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Nuclear Science and Techniques 2024年第5期35卷 173-185页

作者： he-lin gong Han Li Dunhui Xiao Sibo Cheng Paris Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences Tongji UniversityShanghai 200092China Department of Computing Data Science InstituteImperial College LondonLondon SW72AZUK

The aging of operational reactors leads to increased mechanical vibrations in the reactor *** vibration of the incore sensors near their nominal locations is a new problem for neutronic field *** field-reconstruction methods fail to handle spatially moving *** this study,we propose a Voronoi tessellation technique in combination with convolutional neural networks to handle this *** from movable in-core sensors were projected onto the same global field structure using Voronoi tessellation,holding the magnitude and location information of the *** convolutional neural networks were used to learn maps from observations to the global *** proposed method reconstructed multi-physics fields(including fast flux,thermal flux,and power rate)using observations from a single field(such as thermal flux).Numerical tests based on the IAEA benchmark demonstrated the potential of the proposed method in practical engineering applications,particularly within an amplitude of 5 cm around the nominal locations,which led to average relative errors below 5% and 10% in the L_(2) and L_(∞)norms,respectively.

关键词： Voronoi tessellation Field reconstruction Nuclear reactors Reactor physics On-line monitoring

Physics-constrained neural network for solving discontinuous interface K-eigenvalue problem with application to reactor physics

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Nuclear Science and Techniques 2023年第10期34卷 178-200页

作者： Qi-Hong Yang Yu Yang Yang-Tao Deng Qiao-lin he he-lin gong Shi-Quan Zhang School of Mathdematics Sichuan UniversityChengdu 610065China Paris Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China

Machine learning-based modeling of reactor physics problems has attracted increasing interest in recent *** some progress in one-dimensional problems,there is still a paucity of benchmark studies that are easy to solve using traditional numerical methods albeit still challenging using neural networks for a wide range of practical *** present two networks,namely the Generalized Inverse Power Method Neural Network(GIPMNN)and Physics-Constrained GIPMNN(PC-GIPIMNN)to solve K-eigenvalue problems in neutron diffusion *** follows the main idea of the inverse power method and determines the lowest eigenvalue using an iterative *** PC-GIPMNN additionally enforces conservative interface conditions for the neutron ***,Deep Ritz Method(DRM)directly solves the smallest eigenvalue by minimizing the eigenvalue in Rayleigh quotient form.A comprehensive study was conducted using GIPMNN,PC-GIPMNN,and DRM to solve problems of complex spatial geometry with variant material domains from the fleld of nuclear reactor *** methods were compared with the standard flnite element *** applicability and accuracy of the methods are reported and indicate that PC-GIPMNN outperforms GIPMNN and DRM.

关键词： Neural network Reactor physics Neutron diffusion equation Eigenvalue problem Inverse power method

Ensemble Bayesian method for parameter distribution inference:application to reactor physics

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Nuclear Science and Techniques 2023年第12期34卷 216-228页

作者： Jia‑Qin Zeng Hai‑Xiang Zhang he‑lin gong Ying‑Ting Luo School of Mathematics Sichuan UniversityChengdu 610065China Paris Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China

The estimation of model parameters is an important subject in *** this area of work,the prevailing approach is to estimate or calculate these as deterministic *** this study,we consider the model parameters from the perspective of random variables and describe the general form of the parameter distribution inference *** this framework,we propose an ensemble Bayesian method by introducing Bayesian inference and the Markov chain Monte Carlo(MCMC)*** on a finite cylindrical reactor and a 2D IAEA benchmark problem show that the proposed method converges quickly and can estimate parameters effectively,even for several correlated parameters *** experiments include cases of engineering software calls,demonstrating that the method can be applied to engineering,such as nuclear reactor engineering.

关键词： Model parameters Bayesian inference Frequency distribution Ensemble Bayesian method KL divergence

Optimizing near-carbon-free nuclear energy systems:advances in reactor operation digital twin through hybrid machine learning algorithms for parameter identification and state estimation

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Nuclear Science and Techniques 2024年第8期35卷 177-203页

作者： Li‑Zhan Hong he‑lin gong Hong‑Jun Ji Jia‑Liang Lu Han Li Qing Li Paris Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610041China

Accurate and efficient online parameter identification and state estimation are crucial for leveraging digital twin simulations to optimize the operation of near-carbon-free nuclear energy *** previous studies,we developed a reactor operation digital twin(RODT).However,non-differentiabilities and discontinuities arise when employing machine learning-based surrogate forward models,challenging traditional gradient-based inverse methods and their *** study investigated deterministic and metaheuristic algorithms and developed hybrid algorithms to address these *** efficient modular RODT software framework that incorporates these methods into its post-evaluation module is presented for comprehensive *** methods were rigorously assessed based on convergence profiles,stability with respect to noise,and computational *** numerical results show that the hybrid KNNLHS algorithm excels in real-time online applications,balancing accuracy and efficiency with a prediction error rate of only 1%and processing times of less than 0.1 ***,algorithms such as FSA,DE,and ADE,although slightly slower(approximately 1 s),demonstrated higher accuracy with a 0.3%relative L_2 error,which advances RODT methodologies to harness machine learning and system modeling for improved reactor monitoring,systematic diagnosis of off-normal events,and lifetime management *** developed modular software and novel optimization methods presented offer pathways to realize the full potential of RODT for transforming energy engineering practices.

