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广播与电视技术 2024年第1期51卷 36-40页

作者：许春蕾崔俊生中央广播电视总台北京100859 国家广电总局广播电视规划院北京100045

中央广播电视总台“百城千屏随身听”业务通过“百城千屏”超高清视音频传播系统使用异构网络额外传输一路节目伴音,在大屏侧实现大屏视频与移动终端上的节目伴音同步呈现。本文阐述了该业务面临的技术挑战和对应的实现方式。

关键词：百城千屏 8K超高清时间戳

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盐酸小檗碱的心血管药理活性研究进展

药学研究 2022年第2期41卷 117-121页

作者：林青薇李沛波吴灏彭维钟华林苏薇薇程春雷王永刚中山大学生命科学学院广东省中药上市后质量与药效再评价工程技术研究中心/广东省热带亚热带植物资源重点实验室广东广州510275 山东省食品药品检验研究院山东济南250101

小檗碱是一种异喹啉生物碱,存在于黄连、黄檗等植物中,临床常用其盐酸盐。盐酸小檗碱具有强心、抗心律失常、内皮保护、心肌保护、降压、抗动脉粥样硬化、糖尿病性心血管疾病治疗等心血管药理活性作用,是一种富有潜力的心血管疾病治疗... 详细信息

小檗碱是一种异喹啉生物碱,存在于黄连、黄檗等植物中,临床常用其盐酸盐。盐酸小檗碱具有强心、抗心律失常、内皮保护、心肌保护、降压、抗动脉粥样硬化、糖尿病性心血管疾病治疗等心血管药理活性作用,是一种富有潜力的心血管疾病治疗药物。本文通过对PubMed数据库进行检索,对盐酸小檗碱的心血管药活性研究进行了综述。

关键词：盐酸小檗碱心血管药理学

维普期刊数据库博看期刊

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盐酸小檗碱肠溶缓释片制剂工艺研究

药学研究 2022年第5期41卷 307-311页

作者：林青薇钟华林李沛波吴灏彭维苏薇薇程春雷王永刚中山大学生命科学学院广东省中药上市后质量与药效再评价工程技术研究中心/广东省热带亚热带植物资源重点实验室广东广州510275 山东省食品药品检验研究院山东济南250101

目的研究盐酸小檗碱肠溶缓释片的制剂工艺。方法采用体外释放度评价的方法,以单因素设计及正交设计筛选片芯处方及工艺,并对片芯进行肠溶包衣,制备盐酸小檗碱肠溶缓释片。结果体外释放度实验显示,片芯及肠溶片均符合Higuchi释药模型。... 详细信息

目的研究盐酸小檗碱肠溶缓释片的制剂工艺。方法采用体外释放度评价的方法,以单因素设计及正交设计筛选片芯处方及工艺,并对片芯进行肠溶包衣,制备盐酸小檗碱肠溶缓释片。结果体外释放度实验显示,片芯及肠溶片均符合Higuchi释药模型。结论盐酸小檗碱肠溶缓释片工艺稳定,体外释放符合设计要求。

关键词：盐酸小檗碱肠溶缓释片体外释放

New insights in the battle between wheat and Puccinia striiformis

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Frontiers of Agricultural Science and Engineering 2015年第2期2卷 101-114页

作者： chunlei TANG Xiaojie WANG Yulin cheng Minjie LIU Mengxin ZHAO Jinping WEI Zhensheng KANG State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection Northwest A&F UniversityYangling 712100China

Wheat stripe rust caused by Puccinia striiformis ***(Pst)poses a great threat to wheat production *** rapid change in virulence of Pst leads to a loss of resistance in currently resistant wheat cultivars,which results in frequent disease ***,a major focus is currently placed on investigating the molecular mechanisms underlying this rapid variation of pathogenicity and coevolving wheat *** by the lack of a system for stable transformation of Pst and the difficulties in wheat transformation,it is not easy to generate deeper insights into the wheat-Pst interaction using established genetic ***,considerable effort has been made to unravel the wheat-Pst interaction and significant progress is being *** and cytology have revealed basic details of infection strategies and defense responses during wheat-Pst interactions,identified cellular components involved in wheat-Pst interactions,and have helped to elucidate their role in the infection process or in plant defense *** and genome sequencing has revealed the molecular features and dynamics of the wheat-Pst *** molecular analyses have led to the identification of major components in the wheat resistance response and in Pst *** of wheat-Pst interactions have now entered a new phase in which cellular and molecular approaches are being *** review focuses on the cellular biology of wheat-Pst interactions and integrates the emerging data from molecular analyses with the histocytological observations.

