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61.
Gareth AD Hardy Nesrina Imami Mark R Nelson Ann K Sullivan Ron Moss Marlén MI Aasa-Chapman Brian Gazzard Frances M Gotch 《Journal of immune based therapies and vaccines》2007,5(1):6-12
Background
Fully functional HIV-1-specific CD8 and CD4 effector T-cell responses are vital to the containment of viral activity and disease progression. These responses are lacking in HIV-1-infected patients with progressive disease. We attempted to augment fully functional HIV-1-specific CD8 and CD4 effector T-cell responses in patients with advanced chronic HIV-1 infection. 相似文献62.
Rani Warsi Sullivan Mohsen Razzaghi Jutima Simsiriwong 《Mathematical Methods in the Applied Sciences》2011,34(2):140-146
The objective of this paper is to present an algorithm from which a rapidly convergent solution is obtained for Volterra integral equations of Hammerstein type. Such equations are often encountered when describing the response of viscoelastic materials where the time dependency of the material properties is often expressed in the form of a convolution integral. Frequently, singularity is encountered and often ignored when dealing with the constitutive equations of viscoelastic materials. In this paper, the singularity is incorporated in the solution and the iterative scheme used to solve the equation converges within six iterations to a typical toleration error of 10?5. The algorithm is applied to the strain response of a polymer under impulsive (constant) loading and the results show excellent correlation between the experimental and analytical solution. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
63.
Ester Buchaca Siud Pui Man Majid Motevalli Lesley Robson Alice Sullivan John Wilson 《Polyhedron》2009,28(18):4115-4121
The compounds diethyl-N-carbazolylmethylphosphonate 1 and diethyl-2-oxymethylphosphonate carbazole 2 have been synthesised and characterized by a range of techniques including NMR, absorption and emission spectroscopy, infrared, and mass spectroscopy. Compound 1 forms a 2:1 complex 3 with calcium nitrate and the single crystal X-ray diffraction structure of 3 is described. Titrations of 1 with Zn2+ and Ca2+ in ethanol reveal that the intrinsic fluorescence is only slightly perturbed in the presence of these metal ions in micromolar ethanol solutions. Compounds 1 and 2 are readily taken up and visualized in L929 fibrosarcoma and DRG (Dorsal root ganglia) cell lines. 相似文献
64.
Ellingson D Potts B Anderson P Burkhardt G Ellefson W Sullivan D Jacobs W Ragan R 《Journal of AOAC International》2010,93(6):1897-1904
An improved method for direct determination of available carbohydrates in low-level products has been developed and validated for a low-carbohydrate soy infant formula. The method involves modification of an existing direct determination method to improve specificity, accuracy, detection levels, and run times through a more extensive enzymatic digestion to capture all available (or potentially available) carbohydrates. The digestion hydrolyzes all common sugars, starch, and starch derivatives down to their monosaccharide components, glucose, fructose, and galactose, which are then quantitated by high-performance anion-exchange chromatography with photodiode array detection. Method validation consisted of specificity testing and 10 days of analyzing various spike levels of mixed sugars, maltodextrin, and corn starch. The overall RSD was 4.0% across all sample types, which contained within-day and day-to-day components of 3.6 and 3.4%, respectively. Overall average recovery was 99.4% (n = 10). Average recovery for individual spiked samples ranged from 94.1 to 106% (n = 10). It is expected that the method could be applied to a variety of low-carbohydrate foods and beverages. 相似文献
65.
利用溶液聚合和成酰胺反应合成了多功能梳状两亲性共聚物,聚(甲基丙烯酸-co-甲基丙烯酸十八酯)-(乙醇胺-乙二胺叶酸)(PSM-EE-FA).用红外光谱(FTIR),核磁共振(1H-NMR)及凝胶渗透色谱(GPC)表征了该聚合物的结构及分子量分布.实验结果证明合成了该聚合物,其数均分子量(Mn)为28600,多分散性为1.375.用该两亲梳状聚合物包覆油溶性CdSe/ZnS量子点,通过相转移作用,得到水溶性靶向量子点(PSM-EE-FA-QDs).该水溶性量子点溶液具有较好的稳定性.通过紫外-可见(UV-Vis)及荧光发射光谱分析对该量子点的光学性质进行研究.结果表明,PSM-EE-FA-QDs的紫外-可见光谱及荧光发射光谱峰形与原量子点基本一致.由于量子点表面聚合物层的形成,峰位发生少量红移.该量子点水溶液的荧光强度是原量子点氯仿溶液的98%,荧光产率是原量子点氯仿溶液的95%.动态光散射(DLS)及透射电镜(TEM)测试结果表明水溶性量子点分布均匀.合成的水溶性量子点不但光学性能稳定,而且聚合物及水溶性量子点的合成方法较为简便. 相似文献
66.
We present an experimental study of low temperature electronic transport in the hybridization gap of inverted InAs/GaSb composite quantum wells. An electrostatic gate is used to push the Fermi level into the gap regime, where the conductance as a function of sample length and width is measured. Our analysis shows strong evidence for the existence of helical edge modes proposed by Liu et al [Phys. Rev. Lett. 100, 236601 (2008)]. Edge modes persist in spite of sizable bulk conduction and show only a weak magnetic field dependence-a direct consequence of a gap opening away from the zone center. 相似文献
67.
Azucena O Crest J Kotadia S Sullivan W Tao X Reinig M Gavel D Olivier S Kubby J 《Optics letters》2011,36(6):825-827
We report a technique for measuring and correcting the wavefront aberrations introduced by a biological sample using a Shack-Hartmann wavefront sensor, a fluorescent reference source, and a deformable mirror. The reference source and sample fluorescence are at different wavelengths to separate wavefront measurement and sample imaging. The measurement and correction at one wavelength improves the resolving power at a different wavelength, enabling the structure of the sample to be resolved. 相似文献
68.
69.
二甲基亚砜中Dy和Co的电化学行为 总被引:1,自引:0,他引:1
利用循环伏安法和计时电流法研究了室温下Dy和Co在二甲基亚砜中的电化学行为Dy(Ⅲ)和Co(Ⅱ)在Pt电极上分别为一步不可逆还原为Dy(0),Co(0);研究了不同浓度的支持电解质对Dy(Ⅲ)的传递系数的影响;测定并得到0.01mol·dm 相似文献
70.
Extensive research work has been done in recent times to apply the triboluminescence (TL) phenomenon for damage detection in engineering structures. Of particular note are the various attempts to apply it in the detection of impact damages in composites and aerospace structures. This is because TL-based sensor systems have a great potential for wireless, in-situ and distributed (WID) structural health monitoring when fully developed. This review article highlights development and the current state-of-the-art in the application of TL-based sensor systems. The underlying mechanisms believed to be responsible for triboluminescence, particularly in zinc sulfide manganese, a highly triboluminescent material, are discussed. The challenges militating against the full exploitation and field application of TL sensor systems are also identified. Finally, viable solutions and approaches to address these challenges are enumerated. 相似文献