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On Gradient Solitons of the Ricci–Harmonic Flow

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Acta Mathematica Sinica,English Series 2015年第11期31卷 1798-1804页

作者： hong xin guo Robert PHILIPOWSKI Anton THALMAIER School of Mathematics and Information Science Wenzhou University Mathematics Research Unit University of Luxembourg

In this paper, we study gradient solitons to the Ricci flow coupled with harmonic map heat flow. We derive new identities on solitons similar to those on gradient solitons of the Ricci flow. When the soliton is compac... 详细信息

关键词： Ricci flow harmonic map heat flow gradient solitons quasi-Einstein manifold

A Note on Harnack Type Inequality for the Gaussian Curvature Flow

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Acta Mathematicae Applicatae Sinica 2022年第1期38卷 1-4页

作者： Cai-peng CHEN hong-xin guo Cheng-zhe ZHU Department of mathematics Wenzhou UniversityWenzhou 325035China

In this short note we present a new Harnack expression for the Gaussian curvature flow, which is modeled from the shrinking self similiar solutions. As applications we give alternate proofs of Chow’s Harnack inequali... 详细信息

关键词： Gaussian Curvature flow Harnack inequality

Dynamic changes in the expression of growth factor receptors in the myocardium microvascular endothelium after murine myocardial infarction

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Chinese Medical Journal 2007年第6期120卷 485-490页

作者： WANG xin-hong ZHANG guo-ping JIN Hui-ming CHEN Si-feng Department of Physiology and Pathophysiology Shanghai Medical College Fudan University Shanghai 200032 China

Background After myocardial infarction, specific growth factors promote cardiac angiogenisis, leading to a therapeutic effect. Although this effect is mediated by specific receptors in the endothelium of the cardiac microvasculature, few studies have investigated dynamic changes in their expression. We explored this phenomenon in a murine model. Methods We observed the mRNA expression of receptors by specific angiogenesis gene microarray at day 3 and day 7 after infarction. The vascular endothelial growth factor （VEGF） receptor FIk-1 was observed at the protein level at day 3 and day 7 by immunohistochemistry. The dynamic expression of fibroblast growth factor receptor-1 （FGFR-1） mRNA in the border zone and the noninfarcted zone at day 3, day 7, day 14, and day 42 was investigated by real-time PCR. Statistical significance was analyzed with SPSS 10o0 software using one-way analysis of variance （ANOVA）. Results Three days after infarction, 9 receptors in the border zone and 7 receptors in the noninfarcted zone were down-regulated. Two receptors in the infarct edge and 5 receptors in the distant myocardium were up-regulated. However at day 7, 11 receptors in the border zone were up-regulated, and only one was down-regulated. In the border zone, FIk-1 levels decreased at day 3 but increased significantly at day 7. Real-time PCR showed that FGFR-1 mRNA decreased markedly in the border zone at day 3 but increased afterward for at least 6 weeks. In the early stage （3 days） after infarction, the expression of receptors had decreased to some extent. However, at day 7, receptor expression was active and had moved from the distant noninfarcted zone to the border zone as a part of the acute repair process. Conclusion Selecting the proper growth factors to target receptors with protective activity, and determining appropriate therapeutic timing may be important to the success of therapeutic angiogenesis.

关键词： growth factor receptor gene microarray acute myocardial infarction

Medical comorbidities at admission is predictive for 30-day in-hospital mortality in patients with acute myocardial infarction： analysis of 5161 cases

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Journal of Geriatric Cardiology 2011年第1期8卷 31-34页

作者： Xue-Dong Yang Yu-Sheng Zhao Yu-Feng Li xin-hong guo Institute of Geriatric Cardiology Chinese PLA General Hospital Beijing 100853 China

Background The present study investigated the prognostic value of medical comorbidities at admission for 30-day in-hospital mortality in patients with acute myocardial infarction （AMI）. Methods A total of 5161 patients with AMI were admitted in Chinese PLA General Hospital between January 1, 1993 and December 31, 2007. Medical comorbidities including hypertension, diabetes mellitus, previous myocardial infarction, valvular heart disease, chronic obstructive pulmonary disease （COPD）, renal insufficiency, previous stroke, atrial fibrillation and anemia, were identified at admission. The patients were divided into 4 groups based on the number of medical comorbidities at admission （0, 1, 2, and ≥3）. Cox regression analysis was used to calculate relative risk （RR） and 95% confidence intervals （CI）, with adjustment for age, sex, heart failure and percutaneous coronary intervention （PCI）. Results The mean age of the studied population was 63.9 ± 13.6 years, and 80.1% of the patients were male. In 74.6% of the patients at least one comorbidity were identified. Hypertension （50.7%）, diabetes mellitus （24.0%） and previous myocardial infarction （12%） were the leading common comorbidities at admission. The 30-day in-hospital mortality in patients with 0, 1, 2, and ≥3 comorbidities at admission （7.2%） was 4.9%, 7.2%, 11.1%, and 20.3%, respectively. The presence of 2 or more comorbidities was associated with higher 30-day in-hospital mortality compared with patients without comorbidity （RR： 1.41, 95% CI： 1.13-1.77, P = 0.003, and RR： 1.95, 95% CI： 1.59-2.39, P = 0.000, respectively）. Conclusions Medical comorbidities were frequently found in patients with AMI. AMI patients with more comorbidities had a higher 30-day in-hospital mortality might be predictive of early poor outcome in patients with AMI.

