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Passivity-Based Robust Control Against Quantified False Data Injection Attacks in Cyber-Physical Systems 被引量:2
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作者 Yue Zhao Ze Chen +2 位作者 Chunjie Zhou Yu-Chu Tian Yuanqing Qin 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第8期1440-1450,共11页
Secure control against cyber attacks becomes increasingly significant in cyber-physical systems(CPSs).False data injection attacks are a class of cyber attacks that aim to compromise CPS functions by injecting false d... Secure control against cyber attacks becomes increasingly significant in cyber-physical systems(CPSs).False data injection attacks are a class of cyber attacks that aim to compromise CPS functions by injecting false data such as sensor measurements and control signals.For quantified false data injection attacks,this paper establishes an effective defense framework from the energy conversion perspective.Then,we design an energy controller to dynamically adjust the system energy changes caused by unknown attacks.The designed energy controller stabilizes the attacked CPSs and ensures the dynamic performance of the system by adjusting the amount of damping injection.Moreover,with the disturbance attenuation technique,the burden of control system design is simplified because there is no need to design an attack observer.In addition,this secure control method is simple to implement because it avoids complicated mathematical operations.The effectiveness of our control method is demonstrated through an industrial CPS that controls a permanent magnet synchronous motor. 展开更多
关键词 Cyber-physical systems energy controller energy conversion false data injection attacks l2 disturbance attenuation technology
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Liquefaction of metal-contaminated giant reed biomass in acidified ethylene glycol system:Batch experiments
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作者 郭朝晖 刘亚男 +1 位作者 王凤永 肖细元 《Journal of Central South University》 SCIE EI CAS 2014年第5期1756-1762,共7页
Giant reed is a suitable pioneer plant for metal-contaminated soil phytoremediation,however,it is imperative to dispose the metal-contaminated biomass after harvesting.The liquefaction of metal-contaminated giant reed... Giant reed is a suitable pioneer plant for metal-contaminated soil phytoremediation,however,it is imperative to dispose the metal-contaminated biomass after harvesting.The liquefaction of metal-contaminated giant reed biomass in ethylene glycol system with sulfuric acid as catalyst for the precursors of polyurethane compounds was studied.The results show that giant reed biomass from metal-contaminated soil is potentially liquefied and significantly affected by solvent/solid ratio,liquefaction temperature and liquefaction time (P〈0.05).The liquefaction rate of biomass in acidified ethylene glycol system can reach 85.2% with optimized conditions of 60 min,170 ℃,3% sulfuric acid and solvent/biomass ratio of 5:1.The hydroxyl value of liquefied products is of 481 mg KOH/g while reactive hydroxyl groups of them are abundant,which is promised as potential precursors for polyurethane compounds.The solvent liquefaction is a potential method to dispose the metal-contaminated biomass,however,the containing-metal liquefied products should be studied deeply in order to get the suitable precursors in future. 展开更多
关键词 Arundo donax l. metal-contaminated biomass solvent liquefaction PHYTOREMEDIATION
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GLOBAL EXISTENCE FOR A SEMILINEAR DIFFERENTIAL SYSTEM
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作者 LI SHUANHU 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1995年第4期387-398,共12页
In this paper, a semilinear elliptic-parabolic PDE system which arises in a two dimensional groundwater flow problem is studied. Existence and uniqueness results are established via the L ̄p - L ̄q a priori estimates ... In this paper, a semilinear elliptic-parabolic PDE system which arises in a two dimensional groundwater flow problem is studied. Existence and uniqueness results are established via the L ̄p - L ̄q a priori estimates and the inverse function theorem. 展开更多
关键词 l ̄p - l ̄q estimates UNIQUENESS existence.
