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Lipschitz Shadowing Property for 1-Dimensional Subsystems of Z^(k)-Actions 被引量:5
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作者 Lin WANG Jinlian ZHANG 《Journal of Mathematical Research with Applications》 CSCD 2021年第6期615-628,共14页
In this paper,the shadowing property for 1-dimensional subsystems of Z^(k)-actions is investigated.The concepts of pseudo orbit and shadowing property for 1-dimensional subsystems of Z^(k)-actions are introduced in tw... In this paper,the shadowing property for 1-dimensional subsystems of Z^(k)-actions is investigated.The concepts of pseudo orbit and shadowing property for 1-dimensional subsystems of Z^(k)-actions are introduced in two equivalent ways.For a smooth Z^(k)-action T on a closed Riemannian manifold,we propose a notion of Anosov direction via the induced nonautonomous dynamical system.Adapting Bowen’s geometric method to our case,we show that T has the Lipschitz shadowing property along any Anosov direction. 展开更多
关键词 Z^(k)-actions Lipschitz shadowing 1-dimensional subsystem
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Dynamic Behaviors of Localized Waves of the(2+1)-Dimensional Yu-Toda-Sasa-Fukuyama Equation
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作者 SUN Xiaoqing XIA Yarong +1 位作者 YAO Ruoxia WANG Weiqing 《应用数学》 北大核心 2026年第2期624-638,共15页
In this article,by employing the Hirota bilinear approach and the long wave limit method,we not only derive soliton solutions,lump solutions,and hybrid solutions for the(2+1)-dimensional Yu-Toda-Sasa-Fukuyama(YTSF)equ... In this article,by employing the Hirota bilinear approach and the long wave limit method,we not only derive soliton solutions,lump solutions,and hybrid solutions for the(2+1)-dimensional Yu-Toda-Sasa-Fukuyama(YTSF)equation,but also analyze the dynamical behaviors of nonlinear local wave propagation in shallow water.Firstly,based on the Hirota bilinear approach,one to four-order soliton solutions of the YTSF equation are obtained,and the effects of different parameters on the amplitude,propagation trajectory,and displacement of solitons are investigated.Secondly,using the long wave limit approach,one to three-order lump solutions and various physical quantities of the YTSF equation are derived.It is found that the real and imaginary parts of the parameter pi dominate the propagation trajectory and the shape of lump waves,respectively.Furthermore,we construct the hybrid solution for the YTSF equation,leading to the conclusion that the interaction between lumps and solitons constitutes an elastic collision.To intuitively understand the dynamic behaviors of these solutions,we conduct numerical simulations to present vivid three-dimensional visualizations. 展开更多
关键词 (2+1)-dimensional Yu-Toda-Sasa-Fukuyama equation Hirota bilinear approach Lump solutions Dynamic behaviors
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Recent progress in studies of cobalt-based quasi-1-dimensional quantum magnets
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作者 Lun Jin Robert J.Cava 《Frontiers of physics》 2025年第3期101-116,共16页
