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前期东北大西洋-地中海西部海温异常影响河南省干热风的可能途径

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高原气象 2025年第1期44卷 150-162页

作者：竹磊磊苏晓乐潘攀吴璐杨婷中国气象局•河南省农业气象保障与应用技术重点开放实验室河南郑州450003 河南省气候中心河南郑州450003

河南省是中国冬小麦的主产区,也是较易受干热风影响的地区。目前对干热风的研究和预报多在天气尺度,从气候的角度研究干热风是否具有可预报性,具有非常重要的意义。本文基于河南省干热风资料、nCEP/nCAR再分析资料和哈得莱环流中心海温... 详细信息

河南省是中国冬小麦的主产区,也是较易受干热风影响的地区。目前对干热风的研究和预报多在天气尺度,从气候的角度研究干热风是否具有可预报性,具有非常重要的意义。本文基于河南省干热风资料、nCEP/nCAR再分析资料和哈得莱环流中心海温资料,分析了1980-2022年前期海温异常与河南省干热风日数的关系,及其可能影响途径。结果表明:(1)豫北、豫西北和豫中多年平均干热风日数较多,其他地区则相对较少。日干热风出现的概率由南向北、由5月下旬至6月上旬逐渐增加。全省平均干热风日数有显著增加趋势。(2)河南省干热风日数与当年3-4月东北大西洋-地中海西部(关键区)海温在年代际和年际尺度上均存在着密切相关,两者与干热风发生时段500 hPa高度场在去趋势前和去趋势后的显著正相关区在东亚中纬度地区位于新疆北部至贝加尔湖尔湖北部,显著负相关区位于我国东北至日本群岛附近,与850 hPa风场在去趋势前和去趋势后的相关在上述正、负显著相关区分别呈反气旋和气旋分布,气旋后部呈偏北风的显著相关,即3-4月关键区高海温年,出现的蒙古高压脊和东亚大槽造成了河南省的干热风天气。海温与环流场的相关在去趋势前和去趋势后在中纬度地区呈现出一个更明显的由东北大西洋经欧亚大陆至东北亚的纬向遥相关波列。(3)西太平洋副热带高压(以下简称副高)偏南(北)时,干热风日数易偏多(少),而3-4月关键区高(低)海温则可以导致副高偏南(北)。(4)干热风偏多年和偏少年、3-4月关键区高海温年和低海温的干热风发生时段30°n-55°n经向平均的涡度差值,及高、低海温年的干热风发生时段500 hPa准地转流函数距平和波作用通量均显示在中纬度地区存在自东北大西洋至东北亚的纬向波列。也即表明,3-4月关键区海温可以激发出一个后期干热风发生时段的类似波列,经欧亚大陆传至东北亚,而高海温年在东亚中纬度地区的环流分布造成了河南省的干热风天气。

关键词：干热风东北大西洋地中海西部海温遥相关波列

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Friction and Deformation Behavior of Human Skin During Robotic Sliding Massage Operation

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Journal of Bionic Engineering 2024年第4期21卷 1892-1904页

作者： Jingmei Zhai Rixing Li Ziqing su School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou510000China

This study investigates the friction and deformation behavior of the skin in contact with a rigid massage ball and its influencing *** and stretching experiments were conducted using a collaborative robot experimental *** experiments encompassed a loading normal force range of 2 n to 18 n and a sliding speed range of 10 mm/s to 20 mm/*** friction response curve exhibits two different stages:static stick state and dynamic stick-slip stage,both of which have been mathematically *** analyzing the experimental data,we analyzed the effects of elastic modulus,sliding speed and normal loading force on skin tangential friction and tensile *** results indicate that as the normal load increases,both friction and deformation exhibit an ***,they decrease with an increase in elastic ***,while deformation diminishes with higher sliding speed,friction force remains relatively unaffected by *** observation can be attributed to the strain rate sensitivity resulting from the viscoelastic characteristics of the skin under substantial *** study advances the understanding of friction and deformation behavior during skin friction,offering valuable insights to enhance the operational comfort of massage robots.