关键词： Parameter identification State estimation Reactor operation digital twin Reduced order model Inverse problem

Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2

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Neural Regeneration Research 2025年第6期20卷 1801-1815页

作者： Qing he Zhen Wang Yuchen Wang Mengjie Zhu Zhile Liang Kanghong Zhang Yuge Xu gong Chen GHM Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina

Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain.

关键词： aquaporin-4 Ascl1 astrocyte cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 reprogramming

Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis

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Neural Regeneration Research 2025年第4期20卷 1103-1123页

作者： Xiahong Tang Nan Zheng Qingming lin Yan You Zheng gong Yangping Zhuang Jiali Wu Yu Wang Hanlin Huang Jun Ke Feng Chen Shengli Clinical Medical College of Fujian Medical University Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Emergency Fujian Provincial HospitalFuzhouFujian ProvinceChina Fujian Provincial Key Laboratory of Emergency Medicine FuzhouFujian ProvinceChina The Second Department of Intensive Care Unit Fujian Provincial Hospital South BranchFuzhouFujian ProvinceChina

Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological *** preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are *** this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB ***,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by *** results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these *** conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.

关键词： bone marrow–derived mesenchymal stem cells cardiac arrest cardiac resuscitation hypoxic preconditioning liver isoform of phosphofructokinase mitochondria neuroinflammation oxidative stress pyroptosis reactive oxygen species

Nonlinear stability of rarefaction waves for a viscous radiative and reactive gas with large initial perturbation

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Science China Mathematics 2021年第12期64卷 2637-2666页

作者： Guiqiong gong lin he Yongkai Liao School of Mathematics and Statistics Wuhan UniversityWuhan 430072China Hubei Key Laboratory of Computational Science Wuhan UniversityWuhan 430072China College of Mathematics Sichuan UniversityChengdu 610064China Institute of Applied Physics and Computational Mathematics Beijing 100088China

We investigate the time-asymptotically nonlinear stability of rarefaction waves to the Cauchy problem of a one-dimensional compressible Navier-Stokes type system for a viscous,compressible,radiative and reactive gas,where the constitutive relations for the pressure p,the speci c internal energy e,the speci c volume v,the absolute temperature θ,and the specific entropy s are given by p=Rθv+aθ^(4)/3,e=C_(v)θ+avθ^(4),and s=C_(v)lnθ+4avθ^(3)/3+Rln v with R>0,C_(v)>0 and a>0 being the perfect gas constant,the speci c heat and the radiation constant,*** such a specific gas motion,a somewhat surprising fact is that,generally speaking,the pressure p(v,s)is not a convex function of the specific volume v and the specific entropy *** so,we show in this paper that the rarefaction waves are time-asymptotically stable for large initial perturbation provided that the radiation constant a and the strength of the rarefaction waves are sufficiently *** key point in our analysis is to deduce the positive lower and upper bounds on the specific volume and the absolute temperature,which are uniform with respect to the space and the time variables,but are independent of the radiation constant a.

关键词： viscous radiative and reactive gas rarefaction waves nonlinear stability large initial perturbation

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毛囊类器官研究:现状、问题与前景

中国组织工程研究 2025年第31期29卷 6733-6742页

作者：王钊龚琳朴永君大连医科大学附属第一医院皮肤科辽宁省大连市116000

背景:毛囊体外重建依赖于毛乳头细胞及角质形成细胞3D共培养时的自组装行为,该过程与毛囊胚胎发育极为相似,因此,毛囊类器官可作为毛囊再生相关基础研究良好的体外模型,目前,通过仿生系统培养的全人源毛囊类器官已能成功移植到动物体内... 详细信息