The interplay of crystal electric field,temperature,and spin–orbit coupling can yield a Kramer ion and thus an effective S=1/2 ground state for Co^(2+)ions(3d^(7)),which is often the case for low-dimensional material... The interplay of crystal electric field,temperature,and spin–orbit coupling can yield a Kramer ion and thus an effective S=1/2 ground state for Co^(2+)ions(3d^(7)),which is often the case for low-dimensional materials.This is because a highly anisotropic structural motif can force the spins to point either“up”or“down,”thereby creating a system where spins communicate via Ising interactions.Cobalt-based quasi-1-dimensional materials have been studied in this context since the latter half of the 20th century.However,due to the development of modern characterization techniques and advances in sample preparation,the exotic physical phenomena that have generated the most interest have only emerged in the past three to four decades.This topical review mainly summarizes progress in cobalt-based quasi-1-dimensional quantum magnets and comments on a few research directions of potential future interest. 展开更多
关键词 quasi-1-dimensional materials quantum magnet Co^(2+)ion Ising interaction quantum phase transition fieldinduced magnetic transition magnetic frustration quantum fluctuations
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In an Ocean or a River:Bilinear Auto-Backlund Transformations and Similarity Reductions on an Extended Time-Dependent(3+1)-Dimensional Shallow Water Wave Equation 被引量:2
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作者 GAO Xin-yi 《China Ocean Engineering》 2025年第1期160-165,共6页
With respect to oceanic fluid dynamics,certain models have appeared,e.g.,an extended time-dependent(3+1)-dimensional shallow water wave equation in an ocean or a river,which we investigate in this paper.Using symbolic... With respect to oceanic fluid dynamics,certain models have appeared,e.g.,an extended time-dependent(3+1)-dimensional shallow water wave equation in an ocean or a river,which we investigate in this paper.Using symbolic computation,we find out,on one hand,a set of bilinear auto-Backlund transformations,which could connect certain solutions of that equation with other solutions of that equation itself,and on the other hand,a set of similarity reductions,which could go from that equation to a known ordinary differential equation.The results in this paper depend on all the oceanic variable coefficients in that equation. 展开更多
关键词 OCEAN RIVER extended time-dependent(3+1)-dimensional shallow water wave equation bilinear auto-Bäcklund transformation similarity reduction symbolic computation
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Open-Ocean Shallow-Water Dynamics via a(2+1)-Dimensional Generalized Variable-Coefficient Hirota-Satsuma-Ito System: Oceanic Auto-B?cklund Transformation and Oceanic Solitons
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作者 GAO Xin-yi 《China Ocean Engineering》 2025年第3期541-547,共7页
Recently, during the investigations on planetary oceans, Hirota-Satsuma-Ito-type models have been developed. In this paper, for a(2+1)-dimensional generalized variable-coefficient Hirota-Satsuma-Ito system describing ... Recently, during the investigations on planetary oceans, Hirota-Satsuma-Ito-type models have been developed. In this paper, for a(2+1)-dimensional generalized variable-coefficient Hirota-Satsuma-Ito system describing the fluid dynamics of shallow-water waves in an open ocean, non-characteristic movable singular manifold and symbolic computation enable an oceanic auto-B?cklund transformation with three sets of the oceanic solitonic solutions. The results rely on the oceanic variable coefficients in that system. Future oceanic observations might detect some nonlinear features predicted in this paper, and relevant oceanographic insights might be expected. 展开更多
