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Suzuki Coupling Reaction Catalyzed by Cyclopalladated Complexes of Tertiary Arylamines in Ionic Liquid

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Chinese Chemical Letters 2005年第9期16卷 1173-1176页

作者： hua yi Jin Biao LIU Qiang LI Jie TANG Department of Chemistry East China Normal University Shanghai 200062

Suzuki cross-coupling reaction of phenylboronic acid with aryl halides catalyzed by cyclopalladated complexes of tertiary arylamines immobilized in ionic liquid [Bmim]^＋BF4^- was reported. The catalytic system proved... 详细信息

关键词： Cyclopalladated complex aryl halides Suzuki coupling biaryl ionic liquid

The importance of source positions during radio fine structure observations

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Research in Astronomy and Astrophysics 2014年第7期14卷 831-842页

作者： Guennadi P.Chernov yi-hua Yan Qi-Jun Fu Key Laboratory of Solar Activity National Astronomical ObservatoryChinese Academy of Sciences Pushkov Institute of Terrestrial Magnetism Ionosphere and Radio Wave PropagationRussian Academy of Sciences (IZMIRAN)TroitskMoscow region142190Russia

The measurement of positions and sizes of radio sources in the observations of the fine structure of solar radio bursts is a determining factor for the selection of the radio emission mechanism. The identical parameters describing the radio sources for zebra structures（ZSs） and fiber bursts confirm there is a common mechanism for both structures. It is very important to measure the size of the source in the corona to determine if it is distributed along the height or if it is point-like. In both models of ZSs（the double plasma resonance（DPR） and the whistler model） the source must be distributed along the height, but by contrast to the stationary source in the DPR model, in the whistler model the source should be moving. Moreover, the direction of the space drift of the radio source must correlate with the frequency drift of stripes in the dynamic spectrum. Some models of ZSs require a local source, for example,the models based on the Bernstein modes, or on explosive instability. The selection of the radio emission mechanism for fast broadband pulsations with millisecond duration also depends on the parameters of their radio sources.

关键词： solar flare -- radio emission -- zebra-pattern -- spike-bursts

DSC based Dual-Resunet for radio frequency interference identification

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Research in Astronomy and Astrophysics 2021年第12期21卷 315-325页

作者： Yan-Jun Zhang Yan-Zuo Li Jun Cheng yi-hua Yan School of Cyberspace Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China CAS Key Laboratory of Solar Activity National Astronomical ObservatoriesBeijing 100101China State Key Laboratory of Space Weather Chinese Academy of SciencesBeijing 100864China

Radio frequency interference(RFI)will pollute the weak astronomical signals received by radio telescopes,which in return will seriously affect the time-domain astronomical observation and *** this paper,we use a deep learning method to identify RFI in frequency spectrum data,and propose a neural network based on Unet that combines the principles of depthwise separable convolution and residual,named DSC Based *** with the existing Unet network,DSC Based Dual-Resunet performs better in terms of accuracy,F1 score,and MIoU,and is also better in terms of computation cost where the model size and parameter amount are 12.5%of Unet and the amount of computation is 38%of *** experimental results show that the proposed network is a high-performance and lightweight network,and it is hopeful to be applied to RFI identification of radio telescopes on a large scale.

关键词： techniques:deep learning and image processing radio frequency interference telescopes Sun:radio radiation

Role of permafrost in resilience of social-ecological system and its spatio-temporal dynamics in the source regions of Yangtze and Yellow Rivers

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Journal of Mountain Science 2019年第1期16卷 179-194页

作者： FANG yi-ping ZHU Fu-biao yi Shu-hua QIU Xiao-ping DING Yong-jian Institute of Mountain Hazards and Environment Chinese Academy of Sciences College of Resource and Environment University of Chinese Academy of Sciences School of Economics Hefei University of Technology School of Geographic Sciences Nantong University College of Geography and Resources Science Sichuan Normal University State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences

Permafrost is one of the key components of terrestrial ecosystem in cold regions. In the context of climate change, few studies have investigated resilience of social ecological system(SER) from the perspective of permafrost that restricts the hydrothermal condition of alpine grassland ecosystem. In this paper, based on the structural dynamics, we developed the numerical model for the SER in the permafrost regions of the source of Yangtze and Yellow Rivers, analyzed the spatial-temporal characteristics and sensitivity of the SER, and estimated the effect of permafrost change on the SER. The results indicate that: 1) the SER has an increasing trend, especially after 1997, which is the joint effect of precipitation, temperature, NPP and ecological conservation projects; 2) the SER shows the spatial feature of high in southeast and low in northwest,which is consistent with the variation trends of high southeast and low northwest for the precipitation, temperature and NPP, and low southeast and high northwest for the altitude; 3) the high sensitive regions of SER to the permafrost change have gradually transited from the island distribution to zonal and planar distribution since 1980, moreover, the sensitive degree has gradually reduced; relatively, the sensitivity has high value in the north and south, and low value in the south and east; 4) the thickness of permafrost active layer shows a highly negative correlation with the SER. The contribution rate of permafrost change to the SER is-4.3%, that is, once the thickness of permafrost active layer increases 1 unit, the SER would decrease 0.04 units.

