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Strategic and Regional Investigation of the Exact Controllability of the Vibrating Plate Equation on a Regular Domain
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作者 Mouhamadou NGOM Cheikh SECK 《Journal of Mathematical Research with Applications》 2026年第1期134-142,共9页
In this paper,we define for the trace operator,the solution of certain models of vibrating plates standards with initial data in a strategic region spaces of weak regularities.Indeed,we know that the notion of regiona... In this paper,we define for the trace operator,the solution of certain models of vibrating plates standards with initial data in a strategic region spaces of weak regularities.Indeed,we know that the notion of regional controllability is more adapted to systems described by dynamic systems.Regional controllability results in a strategic area were established for vibrating plates by the Hilbertian Uniqueness Method. 展开更多
关键词 exact controllability vibrating plates strategic regional control Hilbert uniqueness method
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基于UPLC-Q Exactive Orbitrap-HRMS技术和网络药理学探讨黄连上清丸解热抗炎的活性成分及其作用机制 被引量:2
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作者 曲婷丽 王二兵 +3 位作者 张楠 许信学 周小雪 高耀 《药物评价研究》 北大核心 2025年第2期394-415,共22页
目的 基于超高效液相色谱串联四极杆静电场轨道阱质谱(UPLC-Q Exactive Orbitrap-HRMS)技术、网络药理学和分子对接探究黄连上清丸解热抗炎的活性成分及其作用机制。方法 根据质谱信息、对照品裂解规律及参考文献资料对黄连上清丸中的... 目的 基于超高效液相色谱串联四极杆静电场轨道阱质谱(UPLC-Q Exactive Orbitrap-HRMS)技术、网络药理学和分子对接探究黄连上清丸解热抗炎的活性成分及其作用机制。方法 根据质谱信息、对照品裂解规律及参考文献资料对黄连上清丸中的化学成分进行指认;利用SwissADME数据库筛选黄连上清丸中的成药性成分,PharmMapper数据库获取成药性成分相关作用靶点;利用Gene cards和Disgenet数据库筛选解热、炎症相关靶点;对得到的成分作用靶点与疾病相关靶点取交集,获得黄连上清丸发挥解热抗炎作用的潜在靶点,采用Cytoscape 3.10.1软件构建“成分-靶点-疾病-复方”网络,分析活性成分;将共有靶点导入STRING网站,构建蛋白质-蛋白质相互作用(PPI)网络,分析关键靶点;通过微生信网站对关键靶点进行基因本体(GO)和京都基因与基因组百科全书(KEGG)富集分析;将活性成分与关键靶点进行分子对接验证;通过建立HPLC指纹图谱,控制黄连上清丸的质量。结果 从黄连上清丸中共鉴定144个化合物,其中黄酮类58个、生物碱类17个、环烯醚萜类7个、木脂素类4个、色原酮类8个、蒽醌类7个、香豆素类2个、皂苷类5个、有机酸类5个、酚酸类7个、苯丙素类9个、苯乙醇苷类4个、糖类2个、内酯类1个,以及其他类8个。黄连上清丸发挥解热抗炎作用的潜在作用靶点有218个,涉及2 036个生物过程、119个细胞组分、281个分子功能和155条信号通路。筛选得到莲心季铵碱、甘草宁G、大黄素、氧化小檗碱、甘草素、大黄素甲醚、花椒毒酚、粘毛黄芩素Ⅲ等12个潜在活性成分,胰岛素(INS)、RAC-α丝氨酸/苏氨酸蛋白激酶(AKT1)、表皮生长因子受体(EGFR)、热休克蛋白HSP 90-α(HSP90AA1)、基质金属蛋白酶-9(MMP9)等10个关键靶蛋白,以及Ras信号通路、叉头框蛋白O信号通路、Rap1信号通路、丝裂原活化蛋白激酶信号通路等信号通路。12个潜在活性成分与关键靶点有较强的结合活性。建立的指纹图谱可指认黄连上清丸中的8个活性成分。结论 黄连上清丸可能是通过莲心季铵碱、甘草宁G、大黄素、氧化小檗碱、甘草素、大黄素甲醚等活性成分,作用于INS、AKT1、EGFR、HSP90AA1、MMP9等关键靶点,通过Ras信号通路、叉头框蛋白O信号通路、Rap1信号通路、丝裂原活化蛋白激酶信号通路等信号通路,发挥解热抗炎作用。 展开更多
关键词 黄连上清丸 UPLC-Q Exactive Orbitrap-HRMS 网络药理学 抗炎 解热 莲心季铵碱 大黄素 氧化小檗碱
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朱砂七化学成分的UHPLC-Q Exactive Focus MS分析
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作者 后亚芳 任慧 +4 位作者 崔小敏 鲁文静 胡静 曲彤 陈志永 《中药材》 北大核心 2025年第5期1186-1192,共7页