关键词： wheat strip rust Puccinia striiformis f.sp.tritici host defense pathogen virulence biotrophic fungus

Modern stalagmite oxygen isotopic composition and its implications of climatic change from a high-elevation cave in the eastern Qinghai-Tibet Plateau over the past 50 years

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Chinese Science Bulletin 2007年第9期52卷 1238-1247页

作者： YANG XunLin ZHANG PingZhong CHEN FaHu HUH Chih-an LI HongChun cheng Hai Kathleen R. JOHNSON LIU JingHua AN chunlei CAEP Key Laboratory of Western China's Environmental System of Ministry of Education College of Earth and Environmental Sciences Lanzhou University Lanzhou 730000 China Institute of Earth Sciences 'Academia Sinica' Taipei 115 China Department of Earth Sciences Cheng-Kung University Tainan 700 China Department of Geology and Geophysics University of Minnesota MN 55455 USA Department of Earth Sciences Oxford University Parks Road Oxford OX1 3PR UK

An oxygen isotope record of a stalagmite from Huanglong Cave in the eastern Qinghai-Tibet Plateau dated with 230Th and 210Pb methods provides variations of the Asian monsoon with an average resolu-tion of 1 year over the past 50 years. This study shows that the δ18O of dripwater in the cave represents the annual mean δ18O of local meteoric precipitation and the stalagmites were deposited in isotopic equilibrium. A comparison of the stalagmite δ18O record with instrumentally meteorological data indi-cates that shifts of the δ18O are largely controlled by the amount effect of meteoric precipitation con-veyed through the southwest monsoon(the Indian monsoon) and less affected by temperature. Therefore,the variations of δ18O record reflect the changes in monsoon precipitation on inter-annual time scales under the influence of the southwest monsoon. Like many other stalagmite δ18O records in the Asian monsoon regions,the δ18O record of the stalagmite from Huanglong Cave also reveals a gradually enriched trend during the past 50 years,i.e. relatively enriched in 18O. This trend may indicate the decline of the Asian monsoon intensity which is consistent with the decrease of monsoon indices. The weakening of the modern Asian monsoon well matched with the temperature changes in strato-sphere,which may illustrate that the weakening of the monsoon mainly results from the lowering of solar radiation.

关键词：青藏高原高海拔溶洞现代石笋氧同位素成分气候变化

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不同含糖饮料摄入水平小学生肠道菌群差异

中国学校卫生 2024年第3期45卷 335-340,345页

作者：张琴刘雪婷张可馨田野何春雷王一迪徐裕杰单树方汪晓语熊静远成果何方四川大学华西公共卫生学院(四川大学华西第四医院) 成都610041 四川大学华西第二医院西部妇幼医学研究院妇儿营养中心四川大学华西护理学院

目的探讨不同含糖饮料摄入水平小学生肠道菌群的差异,为更好地识别儿童健康风险并制定有针对性的健康政策提供科学依据。方法于2022年6月,采用分层整群随机抽样方法选取成都市健康小学生192名,采用膳食频率问卷调查含糖饮料摄入量,依据... 详细信息

