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On the Strong Approximation for a Simple Reentrant Line in Light Traffic Under First-buffer First-served Service Discipline

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 823-839页

作者： Kai-ming YANG yong-jiang GUO School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

For a 2-station and 3-class reentrant line under first-buffer first-served(FBFS)service discipline in light traffic,we firstly construct the strong approximations for performance measures including the queue length,workload,busy time and idle time processes.Based on the obtained strong approximations,we use a strong approximation method to find all the law of the iterated logarithms(LILs)for the above four performance measures,which are expressed as some functions of system parameters:means and variances of interarrival and service times,and characterize the fluctuations around their fluid approximations.

关键词： reentrant line queueing network FBFS service discipline strong approximation LIL Brownian motion

Variability Analysis for a Two-station Queueing Network in Heavy Traffic with Arrival Processes Driven by Queues

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 445-466页

作者： Jian CAO yong-jiang GUO Kai-ming YANG School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

The law of the iterated logarithm(LIL)for the performance measures of a two-station queueing network with arrivals modulated by independent queues is developed by a strong approximation method.For convenience,two arrival processes modulated by queues comprise the external system,all others are belong to the internal system.It is well known that the exogenous arrival has a great influence on the asymptotic variability of performance measures in queues.For the considered queueing network in heavy traffic,we get all the LILs for the queue length,workload,busy time,idle time and departure processes,and present them by some simple functions of the primitive data.The LILs tell us some interesting insights,such as,the LILs of busy and idle times are zero and they reflect a small variability around their fluid approximations,the LIL of departure has nothing to do with the arrival process,both of the two phenomena well explain the service station’s situation of being busy all the time.The external system shows us a distinguishing effect on the performance measures:an underloaded(overloaded,critically loaded)external system affects the internal system through its arrival(departure,arrival and departure together).In addition,we also get the strong approximation of the network as an auxiliary result.

关键词： two-station queueing network the law of the iterated logarithm(LIL) strong approximation fluid approximation

Developing Core-Shell Nano-Structures in FeCrAl-ODS Ferritic Alloys with the Co-Addition of Ni and Zr

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 364-372页

作者： Wenquan Ding Jieli Ma yong jiang Yiren Wang Huiqun Liu Key Laboratory for Nonferrous Materials of Ministry of Education School of Materials Science and EngineeringCentral South UniversityChangsha410083China National Key Laboratory for Powder Metallurgy Central South UniversityChangsha410083China

A new Ni+Zr co-alloyed FeCrAl-ODS(oxide-dispersion-strengthened)ferritic alloy was fabricated by ball-milling and hot-isostatic-pressing.Using electron microscopy and atom probe tomography,the dispersive formation of high density core-shelled nano-particles of various sizes was confirmed with a common B2-NiAl shell.Among which,median-sized nano-particles(20-50 nm)typically have an Y_(4)Al_(2)O_(9)nano-core of<~20 nm,ultra-fine nano-particles(<~20)nm have an Y_(4)Zr_(3)O_(12)nano-core of<~10 nm,and larger-sized nano-particles(50-100 nm)incorporate an ultra-fine Y_(4)Al_(2)O_(9)nano-core and a few ultra-fine Y_(4)Zr_(3)O_(12)nano-oxides.All these nano-phases were highly coherent with the ferritic matrix.No large Y--Al-O nano-oxides were formed.The total number density of ultra-fine nano-particles was estimated as~2×10^(23)m^(-3)with a mean size of 6.3 nm only,and accordingly,the new alloy achieved an excellent combination of strength and ductility at high temperatures.

关键词： FeCrAl Oxide-dispersion-strengthened(ODS)alloy Mechanical alloying Nano-oxides Core-shell

Ambient electrocatalytic synthesis of urea by co-reduction of NO_(3)^(-) and CO_(2) over graphene-supported In_(2)O_(3)

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Chinese Chemical Letters 2024年第3期35卷 538-543页

作者： Yini Mao yong jiang Hao Liu Yimin jiang Ming Li Wei Su Rongxing He Key Laboratory of Luminescence Analysis and Molecular Sensing(Southwest University) Ministry of EducationCollege of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China Key Laboratory of Beibu Gulf Environment Change and Resources Utilization(Nanning Normal University) Ministry of EducationCollege of Chemistry and Life ScienceNanning Normal UniversityNanning 530000China

Urea plays a vital role in the sustainable development of mankind as it is one of the most important nitrogen fertilizers.Conventional synthesis of urea is accompanied by a high level of energy consumption while electrocatalytic methods suffer from low yields and poor selectivity.Our work achieves efficient synthesis of urea by designing the graphene-In_(2)O_(3)electrocatalysts for the co-activated reduction of nitrate and carbon dioxide,where the formation rate of urea,Faraday efficiency(FE)and carbon selectivity at-0.35 V vs.RHE can reach 357.47μg mg^(-1)h^(-1),10.46%and~100%,respectively.Herein,the key intermediates in the C–N coupling reaction are demonstrated to be*NH_(2)and*CO_(2),which is of novelty compared to previous reports.This work may provide inspiration for subsequent studies on the reaction mechanism of the electrochemical synthesis of urea,as well as theoretical guidance for the sustainable synthesis of some other important chemical substances.