目的:基于UHPLC-Q Exactive Focus MS技术对朱砂七的化学成分进行快速识别和鉴定。方法:采用Thermo Accucore aQ RP18色谱柱(150 mm×2.1 mm,2.6μm);甲醇-0.1%甲酸水溶液为流动相,梯度洗脱;流速0.3 mL/min;柱温30℃。采用电喷雾离... 目的:基于UHPLC-Q Exactive Focus MS技术对朱砂七的化学成分进行快速识别和鉴定。方法:采用Thermo Accucore aQ RP18色谱柱(150 mm×2.1 mm,2.6μm);甲醇-0.1%甲酸水溶液为流动相,梯度洗脱;流速0.3 mL/min;柱温30℃。采用电喷雾离子源,正、负离子模式扫描,扫描范围为m/z 80~1200。结果:从朱砂七中共解析出53个化学成分,包括蒽醌类17个,色原酮类5个,二苯乙烯类6个,萘苷类4个,黄烷类4个,酚酸类15个,其他类2个。结论:该方法可快速对朱砂七中化学成分进行定性分析,为后续朱砂七药效物质研究及质量评价提供依据。 展开更多
关键词 朱砂七 UHPLC-Q Exactive Focus MS 蒽醌类 色原酮类 二苯乙烯类
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基于UPLC-Q Exactive MS的准噶尔柳花化学成分分析及抗脂肪肝作用体外机制研究
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作者 余璐 董静茹 +5 位作者 王兰兰 李好 戴雪梅 郭新勇 李静 张丽 《天然产物研究与开发》 北大核心 2025年第4期647-658,共12页
探究准噶尔柳花的活性成分及其改善代谢功能障碍相关脂肪性肝病(metabolic dysfunction-associated steatotic liver disease,MASLD)的作用机制。研究采用超高效液相色谱-四极杆-静电场轨道阱质谱(UPLC-Q Exactive MS)技术分析了准噶尔... 探究准噶尔柳花的活性成分及其改善代谢功能障碍相关脂肪性肝病(metabolic dysfunction-associated steatotic liver disease,MASLD)的作用机制。研究采用超高效液相色谱-四极杆-静电场轨道阱质谱(UPLC-Q Exactive MS)技术分析了准噶尔柳花中的主要化学成分,共鉴定出36个化合物及其含量,涵盖黄酮类、多酚类、酸类及其他生物活性成分,其中木犀草苷、儿茶素、木犀草素等生物活性成分的含量较为丰富。通过游离脂肪酸(free fatty acids,FFA)诱导的HepG2细胞脂肪堆积模型,研究了准噶尔柳花提取物(Salix songarica flower extract,SSE)对MASLD的防治效果。实验结果显示,SSE显著地降低了细胞内的总胆固醇(total cholesterol,TC)和甘油三酯(triglyceride,TG)含量,减少了脂滴积累,并改善了肝损伤标志物天冬氨酸氨基转移酶(aspartate aminotransferase,AST)、丙氨酸氨基转移酶(alanine aminotransferase,ALT)水平。同时,SSE还显著地降低了氧化损伤标志物丙二醛(malondialdehyde,MDA)的含量,提高了超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalase,CAT)和还原型谷胱甘肽(reduced glutathione,GSH)水平。机制研究进一步揭示,SSE通过上调法尼醇X受体(farnesoid X receptor,FXR)、胆盐输出泵(bile salt export pump,BSEP)和胆固醇7α-羟化酶(cholesterol 7α-hydroxylase,CYP7A1)的mRNA表达水平,调节了肝细胞脂质代谢。综上,SSE在MASLD防治中展现了显著潜力,具备抗氧化和调节脂质代谢的功能,提供了新的预防与治疗MASLD的可能性,尤其在食品和保健品领域的应用前景广阔。 展开更多
关键词 脂肪肝 植物提取物 准噶尔柳花 UPLC-Q Exactive MS
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基于UPLC-Q-Exactive Focus MS/MS和网络药理学的枣仁安神胶囊治疗失眠的潜在质量标志物预测
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作者 曲彤 张红 +6 位作者 李宁 鲁文静 崔小敏 胡静 梁超 任慧 陈志永 《药物评价研究》 北大核心 2025年第11期3206-3225,共20页
目的运用超高效液相色谱-四极杆/静电场轨道阱高分辨质谱(UPLC-Q-Exactive Focus MS/MS)技术鉴定枣仁安神胶囊化学成分,结合网络药理学和分子对接对枣仁安神胶囊治疗失眠的质量标志物(Q-Marker)进行预测。方法采用UPLC-Q-Exactive Focus... 目的运用超高效液相色谱-四极杆/静电场轨道阱高分辨质谱(UPLC-Q-Exactive Focus MS/MS)技术鉴定枣仁安神胶囊化学成分,结合网络药理学和分子对接对枣仁安神胶囊治疗失眠的质量标志物(Q-Marker)进行预测。方法采用UPLC-Q-Exactive Focus MS/MS技术在正、负离子模式下对枣仁安神胶囊中化学成分进行定性分析;将所得成分导入SwissADME数据库检索成分靶点;利用GeneCards、OMIM数据库收集失眠相关疾病靶点,取交集后利用Cytoscape 3.7.2软件构建“成分-疾病-靶点”网络,STRING数据库建立蛋白质-蛋白质相互作用(PPI)网络并筛选核心成分与核心靶点。利用DAVID数据库对共同靶点进行基因本体(GO)和京都基因与基因组百科全书(KEGG)通路富集分析,借助分子对接预测核心成分和关键靶点的结合能力,初步探索枣仁安神胶囊的Q-Marker。结果通过UPLC-Q-Exactive Focus MS/MS共鉴定了枣仁安神胶囊中147种化学成分,结合数据库得到35个具有作用靶点的活性成分,644个与失眠相关靶点。其中,戈米辛E、表丹参隐螺内酯、五味子酯乙、五味子醇甲、五味子醇乙、五味子酯甲、木兰箭毒碱为枣仁安神胶囊治疗失眠的核心成分,蛋白激酶B(AKT1)、肿瘤坏死因子(TNF)、信号传导子及转录激活子3(STAT3)、B细胞淋巴瘤/白血病-2蛋白(BCL2)、胱天蛋白酶3(CASP3)为枣仁安神胶囊治疗失眠的核心靶点。作用于失眠与神经退行性变的途径、生长激素的合成、趋化因子信号通路等15条信号通路。分子对接结果表丹参隐螺内酯、戈米辛E、五味子醇乙、木兰箭毒碱4个核心成分与相关核心靶点的结合活性较好可作为枣仁安神胶囊的Q-Marker。结论预测枣仁安神胶囊可能通过表丹参隐螺内酯、戈米辛E、五味子醇乙、木兰箭毒碱等关键成分,作用于AKT1、TNF、STAT3和BCL2等靶点,通过干预neurodegeneration-multiple diseases、Chemokine、FoxO等通路发挥治疗失眠的作用。 展开更多
