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Non-uniform Berry-Esseen bound by unbounded exchangeable pairs approach

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Applied Mathematics(A Journal of Chinese Universities) 2021年第2期36卷 256-268页

作者： liU Da-li Li Zheng WANG Han-chao CHEN Zeng-jing Institute for Financial Studies Shandong UniversityJinan 250100China School of Mathematics Shandong UniversityJinan 250100China

In this paper,a new technique is introduced to obtain non-uniform Berry-Esseen bounds for normal and nonnormal approximations by unbounded exchangeable pairs.This technique does not rely on the concentration inequalit... 详细信息

关键词： non-uniform Berry-Esseen bounds Stein's method exchangeable pairs

The feasibility of leadless pacemaker implantation in nonagenarians:case report and literature review

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Journal of Geriatric Cardiology 2022年第8期19卷 626-630页

作者： Chun-ling zheng li ZHAO Yu CHEN zheng-Ming XU ling liU li-li WANG Ying-Ming liU Department of Cardiology the Sixth Medical CenterChinese PLA General HospitalBeijingChina

In the aging populations of China,there is an increasing prevalence of various types of bradycardias that require pacing therapy.In 1958,the first transvenous pacemaker(TVPM)was implanted at Karolinska Hospital in Sweden,which unveiled the era of cardiac pacing therapy.[1]A TVPM includes transvenous electrodes and a pulse gener-ator that is implanted subcutaneously.Despite its obvious benefits,the complication rate associated with TVPM could be as high as 10%.

关键词： cardiac venous implantation

Current Status and Development Tendency of Wearable Cardiac Health Monitoring

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Chinese Journal of Electrical Engineering 2023年第1期9卷 71-92页

作者： Yifeng Wang zheng Zhao Jiangtao li School of Electrical Engineering Xi’an Jiaotong UniversityXi’an 710049China

Wearable cardiac monitoring devices can provide uninterrupted monitoring of cardiac activities over a long period of time.They have developed rapidly in recent years in terms of convenience,comfort,and intelligence.Aided by the development of sensor and materials technology,big data and artificial intelligence,wearable cardiac monitoring can become a crucial basis for novel medical models in the future.Herein,the basic concepts and representative devices of wearable cardiac monitoring are first introduced.Subsequently,its core technologies and the latest representative research progress in physiology signal sensing,signal quality enhancement,and signal reliability are systematically reviewed.Finally,an insight and outlook on the future development trends and challenges of wearable cardiac monitoring are discussed.

关键词： Wearable cardiac monitoring electrocardiogram seismocardiography photoplethysmogram cardiovascular disease

Local L^(2) theory of the fractional Navier-Stokes equations and the self-similar solution

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Science China Mathematics 2023年第3期66卷 503-570页

作者： Baishun Lai Jingyue li Xiaoxin zheng Key Laboratory of Computing and Stochastic Mathematics(Ministry of Education) School of Mathematics and StatisticsHunan Normal UniversityChangsha 410081China Institute of Applied Physics and Computational Mathematics Beijing 100088China School of Mathematical Sciences Beihang UniversityBeijing 100191China

This paper is concerned with two aspects of the fractional Navier-Stokes equation. First, we establish the local L^(2)theory of the hypo-dissipative Navier-Stokes system. More precisely, the existence of local-in-time as well as global-in-time local energy weak solutions to the hypo-dissipative Navier-Stokes system is proved.In particular, in order to construct a pressure with an explicit representation, some technical innovations are required due to the lack of known results on the local regularity of the non-local Stokes operator. Secondly, as an important application to the local L^(2)theory, we give a second construction of large self-similar solutions of the hypo-dissipative Navier-Stokes system along with the Leray-Schauder degree theory.

