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Relaxation Property and Stability Analysis of the Quasispecies Models

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Communications in Theoretical Physics 2009年第10期52卷 726-734页

作者： FEGN Xiao-li li Yu-Xiao GU Jian-Zhong zhuo yi-Zhong School of Physical Engineering Zhengzhou University Zhengzhou 450052 China Center for Computational and System Biology Institute of Biophysics Chinese Academy of Science Beijing 100101 China China Institute of Atomic Energy P.O. Box 275（18） Beijing 102413 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

The relaxation property of both Eigen model and Crow-Kimura model with a single peak fitness landscape is studied 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 seeond-largest eigenvalues locates the error threshold at which critical slowing down behavior appears. We calculate the critical exponent in the limit of infinite sequence lengths and compare it with the result from numerical curve fittings at sufficiently long sequences. We find that for both models the relaxation time diverges with exponent 1 at the error （mutation） threshold point. Results obtained from both methods agree quite well. From the unlimited correlation length feature, the first order phase transition is further confirmed. Finally with linear stability theory, we show that the two model systems are stable for all ranges of mutation rate. The Igigen model is asymptotically stable in terms of mutant classes, and the Crow-Kimura model is completely stable.

关键词： relaxation time critical exponent error threshold

Small modifications of endo-functionalized cavities lead to large changes in molecular interaction in water

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Science China Chemistry 2025年第1期 369-376页

作者： Song-Meng Wang Hao Nian Yan-Fang Wang li-Shuo Zheng Yu-Tao Zheng yi-Wei Dong liping Huang Xiaoping Wang Wei Jiang liu-Pan Yang Department of Chemistry Southern University of Science and Technology School of Chemistry and Pharmaceutical Sciences State Key Laboratory for Chemistry and Molecular Engineering of Medicinal ResourcesGuangxi Normal University School of Pharmaceutical Science Hengyang Medical School University of South China

Studying molecular recognition in aqueous environments is crucial for understanding biological processes. Herein, we present a series of N-doped endo-functionalized anthracene-based cavities by introducing inward-directed pyridine units. The subtle modifications can significantly affect the binding properties of these receptors, which is similar to the mutations in biological systems. Combining theoretical calculations and molecular recognition experiments demonstrated that these “mutations” have an impact on the hydrophobicity and charge distribution of the hosts, consequently significantly influencing molecular *** is crucial for understanding the intricate mechanisms of molecular-level interactions in biological receptors.

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Can patients with mild non-neoplastic lesions diagnosed at baseline screening be safely exempt from surveillance: evidence from multicenter community-based cohorts

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Science China life Sciences 2025年第1期 263-271页

作者： Siyi He Zhiyi Zhang Guohui Song Zhenhai Wang Chunyun Dai Shipeng Yan Kun Jiang Bingbing Song He li Maomao Cao Dianqin Sun Fan Yang Xinxin Yan Shaoli Zhang yi Teng Qianru li Changfa Xia Wanqing Chen Office of Cancer Screening National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical College Department of Gastroenterology Gansu Wuwei Tumor Hospital Cixian Cancer Institute linzhou Cancer Hospital Center for Disease Control and Prevention of Sheyang County Department of Cancer Prevention and Control Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of MedicineCentral South University Luoshan Center for Disease Control and Prevention Office for Cancer Control and Research Affiliated Cancer Hospital of Harbin Medical University

Surveillance recommendations for gastric cancer（GC） in current guidelines focused on advanced precancerous lesions and were based on precise diagnosis of severity/extent of baseline lesions. We aimed to develop a less endoscopy-related equipment-dependent risk-stratification tool, and assessed whether mild-precursor-lesion patients can be safely exempt from surveillance. In the multicenter communitybased cohort, 75,051 participants receiving baseline endoscopy were enrolled during 2015–2017 and followed-up until 2021. Cumulative incidence rates（CIRs） of GC for precancerous-conditions were calculated by Kaplan-Meier method and compared by Log-rank tests. Mixedeffects Cox regression models were used to detect potential factors for progression towards GC. A risk score was calculated as counts of selected factors. An independent cohort, including 26,586 participants was used for external validation. During a median follow-up of 6.25 years, CIRs of GC were 0.302%, 0.436%, and 4.756% for normal group, non-neoplastic（atrophic gastritis/intestinal metaplasia） and neoplastic lesions（low-grade/high-grade dysplasia）, respectively(Ptrendlimited vegetable consumption, were selected for risk-stratification. High-risk patients（≥3 risk factors） with non-neoplastic lesions showed higher GC risks（adjusted HR=7.73, 95%CI: 4.29–13.92）, and their four-year CIR reached the one-year CIR of neoplastic lesions. Further categorizing non-neoplastic lesions by histological grade, both patients with moderate-to-severe lesions（aHR=3.07, 95%CI: 1.67–5.64） and high-risk patients with mild lesions（aHR=7.29, 95%CI: 3.58–14.86） showed higher risks. Consistent trends were observed in validation cohort. High-risk mild-precursor-lesion patients should receive surveillance within 3–5 years after baseline screening. Our study provides evidence on supplementing current guideline recommendations.