关键词： Human skin Friction sliding Deformation Robotic massage Stereo image

Establishment of a Gene Expression System in Rice Chloroplast and Obtainment of PPT-Resistant Rice Plants

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Agricultural Sciences in China 2009年第6期8卷 643-651页

作者： LI Yi-nü sun Bing-yao su ning MEnG Xiang-xun ZHAnG Zhi-fang SHEn Gui-fang Biotechnology Research Institute Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China College of Life Sciences Suzhou University Suzhou 215123 P.R.China Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China

In contrast to the situation of random integration of foreign genes in nuclear transformation, the introduction of genes via chloroplast genetic engineering is characterized by site-specific pattern via homologous recombination. To establish an expression system for alien genes in rice chloroplast, the intergenic region of ndhF and trnL was selected as target for sitespecific integration of PPT-resistant bar gene in this study. Two DnA fragments suitable for homologous recombination were cloned from rice chloroplast genome DnA using PCR technique, and the chloroplast-specific expression vector pRB was constructed by fusing a modified 16S rRnA gene promoter to bar gene together with terminator ofpsbA gene 3 sequence. Chloroplast transformation was carried out by biolistic bombardment of sterile rice calli with the pRB construct. subsequently, the regenerated plantlets and seeds of progeny arising from reciprocal cross to the wild-type lines were obtained. Molecular analysis suggested that the bar gene has been integrated into rice chloroplast genome. Genetic analysis revealed that bar gene could be transmitted and expressed normally in chloroplast genome. Thus, the bar gene conferred not only selection pressure for the transformation of rice chloroplast genome, but PPT-resistant trait for rice plants as well. It is suggested that an efficient gene expression system in the rice chloroplast has been established by chloroplast transformation technique.

关键词： Oryza sativa L. chloroplast transformation bar gene homologous fragments

Digitizing the thermal and hydrological parameters of land surface in subtropical China using AMSR-E brightness temperatures

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International Journal of Digital Earth 2017年第7期10卷 687-700页

作者： Yongxian su Xiuzhi Chen Hua su Liyang Liu Jishan Liao Key Lab of Guangdong for Utilization of Remote Sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and ApplicationGuangzhou Institute of GeographyGuangzhouPeople’s Republic of China Jiangsu Key Laboratory of Agricultural Meteorology College of Applied MeteorologyNanjing University of Information Science and TechnologyNanjingPeople’s Republic of China Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of SciencesGuangzhouPeople’s Republic of China Key Laboratory of Spatial Data Mining and Information Sharing of Ministry of Education National Engineering Research Centre of Geo-spatial Information TechnologyFuzhou UniversityFuzhouPeople’s Republic of China

Digitizing the land surface temperature(T_(s))and surface soil moisture(m _(v))is essential for developing the intelligent Digital ***,we developed a two parameter physical-based passive microwave remote sensing model for jointly retrieving T_(s) and m_(v) using the dual-polarized T_(b) of Aqua satellite advanced microwave scanning radiometer(AMSR-E)C-band(6.9 GHz)based on the simplified radiative transfer *** using in situ T_(s) and m_(v) in southern China showed the average root mean square errors(RMSE)of T s and m_(v) retrievals reach 2.42 K(R^(2)=0.61,n=351)and 0.025 g cm^(−3)(R^(2)=0.68,n=663),*** results were also validated using global in situ T_(s)(n=2362)and m_(v)(n=1657)of International Soil Moisture *** corresponding RMSE are 3.44 k(R 2=0.86)and 0.039 g cm^(−3)(R^(2)=0.83),*** monthly variations of model-derived Ts and mv are highly consistent with those of the Moderate Resolution Imaging Spectroradiometer T_(s)(R^(2)=0.57;RMSE=2.91 k)and ECV_SM m_(v)(R^(2)=0.51;RMSE=0.045 g cm^(−3)),***,this paper indicates an effective way to jointly modeling T_(s) and m_(v) using passive microwave remote sensing.