关键词： local energy weak solution self-similar solution Leray-Schauder degree theory

Okazaki fragment maturation:nucleases take centre stage

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分子细胞生物学报:英文版 2011年第1期3卷 23-30页

作者： Li Zheng Binghui Shen Department of Cancer Biology City of Hope National Medical Center and Beckman Research InstituteDuarteCA 91010USA

Completion of lagging strand DNA synthesis requires processing of up to 50 million Okazaki fragments per cell cycle in mammalian cells.Even in yeast,the Okazaki fragment maturation happens approximately a million times during a single round of DNA replication.Therefore,efficient processing of Okazaki fragments is vital for DNA replication and cell proliferation.During this process,primase-synthesized RNA/DNA primers are removed,and Okazaki fragments are joined into an intact lagging strand DNA.The processing of RNA/DNA primers requires a group of structure-specific nucleases typified by flap endonuclease 1(FEN1).Here,we sum-marize the distinct roles of these nucleases in different pathways for removal of RNA/DNA primers.Recent findings reveal that Okazaki fragment maturation is highly coordinated.The dynamic interactions of polymerase d,FEN1 and DNA ligase I with prolif-erating cell nuclear antigen allow these enzymes to act sequentially during Okazaki fragment maturation.Such protein–protein interactions may be regulated by post-translational modifications.We also discuss studies using mutant mouse models that suggest two distinct cancer etiological mechanisms arising from defects in different steps of Okazaki fragment maturation.Mutations that affect the efficiency of RNA primer removal may result in accumulation of unligated nicks and DNA double-strand breaks.These DNA strand breaks can cause varying forms of chromosome aberrations,contributing to development of cancer that associates with aneuploidy and gross chromosomal rearrangement.On the other hand,mutations that impair editing out of polymerase a incorporation errors result in cancer displaying a strong mutator phenotype.

关键词： Okazaki fragment maturation FEN1 DNA2 PCNA RPA cancer

Emerging low-nuclearity supported metal catalysts with atomic level precision for efficient heterogeneous catalysis

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Nano Research 2022年第9期15卷 7806-7839页

作者： Xiaobo zheng Beibei li Qishun Wang Dingsheng Wang Yadong li Department of Chemistry Tsinghua UniversityBeijing 100084China

Supported atomically dispersed metal catalysts(ADMCs)have received enormous attention due to their high atom utilization efficiency,mass activity and excellent selectivity.Single-atom site catalysts(SACs)with monometal-center as the quintessential ADMCs have been extensively studied in the catalysis-related fields.Beyond SACs,novel atomically dispersed metal catalysts(NADMCs)with flexible active sites featuring two or more catalytically centers including dual-atom and triple-atom catalysts have drawn ever-increasing attention recently.Owing to the presence of multiple neighboring active sites,NADMCs could exhibit much higher activity and selectivity compared with SACs,especially in those complicated reactions with multi-step intermediates.This review comprehensively outlines the recent exciting advances on the NADMCs with emphasis on the deeper understanding of the synergistic interactions among multiple metal atoms and underlying structure-performance relationships.It starts with the systematical introduction of principal synthetic approaches for NADMCs highlighting the key issues of each fabrication method including the atomically precise control in the design of metal nuclearity,and then the state-of-the-art characterizations for identifying and monitoring the atomic structure of NADMCs are explored.Thereafter,the recent development of NADMCs in energy-related applications is systematically discussed.Finally,we provide some new insights into the remaining challenges and opportunities for the development of NADMCs.

关键词： dual-atom catalysts atomically precise control synthesis strategy synergistic interactions structure-performance relationships

EPR study of charge separation associated states and reversibility of surface bound superoxide radicals in SrTiO_(3) photocatalyst

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Journal of Energy Chemistry 2022年第7期31卷 388-393,I0011页

作者： Xianwen Zhang zheng li Bin Zeng Can li Hongxian Han State Key Laboratory of Catalysis and Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China

Understanding the processes of charge generation, transfer and capture is important for the design and synthesis of efficient photocatalysts. In this work, light-induced charge separation and effect of O_(2) on electron transfer processes in SrTiO_(3) were investigated by electron paramagnetic resonance(EPR). It was found that photoinduced electron transfer from O_(2)- to Ti^(4+) produced Ti^(3+) and O- redox radical pairs under vacuum condition. Under oxygen atmosphere, however, surface bound superoxide radicals O_(2)-were formed by electron reduction of adsorbed oxygen at initial photoirradiation stage, and quenched by the reverse electron transfer to Ti^(4+) upon further photoirradiation. Formation of long-lived charge separation associated [Ti^(3+)---O-] species and the reversibility of surface bound superoxide radicals mediating the processes of photogenerated electrons may be accountable for the high activity of SrTiO_(3) in photocatalytic water splitting reaction.

