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The ALMA-QUARKS Survey.Ⅰ.Survey Description and Data Reduction
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作者 刘训川 Tie Liu +31 位作者 lei zhu Guido Garay Hong-Li Liu Paul Goldsmith Neal Evans Kee-Tae Kim Sheng-Yuan Liu Fengwei Xu Xing Lu Anandmayee Tej Xiaofeng Mai Leonardo Bronfman Shanghuo Li Diego Mardones Amelia Stutz Ken'ichi Tatematsu Ke Wang Qizhou Zhang Sheng-Li Qin Jianwen Zhou Qiuyi Luo Siju Zhang Yu Cheng Jinhua He Qilao Gu Ziyang Li Zhenying Zhang Suinan Zhang Anindya Saha Lokesh Dewangan Patricio Sanhueza Zhiqiang Shen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期104-124,共21页
This paper presents an overview of the QUARKS survey,which stands for Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures."The QUARKS survey is observing139 m... This paper presents an overview of the QUARKS survey,which stands for Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures."The QUARKS survey is observing139 massive clumps covered by 156 pointings at Atacama Large Millimeter/submillimeter Array(ALMA)Band 6(λ~1.3 mm).In conjunction with data obtained from the ALMA-ATOMS survey at Band 3(λ~3 mm),QUARKS aims to carry out an unbiased statistical investigation of massive star formation process within protoclusters down to a scale of 1000 au.This overview paper describes the observations and data reduction of the QUARKS survey,and gives a first look at an exemplar source,the mini-starburst Sgr B2(M).The wide-b and width(7.5 GHz)and high-angular-resolution(~0."3)observations of the QUARKS survey allow for the resolution of much more compact cores than those could be done by the ATOMS survey,and to detect previously unrevealed fainter filamentary structures.The spectral windows cover transitions of species including CO,SO,N_(2)D^(+),SiO,H_(30)α,H_(2)CO,CH_(3)CN,and many other complex organic molecules,tracing gas components with different temperatures and spatial extents.QUARKS aims to deepen our understanding of several scientific topics of massive star formation,such as the mass transport within protoclusters by(hub-)filamentary structures,the existence of massive starless cores,the physical and chemical properties of dense cores within protoclusters,and the feedback from already formed high-mass young protostars. 展开更多
关键词 STARS formation-stars kinematics and dynamics-ISM clouds-ISM MOLECULES
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The Probability Density Function Related to Shallow Cumulus Entrainment Rate and Its Influencing Factors in a Large-Eddy Simulation
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作者 lei zhu Chunsong LU +5 位作者 Xiaoqi XU Xin HE Junjun LI Shi LUO Yuan WANG Fan WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期173-187,共15页
The process of entrainment-mixing between cumulus clouds and the ambient air is important for the development of cumulus clouds.Accurately obtaining the entrainment rate(λ)is particularly important for its parameteri... The process of entrainment-mixing between cumulus clouds and the ambient air is important for the development of cumulus clouds.Accurately obtaining the entrainment rate(λ)is particularly important for its parameterization within the overall cumulus parameterization scheme.In this study,an improved bulk-plume method is proposed by solving the equations of two conserved variables simultaneously to calculateλof cumulus clouds in a large-eddy simulation.The results demonstrate that the improved bulk-plume method is more reliable than the traditional bulk-plume method,becauseλ,as calculated from the improved method,falls within the range ofλvalues obtained from the traditional method using different conserved variables.The probability density functions ofλfor all data,different times,and different heights can be well-fitted by a log-normal distribution,which supports the assumed stochastic entrainment process in previous studies.Further analysis demonstrate that the relationship betweenλand the vertical velocity is better than other thermodynamic/dynamical properties;thus,the vertical velocity is recommended as the primary influencing factor for the parameterization ofλin the future.The results of this study enhance the theoretical understanding ofλand its influencing factors and shed new light on the development ofλparameterization. 展开更多
关键词 large-eddy simulation cumulus clouds entrainment rate probability density functions spatial and temporal distribution
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Diverse foraging strategies of breeding Swinhoe's Storm-petrel in the productive marginal sea of the Northwest Pacific
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作者 Yachang Cheng lei zhu +6 位作者 Lin Xue Shisheng Ma Nan Jia Shaoping Zang Zhihai Cao Jing Yuan Yang Liu 《Avian Research》 SCIE CSCD 2024年第1期27-34,共8页
