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Equivariant Normal Forms for Parameterized Delay Differential Equations with Applications to Bifurcation Theory

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Acta Mathematica Sinica,English Series 2012年第4期28卷 825-856页

作者： shang jiang guo Yu Ming CHEN Jian Hong WU College of Mathematics and Econometrics Hu'nan University Department of Mathematics Wilfrid Laurier University Department of Mathematics and Statistics York University

In this paper, we develop an efficient approach to compute the equivariant normal form of delay differential equations with parameters in the presence of symmetry. We present and justify a process that involves center manifold reduction and normalization preserving the symmetry, and that yields normal forms explicitly in terms of the coefficients of the original system. We observe that the form of the reduced vector field relies only on the information of the linearized system at the critical point and on the inherent symmetry, and the normal forms give critical information about not only the existence but also the stability and direction of bifurcated spatiotemporal patterns. We illustrate our general results by some applications to fold bifurcation, equivariant Hopf bifurcation and Hopf-Hopf interaction, with a detailed case study of additive neurons with delayed feedback.

关键词： Equivariant delay differential equation normal form equilibrium stability bifurcation

C-X-C chemokine receptor type 5+CD8+T cells as immune regulators in hepatitis Be antigen-positive chronic hepatitis B under interferonalpha treatment

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World Journal of Gastroenterology 2025年第3期31卷 73-83页

作者： Zhen-Yu Xu Zhong-shang Dai guo-Zhong Gong Min Zhang Department of Infectious Diseases Second Xiangya HospitalCentral South UniversityChangsha 410011Hunan ProvinceChina Institute of Hepatology and Department of Infectious Diseases The Second Xiangya HospitalCentral South UniversityChangsha 410011Hunan ProvinceChina

BACKGROUND C-X-C chemokine receptor type 5(CXCR5)+CD8+T cells represent a unique immune subset with dual roles,functioning as cytotoxic cells in persistent viral infections while promoting B cell *** their importance,the specific role of CXCR5+CD8+T cells in chronic hepatitis B(CHB),particularly during interferon-alpha(IFN-α)treatment,is not fully *** study aims to elucidate the relationship between CXCR5+CD8+T cells and sustained serologic response(SR)in patients undergoing 48 weeks of pegylated IFN-α(peg-IFN-α)treatment for *** To elucidate the relationship between CXCR5+CD8+T cells and sustained SR in patients undergoing 48 weeks of peg-IFN-αtreatment for *** This study enrolled 60 patients with hepatitis Be antigen(HBeAg)-positive CHB undergoing 48 weeks of peg-IFN-α*** were assessed for eligibility based on criteria such as persistent HBsAg-positive status for at least six months,HBeAb-negative,hepatitis B virus DNA levels exceeding 2×104 copies/mL,and alanine aminotransferase(ALT)levels between 2 and 10 times the upper limit of *** samples were collected at baseline and at weeks 12,24,48,and a 24-week treatment-free follow-up(week 72)to measure serum interleukin(IL)-21 concentration via ELISA and to analyze CXCR5 and programmed death-ligand 1(PD-L1)expression on CD8+T cells by flow cytometry,CXCR5 is a chemokine receptor that directs immune cells to specific tissues,while PD-L1 is a protein that regulates immune responses by inhibiting T cell *** Patients with CHB exhibited significantly lower levels of circulating CXCR5+CD8+T cells compared to healthy controls(P<0.01).Notably,CXCR5+CD8+T cells were prominently expressed in patients who achieved sustained SR compared to non-SR(NSR).A significant correlation was observed between CXCR5 and PD-L1 expression(r=-0.189,P=0.002).However,there was no significant correlation between serum IL-21 levels and CXCR5+CD8+lymphocytes(r=-0.03,P=0.62

关键词： C-X-C chemokine receptor type 5 Programmed death-ligand 1 Interleukin-21 Pegylated interferon-alpha Chronic hepatitis B

一种80℃固化环氧树脂体系的非等温固化动力学

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宇航材料工艺 2017年第3期47卷 19-24页

作者：樊孟金周宇尚呈元蒋文革郭鸿俊航天材料及工艺研究所北京100076

采用非等温DSC研究了80℃固化环氧树脂体系LTCEP的非等温固化行为。采用GaussianLorentzian加和模型对DSC曲线进行分峰处理,采用Flynn-Wall-Ozawa法确定不同阶段反应的活化能随转化率的变化情况。然后采用Málek方法研究不同阶段反应的... 详细信息