目的探讨不同含糖饮料摄入水平小学生肠道菌群的差异,为更好地识别儿童健康风险并制定有针对性的健康政策提供科学依据。方法于2022年6月,采用分层整群随机抽样方法选取成都市健康小学生192名,采用膳食频率问卷调查含糖饮料摄入量,依据小学生每日含糖饮料摄入量中位水平分为低摄入组(96名)和高摄入组(96名)。使用16S rRNA高通量测序对两组小学生新鲜粪便标本进行肠道菌群检测,比较两组肠道菌群的多样性和群落结构差异。结果低摄入组小学生含糖饮料摄入量为(21.3±1.6)mL/d,高摄入组摄入量为(269.6±37.3)mL/d。多样性分析结果显示,低摄入组与高摄入组肠道菌群α多样性的可观测的OTU(Observed_otus)指数[298.50(259.75,342.25),305.50(244.25,367.75)],测序深度(Goods_coverage)指数[1.00(1.00,1.00),1.00(1.00,1.00)],Chao指数[304.18(260.75,348.78),305.88(245.68,370.88)],香农(Shannon)指数[5.88(5.29,6.45),5.71(4.89,6.28)],辛普森(Simpson)指数[0.95(0.91,0.97),0.94(0.88,0.97)]差异均无统计学意义(Z值分别为-0.64,-0.76,-0.54,-1.76,-1.67,P值均>0.05);两组肠道菌群的β多样性差异无统计学意义(R^(2)=0.006,P>0.05)。在菌属水平,低摄入组中布劳特氏菌属[0.033(0.018,0.055)]、纺锤链杆属[0.009(0.005,0.015)]丰度均高于高摄入组[0.024(0.013,0.041),0.006(0.003,0.011)],差异均有统计学意义(Z值分别为-2.52,-2.81,P值均<0.05)。LEfSe分析显示两组菌群的组间差异主要体现在布劳特氏菌属、纺锤链杆属及八叠球菌属(LDA值分别为3.56,3.12,3.53,P值均<0.05)。结论不同含糖饮料摄入水平的小学生肠道菌群多样性和整体结构差异不大,但菌属水平存在物种差异,可为识别小学生的健康风险,制定健康对策提供科学依据。

关键词：碳水化合物饮料摄食行为胃肠道细菌儿童

Asian summer monsoon precipitation recorded by stalagmite oxygen isotopic composition in the western Loess Plateau during AD1875―2003 and its linkage with ocean-atmosphere system

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Chinese Science Bulletin 2008年第13期53卷 2041-2049页

作者： LIU JingHua ZHANG PingZhong cheng Hai CHEN FaHu YANG XunLin ZHANG DeZhong ZHOU Jing JIA JiHong AN chunlei SANG WenCui Kathleen R. JOHNSON Key Laboratory of Western China's Environmental System of Ministry of Education College of Earth and Environmental Sciences Lanzhou University Lanzhou 730000 China Department of Geology and Geophysics University of Minnesota Minneapolis MN 55455 USA School of Geographical Sciences Southwest University Chongqing 400715 China Department of Earth System Science University of California Irvine CA 92697 USA

Based on 5 high-precision 230Th dates and 103 stable oxygen isotope ratios (δ18O) obtained from the top 16 mm of a stalagmite collected from Wanxiang Cave,Wudu,Gansu,variation of monsoonal precipita-tion in the modern Asian Monsoon (AM) marginal zone over the past 100 years was reconstructed. Comparison of the speleothem δ18O record with instrumental precipitation data at Wudu in the past 50 years indicates a high parallelism between the two curves,suggesting that the speleothem δ18O is a good proxy for the AM strength and associated precipitation,controlled by "amount effect" of the pre-cipitation. Variation of the monsoonal precipitation during the past 100 years can be divided into three stages,increasing from AD 1875 to 1900,then decreasing from AD 1901 to 1946,and increasing again thereafter. This variation is quite similar to that of the Drought/Flooding index archived from Chinese historical documents. This speleothem-derived AM record shows a close association with the Pacific Decadal Oscillation (PDO) between AD 1875 and 1977,with higher monsoonal precipitation corre-sponding to cold PDO phase and vice versa at decadal timescale. The monsoonal precipitation varia-tion is out of phase with the PDO after AD 1977,probably resulting from the decadal climate jump in the north Pacific occurring at around AD 1976/77. These results demonstrate a strong linkage between the AM and associated precipitation and the Pacific Ocean via ocean/atmosphere interaction. This rela-tionship will aid to forecast future hydrological cycle for the AM monsoon region,and to improve forecasting potential of climatic model with observation data from cave.

关键词：石笋同位素季风降水

Reconfigurable metasurface-based 1×2 waveguide switch

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Photonics Research 2021年第10期9卷 2104-2115页

作者： AMGED ALQULIAH MOHAMED ELKABBASH JINLUO cheng GOPAL VERMA CHAUDRY SAJED SARAJ WEI LI chunlei GUO GPL Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China University of Chinese Academy of Sciences Beijing 100049China The Institute of Optics University of RochesterRochesterNew York 14627USA Current address:The Research Laboratory of Electronics Massachusetts Institute of TechnologyCambridgeMassachusetts 02139USA