Understanding the foraging behavior is essential for investigating seabird ecology and conservation,as well as monitoring the well-being of the marine environment.Breeding seabirds adopt diverse foraging strategies to... Understanding the foraging behavior is essential for investigating seabird ecology and conservation,as well as monitoring the well-being of the marine environment.Breeding seabirds adopt diverse foraging strategies to maximize energy gains and cope with the intensified challenges of parenting and self-maintenance.Such tradeoff may stem from the heterogeneity of food resources and the constraints of central place foraging.Nevertheless,abundant marine productivity could alleviate the energy limitation for seabirds,resulting in a consistent foraging approach.Here,we investigated the foraging strategy during the breeding season of a cryptic small-sized seabird,Swinhoe’s Storm-petrel(Hydrobates monorhis),in the Yellow Sea,a productive marginal sea of the Northwest Pacific.Using GPS tracking,we evaluated habitat preference,quantified the foraging strategy,and tested if environmental conditions and individual traits influence foraging trips.We found that Swinhoe’s Storm-petrels preferred nearshore areas with shallow water and engaged in primarily short foraging trips.Distinctive southeastward and southwestward strategies emerged when combining trip metrics,including foraging direction,duration,and maximum distance.The bathymetry,proximity to the coastline,and sea surface temperature differed in two foraging strategies.Foraging strategies exhibited flexibility between individuals,potentially explained by wing morphology,in which longer-winged birds are more likely to embark on longer-distance foraging trips.These findings highlight the impact of environmental factors and individual traits on seabirds’foraging decisions in productive marginal sea ecosystems.Our study also provides valuable insights into the foraging ecology of this Asian endemic storm-petrel. 展开更多
关键词 Behavioral strategy BIOLOGGING Central place foraging Marine primary productivity Seabird Sea surface temperature
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Numerical Simulation of Slurry Diffusion in Fractured Rocks Considering a Time-Varying Viscosity
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作者 lei zhu Bin Liu +3 位作者 Xuewei Liu Wei Deng Wenjie Yao Ying Fan 《Fluid Dynamics & Materials Processing》 EI 2024年第2期401-427,共27页
To analyze the effects of a time-varying viscosity on the penetration length of grouting,in this study cement slur-ries with varying water-cement ratios have been investigated using the Bingham’sfluidflow equation and ... To analyze the effects of a time-varying viscosity on the penetration length of grouting,in this study cement slur-ries with varying water-cement ratios have been investigated using the Bingham’sfluidflow equation and a dis-crete element method.Afluid-solid coupling numerical model has been introduced accordingly,and its accuracy has been validated through comparison of theoretical and numerical solutions.For different fracture forms(a single fracture,a branch fracture,and a fracture network),the influence of the time-varying viscosity on the slurry length range has been investigated,considering the change in the fracture aperture.The results show that under different fracture forms and the same grouting process conditions,the influence of the time-varying viscosity on the seepage length is 0.350 m. 展开更多
关键词 Time-varying viscosity binghamfluids UDEC numerical simulation grout penetration length aperture
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Transcriptome-Wide Identification and Functional Analysis of PgSQE08-01 Gene in Ginsenoside Biosynthesis in Panax ginseng C.A.Mey.
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作者 lei zhu Lihe Hou +5 位作者 Yu Zhang Yang Jiang Yi Wang Meiping Zhang Mingzhu Zhao Kangyu Wang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期313-327,共15页
Panax ginseng C.A.Mey.is an important plant species used in traditional Chinese medicine,whose primary active ingredient is a ginsenoside.Ginsenoside biosynthesis is not only regulated by transcription factors but als... Panax ginseng C.A.Mey.is an important plant species used in traditional Chinese medicine,whose primary active ingredient is a ginsenoside.Ginsenoside biosynthesis is not only regulated by transcription factors but also controlled by a variety of structural genes.Nonetheless,the molecular mechanism underlying ginsenoside biosynthesis has always been a topic in the discussion of ginseng secondary metabolites.Squalene epoxidase(SQE)is a key enzyme in the mevalonic acid pathway,which affects the biosynthesis of secondary metabolites such as terpenoid.Using ginseng transcriptome,expression,and ginsenoside content databases,this study employed bioinformatic methods to systematically analyze the genes encoding SQE in ginseng.We first selected six PgSQE candidates that were closely involved in ginsenoside biosynthesis and then identified PgSQE08-01 to be highly associated with ginsenoside biosynthesis.Next,we constructed the overexpression vector pCAMBIA3301-PgSQE08-01 and the RNAi vector pART27-PgSQE08-01 and transformed ginseng adventitious roots using Agrobacterium rhizogenes,to obtain positive hairy-root clones.Thereafter,quantitative reverse transcriptionpolymerase chain reaction and high-performance liquid chromatography were used to determine the expression of relevant genes and ginsenoside content,respectively.Then,we focused on the function of PgSQE08-01 gene,which was noted to be involved in ginsenoside biosynthesis.Thus,these findings not only provided a molecular basis for the identification of important functional genes in ginseng but also enriched genetic resources for the biosynthesis of ginsenosides using synthetic biology. 展开更多
