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Interactive Effects of Drought Stresses and Elevated CO_2 Concentration on Photochemistry Efficiency of Cucumber Seedlings

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Journal of Integrative Plant Biology 2008年第10期50卷 1307-1317页

作者： Qing-Ming Li Bin-Bin Liu Yang wu zhi-Rong Zou College of Horticulture Northwest A&F University Yangling 712100 China State Key Laboratory of Soil Erosion and Dryland Farming of the Loess Plateau Institute of Soil and Water Conservation the Chinese Academy of Sciences Yangling 712100 China College of Horticultural Science and Engineering Shandong Agricultural University Tai'an 271018 China

To reveal and quantify the interactive effects of drought stresses and elevated CO2 concentration [CO2] on photochemistry efficiency of cucumber seedlings, the portable chlorophyll meter was used to measure the chlorophyll content, and the Imaging-PAM was used to image the chlorophyll fluorescence parameters and rapid light response curves （RLC） of leaves in two adjacent greenhouses. The results showed that chlorophyll content of leaves was reduced significantly with drought stress aggravated. Minimal fluorescence （Fo） was increased while maximal quantum yield of PSII （Fv/Fm） decreased significantly by severe drought stress. The significant decrease of effective quantum yield of PSII （Y（Ⅱ）） accompanied by the significant increase of quantum yield of regulated energy dissipation （Y（NPQ）） was observed under severe drought stress condition, but there was no change of quantum yield of nonregulated energy dissipation （Y（NO））. We detected that the coefficient of photochemical quenching （qP） decreased, and non-photochemical quenching （NPQ） increased significantly under severe drought stress. Furthermore, we found that maximum apparent electron transport rate （ETRmax） and saturating photosynthetically active radiation （PPFDsat） decreased significantly with drought stress aggravated. However, elevated [CO2] significantly increased FvlFm, qP and PPFDsat, and decreased NPQ under all water conditions, although there were no significant effects on chlorophyll content, Fo, Y（Ⅱ）, Y（NPQ）, Y（NO） and ETRmax. Therefore, it is concluded that CO2-fertilized greenhouses or elevated atmospheric [CO2] in the future could be favorable for cucumber growth and development, and beneficial to alleviate the negative effects of drought stresses to a certain extent.

关键词： chlorophyll fluorescence cucumber seedlings drought stresses elevated CO2 concentration photochemistry efficiency.

Abnormal immunity of non-survivors with COVID-19: predictors for mortality

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Infectious Diseases of Poverty 2020年第4期9卷 159-160页

作者： Yang Zhao Han-Xiang Nie Ke Hu xiao-Jun wu Yun-Ting Zhang Meng-Mei Wang Tao Wang zhi-Shui Zheng xiao-Chen Li Shao-Lin Zeng Department of Respiratory Medicine Renmin Hospital of Wuhan University238 Jiefang RoadWuchang DistrictWuhan430060China

Background The number of coronavirus disease 2019(COVID-19)cases has rapidly increased all over the *** information about immunity in non-survivors with COVID-19 is *** study aimed to analyse the clinical characteristics and abnormal immunity of the confirmed COVID-19 *** In this single-centered,retrospective,observational study,we enrolled 125 patients with COVID-19 who were died between January 13 and March 4,2020 in Renmin Hospital of wuhan University.A total of 414 randomly recruited patients with confirmed COVID-19 who were discharged from the same hospital during the same period served as *** demographic,clinical characteristics and laboratory findings at admission,and treatment used in these patients were *** immunity-related risk factors associated with in-hospital death were tested by logistic regression models and Receiver Operating Characteristic(ROC)*** Non-survivors(70 years,IQR:61.5–80)were significantly older than survivors(54 years,IQR:37–65)(P<0.001).56.8%of non-survivors was *** half of the patients(44.9%)had chronic medical *** non-survivors,hypertension(49.6%)was the most common comorbidity,followed by diabetes(20.0%)and coronary heart disease(16.0%).The common signs and symptoms at admission of non-survivors were fever(88%),followed by cough(64.8%),dyspnea(62.4%),fatigue(62.4%)and chest tightness(58.4%).Compared with survivors,non-survivors had higher white blood cell(WBC)count(7.85 vs 5.07×109/L),more elevated neutrophil count(6.41 vs 3.08×109/L),smaller lymphocyte count(0.69 vs 1.20×109/L)and lower platelet count(172 vs 211×109/L),raised concentrations of procalcitonin(0.21 vs 0.06 ng/mL)and CRP(70.5 vs 7.2 mg/L)(P<0.001).This was accompanied with significantly decreased levels of CD3+T cells(277 vs 814 cells/μl),CD4+T cells(172 vs 473 cells/μl),CD8+T cells(84 vs 262.5 cells/μl,P<0.001),CD19+T cells(88 vs 141 cells/μl)and CD16+56+T cells(79 vs 128.5 cells/μl)(P<0.0

