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Contrasting Response Patterns of Rice Phyllosphere Bacterial Taxa to Elevated CO_2

Pedosphere 2014年第4期24卷 544-552页

作者： REN Gai-Di ZHU jian-Guo jia zhong-jun Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China University of Chinese Academy of Sciences Beijing 100049 China

A vast number of microorganisms colonize the leaf surface of terrestrial plants, known as the phyllosphere, and these microorganisms are thought to be of critical importance in plant growth and health. However, the taxonomic identities and ecological functions of the microorganisms inhabiting the rice phyllosphere remain poorly understood. Using a massive, parallel pyrosequencing technique, we identified the phyllosphere bacterial taxa of four different rice varieties and investigated the microbial response to elevated CO2 （eCO2） in a rice field of a free-air CO2 enrichment （FACE） facility located in jiangsu Province, China. The results showed that the dominant phylotype, the Enterobacteriaceae family of Gammaproteobacteria~ accounted for 70.6%-93.8% of the total bacterial communities in the rice phyllosphere. The dominant phylotype was stimulated by eCO2, with its relative abundance increasing from 70.6%-75.2% at ambient CO2 （aCO2） to 86.5%-93.8% at eCO2 in the phyllosphere of rice varieties IIYou084 （TY-084）, YangLiangYou6 （YLY-6）, and ZhenXian96 （ZX-96）. The rare phylotypes, including the bacterial taxa of Sphingobacteriaceae, Xanthomonadaceae, Oxalobacteraceae, Clostridiaceae, and Pseudomonadaceae, were suppressed and their relative abundance decreased from 13.4%-23.0% at aCO2 to 1.47% 6.11% at eGO2. Furthermore, the bacterial diversity indices decreased at eCO2 in the phyllosphere of the rice varieties TY-084, YLY-6, and ZX-96. In contrast, an opposite response pattern was observed for the rice variety of YangDao8 （YD-8）. In the phyllosphere of this variety, the relative abundance of the dominant phylotype, Enterobacteriaceae, decreased from 94.1% at aCO2 to 81.4% at eCO2, while that of the rare phylotypes increased from 3.37% to 6.59%. In addition, eCO2 appeared to stimulate bacterial diversity in the rice variety YD-8. Our results suggest that the phyllosphere microbial response to eCO2 might be relative abundance-dependent in paddy fields.

关键词： bacterial diversity free-air CO2 enrichment microbial response paddy field pyrosequencing rice variety

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Correction of distorted X-ray absorption spectra collected with capillary sample cell

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Nuclear Science and Techniques 2023年第7期34卷 179-188页

作者： Hao Wang Yue-Cheng Lai jia-jun zhong Yun-Peng Liu Lei Yao Li-Xiong Qian Xue-Qing Xing zhong-jun Chen Guang Mo zhong-Hua Wu Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

In certain exceptional cases,capillary samples must be used to measure X-ray absorption spectra(XAS).However,the inho-mogeneous thickness of capillary samples causes XAS *** study discusses the distortion and correction of the XAS curve caused by the inhomogeneous thickness of capillary *** relationship between the distorted XAS curveμ′d_(eq)(measured values)and the real absorption coefficientμ_(s)d_(eq)(true values)of the sample was *** distortion was slight and negligible when the vertical size(2h)of the X-ray beam spot was smaller than 60%of the capillary tube’s inner diameter(2R_(in)).When h/R_(in)>1,X-ray leakage is inevitable and should be avoided during *** X-ray leakage caused by an X-ray beam spot size larger than the inner diameter of the capillary tube leads to serious compressed distortion of the XAS *** h/R_(in)<1,the distorted XAS data were well *** errors and their influence on the corrected XAS are also *** and corrections for distortions verify the feasibility and effectiveness of the corrected method.