关键词 Panax ginseng pgSQE08-01 gene squalene epoxidase GINSENOSIDE ginseng hairy roots
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MSC-exo一种新型细胞递送工具转运靶向基因调控胰腺癌增殖效应分析
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作者 朱磊 李瑞雪 +4 位作者 鲍长磊 黄晨宸 梁书鑫 赵振林 朱洪 《昆明医科大学学报》 CAS 2024年第2期39-48,共10页
目的 观察1种新型细胞递送工具(MSC-exo)转运靶向基因调控胰腺癌增殖效应。方法 透射电子显微镜(transmission electron microscope,TEM)和纳米颗粒跟踪分析技术(nanoparticle tracking analysis,NTA)鉴定人间充质干细胞外泌体(human me... 目的 观察1种新型细胞递送工具(MSC-exo)转运靶向基因调控胰腺癌增殖效应。方法 透射电子显微镜(transmission electron microscope,TEM)和纳米颗粒跟踪分析技术(nanoparticle tracking analysis,NTA)鉴定人间充质干细胞外泌体(human mesenchymal stem cell exosomes,MSC-exo)并转运miR-450a-5p进入CFPAC-1,探讨miR-450a-5p靶向BZW2抑制胰腺癌细胞增殖效应。基因技术处理Pc-BZW2,CCK-8、EdU、细胞划痕、Transwell验证MSC-exo与MSC-exo-miR-450a-5p对细胞的抑制作用。结果 与胰腺正常组织相比miR-450a-5p在胰腺癌组织中低表达(P<0.05),CFPAC-1细胞MSC-exo-miR-450a-5p外泌体标记蛋白CD63、TSG101表达高于MSC-exo(P<0.05)。CCK-8、EdU、细胞划痕、Transwell实验显示MSC-exo-miR-450a-5p较MSC-exo可显著抑制CFPAC-1细胞增殖、侵袭和迁移(P<0.05)。通过双荧光素酶实验证实,miR-450a-5p靶向BZW2,并且RT-qPCR和免疫印迹检测miR-450a-5p和BZW2表达成负性相关(P<0.05)。过表达BZW2,CCK-8、EdU、细胞划痕、Transwell实验均证实,pc-BZW2逆转MSC-exo-miR-450a-5p对CFPAC-1的抑癌功能,免疫印迹检测PCNA、Ki-67、MMP2、MMP9,结果与上述实验一致(P<0.05)。结论 hMSC-exo是1种新的递送系统,靶向BZW2转运miR-450a-5p抑制胰腺癌细胞的生物学恶性,为胰腺癌靶向治疗研究提供了重要线索。 展开更多
关键词 胰腺癌 间充质干细胞 外泌体 miR-450a-5p BZW2
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磁场对激光驱动Rayleigh-Taylor不稳定性影响的数值研究 被引量:1
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作者 孙伟 吕冲 +1 位作者 雷柱 仲佳勇 《物理学报》 SCIE EI CAS CSCD 北大核心 2022年第15期169-179,共11页
Rayleigh-Taylor不稳定性(RTI)作为流体和等离子体中基础的物理现象,在天体物理、空间物理以及工程领域扮演着重要角色.尤其在惯性约束核聚变(ICF)研究中,RTI等宏观流体不稳定性是不可回避的物理问题.本文利用开源的辐射磁流体模拟程序F... Rayleigh-Taylor不稳定性(RTI)作为流体和等离子体中基础的物理现象,在天体物理、空间物理以及工程领域扮演着重要角色.尤其在惯性约束核聚变(ICF)研究中,RTI等宏观流体不稳定性是不可回避的物理问题.本文利用开源的辐射磁流体模拟程序FLASH对激光驱动调制靶产生的RTI进行了二维的数值模拟,系统地考察和比较了RTI在无磁场、Biermann自生磁场、不同外加磁场情况下的演化.模拟结果表明,Biermann自生磁场和平行流向的外加磁场在RTI演化过程中基本不会改变RTI的界面动力学,而垂直流向的外加磁场对RTI以及RTI尖钉尾部的Kelvin-Helmholtz涡旋有致稳作用,其中磁压力起主导作用.研究结果为后续开展和ICF相关的靶物理研究提供借鉴,也有助于加深对流体混合过程的理解. 展开更多
关键词 磁场 RAYLEIGH-TAYLOR不稳定性 KELVIN-HELMHOLTZ不稳定性
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磁场对激光驱动的喷流演化影响的二维数值研究
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作者 孙伟 吕冲 +2 位作者 雷柱 王钊 仲佳勇 《物理学报》 SCIE EI CAS CSCD 北大核心 2023年第9期297-306,共10页
喷流的触发机制、准直传输和稳定性一直是天体物理学的研究热点.近年通过观测和实验室研究发现磁场在喷流准直传输和加速中起着关键作用.本文利用开源的辐射磁流体模拟程序FLASH对强激光驱动聚苯乙烯(CH)平面靶产生的靶前喷流进行了二... 喷流的触发机制、准直传输和稳定性一直是天体物理学的研究热点.近年通过观测和实验室研究发现磁场在喷流准直传输和加速中起着关键作用.本文利用开源的辐射磁流体模拟程序FLASH对强激光驱动聚苯乙烯(CH)平面靶产生的靶前喷流进行了二维的数值模拟,系统地考察和比较了Biermann自生磁场以及不同方向、不同初始强度的外加磁场对喷流演化的动力学.模拟结果表明Biermann自生磁场不会影响喷流的界面动力学,而外加磁场对等离子体出流具有重定向作用,平行于靶前等离子体出流中心流向的外加磁场有助于喷流的产生和准直传输.其形成和演化过程是等离子体热压、磁压以及冲压三者相互竞争的结果.在受力方面,在喷流演化过程中等离子体热压梯度力和磁压力起决定性作用.研究结果为后续开展和喷流相关的实验研究提供借鉴,也有助于加深对天体喷流演化的理解. 展开更多
关键词 强激光 磁场 喷流
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两种高能束焊TC4合金接头的低周疲劳性能比较
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作者 龙健 张林杰 +3 位作者 朱磊 张黎旭 吴军 庄明祥 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第11期3376-3386,共11页
比较30mm厚Ti6Al4V钛合金真空电子束焊接和激光摆动填丝焊接头的低周疲劳性能。测试结果表明,电子束焊接头的低周疲劳性能接近母材,而激光填丝焊接头的低周疲劳性能明显不如电子束焊接头和母材。通过研究两个接头的母材、热影响区和焊... 比较30mm厚Ti6Al4V钛合金真空电子束焊接和激光摆动填丝焊接头的低周疲劳性能。测试结果表明,电子束焊接头的低周疲劳性能接近母材,而激光填丝焊接头的低周疲劳性能明显不如电子束焊接头和母材。通过研究两个接头的母材、热影响区和焊缝区的显微硬度,发现电子束焊接头的焊缝区显微硬度与母材的接近,但均低于热影响区的显微硬度,而激光填丝焊接头的焊缝区明显弱化。 展开更多
关键词 TI6AL4V钛合金 显微组织 显微硬度 低周疲劳
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Graph CA: Learning From Graph Counterfactual Augmentation for Knowledge Tracing
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作者 Xinhua Wang Shasha Zhao +3 位作者 lei Guo lei zhu Chaoran Cui Liancheng Xu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第11期2108-2123,共16页
With the popularity of online learning in educational settings, knowledge tracing(KT) plays an increasingly significant role. The task of KT is to help students learn more effectively by predicting their next mastery ... With the popularity of online learning in educational settings, knowledge tracing(KT) plays an increasingly significant role. The task of KT is to help students learn more effectively by predicting their next mastery of knowledge based on their historical exercise sequences. Nowadays, many related works have emerged in this field, such as Bayesian knowledge tracing and deep knowledge tracing methods. Despite the progress that has been made in KT, existing techniques still have the following limitations: 1) Previous studies address KT by only exploring the observational sparsity data distribution, and the counterfactual data distribution has been largely ignored. 2) Current works designed for KT only consider either the entity relationships between questions and concepts, or the relations between two concepts, and none of them investigates the relations among students, questions, and concepts, simultaneously, leading to inaccurate student modeling. To address the above limitations,we propose a graph counterfactual augmentation method for knowledge tracing. Concretely, to consider the multiple relationships among different entities, we first uniform students, questions, and concepts in graphs, and then leverage a heterogeneous graph convolutional network to conduct representation learning.To model the counterfactual world, we conduct counterfactual transformations on students’ learning graphs by changing the corresponding treatments and then exploit the counterfactual outcomes in a contrastive learning framework. We conduct extensive experiments on three real-world datasets, and the experimental results demonstrate the superiority of our proposed Graph CA method compared with several state-of-the-art baselines. 展开更多
