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Locally and globally uniform approximations for ruin probabilities of a nonstandard bidimensional risk model with subexponential claims

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 98-113页

作者： LIU Zai-ming GENG Bing-zhen wang Shi-jie School of Mathematics and Statistics Central South UniversityChangsha 410083China School of Big Data and Statistics Anhui UniversityHefei 230601China

Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair of the claim-inter-arrival times is arbitrarily *** some mild conditions,we achieve a locally uniform approximation of the finite-time ruin probability for all time horizon within a finite *** we further assume that each pair of the claim-inter-arrival times is negative quadrant dependent and the two classes of claims are consistently-varying-tailed,it shows that the above obtained approximation is also globally uniform for all time horizon within an infinite interval.

关键词： bidimensional risk model asymptotic formula subexponential distribution consistently varying tail ruin probability

Strengthening effect of prefabrication(10-12)tensile twinning on AZ80+0.4%Ce magnesium alloy and inhibition mechanism of discontinuous precipitation

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Journal of Magnesium and Alloys 2024年第5期12卷 1918-1930页

作者： zhen wang Xi Zhao Zhimin Zhang Yaojin Wu Kai Chen Xianwei Ren Dengkui wang Wei wang School of Mechanical and Electrical Engineering North University of ChinaTaiyuan 030051China Engineering Technology Research Center for Integrated Precision Forming of Shanxi Province North University of ChinaTaiyuan 030051China

This paper provided an effective method to further improve the mechanical properties of the AZ80+0.4%Ce magnesium alloy wheel *** effect of high strength and ductility was obtained with a yield strength of 295.36 MPa,an elongation of 10%,by the combination of pre-deformation(7%deformation)and two-stage aging treatment(120℃/9 h+175℃/24 h).The evolution of the microstructure and properties of the alloy was explored under the coupling conditions of different pre-deformation degrees and multi-stage *** results show that,pre-deformation introduced a large number of(1012)tensile twinning and dislocations,which greatly promoted the probability of continuous precipitates(CPs)*** the contrary,the discontinuous precipitates(DPs)were limited by the vertical and horizontal twin *** a result,the pre-nucleation method of two-stage aging increased the proportion of CPs by 34%-38%.Owing to the DPs was effectively suppressed,the alloy's yield strength has been greatly ***,under multi-stage aging,the twin boundaries induce protruding nucleation to form static recrystallization by hindering the migration of dislocations,and the matrix swallows the twins,then the texture gradually tilts from the two poles to the basal *** an important supplement,the grain refinement and oblique texture promoted the improvement of the yield strength of the component.

关键词： Magnesium alloy Pre-deformed Two-stage aging Tensile twinning Continuous precipitates Texture

Molecular Chaperone-Dependent Polymer Translocation through Nanopores: The Effects of Chaperone Concentration and Chaperone-Polymer Interaction

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Chinese Journal of Polymer Science 2024年第1期42卷 125-132,I0011页

作者： Chang-Sheng Zuo Kang wang Li-zhen sun Ting-Ting sun Department of Physics Zhejiang University of Science and TechnologyHangzhou 310023China Department of Applied Physics Zhejiang University of TechnologyHangzhou 310014China

The polymer translocation through a nanopore from a donor space(or named cis side) to a receiver space(trans side) in the chaperone-induced crowded environment has attracted increasing attention in recent years due to its significance in biological systems and technological applications. In this work, we mainly focus on the effects of chaperone concentration and chaperone-polymer interaction on the polymer translocation. By assuming the polymer translocation to be a quasi-equilibrium process, the free energy F of the polymer can be estimated by Rosenbluth-Rosenbluth method and then the translocation time τ can be calculated by Fokker-Plank equation based on the obtained free energy landscape. Our calculation results show that the translocation time can be controlled by independently tuning the chaperone concentration and chaperone-polymer interaction at the cis side or the trans side. There exists a critical chaperone-polymer attraction ε~*=-0.2 at which the volume exclusion and interaction effects of the chaperone can balance each other. Additionally, we also find that at large chaperone-polymer attraction, the translocation time is mainly governed by the diffusion coefficient of the polymer.