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Lunar cratering asymmetries with high lunar orbital obliquity and inclination of the Moon

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Research in Astronomy and Astrophysics 2021年第6期21卷 281-293页

作者： Hua-Cheng li Nan Zhang Zong-Yu Yue yi-zhuo Zhang Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing 100871China Earth Dynamics Research Group School of Earth and Planetary SciencesCurtin University6102 WAAustralia State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100101China

Accurate estimation of cratering asymmetry on the Moon is crucial for understanding Moon evolution *** studies of cratering asymmetry have omitted the contributions of high lunar obliquity and ***,we include lunar obliquity and inclination as new controlling variables to derive the cratering rate spatial variation as a function of longitude and *** examining the influence of lunar obliquity and inclination on the asteroids population encountered by the Moon,we then have derived general formulas of the cratering rate spatial variation based on the crater scaling *** formulas with addition of lunar obliquity and inclination can reproduce the lunar cratering rate asymmetry at the current Earth-Moon distance and predict the apex/ant-apex ratio and the pole/equator ratio of this lunar cratering rate to be 1.36 and 0.87,*** apex/ant-apex ratio is decreasing as the obliquity and inclination *** with the evolution of lunar obliquity and inclination,our model shows that the apex/ant-apex ratio does not monotonically decrease with Earth-Moon distance and hence the influences of obliquity and inclination are not negligible on evolution of apex/ant-apex *** model is generalizable to other planets and moons,especially for different spin-orbit resonances.

关键词： Moon meteorites meteors meteoroids planets and satellites:surfaces

Analysis of the anti-T2DM components in dichloromethane fraction of Schisandra sphenanthera and its mechanism

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Traditional Medicine Research 2025年第1期10卷 27-43页

作者： Shi-Bo Feng Hai-Hui Jiang Hui-li Kang yi Jiang Hua-Wei Zhang Xiao-Mei Song Yu-Ze li Wen-li Huang Dong-Dong Zhang Chong Deng School of Pharmacy Shaanxi University of Chinese MedicineXianyang 712046China School of Pharmacy and Shaanxi Qinling Application Development and Engineering Center of Chinese Herbal Medicine Shaanxi University of Chinese MedicineXianyang 712046China Key Laboratory for Research and Development of“Qin Medicine”of Shaanxi Administration of Traditional Chinese Medicine Xianyang 712046China Shaanxi Key Laboratory of Research and Application of“Taibai Qi Yao” Xianyang 712046China

Background:The type 2 diabetes mellitus(T2DM)pharmacodynamic study of various parts of Schisandra sphenanthera was conducted in the previous stage,and it was found that dichloromethane extracted part(SDP)had a significant hypoglycemic ***,the components of SDP were analyzed,and the specific mechanism of its anti-T2DM was ***:We used a high-fat,high-sugar diet in combination with streptozotocin to induce a T2DM rat model,and the model rats were divided into two groups according to body weight and blood ***,oral glucose tolerance test,fasting blood glucose,low density lipoprotein cholesterol,superoxide dismutase,insulin,glycated hemoglobin,total cholesterol,nonesterified free fatty acids,alanine aminotransferase,high-density lipoprotein cholesterol,aspartate aminotransferase,malondialdehyde,and glutathione peroxidase were measured,organ indices were calculated,and pathological sections of pancreas and liver were *** 16S rRNA V3–V4 region of intestinal flora was sequenced to explore the effect of SDP on biochemical indicators and intestinal *** on the above indicators,the anti-T2DM mechanism of SDP in Schisandra sphenanthera was ***:After six weeks of administration,the biochemical indices of diabetic rats were diminished compared to the control *** SDP could significantly increase the gut microbialα-diversity index,resulting in significant changes in the flora of T2DM rats,with increased richness and diversity,reduced harmful flora,and significantly back-regulated the levels of acetic acid,propionic acid,and butyric ***:SDP can improve the symptoms associated with elevated blood glucose,dyslipidemia,elevated fasting insulin levels,and damaged glucose tolerance in *** against T2DM may be through the control of intestinal flora to normalize and exert anti-diabetic effect;its main active components may be lignans and terpenoids.