关键词 枣仁安神胶囊 超高效液相色谱-四极杆/静电场轨道阱高分辨质谱(UPLC-Q Exactive Focus MS/MS) 网络药理学 分子对接 质量标志物 表丹参隐螺内酯 戈米辛E 五味子醇乙 木兰箭毒碱
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基于UHPLC-Q Exactive Focus MS/MS方法辨析小陷胸汤的体内成分分布
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作者 后亚芳 刘园 +5 位作者 任慧 胡静 崔小敏 曲彤 杜霞 陈志永 《特产研究》 2025年第2期120-127,共8页
本文旨在研究小陷胸汤在大鼠体内的成分及分布特征。试验采用超高效液相色谱四极杆/静电场轨道阱高分辨质谱法(UHPLC-Q Exactive Focus MS/MS)分析大鼠血浆、组织及排泄物中的化学成分,通过比对小陷胸汤、空白血浆、含药血浆、组织及排... 本文旨在研究小陷胸汤在大鼠体内的成分及分布特征。试验采用超高效液相色谱四极杆/静电场轨道阱高分辨质谱法(UHPLC-Q Exactive Focus MS/MS)分析大鼠血浆、组织及排泄物中的化学成分,通过比对小陷胸汤、空白血浆、含药血浆、组织及排泄物的图谱差异,解析小陷胸汤经大鼠灌胃后不同时间点血浆、组织及排泄物中的化学成分及代谢产物。给药后30、60、90、120min的大鼠血浆样品中分别检出12、14、12、7种小陷胸汤的入血化学成分和3、8、3和5个入血代谢产物,其中成分包括生物碱类15种、核苷类2种、氨基酸类1种、有机酸类2种、糖醛类1种、挥发油及油脂类1种。代谢产物主要为小檗碱、药根碱、缬氨酸、烟酸等化合物,通过葡萄糖醛酸化、硫酸酯化、甲基化等代谢途径产生的代谢物,以Ⅱ相代谢为主。从大鼠的心、肝、脾、肺、肾、脑、粪和尿中分别检测到10、10、6、11、12、8、23、23种小陷胸汤的化学成分。本研究系统地分析了小陷胸汤在体内的分布特征,为其药效物质基础及作用机制研究提供了重要依据。 展开更多
关键词 UHPLC-Q Exactive FocusMS/MS 小陷胸汤 化学成分 体内分布 代谢产物 药效物质
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Research on multi-wave joint elastic modulus inversion based on improved quantum particle swarm optimization 被引量:2
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作者 Peng-Qi Wang Xing-Ye Liu +4 位作者 Qing-Chun Li Yi-Fan Feng Tao Yang Xia-Wan Zhou Xu-Kun He 《Petroleum Science》 2025年第2期670-683,共14页
Young's modulus and Poisson's ratio are crucial parameters for reservoir characterization and rock brittleness evaluation.Conventional methods often rely on indirect computation or approximations of the Zoeppr... Young's modulus and Poisson's ratio are crucial parameters for reservoir characterization and rock brittleness evaluation.Conventional methods often rely on indirect computation or approximations of the Zoeppritz equations to estimate Young's modulus,which can introduce cumulative errors and reduce the accuracy of inversion results.To address these issues,this paper introduces the analytical solution of the Zoeppritz equation into the inversion process.The equation is re-derived and expressed in terms of Young's modulus,Poisson's ratio,and density.Within the Bayesian framework,we construct an objective function for the joint inversion of PP and PS waves.Traditional gradient-based algorithms often suffer from low precision and the computational complexity.In this study,we address limitations of conventional approaches related to low precision and complicated code by using Circle chaotic mapping,Levy flights,and Gaussian mutation to optimize the quantum particle swarm optimization(QPSO),named improved quantum particle swarm optimization(IQPSO).The IQPSO demonstrates superior global optimization capabilities.We test the proposed inversion method with both synthetic and field data.The test results demonstrate the proposed method's feasibility and effectiveness,indicating an improvement in inversion accuracy over traditional methods. 展开更多