关键词： Graphene-supported In_(2)O_(3) Dispersion effect Efficient C-N coupling Key intermediate Urea

Preoperative neutrophil-to-lymphocyte ratio predicts symptomatic anastomotic leakage in elderly colon cancer patients: Multicenter propensity score-matched analysis

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 438-450页

作者： Chao-Yang Wang Xiao-Long Li Xiao-Long Ma Xiong-Fei Yang yong-yong Liu yong-jiang Yu Department of Clinical Medicine The First Clinical Medical College of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Department of Gastrointestinal Surgery First Hospital of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Department of Clinical Medicine Gansu University of Chinese MedicineLanzhou 730000Gansu ProvinceChina Department of Anorectology Gansu Provincial People’s HospitalLanzhou 730000Gansu ProvinceChina Department of General Surgery The Second Hospital Affiliated to Lanzhou UniversityLanzhou 730000Gansu ProvinceChina

BACKGROUND The neutrophil-to-lymphocyte ratio(NLR),a composite inflammatory biomarker,is associated with the prognosis in patients with colorectal tumors.However,whether the NLR can be used as a predictor of symptomatic postoperative ana-stomotic leakage(AL)in elderly patients with colon cancer is unclear.AIM To assess the role of the NLR in predicting the occurrence of symptomatic AL after surgery in elderly patients with colon cancer.METHODS Data from elderly colon cancer patients who underwent elective radical colectomy with anastomosis at three centers between 2018 and 2022 were retrospectively analyzed.Receiver operating characteristic curve analysis was performed to determine the best predictive cutoff value for the NLR.Twenty-two covariates were matched using a 1:1 propensity score matching method,and univariate and multivariate logistic regression analyses were used to determine risk factors for the development of postoperative AL.RESULTS Of the 577 patients included,36(6.2%)had symptomatic AL.The optimal cutoff value of the NLR for predicting AL was 2.66.After propensity score matching,the incidence of AL was significantly greater in the≥2.66 NLR subgroup than in the<2.66 NLR subgroup(11.5%vs 2.5%;P=0.012).Univariate logistic regression analysis revealed statistically significant correlations between blood transfusion intraoperatively and within 2 d postoper-atively,preoperative albumin concentration,preoperative prognostic nutritional index,and preoperative NLR and AL occurrence(P<0.05);multivariate logistic regression analysis revealed that an NLR≥2.66[odds ratio(OR)=5.51;95%confidence interval(CI):1.50-20.26;P=0.010]and blood transfusion intraoperatively and within 2 d postoperatively(OR=2.52;95%CI:0.88-7.25;P=0.049)were risk factors for the occurrence of symptomatic AL.CONCLUSION A preoperative NLR≥2.66 and blood transfusion intraoperatively and within 2 d postoperatively are associated with a higher incidence of postoperative symptomatic AL in elderly patients with colon cancer.The preoperative NLR

关键词： Colon cancer Anastomotic leak Neutrophil-to-lymphocyte ratio Propensity score-matched

Progress in in-situ electrochemical nuclear magnetic resonance for battery research

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Magnetic Resonance Letters 2024年第2期4卷 13-21页

作者： yong jiang Mengmeng Zhao Zhangquan Peng Guiming Zhong Laboratory of Advanced Spectro-electrochemistry and Li-ion Batteries Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China University of Chinese Academy of Sciences Beijing100049China Tianmu Lake Institute of Advanced Energy Storage Technologies Co. Ltd.Liyang213300China

A thorough understanding of the fundamental electrochemical and chemical processes in batteries is crucial to advancing energy density and power density.However,the characterizations of such processes are complex.In-situ electrochemical nuclear magnetic resonance(EC-NMR)offers the capability to collect real-time data during battery operation,furnishing insights into the local structures and ionic dynamics of materials by monitoring changes in the chemical environment around the nuclei.EC-NMR also has the advantages of being both quantitative and non-destructive.This paper systematically reviews the design of EC-NMR approach,and delves into the applications and progress of EC-NMR concerning battery reaction mechanisms,failure mechanisms,and overall battery systems.The review culminates in a comprehensive summary of the perspective and challenges associated with EC-NMR.