关键词： acute myocardial infarction comorbidity mortality

Cardiovascular and cerebrovascular outcomes in elderly hypertensive patients treated with either ARB or ACEI

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Journal of Geriatric Cardiology 2012年第3期9卷 252-257页

作者： Cong Ma Jian Cao Xue-Chun Lu xin-hong guo Yan Gao Xian-Feng Liu Li Fan The First Department of Geriatric Cardiology South Building Chinese PLA General Hospital 28 Fuxing Road Beij'ing 100853 China Geriatric Department of Hematology South Building Chinese PLA General Hospital 28 Fuxing Road Beij'ing 100853 China The Institute of Geriatric Cardiology Chinese PLA General Hospital 28 Fuxing Road Beo'ing 100853 China

Background Although angiotensin converting enzyme inhibitors （ACEI） and angiotensin receptor blockers （ARB） are equally important in the treatment of hypertension, there is less evidence whether they have equal cardiovascular and cerebrovascular protective effects, especially in elder hypertensive patients. This study aims to clarify this unresolved issue. Methods This cross-sectional study included clinical data on 933 aged male patients with hypertension who received either an ARB or ACEI for more than two months between January 2007 and May 2011. The primary outcome was the composite of cardiovascular death, non-fatal myocardial infarction, and non-fatal stroke. The secondary endpoints were unstable angina, new atrial fibrillation, and transient ischemic attack. Results The median follow-up time was 24 months. Age, drug types, cerebral infarction history, renal dysfunction history were the independent predictors of the primary endpoint. The risk of an occurrence of a primary endpoint event was higher in the ARB group than the ACEI group [P = 0.037, hazard ratios （HR）： 2.124, 95% confidence interval （95% CI）： 1.048-4.306]. The Kaplan-Meier method also suggests that the rate of primary endpoint occurrence was higher in the ARB group than the ACEI group （P = 0.04）. In regard to the secondary endpoints, there were no significant differences between the two treatment arms （P = 0.137, HR： 1.454, 95% CI： 0.888-2.380）. Patient age and coronary heart disease history were independent predictors of the secondary endpoint. Conclusion ACEI were more effective than ARB in reducing cardiovascular and cerebrovascular morbidity and mortality in aged patients with hypertension.

关键词： Angiotensin receptor blocker Angiotensin converting enzyme inhibitor Renin-angiotensin-aldosterone system Angiotensintype 2 receptor

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曲线流在平面曲线的几个不等式中的应用

数学学报（中文版） 2023年第4期66卷 687-692页

作者：夏康杰郭洪欣温州大学数理学院数学系温州325035

通过建立平面中的曲线收缩流的单调公式,给出三个几何不等式新的证明.特别地,通过经典曲线收缩流给出了R^(2)上Ros定理一个新的证明,通过一种保面积的曲线收缩流分别给出了R^(2)上Ros定理以及其加强形式和曲线的熵不等式新的证明.

关键词：曲线收缩流 R^(2)上的Ros定理曲线的熵不等式

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大豆播种机双V型筑沟器设计与试验

吉林大学学报（工学版） 2017年第1期47卷 323-331页

作者：贾洪雷郑嘉鑫袁洪方郭明卓王文君于路路吉林大学生物与农业工程学院长春130022 吉林大学工程仿生教育部重点实验室长春130022

为了提高种沟质量、播种深度一致性,保证大豆垄上双行精密播种作业效果,设计了一种双V型筑沟器,可单独使用进行开沟作业,亦可与圆盘开沟器配合作业。在开沟深度分别为40、50、60mm,行走速度分别为1.9、2.2、2.5m/s作业工况下,以播种后... 详细信息

