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rTMS Improves Cognitive Function and Brain Network Connectivity in Patients With Alzheimer’s Disease
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作者 XU Gui-Zhi LIU Lin +4 位作者 GUO Miao-Miao WANG Tian GAO Jiao-Jiao JI Yong WANG Pan 《生物化学与生物物理进展》 北大核心 2025年第8期2131-2145,共15页
Objective Repetitive transcranial magnetic stimulation(rTMS)has demonstrated efficacy in enhancing neurocognitive performance in Alzheimer’s disease(AD),but the neurobiological mechanisms linking synaptic pathology,n... Objective Repetitive transcranial magnetic stimulation(rTMS)has demonstrated efficacy in enhancing neurocognitive performance in Alzheimer’s disease(AD),but the neurobiological mechanisms linking synaptic pathology,neural oscillatory dynamics,and brain network reorganization remain unclear.This investigation seeks to systematically evaluate the therapeutic potential of rTMS as a non-invasive neuromodulatory intervention through a multimodal framework integrating clinical assessments,molecular profiling,and neurophysiological monitoring.Methods In this prospective double-blind trial,12 AD patients underwent a 14-day protocol of 20 Hz rTMS,with comprehensive multimodal assessments performed pre-and postintervention.Cognitive functioning was quantified using the mini-mental state examination(MMSE)and Montreal cognitive assessment(MOCA),while daily living capacities and neuropsychiatric profiles were respectively evaluated through the activities of daily living(ADL)scale and combined neuropsychiatric inventory(NPI)-Hamilton depression rating scale(HAMD).Peripheral blood biomarkers,specifically Aβ1-40 and phosphorylated tau(p-tau181),were analyzed to investigate the effects of rTMS on molecular metabolism.Spectral power analysis was employed to investigate rTMS-induced modulations of neural rhythms in AD patients,while brain network analyses incorporating topological properties were conducted to examine stimulus-driven network reorganization.Furthermore,systematic assessment of correlations between cognitive scale scores,blood biomarkers,and network characteristics was performed to elucidate cross-modal therapeutic associations.Results Clinically,MMSE and MOCA scores improved significantly(P<0.05).Biomarker showed that Aβ1-40 level increased(P<0.05),contrasting with p-tau181 reduction.Moreover,the levels of Aβ1-40 were positively correlated with MMSE and MOCA scores.Post-intervention analyses revealed significant modulations in oscillatory power,characterized by pronounced reductions in delta(P<0.05)and theta bands(P<0.05),while concurrent enhancements were observed in alpha,beta,and gamma band activities(all P<0.05).Network analysis revealed frequency-specific reorganization:clustering coefficients were significantly decreased in delta,theta,and alpha bands(P<0.05),while global efficiency improvement was exclusively detected in the delta band(P<0.05).The alpha band demonstrated concurrent increases in average nodal degree(P<0.05)and characteristic path length reduction(P<0.05).Further research findings indicate that the changes in the clinical scale HAMD scores before and after rTMS stimulation are negatively correlated with the changes in the blood biomarkers Aβ1-40 and p-tau181.Additionally,the changes in the clinical scales MMSE and MoCA scores were negatively correlated with the changes in the node degree of the alpha frequency band and negatively correlated with the clustering coefficient of the delta frequency band.However,the changes in MMSE scores are positively correlated with the changes in global efficiency of both the delta and alpha frequency bands.Conclusion 20 Hz rTMS targeting dorsolateral prefrontal cortex(DLPFC)significantly improves cognitive function and enhances the metabolic clearance ofβ-amyloid and tau proteins in AD patients.This neurotherapeutic effect is mechanistically associated with rTMS-mediated frequency-selective neuromodulation,which enhances the connectivity of oscillatory networks through improved neuronal synchronization and optimized topological organization of functional brain networks.These findings not only support the efficacy of rTMS as an adjunctive therapy for AD but also underscore the importance of employing multiple assessment methods—including clinical scales,blood biomarkers,and EEG——in understanding and monitoring the progression of AD.This research provides a significant theoretical foundation and empirical evidence for further exploration of rTMS applications in AD treatment. 展开更多