背景:毛囊体外重建依赖于毛乳头细胞及角质形成细胞3D共培养时的自组装行为,该过程与毛囊胚胎发育极为相似,因此,毛囊类器官可作为毛囊再生相关基础研究良好的体外模型,目前,通过仿生系统培养的全人源毛囊类器官已能成功移植到动物体内。毛囊类器官研究使毛囊再生成为可能,但构建方法亦无统一定论,仍面临诸多挑战。目的:综述目前毛囊类器官的研究进展,总结毛囊类器官培养方法及表征,阐述应用前景,为后续研究提供可靠依据,以期促进其在组织工程及脱发治疗的临床转化。方法:应用计算机在中国知网(CNKI)及PubMed数据库中,以“毛囊再生,毛发再生,类器官”为中文检索词,“hair growth,hair loss,hair regeneration,hair follicle,dermal papilla cell,organoid”为英文检索词进行检索,查阅国内外关于毛囊类器官的相关文献,共纳入文献67篇进行后续分析。结果与结论:①不同来源的毛乳头细胞与角质形成细胞可在体外构建毛囊类器官,以获得鼠源、人-鼠嵌合及人源毛囊类器官,并成功用于啮齿动物移植模型;②多种重编程方法如电刺激、添加重组蛋白、解离细胞基因过表达等可用于促进毛囊类器官毛胚形成及毛钉伸长,同时,多种3D打印技术的应用已实现大小可控毛囊类器官的批量生产,极大提高了生产效率;③在解离细胞共培养体系中加入黑素细胞时,或可破译新生毛囊的色素缺失难题,而加入人脐静脉血管内皮细胞时,细胞聚集体内的新生血管可改善营养供给,减少中心部位坏死;④随着工程化类毛囊技术逐渐趋于成熟,患者自体细胞构建的毛囊类器官或可用于严重脱发的个体化医疗。

关键词：脱发毛囊再生毛乳头细胞毛囊类器官上皮-间充质交互作用 3D培养类器官组织工程工程化类器官

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Potassium and calcium channels in different nerve cells act as therapeutic targets in neurological disorders

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Neural Regeneration Research 2025年第5期20卷 1258-1276页

作者： Qing Qiu Mengting Yang Danfeng gong Haiying Liang Tingting Chen Department of Pharmacology School of PharmacyNantong UniversityNantongJiangsu ProvinceChina Jiangsu Province Key Laboratory of Inflammation and Molecular Drug Target NantongJiangsu ProvinceChina Department of Pharmacy Longyan First Affiliated Hospital of Fujian Medical UniversityLongyanFujian ProvinceChina

The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central nervous system, with sensory stimulation and excitation conduction functions. Astrocytes and microglia belong to the glial cell family, which is the main source of cytokines and represents the main defense system of the central nervous system. Nerve cells undergo neurotransmission or gliotransmission, which regulates neuronal activity via the ion channels, receptors, or transporters expressed on nerve cell membranes. Ion channels, composed of large transmembrane proteins, play crucial roles in maintaining nerve cell homeostasis. These channels are also important for control of the membrane potential and in the secretion of neurotransmitters. A variety of cellular functions and life activities, including functional regulation of the central nervous system, the generation and conduction of nerve excitation, the occurrence of receptor potential, heart pulsation, smooth muscle peristalsis, skeletal muscle contraction, and hormone secretion, are closely related to ion channels associated with passive transmembrane transport. Two types of ion channels in the central nervous system, potassium channels and calcium channels, are closely related to various neurological disorders, including Alzheimer's disease, Parkinson's disease, and epilepsy. Accordingly, various drugs that can affect these ion channels have been explored deeply to provide new directions for the treatment of these neurological disorders. In this review, we focus on the functions of potassium and calcium ion channels in different nerve cells and their involvement in neurological disorders such as Parkinson's disease, Alzheimer's disease, depression, epilepsy, autism, and rare disorders. We also describe several clinical drugs that target potassium or calcium channels in nerve cells and could be u

关键词： astrocytes calcium channels central nervous system extracellular ion concentration microglia neurological disorders neurons potassium channels

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土槽模拟开沟覆膜滴灌技术下盐分调控规律

节水灌溉 2016年第10期 28-33页

作者：叶建威刘洪光何新林龚萍张杰阿尔娜古丽.艾买提石河子大学水利建筑工程学院现代节水灌溉兵团重点实验室新疆石河子832000

新疆气候干旱与土壤盐碱化并存,是制约新疆农业发展的主要因素,开沟覆膜滴灌技术综合了膜下滴灌技术与开沟技术的优点,理论上可有效治理盐碱地。在开沟覆膜滴灌技术下,设置不同灌水定额与灌水次数,利用试验土槽模拟盐分调控规律,结果表... 详细信息

新疆气候干旱与土壤盐碱化并存,是制约新疆农业发展的主要因素,开沟覆膜滴灌技术综合了膜下滴灌技术与开沟技术的优点,理论上可有效治理盐碱地。在开沟覆膜滴灌技术下,设置不同灌水定额与灌水次数,利用试验土槽模拟盐分调控规律,结果表明：1第1次合适灌水定额对盐分的淋洗起主要作用,可使土体盐分达到较稳定的状态,盐分也随水分侧向运移,并在土埂表层聚集;2灌水定额的增加促进盐分随水分向远离滴头和向深层方向运移,使得覆膜间、覆膜边盐分淋洗的深度增加,脱盐区增加;3在灌水定额为300m3/hm2时,可以在滴灌带横向023cm,下部58cm处迅速形成一个含盐量小于1.5%的达标脱盐区,满足当地作物正常出苗,故建议当地可选择300m3/hm2作为第1次灌水洗盐定额。

关键词：滴灌开沟覆膜盐碱地灌水定额