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A new cyclodipeptide from the cultures of Geotrichum candidum

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chinese Chemical Letters 2007年第9期18卷 1081-1083页

作者： Ya Nan liu Jing Hua xue Na feng Ping Wu Xing Zhong liu Xiao Yi Wei South china Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China institute of Microbiology Chinese Academy of Sciences Beijing 10080 China Graduate University of chinese academy of sciences Beijing 100049 China

A new cyclodipeptide, cyclo(phenylalanyl-N-methyltyrosyl) 1, was isolated from the mycelial solid cultures of Geotrichum candidum. Its structure was elucidated by spectroscopic methods. The antifungal activity of the ... 详细信息

关键词： Cyclo(phenylalanyl-N-methyltyrosyl) Cyclodipeptide Geotrichum Geotrichum candidum Peronophythora litchi Antifungal activity

Recent Progress in Symplectic Algorithms for Use in Quantum Systems

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Communications in Computational physics 2007年第1期2卷 1-53页

作者： xue-Shen liu Yue-Ying Qi Jian-feng He Pei-Zhu Ding institute of Atomic and Molecular physics Jilin UniversityChangchun 130012P.R.China. School of Electrical Engineering Jiaxing UniversityJiaxing 314001P.R.China. Department of physics School of ScienceBeijing Institute of TechnologyBeijing 100081P.R.China.

In this paper we survey recent progress in symplectic algorithms for use in quantum systems in the following topics:Symplectic schemes for solving Hamiltonian systems;Classical trajectories of diatomic systems,model molecule A2B,Hydrogen ion H+2 and elementary atmospheric reaction N(4S)+O2(X 3Σ−g)→NO(X 2Π)+O(3P)calculated by means of Runge-Kutta methods and symplectic methods;the classical dissociation of the HF molecule and classical dynamics of H+2 in an intense laser field;the symplectic form and symplectic-scheme shooting method for the time-independent Schr¨odinger equation;the computation of continuum eigenfunction of the Schr¨odinger equation;asymptotic boundary conditions for solving the time-dependent Schr¨odinger equation of an atom in an intense laser field;symplectic discretization based on asymptotic boundary condition and the numerical eigenfunction expansion;and applications in computing multi-photon ionization,above-threshold ionization,Rabbi oscillation and high-order harmonic generation of laser-atom interaction.

关键词： Quantum system symplectic algorithm classical trajectory Schr¨odinger equation intense laser field.

Anomalous Western Pacific Subtropical High during El Nino Developing Summer in Comparison with Decaying Summer

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Advances in atmospheric sciences 2018年第3期35卷 360-367页

作者： feng xue Xiao DONG Fangxing FAN International Center for Climate and Environment sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The anomalous behavior of the western Pacific subtropical high （WPSH） in E1 Nifio developing summer is studied based on the composite results of eight major E1 Nifio events during 1979-2013. It is shown that the WPSH tends to retreat eastwards with weak intensity during the developing summer. The anomaly exhibits an intraseasonal variation with a weaker anomaly in June and July and a stronger anomaly in August, indicating that different underlying physical mechanisms may be responsible for the anomalous WPSH during early and late summer periods. In June and July, owing to the cold advection anomaly characterized as a weak northerly anomaly from high latitudes, geopotential height in East Asia is reduced and the WPSH tends to retreat eastwards slightly. By contrast, enhanced convection over the warm pool in August makes the atmosphere more sensitive to E1 Nifio forcing. Consequently, a cyclonic anomaly in the western Pacific is induced, which is consistent with the seasonal march of atmospheric circulation from July to August. Accordingly, geopotential height in the western Pacific is reduced significantly, and the WPSH tends to retreat eastwards remarkably in August. Different from the developing summer, geopotential height in the decaying summer over East Asia and the western Pacific tends to enhance and extend northwards from June to August consistently, reaching the maximum anomaly in August. Therefore, the seasonal march plays an important role in the WPSH anomaly for both the developing and decaying summer.