关键词： surface soil moisture land surface temperature physical-based radiative transfer model AMSR-E brightness temperatures

The Signature of Generalized Flag Manifolds and Applications

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Acta Mathematica Sinica,English Series 2010年第8期26卷 1457-1462页

作者： Ping LI Yang su Department of Mathematics Tongji University Shanghai 200092 P. R. China Institute of Mathematics Academy of Mathematics and System Science Chinese Academy of Sciences Beijing 100190 P. R. China

Let G be a linear algebraic group over C and P be a parabolic subgroup. We determine the signatures of the flag manifold G/P. As an application, we prove that the nonsingular hypersurfaces of degree 2 in CP^n are prim... 详细信息

关键词： Signature flag manifold prime manifold

阿戈美拉汀缓解APP/PS1转基因小鼠焦虑及抑郁样行为的机制

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中国组织工程研究 2025年第6期29卷 1176-1182页

作者：李甜任俞桦高艳萍苏强山西医科大学基础医学院生理学系细胞生理学教育部重点实验室细胞生理学山西省重点实验室山西省太原市030001 山西医科大学汾阳学院医学检验系山西省汾阳市032200

背景:阿戈美拉汀在临床上用于治疗焦虑、抑郁等相关精神行为异常。前期研究证实,阿戈美拉汀能够有效缓解阿尔茨海默病模型小鼠的认知行为、海马突触可塑性及脑病理特征,然而阿戈美拉汀能否改善阿尔茨海默病模型小鼠的焦虑和抑郁样行为... 详细信息

背景:阿戈美拉汀在临床上用于治疗焦虑、抑郁等相关精神行为异常。前期研究证实,阿戈美拉汀能够有效缓解阿尔茨海默病模型小鼠的认知行为、海马突触可塑性及脑病理特征,然而阿戈美拉汀能否改善阿尔茨海默病模型小鼠的焦虑和抑郁样行为仍不清楚。目的:探究阿戈美拉汀对APP/PS1(阿尔茨海默病)转基因小鼠焦虑和抑郁样行为的改善效应及分子机制。方法:①将18只APP/PS1转基因小鼠随机分为模型对照组(n=9)、模型干预组(n=9),将18只野生型小鼠随机分为对照组(n=9)、干预组(n=9),模型干预组与干预组小鼠腹腔注射阿戈美拉汀10 mg/(kg·d),连续注射31 d后进行高架十字迷宫、强迫游泳行为学实验与海马组织mRnA测序。②取小鼠海马神经元细胞株(HT22)、脑微血管内皮细胞株(bEnd.3),分别分4组培养:空白组不加入任何药物,药物组加入20µmol/L阿戈美拉汀,模型组加入10µmol/Lβ-淀粉样蛋白1-42,实验组加入10µmol/Lβ-淀粉样蛋白1-42+20µmol/L阿戈美拉汀,培养24 h后,免疫印迹检测HT22细胞S416p-tau和S9p-GSK3β的蛋白表达,免疫印迹检测bEnd.3细胞低密度脂蛋白受体相关蛋白1、糖基化终产物受体的蛋白表达。结果与结论:①在高架十字迷宫实验中,模型对照组小鼠的探索开放臂时间与开放臂进入次数均少于对照组(PnA测序显示,阿戈美拉汀可以增强APP/PS1小鼠海马区低密度脂蛋白受体相关蛋白1的表达。②免疫印迹检测显示,模型组HT22细胞S416p-tau蛋白表达高于空白组(Pnd.3细胞低密度脂蛋白受体相关蛋白1蛋白表达高于模型组(P<0.05)。③结果表明,阿戈美拉汀可通过促进脑内β-淀粉样蛋白和tau的清除来缓解阿尔茨海默病小鼠的焦虑和抑郁样行为。

