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Journal of Rare Earths 2024年第7期42卷 1298-1303,I0004页

作者： Pei-yu Liao yu-Quan Qi Zhen Li jian-Hua Jia Ming-Liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-Sen UniversityGuangzhou510006China

On account of the complicated magnetic exchange interactions between lanthanide ions,binuclear lanthanide complexes have broad application prospect in the field of single-molecule ***,it is necessary to develop reasonable bridging ligands to manipulate the directional assembly of binuclear lanthanide ***,we selected the macrocyclic ligand L^(N_(8)O_(2))to build up two new dilanthanide complexes[Ln_(2)(LN_(8)O_(2))(OpyO)_(2)(H_(2)O)2](NO_(3))_(2)(1-Ln,Ln=Dy,Tb;LN_(8)O_(2)=hexamethyl-tetraaza-dioxe-dipyrazolacycloicosaphane-2,9,12,19-tetraene;OpyOH=2-pyridinol-1-oxide).Dynamic magnetic studies show that 1-Dy exhibits slow relaxation behavior under a 1 kOe applied *** fitting analysis of relaxation times gives the effective energy barrier of 38.2 cm^(−1),and reveals that the slow magnetic relaxation behavior is dominated by the Orbach and Raman ***-resolution luminescence emission spectrum indicates the energy gap of 36.8 cm^(−1)between the ground state and the first excited state,consistent with the magnetic measurement results.1-Tb exhibits brilliant characteristic green light emission under UV light *** absolute quantum yield of 1-Tb is 44.8%,and its first-order fitted decay lifetime is 779.21μs at room *** study provides the way for directional construction of high-performance molecular materials with magnetic and optical dual-function.

关键词： Dilanthanide complexes Single-molecule magnets Macrocyclic ligand Photoluminescence behavior Rare earths

Exploring changes of precipitation extremes under climate change through global variable-resolution modeling

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Science Bulletin 2024年第2期69卷 237-247页

作者： Wei Sun jian Li Rucong yu Nina Li Yi Zhang State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Institute of Tibetan Plateau Meteorology China Meteorological AdministrationChengdu 610072China Department of Atmospheric Science Yunnan UniversityKunming 650091China National Meteorological Center China Meteorological AdministrationBeijing 100081China 2035 Future Laboratory PIESAT Information Technology Co.Ltd.Beijing 100105China

Understanding the responses of precipitation extremes to global climate change remains limited owing to their poor representations in models and complicated interactions with multi-scale *** we take the record-breaking precipitation over China in 2021 as an example,and study its changes under three different climate scenarios through a developed pseudo-global-warming(PGW)experimental framework with 60-3 km variable-resolution global ensemble *** to the present climate,the precipitation extreme under a warmer(cooler)climate increased(decreased)in intensity,coverage,and total amount at a range of 24.3%-37.8%(18.7%-56.1%).With the help of the proposed PGW experimental framework,we further reveal the impacts of the multi-scale system interactions in climate change on the precipitation *** the warmer climate,large-scale water vapor transport converged from double typhoons and the subtropical high marched into central China,enhancing the convective energy and instability on the leading edge of the transport *** a result,the mesoscale convective system(Mcs)that directly contributed to the precipitation extreme became stronger than that in the present *** the contrary,the cooler climate displayed opposite changing characteristics relative to the warmer climate,ranging from the large-scale systems to local environments and to the *** summary,our study provides a promising approach to scientifically assess the response of precipitation extremes to climate change,making it feasible to perform ensemble simulations while investigating the multi-scale system interactions over the globe.

关键词： Precipitation extreme Climate change Pseudo-global-warming experiment Variable-resolution modeling Multi-scale system interaction

Promoted surface charge density from interlayer Zn–N_(4) configuration in carbon nitride for enhanced CO_(2) photoreduction

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Nano Research 2024年第4期17卷 2400-2409页

作者： Xianjin shi yu Huang Gangqiang Zhu Wei Peng Meijuan Chen State Key Laboratory of Loess and Quaternary Geology(SKLLQG) Key Laboratory of Aerosol Chemistry and PhysicsInstitute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Center of Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi’an 710061China University of Chinese Academy of Sciences Beijing 100049China School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710062China School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710049China