关键词： In-situ NMR Reaction mechanism Failure mechanism Battery systems Ionic dynamics

Regulating the intrinsic electronic structure of carbon nanofibers with high-spin state Ni for sodium storage with high-power density

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Journal of Materials Science & Technology 2024年第4期171卷 16-23页

作者： Zhijia Zhang Gang Xie Yuefang Chen Yanhao Wei Mengmeng Zhang Shulei Chou Yunxiao Wang Yifang Zhang yong jiang School of Materials Science and Engineering Institute of Quantum Materials and DevicesState Key Laboratory of Separation Membrane and Membrane ProcessesTiangong UniversityTianjin 300387China Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China Institute for Superconducting and Electronic Materials University of WollongongWollongongNSW 2522Australia

Carbon nanofibers(CNFs)with high specific surface area show great potential for sodium storage as a hard carbon material.Herein,CNFs anchored with Ni nanoparticles(CNFs/Ni)were prepared through chemical vapor deposition and impregnation reduction methods,in situ growing on the three-dimensional porous copper current collector(3DP-Cu).The coupling effect of high-spin state Ni nanopar-ticles leads to the increase of defect density and the expansion of lattice spacing of CNFs.Meanwhile,the 3DP-Cu ensures a high loading capacity of CNFs and short ion/electron transport channels.As an integral binder-free anode,the 3DP-Cu/CNFs/Ni exhibits excellent electrochemical performance,which demon-strates a high specific capacity with 298.5 mAh g^(-1)at 1000 mA g^(-1)after 1500 cycles,and a high power density with 200 mAh g^(-1)over 1000 cycles at 5000 mA g^(-1).Density functional theory calculation re-sults show that the high-spin state Ni regulates the electronic structure of CNFs,which significantly reduces the adsorption energy for Na^(+)(-2.7 Ev)and thus enables high-rate capability.The regulation of the electronic structure of carbon materials by high-spin state metal provides a new strategy for developing high-power carbonaceous anode materials for sodium-ion batteries.

关键词： Carbon nanofibers Ni nanoparticles High-spin state Sodium-ion batteries Anode materials Density functional theory calculation

Epigenetic regulation of SARS-Cov-2 spike protein modulates cellular viability and nascent RNA transcription in neuronal cells

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Genes & Diseases 2024年第2期11卷 535-538页

作者： Xi Kong Peng Lu Jinyue Zhang Zheng Bao Chenghao Kuang Bingqing Xie Jianhua Peng Ning Ma yong jiang Shigang Yin Laboratory of Neurological Diseases and Brain Function The Affiliated Hospital of Southwest Medical UniversityLuzhouSichuan 646000China Institute of Epigenetics and Brain Science Southwest Medical UniversityLuzhouSichuan 646000China Department of Neurosurgery The Affiliated Hospital of Southwest Medical UniversityLuzhouSichuan 646000China Inflammation and Allergic Diseases Research Unit The Affiliated Hospital of Southwest Medical UniversityLuzhouSichuan 646000China

SARS-CoV-2 has been demonstrated to be highly susceptible to neuron-and glial-like cells,1 but there is no consensus regarding how the virus affects neurons following neuroinvasion.It is therefore unknown if and how SARS-CoV-2 maintains the homeostasis of neuronal cells.Herein,we revealed that the receptor-binding domain(RBD)of the SARS-CoV-2 spike protein acted as an extracellular remodeling component to undermine epigenetic regulation,perturbnascentRNA(nsRNA)transcription,promote mitochondrial biogenesis,and increase cellular viability in SH-SY5Y cells.

关键词： invasion homeostasis maintain

Identification and characterization of camptothecin tailoring enzymes in Nothapodytes tomentosa

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Journal of Integrative Plant Biology 2024年第6期66卷 1158-1169页

作者： Yin Chen Jian-Ping Huang yong-jiang Wang Meng-Ling Tu Junheng Li Bingyan Xu Guoqing Peng Jing Yang Sheng-Xiong Huang State Key Laboratory of Phytochemistry and Plant Resources in West China and Yunnan Key Laboratory of Natural Medicinal Chemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China

Camptothecin is a complex monoterpenoid indole alkaloid with remarkable antitumor activity.Given that two C-10 modified camptothecin derivatives,topotecan and irinotecan,have been approved as potent anticancer agents,there is a critical need for methods to access other aromatic ringfunctionalized congeners(e.g.,C-9,C-10,etc.).However,contemporary methods for chemical oxidation are generally harsh and low-yielding when applied to the camptothecin scaffold,thereby limiting the development of modified derivatives.Reported herein,we have identified four tailoring enzymes responsible for C-9 modifications of camptothecin from Nothapodytes tomentosa,via metabolomic and transcriptomic analysis.These consist of a cytochrome P450(Nt CPT9H)which catalyzes the regioselective oxidation of camptothecin to 9-hydroxycamptothecin,as well as two methyltransferases(Nt OMT1/2,converting 9-hydroxycamptothecin to 9-methoxycamptothecin),and a uridine diphosphate-glycosyltransferase(Nt UGT5,decorating 9-hydroxycamptothecin to9-β-D-glucosyloxycamptothecin).Importantly,the critical residues that contribute to the specific catalytic activity of Nt CPT9H have been elucidated through molecular docking and mutagenesis experiments.This work provides a genetic basis for producing camptothecin derivatives through metabolic engineering.This will hasten the discovery of novel C-9 modified camptothecin derivatives,with profound implications for pharmaceutical manufacture.

关键词： camptothecin biosynthesis enzymatic assay Nothapodytes tomentosa tailoring enzyme transcriptomic analysis