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1.
The outbreak of a novel influenza A (H1N1) virus across the globe poses a threat to human health. It is of paramount importance to develop a rapid, reliable and inexpensive diagnostic procedure. Based on the bioinformatic information from public database, primers specific for influenza A virus surface protein haemagglutinin (HA) of several subtypes (including H1, H2, H3, H5, H7 and H9) were designed. Primer-specific PCR products were subiected to sequencing for accurately distinguishing H1 and H3 subtypes from others. This sequencing-based detection method will not only be applied to rapid detection and simultaneous subtype identification of new influenza A virus H1N1, but also provide the strategies to monitor other new types of influenza virus with explosive potential.  相似文献   
2.
宏观引力系统,比如黑洞,与非引力系统在热力学方面很不一样,其态函数熵与温度本质上是量子的,没有经典对应,因此对应的热力学在一定意义上来说本质上也是量子的,这为探讨量子引力提供了一个重要窗口.本文综述讨论作者及其合作者近期一系列有关黑洞的高维推广黑膜(超弦/M-理论中的基本动力学客体)的热力学相、相变及相关的临界现象的工作,希望为建立M-理论的完整理论框架提供重要的非微扰信息.  相似文献   
3.
Linear polymers bearing the same functional groups as their corresponding adsorbents could be used as models to study the ad-sorption behaviors. However, the relationships between the data from model study and real adsorption have not been fully interpreted. In this work, three adsorbent (CP1-Zn2+, CP2-Zn2+ and CP3-Zn2+) and their corresponding linear models (P1-Zn2+, P2-Zn2+ and P3-Zn2+) were synthesized. The affinity constants (Ka) between these models and target peptide DFLAE (DE5) were obtained by isothermal titration calorimetry (ITC). Adsorption capacities and adsorption affinities were carried out by static adsorption and adsorption isotherm. The qualitative and quantitative relationships between affinity constants from model study and the real ad-sorption data were explored. This study was significant to bridge the model study with the real adsorption.  相似文献   
4.
Speech intelligibility (SI) is an important index for the design and assessment of speech purpose hall. The relationship between Chinese speech intelligibility scores in rooms and speech transmission index (STI) under diotic listening condition was studied using monaural room impulse responses obtained from the room acoustical simulation software Odeon in previous paper. The present study employs the simulated binaural room impulse responses and auralization technique to obtain the subjective Chinese speech intelligibility scores using rhyme test. The relationship between Chinese speech intelligi-bility scores and STI is built and validated in rooms using dichotic (binaural) listening. The result shows that there is a high correlation between Chinese speech intelligibility scores and STI using dichotic listening. The relationship between Chinese speech intelligibility scores and STI under diotic and dichotic listening conditions is also analyzed. Compared with diotic listening, dichotic (binaural) listening (an actual listening situation) can improve 2.7dB signal-to-noise ratio for Mandarin Chinese speech intelligibility. STI method can predict and evaluate the speech intelligibility for Mandarin Chinese in rooms for dichotic (binaural) listening.  相似文献   
5.
PP/TiO2复合材料的力学性能研究   总被引:6,自引:0,他引:6  
采用熔融共混法制备了PP/TiO2复合材料,并研究了TiO2的表面处理、含量及粒径对复合材料的拉伸强度和缺口冲击强度两大主要力学性能的影响.实验结果表明,钛酸酯类偶联剂能很好地改善TiO2粒子与PP基体的界面相容性,从而使复合材料的力学性能提高;经表面处理后的纳米TiO2所填充复合材料的力学性能明显优于普通TiO2(微米级);而且处理后的纳米TiO2在填充量为4%时对PP的增强增韧效果最佳.  相似文献   
6.
教育机智是教师在组织教学过程中必不可少的一种能力,本文从心理学的角度分析了构成教育机智的心理成分有:敏锐的观察力,记忆的准备性,思维的灵活性与敏捷性,良好的应激心态,沉着、冷静的个性品质等。  相似文献   
7.
超弦理论及其进展   总被引:1,自引:0,他引:1  
卢建新 《科学通报》2009,54(8):999-1007
综述了超弦/M理论的意义、重要性及其发展过程中的两次革命以及已经取得的成绩, 评述了该领域目前的研究现状和发展趋势, 探讨了该理论的研究如何帮助我们认识和理解一个量子引力理论以及包括引力在内的相互作用统一理论所需要满足的要求和条件. 该理论的研究也在一定程度上揭示了时空的本质和模糊性、相互作用的本质和模糊性, 以及在考虑非微扰效应下经典和量子之间存在的可能模糊性, 由此为该理论的进一步研究和完善给予启示.  相似文献   
8.
9.
Sixty-two geologically meaningful U-Pb dates were obtained by using SHRIMP technique for the detrital zircons in three metasedimentary rocks from stratigraphically uppermost parts of the Longshoushan Group in the present study. Eighty percents of these dates range from 1.7 Ga to 2.2 Ga with a peak at 1.8-2.0 Ga and twenty percents from 2.3 Ga to 2.7 Ga. The youngest detrital zircon is dated at 1724±19 Ma which is interpreted as the maximum depositional age of the metasedimentary rocks. Therefore, the age for the diagenesis and lithification of the original sedimentary rocks of the Longshoushan Group before the metamorphism must be younger than 1724±19 Ma. Comparison of the age histograms of these detrital zircons with the ages of the igneous rocks on the surrounding older massifs suggests that the sediments of the Longshoushan Group were most likely derived from the Alaxa Block and Tarim Craton. This implies that the affinity between Alaxa Block and Tarim Craton was strong and that they might have been a unified craton during middle-early Proterozoic time.  相似文献   
10.
Triploids,recognized to occur more frequently in natural and experimental populations of many species than previously appreciated,display important economic and biological values.Despite this,however,linkage analysis for triploids has not been well explored.We develop a statistical model for estimating and testing the linkage between molecular markers in a triploid population derived from a tetraploid and diploid parent.The model incorporates one important meiotic feature of tetraploids by which more homologous chromosomes pair with a greater likelihood than less homologous chromosomes.By implementing the EM algorithm within the maximum likelihood framework,the model provides a procedure for simultaneous estimation of the linkage and preferential pairing factor.The model accommodates the segregating patterns of pseudotest markers and intercross markers with different amounts of informativeness.The utility of the model was validated through a real data analysis and simulation studies.The model provides a statistical tool for linkage analysis in a triploid population by taking into account meiotic behavior of tetraploids.Results from the model will help to shed light on the genetic diversity and origin of a polyploid population.  相似文献   
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