关键词 Young's modulus PP-PS joint inversion Exact Zoeppritz Pre-stack inversion QPSO
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一种新型测量瓦里安碳纤维Exact IGRT Couch HU值的方法及临床应用
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作者 王广善 张同梅 +2 位作者 邢彦 牛亦婷 金见悦 《中国医学物理学杂志》 2025年第9期1130-1135,共6页
目的:寻找一种新方法测量瓦里安Exact IGRT Couch表面碳纤维材料的HU值,并在计划系统中创建治疗床模型,以修正治疗床对射线剂量的衰减。方法:通过两种不同的射野组合对瓦里安Exact IGRT Couch床头薄端和中间中等厚度处对射线剂量的衰减... 目的:寻找一种新方法测量瓦里安Exact IGRT Couch表面碳纤维材料的HU值,并在计划系统中创建治疗床模型,以修正治疗床对射线剂量的衰减。方法:通过两种不同的射野组合对瓦里安Exact IGRT Couch床头薄端和中间中等厚度处对射线剂量的衰减进行测量,得到射线穿治疗床和不穿治疗床两种情况下的剂量偏差。在治疗计划系统(TPS)中定义多组不同的床表面材料的HU值,按照与测量相同的条件计算射线穿床和不穿床两种情况下剂量差异。通过数据比对分析,找到与实测相对应的治疗床材料的HU值。结果:两对穿射野在薄端处的衰减为-2.49%~-1.69%,在中等厚度处的衰减为-3.43%~-2.23%;多个斜入射射野在薄端处的衰减为-3.12%~-2.17%,在中等厚度处的衰减为-3.59%~-2.86%。当TPS中床模型表面和内部HU值分别定义为-500和-960时,两对穿射野在薄端处的衰减为-2.57%~-1.53%,在中等厚度处的衰减为-3.28%~-2.18%,多个斜入射射野在薄端处的衰减为-3.12%~-2.21%,在中等厚度处的衰减为-3.42%~-2.43%,与实测数值比较吻合。40个验证计划在薄端和中等厚度处实测点剂量与TPS计算剂量平均差异分别为0.90%和0.89%。结论:该新型测量方法可以预测Exact IGRT Couch表面碳纤维材料和内部泡沫材料的HU值,在TPS中定义床模型两种材料的HU值为-500和-960校正治疗床对射线的衰减,从而提高靶区和危及器官的剂量精度。 展开更多
关键词 Exact IGRT Couch 治疗床 衰减 HU值 床模型
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基于UPLC-Q Exactive Orbitrap MS技术解析“国槐”木酒海贮存老熟金徽酒难挥发性组分特征
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作者 冯雨枫 张智良 +5 位作者 黄小东 唐亮 赵江林 郭涛红 徐岩 陈双 《酿酒科技》 2025年第9期50-57,共8页
“国槐”木酒海作为一种生物材料制作而成的贮酒容器,在贮存老熟过程中会与酒体产生化学反应与物质交换。为解析木酒海贮存老熟金徽酒的难挥发性组分特征,探究其中具有生理活性的物质,本研究采用超高效液相色谱系统与四极杆-静电场轨道... “国槐”木酒海作为一种生物材料制作而成的贮酒容器,在贮存老熟过程中会与酒体产生化学反应与物质交换。为解析木酒海贮存老熟金徽酒的难挥发性组分特征,探究其中具有生理活性的物质,本研究采用超高效液相色谱系统与四极杆-静电场轨道阱高分辨质谱仪联用(UPLC-Q Exactive Orbitrap MS),对木酒海贮存的金徽酒中的难挥发性组分进行分析并探索其功能成分。结果显示,在木酒海贮酒中共鉴定出222种难挥发性组分,其中105种具有生理活性,主要包括19种脂肪酰基(13种高级脂肪酸)、15种羧酸及其衍生物(13种氨基酸)、14种苯及其衍生物、8种甾体化合物、5种异戊烯醇酯类、3种酚类、2种黄酮和异黄酮类等。进一步对木酒海贮酒中的难挥发性组分含量进行相对定量,研究并分析木酒海贮酒中的难挥发性组分含量特点及物质来源。本研究有助于促进对木酒海贮酒难挥发性组分的认识,为全面解析其风味组分和探索其功能成分提供一定的研究基础。 展开更多
关键词 木酒海 金徽酒 难挥发性组分 UPLC-Q Exactive Orbitrap MS
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Nature of the 1/3 Magnetization Plateau in Spin-1/2 Kagome Antiferromagnets
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作者 Li-Wei He Xinzhe Wang +1 位作者 Shun-Li Yu Jian-Xin Li 《Chinese Physics Letters》 2025年第9期163-168,共6页
We investigate the origin of the 1/3 magnetization plateau in the S=1/2 kagome antiferromagnetic Heisenberg model using the variational Monte Carlo and exact diagonalization methods,to account for the recent experimen... We investigate the origin of the 1/3 magnetization plateau in the S=1/2 kagome antiferromagnetic Heisenberg model using the variational Monte Carlo and exact diagonalization methods,to account for the recent experimental observations in YCu_(3)(OH)_(6+x)Br_(3-x)and YCu_(3)(OD)_(6+x)Br_(3-x).We identify three degenerate valencebond-solid(VBS)states forming a√3×√3 unit cell.These states exhibit David-star patterns in the spin moment distribution with only