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Nuclear Science and Techniques 2024年第1期35卷 45-58页

作者： Yi-Xing Lu wen-cheng fang Yu-Sen Guo Zhen-Tang Zhao Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800China University of Chinese Academy of Sciences Beijing 101408China Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201204China Shanghai Key Laboratory of Cryogenics&Superconducting RF Technology Shanghai 201800China ShanghaiTech University Shanghai 201210China

Radio frequency quadrupoles(RFQs),which are crucial components of proton injectors,significantly affect the performance of proton accelerator facilities.An RFQ with a high frequency of 714 MHz dedicated to compact proton injectors for medi-cal applications is designed in this study.The RFQ is designed to accelerate proton beams from 50 keV to 4 MeV within a short length of 2 m and can be matched closely with the downstream drift tube linac to capture more particles through a preliminary optimization.To develop an advanced RFQ,challenging techniques,including fabrication and tuning method,must be evaluated and verified using a prototype.An aluminium prototype is derived from the conceptual design of the RFQ and then redesigned to confirm the radio frequency performance,fabrication procedure,and feasibility of the tuning algorithm.Eventually,a new tuning algorithm based on the response matrix and least-squares method is developed,which yields favorable results based on the prototype,i.e.,the errors of the dipole and quadrupole components reduced to a low level after several tuning iterations.Benefiting from the conceptual design and techniques obtained from the prototype,the formal mechanical design of the 2-m RFQ is ready for the next manufacturing step.

关键词： Compact proton injector RFQ IH-DTL High gradient Tuning

Corporate Credit Ratings Based on Hierarchical Heterogeneous Graph Neural Networks

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Machine Intelligence Research 2024年第2期21卷 257-271页

作者： Bo-Jing Feng Xi cheng Hao-Nan Xu wen-fang Xue Center for Research on Intelligent Perception and Computing National Laboratory of Pattern RecognitionInstitute of AutomationChinese Academy of SciencesBeijing 100190China

order to help investors understand the credit status of target corporations and reduce investment risks,the corporate credit rating model has become an important evaluation tool in the financial market.These models are based on statistical learning,machine learning and deep learning especially graph neural networks(GNNs).However,we found that only few models take the hierarchy,heterogeneity or unlabeled data into account in the actual corporate credit rating process.Therefore,we propose a novel framework named hierarchical heterogeneous graph neural networks(HHGNN),which can fully model the hierarchy of corporate features and the heterogeneity of relationships between corporations.In addition,we design an adversarial learning block to make full use of the rich unlabeled samples in the financial data.Extensive experiments conducted on the public-listed corporate rating dataset prove that HHGNN achieves SOTA compared to the baseline methods.

关键词： Corporate credit rating hierarchical relation heterogeneous graph neural networks adversarial learning

Early adenocarcinoma mixed with a neuroendocrine carcinoma component arising in the gastroesophageal junction: A case report

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 563-570页

作者： Yu-Qing cheng Geng-fang Wang Xiao-Li Zhou Min Lin Xin-wen Zhang Qin Huang Department of Pathology The Affiliated Changzhou No.2 People’s Hospital of Nanjing Medical UniversityChangzhou 213164Jiangsu ProvinceChina Gastroenterology Center The Affiliated Changzhou No.2 People’s Hospital of Nanjing Medical UniversityChangzhou 213164Jiangsu ProvinceChina Graduate School Dalian Medical UniversityDalian 116044Liaoning ProvinceChina Department of Pathology Beth Israel Deaconess Medical Center and Harvard Medical SchoolBostonMA 02215United States

BACKGROUND Early adenocarcinoma mixed with a neuroendocrine carcinoma(NEC)component arising in the gastroesophageal junctional(GEJ)region is rare and even rarer in young patients.Here,we report such a case in a 29-year-old Chinese man.CASE SUMMARY This patient presented to our hospital with a 3-mo history of dysphagia and regurgitation.Upper endoscopy revealed an elevated nodule in the distal esophagus 1.6 cm above the GEJ line,without Barrett’s esophagus or involvement of the gastric cardia.The nodule was completely resected by endoscopic submu-cosal dissection(ESD).Pathological examination confirmed diagnosis of intra-mucosal adenocarcinoma mixed with an NEC component,measuring 1.5 cm.Immunohistochemically,both adenocarcinoma and NEC components were positive for P53 with a Ki67 index of 90%;NEC was positive for synaptophysin and chromogranin.Next-generation sequencing of 196 genes demonstrated a novel germline mutation of the ERCC3 gene in the DNA repair pathway and a germline mutation of the RNF43 gene,a common gastric cancer driver gene,in addition to pathogenic somatic mutations in P53 and CHEK2 genes.The patient was alive without evidence of the disease 36 mo after ESD.CONCLUSION Early adenocarcinoma with an NEC component arising in the distal esophageal side of the GEJ region showed evidence of gastric origin.