关键词 OCEAN shallow water (2+1)-dimensional generalized variable-coefficient Hirota-Satsuma-Ito system singular manifold symbolic computation B?cklund transformation soliton
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NONLINEAR WAVE TRANSITIONS AND THEIR MECHANISMS OF THE(2+1)-DIMENSIONAL KORTEWEG-DE VRIES-SAWADA-KOTERA-RAMANI EQUATION
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作者 Haolin WANG Shoufu TIAN Tiantian ZHANG 《Acta Mathematica Scientia》 2025年第4期1405-1437,共33页
In this work,we study wave state transitions of the(2+1)-dimensional Kortewegde Vries-Sawada-Kotera-Ramani(2KdVSKR)equation by analyzing the characteristic line and phase shift.By converting the wave parameters of the... In this work,we study wave state transitions of the(2+1)-dimensional Kortewegde Vries-Sawada-Kotera-Ramani(2KdVSKR)equation by analyzing the characteristic line and phase shift.By converting the wave parameters of the N-soliton solution into complex numbers,the breath wave solution is constructed.The lump wave solution is derived through the long wave limit method.Then,by choosing appropriate parameter values,we acquire a number of transformed nonlinear waves whose gradient relation is discussed according to the ratio of the wave parameters.Furthermore,we reveal transition mechanisms of the waves by exploring the nonlinear superposition of the solitary and periodic wave components.Subsequently,locality,oscillation properties and evolutionary phenomenon of the transformed waves are presented.And we also prove the change in the geometrical properties of the characteristic lines leads to the phenomena of wave evolution.Finally,for higher-order waves,a range of interaction models are depicted along with their evolutionary phenomena.And we demonstrate that their diversity is due to the fact that the solitary and periodic wave components produce different phase shifts caused by time evolution and collisions. 展开更多
关键词 the(2+1)-dimensional Korteweg-de Vries-Sawada-Kotera-Ramani equation characteristic line transformed nonlinear waves phase shift collision
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Lax integrability and superposition wave solutions of(3+1)-dimensional generalized Calogero–Bogoyavlenskii–Schiff equation
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作者 Taogetusang Bao Xiaole Zhang 《Communications in Theoretical Physics》 2025年第10期71-84,共14页