关键词： XAS Capillary Compression distortion Correction Python

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Silicon PIN photodiode applied to acquire high-frequency sampling XAFS spectra

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Nuclear Science and Techniques 2022年第7期33卷 15-24页

作者： Yun-Peng Liu Lei Yao Bing-Jie Wang jia-jun zhong Hao Wang Li-Xiong Qian zhong-jun Chen Guang Mo Xue-Qing Xing Wei-Fan Sheng zhong-Hua Wu Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing100049China

Experimental techniques based on SR facilities have emerged with the development of synchrotron radiation(SR)***,detector miniaturization has become significant for the development of SR experimental *** this study,the miniaturization of a detector was achieved by coupling a commercial silicon PIN photodiode(SPPD)into a beamstop,aiming for it not only to acquire X-ray absorption fine structure(XAFS)spectra,but also to protect the subsequent two-dimensional detector from high-brilliance X-ray radiation damage in certain combination *** mini SPPD detector coupled to a beamstop was used as the rear detector in both the conventional sampling scheme and novel high-frequency(HF)sampling scheme to collect the transmission XAFS *** ion chambers were also used to collect the transmission XAFS spectra,which were used as the *** XAFS spectra were quantitatively analyzed and compared;the results demonstrated that the XAFS spectra collected by this SPPD in both the conventional sampling scheme and HF sampling scheme are *** study provides a new detector-selection scheme for the acquisition of the quick-scanning XAFS(QXAFS)and HF sampling XAFS *** SPPD detector presented in this study can partially meet the requirements of detector miniaturization.

关键词： Silicon PIN photodiodes Beamstop XAFS High frequency sampling

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Multi-scale persistent spatiotemporal transformer for long-term urban traffic flow prediction

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Journal of Electronic Science and Technology 2024年第1期22卷 53-69页

作者： jia-jun zhong Yong Ma Xin-Zheng Niu Philippe Fournier-Viger Bing Wang Zu-kuan Wei School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China College of Computer Science&Software Engineering Shenzhen UniversityShenzhen518060China School of Computer Science Southwest Petroleum UniversityChengdu610500China

Long-term urban traffic flow prediction is an important task in the field of intelligent transportation,as it can help optimize traffic management and improve travel *** improve prediction accuracy,a crucial issue is how to model spatiotemporal dependency in urban traffic *** recent years,many studies have adopted spatiotemporal neural networks to extract key information from traffic ***,most models ignore the semantic spatial similarity between long-distance areas when mining spatial *** also ignore the impact of predicted time steps on the next unpredicted time step for making long-term ***,these models lack a comprehensive data embedding process to represent complex spatiotemporal *** paper proposes a multi-scale persistent spatiotemporal transformer(MSPSTT)model to perform accurate long-term traffic flow prediction in *** adopts an encoder-decoder structure and incorporates temporal,periodic,and spatial features to fully embed urban traffic data to address these *** model consists of a spatiotemporal encoder and a spatiotemporal decoder,which rely on temporal,geospatial,and semantic space multi-head attention modules to dynamically extract temporal,geospatial,and semantic *** spatiotemporal decoder combines the context information provided by the encoder,integrates the predicted time step information,and is iteratively updated to learn the correlation between different time steps in the broader time range to improve the model’s accuracy for long-term *** on four public transportation datasets demonstrate that MSPSTT outperforms the existing models by up to 9.5%on three common metrics.

关键词： Graph neural network Multi-head attention mechanism Spatio-temporal dependency Traffic flow prediction

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Microbial Community Changes Along a Land-Use Gradient of Desert Soil Origin

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Pedosphere 2012年第5期22卷 593-603页

作者： WANG Bao-Zhan ZHANG Cai-Xia LIU Ji-Liang ZENG Xiao-Wei LI Feng-Rui WU Yu-Cheng LIN Xian-Gui XIONG Zheng-Qin XU jian jia zhong-jun Institute of Soil Science Chinese Academy of SciencesNanjing 210008(China) Nanjing Agricultural University Nanjing 210095(China) Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of SciencesLanzhou 730000(China) Qingdao Institute of BioEnergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101(China)