two fractional values-1/3 and 2/3,and are related through translational transformations.While the spin correlations in these VBS states are found to be short-range,resembling a quantum spin liquid,we show that they have a vanishing topological entanglement entropy and thus are topologically trivial many-body states.Our theoretical results provide strong evidence that the 1/3 magnetization plateau observed in recent experiments arises from these√3×√3 VBS states with fractional spin moments. 展开更多
关键词 kagome antiferromagnetic heisenberg model variational monte carlo spin moment distribution valencebond solid states exact diagonalization magnetization plateau spin kagome antiferromagnets exact diagonalization methodsto
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In-Plane Static Analysis of Curved Nanobeams Using Exact-Solution-Based Finite Element Formulation
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作者 Omer Ekim Genel Hilal Koc Ekrem Tufekci 《Computers, Materials & Continua》 2025年第2期2043-2059,共17页
Due to their superior properties, the interest in nanostructures is increasing today in engineering. This study presents a new two-noded curved finite element for analyzing the in-plane static behaviors of curved nano... Due to their superior properties, the interest in nanostructures is increasing today in engineering. This study presents a new two-noded curved finite element for analyzing the in-plane static behaviors of curved nanobeams. Opposite to traditional curved finite elements developed by using approximate interpolation functions, the proposed curved finite element is developed by using exact analytical solutions. Although this approach was first introduced for analyzing the mechanical behaviors of macro-scale curved beams by adopting the local theory of elasticity, the exact analytical expressions used in this study were obtained from the solutions of governing equations that were expressed via the differential form of the nonlocal theory of elasticity. Therefore, the effects of shear strain and axial extension included in the analytical formulation are also inherited by the curved finite element developed here. The rigidity matrix and the consistent force vector are developed for a circular finite element. To demonstrate the applicability of the method, static analyses of various curved nanobeams subjected to different boundary conditions and loading scenarios are performed, and the obtained results are compared with the exact analytical ones. The presented study provides an accurate and low computational cost method for researchers to investigate the in-plane static behavior of curved nanobeams. 展开更多
关键词 Nonlocal elasticity finite element exact solution static analysis nanobeam curved
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Cerebral cortex contributions to Parkinson's disease tremor:what exactly generates the tremor?