In this article,a Generalized Calogero-Bogoyavlenskii-Schiff(CBS)equation is studied,serving as an extended shallow water wave model in higher dimensions.Firstly,utilizing the Bell polynomial method,the bilinear form ... In this article,a Generalized Calogero-Bogoyavlenskii-Schiff(CBS)equation is studied,serving as an extended shallow water wave model in higher dimensions.Firstly,utilizing the Bell polynomial method,the bilinear form of the equation,bilinear Bäcklund transformation,Lax pair and infinite conservation laws are derived,confirming the equation’s complete integrability in the context of the Lax pair.Subsequently,the nonlinear superposition formula of the equation is constructed based on the derived bilinear Bäcklund transformation and an array of infinite superposition soliton solutions of the equation are formulated using this nonlinear superposition formula.Lastly,leveraging the obtained bilinear equation,infinite superposition solutions of various functional types are constructed.Their dynamic characteristics are analyzed through illustrated solution images.It is noteworthy that this paper not only uncovers a multitude of properties through the Bell polynomial method but also derives both infinite linear and nonlinear superposition solutions,enriching the diversity of solutions,these aspects have not been previously explored in existing literature. 展开更多
关键词 Bell-polynomial method Lax integrability nonlinear superposition formula infinite superposition solutions (3+1)-dimensional generalized CBS equation
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New types of nondegenerate solitons for a(2+1)-dimensional coupled system
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作者 Yong Meng Hafiz Wajahat Ahmed Riaz Ji Lin 《Communications in Theoretical Physics》 2025年第9期1-9,共9页
In this paper,we investigate the(2+1)-dimensional three-component long-wave-short-wave resonance interaction system,which describes complex systems and nonlinear wave phenomena in physics.By employing the Hirota bilin... In this paper,we investigate the(2+1)-dimensional three-component long-wave-short-wave resonance interaction system,which describes complex systems and nonlinear wave phenomena in physics.By employing the Hirota bilinear method,we derive the general nondegenerate N-soliton solution of the system,where each short-wave component contains N arbitrary functions of the independent variable y.The presence of these arbitrary functions in the analytical solution enables the construction of a wide range of nondegenerate soliton types.Finally,we illustrate the structural features of several novel nondegenerate solitons,including M-shaped,multiple double-hump,and sawtooth double-striped solitons,as well as interactions between nondegenerate solitons,such as dromion-like solitons and solitoffs,with the aid of figures. 展开更多
关键词 (2+1)-dimensional coupled system general nondegenerate N-soliton solution arbitrary functions modulation waveform
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Abundant invariant solutions of(3+1)-dimensional combined pKP-BKP equation
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作者 Hengchun Hu Xu Xu 《Chinese Physics B》 2025年第3期291-299,共9页
Lie symmetry analysis is applied to a(3+1)-dimensional combined potential Kadomtsev-Petviashvili equation with B-type Kadomtsev-Petviashvili equation(pKP-BKP equation)and the corresponding similarity reduction equatio... Lie symmetry analysis is applied to a(3+1)-dimensional combined potential Kadomtsev-Petviashvili equation with B-type Kadomtsev-Petviashvili equation(pKP-BKP equation)and the corresponding similarity reduction equations are obtained with the different infinitesimal generators.Invariant solutions with arbitrary functions and constants for the(3+1)-dimensional pKP-BKP equation,including the lump solution,the periodic-lump solution,the two-kink solution,the breather solution and the lump-two-kink solution,have been studied analytically and graphically. 展开更多
