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硬膜外扩容技术对剖宫产腰麻罗哌卡因ED50及母婴安全性的影响
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作者 潘轶瑜 潘郑斌 陈皆锋 《浙江创伤外科》 2025年第10期1882-1885,共4页
目的 探讨剖宫产腰麻时使用15 mL生理盐水进行硬膜外扩容对母婴安全性和罗哌卡因半数有效剂量(median effective dose,ED50)的影响。方法 选取2022年3月至2023年12月在浙江省绍兴市妇幼保健院行剖宫产的60例足月单胎初产妇,随机分为研... 目的 探讨剖宫产腰麻时使用15 mL生理盐水进行硬膜外扩容对母婴安全性和罗哌卡因半数有效剂量(median effective dose,ED50)的影响。方法 选取2022年3月至2023年12月在浙江省绍兴市妇幼保健院行剖宫产的60例足月单胎初产妇,随机分为研究组和对照组各30例。研究组腰麻完成后给予硬膜外生理盐水15 mL,对照组则仅行腰麻。比较两组麻醉效果、母婴结局指标及罗哌卡因ED50值。结果 两组产妇麻醉效果、产妇不良反应发生情况及新生儿Apgar评分上差异无统计学意义(P>0.05)。研究组罗哌卡因ED50为9.450mg(95%CI:8.660~10.226),显著低于对照组12.809 mg(95%CI:11.897~13.889),差异有统计学意义(P<0.05)。在运动神经阻滞起效和感觉神经阻滞持续时间上,两组产妇差异无统计学意义(P>0.05)。研究组感觉神经阻滞起效较对照组快,差异有统计学意义(P<0.05)。运动神经阻滞持续时间较对照组短,差异有统计学意义(P<0.05)。结论 剖宫产腰麻时使用15 mL生理盐水硬膜外扩容,能够显著降低罗哌卡因ED50水平,缩短起效时间,对母婴结局未产生不良影响。 展开更多
关键词 罗哌卡因 剖宫产术 腰麻 硬膜外容量扩张 ed50
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刚结婚就ED,这是怎么了
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作者 刘闽军 陈圣福 《家庭药师》 2025年第3期139-139,共1页
据调查,80%新婚夫妇有初次性挫折,称之为“新婚性ED”。这也是婚后第一年离婚最常见的原因之一。新婚之夜的败仗经过3年爱情长跑,明宁、月儿终于喜结良缘。结婚之前两人都没有性经验,他们共同的心愿是,要把那一刻留到新婚之时。不料,洞... 据调查,80%新婚夫妇有初次性挫折,称之为“新婚性ED”。这也是婚后第一年离婚最常见的原因之一。新婚之夜的败仗经过3年爱情长跑,明宁、月儿终于喜结良缘。结婚之前两人都没有性经验,他们共同的心愿是,要把那一刻留到新婚之时。不料,洞房花烛夜,每每正要进入主题时,明宁就萎靡不振了。尽管月儿并没有责怪他,但他却觉得很没面子。 展开更多
关键词 新婚性ed 初次性挫折 洞房花烛夜 婚后离婚
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基于ED的港口物流系统实验教学分析
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作者 李秀华 《物流科技》 2025年第17期165-166,177,共3页
近年来,跨境电商的蓬勃发展带动国际物流业务快速发展,进而需要处理的港口物流业务量逐渐增多,但是目前处理港口物流业务的服务端口数量有限,已不能满足正常进出口业务的需求,为了提高港口物流进出口作业服务效率,通过ED软件模拟仿真,... 近年来,跨境电商的蓬勃发展带动国际物流业务快速发展,进而需要处理的港口物流业务量逐渐增多,但是目前处理港口物流业务的服务端口数量有限,已不能满足正常进出口业务的需求,为了提高港口物流进出口作业服务效率,通过ED软件模拟仿真,分析探究港口物流业务服务端口的数量以及服务时间是否满足需求,从而对港口物流系统作业进行优化。 展开更多
关键词 跨境电商 ed 物流系统优化
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遭遇ED,莫急着“壮阳”
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作者 李秋艳 《家庭药师》 2025年第7期61-61,共1页
在男科疾病中,勃起功能障碍(简称ED)占很大的比例。购买所谓壮阳保健品的,也主要是认为自己有ED的人。然而,很多人不知道,在勃起功能障碍的背后,往往隐藏着其他疾病,如高血压、高血脂、糖尿病、冠心病等。如果一味“壮阳”,罔顾其他,后... 在男科疾病中,勃起功能障碍(简称ED)占很大的比例。购买所谓壮阳保健品的,也主要是认为自己有ED的人。然而,很多人不知道,在勃起功能障碍的背后,往往隐藏着其他疾病,如高血压、高血脂、糖尿病、冠心病等。如果一味“壮阳”,罔顾其他,后果可能很严重。 展开更多
关键词 勃起功能障碍 高血压 壮阳保健品 ed
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Distributed Economic Dispatch Algorithms of Microgrids Integrating Grid-Connected and Isolated Modes
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作者 Zhongxin Liu Yanmeng Zhang +1 位作者 Yalin Zhang Fuyong Wang 《IEEE/CAA Journal of Automatica Sinica》 2025年第1期86-98,共13页
The economic dispatch problem(EDP) of microgrids operating in both grid-connected and isolated modes within an energy internet framework is addressed in this paper. The multi-agent leader-following consensus algorithm... The economic dispatch problem(EDP) of microgrids operating in both grid-connected and isolated modes within an energy internet framework is addressed in this paper. The multi-agent leader-following consensus algorithm is employed to address the EDP of microgrids in grid-connected mode, while the push-pull algorithm with a fixed step size is introduced for the isolated mode. The proposed algorithm of isolated mode is proven to converge to the optimum when the interaction digraph of microgrids is strongly connected. A unified algorithmic framework is proposed to handle the two modes of operation of microgrids simultaneously, enabling our algorithm to achieve optimal power allocation and