采用非等温DSC研究了80℃固化环氧树脂体系LTCEP的非等温固化行为。采用GaussianLorentzian加和模型对DSC曲线进行分峰处理,采用Flynn-Wall-Ozawa法确定不同阶段反应的活化能随转化率的变化情况。然后采用Málek方法研究不同阶段反应的非等温固化动力学,得到树脂体系总的反应速率方程并预测树脂体系在不同温度下的固化行为。最后采用拉伸测试表征了LTCEP体系的力学性能。非等温DSC结果表明该树脂体系的DSC曲线可用三个独立的放热峰进行叠加来拟合;三个阶段反应活化能随转化率的变化均不明显,其活化能平均值分别为85.98、84.85和87.16 k J/mol;Sesták-Berggren模型可很好地描述该树脂体系在不同阶段的固化行为。预测LTCEP在150℃下3 min、140℃下5.5 min即可达到90%转化率。拉伸测试结果表明LTCEP经80℃固化后拉伸强度和断裂伸长率分别为(51.34±11.78)MPa和(1.23±0.34)%,125℃后处理对拉伸性能影响不大。

关键词：环氧树脂 80℃固化固化动力学 DSC

Ultra‑High Sensitivity Anisotropic Piezoelectric Sensors for Structural Health Monitoring and Robotic Perception

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Nano-Micro Letters 2025年第2期17卷 432-446页

作者： Hao Yin Yanting Li Zhiying Tian Qichao Li Chenhui jiang Enfu Liang Yiping guo State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Beijing Vacuum Electronics Research Institute Beijing 100015People’s Republic of China Fundamental Science On Vibration Shock and Noise LaboratoryState Key Laboratory of Mechanical System and VibrationSchool of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Monitoring minuscule mechanical signals,both in magnitude and direction,is imperative in many application scenarios,e.g.,structural health monitoring and robotic sensing ***,the piezoelectric sensor struggles to satisfy the requirements for directional recognition due to the limited piezoelectric coefficient matrix,and achieving sensitivity for detecting micrometer-scale deformations is also ***,we develop a vector sensor composed of lead zirconate titanate-electronic grade glass fiber composite filaments with oriented arrangement,capable of detecting minute anisotropic *** as-prepared vector sensor can identify the deformation directions even when subjected to an unprecedented nominal strain of 0.06%,thereby enabling its utility in accurately discerning the 5μm-height wrinkles in thin films and in monitoring human pulse *** ultra-high sensitivity is attributed to the formation of porous ferroelectret and the efficient load transfer efficiency of continuous lead zirconate titanate ***,when integrated with machine learning techniques,the sensor’s capability to recognize multi-signals enables it to differentiate between 10 types of fine textures with 100%*** structural design in piezoelectric devices enables a more comprehensive perception of mechanical stimuli,offering a novel perspective for enhancing recognition accuracy.

关键词： Flexible piezoelectric filaments Anisotropic Ultra-high sensitivity Structural health detection Texture recognition

Prediction and stratification for the surgical adverse events after minimally invasive esophagectomy:A two-center retrospective study

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World Journal of Gastroenterology 2025年第3期31卷 50-61页

作者： Qi-Hong Zhong jiang-Shan Huang Fei-Long guo Jing-Yu Wu Mao-Xiu Yuan Jia-Fu Zhu Wen-Wei Lin Sui Chen Zhen-Yang Zhang jiang-Bo Lin Department of Thoracic Surgery Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina The Graduate School Fujian Medical UniversityFuzhou 350001Fujian ProvinceChina Department of Thoracic Surgery Affiliated Hospital of Jinggangshan UniversityJi’an 343000Jiangxi ProvinceChina