关键词 transcranial magnetic stimulation Alzheimer’s disease power spectral density ELECTROENCEPHALOGRAM brain functional network
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Impact of improved air quality on lung function and blood pressure of middle-aged and older population in China
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作者 Xiuling Zhao Andreas M.Neophytou 《Journal of Environmental Sciences》 2025年第9期846-857,共12页
Long-term exposure to fine particulate matters(PM_(2.5))has been associated with respiratory and cardiovascular diseases and the burden are potentially higher in China experiencing heavy air pollution.In this study,we... Long-term exposure to fine particulate matters(PM_(2.5))has been associated with respiratory and cardiovascular diseases and the burden are potentially higher in China experiencing heavy air pollution.In this study,we established the exposure-response association between long-term exposures to PM_(2.5)and lung function and blood pressure in Chinesemiddle-aged and older adults using linearmixed-effects and generalized additive mixedmodels based on 3 waves longitudinal health outcomes data by enrolling 19,988 participants from 121 cities across themainland of China.We also assessed the effect of Clean Air Policy(CAP)based on a quasi-experimental difference-in-differences(DID)design.A 10μg/m^(3)increase in PM_(2.5)concentration was associated with a 7.18(95%confidence interval[CI]:-8.35,-6.02)L/min decrease in PEF(peak expiratory flow)and a 0.72(95%[CI]:0.53,0.90)and a 0.30(95%[CI]:0.18,0.42)mmHg increase in systolic and diastolic blood pressure,respectively.The associations were more pronounced in males and rural areas for PEF,but similar across subgroups for blood pressure.DID results suggested that the effect of CAP on health outcomes were sensitive tomagnitudes of reduction in PM_(2.5).A 5μg/m^(3)reduction in PM_(2.5)or more generally led to 18.70(95%[CI]:0.79,36.61)higher PEF and-2.05(95%[CI]:-3.87,-0.23)lower diastolic blood pressure,respectively,compared to no reduction or increase in exposure.However,the effects were significant only in rural areas.Our analysis support CAP aiming to benefit public health and provides insights to inform future control policy for efficiently decreasing air pollution exposure burden. 展开更多
关键词 PM_(2.5) Lung function Blood pressure Clean Air policy Difference-in-difference model
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Normality and Shared Functions Wandering on the Sphere
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作者 Guangsheng WANG Fei LI Yan XU 《Journal of Mathematical Research with Applications》 2025年第3期329-336,共8页
In this paper,we obtain a normality criterion for families of meromorphic functions concerning‘wandering’shared functions,which generalizes and improves Montel’s criterion and the related results due to Schwick,Xu-... In this paper,we obtain a normality criterion for families of meromorphic functions concerning‘wandering’shared functions,which generalizes and improves Montel’s criterion and the related results due to Schwick,Xu-Fang,Xu-Qiu,and Grahl-Nevo.Also,a normality relationship between two families is given. 展开更多
关键词 meromorphic function normal family wandering shared function Montel’s criterion
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A Comparison of Pediatric Drug Policy and Development in China and the United States
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作者 Zhao Xinran Munire Mohetaer +2 位作者 Sun Xiaowen Wang Su Chen Yuwen 《Asian Journal of Social Pharmacy》 2025年第4期325-336,共12页
