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Damping and power spectra of quasi-periodic intensity disturbances above a solar polar coronal hole

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Research in Astronomy and Astrophysics 2016年第6期16卷 85-92页

作者： Fang-ran jiao Li-Dong Xia Zheng-Hua Huang Bo Li Hui Fu Ding Yuan Kalugodu Chandrashekhar Shandong Provincial key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space Sciences Shandong University Weihai 264209 Shandong China Jeremiah Horrocks Institute University of Central Lancashire Preston PR1 2HE UK

We study intensity disturbances above a solar polar coronal hole that can be seen in the AIA 171 and 193 ＆ passbands, aiming to provide more insights into their physical nature. The damping and power spectra of the intensity disturbances with frequencies from 0.07 mHz to 10.5 mHz are investigated. The damping of the intensity disturbances tends to be stronger at lower frequencies, and their damping behavior below 980＂（for comparison, the limb is at 945＂） is different from what happens above. No significant difference is found between the damping of the intensity disturbances in the AIA 171 ~ and that in the AIA 193 ]k. The indices of the power spectra of the intensity disturbances are found to be slightly smaller in the AIA 171/~ than in the AIA 193 ~, but the difference is within one standard deviation. An additional enhanced component is present in the power spectra in a period range of 8-40 min at lower heights. The power spectra of a spicule is highly correlated with its associated intensity disturbance, which suggests that the power spectra of the intensity disturbances might be a mixture of spicules and wave activities. We suggest that each intensity disturbance in the polar coronal hole is possibly a series of independent slow magnetoacoustic waves triggered by spicular activities.

关键词： Sun: corona- Sun: waves -- Sun: turbulence -- method: observational

Collective rotations of fission isomers in actinide nuclei

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Science China(Physics,Mechanics & Astronomy) 2014年第2期57卷 189-193页

作者： XIE kePing ke WeiYao LIANG WuYang FU XiMing jiao ChangFeng PEI JunChen XU FuRong School of Physics Peking University State key Laboratory of Nuclear Physics and Technology School of PhysicsPeking University National Institute for Radiological Protection Chinese Center for Disease Control and Prevention

Using the total-Routhian-surface （TRS） method, the rotational behaviors of fission isomers in the second well of actinide nuclei 234-242U, 236-244pu and 238-246Cm were investigated. The pairing-deformation-frequency self-consistent TRS calculations repro- duced reasonably the experimental moments of inertia extracted from spectroscopic data. It is calculated that, in these largely elongated （β2 ≈0.65 and β4≈ 0.03） fission isomers, the ν1/2-[981] neutron and π1/2＋[651] proton align simultaneously at rotational frequency hω≈0.4 - 0.6 MeV （corresponding to spin I≈80h）, which leads to clear upbending in moments of inertia （MoI＇s）. Our calculations have indicated that the hexadecapole deformation f14 influenced significantly the frequency of the rotational alignment of the proton 1/2＋[651] orbit.

关键词： fission isomers total Routhian surface moments of inertia upbending alignment

Ligand-binding properties of three odorant-binding proteins of the diamondback moth Plutella xylostella

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Journal of Integrative Agriculture 2016年第3期15卷 580-590页

作者： ZHU jiao Paolo Pelosi LIU Yang LIN ke-jian YUAN Hai-bin WANG Gui-rong College of Agriculture Jilin Agricutural University State key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences

Strategies for insect population control are currently targeting chemical communication at the molecular level. The diamondback moth Plutella xylostella represents one of the most serious pests in agriculture, however detailed information on the proteins mediating olfaction in this species is still poor. This species is endowed with a repertoire of a large number of olfactory receptors and odorant binding proteins（OBPs）. As a contribution to map the specificities of these chemical sensors in the moth and eventually unrave l the complexity of chemodetection, we have measured the affinities of three selected OBPs to a series of potential odorants. Three proteins are highly divergent in their amino acid sequences and show markedly different expression profiles. In fact, PxylOBP3 is exclusively expressed in the antennae of both sexes, PxylOBP9 is male specific and present only in antennae and reproductive organs, while PxylOBP19, an unusual OBP with nine cysteines, is ubiquitously present in all the organs examined. Such expression pattern suggests that the last two proteins may be involved in non-chemosensory functions. Despite such differences, the three OBPs exhibit similar binding spectra, together with high selectivity. Among the 26 natural compounds tested, only two proved to be good ligands, retinol and coniferyl aldehyde. This second compound is particularly interesting being part of the chemical pathway leading to regeneration of lignin, one of the defense strategies of the plant against insect attack, and might find applications as a repellent for P. xylostella and other pests.

