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Advances in microfluidic-based DNA methylation analysis

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Nanotechnology and Precision Engineering 2024年第1期7卷 116-134页

作者： Jiwen Li Tiechuan Li Xuexin duan State Key Laboratory of Precision Measuring Technology and Instruments Tianjin UniversityTianjin 300072China

DNA methylation has been extensively investigated in recent years,not least because of its known relationship with various *** in analytical methods can greatly increase the relevance of DNA methylation studies to both clinical medicine and scientiﬁc ***ﬂu-idic chips are excellent carriers for molecular analysis,and their use can provide improvements from multiple ***-chip molecular analysis has received extensive attention owing to its advantages of portability,high throughput,low cost,and high efﬁ*** recent years,the use of novel microﬂuidic chips for DNA methylation analysis has been widely reported and has shown obvious superiority to conventional *** this review,weﬁrst focus on DNA methylation and its ***,we discuss advanced microﬂuidic-based methods for DNA methylation analysis and describe the great progress that has been made in recent ***,we summarize the advantages that microﬂuidic technology brings to DNA methylation analysis and describe several challenges and perspectives for on-chip DNA methylation *** review should help researchers improve their understanding and make progress in developing microﬂuidic-based methods for DNA methylation analysis.

关键词： Microﬂuidic chip DNA methylation analysis Molecular analysis High throughput Low cost

Low-Complexity Reconstruction of Covariance Matrix in Hybrid Uniform Circular Array

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China Communications 2024年第3期21卷 66-74页

作者： Fu Zihao Liu Yinsheng duan Hongtao Information School Communication University of ChinaBeijing 100024China Beijing Institute of Electronic System Engineering Beijing 100854China School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China Beijing Radio Monitoring Station of State Radio Monitoring Center(SRMC) Beijing 100037China

Spatial covariance matrix(SCM) is essential in many multi-antenna systems such as massive multiple-input multiple-output(MIMO). For multi-antenna systems operating at millimeter-wave bands, hybrid analog-digital structure has been widely adopted to reduce the cost of radio frequency *** this situation, signals received at the antennas are unavailable to the digital receiver, and as a consequence, traditional sample average approach cannot be used for SCM reconstruction in hybrid multi-antenna systems. To address this issue, beam sweeping algorithm(BSA) which can reconstruct the SCM effectively for a hybrid uniform linear array, has been proposed in our previous works. However, direct extension of BSA to a hybrid uniform circular array(UCA)will result in a huge computational burden. To this end, a low-complexity approach is proposed in this paper. By exploiting the symmetry features of SCM for the UCA, the number of unknowns can be reduced significantly and thus the complexity of reconstruction can be saved accordingly. Furthermore, an insightful analysis is also presented in this paper, showing that the reduction of the number of unknowns can also improve the accuracy of the reconstructed SCM. Simulation results are also shown to demonstrate the proposed approach.

关键词： hybrid array millimeter-wave spatial covariance matrix uniform circular array

Cloud Microphysical Characteristics of Typhoon Meranti(2016)during Its Rapid Intensification:Model Validation and SST Sensitivity Experiments

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Journal of Meteorological Research 2024年第3期38卷 542-557页

作者： Rui WANG Yihong duan jianing FENG Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai200438China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing100081China

Cloud microphysics plays an important role in determining the intensity and precipitation of tropical cyclones(TCs).In this study,a high-resolution numerical simulation by WRF(version 4.2)of Typhoon Meranti(2016)during its rapid intensification(RI)period was conducted and validated by multi-source observations including Cloud-Sat and Global Precipitation Mission satellite *** snow and ice particles content were found to increase most rapidly compared with other hydrometeors during the RI *** all hydrometeors continued to *** graupel content only increased in the initial RI stage,and then decreased afterwards due to precipitation during the RI *** addition,sea surface temperature(SST)sensitivity experiments showed that,although the intensity of the TC increased with a higher SST,not all hydrometeors *** graupel content continued to increase with the increase in SST,mainly due to the accumulation of more lower-temperature supercooled water vapor at the corresponding *** content of snow decreased with the increase in SST because stronger vertical motion at the corresponding height affected the aggregation of ice crystals.

