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Exploring charge and spin fluctuations in infinite-layer cuprate SrCuO_(2)from a phonon perspective

Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 159-167页

作者： Xin Du pei-Han sun Ben-Chao Gong Jian-Feng Zhang Zhong-Yi Lu Kai Liu Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano Devices Renmin University of ChinaBeijing 100872China Department of Physics School of ScienceJiangsu University of Science and TechnologyZhenjiang 212100China Institute of Physics Chinese Academy of SciencesBeijing 100190China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China

The infinite-layer cuprate ACu O_(2)(A=Ca,Sr,Ba)possesses the simplest crystal structure among numerous cuprate superconductors and can serve as a prototypical system to explore the unconventional *** on the first-principles electronic structure calculations,we have studied the electronic and magnetic properties of the infinite-layer cuprate SrCuO_(2)from a phonon *** find that interesting fluctuations of charges,electrical dipoles,and local magnetic moments can be induced by the atomic displacements of phonon modes in SrCuO_(2)upon the hole *** all optical phonon modes of SrCuO_(2)in the antiferromagnetic Néel state,only the A_(1g)mode that involves the full-breathing O vibrations along the Cu-O bonds can cause significant fluctuations of local magnetic moments on O atoms and dramatic charge redistributions between Cu and O ***,due to the atomic displacements of the A_(1g)mode,both the charge fluctuations on Cu and the electrical dipoles on O show a dome-like evolution with increasing hole doping,quite similar to the experimentally observed behavior of the superconducting T_(c);in comparison,the fluctuations of local magnetic moments on O display a monotonic enhancement along with the hole *** analyses indicate that around the optimal doping,there exists a large softening in the frequency of the A_(1g)phonon mode and a van Hove singularity in the electronic structure close to the Fermi level,suggesting potential electron-phonon *** work reveals the important role of the full-breathing O phonon mode playing in the infinite-layer SrCuO_(2),which may provide new insights in understanding the cuprate superconductivity.

关键词： first-principles calculations cuprate superconductors phonon charge and spin fluctuations

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Biogeochemistry of sedimentary organic matter in the Yongjiang River estuary in the southern part of Hangzhou Bay,China,since the Late Pleistocene

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Journal of Oceanology and Limnology 2024年第3期42卷 772-786页

作者： Dongqin HUANG Xiaolong LI Zilong LI pei sun LOH Jianxiong HU Jianfang CHEN Yuan-Pin CHANG Chin-Wen YANG Qin GAO Institute of Marine Geology and Resources Ocean CollegeZhejiang UniversityZhoushan 316021China Ministry of Water Resources of the People’s Republic of China Beijing 100054China Key Laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Department of Oceanography Sun Yat-sen UniversityKaohsiung 80424China

A sediment core(YJK19-02)collected from the southern outlet of Hangzhou Bay near the Yongjiang River estuary in East China was analyzed for grain size,lignin,bulk elemental composition,stable carbon isotope,and rare earth elements(REEs)to determine the sources and diagenesis of sedimentary organic matter(OM)of the estuary and adjacent areas since the Late Pleistocene.δ^(13)C values(-24.80‰–-23.60‰),total organic carbon/total nitrogen(TOC/TN)molar ratios(8.00–12.14),and light rare earth element/heavy rare earth element ratios(LREE/HREE=8.34–8.91)revealed the predominance of terrestrial sources of OM,mainly from the Changjiang(Yangtze)*** lignin parameters of syringyl/vanillyl(S/V=0.20–0.73)and cinnamyl/vanillyl(C/V=0.03–0.19)ratios indicate the predominance of nonwoody angiosperms,and the vanillic acid/vanillin ratios[(Ad/Al)_(V)=0.32–1.57]indicate medium to high degrees of lignin *** increasing trend ofΛ(total lignin in mg/100-mg OC)values from ca.14500 a BP to ca.11000 a BP reflected the increase in temperature during the Late ***,a time lag effect of temperature on vegetation abundance was also *** relatively higher and stableΛvalues correspond to the higher temperature during the mid-Holocene from ca.8500 a BP to ca.4500 a BP.Λvalues decreased from ca.4000 a BP to the present,corresponding to historical temperature fluctuations during this *** results show that the vegetation abundance in the Yongjiang River Basin since the Late Pleistocene was related to the temperature fluctuation duo to climate change.