关键词 (3+1)-dimensional combined pKP-BKP equation Lie symmetry invariant solutions
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Controllable growth of wafer-scale two-dimensional PdS_(2x)Se_(2(1-x))nanofilms with fully tunable compositions for high-performance photodetectors
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作者 Huan Zhou Yulong Hao +10 位作者 Chen Fan Shiwei Zhang Chen Wang Kaiyi Wang Jie Zhou Shijie Hao Ting Shu Xuemei Lu Bo Li Yongqiang Yu Guolin Hao 《Journal of Materials Science & Technology》 2025年第25期200-207,共8页
Two-dimensional(2D)noble transition-metal dichalcogenide materials(NTMDs)have garnered remarkable attention due to their intriguing properties exhibiting potential applications in nanoelectronics,optoelectronics,and p... Two-dimensional(2D)noble transition-metal dichalcogenide materials(NTMDs)have garnered remarkable attention due to their intriguing properties exhibiting potential applications in nanoelectronics,optoelectronics,and photonics.The electronic structure and physical properties of 2D NTMDs can be effectively modulated using alloy engineering strategy.Nevertheless,the precise growth of wafer-scale 2D NTMDs alloys remains a significant challenge.In this work,we have achieved the controllable preparation of wafer-scale(2-inch)2D PdS_(2x)Se_(2(1-x)) nanofilms(NFs)with fully tunable compositions on various substrates using pre-deposited Pd NFs assisted chemical vapor deposition technique.High-performance photodetectors based on the PdS_(2x)Se_(2(1-x))NFs were fabricated,which exhibit broadband photodetection performance from visible to near-infrared(NIR)wavelength range at room temperature.Significantly,the PdS0.9Se1.1-based photodetectors display a responsivity up to 0.192 A W^(-1) and a large specific detectivity of 5.5×1011 Jones for 850 nm light,enabling an excellent high-resolution NIR single-pixel imaging(SPI)without an additional filtering circuit.Our work paves a new route for the controlled synthesis of wafer-scale and high-quality 2D NTMDs alloy NFs,which is essential for designing advanced optoelectronic devices. 展开更多
关键词 PdS_(2x)Se_(2(1-x)) NANOFILMS Wafer-scale Controllable growth PHOTODETECTORS Single-pixel imaging
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南瓜新品种龙贝1号的选育
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作者 赵丹 温玲 +6 位作者 王远纤 王喜庆 李柱刚 王珣 许春梅 李岩 杨帆 《中国瓜菜》 北大核心 2026年第1期229-232,共4页
龙贝1号是以H2017-41-1为母本、H2017-40-3为父本配置而成的杂交1代贝贝型南瓜新品种。该品种早熟,在黑龙江省春季棚室栽培果实发育期29 d左右,全生育期87 d。植株长势健壮,分枝性强,叶片浓绿,坐果性突出。果实扁圆形,外观靓丽,商品性佳... 龙贝1号是以H2017-41-1为母本、H2017-40-3为父本配置而成的杂交1代贝贝型南瓜新品种。该品种早熟,在黑龙江省春季棚室栽培果实发育期29 d左右,全生育期87 d。植株长势健壮,分枝性强,叶片浓绿,坐果性突出。果实扁圆形,外观靓丽,商品性佳;果皮黑绿色,果线细长、浅绿色,果肉黄色,平均果肉厚度1.8 cm,品质佳,软糯香甜,平均干物质含量(w)21%,总糖含量8.34%,可溶性固形物含量10.7%。单果质量0.6 kg左右,连续坐果能力强,中抗病毒病。棚室栽培667 m^(2)产量1887 kg左右,耐贮运性好。该品种适应性强,适于全国各地保护地栽培。 展开更多
关键词 南瓜 新品种 龙贝1 杂交1
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油棕中果皮酵母单杂交文库构建及EgWRI1-1上游调控因子筛选
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作者 周丽霞 曹红星 +5 位作者 李睿 吴秋妃 李启黉 付登强 刘小玉 杨耀东 《分子植物育种》 北大核心 2026年第3期740-745,共6页
