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排序方式: 共有276条查询结果,搜索用时 31 毫秒
41.
Prof. Arivazhagan Rajendran Kirankumar Krishnamurthy Seojeong Park Prof. Eiji Nakata Prof. Youngjoo Kwon Prof. Takashi Morii 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(22):e202200108
DNA minicircles exist in biological contexts, such as kinetoplast DNA, and are promising components for creating functional nanodevices. They have been used to mimic the topological features of nucleosomal DNA and to probe DNA-protein interactions such as HIV-1 and PFV integrases, and DNA gyrase. Here, we synthesized the topologically-interlocked minicircle rotaxane and catenane inside a frame-shaped DNA origami. These minicircles are 183 bp in length, constitute six individual single-stranded DNAs that are ligated to realize duplex interlocking, and adopt temporary base pairing of single strands for interlocking. To probe the DNA-protein interactions, restriction reactions were carried out on DNAs with different topologies such as free linear duplex or duplex constrained inside origami and free or topologically-interlocked minicircles. Except the free linear duplex, all tested structures were resistant to restriction digestion, indicating that the topological features of DNA, such as flexibility, curvature, and groove orientation, play a major role in DNA-protein interactions. 相似文献
42.
In this paper, we work with lattice spaces. (A lattice space is an ordered pair consisting of a set X and a lattice on X). As is known, each lattice measure µ induces six outer measures on P(X), one of which is the well-known "induced outer measure" µ*(in case µ is countably additive); the others are µ, µ, µ,, and
.In the first part of the paper, we consider an arbitrary lattice measure and discover various relationships involving two or more of the seven set functions under consideration, on P(X) and on various special subsets of P(X), under various conditions on the measure or on the lattice.In the second part of the paper, we consider two lattice measures related by "domination" and obtain similar results.In the third part of the paper, we consider two lattice measures related by "restriction" and obtain similar results. 相似文献
43.
Telomere length is an important measure of cell and tissue regenerative capacities. The mean telomere length is classically used as global indicator of a tissue telomere length. In skeletal muscle, which is made of postmitotic myonuclei and satellite cells (muscle stem cells), minimum telomere length is also used to assess the telomere length of satellite cells and newly incorporated myonuclei. At present, the estimation of the method reproducibility during the assessment of mean and minimum telomere length using Southern blot analysis has never been documented. The aim of this report is to describe a signal modelization for improved precision of assessment of minimum and mean telomere lengths and to document the method reproducibility. Telomeres are assessed using a Southern technique where the gel is directly hybridized with the specific probe without the membrane-transferring step in order to prevent telomeric low signal loss. We found that the improved signal analysis for determination of telomere length is associated with coefficients of variation ranging from 1.37 to 4.29% for the mean telomeric restriction fragment (TRF) length and from 2.04 to 4.95% for the minimum TRF length. Improved method reproducibility would allow saving time and biological material as duplicate and triplicate measurement of the same sample is no longer required. 相似文献
44.
Liangshen Duan Qin Nie Yongxin Hu Liming Wang Kaiyan Guo Zhuoyi Zhou Xu Song Yuanhong Tu Hui Liu Thomas Hansen Jian-song Sun Qingju Zhang 《Angewandte Chemie (International ed. in English)》2023,62(33):e202306971
Herein, we described the first synthesis of the pentasaccharide and decasaccharide of the A. baumannii ATCC 17961 O-antigen for developing a synthetic carbohydrate-based vaccine against A. baumannii infection. The efficient synthesis of the rare sugar 2,3-diacetamido-glucuronate was achieved using our recently introduced organocatalytic glycosylation method. We found, for the first time, that long-range levulinoyl group participation via a hydrogen bond can result in a significantly improved β-selectivity in glycosylations. This solves the stereoselectivity problem of highly branched galactose acceptors. The proposed mechanism was supported by control experiments and DFT computations. Benefiting from the long-range levulinoyl group participation strategy, the pentasaccharide donor and acceptor were obtained via an efficient [2+1+2] one-pot glycosylation method and were used for the target decasaccharide synthesis. 相似文献
45.
46.
With order statistics of the uniform distribution on [0, l], exponential and beta distributions, a stochastic representation
is obtained for the uniform distribution over various domains, where A-type domains are closely associated with reliability
growth analysis, order restricted statistical inference and isotonic regression theory, V-type domains are connected with
the mixture-amount experiments, and T-type domains are well related to mixture experiments. With these stochastic representations,
the corresponding uniform distribution and number-theoretic nets can be generated. This approach seems to be new and is called
order statistics method. Some examples on reliability growth analysis and experimental design are presented.
This work was partially supported by a Hong Kong UGC-RGC grant, the Statistics Research and Consultancy Centre of HK-BU, and
the Chinese Academy of Sciences. 相似文献
47.
The 0-1 Knapsack problem with a single continuous variable 总被引:5,自引:0,他引:5
Specifically we investigate the polyhedral structure of the knapsack problem with a single continuous variable, called the
mixed 0-1 knapsack problem. First different classes of facet-defining inequalities are derived based on restriction and lifting. The order of
lifting, particularly of the continuous variable, plays an important role. Secondly we show that the flow cover inequalities
derived for the single node flow set, consisting of arc flows into and out of a single node with binary variable lower and
upper bounds on each arc, can be obtained from valid inequalities for the mixed 0-1 knapsack problem. Thus the separation
heuristic we derive for mixed knapsack sets can also be used to derive cuts for more general mixed 0-1 constraints. Initial
computational results on a variety of problems are presented.
Received May 22, 1997 / Revised version received December 22, 1997 Published online November 24, 1998 相似文献
48.
在制造商存在产能约束下,建立了再制造闭环供应链回收渠道决策的Stackelberg博弈模型,得出了三种回收渠道下的回收率、零售价以及制造商、零售商和供应链的利润,分析了制造商的生产能力对回收渠道决策的影响。研究表明:存在产能约束时,制造商回收渠道中的回收率总是最高的,这与无产能约束时零售商回收渠道中回收率最高的情况明显不同;同时,若废旧产品回收转移支付价格较低,制造商会选择自己回收,此时的零售价最低,制造商、零售商和供应链利润最高;若回收转移支付价格较高,制造商会选择零售商回收,此时的零售价最低,制造商和供应链利润最高。 相似文献
49.
50.
Robert O. Bauer 《Journal of Mathematical Analysis and Applications》2009,349(2):469-474
We show that for the conformal restriction measure with exponent b in the unit disk on hulls γ connecting eix to 1 the probability of the event that γ avoids the disk of radius q centered at zero decays like exp(−bπx/(1−q)) if either b∈[5/8,1]∪[5/4,∞) and x∈(0,π], or if b∈(1,5/4), x∈(0,π), and bx?π. 相似文献