关键词： COVID-19 Cellular immunity Humoral immunity Mortality

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基于卷积自编码器的座椅电机故障诊断

声学技术 2024年第3期43卷 417-425页

作者：王龙祥朱亚伟卢炽华刘志恩肖文浩谢丽萍武汉理工大学现代汽车零部件技术湖北省重点实验室湖北武汉430070 佛山仙湖实验室工业软件与仿真技术实验室广东佛山528200

故障数据的缺失一直是制约设备故障诊断发展的重要因素,现有研究通过刻意损坏设备的方法来采集故障数据。为实现座椅电机的无损故障诊断,文章对座椅电机的故障机理进行分析,确定可能发生的故障类型,通过在座椅电机表面粘贴微型喇叭并播... 详细信息

故障数据的缺失一直是制约设备故障诊断发展的重要因素,现有研究通过刻意损坏设备的方法来采集故障数据。为实现座椅电机的无损故障诊断,文章对座椅电机的故障机理进行分析,确定可能发生的故障类型,通过在座椅电机表面粘贴微型喇叭并播放故障声音,来模拟故障的发生。在自编码器系统的基础上,引入卷积操作,使用卷积层代替全连接层,通过输入数据维度、卷积核的尺寸和数量以及池化、正则化等操作对模型结构进行调整。采用IDMT Isa Electric Engine数据集作为源域数据,对模型进行预训练。使用迁移学习方法将源域中已经学习到的数据分布迁移到座椅电机故障诊断任务中,并与各类模型检测结果进行对比。结果显示,文中方法在召回率保持1.00的情况下,曲线下面积达到0.86,检测结果可靠,具有实际应用价值。

关键词：卷积自编码器无监督学习模拟故障声音迁移学习

肝肠胞虫对凡纳滨对虾肠道和肝胰腺菌群的影响

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水生生物学报 2024年第2期48卷 315-323页

作者：李舢舢赵晨曦吴波郑侠飞戴文芳林志华柳敏海浙江万里学院宁海海洋生物种业研究院浙江省水产种质资源高效利用技术研究重点实验室宁波315000

利用16S rRNA高通量测序对比研究了健康对虾和感染肝肠胞虫的发病对虾肠道及肝胰腺菌群的组成、多样性、微生物介导的功能和种间互作间的差异性。结果表明,健康对虾的肠道和肝胰腺细菌群落的多样性高于发病对虾。在属水平上,健康对虾和... 详细信息

利用16S rRNA高通量测序对比研究了健康对虾和感染肝肠胞虫的发病对虾肠道及肝胰腺菌群的组成、多样性、微生物介导的功能和种间互作间的差异性。结果表明,健康对虾的肠道和肝胰腺细菌群落的多样性高于发病对虾。在属水平上,健康对虾和发病对虾的肠道及肝胰腺中的优势细菌组成及丰度存在明显不同,其中健康对虾肠道中的优势菌属主要为埃希杆菌-志贺菌属(Escherichia-Shigella)和海绵菌属(Spongiimonas),而发病对虾肠道中的优势菌属则为希瓦式菌属(Shewanella)、巨球型菌属(Megasphaera)和克雷伯氏菌属(Klebsiella);健康对虾肝胰腺中的优势菌属主要为假单胞菌属(Pseudomonas)和汉氏盐单胞菌(Halomonas),而发病对虾肝胰腺中的优势菌属则为贪铜菌属(Cupriavidus)。Tax4Fun2预测显示,健康对虾肠道和肝胰腺菌群的主要功能分别与发病对虾肠道和肝胰腺菌群的主要功能有明显差异。研究有助于了解肝肠胞虫对凡纳滨对虾肠道及肝胰腺细菌群落的影响,并为凡纳滨对虾的健康管理和养殖提供依据。

关键词：肠道菌群 16S rRNA测序功能预测凡纳滨对虾

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常规公交运营脆弱性评价及发车优化研究

公路交通科技 2024年第6期41卷 173-181页

作者：胡立伟武加宝赵雪亭杨志莹余先林昆明理工大学交通工程学院云南昆明650500

针对常规公交在城市公共交通中的分担率逐年下降状况,综合考量乘客的出行感知和公交运营成本,为量化常规公交运营线路的脆弱性并提高服务质量,提出了常规公交运营脆弱性评价方法及其基于脆弱性评价的的公交发车间隔优化。首先,采用文献... 详细信息