关键词： odorant-binding protein Plutella xylostella ligand-binding tryptophan quenchin molecular docking

基于SAS算法的起飞一发失效应急路径规划方法

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航空学报 2016年第10期37卷 3140-3148页

作者：焦卫东程颖柯然中国民航大学天津市智能信号与图像处理重点实验室天津300300 中国农业银行科技部上海200000

为解决起飞一发失效应急程序(EOSID)手动设计的不足,提出一种基于SRTM数据的稀疏A*搜索(SAS)算法的EOSID路径规划方法。首先采用航天飞机雷达地形测绘使命(SRTM)的网格地形数据,结合起飞一发失效相关规章,考虑爬升梯度与保护区限制确定... 详细信息

为解决起飞一发失效应急程序(EOSID)手动设计的不足,提出一种基于SRTM数据的稀疏A*搜索(SAS)算法的EOSID路径规划方法。首先采用航天飞机雷达地形测绘使命(SRTM)的网格地形数据,结合起飞一发失效相关规章,考虑爬升梯度与保护区限制确定可行搜索空间;然后基于可行搜索空间运用稀疏A*搜索算法搜索应急离场路径,在传统A*算法寻找扩展节点时加入起飞性能约束条件,同时利用地形高程数据进行地形和威胁回避,生成一条三维应急离场航迹;最后利用三次样条曲线对规划的应急离场航迹进行平滑处理。实验结果表明该方法能自动搜索出有效的EOSID三维航迹。

关键词： EOSID 航迹规划稀疏A*算法起飞性能三次样条曲线

Dynamics of Haptophytes(Eukaryota,Hacrobia)Revealed via Short-Term Sampling in the South China Sea

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Journal of Ocean University of China 2024年第6期23卷 1677-1688页

作者： ZHANG Haoyue LI ran GU Bowei KONG Hejun XU Jie ZHANG Rui LI Xiaolin jiao Nianzhi XU Dapeng College of Ocean and Earth Sciences State Key Laboratory of Marine Environmental ScienceXiamen UniversityXiamen 361102China Institute of Marine Microbes and Ecospheres Fujian Key Laboratory of Marine Carbon SequestrationXiamen UniversityXiamen 361102China Centre for Regional Oceans Department of Ocean Science and TechnologyFaculty of Science and TechnologyUniversity of MacaoMacao 999078China Institute for Advanced Study Shenzhen UniversityShenzhen 518060China

Haptophytes(Eukaryota,Hacrobia)play a crucial role in the energy budget and element cycling of diverse aquatic ecosystems due to their ability to engage in both phototrophic and mixotrophic nutritional ***,there is a significant lack of knowledge regarding the short-term variations,such as diel dynamics,of their ecological *** a short time frame in the summer of 2018,samples were collected from three distinct water layers in the South China Sea,including surface water,the deep chlorophyll maximum(DCM)layer,and 200 m *** in situ hybridization coupled with tyramide signal amplification was used to quantify haptophyte cell *** haptophyte communities in all three water layers were composed of cells 2-5μm in size,while the proportion of cells<2μm increased with water ***-throughput sequencing of the V4 hypervariable regions of the SSU rRNA revealed that Chrysochromulina and Phaeocystis predominated the community,and the former was more abundant in the surface water and 200 m depth and the latter was more abundant in the DCM *** abundance of small cells(<2μm and 2-5μm)during the night was found compared to the day time,whereas large cells(5-10μm and 10-20μm)were more prevalent during the day *** results of correlation analyses showed that haptophyte abundance was possibly impacted by both environmental biotic(heterotrophic nanoflagellates,heterotrophic bacteria,and viruses)and abiotic(temperature,salinity,and nutrients)factors.

关键词： eukaryotic phytoplankton FISH-TSA high-throughput sequencing microbial eukaryotes size fraction

Revealing climatic impacts on the temporal and spatial variation in vegetation activity across China:Sensitivity and contribution

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Advances in Climate Change Research 2021年第3期12卷 409-420页

作者： jiao ke-Wei GAO Jiang-Bo LIU Zhi-Hua WU Shao-Hong Tamara L.FLETCHER key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang110016China key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China

Relative weakness in sensitivity and contribution integration,especially lack of specific indicators at spatial and temporal scales,may hinder the formation of systematic knowledge for climate change impact on vegetation *** the interannual variability and periods difference,we investigated the ecosystem sensitivity to hydrothermal conditions and the contribution of individual climatic factors to vegetation activity on spatiotemporal scales during the period of 1980s—2013 in *** ran simulations of the Common Land Model(CoLM)to obtain the photosynthetic rate,and used the satellite-derived Normalized Difference Vegetation Index(NDVI),to which we applied a temporal sensitivity analysis,the slope change ratio of accumulative quantity(SCRAQ),and geographical *** show that the discrepancy between warming and precipitation variation contributed to vegetation activity was more notable than the ecosystem sensitivity to hydrothermal conditions,regardless of which temporal and spatial scale was *** sensitivity of vegetation activity to hydrothermal variation in most parts of northeastern and western China was higher than elsewhere,and the contribution of warming to vegetation dynamics was relatively high in the Inner Mongolian Plateau and Tibetan Plateau(>60%),where the contribution of warming to the vegetation distribution was also greater than elsewhere in ***,the contribution of precipitation variation to vegetation dynamics was comparatively greater in northwestern China and subtropical and tropical regions(>55%).The spatiotemporal contribution of precipitation variation to vegetation activity differed between regions,especially on the Tibetan Plateau and in subtropical and tropical ***,both the temporal and spatial sensitivities to climate change were weak in the subtropical and tropical regions,where the contribution of climatic factors to vegetation distribution was also ***,temperature sensit