BACKGROUND Minimally invasive esophagectomy(MIE)is a widely accepted treatment for esophageal cancer,yet it is associated with a significant risk of surgical adverse events(SAEs),which can compromise patient recovery and long-term *** preoperative identification of high-risk patients is critical for improving *** To establish and validate a risk prediction and stratification model for the risk of SAEs in patients with *** This retrospective study included 747 patients who underwent MIE at two centers from January 2019 to February *** were separated into a train set(n=549)and a validation set(n=198).After screening by least absolute shrinkage and selection operator regression,multivariate logistic regression analyzed clinical and intraoperative variables to identify independent risk factors for SAEs.A risk stratification model was constructed and validated to predict the probability of *** SAEs occurred in 10.2%of patients in train set and 13.6%in the validation *** with SAE had significantly higher complication rate and a longer hospital stay after *** key independent risk factors identified included chronic obstructive pulmonary disease,a history of alcohol consumption,low forced expiratory volume in the first second,and low albumin *** stratification model has excellent prediction accuracy,with an area under the curve of 0.889 for the training set and an area under the curve of 0.793 for the validation *** The developed risk stratification model effectively predicts the risk of SAEs in patients undergoing MIE,facilitating targeted preoperative interventions and improving perioperative management.

关键词： Surgical adverse events Minimally invasive esophagectomy Esophageal cancer Stratification model Perioperative management

Reduced mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor contributes to neurodegeneration in a model of spinal and bulbar muscular atrophy pathology

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Neural Regeneration Research 2025年第9期20卷 2655-2666页

作者： Yiyang Qin Wenzhen Zhu Tingting guo Yiran Zhang Tingting Xing Peng Yin Shihua Li Xiao-jiang Li Su Yang Guangdong Key Laboratory of Non-human Primate Research Key Laboratory of CNS Regeneration(Ministry of Education)Guangdong–HongKong–Macao Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong ProvinceChina

Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto *** mutant androgen receptor protein,characterized by polyglutamine expansion,is prone to misfolding and forms aggregates in both the nucleus and cytoplasm in the brain in spinal and bulbar muscular atrophy *** aggregates alter protein-protein interactions and compromise transcriptional *** this study,we reported that in both cultured N2a cells and mouse brain,mutant androgen receptor with polyglutamine expansion causes reduced expression of mesencephalic astrocyte-de rived neurotrophic *** n of mesencephalic astrocyte-derived neurotrophic factor amelio rated the neurotoxicity of mutant androgen receptor through the inhibition of mutant androgen receptor *** down endogenous mesencephalic astrocyte-derived neurotrophic factor in the mouse brain exacerbated neuronal damage and mutant androgen receptor *** findings suggest that inhibition of mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor is a potential mechanism underlying neurodegeneration in spinal and bulbar muscular atrophy.

关键词： androgen receptor mesencephalic astrocyte-derived neurotrophic factor mouse model neurodegeneration neuronal loss neurotrophic factor polyglutamine disease protein misfolding spinal and bulbar muscular atrophy transcription factor

Effects of carbon content on the microstructure and tensile properties of a low-density steel

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International Journal of Minerals,Metallurgy and Materials 2025年第02期 391-401页

作者： Yongxuan shang Mingyu Fan Shuyong jiang Zhongwu Zhang Key Laboratory of Superlight Materials and Surface Technology Ministry of Education College of Materials Science and Chemical Engineering Harbin Engineering University State Key Laboratory of Metal Material for Marine Equipment and Application Iron & Steel Research Institute of Ansteel Group Corporation

Carbon can change the phase components of low-density steels and influence the mechanical properties. In this study, a new method to control the carbon content and avoid the formation of δ-ferrite by decarburization treatment was proposed. The microstructural changes and mechanical characteristics with carbon content induced by decarburization were systematically examined. Crussard–Jaoul(C–J) analysis was employed to examine the work hardening characteristics during the tensile test. During decarburization by heat treatments, the carbon content within the austenite phase decreased, while Mn and Al were almost unchanged; this made the steel with full austenite transform into the austenite and ferrite dual phase. Meanwhile,(Ti,V)C carbides existed in both matrix phase and the mole fraction almost the same. In addition, the formation of other carbides restrained. Carbon loss induced a decrease in strength due to the weakening of the carbon solid solution. For the steel with the single austinite, the deformation mode of austenite was the dislocation planar glide, resulting in the formation of microbands. For the dual-phase steel, the deformation occurred by the dislocation planar glide of austenite first, with the increase in strain, the cross slip of ferrite took place, forming dislocation cells in ferrite. At the late stage of deformation, the work hardening of austinite increased rapidly, while that of ferrite increased slightly.