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Detecting physical laws from data of stochastic dynamical systems perturbed by non-Gaussianα-stable Lévy noise
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作者 陆凌弘志 李扬 刘先斌 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期337-342,共6页
Massive data from observations,experiments and simulations of dynamical models in scientific and engineering fields make it desirable for data-driven methods to extract basic laws of these models.We present a novel me... Massive data from observations,experiments and simulations of dynamical models in scientific and engineering fields make it desirable for data-driven methods to extract basic laws of these models.We present a novel method to identify such high dimensional stochastic dynamical systems that are perturbed by a non-Gaussianα-stable Lévy noise.More explicitly,firstly a machine learning framework to solve the sparse regression problem is established to grasp the drift terms through one of nonlocal Kramers–Moyal formulas.Then the jump measure and intensity of the noise are disposed by the relationship with statistical characteristics of the process.Three examples are then given to demonstrate the feasibility.This approach proposes an effective way to understand the complex phenomena of systems under non-Gaussian fluctuations and illuminates some insights into the exploration for further typical dynamical indicators such as the maximum likelihood transition path or mean exit time of these stochastic systems. 展开更多
关键词 data-driven modelling noise-induced transitions lévy noise Kramers–Moyal formuas
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Antioxygenic Activity of <i>Solanum nigrum L.</i>Leaves in Sunflower Oil Model System and Its Thermal Stability
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作者 Ananthan Padmashree Gopal Kumar Sharma +1 位作者 Anil Dutt Semwal Chitrashekarachar Mahesh 《Food and Nutrition Sciences》 2014年第11期1022-1029,共8页
The antioxygenic activity of Solanum nigrum L. leaves and its various solvent extracts were evaluated using sunflower oil model system. Leaf powder and its methanol/water (80:20) soluble fraction showed strong antioxy... The antioxygenic activity of Solanum nigrum L. leaves and its various solvent extracts were evaluated using sunflower oil model system. Leaf powder and its methanol/water (80:20) soluble fraction showed strong antioxygenic activity in refined sunflower oil. On the other hand, ethyl acetate fraction exhibited marginal antioxygenic activity, whereas the water soluble fraction was practically devoid of any activity in refined sunflower oil. Thermal stability of different extracts of Solanum nigrum L. leaves heated at 80?C in refined sunflower oil also indicated the strong efficacy of methanol/water (80:20) extract to inhibit thermal oxidation. Solanum nigrum L. contain high levels of magnesium (239.0 mg/100g) and phosphorous (80.3 mg/100g). Fatty acid analysis of the lipid extracted from Solanum nigrum L. leaves indicated the presence of linoleic (59.1%) as a major fatty acid. The result of this study confirmed the presence of antioxygenic compounds in leaves, in particular its methanol/water (80:20) extracts showed great potential as a natural antioxidant to inhibit lipid peroxidation in foods. 展开更多
关键词 SOlANUM nigrum l. Antioxygenic ACTIVITY Solvent Extraction Thermal Stability Phenolics FlAVONOIDS
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Features of Electrochemical and Conformational Behavior of Intergel System Based on Polyacrylic Acid and Poly-4-Vinylpyridine Hydrogels in an Aqueous Medium
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作者 Jumadilov Talkybek Kozhataevich Himersen Huangul Kaldayeva Saltanat Serikovna Kondaurov Ruslan Gennadievich 《材料科学与工程(中英文B版)》 2014年第6期147-151,共5页
关键词 聚4-乙烯基吡啶 聚丙烯酸 水凝胶 l系统 电化学 构象 水介质 特征
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基于自由曲面和L-system的红掌生长模型
