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Nielsen Theory on 3-manifolds Covered by S^2× R

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Acta Mathematica Sinica,English Series 2015年第4期31卷 615-636页

作者： Daciberg GONALVES Peter WONG xue zhi zhao Dept. de Matemtica-IME-USP Caixa Postal 66.281-CEP 05314-970So Paulo-SP Brasil Department of Mathematics Bates College Department of Mathematics & Institute of Mathematics and Interdisciplinary Science Capital Normal University

Let f ： M→ M be a self-map of a closed manifold M of dimension dim M ≥ 3. The Nielsen number N（f） of f is equal to the minimal number of fixed points of f＇ among all self-maps f＇ in the homotopy class of f. In this paper, we determine N（f） for all self-maps f when M is a closed 3-manifold with S^2× R geometry. The calculation of N（f） relies on the induced homomorphisms of f on the fundamental group and on the second homotopy group of M.

关键词： Lefschetz number Nielsen number 3-manifolds

Errata to “On Self-mapping Degrees of S^3-geometry Manifolds”

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Acta Mathematica Sinica,English Series 2019年第12期35卷 1979-1982页

作者： Xiao Ming DU xue zhi zhao School of Mathematics South China University of TechnologyGangzhou 510640P.R.China Department of Mathematics Capital Normal UniversityBeijing 100048P.R.China

The set of self-mapping degrees of S^3-geometry 3-manifolds in[2]have some mistakes when the fundamental group of the 3-manifold is D4n^*,O48^*,D'n·2q or T'8·*** we need to make this *** self-mapping degrees of all closed and oriented 3-manifolds are listed in[1]and[5].The table of spherical case in[5]is mostly quoted from[2].The results in[5]which do not involve the corrections made here still *** results in[5]involving the corrections made here should be also changed.

关键词： Mapping degree spherical manifold

New insights into the mechanism of surfactant enhanced oil recovery:Micellar solubilization and in-situ emulsification

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Petroleum Science 2022年第2期19卷 870-881页

作者： xue-zhi zhao Guang-zhi Liao Ling-Yan Gong Huo-Xin Luan Quan-Sheng Chen Wei-Dong Liu Dong Liu Yu-Jun Feng Polymer Research Institute State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065People's Republic of China PetroChina Exploration&Production Company Beijing100007People's Republic of China Research Institute of Experiment and Detection Xinjiang Oilfield Branch CompanyPetroChinaKaramay834000People's Republic of China Research Institute of Petroleum Exploration&Development PetroChina Company LimitedBeijing100083People's Republic of China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang621000People's Republic of China

Reducing the oil-water interfacial tension(IFT)to ultra-low is believed the primary mechanism for surfactant-based enhanced oil recovery(EOR)***,field trials have shown that low concentration surfactant flooding can also improve oil recovery without ultra-low *** clarify the mechanism behind,the currently-used surfactant,naphthenic arylsulfonate(NAS),was used to unravel its function during surfactant flooding from the horizon of micron-and *** solubilization capacity of NAS micelle to petroleum fractions was evaluated through light absorbance strategy,smallangle neutron scattering,dynamic light scattering and transmission electron *** was found that micellar solubilization plays a significant role during the surfactant ***-situ emulsification was visualized in microfluidics with three types of microchips,respectively.A series of displacement tests were carried out with NAS solution pumping into oil-saturated *** results show that in-situ emulsification improve oil recovery mainly through blocking and entrainment *** from this work aid in understanding the interaction between surfactant solution and petroleum fractions at low surfactant concentration,which is helpful for design surfactant-based displacing system for EOR process.

关键词： Enhanced oil recovery Surfactant flooding Micellar solubilization Microfluidics In-situ emulsification

Visualization of adaptive polymer flow and displacement in medium-permeable 3D core-on-a-chip

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Petroleum Science 2023年第2期20卷 1018-1029页

作者： Yan Zhang xue-zhi zhao Pei-Hui Han Li-Yuan Zhang David A.Weitz Yu-Jun Feng Polymer Research Institute State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065SichuanPR China EOR Laboratory Exploration&Development Research InstituteDaqing Oilfield Limited CompanyPetroChinaDaqing163712HeilongjiangPR China School of Engineering and Applied Sciences Harvard UniversityCambridge02138United States School of Petroleum Engineering China University of PetroleumQingdao266580ShandongPR China

