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Analysis of phase preservation and interferometric offset test in sparse SAR imaging

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Science China(Information Sciences) 2024年第2期67卷 219-231页

作者： Zhongqiu xu Bingchen ZHANG Guangzuo LI xueli ZHAN Yanfei BAO Yirong WU Key Laboratory of Spatial Information Processing and Application System Technology Chinese Academy of Sciences Aerospace Information Research Institute Chinese Academy of Sciences School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of Sciences PLA Academy of Military Sciences

Sparse synthetic aperture radar(SAR) imaging has emerged as a reliable microwave imaging scheme in the recent decade and excels in down-sampling reconstruction and full-sampling performance improvements such as noise, sidelobe, speckle, and ambiguity suppression. To utilize complex image products of sparse reconstruction for improvement in polarimetric, interferometric, and tomographic SAR imaging, it is necessary to evaluate the phase preservation of sparse SAR imaging. In this study, we first introduce the general alternating direction method of multipliers(ADMM) as the universal framework for sparse reconstruction algorithms and adopt chirp scaling algorithm(CSA)-based azimuth-range decouple operators to avoid expensive data storage and processing. Further, we theoretically analyze the phase preservation of the sparse reconstruction algorithm through a comparison with the reconstruction results of CSA. Finally,we conduct the interferometric offset test on the sparse reconstruction results of simulated and real Gaofen-3(GF-3) SAR data, demonstrating the phase-preserving ability of sparse methods.

关键词： sparse SAR imaging phase preservation interferometric offset test general ADMM azimuth-range decouple

The storage and utilization of carbohydrates in response to elevation mediated by tree organs in subtropical evergreen broad-leaved forests

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Forest Ecosystems 2024年第1期11卷 52-61页

作者： Bin xu xueli Jiang Yingying Zong G.Geoff Wang Fusheng Chen Zhenyu Zhao Xiangmin Fang Key Laboratory of National Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed College of ForestryJiangxi Agricultural UniversityNanchang330045China Jiulianshan National Observation and Research Station of Chinese Forest Ecosystem College of ForestryJiangxi Agricultural UniversityNanchang330045China Department of Forestry and Environmental Conservation Clemson UniversityClemsonSC29634USA

Global climate change can affect tree growth and carbon sink function by influencing plant carbohydrate synthesis and utilization,while elevation can be used as an ideal setting under natural conditions to simulate climate change effects.The effect of elevation on tree growth may depend on organ type.However,the allocation patterns of nonstructural and structural carbohydrates(NSCs and SCs,respectively)in different tree organs and their response to elevation remain unclear.We selected four dominant tree species,Schima superba,Castanopsis eyrei,Castanopsis fargesii and Michelia maudiae,along an elevation gradient from 609 to 1,207 m in subtropical evergreen broad-leaved forests and analyzed leaf,trunk,and fine root NSCs,carbon(C),nitrogen(N)and phosphorus(P)concentrations and the relative abundance of SCs.Leaf NSCs increased initially and then decreased,and trunk NSCs increased with increasing elevation.However,root NSCs decreased with increasing elevation.The relative abundance of SCs in leaves and trunks decreased,while the relative abundance of root SCs increased with increasing elevation.No significant correlations between SCs and NSCs in leaves were detected,while there were negative correlations between SCs and NSCs in trunks,roots,and all organs.Hierarchical partitioning analysis indicated that plant C/N and C/P were the main predictors of changes in SCs and NSCs.Our results suggest that tree organs have divergent responses to elevation and that increasing elevation will inhibit the aboveground part growth and enhance the root growth of trees.A tradeoff between the C distribution used for growth and storage was confirmed along the elevation gradient,which is mainly manifested in the"sink"organs of NSCs.Our results provide insight into tree growth in the context of global climate change scenarios in subtropical forest ecosystems.

