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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

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

Flexible 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 flexible 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 flexibility 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 Flexible 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

Carbapenem-resistant Klebsiella pneumoniae infections after liver transplantation:Drug resistance,risk factors and impact on prognosis

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World Journal of Gastroenterology 2025年第8期31卷 38-48页

作者： Tao-Hua Liu Li-Hua Chen qi-Quan Wan Department of Pediatrics The Third Xiangya Hospital of Central South UniversityChangsha 410013Hunan ProvinceChina Department of Laboratory Medicine The Third Xiangya Hospital of Central South UniversityChangsha 410013Hunan ProvinceChina Department of Transplant Surgery The Third Xiangya Hospital of Central South UniversityChangsha 410013Hunan ProvinceChina Engineering and Technology Research Center for Transplantation Medicine of National Health Commission The Third Xiangya Hospital of Central South UniversityChangsha 410013Hunan ProvinceChina

bACKGROUND Liver transplant(LT)recipients are susceptible to carbapenem-resistant Klebsiella pneumoniae(CRKP)*** research addressing the incidence,timing,infection sites,resistance patterns,treatment options,and associated risk factors among LT recipients with CRKP is now *** To assess the incidence,resistance,therapy,and risk factors of CRKP infections post-LT,and to evaluate the impact of them on *** A retrospective study was conducted,including 430 consecutive patients who underwent LT between January 2015 and June *** study aimed to investigate the risk factors for CRKP infections and their influence on outcomes using logistic regression *** Among the 430 patients who underwent LT,20(4.7%)experienced at least one documented CRKP infection within 3 months *** median time from LT to the onset of CRKP infections was 6.5 *** lungs and bloodstream were the most common sites of CRKP *** isolates were relatively susceptible to ceftazidime/avibactam(93.7%),polymyxin b(90.6%),and tigecycline(75.0%)***,all isolates were resistant to piperacillin/tazobactam,ceftazidime,cefepime,aztreonam,meropenem,and levofloxacin *** with CRKP infections had a mortality rate of 35%,the rate was 12.5%for those receiving ceftazidime/avibactam *** analysis identified female sex[odds ratio(OR)=3.306;95%confidence interval(CI):1.239-8.822;P=0.017],intraoperative bleeding≥3000 mL(OR=3.269;95%CI:1.018-10.490;P=0.047),alanine aminotransferase on day 1 post-LT≥1500 U/L(OR=4.370;95%CI:1.686-11.326;P=0.002),and post-LT mechanical ventilation(OR=2.772;95%CI:1.077-7.135;P=0.035)as significant variables associated with *** infections were related to an intensive care unit length(ICU)of stay≥7 days and 6-month all-cause mortality *** CRKP infections were frequent complications following LT,with poor associated *** factors for p

关键词： Liver transplantation Carbapenem-resistant Klebsiella pneumonia Antibiotic resistance Infection Immunosuppression Risk factors

Neural-based prescribed-time consensus control for multiagent systems via dynamic memory event-triggered mechanism

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Science China Technological Sciences 2025年第3期68卷 221-231页

作者： Xiaohong ZHENG Hui MA qi ZHOU Hongyi LI School of Automation Guangdong-Hong Kong Joint Laboratory for Intelligent Decision and Cooperative Control and Guangdong Provincial Key Laboratory for Intelligent Decision and Cooperative Control Guangdong University of Technology School of Mathematics and Statistics Guangdong University of Technology College of Electronic and Information Engineering and the Chongqing Key Laboratory of Generic Technology and System of Service Robots Southwest University

This work investigates the implementation of distributed prescribed-time neural network(NN) control for nonlinear multiagent systems(MASs) using a dynamic memory event-triggered mechanism(DMETM). First, it introduces a composite learning technique in NN control. This method leverages the prediction error within the NN update law to enhance the accuracy of the unknown nonlinearity estimation. Subsequently, by introducing a time-varying transformation, the study establishes a distributed prescribed-time control algorithm. The notable feature of this algorithm is its ability to predetermine the convergence time independently of initial conditions or control parameters. Moreover, the DMETM is established to reduce the actuation frequency of the controller. Unlike the conventional memoryless dynamic event-triggered mechanism, the DMETM incorporates a memory term to further increase triggering intervals. Utilizing a distributed estimator for the leader, the DMETM-based NN prescribed-time controller is designed in a fully distributed manner, which guarantees that all signals in the closed-loop system remain bounded within the prescribed time. Finally, simulation results are presented to validate the effectiveness of the proposed algorithm.

关键词： consensus control composite learning control dynamic memory event-triggered control prescribed-time control multiagent systems (MASs)

Support effect and confinement effect of porous carbon loaded tin dioxide nanoparticles in high-performance CO_(2) electroreduction towards formate

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Chinese Chemical Letters 2025年第1期36卷 597-602页

作者： Xingxing Jiang Yuxin Zhao Yan Kong Jianju Sun Shangzhao Feng Xin Lu qi Hu Hengpan Yang Chuanxin He College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Leveraging the interplay between the metal component and the supporting material represents a cornerstone strategy for augmenting electrocatalytic efficiency,e.g.,electrocatalytic CO_(2)reduction reaction(CO_(2)RR).Herein,we employ freestanding porous carbon fibers(PCNF)as an efficacious and stable support for the uniformly distributed SnO_(2)nanoparticles(SnO_(2)PCNF),thereby capitalizing on the synergistic support effect that arises from their strong *** one hand,the interaction between the SnO_(2)nanoparticles and the carbon support optimizes the electronic configuration of the active *** interaction leads to a noteworthy shift of the d-band center toward stronger intermediate adsorption energy,consequently lowering the energy barrier associated with CO_(2)*** a result,the Sn O_(2)PCNF realizes a remarkable CO_(2)RR performance with excellent selectivity towards formate(98.1%).On the other hand,the porous carbon fibers enable the uniform and stable dispersion of SnO_(2)nanoparticles,and this superior porous structure of carbon supports can also facilitate the exposure of the SnO_(2)nanoparticles on the reaction interface to a great ***,adequate contact between active sites,reactants,and electrolytes can significantly increase the metal utilization,eventually bringing forth a remarkable7.09 A/mg mass *** work might provide a useful idea for improving the utilization rate of metals in numerous electrocatalytic reactions.

关键词： CO_(2)electroreduction Support effect Porous carbon fiber Formate Mass activity