关键词： western Pacific subtropical high El Nifio developing summer decaying summer seasonal march

Defective mitochondrial function by mutation in THICK ALEURONE 1 encoding a mitochondrion-targeted single-stranded DNA-binding protein leads to increased aleurone cell layers and improved nutrition in rice

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Molecular Plant 2021年第8期14卷 1343-1361页

作者： Dong-Qi Li Xiao-Ba Wu Hai-feng Wang xue feng Shi-Juan Yan Sheng-Yang Wu Jin-Xin liu xue-feng Yao Ai-Ning Bai Heng Zhao Xiu-Fen Song Lin Guo Shi-Yong Zhang Chun-Ming liu Key Laboratory of Plant Molecular Physiology Institute of BotanyChinese Academy of SciencesBeijing 100093China University of chinese academy of sciences Beijing 100864China Rice Research institute Shandong Academy of Agricultural SciencesJinan 250100China Guangdong Key Laboratory for Crop Germplasm Resources Preservation and Utilization Agro-biological Gene Research CenterGuangdong Academy of Agricultural SciencesGuangzhou 510640China lnstitute of Crop sciences Chinese Academy of Agricultural SciencesBeijing 100081China School of Advanced Agricultural sciences Peking UniversityBeijing 100871China Innovative academy of Seed Design Chinese Academy of SciencesBeijing 100101China

Cereal endosperm comprises an outer aleurone and an inner starchy *** these two tissues have the same developmental origin,they differ in morphology,cell fate,and storage product accumulation,with the mechanism largely ***,we report the identification and characterization of rice thick aleurone 1(ta1)mutant that shows an increased number of aleurone cell layers and increased contents of nutritional factors including proteins,lipids,vitamins,dietary fibers,and *** identified that the TA1 gene,which is expressed in embryo,aleurone,and subaleurone in caryopses,encodes a mitochondrion-targeted protein with single-stranded DNA-binding activity named *** analyses revealed that the increased aleurone cell layers in ta1 originate from a developmental switch of subaleurone toward aleurone instead of starchy endosperm in the wild *** found that TA1/OsmtSSB1 interacts with mitochondrial DNA recombinase RECA3 and DNA helicase TWINKLE,and downregulation of REC A3 or TWINKLE also leads to ta1-like *** further showed that mutation in TA1/OsmtSSB1 causes elevated illegitimate recombinations in the mitochondrial genome,altered mitochondrial morphology,and compromised energy supply,suggesting that the OsmtSSB1-mediated mitochondrial function plays a critical role in subaleur one cell-fate determination in rice.

关键词： rice thick aleurone cell-fate determination nutritional improvement mitochondria

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固原黄牛不同部位肌肉组织代谢组学分析

畜牧兽医学报 2024年第4期55卷 1565-1578页

作者：王中波刘爽贺丽霞冯雪杨梦丽汪书哲刘源冯兰丁晓玲冀国尚杨润军张路培马云宁夏大学动物科技学院宁夏回族自治区反刍动物分子细胞育种重点实验室银川750021 吉林大学动物科学学院长春130000 中国农业科学院北京畜牧兽医研究所北京100193

旨在探究与固原黄牛肉风味形成相关的关键代谢物、代谢途径和酶,为深入解析固原黄牛肉肉品组成提高肉品质量奠定基础。本研究选用同一生长条件下,24月龄的6头健康雄性固原黄牛作为研究对象,利用非靶向代谢组学技术对眼肉、肩肉和臀肉3... 详细信息

