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81.
Gold Nanorods,DNA Origami,and Porous Silicon Nanoparticle‐functionalized Biocompatible Double Emulsion for Versatile Targeted Therapeutics and Antibody Combination Therapy 下载免费PDF全文
82.
DNA‐Metalization: Synthesis and Properties of Novel Silver‐Containing DNA Molecules (Adv. Mater. 24/2016) 下载免费PDF全文
83.
Imparting Designer Biorecognition Functionality to Metal–Organic Frameworks by a DNA‐Mediated Surface Engineering Strategy 下载免费PDF全文
Weiyu Ning Zhenghan Di Yingjie Yu Pingmei Zeng Chunzhi Di Daquan Chen Xueqian Kong Guangjun Nie Yuliang Zhao Lele Li 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(11)
Surface functionality is an essential component for processing and application of metal–organic frameworks (MOFs). A simple and cost‐effective strategy for DNA‐mediated surface engineering of zirconium‐based nanoscale MOFs (NMOFs) is presented, capable of endowing them with specific molecular recognition properties and thus expanding their potential for applications in nanotechnology and biotechnology. It is shown that efficient immobilization of functional DNA on NMOFs can be achieved via surface coordination chemistry. With this strategy, it is demonstrated that such porphyrin‐based NMOFs can be modified with a DNA aptamer for targeting specific cancer cells. Furthermore, the DNA–NMOFs can facilitate the delivery of therapeutic DNA (e.g., CpG) into cells for efficient recognition of endosomal Toll‐like receptor 9 and subsequent enhanced immunostimulatory activity in vitro and in vivo. No apparent toxicity is observed with systemic delivery of the DNA–NMOFs in vivo. Overall, these results suggest that the strategy allows for surface functionalization of MOFs with different functional DNAs, extending the use of these materials to diverse applications in biosensor, bioimaging, and nanomedicine. 相似文献
84.
Synthesis of Branched DNA Scaffolded Super‐Nanoclusters with Enhanced Antibacterial Performance 下载免费PDF全文
Lu Yang Chi Yao Feng Li Yuhang Dong Zhikun Zhang Dayong Yang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(16)
Metal nanoclusters (NCs) possess unique optical properties, and exhibit a wide variety of potential applications. DNA with robust molecular programmability is demonstrated as an ideal scaffold to regulate the formation of NCs, offering a rational approach to precisely tune the spatial structures of NCs. Herein, the first use of branched DNA as scaffold to regulate the formation of silver nanoclusters (super‐AgNC) is reported, in which the spatial structures are precisely designed and constructed. Super‐AgNC with tunable shapes and arm‐lengths including Y‐, X‐, and (Y–X)‐ shaped super‐AgNC is achieved. The molecular structures and optical properties of super‐AgNCs are systemically studied. As a proof of application, remarkably, super‐AgNCs exhibit superior antibacterial performance. In addition, super‐AgNCs show excellent biocompatibility with three types of tissue cells including 293T (human embryonic kidney cells), SMCs (vascular smooth muscle cells), and GLC‐82 (lung adenocarcinoma cells). These performances enable the super‐AgNCs adaptable in a variety of applications such as biosensing, bioimaging, and antibacterial agents. 相似文献
85.
针对视频图像中单个运动目标的分割问题,提出了一种基于Kirsch边缘算子的视频运动目标分割算法,该算法将Kirsch算子检测到的边缘作为主分割信息,运动矢量场作为次要分割信息;首先利用双重尺度的运动矢量场进行累加和滤波处理来获得辅助分割信息;然后将Kirsch算子的模板分解为差值模板和公共模板以提高边缘的抗噪性;最后用自适应状态标记的方法将边缘信息和运动矢量信息相融合来准确地分割运动目标;实验结果表明该方法分割比较精确。 相似文献
86.
Y. Li G. C. L. Wong E. Caine E. L. Hu C. R. Safinya 《International Journal of Thermophysics》1998,19(4):1165-1174
We have used lithographically patterned microchannel arrays with channel widths ranging from 1 to 20 m, fabricated using electron beam lithography and reactive ion etching, in structural studies of DNA–cationic lipid complexes in confinement. Various techniques have been developed for loading these DNA–membrane complexes into the microchannels or to form the complexes in situ by sequentially depositing DNA and lipid solutions into the microchannels. Optical microscopy studies indicate that such complex formation is strongly influenced by the periodic channel structure even at channel widths much larger than the persistent length of the DNA molecules. Preliminary x-ray diffraction experiments conducted at Stanford Synchrotron Radiation Laboratory (SSRL) yielded only a weak signal from the lipid bilayers in the complexes. The use of a microfocused x-ray beam produced by the newly developed Bragg–Fresnel optics at a third-generation synchrotron facility may dramatically increase the signal-to-noise ratio and allow observation of orientational as well as positional ordering of DNA molecules induced by the microchannels. Structural control of the DNA–membrane complexes has a broad range of potential applications in gene probe technology and as mesoscopic biomolecular composites. 相似文献
87.
Michael D. Barrus 《Information Processing Letters》2010,110(7):261-263
An antimagic labeling of a connected graph with m edges is an injective assignment of labels from {1,…,m} to the edges such that the sums of incident labels are distinct at distinct vertices. Hartsfield and Ringel conjectured that every connected graph other than K2 has an antimagic labeling. We prove this for the classes of split graphs and graphs decomposable under the canonical decomposition introduced by Tyshkevich. As a consequence, we provide a sufficient condition on graph degree sequences to guarantee an antimagic labeling. 相似文献
88.
This paper proposes a mathematical model, valid inequalities and polyhedral results for the minimum labeling Hamiltonian cycle problem. This problem is defined on an unweighted graph in which each edge has a label. The aim is to determine a Hamiltonian cycle with the least number of labels. We also define two variants of this problem by assigning weights to the edges and by considering the tour length either as an objective or as a constraint. A branch-and-cut algorithm for the three problems is developed, and computational results are reported on randomly generated instances and on modified instances from TSPLIB. 相似文献
89.
M.W. Shinwari M.F. Shinwari M.J. Deen P.R. SelvaganapathyAuthor vitae 《Sensors and actuators. B, Chemical》2011,160(1):441
As the design of label-free DNA biosensors matures, and their sizes reduced to enhance their sensitivity, not much has been researched about the variations in the received signal with the positioning of the probes on the sensitive surface. We approach this issue computationally in this paper. By adopting the finite-element model on a three-dimensional biological field-effect transistor (BioFET) slice, and running Monte-Carlo simulations on the positions of the DNA molecules, we extract the expected variations in the signal. Then, we show that signal-to-noise (SNR) ratio can be low enough to hinder the functionality of the device, placing a limitation on how low the sensitivity of a sensor of a certain size can be. 相似文献
90.