maintain the balance between power supply and demand in any mode and any mode switching. Due to the push-pull structure of the algorithm and the use of fixed step size,the proposed algorithm can better handle the case of unbalanced graphs, and the convergence speed is improved. It is documented that when the transmission topology is strongly connected and there is bi-directional communication between the energy router and its neighbors, the proposed algorithm in composite mode achieves economic dispatch even with arbitrary mode switching.Finally, we demonstrate the effectiveness and superiority of our algorithm through numerical simulations. 展开更多
关键词 Consensus algorithm distributed optimization economic dispatch(ed) energy router(ER) multi-agent systems
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国产变速的加速之路——轮峰EDS TT7110书写电子变速新篇章
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作者 奇思 《中国自行车》 2025年第6期94-97,共4页
当中国自行车产业全面开启高端化转型,每一个技术创新都在重新定义行业格局。轮峰EDS TT7110的诞生之路,是一条典型的国产加速之路:2015年布局高端研发,2022年推出首款山地车电子变速系统,2025年TT套件正式问世--轮峰用10年技术积累打... 当中国自行车产业全面开启高端化转型,每一个技术创新都在重新定义行业格局。轮峰EDS TT7110的诞生之路,是一条典型的国产加速之路:2015年布局高端研发,2022年推出首款山地车电子变速系统,2025年TT套件正式问世--轮峰用10年技术积累打破国际垄断。这条加速之路的背后是轮峰与多所高等院校的深度产学研合作,是120余项专利技术的坚实支撑,更是从替代进口到出口全球、从学习追赶到创新引领的完整跃迁。 展开更多
关键词 轮峰edS TT7110 国产变速 电子变速
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Mean 24-hour end-tidal carbon dioxide following diagnosis predicts mortality in patients with sepsis
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作者 Jingyi Wang Li Weng +1 位作者 Jun Xu Bin Du 《World Journal of Emergency Medicine》 2025年第4期383-386,共4页
Sepsis management has significantly improved over the past decades,with intensivists playing a pivotal role in its identification and treatment.[1,2]However,resource constraints in large tertiary hospitals in China li... Sepsis management has significantly improved over the past decades,with intensivists playing a pivotal role in its identification and treatment.[1,2]However,resource constraints in large tertiary hospitals in China limit patient admissions,leading to overcrowding in the emergency departments(EDs)with critically ill patients.[3]This highlights the urgent need for enhanced risk stratification and optimized sepsis management in emergency settings. 展开更多
关键词 enhanced risk stratification hour end tidal carbon dioxide emergency departments eds intensivists SEPSIS MORTALITY sepsis management resource constraints
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基于ED模型的点火能量对中心分级燃烧室火焰发展影响的数值研究
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作者 许鹏宇 王成军 +2 位作者 陶海一 乔征宇 于建桥 《燃气涡轮试验与研究》 2025年第1期115-122,共8页
以发动机单头部中心分级燃烧室点火过程为研究对象,基于能量沉积(ED)模型,利用用户自定义函数(UDF),模拟了不同点火能量工况下的单脉冲火花塞放电过程;研究了点火能量对中心分级燃烧室点火过程的影响;探究了中心分级燃烧室设计工况下的... 以发动机单头部中心分级燃烧室点火过程为研究对象,基于能量沉积(ED)模型,利用用户自定义函数(UDF),模拟了不同点火能量工况下的单脉冲火花塞放电过程;研究了点火能量对中心分级燃烧室点火过程的影响;探究了中心分级燃烧室设计工况下的最小点火能量。结果表明:能够成功点火的工况,其火焰发展路径和趋势基本一致,增大点火能量并未影响火焰传播路径,仅会缩短燃烧室点火后初始火核发展为稳定火焰的时间;形成初始火核的能量能够传递至逆流区并形成稳定的火焰核心,是成功点火的必要条件;当以最小点火能量进行点火时,即使能够成功点燃燃烧室,但火焰传播存在耗时长、传播极其不稳定等现象。 展开更多
关键词 ed模型 中心分级燃烧室 点火能量 初始火核 火焰传播 航空发动机
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Holder’s inequalities for a class of analytic functions connected with a certain hybrid-type convolution operator
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作者 H.M.Srivastava Sheza M.El-Deeb 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第2期443-457,共15页
