The relaxation property of both Eigen model and Crow-Kimura model with a single peak fitness landscape isstudied from phase transition point of view.We first analyze the eigenvalue spectra of the replication mutation ...The relaxation property of both Eigen model and Crow-Kimura model with a single peak fitness landscape isstudied from phase transition point of view.We first analyze the eigenvalue spectra of the replication mutation matrices.For sufficiently long sequences,the almost crossing point between the largest and second-largest eigenvalues locates theerror threshold at which critical slowing down behavior appears.We calculate the critical exponent in the limit of infinitesequence lengths and compare it with the result from numerical curve fittings at sufficiently long sequences.We find thatfor both models the relaxation time diverges with exponent 1 at the error(mutation)threshold point.Results obtainedfrom both methods agree quite well.From the unlimited correlation length feature,the first order phase transition isfurther confirmed.Finally with linear stability theory,we show that the two model systems are stable for all ranges ofmutation rate.The Eigen model is asymptotically stable in terms of mutant classes,and the Crow-Kimura model iscompletely stable.展开更多
脑小血管病常见于中老年人,可导致老年人行动障碍、情感障碍和认知功能下降或血管性痴呆,严重影响老年人的生活质量。脑血管内皮细胞功能障碍是脑小血管病(cerebral small vessel disease,CSVD)的使动因素之一。常见的口腔慢性口腔感染...脑小血管病常见于中老年人,可导致老年人行动障碍、情感障碍和认知功能下降或血管性痴呆,严重影响老年人的生活质量。脑血管内皮细胞功能障碍是脑小血管病(cerebral small vessel disease,CSVD)的使动因素之一。常见的口腔慢性口腔感染包括龋病、根尖周病,牙龈炎和牙周炎,所致的炎症状态和内皮细胞功能障碍或与脑小血管病的发生发展密切相关。本文旨在对口腔慢性感染性疾病与CSVD之间的潜在联系和研究现状做一综述。展开更多
The directed motion of Brownian particles is generated by a travelling asymmetric potential.The asymptotic behaviour of probability density of the particles at long time is a solitary wave.The Brownian particles can d...The directed motion of Brownian particles is generated by a travelling asymmetric potential.The asymptotic behaviour of probability density of the particles at long time is a solitary wave.The Brownian particles can do work against an external opposing force with high efficiency.The analytical expressions of the solitary wave and the efficiency of the Brownian particles are obtained.The average velocity and the efficiency of the particles depends strongly on the travelling speed and the asymmetry of the potential.展开更多
基金Supported in part by the National natural Science Foundation of China under Grant No.10675170Major State Basic Research Developing Program under Gant No.2007CB815003
文摘The relaxation property of both Eigen model and Crow-Kimura model with a single peak fitness landscape isstudied from phase transition point of view.We first analyze the eigenvalue spectra of the replication mutation matrices.For sufficiently long sequences,the almost crossing point between the largest and second-largest eigenvalues locates theerror threshold at which critical slowing down behavior appears.We calculate the critical exponent in the limit of infinitesequence lengths and compare it with the result from numerical curve fittings at sufficiently long sequences.We find thatfor both models the relaxation time diverges with exponent 1 at the error(mutation)threshold point.Results obtainedfrom both methods agree quite well.From the unlimited correlation length feature,the first order phase transition isfurther confirmed.Finally with linear stability theory,we show that the two model systems are stable for all ranges ofmutation rate.The Eigen model is asymptotically stable in terms of mutant classes,and the Crow-Kimura model iscompletely stable.
文摘脑小血管病常见于中老年人,可导致老年人行动障碍、情感障碍和认知功能下降或血管性痴呆,严重影响老年人的生活质量。脑血管内皮细胞功能障碍是脑小血管病(cerebral small vessel disease,CSVD)的使动因素之一。常见的口腔慢性口腔感染包括龋病、根尖周病,牙龈炎和牙周炎,所致的炎症状态和内皮细胞功能障碍或与脑小血管病的发生发展密切相关。本文旨在对口腔慢性感染性疾病与CSVD之间的潜在联系和研究现状做一综述。
基金The project supported by National Natural Science Foundation of China under Grant Nos. 10475008, 10675170, and 10435020, and the Department of Nuclear Physics of China Institute of Atomic Energy under Grant Nos. 11SZZ-200501 and 11SZZ-200601
基金Supported by the National Natural Science Foundation of China under Grant Nos.19975073the China Postdoctoral Science Foundation.
文摘The directed motion of Brownian particles is generated by a travelling asymmetric potential.The asymptotic behaviour of probability density of the particles at long time is a solitary wave.The Brownian particles can do work against an external opposing force with high efficiency.The analytical expressions of the solitary wave and the efficiency of the Brownian particles are obtained.The average velocity and the efficiency of the particles depends strongly on the travelling speed and the asymmetry of the potential.