关键词： Resilience of social ecological system Permafrost Permafrost active layer thickness Structural dynamic equation Source regions of Yangtze and Yellow rivers

Solar image deconvolution by generative adversarial network

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Research in Astronomy and Astrophysics 2020年第11期20卷 182-190页

作者： Long Xu Wen-Qing Sun yi-hua Yan Wei-Qiang Zhang Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China College of Mathematics and Statistics Shenzhen UniversityShenzhen 518060China

With aperture synthesis(AS)technique,a number of small antennas can be assembled to form a large telescope whose spatial resolution is determined by the distance of two farthest antennas instead of the diameter of a single-dish *** contrast from a direct imaging system,an AS telescope captures the Fourier coefficients of a spatial object,and then implement inverse Fourier transform to reconstruct the spatial *** to the limited number of antennas,the Fourier coefficients are extremely sparse in practice,resulting in a very blurry *** remove/reduce blur,“CLEAN”deconvolution has been widely used in the ***,it was initially designed for a point *** an extended source,like the Sun,its efficiency is *** this study,a deep neural network,referring to Generative Adversarial Network(GAN),is proposed for solar image *** experimental results demonstrate that the proposed model is markedly better than traditional CLEAN on solar *** main purpose of this work is visual inspection instead of quantitative scientific *** believe that this will also help scientists to better understand solar phenomena with high quality images.

关键词： deep learning(DL)generative adversarial network(GAN)solar radio astronomy

A new triterpene glycoside from sea cucumber Holothuria leucospilota

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Chinese Chemical Letters 2007年第2期18卷 161-164页

作者： hua Han Yang hua yi Ling Li Xiao hua Wang Bao Shu Liu Peng Sun Min Xiang Pan Research Center for Marine Drugs School of Pharmacy Second Military Medical University Shanghai 200433 China

A new triterpene glycoside, leucospilotaside A, along with a known saponin, isolated from sea cucumber Holothuria leucospilota, and its structure was elucidated as 3β-O-[4-O-sodiumsulfate-β-d-quinovopyranosyl-(1 → 2)-β-d-xylopyranosyl]-holosta-22-ketone-9-en-17α,25α-diol (1) by extensive spectroscopic analysis and chemical methods. Leucospilotaside A (1) has a ketone carbonyl group (22) in the aglycon side chain.

关键词： Sea cucumber Holothuria leucospilota Triterpene glycoside Leucospilotaside A

Two novel sodium channel mutations associated with resistance to indoxacarb and metaflumizone in the diamondback moth, Plutella xylostella

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Insect Science 2016年第1期23卷 50-58页

作者： Xing-Liang Wang Wen Su Jian-Heng Zhang yi-hua Yang Ke Dong yi-Dong Wu College ofPlantProtection NanjingAgricultural University Nanjing China Department of Entomology Genetics and Neuroscience Programs Michigan State University East Lansing MI USA

Indoxacarb and metaflumizone belong to a relatively new class of sodium channel blocker insecticides （SCBIs）. Due to intensive use of indoxacarb, field-evolved indoxacarb resistance has been reported in several lepidopteran pests, including the dia- mondback moth Plutella xylostella, a serious pest of cruciferous crops. In particular, the BY 12 population of P. xylostella, collected from Baiyun, Guangdong Province of China in 2012, was 750-fold more resistant to indoxacarb and 70-fold more resistant to metaflu- mizone compared with the susceptible Roth strain. Comparison of complementary DNA sequences encoding the sodium channel genes of Roth and BY12 revealed two point mu- tations （F1845Y and V1848I） in the sixth segment of domain IV of the PxNav protein in the BY population. Both mutations are located within a highly conserved sequence region that is predicted to be involved in the binding sites of local anesthetics and SCBIs based on mammalian sodium channels. A significant correlation was observed among 10 field-collected populations between the mutant allele （Y 1845 or I 1848） frequencies （1.7% to 52.5%） and resistance levels to both indoxacarb （34- to 870-fold） and metaflumizone （1- to 70-fold）. The two mutations were never found to co-exist in the same allele of PxNav, suggesting that they arose independently. This is the first time that sodium channel muta- tions have been associated with high levels of resistance to SCBIs. F 1845Y and V 1848I are molecular markers for resistance monitoring in the diamondback moth and possibly other insect pest species.