By using a certain hybrid-type convolution operator,we first introduce a new subclass of normalized analytic functions in the open unit disk.For members of this analytic function class,we then derive several propertie... By using a certain hybrid-type convolution operator,we first introduce a new subclass of normalized analytic functions in the open unit disk.For members of this analytic function class,we then derive several properties and characteristics including(for example)the modified Hadamard products,Holder's inequalities and convolution properties as well as some closure properties under a general family of integral transforms. 展开更多
关键词 analytic functions univalent functions binomial series:hybrid-type convolution operator Holder's inequalities modi ed Hadamard product convolution properties closure properties under integral transforms
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中国性学会携手晖致医药等发布“ED全周期健康管理”大众宝典
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作者 《中国性科学》 2025年第11期F0002-F0002,共1页
2025年10月28日第26个“中国男性健康日”到来之际,为推动男性健康融入全民健康、践行“男性健康主动管理幸福生活共同守护”的宣传主题,“硬核实力·守护全程”勃起功能障碍(ED)全周期健康管理科普活动成功在京举办。
关键词 中国男性健康日 ed全周期健康管理
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降压药能与抗ED药物同服吗
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作者 毕瑞 《漫科学(新健康)》 2024年第1期30-31,共2页
高血压作为一种最常见的心血管疾病,与勃起功能障碍(ED)有着密切的联系。根据美国马萨诸塞州男性老年化研究资料显示,在40~70岁男性当中有超过一半的人受到不同程度ED的困扰,年发病率为124/1000。同时据流行病学研究发现,ED在非高血压... 高血压作为一种最常见的心血管疾病,与勃起功能障碍(ED)有着密切的联系。根据美国马萨诸塞州男性老年化研究资料显示,在40~70岁男性当中有超过一半的人受到不同程度ED的困扰,年发病率为124/1000。同时据流行病学研究发现,ED在非高血压人群中发生率为16%;在高血压人群中,发病率则高达32.1%,远高于正常血压人群。那为什么高血压容易并发ED呢?原因主要有以下3点。 展开更多
关键词 正常血压 流行病学研究 高血压人群 老年化 心血管疾病 美国马萨诸塞州 降压药 ed
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System View在EDA实验中的应用 被引量:1
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作者 张健 黄光明 《鄂州大学学报》 2001年第4期14-17,共4页
在电子线路和通信课程的实验教学中,往往因为条件的限制而无法开设许多实验,本文推荐System View作为实验教学软件,它有强大的动态系统的模拟仿真功能,并适用于滤波器设计、信号处理、完整通信系统的设计与仿真等实验,... 在电子线路和通信课程的实验教学中,往往因为条件的限制而无法开设许多实验,本文推荐System View作为实验教学软件,它有强大的动态系统的模拟仿真功能,并适用于滤波器设计、信号处理、完整通信系统的设计与仿真等实验,可以构建一个良好的实验教学平台。 展开更多
关键词 systemVIEW edA 实验 教学
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Evaluation of modifi ed Alvarado scoring system and RIPASA scoring system as diagnostic tools of acute appendicitis 被引量:14
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作者 Abdullah Shuaib Ali Shuaib +3 位作者 Zainab Fakhra Bader Marafi Khalid Alsharaf Abdullah Behbehani 《World Journal of Emergency Medicine》 CAS 2017年第4期276-280,共5页
BACKGROUND: Acute appendicitis is the most common surgical condition presented in emergency departments worldwide. Clinical scoring systems, such as the Alvarado and modified Alvarado scoring systems, were developed w... BACKGROUND: Acute appendicitis is the most common surgical condition presented in emergency departments worldwide. Clinical scoring systems, such as the Alvarado and modified Alvarado scoring systems, were developed with the goal of reducing the negative appendectomy rate to 5%–10%. The Raja Isteri Pengiran Anak Saleha Appendicitis(RIPASA) scoring system was established in 2008 specif ically for Asian populations. The aim of this study was to compare the modif ied Alvarado with the RIPASA scoring system in Kuwait population.METHODS: This study included 180 patients who underwent appendectomies and were documented as having "acute appendicitis" or "abdominal pain" in the operating theatre logbook(unit B) from November 2014 to March 2016. The sensitivity, specificity, positive predictive