Objective To find the shortcomings of children’s drug research and development policy in China,and to put forward feasible suggestions for encouraging China’s children’s drug research and development by drawing the... Objective To find the shortcomings of children’s drug research and development policy in China,and to put forward feasible suggestions for encouraging China’s children’s drug research and development by drawing the experience from the United States.Methods To compare the similarities and differences between the policies guiding the use of children’s medicines issued by China and the United States.Results and Conclusion In recent years,the Chinese government has introduced a number of policies,but there is still a big gap in clinical trial design and drug review system compared with the policies of the United States.China should further improve the laws and regulations related to children’s medication,promote the development of clinical trials,develop pricing programs,and expand international cooperation,so as to formulate more scientific and comprehensive guiding principles for the research and development of children’s medication. 展开更多
关键词 children’s medication policies and regulations implementation effectiveness
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Point Defects and Grain Boundaries Effects on Electrical Transports of PbTe Using the Non‑equilibrium Green’s Function
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作者 Mi Qin Bingqing Cao +6 位作者 Pan Zhang Xuemei Zhang Ziqi Han Xiaohong Zheng Xianlong Wang Xin Chen Yongsheng Zhang 《Acta Metallurgica Sinica(English Letters)》 2025年第5期811-822,共12页
Defect engineering is a commonly methodology used to enhance the thermoelectric performance of thermoelectric PbTe by improving its electronic transport properties.At the nanoscale,defects can induce quantum tunneling... Defect engineering is a commonly methodology used to enhance the thermoelectric performance of thermoelectric PbTe by improving its electronic transport properties.At the nanoscale,defects can induce quantum tunneling effects that significantly impact the electrical properties of materials.To understand the specific mechanisms underlying the quantum transport properties of PbTe,we employ the non-equilibrium Green's function(NEGF)method to investigate the effects of intrinsic defects(point defects and grain boundaries)on the electronic transport properties of PbTe-based nanodevices from a quantum mechanical perspective.Our results show that the Pb vacancy(VPb)has the highest conduction.The conduction depends on the defect type,chemical potential and bias voltage.The presence of intrinsic point defects introduces impurity levels,facilitating the electron tunneling and leading to an increase in the transmission coefficient,thereby enhancing the electronic transport properties.For PbTe containing grain boundaries,these boundaries suppress the electronic transport properties.The Te occupied twin boundary(Te-TB)exerts a stronger inhibitory effect than the Pb occupied twin boundary(Pb-TB).Nevertheless,the combined effect between twin boundaries and point defects can enhance the electrical properties.Therefore,in order to obtain highly conductive of PbTe materials,a Te-rich synthesis environment should be used to promote the effective formation of Pb vacancy.Our work offers a comprehensive understanding of the impact of defects on electron scattering in thermoelectric materials. 展开更多
关键词 Thermoelectric material PBTE Non-equilibrium Green’s function TRANsMIssION DEFECTs
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The Impact of EU Immigration Law and Policy on Immigrants’Subjective Well-Being
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作者 Quan Cheng Yun Lin Hui Yu 《International Journal of Mental Health Promotion》 2025年第12期1961-1988,共28页
Background:Against the backdrop of the complex interplay between global migration flows and the European Union’s governance system,immigrants’subjective well-being(SWB)has become a crucial indicator for assessing bo... Background:Against the backdrop of the complex interplay between global migration flows and the European Union’s governance system,immigrants’subjective well-being(SWB)has become a crucial indicator for assessing both their social integration and the effectiveness of integration policies.However,few studies have systematically linked immigration law and policy to SWB through a structured framework of human needs.This study aims to assess how European Union(EU)immigration policies influence immigrants’SWB by facilitating the fulfillment of