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991.
The dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) replicates many of the pathological hallmarks of Parkinson's disease (PD) in mice via selective destruction of dopamine neurons of the substantia nigra and striatum. Although MPTP has been widely used to study downstream effects following the degeneration of dopaminergic neurons, the underlying mechanisms of MPTP action remain poorly understood. To determine the underlying mechanisms of MPTP action at the protein level, a 2-DE-based proteomics approach was used to evaluate the changes in protein expression in substantia nigra and striatal tissue in C57BL/6 mice after MPTP administration. We identified nine proteins that were markedly altered and are likely to be involved in mitochondrial function, heat shock protein activity, and which contribute enzyme activities for energy metabolism and protein degradation. 相似文献
992.
Bruno Juliá-Díaz Joseph M. Burdis Frank Tabakin 《Computer Physics Communications》2006,174(11):914-934
This Mathematica 5.2 package1 is a simulation of a Quantum Computer. The program provides a modular, instructive approach for generating the basic elements that make up a quantum circuit. The main emphasis is on using the density matrix, although an approach using state vectors is also implemented in the package. The package commands are defined in Qdensity.m which contains the tools needed in quantum circuits, e.g., multiqubit kets, projectors, gates, etc. Selected examples of the basic commands are presented here and a tutorial notebook, Tutorial.nb is provided with the package (available on our website) that serves as a full guide to the package. Finally, application is made to a variety of relevant cases, including Teleportation, Quantum Fourier transform, Grover's search and Shor's algorithm, in separate notebooks: QFT.nb, Teleportation.nb, Grover.nb and Shor.nb where each algorithm is explained in detail. Finally, two examples of the construction and manipulation of cluster states, which are part of “one way computing” ideas, are included as an additional tool in the notebook Cluster.nb. A Mathematica palette containing most commands in QDENSITY is also included: QDENSpalette.nb.
Program summary
Title of program: QDENSITYCatalogue identifier: ADXH_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADXH_v1_0Program available from: CPC Program Library, Queen's University of Belfast, N. IrelandOperating systems: Any which supports Mathematica; tested under Microsoft Windows XP, Macintosh OS X, and Linux FC4Programming language used: Mathematica 5.2No. of bytes in distributed program, including test data, etc.: 180 581No. of lines in distributed program, including test data, etc.: 19 382Distribution format: tar.gzMethod of solution: A Mathematica package is provided which contains commands to create and analyze quantum circuits. Several Mathematica notebooks containing relevant examples: Teleportation, Shor's Algorithm and Grover's search are explained in detail. A tutorial, Tutorial.nb is also enclosed. 相似文献993.
Making decisions can be hard, but it can also be facilitated. Simple heuristics are fast and frugal but nevertheless fairly accurate decision rules that people can use to compensate for their limitations in computational capacity, time, and knowledge when they make decisions [Gigerenzer, G., Todd, P. M., & the ABC Research Group (1999). Simple Heuristics That Make Us Smart. New York: Oxford University Press.]. These heuristics are effective to the extent that they can exploit the structure of information in the environment in which they operate. Specifically, they require knowledge about the predictive value of probabilistic cues. However, it is often difficult to keep track of all the available cues in the environment and how they relate to any relevant criterion. This problem becomes even more critical if compound cues are considered. We submit that knowledge about the causal structure of the environment helps decision makers focus on a manageable subset of cues, thus effectively reducing the potential computational complexity inherent in even relatively simple decision-making tasks. We review experimental evidence that tested this hypothesis and report the results of a simulation study. We conclude that causal knowledge can act as a meta-cue for identifying highly valid cues, either individual or compound, and helps in the estimation of their validities. 相似文献
994.
面向企业的运输销售管理信息系统设计 总被引:3,自引:0,他引:3
以石油企业运输销售经营管理为背景,对运输销售管理信息系统进行了研究.以软件工程为指导,运用先进的设计方法与结构分析,并结合数据库的特点给出了运输销售管理信息系统具体的设计方案. 相似文献
995.
WIN9X环境下驱动程序的实现 总被引:1,自引:0,他引:1
本简述了DLL(动态链接库)和VXD(虚拟设备驱动程序)的区别,通过实例,介绍了这两种方法在同一控制系统中的实现。 相似文献
996.
介绍了WebSphere应用服务器的基本特性,详细地论述了WebSphrer应用服务器的安装,配置和使用方法。 相似文献
997.
998.
1995~ 1 996年进行的田间和盆栽试验表明 ,硫氮或硫硼配施可以显著增加菜籽产量 .硫氮配施比对照增产 1 0 8 2~ 3 1 4 0kg/hm2 和 5 5~ 1 9 6% ,硫硼配施比对照增产 83 4~ 2 4 8 2kg/hm2 和 6 9~2 3 1 % .施硫可以增加油菜植株体内的硫含量并改善其硫素营养 ;在缺硫土壤上施硫可以降低菜籽硫甙及芥酸含量 ,提高油酸含量 ,因此有改善菜籽品质的作用 . 相似文献
999.
以logistic模型为基础 ,以时间因子为媒介 ,推导出一个能准确描述植物病害I-S的logistic衍生模型。通过对油松落针病、花生锈病、烟草黄瓜花叶病和小麦赤霉病等多组I-S关系数据的实例验证与比较分析 ,显示出这一模型具有较强的数据拟合能力和广泛的适用性。Logistic衍生模型尚可应用于林木胸径与材积(D -V)关系、径与树高(D -H)关系以及生物量预估等项研究。此外 ,还提出一个具有普遍指导意义的通用模型 相似文献
1000.
根际环境因子对马铃薯块茎生长发育具有重要影响。马铃薯根际环境因子包括光照、温度、水分、空气、营养以及重力等,从生态学的角度综述了根际环境因子对马铃薯块茎生长发育的影响,并对存在的问题及其研究进展进行了讨论。 相似文献