关键词 Contrastive learning counterfactual representation graph neural network knowledge tracing
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Temperature-Triggered Hardware Trojan Based Algebraic Fault Analysis of SKINNY-64-64 Lightweight Block Cipher
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作者 lei zhu Jinyue Gong +1 位作者 Liang Dong Cong Zhang 《Computers, Materials & Continua》 SCIE EI 2023年第6期5521-5537,共17页
SKINNY-64-64 is a lightweight block cipher with a 64-bit block length and key length,and it is mainly used on the Internet of Things(IoT).Currently,faults can be injected into cryptographic devices by attackers in a v... SKINNY-64-64 is a lightweight block cipher with a 64-bit block length and key length,and it is mainly used on the Internet of Things(IoT).Currently,faults can be injected into cryptographic devices by attackers in a variety of ways,but it is still difficult to achieve a precisely located fault attacks at a low cost,whereas a Hardware Trojan(HT)can realize this.Temperature,as a physical quantity incidental to the operation of a cryptographic device,is easily overlooked.In this paper,a temperature-triggered HT(THT)is designed,which,when activated,causes a specific bit of the intermediate state of the SKINNY-64-64 to be flipped.Further,in this paper,a THT-based algebraic fault analysis(THT-AFA)method is proposed.To demonstrate the effectiveness of the method,experiments on algebraic fault analysis(AFA)and THT-AFA have been carried out on SKINNY-64-64.In the THT-AFA for SKINNY-64-64,it is only required to activate the THT 3 times to obtain the master key with a 100%success rate,and the average time for the attack is 64.57 s.However,when performing AFA on this cipher,we provide a relation-ship between the number of different faults and the residual entropy of the key.In comparison,our proposed THT-AFA method has better performance in terms of attack efficiency.To the best of our knowledge,this is the first HT attack on SKINNY-64-64. 展开更多
关键词 SKINNY-64-64 lightweight block cipher algebraic fault analysis Hardware Trojan residual entropy
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MSCNN-LSTM Model for Predicting Return Loss of the UHF Antenna in HF-UHF RFID Tag Antenna
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作者 Zhao Yang Yuan Zhang +4 位作者 lei zhu lei Huang Fangyu Hu Yanping Du Xiaowei Li 《Computers, Materials & Continua》 SCIE EI 2023年第5期2889-2904,共16页
High-frequency(HF)and ultrahigh-frequency(UHF)dual-band radio frequency identification(RFID)tags with both near-field and farfield communication can meet different application scenarios.However,it is time-consuming to... High-frequency(HF)and ultrahigh-frequency(UHF)dual-band radio frequency identification(RFID)tags with both near-field and farfield communication can meet different application scenarios.However,it is time-consuming to calculate the return loss of a UHF antenna in a dualband tag antenna using electromagnetic(EM)simulators.To overcome this,the present work proposes a model of a multi-scale convolutional neural network stacked with long and short-term memory(MSCNN-LSTM)for predicting the return loss of UHF antennas instead of EM simulators.In the proposed MSCNN-LSTM,the MSCNN has three branches,which include three convolution layers with different kernel sizes and numbers.Therefore,MSCNN can extract fine-grain localized information of the antenna and overall features.The LSTM can effectively learn the EM characteristics of different structures of the antenna to improve the prediction accuracy of the model.Experimental results show that the mean absolute error(0.0073),mean square error(0.00032),and root mean square error(0.01814)of theMSCNNLSTM are better than those of other prediction methods.In predicting the return loss of 100UHFantennas,compared with the simulation time of 4800 s for High Frequency Structure Simulator(HFSS),MSCNN-LSTM takes only 0.927519 s under the premise of ensuring prediction accuracy,significantly reducing the calculation time,which provides a basis for the rapid design of HF-UHF RFID tag antenna.ThenMSCNN-LSTM is used to determine the dimensions of the UHF antenna quickly.The return loss of the designed dualband RFID tag antenna is−58.76 and−22.63 dB at 13.56 and 915 MHz,respectively,achieving the desired goal. 展开更多
关键词 HF-UHF RFID tag antenna multi-scale convolutional neural network long-short term memory return loss
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Identification of candidate genes that regulate the trade-off between seedling cold tolerance and fruit quality in melon (Cucumis melo L.)