Soil harbors remarkably stabilize bacterial communities at the phylum level. However, no two soils have exactly the same structure of bacterial phyla. The structure of microbial community is strongly influenced by the type of land-use through changes in soil attributes. Using high-throughput pyrosequencing and quantitative polymerase chain reaction techniques, soil microbial community structures were investigated along a land-use gradient of 100- and 27-year farmlands, a 33-year Pinus forest, a 28-year poplar forest, and a 21-year shrubland, as well as a native desert from which all cultivated systems were converted. The results revealed that the dominant phylotypes in the native soil comprised primarily of Alphaproteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes, accounting for 〉 71.4% of the total bacterial 16S rRNA sequence reads. Changes in land-use led to a significant decrease in these dominant phylotypes down to 33.4%. In contrast, the phylotypes with low abundance, such as Acidobaeteria, Chloroflexi, Nitrospira, and Gammaproteobaeteria, increased sharply from 4.5%-5.9% in the native soil to 20.9% 30.2% of the total 16S rRNA gene sequences in the cultivated soils except for the soil from the shrubland. These contrasting changes in the major taxa appear to be correlated with the changes in soil attributes. For instance, bacterial and archaeal amoA genes were found to be 960- and 3 800-fold more abundant in the soil from the 100-year farmland than the native soil. The changes in numerically less dominant nitrifying phylotypes are consistent with soil inorganic nitrogen dynamics. Quantification of the 16S rRNA genes demonstrated that bacteria and archaea were about two to three orders of magnitude more abundant in the cultivated soil than in the native soil. Hence, land-use type affects the soil bacterial community structure, which has profound consequences on ecosystem function.

关键词： amoA ecosystem functions land-use type polymerase chain reaction pyrosequencing

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基于SEER数据库转移性胰腺腺癌患者早期死亡预测列线图模型构建和验证

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世界华人消化杂志 2023年第14期31卷 577-588页

作者：钟佳俊叶艳清赣南医学院第一附属医院消化内科江西省赣州市341000

背景胰腺腺癌(pancreatic adenocarcinoma,PCa)是一种高度侵袭性的恶性肿瘤,具有早期死亡的高风险(生存时间≤3 mo).因此,建立有效的列线图来预测转移性胰腺腺癌(metastatic pancreatic adenocarcinoma,mPCa)患者早期死亡的概率具有相... 详细信息

背景胰腺腺癌(pancreatic adenocarcinoma,PCa)是一种高度侵袭性的恶性肿瘤,具有早期死亡的高风险(生存时间≤3 mo).因此,建立有效的列线图来预测转移性胰腺腺癌(metastatic pancreatic adenocarcinoma,mPCa)患者早期死亡的概率具有相当重要的意义.目的构建并验证mPCa患者早期死亡的预测列线图模型.方法提取SEER数据库中2010-2015年符合条件的18603例mPCa患者,按7:3比例随机分为训练集和验证集,对训练集进行单因素及多因素Logistics回归分析确定早期死亡危险因素,从而进一步构建列线图,在训练集和验证集中通过受试者工作特征曲线(receiver operating characteristic curve,ROC)、校准曲线对列线图效能进行验证,使用决策曲线分析(decision curve analysis,DCA)评估列线图临床实用性.结果年龄、性别、肿瘤原发部位、肿瘤分化程度、T分期、N分期、脑转移、骨转移、肝转移、肺转移、手术、放疗、化疗是mPCa患者早期死亡的独立危险因素,基于这些变量构建了列线图.训练集和验证集ROC曲线下面积分别是0.810(95%CI:0.802-0.811)、0.802(95%CI:0.790-0.813),提示列线图有良好的区分度,校准曲线在训练集和验证集中均有较好的校准度,DCA结果表明,与TNM分期相比,列线图在预测早期死亡方面有更好的临床净效益.结论所构建的列线图对于mPCa患者的早期死亡具有良好的预测能力,有助于临床医生对mPCa患者实施个体化治疗方案.

