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Late sowing enhances lodging resistance of wheat plants by improving the biosynthesis and accumulation of lignin and cellulose

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Journal of Integrative Agriculture 2023年第5期22卷 1351-1365页

作者： dong Xiu-chun QIAN Tai-feng CHU Jin-peng zhang Xiu LIU Yun-jing DAI Xing-long HE Ming-rong State Key Laboratory of Crop Biology Ministry of Science and Technology/Key Laboratory of Crop Ecophysiology and Farming SystemMinistry of Agriculture and Rural Affairs/Agronomy CollegeShandong Agricultural UniversityTai’an 271018P.R.China Jining Agricultural Technology Extension Center Jining 272113P.R.China

Delayed sowing mitigates lodging in wheat. However, the mechanism underlying the enhanced lodging resistance in wheat has yet to be fully elucidated. Field experiments were conducted to investigate the effects of sowing date on lignin and cellulose metabolism, stem morphological characteristics, lodging resistance, and grain yield. Seeds of Tainong 18,a winter wheat variety, were sown on October 8(normal sowing) and October 22(late sowing) during both of the 2015–2016 and 2016–2017 growing seasons. The results showed that late sowing enhanced the lodging resistance of wheat by improving the biosynthesis and accumulation of lignin and cellulose. Under late sowing, the expression levels of key genes(Ta PAL, Ta CCR, Ta COMT, TaCAD, and TaCesA1, 3, 4, 7, and 8) and enzyme activities(TaPAL and TaCAD) related to lignin and cellulose biosynthesis peaked 4–12 days earlier, and except for the TaPAL, TaCCR, and TaCesA1 genes and TaPAL, in most cases they were significantly higher than under normal sowing. As a result, lignin and cellulose accumulated quickly during the stem elongation stage. The mean and maximum accumulation rates of lignin and cellulose increased, the maximum accumulation contents of lignin and cellulose were higher, and the cellulose accumulation duration was prolonged. Consequently, the lignin/cellulose ratio and lignin content were increased from 0 day and the cellulose content was increased from 11 days after jointing onward. Our main finding is that the improved biosynthesis and accumulation of lignin and cellulose were responsible for increasing the stem-filling degree, breaking strength, and lodging resistance. The major functional genes enhancing lodging resistance in wheat that are induced by delayed sowing need to be determined.

关键词： cellulose late sowing lignin lodging resistance wheat

PPARγ激活和抑制状态下调控IFNβ表达的互作蛋白鉴定与分析

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农业生物技术学报 2024年第5期32卷 1081-1092页

作者：马卓媛杨玢陈云龙樊港吴晓龙王希音华进联王妍张永强张仕强西北农林科技大学动物医学院/陕西省干细胞工程技术研究中心西北农林科技大学家畜生物学重点实验室中国动物卫生与流行病学中心

过氧化物酶体增殖物激活受体γ (peroxisome proliferator activated receptor γ, PPARγ)在肺泡巨噬细胞中特异性高表达，具有代谢和免疫调控作用。在先天免疫诱导产生Ⅰ型干扰素过程中，PPARγ究竟与哪些互作蛋白共同参与该过程的调... 详细信息

过氧化物酶体增殖物激活受体γ (peroxisome proliferator activated receptor γ, PPARγ)在肺泡巨噬细胞中特异性高表达，具有代谢和免疫调控作用。在先天免疫诱导产生Ⅰ型干扰素过程中，PPARγ究竟与哪些互作蛋白共同参与该过程的调控目前尚不清楚。本研究利用慢病毒载体系统构建了稳定过表达PPARγ-3×Flag的野猪(Sus scrofa)肺细胞系(wild boar lung cell line, WSL)。以该细胞为模型，通过荧光定量PCR检测发现，添加PPARγ激动剂罗格列酮能显著降低双链DNA模拟物Poly (dA:dT)刺激诱发的干扰素β (interferon β, IFNβ)表达水平；相反，添加PPARγ抑制剂T0070907能显著提高Poly (dA:dT)刺激引起的IFNβ表达水平。进一步利用抗Flag蛋白的免疫磁珠富集沉淀调控上述过程的PPARγ-3×Flag蛋白复合物，将细胞质蛋白和细胞核蛋白富集的PPARγ-3×Flag复合物分别消化成肽段，利用液相色谱-串联质谱联用(liquid chromatograph-tandem mass spectrometer, LC-MS/MS)进行检测分析。结果发现，在添加PPARγ激动剂的条件下，与PPARγ特异互作的胞质蛋白有101个，胞核蛋白有95个；在添加PPARγ抑制剂的条件下，与PPARγ特异互作的胞质蛋白有24个，胞核蛋白有14个。GO和KEGG分析表明，与PPARγ特异互作的胞质蛋白和核蛋白均与翻译调控相关。本研究为深入探究PPARγ调控IFNβ表达机制提供了新线索。