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作者 Lili Li Qiong Li +16 位作者 Bin Chen Jiyu Wang Fei Ding Panqiao Wang Xiuyue Zhang Juan Hou Renren Luo Xiang Li Jingwen Zheng Sen Yang Luming Yang lei zhu Shouru Sun Changsheng Ma Qin Li Ying Li Jianbin Hu 《Horticulture Research》 SCIE CSCD 2023年第7期7-21,共15页
Trade-offs between survival and growth are widely observed in plants.Melon is an annual,trailing herb that produces economically valuable fruits that are traditionally cultivated in early spring in China.Melon seedlin... Trade-offs between survival and growth are widely observed in plants.Melon is an annual,trailing herb that produces economically valuable fruits that are traditionally cultivated in early spring in China.Melon seedlings are sensitive to low temperatures,and thus usually suffer from cold stress during the early growth period.However,little is known about the mechanism behind the trade-offs between seedling cold tolerance and fruit quality in melon.In this study,a total of 31 primary metabolites were detected from the mature fruits of eight melon lines that differ with respect to seedling cold tolerance;these included 12 amino acids,10 organic acids,and 9 soluble sugars.Our results showed that concentrations of most of the primary metabolites in the cold-resistant melons were generally lower than in the cold-sensitive melons;the greatest difference in metabolite levels was observed between the cold-resistant line H581 and the moderately cold-resistant line HH09.The metabolite and transcriptome data for these two lines were then subjected to weighted correlation network analysis,resulting in the identification of five key candidate genes underlying the balancing between seedling cold tolerance and fruit quality.Among these genes,CmEAF7 might play multiple roles in regulating chloroplast development,photosynthesis,and the ABA pathway.Furthermore,multi-method functional analysis showed that CmEAF7 can certainly improve both seedling cold tolerance and fruit quality in melon.Our study identified an agriculturally important gene,CmEAF7,and provides a new insight into breeding methods to develop melon cultivars with seedling cold tolerance and high fruit quality. 展开更多
关键词 SEEDLING BREEDING CULTIVAR
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MicroRNA-584-5p/RUNX family transcription factor 2 axis mediates hypoxia-induced osteogenic differentiation of periosteal stem cells
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作者 Jia-Jia Lu Xiao-Jian Shi +3 位作者 Qiang Fu Yong-Chuan Li lei zhu Nan Lu 《World Journal of Stem Cells》 SCIE 2023年第10期979-988,共10页
