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喀斯特山地城市景观格局对城市内涝的影响研究——以贵阳市为例

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贵州师范大学学报（自然科学版） 2024年第2期42卷 53-61页

作者：戴丽尹昌应毛春艳郑佳薇贵州师范大学地理与环境科学学院贵州贵阳550025 贵州省山地资源与环境遥感应用重点实验室贵州贵阳550025 贵州理工学院建筑与城市规划学院贵州贵阳550003

全球气候变化背景下,随着城镇化高速发展,城市内涝灾害愈加明显,已成为造成喀斯特地区损失较为严重的灾害之一。选择西南喀斯特山地城市——贵阳市为研究区,基于2016—2020年实测和调查的内涝灾害数据,运用空间自相关和相关分析方法,探... 详细信息

全球气候变化背景下,随着城镇化高速发展,城市内涝灾害愈加明显,已成为造成喀斯特地区损失较为严重的灾害之一。选择西南喀斯特山地城市——贵阳市为研究区,基于2016—2020年实测和调查的内涝灾害数据,运用空间自相关和相关分析方法,探究景观格局对城市内涝的影响。结果表明:1)2016—2020年贵阳市主城区内涝频发,且空间分布差异性显著,呈现显著的空间自相关和集聚分布特征。2)不透水面、绿地与内涝频次的相关性显著,分别呈正、负相关。3)内涝周边500 m缓冲区内景观由少数聚集程度大的斑块构成,优势度较高,景观中的优势斑块类型仅有一种或少量几种;不同土地利用类型的景观格局空间聚集情况差异显著,其中铁路与道路、房屋建筑的景观指数空间聚类较为显著。4)内涝与土地利用类型面积的关系不显著,但与土地利用类型的景观指数有显著相关性,且不同土地利用景观格局对内涝的影响差异较大。研究结果为喀斯特城市内涝防治和景观格局规划管理提供重要参考和借鉴意义。

关键词：喀斯特山地城市空间自相关土地利用景观格局指数相关分析

融媒体大型活动直播中的供电系统保障与安全防范

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电视技术 2024年第7期48卷 6-11页

作者：郑佳蔚高永飞浙江广播电视集团浙江杭州310000

探讨在直播技术快速发展的当下,融媒体大型直播中电力供给的重要性以及可能发生的安全问题,基于浙江广播电视集团省委重要活动保障专班的实践经验,详细介绍大型直播活动供电系统的安保思路,为技术人员在规划和执行大型直播活动中的供电... 详细信息

探讨在直播技术快速发展的当下,融媒体大型直播中电力供给的重要性以及可能发生的安全问题,基于浙江广播电视集团省委重要活动保障专班的实践经验,详细介绍大型直播活动供电系统的安保思路,为技术人员在规划和执行大型直播活动中的供电保障及进一步提升供电系统的安全性和可靠性提供参考依据。

关键词：融媒体直播供电安全应急保障供电系统设计电力安全

利用GNSS历元间差分测速方法反演地震三要素

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测绘地理信息 2024年第1期49卷 62-66页

作者：胡星辉方荣新郑佳伟吕黄晖武汉大学测绘学院湖北武汉430079 武汉大学卫星导航定位技术研究中心湖北武汉430079

利用高频全球卫星导航系统(global navigation satellite system,GNSS)记录监测地震可有效弥补传统地震仪近场观测量程饱和、基线偏移等问题。相比于GNSS精密单点定位(precise point positioning,PPP),历元间差分测速方法可避免PPP收敛... 详细信息

利用高频全球卫星导航系统(global navigation satellite system,GNSS)记录监测地震可有效弥补传统地震仪近场观测量程饱和、基线偏移等问题。相比于GNSS精密单点定位(precise point positioning,PPP),历元间差分测速方法可避免PPP收敛时间较长、需要外部改正数的问题,且测速方法获取的地震波形具有更高的信噪比。以2021年5月21日青海玛多MS 7.4地震为研究对象,提出利用载波相位历元间差分方法对该地区1 Hz高频GNSS数据进行处理,得到测站速度波形,并确定出玛多地震的震中位置、震级和发震时刻等参数。与中国地震局公布的结果比较,震中位置平均值相差约2.07 km;震级平均值相差约0.06个震级单位;发震时刻平均值相差4 s。结果表明,高频GNSS历元间差分测速方法反演地震三要素具有非常好的准确性与实用性。