为了提高种沟质量、播种深度一致性,保证大豆垄上双行精密播种作业效果,设计了一种双V型筑沟器,可单独使用进行开沟作业,亦可与圆盘开沟器配合作业。在开沟深度分别为40、50、60mm,行走速度分别为1.9、2.2、2.5m/s作业工况下,以播种后的播深变异系数和播种横向变异系数为评价指标,对设计的双V型筑沟器与圆盘开沟器进行大豆田间对比试验。试验结果表明:相对于圆盘开沟器,双V型筑沟器开沟深度均匀,开出种沟较窄,沟形稳定,有利于保证播种深度一致性、种子分布直线性,提高播种质量。单独使用双V型筑沟器,在开沟速度为1.9m/s、开沟深度为40mm时,播深变异系数最小(0.086);在开沟速度为1.9m/s、开沟深度为60mm时,播种横向变异最小(1.356)。采用Design-Expert软件对试验数据优化分析得到,圆盘开沟器与双V型筑沟器组合作业效果优于单独使用双V型筑沟器,开沟深度57mm、行走速度1.9m/s为最优作业工况,此时播深变异系数为0.15,播种横向变异系数为1.25,重复性田间试验证明了模型的最优作业工况。

关键词：农业工程双V型筑沟器开沟器播深变异系数播种横向变异系数

Constructing Donor–Acceptor‑Linked COFs Electrolytes to Regulate Electron Density and Accelerate the Li^(+)Migration in Quasi‑Solid‑State Battery

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Nano-Micro Letters 2025年第1期17卷 456-471页

作者： Genfu Zhao Hang Ma Conghui Zhang Yongxin Yang Shuyuan Yu Haiye Zhu Yongjiang Sun hong guo School of Materials and Energy International Joint Research Center for Advanced Energy Materials of Yunnan ProvinceYunnan UniversityKunming 650091People’s Republic of China Yunnan Yuntianhua Co. LtdR&D CenterKunming 650228People’s Republic of China Southwest United Graduate School Kunming 650091People’s Republic of China

Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective Li^(+)transportation and conduction in solid-state Li metal *** study reports a high-performance solid-state electrolyte thorough D–A-linked covalent organic frameworks(COFs)based on intramolecular charge transfer *** other reported COFbased solid-state electrolyte,the developed concept with D–A-linked COFs not only achieves electronic modulation to promote highly-selective Li^(+)migration and inhibit Li dendrite,but also offers a crucial opportunity to understand the role of electronic density in solid-state Li metal *** introduced strong electronegativity F-based ligand in COF electrolyte results in highlyselective Li^(+)(transference number 0.83),high ionic conductivity(6.7×10^(-4)S cm^(−1)),excellent cyclic ability(1000 h)in Li metal symmetric cell and high-capacity retention in Li/LiFePO_(4)cell(90.8%for 300 cycles at 5C)than substituted C-and N-based *** is ascribed to outstanding D–A interaction between donor porphyrin and acceptor F atoms,which effectively expedites electron transferring from porphyrin to F-based ligand and enhances Li^(+)***,we anticipate that this work creates insight into the strategy for accelerating Li^(+)conduction in high-performance solid-state Li metal batteries through D–A system.

关键词： Electronic modulation engineering Donor-acceptor-linked covalent organic frameworks Quasi-solid-state Li metal battery

Advances in Graphene‑Based Electrode for Triboelectric Nanogenerator

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Nano-Micro Letters 2025年第1期17卷 378-403页

作者： Bin Xie Yuanhui guo Yun Chen Hao Zhang Jiawei Xiao Maoxiang Hou Huilong Liu Li Ma xin Chen Chingping Wong State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006People’s Republic of China School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006People’s Republic of China School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

With the continuous development of wearable electronics,wireless sensor networks and other micro-electronic devices,there is an increasingly urgent need for miniature,flexible and efficient nanopower generation *** nanogenerator(TENG)technology can convert small mechanical energy into electricity,which is expected to address this *** the core component of TENG,the choice of electrode materials significantly affects its *** metal electrode materials often suffer from problems such as durability,which limits the further application of ***,as a novel electrode material,shows excellent prospects for application in TENG owing to its unique structure and excellent electrical *** review systematically summarizes the recent research progress and application prospects of TENGs based on graphene *** precision processing methods of graphene electrodes are introduced,and the applications of graphene electrode-based TENGs in various scenarios as well as the enhancement of graphene electrodes for TENG performance are *** addition,the future development of graphene electrode-based TENGs is also prospectively discussed,aiming to promote the continuous advancement of graphene electrode-based TENGs.

关键词： Triboelectric nanogenerator Precision processing Graphene electrode Self-powered sensor