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101.
Joshua D Shofner Juan G Vasquez Carole L Berger Richard L Edelson 《Journal of immune based therapies and vaccines》2007,5(1):2-11
Background
The malignant cells of cutaneous T cell lymphoma (CTCL) display immunogenic peptides derived from the clonal T cell receptor (TCR) providing an attractive model for refinement of anti-tumor immunization methodology. To produce a clinically meaningful anti-tumor response, induction of cytotoxic anti-CTCL cells must be maximized while suppressive T regulatory cells (Treg) should be minimized. We have demonstrated that engulfment of apoptotic CTCL cells by dendritic cells (DC) can lead to either CD8 anti-CTCL responses or immunosuppressive Treg induction. Treg generation is favored when the number of apoptotic cells available for ingestion is high. 相似文献102.
以680nm处的透光率作为澄清度的指标,比较明胶、淀粉、蛋清和壳聚糖4种澄清剂在不同浓度、温度、处理时间下的澄清效果。结果表明:明胶和壳聚糖澄清效果较好,蛋清次之,而淀粉几乎无澄清作用。0.16%的明胶和0.08%的壳聚糖澄清效果最佳,透光率分别为84.02%和84.44%。蛋清的澄清速度较明胶和壳聚糖慢;温度对蛋清和壳聚糖几乎无影响,但明胶随处理温度升高透光率下降。 相似文献
103.
第二代测序序列比对方法综述 总被引:1,自引:0,他引:1
使用聚合酶合成技术的Illumina和454平台以及使用连接酶合成测序技术的SOLiD平台是目前三种主流的第二代测序平台.对第二代测序平台产生的高通量序列片段进行比对的方法一般分为两步:①预处理,②序列比对.预处理方法有两类,即基于哈希表的方法和基于后缀trie的Burrows-Wheeler转换思想.序列比对方法也可分为两类,一是空位种子片段索引,二是Smith-Waterman动态规划算法.本文使用Illumina和SOLiD两种平台产生的数据对常用的比对软件SHRiMP,MAQ,BFAST,BWA,BOWTIE等进行了单机测试,结果显示:BOW-TIE在对Illumina平台数据进行比对时,在内存使用、比对速度以及准确性等方面表现比其他几种好,BWA比较适合用于比对SOLiD平台产生的数据.在处理第二代以及以纳米孔技术为标志的第三代测序平台高通量数据时,第二代比对技术仍不能完全满足要求,本文认为以云计算为基础的新序列比对方法是未来研究和发展的一个重要方向. 相似文献
104.
Jos A. Gmez-Pedrero Juan A. Quiroga M. Jos Terrn-Lpez Daniel Crespo 《Optics and Lasers in Engineering》2006,44(12):1297-1310
In this paper we present the application of a direct demodulation method for the measurement of surface topography by means of Shadow-Moiré. In our set-up, we use three LEDs (with green, red and blue peak wavelengths) to illuminate the grating. Due to the different position of these light sources, a polychromatic Shadow-Moiré fringe pattern is produced, which can be described as the superposition of three monochromatic (red, green and blue) fringe patterns. Taking the image of this polychromatic fringe pattern with a RGB CCD camera, we get a monochromatic fringe pattern stored at each RGB channel of the CCD. The direct demodulation algorithm employed uses these fringe patterns to calculate the wrapped phase map. After unwrapping the phase map using a standard multi-grid technique, we implemented an automatic procedure to detect the area of interest of the phase map by removing low modulation zones and to calculate the absolute value of the phase. In this way it is possible to determine the topography of a surface with a single RGB snapshot maintaining a simple experimental set-up, which is an important feature, especially for the study of dynamic phenomena such as deformations. We present the experimental results obtained after measuring different objects with both smooth and rough surface textures. 相似文献
105.
106.
Ultrasonic study of wheat flour properties 总被引:1,自引:0,他引:1
In this work, the wheat flour properties are investigated using ultrasound techniques. Moreover, the flour samples were also characterized by means of well established techniques such as protein content, Alveograph and Mixolab®. A set of 35 dough samples, made of wheat flours with diverse physical and quality properties, were studied. The obtained results shown that ultrasound measurements can detect changes in the dough consistency induced by proteins and also by gelatinization of the starch. Furthermore, ultrasound measurements can be related to parameters indicative of the proteolytic degradation or softening of the dough due to protease activity. Thus, ultrasound can be considered a low cost and rapid tool, complementary to conventional test, for wheat flour characterization. 相似文献
107.
Synchronization of complex community networks with nonidentical nodes and adaptive coupling strength
In this Letter, the complex dynamical networks with community structure and nonidentical nodes are considered. The globally asymptotical synchronization of the time-delayed complex community networks onto any uniformly smooth state is studied. Some simple and useful criteria are derived by constructing an effective control scheme and adjusting automatically the adaptive coupling strength. Finally, the developed techniques are applied to two complex community networks which are respectively synchronized to a chaotic trajectory and a periodic orbit, and numerical simulations are provided to show the feasibility of the developed methods. 相似文献
108.
García-Meca C Hurtado J Martí J Martínez A Dickson W Zayats AV 《Physical review letters》2011,106(6):067402
We experimentally demonstrate a low-loss multilayered metamaterial exhibiting a double-negative refractive index in the visible spectral range. To this end, we exploit a second-order magnetic resonance of the so-called fishnet structure. The low-loss nature of the employed magnetic resonance, together with the effect of the interacting adjacent layers, results in a figure of merit as high as 3.34. A wide spectral range of negative index is achieved, covering the wavelength region between 620 and 806 nm with only two different designs. 相似文献
109.
In order to enhance the compatibility with plastic polymers, magnesium hydroxide sulfate hydrate (MHSH) nanowhiskers were modified through grafting methyl methacrylate (MMA) on the surface of the nanowhiskers by emulsion polymerization. The influences of the reaction time, MMA monomer content, adding speed of monomer and the reaction temperature on the grafting ratio were investigated. Thermogravimetry (TG), Fourier transform infrared (FT-IR) spectroscopy, X-ray powder diffraction (XRD), scanning electron microscope (SEM), energy-dispersive X-ray (EDX) spectroscopy and surface contact angle measurement were used to characterize the effect of surface modification. The results showed that the MHSH nanowhiskers were uniformly coated by polymethyl methacrylate (PMMA), and a well-defined core-shell hybrid structure of MHSH/PMMA was obtained. The surface contact angle of the hybrid whiskers increased to 87.32° from 12.71° and the whiskers surface was changed from hydrophilic to lipophilic. 相似文献
110.
WANG Yu-Sa CHEN Yong XU Yu-Peng WANG Juan CUI Wei-Wei LI Wei HAN Da-Wei ZHANG Zi-Liang CHEN Tian-Xiang LI Cheng-Kui YANG Yan-Ji LIU Xiao-Yan HUO Jia ZHANG Jun-Min ZHENG Yi-Qian 《中国物理C(英文版)》2010,34(12)
The Low Energy X-ray Instrument (LE) of the Hard X-ray Modulation Telescope (HXMT) uses the Swept Charge Device (SCD) to detect the X-rays in 1-15 keV. The performance of SCD is vulnerable to temperature. We analyzed the thermal condition of LE at different satellite working attitudes with the Finite Element Method (FEM). It is shown that the angle between the sunlight and the normal line of the barrier should be less them 26°, to keep the SCD detectors working in the required temperature range, i.e. -40 ℃ to -80 ℃. We find that the performance of LE is very stable in this temperature range, with a typical energy resolution of 160 eV at 5.9 keV. 相似文献