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211.
OBJECTIVE: To assess the impact and costs of coverage for tobacco dependence treatment benefits with no patient cost sharing for smokers with employer sponsored coverage in two large independent practice association (IPA) model health maintenance organisations (HMOs) in California, USA. METHODS: A randomised experimental design was used. 1204 eligible smokers were randomly assigned either to the control group, which received a self-help kit (video and pamphlet), or to the treatment group, which received the self-help kit and fully covered benefits for over the counter (OTC) nicotine replacement therapy (NRT) gum and patch, and participation in a group behavioural cessation programme with no patient cost sharing. RESULTS: The quit rates after one year of follow up were 18% in the treatment group and 13% in the control group (adjusted odd ratio (OR) 1.6, 95% confidence interval (CI) 1.1 to 2.4), controlling for health plan, sociodemographics, baseline smoking characteristics, and use of bupropion. Rates of quit attempts (adjusted OR 1.4, 95% CI 1.1 to 1.8) and use of nicotine gum or patch (adjusted OR 2.3, 95% CI 1.6 to 3.2) were also higher in the treatment group. The annual cost of the benefit per user who quit ranged from $1495 to $965 or from $0.73 to $0.47 per HMO member per month. CONCLUSIONS: Full coverage of a tobacco dependence treatment benefit implemented in two IPA model HMOs in California has been shown to be an effective and relatively low cost strategy for significantly increasing quit rates, quit attempts, and use of nicotine gum and patch in adult smokers.  相似文献   
212.
Thermal performance and phase change stability of myristic acid as a latent heat energy storage material has been studied experimentally. In the experimental study, the thermal performance and heat transfer characteristics of the myristic acid were tested and compared with other studies given in the literature. In the present study is included some parameters such as transition times, temperature range, and propagation of the solid–liquid interface as well as heat flow rate effect on the phase change stability of myristic acid as a phase change material (PCM). The experimental results showed that the melting stability of the PCM is better in the radial direction than the axial direction. The variety of the melting and solidification parameters of the PCM with the change of inlet water temperature is also studied. The results show that the better stability of the myristic acid was accomplished at low inlet water temperature compared with the obtained results at high inlet water temperature. We also observed that while the heat exchanger tube is in the horizontal position, the PCM has more effective and steady phase change characteristics than in the vertical position. The heat storage capacity of the container (PCM tube) is not as good as we expected in this study and the average heat storage efficiency (or heat exchanger effectiveness) is 54%. It means that 46% of the heat acrually lost somewhere.  相似文献   
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Kamil Kosiel 《Vacuum》2008,82(10):951-955
Molecular beam epitaxy (MBE) is presented as a powerful and flexible technology for research and development (R&D) as well as for mass production of nanoelectronic structures, based on a huge variety of materials. Its historical background, basic properties, advantages—in particular the production potential—as well as some trends in the field are shown.  相似文献   
215.
The authors tested the spatial memory of serially presented locations in Clark's nutcrackers (Nucifraga columbiana). Birds were serially presented with locations in an open room. The authors buried a seed in a sand-filled cup at each location and then tested nutcrackers for their memory for each location in the list by using the cluster method. For each item in the list, the authors opened a cluster of 6 holes. Accuracy was measured by how many tries were required for the bird to find the correct location within each cluster. In Experiments 1 and 2, the authors presented 2 lists of locations and found evidence for proactive and retroactive interference. Nutcrackers made errors by visiting the interfering list of locations during recovery of the target list. This finding demonstrates that nutcrackers are susceptible to proactive and retroactive interference during the recall of spatial information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
216.
In this work, an optical modulation spectroscopy technique: thermoreflectance has been employed to study temperature distributions on the surface of optically pumped vertical external cavity surface emitting lasers (VECSELs). The thermoreflectance is based on the relative change of reflectivity of the sample induced by the change of its temperature. In this case the temperature change of the sample is induced by operating the pump in pulse mode. We have investigated samples with and without intracavity heatspreader. The resulting temperatures and temperature distributions on the sample surface have been measured and compared with theoretical calculations. The results confirm the effectiveness of silicon carbide (SiC) heatspreader approach. This is also a first report on the direct temperature mapping on VECSELs, with micron spatial resolution.  相似文献   
217.
The triacylglycerol of Crambe abyssinica seeds consist of 95 % very long chain (>18 carbon) fatty acids (86 % erucic acid; 22:1?13) in the sn‐1 and sn‐3 positions. This would suggest that C. abyssinica triacylglycerols are not formed by the action of the phospholipid:diacylglycerol acyltransferase (PDAT), but are rather the results of acyl‐CoA:diacylglycerol acyltransferase (DGAT) activity. However, measurements of PDAT and DGAT activities in microsomal membranes showed that C. abyssinica has significant PDAT activity, corresponding to about 10 % of the DGAT activity during periods of rapid seed oil accumulation. The specific activity of DGAT for erucoyl‐CoA had doubled at 19 days after flowering compared to earlier developmental stages, and was, at that stage, the preferred acyl donor, whereas the activities for 16:0‐CoA and 18:1‐CoA remained constant. This indicates that an expression of an isoform of DGAT with high specificity for erucoyl‐CoA is induced at the onset of rapid erucic acid and oil accumulation in the C. abyssinica seeds. Analysis of the composition of the acyl‐CoA pool during different stages of seed development showed that the percentage of erucoyl groups in acyl‐CoA was much higher than in complex lipids at all stages of seed development except in the desiccation phase. These results are in accordance with published results showing that the rate limiting step in erucic acid accumulation in C. abyssinica oil is the utilization of erucoyl‐CoA by the acyltransferases in the glycerol‐3‐phosphate pathway.  相似文献   
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219.
The paper addresses the reliability change of a road bridge pile foundation due to the unpredictable increase of settlements in time. The analysis is based on the R?dziński Bridge in Wroc?aw, Poland, its design assumptions, and monitoring results. The bridge foundation rests on a multi-layered subsoil assumed random. The Finite Element model of the subgrade is generated in ZSoil® software. To simplify the probabilistic approach, substitute soil strata stiffness parameters are adopted. Tracing their time decrement allows for a comprehensive definition of the entire foundation over-settlement produced by numerous factors. Preliminary sensitivity analysis of settlements to the stiffness variation properly simplifies the random model. The Serviceability Limit State helps to assess the foundation reliability index, further compared with the condition in the EN 1990:2002/A1:2005 standard. In addition, real-life settlements are also measured in the first year of bridge operation, they are used to calibrate the reliability index assessment. An innovative approach is proposed, where appropriate time-wise fluctuation functions represent the expected settlement increase and the related reliability reduction. These fluctuation functions help to plan the future remedial actions to maintain the initial bridge safety and to indicate the action frequency and scope. Future reliability levels may be extrapolated too. The real-life survey database of settlements makes it possible to validate the results of probabilistic calculations. A dedicated flowchart is devised to support further analysis of a wide structural domain.  相似文献   
220.
正在这个现代化的时代,随着技术、软件、硬件的飞速发展以及尺寸的不断缩小,手持移动设备(如平板电脑、智能手机、照相机、GPS、PDA等)市场实现了跨越式增长。所有这些先进的设备都采用电池供电,这几年又新增了许多功能,如触摸屏、更宽的显示屏,还运行着多种连接至互联网的应用。所有这些都会增加能耗。电池尺寸和容量的发展速度跟不上电力需求增加的速度,因此需要更加频繁地充电。您需要随身携带充电器,并频繁地处理许多根线,虽  相似文献   
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