关键词： Polymer translocation Rosenbluth-Rosenbluth method Fokker-Plank equation Free energy landscapes

A novel model of the carbon cycle in the Cambrian ocean

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Science China Earth Sciences 2024年第6期67卷 1759-1778页

作者： Huajian wang Shuichang ZHANG Xiaomei wang Jin su Yuntao YE Yuke LIU Key Laboratory of Petroleum Geochemistry Research Institute of Petroleum Exploration and DevelopmentChina National Petroleum CorporationBeijing 100083China Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing 100871China

The classic model of the carbon cycle suggests that the extensive burial of ^(12)C-enriched organic carbon leads to a positive carbon isotope(δ^(13)C)excursion(CIE),while massive oxidation of organic carbon results in a negative ***,global events such as the BAsal Cambrian Carbon isotope Excursion(BACE)and the Steptoean Positive Carbon Isotope Excursion(SPICE)are global negative and positive δ^(13)C excursions,respectively,and they also exhibit significant organic carbon burial anomalies,displaying decoupling between carbon isotope anomalies and organic carbon *** on the analyses of the Cambrian carbon cycle and paleoceanographic evolution records from well Tadong2 in the Tarim Basin,we propose a novel model of the carbon cycle in the Cambrian ocean that incorporates oceanic dissolved organic carbon(DOC).Our findings are as follows.(1)The Cambrian ocean maintained substantial DOC reservoirs,which were regulated by ocean currents and paleo-redox conditions and exerted significant influence on the oceanic carbon cycle.(2)The oxidation of the oceanic DOC reservoirs during the early Cambrian led to the BACE and the Asian Phenomenon of the Cambrian petroleum systems,while the expansion of the oceanic DOC reservoirs during the SPICE resulted in a global positive δ^(13)C excursion and the absence of significant organic carbon burial.(3)The deep-basin sedimentary environment in the eastern depression of the Tarim Basin may have fostered the development of organic-rich black shales during the Furongian Series,corresponding to organic carbon burial during the SPICE and representing potential prospects for ultra-deep oil and gas *** research should focus on the formation mechanism,reserve scale,and influencing factors of the oceanic DOC reservoirs,as well as their resource and environmental *** is expected that new breakthroughs will be made in the fields of Earth system science and oil and gas exploration.

关键词： Carbon isotope Organic carbon BACE SPICE Dissolved organic carbon Climate change Black shale

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Cavity-enhanced photoacoustic dual-comb spectroscopy

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Light(Science & Applications) 2024年第4期13卷 610-618页

作者： zhen wang Qinxue Nie Haojia sun Qiang wang Simone Borri Paolo De Natale Wei Ren Department of Mechanical and Automation Engineering The Chinese University of Hong KongNew TerritoriesHong Kong SARChina. State Key Laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of Sciences130033 ChangchunChina. CNRINO-Istituto Nazionale di Ottica and LENS-European Laboratory for Nonlinear Spectroscopy50019 Sesto FiorentinoItaly

Photoacoustic dual-comb spectroscopy(DCS),converting spectral information in the optical frequency domain to the audio frequency domain via multi-heterodyne beating,enables background-free spectral measurements with high resolution and broad ***,the detection sensitivity remains limited due to the low power of individual comb lines and the lack of broadband acoustic ***,we develop cavity-enhanced photoacoustic DCS,which overcomes these limitations by using a high-finesse optical cavity for the power amplification of dual-frequency combs and a broadband acoustic resonator with a flat-top frequency *** demonstrate high-resolution spectroscopic measurements of trace amounts of C2H2,NH3 and CO in the entire telecommunications *** method shows a minimum detection limit of 0.6 ppb C2H2 at the measurement time of 100 s,corresponding to the noise equivalent absorption coefficient of 7×10−10 cm−*** proposed cavityenhanced photoacoustic DCS may open new avenues for ultrasensitive,high-resolution,and multi-species gas detection with widespread applications.