EgWRI1-1在油棕中果皮(非种子组织)脂肪酸合成与积累过程中起着关键的调控作用,为了筛选EgWRI1-1的上游调控因子,本研究构建油棕中果皮核系统酵母单杂交文库,并利用该文库对与EgWRI1-1互作的蛋白进行筛选。检测结果表明该文库的库容是1.... EgWRI1-1在油棕中果皮(非种子组织)脂肪酸合成与积累过程中起着关键的调控作用,为了筛选EgWRI1-1的上游调控因子,本研究构建油棕中果皮核系统酵母单杂交文库,并利用该文库对与EgWRI1-1互作的蛋白进行筛选。检测结果表明该文库的库容是1.15×10^(7)CFU,平均插入片段大于1200 bp,阳性率为100%。转录自激活发现100 mmol/L 3-AT即可抑制诱饵载体的转录自激活,并利用酵母单杂交技术筛选获得与EgWRI1-1启动子互作的蛋白EgNF-YA3。本试验构建了油棕中果皮酵母单杂交文库,并获得与EgWRI1-1上游启动子互作的EgNF-YA3蛋白,该结果为深入解析EgWRI1-1在油棕中果皮脂肪酸合成积累过程中的调控机理提供参考。 展开更多
关键词 油棕 WRI1-1基因 酵母单杂交文库 上游调控因子
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LC3介导的细胞自噬通过靶向SIRT1促进糖尿病胃轻瘫发生
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作者 李萍 张添妮 +1 位作者 胡剑卓 王燚霈 《中南大学学报(医学版)》 北大核心 2026年第1期84-96,共13页
目的:糖尿病胃轻瘫(diabetic gastroparesis,DGP)是糖尿病的常见并发症,其发病机制复杂,尚未被完全阐明。本研究旨在探讨微管相关蛋白1轻链3(microtubule-associated protein 1 light chain 3,LC3)介导的细胞自噬是否通过靶向去乙酰化酶... 目的:糖尿病胃轻瘫(diabetic gastroparesis,DGP)是糖尿病的常见并发症,其发病机制复杂,尚未被完全阐明。本研究旨在探讨微管相关蛋白1轻链3(microtubule-associated protein 1 light chain 3,LC3)介导的细胞自噬是否通过靶向去乙酰化酶1(sirtuin 1,SIRT1)促进DGP进展。方法:采用35 mmol/L葡萄糖处理大鼠胃平滑肌细胞(gastric smooth muscle cells,GSMCs)以建立DGP模型,采用3-甲基腺嘌呤(3-methyladenine,3-MA)抑制自噬。检测细胞凋亡率、锥虫蓝阳性细胞率、细胞存活率、SIRT1、自噬标志物(LC3 II、LC3 I、Beclin-1、p62)、凋亡相关蛋白[B细胞淋巴瘤-2(B-cell lymphoma-2, Bcl-2)、 Bcl-2相关X蛋白(Bcl-2-associated X protein, Bax)、 cleaved及noncleaved caspase-3]的变化,通过免疫共沉淀验证LC3 II与SIRT1的相互作用。将6~8周龄SD大鼠随机分为正常组、阴性对照组、模型组及模型+3-MA组,每组6只,检测胃内色素残留率、肠道推进率、SIRT1及凋亡相关蛋白水平,采用原位末端转移酶标记法(terminal-deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling,TUNEL)染色检测胃组织中细胞凋亡水平。结果:高糖导致GSMCs凋亡率和锥虫蓝阳性细胞率升高,存活率降低;同时高糖也引起SIRT1、Bcl-2、p62水平均下调,LC3 II/LC3 I比值、Beclin-1、Bax及cleaved caspase-3水平均上调(均P<0.05);3-MA可逆转高糖对GSMCs的影响。在高糖处理且3-MA干预的GSMCs中,沉默SIRT1引起细胞凋亡率及锥虫蓝阳性细胞率升高,存活率降低;LC3 II/I比值、Beclin-1、Bax及cleaved caspase-3水平均显著升高,而SIRT1、Bcl-2、p62水平均显著降低(均P<0.05)。此外,高糖导致细胞核SIRT1水平降低(P<0.05),并引起细胞质SIRT1上调(P<0.05),3-MA处理可逆转高糖对细胞核及细胞质SIRT1的影响。免疫共沉淀结果表明SIRT1可与LC3相互作用;干扰LC3-SIRT1相互作用引起细胞核SIRT1水平升高,并下调细胞质SIRT1水平。模型组大鼠的胃内色素残留率高于阴性对照组,肠道推进率低于阴性对照组;模型组胃组织TUNEL阳性细胞数显著高于阴性对照组;模型组Bax、cleaved caspase-3水平均高于阴性对照组,而SIRT1、Bcl-2水平均低于阴性对照组(均P<0.05);3-MA可逆转模型组表现。结论:高糖能以LC3 II依赖性方式下调SIRT1水平,继而诱导GSMCs凋亡,促进DGP进展。 展开更多
关键词 糖尿病胃轻瘫 自噬 微管相关蛋白1轻链3 去乙酰化酶1 胃平滑肌细胞
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色素提取专用型萝卜新品种云紫萝1号的选育
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作者 陶婧 孙一丁 +7 位作者 陈瑶 杨龙 杨家秀 周晓波 汪骞 袁艺 薛娜 李石开 《中国蔬菜》 北大核心 2026年第1期207-210,F0003,共5页
云紫萝1号是以细胞质雄性不育系RR011A为母本,以自交系RR029为父本配制而成的色素提取专用型萝卜一代杂种。株型开展,平均株高47.0 cm,开展度52.4 cm;羽状深裂叶,先端形状尖,叶色绿,叶面刺毛少,叶基盘平,叶柄深紫色;肉质根纵切面钟形,... 云紫萝1号是以细胞质雄性不育系RR011A为母本,以自交系RR029为父本配制而成的色素提取专用型萝卜一代杂种。株型开展,平均株高47.0 cm,开展度52.4 cm;羽状深裂叶,先端形状尖,叶色绿,叶面刺毛少,叶基盘平,叶柄深紫色;肉质根纵切面钟形,肩部平,出、入土部分比例为1∶5,表皮和肉色均为紫色,平均根长10.3 cm,横径7.2 cm,单根质量280.4 g,萝卜红含量1.7%,萝卜红色素溶液最大吸收峰值531.5~532.0 nm。晚熟,播种至肉质根成熟约120 d(天),抽薹期约135 d(天),每667 m^(2)肉质根产量2000 kg左右、色素产量38 kg左右,适宜云南省海拔1500~2500 m萝卜产区秋冬季种植。 展开更多
关键词 萝卜 云紫萝1 一代杂种 色素提取专用型
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鸭星状病毒1型信阳株全基因组扩增及遗传进化分析
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作者 张敏 李迎晓 +5 位作者 张璐璐 何书海 曲哲会 秦东升 刘纪成 焦凤超 《中国畜牧兽医》 北大核心 2026年第2期959-972,共14页
