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Peculiarity of transcriptional and H3K27me3 dynamics during peach bud dormancy

Horticultural Plant Journal 2024年第1期10卷 38-50页

作者： Yalin Zhao yong Li ke Cao Weichao Fang Changwen Chen Xinwei Wang Jinlong Wu Wenwu Guo Lirong Wang The key Laboratory of Biology and Genetic Improvement of Horticultural Crops(Fruit Tree Breeding Technology) Ministry of AgricultureZhengzhou Fruit Research InstituteChinese Academy of Agricultural SciencesZhengzhouHenan 450009China Western Research Institute Chinese Academy of Agricultural SciencesChangjiXinjiang 831100China College of Horticulture and Forestry Science Huazhong Agricultural UniversityWuhanHubei 430070China

Bud dormancy facilitates the survival of meristems under harsh environmental *** elucidate how molecular responses to chilling accumulation controlling dormancy in peach buds,chromatin immunoprecipitation sequencing to identify the H3K27me3 modifications and RNA sequencing of two peach cultivars with pronounced differences in chilling requirement were carried out,the results showed that genes associated with abscisic acid and gibberellic acid signal pathways play key roles in dormancy *** results demonstrated that peach flower bud differentiation occurred continuously in both cultivars during chilling accumulation,which was correlated with the transcript abundance of key genes involved in phytohormone metabolism and flower bud development under adverse *** more increased strength in high chillingrequirement cultivar along with the chilling accumulation at the genome-wide *** function of the dormancy-associated MADS-box gene PpDAM6 was identified,which is involved in leaf bud break in peach and flower development in transgenic Nicotiana tabacum(NC89).In addition,PpDAM6 was positively regulated by PpCBF,and the genes of putative dormancy-related and associated with metabolic pathways were *** together,these results constituted a theoretical basis for elucidating the regulation of peach bud dormancy transition.

关键词： Peach bud Dormancy RNA-seq H3K27me3 Chilling requirement

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Simulation study on cuttings transport of the backreaming operation for long horizontal section wells

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Petroleum Science 2024年第2期21卷 1149-1170页

作者： Yu-Fei Chen Hui Zhang Wen-Xin Wu Jun Li yong Ouyang Zong-Yu Lu De-Xin Ma yong-Chuan Wu Jun-Bo Liu ke-Rou Liu Zhuo-Xin Dong China University of Petroleum(Beijing) Beijing102249China Beijing Normal University at Zhuhai Experimental and Practical Education Innovation CenterZhuhai519087GuangdongChina Oil&Gas Technology Research Institute of PetroChina Changqing Oilfield Company Xi'an710016ShaanxiChina PetroChina Xinjiang Oilfield Company Karamay834002XinjiangChina China Oilfield Services Ltd. Tianjin300459China

The backreaming operation plays a significant role in safe drilling for horizontal wellbores, while it may cause severe stuck pipe accidents. To lower the risk of the stuck pipe in backreaming operations, the mechanism of cuttings transport needs to be carefully investigated. In this research, a transient cuttings transport with multiple flow patterns model is developed to predict the evolution of cuttings transported in the annulus while backreaming. The established model can provide predictions of the distribution of cuttings bed along the wellbore considering the bulldozer effect caused by large-size drilling tools(LSDTs). The sensitivity analyses of the size of LSDTs, and backreaming operating parameters are conducted in Section 4. And a new theory is proposed to explain the mechanism of cuttings transport in the backreaming operation, in which both the bit and LSDTs have the “cleaning effect” and “plugging effect”.The results demonstrate that the cuttings bed in annuli is in a state of dynamic equilibrium, but the overall trend and the distribution pattern are obvious. First, larger diameters and longer drilling tools could lead to a higher risk of the stuck pipe. Second, we find that it is not the case that the higher flow rate is always better for hole cleaning, so three flow-rate intervals are discussed separately under the given conditions. When the “dangerous flow rate”(35 L/s in Case 4),the higher the flow rate, the better the cleaning effect of cuttings beds. Third, an interval of tripping velocity called “dangerous velocity” is proposed, in which the cuttings bed accumulation near the LSDTs is more serious than

关键词： Backreaming Stuck pipe Hole cleaning Transient solid transport Multiple flow patterns

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First wetland mapping at 10-m spatial resolution in South America using multi-source and multi-feature remote sensing data

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Science China Earth Sciences 2024年第10期67卷 3252-3269页