BACKGROUND The hypoxic environment during bone healing is important in regulating the differentiation of periosteal stem cells(PSCs)into osteoblasts or chondrocytes;however,the underlying mechanisms remain unclear.AIM... BACKGROUND The hypoxic environment during bone healing is important in regulating the differentiation of periosteal stem cells(PSCs)into osteoblasts or chondrocytes;however,the underlying mechanisms remain unclear.AIM To determine the effect of hypoxia on PSCs,and the expression of microRNA-584-5p(miR-584-5p)and RUNX family transcription factor 2(RUNX2)in PSCs was modulated to explore the impact of the miR-584-5p/RUNX2 axis on hypoxiainduced osteogenic differentiation of PSCs.METHODS In this study,we isolated primary mouse PSCs and stimulated them with hypoxia,and the characteristics and functional genes related to PSC osteogenic differentiation were assessed.Constructs expressing miR-584-5p and RUNX2 were established to determine PSC osteogenic differentiation.RESULTS Hypoxic stimulation induced PSC osteogenic differentiation and significantly increased calcified nodules,intracellular calcium ion levels,and alkaline phosphatase(ALP)activity in PSCs.Osteogenic differentiation-related factors such as RUNX2,bone morphogenetic protein 2,hypoxia-inducible factor 1-alpha,and ALP were upregulated;in contrast,miR-584-5p was downregulated in these cells.Furthermore,upregulation of miR-584-5p significantly inhibited RUNX2 expression and hypoxia-induced PSC osteogenic differentiation.RUNX2 was the target gene of miR-584-5p,antagonizing miR-584-5p inhibition in hypoxia-induced PSC osteogenic differentiation.CONCLUSION Our study showed that the interaction of miR-584-5p and RUNX2 could mediate PSC osteogenic differentiation induced by hypoxia. 展开更多
关键词 Periosteal stem cell Osteogenic differentiation RUNX family transcription factor 2 MiroRNA-584-5p
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替莫唑胺剂量密度方案联合顺铂治疗复发高级别胶质瘤效果观察 被引量:10
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作者 廖加群 黄立敏 +4 位作者 易敏 吴坤励 曹雪 雷竹 杨洁 《山东医药》 CAS 2018年第15期9-11,共3页
目的观察替莫唑胺(TMZ)剂量密度方案联合顺铂治疗复发的高级别胶质瘤的临床效果。方法 36例复发高级别胶质瘤(WHOⅢ、IV级)患者,分为A、B、C组各12例。A组采用TMZ剂量密度方案联合顺铂化疗:D1、D2TMZ 75 mg/(m2·d)口服+顺铂40 mg/(... 目的观察替莫唑胺(TMZ)剂量密度方案联合顺铂治疗复发的高级别胶质瘤的临床效果。方法 36例复发高级别胶质瘤(WHOⅢ、IV级)患者,分为A、B、C组各12例。A组采用TMZ剂量密度方案联合顺铂化疗:D1、D2TMZ 75 mg/(m2·d)口服+顺铂40 mg/(m2·d)静滴,D3~21TMZ 75 mg/(m2·d)口服;B组采用TMZ剂量密度方案化疗:D1~21TMZ 75 mg/(m2·d)口服;C组采用TMZ标准方案化疗:D1~5TMZ 150 mg/(m2·d)口服,如患者耐受良好,无明显不良反应,第2周期将TMZ调整为200 mg/(m2·d)。3组均治疗28天为1个治疗周期。采用神经肿瘤评价标准评价3组疗效,计算治疗总有效率(RR)、疾病控制率(DCR),观察治疗过程中不良反应(毒性反应、消化道反应、骨髓抑制、肝肾功能等)发生情况。结果 A、B、C组RR分别为50%、25%、25%,A组RR高于B、C组,P均<0.05;A、B、C组DCR分别为75%、50%、33.3%,A组DCR高于B、C组,P均<0.05。A、B、C组6个月无疾病进展生存(PFS)率分别为66.7%、33.3%、25.0%,A组6个月PFS率高于B、C组,P均<0.05,1年生存率分别为25.0%、16.7%、16.7%,P均>0.05。各组不良反应间差异无统计学意义。结论 TMZ剂量密度方案联合顺铂治疗复发高级别胶质瘤临床效果好,效果优于单独应用TMZ治疗者。 展开更多
关键词 替莫唑胺 顺铂 联合用药 胶质瘤 高级别胶质瘤 复发胶质瘤
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低剂量诊断性放疗联合化疗在诊治颅内生殖细胞肿瘤中的价值 被引量:11