关键词： Adenocarcinoma Neuroendocrine carcinoma Gastroesophageal junction Next generation sequencing Case report

Elucidating the cardioprotective mechanisms of sodium-glucose cotransporter-2 inhibitors beyond glycemic control

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World Journal of Diabetes 2024年第2期15卷 137-141页

作者： Ke-Xin Zhang cheng-Xia Kan fang Han Jing-wen Zhang Xiao-Dong Sun Department of Endocrinology and Metabolism Affiliated Hospital of Weifang Medical UniversityWeifang 261031Shandong ProvinceChina

Sodium-glucose cotransporter-2(SGLT2)inhibitors have emerged as a pivotal intervention in diabetes management,offering significant cardiovascular benefits.Empagliflozin,in particular,has demonstrated cardioprotective effects beyond its glucose-lowering action,reducing heart failure hospitalizations and improving cardiac function.Of note,the cardioprotective mechanisms appear to be independent of glucose lowering,possibly mediated through several mechanisms involving shifts in cardiac metabolism and anti-fibrotic,anti-inflammatory,and anti-oxidative pathways.This editorial summarizes the multifaceted cardiovascular advantages of SGLT2 inhibitors,highlighting the need for further research to elucidate their full therapeutic potential in cardiac care.

关键词： Diabetes Sodium-glucose cotransporter-2 Cardiovascular diseases Empagliflozin

Monte Carlo Simulation-Based Robust Workflow Scheduling for Spot Instances in Cloud Environments

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Tsinghua Science and Technology 2024年第1期29卷 112-126页

作者： Quanwang Wu Jianzhao fang Jie Zeng Junhao wen Fengji Luo College of Computer Science Chongqing UniversityChongqing 400044China National Experimental Teaching Demonstration Center Chongqing UniversityChongqing 400044China College of Big Data and Software Engineering Chongqing UniversityChongqing 400044China School of Civil Engineering The University of SydneySydney 2006Australia

When deploying workflows in cloud environments,the use of Spot Instances(SIs)is intriguing as they are much cheaper than on-demand ones.However,Sls are volatile and may be revoked at any time,which results in a more challenging scheduling problem involving execution interruption and hence hinders the successful handling of conventional cloud workflow scheduling techniques.Although some scheduling methods for Sls have been proposed,most of them are no more applicable to the latest Sls,as they have evolved by eliminating bidding and simplifying the pricing model.This study focuses on how to minimize the execution cost with a deadline constraint when deploying a workflow on volatile Sls in cloud environments.Based on Monte Carlo simulation and list scheduling,a stochastic scheduling method called MCLS is devised to optimize a utility function introduced for this problem.With the Monte Carlo simulation framework,MCLS employs sampled task execution time to build solutions via deadline distribution and list scheduling,and then returns the most robust solution from all the candidates with a specific evaluation mechanism and selection criteria.Experimental results show that the performance of MCLS is more competitive comparedwithtraditionalalgorithms.

关键词： constrained optimization Monte Carlo simulation robustness Spot Instances(Sls) workflow scheduling

Factors affecting meibomian gland area loss in symptomatic adults

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1036-1041页

作者： Si-cheng Ding Jing-Jing Su Qing Zhan Jiao-Man Wang fang Zheng Xu-Xuan fang Dan cheng Ping Guo The Second Clinical Medical College Jinan UniversityShenzhen 518000Guangdong ProvinceChina Shenzhen Eye Hospital Jinan UniversityShenzhen Eye InstituteShenzhen 518040Guangdong ProvinceChina Department of Ophthalmology Jinzhou Medical UniversityJinzhou 121000Liaoning ProvinceChina

