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基于转录组测序的毛萼香茶菜Ⅱ型二萜合酶的挖掘与功能鉴定

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中国医药生物技术 2024年第3期19卷 206-213页

作者：梅一婷梁苗苗李静一贾美荣中国医学科学院北京协和医学院药物研究所天然药物活性物质与功能国家重点实验室/国家卫生健康委员会天然药物生物合成重点实验室/中国医学科学院酶与天然药物生物催化重点实验室北京100050

目的从毛萼香茶菜中挖掘Ⅱ型二萜合酶并进行功能鉴定。方法利用转录组测序和生物信息学分析技术从毛萼香茶菜的根、茎、叶、顶芽4种组织中挖掘Ⅱ型二萜合酶候选基因,通过RT-PCR方法获取候选基因cDNAs,运用无缝克隆技术构建携带候选基因... 详细信息

目的从毛萼香茶菜中挖掘Ⅱ型二萜合酶并进行功能鉴定。方法利用转录组测序和生物信息学分析技术从毛萼香茶菜的根、茎、叶、顶芽4种组织中挖掘Ⅱ型二萜合酶候选基因,通过RT-PCR方法获取候选基因cDNAs,运用无缝克隆技术构建携带候选基因的表达载体,并基于大肠杆菌异源表达体系及GC-MS测定分析技术进行二萜合酶基因的催化功能鉴定。结果分别从毛萼香茶菜的根、茎、叶、顶芽组织中提取总RNA,经过转录组测序和生物信息学分析获得4个Ⅱ型二萜合酶候选基因IeTPS1、IeTPS2、IeTPS3和IeTPS4。利用大肠杆菌异源表达体系对其中的IeTPS1和IeTPS4基因进行功能验证,发现IeTPS1能够催化底物香叶基香叶基焦磷酸(GGPP)生成对映-柯巴基焦磷酸(ent-CPP),命名为IeCPS4;IeTPS4能够催化底物GGPP生成柯巴基焦磷酸(normal-CPP),命名为IeCPS5。结论从毛萼香茶菜中筛选并鉴定了两个新的Ⅱ型二萜合酶基因IeCPS4和IeCPS5,其中IeCPS5是首个从毛萼香茶菜中发现的专一合成normal-CPP的二萜合酶基因,这不仅丰富了毛萼香茶菜的二萜合酶种类,而且为毛萼香茶菜二萜化合物生物合成途径的解析奠定了坚实基础。

关键词：毛萼香茶菜转录组测序二萜合酶萜类生物合成功能验证

Dramatic decline of observed atmospheric CO_(2) and CH_(4) during the COVID-19 lockdown over the Yangtze River Delta of China

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Journal of Environmental Sciences 2023年第2期124卷 712-722页

作者： miao liang Yong Zhang Qianli Ma Dajiang Yu Xiaojian Chen Jason Blake Cohen Meteorological Observation Center China Meteorological AdministrationBeijing 100081China Lin’an Atmospheric Regional Background Station China Meteorological Administration(CMA)Hangzhou 311307China Longfengshan Regional Background Station China Meteorological Administration(CMA)Heilongjiang 150200China Shanxi Meteorological Information Center China Meteorological Administration(CMA)Shanxi 030000China School of Environment and Spatial Informatics China University of Mining and TechnologyXuzhou221116China

The temporal variation of greenhouse gas concentrations in China during the COVID-19 lockdown in China is analyzed in this work using high resolution measurements of near surface ΔCO_(2),ΔCH_(4) andΔCO concentrations above the background conditions at Lin’an station(LAN),a regional background station in the Yangtze River Delta *** the pre-lockdown observational period(IOP-1),bothΔCO_(2) andΔCH_(4) exhibited a significant increasing trend relative to the 2011-2019 climatological *** reduction ofΔCO_(2),ΔCH_(4) andΔCO during the lockdown observational period(IOP-2)(which also coincided with the Chinese New Year Holiday)reached up to 15.0 ppm,14.2 ppb and 146.8 ppb,respectively,and a reduction ofΔCO_(2)/ΔCO probably due to a dramatic reduction from industrial emissions.ΔCO_(2),ΔCH_(4) and ΔCO were observed to keep declining during the post-lockdown easing phase(IOP-3),which is the synthetic result of lower than normal CO_(2) emissions from rural regions around LAN coupled with strong uptake of the terrestrial ***,the trend reversed to gradual increase for all species during the later easing phase(IOP-4),with ΔCO_(2)/ΔCO constantly increasing from IOP-2 to IOP-3 and finally IOP-4,consistent with recovery in industrial emissions associated with the staged resumption of economic *** average,ΔCO_(2) declined sharply throughout the days during IOP-2 but increased gradually throughout the days during *** findings showcase the significant role of emission reduction in accounting for the dramatic changes in measured atmosphericΔCO_(2) and ΔCH_(4) associated with the COVID-19 lockdown and recovery.