【目的】了解信阳地区鸭星状病毒1型(Duck astrovirus type 1,DAstV1)流行株基因组的演化特征,为进一步研究信阳地区DAstV1的流行、遗传进化及致病特性提供参考依据。【方法】对某养殖场送检的病鸭进行禽腺病毒、禽星状病毒和鸭甲型肝... 【目的】了解信阳地区鸭星状病毒1型(Duck astrovirus type 1,DAstV1)流行株基因组的演化特征,为进一步研究信阳地区DAstV1的流行、遗传进化及致病特性提供参考依据。【方法】对某养殖场送检的病鸭进行禽腺病毒、禽星状病毒和鸭甲型肝炎病毒等12种常见病毒的PCR/RT-PCR筛查。采集病鸭肝脏组织,无菌处理后经卵黄囊途径接种10日龄SPF鸭胚,连续传代4次,并逐代收集尿囊液进行DAstV RT-PCR鉴定。对分离到的病毒进行全基因组测序,并对ORF1a、ORF1b和ORF2基因序列及其编码蛋白的氨基酸变异位点进行比对分析。【结果】送检病料筛查结果显示,禽星状病毒呈阳性。第1~4代鸭胚尿囊液中均呈DAstV1阳性,将该病毒命名为HN24XY06。第4代接种鸭胚全部死亡,死亡胚体发育不良且体表出血。HN24XY06基因组全长7 755 nt,包含ORF1a、ORF1b和ORF2 3个开放阅读框。序列比对和系统发育分析表明,HN24XY06属于DAstV1毒株,与山东分离株DAstV-SDZZ和DAstV-SDWF亲缘关系较近。ORF1a、ORF1b和ORF2蛋白的氨基酸序列分析显示,存在不同程度的突变,多发生在ORF1a编码的氨基酸序列中。【结论】本研究分离到了1株DAstV1,丰富了信阳地区DAstV1的分子流行病学资料,并为进一步研究DAstV1的致病机制奠定了基础。 展开更多
关键词 鸭星状病毒1型(DAstV1) 病毒分离与鉴定 全基因组扩增 遗传进化分析
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A New Method for Computing the 1-Dimensional Homology Group of a Given 2-Complex
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作者 李书超 冯艳钦 毛经中 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2003年第3期381-390,共10页
In [3], a vector space associate with a graph G: 'its cycle space' was described over the two element field Z2. Here we generalize the theory to the ring Z to compute 1-dimensional homology group of a given 2-... In [3], a vector space associate with a graph G: 'its cycle space' was described over the two element field Z2. Here we generalize the theory to the ring Z to compute 1-dimensional homology group of a given 2-complex with a combination of algebraic and graph-theoretic method. 展开更多
关键词 1-chain 1-cycle COMPLEX homology group.
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高山杜鹃‘红珍珠’×马缨杜鹃杂交F_(1)代表型性状遗传分析
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作者 解玮佳 宋杰 +3 位作者 彭绿春 张露 杨忠元 李世峰 《北方园艺》 北大核心 2026年第7期1-8,共8页
以高山杜鹃‘红珍珠’×马缨杜鹃的60棵F_(1)代植株为试材,采用相关性分析、主成分分析、聚类分析等统计学方法,对杂交群体的枝、叶、花等12个表型性状进行测定,对其遗传多样性进行研究,探索高山杜鹃杂交F_(1)代表型性状遗传变异规... 以高山杜鹃‘红珍珠’×马缨杜鹃的60棵F_(1)代植株为试材,采用相关性分析、主成分分析、聚类分析等统计学方法,对杂交群体的枝、叶、花等12个表型性状进行测定,对其遗传多样性进行研究,探索高山杜鹃杂交F_(1)代表型性状遗传变异规律,以期为高山杜鹃杂交育种亲本选配和优异种质筛选提供参考依据。结果表明:杂交后代的12个表型性状变异系数范围为13.74%~30.94%。株高、枝长、叶数、叶柄长、花序宽、花朵数呈趋中偏低遗传;花序高为趋中偏高遗传;叶面积、叶长、叶平均宽、叶最大宽为母性遗传。66对相关性分析中,极显著(P<0.01)正相关14对,极显著(P<0.01)负相关1对,显著(P<0.05)正相关2对。主成分分析结果可知,叶面积、叶长、叶平均宽、叶最大宽、叶柄长、花序宽、株高、叶数是区分亲本与杂交F_(1)代株系的主要指标。系统聚类将F_(1)代的60个单株分为3个类群,聚类结果充分反映了各类群的特征。 展开更多
关键词 高山杜鹃 杂交F_(1)代 表型性状 杂种优势 遗传分析
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2022-2024年四川省自贡市新报告HIV-1感染者基因亚型及治疗前耐药特征分析
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作者 张英 万晓宇 +4 位作者 肖丽 贺月 邓建平 袁丹 周玚 《疾病监测》 北大核心 2026年第1期47-53,共7页
目的了解四川省自贡市新报告HIV-1感染者基因亚型的流行特征及治疗前耐药情况,为制定个体化治疗方案和有效的干预措施提供科学依据。方法收集2022—2024年自贡市新报告HIV-1感染者血浆样本及人口学信息,扩增pol区获取基因序列,构建进化... 目的了解四川省自贡市新报告HIV-1感染者基因亚型的流行特征及治疗前耐药情况,为制定个体化治疗方案和有效的干预措施提供科学依据。方法收集2022—2024年自贡市新报告HIV-1感染者血浆样本及人口学信息,扩增pol区获取基因序列,构建进化树判定基因亚型,并上传序列至美国斯坦福大学HIV耐药数据库,分析耐药情况。以0.5%基因距离作为阈值构建分子传播网络,分析耐药传播特点及网络关联情况。结果共获得pol区基因序列1523条,基因亚型主要为CRF07_BC(52.26%)、CRF01_AE(22.72%)、CRF08_BC(16.41%)、CRF85_BC(4.01%);不同基因亚型的HIV-1感染者在年龄(χ^(2)=39.665,P<0.001)、文化程度(χ^(2)=10.657,P=0.031)、传播途径(χ^(2)=21.403,P=0.006)和耐药状态方面(χ^(2)=52.520,P<0.001)比较差异均有统计学意义。对1523例HIV样本进行的耐药性监测显示,共有173例样本出现不同程度的耐药,总耐药率为11.35%(173/1523)。非核苷类反转录酶抑制剂(NNRTIs)耐药率为7.81%(119/1523),核苷类反转录酶抑制剂耐药率为1.31%(20/1523),蛋白酶抑制剂耐药率为1.51%(23/1523)。NNRTIs耐药突变位点以K103和E138为主,K103N/KN/KNRS、E138A/EA/EG/EK/K在出现的组合突变位点中占比较高;按照0.5%基因距离计算,有705条序列入网(入网率46.29%),共形成150个分子簇,CRF07_BC亚型成簇率最高,存在2个耐药传播簇,Q58E和M46I为主要突变位点。此外,还监测到CRF85_BC亚型中存在的1个大型耐药传播簇有13个节点,E138A为主要突变位点。结论自贡市HIV-1感染者病毒基因亚型流行种类复杂,应关注重点传播分子簇,采取必要的干预措施,阻止HIV-1疫情的传播。同时,HIV-1感染者抗病毒治疗前耐药率达到中等水平,应把治疗前耐药监测纳入监测管理,通过对耐药突变位点的分析,明确不同亚型的耐药特点及其对治疗的影响。 展开更多