hierarchical needs based on Maslow’s theory.Methods:Using data from the European Social Survey(ESS,2010–2023),this study analyzed 28,854 first-generation and second-generation immigrants across 24 EU member states.This study employed hierarchical regression models to assess the relative contribution of five levels of needs-physiological,safety,social,esteem,and self-actualization-in predicting life satisfaction and happiness,controlling for sociodemographic factors.Results:Safety needs-comprising perceived safety and institutional trust-produced the largest model improvement(ΔR^(2)≈0.06–0.07).Physiological needs(stable income and self-rated health)also had significant positive effect(β=0.06–0.25,p<0.001).Social and esteem needs showed moderate associations(β≈0.09–0.17,p<0.001),while self-actualization needs(education and union membership)displayed generational variation(β=0.02–0.10,p<0.01).Conclusion:This study not only validates the applicability of Maslow’s theory in migration research but also empirically establishes a policy hierarchy:ensuring physiological and safety needs as a foundation,supporting social and esteem needs,and enabling self-actualization pathways are essential for enhancing immigrant well-being.The findings offer valuable theoretical insights and practical guidance for refining immigrant integration policies within the EU’s multi-level governance structure. 展开更多
关键词 subjective well-being immigration law and policy EU immigration Maslow’s hierarchy of needs
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Green’s Functions of a Class of Sturm-Liouville Problems with Eigenparameters in Boundary Conditions
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作者 XIAO Lu MU Dan ZHANG Ruifan 《数学理论与应用》 2025年第1期94-106,共13页
In this paper,we study a class of Sturm-Liouville problems,where the boundary conditions involve eigenparameters.Firstly,by defining a new inner product which depends on the transmission conditions,we obtain a new Hil... In this paper,we study a class of Sturm-Liouville problems,where the boundary conditions involve eigenparameters.Firstly,by defining a new inner product which depends on the transmission conditions,we obtain a new Hilbert space,on which the concerned operator A is self-adjoint.Then we construct the fundamental solutions to the problem,obtain the necessary and sufficient conditions for eigenvalues,and prove that the eigenvalues are simple.Finally,we investigate Green’s functions of such problem. 展开更多
关键词 sturm-Liouville problem Eigenparameter-dependent boundary condition Green’s function
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Analyzing point liquid loading effects on transversely isotropic poroelastic media using Green's function
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作者 Muzammal Hameed Tariq Yue-Ting Zhou 《Communications in Theoretical Physics》 2025年第8期1-10,共10页
Understanding the effects of point liquid loading on transversely isotropic poroelastic media is crucial for advancing geomechanics and biomechanics, where precise modeling of fluid-structure interactions is essential... Understanding the effects of point liquid loading on transversely isotropic poroelastic media is crucial for advancing geomechanics and biomechanics, where precise modeling of fluid-structure interactions is essential. This paper presents a comprehensive analysis of infinite transversely isotropic poroelasticity under a fluid source, based on Biot's theory, aiming to uncover new and previously unexplored insights in the literature. We begin our study by deriving a general solution for fluid-saturated, transversely isotropic poroelastic materials in terms of harmonic functions that satisfy sixth-order homogeneous partial differential equations, using potential theory and Almansi's theorem. Based on these general solutions and potential functions, we construct a Green's function for a point fluid source, introducing three new harmonic functions with undetermined constants. These constants are determined by enforcing continuity and equilibrium conditions. Substituting these into the general solution yields fundamental solutions for poroelasticity that provide crucial support for a wide range of project problems. Numerical results and comparisons with existing literature are provided to illustrate physical mechanisms through contour plots. Our observations reveal that all components tend to zero in the far field and become singular at the concentrated source. Additionally, the contours exhibit rapid changes near the point fluid source but display gradual variations at a distance from it. These findings highlight the intricate behavior of the system under point liquid loading, offering valuable insights for further research and practical applications. 展开更多