关键词：过氧化物酶体增殖物激活受体γ(PPARγ) 干扰素β (IFNβ) 免疫沉淀-质谱联用先天免疫翻译调控

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致密砾岩水力裂缝扩展大型矿场实验

深圳大学学报（理工版） 2024年第2期41卷 173-182页

作者：张景臣石善志郭晓东吕振虎张兆鹏董景锋中国石油大学(北京)非常规油气科学技术研究院北京102249 中国石油新疆油田分公司工程技术研究院新疆克拉玛依834000 中国石油大学(北京)石油工程学院北京102249 新疆泰齐石油科技有限公司新疆克拉玛依834000

砾岩储层由于砾石的存在而具有极强的非均质性,砾岩压裂成缝机理复杂.受限于岩样尺寸和实验条件,室内压裂物理模拟受砾石尺寸效应影响显著,裂缝扩展时间尺度小.为真实记录裂缝动态扩展过程,反映现场实际工况条件下的压后裂缝宏观整体形... 详细信息

砾岩储层由于砾石的存在而具有极强的非均质性,砾岩压裂成缝机理复杂.受限于岩样尺寸和实验条件,室内压裂物理模拟受砾石尺寸效应影响显著,裂缝扩展时间尺度小.为真实记录裂缝动态扩展过程,反映现场实际工况条件下的压后裂缝宏观整体形态,搭建一套超大尺寸(2.0 m×2.0 m×1.0 m)真三轴水力压裂矿场实验平台,通过万吨级应力加载装置、真实管汇和压裂泵车,实现现场真实工况条件下的砾岩水力压裂模拟.基于该平台,分析了水平应力差、压裂液黏度和单孔进液速率对砾岩压裂裂缝动态扩展过程和压后裂缝宏观整体形态的影响规律.实验结果表明,砾岩压裂趋于在井筒处形成“纵向缝+横切缝”的复杂多裂缝形态,远离井筒后,横切主缝扩展优势逐步显现,局部遇砾形成分支缝;12 MPa高水平应力差条件下,压后近井区域形成多缝竞争扩展的复杂裂缝带,横切主缝向远端延伸优势减弱;压裂液黏度低于50 mPa·s时,压后横切主缝扩展优势显著,当压裂液黏度高于50 mPa·s时,近井区域形成复杂多裂缝形态;单孔进液速率超过0.3 m^(3)/min后,井筒处趋于形成多条纵向缝,易导致段间压窜.研究成果有助于深化认识砾岩储层压裂裂缝真实形态,为砾岩水力压裂方案设计提供理论指导.

关键词：油田开发致密砾岩矿场实验水力压裂裂缝扩展裂缝形态限流压裂

An adaptive loop gain selection for CLEAN deconvolution algorithm

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Research in Astronomy and Astrophysics 2019年第6期19卷 37-42页

作者： Li zhang long Xu Ming zhang Zhong-Zu Wu College of Big Data and Information Engineering Guizhou University Guiyang 550025 China Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences Beijing 100101 China Xinjiang Astronomical Observatory Chinese Academy of Sciences Urumqi 830011 China Key Laboratory of Radio Astronomy Chinese Academy of Sciences Urumqi 830011 China College of Physics Guizhou University Guiyang 550025 China

Radio interferometry significantly improves the resolution of observed images, and the final result also relies heavily on data recovery. The Cotton-Schwab CLEAN(CS-Clean) deconvolution approach is a widely used reconstruction algorithm in the field of radio synthesis imaging. However, parameter tuning for this algorithm has always been a difficult task. Here, its performance is improved by considering some internal characteristics of the data. From a mathematical point of view, a peak signal-to-noise-based(PSNRbased) method was introduced to optimize the step length of the steepest descent method in the recovery process. We also found that the loop gain curve in the new algorithm is a good indicator of parameter *** show that the new algorithm can effectively solve the problem of oscillation for a large fixed loop gain and provides a more robust recovery.

