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Communications in Computational Physics 2023年第5期33卷 1509-1513页

作者： Lulu Zhang Wei Cai zhi-qin john xu Institute of Natural Sciences and School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai200240China Department of Mathematics Southern Methodist UniversityDallasTX 75275USA

This note provides a correction of a missing weight constant in the MscaleDNN formula and some comments on the performance of the corrected algorithm.

关键词： Multi-scale DNN PDE solver deep learning

A Linear Frequency Principle Model to Understand the Absence of Overfitting in Neural Networks

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Chinese Physics Letters 2021年第3期38卷 121-126页

作者： Yaoyu Zhang Tao Luo Zheng Ma zhi-qin john xu School of Mathematical Sciences Institute of Natural SciencesMOE-LSCand Qing Yuan Research InstituteShanghai Jiao Tong UniversityShanghai 200240China Shanghai Center for Brain Science and Brain-Inspired Technology Shanghai 200031China

Why heavily parameterized neural networks(NNs) do not overfit the data is an important long standing open question. We propose a phenomenological model of the NN training to explain this non-overfitting puzzle. Our linear frequency principle(LFP) model accounts for a key dynamical feature of NNs: they learn low frequencies first, irrespective of microscopic details. Theory based on our LFP model shows that low frequency dominance of target functions is the key condition for the non-overfitting of NNs and is verified by experiments. Furthermore,through an ideal two-layer NN, we unravel how detailed microscopic NN training dynamics statistically gives rise to an LFP model with quantitative prediction power.

关键词： networks neural details

MOD-Net:A Machine Learning Approach via Model-Operator-Data Network for Solving PDEs

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Communications in Computational Physics 2022年第7期32卷 299-335页

作者： Lulu Zhang Tao Luo Yaoyu Zhang Weinan E zhi-qin john xu Zheng Ma Institute of Natural Sciences and School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai200240China School of Mathematical Sciences and Institute of Natural Sciences Shanghai Jiao Tong UniversityCMA-ShanghaiShanghai200240China MOE-LSC and qing Yuan Research Institute Shanghai Jiao Tong UniversityShanghai200240China Shanghai Center for Brain Science and Brain-Inspired Technology Shanghai200031China School of Mathematical Sciences Peking UniversityBeijing100871China AI for Science Institute Beijing100080China

In this paper,we propose a machine learning approach via model-operatordata network(MOD-Net)for solving PDEs.A MOD-Net is driven by a model to solve PDEs based on operator representationwith regularization *** linear PDEs,we use a DNN to parameterize the Green’s function and obtain the neural operator to approximate the solution according to the Green’s *** train the DNN,the empirical risk consists of the mean squared loss with the least square formulation or the variational formulation of the governing equation and boundary *** complicated problems,the empirical risk also includes a fewlabels,which are computed on coarse grid points with cheap computation cost and significantly improves the model ***,the labeled dataset works as a regularization in addition to the model *** MOD-Net solves a family of PDEs rather than a specific one and is much more efficient than original neural operator because few expensive labels are *** numerically show MOD-Net is very efficient in solving Poisson equation and one-dimensional radiative transfer *** nonlinear PDEs,the nonlinear MOD-Net can be similarly used as an ansatz for solving nonlinear PDEs,exemplified by solving several nonlinear PDE problems,such as the Burgers equation.

关键词： Deep neural network radiative transfer equation Green’s method neural operator

Association between Per and Polyfluoroalkyl Substance and Abdominal Fat Distribution:A Trait Spectrum Exposure Pattern and Structure-Based Investigation

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Biomedical and Environmental Sciences 2025年第1期38卷 3-14页

作者： zhi Li Shilin Shan Chenyang Song Chengzhe Tao Hong Qian qin Yuan Yan Zhang Qiaoqiao xu Yufeng qin Yun Fan Chuncheng Lu State Key Laboratory of Reproductive Medicine Center for Global HealthSchool of Public HealthNanjing Medical UniversityNanjing 211166JiangsuChina Key Laboratory of Modern Toxicology of Ministry of Education School of Public HealthNanjing Medical UniversityNanjing 211166JiangsuChina Department of Public Health Kangda College of Nanjing Medical UniversityLianyungang 222000JiangsuChina Department of Microbes and Infection School of Public HealthNanjing Medical UniversityNanjing 211166JiangsuChina