关键词 poroelasticity one-point loading Green’s functions transversely isotropic materials potential theory method
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Functionally graded materials based on porous poly(ionic liquid)s:Design strategies and applications
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作者 Xiao-Yu Han Si-Hua Liu +1 位作者 Su-Yun Zhang Jian-Ke Sun 《Chinese Journal of Structural Chemistry》 2025年第7期86-102,共17页
Functionally graded materials (FGMs) are innovative materials distinguished by gradual variations in composition and structure, offering exceptional properties for diverse applications. Poly(ionic liquid)s (PILs), mer... Functionally graded materials (FGMs) are innovative materials distinguished by gradual variations in composition and structure, offering exceptional properties for diverse applications. Poly(ionic liquid)s (PILs), merging the characteristics of polymers and ionic liquids, have emerged as viable options for the development of FGMs given their tunable skeleton, ionic conductivity, and compatibility with various functional materials. This review highlights the latest advancements in the design strategies of FGMs based on porous PILs, focusing on single and multi-gradient structures. Furthermore, we also highlight their emerging applications in molecular recognition, sensing, adsorption, separation, and catalysis. By exploring the interplay between porosity, ionic functionality, and gradient architecture, this review offers perspectives on the prospects of PIL-based FGMs for tackling global challenges in energy, environment, and healthcare. 展开更多
关键词 functionally graded materials Poly(ionic liquid)s Membranes Bio-inspired materials sENsING
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Trump 2.0’s Policy Toward Africa Under the“America First”Doctrine
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作者 Wang Xuejun 《Contemporary World》 2025年第5期46-52,共7页
Since the end of the Cold War,the core goal of U.S.policy toward Africa has been to build its influence on the continent through development assistance and trade preferences attached with political conditionalities,de... Since the end of the Cold War,the core goal of U.S.policy toward Africa has been to build its influence on the continent through development assistance and trade preferences attached with political conditionalities,defined as“assistance for concessions”.After the September 11 attacks,counterterrorism became a priority in U.S.national security strategy,being one of the three pillars of U.S.policy toward Africa alongside assistance and trade. 展开更多
关键词 trump development assistance america first trade preferences attached political conditionalitiesdefined africa u s policy trade preferences build its influence continent
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Constructive Strategy of Amine Functionalization on Cu−In−Zn−S With N→Cu Coordination for Efficacious Photocatalytic Hydrogen Evolution
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作者 Mengmeng Ma Runkang Lin +4 位作者 Kaige Huang Shizhong Yue Maohong Fan Zhijie Wang Shengchun Qu 《Carbon Energy》 2025年第10期162-173,共12页