关键词：高频GNSS 地震要素载波相位历元间差分峰值地面速度

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基于受激布里渊散射的二倍频光电振荡器

重庆邮电大学学报（自然科学版） 2024年第1期36卷 159-165页

作者：娄宏博王天枢李德琦张景凯孙畅郑佳伟陈严长春理工大学电子信息工程学院长春130022 长春理工大学空间光电技术国家与地方联合工程研究中心长春130022 长春理工大学光电工程学院长春130022

为了打破器件带宽限制,提高光电振荡器(optoelectronic oscillator, OEO)的频率范围,设计了一种基于受激布里渊散射的二倍频光电振荡器。系统并联了相位调制器(phase modulator, PM)和双平行马赫曾德尔调制器(dual parallel Mach Zender... 详细信息

为了打破器件带宽限制,提高光电振荡器(optoelectronic oscillator, OEO)的频率范围,设计了一种基于受激布里渊散射的二倍频光电振荡器。系统并联了相位调制器(phase modulator, PM)和双平行马赫曾德尔调制器(dual parallel Mach Zender modulator, DP-MZM),利用受激布里渊散射效应(stimulated Brillouin scattering,SBS)实现相位调制器的相位转幅度调制;打破±1阶边带平衡,利用光电探测器(photodetector, PD)拍频得到基频10 GHz信号;驱动DP-MZM,使其工作在最小传输点,实现载波抑制双边带调制(double side band with suppressed carrier, DSB-SC)产生二倍频20 GHz信号。实验结果显示,所设计的振荡器在OEO环路中基频信号为10 GHz的情况下,产生了20 GHz的二倍频信号,通过分析其边模抑制比性能、频率功率稳定性及相位噪声对系统性能进行验证。

关键词：光电振荡器(OEO) 受激布里渊散射效应(SBS) 相位调制器(PM) 双平行马赫曾德尔调制器(DP-MZM)

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In vivo antioxidant activity of rabbiteye blueberry(Vaccinium ashei cv.'Brightwell')anthocyanin extracts

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2023年第7期24卷 602-616页

作者： Jing WANG Xingyu ZHAO jiawei zheng Daniela D.HERRERA-BALANDRANO Xiaoxiao ZHANG Wuyang HUANG Zhongquan SUI College of Chemical Engineering Nanjing Forestry UniversityNanjing 210037China Institute of Agro-Product Processing Jiangsu Academy of Agricultural SciencesNanjing 210014China School of Food and Biological Engineering Jiangsu UniversityZhenjiang 212013China School of Life Sciences Nantong UniversityNantong 226007China Department of Food Science&Engineering School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghai 200240China

Blueberries are rich in phenolic compounds including anthocyanins which are closely related to biological health *** purpose of this study was to investigate the antioxidant activity of blueberry anthocyanins extracted from'Brightwell'rabbiteye blueberries in *** one week of adaptation,C57BL/6J healthy male mice were divided into different groups that were administered with 100,400,or 800 mg/kg blueberry anthocyanin extract(BAE),and sacrificed at different time points(0.1,0.5,1,2,4,8,or 12 h).The plasma,eyeball,intestine,liver,and adipose tissues were collected to compare their antioxidant activity,including total antioxidant capacity(T-AOC),superoxide dismutase(SOD)activity and glutathione-peroxidase(GSH-PX/GPX)content,and the oxidative stress marker malondialdehyde(MDA)*** results showed that blueberry anthocyanins had positive concentration-dependent antioxidant activity in *** greater the concentration of BAE,the higher the T-AOC value,but the lower the MDA *** enzyme activity of SOD,the content of GSH-PX,and messenger RNA(mRNA)levels of Cu,Zn-SOD,Mn-SOD,and GPX all confirmed that BAE played an antioxidant role after digestion in mice by improving their antioxidant *** in vivo antioxidant activity of BAE indicated that blueberry anthocyanins could be developed into functional foods or nutraceuticals with the aim of preventing or treating oxidative stress-related diseases.