旨在探究与固原黄牛肉风味形成相关的关键代谢物、代谢途径和酶,为深入解析固原黄牛肉肉品组成提高肉品质量奠定基础。本研究选用同一生长条件下,24月龄的6头健康雄性固原黄牛作为研究对象,利用非靶向代谢组学技术对眼肉、肩肉和臀肉3个组进行代谢物分析鉴定,通过主成分分析、偏最小二乘法判别分析和聚类分析筛选差异代谢物,并对筛选结果进行富集分析。随后,利用FELLA分析调控不饱和脂肪酸合成代谢相关的途径以及潜在的关键代谢物,同时对差异代谢物进行WGCNA分析。代谢物分析结果显示,固原黄牛眼肉、肩肉和臀肉3个组共鉴定出689个代谢物,其中脂质和类脂分子占比32.08%,脂肪酸类代谢物49种,聚类分析肩肉组和臀肉组样本聚为一类,眼肉组样本单独为一类。N6,N6,N6-三甲基-L-赖氨酸(N6,N6,N6-trimethyl-L-lysine)和麦芽三糖(maltotriose)是眼肉、肩肉和臀肉组与组之间共同的差异代谢物,二者含量均在眼肉最高。KEGG通路分析显示,差异代谢物主要富集在不饱和脂肪酸生物合成、嘌呤代谢、丙氨酸、天冬氨酸和谷氨酸代谢等代谢通路。通过WGCNA分析筛选出与3个肌肉部位相关的模块,并鉴定出了各模块中的关键代谢物。本研究通过对固原黄牛不同部位肌肉组织进行代谢组学分析,鉴定到与肉品质差异和风味形成相关的10种关键代谢物和17种关键酶,为今后探究固原黄牛肉风味形成的分子调控机制和分子育种提供理论基础,同时也为其他肉牛的品质性状育种提供参考。

关键词：固原黄牛非靶向代谢组学风味不饱和脂肪酸分子育种

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内蒙边境沿线生活饮用水水质安全评价

军事医学 2018年第1期42卷 26-28,48页

作者：张熙遥张灿胡晓丰戚红卷史云白淼安代志王莉莉刘雪林张传福解放军疾病预防控制所北京100071 军事科学院军事医学研究院北京100850

目的了解内蒙边境沿线生活饮用水的卫生状况,针对饮用水的水质开展安全评价研究,为相关部门改善水质提供基础性参考。方法采集内蒙边境沿线生活饮用水样品108份(自备水源水70份、自备供水末梢水21份和市政末梢水17份),依据GB 5749—200... 详细信息

目的了解内蒙边境沿线生活饮用水的卫生状况,针对饮用水的水质开展安全评价研究,为相关部门改善水质提供基础性参考。方法采集内蒙边境沿线生活饮用水样品108份(自备水源水70份、自备供水末梢水21份和市政末梢水17份),依据GB 5749—2006《生活饮用水卫生标准》对水质的感官性状指标、一般化学指标、毒理学指标以及微生物学指标进行卫生学评价。结果 108份检测水样中,合格58份,总合格率为53.7%。其中,总大肠菌群不合格率最高(20.4%),其次是氟化物(19.4%);深井水、浅井水和地表水的不合格率比较,差异无统计学意义;自备供水末梢水的不合格率(28.6%)稍高于市政末梢水(17.7%)。结论内蒙边境沿线生活饮用水合格率偏低,微生物指标超标最严重,部分地区氟化物超标。建议增加饮用水水处理消毒设施和水质检测设备,定期对自备供水单位储存水箱进行去垢消毒和保洁维护,同时加大监测力度,防止水性传染病的发生。

关键词：生活饮用水内蒙边境沿线水质检测卫生学评价

New insights into the mechanism of surfactant enhanced oil recovery:Micellar solubilization and in-situ emulsification

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Petroleum Science 2022年第2期19卷 870-881页

作者： xue-Zhi Zhao Guang-Zhi Liao Ling-Yan Gong Huo-Xin Luan Quan-Sheng Chen Wei-Dong liu Dong liu Yu-Jun feng Polymer Research institute State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065People's Republic of China Petrochina Exploration&Production Company Beijing100007People's Republic of China Research institute of Experiment and Detection Xinjiang Oilfield Branch CompanyPetroChinaKaramay834000People's Republic of China Research institute of Petroleum Exploration&Development PetroChina Company LimitedBeijing100083People's Republic of China institute of Nuclear physics and Chemistry China Academy of Engineering PhysicsMianyang621000People's Republic of China

Reducing the oil-water interfacial tension(IFT)to ultra-low is believed the primary mechanism for surfactant-based enhanced oil recovery(EOR)***,field trials have shown that low concentration surfactant flooding can also improve oil recovery without ultra-low *** clarify the mechanism behind,the currently-used surfactant,naphthenic arylsulfonate(NAS),was used to unravel its function during surfactant flooding from the horizon of micron-and *** solubilization capacity of NAS micelle to petroleum fractions was evaluated through light absorbance strategy,smallangle neutron scattering,dynamic light scattering and transmission electron *** was found that micellar solubilization plays a significant role during the surfactant ***-situ emulsification was visualized in microfluidics with three types of microchips,respectively.A series of displacement tests were carried out with NAS solution pumping into oil-saturated *** results show that in-situ emulsification improve oil recovery mainly through blocking and entrainment *** from this work aid in understanding the interaction between surfactant solution and petroleum fractions at low surfactant concentration,which is helpful for design surfactant-based displacing system for EOR process.