Functionalization has emerged as a pivotal endeavor to tailor the surface properties of photocatalysts.We propose a facile amine functionalization strategy to establish a Cu−In−Zn−S(CIZS)/NiSx hybrid with covalent bon... Functionalization has emerged as a pivotal endeavor to tailor the surface properties of photocatalysts.We propose a facile amine functionalization strategy to establish a Cu−In−Zn−S(CIZS)/NiSx hybrid with covalent bonds using individual ethylenediamine(EDA)molecules.Our approach witnesses a remarkable photocatalytic hydrogen evolution(PHE)competence of 65.93 mmol g^(−1)h^(−1)driven by visible light,the highest value yielded by CIZS to date.X-ray absorption spectra of CIZS and density functional theory(DFT)calculations confirm the crucial amine N→Cu coordination after amine functionalization.The new emerging coordination via lone-pair electron donation profitably accesses the regulation of the coordination environment,electronic structures,and carrier behavior.Moreover,individual EDA molecule with two-terminal−NH2 group serves as a molecular bridge to hybrid CIZS and NiS_(x)cocatalyst via N→Cu and N→Ni coordination,favorably promoting efficient charge transport.This study provides advances in practical functionalizing photocatalysts. 展开更多
关键词 amine functionalization COORDINATION Cu−In−Zn−s molecular bridges photocatalytic hydrogen evolution
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Numerical simulation of the fluid and flexible rods interaction using a semi-resolved coupling model promoted by anisotropic Gaussian kernel function
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作者 Caiping Jin Jingxin Zhang Yonglin Sun 《Theoretical & Applied Mechanics Letters》 2025年第1期5-8,共4页
The numerical simulation of the fluid flow and the flexible rod(s)interaction is more complicated and has lower efficiency due to the high computational cost.In this paper,a semi-resolved model coupling the computatio... The numerical simulation of the fluid flow and the flexible rod(s)interaction is more complicated and has lower efficiency due to the high computational cost.In this paper,a semi-resolved model coupling the computational fluid dynamics and the flexible rod dynamics is proposed using a two-way domain expansion method.The gov-erning equations of the flexible rod dynamics are discretized and solved by the finite element method,and the fluid flow is simulated by the finite volume method.The interaction between fluids and solid rods is modeled by introducing body force terms into the momentum equations.Referred to the traditional semi-resolved numerical model,an anisotropic Gaussian kernel function method is proposed to specify the interactive forces between flu-ids and solid bodies for non-circle rod cross-sections.A benchmark of the flow passing around a single flexible plate with a rectangular cross-section is used to validate the algorithm.Focused on the engineering applications,a test case of a finite patch of cylinders is implemented to validate the accuracy and efficiency of the coupled model. 展开更多
关键词 semi-resolved coupling model Two-way domain expansion method Anisotropic Gaussian kernel function Flexible rod(s)
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A Brief Analysis of the Impact of China’s Monetary Policy on Natural Gas Prices
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作者 Zhang Longxing 《China Oil & Gas》 2025年第3期49-53,共5页
We often hear statements like“the market raises expectations for central bank interest rate cuts,resulting in higher commodity prices”.Given the current situation,the People’s Bank of China might adopt a more accom... We often hear statements like“the market raises expectations for central bank interest rate cuts,resulting in higher commodity prices”.Given the current situation,the People’s Bank of China might adopt a more accommodative monetary policy to mitigate the impact of the China-U.S.trade friction.Will this further easing of the monetary environment lead to an increase in natural gas prices? 展开更多
关键词 natural gas natural gas prices China U s trade friction central bank interest rate cuts central bank interest rate commodity prices given easing monetary environment monetary policy
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Industrial Policy Analysis of Restricted Development Zones in Western China——A Study of State-level Main Producing Areas of Agricultural Products and Key Ecological Functional Areas
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作者 Chen Ying 《Contemporary Social Sciences》 2016年第2期74-85,共12页