关键词： Blueberry anthocyanin In vivo antioxidant activity Superoxide dismutase(SOD) Glutathione-peroxidase(GSH-PX/GPX) Malondialdehyde(MDA)

Addressing chemoresistance with a lipid gemcitabine nanotherapeutic strategy for effective treatment of pancreatic cancer

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Nano Research 2024年第9期17卷 8377-8388页

作者： jiawei Hong Shiyun Xian Shusen zheng Hangxiang Wang Donghai Jiang The First Affiliated Hospital NHC Key Laboratory of Combined Multi-Organ TransplantationCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesState Key Laboratory for Diagnosis and Treatment of Infectious DiseasesSchool of MedicineZhejiang UniversityHangzhou 310003China Jinan Microecological Biomedicine Shandong Laboratory Jinan 250117China

Resistance to gemcitabine in pancreatic cancer poses a significant clinical *** investigation is warranted to assess whether nano-formulation strategy can be employed to enhance the sensitivity of resistant strains to gemcitabine *** this study,using gemcitabine-resistant pancreatic cancer cell lines,we examined the therapeutic potential of a gemcitabine nanodelivery platform and assessed the ability to overcome drug resistance against resistant *** of human equilibrative nucleoside transporter 1(hENT1)led to reduced cellular uptake of gemcitabine,resulting in chemoresistance in pancreatic *** nanoparticles circumvented the entry blockade caused by hENT1 silencing through *** entry via clathrin-mediated endocytosis increased intracellular gemcitabine accumulation in gemcitabine-resistant pancreatic cancer ***,gemcitabine nanoparticles are preferential in vivo delivery to tumor tissues,likely due to the enhanced permeability and retention *** comparison to free gemcitabine,gemcitabine nanoparticles demonstrate a more pronounced cytotoxic effect on gemcitabine-resistant pancreatic cancer cells,with favorable *** study improved the efficacy of gemcitabine through nanotechnology,providing a novel strategy to address gemcitabine-resistant pancreatic cancer.

关键词： pancreatic cancer gemcitabine resistance gemcitabine nanoparticle human equilibrative nucleoside transporter 1

ITGA2B基因复合杂合突变所致遗传性血小板无力症家系分析及致病机制研究

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中华血液学杂志 2024年第4期45卷 370-377页

作者：卢晓梅付栋彦张耀方赵丽东王蕾杨嘉刘杰郑嘉伟杨林花王刚山西医科大学第二临床医学院(第二医院)血液科、山西医科大学血液病学研究所太原030001

目的对一个ITGA2B基因复合杂合突变导致的遗传性血小板无力症家系进行表型及基因型研究,并探索其分子致病机制。方法使用二磷酸腺苷、胶原、肾上腺素、花生四烯酸及瑞斯托霉素等诱聚剂进行血小板聚集试验,检测先证者及家系成员的血小板... 详细信息

目的对一个ITGA2B基因复合杂合突变导致的遗传性血小板无力症家系进行表型及基因型研究,并探索其分子致病机制。方法使用二磷酸腺苷、胶原、肾上腺素、花生四烯酸及瑞斯托霉素等诱聚剂进行血小板聚集试验,检测先证者及家系成员的血小板聚集率。通过流式细胞术检测血小板表面CD41(αⅡb)、CD61(β3)、CD42b(GPⅠb)的表达。采用基因测序技术进行基因鉴定。利用RT-PCR检测ITGA2B基因mRNA剪接情况,qRT-PCR检测ITGA2B基因mRNA相对水平。生物信息学分析评估突变位点的致病性及对蛋白结构和功能的影响。通过Western blot检测分析血小板总αⅡb、β3的表达。结果除瑞斯托霉素外其他4种诱聚剂均无法使先证者血小板聚集。流式细胞术检测先证者血小板表面αⅡb的表达仅为0.25%,β3弱表达为9.76%,而GPⅠb表达相对正常,其余家系成员膜糖蛋白表达基本正常。基因测序结果显示先证者存在ITGA2B基因c.480C>G与c.2929C>T复合杂合突变,其中c.480C>G突变遗传自其母亲,c.2929C>T遗传自其父亲。RT-PCR及测序结果表明c.480C>G突变导致先证者及其母亲发生c.476G-574A(p.S160-S192)共99个碱基缺失的mRNA剪接。qRT-PCR检测发现c.2929C>T突变导致先证者及其父亲ITGA2B基因mRNA水平减低。生物信息学分析提示c.480C>G突变形成了与hnRNP A1蛋白结合序列,产生了5'SS剪接位点。αⅡb亚基的蛋白三维结构模型显示,p.S160-S192缺失的β-propeller结构域第2 blade缺失两条β链和一个α螺旋;c.2929C>T无义突变使得翻译提前终止产生p.R977-E1039缺失的截短型蛋白,包括胞质域(CD)、跨膜域(TM)以及胞外Calf-2结构域一条β链的缺失。Western blot检测先证者血小板总αⅡb表达缺失、β3的相对表达量为正常人的11.36%。结论ITGA2B基因第4外显子c.480C>G与第28外显子c.2929C>T的复合杂合突变是本家系遗传性血小板无力症的致病原因。

