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Dynamical complexity of Anosov systems driven by a quasi-periodic force

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Science China Mathematics 2025年第1期68卷 89-136页

作者： wen Huang zeng Lian Kening Lu Department of Mathematics University of Science and Technology of ChinaHefei 230026China School of Mathematics Sichuan UniversityChengdu 610065China

Consider C^(2)Anosov systems on a compact manifold driven by a quasi-periodic *** study their dynamical complexity on various levels from the perspectives of both path-wise dynamics and stochastic *** that these systems are non-wandering(i.e.,every point in the phase space is nonwandering),we prove a set of results:(1)the existence of abundance of random periodic points;(2)a random Livsic theorem;(3)a random Mañé-Bousch-Conze-Guivarc'h lemma;(4)the existence of strong random ***,a concrete example constructed on a 2-dimensional torus is also given to uncover some interesting phenomena of the systems.

关键词： random Anosov systems Anosov system on bers entropy random periodic orbit random horseshoe cohomological equation random Livsic theorem random Bousch-Mañécohomology lemma

Experimental Study on Geometry Characteristics of Turbulent Premixed Flames for Natural Gas/Air Mixtures

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Journal of Thermal Science 2025年第1期34卷 268-282页

作者： ZHENG Weilin WANG Qijiao XIAO Huahua CHEN Xiaoxiao XIE Fan zeng wen Liaoning Key Lab of Advanced Test Technology for Aerospace Propulsion System Shenyang Aerospace UniversityShenyang 110136China State Key Laboratory of Fire Science University of science and Technology of ChinaHefei 230027China AVIC Shenyang Aircraft Design and Research Institute Shenyang 110035China

In this study,focusing on the geometry characteristics of spherical expanding flame,the turbulent premixed flames of natural gas/air mixtures were investigated in a fan-stirred turbulent *** effects of initial temperature(T=300-400 K),initial pressure(P=0.1-0.3 MPa),turbulence intensity(u'=1.0-2.7 m/s),oxygen volumetric percentage(φ(O_(2))=15%-21%)and carbon dioxide volumetric percentage(φ(CO_(2))=0-20%)were delved *** flame profile under the Cartesian coordinate system was derived from the schlieren images taken by the high-speed ***,from both macroscopic and microscopic perspectives,the influence of experimental conditions on the flame geometry characteristics was explored through flame front extraction,wavelet decomposition and network *** results demonstrate that for significant flame wrinkling,changes in species concentrations and turbulence intensity have more pronounced effects on the flame wrinkling *** wrinkling of the flame front maintains a certain degree of similarity,as evidenced by the locally concentrated distribution of the angles of the maximum fluctuation *** disturbance energy under large-scale(D6-D8)disturbances exhibits relatively high values with a similar trend,exerting a significant impact on the geometry characteristics of the flame *** peaks of correlation degree are scattered either with the decomposition scale or the development of flame radius,indicating no linear correlation between different detail ***,the probability distribution of node degrees in key wrinkled regions exhibits different trends with that of large-scale wrinkling and disturbance energy,especially with changes in initial *** occurs because the number of key wrinkles varies based on the perturbation's strength or the region's ***,an increase in the fluctuation frequency of the flame's local radius may not necessarily lead to an increase in the number of key folded regions.

关键词： geometry characteristics large-scale wrinkling wavelet decomposition network topology fan-stirred turbulent combustor

Construction and application of multicomponent fluorescent droplets

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Chinese Chemical Letters 2025年第1期36卷 137-146页

作者： Wei-Tao Dou Qing-wen zeng Yan Kang Haidong Jia Yulian Niu Jinglong Wang Lin Xu Shanghai Key Laboratory of Green Chemistry and Chemical Processes Shanghai Frontiers Science Center of Molecule Intelligent SynthesesSchool of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China Shanghai Jahwa United Co. Ltd.Shanghai 200082China Chongqing Key Laboratory of Precision Optics Chongqing Institute of East China Normal UniversityChongqing 401120China

The rapid development of microfluidic technology has led to the evolution of microdroplets from simple emulsion structures to complex multilayered and multicompartmental *** advancements have endowed microdroplets with the capability to contain multiple compartments that remain isolated from one another,enabling them to carry different molecules of ***,researchers can now investigate intricate spatially confined chemical reactions and signal transduction pathways within subcellular ***,modern microdroplets often possess excellent optical transparency,allowing fluorescently labelled,multi-layered,and compartmental droplets to provide detailed insights through real-time,in situ,and dynamic fluorescence ***,this review systematically summarizes current methodologies for preparing multicomponent microdroplets and their applications,particularly focusing on fluorescent ***,it discusses existing critical challenges and outlines future research *** offering a comprehensive overview of the preparation methods and applications of fluorescent microdroplets,this review aims to stimulate the interest of researchers and foster their utilization in more complex and biomimetic environments.