作者： Weiwei SUN Gang YANG Yuling HUANG Dehua MAO ke HUANG Lin ZHU Xiangchao MENG Tian FENG Chao CHEN yong GE Department of Geography and Spatial Information Techniques Ningbo UniversityNingbo 315211China State key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences&Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Natural Resources and Planning Bureau Shanghai Pudong New DistrictShanghai 200100China key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China Faculty of Electrical Engineering and Computer Science Ningbo UniversityNingbo 315211China School of Geography Science and Geomatics Engineering Suzhou University of Science and TechnologySuzhou 215009China

Wetland degradation has been accelerating in recent years globally. Accurate information on the geographic distribution and categories of wetlands is essential for their conservation and management. Despite being the world′s fourth largest continent, South America has limited research on wetland mapping, and there is currently no available map that provides comprehensive information on wetland distribution and categories in the region. To address this issue, we used Sentinel-1, Sentinel-2 and SRTM data, developed a sample collection method and a wetland mapping method with a collection of multi-source features such as optical features, polarization features and shape features for South American wetlands. We produced a 10-m resolution wetland map based on the Google Earth Engine(GEE) platform. Our Level-1 wetland cover map accurately captured six wetland sub-categories with an overall accuracy of 96.24% and a kappa coefficient of 0.8649, while our Level-2 water cover map included five sub-categories with an overall accuracy of 97.23% and a kappa coefficient of0.9368. The results show that the total area of existing wetlands in South America is approximately 1,737,000 km~2, which is6.8% of the total land area. Among the ten wetland categories, shallow sea had the largest area(960,527.4 km~2), while aquaculture ponds had the smallest area 1513.6 km~2. Swamp had the second largest area(306,240.1 km~2). Brazil, Argentina,Venezuela, Bolivia, and Colombia were found to have the largest wetland areas, with Brazil and Colombia having the most diverse wetland categories. This product can serve as baseline data for subsequent monitoring, management, and conservation of South American wetlands.

关键词： Wetland mapping Google Earth Engine Sentinel imagery South America

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Oxygen-vacancy-rich MnO_(x)supported RuO_(x)for efficient base-free oxidation of 5-hydroxymethylfurfural and 5-methoxymethylfurfural to 2,5-furandicarboxylic acid

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Journal of Energy Chemistry 2024年第8期95卷 670-683,I0015页

作者： Jiali Wu Weizhen Xie Yining Zhang Xixian ke Tianyuan Li Huayu Fang yong Sun Xianhai Zeng Lu Lin Xing Tang Xiamen key Laboratory of Clean and High-valued Applications for Biomass Fujian Engineering and Research Center of Clean and High-valued Technologies for BiomassCollege of EnergyXiamen UniversityXiamen 361102FujianChina key Lab for Sport Shoes Upper Materials of Fujian Province Fujian Engineering and Research Center for New Functional Fiber Materials(Fujian Huafeng New Material Co.Ltd.Putian Dakai New Material Co.Ltd.)Putian 351144FujianChina

2,5-Furandicarboxylic acid(FDCA)is a promising biomass-derived polymeric monomer that serves as an attractive alternative to terephthalic acid derived from fossil ***,the green and efficient production of FDCA through the oxidation of 5-hydroxymethylfurfural(HMF)and its derivatives is still rudimentary under base-free *** this work,oxygen-vacancy-rich Mn Oxwas prepared and displayed a strong adsorption and anchoring ability to Ru species that mainly exposed the(210)plane of RuO_(2),bringing about highly dispersed and active interfacial Ru-O-Mn *** results and density functional theory calculations confirm that these above features greatly facilitate the adsorption/activation of oxygen and the dehydrogenation-oxidation of HMF/5-methoxymethylfurfural(MMF),which enables an efficient FDCA production under base-free and mild ***,a desirable FDCA yield of 86.56%was still obtained from concentrated HMF(10 wt%)under base-free conditions over oxygen-vacancy-rich Mn Oxsupported Ru Ox(1.0 MPaO_(2),120℃,6 h).This work delineates a facile catalyst preparation strategy for HMF/MMF oxidation,and might open a new avenue for the green synthesis of FDCA under base-free conditions.