关键词： Nonstructural carbohydrates Structural carbohydrates Elevation Subtropical evergreen broad-leaved forests Tree organs

Gehua Jiejiu Dizhi decoction(葛花解酒涤脂汤)ameliorates alcoholic fatty liver in mice by regulating lipid and bile acid metabolism and with exertion of antioxidant stress based on 4DLabel-free quantitative proteomic study

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Journal of Traditional Chinese Medicine 2024年第2期44卷 277-288页

作者： HAN Min YI xu YOU Shaowei WU xueli WANG Shuoshi HE Diancheng Guizhou University of Traditional Chinese Medicine Graduate SchoolGuiyang 550025China Department of Clinical medical laboratory Department of Gastroenterologythe Second Affiliated Hospital of Guizhou University of Traditional Chinese MedicineGuiyang 550003China

OBJECTIVE:To analyze the effect and molecular mechanism of Gehua Jiejiu Dizhi decoction(葛花解酒涤脂汤,GJDD)on alcoholic fatty live disease(AFLD)by using proteomic methods.METHODS:The male C57BL/6J mouse were randomly divided into four groups:control group,model group,GJDD group and resveratrol group.After the AFLD model was successfully prepared by intragastric administration of alcohol once on the basis of the Lieber-DeCarli classical method,the GJDD group and resveratrol group were intragastrically administered with GJDD(4900 mg/kg)and resveratrol(400 mg/kg)respectively,once a day for 9 d.The fat deposition of liver tissue was observed and evaluated by oil red O(ORO)staining.4DLabel-free quantitative proteome method was used to determine and quantify the protein expression in liver tissue of each experimental group.The differentially expressed proteins were screened according to protein expression differential multiples,and then analyzed by Gene ontology classification and Kyoto Encyclopedia of Genes and Genomes pathway enrichment.Finally,expression validation of the differentially co-expressed proteins from control group,model group and GJDD group were verified by targeted proteomics quantification techniques.RESULTS:In semiquantitative analyses of ORO,all kinds of steatosis(ToS,MaS,and MiS)were evaluated higher in AFLD mice compared to those in GJDD or resveratroltreated mice.4DLabel-free proteomics analysis results showed that a total of 4513 proteins were identified,of which 3763 proteins were quantified and 946 differentially expressed proteins were screened.Compared with the control group,145 proteins were up-regulated and 148 proteins were down-regulated in the liver tissue of model group.In addition,compared with the model group,92 proteins were up-regulated and 135 proteins were downregulated in the liver tissue of the GJDD group.15 differentially co-expressed proteins were found between every two groups(model group vs control group,GJDD group vs model group and GJDD group vs control group),which were involv

关键词： fatty liver alcoholic 4DLabel-free quantitative proteome targeted protein quantification Gehua Jiejiu Dizhi decoction

Application of Sturm Theorem in the Global Controllability of a Class of High Dimensional Polynomial Systems

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Journal of Systems Science & Complexity 2015年第5期28卷 1049-1057页

作者： xu xueli LI Qianqian SUN Yimin Guangdong Province Key Laboratory of Computational Science School of Mathematics and Computational Science Sun Yat-Sen University

In this paper, the global controllability for a class of high dimensional polynomial systems has been investigated and a constructive algebraic criterion algorithm for their global controllability has been obtained. By the criterion algorithm, the global controllability can be determined in finite steps of arithmetic operations. The algorithm is imposed on the coefficients of the polynomials only and the analysis technique is based on Sturm Theorem in real algebraic geometry and its modern progress.Finally, the authors will give some examples to show the application of our results.

关键词： Global controllability high dimensional systems number of sign variations polynomial Sturm theorem.

新型冠状病毒感染合并高血糖症患者的研究现状及对高血糖管理策略的探讨

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四川大学学报（医学版） 2024年第1期55卷 230-235页

作者：夏娟杜丽娟席学莉徐筑萍贵州医科大学附属医院呼吸与危重症医学科贵阳550004 四川大学华西医院眼科成都610041

新型冠状病毒感染(coronavirus disease 2019,COVID-19)在全球范围内的大流行严重威胁着人类健康,特别是重型、危重型患者具有较高的死亡率,高血糖症是这类患者不良预后的高危因素。COVID-19患者容易出现高血糖症,无论既往是否患糖尿病... 详细信息

新型冠状病毒感染(coronavirus disease 2019,COVID-19)在全球范围内的大流行严重威胁着人类健康,特别是重型、危重型患者具有较高的死亡率,高血糖症是这类患者不良预后的高危因素。COVID-19患者容易出现高血糖症,无论既往是否患糖尿病。糖皮质激素治疗是COVID-19患者抗炎方案的重要治疗措施,而糖皮质激素的使用显著增加了COVID-19患者高血糖事件的发生,导致不良预后。及时的血糖监测及早期高血糖的干预将有利于COVID-19患者的病情转归。本文就近年来COVID-19患者并发高血糖症的潜在形成机制,以及针对该类患者血糖管理策略的研究进展作全面的综述,以期优化管理COVID-19患者的高血糖状态,改善疾病的转归。