关键词：胰腺腺癌 SEER 列线图早期死亡

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长期不同施肥模式对农田黑土微生物群落构建的影响

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生态与农村环境学报 2021年第11期37卷 1437-1448页

作者：高威王连峰贾仲君中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室江苏南京210008 中国科学院亚热带农业生态研究所亚热带农业生态重点实验室湖南长沙410125 中国科学院大学北京100049 大连交通大学环境与化学工程学院辽宁大连116028

高强度集约化农业管理模式影响土壤微生物区系及其功能。围绕我国典型黑土生态环境重点野外科学观测试验站36年的长期不同施肥管理土壤:不施肥(CK)、单施化肥(NPK)、单施有机肥(OM)和有机-无机肥配施(MNPK),研究了土壤肥力和微生物呼吸... 详细信息

高强度集约化农业管理模式影响土壤微生物区系及其功能。围绕我国典型黑土生态环境重点野外科学观测试验站36年的长期不同施肥管理土壤:不施肥(CK)、单施化肥(NPK)、单施有机肥(OM)和有机-无机肥配施(MNPK),研究了土壤肥力和微生物呼吸,并通过高通量测序技术和微生物群落构建模型探讨了长期不同施肥模式对土壤功能微生物演替的环境驱动机制。结果表明:长期施肥提升了土壤肥力,如土壤有机碳、全氮、有效磷含量以及微生物活性。不同施肥管理模式土壤微生物呼吸活性存在显著差异,由大到小依次为MNPK、OM、NPK和CK。与CK(以C计,186.9μg·g^(-1))相比,MNPK处理土壤微生物呼吸(以C计,228.7μg·g^(-1))增幅高达22.4%。差异物种分析(LEfSe)表明,NPK和MNPK处理具有相似的指示物种,主要为Dyella marensis、Bacillus megaterium和Herbaspirillum sp.,OM处理则主要包括Bacillus acidiceler和Bacillus megaterium。长期施肥刺激了氨氧化细菌(Nitrosospira)生长,NPK处理氨氧化细菌丰度增加3.61倍,而黑土中氨氧化古菌和亚硝酸盐氧化细菌的优势类群分别为Nitrososphaera和Nitrospira。微生物共存网络分析表明,MNPK处理土壤微生物的关联度最为紧密,其正向网络关联度占比高达99.6%,显著高于NPK处理的78.4%和OM处理的97.4%。βNTI分析表明,长期施肥导致微生物类群定向富集而强化了群落组装的确定性过程,且MNPK处理确定性过程占比最高。结构方程模型(SEMs)进一步分析表明,长期施肥模式土壤肥力提升与微生物区系活性呈显著正相关,其解释度>90%。上述结果表明,长期施肥显著刺激功能菌生长,改变土壤微生物区系,提升土壤肥力,且MNPK处理对土壤肥力及其功能稳定性的提升,明显优于NPK和OM处理。研究结果可为确立更为完善的农田黑土施肥管理制度提供科学依据。

关键词：黑土长期施肥高通量测序微生物群落构建关键微生物功能群

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番茄可溶性固形物的动态QTL及相关性状

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遗传 2010年第10期32卷 1077-1083页

作者：贾俊忠田丽萍薛琳魏亦农石河子大学生命科学学院新疆石河子832003 石河子大学药学院新疆石河子832003 石河子蔬菜研究所新疆石河子832003 新疆生产建设兵团绿洲生态重点实验室新疆石河子832003

利用TD22×HT-1-1-1-1组合产生的206个F2:3家系进行番茄可溶性固形物及相关性状的动态QTL定位,并对3个时期的可溶性固形物与果重、果型指数、可溶性糖、VC及有机酸进行相关性分析。结果表明在番茄果实发育的3个时期可溶性固形物的QTL位... 详细信息

利用TD22×HT-1-1-1-1组合产生的206个F2:3家系进行番茄可溶性固形物及相关性状的动态QTL定位,并对3个时期的可溶性固形物与果重、果型指数、可溶性糖、VC及有机酸进行相关性分析。结果表明在番茄果实发育的3个时期可溶性固形物的QTL位点存在差异,绿熟期和红熟期分别检测到4个、8个QTL位点,呈现动态变化,两个时期同时检测到LEaat006和Tomato|TC162363两个标记,对辅助选择育种有重要意义。研究发现3个时期可溶性固形物存在极显著差异,不同时期可溶性固形物的主要相关性状不同。绿熟期与可溶性糖呈显著正相关,与果重呈显著负相关;黄熟期与可溶性糖和有机酸呈显著正相关;红熟期与可溶性糖和有机酸呈显著正相关,与果重呈显著负相关。在各性状相关性分析的基础上建立线性回归模型,利用非参品种进行检验,拟合度达到95%以上。