Reconfigurable nanophotonic components are essential elements in realizing complex and highly integrated photonic *** we report a novel concept for devices with functionality to dynamically control guided light in the near-visible spectral range,which is illustrated by a reconfigurable and non-volatile(1×2)switch using an ultracompact active *** switch is made of two sets of nanorod arrays of TiO_(2) and antimony trisulfide(Sb_(2)S_(3)),a low-loss phase-change material(PCM),patterned on a silicon nitride *** metasurface creates an effective multimode interferometer that forms an image of the input mode at the end of the stem waveguide and routes this image toward one of the output ports depending on the phase of PCM ***,our metasurface-based 1×2 switch enjoys an ultracompact coupling length of 5.5μm and a record high bandwidth(22.6 THz)compared to other PCM-based ***,our device exhibits low losses in the near-visible region(∼1 dB)and low cross talk(−11.24 dB)over a wide bandwidth(22.6 THz).Our pro-posed device paves the way toward realizing compact and efficient waveguide routers and switches for applications in quantum computing,neuromorphic photonic networking,and biomedical sensing and optogenetics.

关键词： waveguide interferometer surface

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云南苍山种子植物新记录(二)

西部林业科学 2024年第5期53卷 40-48,63页

作者：陈罡钱美琳白蕊珠麻利岗马建伟杨思琪赵勇曾成柴勇武力张路斌彭华向春雷马小磊西南林业大学林学院云南昆明650224 中国科学院昆明植物研究所植物化学与天然药物重点实验室云南昆明650201 苍山洱海国家级自然保护区管理局漾濞县苍山分局云南漾濞672500 苍山洱海国家级自然保护区管理局大理市苍山分局云南大理671000 苍山洱海国家级自然保护区管理局洱源县苍山分局云南洱源671200 昆明市濒危动植物收容拯救中心云南昆明650224 云南省林业和草原科学院云南昆明650201

为全面澄清云南苍山的植物多样性,于2023年9月至2024年8月通过野外标本采集、鉴定与资料整理,在前文报道了100个种子植物新记录种的基础上,再继续报道该区110个种子植物新记录种。其隶属于48科94属,含1个云南省新记录种(短柄筒距兰)、4... 详细信息

为全面澄清云南苍山的植物多样性,于2023年9月至2024年8月通过野外标本采集、鉴定与资料整理,在前文报道了100个种子植物新记录种的基础上,再继续报道该区110个种子植物新记录种。其隶属于48科94属,含1个云南省新记录种(短柄筒距兰)、4个国家重点保护野生植物(杜鹃兰、艳花独蒜兰、云龙重楼、川桑)和1个云南省重点保护野生植物(小尖囊兰)。这些新记录物种的发现,对丰富苍山植物区系及植物资源保护与利用的研究具有重要意义。

关键词：植物多样性植物区系新记录种苍山种子植物

Young Leaf White Stripe encodes a P-type PPR protein required for chloroplast development

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Journal of Integrative Plant Biology 2023年第7期65卷 1687-1702页

作者： Jie Lan Qibing Lin chunlei Zhou Xi Liu Rong Miao Tengfei Ma Yaping Chen Changling Mou Ruonan Jing Miao Feng Thanhliem Nguyen Yulong Ren Zhijun cheng Xin Zhang Shijia Liu Ling Jiang Jianmin Wan State Key Laboratory of Crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research CenterNanjing Agricultural UniversityNanjing 210095China National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop ScienceChinese Academy of Agricultural SciencesBeijing 100081China

Pentatricopeptide repeat(PPR) proteins function in post-transcriptional regulation of organellar gene expression. Although several PPR proteins are known to function in chloroplast development in rice(Oryza sativa), the detailed molecular functions of many PPR proteins remain ***, we characterized a rice young leaf white stripe(ylws) mutant, which has defective chloroplast development during early seedling ***-based cloning revealed that YLWS encodes a novel P-type chloroplast-targeted PPR protein with 11 PPR motifs. Further expression analyses showed that many nuclear-and plastid-encoded genes in the ylws mutant were significantly changed at the RNA and protein levels. The ylws mutant was impaired in chloroplast ribosome biogenesis and chloroplast development under low-temperature conditions. The ylws mutation causes defects in the splicing of atpF, ndhA, rpl2,and rps12, and editing of ndhA, ndhB, and rps14transcripts. YLWS directly binds to specific sites in the atpF, ndhA, and rpl2 pre-mRNAs. Our results suggest that YLWS participates in chloroplast RNA group II intron splicing and plays an important role in chloroplast development during early leaf development.

关键词： chloroplast development PPR protein ribosome biogenesis RNA splicing