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Two experiments addressed the issue of whether endorsement of a position by a numerical majority or a minority leads to greater scrutiny of the information presented in a persuasive message. In Exp 1, a counterattitudinal position was endorsed by a majority or a minority and was supported by strong or weak arguments. Argument quality had a larger impact on attitudes with majority than with minority endorsement. In Exp 2, a proattitudinal or a counterattitudinal message was endorsed by a majority or a minority and was supported by strong or weak arguments. When the source and message position were unexpected (i.e., majority-counter and minority-pro messages), argument quality had a larger impact on attitudes than when the source and message position were expected (i.e., majority-pro and minority-counter messages). Thus, either majority or minority endorsement can enhance message scrutiny if the source-position pairing is surprising. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
This SAEM position paper clarifies the role of emergency medicine in health care delivery. It builds upon the working definition of emergency medicine developed by the American College of Emergency Physicians in 1994 by describing the health care role of emergency physicians (EPs). EPs are first-contact providers who care for all patients regardless of age, gender, time of presentation, or ability to pay. They remain the only continuously accessible specialty for patients seeking help and solace in the health care system. They are an essential link in the health care continuum between primary care physicians, specialists, the out-of-hospital system, the patient, inpatient services, and communication services. The EP's role is in organizing and monitoring the emergency care delivery system. Part of this role is to better align the health care provider training and ability with the specific medical needs of a patient. The emergency health care system remains the essential medical safety net for all individuals needing care in this country.  相似文献   
4.
Inkjet-Printed Polymer Films for the Detection of Organic Vapors   总被引:1,自引:0,他引:1  
Inkjet printing has been used to prepare polymeric thin films for gas sensing. The conductive polymer poly(3,4-ethylene dioxythiophene) doped with polystyrene sulfonated acid (PEDOT-PSS) was used as the organic ink. The electrical resistance of the printed films was monitored during exposure to atmospheres containing alcohol vapors. Thin films (one to two printed layers) exhibited a sharp, nonreversible increase in film resistance (a "chemical fuse") which was attributed to a change in morphology of the PEDOT-PSS layer. The response time of the thin films was 6-10 min, depending on the film thickness. A longer response time was observed for three inkjet-printed layers. In contrast, thick films (> four printed layers) showed a reversible response (except for the initial exposure) to the same vapor. This was thought to originate from a screening effect between the positively charged PEDOT and negatively charged PSS dopant. The response times of the thick films were 8 and 6 min for methanol and ethanol, respectively. For both types of response, the inkjet-printed layers were found be more sensitive to methanol (0.05% ppm-1) than to ethanol (0.03% ppm-1)  相似文献   
5.
Crystal structures have been determined of recombinant human tumor necrosis factor-alpha (TNF-alpha) and its R31D mutant that preferentially binds to TNF receptor R1 with more than seven times the relative affinity of binding to receptor R2. Crystals of the wild-type TNF were of space group P4(1)2(1)2 and had unit cell dimensions of a = b = 94.7 and c = 117.4 A. Refinement of the structure gave an R-factor of 22.3% at 2.5 A resolution. The crystals of TNF R31D mutant diffracted to 2.3 A resolution, and were of identical space group to the wild type with unit cell dimensions of a = b = 95.4 and c = 116.2 A, and the structure was refined to an R-factor of 21.8%. The trimer structures of the wild-type and mutant TNF were similar with a root mean square (r.m.s.) deviation of 0.56 A for Calpha atoms; however, the subunits within each trimer were more variable with an average r.m.s. deviation of 1.00 A on Calpha atoms for pairwise comparison of subunits. Model complexes of TNF with receptors R1 and R2 have been used to predict TNF-receptor interactions. Arg31 in all three subunits of wild-type TNF is predicted to form an ionic interaction with the equivalent glutamic acid in both receptors R1 and R2. Asp31 of the TNF R31D mutant is predicted to interact differently with the two receptors. The side chain of Asp31 in two subunits of the TNF mutant is predicted to form hydrogen bond interactions with Ser59 or Cys70 of R1, while it has no predicted interactions with R2. The loss of three strong ionic interactions of Arg31 and the electrostatic repulsion of Asp31 with Glu in the receptors is consistent with the reduced binding of the R31D mutant to both receptors relative to wild-type TNF. The replacement of these ionic interactions by two weaker hydrogen bond interactions between Asp31 of the R31D mutant and R1, compared with no interactions with R2, is in agreement with the observed preferential binding of the R31D mutant to R1 over R2. Analysis of the structure and function of receptor-discriminating mutants of TNF will help understand the biological role of TNF and facilitate its use as an antitumor agent.   相似文献   
6.