AIM:To characterize the distribution of meibomian gland(MG)area loss(MGL)and its relationship with demographic characteristics,mites,and symptoms.METHODS:This retrospective observational study included patients who visited the Dry Eye Clinic of Shenzhen Eye Hospital between June 2020 and August 2021.General patient characteristics,ocular symptoms,Demodex test results of the eyelid edges,and the results of a comprehensive ocular surface analysis were collected.MGL was analyzed using Image J software.RESULTS:This study enrolled 1204 outpatients aged 20-80(40.70±13.44)y,including 357 males(29.65%)and 847 females(70.35%).The patients were classified into mild(n=155;12.87%),moderate(n=795;66.03%),severe(n=206;17.11%),and extremely severe(n=48;3.99%)MGL groups.MGL was significantly larger in female than in male(P=0.006).The degree of MGL also significantly differed in age(P<0.001)and the more numbers of mites with severity(P<0.001).Multivariate disordered multinomial logistic regression analysis identified that female sex,older age,secretory symptoms,and a large number of mites were risk factors for MGL(P<0.05).CONCLUSION:Patients with MGL are more likely to be older,female,more numbers of mites,and increased secretion.

关键词： meibomianglands aging sex symptomatology Demodex

Cascaded four-wave mixing all-optical wavelength converter based on highly nonlinear fiber deposited graphene oxide

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Journal of Materials Science & Technology 2024年第4期171卷 10-15页

作者： Yuanhongliu Gao Xiaoyu Chen Tonglei cheng fang Wang Xin Yan College of Information Science and Engineering State Key Laboratory of Synthetical Automation for Process IndustriesNortheastern UniversityShenyang 110819China

The all-optical wavelength conversion using cascaded four-wave mixing(FWM)phenomena with graphene oxide(GO)and a highly nonlinear fiber(HNLF)device is demonstrated experimentally.GO has a strong third-order nonlinear effect and is an excellent nonlinear optical material for nonlinear optical wavelength conversion.The group velocity matching of pump and signal,HNLF,and GO amplification promote the cascaded nonlinear frequency mixing process.From the experimental and analytical results,the maximum spacing between signal and pump is 21 nm,and specifically,the order of cascaded FWM light increases from order 1 to order 2 with increasing GO,and the first-order FWM conversion effi-ciency increases to a maximum of−14.5 dB.To the best of our knowledge,this is the first time that cascaded FWM-based all-optical wavelength conversion in HNLF-GO with wide wavelength selectivity is investigated with combined pump and signal light.Our findings not only provide an effective method for achieving all-optical wavelength conversion in cascaded FWM but also offer the possibility of fabricating high-performance nonlinear optical devices.

关键词： Four-wave mixing Graphene oxide Highly nonlinear fiber Optical wavelength conversion

Photonic neuromorphic architecture for tens-of-task lifelong learning

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Light(Science & Applications) 2024年第3期13卷 519-530页

作者： Yuan cheng Jianing Zhang Tiankuang Zhou Yuyan Wang Zhihao Xu Xiaoyun Yuan Lu fang Sigma Laboratory Department of Electronic EngineeringTsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology(BNRist) Beijing 100084China Institute for Brain and Cognitive Science Tsinghua University(THUIBCS)Beijing 100084China

Scalable,high-capacity,and low-power computing architecture is the primary assurance for increasingly manifold and large-scale machine learning tasks.Traditional electronic artificial agents by conventional power-hungry processors have faced the issues of energy and scaling walls,hindering them from the sustainable performance improvement and iterative multi-task learning.Referring to another modality of light,photonic computing has been progressively applied in high-efficient neuromorphic systems.Here,we innovate a reconfigurable lifelong-learning optical neural network(L2 ONN),for highly-integrated tens-of-task machine intelligence with elaborated algorithm-hardware codesign.Benefiting from the inherent sparsity and parallelism in massive photonic connections,L2 ONN learns each single task by adaptively activating sparse photonic neuron connections in the coherent light field,while incrementally acquiring expertise on various tasks by gradually enlarging the activation.The multi-task optical features are parallelly processed by multi-spectrum representations allocated with different wavelengths.Extensive evaluations on freespace and on-chip architectures confirm that for the first time,L2 ONN avoided the catastrophic forgetting issue of photonic computing,owning versatile skills on challenging tens-of-tasks(vision classification,voice recognition,medical diagnosis,etc.)with a single model.Particularly,L2 ONN achieves more than an order of magnitude higher efficiency than the representative electronic artificial neural networks,and 14×larger capacity than existing optical neural networks while maintaining competitive performance on each individual task.The proposed photonic neuromorphic architecture points out a new form of lifelong learning scheme,permitting terminal/edge AI systems with light-speed efficiency and unprecedented scalability.