关键词： Atmospheric CO_(2) Atmospheric CH_(4) COVID-19 lockdown The Yangtze river delta

Convergence analysis of an incremental approach to online inverse reinforcement learning

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第1期12卷 17-24页

作者： Zhuo-jun JIN Hui QIAN Shen-yi CHEN miao-liang ZHU School of Computer Science and Technology Zhejiang University Hangzhou 310027 China

Interest in inverse reinforcement learning (IRL) has recently increased,that is,interest in the problem of recovering the reward function underlying a Markov decision process (MDP) given the dynamics of the system and the behavior of an *** paper deals with an incremental approach to online ***,the convergence property of the incremental method for the IRL problem was investigated,and the bounds of both the mistake number during the learning process and regret were provided by using a detailed *** an online algorithm based on incremental error correcting was derived to deal with the IRL *** key idea is to add an increment to the current reward estimate each time an action mismatch *** leads to an estimate that approaches a target optimal *** proposed method was tested in a driving simulation experiment and found to be able to efficiently recover an adequate reward function.

关键词： Incremental approach Reward recovering Online learning Inverse reinforcement learning Markov decision process

北京市3岁前儿童非免疫规划疫苗接种状况与趋势研究

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首都公共卫生 2024年第2期18卷 65-68页

作者：纪文艳虞睿苗良索罗丹北京市疾病预防控制中心 100013

目的了解北京市3岁前儿童非免疫规划(non-expanded programme on immunization,non-EPI)疫苗接种水平和变化趋势,为加强对非EPI疫苗管理提供参考。方法2023年9月1日,采用系统抽样方法随机抽取北京市免疫规划信息管理系统中2011、2014、2... 详细信息

目的了解北京市3岁前儿童非免疫规划(non-expanded programme on immunization,non-EPI)疫苗接种水平和变化趋势,为加强对非EPI疫苗管理提供参考。方法2023年9月1日,采用系统抽样方法随机抽取北京市免疫规划信息管理系统中2011、2014、2017和2020年的8月份出生的所有儿童个案,分析各年份抽样儿童3岁前接种非EPI疫苗的种类及户籍分布、首剂接种比例、全程免疫完成比例及其变化趋势。结果研究对象共108210名。非EPI疫苗总剂次分别为88019、109442、104451和130501剂次。研究对象3岁前水痘疫苗、肠道病毒71型灭活疫苗(EV71疫苗)和吸附无细胞百白破灭活脊髓灰质炎和b型流感嗜血杆菌(结合)联合疫苗(DTaP-IPV-Hib五联疫苗)首剂接种比例均逐年增加,由最初的<10%分别增加至82.20%、61.07%和39.20%;2020年研究对象中,接种总剂次居前5位的非免疫规划疫苗是13价肺炎疫苗、DTaP-IPV-Hib五联疫苗、EV71疫苗、5价轮状病毒疫苗和水痘疫苗,首剂接种比例分别为48.30%、39.20%、61.07%、30.58%和82.20%,京籍儿童均高于非京籍儿童(P<0.05);3岁前DTaP-IPV-Hib五联疫苗、EV71疫苗和5价轮状病毒疫苗在接种首剂后的多剂次疫苗的全程免疫完成比例分别为92.26%、96.56%和94.37%,京籍儿童均高于非京籍儿童(P<0.05)。结论北京市3岁前儿童非EPI疫苗接种数量和新疫苗种类不断增加,全程接种依从性较高。而在非EPI疫苗的首剂接种比例和非京籍儿童中均需进一步提高。建议开展相关影响因素研究,加强非免疫规划疫苗的技术指导,进一步提高全市非免疫规划疫苗接种数量和质量。

关键词：儿童非免疫规划疫苗接种比例北京

机器人辅助腹腔镜技术在腹股沟淋巴结切除术中的应用

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机器人外科学杂志（中英文） 2024年第3期5卷 489-494页

作者：李永康梁苗王延洲陈诚重庆市人民医院妇产科重庆401147 陆军军医大学第一附属医院妇产科重庆400038

腹股沟淋巴结切除术是治疗外阴癌及阴茎癌的重要手术方式之一,传统开放手术容易导致皮肤切口愈合不良、淋巴水肿等并发症发生。随着微创技术的发展,腹腔镜腹股沟淋巴结切除术在外阴癌及阴茎癌治疗中广泛应用,并显示出良好的优势。在传... 详细信息