The hot-face refractory lining is a key component of gasification systems. The refractory liner protects the gasification system from the high-temperature corrosive gaseous and from the molten slag environment associated with the conversion of carbon feedstocks. This paper will discuss the effect of gasifier operating conditions and carbon feedstock slag/ash chemistry on the refractory service life. Particular attention is focused on the wear mechanism of chromia refractories, determined through postmortem analysis of spent refractory bricks from service in gasifiers. Also presented is the behavior of a phosphate-containing chromia refractory with improved resistance to structural spalling.  相似文献   
7.
如今,各国政府都在寻找可以通过少量投入实现强大新功能的科技。只要有追求创新的精神和持之以恒的努力,大多数城市都可以实现可持续发展的智能技术解决方案,从而降低成本,提高市政服务水平,改善市民的生活质量。微软委托IDC进行的一项最新研究指出,通过整合零散数据,采用新型数据分析工具,并向更多人传递有用的洞察,全球各国的政府机构在未来四年内从数据挖掘中获得的数据红利将高达2060亿美元,并且越早采用,收益越大。  相似文献   
8.
导读 目前,控制合规成本仍是企业的工作重点之一。其中的难点在于如何在恰当的时间将正确的“内容”保存在适宜的地方。依据传统的做法,企业在对数据归档时只是一味地对数据无限制的存储,无法经济高效地从长远解决数据保留问题。  相似文献   
9.
Evolution-in-materio uses evolutionary algorithms to exploit properties of materials to solve computational problems without requiring a detailed understanding of such properties. We show that using a purpose-built hardware platform called Mecobo, it is possible to solve computational problems by evolving voltages and signals applied to an electrode array covered with a carbon nanotube–polymer composite. We demonstrate for the first time that this methodology can be applied to function optimization and also to the tone discriminator problem (TDP). For function optimization, we evaluate the approach on a suite of optimization benchmarks and obtain results that in some cases come very close to the global optimum or are comparable with those obtained using well-known software-based evolutionary approach. We also obtain good results in comparison with prior work on the tone discriminator problem. In the case of the TDP we also investigated the relative merits of different mixtures of materials and organizations of electrode array.  相似文献   
10.
During the late 1990s and early 2000s, the profile of global manufacturing has experienced many changes. There is anecdotal evidence that many western manufacturing companies have chosen to expand their manufacturing base across geographical boundaries. The common reasons sited for these ventures are to exploit less expensive labour markets, to establish a presence in expanding markets and in response to the threat of new competition. Whilst a global manufacturing base can prove to have many cost and sales benefits, there are also many disadvantages. Logistics operations can often increase in complexity leading to higher reliance on planning and effective interpretation of demand data. In response, systems modelling has remerged as a fertile research area after many years. Many modelling and simulation techniques have been developed, but these have had very limited practical success. The authors have identified that majority of these simulation techniques rely upon a detailed market structure being known, when this is rarely the case. This paper describes the outcome of a research project to develop of a pragmatic set of tools to gather, assess and verify supply chain structure data. A hybrid collection of technologies are utilised to assist these operations and to build a dynamic supply network model.  相似文献   
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