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作者 邹一波 褚诗贤 +1 位作者 葛艳 陈明 《湖南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期85-90,共6页
针对红掌花卉生长可视化中参数难以确定的问题进行研究,提出推导控制点的方法,建立红掌器官模型:采用Bezier曲线结合扫描成型的方法来构造叶柄模型,采用双三次NURBS曲线对佛焰苞进行建模;运用红掌的相关表型数据拟合生长函数,提出基于... 针对红掌花卉生长可视化中参数难以确定的问题进行研究,提出推导控制点的方法,建立红掌器官模型:采用Bezier曲线结合扫描成型的方法来构造叶柄模型,采用双三次NURBS曲线对佛焰苞进行建模;运用红掌的相关表型数据拟合生长函数,提出基于红掌生长规律的微分L-system,可有效模拟红掌的拓扑结构和生长过程;通过虚拟器官表示红掌器官的几何属性,降低微分L-system的复杂度。试验验证提出的方法对红掌各项生长指标拟合度可达0.89以上,并可对每个生长阶段的红掌进行模拟,能有效地对红掌的生长过程进行建模。 展开更多
关键词 红掌 自由曲面建模 l-system 生长函数 虚拟器官
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缺血性脑卒中铁死亡特征基因NFE2L2的鉴定与验证
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作者 王咪 马书杰 +1 位作者 刘杨 齐瑞 《中国组织工程研究》 CAS 北大核心 2025年第7期1466-1474,共9页
背景:铁死亡与缺血性脑卒中的发病密切相关,靶向铁死亡是一种治疗缺血性脑卒中有前景的方案,但具体调控靶点尚不明确。目的:通过生物信息学和机器学习方法筛选缺血性脑卒中铁死亡相关特征基因,并通过细胞实验进行验证,探讨铁死亡在缺血... 背景:铁死亡与缺血性脑卒中的发病密切相关,靶向铁死亡是一种治疗缺血性脑卒中有前景的方案,但具体调控靶点尚不明确。目的:通过生物信息学和机器学习方法筛选缺血性脑卒中铁死亡相关特征基因,并通过细胞实验进行验证,探讨铁死亡在缺血性脑卒中的作用。方法:基于GEO数据库和FerrDb数据库选取符合条件的缺血性脑卒中相关数据集和铁死亡表达数据集,通过t检验筛选铁死亡相关差异基因。对铁死亡相关差异基因进行GO功能富集分析与KEGG信号通路富集分析。通过PPI网络分析和机器学习筛选缺血性脑卒中铁死亡的特征基因,利用ROC分析和GSEA分析探究特征基因的准确性和生物功能。然后进行细胞实验,将HT22细胞分为对照组与缺血性脑卒中组,对照组不作任何干预,缺血性脑卒中组加入0.1 mol/L的H_(2)O_(2)干预24 h诱导细胞氧化应激和铁死亡,通过实时荧光定量RT-PCR和Western Blot验证铁死亡的发生和特征基因表达。结果与结论:(1)共获取45个铁死亡相关差异基因,GO和KEGG富集分析发现差异基因与氧化应激、自噬、铁死亡、脂肪细胞因子信号通路和线粒体代谢密切相关。(2)通过PPI网络中的MCODE插件和cytoHubba插件与机器学习中的LASSO算法和SVM-RFE算法共鉴定出1个铁死亡特征基因核因子E2相关因子2(nuclear factor erythroid 2-related factor 2,NFE2L2)。(3)对NFE2L2进行ROC曲线分析,发现在训练集和验证集中构建的诊断预测模型具有良好的准确性与特异性;对NFE2L2进行GSEA分析,发现特征基因通过免疫、炎症反应、氨基酸代谢及神经因子调控等方面参与缺血性脑卒中发病机制的调控。(4)细胞实验的RT-PCR和Western Blot分析表明,与对照组对比,缺血性脑卒中组中的酰基辅酶A合成酶长链家族成员4 mRNA和蛋白表达水平显著增高(P<0.05),谷胱甘肽过氧化物酶4 mRNA和蛋白表达水平显著降低(P<0.05);与对照组对比,缺血性脑卒中组中特征基因NFE2L2 mRNA和蛋白表达水平显著增高(P<0.05)。(5)上述结果证实,缺血性脑卒中与铁死亡密切相关,靶向特征基因NFE2L2可以为研究和治疗缺血性脑卒中提供一定的思路与方向。 展开更多
关键词 缺血性脑卒中 铁死亡 生物信息学 HT22细胞 机器学习 特征基因 细胞实验 NFE2l2 ASCl4 GPX4
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Effects of P301L-TAU on post-translational modifications of microtubules in human iPSC-derived cortical neurons and TAU transgenic mice
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作者 Mohamed Aghyad Al Kabbani Christoph Köhler Hans Zempel 《Neural Regeneration Research》 SCIE CAS 2025年第8期2348-2360,共13页
TAU is a microtubule-associated protein that promotes microtubule assembly and stability in the axon.TAU is missorted and aggregated in an array of diseases known as tauopathies.Microtubules are essential for neuronal... TAU is a microtubule-associated protein that promotes microtubule assembly and stability in the axon.TAU is missorted and aggregated in an array of diseases known as tauopathies.Microtubules are essential for neuronal function and regulated via a complex set of post-translational modifications,changes of which affect microtubule stability and dynamics,microtubule interaction with other proteins and cellular structures,and mediate recruitment of microtubule-severing enzymes.As impairment of microtubule dynamics causes neuronal dysfunction,we hypothesize cognitive impairment in human disease to be impacted by impairment of microtubule dynamics.We therefore aimed to study the effects of a disease-causing mutation of TAU(P301L)on the levels and localization of microtubule post-translational modifications indicative of microtubule stability and dynamics,to assess whether P301L-TAU causes stability-changing modifications to microtubules.To investigate TAU localization,phosphorylation,and effects on tubulin post-translational modifications,we expressed wild-type or P301L-TAU in human MAPT-KO induced pluripotent stem cell-derived neurons(i Neurons)and studied TAU in neurons in the hippocampus of mice transgenic for human P301L-TAU(p R5 mice).Human neurons expressing the longest TAU isoform(2N4R)with the P301L mutation showed increased TAU phosphorylation at the AT8,but not the p-Ser-262 epitope,and increased polyglutamylation and acetylation of microtubules compared with endogenous TAU-expressing neurons.P301L-TAU showed