value(PPV), negative predictive value(NPV), diagnostic accuracy, predicted negative appendectomy and receiver operating characteristic(ROC) curve of the modified Alvarado and RIPASA scoring systems were derived using SPSS statistical software.RESULTS: A total of 136 patients were included in this study according to our criteria. The cut-off threshold point of the modif ied Alvarado score was set at 7.0, which yielded a sensitivity of 82.8% and a specif icity of 56%. The PPV was 89.3% and the NPV was 42.4%. The cut-off threshold point of the RIPASA score was set at 7.5, which yielded a 94.5% sensitivity and an 88% specif icity. The PPV was 97.2% and the NPV was 78.5%. The predicted negative appendectomy rates were 10.7% and 2.2% for the modif ied Alvarado and RIPASA scoring systems, respectively. The negative appendectomy rate decreased significantly, from 18.4% to 10.7% for the modified Alvarado, and to 2.2% for the RIPASA scoring system, which was a signif icant difference(P<0.001) for both scoring systems.CONCLUSION: Based on the results of this study, the RIPASA score is a simple scoring system with better sensitivity and specif icity than the modif ied Alvarado scoring system in Asian populations. It consists of 14 clinical parameters that can be obtained from a good patient history, clinical examination and laboratory investigations. The RIPASA scoring system is more accurate and specific than the modif ied Alvarado scoring system for Kuwait population. 展开更多
关键词 ACUTE APPENDICITIS Modifi ed Alvarado SCORE RIPASA SCORE
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基于Edge Drawing的工业图像圆检测算法 被引量:1
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作者 杨庆五 罗小辉 刘鑫 《计算机与现代化》 2024年第11期121-126,共6页
针对基于Hough变换类圆检测算法所需的参数较多和计算量较大的问题,本文提出一种实时的、无参数的圆检测算法。该算法通过利用ED(Edge Drawing)算法得到图像中的若干边缘片段,并通过线段检测器从边缘片段几何中提取可能构成圆的圆弧线... 针对基于Hough变换类圆检测算法所需的参数较多和计算量较大的问题,本文提出一种实时的、无参数的圆检测算法。该算法通过利用ED(Edge Drawing)算法得到图像中的若干边缘片段,并通过线段检测器从边缘片段几何中提取可能构成圆的圆弧线段集合。对每一对线段进行分析,判断是否可以形成一对有效线段,从而生成初始的圆集合。接下来依据圆边缘的几何属性生成候选圆并采用反向验证原理进行验证。实验结果表明,该方法在图像中的圆存在模糊、阴影和遮挡等干扰下仍有较好的检测效果,并且相较于其他算法,在工业图像上的精度和稳定性得到显著提高。 展开更多
关键词 圆检测 极性分析 ed 圆拟合 区域约束
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Systematic mutational analysis of epitope-grafted ED3 immunogenicity reveals a DENV3-DENV4 bi-serospecific ED3 mutant 被引量:1
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作者 Mamtaz Sultana Nazmul Hasan +1 位作者 Mamunur R.Mahib Mohammad M.Islam 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2022年第2期63-70,I0001-I0004,共12页
Objective:To identify the residue determinants of the serospecificity and sero-cross-reactivity of dengue virus(DENV)envelope protein domain 3(ED3),which contains two major putative epitopes of DENV.Methods:We constru... Objective:To identify the residue determinants of the serospecificity and sero-cross-reactivity of dengue virus(DENV)envelope protein domain 3(ED3),which contains two major putative epitopes of DENV.Methods:We constructed ED3 from DENV3(3ED3)and DENV4(4ED3),and six epitope-grafted variants,where we transferred epitope 1(L304I,K305D,V309M,and S310A)and/or epitope 2(D383N,K384S,K387T,and N389H)of 4ED3 onto 3ED3 and vice-versa.Swiss albino mice aged 3-4 weeks were immunized against wildtype and epitope-grafted ED3 variants and anti-ED3 IgG antibody responses were determined using ELISA.Results:Mouse immunization using 3ED3 and 4ED3 generated serotype-specific antisera,as expected.Similarly,most epitope-grafted ED3s