Objective To investigate the associations between eight serum per-and polyfluoroalkyl substances(PFASs)and regional fat depots,we analyzed the data from the National Health and Nutrition Examination Survey(NHANES)2011-2018 *** Multiple linear regression models were developed to explore the associations between serum PFAS concentrations and six fat compositions along with a fat distribution score created by summing the concentrations of the six fat *** associations between structurally grouped PFASs and fat distribution were assessed,and a prediction model was developed to estimate the ability of PFAS exposure to predict obesity *** Among females aged 39-59 years,trunk fat mass was positively associated with perfluorooctane sulfonate(PFOS).Higher concentrations of PFOS,perfluorohexane sulfonate(PFHxS),perfluorodecanoate(PFDeA),perfluorononanoate(PFNA),and n-perfluorooctanoate(n-PFOA)were linked to greater visceral adipose tissue in this *** men,exposure to total perfluoroalkane sulfonates(PFSAs)and long-chain PFSAs was associated with reductions in abdominal fat,while higher abdominal fat in women aged 39-59 years was associated with short-chain *** prediction model demonstrated high accuracy,with an area under the curve(AUC)of 0.9925 for predicting obesity *** PFAS exposure is associated with regional fat distribution,with varying effects based on age,sex,and PFAS *** findings highlight the potential role of PFAS exposure in influencing fat depots and obesity risk,with significant implications for public *** prediction model provides a highly accurate tool for assessing obesity risk related to PFAS exposure.

关键词： Per-and polyfluoroalkyl substances Regional fat depots Obesity Structure-based NHANES

Zwitterionic hyaluronic acid derivatives for co-delivery of both chemotherapeutic and nucleic acid drugs in breast cancer treatment

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Nano Research 2025年第1期18卷 607-617页

作者： Ruo-Lin Jiang Hui-Na Liu Yu-Fan Yang zhi-Cheng Zhang Qi Dai Xiao-Yan Bao Lin-Jie Wu Ya-Xin qin Xin Tan Xiao-Yan Sun xu-Fang Ying zhi-qing Ben Min Han Institute of Pharmaceutics College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China Department of Radiation Oncology Key Laboratory of Cancer Prevention and InterventionThe Second Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhou 310058China Hangzhou Institute of Innovative Medicine Zhejiang UniversityHangzhou 310058China Jinhua Institute of Zhejiang University Jinhua 321299China National Key Laboratory of Advanced Drug Delivery and Release Systems Zhejiang UniversityHangzhou 310058China Polytechnic institute Zhejiang UniversityHangzhou 310015China

Traditionally,hyaluronic acid has been widely used for drug delivery,but the current application bottleneck is that hyaluronic acid is hydrophilic and electronegative,which makes it difficult to carry hydrophobic drugs and small interfering RNA(siRNA)with the same *** on previous studies,we designed and synthesized hyaluronic acid nanocarriers HA-spermine/N,N,N-trimethylcystamine/DOX-TPP(HSTD)for loading siRNA to overcome the problem of siRNA release caused by strong electrostatic ***,N,N,Ntrimethylcystamine in the carrier can be degraded by intracellular glutathione to completely and rapidly release siRNA,thus promoting ***,when codelivered with the chemotherapy drug doxorubicin(DOX),this novel nanocarrier showed promising synergy in inhibiting tumor growth.