关键词：番茄数量性状基因座(QTL) 可溶性固形物相关性状线性回归模型

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稳定性同位素DNA-SIP示踪中性紫色土的氨氧化过程

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环境科学 2019年第6期40卷 2930-2938页

作者：刘天琳王智慧闫小娟赵永鹏贾仲君蒋先军西南大学资源环境学院重庆400715 中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室南京210008

研究表明酸性土壤中氨氧化作用主要是由氨氧化古菌(ammonia-oxidizing archaea,AOA)催化进行;而在中性和碱性土壤中则主要是由氨氧化细菌(ammonia-oxidizing bacteria,AOB)主导.虽然AOA在中性土壤中具有很高的丰度,但其对硝化过程的贡... 详细信息

研究表明酸性土壤中氨氧化作用主要是由氨氧化古菌(ammonia-oxidizing archaea,AOA)催化进行;而在中性和碱性土壤中则主要是由氨氧化细菌(ammonia-oxidizing bacteria,AOB)主导.虽然AOA在中性土壤中具有很高的丰度,但其对硝化过程的贡献仍不清楚.因此本文选取p H为7. 2的中性紫色土为研究对象,通过稳定性同位素核酸探针技术结合克隆测序探究中性紫色土中活性氨氧化微生物群落组成.结果表明中性紫色土的净硝化速率为9. 68 mg·(kg·d)^(-1),AOA和AOB在中性紫色土中均有较高的丰度且共同推动硝化作用的进行.系统发育分析结果表明培养初期(0d)在数量上占优势的AOB为Nitrosospira Cluster 3a. 1,而Nitrosospira Cluster 3a. 2只占较小的一部分,经过56d的培养后Nitrosospira Cluster 3a. 2替代了Nitrosospira Cluster 3a. 1成为主导氨氧化的活性AOB.培养初期(0d)在数量上占优势的AOA是Nitrososphaera Subcluster 9,但经过培养后变为Nitrososphaera Subcluster 3. 2/3. 3.在培养期间AOA和AOB的群落结构均发生了改变.对^(13)C标记DNA的测序分析证明AOA和AOB在硝化过程中都起着重要作用,主导氨氧化的活性AOA和AOB主要分别隶属于Nitrososphaera Subcluster 3. 2/3. 3和Nitrosospira Cluster 3a. 2.本研究明确了AOA及AOB对中性紫色土氨氧化过程的推动作用并从微生物层面探究硝化作用的发生机制,为进一步研究紫色土中硝化作用提供理论基础.

关键词：硝化作用氨氧化微生物多样性休眠群落结构

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码分复用数字音频水印嵌入方案

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上海交通大学学报 2004年第12期38卷 2073-2077,2081页

作者：贾骏王朔中张新鹏上海大学通信与信息工程学院上海200072

结合人耳听觉特性,用扩频方法在音频信号中的听觉不敏感区域嵌入多路数字水印,从而实现码分复用.在对嵌入信息的检测中,除了少量系统参数外,数字水印的提取不需要原始信号,并且毋需精确同步.实验表明,该水印具有很好的隐蔽性;尤其是对... 详细信息

结合人耳听觉特性,用扩频方法在音频信号中的听觉不敏感区域嵌入多路数字水印,从而实现码分复用.在对嵌入信息的检测中,除了少量系统参数外,数字水印的提取不需要原始信号,并且毋需精确同步.实验表明,该水印具有很好的隐蔽性;尤其是对常见攻击,MP3编码具有良好的稳健性.

关键词：码分复用音频水印扩频心理听觉模型

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建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

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