关键词：遗传性血小板无力症 ITGA2B基因整合素αⅡbβ3 mRNA剪接无义突变

7075铝合金表面钼/钛/钒复合转化膜的制备与性能表征

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电镀与精饰 2024年第4期46卷 90-98页

作者：罗有斌刘宁华郑嘉伟祝闻赖心翘赖洪刘明杰广州三孚新材料科技股份有限公司广东广州510700 东莞理工学院材料科学与工程学院广东东莞523808

采用钼酸盐和钛酸盐为主盐,以偏钒酸钠为成膜促进剂,植酸钠为有机添加剂,在7075铝合金表面制备了钼/钛/钒复合转化膜。借助扫描电子显微镜(SEM)、能谱仪(EDS)和X射线光电子能谱仪(XPS)分析了膜层的微观形貌、元素组成和化学成分,采用电... 详细信息

采用钼酸盐和钛酸盐为主盐,以偏钒酸钠为成膜促进剂,植酸钠为有机添加剂,在7075铝合金表面制备了钼/钛/钒复合转化膜。借助扫描电子显微镜(SEM)、能谱仪(EDS)和X射线光电子能谱仪(XPS)分析了膜层的微观形貌、元素组成和化学成分,采用电化学工作站考察了基体和膜层的耐蚀性。实验结果表明:最佳转化液配方为2 g·L^(-1)植酸钠、1.5 g·L^(-1)偏钒酸钠、1.5 g·L^(-1)六氟钛酸及25 g·L^(-1)钼酸铵,最佳成膜条件为15 min和35℃。膜层主要成分为Al_(2)O_(3)、MoO_(2)、MoO_(3)、V_(2)O_(5)和TiO_(2)。钼/钛/钒复合转化膜使7075铝合金的腐蚀电位正移了206.401 mV,腐蚀电流密度降低了9.912μA·cm^(-2),有效提高了基体的耐蚀性。

关键词： 7075铝合金钼/钛/钒复合转化膜耐腐蚀钼酸铵无铬

Enzymatic preparation of mono-and diacylglycerols:A review

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Grain & Oil Science and Technology 2023年第4期6卷 185-205页

作者： jiawei zheng Yudong Liang Jiaxi Li Shuping Lin Qiangyue Zhang Kanghua Zuo Nanjing Zhong Xuebing Xu School of Food Science Guangdong Pharmaceutical UniversityZhongshan 528458China College of Food Science and Technology Henan University of TechnologyZhengzhou 450001China Wilmar(Shanghai)Biotechnology Research and Development Center Ltd. Pudong New DistrictShanghai 200137China

Monoacylglycerols(MAGs) and diacylglycerols(DAGs) are partial glycerides widely used in food industry. They are safe and non-toxic food emulsifiers, especially for MAGs. MAGs account for approximately 75% of the total emulsifiers in food industry worldwide. DAGs are recognized as functional cooking oils, they can suppress body fat accumulation and postprandial serum triacylglycerols(TAGs) level. The traditional production of MAGs and DAGs is based on the chemical method, which requires high reaction temperature usually up to 200–260 ℃. Such high temperature is not suitable for oil containing heat sensitive polyunsaturated fatty acids. Enzymatic approach has been received increasing attentions. Enzymatic production of partial glycerides to replace chemical processes has been in industry, particularly for DAGs production as the products have been claimed as a functional and nutritional oil. Enzyme technology for the processing of oils and fats has been moved to industry step by step and case by case during the last 20 years. More and more applications are particularly moving into bulky oils and fats processing. At the same time, the cost of enzymes as a commercial product is reducing steadily. This review summarized the recent 15 years advances on the the enzymatic preparation of MAGs and DAGs. The critical process parameters under different reaction routes were presented and emphasized. The reaction media not only increased the homogeneity of the reaction system, but also shifted the reaction equilibrium towards the target product generation, and this part was stated in detail. In addition, the patent evaluation was included, and the application of MAGs and DAGs was covered.

关键词： Monoacylglycerol Diacylglycerol Enzymatic production Esterification Glycerolysis Tert-butanol Ionic liquids Patent evaluation