Polymer flooding has been witnessed an effective technology for enhancing oil recovery from medium-to low-permeability reservoirs;however, direct visualization of polymer solution flow in such reservoir condition is still lacking. In this work, a three-dimensional (3D) core-on-a-chip device with a permeability of around 200 mD was prepared and employed to visualize the pore-scale flow and displacement of a self-adaptive polymer (SAP, 8.7 × 106 g·mol−1)−whose microscopic association structure and macroscopic viscosity can reversibly change in response to shear action−versus partially hydrolyzed polyacrylamide (HPAM), by recording their flow curves, monitoring dynamic transportation process via particle imaging velocimetry, and building 3D structure of remaining oil. The results show that, in single-phase flow, all polymer solutions exhibit flow thinning and then thickening regions as flow rate increases, but the transition between two regimes occurs at a small Weissenberg number (10−3−10−1) in this medium-permeable condition. In contrast to HPAM-1 with close weight-average molecular weight (Mw), the adaptive character not only extends SAP's shear-govern region, allowing SAP to propagate piece by piece and achieve higher accessible pore volume, but it also enhances the elastic resistibility of polymer in the extension-dominated regime, increasing the microscopic displacement efficiency. These two effects result in 1.5–3 times more oil recovery factor for SAP than for HPAM-1. Regarding ultra-high-Mw HPAM-2 (25 × 106 g·mol−1), plugging and chain degradation do occur, thus producing lower oil recovery than SAP. This work provides a direct approach for in-situ assessment of polymer-based displacing system under a more authentic condition of practical reservoirs.

关键词： Polymer flooding Medium-permeable transparent media Adaptive polymer In-situ rheology Particle imaging velocimetry

ANNEXIN 8 negatively regulates RPW8.1-mediated cell death and disease resistance in Arabidopsis

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Journal of Integrative Plant Biology 2021年第2期63卷 378-392页

作者： zhi-xue zhao Yong-Ju Xu Yang Lei Qin Li Ji-Qun zhao Yan Li Jing Fan Shunyuan Xiao Wen-Ming Wang Rice Research Institute and Key Laboratory for Major Crop Diseases Sichuan Agricultural UniversityChengdu 611130China Institute for Bioscience and Biotechnology Research&Department of Plant Science and Landscape Architecture University of MarylandRockvilleMaryland 20850USA

Study on the regulation of broad-spectrum resistance is an active area in plant biology. RESISTANCE TO POWDERY MILDEW 8.1(RPW8.1)is one of a few broad-spectrum resistance genes triggering the hypersensitive response(HR) to restrict multiple pathogenic infections. To address the question how RPW8.1 signaling is regulated,we performed a genetic screen and tried to identify mutations enhancing RPW8.1-mediated ***, we provided evidence to connect an annexin protein with RPW8.1-mediated resistance in Arabidopsis against powdery mildew. We isolated and characterized Arabidopsis b7-6 mutant.A point mutation in b7-6 at the At5 g12380 locus resulted in an amino acid substitution in ANNEXIN8(AtANN8). Loss-of-function or RNA-silencing of AtANN8 led to enhanced expression of RPW8.1,RPW8.1-dependent necrotic lesions in leaves, and defense against powdery mildew. Conversely,over-expression of AtANN8 compromised RPW8.1-mediated disease resistance and cell death. Interestingly, the mutation in AtANN8 enhanced RPW8.1-triggered H2O2. In addition, mutation in AtANN8 led to hypersensitivity to salt stress. Together, our data indicate that AtANN8 is involved in multiple stress signaling pathways and negatively regulates RPW8.1-mediated resistance against powdery mildew and cell death, thus linking ANNEXIN’s function with plant immunity.

关键词： AtANN8 cell death disease resistance H2O2 hypersensitive response powdery mildew RPW8.1

Osa-miR167d facilitates infection of Magnaporthe oryzae in rice

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Journal of Integrative Plant Biology 2020年第5期62卷 702-715页

作者： zhi-xue zhao Qin Feng Xiao-Long Cao Yong Zhu He Wang Viswanathan Chandran Jing Fan Ji-Qun zhao Mei Pu Yan Li Wen-Ming Wang Rice Research Institute and Key Lab for Major Crop Diseases Sichuan Agricultural UniversityChengdu 611130China Department of Biotechnology Sree Narayana Guru CollegeCoimbatoreTamilnaduIndia

MicroRNAs(miRNAs)play important roles in rice response to Magnaporthe oryzae,the causative agent of rice blast *** the roles of rice miRNAs is of great significance for the disease ***-miR167d belongs to a conserved miRNA family targeting auxin responsive factor(ARF)genes that act in developmental and stress-induced ***,we show that OsamiR167d plays a negative role in rice immunity against *** by suppressing its target *** expression of Osa-miR167d was significantly suppressed in a resistant accession at and after 24 h post inoculation(hpi),however,its expression was significantly increased at 24 hpi in the susceptible accession upon *** *** rice lines over-expressing Osa-miR167d were highly susceptible to multiple blast fungal *** contrast,transgenic lines expressing a target mimicry to block OsamiR167d enhanced resistance to rice blast *** addition,knocking out the target gene ARF12 led to hypersusceptibility to multiple blast fungal *** together,our results indicate that Osa-miR167d negatively regulate rice immunity to facilitate the infection of *** by downregulating ***,Osa-miR167d-ARF12 regulatory module could be valuable in improvement of blast-disease resistance.