pronounced somatodendritic presence,but also successful axonal enrichment and a similar axodendritic distribution comparable to exogenously expressed 2N4R-wildtype-TAU.P301L-TAU-expressing hippocampal neurons in transgenic mice showed prominent missorting and tauopathy-typical AT8-phosphorylation of TAU and increased polyglutamylation,but reduced acetylation,of microtubules compared with non-transgenic littermates.In sum,P301L-TAU results in changes in microtubule PTMs,suggestive of impairment of microtubule stability.This is accompanied by missorting and aggregation of TAU in mice but not in i Neurons.Microtubule PTMs/impairment may be of key importance in tauopathies. 展开更多
关键词 human induced pluripotent stem cell MICROTUBUlES P301l pR5 mice TAU TAUOPATHY tubulin code
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Recombinant chitinase-3-like protein 1 alleviates learning and memory impairments via M2 microglia polarization in postoperative cognitive dysfunction mice
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作者 Yujia Liu Xue Han +6 位作者 Yan Su Yiming Zhou Minhui Xu Jiyan Xu Zhengliang Ma Xiaoping Gu Tianjiao Xia 《Neural Regeneration Research》 SCIE CAS 2025年第9期2727-2736,共10页
Postoperative cognitive dysfunction is a seve re complication of the central nervous system that occurs after anesthesia and surgery,and has received attention for its high incidence and effect on the quality of life ... Postoperative cognitive dysfunction is a seve re complication of the central nervous system that occurs after anesthesia and surgery,and has received attention for its high incidence and effect on the quality of life of patients.To date,there are no viable treatment options for postoperative cognitive dysfunction.The identification of postoperative cognitive dysfunction hub genes could provide new research directions and therapeutic targets for future research.To identify the signaling mechanisms contributing to postoperative cognitive dysfunction,we first conducted Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of the Gene Expression Omnibus GSE95426 dataset,which consists of mRNAs and long non-coding RNAs differentially expressed in mouse hippocampus3 days after tibial fracture.The dataset was enriched in genes associated with the biological process"regulation of immune cells,"of which Chill was identified as a hub gene.Therefore,we investigated the contribution of chitinase-3-like protein 1 protein expression changes to postoperative cognitive dysfunction in the mouse model of tibial fractu re surgery.Mice were intraperitoneally injected with vehicle or recombinant chitinase-3-like protein 124 hours post-surgery,and the injection groups were compared with untreated control mice for learning and memory capacities using the Y-maze and fear conditioning tests.In addition,protein expression levels of proinflammatory factors(interleukin-1βand inducible nitric oxide synthase),M2-type macrophage markers(CD206 and arginase-1),and cognition-related proteins(brain-derived neurotropic factor and phosphorylated NMDA receptor subunit NR2B)were measured in hippocampus by western blotting.Treatment with recombinant chitinase-3-like protein 1 prevented surgery-induced cognitive impairment,downregulated interleukin-1βand nducible nitric oxide synthase expression,and upregulated CD206,arginase-1,pNR2B,and brain-derived neurotropic factor expression compared with vehicle treatment.Intraperitoneal administration of the specific ERK inhibitor PD98059 diminished the effects of recombinant chitinase-3-like protein 1.Collectively,our findings suggest that recombinant chitinase-3-like protein 1 ameliorates surgery-induced cognitive decline by attenuating neuroinflammation via M2 microglial polarization in the hippocampus.Therefore,recombinant chitinase-3-like protein1 may have therapeutic potential fo r postoperative cognitive dysfunction. 展开更多
关键词 Chil1 hippocampus learning and memory M2 microglia NEUROINFlAMMATION postoperative cognitive dysfunction(POCD) recombinant CHI3l1
