摘要翻译:
Jarzynski等式和涨落定理将平衡自由能差与功的非平衡测量联系起来。这些关系延伸到探索蛋白质和核酸有限时间热力学的单分子实验。实验误差和仪器噪声的影响以前没有考虑。在这里,我们提出了一种贝叶斯形式,用于从非平衡功测量中估计自由能变化,该方法补偿了仪器噪声,并结合了来自多个驱动协议的数据。我们重新分析了最近的一组实验,其中一个单一的RNA发夹是展开和再折叠使用光镊在三个不同的速度。有趣的是,最快和最远的平衡测量包含最少的仪器噪声,因此比一些缓慢、噪声更大、接近平衡的测量提供了更准确的自由能估计。本文提出的方法将扩大单分子实验的范围;它们可用于分析AFM、光镊和磁镊测量的数据。
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英文标题:
《Bayesian estimates of free energies from nonequilibrium work data in the
presence of instrument noise》
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作者:
Paul Maragakis, Felix Ritort, Carlos Bustamante, Martin Karplus, Gavin
E. Crooks
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最新提交年份:
2007
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分类信息:
一级分类:Physics 物理学
二级分类:Statistical Mechanics 统计力学
分类描述:Phase transitions, thermodynamics, field theory, non-equilibrium phenomena, renormalization group and scaling, integrable models, turbulence
相变,热力学,场论,非平衡现象,重整化群和标度,可积模型,湍流
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一级分类:Physics 物理学
二级分类:Soft Condensed Matter 软凝聚态物质
分类描述:Membranes, polymers, liquid crystals, glasses, colloids, granular matter
膜,聚合物,液晶,玻璃,胶体,颗粒物质
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英文摘要:
The Jarzynski equality and the fluctuation theorem relate equilibrium free energy differences to non-equilibrium measurements of the work. These relations extend to single-molecule experiments that have probed the finite-time thermodynamics of proteins and nucleic acids. The effects of experimental error and instrument noise have not previously been considered. Here, we present a Bayesian formalism for estimating free-energy changes from non-equilibrium work measurements that compensates for instrument noise and combines data from multiple driving protocols. We reanalyze a recent set of experiments in which a single RNA hairpin is unfolded and refolded using optical tweezers at three different rates. Interestingly, the fastest and farthest-from-equilibrium measurements contain the least instrumental noise, and therefore provide a more accurate estimate of the free energies than a few slow, more noisy, near-equilibrium measurements. The methods we propose here will extend the scope of single-molecule experiments; they can be used in the analysis of data from measurements with AFM, optical, and magnetic tweezers.
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PDF链接:
https://arxiv.org/pdf/707.0089