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作者 Manuel Bange Hao Ding Muthuraman Muthuraman 《Neural Regeneration Research》 2025年第12期3535-3536,共2页
Pathological tremor is one of the cardinal symptoms in Parkinson's disease (PD).Tremor is comprised of involuntary,rhythmic,a nd oscillating movements that can vary according to the circumstances under which they ... Pathological tremor is one of the cardinal symptoms in Parkinson's disease (PD).Tremor is comprised of involuntary,rhythmic,a nd oscillating movements that can vary according to the circumstances under which they occur,the body parts that are involved,and the frequency at which they present.For example,tremors can be mild to severe,are stress sensitive,and can affect arms,legs,or the head (Dirkx and Bologna,2022). 展开更多
关键词 TREMOR CORTEX EXACTLY
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Periodic solutions,breather,lump and interaction solutions of a generalized(2+1)-dimensional Hirota bilinear equation via the bilinear neural network method
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作者 Zhao Zhao Bo Ren 《Communications in Theoretical Physics》 2025年第3期1-11,共11页
The main focus of this paper is to address a generalized(2+1)-dimensional Hirota bilinear equation utilizing the bilinear neural network method.The paper presents the periodic solutions through a single-layer model of... The main focus of this paper is to address a generalized(2+1)-dimensional Hirota bilinear equation utilizing the bilinear neural network method.The paper presents the periodic solutions through a single-layer model of[3-4-1],followed by breather,lump and their interaction solutions by using double-layer models of[3-3-2-1]and[3-3-3-1],respectively.A significant innovation introduced in this work is the computation of periodic cross-rational solutions through the design of a novel[3-(2+2)-4-1]model,where a specific hidden layer is partitioned into two segments for subsequent operations.Three-dimensional and density figures of the solutions are given alongside an analysis of the dynamics of these solutions. 展开更多
关键词 bilinear transformation BNNM double-layer model exact analytical solution
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Conservation Laws and Particular Solutions for a Keller-Segel Model
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作者 Luyun Chen Jie Lou 《Advances in Pure Mathematics》 2025年第2期107-118,共12页
This work focuses on a Keller-Segel chemotaxis model, with an emphasis on its conservation laws. Through a new approach combined with the multiplier method, called the mixed method, we obtain conservation vectors that... This work focuses on a Keller-Segel chemotaxis model, with an emphasis on its conservation laws. Through a new approach combined with the multiplier method, called the mixed method, we obtain conservation vectors that are related and unrelated to symmetric information. In addition, some exact solutions with particular forms are obtained according to the method of conservation laws. These particular solutions are different from the group-invariant solutions. 展开更多
关键词 Keller-Segel Model Conservation Laws Mixed Method Exact Solutions
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Exact solutions for the transcritical Riemann problem of two-parameter fluids
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作者 Haotong BAI Yixin YANG +2 位作者 Wenjia XIE Dejian LI Mingbo SUN 《Applied Mathematics and Mechanics(English Edition)》 2025年第12期2385-2406,共22页
Transcritical and supercritical fluids widely exist in aerospace propulsion systems,such as the coolant flow in the regenerative cooling channels of scramjet engines.To numerically simulate the coolant flow,we must ad... Transcritical and supercritical fluids widely exist in aerospace propulsion systems,such as the coolant flow in the regenerative cooling channels of scramjet engines.To numerically simulate the coolant flow,we must address the challenges in solving Riemann problems(RPs)for real fluids under complex flow conditions.In this study,an exact numerical solution for the one-dimensional RP of two-parameter fluids is developed.Due to the comprehensive resolution of fluid thermodynamics,the proposed solution framework is suitable for all forms of the two-parameter equation of state(EoS).The pressure splitting method is introduced to enable parallel calculation of RPs across multiple grid points.Theoretical analysis demonstrates the isentropic nature of weak waves in two-parameter fluids,ensuring that the same mathematical properties as ideal gas could be applied in Newton's iteration.A series of numerical cases validate the effectiveness of the proposed method.A comparative analysis is conducted on the exact Riemann solutions for the real fluid EoS,the ideal gas EoS,and the improved ideal gas EoS under supercritical and transcritical conditions.The results indicate that the improved one produces smaller errors in the calculation of momentum and energy fluxes. 展开更多