针对常规公交在城市公共交通中的分担率逐年下降状况,综合考量乘客的出行感知和公交运营成本,为量化常规公交运营线路的脆弱性并提高服务质量,提出了常规公交运营脆弱性评价方法及其基于脆弱性评价的的公交发车间隔优化。首先,采用文献萃取法从人为活动、运营组织管理、环境状态和车辆状态4个方面萃取得到15个脆弱因子,基于概念格加权群组改进的结构解释模型对初始评分结果进行统计筛选得到脆弱因子间的影响程度关系,通过对脆弱因子的暴露性、敏感性和适应性3个特征进行等级划分,以取交集的方法得到车内拥挤度和候车时长2个关键脆弱因子。其次,从不同客流时段的乘客感知与心理变化特征角度出发,对车内拥挤度的等级划分和候车时长正态分布曲线进行分析,确定拥挤度的临界划分和以85%乘客的候车容忍时间作为容忍阈值。进一步,基于关键脆弱因子及其容忍阈值构建高峰、次高峰和平峰时段以发车间隔时间为变量的运营公司成本和乘客成本函数模型,并采用遗传算法进行求解。最后,结合昆明市23路公交线路进行算例分析。结果表明:优化后的运营线路高峰时段的暴露度、敏感度和适应度分别降低39.10%,26.75%,35.74%,脆弱度降低了33.88%,优化效果最好,次高峰居中,平峰较差。总体分析来看,评价模型和优化方法具有较好的实用性,提升了乘客出行感知服务水平并降低了运营成本。

关键词：智能交通脆弱性评价改进ISM 常规公交运营发车间隔优化遗传算法

Microfluidic assisted 90%loading CL-20 spherical particles:Enhancing self-sustaining combustion performance

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Defence Technology（防务技术） 2023年第4期22卷 176-184页

作者： Ling-feng Yang Xian-rui Shi Chun-zhi Li Bo wu Chong-hua Pei State Key Laboratory of Environment-friendly Energy Materials Southwest University of Science and TechnologyMianyang621010PR China Xi'an Modern Chemistry Research Institute Xi'anShaanxi710065PR China Luzhou North Chemical Industries Co. Ltd.Luzhou646003PR China

The performance of the chemical fuel determines the altitude,range and longevity of spacecraft in air and space *** alternatives(e.g.,hypergolic ionic liquids or high-energy composites)with high-energy density,heat of formation and fast initial rate are considered as potential chemical *** the high-energy density material,hexanitrohexaazaisowurtzitane(CL-20)often serves as secondary explosive with poor self-propagating combustion ***,90%loading CL-20 microspheres with uniform particle sizes are precisely prepared by microfluid method,which exhibit unique hierarchical *** morphology,thermal behaviors,as well as combustion performance were further *** results demonstrated that as-prepared spherical particles exhibit prominent thermal compatibility,and the enhanced self-sustaining combustion *** work provides an efficient method achieving the uniform high-energy density particles with excellent self-sustaining combustion performance.

关键词： Microfluidics Hexanitrohexaazaisowurtzitane Spherical particles Thermal behavior Self-sustaining combustion

Mainchain Semifluorinated Polymers with Ultra High Molecular Weight via Reaction-enhanced Reactivity of Intermediate(RERI) Mechanism

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Chinese Journal of Polymer Science 2023年第5期41卷 760-767,I0009页

作者： Jia-Sheng wu Wang-Meng Hou zhi-Jia Liu Yi Shi Yong-Ming Chen School of Materials Science and Engineering Key Laboratory for Polymeric Composite and Functional Materials of Ministry of EducationSun Yat-Sen UniversityGuangzhou 510006China

Achieving the linear polymers with high molecular weight via step-growth polymerization of A2 and B2 monomers is significantly limited by the requirement of strict stoichiometry of two monomers when the reactivity of A and B groups are not changed during the ***,a unique step-growth polymerization based on copper-catalyzed azide-alkyne cycloaddition(CuAAC)with reactionenhanced reactivity of intermediate(RERI)mechanism was developed for the preparation of mainchain semifluorinated polymers with high molecular *** CuAAC polymerization of bis-alkynyl-terminated fluorinated monomers(A2)and 2,2-bis(azidomethyl)propane-1,3-diyl bis(2-methylpropanoate)(BiAz,B2)with RERI effect at different stoichiometric ratio was systematically *** results indicated that the semifluorinated polymers with ultrahigh molecular weight,Mw,MALLS>106 g/mol,could be efficiently synthesized by using excess molar of BiAz *** resultant high-molecular-weight semifluorinated polymers show good thermostability and high *** addition,the glass transition temperature(Tg)of these mainchain semifluorinated polymers could be tuned conveniently due to the bis-alkynyl-terminated comonomers could be consumed completely when excessive BiAz monomers were used in this this step-growth polymerization.