关键词： life neural versatile

Orbital angular momentum-mediated machine learning for high-accuracy mode-feature encoding

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Light(Science & Applications) 2024年第3期13卷 466-477页

作者： Xinyuan fang Xiaonan Hu Baoli Li Hang Su Ke cheng Haitao Luan Min Gu Institute of Photonic Chips University of Shanghai for Science and TechnologyShanghai 200093China Centre for Artificial-Intelligence Nanophotonics School of Optical-Electrical and Computer EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China

Machine learning with optical neural networks has featured unique advantages of the information processing including high speed,ultrawide bandwidths and low energy consumption because the optical dimensions(time,space,wavelength,and polarization)could be utilized to increase the degree of freedom.However,due to the lack of the capability to extract the information features in the orbital angular momentum(OAM)domain,the theoretically unlimited OAM states have never been exploited to represent the signal of the input/output nodes in the neural network model.Here,we demonstrate OAM-mediated machine learning with an all-optical convolutional neural network(CNN)based on Laguerre-Gaussian(LG)beam modes with diverse diffraction losses.The proposed CNN architecture is composed of a trainable OAM mode-dispersion impulse as a convolutional kernel for feature extraction,and deep-learning diffractive layers as a classifier.The resultant OAM mode-dispersion selectivity can be applied in information mode-feature encoding,leading to an accuracy as high as 97.2%for MNIST database through detecting the energy weighting coefficients of the encoded OAM modes,as well as a resistance to eavesdropping in point-to-point free-space transmission.Moreover,through extending the target encoded modes into multiplexed OAM states,we realize all-optical dimension reduction for anomaly detection with an accuracy of 85%.Our work provides a deep insight to the mechanism of machine learning with spatial modes basis,which can be further utilized to improve the performances of various machine-vision tasks by constructing the unsupervised learning-based auto-encoder.

关键词： polarization mode momentum

Preparation and properties of Ti_(3)SiC(2) -based corrosion mitigation coatings for SiC_(f) /SiC PWR accident tolerant fuel cladding

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Journal of Advanced Ceramics 2024年第1期13卷 73-85页

作者： Jinsong Yang fang Ye Laifei cheng Kai Zhao Yucong Wei Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China

To enhance the resistance of SiC_(f)/SiC to hydrothermal corrosion in the pressurized water reactor(PWR)environment,structurally tunable Ti_(3)SiC(2)-based corrosion mitigation coatings for SiC_(f)/SiC were prepared using molten salt synthesis.The influence of various process parameters,such as Si/Ti molar ratio in raw materials,annealing time,and annealing temperature,on the phase composition and the structure of the coatings was explored.Through the process control,the fabricated coatings can be either Ti_(3)SiC(2) monolithic structure or TiC/Ti_(3)SiC(2) and TiC/Ti_(3)SiC(2)/Ti_(5)Si_(3)C_(x) multilayered structures.The coatings demonstrate strong bonding to the substrate due to in-situ reaction,exhibiting tensile and shear strength of at least 26.9 and 30.8 MPa,respectively.Incorporating TiC as a transition layer further enhances the tensile and shear strength to 41.3 and 51.4 MPa,respectively.Monolithic Ti_(3)SiC(2) coatings enhance the thermal conductivity of SiC_(f)/SiC by 10%–12%.Notably,Ti_(3)SiC(2) coatings effectively protect SiC_(f)/SiC from hydrothermal corrosion,demonstrating an 83%strength retention rate compared to 71%in the control group after corrosion.However,the Ti5Si3Cx layer exhibits unsatisfactory corrosion mitigation.The Ti_(3)SiC(2) monolithic coating has higher thermal conductivity,TiC/Ti_(3)SiC(2) multi-layered coating has higher bonding strength,and both have desirable resistance to the hydrothermal corrosion.

关键词： Ti_(3)SiC(2) SiC_(f)/SiC nuclear materials hydrothermal corrosion coating