关键词： tropical cyclone rapid intensification cloud microphysical characteristics sea surface temperature(SST)

GNN-based temporal knowledge reasoning for UAV mission planning systems

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The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 12-25页

作者： Chai Rong duan Xiaofang Wang Lixuan School of Communications and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China

Unmanned aerial vehicles(UAVs)are increasingly applied in various mission scenarios for their versatility,scalability and *** UAV mission planning systems(UMPSs),an efficient mission planning strategy is essential to meet the requirements of UAV ***,rapidly changing environments and unforeseen threats pose challenges to UMPSs,making efficient mission planning *** address these challenges,knowledge graph technology can be utilized to manage the complex relations and constraints among UAVs,missions,and *** paper investigates knowledge graph application in UMPSs,exploring its modeling,representation,and storage concepts and ***,the construction of a specialized knowledge graph for UMPS is ***,the paper delves into knowledge reasoning within UMPSs,emphasizing its significance in timely updates in the dynamic environment.A graph neural network(GNN)-based approach is proposed for knowledge reasoning,leveraging GNNs to capture structural information and accurately predict missing entities or relations in the knowledge *** relation reasoning,path information is also incorporated to improve the accuracy of *** account for the temporal dynamics of the environment in UMPS,the influence of timestamps is captured through the attention *** effectiveness and applicability of the proposed knowledge reasoning method are verified via simulations.

关键词： unmanned aerial vehicle mission planning knowledge graph knowledge reasoning graph neural network

High-order Autler–Townes splitting in electrically tunable photonic molecules

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Photonics Research 2024年第8期12卷 1794-1801页

作者： YIHAO CHEN JUNTAO duan JIN LI YAN CHEN JIEWEN LI jiaNAN duan XIAOCHUAN XU jiaWEI WANG School of Integrated Circuit Harbin Institute of Technology(Shenzhen) College of Advanced Interdisciplinary Studies National University of Defense Technology National Key Laboratory of Laser Spatial Information Harbin Institute of Technology(Shenzhen)

Whispering gallery mode optical microresonators represent a promising avenue for realizing optical analogs of coherent light–atom interactions, circumventing experimental complexities. All-optical analogs of Autler–Townes splitting have been widely demonstrated, harnessing coupled optical microresonators, also known as photonic molecules, wherein the strong coupling between resonant fields enables energy level splitting. Here, we report the characterizations of Autler–Townes splitting in waveguide-coupled microring dimers featuring mismatched *** exploiting backscattering-induced coupling via Rayleigh and Mie scatterers in individual rings, high-order Autler–Townes splitting has been realized, yielding supermode hybridization in a multi-level system. Upon resonance detuning using an integrated phase shifter, intra-cavity coupling-induced splitting becomes almost indistinguishable at the zero-detuning point where the strong inter-cavity coupling counteracts the imbalance of backscattering strengths in individual rings. Through demonstrations on the maturing silicon photonics platform, our findings establish a framework of electrically tunable photonic molecules for coupling-mediated Autler–Townes splitting, offering promising prospects for on-chip signal generation and processing across classical and quantum regimes.

关键词： Chemical vapor deposition Coupled mode theory Microcavities Resonant modes Silicon photonics Whispering gallery modes

Reinterpret the heterogeneous reaction of α-Fe_(2)O_(3) and NO_(2) with 2D-COS:The role of SDS,UV and SO_(2)

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Chinese Chemical Letters 2024年第6期35卷 469-473页

作者： Haojie duan Hejingying Niu Lina Gan Xiaodi duan Shuo Shi Li Li School of Environmental&Chemical Engineering Shanghai UniversityShanghai 200444China School of Environment and Architecture University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Aircraft Design and Research Institute Shanghai 201210China

Heterogeneous reaction of mineral aerosols and atmospheric polluting gases play an important role in atmospheric *** this study,the reactions of NO_(2) with or without SO_(2) mixture gas on the surface of α-Fe_(2)O_(3) particles under dry conditions were *** effects of sodium dodecyl sulfate(SDS)and the heterogeneous reaction under both dark and UV irradiation conditions were *** infrared spectrum analyzed by the two-dimensional correlation spectroscopy(2D-COS)was used to obtain the products formation *** results showed that UV irradiation can promote the production of *** 2D-COS analysis indicated SDS changed the sequence order of nitrate and nitrite species during *** oxidation conditions,the final product of heterogeneous reaction of NO_(2) and α-Fe_(2)O_(3) was monodentate *** the heterogenous reaction of NO_(2) and α-Fe_(2)O_(3) containing SDS(FOS)without UV light,the final product was bidentate *** was the catalysis agent supply and photoresist to the *** surface active compounds,the environmental lifetime of heterogeneous reactions between trace gases and aerosols ***,ultraviolet light,and the types of gases involved in the reaction all have complex effects on the aerosol aging *** study provided a reference for subsequent heterogeneous reaction studies and the formation of aerosols.