关键词： zwitterionic hyaluronic acid N N N-trimethylcystamine small interfering RNA(siRNA) doxorubicin

Precise spectroscopy of metastable Li plus using the optical Ramsey technique in support of time dilation tests

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PHOTONICS RESEARCH 2025年第1期13卷 201-209页

作者： Zhou, Peng-peng Chen, Shao-long qin, Cheng-gang Chang, xu-rui Zhou, zhi-qiang Sun, Wei Huang, Yao Gao, Ke-lin Guan, Hua Chinese Acad Sci Innovat Acad Precis Measurement Sci & Technol State Key Lab Magnet Resonance & Atom & Mol Phys Wuhan 430071 Peoples R China Informat Engn Univ Zhengzhou 450001 Peoples R China Chinese Acad Sci Key Lab Time Reference & Applicat Wuhan 430206 Peoples R China Huazhong Univ Sci & Technol MOE Key Lab Fundamental Phys Quant Measurement Wuhan 430074 Peoples R China Huazhong Univ Sci & Technol Hubei Key Lab Gravitat & Quantum Phys PGMF Wuhan 430074 Peoples R China Huazhong Univ Sci & Technol Sch Phys Wuhan 430074 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Chinese Acad Sci Qinghai Inst Salt Lakes Key Lab Green & High end Utilizat Salt Lake Resour Xining 810008 Peoples R China Wuhan Inst Quantum Technol Wuhan 430206 Peoples R China

Time dilation constitutes a crucial aspect of Lorentz invariance within special relativity and undergoes constant scrutiny through numerous Ives-Stilwell-type experiments employing the Doppler effect. In our study, we employed optical Ramsey spectroscopy on a Li+ ion beam to enhance the precision of measuring the intrinsic transition frequency 23S1 - 23P2 to the level of four parts in 1010 with speed of 0.00035c. Our findings reconciled an existing 2 MHz disparity between collinear and perpendicular laser spectroscopy. Furthermore, in conjunction with previous studies on Li+ ion beams traveling at speeds of 0.064c and 0.338c [Nat. Phys. 3, 861 (2007);Phys. Rev. Lett. 113, 120405 (2014)], we updated the Robertson-Mansouri-Sexl parameter alpha to be (-10.0 f 9.9) x 10-8 and (-2.9 f 2.0) x 10-8, respectively. (c) 2024 Chinese Laser Press

关键词： Doppler effect Frequency combs Laser beams Nodal aberration theory Optical clocks Optical fields

A telomere-to-telomere genome assembly of the cultivated peanut

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Molecular Plant 2025年第1期18卷 5-8页

作者： Xiaobo Wang Ziqi Sun Feiyan Qi zhiyuan Zhou Pei Du Lei Shi Wenzhao Dong Bingyan Huang Suoyi Han Stefano Pavan Meng Zhang Mengjie Cui Jing xu Hua Liu Li qin Zhongxin Zhang Xiaodong Dai Wei Gao Lijuan Miao Ruifang Zhao Juan Wang Mengmeng Wang Chenyang zhi Yaojun Hu Huanhuan Zhao Linjie Chen Xiaodong Jin Yanhui Sun Zheng Zheng Xinyou Zhang The Shennong Laboratory Zhengzhou 450002China Institute of Crop Molecular Breeding Henan Academy of Agricultural SciencesZhengzhou 450002China Henan Provincial Key Laboratory for Genetic Improvement of Oil Crops Zhengzhou 450002China National Innovation Centre for Bio-breeding Industry Xinxiang 453000China Department of Soil Plant and Food SciencesUniversity of Bari Aldo MoroBari 70126Italy

Dear Editor,Cultivated peanut(peanut in short)(Arachis hypogaea,2n=4x=40,genome type AABB)is a legume crop serving globally as a crucial source of edible oil and *** peanut reference genome sequences obtained for the cultivars"Tifrunner,""Shitouqi,"and"Fuhuasheng"were assembled or patched using third-generation sequencing technologies and significantly contributed to advancements in peanut genetics and breeding(Bertioli et al.,2019;Chen et al.,2019;Zhuang et al.,2019).However,unresolved gaps persist in these assemblies,particularly in regions of biological importance such as centromeres and telomeres(Supplemental Figure 1),hindering comprehensive exploration of their functional and evolutionary significance.