produced antisera serospecific to the template ED3 with little or no cross-recognition of ED3 of the serotype from which the epitopes were taken.These indicated that a mere grafting of the epitope was not sufficient to transfer serospecificity,contrary to our expectations.However,one epitope-grafted ED3 mutant,where epitope 1 of 3ED3 was grafted onto 4ED3(4ED3^(epi1)),generated antisera that was serospecific to both 4ED3 and 3ED3.Conclusions:The 4ED3^(epi1)is a chimeric ED3 that produces antisera possessing serospecificity to both 3ED3 and 4ED3 onto a common 4ED3 scaffold.The 4ED3^(epi1),therefore,provides a unique tool for analyzing serospecificity and sero-cross-reactivity in dengue.We believe that chimeric ED3 may provide a template for future recombinant ED3 possessing serospecificity of multiple DENVs onto a single scaffold and may pave a way developing tri-and/or tetravalent anti-DENV antisera. 展开更多
关键词 Dengue virus serospecificity Sero-cross-recognition Anti-ed3 antibodies Epitope-grafting Chimeric ed3
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Spectra of seismic force reduction factors of MDOF systems normalized by two characteristic periods 被引量:1
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作者 Li Xiao Tong Genshu Zhang Lei 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2020年第1期53-69,共17页
Seismic force reduction factor(SFRF) spectra of shear-type multi-degree-of-freedom(MDOF) structures are investigated. The modified Clough model, capable of considering the strength-degradation/hardening and stiffnessd... Seismic force reduction factor(SFRF) spectra of shear-type multi-degree-of-freedom(MDOF) structures are investigated. The modified Clough model, capable of considering the strength-degradation/hardening and stiffnessdegradation, is adopted. The SFRF mean spectra using 102 earthquake records on a typical site soil type(type C) are constructed with the period abscissa being divided into three period ranges to maintain the peak features at the two sitespecific characteristic periods. Based on a large number of results, it is found that the peak value of SFRF spectra may also exist for MDOF, induced by large high-mode contributions to elastic base shear, besides the mentioned two peak values. The variations of the stiffness ratio λk and the strength ratio λF of the top to bottom story are both considered. It is found that the SFRFs for λF ≤λk are smaller than those for λF > λk. A SFRF modification factor for MDOF systems is proposed with respect to SDOF. It is found that this factor is significantly affected by the story number and ductility. With a specific λF(= λk0.75), SFRF mean spectra are constructed and simple solutions are presented for MDOF systems. For frames satisfying the strong column/weak beam requirement, an approximate treatment in the MDOF shear-beam model is to assign a post-limit stiffness 15%-35% of the initial stiffness to the hysteretic curve. SFRF spectra for MDOF systems with 0.2 and 0.3 times the post-limit stiffness are remarkably larger than those without post-limit stiffness. Thus, the findings that frames with beam hinges have smaller ductility demand are explained through the large post-limit stiffness. 展开更多
关键词 seismic force reduction factor multi-degree of freedom modifi ed Clough model characteristic period highmode eff ect post-limit stiff ness analysis
