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Research 2024年第2期2023卷 149-157页

作者： Haojie han Qinghua Zhang Wei Li Yiqun Liu Jiasheng guo Yue Wang Qian Li lin Gu Ce-Wen Nan Jing Ma State Key Laboratory of New Ceramics and Fine Processing Schoolof Materials Science and EngineeringTsinghua UniversityBeijing 100084China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

The oxygen octahedral rotation(OOR)forms fundamental atomic distortions and symmetries in perovskite oxides and definitely determines their properties and ***,epitaxial strain and interfacial structural coupling engineering have been developed to modulate the OOR patterns and explore novel properties,but it is difficult to distinguish the 2 ***,different symmetries are induced in Na_(0.5)Bi_(0.5)TiO_(3)(NBT)epitaxial films by interfacial oxygen octahedral coupling rather than epitaxial *** NBT film grown on the Nb:SrTiO_(3)substrate exhibits a paraelectric tetragonal phase,while with La_(0.5)Sr_(0.5)MnO_(3)as a buffer layer,a monoclinic phase and robust ferroelectricity are obtained,with a remanent polarization of 42μC cm^(-2)and a breakdown strength of 7.89 MV cm^(-1),which are the highest record among NBT-based ***,the interfacial oxygen octahedral coupling effect is demonstrated to propagate to the entire thickness of the film,suggesting an intriguing long-range *** work provides a deep insight into understanding the structure modulation in perovskite heterostructures and an important avenue for achieving unique functionalities.

关键词： effect. interfacial coupling

NeuroPrim:An attention-based model for solving NP-hard spanning tree problems

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Science China Mathematics 2024年第6期67卷 1359-1376页

作者： Yuchen Shi Congying han Tiande guo School of Mathematical Sciences University of Chinese Academy of SciencesBeijing100049China

Spanning tree problems with specialized constraints can be difficult to solve in real-world scenarios,often requiring intricate algorithmic design and exponential ***,there has been growing interest in end-to-end deep neural networks for solving routing ***,such methods typically produce sequences of vertices,which make it difficult to apply them to general combinatorial optimization problems where the solution set consists of edges,as in various spanning tree *** this paper,we propose NeuroPrim,a novel framework for solving various spanning tree problems by defining a Markov decision process for general combinatorial optimization problems on *** approach reduces the action and state space using Prim's algorithm and trains the resulting model using *** apply our framework to three difficult problems on the Euclidean space:the degree-constrained minimum spanning tree problem,the minimum routing cost spanning tree problem and the Steiner tree problem in *** results on literature instances demonstrate that our model outperforms strong heuristics and achieves small optimality gaps of up to 250 ***,we find that our model has strong generalization ability with no significant degradation observed on problem instances as large as 1,*** results suggest that our framework can be effective for solving a wide range of combinatorial optimization problems beyond spanning tree problems.

关键词： degree-constrained minimum spanning tree problem minimum routing cost spanning tree problem Steiner tree problem in graphs Prim's algorithm reinforcement learning

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Investigation on the influence of vortex generator on particle resuspension

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Particuology 2024年第3期86卷 126-136页

作者： Dongchi Yu Jun-Li lin Jin-han Xie ASML 80W Tasman DrSan Jose95134CaliforniaUSA Department of Mechanics and Engineering Science at College of Engineering and State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing100081China

The vortex generator(VG)and its well-known effect in flow optimization are widely studied and employed across different engineering ***,while the same working principles of VG may be well suited for the applications on surface-cleaning technologies,such promising potential is hardly,if any,explored in the published ***,in the present study,the influence on flow-induced particle resuspension brought by a rectangular vG in a channel flow is investigated with the help of highfidelity computational fluid dynamics *** increases of particle removal forces and resuspension rates are discovered in long,strip-like regions with reduced boundary-layer thickness resulted from the vG-induced vortices,and the enhancement effect is especially significant for configurations with the VG installed at a greater angle of *** is also shown that while the resuspension enhancements on the lower and the upper surfaces of the channel exhibit distinct statistical characteristics,having a VG in the channel improves the overall particle-removing capability of the channel flow by introducing higher surface-averaged removal forces and particle resuspension *** but not least,the increase of resuspension rate is especially significant for the smaller,micron-scale particles which are otherwise hardly disturbed by a VG-less channel flow,and such resuspension-enhancement effectgenerally subsides with increasing particle size.