As one of the important policies of promoting the formation of main functional areas, the industrial policy directly determines the sustainable growth of space control ability of main functional areas. A restricted de... As one of the important policies of promoting the formation of main functional areas, the industrial policy directly determines the sustainable growth of space control ability of main functional areas. A restricted development zone is a type of main functional area which provides agricultural products and ecological products, assures the supply of national agricultural products and the stability of ecosystems, as well as safeguards the ecological functions and agricultural functions of wider regions by restricting its own development. Therefore scientific, complete and operable industrial policy support is needed. Restricted development zones are distributed widely in western China. With the restriction of their main functions, differential industrial policies should be implemented in the development of the restricted development zones: Dealing well with the relationship between industrial development and ecological protection, developing special industries which are friendly to resources and environment and appropriate for local conditions, guiding and encouraging industries to learn from regions with favorable development conditions, orderly withdrawing industries and enterprises adverse to main functions, facilitating industrial structure upgrading, optimizing industrial organization, improving industrial technological level and rationalizing industrial layout. 展开更多
关键词 Western China REsTRICTED development main producing areas of agricultural products KEY ECOLOGICAL functional areas INDUsTRIAL policies
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S型功能梯度复合梁的非线性颤振特性分析
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作者 汪卫东 韩明君 冯瑞龙 《首都师范大学学报(自然科学版)》 2026年第1期33-43,55,共12页
针对飞行器超音速飞行时可能发生的颤振等力学行为,基于经典梁理论和一阶活塞气动理论,探究S型功能梯度复合梁的非线性颤振特性。考虑2类S型功能梯度材料(S-FGM)复合梁结构,采用Galerkin法对系统控制方程进行离散化处理,结合Routh-Hurw... 针对飞行器超音速飞行时可能发生的颤振等力学行为,基于经典梁理论和一阶活塞气动理论,探究S型功能梯度复合梁的非线性颤振特性。考虑2类S型功能梯度材料(S-FGM)复合梁结构,采用Galerkin法对系统控制方程进行离散化处理,结合Routh-Hurwitz稳定性判据与Hopf分岔理论,进一步推导出系统发生颤振时对应的临界流速与频率的解析表达式。通过数值算例,对比了2类不同分布复合梁在超音速环境下的稳定性,并系统地研究了梯度指数等关键物理参变量对S型功能梯度梁的颤振稳定性的影响,通过Runge-Kutta法对系统的稳定性进行验证。结果表明,随着功能梯度指数越大,系统将越容易发生颤振,研究结果将为S型功能梯度复合梁的设计优化提供理论依据。 展开更多
关键词 s型功能梯度 HOPF分岔 复合梁 颤振
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基于马尔科夫转换场与深度确定性策略梯度算法的VSC-HVDC系统控制参数优化方法
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作者 朱介北 黄闽杰 +3 位作者 俞露杰 欧开健 刘晓龙 贾宏杰 《中国电机工程学报》 北大核心 2026年第5期1821-1832,I0008,共13页
针对柔性直流输电系统(voltage source converter based high voltage direct current transmission,VSC-HVDC)控制参数设计过程中存在的鲁棒性差、依赖已知电路参数、工程设计经验化等问题,提出一种基于马尔科夫转换场(Markov transiti... 针对柔性直流输电系统(voltage source converter based high voltage direct current transmission,VSC-HVDC)控制参数设计过程中存在的鲁棒性差、依赖已知电路参数、工程设计经验化等问题,提出一种基于马尔科夫转换场(Markov transition field,MTF)与深度确定性策略梯度算法(deep deterministic policy gradient,DDPG)结合的鲁棒性强、不依赖电路参数特性以及可视化的VSC-HVDC控制参数优化设计方法。首先,采用马尔科夫转换场将电路功率、电压等一维时序波形数据转换为二维马尔科夫转换场域图像并使用马尔科夫转换场损失函数(Markov transition field loss,MTFL)判断二维转换域图的数据波动性;其次,将MTFL损失函数与DDPG算法相结合,综合利用MTFL损失函数对系统输出时序数据动态特性评价能力更强的优点和DDPG算法泛化性能优秀的特点,实现VSC-HVDC系统控制参数优化;最后,通过MATLAB模拟和实验结果验证该方法的有效性。 展开更多
关键词 柔性直流输电 控制参数优化 马尔科夫转换场损失函数 马尔科夫转换场 深度确定性策略梯度算法
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基于CT参数构建Fisher判别函数模型对胸腺瘤与前纵隔囊肿进行鉴别诊断的研究
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作者 杨宇琦 王思聪 +2 位作者 卢礼卿 张春芳 程远大 《中国临床新医学》 2026年第2期214-219,共6页
目的 探讨基于CT参数建立的Fisher判别函数模型对胸腺瘤与前纵隔囊肿进行鉴别诊断的价值。方法 回顾性收集2015年1月至2025年6月在中南大学湘雅医院胸外科经手术切除后病理检查证实为前纵隔囊肿(含胸腺囊肿和支气管囊肿)或胸腺瘤患者的... 目的 探讨基于CT参数建立的Fisher判别函数模型对胸腺瘤与前纵隔囊肿进行鉴别诊断的价值。方法 回顾性收集2015年1月至2025年6月在中南大学湘雅医院胸外科经手术切除后病理检查证实为前纵隔囊肿(含胸腺囊肿和支气管囊肿)或胸腺瘤患者的临床病理资料,计算肿瘤平扫和增强CT值与主动脉CT值的比值,采用单因素方差分析结合Bonferroni校正进行组间比较,基于筛得CT参数建立Fisher判别函数并对其进行验证。结果 共236例患者纳入研究,其中胸腺瘤组159例、胸腺囊肿组54例、支气管囊肿组23例。三组年龄比较差异无统计学意义(P > 0.05)。与胸腺瘤组和胸腺囊肿组相比,支气管囊肿组患者女性人数比例更高(P<0.001),肿瘤最大径更小(P<0.001)。胸腺瘤组中肿瘤呈分叶状的占比显著高于胸腺囊肿组和支气管囊肿组(P<0.001),脂肪间隙清晰率显著低于胸腺囊肿组和支气管囊肿组(P<0.001)。胸腺瘤组和支气管囊肿组的平扫CT值、平扫主动脉CT比值、增强CT值及增强主动脉CT比值均显著高于胸腺囊肿组(P<0.001),其中支气管囊肿组增强CT值、增强主动脉CT比值显著低于胸腺瘤组(P<0.001)。胸腺囊肿组和支气管囊肿组的CT强化值显著低于胸腺瘤组(P<0.001)。构建Fisher判别函数:D1=0.245×性别(0=女性,1=男性)+0.782×肿瘤形状(1=无分叶状,2=分叶状)+0.644×脂肪间隙(0=模糊,1=清晰)-0.344×增强CT值+97.228×增强主动脉CT比值+0.059×CT强化值-9.357;D2=0.970×性别(0=女性,1=男性)+0.583×肿瘤形状(1=无分叶状,2=分叶状)+0.903×脂肪间隙(0=模糊,1=清晰)-0.094×增强CT值+4.749×增强主动脉CT比值+0.110×CT强化值+0.546。交叉验证结果显示,该模型鉴别诊断胸腺瘤与前纵隔囊肿的总体符合率为95.76%。结论 基于CT参数建立的判别函数诊断模型在鉴别胸腺瘤与前纵隔囊肿中具有较高的诊断价值。 展开更多
