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New Taub-NUT black holes with massive spin-2 hair

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 51-58页

作者： Yu-qi Chen Hai-Shan Liu Center for Joint Quantum Studies and Department of Physics School of ScienceTianjin UniversityTianjin 300350China

We consider Einstein gravity extended with quadratic curvature invariants,within which the well-known Ricci-flat Taub-NUT black hole remains a *** analysis of the unstable Lichnerowicz modes in the Taub-NUT background enables us to identify the mass and NUT parameters(m,n)where new Taub-NUT black holes can *** then adopt numerical techniques to construct these new Taub-NUT black holes,which bifurcate away from the Ricci-flat *** the Ricci-flat Taub-NUT,there can exist two new black holes for an appropriate given temperature,making it a total of three if we include the Ricci-flat one.

关键词： higher derivative gravity black hole solution Taub-NUT spacetime

Upper bounds on the Multicolor Ramsey Numbers r_(k)(C_(4))

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 286-294页

作者： Tian-yu LI qi-zhong LIN Center for Discrete Mathematics Fuzhou UniversityFuzhou 350108China

The multicolor Ramsey number r_(k)(C_(4))is the smallest integer N such that any k-edge coloring of KN contains a monochromatic C_(4).The current best upper bound of r_(k)(C_(4))was obtained by Chung(1974)and independently by Irving(1974),i.e.,r_(k)(C_(4))≤k^(2)+k+1 for all k≥*** is no progress on the upper bound since *** this paper,we improve the upper bound of r_(k)(C_(4))by showing that r_(k)(C_(4))≤k^(2)+k-1 for even k≥*** improvement is based on the upper bound of the Turan number ex(n,C4),in which we mainly use the double counting method and many novel ideas from Firke,Kosek,Nash,and Williford[***,Ser.b 103(2013),327-336].

关键词： Multicolor Ramsey number Turan number 4-cycle

Solid-state synthesis of mesoporous metals via mechanochemical coordination self-assembly

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Science China Chemistry 2025年第2期68卷 492-498页

作者： Hailong xiong Chunyu qi Lantian xue Ling Zhang Hanyu Liu Zhen-An qiao State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130012China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China State Key Laboratory of Superhard Materials College of PhysicsJilin UniversityChangchun 130012China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

Mesoporous metals with large surface area,high pore volume,and uniform pore structure hold excellent advantages for various ***,the state-of-the-art synthesis methods are still limited to wet chemistry,which requires excessive solvents and a time-consuming drying ***,we report a facile and general mechanochemical coordination self-assembly strategy to prepare mesoporous metals(e.g.,Rh,Ru,Ir,Pt,Pd,Ag,Co,and Ni)with remarkable porous properties by using metal chlorides and cationic polymer *** with the wet chemistry process,this method proceeds without solvents and does not need complicated experimental conditions and long synthetic periods,which not only greatly reduces the consumption of cost and energy and environmental pollution,but also improves the synthesis efficiency and yield of target *** believe the developed approach will provide a general pathway for the scalable preparation of advanced porous materials.

关键词： mechanochemistry self-assembly mesoporous materials mesoporous metals electrocatalysis

Auxiliary-field Monte Carlo method for frustrated spin systems

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Chinese Physics b 2025年第2期34卷 118-122页

作者： Ning Cai Yuan Gao Wei Li Yang qi State Key Laboratory of Surface Physics and Department of Physics Fudan UniversityShanghai 200433China School of Physics Beihang UniversityBeijing 100191China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China

We extend a semiclassical numerical method, bosonic auxiliary-field Monte Carlo, to quantum spin systems. This method breaks the lattice into clusters, solves each cluster precisely and couples them with classical auxiliary fields through classical Monte Carlo simulation. We test the method with antiferromagnetic spin models in one-dimensional chains, square lattices and triangular lattices, and obtain reasonable results at finite temperatures. This algorithm builds a bridge between classical Monte Carlo method and quantum methods. The algorithm can be improved with either progress in classical Monte Carlo sampling or the development of quantum solvers, and can also be further applied to systems with different lattices or interactions.