关键词： Heterogeneous reaction α-Fe_(2)O_(3) 2D-COS SDS Aerosol

P-symmetric Subharmonic Solutions for Nonlinear Hamiltonian Systems

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1388-1408页

作者： duan Zhi ZHANG Zhi Hao ZHAO School of Mathematical Sciences Nankai UniversityTianjin 300071P.R.China

In this paper,we prove that for each positive k≡1 mod m there exists a P-symmetric kmτ-periodic solution xk for asymptotically linear mτ-periodic Hamiltonian systems,which are nonautonomous and endowed with a *** the P-symmetric Hamiltonian function is semi-positive,one can prove,under a new iteration inequality of the Maslov-type P-index,that xk_(1) and xk_(2) are geometrically distinct for k_(1)/k_(2)≥(2n+1)m+1;and xk_(1),xk_(2) are geometrically distinct for k_(1)/k_(2)≥m+1 provided xk_(1) is non-degenerate.

关键词： P-symmetric subharmonic Hamiltonian systems Maslov-type index theory iteration inequality asymptotically linear

Unidirectional propagation of water waves near ancient Luoyang Bridge

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Frontiers of physics 2024年第3期19卷 167-174页

作者： Linkang Han Qilin duan Junliang duan Shan Zhu Shiming Chen Yuhang Yin Huanyang Chen Shenzhen Research Institute of Xiamen University Shenzhen 518000China Department of Physics Xiamen UniversityXiamen 361005China Key Laboratory of Underwater Acoustic Communication and Marine Information Technology of the Ministry of Education Xiamen UniversityXiamen 361005China

Metasurfaces and metagratings offer new platforms for electromagnetic wave control with significant ***,metasurfaces based on abrupt phase change and resonant structures suffer from the drawback of high loss and face challenges when applied in water ***,the application of metasurfaces in water wave control is not ideal due to the limitations associated with high loss and other *** have discovered that non-resonant metagratings exhibit promising effects in water wave *** the similarity between bridges and metagratings,we have successfully developed a water wave metagrating model inspired by the ancient Luoyang Bridge in *** conduct theoretical calculations and simulations on the metagrating and derive the equivalent anisotropic model of the *** model provides evidence that the metagrating has the capability to control water waves and achieve unidirectional surface water *** accuracy of our theory is strongly supported by the clear observation of the unidirectional propagation phenomenon during simulation and experiments conducted using a reduced version of the *** is the first time that the unidirectional propagation of water waves has been seen in water wave metagrating *** all,we realize the water wave metagrating experiment for the first *** combining complex gratings with real bridges,we explore the physics embedded in the ancient building—Luoyang Bridge,which are of great significance for the water wave metagrating design and provide a new method for analyzing the effects of water waves on *** the same time,this discovery also provides a new idea for ocean cargo transportation,ocean garbage cleaning,and the development and protection of ancient bridges.

关键词： Luoyang Bridge unidirectional propagation water wave metagratings equivalent anisotropic model

Joint Sample Position Based Noise Filtering and Mean Shift Clustering for Imbalanced Classification Learning

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Tsinghua Science and Technology 2024年第1期29卷 216-231页

作者： Lilong duan Wei Xue Jun Huang Xiao Zheng School of Computer Science and Technology Anhui University of TechnologyMaanshan 243032China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China

The problem of imbalanced data classification learning has received much *** classification algorithms are susceptible to data skew to favor majority samples and ignore minority *** weighted minority oversampling technique(MWMOTE)is an effective approach to solve this problem,however,it may suffer from the shortcomings of inadequate noise filtering and synthesizing the same samples as the original minority *** this end,we propose an improved MWMOTE method named joint sample position based noise filtering and mean shift clustering(SPMSC)to solve these ***,in order to effectively eliminate the effect of noisy samples,SPMsC uses a new noise filtering mechanism to determine whether a minority sample is noisy or not based on its position and distribution relative to the majority *** that MWMOTE may generate duplicate samples,we then employ the mean shift algorithm to cluster minority samples to reduce synthetic replicate ***,data cleaning is performed on the processed data to further eliminate class *** on extensive benchmark datasets demonstrate the effectiveness of SPMsC compared with other sampling methods.

关键词： imbalanced data classification oversampling noise filtering clustering