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1.
包铭新 《东华大学学报(自然科学版)》1992,(3)
本文总结了中国与日本之间染织文化交流的历程和中国传统染织纹样的发展,分析了中国文化对日本染织纹样的影响,以及日本传统染织纹样异于中国的特点和日本风格的形成。作者认为:1.日本传统染织纹样在母题、形式、内涵和名称诸方面受到中国的影响极大;2.这种影响以唐代和宋元为甚,明代以后日本逐渐自成一家;3.被称为“和样意匠”的日本风染织纹样表现了日本独特的民族性和审美情趣,特别是日本人对色彩的特殊感觉和嗜好;4.主要是由于技术上的原因,日本在印染方面的成就高于织绣纹样方面的成就,中国则相反。 相似文献
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While operational qualification (OQ) is a well-established term within equipment qualification, users of equipment often become unsure when it comes to implementation. The biggest problem is how to select procedures and acceptance criteria. Should these be the vendor's specifications or should the users define their own limits, and, if so, how? Should all instruments of the same type have the same values or should these be optimized for each individual instrument? This article will provide an overall strategy and specific examples for HPLC on how to select procedures and acceptance limits that are based on efficient use of resources, on practicality and on the intended use of the equipment. 相似文献
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Network motif is defined as a frequent and unique subgraph pattern in a network, and the search involves counting all the possible instances or listing all patterns, testing isomorphism known as NP-hard and large amounts of repeated processes for statistical evaluation. Although many efficient algorithms have been introduced, exhaustive search methods are still infeasible and feasible approximation methods are yet implausible.Additionally, the fast and continual growth of biological networks makes the problem more challenging. As a consequence, parallel algorithms have been developed and distributed computing has been tested in the cloud computing environment as well. In this paper, we survey current algorithms for network motif detection and existing software tools. Then, we show that some methods have been utilized for parallel network motif search algorithms with static or dynamic load balancing techniques. With the advent of cloud computing services, network motif search has been implemented with MapReduce in Hadoop Distributed File System(HDFS), and with Storm, but without statistical testing. In this paper, we survey network motif search algorithms in general, including existing parallel methods as well as cloud computing based search, and show the promising potentials for the cloud computing based motif search methods. 相似文献
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CRISPR-Cas12a系统的反式切割活性在其识别特定的DNA激活序列后被激活,这不仅能实现特定DNA靶标的直接定量分析,同时也为构建针对多种生物标志物的体外传感体系带来了新的思路。然而,已有文献中所采用的双链DNA(dsDNA)和单链DNA(ssDNA)激活序列结构多种多样,缺乏全面、系统的设计指导原则。针对该问题,该文系统研究了不同结构的DNA激活序列对LbaCas12a反式切割活性的影响。通过对比研究,得出以下结论:(1)前间区序列邻近基序(PAM)位点有助于LbaCas12a更高效地靶向结合dsDNA激活序列和ssDNA激活序列;(2)PAM近端区域缺少序列片段会降低Cas12a-crRNA定位激活序列的效率;(3)删除PAM远端序列片段有利于增强LbaCas12a的反式切割活性;(4)由于省略了dsDNA解链过程,ssDNA激活序列在激活LbaCas12a的反式切割活性方面普遍比dsDNA激活序列产生的效果更好。根据这些发现,该文提出了一种LbaCas12a所青睐的高效激活序列结构,其激活的LbaCas2a反式酶切活性较采用含PAM位点的标准dsDNA激活序列高出3.7倍。研究结果为构建基于CRISPR-Cas12a的高效体外生物传感系统提供了重要支撑。 相似文献
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Dr. Luis Martín-Gomis Sairaman Seetharaman David Herrero Prof. Dr. Paul A. Karr Prof. Dr. Fernando Fernández-Lázaro Prof. Dr. Francis D'Souza Prof. Dr. Ángela Sastre-Santos 《Chemphyschem》2020,21(20):2254-2262
The effect of donor-acceptor distance in controlling the rate of electron transfer in axially linked silicon phthalocyanine-C60 dyads has been investigated. For this, two C60-SiPc-C60 dyads, 1 and 2 , varying in their donor-acceptor distance, have been newly synthesized and characterized. In the case of C60-SiPc-C60 1 where the SiPc and C60 are separated by a phenyl spacer, faster electron transfer was observed with kcs equal to 2.7×109 s−1 in benzonitrile. However, in the case of C60-SiPc-C60 2 , where SiPc and C60 are separated by a biphenyl spacer, a slower electron transfer rate constant, kcs=9.1×108 s−1, was recorded. The addition of an extra phenyl spacer in 2 increased the donor-acceptor distance by ∼4.3 Å, and consequently, slowed down the electron transfer rate constant by a factor of ∼3.7. The charge separated state lasted over 3 ns, monitoring time window of our femtosecond transient spectrometer. Complimentary nanosecond transient absorption studies revealed formation of 3SiPc* as the end product and suggested the final lifetime of the charge separated state to be in the 3–20 ns range. Energy level diagrams established to comprehend these mechanistic details indicated that the comparatively high-energy SiPc.+-C60.− charge separated states (1.57 eV) populated the low-lying 3SiPc* (1.26 eV) prior returning to the ground state. 相似文献
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367名幼儿智力发育与血中五种元素相关性分析 总被引:2,自引:0,他引:2
为探讨血铜、锌、钙、镁、铁5种元素对儿童智力的影响及其相关性,采用首都儿科研究所编制的0—6岁儿童神经心理发育量表,对367名2—4岁儿童进行现场智力测试并对抚养人进行问卷调查;采集其指尖末梢血,运用原子吸收光谱仪检测了儿童血铜、锌、钙、镁、铁5种元素含量。结果表明,调查对象血铜、锌、钙、镁、铁5种元素低下,检出率分别为25.1%、76.6%、5.7%、1.4%、37.1%,城乡儿童全血铜、锌、钙存在明显差异(P〈0.05);儿童智力低下检出率为2.4%,儿童智能发育与其年龄、母亲文化水平、是否接受学前教育、血锌、铁呈正相关,与血钙、铜呈负相关。提示该地区2—4岁儿童血铜、锌、铁低下检出率较高,智能发育总体较为合理,但受血铜、锌、铁等多种因素影响,提高父母文化素质,加强儿童早期教育及营养有助于促进儿童智能发育。 相似文献
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Recently,self-sustained oscillatory genetic regulatory networks(GRNs) have attracted significant attention in the biological field.Given a GRN,it is important to anticipate whether the network could generate oscillation with proper parameters,and what the key ingredients for the oscillation are.In this paper the ranges of some function-related parameters which are favorable to sustained oscillations are considered.In particular,some oscillatory motifs appearing with high-frequency in most of the oscillatory GRNs are observed.Moreover,there are some anti-oscillatory motifs which have a strong oscillation repressing effect.Some conclusions analyzing these motif effects and constructing oscillatory GRNs are provided. 相似文献
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