关键词： Monte Carlo quantum many-body system frustrated magnets

Advancements and challenges in esophageal carcinoma prognostic models:A comprehensive review and future directions

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World Journal of Gastrointestinal Oncology 2025年第2期17卷 311-314页

作者： Jia Chen qi-Chang xing Department of Clinical Pharmacy Xiangtan Central HospitalXiangtan 411100Hunan ProvinceChina The Affiliated Hospital Hunan UniversityChangsha 410082Hunan ProvinceChina

In this article,we comment on the article published by Yu et *** employing LASSO regression and Cox proportional hazard models,the article identified nine significant variables affecting survival,including body mass index,Karnofsky performance status,and tumor-node-metastasis *** firmly concur with Yu et al regarding the vital significance of clinical prediction models(CPMs),including logistic regression and Cox regression for assessment in esophageal carcinoma(EC).However,the nomogram's limitations and the complexities of integrating genetic factors pose *** integration of immunological data with advanced statistics offers new research ***-throughput sequencing and big data,facilitated by machine learning,have revolutionized cancer research but require substantial computational *** future of CPMs in EC depends on leveraging these technologies to improve predictive accuracy and clinical application,addressing the need for larger datasets,patientreported outcomes,and regular updates for clinical relevance.

关键词： Predictive model Machine learning Esophageal carcinoma Survival rate Factors

Electronic modulation induced by coupling RuO2 with electron-donating Co3O4 for high-active and long-life rechargeable Zn-air batteries

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Journal of Energy Chemistry 2025年第2期101卷 99-109页

作者： xuena Ma Zhangxin xu Mingyang Liu Panzhe qiao qi Li Ruihong Wang baojiang Jiang Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People's Republic of China School of Chemistry and Materials ScienceHeilongjiang University Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences

Electronic-state modulation strategy offers great potential in designing RuO2-based bifunctionalelectrocatalysts for rechargeable Zn-air batteries（ZAbs）.Various three-dimensional（3D） transition metal oxides are attempted to couple with RuO2for constructing an appropriate Ru—O—M *** work aims to construct Co3O4-RuO2heterostructures on carbon sheets（Co3O4/RuO2/NCNS） for boosting electronic transfer and *** and theoretical calculations identify the electronic transfer from Co3O4to RuO2that modulates the electronic structure of metal surfaces/***,it leads to the increase in Co3+content,electron-rich state at RuO2surface and electronic accumulation at ***,this electronic-state modulation optimizes the d-band center in Co3O4/RuO2that lowers the reaction barriers and endows interfaces as the biggest contributor to oxygen reduction reaction（ORR） and oxygen evolution reaction（OER） performance,The Co3O4/RuO2/NCNS shows a quite low potential difference of 0.62 V and remarkable durability for ORR/***3O4/RuO2/NCNS-assembled ZAbs exhibit an excellent specific capacity of 818.3 mA h g-1and a superior lifespan over 750 h.

关键词： Charge-discharge stability Co3O4-RuO2 heterostructure Electronic modulation Reaction energy barrier Zn-air battery

Gut microbiota shifts in hepatitis b-related portal hypertension after transjugular intrahepatic portosystemic shunt:Mechanistic and clinical implications

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World Journal of Gastroenterology 2025年第3期31卷 134-137页

作者： qi-Rong Jiang Da-Wu Zeng Department of Hepatology Hepatology Research InstituteThe First Affiliated HospitalFujian Medical UniversityFuzhou 350005Fujian ProvinceChina Department of Infectious Diseases The First Affiliated Hospital of Fujian Medical UniversityFuzhou 350004Fujian ProvinceChina