关键词： Semifluorinated polymers Click polymerization Step-growth polymerization

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辣椒CaPI的克隆与功能分析

生物技术通报 2024年第3期40卷 193-201页

作者：吴星星洪海波甘志承李瑞宁黄先忠安徽科技学院农学院作物生物技术研究中心滁州233100

【目的】PISTILLATA(PI)基因属于典型的Type II型MADS-box基因家族成员,是ABC(D)E模型中的B类基因,在植物发育过程中起着重要作用,但辣椒PI同源基因功能研究未见报道。探索辣椒PI基因功能,为深入研究植物PI同源基因的功能机制奠定基础... 详细信息

【目的】PISTILLATA(PI)基因属于典型的Type II型MADS-box基因家族成员,是ABC(D)E模型中的B类基因,在植物发育过程中起着重要作用,但辣椒PI同源基因功能研究未见报道。探索辣椒PI基因功能,为深入研究植物PI同源基因的功能机制奠定基础。【方法】利用RT-PCR的方法从一年生辣椒(Capsicum annuum L.)花器官的cDNA中克隆PI同源基因CaPI,并通过生物信息学方法分析其理化性质、亚细胞定位、蛋白结构和系统进化关系;利用实时荧光定量PCR(RT-qPCR)技术分析基因在辣椒不同组织中的表达特征;构建植物过表达载体35S:CaPI,通过floral-dipping法转化拟南芥。【结果】该基因开放阅读框648 bp,编码215个氨基酸,相对分子质量为25.13 kD。氨基酸多重序列比对表明,CaPI蛋白N端含有“MGRGKIEIKRIEN”保守基序。系统进化树分析证实,CaPI与马铃薯、番茄和矮牵牛的PI同源基因亲缘关系较近。RT-qPCR证实CaPI主要在花中表达,在花萼中表达量最高,其次是花瓣,在雄蕊中低表达,而在雌蕊中几乎不表达。在拟南芥中过表达CaPI,与野生型拟南芥(Col-0)相比,35S:CaPI转基因植株表现出莲座叶和分枝数量增多等表型,但不影响花器官的发育。【结论】辣椒CaPI具有促进植物分枝发育的功能。

关键词： CaPI 辣椒 MADS-box 基因表达

Endogenous hydrogen sulfide and ERK1/2-STAT3 signaling pathway may participate in the association between homocysteine and hypertension

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Journal of Geriatric Cardiology 2019年第11期16卷 822-834页

作者： Lin SHI xiao-Yun LIU zhi-Gang HUANG zhi-Yi MA Yang XI Lu-Yan WANG Ning-Ling SUN Hypertension Research Laboratory Department of CardiologyPeking University People’s HospitalBeijingChina Emergency Department Peking University Shenzhen HospitalShenzhenChina

Background Homocysteine(Hcy)is a risk factor for hypertension,although the mechanisms are poorly *** We first explored the relationship between Hcy levels and blood pressure(BP)by analyzing the clinical data of primary hypertensive patients admitted to our ***,we explored a rat model to study the effect of Hcy on blood pressure and the role of *** hyperhomocysteinemia(HHcy)rat model was induced to explore the effect of Hcy on blood pressure and the possible *** carried out tissue histology,extraction and examination of RNA and ***,we conducted cell experiments to determine a likely mechanism through renin-angiotensin-aldosterone system(RAAS)and extracellular signal-regulated kinase 1/2(ERK1/2)signaling *** In primary hypertensive inpatients with HHcy,blood pressure was significantly higher as compared with inpatient counterparts lacking *** the rat model,blood pressure of the Wistar rats was significantly increased with increases in serum Hcy levels and decreased after folate *** converting enzyme 1(ACE1)expression in the Wistar Hcy group was enhanced comparing to controls,but was decreased in the Wistar folate *** II receptor type 1(AGTR1)levels in the kidney tissue increased in the Wistar folate *** serum H2S and kidney cystathionineγ-lyase decreased with elevated levels of serum *** vitro,increased concentrations and treatment times for Hcy were associated with increased expression of collagen type 1 and *** dose and time dependent response was also observed for p-STAT3 and p-ERK1/2 *** Endogenous H2S might mediate the process of altered blood pressure in response to changes in serum Hcy levels,in a process that is partly dependent on activated RAAS and ERK1/2-STAT3 signaling pathway.

关键词： Angiotensin converting enzyme 1 Blood pressure ERK1/2-STAT3 signaling pathway Homocysteine Hydrogen sulfide