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A Remark on Steinness

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Chinese Annals of Mathematics,Series B 2007年第2期28卷 161-164页

作者： Chaohui zhou Zhihua chen Department of Applied Mathematics Tongji University Shanghai 200092 China.

In this paper, the authors prove that if Mn is a complete noncompact Kaehler manifold with a pole p, and its holomorphic bisectional curvature is asymptotically nonnegative to p, then it is a Stein manifold.

关键词： Holomorphic bisectional curvature Plurisubharmonic Smooth Exhausting

A parameterization scheme for upward lightning in the cloud model and a discussion of the initial favorable environmental characteristics in the cloud

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Science China Earth Sciences 2016年第7期59卷 1440-1453页

作者： TAN Yong Bo chen Chao zhou Jie chen zhou Bo Wen ZHANG DongDong GUO XiuFeng Key Laboratory of Meteorological Disaster Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science & Technology

The upward lightning(UL) initiated from the top of tall buildings(at least above 100 m) is a type of atmospheric discharge. Currently, we understand the nature of the UL from ground observations, but the corresponding theoretical research is lacking. Based on an existing bidirectional leader stochastic model, a stochastic parameterization scheme for the UL has been built and embedded in an existing two-dimensional thundercloud charge/discharge model. The ULs simulated from the experiments with two-dimensional high resolution agree generally with the observation results. By analyzing the charge structure of thunderstorm clouds, we determined the in-cloud environmental characteristics that favor the initiation of conventional cloud-to-ground(CG) flashes and analyzed the differences and similarities of some characteristics of the positive and the negative UL. Simulation results indicate that the positive ULs are typically other-lightning-triggered ULs(OLTUL) and are usually a discharge phenomenon between the ground and the lower positive charge region appearing below the main middle negative charge region. The effect of the previous in-cloud lightning(IC) process of space electrical field provides favorable conditions for the initiation of a positive UL. Its entire discharge process is limited, and the branches of the leader are fewer in number as its discharge is not sufficient. A negative UL is generally a discharge phenomenon of the dipole charge structure between the ground and the main negative charge region. The lower temperature stratification and the sinking of the hydrometeors typically initiate a negative UL. Negative ULs develop strongly and have more branches. The OLTUL is initiated mainly during the development stage of a thunderstorm, while the self-triggered UL(STUL) is initiated mainly during the dissipation stage of a thunderstorm.

关键词： Upward lightning Numerical simulation Initial conditions Propagation characteristics Thunderstorm cloud model

Case Report:Recurrent severe vomiting due to hyperthyroidism

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第3期11卷 218-220页

作者： Li-ying chen Bo zhou zhou-wen chen Li-zheng FANG Department of Family Medicine Sir Run Run Shaw Hospital School of Medicine Zhejiang University Hangzhou 310016 China Department of Family Medicine Community Health Services Center in Pengbu Town Hangzhou 310017 China

Thyrotoxicosis may present in many ways;severe vomiting as a prominent symptom of thyrotoxicosis is *** this paper,we report a 24-year-old Chinese male with hyperthyroidism who presented with recurrent severe *** patient had had intermittent vomiting for seven years and had lost approximately 15 kg of *** examinations revealed chronic gastritis and one occasion peptic *** was treated with antacid and proton pump inhibitors,but his symptoms had no *** presenting symptoms suggested hyperthyroidism and were confirmed by laboratory *** a month of propylthiouracil therapy,his symptoms were *** should be noted that hyperthyroidism patients can have unexplained vomiting,and that hyperthyroidism may coexist with peptic ulcer in rare *** of such atypical presentations of hyperthyroidism may help to make a correct diagnosis.