关键词： Fluorescent Microfluidic Fluorescent droplets Multilayered droplets Multicompartmental droplets

Prognostic roles nutritional index in patients with resectable and advanced biliary tract cancers

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World Journal of Gastroenterology 2025年第6期31卷 76-88页

作者： Di zeng Ning-Yuan wen Yao-Qun Wang Nan-Sheng Cheng Bei Li Division of Biliary Surgery Department of General SurgeryWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Research Center for Biliary Diseases West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Biliary tract cancer(BTC)is a rare,aggressive malignancy with increasing inci-dence and poor *** preoperative prognostic factors is crucial for effective risk-benefit assessments and patient *** prognostic nutritional index(PNI),which reflects immune-inflammatory and nutritional status,has shown prognostic value in various cancers,but its significance in BTC remains *** To assess the prognostic value of the preoperative PNI in BTC patients,with a focus on overall survival(OS)and disease-free survival(DFS).METHODS Comprehensive searches were conducted in the PubMed,EMBASE,and Web of Science databases from inception to April *** primary outcomes of interest focused on the associations between the preoperative PNI and the prognosis of BTC patients,specifically OS and disease-free survival(DFS).Statistical analyses were conducted via STATA 17.0 *** Seventeen studies encompassing 4645 patients met the inclusion ***-analysis revealed that a low PNI was significantly associated with poorer OS[hazard ratio(HR)1.91,95%CI:1.59-2.29;P<0.001]and DFS(HR 1.93,95%CI:1.39-2.67;P<0.001).Subgroup analyses revealed consistent results across BTC subtypes(cholangiocarcinoma and gallbladder cancer)and stages(resectable and advanced).Sensitivity analyses confirmed the robustness of these findings,and no significant publication bias was *** This study demonstrated that a low preoperative PNI predicts poor OS and DFS in BTC patients,highlighting its potential as a valuable prognostic *** prospective studies are needed to validate these findings and enhance BTC patient management.

关键词： Biliary tract cancer Prognostic nutritional index Predictive marker Meta-analysis Survival outcomes

Preparation of hierarchical MoS_(2)microsphere/BN composites for microwave absorption and thermal management

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International Journal of Minerals,Metallurgy and Materials 2025年第3期32卷 718-727页

作者： Haoliang wen Weidong Zhang College of Chemical Engineering Qinghai UniversityXining 810016China

The increase in the utilization of infrared heat detection technology in military applications necessitates research on composites with improved thermal transmission performance and microwave absorption *** study satisfactorily fabricated a series of MoS_(2)/BN-xyz composites(which were characterized by the weight ratio of MoS_(2)to BN,denoted by xy:z)through chemical vapor depos-ition,which resulted in their improved thermal stability and thermal transmission *** results show that the remaining mass of MoS_(2)/BN-101 was as high as 69.25wt%at 800℃under air atmosphere,and a temperature difference of 31.7℃was maintained between the surface temperature and the heating source at a heating temperature of 200℃.Furthermore,MoS_(2)/BN-301 exhibited an im-pressive minimum reflection loss value of-32.21 dB at 4.0 mm and a wide effective attenuation bandwidth ranging from 9.32 to 18.00 GHz(8.68 GHz).Therefore,these simplified synthesized MoS_(2)/BN-xyz composites demonstrate great potential as highly efficient con-tenders for the enhancement of microwave absorption performance and thermal conductance.

关键词： microwave absorbers thermal transmission hierarchical molybdenum disulfide microsphere boron nitride nanosheets

A nuclide identification method ofγspectrum and model building based on the transformer

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Nuclear Science and Techniques 2025年第1期36卷 80-93页

作者： Fei Li Chu-Yang Luo Ying-Zi wen Sheng Lv Feng Cheng Guo-Qiang zeng Jian-Feng Jiang Bing-Hai Li College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610000China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province Chengdu 610000China Department of Physics Universitat Politècnica de CatalunyaBarcelona 08028Spain Airborne Survey and Remote Sensing Center of Nuclear Industry Shijiazhuang 050000China Hebei Key Laboratory of Airborne Detection and Remote Sensing Technology Shijiazhuang 050000China

In current neural network algorithms for nuclide identification in high-background,poor-resolution detectors,traditional network paradigms including back-propagation networks,convolutional neural networks,recurrent neural networks,etc.,have been limited in research on γ spectrum analysis because of their inherent mathematical *** is difficult to make progress in terms of training data requirements and prediction *** contrast to traditional network paradigms,network models based on the transformer structure have the characteristics of parallel computing,position encoding,and deep stacking,which have enabled good performance in natural language processing tasks in recent ***,in this paper,a transformer-based neural network (TBNN) model is proposed to achieve nuclide identification for the first ***,the Geant4 program was used to generate the basic single-nuclide energy spectrum through Monte Carlo simulations.A multi-nuclide energy spectrum database was established for neural network training using random matrices of γ-ray energy,activity,and *** on the encoder–decoder structure,a network topology based on the transformer was built,transforming the 1024-channel energy spectrum data into a 32×32 energy spectrum sequence as the model *** experiments and adjustments of model parameters,including the learning rate of the TBNN model,number of attention heads,and number of network stacking layers,the overall recognition rate reached 98.7%.Additionally,this database was used for training AI models such as back-propagation networks,convolutional neural networks,residual networks,and long shortterm memory neural networks,with overall recognition rates of 92.8%,95.3%,96.3%,and 96.6%,*** indicates that the TBNN model exhibited better nuclide identification among these AI models,providing an important reference and theoretical basis for the practical application of transformers in the qualitative and quantitativ