关键词： Photocatalyst Electron paramagnetic resonance Charge separation Superoxide radicals

Spectrum and Spectral Singularities of a Quadratic Pencil of a Schr?dinger Operator with Boundary Conditions Dependent on the Eigenparameter

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Acta Mathematica Sinica,English Series 2023年第11期39卷 2164-2180页

作者： Xiang ZHU Zhao Wen zheng Kun li School of Mathematical Sciences Qufu Normal UniversityQufu 273165P.R.China College of Mathematics and Systems Science Guangdong Polytechnic Normal UniversityGuangzhou 510665P.R.China

In this paper,we consider the following quadratic pencil of Schr?dinger operators L(λ)generated in L~2(R~+)by the equation−y″+[p(x)+2λq(x)]y=λ^(2)y,x∈R^(+)=[0,+∞)with the boundary condition y′(0)/y(0)=β_(1)λ+β0-α_(1)λ+α0,where p(x)and q(x)are complex valued functions andα_(0),α_(1),β_(0),β_(1)are complex numbers withα_(0)β_(1)-α_(1)β_(0)≠0.It is proved that L(λ)has a finite number of eigenvalues and spectral singularities,and each of them is of a finite multiplicity,if the conditions p(x),q′(x)∈AC(R^(+)),limx→∞[|p(x)|+|q(x)|+|q′(x)|]=0 and sup 0≤x0.

关键词： Schrodinger operator Strum-liouville problems finite spectrum eigenparameter dependence

Preoperative prognostic nutritional index predicts long-term outcomes of patients with ampullary adenocarcinoma after curative pancreatoduodenectomy

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WORLD JOURNAL OF GASTROINTESTINAL SURGERY 2024年第5期16卷 1291-1300页

作者： Sun, Chong-Yuan Zhang, Xiao-Jie li, zheng Fei, He li, Ze-Feng Zhao, Dong-Bing Chinese Acad Med Sci & Peking Union Med Coll Natl Canc Ctr Dept Pancreat & Gastr Surg Oncol Natl Clin Res Ctr CancCanc Hosp 17 PanjiayuanNanli Beijing 100021 Peoples R China

BACKGROUND The prognostic nutritional index (PNI), a marker of immune-nutrition balance, has predictive value for the survival and prognosis of patients with various cancers. AIM To explore the clinical significance of the preoperative PNI on the prognosis of ampullary adenocarcinoma (AC) patients who underwent curative pancreaticoduodenectomy. METHODS The data concerning 233 patients diagnosed with ACs were extracted and analyzed at our institution from January 1998 to December 2020. All patients were categorized into low and high PNI groups based on the cutoff value determined by receiver operating characteristic curve analysis. We compared disease-free survival (DFS) and overall survival (OS) between these groups and assessed prognostic factors through univariate and multivariate analyses. RESULTS The optimal cutoff value for the PNI was established at 45.3. Patients with a PNI >= 45.3 were categorized into the PNI-high group, while those with a PNI lirubin and a lower creatinine level than were those in the PNI-high group. The 5-year OS rates for patients with a PNI >= 45.3 and a PNI The PNI is a straightforward and valuable marker for predicting long-term survival after pancreatoduodenectomy. The PNI should be incorporated into the standard assessment of patients with AC.

关键词： Ampullary carcinoma Prognostic nutritional index Prognosis Pancreaticoduodenectomy POSTOPERATIVE COMPliCATIONS SERUM-ALBUMIN CANCER INFLAMMATION