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载富血小板血浆水凝胶对L929细胞氧化损伤的保护作用
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作者 王自林 牟秋菊 +2 位作者 刘宏杰 申玉雪 祝丽丽 《中国组织工程研究》 CAS 北大核心 2025年第4期771-779,共9页
背景:在慢性创面愈合过程中,活性氧的过量生成可能会损害L929成纤维细胞的功能,从而延缓创面修复,因此保护成纤维细胞免受氧化应激的影响对于促进创面愈合非常重要。目的:评估羧甲基壳聚糖-氧化硫酸软骨素/富血小板血浆(CMC-OCS/PRP)水... 背景:在慢性创面愈合过程中,活性氧的过量生成可能会损害L929成纤维细胞的功能,从而延缓创面修复,因此保护成纤维细胞免受氧化应激的影响对于促进创面愈合非常重要。目的:评估羧甲基壳聚糖-氧化硫酸软骨素/富血小板血浆(CMC-OCS/PRP)水凝胶对H2O2刺激下L929细胞的保护作用。方法:制备CMC-OCS/PRP水凝胶,表征水凝胶的微观形貌、降解性能、清除H2O2与羟基自由基的能力及生物相容性。取生长状态良好的L929细胞,分5组培养:对照组常规培养,H2O2组加入H2O2,CMC-OCS组加入羧甲基壳聚糖-氧化硫酸软骨素水凝胶浸提液+H2O2,PRP组加入富血小板血浆凝胶浸提液+H2O2,CMC-OCS/PRP组加入羧甲基壳聚糖-氧化硫酸软骨素/富血小板血浆水凝胶浸提液处理+H2O2,每组先加入水凝胶浸提液处理6 h,然后再加入H2O2处理24 h。培养结束后,检测细胞活性氧及丙二醛水平,细胞凋亡、胶原纤维Ⅰ蛋白表达。在加入H2O2的情况下,将上述水凝胶浸提液分别与L929成纤维细胞直接或间接共培养36 h,通过划痕实验、Transwell小室实验检测细胞的迁移能力。结果与结论:①CMC-OCS/PRP水凝胶具有均匀相互关联的多孔结构及良好的降解能力,体外可有效清除H2O2与羟基自由基,并且具有良好的生物相容性;②与对照组比较,H2O2组细胞凋亡率、细胞活性氧与丙二醛水平升高(P<0.05),细胞铺展面积减少(P<0.05),胶原纤维Ⅰ蛋白表达无明显变化(P>0.05);与H2O2组比较,CMC-OCS组、CMC-OCS/PRP组细胞活性氧水平降低(P<0.05),PRP组、CMC-OCS组、CMCOCS/PRP组丙二醛水平降低(P<0.05)、细胞铺展面积增加(P<0.05),CMC-OCS/PRP组细胞凋亡率降低(P<0.05),PRP组、CMC-OCS组、CMCOCS/PRP组胶原纤维Ⅰ蛋白表达增加(P<0.05);③与对照组比较,H2O2组细胞迁移数量减少(P<0.05),迁移面积无明显变化(P>0.05);与H2O2组比较,PRP组、CMC-OCS组、CMC-OCS/PRP组细胞迁移数量、迁移面积均增加(P<0.05),并且以CMC-OCS/PRP组增加最显著;④在氧化应激条件下,CMC-OCS/PRP水凝胶可改善成纤维细胞的迁移能力,抗细胞凋亡并保护细胞伸展功能。 展开更多
关键词 富血小板血浆 羧甲基壳聚糖 氧化硫酸软骨素 水凝胶 l929细胞 抗氧化
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Autism spectrum disorder:difficulties in diagnosis and microRNA biomarkers
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作者 Bridget Martinez Philip V.Peplow 《Neural Regeneration Research》 SCIE CAS 2025年第10期2776-2786,共11页
We performed a PubMed search for microRNAs in autism spectrum disorder that could serve as diagnostic biomarkers in patients and selected 17 articles published from January 2008 to December 2023,of which 4 studies wer... We performed a PubMed search for microRNAs in autism spectrum disorder that could serve as diagnostic biomarkers in patients and selected 17 articles published from January 2008 to December 2023,of which 4 studies were performed with whole blood,4 with blood plasma,5 with blood serum,1 with serum neural cell adhesion molecule L1-captured extracellular vesicles,1 with blood cells,and 2 with peripheral blood mononuclear cells.Most of the studies involved children and the study cohorts were largely males.Many of the studies had performed microRNA sequencing or quantitative polymerase chain reaction assays to measure microRNA expression.Only five studies had used real-time polymerase chain reaction assay to validate microRNA expression in autism spectrum disorder subjects compared to controls.The microRNAs that were validated in these studies may be considered as potential candidate biomarkers for autism spectrum disorder and include miR-500a-5p,-197-5p,-424-5p,-664a-3p,-365a-3p,-619-5p,-664a-3p,-3135a,-328-3p,and-500a-5p in blood plasma and miR-151a-3p,-181b-5p,-320a,-328,-433,-489,-572,-663a,-101-3p,-106b-5p,-19b-3p,-195-5p,and-130a-3p in blood serum of children,and miR-15b-5p and-6126 in whole blood of adults.Several important limitations were identified in the studies reviewed,and need to be taken into account in future studies.Further studies are warranted with children and adults having different levels of autism spectrum disorder severity and consideration should be given to using animal models of autism spectrum disorder to investigate the effects of suppressing or overexpressing specific microRNAs as a novel therapy. 展开更多
关键词 autism spectrum disorder BIOMARKER blood cells blood plasma blood serum DIAGNOSIS MICRORNA peripheral blood mononuclear cells serum neural cell adhesion molecule l1-captured extracellular vesicles whole blood
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Establishment on Isolated Microspore Culture Optimized System for Restorer of New Cytoplasmic Male Sterile (NER) of Brassica napus L.
