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1.
Based on the concept of genetics, this article studies the phenomenon of information communication and the characteristics of information itself. It points out that the comparability between genetics and information science is the basis of putting forward the concept of information DNA. Through a discussion on the application of some laws of genetics in information science research, this article demomtrates the rationality of putting forward the concept of information DNA. 相似文献
2.
Raúl J. Cano 《Endeavour》1996,20(4):162-167
Much of what we know about extinct organisms comes from traits that are not preserved in the fossil record. Until recently, morphological analysis was the only tool available for scientists to determine relationships for extinct fossil organisms. We now know that ‘ancient’ DNA can be preserved in the remains of extinct organisms. By targeting specific gene sequences, it may be possible to deduce biochemical characteristics and through sequence comparisons, to estimate the extent of evolutionary divergence. By comparing the amount and type of these changes, one could estimate how quickly some DNA ‘evolves’ relative to other segments, or which genes have the most flexibility or are more conserved over time. The compilation of these data would yield greater understanding of the physiology of extinct organisms and provide a much clearer picture of genetic change over time, and the mechanics behind ‘evolution’. 相似文献
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DNA纳米技术是设计和构建具有一定用途的人工核酸纳米结构。DNA纳米技术中的一个重要挑战就是如何有效设计和构建具有明确功能的纳米尺度的结构和器件。计算机辅助工具是预测、设计、建模以及描绘DNA结构的最强有力的工具。计算机辅助设计DNA结构以及识别有效的自组装路径让DNA作为一种独特的材料在构建纳米结构领域中显露锋芒。文章总结了DNA纳米结构设计的原理,介绍了一些用于DNA结构设计的算法以及一些用户友好软件。同时,对DNA纳米技术中构建DNA逻辑门以及DNA计算方面的最新研究进展做了介绍。 相似文献
7.
We report the profiling of the 5-methyl cytosine distribution within single genomic-sized DNA molecules at a gene-relevant resolution. This method linearizes and stretches DNA molecules by confinement to channels with a dimension of about 250×200 nm(2). The methylation state is detected using fluorescently labeled methyl-CpG binding domain proteins (MBD), with high signal contrast and low background. DNA barcodes consisting of methylated and non-methylated segments are generated, with both short and long concatemers demonstrating spatially resolved MBD binding. The resolution of the technique is better than 10 kbp, and single-molecule read-lengths exceeding 140 kbp have been achieved. 相似文献
9.
This paper presents a continuous flow microfluidic device for the separation of DNA from blood using magnetophoresis for biological applications and analysis. This microfluidic bio-separation device has several benefits, including decreased sample handling, smaller sample and reagent volumes, faster isolation time, and decreased cost to perform DNA isolation. One of the key features of this device is the use of short-range magnetic field gradients, generated by a micro-patterned nickel array on the bottom surface of the separation channel. In addition, the device utilizes an array of oppositely oriented, external permanent magnets to produce strong long-range field gradients at the interfaces between magnets, further increasing the effectiveness of the device. A comprehensive simulation is performed using COMSOL Multiphysics to study the effect of various parameters on the magnetic flux within the separation channel. Additionally, a microfluidic device is designed, fabricated, and tested to isolate DNA from blood. The results show that the device has the capability of separating DNA from a blood sample with a purity of 1.8 or higher, a yield of up to 33 μg of polymerase chain reaction ready DNA per milliliter of blood, and a volumetric throughput of up to 50 ml/h. 相似文献
10.
We present an application of a novel DNA separation matrix, cholesterol-bearing pullulan (CHP) nanogels, for microchip electrophoresis. The solution of the CHP showed a unique phase transition around 30 mg∕ml and formed gel phase over this critical concentration. This gel phase consists of the weak hydrophobic interactions between the cholesterols could be easily deformed by external forces, and thus, loading process of the CHP nanogels into microchannels became easier. The high concentration of the CHP nanogels provided excellent resolutions especially for small DNA fragments from 100 to 1500 bp. The separation mechanism was discussed based on Ogston and Reptation models which had developed in gels or polymer solutions. The result of a single molecule imaging gave us an insight of the separation mechanism and the nanogel structures as well. 相似文献
11.
In 1920, the German botanist Hans Winkler coined the concept of the ‘genome’. This paper explores the history of a concept that has developed in parallel with advances in biology and supports novel and powerful heuristic biological research in the 21st century. From a structural interpretation (the genome as the haploid number of chromosomes), it has changed to keep pace with technological progress and new interpretations of the material of heredity. In the first place, the ‘genome’ was extended to include all the material in the nucleus, then the sum of all genes, and (with the discovery of the structure of DNA) the sum of the nucleotide base sequences. In the early 21st century, it has become a much more complex and central concept that has spawned the growing field of studies referred to as the ‘omics’. 相似文献
12.
This paper assesses Sarkar's ([2003]) deflationary account ofgenetic information. On Sarkar's account, genes carry informationabout proteins because protein synthesis exemplifies what Sarkarcalls a ‘formal information system’. Furthermore,genes are informationally privileged over non-genetic factorsof development because only genes enter into arbitrary relationsto their products (in virtue of the alleged arbitrariness ofthe genetic code). I argue that the deflationary theory doesnot capture four essential features of the ordinary conceptof genetic information: intentionality, exclusiveness, asymmetry,and causal relevance. It is therefore further removed from whatis customarily meant by genetic information than Sarkar admits.Moreover, I argue that it is questionable whether the accountsucceeds in demonstrating that information is theoreticallyuseful in molecular genetics.