关键词： Nuclide identification Neural network Transformer

Mesospheric tide comparisons at low latitudes observed by two collocated meteor radars

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Earth and Planetary Physics 2025年第1期9卷 54-68页

作者： Jian Li wen Yi XiangHui Xue Jie zeng HaiLun Ye JianYuan Wang JinSong Chen Na Li TingDi Chen Chinese Academy of Sciences(CAS)Key Laboratory of Geospace Environment Department of Geophysics and Planetary SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology Anhui Mengcheng Geophysics National Observation and Research StationUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China Yunnan Kunming Electromagnetic Environment National Observation and Research Station Qujing Kunming 655000China

Accurate knowledge of mesospheric winds and waves is essential for studying the dynamics and climate in the mesosphere and lower thermosphere(MLT)*** this study,we conduct a comparative analysis of the mesosphere tidal results obtained from two adjacent meteor radars at low latitudes in Kunming,China,from November 2013 to December *** two radars operate at different frequencies of 37.5 MHz and 53.1 MHz,***,overall good agreement is observed between the two radars in terms of horizontal winds and tide *** results show that the dominant tidal waves of the zonal and meridional winds are diurnal and semidiurnal ***,we conduct an exhaustive statistical analysis to compare the tidal amplitudes and vertical wavelengths recorded by the dual radar systems,which reveals a high degree of alignment in tidal *** investigation includes variances and covariances of tidal amplitudes,which demonstrate remarkable consistency across measurements from both *** finding highlights clear uniformity in the mesospheric tidal patterns observed at low latitudes by the two neighboring meteor *** of the comparative analysis specifically underscore the significant correlation in vertical wavelength measurements,validating the robustness of radar observations for tidal research.

关键词： mesosphere and lower thermosphere region meteor radar mesospheric winds tides

Quantum metrology with optimal control under an arbitrary non-Markovian bosonic environment

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Communications in Theoretical Physics 2025年第2期77卷 112-120页

作者： Likun Zhou wen Yang Beijing Computational Science Research Center

Finding the optimal control is of importance to quantum metrology under a noisy *** this paper, we tackle the problem of finding the optimal control to enhance the performance of quantum metrology under an arbitrary non-Markovian bosonic environment. By introducing an equivalent pseudomode model, the non-Markovian dynamic evolution is reduced to a Lindblad master equation, which helps us to calculate the gradient of quantum Fisher information and perform the gradient ascent algorithm to find the optimal control. Our approach is accurate and circumvents the need for the Born–Markovian approximation. As an example, we consider the frequency estimation of a spin with pure dephasing under two types of non-Markovian environments. By maximizing the quantum Fisher information at a fixed evolution time, we obtain the optimal multi-axis control, which results in a notable enhancement in quantum metrology. The advantage of our method lies in its applicability to the arbitrary non-Markovian bosonic environment.

关键词： quantum metrology non-Markovian environment optimal control

The potential mechanism and clinical application value of remote ischemic conditioning in stroke

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Neural Regeneration Research 2025年第6期20卷 1613-1627页

作者： Yajun Zhu Xiaoguo Li Xingwei Lei Liuyang Tang Daochen wen Bo zeng Xiaofeng Zhang Zichao Huang Zongduo Guo The First Affiliated Hospital of Chongqing Medical University ChongqingChina

Some studies have confirmed the neuroprotective effect of remote ischemic conditioning against stroke. Although numerous animal researches have shown that the neuroprotective effect of remote ischemic conditioning may be related to neuroinflammation, cellular immunity, apoptosis, and autophagy, the exact underlying molecular mechanisms are unclear. This review summarizes the current status of different types of remote ischemic conditioning methods in animal and clinical studies and analyzes their commonalities and differences in neuroprotective mechanisms and signaling pathways. Remote ischemic conditioning has emerged as a potential therapeutic approach for improving stroke-induced brain injury owing to its simplicity, non-invasiveness, safety, and patient tolerability. Different forms of remote ischemic conditioning exhibit distinct intervention patterns, timing, and application range. Mechanistically, remote ischemic conditioning can exert neuroprotective effects by activating the Notch1/phosphatidylinositol 3-kinase/Akt signaling pathway, improving cerebral perfusion, suppressing neuroinflammation, inhibiting cell apoptosis, activating autophagy, and promoting neural regeneration. While remote ischemic conditioning has shown potential in improving stroke outcomes, its full clinical translation has not yet been achieved.

关键词： Akt apoptosis autophagy cerebral perfusion cerebral vascular stenosis clinical transformation hemorrhagic stroke ischemic stroke neuroinflammation neuroprotection Notch1 PI3K remote ischemic conditioning stroke