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A New Spirostanol Saponin from Dioscorea futshauensis

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Chinese Chemical Letters 2001年第7期12卷 613-616页

作者： Hong Wei LIU Hisayoshi KOBAYASHI ge Xia qu Xin Sheng YAO Department of Natural Products Chemistry Shenyang Pharmaceutical UniversityShenyang 110015 Institute of Molecular&Cellular Biosciences The University of TokyoTokyoJapan 113

A new spirostanol saponin presenting strong activity of inducing morphological deformation of Pyricularia oryzae mycelia was isolated from Dioscorea futshauensis R. Kunth by bioactivity-guided fractionation. The structure was established as (25S)-spirost-5-en-3 beta, 27-diol-3-O- [alpha -L-rhamnopyranosyl (1 -->2)-beta -D glucopyranosyl (1 -->3)]-beta -D-glucopyranoside on the basis of chemical evidences and spectral analysis, especially by 2D-NMR techniques.

关键词： New spirostanol glycoside Dioscorea futshauensis Pyricularia oryzae

Fractal kinetic characteristics for dissolving and leaching processes of strontium residue

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Chinese Journal Of geochemistry 2010年第4期29卷 393-397页

作者： XU Longjun WANG Xingmin qu ge ZHOU Zhengguo YUE Fenhua Key Laboratory of the Exploitation of Southwest Resources and Environmental Disaster Control Engineering of Ministry of Education Chongqing University Chongqing 400044 China College of Environmental andBiological Engineering Chongqing Technology andBusiness University Chongqing 400033 China

The pore structural characteristics of strontium residue were studied with the N2 adsorption method(ASAP2010).The kinetic properties concerning dissolving and leaching strontium waste were described by determining the concentrations of Sr2+,Ba2+ and soluble sulphides in *** results showed that the specific surface area and pore volume increased with decreasing granule diameter,and the micropore surface of the residue was *** the dissolving and leaching processes of strontium residue,soluble ion concentrations increased with decreasing granule diameter of the residue,and the reaction dimension was lower than the fractal dimension of pore ***2+ and soluble sulphide concentrations significantly exceeded the defined standard values,while Ba2+ concentrations did not,either in the dissolving or leaching *** addition,dissolving and leaching reactions selectively occurred on the micropore surface of strontium residue.

关键词：表面分形维数动力学特性浸出过程可溶性硫化物孔隙结构特征锶离子浓度残渣

Ultrasound-guided Transversus Abdominis Plane Block Improves Postoperative Analgesia and Early Recovery in Patients Undergoing Retroperitoneoscopic Urologic Surgeries:A Randomized Controlled Double-blinded Trial

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Chinese Medical Sciences Journal 2016年第3期31卷 137-141页

作者： ge qu Xu-lei Cui Hong-ju Liu Zhi-gang Ji Yu-guang Huang Department of Anesthesiology Peking Union Medical College HospitalChinese Academy of Medical Sciences & Peking Union Medical College Department of Urology Peking Union Medical College HospitalChinese Academy of Medical Sciences & Peking Union Medical College

Objective To evaluate the effects of ultrasound-guided transversus abdominis plane(TAP) block on postoperative analgesia and early recovery in patients undergoing retroperitoneoscopic urologic *** This was a randomized,controlled,double-blinded *** patients scheduled for retroperitoneoscopic urologic surgeries were randomly assigned to two *** TAP received ultrasound-guided TAP block with 0.5% ropivacaine 20 ml at 30 minutes before surgery,and Group C received TAP sham block with normal *** patients received retroperitoneoscopic urologic surgeries under general *** primary outcome was the severity of pain after *** outcomes included opioids consumption,analgesics,postoperative nausea and vomiting,time to Foley catheter removal and to passage of flatus,length of post-anesthesia care unit stay and hospital *** Eighty patients completed the study,forty cases in each *** to the Group C,the Group TAP had lower visual analogue scale pain scores within two postoperative days(all Pgesic usage(12.5% vs. 45.0%,Pged within postoperative three days(57.5% vs. 35.0%,Pque to improve postoperative analgesia and early recovery in patients undergoing retroperitoneoscopic urologic surgeries.