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作者 黄立敏 雷竹 +5 位作者 曹雪 骆雯 廖加群 吴海霞 杨洁 邱晓光 《中国癌症杂志》 CAS CSCD 北大核心 2018年第4期270-275,共6页
背景与目的:颅内生殖细胞肿瘤(intracranial germ cell tumors)经积极放化疗常可获得令人满意的局部控制率和生存率,然而对部分无法取得病理诊断的颅内生殖细胞肿瘤的治疗,研究者们至今无法达成一致意见。该研究探讨低剂量诊断性放疗联... 背景与目的:颅内生殖细胞肿瘤(intracranial germ cell tumors)经积极放化疗常可获得令人满意的局部控制率和生存率,然而对部分无法取得病理诊断的颅内生殖细胞肿瘤的治疗,研究者们至今无法达成一致意见。该研究探讨低剂量诊断性放疗联合化疗在诊治颅内生殖细胞肿瘤的可行性及临床意义。方法:该研究分析了贵州省人民医院及北京天坛医院收治的28例(16例男性,12例女性,中位年龄14.5岁)高度怀疑为颅内生殖细胞肿瘤的患者。患者血浆和(或)脑脊液人绒毛膜促性腺激素(β-human chorionic gonadotropin,β-HCG)和甲胎蛋白(α-fetoprotein,AFP)均为阴性,头颅MRI诊断提示鞍区和(或)松果体区呈典型生殖细胞肿瘤影像特征,临床表现高度提示可能为生殖细胞瘤(germinoma)。这些患者因无法通过手术及立体定向活检明确病理诊断,或患者本身不同意手术或活检,因此我们建议实施诊断性低剂量放疗联合化疗方案,诊断性放疗剂量为3.4 Gy,1.7 Gy/2次。经低剂量诊断性放疗后行MRI复查。随后根据MRI复查结果采用以下治疗:⑴影像学为进展(progression disease,PD)或稳定(stable disease,SD),建议手术治疗。⑵影像学达完全缓解(complete response,CR)或部分缓解(partial release,PR),再予以2个周期化疗,顺铂+足叶乙甙(DDP+VP16)方案2个周期,化疗后再次行MRI复查,如果患者影像学检测结果显示达CR,随即按生殖细胞瘤进行调强放疗(intensity-modulated radiation therapy,IMRT)及三维适形放疗(three-dimensional conformal radiotherapy,3D-CRT)。放疗方案根据患者情况进行选择:(1)局部放疗;(2)全脑全脊髓+局部加量放疗;(3)全脑+局部加量放疗(松果体区病变总剂量小于等于50.4 Gy;鞍区病变总剂量小于等于41.0 Gy)。⑶经低剂量诊断性放疗联合化疗后行MRI复查,如果患者影像学仍未达CR,建议患者立即接受手术治疗。参考WHO实体瘤疗效评价标准判断放化疗效果。结果:经诊断性放疗后显示为SD的患者1例,被随后的手术证实为垂体瘤。经低剂量诊断性放化疗后,病灶影像学诊断结果显示26例达CR,考虑临床诊断为颅内生殖细胞肿瘤,随即予患者行IMRT及3D-CRT;治疗后影像学复查均为CR,以上患者随访时间1~8年,所有患者均无瘤生存,无复发,未见放射性坏死。经诊断性放疗及2个周期化疗后仍有1例患者影像学诊断结果显示未达到CR,后经手术证实为混合性生殖细胞肿瘤。结论:低剂量诊断性放疗联合化疗具备区分颅内生殖细胞瘤与非生殖细胞瘤的能力,对高度怀疑为颅内生殖细胞肿瘤的患者,在没有病理证实的情况下,可参考此方案进行诊断性治疗和临床处理。 展开更多
关键词 颅内生殖细胞肿瘤 生殖细胞瘤 诊断性放疗 化疗
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磁共振3D-ASL技术在高级别胶质瘤靶区勾画术后残留病灶识别中的应用 被引量:5
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作者 黄立敏 雷竹 +6 位作者 张瑜 李勇 侯净 许钟 曹辉 王涛 杨洁 《中国癌症杂志》 CAS CSCD 北大核心 2019年第11期875-879,共5页
背景与目的:高级别胶质瘤呈浸润性生长,手术通常难以完全切除,术后联合放化疗能改善患者的预后。探讨三维动脉自旋标记(three-dimensional arterial spin labeling,3D-ASL)技术联合对比增强扫描在诊断胶质瘤患者术后残留中的价值,为放... 背景与目的:高级别胶质瘤呈浸润性生长,手术通常难以完全切除,术后联合放化疗能改善患者的预后。探讨三维动脉自旋标记(three-dimensional arterial spin labeling,3D-ASL)技术联合对比增强扫描在诊断胶质瘤患者术后残留中的价值,为放疗靶区勾画提供准确定位。方法:对贵州省人民医院2015年3月-2017年5月经手术后病理学检查证实的30例术后高级别胶质瘤患者(其中Ⅲ级12例,Ⅳ级18例)行常规MRI、3D-ASL扫描。通过联合常规MRI及3D-ASL序列进行分析,计算感兴趣区肿瘤血流灌注值(tumor blood flow,TBF)、对侧正常白质的区域血流灌注值(contralateral white matter blood flow,CBFwm)及标准化肿瘤血流量(normalized tumor blood flow,nTBF),nTBF=TBF/CBFwm。进行t检验统计学处理。结果:GE 3D-ASL灌注图显示,胶质瘤术后残留组(20例)呈高血流灌注,术后残腔组(10例)呈低血流灌注。术后残留组TBF与nTBF均高于术后残腔组,术后残留组TBF:(85.97±17.54)mL/min,nTBF:4.19±1.58,术后残腔组TBF:(26.51±8.93)mL/min,nTBF:0.91±0.44,差异有统计学意义(P<0.01);但CBFwm差异无统计学意义(P>0.05)。结论:磁共振3D-ASL技术联合对比增强扫描可以半定量测定高级别胶质瘤灌注情况,对于高级别胶质瘤患者的术后残留病灶有定位及定性诊断的价值,对于精确勾画放疗靶区具有实用价值。 展开更多
关键词 高级别胶质瘤 三维动脉自旋标记 放疗 肿瘤血流灌注值
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阿托伐他汀对激素性股骨头坏死大鼠的作用及对Wnt/β-catenin信号通路的影响 被引量:2
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作者 朱磊 周正新 +8 位作者 顾一帆 李文华 李亮 刘涛 康金平 韩士鼎 徐寰 朱彩玉 王壮壮 《中国现代医学杂志》 CAS 北大核心 2022年第24期34-39,共6页
