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新疆大学学报（自然科学版中英文） 2024年第3期41卷 288-295页

作者：何明霞王静兰州文理学院教育学院甘肃兰州730010

研究了一类具有无穷时滞和瞬时脉冲的积微分方程的最优化控制问题.利用分数幂算子、相空间理论、Gronwall不等式和不动点定理得到了在空间解的存在性的充分条件,然后使用最小化序列给出了积分成本函数的最优化控制的充分条件.

关键词：最优控制无穷时滞瞬时脉冲 mild解

Coastal upwelling observed by multi-satellite sensors

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Science China Earth Sciences 2009年第7期52卷 1030-1038页

作者： LI XiaoMing LI XiaoFeng he mingxia Ocean Remote Sensing Institute Ocean University of ChinaQingdao 266003China IMSG at NOAA/NESDIS 5200 Auth RoadWWB/102Camp SpringsMD 20746USA

Coastal upwelling phenomenon along the China coast in the Yellow Sea during August 2007 is studied using ENVISAT Advanced Synthetic Aperture Radar (ASAR) data, NOAA Advanced AVHRR series Sea Surface Temperature (SST) data,and NASA QuikSCAT Scatterometer ocean surface wind data. A dark pattern in an ASAR image is interpreted as coastal upwelling. This is because the natural biogenic slicks associated with coastal upwelling damp the Bragg waves on the sea surface and thus make the surface smoother. Most of the incoming radar energy is reflected in the forward direction. As a result, the radar backscatter signal is very weak. Analyzing the concurrent AVHRR SST image, we find that the dark pattern in the ASAR image is indeed corresponding to the low SST area. The wind retrieval in the slicks dominant region is biased due to the low Normalised Radar Cross Section (NRCS) associated with the coastal upwelling. We applied a SST correction to the NRCS values to improve the accuracy of wind retrieval from ASAR data.

关键词： coastal upwelling SAR AVHRR/SST wind field retrieval

Speckle suppression in synthetic aperture radar ocean internal solitary wave images with curvelet transform

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Acta Oceanologica Sinica 2016年第9期35卷 13-21页

作者： ZHA Guozhena he Qingyou GUAN Changlonga SUN Jian he mingxia College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China University of Chinese Academy of Sciences Beijing 100049China Physical Oceanography Laboratory Ocean University of ChinaQingdao 266100China Ocean Remote Sensing Institute Ocean University of ChinaQingdao 266100China

This paper proposes a speckle-suppression method for ocean internal solitary wave（ISW） synthetic aperture radar（SAR） images by using the curvelet *** band-shaped signatures of ocean ISWs in SAR images show obvious scale and directional *** curvelet transform possesses a very high scale and directional ***,the curvelet transform is very efficient in analyzing wave signals in SAR images.A noisy ocean ISW SAR image can be decomposed at different scales,directions,and positions using the curvelet *** information of the ISWs is centralized in the curvelet coefficients of certain directions under certain scales,whereas the speckle noise is distributed in every scale and *** manipulating the curvelet coefficients,the signals of the ISWs can be extracted from the noisy SAR ***,the speckle noise is suppressed and the ISW feature is enhanced by adding the signals of the ISWs back to the original SAR *** demonstrate the effectiveness of this method.

关键词： curvelet transform internal solitary wave remote sensing speckle noise synthetic aperture radar

Performance evaluation of operational atmospheric correction algorithms over the East China Seas

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Chinese Journal of Oceanology and Limnology 2017年第1期35卷 1-22页

作者： he Shuangyan[l,2,3] he mingxia FISCheR Jurgen Ocean Remote Sensing Institute Ocean University of China Qingdao 266003 China Institute for Space Sciences Freie Universitdt Berlin Berlin D-12165 Germany Ocean College Zhejiang University Hangzhou 310058 China