关键词： ultrasound-guided transversus abdominis block retroperitoneoscopic surgery postoperative analgesia postoperative recovery

Carboxylic acid reductases enable intramolecular lactamization reactions

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Green Synthesis and Catalysis 2022年第3期3卷 294-297页

作者： Zongmin Qin Xiaohui Zhang Xianke Sang Wuyuan Zhang ge qu Zhoutong Sun University of Chinese Academy of Sciences Beijing 100049China Tianjin Institute of Industrial Biotechnology Chinese Academy of SciencesTianjin 300308China National Technology Innovation Center of Synthetic Biology Tianjin 300308China

As a versatile type of enzyme,carboxylic acid reductases(CAR)can not only reduce various carboxylic acids to aldehydes in cooperation with cofactors ATP and NADPH but also catalyze the synthesis of amides and esters in the absence of ***,we report an intramolecular cyclization catalyzed by CAR only with the use of ATP to transform amino acids into diverse lactams,includingγ-/δ-/ε-lactams and chiral derivatives *** observed wide substrate scope and selectivity enable potential applications to be *** results demonstrate that CAR-catalyzed lactamization is a promising approach for the synthesis of chiral lactam com-pounds under mild conditions,thereby enriching the toolbox for the biosynthesis of lactams as a viable alternative to purely chemical procedures.

关键词： Biocatalysis Lactams Carboxylic acid reductase Intramolecular cyclization Lactamization

Correlation power attack on a message authentication code based on SM3

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Frontiers of Information Technology & Electronic Engineering 2019年第7期20卷 930-946页

作者： Ye YUAN Kai-ge qu Li-jiWU Jia-weiMA Xiang-min ZHANG Institute of Microelectronics Tsinghua UniversityBeijing100084China National Laboratory for Information Science and Technology Tsinghua UniversityBeijing100084China State Key Laboratory of Cryptography Beijing100094China

Hash-based message authentication code(HMAC)is widely used in authentication and message *** a Chinese hash algorithm,the SM3 algorithm is gradually winning domestic market value in *** side channel security of HMAC based on SM3(HMAC-SM3)is still to be evaluated,especially in hardware implementation,where only intermediate values stored in registers have apparent Hamming distance *** addition,the algorithm structure of SM3 determines the difficulty in HMAC-SM3 side channel *** this paper,a skillful bit-wise chosen-plaintext correlation power attack procedure is proposed for HMAC-SM3 hardware *** attack experiments on a field programmable gate array(FPGA)board have been *** results show that we can recover the key from the hypothesis space of 2256 based on the proposed procedure.

关键词： HMAC-SM3 Side channel analysis Correlation power attack Bit-wise chosen-plaintext

基于声学分析的女高音声区划分及换声点确认方法

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中国音乐学 2014年第1期 114-120页

作者：屈歌河南理工大学中央音乐学院

在标准录音室内采录三位女高音演唱元音"a"的声音样本,综合分析这些女高音全音域各音的频率、可见谐音个数、基音强度、一二三谐音强度差及包络类型等参量,以这些客观参量为依据,在以往主要以教师主观听觉或歌者自身感受为判断之外,提... 详细信息

在标准录音室内采录三位女高音演唱元音"a"的声音样本,综合分析这些女高音全音域各音的频率、可见谐音个数、基音强度、一二三谐音强度差及包络类型等参量,以这些客观参量为依据,在以往主要以教师主观听觉或歌者自身感受为判断之外,提出一个女高音声区划分及换声点确认的新的客观方法。

关键词：声区划分换声点一二三谐音强度差波形包络谐音个数

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唱词清晰度研究的理论与方法

人民音乐 2023年第8期 72-76页

作者：屈歌西安音乐学院

我国的歌唱艺术品种繁多、形式多样,从戏曲、曲艺到当代的民族声乐或者说中国声乐,无不对唱词重视者加。20世纪现代专业音乐教育的兴起以来,有关民族声乐咬字吐字、以字行腔、字领腔行、腔词关系等专业研究的论述层出不穷。不论是应尚... 详细信息

我国的歌唱艺术品种繁多、形式多样,从戏曲、曲艺到当代的民族声乐或者说中国声乐,无不对唱词重视者加。20世纪现代专业音乐教育的兴起以来,有关民族声乐咬字吐字、以字行腔、字领腔行、腔词关系等专业研究的论述层出不穷。不论是应尚能“以字行腔”的倡议、傅雪漪“(歌唱)声音要服从语言”的观点,①还是当年的“土洋之争”,其探讨的焦点均是针对唱词清晰、准确表达的问题。近来,语音通讯、人机语言工程领域对语言清晰度的理论研究与相关技术日臻成熟,这也为唱词语音的实验研究提供了新的可能。倘若合理借用这种研究思路和方法,则可在客观层面测量唱词“字正”的程度--唱词清晰度的高低,分析、探索隐藏其后的深层原因,研讨唱词发出与传递过程中的特点规律,为民族声乐的理论研究与实践发展助力。