关键词： Base-free oxidation Oxygen-vacancy-rich 5-Hydroxymethylfurfural 5-Methoxymethylfurfural 2 5-Furandicarboxylic acid

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On the faults of western Hexi Corridor and its nearby regions, northwestern China: Thrust faults and strike-slip faults of Late Cenozoic

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Acta Seismologica Sinica(English Edition) 2004年第6期17卷 662-670页

作者： HE Guang-yu YANG Shu-feng CHEN Han-lin XIAO An-cheng HAN yong-ke LI Jian-li LIU Yu GAO Jun-liang Department of Earth Sciences Zhejiang University Hangzhou 310027 China Yumen Oilfield Company China National Petroleum Corporation Yumen 735000 China Henan Oilfield Company China Petroleum and Chemical Corporation Nanyang 473132 China

The structural analysis based on the explanation of seismic profiles indicates that a lot of thrust faults and strike-slip faults of Late Cenozoic occur in western Hexi Corridor and its nearby regions. They can be divided into two types. One is thrust faults dipping southwards and extending NWwards, which was mainly correlated with the thrusting of northern Qilianshan and located at the NE margin of Qilianshan and the southwestern Hexi Corridor, the other is thrust faults and strike-slip faults that were related to the strike-slipping of Altun fault and located mainly at the regions of Hongliuxia, Kuantaishan, and Helishan that are close to the Altun fault. All these faults, which were related to the remote effects of collision between the two continents of India and Tibet during the Late Eocene and later, started to develop since the Late Tertiary and presented the features of violent thrust or strike-slip movement in Quaternary. Many of them are still active up to now and thus belong to the active faults that are the potential inducement of earthquakes in the Hexi Corridor. Moreover, a lot of intense structural deformation and many morphology phenomena such as tectonic terrace and river offset were formed under the control of these faults in Quaternary.

关键词： thrust fault strike-slip fault earthquake Hexi Corridor

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非线性散射介质内辐射传递的积分矩方法

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红外与毫米波学报 2011年第6期30卷 537-540页

作者：朱克勇黄勇姜军王浚北京航空航天大学航空科学与工程学院北京100191 北京空间技术试验中心北京100094

提出了求解非线性散射介质内辐射传递的积分矩方法.将辐射传递方程中散射相函数的积分项转化为辐射强度各阶矩的线性组合.散射相函数为勒让德多项式展开形式,辐射强度矩的最高阶数与散射相函数的展开项数相同.将原本复杂的积分微分方程... 详细信息

提出了求解非线性散射介质内辐射传递的积分矩方法.将辐射传递方程中散射相函数的积分项转化为辐射强度各阶矩的线性组合.散射相函数为勒让德多项式展开形式,辐射强度矩的最高阶数与散射相函数的展开项数相同.将原本复杂的积分微分方程转化为微分方程,通过积分法求解此方程.积分矩方法不需要对立体角进行离散,不会引起射线效应.积分矩方法的计算结果与其他数值方法符合得很好,具有很高的计算精度.同时,在较少计算网格数的条件下,仍然可以得到较为满意的结果.

关键词：辐射传递非线性散射积分矩方法

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牙周病和龋病相关性分析-基于NHANES数据库对真实世界的研究

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牙体牙髓牙周病学杂志 2024年第5期29卷 259-266页

作者：汪敏牛晨光王天娇苑克勇屠叶李好黄正蔚温州医科大学附属口腔医院牙体牙髓科浙江温州325000 上海交通大学医学院附属第九人民医院牙体牙髓科上海交通大学口腔医学院国家口腔医学中心国家口腔疾病临床医学研究中心上海市口腔医学重点实验室上海市口腔医学研究所上海200135

目的:基于真实世界数据库探讨牙周病和龋病的相关性,为疾病诊疗和健康管理提供理论依据。方法:下载2011年至2014年美国国家健康和营养调查(NHANES)数据库中牙周病和龋病状况检查数据,按照疾病严重程度有序分组,采用广义有序Logistic回... 详细信息

目的:基于真实世界数据库探讨牙周病和龋病的相关性,为疾病诊疗和健康管理提供理论依据。方法:下载2011年至2014年美国国家健康和营养调查(NHANES)数据库中牙周病和龋病状况检查数据,按照疾病严重程度有序分组,采用广义有序Logistic回归模型进行相关性分析。结果:研究共纳入参与者6299例,轻度、中度和重度牙周炎发病率分别为42.34%、28.15%和11.53%;轻度、中度和重度龋病发病率分别为19.60%、28.34%和35.61%。对于牙周炎,年龄增长、低收入水平、男性、过度饮酒、糖尿病、高血压、中重度抽烟都是加重病情的危险因素。重度龋病和牙周病加重风险升高显著相关,轻度和中度龋病无显著影响。对于龋病,高血压、女性、低收入水平、年龄增长、重度抽烟都是加重病情的危险因素。所有类型牙周病都与龋病加重风险升高显著相关。结论:牙周病和龋病关联十分紧密,它们发生发展具有彼此促进作用,牙周病对龋病病情影响更大。