关键词：新型冠状病毒感染糖皮质激素高血糖症血糖控制综述

Application of Sturm Theorem in the Global Controllability of a Class of High Dimensional Polynomial Systems

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Journal of Systems Engineering and Electronics 2015年第5期26卷 1049-1057页

作者： xu xueli LI Qianqian SUN Yimin Guangdong Province Key Laboratory of Computational Science School of Mathematics and Computational Science Sun Yat-Sen University

In this paper, the global controllability for a class of high dimensional polynomial systems has been investigated and a constructive algebraic criterion algorithm for their global controllability has been obtained. By the criterion algorithm, the global controllability can be determined in finite steps of arithmetic operations. The algorithm is imposed on the coefficients of the polynomials only and the analysis technique is based on Sturm Theorem in real algebraic geometry and its modern progress. Finally, the authors will give some examples to show the application of our results.

关键词： Global controllability high dimensional systems number of sign variations polynomial,Sturm theorem.

铝合金旋转激光焊接小孔与熔池耦合动态行为数值分析

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热加工工艺 2024年第7期53卷 23-27页

作者：王学礼张坦胥国祥龚祺龙江苏科技大学材料科学与工程学院江苏镇江212003

旋转激光对熔池的搅拌作用可以有效增加激光热源的作用范围,抑制激光焊接过程中的气孔等常见缺陷,提高焊接接头质量。由于旋转激光热源的物理特性,小孔和熔池的动态行为比传统的激光焊接更复杂。采用数值模拟的方法,在同时考虑小孔、反... 详细信息

旋转激光对熔池的搅拌作用可以有效增加激光热源的作用范围,抑制激光焊接过程中的气孔等常见缺陷,提高焊接接头质量。由于旋转激光热源的物理特性,小孔和熔池的动态行为比传统的激光焊接更复杂。采用数值模拟的方法,在同时考虑小孔、反冲压力和熔池的耦合条件下,建立适用于激光焊的三维数学模型。该模型可以描述旋转激光焊接过程中小孔的动态行为特征、流体流动以及气泡在熔池中的形成过程和机理。结果表明,在常规激光焊接中,小孔呈现深而窄且处于不稳定的动态平衡过程,通常会形成气泡。如果气体未能及时溢出熔池,会形成气孔。随着激光旋转频率的增加,小孔变浅变宽,动态行为趋于稳定,可有效抑制气孔的形成。

关键词：旋转激光小孔熔池流动数值模拟

2019—2021学年嘉兴市秀洲区新城街道学生因病缺课监测分析

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中国校医 2024年第3期38卷 191-193,210页

作者：宋梓垚徐雪莉嘉兴市秀洲区新城街道社区卫生服务中心公共卫生科浙江嘉兴314031 嘉兴市秀洲区油车港镇卫生院公共卫生科浙江嘉兴314019

目的分析2019—2021学年嘉兴市秀洲区新城街道内学校学生因病缺课的趋势以及病因,为预防学生疾病发生、降低学校因病缺课率提供依据。方法利用“秀洲区公共卫生协同管理平台学校监测板块”监测2019—2021学年嘉兴市秀洲区新城街道所有... 详细信息

目的分析2019—2021学年嘉兴市秀洲区新城街道内学校学生因病缺课的趋势以及病因,为预防学生疾病发生、降低学校因病缺课率提供依据。方法利用“秀洲区公共卫生协同管理平台学校监测板块”监测2019—2021学年嘉兴市秀洲区新城街道所有幼儿园、中小学学生缺课情况,描述分析学生因病缺课率变化、因病缺课病因构成改变及因病缺课时间分布等。结果2019—2021学年共监测40736人,学生因病缺课率分别为1.97%、2.51%、2.28%,2020学年因病缺课率最高(P<0.05);除幼托学段外,2019—2021学年因病缺课率呈下降趋势(P<0.05),各学段中以幼托学段因病缺课率最高(P<0.05);各学年因病缺课的首位病因是感冒,流行性感冒、水痘及其他疾病发病率呈逐年下降趋势,其他7种疾病呈逐年上升趋势;学生因病缺课高峰主要集中在12月和5月。结论幼托儿童是重点关注人群,呼吸道传染病是学校因病缺课的主要病因。