关键词： Vegetation activity Climate change Sensitivity Contribution Spatial-temporal scales China

使用合规农药能确保农产品“地头”质量安全吗?——基于豇豆农户的扎根理论分析

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海南大学学报（人文社会科学版） 2025年第1期43卷 119-128页

作者：樊孝凤张娇朱月季海南大学国际商学院海南海口570228

新的农产品质量安全法首次将小农户施药行为纳入监管范围,进一步厘清农户施药行为的影响机理与因素,有助于政府精准施策。通过对海南3个村32户农民豇豆种植过程的全程蹲点跟踪,对豇豆施药环节的参与式观察与深度访谈,运用扎根理论分析... 详细信息

新的农产品质量安全法首次将小农户施药行为纳入监管范围,进一步厘清农户施药行为的影响机理与因素,有助于政府精准施策。通过对海南3个村32户农民豇豆种植过程的全程蹲点跟踪,对豇豆施药环节的参与式观察与深度访谈,运用扎根理论分析了访谈资料。研究发现:农户施药环节是一个复杂的行为选择过程,即使施用合规农药也不能确保农产品在产地的质量安全。在合规农药视角下影响农户施药行为选择的最重要因素是信息渠道,其次是农产品质量安全管理的政策强度、农产品市场价格和农村劳动用工成本。同时,邻里效应在农户施药行为选择中的作用越来越弱。在此基础上提出,要增加农户用药信息的有效供给渠道,加强农产品质量安全的全面检测,坚持为农户提供形式多样的有针对性的有效培训,增加重要食用农产品质量安全关键技术供给与推广,加强农产品“优质优价”市场建设的政策建议,并进一步指出海南自贸港建设和RECP协议实施背景下提升海南农产品质量安全水平的紧迫性。

关键词：合规农药施药行为农产品质量安全扎根理论

Two sandwich-type uranyl-containing polytungstates catalyze aerobic synthesis of benzimidazoles

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Rare Metals 2024年第3期43卷 1316-1322页

作者： Yu-Feng Liu Qi-Long Hu Xue-jiao Chen ke Li Pei Luo Guo-Ping Yang School of Chemistry and Material Science Jiangxi Province Key Laboratory of Synthetic ChemistryJiangxi Key Laboratory for Mass Spectrometry and InstrumentationEast China University of TechnologyNanchang330013China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen518055China

Diversified synthetic strategies are extremely important for the structural diversity of uranium-containing polyoxometalates(U-POMs)and their functional ***,two sandwich-type U-POMs were reported,which are Na_(5.6)K_(6.4)[(UO_(2))(H_(2)O)(TeW_(9)O_(33))]_(2)·21H_(2)O(UTeW_(9))and Na_(8.9)K_(2.7)H_(1.19)[K_(0.79)(UO_(2))_(2.21)(PW_(9)O_(34))_(2)]·12H_(2)O(UPW_9)using in-situ strategy and lacunary precursor strategy,***_9 shows a typical keggin-typeopen or half-sandwich configuration.

关键词： configuration expansion sandwich

New clinical trial design in precision medicine:discovery,development and direction

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1293-1321页

作者： Xiao-Peng Duan Bao-Dong Qin Xiao-Dong jiao ke Liu Zhan Wang Yuan-Sheng Zang Department of Medical Oncology Changzheng HospitalNaval Medical UniversityShanghaiChina

In the era of precision medicine,it has been increasingly recognized that individuals with a certain disease are complex and different from each *** to the underestimation of the significant heterogeneity across participants in traditional"one-sizefits-all"trials,patient-centered trials that could provide optimal therapy customization to individuals with specific biomarkers were developed including the basket,umbrella,and platform trial designs under the master protocol *** recent years,the successive FDA approval of indications based on biomarker-guided master protocol designs has demonstrated that these new clinical trials are ushering in tremendous *** the rapid increase in the number of basket,umbrella,and platform trials,the current clinical and research understanding of these new trial designs,as compared with traditional trial designs,remains *** majority of the research focuses on methodologies,and there is a lack of in-depth insight concerning the underlying biological logic of these new clinical trial ***,we provide this comprehensive review of the discovery and development of basket,umbrella,and platform trials and their underlying logic from the perspective of precision ***,we discuss future directions on the potential development of these new clinical design in view of the"Precision Pro","Dynamic Precision",and"Intelligent Precision".This review would assist trial-related researchers to enhance the innovation and feasibility of clinical trial designs by expounding the underlying logic,which be essential to accelerate the progression of precision medicine.

关键词： clinical approval successive