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Chinese Chemical Letters 2010年第2期21卷 151-154页

作者： hu, yu feng Luo, Jun Lue, Chun Xu Nanjing Univ Sci & Technol Sch Chem Engn Nanjing 210094 Peoples R China

Anhydrous tetrabutylammonium fluoride(TBAF_(anh).) has been found to be a highly efficient fluorinating reagent for nucleophilic aromatic fluorinations such as fluorodenitration or halogen exchange(Halex) *** products were formed in high to excellent yields under surprisingly mild reaction conditions and no phenol or ether side-products were detected in these reactions.

关键词： TBAF_(anh). Fluoroaromatics Fluorodenitration Halex

Dek219 encodes the DICER-LIKE1 protein that affects chromatin accessibility and kernel development in maize

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Journal of Integrative Agriculture 2023年第10期22卷 2961-2980页

作者： XIE Si-di TIAN Ran ZHANG Jun-jie LIU Han-mei LI Yang-ping hu yu-feng yu Guo-wu huANG yu-bi LIU Ying-hong State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China Sichuan Agricultural UniversityChengdu 611130P.R.China College of Life Science Sichuan Agricultural UniversityYa’an 625014P.R.China College of Agronomy Sichuan Agricultural UniversityChengdu 611130P.R.China Maize Research Institute Sichuan Agricultural UniversityChengdu 611130P.R.China

Chromatin accessibility plays a vital role in gene transcriptional ***,the regulatory mechanism of chromatin accessibility,as well as its role in regulating crucial gene expression and kernel development in maize(Zea mays)are poorly *** this study,we isolated a maize kernel mutant designated as defective kernel219(dek219),which displays opaque endosperm and embryo ***219 encodes the DICER-LIKE1(DCL1)protein,an essential enzyme in mi RNA *** of function of Dek219 results in significant reductions in the expression levels of most mi RNAs and histone *** research showed that the Heat shock transcription factor17(Hsf17)-Zm00001d016571 module may be one of the factors affecting the expression of histone *** results for transposase-accessible chromatin sequencing(ATAC-seq)indicated that the chromatin accessibility of dek219 is altered compared with that of wild type(WT),which may regulate the expression of crucial genes in kernel *** analyzing differentially expressed genes(DEGs)and differentially accessible chromatin regions(ACRs)between WT and dek219,we identified 119 candidate genes that are regulated by chromatin accessibility,including some reported to be crucial genes for kernel *** together,these results suggest that Dek219 affects chromatin accessibility and the expression of crucial genes that are required for maize kernel development.

关键词： maize kernel development chromatin accessibility histone miRNA

Antidiabetic effect of a novel non-thiazolidinedione PPAR γ/α agonist on ob/ob mice

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Acta Pharmacologica Sinica 2006年第10期27卷 1346-1352页

作者： Xi hu Ying feng yu SHEN Xiao-feng ZHAO Juan-hong yu yu-she YANG Ying LENG~2 Shanghai Institute of Materia Medica,Shanghai Institute for Biological Sciences,Chinese Academy of Sciences,Shanghai 201203,China Shanghai Institute of Materia Medica Shanghai Institute for Biological Sciences Chinese Academy of Sciences Shanghai China

Aim:To study whether T33,a new synthesized non-thiazolidinedione(TZD)per-oxisome proliferator-activated receptor(PPAR)γ/α dual agonist has an antidia-betic effect on ob/ob ***:Ob/ob mice were treated with 4 mg/kg or 8mg/kg T33 by gavage for 20 *** glucose levels were measured *** glucose tolerance test(OGTT)and an insulin tolerance test(ITT)were pre-formed on d 8 and d 12,*** levels of insulin,triglyceride and freefatty acid(FFA)in the serum were measured at the end of *** and liver triglyceride content was also ***:T33reduced the hyperglycemia,hyperinsulinemia and hyperlipidemia of the ob/*** OGTT and ITT showed that the insulin resistance state of the ob/obmice was obviously ameliorated after T33 *** 20 d treatment with 8mg/kg T33,the triglyceride content in the gastrocnemius muscle decreasedsignificantly.T33 did not have any effect on triglyceride content in the liver,whereas rosiglitazone significantly increased the hepatocyte lipid ***:The PPARγ/α dual agonist T33 has antidiabetic and insulin-sensitiz-ing effects in ob/ob *** has the potential to be a new therapeutic candidate forthe treatment of type 2 diabetes.