关键词： individual cavity spectroscopy

Magnetic-biased chiral molecules enabling highly oriented photovoltaic perovskites

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National Science Review 2024年第2期11卷 221-230页

作者： Jing Chen Caner Deger zhen-Huang su Kai-Li wang Guang-Peng Zhu Jun-Jie Wu Bing-Chen He Chun-Hao Chen Tao wang Xing-Yu Gao Ilhan Yavuz Yan-Hui Lou Zhao-Kui wang Liang-Sheng Liao Institute of Functional Nano&Soft Materials(FUNSOM) Laboratory of Advanced Negative Carbon TechnologiesSoochow University Department of Physics Marmara University Shanghai Synchrotron Radiation Facility(SSRF) Shanghai Advanced Research InstituteChinese Academy of Sciences College of Energy Soochow Institute for Energy and Materials Innovations Soochow University Macao Institute of Materials Science and Engineering Macau University of Science and Technology

The interaction between sites A, B and X with passivation molecules is restricted when the conventional passivation strategy is applied in perovskite（ABX3） photovoltaics. Fortunately, the revolving A-site presents an opportunity to strengthen this interaction by utilizing an external field. Herein, we propose a novel approach to achieving an ordered magnetic dipole moment, which is regulated by a magnetic field via the coupling effect between the chiral passivation molecule and the A-site（formamidine ion） in *** strategy can increase the molecular interaction energy by approximately four times and ensure a well-ordered molecular arrangement. The quality of the deposited perovskite film is significantly optimized with inhibited nonradiative recombination. It manages to reduce the open-circuit voltage loss of photovoltaic devices to 360 mV and increase the power conversion efficiency to 25.22%. This finding provides a new insight into the exploration of A-sites in perovskites and offers a novel route to improving the device performance of perovskite photovoltaics.

关键词： perovskite photovoltaics magnetic moment A-site regulation chiral molecules

A real-world study of the differences in Traditional Chinese Medicine diagnosis and treatment rules for coronavirus disease 2019 between Northern and Southern China

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Journal of Traditional Chinese Medicine 2024年第4期44卷 822-829页

作者： su Rui su Youzhu wang Shuo FAN Jie LIU Qingquan LIU Mifeng Department of infectious diseases Capital Medical University Beijing Hospital of Traditional Chinese Medicine

OBJECTIVE: To explore the differences in Traditional Chinese Medicine(TCM) diagnosis and treatment rules for coronavirus disease 2019(COVID-19) between Northern and Southern China based on the real-world data from 982 COVID-19 patients. METHODS: All consecutive cases of COVID-19 admitted to the TCM department of designated COVID-19 hospitals in eight provinces and cities were retrospectively analyzed. Patients were divided into a Northern and a Southern group according to the location of the admitting hospital. The symptoms, syndrome elements, syndrome distribution and herbal treatments were analyzed. The core prescriptions were extracted using the multiscale backbone-based network comparison algorithm(msbNC). REsuLTS: The distribution of syndrome elements showed that dampness was common in Northern and Southern China, wind and heat were more often present in the South, while fire toxin and spleen deficiency were more often encountered in the North. The distribution of syndromes showed that the South was dominated by heat dampness accumulating in the lung(55.69%), while the North was dominated by dampness-toxin stagnating in the lung(44.90%).The results of core prescription mining showed that dispelling dampness, dispersing wind, clearing heat and strengthening spleen were the common treatment methods in Northern and Southern China. For mild cases, Jinyinhua(Flos Lonicerae) and Lianqiao(Fructus Forsythiae suspensae) were often used in the South to clear heat and relieve exterior symptoms, while Chaihu(Radix Bupleuri Chinensis) and Huangqin(Radix Scutellariae Baicalensis) were often used in the North to relieve muscles by expelling heat. For moderate cases, Chaihu(Radix Bupleuri Chinensis), Qinghao(Herba Artemisiae Annuae), and Shigao(Gypsum Fibrosum) were often used to clear heat of Tri-jiao Channel and stomach in the South, while Fuling(Poria), Chenpi(Pericarpium Citri Reticulatae), and Dangshen(Radix Codonopsis) were often used to invigorate spleen and remove damp