关键词 two-parameter fluid Riemann problem(RP) exact solution supercritical fluid pressure splitting transcritical fluid
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On shape coexistence and possible shape isomers of nuclei around^(172)Hg
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作者 Xin Guan Jing Guo +2 位作者 Qi-Wen Sun Bożena Nerlo-Pomorska Krzysztof Pomorski 《Nuclear Science and Techniques》 2025年第7期191-203,共13页
This study explores the phenomenon of shape coexistence in nuclei around^(172)Hg,with a focus on the isotopes^(170)Pt,^(172)Hg,and^(174)Pb,as well as the^(170)Pt to^(180)Pt isotopic chain.Utilizing a macro-microscopic... This study explores the phenomenon of shape coexistence in nuclei around^(172)Hg,with a focus on the isotopes^(170)Pt,^(172)Hg,and^(174)Pb,as well as the^(170)Pt to^(180)Pt isotopic chain.Utilizing a macro-microscopic approach that incorporates the Lublin-Strasbourg Drop model combined with a Yukawa-Folded potential and pairing corrections,we analyze the potential energy surfaces(PESs)to understand the impact of pairing interaction.For^(170)Pt,the PES exhibited a prolate ground state,with additional triaxial and oblate-shaped isomers.In^(172)Hg,the ground-state deformation transitions from triaxial to oblate with increasing pairing interaction,demonstrating its nearlyγ-unstable nature.Three shape isomers(prolate,triaxial,and oblate)were observed,with increased pairing strength leading to the disappearance of the triaxial isomer.^(174)Pb exhibited a prolate ground state that became increasingly spherical with stronger pairing.While shape isomers were present at lower pairing strengths,robust shape coexistence was not observed.For realistic pairing interaction,the ground-state shapes transitioned from prolate in^(170)Pt to a coexistence ofγ-unstable and oblate shapes in^(172)Hg,ultimately approaching spherical symmetry in^(174)Pb.A comparison between Exact and Bardeen-Cooper-Schrieffer(BCS)pairing demonstrated that BCS pairing tends to smooth out shape coexistence and reduce the depth of the shape isomer,leading to less pronounced deformation features.The PESs for even-even^(170)-180 Pt isotopes revealed significant shape evolution.^(170)Pt showed a prolate ground state,whereas^(172)Pt exhibited both triaxial and prolate shape coexistence.In^(174)Pt,the ground state was triaxial,coexisted with a prolate minimum.For^(176)Pt,aγ-unstable ground state coexists with a prolate minimum.By 178 Pt and 180Pt,a dominant prolate minimum emerged.These results highlight the role of shape coexistence andγ-instability in the evolution of nuclear structure,especially in the mid-shell region.These findings highlight the importance of pairing interactions in nuclear deformation and shape coexistence,providing insights into the structural evolution of mid-shell nuclei. 展开更多
关键词 Macro-micro-model Shape coexistence Shape isomers Exact and BCS pairing solutions
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Gravitational deflection of light in the polaraxis plane of a moving Kerr–Newman black hole
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作者 Xuan Wang Wenbin Lin +1 位作者 Bo Yang Guansheng He 《Communications in Theoretical Physics》 2025年第7期133-141,共9页
The gravitational deflection of light signals restricted in the polar-axis plane of a moving Kerr–Newman(KN)black hole with a constant velocity along the polar axis is studied within the second post-Minkowskian(PM)ap... The gravitational deflection of light signals restricted in the polar-axis plane of a moving Kerr–Newman(KN)black hole with a constant velocity along the polar axis is studied within the second post-Minkowskian(PM)approximation.For this purpose,the Lorentz boosting technique is adopted to obtain the exact metric of a moving KN black hole with an arbitrary constant velocity in Kerr–Schild coordinates for the first time.Based on the weak field limit of the exact metric,we then derive the equations of motion of test particles constrained in the polaraxis plane of a moving KN source whose velocity is along the polar axis and collinear with its angular momentum.An iterative technique is utilized subsequently in the calculations of the null deflection angle up to the 2PM order caused by the moving lens,and this deflection angle is found to be spin-independent.Finally,we discuss the influence of the motion of the lens on the gravitational deflection and estimate the possibility of detecting this kinematical effect.Our work might be helpful for future astronomical observations. 展开更多
关键词 black holes exact metric gravitational lens
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Exact P-wave reflection and transmission coefficients for horizontal transversely isotropic media at an imperfectly welded contact interface under in-situ horizontal stress
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作者 Xin-Peng Pan Cheng-Xu Lu +1 位作者 Hao-Wen Xu Da-Zhou Zhang 《Petroleum Science》 2025年第4期1497-1512,共16页