关键词： diabetes insulin-sensitizing peroxisome proliferator-activated receptors thiazolidinediones

Isolation and differentiation of embryonic stem cells from BALB/c mouse

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Neuroscience Bulletin 2006年第1期22卷 7-13页

作者： Wei GONG Zhuo-Jing LUO hua HAN Hong-Yan QIN You-Biao Chu Xue-yu hu Li-feng LAN Department of Orthopaedics XiJing Hospital the Fourth Military University Xi＇an 710032 China

Objective To invest the efficient method which can culture and induce embryonic stem cells to neuroeyte in vitro. Methods Isolate the blastula o f 3.5 d from BALB/c species mouse. Culture the cells from inner cell mass （inner cell mass, ICM） which were isolated by mechanical method on the mouse embryonic fibroblaste cell （MEF） feeder layer or 0.1% gelatin coated dishes. The stem ceils were identified by characterized morphology, alkaline phosphatase stain, differential potency in vivo and immunoehemistry stain. The isolated cells were differentiated by serial induction method that mimicking the intrinsic developmental process of the neural system. Results The isolated cells were positive for alkaline phosphatatse and SSEA-1 （ stage specific embryonic antigen 1 ）. Moreover they were identified pluripotent by differentiation in vivo. Therefore the isolated ceils presented the characters of ESCs. Then the isolated cells were able to differentiate into neuroeytes in vitro. Conclusion Mouse embryonic stem ceils isolation, culture and differentiation system has been established.

关键词： isolation and culture BALB/c mouse embryonic stem cells differentiation neurocyte

基于MEH-PPV/Ir(ppy)_3聚合物电双稳器件

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发光学报 2017年第5期38卷 611-616页

作者：王敏胡煜峰滕枫北京交通大学光电子技术研究所发光与光信息技术教育部重点实验室北京100044

通过逐层旋涂的方法,利用MEH-PPV(Poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene]与Ir(ppy)_3(tris(2-phenylpyridine)iridium(Ⅲ))),制备活性层,实现了高性能的电双稳器件。通过改变MEHPPV的浓度,制备了不同器件并进行性能比较,发现所有器件都具有明显的电双稳特性。当MEH-PPV的浓度达到4 mg/mL时,器件的开关比可以达10~3。同时,通过测试器件的电流-循环次数研究了器件的持续稳定特性。经过10~4次的反复读写测试,器件性能依然稳定。最后,通过对器件的Ⅰ-Ⅴ曲线进行线性拟合,并结合器件的能级图,对器件的工作原理进行了研究。结果表明,MEH-PPV/Ir(ppy)_3器件的电双稳特性产生的主要原因是偶极层的形成与破坏。

关键词： MEH-PPV Ir(ppy)3 有机电双稳器件偶极层

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基于脊波变换的扩频水印算法

光电工程 2008年第11期35卷 128-133,138页

作者：胡裕峰朱善安浙江大学电气工程学院杭州310027

针对脊波变换域比小波变换域更适合表示图像线状边缘的奇异性的特征,本文设计出一种新的图像水印算法,即将图像分块脊波变换,在脊波变化域上的高频系数中加性地嵌入经零均值互不相关伪随机序列扩频调制后的水印。实验结果表明,本文算法... 详细信息

针对脊波变换域比小波变换域更适合表示图像线状边缘的奇异性的特征,本文设计出一种新的图像水印算法,即将图像分块脊波变换,在脊波变化域上的高频系数中加性地嵌入经零均值互不相关伪随机序列扩频调制后的水印。实验结果表明,本文算法不仅可以抵抗如压缩、加噪、滤波和剪切等各种常见攻击,还能抵抗图像灰度增强和减弱攻击,与小波域水印算法的比较也说明了本文算法的优势。

关键词：脊波变换有限脊波变换 Radon变换扩频调制抗几何攻击盲提取

基于双混沌置乱和扩频调制的彩色图像盲水印算法

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光学学报 2008年第9期28卷 1691-1696页

作者：胡裕峰朱善安浙江大学电气工程学院浙江杭州310027

提出了一种新的适应彩色图像的盲水印算法,先对宿主图像的绿色分量以8×8像素分块进行离散余弦变换(DCT)变换,用logistic映射生成两个混沌序列,然后用混沌序列置乱加密二值水印图像,并用两个互不相关的伪随机序列扩频调制水印,最后将调... 详细信息

提出了一种新的适应彩色图像的盲水印算法,先对宿主图像的绿色分量以8×8像素分块进行离散余弦变换(DCT)变换,用logistic映射生成两个混沌序列,然后用混沌序列置乱加密二值水印图像,并用两个互不相关的伪随机序列扩频调制水印,最后将调制好的水印嵌入到DCT变换域的中频子带系数上,进行分块DCT反变换得到水印化图像。提取水印时,通过比较两个伪随机序列和水印化图像的相关性大小来提取水印,不需要原始图像的参与,为盲提取水印算法。实验结果证明本文算法能有效地抵抗JPEG压缩、加噪、剪切等常见攻击,绿色分量嵌入水印比红色和蓝色分量嵌入水印能更好地抵抗JPEG压缩的攻击。