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作者 李浩杰 蒲晓斌 +5 位作者 张锦芳 张德发 夏凊 石化娟 蒋俊 蒋梁材 《Agricultural Science & Technology》 CAS 2010年第1期182-185,共4页
[Objective]The aim was to establish optimized system for NER isolated microspore culture of Brassica napus L.. [Method]Twenty varieties of NER of Brassica napus were grown under uncontrolled temperature and light cond... [Objective]The aim was to establish optimized system for NER isolated microspore culture of Brassica napus L.. [Method]Twenty varieties of NER of Brassica napus were grown under uncontrolled temperature and light conditions,and their isolated microspore from anthers were used as explants in vitro culture. The influencing factors of microspore culture were preliminarily studied. [Result]The difference of genotypes was important influencing factors to embryoid yield. The embryoid yield increased by supplementing with 6-BA and NAA,culturing in solid-liquid double layer medium with activated charcoal; The difference was not significant of embryoid yield between culturing in medium supplemented with colchicines and the CK. The rates of cotyledonous embryoids directly developed into normal plantlets increased through enriching with 0.1-0.2 mg/L NAA and being treated on slim illumination two days before being inducted into normal plantlets. [Conclusion]The technical system of microspore culture of restorer of new cytoplasmic male sterile (NER) was established,which and lays a foundation for accelerating genotype purification of NER introgressive line. 展开更多
关键词 Brassica napus l. Restorer of new cytoplasmic male sterile (NER) Isolated microspore culture Technical system
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A Biosystematic Study on Asplenium sarelii Complex 被引量:5
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作者 王中仁 王可青 +1 位作者 张方 侯鑫 《Acta Botanica Sinica》 CSCD 2003年第1期1-14,共14页
The series Variantia Ching et S. H. Wu mainly occur in China and its members are highly variable in morphology. The denomination on this group of Asplenium is very confused in the herbaria. We hop e by means of a bios... The series Variantia Ching et S. H. Wu mainly occur in China and its members are highly variable in morphology. The denomination on this group of Asplenium is very confused in the herbaria. We hop e by means of a biosystematic study to find out their genetic relationships in the reticulate evolution, and to raise a suggestion on their taxonomic treatment. Evidence from cytology, allozyme, morphology, and palynology shows that three ancestor diploids have formed Asplenium sarelii complex comprising 13 members. A. sarelii Hook. should be typified as a diploid. The so-called tetraploid 'A. sarelii' before is an allotetraploid that comes from the doubled hybrid between diploid A. sarelii and A. tenuicaule Hayata, which should be treated as a new species A. wudangense Z. R. Wang et X. Hou. A. pekinense Hance is an autotetraploid that comes from the doubled diploid ancestor A. sarelii. A. lushanense C. Chr., a diploid species and the only ancestor of A. yunnariense group, should not been sunk as a synonym of tetraploid A. yunnariense Franch. Most probably, A. varians Wall. ex Hook. et Grev. is an autotetraploid of A. tenuicaule Hayata. Three new natural tetraploid hybrids and their origins have been found out: they are A. x longmenense ( = A. pekinense x varians), A. x jingyunense ( = A. pekinense x yunnanense) and A. x kidoi ( = A. pekinense x wudangense). Three other new natural triploid hybrids have been found and their origins have been inferred: they are A. X huawuense ( = A. sarelii X wudangense), A. x luyunense ( = A. lushanense x yunnanense) and A. x teniuvaians ( = A. tenuicaule x varians). The method of allozyme comparion combined with cytological observation is employed to reveal the complicated relationships among the members of Asplenium sarelii complex in reticulate evolution and proved to be a highly effective tool to investigate the origin of polyploid and hybrid. 展开更多
关键词 PTERIDOPHYTES Asplenium l. BIOsystemATICS reticulate evolution CYTOlOGY AllOZYME China
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Analysis of the Conditional Correlations from Different Genetic Systems Between the Protein Content and the Appearance Quality Traits of Indica Rice 被引量:4