关键词： immunity expressing infection

Synthesis of Nanometer-sized Mesoporous Oxide Spheres

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Chemical Research in Chinese Universities 2001年第2期17卷 143-147页

作者： LUO Qian, LI Li, xue zhi-yuan and zhao Dong-yuan (Department of Chemistry Analysis and Measurement Center, Fudan University, Shanghai 200433, P. R. China) 复旦大学上海 200433

A few hundreds nanometer-sized mesoporous silica and alumina spheres were synthesized in organic solvents. The impacts of ammonia, N, N-dimethylformamide (DMF) and stirring speed were also investigated.

关键词： Nanometer-sized Mesoporous Sphere Silica Alumina

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后掠翼边界层定常横流涡的非线性演化

应用数学和力学 2016年第10期37卷 1073-1084页

作者：逯学志赵磊罗纪生天津大学力学系天津300072

横流失稳是后掠翼边界层主要的失稳形式.实验和数值研究发现在后掠翼边界层转捩之前,有一段较长的非线性幅值饱和阶段,因此线性稳定性不能有效预测横流失稳转捩过程,所以研究横流涡的非线性演化过程就极为必要.以NLF(2)-0415翼型为研究... 详细信息

横流失稳是后掠翼边界层主要的失稳形式.实验和数值研究发现在后掠翼边界层转捩之前,有一段较长的非线性幅值饱和阶段,因此线性稳定性不能有效预测横流失稳转捩过程,所以研究横流涡的非线性演化过程就极为必要.以NLF(2)-0415翼型为研究模型,在来流Mach数为0.8、后掠角为45°、攻角为-4°的条件下,用扰动方程计算了定常横流涡非线性演化过程.结果显示非平行性起着更加不稳定的作用.当基本波的幅值到达0.1时,非线性作用开始明显.横流涡经历了非线性幅值饱和过程,涡的形状呈现半蘑菇状,涡的涡轴与边界层外缘无粘势流平行.饱和涡使得原有流场发生极大的扭曲,流向速度和展向剖面出现了拐点.

关键词：后掠翼定常横流涡非平行性幅值饱和非线性演化

Overproduction of OsRACK1A,an effector-targeted scaffold protein promoting OsRBOHB-mediated ROS production,confers rice floral resistance to false smut disease without yield penalty

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Molecular Plant 2022年第11期15卷 1790-1806页

作者： Guo-Bang Li Jia-xue He Jin-Long Wu He Wang Xin Zhang Jie Liu Xiao-Hong Hu Yong Zhu Shuai Shen Yi-Fei Bai Zong-Lin Yao Xin-Xian Liu Jing-Hao zhao De-Qiang Li Yan Li Fu Huang Yan-Yan Huang zhi-xue zhao Ji-Wei Zhang Shi-Xin Zhou Yun-Peng Ji Mei Pu Peng Qin Shigui Li xuewei Chen Jing Wang Min He Weitao Li Xian-Jun Wu Zheng-Jun Xu Wen-Ming Wang Jing Fan State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China Sichuan Agricultural UniversityChengdu 611130China Rice Research Institute Sichuan Agricultural UniversityChengdu 611130China

Grain formation is fundamental for crop yield but is vulnerable to abiotic and biotic *** grain production is threatened by the false smut fungus Ustilaginoidea virens,which specifically infects rice floral organs,disrupting fertilization and seed ***,little is known about the molecular mechanisms of the ***-rice interaction and the genetic basis of floral ***,we report that *** secretes a cytoplasmic effector,UvCBP1,to facilitate infection of rice ***,UvCBP1 interacts with the rice scaffold protein OsRACK1A and competes its interaction with the reduced nicotinamide adenine dinucleotide phosphate oxidase OsRBOHB,leading to inhibition of reactive oxygen species(ROS)*** the analysis of natural variation revealed no OsRACK1A variants that could avoid being targeted by UvCBP1,expression levels of OsRACK1A are correlated with field resistance against *** in rice *** of OsRACK1A restores the OsRACK1A-OsRBOHB association and promotes OsRBOHB phosphorylation to enhance ROS production,conferring rice floral resistance to *** without yield *** together,our findings reveal a new pathogenic mechanism mediated by an essential effector from a flower-specific pathogen and provide a valuable genetic resource for balancing disease resistance and crop yield.

关键词： rice flower false smut fungal effector scaffold protein reactive oxygen species disease resistance