关键词： breeding cultivar Figure

Observation and mechanism of non-uniform distribution of tin nuclei in preparing vapor diffusion coated Nb_(3)Sn thin film for SRF applications

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Nuclear Science and Techniques 2025年第1期36卷 22-34页

作者： Shuai Wu Yang Ye Zi-qin Yang Yuan He Jian-Peng Li Guang-Ze Jiang Lu Li Shi-Chun Huang An-Dong Wu Hang-xu Li Shao-Hua Lu Tao Liu Feng Qiu Cang-Long Wang Ji-Zheng Duan Teng Tan zhi-Jun Wang Sheng-Hu Zhang Hong-Wei Zhao Wen-Long Zhan Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516007China School of Microelectronics Dalian University of TechnologyDalian 116000China

Growth of high-quality Nb_(3)Sn thin films for superconducting radiofrequency(SRF)applications using the vapor diffusion method requires a uniform distribution of tin nuclei on the niobium(Nb)*** study examines the mechanism underlying the observed non-uniform distribution of tin nuclei with tin chloride SnCl_(2).Electron backscatter diffraction(EBSD)analysis was used to examine the correlation between the nucleation behavior and orientation of niobium grains in the *** findings of the density functional theory(DFT)simulation are in good agreement with the experimental results,showing that the non-uniform distribution of tin nuclei is the result of the adsorption energy of SnCl_(2)molecules by varied niobium grain *** analysis indicated that the surface roughness and grain size of niobium also played significant roles in the nucleation *** study provides valuable insights into enhancing the surface pretreatment of niobium substrates during the growth of Nb_(3)Sn thin films using the vapor diffusion method.

关键词： Nucleation Tin chloride Non-uniform distribution Vapor diffusion Crystal orientation Adsorption energy

Random Group Recommendation Model Based on Fuzzy Clustering

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Journal of Electronic Science and Technology 2020年第2期18卷 169-178页

作者： Zhe Ding Zhen qin Qi-xu Wang zhi-Guang qin School of Information and Software Engineering University of Electronic Science and Technology of ChinaChengdu 610054

The group recommendation system is a viral requirement for the Internet service provider to provide recommendation services for all the users in a group. Due to the shared or different interests among users in the group, it is difficult for traditional personal recommendation algorithms to predict items that can meet the requirements of all the users in the group. In this paper, a random group recommendation model is proposed to recommend the top K most appealing items for all the users in a random group. By analyzing item ratings of all the users in the group, the recommendation model can abstract the group as a virtual user. Then a personal recommendation algorithm is applied to suggest the top K most appealing items for the virtual user. And the preference score and fuzzy clustering algorithm based on multiclass are applied to optimize the recommendation result of the group recommendation model. Finally, the Movie Lens-100 K dataset is applied to verify the efficiency of the recommendation model. The experimental results show that the items recommended by the proposed group recommendation model are more popular for all the users in the group than the items recommended by traditional group recommendation algorithms.

关键词： services app service

Molecularly Imprinted Polymers with Bi-functional Monomers of Polymerizable Cyclodextrin Derivatives and 2-(Diethylamino)-ethyl Methacrylate for Recognition of Norfloxacin in Aqueous Media

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Chinese Chemical Letters 2006年第5期17卷 641-644页

作者： zhi Feng xu Lan LIU qin Ying DENG School of Chemistry and Chemical Engineering Sun Yat-sen University Guangzhou 510275 Department of Chemistry and Material Science Hengyang Normal University Hengyang 421008

A molecularly imprinted polymer was synthesized using 2-（diethylamino）ethylmethacry -late（DEM） and bismethacryloyl-β-cyclodextrin（BMA-β-CD） as bi-functional monomers and norfloxacin（NOF） as a template. The results of equilibrium binding experiments indicated that the polymer has affinity and specificity for NOF in aqueous media, and that its selective recognition ability for the template was higher than that of the imprinted polymers synthesized with a single functional monomer （BMA-β-CD or DEM）.

关键词： Molecular imprinting norfloxacin β-cyclodextrin binding specificity.