In this article,we provide commentary on the recent article by Zhao et *** focus on the shifts in the gut microbiota of patients with hepatitis b virus(HbV)-associated cirrhosis/portal hypertension(PH)following transjugular intrahepatic portosystemic shunt(TIPS)and the implications for understanding the mechanisms,diagnosis,and *** comparing the gut microbiota composition and dynamic changes before and after TIPS in patients with and without hepatic encephalopathy,the authors found an increase in non-probiotic bacteria in those who developed hepatic encephalopathy post-TIPS,with Morganella species present only in the hepatic encephalopathy *** gut microbiota changes post-TIPS among patients without the occurrence of hepatic encephalopathy suggest potential therapeutic benefits through prophylactic microbiome ***,the specific gut microbiota alterations may hold promise to predict the risk of hepatic encephalopathy in individuals undergoing TIPS for HbVrelated *** these promising findings,future studies are needed to address limitations,including a small sample size,a relatively short evaluation period for gut microbiota alterations,the absence of data on dynamic alterations in gut microbiota post-TIPS and their correlation with blood ammonia levels,and the lack of validation in animal *** conclusion,Zhao et al's study has shed new light on the link of gut microbiota with post-TIPS hepatic encephalopathy,potentially through the intricate gut-liver axis,and has important clinical implications for improving the management of patients with HbV-related PH.

关键词： Hepatitis b virus Cirrhosis Portal hypertension Hepatic encephalopathy Transjugular intrahepatic portosystemic shunt Gut microbiota

Flex.b.e molecules dedicate to release strain of inverted inorganic perovskite solar cell

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Journal of Energy Chemistry 2025年第1期100卷 87-93页

作者： Hongrui Sun Sanlong Wang Pengyang Wang Yali Liu Shanshan qi biao Shi Ying Zhao xiaodan Zhang Institute of Photoelectronic Thin Film Devices and Technology Renewable Energy Conversion and Storage CenterState Key Laboratory of Photovoltaic Materials and CellsNankai UniversityTianjin 300350China Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin Tianjin 300350China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Engineering Research Center of Thin Film Photoelectronic Technology of Ministry of Education Tianjin 300350China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China

The tensile strain in inorganic perovskite films induced by thermal annealing is one of the primary factors contributing to the inefficiency and instability of inorganic perovskite solar cells(IPSCs),which reduces the defect formation ***,a flex.b.e molecule 5-maleimidovaleric acid(5-MVA)was introduced as a strain buffer to release the residual strain of CsPbI_(2.85)br_(0.15)*** anhydride and carboxyl groups in 5-MVA interact strongly with the uncoordinated Pb^(2+)through Lewis acid-base reaction,thus tightly“pull”the perovskite *** in-between soft carbon chain increased the structural flex.b.lity of CsPbI_(2.85)br_(0.15)perovskite materials,which effectively relieved the intrinsic internal strain of CsPbI_(2.85)br_(0.15),resisted the corrosion of external strain,and also reduced the formation of defects such as VIand *** addition,the introduction of 5-MVA improved crystal quality,passivated residual defects,and narrowed energy level ***,power conversion efficiency(PCE)of NiOxbased inverted IPSCs increased from 19.25%to 20.82%with the open-circuit voltage enhanced from 1.164 V to 1.230 *** release of strain also improved the stability of CsPbI_(2.85)br_(0.15)perovskite films and devices.

关键词： Inverted inorganic perovskite solar cells Flex.b.e molecules Strain release Crystallization Energy barrier High PCE

Fast and robust production of quantum superposition states by the fractional shortcut to adiabaticity

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Communications in Theoretical Physics 2025年第1期77卷 54-64页

作者： Guan-qiang Li Hao Guo Yu-qi Zhang bo Yang Ping Peng Department of Physics and Institute of Theoretical Physics Shaanxi University of Science and TechnologyXi'an 710021China

The fractional shortcut to adiabaticity(f-STA)for the production of quantum superposition states is proposed firstly via a three-level system with aΛ-type linkage pattern and a four-level system with a tripod *** fast and robust production of the coherent superposition states is studied by comparing the populations for the f-STA and the fractional stimulated Raman adiabatic passage(f-STIRAP).The states with equal proportions can be produced by fixing the controllable parameters of the driving pulses at the final moment of the whole *** effects of the pulse intensity and the time delay of the pulses on the production process are discussed by monitoring the populations on all of the quantum *** particular,the spontaneous emission arising from the intermediate state is investigated by the quantum master *** result reveals that the f-STA exhibits superior advantages over the f-STIRAP in producing the superposition states.

关键词： quantum population transfer shortcut to adiabaticity coherent superposition states dark states spontaneous emission