关键词： Enhanced oil recovery Surfactant flooding Micellar solubilization Microfluidics In-situ emulsification

基于RPA-CRISPR/Cas12a的美国白蛾可视化快速检测新方法

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环境昆虫学报 2024年第5期46卷 1051-1058页

作者：王雅娜于艳雪田茜张柳李红卫杨硕翟俊峰中国检验检疫科学研究院植物检验与检疫研究所北京100176

美国白蛾Hyphantria cunea Drury是我国重要林业害虫,寄主植物众多且分布范围广泛。本试验基于重组酶聚合酶扩增(RPA)和CRISPR检测技术,构建美国白蛾RPA-CRISPR/Cas12a分子检测体系。根据NCBI数据库中的美国白蛾及近缘种、近似种线粒体C... 详细信息

美国白蛾Hyphantria cunea Drury是我国重要林业害虫,寄主植物众多且分布范围广泛。本试验基于重组酶聚合酶扩增(RPA)和CRISPR检测技术,构建美国白蛾RPA-CRISPR/Cas12a分子检测体系。根据NCBI数据库中的美国白蛾及近缘种、近似种线粒体COⅠ基因片段信息以及昆虫样本CO I基因测序比对结果为模板,设计美国白蛾特异性RPA引物和CrRNA,通过RPA扩增目标序列,结合CRISPR检测技术并对反应条件进行优化,最终该体系灵敏度可检测的最低限度1.0×10^(-1) ng/μL,较RPA结合普通凝胶电泳提高了100倍,检测体系在30 min内即可实现对害虫的现场快速、可视化、精准鉴定。为美国白蛾现场检测提供理论和实践依据,有助于保护森林资源和生态环境的安全。

关键词：美国白蛾 RPA CRISPR Cas12a 可视化快速检测

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光丝激光在大气中的传输及中红外波谱特性

量子光学学报 2024年第2期30卷 108-120页

作者：冯志芳郝婷刘勋刘丽娜李维舒小芳刘渊太原科技大学应用科学学院山西省光场调控与融合应用技术创新中心山西太原030024 中国空间技术研究院、北京空间机电研究所北京100094 北京量子信息科学研究院北京100088

本文通过数值模拟,利用大气分层模型,研究了强飞秒激光脉冲在距地面1 km以内不同高度处产生光丝,分析了压强、束腰宽度、脉宽以及散射介质的衰减对光丝传输特性和超连续波谱的影响。结果表明,压强的微小变化导致光丝特性的显著变化,从... 详细信息

本文通过数值模拟,利用大气分层模型,研究了强飞秒激光脉冲在距地面1 km以内不同高度处产生光丝,分析了压强、束腰宽度、脉宽以及散射介质的衰减对光丝传输特性和超连续波谱的影响。结果表明,压强的微小变化导致光丝特性的显著变化,从而直接影响超连续波谱的特性。在不同束宽和脉宽下,等离子体丝激发的波谱覆盖了整个可见光波长范围,并延伸到中红外波段,适当地减小束宽和脉宽,可以增强波谱强度和扩展红移截止波长,并且波谱的强度与光丝的长度及稳定性有关,而波谱的红移由光丝的动力学特性决定。散射介质(包括雨滴、雾和气溶胶)对光丝传输特性有较大的影响,但当初始参数选取合适时,衰减对超连续波谱中的中红外波谱强度和展宽的影响是比较小的。此研究为利用中红外波谱探测不同高度处大气污染物成分提供了重要的理论依据。

关键词：强飞秒激光脉冲中红外波谱压强散射介质光丝