关键词：阿尔茨海默病阿戈美拉汀 APP/PS1转基因小鼠焦虑抑郁

Transition prediction of the supersonic boundary layer on a cone under the consideration of receptivity to slow acoustic waves

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Science China(Physics,Mechanics & Astronomy) 2011年第10期54卷 1875-1882页

作者： su CaiHong ZHOU Heng Department of Mechanics Tianjin University Tianjin 300072 China Tianjin Key Laboratory of Modern Engineer Mechanics Tianjin 300072 China

Transition prediction of the supersonic boundary layer on a cone with small angle of attack and Mach number 3.5 is investi-gated under the consideration of receptivity to slow acoustic waves, as the acoustic waves are the main environmental distur-bances in a conventional, i.e. non-quiet, wind tunnel. It is shown that the e-n method can still yield fairly satisfactory results incomparison with those obtained in wind tunnel experiments, provided that the boundary layer receptivity to slow acousticwaves is properly taken into account, including the dependence of the amplitude of disturbances on the frequency andstream-wise location. neither the conventional e-n method nor the improved e-n method can yield correct result of transitionprediction, because the receptivity mechanisms considered there are not in accord with the real situation in the wind tunnel.

关键词： receptivity boundary layer transition cone e-n method

Hardy type estimates for commutators of singular integrals

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Science China Mathematics 2005年第4期48卷 563-575页

作者： sun Yongzhong su Weiyi IMS and Department of Mathematics Nanjing Univetsity Nanjing210093 China IMS and Department of Mathematics Nanjing Univetsity Nanjing210093 China

In this paper we study the Hardy type estimates for commutators Tb of standard Calder(o)n-Zygmund singular integral operators T with a Lipschitz function b. The corresponding results are also obtained on the commutato... 详细信息

关键词： Calder(o)n-Zygmund singular integrals,commutators, Lipschitz type spaces, Hardy type spaces, singular integrals with variable kernels.

Effects of cathode potentials and nitrate concentrations on dissimilatory nitrate reductions by Pseudomonas alcaliphila in bioelectrochemical systems

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Journal of Environmental Sciences 2014年第4期26卷 885-891页

作者： Wenjie Zhang Yao Zhang Wentao su Yong Jiang Min su Ping Gao Daping Li College of Life Sciences Sichuan University Key Laboratory of Environmental and Applied Microbiology Chengdu Institute of Biology Chinese Academy of Sciences Environmental Microbiology Key Laboratory of Sichuan Province

The effects of cathode potentials and initial nitrate concentrations on nitrate reduction in bio- electrochemical systems （BESs） were reported. These factors could partition nitrate reduction between denitrification and dissimilatory nitrate reduction to ammonium （DnRA）. Pseudomonas alcaliphilastrain MBR utilized an electrode as the sole electron donor and nitrate as the sole electron acceptor. When the cathode potential was set from -0.3 to -I.1 V （vs. Ag/AgC1） at an initial nitrate concentration of 100 mg nO^-n/L, the DnRA electron recovery increased from （10.76 ± 1.6）% to （35.06 ± 0.99）%; the denitrification electron recovery decreased from （63.42 ± 1,32）% to （44.33 ± 1.92）%. When the initial nitrate concentration increased from （29.09 ± 0.24） to （490.97 ± 3.49） mg nO3-n/L at the same potential （-0.9 V）, denitrification electron recovery increased from （5.88 ± 1.08）% to （50.19 ±2.59）%; the DnRA electron recovery declined from （48.79 ±1.32）% to （16.02 ± 1.41）%. The prevalence of DnRA occurred at high ratios of electron donors to acceptors in the BESs and denitrification prevailed against DnRA under a lower ratio of electron donors to acceptors. These results had a potential application value of regulating the transformation of nitrate to n2 or ammonium in BESs for nitrate removal.

关键词： bioelectrochemical systems cathode potential Pseudomonas alcaliphila MBR denitrification dissimilatory nitrate reduction