- Introduction
- Sarkar's InformationSystem
- The Pre-theoretic Features of Genetic Information
- 3.1Intentionality
- 3.2 Exclusiveness
- 3.3 Asymmetry
- 3.4 Causalrelevance
- 3.2 Exclusiveness
- 3.1Intentionality
- Theoretical Usefulness
- Conclusion
13.
作为一种业界隐喻,互联网基因意指产品的三个特征:产品成为互联网终端,服务依托云平台,需求感知敏捷化。三个特征的现实展开形成产品形态革命的趋势,即整体来看产品演变成"三位一体"的服务体系,动态来看服务体系通过迭代创新形成永续生命周期,宏观来看服务体系之间互联互通从而形成智能生产网络。互联网基因之所以颠覆产业世界,根本原因在于能够以低成本创造出新价值。新价值主要是以产品或服务设施为载体在需求感知基础上提供的服务增加值,在线运营平台是实现这种增加值的核心资产,平台运营商依托平台资产能够对相关行业发动价值颠覆。文章以信息类终端产品、传统IT企业和中介行业为案例对此进行了说明,并强调在线运营平台将会成为各行各业的产业链中枢和竞争焦点。最后从历史角度说明,互联网基因既符合产业服务化的一贯趋势,又是此趋势中的巨大飞跃,它超出了产业技术革命理论的ICT(信息、通信和技术)范式框架,所引起变革的深度堪比工业革命以来社会化大生产的出现。 相似文献
14.
DNA计算是近年来发展迅速的新兴计算技术,其与信息、数学、物理和纳米领域密切交叉。其信息并行处理速度快,且具有高度分子并行性的优势,得到了广泛的关注。经过近20年的发展,DNA计算在理论研究和实现方面都取得了十分重要的进展。作为未来新兴的计算技术,DNA计算有着巨大的应用潜力。文章对近年来DNA计算中运用的各类技术进行了总结:(1)基于链置换的DNA计算技术;(2)基于核酶的DNA计算技术;(3)基于瓦片的DNA计算技术;(4)基于纳米颗粒的DNA计算技术;(5)基于SiO2的DNA计算技术;(6)细胞内DNA计算技术;(7)其他DNA计算技术,包括表面DNA计算等。在此基础上,对未来DNA计算技术进行了展望并提出建议。 相似文献
15.
Using Monte Carlo simulations of a touching-bead model of double-stranded DNA, we show that DNA extension is enhanced in isosceles triangular nanochannels (relative to a circular nanochannel of the same effective size) due to entropic depletion in the channel corners. The extent of the enhanced extension depends non-monotonically on both the accessible area of the nanochannel and the apex angle of the triangle. We also develop a metric to quantify the extent of entropic depletion, thereby collapsing the extension data for circular, square, and various triangular nanochannels onto a single master curve for channel sizes in the transition between the Odijk and de Gennes regimes. 相似文献
16.
Maedeh Roushan Parminder Kaur Alena Karpusenko Preston J. Countryman Carlos P. Ortiz Shuang Fang Lim Hong Wang Robert Riehn 《Biomicrofluidics》2014,8(3)
We present an analytic technique for probing protein-catalyzed transient DNA loops that is based on nanofluidic channels. In these nanochannels, DNA is forced in a linear configuration
that makes loops appear as folds whose size can easily be quantified. Using this technique, we study
the interaction between T4 DNA ligase and DNA. We find that T4 DNA ligase binding changes the physical characteristics of the DNA
polymer, in particular
persistence length and effective width. We find that the rate of DNA fold unrolling is significantly reduced
when T4 DNA ligase and ATP
are applied to bare DNA.
Together with evidence of T4 DNA ligase bridging two different segments of DNA based on AFM imaging, we thus conclude that ligase
can transiently stabilize folded
DNA configurations by coordinating genetically distant DNA stretches. 相似文献
17.
YAN Fusheng 《中国科学院院刊(英文版)》2019,(1)
<正>Scientists have long been seeking to spontaneously spot and cure human diseases by using smart nanorobots.In February 2018, a kind of DNA origami-based nanorobots for cancer therapy was devised by a combined team jointly led by Profs. NIE Guangjun, DING Baoquan and ZHAO Yuliang from the CAS National Center for Nanoscience and Technology(NCNST)based in Beijing, China and Prof. YAN Hao from Arizona State University, USA. Once introduced into the circulation, these 相似文献
18.
Recent simulations by Chen and Dorfman [Electrophoresis 35, 405–411 (2014)]
suggested that “tilting” the electric field with respect to the lattice vectors of a hexagonal post
array would lead to a substantial improvement in electrophoretic DNA separations therein. We
constructed such an array where the electric field is applied at an angle equidistant between the
two lattice vectors. This tilted array leads to (i) baseline resolution of 20 kbp DNA and λ DNA
(48.5 kbp) in a 4 mm channel and (ii) measurable separation resolutions for electric fields up to
50 V/cm, both of which are improvements over untilted post arrays of the same post density. The
predicted time required to reach a resolution of unity is approximately 5 min, independent of
electric field. The separations are more reproducible at higher fields. 相似文献
19.
《国家科学评论(英文版)》2014,(2)
Cytosine DNA methylation is an epigenetic modiication in eukaryotes that maintains genome integrity and regulates gene expression. he DNA methylation paterns in plants are more complex than those in animals,and plants and animals have common as well as distinct pathways in regulating DNA methylation. Recent studies involving genetic, molecular, biochemical and genomic approaches have greatly expanded our knowledge of DNA methylation in plants. he roles of many proteins as well as non-coding RNAs in DNA methylation have been uncovered. 相似文献
20.
近几年,DNA计算是诸多学科研究的一个热点。编码与模型选择是DNA计算的核心。本文综述了DNA计算原理,讨论了目前常用计算模型及进展。 相似文献