关键词： Schisandra sphenanthera T2DM intestinal flora HPLC

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我国高中英语教材生态素养呈现研究

外语学刊 2025年第1期 57-63页

作者：李润怡张虹北京外国语大学中国外语与教育研究中心北京100089

本研究以7册我国高中英语教材作为研究对象,运用内容分析和生态话语分析方法,探究教材生态素养呈现及其话语表征。研究发现:教材中生态行为素养和生态知识素养的内容较多,生态伦理素养和生态情感素养的内容较少。各生态素养内容又有其... 详细信息

本研究以7册我国高中英语教材作为研究对象,运用内容分析和生态话语分析方法,探究教材生态素养呈现及其话语表征。研究发现:教材中生态行为素养和生态知识素养的内容较多,生态伦理素养和生态情感素养的内容较少。各生态素养内容又有其较为凸显的话语表征,包括:将专家作为言说主体、将自然标记为积极价值、将人与自然作为同类参与者角色、倡导保护自然的行动以及反思破坏自然的活动。基于研究发现,本研究从内容选择、话语建构、活动设计等方面为教材编写者和一线英语教师提供了建议。

关键词：生态知识素养生态情感素养生态伦理素养生态行为素养高中英语教材生态话语分析及物性

Influence of deformation path on the forming effect in a multistep flexible rolling process

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International Journal of Minerals,Metallurgy and Materials 2018年第10期25卷 1173-1180页

作者： ying li Wen-zhi Fu Ming-zhe li Xiao-dong liu Shuo Sun zhuo yi Roll Forging Institute Jilin University College of materials science and engineering Jilin University

The flexible rolling process(FRP) is a novel three-dimensional(3 D) forming process that combines the multipoint and traditional rolling forming. The principle of FRP is based on thickness thinning, so the deformation path significantly impacts the forming effect. In this study, the multistep forming process with different deformation paths was introduced to improve the forming effect of FRP. For instance, with the convex surface part, three finite element models of multistep FRP(MSFRP) were established. The corresponding numerical simulations and forming experiments performed among different deformation paths showed the surface part with a longer effective forming region was obtained and the forming regions with more steps in MSFRP were smoother. Thus, the sheet-metal utilization rate was greatly improved. Moreover, the MSFRP can improve the longitudinal bending effect dramatically and thereby endowing the forming part with a better forming effect. Therefore, MSFRP is a prospective method for broad applications.

关键词： 3D surface forming multistep flexible rolling numerical simulation deformation path forming effect

Integrated interface between composite electrolyte and cathode with low resistance enables ultra-long cycle-lifetime in solid-state lithium-metal batteries

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Science China Chemistry 2021年第4期64卷 673-680页

作者： zhuo li Xin Guo State Key Laboratory of Material Processing and Die&Mould Technology Laboratory of Solid State IonicsSchool of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

We report a three-dimensional(3D)nanofiber-reinforced solid composite electrolyte with a 3D li^(+)-conducting ceramic network of li_(6.2)5Ga_(0.25)La_(3)Zr_(2)O_(12)(LLZO)*** from the 3D structure,the composite shows a high ionic conductivity of 3.2×10^(-4)S cm^(-1)and li-ion transference number of 0.32 at room *** interfacial resistance between the composite solid electrolyte and cathode is mitigated by creating an integrated interfacial structure,in which the polyethylene oxide(PEO)-lithiumbis(trifluoromethylsulphonyl)imide(liTFSI)binder and ionic liquids(ILs)form a viscoelastic ***,intimate contact,low interfacial impedance,and fast ion-transport between the cathode and the solid electrolyte are simultaneously ***-state lithium metal batteries with the li Fe PO_(4) cathode deliver a superior capacity(158.0 m A h g^(-1))and significant capacity retention(90.4%retention after 800 cycles)at 60℃.Moreover,the smooth and uniform li surface after long-term cycling confirms the successful suppression of the dendrite *** integrated interfacial structure provides a solution to the interfacial problem and improves the cycling performance in solid-state li-metal batteries.

关键词： composite solid electrolyte li_(7)La_(3)Zr_(2)O_(12)nanofiber interfacial resistance solid-state battery

A new sampler for simulating aerosol deposition in the respiratory tract

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Nuclear Science and Techniques 2008年第3期19卷 169-173页

作者： li Dehong zhuo Weihai yi Yanling CHEN Bo liU Haikuan Institute of Radiation Medicine Fudan University Shanghai 200032 China

For estimation of the deposition fractions of radon progeny in different regions of the respiratory tract, a new sampler consisting of three different configurations of sampling heads was developed. The deposition fractions of aerosols on the wire screens inside the sampling heads were calculated with the fan model of filtration theory. The deposition fractions of aerosols in different regions of the respiratory tract were calculated with the lung dose evaluation program (LUDEP)developed by National Radiological Protection Board (NRPB) as references. In general indoor and mine environments, the deviation between the deposition fractions of attached aerosol on the wire screens designed in this study and its reference values in the respiratory tract is less than 5%. It is possible to accurately estimate the deposition fractions of radon progeny in different regions of the respiratory tract through mimic measurements of radon progeny collected with the new sampler.

关键词：放射性污染环境放射学气溶胶呼吸过程