关键词： Yongjiang River estuary sedimentary organic matter lignin environmental change Late Pleistocene

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Epidemiology of Leprosy in China,2021:An Update

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International Journal of Dermatology and Venereology 2024年第1期7卷 35-39页

作者： Ying Shi pei-Wen sun Le Wang Hong-Sheng Wang Mei-Wen Yu Heng Gu National Center for Leprosy Control Chinese Center for Disease Control and PreventionHospital for Skin Diseases(Institute of Dermatology)Chinese Academy of Medical Sciences and Peking Union Medical CollegeNanjingJiangsu 210042China

Objective:Leprosy is an infectious diseases that remains a concerning public health *** infection of Mycobacterium leprae still exists at the county level in hard-to-access areas in southwest *** accurate analysis of the prevalence of leprosy in various regions is necessary for the formulation of prevention and control strategies,so we conducted this study to describe the epidemiological characteristics of leprosy in China in 2021 and provide essential information for future national leprosy control and prevention ***:We collected epidemiological data of leprosy from 31 provinces,autonomous regions,and municipalities of China(except for Hong Kong,Macao,and Taiwan)provided by the Leprosy Management Information *** performed a comparative analysis of the epidemiological features of patients with leprosy including age,sex,geographical distribution,and grade of ***:In total,374 newly detected leprosy cases were reported nationwide in China in 2021,giving an incidence rate of 0.27 per million population,which represented a decrease of 7.9%compared with *** the population with leprosy in 2021 that comprised 238 males(63.6%)and 136 females(36.4%),1.9%(7/374)were children younger than 15 years,92.8%(347/374)had multibacillary leprosy,and 18.2%(68/374)had grade 2 *** than half of the new leprosy cases(54.8%,205/374)were distributed in southwest *** were 33 relapsed leprosy cases reported in *** the end of 2021,there were 1,897 registered leprosy cases reported nationwide,giving a prevalence rate of 1.35 per million ***:The leprosy epidemic in China shows a downward trend in terms of the prevalence and incidence ***,the high prevalence of leprosy in southwest China is still a matter of concern.

关键词： epidemiology leprosy China newly detected leprosy cases multibacillary leprosy paucibacillary leprosy incidence rate prevalence rate

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Targeted metabolomics study of fatty-acid metabolism in lean metabolic-associated fatty liver disease patients

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World Journal of Gastroenterology 2024年第27期30卷 3290-3303页

作者： pei-Qi sun Yi-Fu Yuan Qin Cao Xiao-Yan Chen Yuan-Ye Jiang Wen-Min Dong Li-Li Guo Department of Gastroenterology Putuo HospitalShanghai University of Traditional Chinese MedicineShanghai 200062China Department of Pharmacy Shanghai Pudong HospitalFudan University Pudong Medical CenterShanghai 201399China Central Laboratory Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghai 200030China

BACKGROUND The annual incidence of metabolic-associated fatty liver disease(MAFLD)in China has been increasing and is often overlooked owing to its insidious *** 50%of the patients have a normal weight or are not *** are said to have lean-type MAFLD,and few studies of such patients are *** MAFLD is associated with abnormal lipid metabolism,lipid-targeted metabolomics was used in this study to provide experimental evidence for early diagnosis and *** and analyze metabolic ***-Q-Orbitrap/MS content determination was used to determine serum palmitic acid(PA),oleic acid(OA),linoleic acid(LA),and arachidonic acid(AA)levels in lean-type MAFLD *** Urea nitrogen and uric acid levels were higher in lean-type MAFLD patients than in healthy individuals(P*** levels of PA,OA,LA,and AA were significantly increased compared with healthy *** The metabolic profiles of lean-type MAFLD patients and healthy participants differed significantly,yielding 65 identified ***,OA,LA,and AA exhibited the most significant changes,offering valuable clinical guidance for prevention and treatment of lean-type MAFLD.

关键词： Lean-type metabolic-associated fatty liver disease Targeted serum metabolomics Fatty acids Principal component analysis Orthogonal partial least squares-discriminant analysis©The Author(s)2024.Published by Baishideng Publishing Group Inc.All rights reserved.

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Exploring charge and spin fluctuations in infinite-layer cuprate SrCuOfrom a phonon perspective

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Science China(Physics,Mechanics & Astronomy) 2024年

作者： Xin Du pei-Han sun Ben-Chao Gong Jian-Feng Zhang Zhong-Yi Lu Kai Liu Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials & Micro-nano Devices Renmin University of China Department of Physics School of Science Jiangsu University of Science and Technology Institute of Physics Chinese Academy of Sciences Key Laboratory of Quantum State Construction and Manipulation (Ministry of Education) Renmin University of China