A comprehensive understanding of exact seismic P-wave reflection and transmission(R/T)coefficients at imperfectly welded or non-welded contact interfaces holds paramount importance in the realm of seismic exploration.... A comprehensive understanding of exact seismic P-wave reflection and transmission(R/T)coefficients at imperfectly welded or non-welded contact interfaces holds paramount importance in the realm of seismic exploration.Nonetheless,scant attention has been devoted in previous literature to the investigation of stress-dependent exact R/T coefficients in horizontal transversely isotropic(HTI)media,characterized by a horizontal symmetry axis,at such interfaces.Addressing this scholarly gap,we present exact R/T coefficient formulations specifically tailored to an imperfectly welded contact interface separating two HTI media under the influence of in-situ horizontal stress.We begin by deriving the equation of motion for a stressed HTI medium,utilizing the theoretical framework of acoustoelasticity to examine the impact of in-situ horizontal stress on the overarching elastic properties of HTI media.Precise boundary conditions are then established at the imperfectly welded contact interface by applying generalized stress-strain relationships and linear-slip theory,with the influence of in-situ horizontal stress on the interface further explored through the linear-slip model.By integrating these elements with the seismic wave displacement equation,we derive exact R/T coefficient formulations applicable to an imperfectly welded contact interface between two HTI media.Numerical analyses are conducted to elucidate the effects of in-situ horizontal stress on critical parameters such as rock density,seismic wave velocity,Thomsen-type anisotropy parameters,R/T coefficients,and seismic reflection responses at the imperfectly welded contact interface.Furthermore,the proposed formulations are frequency-dependent,with the imperfectly welded contact interface acting as a frequency-selective filter for both reflected and transmitted waves.Notably,under conditions of sufficiently large incident angles,the sensitivity of R/T coefficients to key influencing factors increases significantly.The derived R/T coefficient formulations and the accompanying numerical results offer valuable insights for fracture characterization,stress-dependent parameter inversion,and in-situ stress detection. 展开更多
关键词 Exact R/T coefficients Acoustoelasticity theory Linear-slip theory Stress-dependent parameters Frequency-dependent formulations`
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Functional Solutions,Multi Line Solitons and Multiple Pole Solutions of the Generalized(2+1)-dimensional Kaup-Kupershmidt Equation
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作者 Linlin Gui Yufeng Zhang 《Communications in Mathematical Research》 2025年第2期103-121,共19页
The(2+1)-dimensional integrable generalization of the Kaup-Kuper-shmidt(KK)equation is solved by the inverse spectral transform method in this paper.Several new long derivative operators V_(x),V_(y) and V_(t) and the ... The(2+1)-dimensional integrable generalization of the Kaup-Kuper-shmidt(KK)equation is solved by the inverse spectral transform method in this paper.Several new long derivative operators V_(x),V_(y) and V_(t) and the kernel functions K of ■-problem are introduced to construct a type of general solution of the KK equation.Based on these,several classes of the new exact solutions,with constant asymptotic values at infinity u|_(x^(2)+y^(2)→∞)→0,for the KK equation are constructed via the-dressing method. 展开更多
关键词 KK equation inverse scattering transform ■-dressing method exact solu-tion.
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Exact boundary controllability for the periodic higher-order KdV type equations
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作者 JIN Yanpeng FU Ying 《纯粹数学与应用数学》 2025年第3期413-421,共9页
In this paper,the exact boundary controllability of the higher-order KdVtype equation on torus is studied.That is,given the initial and final states in the appropriate space,by adding the appropriate control function ... In this paper,the exact boundary controllability of the higher-order KdVtype equation on torus is studied.That is,given the initial and final states in the appropriate space,by adding the appropriate control function on the boundary,the solution of the system can transition from the initial state to the specified final value.Firstly,we establish the observability inequality for the higher-order KdV-type equation by Ingham inequality.Then,based on the observability inequality,Hilbert uniqueness method and a integral identity we obtain the exact boundary controllability of the higher-order KdV-type equation. 展开更多
关键词 Higher-order KdV equation OBSERVABILITY exact boundary controllability
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