The solar-driven reduction of CO_(2) into valuable products is a promising method to alleviate global environmental problems and energy ***,the low surface charge density limits the photocatalytic conversion performance of CO_(2).Herein,a polymeric carbon nitride(PCN)photocatalyst with Zn single atoms(Zn1/CN)was designed and synthesized for CO_(2) *** results of the CO_(2) photoreduction studies show that the CO and CH_(4) yields of Zn1/CN increased fivefold,reaching 76.9 and 22.9μmol/(g·h),respectively,in contrast to the unmodified ***+plasma-etched X-ray photoelectron spectroscopy and synchrotron radiation-based X-ray absorption fine structure results reveal that Zn single atom is mainly present in the interlayer space of PCN in the Zn–N_(4) *** characterizations indicate that the interlayer Zn–N_(4) configuration can amplify light absorption and establish an interlayer charge transfer ***-assisted Kelvin probe force microscopy confirms that more photogenerated electrons are delivered to the catalyst surface through interlayer Zn–N_(4) configuration,which increases its surface charge ***,in-situ infrared spectroscopy combined with density functional theory calculation reveals that promoted surface charge density accelerates key intermediates(*COOH)conversion,thus achieving efficient CO_(2) *** work elucidates the role of internal single atoms in catalytic surface reactions,which provides important implications for the design of single-atom catalysts.

关键词： single-atom catalysts photocatalytic CO_(2)reduction interlayer modification charge transfer dynamics surface charge density

Immunomodulation of adipose-derived mesenchymal stem cells on peripheral blood mononuclear cells in colorectal cancer patients with COVID-19

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2113-2122页

作者： Jun-Feng Wang Xiao-Xia Yang jian Zhang Yan Zheng Fu-Qing Zhang Xiao-Feng shi yu-Liang Wang Department of Colorectal Oncology Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerTianjin’s Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjin 300060China Department of Neurology Tianjin First Center HospitalTianjin 300192China Prosthodontics Studio Tianjin Stomatological HospitalTianjin 300041China Department of Clinical Laboratory Medicine Tianjin Institute of UrologyThe Second Hospital of Tianjin Medical UniversityTianjin 300211China Department of Emergency Tianjin First Central HospitalTianjin 300192China

BACKGROUND Accumulating evidence has shown that adipose tissue-derived mesenchymal stem cells(ADSCs)are an effective therapeutic approach for managing coronavirus disease 2019(COVID-19);however,further elucidation is required to determine their underlying immunomodulatory effect on the mRNA expression of T helper cell-related transcription factors(TFs)and cytokine release in peripheral blood mononuclear cells(PBMCs).AIM To investigate the impact of ADSCs on the mRNA expression of TFs and cytokine release in PBMCs from colorectal cancer(CRC)patients with severe COVID-19(CRC^(+)patients).METHODS PBMCs from CRC^(+)patients(PBMCs-C+)and age-matched CRC patients(PBMCs-C)were stimulated and cultured in the presence/absence of *** mRNA levels of T-box TF TBX21(T-bet),GATA binding protein 3(GATA-3),RAR-related orphan receptor C(RORC),and forkhead box P3(FoxP3)in the PBMCs were determined by reverse transcriptase-polymerase chain *** supernatants were evaluated for levels of interferon gamma(IFN-γ),interleukin 4(IL-4),IL-17A,and transforming growth factor beta 1(TGF-β1)using an enzyme-linked immunosorbent *** Compared with PBMCs-C,PBMCs-C+exhibited higher mRNA levels of T-bet and RORC,and increased levels of IFN-γ and ***,a significant decrease in FoxP3 mRNA and TGF-β1,as well as an increase in Tbet/GATA-3,RORC/FoxP3,IFN-γ/IL-4,and IL-17A/TGF-β1 ratios were observed in PBMCs-C+.Furthermore,ADSCs significantly induced a functional regulatory T cell(Treg)subset,as evidenced by an increase in FoxP3 mRNA and TGF-β1 release *** was accompanied by a significant decrease in the mRNA levels of T-bet and RORC,release of IFN-γ and IL-17A,and T-bet/GATA-3,RORC/FoxP3,IFN-γ/IL-4,and IL-17A/TGF-β1 ratios,compared with the PBMCs-C+*** The present in vitro studies showed that ADSCs contributed to the immunosuppressive effects on PBMCs-C+,favoring Treg ***,ADSC-based cell therapy could be a beneficial approach for p

关键词： Colorectal cancer COVID-19 Adipose-derived mesenchymal stem cells T helper cell Immunomodulation

Learning-based counterfactual explanations for recommendation

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Science China(Information Sciences) 2024年第8期67卷 115-129页

作者： Jingxuan WEN Huafeng LIU Liping JING jian yu School of Computer and Information Technology Beijing Jiaotong University Beijing Key Lab of Traffic Data Analysis and Mining Beijing Jiaotong University