关键词： COVID-19 North-South difference core prescription medicine, Chinese traditional retrospective studies syndrome

An overview of potential cardioprotective benefits of xanthophylls in atherosclerosis:an evidence-based review

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Food Science and Human Wellness 2024年第4期13卷 1739-1755页

作者： Yuting su Feng Chen Jiehua Chen Mingfu wang Shenzhen Key Laboratory of Marine Microbiome Engineering Institute for Advanced StudyShenzhen UniversityShenzhen 518060China Institution for Innovative Development of Food Industry Shenzhen UniversityShenzhen 518060China College of Civil and Transportation Engineering Shenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Food Nutrition and Health Shenzhen UniversityShenzhen 518060China

Atherosclerosis,as the most prevalent form of cardiovascular disease,is characterized by oxidized lowdensity lipoprotein(ox-LDL)accumulation in the vascular wall,increased inflammation of the large arteries,dysfunction of the endothelial cells(ECs)and vascular smooth muscle cells(VSMCs),which may eventually lead to the formation of ***,one of the main groups of carotenoids,have been proposed as preventive agents or adjunct therapies to prevent and slow the progression of atherosclerosis due to their cardioprotective ***,the underlying preventive mechanism of action of xanthophylls on the pathogenesis of atherosclerosis remains unclear,and clinical evidence of the effect of xanthophylls on atherosclerosis have not yet been summarized and critically *** this regard,we conducted a comprehensive literature search in four scientific databases(Pub Med,Google Scholar,Science Direct and Web of Science)and carefully analyzed the existing evidence to provide meaningful insights on the association between xanthophylls and atherosclerosis from various *** on the evidence from in vitro and in vivo studies,we explored several potential mechanisms,including antioxidant effect,anti-inflammatory effect,regulation of lipid metabolism,and modulation of ECs and VSMCs dysfunction,and we found that a clear picture of regulatory pathways of xanthophylls on atherosclerosis prevention and treatment is still *** addition,epidemiological studies suggested the possible relationship among high dietary intake of xanthophylls,high plasma/serum xanthophylls and a reduced risk of *** evidence from interventional studies investigating the effect of xanthophylls on atherosclerosis is very sparse,whilst indirect clinical evidence was only limited to astaxanthin and ***,well-designed long-term randomized controlled trials(RCTs)are highly recommended for future studies to investigate the effective dose of different

关键词： Atherosclerosis Xanthophylls Antioxidant Anti-inflammation Lipid metabolism

What induced the trend shift of mixed-layer depths in the Antarctic Circumpolar Current region in the mid-1980s?

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Acta Oceanologica Sinica 2024年第1期43卷 11-21页

作者： Shan Liu Jingzhi su Huijun wang Cuijuan sui Key Laboratory of Marine Hazards Forecasting National Marine Environmental Forecasting CenterMinistry of Natural ResourcesBeijing 100081China Center for Earth System Modeling and Prediction of CMA Beijing 100081China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China Nansen-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

An obvious trend shift in the annual mean and winter mixed layer depth(MLD)in the Antarctic Circumpolar Current(ACC)region was detected during the 1960–2021 *** trends stopped in mid-1980s,followed by a period of weak *** MLD deepening trend difference between the two periods were mainly distributed in the western areas in the Drake Passage,the areas north to Victoria Land and Wilkes Land,and the central parts of the South Indian *** newly formed ocean current shear due to the meridional shift of the ACC flow axis between the two periods is the dominant driver for the MLD trends shift distributed in the western areas in the Drake Passage and the central parts of the South Indian *** saltier trends in the regions north to Victoria Land and Wilkes Land could be responsible for the strengthening mixing processes in this region.

关键词： mixed layer depth trend shift Antarctic Circumpolar Current(ACC) flow axis