目的探究阿托伐他汀对激素性股骨头坏死大鼠的作用及对果蝇无翅基因/β-连环蛋白(Wnt/β-catenin)信号通路的影响。方法30只SD雄性大鼠随机分为对照组、模型组及阿托伐他汀组,每组10只。模型组和阿托伐他汀组复制激素性股骨头坏死模型... 目的探究阿托伐他汀对激素性股骨头坏死大鼠的作用及对果蝇无翅基因/β-连环蛋白(Wnt/β-catenin)信号通路的影响。方法30只SD雄性大鼠随机分为对照组、模型组及阿托伐他汀组,每组10只。模型组和阿托伐他汀组复制激素性股骨头坏死模型并对每只大鼠腹腔注射醋酸泼尼松龙(24.5 mg/kg)和青霉素钠(8万u),2次/周,连续给药6周,共18只大鼠模型复制成功。模型复制的同时,阿托伐他汀组腹腔注射阿托伐他汀1 mg/(kg·d),对照组与模型组给予等量的生理盐水,连续治疗6周后,检测各组大鼠血清钙(S-Ca)、血清磷(S-P)水平,以及血清碱性磷酸酶(ALP)、转化生长因子β_(1)(TGF-β_(1))水平;比较大鼠骨组织ALP、TGF-β_(1)mRNA相对表达量;比较大鼠骨组织Wnt1、β-catenin蛋白的表达。结果与对照组比较,模型组大鼠血清S-Ca、S-P及TGF⁃β_(1)水平降低(P<0.05),ALP水平升高(P<0.05),ALP mRNA相对表达量升高(P<0.05),TGF⁃β_(1)mRNA相对表达量降低(P<0.05),Wnt1水平和β-catenin蛋白相对表达量下降(P<0.05);与模型组比较,阿托伐他汀组大鼠血清S-Ca、S-P及TGF⁃β_(1)水平升高(P<0.05),ALP水平降低(P<0.05),ALP mRNA相对表达量下降(P<0.05),TGF-β_(1)mRNA相对表达量升高(P<0.05),Wnt1水平和β-catenin蛋白相对表达量升高(P<0.05)。结论阿托伐他汀能够改善激素性股骨头坏死大鼠骨代谢指标,其机制可能与Wnt/β-catenin信号通路有关。 展开更多
关键词 激素性股骨头坏死 阿托伐他汀 大鼠 果蝇无翅基因/β-连环蛋白信号通路
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胃上部癌患者的临床病理特点及预后分析 被引量:2
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作者 周潮平 马军 +2 位作者 蒋鹏 朱磊 张亚铭 《中国肿瘤临床》 CAS CSCD 北大核心 2022年第4期184-187,共4页
目的:研究胃上部癌患者N05.6组淋巴结转移情况,探讨患者的临床病理特点及预后,分析影响患者预后的相关因素,为胃上部癌患者的合理术式提供理论依据。方法::回顾性分析2010年9月至2015年6月安庆市立医院肿瘤收治的231例胃上部癌患者的临... 目的:研究胃上部癌患者N05.6组淋巴结转移情况,探讨患者的临床病理特点及预后,分析影响患者预后的相关因素,为胃上部癌患者的合理术式提供理论依据。方法::回顾性分析2010年9月至2015年6月安庆市立医院肿瘤收治的231例胃上部癌患者的临床病理资料,根据患者术后病理结果,计算出N05.6组淋巴结转移情况。采用门诊及电话方式进行随访,截止至2018年6月。计数资料间的比较采用χ^(2)检验。Kaplan-Meier法绘制生存曲线,Log-rank检验进行生存分析及单因素分析。Cox回归进行多因素分析。结果:231例胃上部癌患者中,平均淋巴结清扫数目为18.60(4297/231)枚,N05.6组淋巴结转移率为8.23%(19/231),患者的不同N分期、TNM分期的N05.6组淋巴结转移情况进行比较,差异具有统计学意义(χ^(2)=14.219,13.171;P<0.05)。2例患者失访,随访率为99.13%(229/231),随访时间4~94个月,中位随访时间49个月,总体5年累积生存率70.30%。N05.6组淋巴结阳性的患者,中位生存时间为42个月,5年累积生存率48.6%;阴性的患者,中位生存时间为50个月,5年累积生存率71.9%,两者的比较差异具有统计学意义(χ^(2)=6.175,P<0.05)。单因素分析结果显示,肿瘤分化程度、N分期、TNM分期、N05.6组淋巴结转移情况是影响患者预后的相关因素(χ^(2)=4.583,28.224,9.136,6.175;P<0.05)。多因素分析结果显示,N分期是胃上部癌患者预后的独立危险因素(HR=0.096,95%CI:0.027~0.341,P<0.05)。结论::胃上部癌患者的淋巴结转移数目为预后的独立危险因素,对于T1、T2期无远处转移的胃上部癌患者可考虑行近端胃切除术。 展开更多
关键词 胃癌 淋巴结转移 预后
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供体来源半成熟树突状细胞诱导大鼠肝移植术后免疫低反应的实验研究 被引量:1
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作者 李春满 王伟 +5 位作者 张捷 唐波 李刚 董丽英 朱磊 付必莽 《中国现代医学杂志》 CAS 北大核心 2017年第16期18-23,共6页
目的研究供体来源半成熟树突状细胞(smDC)诱导大鼠肝移植术后免疫低反应的效果,初步分析其作用机制。方法该实验在成功完成大鼠树突状细胞(DC)培养和鉴定的基础上,进行大鼠肝移植术前输注供体来源DC、术后使用雷帕霉素灌胃,观察大鼠术... 目的研究供体来源半成熟树突状细胞(smDC)诱导大鼠肝移植术后免疫低反应的效果,初步分析其作用机制。方法该实验在成功完成大鼠树突状细胞(DC)培养和鉴定的基础上,进行大鼠肝移植术前输注供体来源DC、术后使用雷帕霉素灌胃,观察大鼠术后血清白细胞介素10(IL-10)和γ干扰素(IFN-γ)、CD4^+CD25^+Treg的变化,并评估急性免疫排斥病理改变。结果使用雷帕霉素后,可以改变血清细胞因子的分泌水平、促进Lewis→BN大鼠肝移植术后CD4^+CD25^+Treg的增殖,减轻术后免疫排斥反应,从而延长Lewis→BN大鼠肝移植术后生存时间。结合术前输注未成熟树突状细胞(imDC)或smDC,可以增强雷帕霉素的相应作用,进一步诱导大鼠肝移植术后免疫低反应,且smDC的作用强于imDC。结论 smDC可以诱导Lewis→BN大鼠肝移植术后免疫低反应。 展开更多
关键词 肝移植 半成熟树突状细胞 免疫排斥 调节性T细胞
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