关键词：牙周病龋病 NHANES数据库相关性分析疾病严重程度权重

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A quantum blind signature scheme based on dense coding for non-entangled states

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Chinese Physics B 2024年第6期33卷 220-228页

作者：邢柯殷爱菡薛勇奇 Department of Information Engineering East China Jiaotong UniversityNanchang 330013China

In some schemes, quantum blind signatures require the use of difficult-to-prepare multiparticle entangled states. By considering the communication overhead, quantum operation complexity, verification efficiency and other relevant factors in practical situations, this article proposes a non-entangled quantum blind signature scheme based on dense encoding. The information owner utilizes dense encoding and hash functions to blind the information while reducing the use of quantum resources. After receiving particles, the signer encrypts the message using a one-way function and performs a Hadamard gate operation on the selected single photon to generate the signature. Then the verifier performs a Hadamard gate inverse operation on the signature and combines it with the encoding rules to restore the message and complete the *** with some typical quantum blind signature protocols, this protocol has strong blindness in privacy protection,and higher flexibility in scalability and application. The signer can adjust the signature operation according to the actual situation, which greatly simplifies the complexity of the signature. By simultaneously utilizing the secondary distribution and rearrangement of non-entangled quantum states, a non-entangled quantum state representation of three bits of classical information is achieved, reducing the use of a large amount of quantum resources and lowering implementation costs. This improves both signature verification efficiency and communication efficiency while, at the same time, this scheme meets the requirements of unforgeability, non-repudiation, and prevention of information leakage.

关键词： quantum blind signature dense coding non-entanglement Hadamard gate

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Three Types of Isocoumarins with Unusual Carbon Skeletons from Artemisia dubia var. subdigitata and Their Antihepatoma Activity

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Chinese Journal of Chemistry 2024年第16期42卷 1901-1912页

作者： ke-Xin Yang Tian-Ze Li Yun-Bao Ma yong-Cui Wang Feng-Jiao Li Ji-Jun Chen State key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China

Ten novel isocoumarins,including four pairs of enantiomers,were isolated from Artemisia dubia ***(Asteraceae).Compounds 1,2 and 3a/3b possessed a unique 6/6/6-tricyclic system comprising an unusual 1-(2-methylcyclohexyl)propan-1-one moiety fused with isocoumarin core *** 4a/4b were characterized as an unexpected 2,5-dimethylcyclohexan-1-one scaffold,and compounds 5a/5b and 6a/6b were rare 1,*** structures and absolute configurations were elucidated through spectroscopic data,X-ray crystallography,ECD and NMR calculations with DP4+*** biosynthetic pathways were proposed from the naturally occurring *** pharmacological analysis suggested that the targets of compound 1 were significantly enriched in the cell cycle and Pl3K-Akt signaling *** molecular docking revealed that compound 1 had high binding affinity with CDK2(total score:6.8717).Furthermore,compounds 1 and 2 exhibited inhibitory activity on three human hepatoma cell lines,with inhibitory ratios of 85.1% and 84.5%(HepG2),88.2% and 87.3%(Huh7),and 69.2% and 69.1%(SK-Hep-1)at 200μmol·L^(-1),respectively.

关键词： Artemisia dubia var.subdigitata Isocoumarins Antihepatoma activity Cancer Natural products X-ray diffraction

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基模磁激元诱导的多带完美吸收

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工程热物理学报 2021年第1期42卷 196-202页

作者：蔡月培黄勇朱克勇北京航空航天大学航空科学与工程学院北京100191

本文提出一种方向不敏感多带吸收的新结构,即结合光学声子色散材料及无色散介电材料,将其作为单一尺寸金属/介质/金属微光栅的介质分离层。在红外大气窗口波段激发了基模磁激元谐振因此导致多频带吸收。基于有限元方法求解了混合结构的... 详细信息

本文提出一种方向不敏感多带吸收的新结构,即结合光学声子色散材料及无色散介电材料,将其作为单一尺寸金属/介质/金属微光栅的介质分离层。在红外大气窗口波段激发了基模磁激元谐振因此导致多频带吸收。基于有限元方法求解了混合结构的吸收率及电磁场分布,并研究了入射角及结构参数的变化对多峰值吸收的影响。考虑到磁激元的本质是由金属光栅下表面与金属基底上表面诱导出反向电流震荡引起,多层介质膜起到介电隔离层的作用。对多层介质膜进行等效介质理论近似,并通过等效LC电路预测和分析了基模磁激元谐振频点。本文所提出的多带吸收机理在红外探测、辐射制冷领等域具有应用前景。

关键词：光学声子等效介质磁激元多带完美吸收

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