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Analysis and Design of Wireless Networked Control System Utilizing Adaptive Coded ModulationAnalysis and Design of Wireless Networked Control System Utilizing Adaptive Coded Modulation 被引量:4
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作者 YANG Li GUAN Xin-Ping LONG Cheng-Nian LUO Xiao-Yuan 《自动化学报》 EI CSCD 北大核心 2009年第7期911-918,共8页
关键词 无线网络控制系统 计算机技术 自动化系统 网络条件
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A dual-RPA based lateral flow strip for sensitive,on-site detection of CP4-EPSPS and Cry1Ab/Ac genes in genetically modified crops 被引量:2
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作者 Jinbin Wang Yu Wang +7 位作者 Xiuwen Hu Yifan Chen Wei Jiang Xiaofeng Liu Juan Liu Lemei Zhu Haijuan Zeng Hua Liu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期183-190,共8页
Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSP... Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSPS and Cry1Ab/Ac was proposed and combined with a lateral flow immunochromatographic assay,named“Dual-RPA-LFD”,to visualize the dual detection of genetically modified(GM)crops.In which,the herbicide tolerance gene CP4-EPSPS and the insect resistance gene Cry1Ab/Ac were selected as targets taking into account the current status of the most widespread application of insect resistance and herbicide tolerance traits and their stacked traits.Gradient diluted plasmids,transgenic standards,and actual samples were used as templates to conduct sensitivity,specificity,and practicality assays,respectively.The constructed method achieved the visual detection of plasmid at levels as low as 100 copies,demonstrating its high sensitivity.In addition,good applicability to transgenic samples was observed,with no cross-interference between two test lines and no influence from other genes.In conclusion,this strategy achieved the expected purpose of simultaneous detection of the two popular targets in GM crops within 20 min at 37°C in a rapid,equipmentfree field manner,providing a new alternative for rapid screening for transgenic assays in the field. 展开更多
关键词 Genetically modifi ed crops On-site detection Lateral fl ow test strips Dual recombinase polymerase amplification (RPA)
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Outstanding proton conductivity over wide temperature and humidity ranges and enhanced mechanical, thermal stabilities for surface-modified MIL-101-Cr-NH_(2)/Nafion composite membranes 被引量:1
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作者 Xu Li Dongwei Zhang +7 位作者 Si Chen Yingzhao Geng Yong Liu Libing Qian Xi Chen Jingjing Li Pengfei Fang Chunqing He 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第11期1734-1746,共13页
High-performance proton exchange membranes are of great importance for fuel cells.Here,we have synthesized polycarboxylate plasticizer modified MIL-101-Cr-NH_(2)(PCP-MCN),a kind of hybrid metal-organic framework,which ... High-performance proton exchange membranes are of great importance for fuel cells.Here,we have synthesized polycarboxylate plasticizer modified MIL-101-Cr-NH_(2)(PCP-MCN),a kind of hybrid metal-organic framework,which exhibits a superior proton conductivity.PCP-MCN nanoparticles are used as additives to fabricate PCP-MCN/Nafion composite membranes.Microstructures and characteristics of PCP-MCN and these membranes have been extensively investigated.Significant enhancement in proton conduction for PCP-MCN around 55℃ is interestingly found due to the thermal motion of the PCP molecular chains.Robust mechanical properties