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Loss-of-function mutations of microRNA-142-3p promote ASH1L expression to induce immune evasion and hepatocellular carcinoma progression

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World Journal of Gastroenterology 2025年第1期31卷 126-145页

作者： Xing-Hui Yu Yan Xie Jian Yu Kun-Ning Zhang Zhou-Bo guo Di Wang Zhao-Xian Li Wei-Qi Zhang Yu-Ying Tan Li Zhang Wen-Tao jiang School of Medicine Nankai UniversityTianjin 300192China Tianjin Key Laboratory of Molecular Diagnosis and Treatment of Liver Cancer Tianjin First Center HospitalTianjin 300192China Department of Liver Transplantation Tianjin First Center HospitalTianjin 300192China First Central Clinical School Tianjin Medical UniversityTianjin 300192China

BACKGROUND Hepatocellular carcinoma(HCC)has been a pervasive malignancy throughout the world with elevated *** therapeutic targets are beneficial to treat and predict the ***,the exact molecular mechanisms leading to the progression of HCC are still *** has shown that the microRNA-142-3p level decreases in HCC,whereas bioinformatics analysis of the cancer genome atlas database shows the ASH1L expression increased among liver tumor *** this paper,we will explore the effects and mechanisms of microRNA-142-3p and ASH1L affect the prognosis of HCC patients and HCC cell bioactivity,and the association between *** To investigate the effects and mechanisms of microRNA-142-3p and ASH1L on the HCC cell bioactivity and prognosis of HCC *** In this study,we grouped HCC patients according to their immunohistochemistry results of ASH1L with pathological tissues,and retrospectively analyzed the prognosis of HCC ***,explored the roles and mechanisms of microRNA-142-3p and ASH1L by cellular and animal experiments,which involved the following experimental methods:Immunohistochemical staining,western blot,quantitative real-time-polymerase chain reaction,flow cytometric analysis,tumor xenografts in nude mice,*** statistical methods involved in this study contained t-test,one-way analysis of variance,theχ^(2)test,the Kaplan-Meier approach and the log-rank *** In this study,we found that HCC patients with high expression of ASH1L possess a more recurrence rate as well as a decreased overall survival ***1L promotes the tumorigenicity of HCC and microRNA-142-3p exhibits reduced expression in HCC tissues and interacts with ASH1L through targeting the ASH1L 3′untranslated ***,microRNA-142-3p promotes apoptosis and inhibits proliferation,invasion,and migration of HCC cell lines in vitro via *** the exploration mechanism,we found ASH1L may promote an immunosuppressive mi

关键词： Hepatocellular carcinoma MicroRNA-142-3p ASH1L Immune evasion Tumor immune microenvironment Apoptosis

Unraveling the significance of cobalt on transformation kinetics, crystallography and impact toughness in high-strength steels

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International Journal of Minerals,Metallurgy and Materials 2025年第02期 380-390页

作者： Yishuang Yu Jingxiao Zhao Xuelin Wang Hui guo Zhenjia Xie Chengjia shang Collaborative Innovation Center of Steel Technology University of Science and Technology Beijing School of Materials Science and Engineering Shanghai Jiao Tong University State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

This work reveals the significant effects of cobalt(Co) on the microstructure and impact toughness of as-quenched highstrength steels by experimental characterizations and thermo-kinetic analyses. The results show that the Co-bearing steel exhibits finer blocks and a lower ductile–brittle transition temperature than the steel without Co. Moreover, the Co-bearing steel reveals higher transformation rates at the intermediate stage with bainite volume fraction ranging from around 0.1 to 0.6. The improved impact toughness of the Co-bearing steel results from the higher dense block boundaries dominated by the V1/V2 variant pair. Furthermore, the addition of Co induces a larger transformation driving force and a lower bainite start temperature(BS), thereby contributing to the refinement of blocks and the increase of the V1/V2 variant pair. These findings would be instructive for the composition, microstructure design, and property optimization of high-strength steels.

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