关键词： methods data analysis-techniques image processing-techniques interferometric

基于改进多尺度卷积循环神经网络的滚动轴承故障研究

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振动与冲击 2024年第20期43卷 94-105页

作者：董绍江黄翔夏宗佑邹松重庆交通大学机电与车辆工程学院重庆400074

针对传统卷积神经网络故障诊断方法提取特征不丰富,容易丢失故障敏感信息,且在单一尺度处理方法限制实际复杂工况下故障特性的深度挖掘问题,提出了注意力机制的多尺度卷积神经网络和双向长短期记忆(bi-directional long short-term memo... 详细信息

针对传统卷积神经网络故障诊断方法提取特征不丰富,容易丢失故障敏感信息,且在单一尺度处理方法限制实际复杂工况下故障特性的深度挖掘问题,提出了注意力机制的多尺度卷积神经网络和双向长短期记忆(bi-directional long short-term memory,BiLSTM)网络融合的迁移学习故障诊断方法。该方法首先应用不同尺寸池化层和卷积核捕获振动信号的多尺度特征;然后引入多头自注意力机制自动地给予特征序列中的不同部分不同的权重,进一步加强特征表示的能力;其次利用BiLSTM结构引入双向性质提取特征前后之间的内部关系实现信息的逐层传递;最后利用多核最大均值差异减小源域和目标域在预训练模型中各层上的概率分布差异并利用少量标记的目标域数据再对模型进行训练。试验结果表明,所提方法在江南大学(JNU)、德国帕德博恩大学(PU)公开轴承数据集上平均准确率分别为98.43%和97.66%,该方法在重庆长江轴承股份有限公司自制的轴承故障数据集上也表现出了极高的准确率和较快的收敛速度,为有效诊断振动旋转部件故障提供了实际依据。

关键词：故障诊断多尺度卷积神经网络双向长短期记忆(BiLSTM)网络多头自注意力多核最大均值差异

Cobalt nitride enabled benzimidazoles production from furyl/aryl bio-alcohols and o-nitroanilines without an external H-source

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Frontiers of Chemical Science and Engineering 2023年第1期17卷 68-81页

作者： Chuanhui Li Li-long zhang Hu Li Song Yang State Key Laboratory Breeding Base of Green Pesticide&Agricultural Bioengineering Key Laboratory of Green Pesticide&Agricultural BioengineeringMinistry of EducationState-Local Joint Laboratory for Comprehensive Utilization of BiomassCenter for R&D of Fine ChemicalsGuizhou UniversityGuiyang 550025China

Benzimidazole derivatives have wide-spectrum biological activities and pharmacological effects,but remain challenging to be produced from biomass ***,we report a green hydrogen transfer strategy for the efficient one-pot production of benzimidazoles from a wide range of bio-alcohols and o-nitroanilines enabled by cobalt nitride species on hierarchically porous and recyclable nitrogen-doped carbon catalysts(Co/CN_(x)-T,T denotes the pyrolysis temperature)without using an external hydrogen source and base *** the tested catalysts,Co/CN_(x)-700 exhibited superior catalytic performance,furnishing 2-substituted benzimidazoles in 65%–92%*** mechanistic studies manifest that the coordination between Co^(2+)and N with appropriate electronic state on the porous nitrogen-doped carbon having structural defects,as well as the remarkable synergetic effect of Co/N dual sites contribute to the pronounced activity of Co/CN_(x)-700,while too high pyrolysis temperature may cause the breakage of the catalyst Co-N bond to lower down its ***,it is revealed that the initial dehydrogenation of bio-alcohol and the subsequent cyclodehydrogenation are closely correlated with the hydrogenation of nitro *** catalytic hydrogen transfer-coupling protocol opens a new avenue for the synthesis of N-heterocyclic compounds from biomass.