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作者 葛国科 郑希 +2 位作者 吴建国 叶子弘 石春海 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第2期129-137,共9页
A factorial mating design in two environments was conducted using 7 cytoplasmic male sterile lines (A) and 5 restorer lines (R) along with their F1 (A × R) and F2 populations. The unconditional and conditio... A factorial mating design in two environments was conducted using 7 cytoplasmic male sterile lines (A) and 5 restorer lines (R) along with their F1 (A × R) and F2 populations. The unconditional and conditional analyses of genetic models and the corresponding statistic methods, including endospermic, cytoplasmic, and maternal plant genetic systems, were used to analyze the genetic relationships between protein content (PC) and the appearance quality traits of indica rice (Oryza sativa L.). The results from unconditional analysis indicated that PC was significantly correlated with the appearance quality traits of rice, except for the brown rice thickness (BRT). Only the genetic covariance between PC and the brown rice width (BRW) was positively correlative, whereas all the other pairwise traits were negatively correlative. The results from conditional analysis revealed that the weight of brown rice (WBR) or the amylose content (AC) could significantly affect the relationships between PC and the appearance quality traits of indica rice. The conditional analysis showed that WBR might negatively affect the relationships between PC and the brown rice length (BRL), BRW, or BRT through the geuotype x environmental (GE) interaction effects, but positively affected the relationships between PC and the ratio of brown rice length to width (RLW) or the ratio of brown rice length to thickness (RLT). The amylase content could positively affect the relationships between PC and BRL, RLW, RLT through the cytoplasmic effects and maternal additive effects, but negatively affected the relationships between PC and BRW. 展开更多
关键词 indica rice (Oryza sativa l.) COVARIANCE unconditional and conditional analysis methods protein content amylose content appearance quality
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Transcriptional Regulation of 10 Mitochondrial Genes in Different Tissues of NCa CMS System in Brassica napus L. and Their Relationship with Sterility 被引量:3
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作者 危文亮 王汉中 刘贵华 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第1期72-80,共9页
Northern blot analysis was conducted with mitochondrial RNA from seedling leaves, floral buds, and developing seeds of NCa CMS, maintainer line and fertile F1 using ten mitochondrial genes as probes. The results revea... Northern blot analysis was conducted with mitochondrial RNA from seedling leaves, floral buds, and developing seeds of NCa CMS, maintainer line and fertile F1 using ten mitochondrial genes as probes. The results revealed that 9 out of the 10 mitochondrial genes, except for atp6, showed no difference in different tissues of the corresponding materials of NCα CMS system and that they might be constitutively expressed genes. Eight genes, such as orf139, orf222, atpl, cox1, cox2, cob, rm5S, and rm26S, showed no difference among the three tissues of all the materials detected. So the expression of these eight genes was not regulated by nuclear genes and was not tissue-specific. The transcripts of atp9 were identical among different tissues, but diverse among different materials, indicating that transcription of atp9 was neither controlled by nuclear gene nor tissue-specific. Gene atp6 displayed similar transcripts with the same size among different tissues of all the materials but differed in abundance among tissues of corresponding materials and its expression might be tissue-specific under regulation of nuclear gene. Moreover, three transcripts of orf222 were detected in the floral buds of NCa cms and fertile F1, but no transcript was detected in floral buds of the maintainer line.The transcription of orf139 was similar to that of orf222 but only two transcripts of 0.8 kb and 0.6 kb were produced. The atp9 probe detected a single transcript of 0.6 kb in NCa cms and in maintainer line and an additional transcript of 1.2 kb in fertile F1. The relationship of expression of orf222, orf139, and atp9 with NCa sterility was discussed. 展开更多