关键词： Particle resuspension Vortexgenerator CFD Surface cleaning

ATP6AP2,a regulator of LRP6/β-catenin protein trafficking,promotes Wnt/β-catenin signaling and bone formation in a cell type dependent manner

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Bone Research 2024年第2期12卷 453-468页

作者： Lei Xiong Hao-han guo Jin-Xiu Pan Xiao Ren Daehoon Lee Li Chen lin Mei Wen-Cheng Xiong Department of Neurosciences School of MedicineCase Western Reserve UniversityClevelandOH 44106USA Louis Stoke VA Medical Center ClevelandOH 44106USA

Wnt/β-catenin signaling is critical for various cellular processes in multiple cell types,including osteoblast(OB)differentiation and *** how Wnt/β-catenin signaling is regulated in OBs remain ***6AP2,an accessory subunit of V-ATPase,plays important roles in multiple cell types/organs and multiple signaling ***,little is known whether and how ATP6AP2 in OBs regulates Wnt/β-catenin signaling and bone *** we provide evidence for ATP6AP2 in the OB-lineage cells to promote OB-mediated bone formation and bone homeostasis selectively in the trabecular bone *** knocking out(CKO)ATP6AP2 in the OB-lineage cells(Atp6ap2^(Ocn-Cre))reduced trabecular,but not cortical,bone formation and bone *** and cellular biochemical studies revealed that LRP6 and N-cadherin were reduced in ATP6AP2-KO BMSCs and OBs,but not *** in vitro and in vivo studies revealed impairedβ-catenin signaling in ATP6AP2-KO BMSCs and OBs,but not osteocytes,under both basal and Wnt stimulated conditions,although LRP5 was decreased in ATP6AP2-KO osteocytes,but not *** cell biological studies uncovered that osteoblastic ATP6AP2 is not required for Wnt3a suppression ofβ-catenin phosphorylation,but necessary for LRP6/β-catenin and N-cadherin/β-catenin protein complex distribution at the cell membrane,thus preventing their *** of activeβ-catenin diminished the OB differentiation deficit in ATP6AP2-KO *** together,these results support the view for ATP6AP2 as a critical regulator of both LRP6 and N-cadherin protein trafficking and stability,and thus regulatingβ-catenin levels,demonstrating an un-recognized function of osteoblastic ATP6AP2 in promoting Wnt/LRP6/β-catenin signaling and trabecular bone formation.

关键词： LRP6 impaired organs

Ultra-high NA graphene oxide flat lens on a fiber facet with near diffraction-limited focusing

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Photonics Research 2024年第7期12卷 1457-1463页

作者： XIAOKE CHEN lin MA ZUYUAN HE GUIYUAN CAO han lin BAOHUA JIA State Key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong UniversityShanghai 200240China Nanophotonics Research Center Shenzhen Key Laboratory of Micro-Scale Optical Information TechnologyShenzhen UniversityShenzhen 518060China School of Science RMIT UniversityMelbourne VIC 3000Australia The Australian Research Council(ARC)Industrial Transformation Training Centre in Surface Engineering for Advanced Materials(SEAM) RMIT UniversityMelbourne VIC 3000Australia

The realization of a high numerical aperture(NA) fiber lens is critical for achieving high imaging resolution in endoscopes, enabling subwavelength operation in optical tweezers and high efficiency coupling between optical fibers and photonic chips. However, it remains challenging with conventional design and fabrication. Here we propose an ultrathin(400 nm) graphene oxide(GO) film lens fabricated in situ on a standard single-mode fiber facet using the femtosecond laser direct writing technique. An extremely high NA of 0.89 is achieved with a near diffraction-limited focal spot(FWHM = 0.68λ), which is verified theoretically and experimentally. The diameter of the fabricated fiber GO lens is as small as 12 μm with no beam expansion structure. The proposed fiber GO lens is promising for applications such as super-resolution imaging, compact optical tweezers, medical endoscopes,and on-chip integration.