关键词 HIV-1感染者 治疗前耐药 基因亚型 分子网络
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大车前苷通过MAPK1/c-Myc轴调节内质网应激和线粒体损伤对卵巢癌细胞的影响和机制
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作者 雷燕 汤宇琴 +3 位作者 冯春 高悦 廉红梅 杜欣 《辽宁中医杂志》 北大核心 2026年第4期196-200,I0005-I0007,共8页
目的该研究旨在探讨大车前苷(plantamajoside,PMS)通过丝裂原活化蛋白激酶1(mitogen-Activated Protein Kinase 1,MAPK1)/c-Myc轴调控内质网应激和线粒体损伤进而参与卵巢癌(ovarian cancer,OC)进展的机制。方法使用不同浓度PMS干预SKOV... 目的该研究旨在探讨大车前苷(plantamajoside,PMS)通过丝裂原活化蛋白激酶1(mitogen-Activated Protein Kinase 1,MAPK1)/c-Myc轴调控内质网应激和线粒体损伤进而参与卵巢癌(ovarian cancer,OC)进展的机制。方法使用不同浓度PMS干预SKOV3细胞并将细胞分为Control组、顺铂阳性对照(DDP)组、PMS低剂量(PMS-L)组、PMS中剂量(PMS-M)组、PMS高剂量(PMS-H)组。CCK8检测人OC细胞SKOV3细胞活力,克隆形成实验检测细胞克隆形成能力,TUNEL检测细胞凋亡,Western blot检测SKOV3细胞内质网应激相关蛋白(p-PERK和CHOP)表达,JC-1检测试剂盒检测线粒体膜电位(mitochondrial Membrane Potential,MMP)水平,ROS检测试剂盒检测细胞内ROS水平。网络药理学分析得到PMS治疗OC的靶点,并建立MAPK1过表达细胞模型和c-Myc敲减细胞模型,分析MAPK1对OC细胞生长及内质网应激和线粒体损伤的影响和机制。建立异种移植瘤模型,评估PMS对体内OC的影响。结果相较于Control组,DDP和PMS干预均显著抑制OC细胞的活力与克隆形成能力,诱导细胞凋亡,并通过内质网应激和线粒体途径加重OC细胞损伤。与IOSE-80组相比,OC细胞中MAPK1水平显著升高。与PMS-H组相比,过表达MAPK1促进癌细胞生长,抑制PMS诱导的癌细胞损伤。相较于oe-MAPK1组,敲减c-Myc逆转过表达MAPK1对癌细胞的保护作用。动物实验结果发现,相较于Model组,PMS治疗抑制肿瘤生长,促进癌细胞内质网应激和线粒体损伤。结论PMS通过抑制OC细胞内MAPK1/c-Myc轴促进OC细胞内质网应激和线粒体损伤,进而改善OC进展。 展开更多
关键词 大车前苷 丝裂原活化蛋白激酶1 内质网应激 线粒体损伤 卵巢癌
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养精种玉汤调控SIRT1/PGC-1α信号通路改善卵巢储备功能减退大鼠线粒体功能及氧化应激损伤的机制
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作者 张萍 杨丽娟 +6 位作者 陈胜辉 姚文亮 周玉良 马玲 吴慧颖 徐燕文 周紫嫣 《中国实验方剂学杂志》 北大核心 2026年第7期46-55,共10页
目的:研究养精种玉汤对环磷酰胺诱导的卵巢储备功能减退(DOR)大鼠沉默信息调节因子1(SIRT1)/过氧化物酶体增殖物激活受体γ共激活因子-1α(PGC-1α)信号通路介导的线粒体生物发生与氧化应激损伤的影响,并探讨其改善卵巢储备功能及卵泡... 目的:研究养精种玉汤对环磷酰胺诱导的卵巢储备功能减退(DOR)大鼠沉默信息调节因子1(SIRT1)/过氧化物酶体增殖物激活受体γ共激活因子-1α(PGC-1α)信号通路介导的线粒体生物发生与氧化应激损伤的影响,并探讨其改善卵巢储备功能及卵泡发育的作用机制。方法:选取42只动情周期正常的8周龄雌性SD大鼠,随机分为空白组(7只)和造模组(35只)。造模组大鼠采用腹腔注射环磷酰胺(90 mg·kg^(-1))一次性造模,造模后连续观察7 d,通过动情周期紊乱标准判断造模成功。造模成功后,戊酸雌二醇组(0.09 mg·kg^(-1))及养精种玉汤高、中、低剂量组(19.98、9.99、5.00 g·kg^(-1))药物干预,空白组和模型组给予等体积蒸馏水灌胃,所有组别每日灌胃1次,连续干预4周。实验期间观察并记录各组大鼠的一般状态、体质量及卵巢湿质量,计算卵巢脏器指数。采用酶联免疫吸附测定法(ELISA)检测大鼠血清中促卵泡生成素(FSH)、黄体生成素(LH)、雌二醇(E_(2))及抗缪勒管激素(AMH)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)水平;苏木素-伊红(HE)染色观察卵巢组织形态学变化及卵泡发育状态;免疫荧光检测活性氧(ROS)表达水平;化学比色法检测卵巢组织中腺苷三磷酸(ATP)与丙二醛(MDA)含量;实时荧光定量聚合酶链式反应(Real-time PCR)检测线粒体DNA(mtDNA)拷贝数及SIRT1、PGC-1α、核呼吸因子1(NRF1)、线粒体转录因子A(TFAM)等关键基因的mRNA表达水平;蛋白免疫印迹法(Western blot)检测SIRT1、PGC-1α、NRF1、TFAM蛋白表达水平。结果:与空白组比较,模型组大鼠动情周期紊乱,体质量及卵巢指数明显下降(P<0.05);卵巢组织病理学表现为皮质变薄、结构疏松、原始卵泡及生长卵泡数量均显著减少(P<0.01);血清FSH、LH水平显著升高(P<0.01),E_(2)、AMH水平明显降低(P<0.05,P<0.01);卵巢组织中ATP含量及mtDNA拷贝数显著下降(P<0.01),ROS表达增强,MDA水平升高,SOD和GSH-Px活性明显降低(P<0.05,P<0.01);SIRT1、PGC-1α、NRF1、TFAM的mRNA及蛋白表达水平均明显下调(P<0.05,P<0.01)。治疗后,与模型组比较,养精种玉汤各剂量组大鼠体质量及卵巢指数明显回升(P<0.05);血清中E_(2)和AMH水平明显升高,FSH和LH水平明显下降(P<0.05,P<0.01);卵巢组织ATP含量和mtDNA拷贝数明显上调,ROS和MDA水平明显下降,抗氧化酶SOD、GSH-Px活性明显增强(P<0.05,P<0.01);SIRT1/PGC-1α/NRF1/TFAM信号通路相关基因与蛋白表达水平均较模型组明显上调(P<0.05,P<0.01);HE染色显示,各治疗组卵巢结构逐步恢复完整,原始卵泡及生长卵泡数量明显增加(P<0.05,P<0.01),颗粒细胞排列整齐,卵巢功能改善明显。结论:养精种玉汤可能通过激活SIRT1/PGC-1α信号通路,促进线粒体生物发生,提升线粒体功能,减轻氧化应激损伤,从而改善卵巢储备功能减退大鼠的卵巢功能。 展开更多
关键词 养精种玉汤 卵巢储备功能减退 沉默信息调节因子1(SIRT1)/过氧化物酶体增殖物激活受体γ共激活因子-1α(PGC-1α)信号通路 氧化应激 线粒体
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