To acquire high-quality operational data products for Chinese in-orbit and scheduled ocean color sensors, the performances of two operational atmospheric correction(AC) algorithms(ESA MEGS 7.4.1 and NASA Sea DAS 6.1) were evaluated over the East China Seas(ECS) using MERIS data. The spectral remote sensing reflectance R_(rs)(λ), aerosol optical thickness(AOT), and ?ngstr?m exponent(α) retrieved using the two algorithms were validated using in situ measurements obtained between May 2002 and October 2009. Match-ups of R_(rs), AOT, and α between the in situ and MERIS data were obtained through strict exclusion criteria. Statistical analysis of R_(rs)(λ) showed a mean percentage difference(MPD) of 9%–13% in the 490–560 nm spectral range, and significant overestimation was observed at 413 nm(MPD>72%). The AOTs were overestimated(MPD>32%), and although the ESA algorithm outperformed the NASA algorithm in the blue-green bands, the situation was reversed in the red-near-infrared bands. The value of α was obviously underestimated by the ESA algorithm(MPD=41%) but not by the NASA algorithm(MPD=35%). To clarify why the NASA algorithm performed better in the retrieval of α, scatter plots of the α single scattering albedo(SSA) density were prepared. These α-SSA density scatter plots showed that the applicability of the aerosol models used by the NASA algorithm over the ECS is better than that used by the ESA algorithm, although neither aerosol model is suitable for the ECS region. The results of this study provide a reference to both data users and data agencies regarding the use of operational data products and the investigation into the improvement of current AC schemes over the ECS.

关键词： validation remote sensing reflectance aerosol optical thickness ocean color atmospheric correction remote sensing

heterologous expression of Hp BHY and Cr BKT increases heat tolerance in Physcomitrella patens

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Plant Diversity 2019年第4期41卷 266-274页

作者： Jianfang he Ping Li heqiang Huo Lina Liu Ting Tang mingxia he Junchao Huang Li Liu Key Laboratory of Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesYunnan Key Laboratory for Wild Plant ResourcesKunming650201China University of Chinese Academy of Sciences Beijing100049China Mid-Florida Research and Education Center Department of Environmental HorticultureUniversity of FloridaFL32703USA

heat stress can restrict plant growth,development,and crop *** essential plant antioxidants,carotenoids play significant roles in plant stress resistance.b-carotene hydroxylase(BHY)and b-carotene ketolase(BKT),which catalyze the conversions of b-carotene to zeaxanthin and b-carotene to canthaxanthin,respectively,are key enzymes in the carotenoid biosynthetic pathway,but little is known about their potential functions in stress ***,we investigated the roles of b-carotene hydroxylase and b-carotene ketolase during heat stress in Physcomitrella patens through expressing a b-carotene ketolase gene from Chlamydomonas reinhardtii(Cr BKT)and a b-carotene hydroxylase gene from Haematococcus pluvialis(Hp BHY)in the moss *** transgenic moss expressing these genes,carotenoids content increased(especially lutein content),and heat stress tolerance increased,with reduced leafy tissue *** investigate the mechanism of this heat stress resistance,we measured various physiological indicators and found a lower malondialdehyde level,higher peroxidase and superoxide dismutase activities,and higher endogenous abscisic acid and salicylate content in the transgenic plants in response to high-temperature *** results demonstrate that Cr BKT and Hp BHY increase plant heat stress resistance through the antioxidant and damage repair metabolism,which is related to abscisic acid and salicylate signaling.