腹股沟淋巴结切除术是治疗外阴癌及阴茎癌的重要手术方式之一,传统开放手术容易导致皮肤切口愈合不良、淋巴水肿等并发症发生。随着微创技术的发展,腹腔镜腹股沟淋巴结切除术在外阴癌及阴茎癌治疗中广泛应用,并显示出良好的优势。在传统腹腔镜发展基础上,机器人手术系统应运而生,并以其独特的优势受到临床医生的青睐。机器人辅助腹腔镜腹股沟淋巴结切除术在外阴癌及阴茎癌治疗中已应用10多年,研究显示其在保证肿瘤治疗效果的同时降低了手术并发症。本文就机器人辅助腹腔镜腹股沟淋巴结切除术的发展历程及在上述两种肿瘤中的应用做一综述。

关键词：机器人辅助手术腹股沟淋巴结清扫术外阴癌阴茎癌

Synthesis of Novel Monophosphoramidite Ligands Derived from L-Proline for Rh-catalyzed Asymmetric Hydrogenation of α-Dehydroamino Acid Esters

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Chinese Chemical Letters 2005年第10期16卷 1321-1323页

作者： Qing Heng ZENG Xiang Ping HU Xin miao liang Zhuo ZHENG Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 Graduate School of Chinese Academy of Sciences Beijing 100039

Two novel monophosphoramidites were synthesized through a five-step transformation from commercially available L-proline. In the Rh-catalyzed asymmetric hydrogenation of α-dehydroamino acid derivatives, ligand （Sc,... 详细信息

关键词： Monophosphoramidite L-proline Rh-catalyzed asymmetric hydrogenation α-dehydroamino acid.

The Study on the Noncovalent Complexes of Silver Ion with Xanthone Diglycosides by Electrospray Ionization with Tandem Mass Spectrometry

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Chinese Chemical Letters 2006年第3期17卷 391-394页

作者： Yan Guo SUN Xi ZHANG Hong Bin XIAO Xin miao liang Dalian Institute of Chemical Physics Chinese Academy of Science Dalian 116023

The silver ionic complexes of xanthone glycosides were studied by ESI-MS/MS in the positive ion mode. The fragmentation pathways of silver ionic complexes under collisioninduced dissociation （CID） were investigated and the differences in MS/MS spectra of different silver ionic complexes of xanthones were correlated to the characterization of saccharide and the coordination pattern of silver ion with xanthones, including the glycosilation position and linkage type of disaccharide （1-2 and 1-6 linkages）.

关键词： Electrospray ionization MS/MS xanthone glycosides silver ionic complexes

参数智能优化变分模态分解的输电短路信号提取

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制造业自动化 2024年第4期46卷 87-92,101页

作者：裴东锋刘勇李勇苗靓侯帅国网河北省电力有限公司邯郸供电分公司邯郸056000 河北工程大学信息与电气工程学院邯郸056000

输电短路信号因非线性含噪难以准确提取,影响后续故障诊断正确率。为此,提出参数智能优化变分模态分解的输电短路信号提取方法。引入峰值密度实时监测粒子群种群密度,设计权重自适应更新策略,以避免种群多样性缺失导致算法陷入局部最优... 详细信息

输电短路信号因非线性含噪难以准确提取,影响后续故障诊断正确率。为此,提出参数智能优化变分模态分解的输电短路信号提取方法。引入峰值密度实时监测粒子群种群密度,设计权重自适应更新策略,以避免种群多样性缺失导致算法陷入局部最优;然后,建立变分模态分解(Variational Mode Decomposition,简称VMD)算法优化求解的适应度函数,并采用上述改进粒子群算法实现VMD参数智能优化下的输电短路信号提取。采用典型测试函数验证了改进粒子群算法具有比其他算法更好的搜索速度和稳定性,并进一步验证了提出的参数智能优化变分模态分解方法可以较好提取非线性含噪输电短路信号,可提高故障诊断正确率。

关键词：变分模态分解参数优化粒子群优化惯性权重输电短路信号提取

Synthesis of Novel C_(2)-Symmetrical Bidentate Phosphoramidite Ligands for Rh-catalyzed Asymmetric Hydrogenation of β-(Acylamino)acrylates

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Chinese Chemical Letters 2006年第6期17卷 711-713页

作者： Qing Heng ZHNG Xiang Ping HU Xin miao liang Zhuo ZHENG Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023 Graduate School of Chinese Academy of Sciences Beijing 100039

Two new C2-symmetrical bidentate phosphoramidite ligands were synthesized and employed in the Rh-catalyzed asymmetric hydrogenation of β-（acylamino）acrylates, up to 89% ee with full conversions was obtained.

关键词： β-Aminoacid phosphoramidite 1,2-diphenylethylenediamine Rh-catalyzed asymmetric hydrogenation,β-(acylamino)acrylates.