关键词： Vomiting Hyperthyroidism Peptic ulcer

Calculating the Climatology and Anomalies of Surface Cloud Radiative Effect Using Cloud Property Histograms and Cloud Radiative Kernels

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Advances in Atmospheric Sciences 2022年第12期39卷 2124-2136页

作者： chen zhou Yincheng LIU Quan WANG School of Atmospheric Sciences Nanjing UniversityNanjing 210093China

Cloud radiative kernels(CRK)built with radiative transfer models have been widely used to analyze the cloud radiative effect on top of atmosphere(TOA)fluxes,and it is expected that the CRKs would also be useful in the analyses of surface radiative fluxes,which determines the regional surface temperature change and *** this study,CRKs at the surface and TOA were built using the Rapid Radiative Transfer Model(RRTM).Longwave cloud radiative effect(CRE)at the surface is primarily driven by cloud base properties,while TOA CRE is primarily decided by cloud top *** this reason,the standard version of surface CRK is a function of latitude,longitude,month,cloud optical thickness(τ)and cloud base pressure(CBP),and the TOA CRK is a function of latitude,longitude,month,τand cloud top pressure(CTP).Considering that the cloud property histograms provided by climate models are functions of CTP instead of CBP at present,the surface CRKs on CBP-τhistograms were converted to CTP-τfields using the statistical relationship between CTP,CBP andτobtained from collocated CloudSat and MODIS *** both climate model outputs and satellites observations,the climatology of surface CRE and cloud-induced surface radiative anomalies calculated with the surface CRKs and cloud property histograms are well correlated with those calculated from surface radiative *** cloud-induced surface radiative anomalies reproduced by surface CRKs and MODIS cloud property histograms are not affected by spurious trends that appear in Clouds and the Earth's Radiant Energy System(CERES)surface irradiances products.

关键词： cloud radiative kernel surface radiative flux cloud feedback cloud properties cloud top pressure cloud base pressure

Electron acceleration by Langmuir turbulence in ionospheric heating

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Earth and Planetary Physics 2022年第6期6卷 529-535页

作者： MoRan Liu chen zhou Ting Feng Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

In this study,we investigate the generation of parametric decay instability,Langmuir turbulence formation,and electron acceleration in ionospheric heating via a two-fluid model using the Fokker-Planck equation and Vlasov-Poisson system *** simulation results of both the magnetofluid model and the kinetic model demonstrate the dynamics of electron ***,the results of the Vlasov-Poisson simulations suggest the formation of electron holes in phase space at the same spatial scale as the Langmuir wave,which are shown to be related to electron *** addition,electron acceleration is enhanced through the extension of the wavenumber spectrum caused by strong Langmuir turbulence,leading to more electron holes in phase space.

关键词： electron acceleration Langmuir turbulence electron holes parametric decay instability

Widening and weakening of the Hadley circulation under global warming

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Science Bulletin 2018年第10期63卷 640-644页

作者： Yongyun Hu Han Huang chen zhou Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking University School of Atmospheric Sciences Nanjing University

The Hadley circulation is one of the most important atmospheric *** of the Hadley circulation has drawn extensive studies in the past *** key concern is that widening of the Hadley circulation would cause poleward shift of the subtropical dry *** metrics have been applied to measure the widening of the *** are responsible for the observed widening trends of the Hadley circulation? How anthropogenic and natural forcings caused the widening? How the widening results in regional climatic effects? These are the major questions in studing the widening of the Hadley *** both observations and simulations all show widening of the Hadley circulation in the past few decades,there are no general agreements of changes in the strength of the Hadley *** some reanalysis datasets show strengthening of the Hadley circulation,it was shown that the strengthening trend could be artificial,and simulations show weakening of the Hadley circulation for global greenhouse *** the present paper,we shall briefly review the major progresses of studies in trends in width and strength of the Hadley *** address answers to these questions,clarify inconsistent results,and propose ideas for future studies.

