage limits. These results, combined with those from previous studies, indicate that VWM contains three specialized buffers for retaining spatiotemporal information, object identity information, and snapshot information. Thus, VWM buffers parallel core knowledge systems. This 'core knowledge architecture' links the study of visual working memory to the study of the biological foundations of visual cognition. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
17.
Typically developing children understand and predict others' behavior by extracting and processing relevant information such as the logic of their actions within the situational constraints and the intentions conveyed by their gaze direction and emotional expressions. Children with autism have difficulties understanding and predicting others' actions. With the use of eye tracking and behavioral measures, we investigated action understanding mechanisms used by 18 children with autism and a well-matched group of 18 typically developing children. Results showed that children with autism (a) consider situational constraints in order to understand the logic of an agent's action and (b) show typical usage of the agent's emotional expressions to infer his or her intentions. We found (c) subtle atypicalities in the way children with autism respond to an agent's direct gaze and (d) marked impairments in their ability to attend to and interpret referential cues such as a head turn for understanding an agent's intentions. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
18.
基于Kinect体感器开发一套幼儿认知系统,以激发幼儿认知的兴趣,陶冶幼儿的情操,促进幼儿的智力发展,提高幼儿的认知能力。幼儿认知系统是基于Kinect的体感技术,借助Kinect感应系统来定位捕捉幼儿动作及识别幼儿的语音信息,通过Kinect体感设备与计算机系统连接,将动作及语音信息输入系统,实现幼儿与系统之间互动,带幼儿进入模拟真实的认识环境中,沉浸在虚拟现实中进行认知训练,在娱乐中提高幼儿认知能力。  相似文献   
19.
This paper introduces the research progress on the cognition flow in the National Basic Research Program of China (973 Program) under Grant No. 2009CB320400 "Research on Basic Theories and Key Technologies of Cognitive Radio Networks". We present the motivation behind the proposal of the concept of cognition flow, provide the definition, discuss the features, behaviours, representations, math- ematical models, and the functions of cognition flow in Cognitive Radio Networks (CRNs). We also analyse how the cognition flow promotes the convergence of heterogeneous networks. Our group also constructed the test platform to verify the usefulness of cognition flow. The results that were simulated by computers and tested on the platform both confirm that cognition flow can realise efficient interaction of cognitive information among heterogeneous networks in CRNs, which contributes to the seamless convergence of heterogeneous networks, and significantly improves the spectrum efficiency and users' Quality of Experience (QoE).  相似文献   
20.
鉴于目前在水厂的自动控制中,多采用的是用PLC构成的集散式控制系统(Distributed Control System,DCS)。介绍采用现场总线技术(Fieldbus technology)构成全分布式管控一体化网络中前端智能节点的配置与实现。在此,首先介绍底层测控设备的类型与性能参数;进而介绍LonWorks智能节点的组成、性能和开发使用;最后,介绍该控制系统中前端智能节点的配置与实现。  相似文献   
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