关键词：民族声乐专业音乐教育以字行腔应尚能中国声乐咬字吐字语言清晰度土洋之争

Rational design of geranylgeranyl diphosphate synthase enhances carotenoid production and improves photosynthetic efficiency in Nicotiana tabacum

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Science Bulletin 2022年第3期67卷 315-327页

作者： Chen Dong ge qu Jinggong Guo Fang Wei Shuwen Gao Zhoutong Sun Lifeng Jin Xuwu Sun Jean-David Rochaix Yuchen Miao Ran Wang Zhengzhou Tobacco Research Institute Zhengzhou 450001China Key Laboratory of Plant Stress Biology State Key Laboratory of Cotton BiologySchool of Life SciencesHenan UniversityKaifeng 475001China College of Biological Engineering Henan University of TechnologyZhengzhou 450001China Tianjin Institute of Industrial Biotechnology Chinese Academy of SciencesTianjin 300308China School of Agricultural Sciences Zhengzhou UniversityZhengzhou 450001China Departments of Molecular Biology and Plant Biology University of GenevaGeneva 1211Switzerland

Restricted genetic diversity can supply only a limited number of elite genes for modern plant cultivation and *** this study,we demonstrate that rational design enables the engineering of geranyl-geranyl diphosphate synthase(NtGGPPS),an enzyme of the methylerythritol phosphate pathway(MEP)in the model plant Nicotiana *** the crucial bottleneck in carotenoid biosynthesis,NtGGPPS1 interacts with phytoene synthase(NtPSY1)to channel GGPP into the production of *** of this enzyme in the ntggpps1 mutant leads to decreased carotenoid *** the aim of enhanc-ing NtGGPPS1 activity,we undertook structure-guided rational redesign of its substrate binding pocket in combination with sequence *** activity of the designed NtGGPPS1(a pentuple mutant of five sites V154A/I161L/F218Y/I209S/V233E,d-NtGGPPS1)was measured by a high-throughput colorimetric assay.d-NtGGPPS1 exhibited significantly higher conversion of IPP and each co-substrate(DMAPP~1995.5-fold,GPP~25.9-fold,and FPP~16.7-fold)for GGPP synthesis compared with wild-type ***,the transient and stable expression of d-NtGGPPS1 in the ntggpps1 mutant increased carotenoid levels in leaves,improved photosynthetic efficiency,and increased biomass relative to *** findings provide a firm basis for the engineering of GGPPS and will facilitate the development of quality and yield *** results open the door for the structure-guided rational design of elite genes in higher plants。

关键词： Rational design Carotenoid Methylerythritol phosphate pathway(MEP) geranylgeranyl diphosphate synthase(GGPPS) Nicotiana tabacum

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大型船厂工业刚性地坪结构设计方法研究

工程力学 2016年第B6期33卷 133-137页

作者：吴毅彬黄延瞿革厦门理工学院土木工程与建筑系福建厦门361024 中船第九设计研究院工程有限公司上海200063

为了解大型船厂工业地坪的实际力学性能与计算方法,通过对目前常用道路工程中多层弹性体系与土建弹性地基板两类模型的适用性进行分析,并结合船厂地坪特点,提出基于文克尔地基的多层弹性地基板模型,并对地坪分块名义刚度计算方法及地坪... 详细信息

为了解大型船厂工业地坪的实际力学性能与计算方法,通过对目前常用道路工程中多层弹性体系与土建弹性地基板两类模型的适用性进行分析,并结合船厂地坪特点,提出基于文克尔地基的多层弹性地基板模型,并对地坪分块名义刚度计算方法及地坪层间界面状态进行研究。计算结果表明:不同区域分块弹簧刚度设置起到了调节沉降变形曲线的作用,同时设置地坪层间滑动特性,地坪面层结构受力接近于板式构件受力状态。相关研究成果为制定相应设计计算方法及指导工程设计提供有益参考。

关键词：大型船厂工业地坪多层弹性地基板计算方法数值模型