关键词： indoxacarb metaflumizone mutation Plutellaxylostella resistance sodium channel

A novel protease-activated receptor 1 inhibitor from the leech Whitmania pigra

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Chinese Journal of Natural Medicines 2019年第8期17卷 591-599页

作者： REN Shen-Hong LIU Zhao-Jun CAO Yuan hua yi CHEN Cong GUO Wei KONG yi School of Life Science & Technology China Pharmaceutical University Nanjing 210009 China School of Life Science China Pharmaceutical University Nanjing 210009 China Jiangsu Province Hospital of Chinese Medicine Affiliated Hospital of Nanjing University of Chinese Medicine Nanjing 210029 China

Whitmania pigra has been used as a traditional Chinese medicine(TCM) for promoting blood circulation, alleviating blood coagulation, activating meridians and relieving stasis for several hundred years. However, the therapeutic components of this species, especially proteins and peptides were poorly exploited. Until now only a few of them were obtained by using chromatographic isolation and purification. In recent decade, transcriptome techniques were rapidly developed, and have been used to fully reveal the functional components of many animal venoms. In the present study, the c DNA of the salivary gland of Whitmania pigra was sequenced by illumina and the transcriptome was assembled by using Trinity. The proteome were analysed by LC-MS/MS. Based on the data of the transcriptome and the proteome, a potential antiplatelet protein named pigrin was found. Pigrin was cloned and expressed using P. pastoris GS115. The antiplatelet and antithrombotic bioactivities of pigrin were tested by using aggregometer and the rat arterio-venous shunt thrombosis model, respectively. The bleeding time of pigrin was measured by a mice tail cutting method. The docking of pigrin and protease-activated receptor 1(PAR1) or collagen were conducted using the ZDOCK Server. Pigrin was able to selectively inhibit platelet aggregation stimulated by PAR1 agonist and collagen. Pigrin attenuated thrombotic formation in vivo in rat, while did not prolong bleeding time at its effective dosage. There are significant differences in the key residues participating in binding of Pigrin-Collagen complex from Pigrin-PAR1 complex. In conclusion, a novel PAR1 inhibitor pigrin was found from the leech Whitmania pigra. This study helped to elucidate the mechanism of the leech for the treatment of cardiovascular disorder.

关键词： Whitmania pigra Transcriptome and proteome PAR1 inhibitor Thrombosis

Morphogenesis of Pistillate Flowers of Cercidiphyllum japonicum(Cercidiphyllaceae)

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Journal of Integrative Plant Biology 2007年第9期49卷 1400-1408页

作者： Xiao-Ling Yan yi Ren Xian-hua Tian Xiao-Hui Zhang College of Life Sciences Shaanxi Normal University Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education Xi'an 710062 China

Floral morphogenesis and the development of Cercidiphyllumjaponicum Sieb. et Zucc. were observed by scanning electron microscopy （SEM）. The results showed that the pistillate inflorescences were congested spikes with the flowers arranged opposite. Great differences between the so-called ＂bract＂ and the vegetative leaf were observed both in morphogenesis and morphology. In morphogenesis, the ＂bract＂ primordium is crescent-shaped, truncated at the apex and not conduplicate, has no stipule primordium at the base but does have some inconspicuous teeth in the margin that are not glandular. The leaf primordium is triangular, cycloidal at the apex, conduplicate, has two stipule primordia at the base, has one gland-tooth at the apex occurring at first and some gland-teeth in the margin that occur later. In morphology, the ＂bract＂ is also different to the vegetative leaf in some characteristics that were also illustrated in the present paper. Based on the hypothesis that the bract is more similar to the vegetative leaf than the tepal, we considered that the so-called ＂bract＂ of *** might be the tepal of the pistillate flower in morphological nature. Therefore, each pistillate flower contains a tepal and a carpel. We did not find any trace of other floral organs in the morphogenesis of the pistillate flower. Therefore we considered that the unicarpellate status of extant Cercidiphyllum might be to highly reduce and advance characteristics that make the extant Cercidiphyllum isolated from both fossil Cercidiphyllum-like plants and its extant affinities.

关键词： Cercidiphyllumjaponicum leaf morphogenesis pistillate flower tepal.