Counterfactual explanations provide explanations by exploring the changes in effect caused by changes in cause. They have attracted significant attention in recommender system research to explore the impact of changes in certain properties on the recommendation mechanism. Among several counterfactual recommendation methods, item-based counterfactual explanation methods have attracted considerable attention because of their flexibility. The core idea of item-based counterfactual explanation methods is to find a minimal subset of interacted items(i.e., short length) such that the recommended item would topple out of the top-K recommendation list once these items have been removed from user interactions(i.e., good quality). Usually, explanations are generated by ranking the precomputed importance of items, which fails to characterize the true importance of interacted items due to separation from the explanation generation. Additionally, the final explanations are generated according to a certain search strategy given the precomputed importance. This indicates that the quality and length of counterfactual explanations are deterministic;therefore, they cannot be balanced once the search strategy is fixed. To overcome these obstacles, this study proposes learning-based counterfactual explanations for recommendation(LCER) to provide counterfactual explanations based on personalized recommendations by jointly modeling the factual and counterfactual preference. To achieve consistency between the computation of importance and generation of counterfactual explanations, the proposed LCER endows an optimizable importance for each interacted item, which is supervised by the goal of counterfactual explanations to guarantee its credibility. Because of the model's flexibility, the trade-off between quality and length can be customized by setting different proportions. The experimental results on four real-world datasets demonstrate the effectiveness of the proposed LCER over several

关键词： recommender system explainable recommendation item-based explanation counterfactual inference counterfactual explanation

Interaction Mechanisms between Natural Debris Flow and Rigid Barrier Deflectors:A New Perspective for Rational Design and Optimal Arrangement

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1679-1699页

作者： yu Huang Beilei Liu Dianlei Feng Hao shi Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai200092China Department of Hydraulic Engineering College of Civil EngineeringTongji UniversityShanghai200092China

Rigid barrier deflectors can effectively prevent overspilling landslides,and can satisfy disaster prevention ***,the mechanisms of interaction between natural granular flow and rigid barrier deflectors require further *** date,few studies have investigated the impact of deflectors on controlling viscous debris flows for geological disaster *** investigate the effect of rigid barrier deflectors on impact mechanisms,a numerical model using the smoothed particle hydrodynamics(SPH)method with the Herschel–Bulkley model is proposed to simulate the interaction between natural viscous flow and single/dual barriers with and without *** model was validated using laboratory flume test data from the ***,the model was used to investigate the influence of the deflector angle and multi-barrier *** optimal configuration of multi-barriers was analyzed with consideration to the barrier height and distance between the barriers,because these metrics have a significant impact on the viscous flow pile-up,run-up,and overflow *** investigation considered the energy dissipation process,retention efficiency,and dead-zone *** with bare barriers with similar geometric characteristics and spatial distribution,rigid barriers with deflectors exhibit superior effectiveness in preventing the overflow and overspilling of viscous debris *** for the rational design of deflectors and the optimal arrangement of multi-barriers are provided to mitigate geological disasters.

关键词： Rigid barrier deflectors deflector angle single-barrier dual-barrier arrangements viscous debris flow over-spilling delta-plus-SPH

CP violation of baryon decays with Nπrescatterings

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Chinese Physics C 2024年第10期48卷 1-10页

作者： jian-Peng Wang Fu-Sheng yu MOE Frontiers Science Center for Rare Isotopes and School of Nuclear Science and TechnologyLanzhou UniversityLanzhou 730000China

There is a long-standing puzzle that the CP violation(CPV)in the baryon systems has never been wellestablished in experiments,while the CPV of mesons have been observed by *** this paper,we propose thatthe CpV of baryon decays can be generated with the rescatterings of a nucleon and a pion into some final states,i.e Nπ→Nπor Nππ.Benelited by the fruitful data of Nπscatterings,we can model-independently analyse the strongphases of b-baryon decays using the partial wave amplitudes of Nπ*** the most difficult problemof non-perturbative dynamics,it makes a great advantage to predict the CpV of baryon decays with a relatively *** understanding of the decay *** study the processes of∧_(b)^(0)→(pπ^(+)π^(-))h^(-)and(pπ^(0))h^(-)with h=πor *** is found that the global CPV of the above processes in the invariant mass regions of Nπscatterings are at theorder of several *** importantly,the local CPV in some regions of the Dalitz plots can reach the order of 10%,or be even *** the predicted results and the experimental data samples,we strong suggest tomeasure the CPV of∧_(b)^(0)→(pπ^(+)π^(-))K^(-),which has a large possibility to achieve the first observation of CPV in thebaryon system.

关键词： CP violation baryon decays Nπscatterings

Autonomous navigation of an asteroid orbiter enhanced by a beacon satellite in a high-altitude orbit

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Astrodynamics 2024年第3期8卷 375-400页

作者： Weidong Yin yu shi Leizheng Shu Yang Gao University of Chinese Academy of Sciences Beijing100049China Key Laboratory of Space Utilization Technology and Engineering Center for Space UtilizationChinese Academy of SciencesBeijing100094China