关键词：学生因病缺课病因

葛花解酒涤脂汤对酒精性肝病小鼠肝脏组织能量代谢的影响

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北京中医药大学学报 2024年第5期47卷 662-671页

作者：刘蕊易旭吴雪莉王硕石何典城游绍伟贵州中医药大学第二附属医院临床医学实验室贵州中医药大学第二附属医院消化内科

目的检测酒精性肝病（ALD）小鼠肝脏组织能量代谢相关指标水平，并探讨葛花解酒涤脂汤的干预作用。方法 40只雄性C57BL/6J小鼠任意分为正常对照组、模型组、葛花解酒涤脂汤高剂量组（4.94 g/kg）、葛花解酒涤脂汤低剂量组（2.47 g/kg... 详细信息

目的检测酒精性肝病（ALD）小鼠肝脏组织能量代谢相关指标水平，并探讨葛花解酒涤脂汤的干预作用。方法 40只雄性C57BL/6J小鼠任意分为正常对照组、模型组、葛花解酒涤脂汤高剂量组（4.94 g/kg）、葛花解酒涤脂汤低剂量组（2.47 g/kg）和白藜芦醇组（0.40 g/kg）,每组8只。除正常对照组外，其他各组小鼠先予Lieber-DeCarli对照液体饲料喂养5 d,随后予Lieber-DeCarli酒精液体饲料喂养10 d,第16天灌胃31.5%乙醇溶液1次，以制备ALD小鼠模型。造模结束后第2天起，各干预组灌胃相应药物，每日1次，连续9 d。苏木素-伊红染色和油红O染色观察肝脏组织脂肪变性情况；分光光度法检测肝脏组织Na+K+-腺苷三磷酸（ATP）酶、Ca2+Mg2+-ATP酶活性，琥珀酸脱氢酶（SDH）、肝糖原含量；反相高效液相色谱法检测肝脏组织ATP、腺苷二磷酸（ADP）和腺苷一磷酸（AMP）含量，以及AMP/ATP值、总腺苷酸池（TAN）含量、能荷值（EC）;实时荧光PCR法检测肝脏组织沉默信息调节因子1（SIRT1）、腺苷酸活化蛋白激酶（AMPK）α2 mRNA表达；蛋白质印迹法检测肝脏组织SIRT1、AMPKα2、AMPKβ1蛋白表达。结果与正常对照组比较，模型组小鼠肝脏组织脂肪变性病变明显，肝脏组织Ca2+Mg2+-ATP酶活性、SDH含量降低，肝糖原含量升高，EC、AMP/ATP值降低，ATP、ADP、AMP和TAN含量升高，SIRT1、AMPKα2 mRNA表达降低，AMPKβ1蛋白表达升高（均P<0.05）。与模型组比较，葛花解酒涤脂汤高、低剂量组肝脏组织脂肪变性明显减轻，肝脏组织Na+K+-ATP酶活性降低，EC及SIRT1、AMPKα2 mRNA表达升高（均P<0.05）;葛花解酒涤脂汤低剂量组Ca2+Mg2+-ATP酶活性、SDH及ATP含量升高（均P<0.05）;葛花解酒涤脂汤高剂量组AMP/ATP值升高（P<0.05）;葛花解酒涤脂汤高、低剂量组和白藜芦醇组肝脏组织SIRT1蛋白表达升高（均P<0.05）;葛花解酒涤脂汤低剂量组和白藜芦醇组AMPKα2蛋白表达升高（均P<0.05）。与葛花解酒涤脂汤高剂量组比较，葛花解酒涤脂汤低剂量组、白藜芦醇组肝脏组织ATP、TAN含量和EC升高，AMP/ATP值降低（均P<0.05）;葛花解酒涤脂汤低剂量组AMPKα2 mRNA表达降低（P<0.05）;白藜芦醇组SIRT1、AMPKα2蛋白表达升高（均P<0.05）。与葛花解酒涤脂汤低剂量组比较，白藜芦醇组AMPKβ1蛋白表达降低（P<0.05）。结论慢性酒精摄入引起的能量代谢改变可能与小鼠ALD发生有关，葛花解酒涤脂汤干预可以改善ALD小鼠肝脏能量代谢异常。

关键词：酒精性肝病葛花解酒涤脂汤能量代谢沉默信息调节因子1 腺苷酸活化蛋白激酶小鼠