关键词：信息光学数字水印双混沌置乱扩频调制绿色分量盲水印

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以故障前补偿电压为基准量的距离继电器研究

中国电机工程学报 2006年第16期26卷 27-32页

作者：胡玉峰柳焕章广东电网公司佛山供电局调度中心广东省佛山市528000 华中电力调度通信中心湖北省武汉市430074

以相量平面法与阻抗平面法为分析手段,提出一种以故障前补偿电压为基准量的故障分量距离继电器构成方法。通过对该方法的研究,揭示了目前常用的基于故障分量的距离继电器的通用表达式与动作特性,对比了这几类距离继电器在可靠性与灵敏... 详细信息

以相量平面法与阻抗平面法为分析手段,提出一种以故障前补偿电压为基准量的故障分量距离继电器构成方法。通过对该方法的研究,揭示了目前常用的基于故障分量的距离继电器的通用表达式与动作特性,对比了这几类距离继电器在可靠性与灵敏性上的差异。最后,结合文章提出的方法,对利用通用表达式构成快速距离继电器进行了研究,给出了具体的构成方法。据此方法可明显地改善目前距离继电器的动作速度,并方便地构造新型快速距离继电器。

关键词：电力系统故障分量电抗继电器多相补偿继电器姆欧继电器补偿电压

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基于PCA和混沌置乱的零水印算法

浙江大学学报（工学版） 2008年第4期42卷 593-597页

作者：胡裕峰朱善安浙江大学电气工程学院浙江杭州310027

针对传统的数字水印技术在图像中嵌入水印信息会导致图像在一定程度上的失真,且图像受到各种攻击后难以提取出水印的问题,提出了一种零水印算法,该算法可在不导致图像任何失真的情况下起到版权保护的作用.对图像进行分块和主成分分析(PC... 详细信息

针对传统的数字水印技术在图像中嵌入水印信息会导致图像在一定程度上的失真,且图像受到各种攻击后难以提取出水印的问题,提出了一种零水印算法,该算法可在不导致图像任何失真的情况下起到版权保护的作用.对图像进行分块和主成分分析(PCA),得到图像的主要分量,基于Renyi映射生成混沌序列对图像的主要分量进行位置置乱,比较置乱后相邻主分量系数间的大小生成特征水印.当对待认证图像进行认证时,用同样的方法提取该认证图像的特征水印,比较两特征水印的相似度来判断图像的版权和所有权.实验结果表明,该算法的不可察觉性很好,并对一些常见的攻击,如JPEG压缩、剪裁、加噪、滤波和旋转等有很强的鲁棒性.与小波域内图像零水印算法的比较结果证明了该方法具有更强的鲁棒性.

关键词：主成分分析 Renyi映射随机置乱零水印

Kinetic Characteristics of Neutralizing Antibody Responses Vary among Patients with COVID-19

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Biomedical and Environmental Sciences 2021年第12期34卷 976-983页

作者： LI Ling hua TU Hong Wei LIANG Dan WEN Chun Yan LI An An LIN Wei Yin hu Ke Qi HONG Wen Shan LI yue Ping SU Juan ZHAO San Tao LI Wei yuAN Run yu ZHOU Ping Ping hu feng yu TANG Xiao Ping KE Chang Wen KE Bi Xia CAI Wei Ping Guangzhou Eighth People’s Hospital Guangzhou Medical UniversityGuangzhou 510060GuangdongChina Guangdong Provincial Center for Diseases Control and Prevention Guangzhou 511430GuangdongChina School of Public Health Southern Medical UniversityGuangzhou 510515GuangdongChina Shantou University Medical College Shantou 515063GuangdongChina

Objective The coronavirus disease 2019(COVID-19) pandemic continues to present a major challenge to public health. Vaccine development requires an understanding of the kinetics of neutralizing antibody(NAb) responses to severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Methods In total, 605 serum samples from 125 COVID-19 patients(from January 1 to March 14, 2020)varying in age, sex, severity of symptoms, and presence of underlying diseases were collected, and antibody titers were measured using a micro-neutralization assay with wild-type *** NAbs were detectable approximately 10 days post-onset(dpo) of symptoms and peaked at approximately 20 dpo. The NAb levels were slightly higher in young males and severe cases, while no significant difference was observed for the other classifications. In follow-up cases, the NAb titer had increased or stabilized in 18 cases, whereas it had decreased in 26 cases, and in one case NAbs were undetectable at the end of our observation. Although a decreasing trend in NAb titer was observed in many cases, the NAb level was generally still *** We demonstrated that NAb levels vary among all categories of COVID-19 patients. Longterm studies are needed to determine the longevity and protective efficiency of NAbs induced by SARS-CoV-2.

关键词： Sex Kinetics Neutralizing antibody SARS-CoV-2