The infinite-layer cuprate ACuO2（A = Ca, Sr, Ba） possesses the simplest crystal structure among numerous cuprate superconductors and can serve as a prototypical system to explore the unconventional superconductivity. Based on the first-principles electronic structure calculations, we have studied the electronic and magnetic properties of the infinite-layer cuprate SrCuO2from a phonon perspective. We find that interesting fluctuations of charges, electrical dipoles, and local magnetic moments can be induced by the atomic displacements of phonon modes in SrCuO2upon the hole doping. Among all optical phonon modes of SrCuO2in the antiferromagnetic Ne′el state, only the A1gmode that involves the full-breathing O vibrations along the Cu-O bonds can cause significant fluctuations of local magnetic moments on O atoms and dramatic charge redistributions between Cu and O atoms. Notably, due to the atomic displacements of the A1gmode, both the charge fluctuations on Cu and the electrical dipoles on O show a dome-like evolution with increasing hole doping, quite similar to the experimentally observed behavior of the superconducting Tc; in comparison, the fluctuations of local magnetic moments on O display a monotonic enhancement along with the hole doping. Further analyses indicate that around the optimal doping, there exists a large softening in the frequency of the A1gphonon mode and a van Hove singularity in the electronic structure close to the Fermi level, suggesting potential electron-phonon coupling. Our work reveals the important role of the full-breathing O phonon mode playing in the infinite-layer SrCuO2, which may provide new insights in understanding the cuprate superconductivity.

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一种玉米收获机控制系统的机器学习算法应用

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农机化研究 2024年第3期46卷 190-194页

作者：孙沛成都文理学院信息工程学院成都610401

为进一步提升我国玉米收获机的作业水平、降低其籽粒损失率,基于机器学习算法理念,针对其控制系统展开优化研究。以玉米收获机控制系统的结构组成为基础,恰当地选择对象与目标明确的机器学习算法为应用核心,建立系统的控制模型,同步实... 详细信息

为进一步提升我国玉米收获机的作业水平、降低其籽粒损失率,基于机器学习算法理念,针对其控制系统展开优化研究。以玉米收获机控制系统的结构组成为基础,恰当地选择对象与目标明确的机器学习算法为应用核心,建立系统的控制模型,同步实施系统的硬件配置以满足机器学习算法在进行收获作业时各功能要求的实现,并展开此机器学习算法应用下的玉米收获机作业试验。试验结果表明:经机器学习算法应用前后对比,应用后的玉米收获机控制系统的控制精度相对可提升7.92%,在保证了秸秆切断合格率与苞皮去除率的前提下,实现了籽粒损失率相对降低2.32%的良好控制作业效果,整机作业效率比机器学习算法应用前提升了5.12%,并提高了收获控制精度及收获籽粒完整性。

关键词：玉米收获机机器学习算法控制精度籽粒损失率智能优化

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Bethe ansatz solutions of the 1D extended Hubbard-model

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Communications in Theoretical Physics 2024年第4期76卷 43-50页

作者：侯海洋孙佩乔艺许小甜张鑫杨涛 Institute of Modern Physics Northwest UniversityXian 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xian 710127China Beijing National Laboratory for Condensed Matter Institute of Physics Chinese Academy of SciencesBeijing 100190China

We construct an integrable 1D extended Hubbard model within the framework of the quantum inverse scattering *** the help of the nested algebraic Bethe ansatz method,the eigenvalue Hamiltonian problem is solved by a se... 详细信息

关键词： quantum integrable system Bethe ansatz T-Q relation Hubbard model

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CircRHOT1调节miR-187-3p/SOX4轴对乳腺癌细胞增殖、凋亡和免疫逃逸的影响

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中国免疫学杂志 2024年第3期40卷 577-585页

作者：孙沛姜振伟刘倩武汉市普仁医院检验科武汉430080 武汉市普仁医院肿瘤科武汉430080

目的:研究环状RNA ras同源物基因家族成员T1(CircRHOT1)调节miR-187-3p/性别决定区Y框蛋白4(SOX4)轴对乳腺癌细胞增殖、凋亡和免疫逃逸的影响。方法:采用实时荧光定量PCR和Western blot检测体外培养的人正常乳腺上皮细胞MCF-10A和乳腺... 详细信息