This study aims to assess the autonomous navigation performance of an asteroid orbiter enhanced using an inter-satellite link to a beacon *** navigation includes the orbit determination of the orbiter and beacon,and asteroid gravity estimation without any ground station *** measurements were acquired using satellite-to-satellite tracking(SST)and optical observation of asteroid surface *** study presents a new orbiter-beacon SST scheme,in which the orbiter circumnavigates the asteroid in a low-altitude strongly-perturbed orbit,and the beacon remains in a high-altitude weakly-perturbed *** used Asteroid 433 Eros as an example,and analyzed and designed low-and high-altitude orbits for the orbiter and *** navigation measurements were precisely modeled,extended Kalman filters were devised,and observation configuration was analyzed using the Cramer-Rao lower bound(CRLB).Monte Carlo simulations were carried out to assess the effects of the orbital inclination and altitudes of the orbiter and beacon as key influencing *** simulation results showed that the proposed SST scheme was an effective solution for enhancing the autonomous navigation performance of the orbiter,particularly for improving the accuracy of gravity estimation.

关键词： asteroid exploration gravity estimation orbit determination satellite-to-satellite tracking(SST) optical observation

AWeb Application Fingerprint Recognition Method Based on Machine Learning

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 887-906页

作者： Yanmei shi Wei yu Yanxia Zhao yungang Jia School of Integrated Circuit Science and Engineering Tianjin University of TechnologyTianjin300382China College of International Business Zhejiang Yuexiu UniversityShaoxing312030China School of Public Administration Zhejiang Gongshang UniversityHangzhou310018China Tianjin Branch of National Computer Network Emergency Response Technical Team/Coordination Center of China Tianjin300100China

Web application fingerprint recognition is an effective security technology designed to identify and classify web applications,thereby enhancing the detection of potential threats and *** fingerprint recognition methods,which rely on preannotated feature matching,face inherent limitations due to the ever-evolving nature and diverse landscape of web *** response to these challenges,this work proposes an innovative web application fingerprint recognition method founded on clustering *** method involves extensive data collection from the Tranco List,employing adjusted feature selection built upon Wappalyzer and noise reduction through truncated SVD dimensionality *** core of the methodology lies in the application of the unsupervised OPTICS clustering algorithm,eliminating the need for preannotated *** transforming web applications into feature vectors and leveraging clustering algorithms,our approach accurately categorizes diverse web applications,providing comprehensive and precise fingerprint *** experimental results,which are obtained on a dataset featuring various web application types,affirm the efficacy of the method,demonstrating its ability to achieve high accuracy and broad *** novel approach not only distinguishes between different web application types effectively but also demonstrates superiority in terms of classification accuracy and coverage,offering a robust solution to the challenges of web application fingerprint recognition.

关键词： Web application fingerprint recognition unsupervised learning clustering algorithm feature extraction automated testing network security

Computer-aided molecular design and optimization of potent inhibitors disrupting APC-Asef interaction

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2631-2645页

作者： Xuefei Wang Zeqian Du yuegui Guo Jie Zhong Kun Song Junyuan Wang jianqiang yu Xiuyan Yang Chen-Ying Liu Ting shi jian Zhang Department of Pathophysiology Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of EducationShanghai Jiao Tong UniversitySchool of MedicineShanghai 200025China Key Laboratory of Protection Development and Utilization of Medicinal Resources in Liupanshan AreaMinistry of EducationPeptide&Protein Drug Research CenterSchool of PharmacyNingxia Medical UniversityYinchuan 750004China State Key Laboratory of Microbial Metabolism Joint International Research Laboratory of Metabolic and Developmental SciencesSchool of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China Department of Colorectal and Anal Surgery Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Basic Science Research Center Base(Pharmaceutical Science) Yantai UniversityYantai 264005China Medicinal Chemistry and Bioinformatics Center Shanghai Jiao Tong UniversitySchool of MedicineShanghai 200025China State Key Laboratory of Pharmaceutical Biotechnology Nanjing UniversityNanjing 210023China

Colorectal cancer(CRC)is the second leading cause of cancer mortality *** initial diagnosis,approximately 20%of patients are diagnosed with metastatic CRC(mCRC).Although the APC-Asef interaction is a well-established target for mCRC therapy,the discovery and development of effective and safe drugs for mCRC patients remains an urgent and challenging *** this study,we identified a novel structural scaffold based on MAI inhibitors,the first-in-class APC-Asef inhibitors we reported *** model-driven optimizations of the N-terminal cap and experimental evaluations of inhibitory activity were performed,and 24-fold greater potency was obtained with the best inhibitor compared to the parental *** addition,the cocrystal structure validated that the two-layerπ-πstacking interactions were essential for inhibitor stabilization in the bound ***,in vitro and in vivo studies have demonstrated that novel inhibitors suppressed lung metastasis in CRC by disrupting the APC-Asef *** results provide an intrinsic structural basis to further explore drug-like molecules for APC-Asef-mediated CRC therapy.

关键词： APC-Asef Peptidomimetic Computer-aided molecular design ONIOM model π-πstacking Metastatic colorectal cancer