关键词 胸腺瘤 前纵隔囊肿 胸腺囊肿 支气管囊肿 CT值 鉴别诊断 Fisher判别函数模型
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MATLAB/Simulink S-function在三相异步电机教学中的应用研究 被引量:5
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作者 巫庆辉 崔总泽 李琳 《渤海大学学报(自然科学版)》 CAS 2011年第3期249-253,共5页
针对三相异步电动机教学过程中较深的理论知识不利于学生理解与掌握的问题,对MATLAB/Simulink S-function在三相异步电机教学进行了应用研究,MATLAB环境下Simulink与S-function有机结合搭建了三相异步电动机的仿真平台,仿真结果验证了... 针对三相异步电动机教学过程中较深的理论知识不利于学生理解与掌握的问题,对MATLAB/Simulink S-function在三相异步电机教学进行了应用研究,MATLAB环境下Simulink与S-function有机结合搭建了三相异步电动机的仿真平台,仿真结果验证了该方法的有效性。 展开更多
关键词 教学 MATLAB/sIMULINK sfunction 电机与拖动 三相异步电动机
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Singularity-free Green's function for EM sources embedded in a stratified medium 被引量:3
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作者 翁爱华 刘云鹤 +1 位作者 殷长春 贾定宇 《Applied Geophysics》 SCIE CSCD 2016年第1期25-36,217,218,共14页
We present a method to unify the calculation of Green's functions for an electromagnetic(EM) transmitting source embedded in a homogeneous stratified medium.A virtual interface parallel to layer interfaces is intro... We present a method to unify the calculation of Green's functions for an electromagnetic(EM) transmitting source embedded in a homogeneous stratified medium.A virtual interface parallel to layer interfaces is introduced through the source location.The potentials for Green's function are derived by decomposing the partial wave solutions to Helmholtz's equations into upward and downward within boundaries.The amplitudes of the potentials in each stratum are obtained recursively from the initial amplitudes at the source level.The initial amplitudes are derived by coupling with the transmitting sources and following the discontinuity of the tangential electric and magnetic fields at the source interface.Only the initial terms are related to the transmitting sources and thus need to be modified for different transmitters,whereas the kernel connected with the stratified media stays unchanged.Hence,the present method can be easily applied to EM transmitting sources with little modification.The application of the proposed method to the marine controlled-source electromagnetic method(MCSEM) demonstrates its simplicity and flexibility. 展开更多
关键词 EM Marine EM Green's function stratified medium sINGULARITY
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Advances in the Regulation of RpoS Protein Expression and Its Function in Bacteria 被引量:2
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作者 王淑娴 李天保 +4 位作者 叶海斌 魏鉴腾 王勇强 刁菁 杨秀生 《Agricultural Science & Technology》 CAS 2012年第6期1215-1221,1225,共8页
RpoS protein is a σ factor of RNA polymerase that can control the expression of a group-specific gene, thus playing a vital role in bacteria. In bacteria, RpoS expression is under strict control and is mainly regulat... RpoS protein is a σ factor of RNA polymerase that can control the expression of a group-specific gene, thus playing a vital role in bacteria. In bacteria, RpoS expression is under strict control and is mainly regulated at three levels: transcription level, translation level and post-translational level. Environmental stress enters bacterial cells through signal transduction and leads to a series of variations in microenvironment, thereby causing changes of regulator and controlling its levels based on the direct and indirect interaction between regulator and RpoS protein. In addition, RpoS protein has played special roles in bacteria, therefore the changes of RpoS protein levels will lead to variations in expression levels of a large number of genes, thereby causing variations of bacterial response to different environmental stress and changes of certain characteristics of bacteria, which provides a new strategy for the control of bacterial diseases in the future. This paper reviewed the recent progress on the regulation of RpoS protein expression and its function in several common bacteria. Due to the functional complexity of RpoS protein, there are still a lot of unknown functions to be further identified. 展开更多
关键词 Rpos or σ s rpos gene Expression regulation Environmental stress Rpos function
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