目的:研究环状RNA ras同源物基因家族成员T1(CircRHOT1)调节miR-187-3p/性别决定区Y框蛋白4(SOX4)轴对乳腺癌细胞增殖、凋亡和免疫逃逸的影响。方法:采用实时荧光定量PCR和Western blot检测体外培养的人正常乳腺上皮细胞MCF-10A和乳腺癌细胞MCF-7、Hs-578T、MDA-MB-231中CircRHOT1、miR-187-3p与SOX4表达;将体外培养的MCF-7细胞随机分为对照组、CircRHOT1敲低(转染CircRHOT1 siRNA质粒)组、miR-187-3p mimics(转染miR-187-3p mimics)组、共转染阴性对照(转染空载质粒和miR-187-3p inhibitor阴性对照)组、CircRHOT1敲低+miR-187-3p inhibitor(转染CircRHOT1 siRNA质粒和miR-187-3p inhibitor)组,分组转染后,采用实时荧光定量PCR和免疫印迹检测各组细胞CircRHOT1、miR-187-3p与SOX4表达;采用EdU染色和平板集落形成实验检测各组细胞增殖;采用流式细胞术检测各组细胞凋亡;采用免疫荧光染色检测各组细胞凋亡相关蛋白Bax和Bcl-2表达比值(Bax/Bcl-2)。各组细胞与人外周血淋巴细胞共培养并分组转染后,采用流式细胞术检测各组人外周血淋巴细胞中活化CD8^(+)T细胞比例;采用MTT法检测人外周血淋巴细胞对各组MCF-7细胞的杀伤率。采用双荧光素酶报告实验检测MCF-7细胞CircRHOT1对miR-187-3p、miR-187-3p对SOX4的靶向调控。结果:与人正常乳腺上皮细胞MCF-10A相比,人乳腺癌MCF-7、Hs-578T、MDA-MB-231细胞CircRHOT1、SOX4蛋白与mRNA表达明显升高(P0.05),SOX4蛋白与mRNA表达、EdU阳性率、集落生成率升高(P0.05)。结论:敲低CircRHOT1可通过上调miR-187-3p而降低SOX4表达,从而减弱乳腺癌细胞增殖活性,并促进其凋亡,还可抑制CD8^(+)T细胞活化并增强其癌细胞杀伤力,减弱乳腺癌细胞免疫逃逸。

关键词： CircRHOT1 miR-187-3p/SOX4轴乳腺癌增殖凋亡免疫逃逸

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基于GIS的湖北省建始县生态敏感性空间格局分析

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资源信息与工程 2024年第1期39卷 72-76,81页

作者：孙佩湖北省地质科学研究院湖北武汉430034

生态敏感性评价对于区域经济发展规划、生态环境保护和土地资源的合理利用具有重要的价值。本文选取高程、坡度、坡向、水体、植被覆盖度、道路和土地利用类型7个因子,采用层次分析法(AHP),基于GIS空间分析功能构建生态敏感性评价体系,... 详细信息

生态敏感性评价对于区域经济发展规划、生态环境保护和土地资源的合理利用具有重要的价值。本文选取高程、坡度、坡向、水体、植被覆盖度、道路和土地利用类型7个因子,采用层次分析法(AHP),基于GIS空间分析功能构建生态敏感性评价体系,获得各单因子及综合的生态敏感性空间分布与统计情况。结果表明:湖北省建始县生态以中度敏感性为主,中度敏感区主要分布于中部,总面积约1084.15 km^(2),占比40.68%;以水域为主的高度敏感区在东南与东北部较为集中,面积约751.70 km^(2),占比28.21%;以耕地与草地为主的轻度低敏感区主要分布在西北部,总面积约657.66 km^(2),占比24.68%;以林地与园地为主的极高敏感区和以建设用地为主的极低敏感区面积均较小,分别为157.39和13.85 km^(2),占比分别为5.91%和0.52%。

关键词：生态敏感性层次分析法 GIS空间分析建始县

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孟鲁司特钠联合阿奇霉素治疗小儿支原体肺炎的效果

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中外医药研究 2024年第20期3卷 57-59页

作者：孙佩安顺市西秀区人民医院贵州安顺561000

目的:分析孟鲁司特钠联合阿奇霉素治疗支原体肺炎的临床效果。方法:选取2021年5月—2022年5月安顺市西秀区人民医院收治的支原体肺炎患儿80例为研究对象,采用随机数字表法分为参照组和观察组,各40例。参照组采用阿奇霉素治疗,观察组采... 详细信息

目的:分析孟鲁司特钠联合阿奇霉素治疗支原体肺炎的临床效果。方法:选取2021年5月—2022年5月安顺市西秀区人民医院收治的支原体肺炎患儿80例为研究对象,采用随机数字表法分为参照组和观察组,各40例。参照组采用阿奇霉素治疗,观察组采用孟鲁司特联合阿奇霉素治疗。比较两组治疗总有效率、炎性因子[C反应蛋白(CRP)、降钙素原(PCT)]水平、症状消失时间及不良反应发生率。结果:观察组治疗总有效率高于参照组,差异有统计学意义(P=0.013)。治疗前,两组CRP、PCT水平比较,差异无统计学意义(P>0.05);治疗后,两组CRP、PCT水平低于治疗前,观察组低于参照组,差异有统计学意义(P0.05)。结论:孟鲁司特钠联合阿奇霉素治疗支原体肺炎的效果较好,可减轻机体炎性反应,改善临床症状,不良反应较少。

关键词：支原体肺炎孟鲁司特钠阿奇霉素炎性因子

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