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91.
Voting systems have become controversial in the years following the multiple election disasters that occurred in the United States during and after 2000. Of particular note were the electronic voting (e-voting) systems that were widely deployed to replace the pre-scored punch-card systems, systems that had have been frequently judged to be central to the problem in the 2000 Florida general election. The (premature) deployment of e-voting machines stimulated a new field of security and privacy research around the subject of elections, a subject that has turned out to be more complex and deeper than anyone would have predicted a decade ago. Here we present a sample of some of the finest recent work on election technology from authors on three continents.  相似文献   
92.
Extensible Markup Language (XML) and the XML Path Language (XPath) are introduced with software examples demonstrating how one can use them to write laboratory data management programs. Topics explored include XML document creation, manipulation, and searching. Programming examples make use of the Microsoft® XML Parser library and the Visual Basic programming language. The problem of managing microplate screening data is used as an illustration. Source code for all examples can be downloaded from http://www.labprogrammer.net.  相似文献   
93.
利用随机相变动力学理论研究运动认知的神经网络动力学模型.给出了感觉神经元集群、中间神经元集群和运动皮层神经元集群在耦合条件下相互作用、相位编码和数密度随时间的演化.探讨了神经网络在自发运动条件下以及在刺激条件下的神经网络动力学响应.通过数值模拟证实了(1)Walter J.Freeman提出的皮层动力学响应不能够编码外刺激信息的猜想;(2)串行的神经网络系统的神经编码具有节律编码的性质;(3)在中枢神经系统的调控中,神经抑制有其重要的作用.  相似文献   
94.
神经系统的信息处理过程依赖于一种基本的神经机制-相位同步化.已往的研究表明单个神经元的spike与LFP构成同步化时会对应一个精确的相位,该相位能够对进一步处理信息以及与时间相关的可塑性产生影响.本文基于这项研究,提出了一种新颖的研究同步化现象的方法.运用该方法探索局部场电位(LFP)与神经元动作电位发放(Spikes)之间的相关性,该方法不仅能够保证数据分析的可靠性,而且在使用方面更简单、更具普遍性.  相似文献   
95.
Issues and Techniques in Networked-Based Distributed Healthcare: Overview   总被引:1,自引:0,他引:1  
For telemedicine to reach its potential in the Internet2 environment,significant progress must be made in a number of areas. The emergingtelecommunications will include the Internet2 between medicalinstitutions and emerging broadband loop and wireless technologiesfor interconnections to homes. Within the technical environment,problems that must be addressed include the development of robotic-controlled,remote-monitoring devices unique to the various medical specialties;the encoding, transmission, and decoding of raw data specificto the specialized needs of various medical application areas;and the reduction of data for storage and retrieval in patientrecords. Institutionally, human factor and information accessissues with respect to physicians, patients, and non-physicianhealthcare providers must be addressed; healthcare insuranceprovider policies, government regulation, and state licensinglaws must be adapted for a new paradigm of healthcare delivery;and the philosophy of capital investment for the delivery ofhealthcare must be revised.Many current practiceswill be supplanted by home healthcare alternatives, the use ofpatient-initiated preventive healthcare initiatives, and remote-clinicactivity. These applications will result in central record archivingsystems; the need for encryption schemes, virus protection, andvandalism protection; extensive, additional connectivity betweenhealthcare providers and professionals; and new commercial playersin the healthcare arena.The hot applicationareas will include women's health, children's health, healthcarefor senior citizens, home healthcare, well-patient monitoring,and early-detection of medical problems.  相似文献   
96.
Process flight simulation tools can help managers understand the dynamics of new processes and technologies before they are introduced. This article tells how these exploratory tools can be used for IS project management, simple modeling of the software process, and modeling the dynamics of the IS organization in transition.  相似文献   
97.
HIV seroconversion as a result of an occupational exposure is a terrifying concern of healthcare workers who deliver care to patients in a variety of health care settings. In this article the most recent CDC guidelines for the management of HIV exposure and postexposure prophylaxis are reviewed. Prevention of bloodborne pathogen exposures, specifically through the selection of safety devices, is recognized as an important issue.  相似文献   
98.
辽宁省凌源县牛河梁出土的炉壁研究   总被引:3,自引:1,他引:2  
在牛河梁的一座人工建造的金字塔顶部发现的,被认定是从其它地方迁移过去的炉壁残片及其粘附的炉渣是辽西地区年代最早的冶铜遗物,热释光测定其年代为距今300~3500年,属夏家店下层化,炉渣含镁较高,夹杂有各种粒度的纯铜颗粒财质广场 河梁附近有多处古代开采遗迹的铜矿点,其脉石矿物也含有较高的镁,这些事实表明这些炉壁残片及其粘附的炉渣是冶炼当地氧化矿石的遗物,炉壁残片结果显示,炼炉上部内径约25cm,有  相似文献   
99.
This article proposes a standard, easy-to-interpret effect size estimate for one-sample research. The proportion index (π) shows the hit rate on a scale on which .50 is always the null value regardless of the number of equally likely choices. The index π is useful in the design of one-sample research because it can guide the best choice of number of response alternatives. Significance tests and confidence limits are readily computed. For meta-analyses of one-sample studies, tests of heterogeneity of a set of πs and contrasts among them are described. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
A diverse family of protein 4.1R isoforms is encoded by a complex gene on human chromosome 1. Although the prototypical 80-kDa 4.1R in mature erythrocytes is a key component of the erythroid membrane skeleton that regulates erythrocyte morphology and mechanical stability, little is known about 4.1R function in nucleated cells. Using gene knockout technology, we have generated mice with complete deficiency of all 4.1R protein isoforms. These 4.1R-null mice were viable, with moderate hemolytic anemia but no gross abnormalities. Erythrocytes from these mice exhibited abnormal morphology, lowered membrane stability, and reduced expression of other skeletal proteins including spectrin and ankyrin, suggesting that loss of 4. 1R compromises membrane skeleton assembly in erythroid progenitors. Platelet morphology and function were essentially normal, indicating that 4.1R deficiency may have less impact on other hematopoietic lineages. Nonerythroid 4.1R expression patterns, viewed using histochemical staining for lacZ reporter activity incorporated into the targeted gene, revealed focal expression in specific neurons in the brain and in select cells of other major organs, challenging the view that 4.1R expression is widespread among nonerythroid cells. The 4.1R knockout mice represent a valuable animal model for exploring 4.1R function in nonerythroid cells and for determining pathophysiological sequelae to 4.1R deficiency.  相似文献   
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