关键词： Hadley circulation Greenhouse gases Ozone depletion ENSO Global warming

RECONSTRUCTION STABILITY OF NEARFIELD ACOUSTIC HOLOGRAPHY

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Chinese Journal of Mechanical Engineering 2005年第4期18卷 504-509页

作者： Bi Chuanxing chen Xinzhao zhou Rong chen Jian Institute of Sound and Vibration Research Hefei University of Technology Hefei 230009 China

The distributed source boundary point method （DSBPM） is used as the spatial transform algorithm for realizing nearfield acoustic holography （NAH）, the sensitivity of the reconstructed solution to the measurement errors is analyzed, and the regularization method is proposed to stabilize the reconstruction process, control the influence of the measurement errors and get a better approximate solution. An oscillating sphere is investigated as a numerical example, the influence of the measurement errors on the reconstruction solution is demonstrated, and the feasibility and validity of the regularization method are validated. Key words： Acoustic holography Boundary point method Inverse problem Regularization

关键词： Acoustic holography Boundary point method Inverse problem Regularization

Vibration suppression of composite panel with variable angle tow design and inerter-based nonlinear energy sink

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第8期24卷 653-672页

作者： chen zhou Jian YANG Yingdan ZHU chendi ZHU Zhejiang Provincial Key Laboratory of Robotics and Intelligent Manufacturing Equipment Technology Ningbo Institute of Material Technology&EngineeringChinese Academy of SciencesNingbo 315201China Department of Mechanical Materials and Manufacturing EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100China International Academy of Marine Economy and Technology(IAMET) University of Nottingham Ningbo ChinaNingbo 315100China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Ningbo Institute of Dalian University of Technology Ningbo 315016China

This study investigates the vibration transmission and suppression of a laminated composite panel with variable angle tow(VAT)designs and an attached inerter-based passive nonlinear energy *** on analytical and numerical methodologies,the substructure technique is used to obtain a steady-state dynamic response and the results are verified by experimental and analytical *** is demonstrated that fiber orientation has a significant impact on the natural *** dynamic responses and energy transmission path characteristics are determined and evaluated by forced vibration *** main vibration transmission paths inside the structure are displayed using power flow density *** is demonstrated that the dynamic responses of the plate can be changed considerably by using various fiber placement schemes and passive suppression *** addition,it is indicated that the vibration transmission paths are significantly influenced by the tailored fiber angles for improved dynamic *** investigation enhances the understanding of enhanced vibration suppression designs of variable-stiffness composite plates with attached passive devices.

关键词： Laminated composite plate Variable stiffness Substructure method Passive device Power flow analysis

Hypoxic microenvironment in cancer:molecular mechanisms and therapeutic interventions

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Signal Transduction and Targeted Therapy 2023年第3期8卷 1047-1069页

作者： zhou chen Fangfang Han Yan Du Huaqing Shi Wence zhou The First Clinical Medical College Lanzhou UniversityLanzhouGansuChina The First Hospital of Lanzhou University LanzhouGansuChina The Second Clinical Medical College Lanzhou UniversityLanzhouGansuChina Lanzhou University Sencond Hospital LanzhouGansuChina

Having a hypoxic microenvironment is a common and salient feature of most solid *** has a profound effect on the biological behavior and malignant phenotype of cancer cells,mediates the effects of cancer chemotherapy,radiotherapy,and immunotherapy through complex mechanisms,and is closely associated with poor prognosis in various cancer *** studies have demonstrated that through normalization of the tumor vasculature,nanoparticle carriers and biocarriers can effectively increase the oxygen concentration in the tumor microenvironment,improve drug delivery and the efficacy of *** also increase infiltration of innate and adaptive anti-tumor immune cells to enhance the efficacy of ***,drugs targeting key genes associated with hypoxia,including hypoxia tracers,hypoxia-activated prodrugs,and drugs targeting hypoxia-inducible factors and downstream targets,can be used for visualization and quantitative analysis of tumor hypoxia and antitumor ***,the relationship between hypoxia and cancer is an area of research that requires further ***,we investigated the potential factors in the development of hypoxia in cancer,changes in signaling pathways that occur in cancer cells to adapt to hypoxic environments,the mechanisms of hypoxia-induced cancer immune tolerance,chemotherapeutic tolerance,and enhanced radiation tolerance,as well as the insights and applications of hypoxia in cancer therapy.

关键词： drugs therapeutic microenvironment