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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

Structural and Expressional Variations of the Mitochondrial Genome Conferring the Wild Abortive Type of Cytoplasmic Male Sterility in Rice

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Journal of Integrative Plant Biology 2007年第6期49卷 908-914页

作者： Zhen-Lan Liu hong Xu Jing-xin guo Yao-Guang Liu Key Laboratory of Plant Functional Genomics and Biotechnology of Education Department Guangdong Province College of Life Sciences South China Agricultural University Guangzhou 510642 China

The so-called ＂wild abortive＂（WA） type of cytoplasmic male sterility （CMS） derived from a wild rice species Oryza rufipogon has been extensively used for hybrid rice breeding. However, extensive analysis of the structure of the related mitochondrial genome has not been reported, and the CMS-associated gene（s） remain unknown. In this study, we exploited a mitochondrial genome-wide strategy to examine the structural and expressional variations in the mitochondrial genome conferring the CMS. The entire mitochondriai genomes of a CMS-WA line and two normal fertile rice lines were amplified by Long-polymerase chain reaction into tilling fragments of up to 15.2 kb. Restriction and DNA blotting analyses of these fragments revealed that structural variations occurred in several regions in the WA mitochondrial genome, as compared to those of the fertile lines. All of the amplified fragments covering the entire mitochondrial genome were used as RNA blot probes to examine the mitochondriai expression profile among the CMS-WA and fertile lines. As a result, only two mRNAs were found to be differentially expressed between the CMS-WA and the fertile lines, which were detected by a probe containing the nad5 and orf153 genes and the other having the ribosomal protein gene rpl5, respectively. These mRNAs are proposed to be the candidates for further identification and functional studies of the CMS gene.

关键词： cytoplasmic male sterility mitochondrial genome rice transcription.

Conditions and Stimulation for Germination in Glycyrrhiza uralensis Fisch Seeds

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Agricultural Sciences in China 2008年第12期7卷 1438-1444页

作者： MAO Pei-sheng WANG Yu-hong WANG xin-guo LIAN Jia-jie HUANG Ying Forage Seed Lab China Agricultural University Beijing 100193 P.R.China

Evaluation of seed quality is the key to seed distributing and seeding of Glycyrrhiza uralensis Fisch, as an important species for pharmacy and soil conservation. Here, we study the effects of light and temperature on seed germination and mechanical and chemical scarification on breaking the seed coat. Seeds were collected in 2004, 2005, and 2006, placed in Petri dishes, and incubated at constant temperature 20, 25, and 30℃, and alternating temperature 15-25, 20-30, 15-30, and 20-35℃ under either an 8h photoperiod or total darkness for 28 consecutive days. Different methods were used to break the dormancy owing to hard seededness in this species such as chemical scarification by immersing in concentrated sulphuric acid for 5, 10, 15, 20, 25, 30, 45, and 60 min, in 0.2% KNO3 solution to saturate the seedbed, and prechilling for 7 d at 7℃ and mechanical scarification by cutting. The results showed that alternating temperature at 20-30℃ with 8 h photoperiod and 16 h darkness was optimum for G. uralensis seed germinating in the laboratory. Hard seeds were broken by concentrated sulphuric acid soaking or mechanical scarification by cutting. Germination of seeds harvested in two different years was both promoted by immersing for 30-45 min in concentrated sulphuric acid. KNO3 solution was ineffective for reducing hard seeds. During seed germinating, the first count was on the 7th day and the last count was on the 14th day.

关键词： seed germination seed hardness seed scarification Glycyrrhiza uralensis

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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多孔预制件内Al-Cu合金的离心渗流过程

上海交通大学学报 2009年第10期43卷 1616-1621页

作者：汪凯李艳红胡国新上海交通大学机械与动力工程学院上海200240

根据渗透过程的区域组成,分析并推导一维绝热渗流动力学方程.联立热、质传递方程,采用Boltzmann转换及参数迭代法简化模型求解.计算结果表明,增大预制件的预热温度、孔隙率,重熔区的长度增加,渗透前沿溶质铜浓度相应减小;进口合金过热... 详细信息

根据渗透过程的区域组成,分析并推导一维绝热渗流动力学方程.联立热、质传递方程,采用Boltzmann转换及参数迭代法简化模型求解.计算结果表明,增大预制件的预热温度、孔隙率,重熔区的长度增加,渗透前沿溶质铜浓度相应减小;进口合金过热程度加剧,重熔区长度增加明显;提高离心转速,重熔区长度减小,渗透前沿平均溶质浓度升高;转速过高渗透区域的压力显著增大,增加了对预制件的强度要求.应结合预制件的实际参数及试验来合理控制离心转速.

关键词：离心渗流 Al-Cu合金多孔预制件数值模拟