关键词： Carotenoids heat stress Antioxidant Abscisic acid Physcomitrella patens

Terahertz spectral properties of melamine and its deuterated isotope,melamine-d_6

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Nuclear Science and Techniques 2012年第4期23卷 209-214页

作者： he mingxia LI Meng TIAN Zhen CAO Wei HAN Jiaguang Center for Terahertz Waves and College of Precision Instrument and Optoelectronics Engineering Tianjin UniversityTianjin 300072China School of Electrical and Computer Engineering Oklahoma State UniversityStillwaterOklahoma 74078USA

The far-infrared optical properties of melamine and its deuterated isotope,melamine-d_6 were experimentally and theoretically investigated in the frequency range from 0.2 to 3.0 *** the room temperature and dry air nitrogen conditions,three absorption bands were observed at 2.0,2.3 and 2.6 THz in the melamine sample by use of terahertz time-domain ***,in the melamine-d_6 sample,the observed absorption bands shift towards lower frequencies and the relative intensity of the absorption bands *** simulation results based on the Parameterized Model number 3(PM3) were compared with the experimental data and the observed vibration spectra were assigned according to the PM3 *** absorption bands of the measured melamine samples at terahertz frequencies are highly correlated with the intermolecular hydrogen bond stretching and π-π stacking ***,the red shift of the absorption bands is due to hydrogen/deuterium substitution.

关键词：太赫兹时域光谱三聚氰胺氘同位素光谱特性分子间氢键频率范围实验数据吸收带

Adsorption of trichlorphon on phyllosilicate minerals:Effect of low-molecular-weight organic acids

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Pedosphere 2024年第1期34卷 78-87页

作者： Hongfeng CheN Zhouyang he mingxia HOU Cilai TANG Yonghong WU College of Hydraulic&Environmental Engineering China Three Gorges UniversityYichang 443002China Hubei Field Observation and Scientific Research Stations for Water Ecosystem in Three Gorges Reservoir China Three Gorges UniversityYichang 443002China Engineering Research Center of Eco-Environment in Three Gorges Reservoir Region China Three Gorges UniversityYichang 443002China State Key Laboratory of Soi and Sustainable Agriculture Institute of Soil SciencesChinese Academy of SciencesNanjing 210008China

The use of trichlorphon in large quantities causes a large number of organic pollutants to enter water, sediments, and soils. Phyllosilicate minerals are considered effective adsorbents for organic pollutants. However, the adsorption behavior of organic pollutants on soil minerals affected by low-molecular-weight organic acids(LMWOAs) is not fully understood. In this study, the effect of LMWOAs on the adsorption behavior of trichlorphon on phyllosilicate minerals was investigated using a combination of adsorption measurements and molecular spectroscopic techniques(attenuated total reflection-Fourier transform infrared spectroscopy(ATR-FTIR) and X-ray photoelectron spectroscopy(XPS)). The adsorption of trichlorphon onto kaolinite(KAO) and montmorillonite(MON) was suppressed by increasing pH, indicating that electrostatic interaction played a key role in adsorption, especially at low pH. In the presence of citric acid(CA), there was an obvious promotion of trichlorphon adsorption on KAO and MON. In the presence of oxalic acid(OA), the adsorption of trichlorphon on KAO was promoted, whereas the adsorption on MON was inhibited, especially at pH 4.0. The presence of CA and OA increased the adsorption by increasing the exposure of hydrophobic sites of KAO and MON. The results from ATR-FTIR and XPS also indicated that the hydrophobic Si–O sites of phyllosilicate minerals were the preferred adsorption sites for trichlorphon in the presence of CA and OA, probably driven by the hydrophobic effect. However, the weak effect of OA on MON caused an increase in the electrostatic repulsion between MON and trichlorphon molecules, thus inhibiting adsorption. This study is significant for a deeper understanding of self-purification of soil and sediment systems in the presence of organic pollutants.

关键词： adsorption behavior citric acid hydrophobic effect organic pesticide organic pollutant organochlorine oxalic acid

乌司奴单抗在溃疡性结肠炎患者中的有效性和安全性:真实世界研究的荟萃分析

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胃肠病学和肝病学杂志 2024年第6期33卷 685-691页

作者：张朝柱刘宁纪粟敖建萍何明霞中国人民解放军陆军第九五一医院消化内科新疆库尔勒841000 中国人民解放军陆军第九五一医院心胸神经外科新疆库尔勒841000 中国人民解放军陆军第九五一医院介入医学中心新疆库尔勒841000