关键词： fiber high oxide

Flocking Effects of the Stochastic Cucker-Smale System with Noise

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Journal of Systems Science & Complexity 2024年第5期37卷 1978-1994页

作者： han Ning GE Bin LI lin School of Mathematical Sciences Harbin Engineering University

In this paper, the flocking behavior of a Cucker-Smale model with a leader and noise is studied in a finite time. The authors present a Cucker-Smale system with two nonlinear controls for a complex network with stochastic synchronization in probability. Based on the finite-time stability theory of stochastic differential equations, the sufficient conditions for the flocking of stochastic systems in a finite time are obtained by using the Lyapunov function method. Finally, the numerical simulation of the particle system is carried out for the leader and noise, and the correctness of the results is verified.

关键词： Cucker-Smale model flocking behavior leader noise

Distribution of oxide inclusions in H13 castings under super-gravity field with multi-stage rotation speeds

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Journal of Iron and Steel Research International 2024年第1期31卷 121-133页

作者： Shao-ying Li Xiao-jun Xi Xing-ming Zhao han-jie guo Jing guo School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing100083China Beijing Beiye Functional Materials Corporation Beijing100192China Shandong Tianwu Forming Technology Co. Ltd.Liaocheng252024ShandongChina

The 42 kg industrial H13 castings were prepared by different super-gravity fields with multi-rotation speeds,and the distribution of oxide inclusions in the castings was *** addition,the inward movement Reynolds number and inward movement time of oxide inclusions as well as the solidification time of molten steel at different positions in the castings were calculated to clarify the removal mechanism of oxide inclusions in super-gravity *** results show that the large size(i.e.,greater than 10μm)oxide inclusions are mainly concentrated in the inner and outer parts of the super-gravity castings with constant rotation speed(500 r min^(-1))and five-stage rotation speeds(500,600,750,850,and 950 r min^(-1)),respectively,while there are no large oxide inclusions in the super-gravity castings with three-stage rotation speeds(500,600,and 750 r min^(-1)).Although an increase in the particle size of inclusion and the rotation speed in super-gravity field is conducive to the increase in the inward movement Reynolds number of oxide inclusions and reduction in the inward movement time of oxide inclusions,it will reduce the local solidification time of molten *** the range of the rotation speed studied,the super-gravity field with three-stage rotation speeds has the best effect on the removal of inclusions in H13 molten steel.

关键词： Distribution Oxide inclusion H13 casting Super-gravity field Rotation speed

The competition between Bidens pilosa and Setaria viridis alters soil microbial composition and soil ecological function

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Journal of Integrative Agriculture 2024年第1期23卷 267-282页

作者： Qiao Li Jianying guo han Zhang Mengxin Zhao State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193China College of Life Science Yangtze UniversityJingzhou 434025China