关键词 Brassica napus l. cytoplasmic male sterility (CMS) mitochondrial gene expression restorer gene transcriptional regulation
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Establishment of High Frequency Regeneration System of Atropa belladonna L. and Screening of Kanamycin Resistance 被引量:2
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作者 王细荣 强玮 +2 位作者 卢衍 李金弟 廖志华 《Agricultural Science & Technology》 CAS 2011年第3期372-374,共3页
[Objective] The research aimed to establish the high frequency regeneration system of Atropa belladonna L. and screen the kanamycin (Kan) resistance. [Method] The leaves and axillary buds of Atropa belladonna L. wer... [Objective] The research aimed to establish the high frequency regeneration system of Atropa belladonna L. and screen the kanamycin (Kan) resistance. [Method] The leaves and axillary buds of Atropa belladonna L. were as the explants,the influences of different ratios of 6-BA and NAA in the medium on the adventitious bud differentiation and the sensibility of leaf on Kan were studied. [Result] MS+4.5 mg/L 6-BA+0.2 mg/L NAA was the optimum medium of leaf adventitious bud differentiation,and the differentiation ratio of adventitious bud reached 100%. The number of adventitious bud differentiation on 1. 0 cm ×1. 0 cm leaf block averagely reached 5.85. MS+3.0 mg/L 6-BA+0.1 mg/L NAA was the optimum medium of axillary bud adventitious bud differentiation,and the differentiation ratio of adventitious bud reached 100%. The average number of adventitious bud differentiation in every axillary bud was during 4-8. The optimum screening concentration for genetic transformation of Atropa belladonna L. leaf was 400.0 mg/L of Kan. [Conclusion] The research laid the foundation for the rapid propagation of Atropa belladonna L. aseptic seedling and the genetic transformation based on the leaf disc cocultivation. 展开更多
关键词 Atropa belladonna l. Regeneration system Kan SENSIBIlITY
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用L-systems和遗传算法实现的叶子形状建模 被引量:5
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作者 吕慧强 李益明 孔繁胜 《计算机工程》 CAS CSCD 北大核心 2004年第11期132-134,共3页
阐述了组合两类技术的一种方法:用L-systems和遗传算法(GA)获取一种改写表达式描述叶子形状。一个L-systems用于构造给定改写表达式,而GA是用于改写表达式的适应参数。介绍了用目标函数实现实值参数替换方法,研究结果表明提出的方法产... 阐述了组合两类技术的一种方法:用L-systems和遗传算法(GA)获取一种改写表达式描述叶子形状。一个L-systems用于构造给定改写表达式,而GA是用于改写表达式的适应参数。介绍了用目标函数实现实值参数替换方法,研究结果表明提出的方法产生可以接受的输 出效果。 展开更多
关键词 l-systemS 遗传算法(GA) 叶子 建模
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基于Open L—System的植物生长模拟研究 被引量:1
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作者 姜明明 赵晓春 唐特 《中国农学通报》 CSCD 北大核心 2009年第16期284-287,共4页
简述了OpenL-系统的基本原理,并基于OpenL-系统对草本植物的形态进行了模拟。在模拟过程中,对植物的分枝结构,叶片的分别,生长方向进行控制,并根据植物生长过程中其形态特征与环境信息之间的动态交互过程,构建了环境模型,实现了植物与... 简述了OpenL-系统的基本原理,并基于OpenL-系统对草本植物的形态进行了模拟。在模拟过程中,对植物的分枝结构,叶片的分别,生长方向进行控制,并根据植物生长过程中其形态特征与环境信息之间的动态交互过程,构建了环境模型,实现了植物与环境并发过程的模拟研究并模拟了部分环境因素对植物生长过程形态结构的影响。 展开更多
关键词 虚拟植物 OPEN lsystem 植物模型 环境交互模型
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Phase equilibria in Co-rich region of Co-Ti-Ta system 被引量:1
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作者 蒋敏 萨仁格日乐 +2 位作者 杨舒宇 李洪晓 郝士明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第11期2391-2395,共5页
The phase equilibria in Co-rich region of Co-Ti-Ta system were studied.The microstructure and XRD analysis together with EDS determination show that L12 type Co3Ti phase and Laves_C36_Co3Ta phase get equilibrium with ... The phase equilibria in Co-rich region of Co-Ti-Ta system were studied.The microstructure and XRD analysis together with EDS determination show that L12 type Co3Ti phase and Laves_C36_Co3Ta phase get equilibrium with α-Co phase from 1 000 to 1 200 ℃.The Co3Ti phase possesses a solubility of Ta higher than 10%,and the addition of Ta stabilizes the Co3Ti phase.The isothermal sections of the Co-Ti-Ta system in the Co-rich region at 1 000,1 100 and 1 200 ℃ were constructed according to the result. 展开更多
关键词 l12 type intermetallic compound phase equilibrium Co-Ti-Ta Co-based superalloys
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