目的通过荟萃分析探究乌司奴单抗(Ustekinumab,UST)治疗溃疡性结肠炎(ulcerative colitis,UC)的安全性和有效性。方法检索Medline、EmBase、PubMed、万方数据库,对真实世界研究进行系统综述和Meta分析,评价UST治疗UC的安全性和有效性。... 详细信息

目的通过荟萃分析探究乌司奴单抗(Ustekinumab,UST)治疗溃疡性结肠炎(ulcerative colitis,UC)的安全性和有效性。方法检索Medline、EmBase、PubMed、万方数据库,对真实世界研究进行系统综述和Meta分析,评价UST治疗UC的安全性和有效性。结果共纳入11项研究(3384例患者),其中97.1%的UC患者曾接受生物制剂治疗。在12周诱导缓解期,UST治疗UC的临床应答率为61%,临床缓解率为34%,无激素缓解率为38%。维持缓解期24周时,临床缓解率为39%,无激素缓解率为40%。1年后,临床缓解率为37%,无激素缓解率为37%。UC患者中不良事件发生率为5%。发表偏倚评价结果显示无显著异质性。结论UST是治疗UC有效且安全的药物之一。对于中重度UC患者,特别是拒绝手术治疗的患者,考虑使用UST治疗可能会取得较好的疗效。

关键词：乌司奴单抗溃疡性结肠炎真实世界研究荟萃分析生物制剂

基于蛋白质结构知识解析活性多肽的酶解制备反应行为(Ⅰ)酶解反应动态特性的3-D图形表征

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化工学报 2005年第12期56卷 2387-2391页

作者：齐崴何志敏何明霞天津大学化工学院化学工程研究所天津300072

提出了一种基于生物信息学知识与凝胶排阻色谱技术及图形拟合处理相结合的生物大分子复杂酶解反应行为定量分析、直观表征及模拟解析的新方法.研究中以全酪蛋白胰蛋白酶为模式水解体系,根据完整的HPSEC实验谱图,经分子模拟多肽结构,获... 详细信息

提出了一种基于生物信息学知识与凝胶排阻色谱技术及图形拟合处理相结合的生物大分子复杂酶解反应行为定量分析、直观表征及模拟解析的新方法.研究中以全酪蛋白胰蛋白酶为模式水解体系,根据完整的HPSEC实验谱图,经分子模拟多肽结构,获得了大量产物多肽信息;绘制了表征酶解反应动态特性的3D曲面图与21/2维伪彩色图,并对拟合曲面方程进行了数学分析,为调控酶解反应、定向和定量地高效获取目标活性多肽提供了理论依据.

关键词：酶解 3-D图形曲面拟合动态表征活性多肽蛋白质结构高效凝胶排阻色谱

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外语教育:赋能“让世界读懂中国”的路径

外语电化教学 2022年第6期 59-64页

作者：何明霞湖北经济学院外国语学院湖北省武汉市430205

外语教育承载着传承弘扬中华文化,“让世界读懂中国”,引导国际舆论,塑造国家形象,推动中华文化创造性转化、创新性发展的重任。强化外语教育的政治性、工具性、人文性、实践性、系统性,将“让世界读懂中国”摆在外语教育的重要位置,讲... 详细信息

外语教育承载着传承弘扬中华文化,“让世界读懂中国”,引导国际舆论,塑造国家形象,推动中华文化创造性转化、创新性发展的重任。强化外语教育的政治性、工具性、人文性、实践性、系统性,将“让世界读懂中国”摆在外语教育的重要位置,讲好中国故事,传播中国声音,全面落实党的教育方针,构建外语教育三大体系,破解外语教育三大难题,提升国际话语权,提高外语教育效率,推动外语教育治理现代化,是外语教育赋能“让世界读懂中国”的有益尝试,对提升国家外语能力和文化软实力具有重要意义。

关键词：外语教育读懂中国课程思政讲好中国故事