Bidens pilosa is recognized as one of the major invasive plants in *** invasion has been associated with significant losses in agriculture,forestry,husbandry,and *** ecosystems play an important role in alien plant *** within the soil act as intermediaries between plants and soil ecological functions,playing a role in regulating soil enzyme activities and nutrient *** the interactions between invasive plants,soil microorganisms,and soil ecological processes is vital for managing and mitigating the impacts of invasive species on the *** this study,we conducted a systematic analysis focusing on *** and Setaria viridis,a common native companion plant in the invaded *** simulate the invasion process of ***,we constructed homogeneous plots consisting of *** and *** grown separately as monocultures,as well as in *** rhizosphere and bulk soils were collected from the alien plant *** and the native plant *** order to focus on the soil ecological functional mechanisms that contribute to the successful invasion of ***,we analyzed the effects of *** on the composition of soil microbial communities and soil ecological *** results showed that the biomass of *** increased by 27.51% and that of *** was significantly reduced by 66.56%.The organic matter contents in the bulk and rhizosphere soils of *** were approximately 1.30 times those in the native plant *** TN and NO_(3)^(-)contents in the rhizosphere soil of *** were 1.30 to 2.71 times those in the native plant *** activities of acid phosphatase,alkaline phosphatase,and urease in the rhizosphere soil of *** were 1.98-2.25 times higher than in the native plant *** high-throughput sequencing of the16S rRNA gene,we found that *** altered the composition of the soil microbial ***,many genera in Actinobacteria and Proteobacteri

关键词： plant invasion Bidens pilosa soil microbial composition soil properties soil enzyme activities

Lactate:a prospective target for therapeutic intervention in psychiatric disease

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Neural Regeneration Research 2024年第7期19卷 1473-1479页

作者： Yanhui Cai Haiyun guo Tianle han Huaning Wang Department of Psychiatry Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina Department of Anesthesiology and Perioperative Medicine Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina

Although antipsychotics that act via monoaminergic neurotransmitter modulation have considera ble therapeutic effect,they cannot completely relieve clinical symptoms in patients suffering from psychiatric disorde *** may be attributed to the limited range of neurotransmitters that are regulated by psychotropic *** findings indicate the need for investigation of psychotropic medications that target less-studied neurotransmitte *** these candidate neurotransmitters,lactate is developing from being a waste metabolite to a glial-neuronal signaling molecule in recent *** studies have suggested that cerebral lactate levels change considerably in numerous psychiatric illnesses;animal experiments have also shown that the supply of exogenous la ctate exerts an antidepressant *** this review,we have described how medications targeting newer neurotransmitte rs offer promise in psychiatric diseases;we have also summarized the advances in the use of lactate(and its corresponding signaling pathways)as a signaling *** addition,we have described the alterations in brain lactate levels in depression,anxiety,bipolar disorder,and schizophrenia and have indicated the challenges that need to be overcome before brain lactate can be used as a therapeutic target in psychopharmacology.

关键词： antidepressant anxiety bipolar disorder depression lactate psychiatric disease psychopharmacology schizophrenia signal molecular therapeutics

Machine learning model based on non-convex penalized huberized-SVM

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Journal of Electronic Science and Technology 2024年第1期22卷 81-94页

作者： Peng Wang Ji guo lin-Feng Li School of Finance and Economics Xizang Minzu UniversityXianyang712082China Research Center for Quality Development of Xizang Special Industries Xianyang712082China School of Computer Science and Technology Xinjiang UniversityUrumqi830017China

The support vector machine(SVM)is a classical machine learning *** the hinge loss and least absolute shrinkage and selection operator(LASSO)penalty are usually used in traditional ***,the hinge loss is not differentiable,and the LASSO penalty does not have the Oracle *** this paper,the huberized loss is combined with non-convex penalties to obtain a model that has the advantages of both the computational simplicity and the Oracle property,contributing to higher accuracy than traditional *** is experimentally demonstrated that the two non-convex huberized-SVM methods,smoothly clipped absolute deviation huberized-SVM(SCAD-HSVM)and minimax concave penalty huberized-SVM(MCP-HSVM),outperform the traditional SVM method in terms of the prediction accuracy and classifier *** are also superior in terms of variable selection,especially when there is a high linear correlation between the *** they are applied to the prediction of listed companies,the variables that can affect and predict financial distress are accurately filtered *** all the indicators,the indicators per share have the greatest influence while those of solvency have the weakest *** companies can assess the financial situation with the indicators screened by our algorithm and make an early warning of their possible financial distress in advance with higher precision.

关键词： Huberized loss Machine learning Non-convex penalties Support vector machine(SVM)