and higher thermal decomposition temperature of the composite membranes are directly ascribed to strong intermolecular interactions between PCP-MCN and Nafion side chains,i.e.,the formation of substantial acid–base pairs(-SO_(3)^(-)…^(+)H–NH-),which further improves compatibility between additive and Nafion matrix.At the same humidity and temperature condition,the water uptake of composite membranes significantly increases due to the incorporation of porous additives with abundant functional groups and thus less crystallinity degree in comparison to pristine Nafion.Proton conductivity(σ)over wide ranges of humidities(30-100%RH at 25℃)and temperatures(30-98℃ at 100%RH)for prepared membranes is measured.The s in PCPMCN/Nafion composite membranes is remarkably enhanced,i.e.0.245 S/cm for PCP-MCN-3wt.%/Nafion is twice that of Nafion membrane at 98℃ and 100%RH,because of the establishment of well-interconnected proton transport ionic water channels and perhaps faster protonation–deprotonation processes.The composite membranes possess weak humidity-dependence of proton transport and higher water uptake due to excellent water retention ability of PCP-MCN.In particular,when 3 wt.%PCP-MCN was added to Nafion,the power density of a single-cell fabricated with this composite membrane reaches impressively 0.480,1.098 W/cm^(2) under 40%RH,100%RH at 60℃,respectively,guaranteeing it to be a promising proton exchange membrane. 展开更多
关键词 Nafion composite membrane Surface-modified MIL-101-Cr-NH_(2) Proton conductivity Single-cell performance
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Novel Membranes Regenerated from Blends of Cellulose/Gluten Using Ethylenediamine/Potassium Thiocyanate Solvent System
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作者 Yang Yu Ramiz Boy Richard Kotek 《Journal of Renewable Materials》 SCIE 2019年第1期41-55,共15页
Current industrial methods for dissolution of cellulose in making regenerated cellulose products are relatively expensive,toxic and dangerous and have environmental problems coming with the hazard chemical wastes.To s... Current industrial methods for dissolution of cellulose in making regenerated cellulose products are relatively expensive,toxic and dangerous and have environmental problems coming with the hazard chemical wastes.To solve these problems,a novel ethylenediamine and potassium thiocyanate(ED/KSCN)solvent system was developed,that is economical,ecofriendly,and highly efficient.The ED/KSCN solvent system was proven to be a suitable solvent for fabricating cellulose(blended with other polymers)membranes.In this study,gluten was used to develop nonporous membranes with cellulose.The method of casting these membranes provided better ones than the former researchers’techniques.These composite membranes’physical and mechanical properties were studied by analysis of morphology,viscosity,crystallinity,thermal behaviors,tensile properties and water absorption of membranes.Results showed that membranes are nonporous,uniform,strong,flexible,ecofriendly and renewable.Mechanical and physical properties were influenced by the ratio of cellulose/gluten.By blending 40% gluten,the tensile strength of cellulose membrane dropped to 15.89 MPa from 35.11 MPa.However,its elongation at break increased from 35.3% to 57.02% accordingly. 展开更多
关键词 CELLULOSE GLUTEN blended film NOVEL ed/KSCN solvent physical and mechanical properties
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