关键词： biomass conversion furanic compounds benzimidazoles hydrogen transfer bifunctional catalysis

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鲁米诺电化学发光关键中间体的质谱在线表征

质谱学报 2024年第1期45卷 141-148,I0005页

作者：于凯乔志媛张铭旺朱乾龙刘吉林王雪凝余千云姜延晓张洪姜杰哈尔滨工业大学(威海)海洋科学与技术学院山东威海264209 哈尔滨工业大学化学化工学院黑龙江哈尔滨150001

鲁米诺优异的电化学发光性能使其在分析检测领域获得了广泛应用,然而,与反应机理相关的直接数据鲜有报道。本研究基于电化学-微米管-质谱(electrochemistry-micro tube-mass spectrometry,EC-MT-MS)技术,选用具有微米尖端的高硼硅玻璃... 详细信息

鲁米诺优异的电化学发光性能使其在分析检测领域获得了广泛应用,然而,与反应机理相关的直接数据鲜有报道。本研究基于电化学-微米管-质谱(electrochemistry-micro tube-mass spectrometry,EC-MT-MS)技术,选用具有微米尖端的高硼硅玻璃管作为电解池和质谱电喷雾离子源,通过内置2根铂金丝电极连接自制的电化学工作站,实现鲁米诺电化学发光反应的实时在线质谱分析,结合串联质谱技术确认了相关产物的分子结构。本工作发现了鲁米诺电化学反应的2种关键中间体以及发光产物3-氨基邻苯二甲酸,确认了过氧化氢对于鲁米诺发光反应的增益机制。此外,将1,4-苯醌加入鲁米诺-过氧化氢体系,验证了超氧根阴离子自由基(O^(·-)_(2),源于过氧化氢)在鲁米诺电发光反应过程中的核心作用,本实验结果为研究鲁米诺发光机理提供了直接的数据参考。

关键词：电化学-微米管-质谱(EC-MT-MS) 鲁米诺过氧化氢电化学发光 3-氨基邻苯二甲酸

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New Insight into Competition between Decomposition Pathways of Hydroperoxymethyl Formate in Low Temperature DME Oxidation

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Chinese Journal of Chemical Physics 2015年第5期28卷 -页

作者： Li-li Xing Xiao-yuan zhang Zhan-dong Wang Shuang Li Li-dong zhang National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei 230029 China

Hydroperoxymethyl formate is a crucial intermediate formed during the low-temperature oxidation of dimethyl ether. The decomposition pathways of HOOCH2OCHO were calculated at QCISD(T)/CBS//B3LYP/6-311++G(d,p) level. The temperature- and pressure-dependent rate constants are computed using microcanonical variational transition state theory coupled with the RRKM/master equation calculations. The calculations show that a pathway leads to the formation of formic acid and a Criegee intermediate does exist, besides the direct dissociation channel to OH and OCH2OCHO radicals. However, formation of the Criegee intermediate has never been considered as an intermediate in dimethyl ether combustion before. The computed rate constants indicate that the newly confirmed pathway is competitive to the direct dissociation route and it is promising to reduce the low-temperature oxidation reactivity. Also electronic effect of groups, e.g. -CHO and O atom, is taken into account. Moreover, Hirshfeld atomic charge and natural bond order analysis are performed to explain this phenomenon from a perspective of chemical nature.

关键词： Hydroperoxymethyl formate RRKM/master equation calculations Low temperature oxidation Dimethyl ether Chain branching

Interlayer material technology of manganese phosphate toward and beyond electrochemical pseudocapacitance over energy storage application

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Journal of Materials Science & Technology 2021年第12期71卷 109-128页

作者： Xu Bao Wei-Bin zhang Qiang zhang Lun zhang Xue-Jing Ma Jianping long College of Materials and Chemistry&Chemical Engineering Chengdu University of TechnologyChengdu 610059China

Manganese phosphates have shown excellent performances and great potential in electrochemical energy storage,which are demonstrated by research works published in recent *** manganese phosphates,the open-framework structures with large channels and cavities endow them with good ion conductivity and charge storage *** this review,we present the recent progress on manganese phosphates,by focusing on their advantages/disadvantages and potential applications as a new class of electrode materials in *** structural characteristics,synthesis methods,and mineral sources to prepare these manganese phosphates are investigated,together with the modification,as they strongly affect the electrochemical energy storage *** are paid to those hybrid-type materials,where strong synergistic effects *** the summary,interlayer engineering for the manganese phosphates and hybrid-types are proposed and discussed.

关键词： Manganese phosphate Layer structure Interlayer technology Pseudocapacitance Supercapacitor Energy storage