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Constant Barrier Strategies in a Two-state Markov-modulated Dual Risk Model

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Acta Mathematicae Applicatae Sinica 2011年第4期27卷 679-690页

作者： Xue-min MA Kui LUO Guang-ming wang yi-jun hu School of Mathematics and Statistics Wuhan University Wuhan 430072 China

In this paper, we consider the dividend problem in a two-state Markov-modulated dual risk model, in which the gain arrivals, gain sizes and expenses are influenced by a Markov process. A system of integro-differential equations for the expected value of the discounted dividends until ruin is derived. In the case of exponential gain sizes, the equations are solved and the best barrier is obtained via numerical example. Finally, using numerical example, we compare the best barrier and the expected discounted dividends in the two-state Markov-modulated dual risk model with those in an associated averaged compound Poisson risk model. Numerical results suggest that one could use the results of the associated averaged compound Poisson risk model to approximate those for the two-state Markov-modulated dual risk model.

关键词： Dual risk model Markov-modulated risk model barrier strategy

Effect of c-fos antisense probe on prostaglandin E_2-induced upregulation of vascular endothelial growth factor mRNA in human liver cancer cells

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World Journal of Gastroenterology 2005年第28期11卷 4427-4430页

作者： Yong-Qi Li Ning Ren yi-hu wang Kai-Shan Tao Comprehensive Diagnostic and Therapeutic Center Xijing Hospital the Fourth Military Medical University Xi'an 710033 Shaanxi Province China Department of Hepatobiliary Surgery Xijing Hospitalthe Fourth Military Medical University Xi'an 710033 Shaanxi Province China

AIM: To examine the effect of prostaglandin E2 (PGE2) on the expression of vascular endothelial growth factor (VEGF) mRNA in the human hepatocellular carcinoma (HCC) HepG2 cells and the possible involvement of c-fos protein in this ***: human HCC HepG2 cells were divided into three groups treated respectively with PGE2, a combination of PGE2 and c-fos antisense oligodeoxynucleotide (ASO),and PGE2 plus c-fos sense oligodeoxynudeotide (SO). The expression of VEGF mRNA in HepG2 cells after different treatments was detected by reverse transcriptase-polymerase chain reaction (RT-PCR). The relative expression level of VEGF mRNA in HepG2 cells in each group was ***: Administration of PGE2 resulted in an increased expression of c-fosand VEGF mRNA in HepG2 cells. The relative expression level of c-fos mRNA reached the peak at 3 h (68.4±4.7%) after PGE2 treatment, which was significantly higher than that at 0 h (20.6±1.7%, P＜0.01).Whereas, the highest expression level of VEGF mRNA was observed at 6 h (100.5±6.1%) after PGE2 treatment, which was significantly higher than that at 0 h (33.2±2.4%,P＜0.01). C-fos ASO significantly reduced PGE2-induced VEGF mRNA expression in HepG2 ***: PGE2 increases the expression and secretion of VEGF in HCC cells by activating the transcription factor c-fos, promotes the angiogenesis of HCC and plays an important role in the pathogenesis of liver cancer.

关键词： Hepatocellular carcinoma Prostaglandin E2 c-fos , Vascular endothelial growth factor Angiogenesis

Repetitive transcranial magnetic stimulation in Alzheimer’s disease:effects on neural and synaptic rehabilitation

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Neural Regeneration Research 2025年第2期20卷 326-342页

作者： yi Ji Chaoyi Yang Xuerui Pang yibing Yan Yue Wu Zhi Geng Wenjie hu Panpan hu Xingqi Wu Kai wang Department of Neurology The First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui ProvinceChina Anhui Province Key Laboratory of Cognition and Neuropsychiatric Disorders HefeiAnhui ProvinceChina Collaborative Innovation Center of Neuropsychiatric Disorders and Mental Health HefeiAnhui ProvinceChina Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefeiAnhui ProvinceChina Department of Psychology and Sleep Medicine The Second Affiliated Hospital of Anhui Medical UniversityHefeiAnhui ProvinceChina

Alzheimer’s disease is a neurodegenerative disease resulting from deficits in synaptic transmission and *** Alzheimer’s disease brain tends to be hyperexcitable and hypersynchronized,thereby causing neurodegeneration and ultimately disrupting the operational abilities in daily life,leaving patients *** transcranial magnetic stimulation is a cost-effective,neuro-modulatory technique used for multiple neurological *** the past two decades,it has been widely used to predict cognitive decline;identify pathophysiological markers;promote neuroplasticity;and assess brain excitability,plasticity,and *** has also been applied to patients with dementia,because it can yield facilitatory effects on cognition and promote brain recovery after a neurological ***,its therapeutic effectiveness at the molecular and synaptic levels has not been elucidated because of a limited number of *** study aimed to characterize the neurobiological changes following repetitive transcranial magnetic stimulation treatment,evaluate its effects on synaptic plasticity,and identify the associated *** review essentially focuses on changes in the pathology,amyloidogenesis,and clearance pathways,given that amyloid deposition is a major hypothesis in the pathogenesis of Alzheimer’s *** mechanisms associated with repetitive transcranial magnetic stimulation procedures and different pathways mediating gene transcription,which are closely related to the neural regeneration process,are also ***,we discuss the outcomes of animal studies in which neuroplasticity is modulated and assessed at the structural and functional levels by using repetitive transcranial magnetic stimulation,with the aim to highlight future directions for better clinical translations.

关键词： Alzheimer’s disease amyloid deposition apoptotic mechanisms biomarker neural regeneration neurodegeneration repetitive transcranial magnetic stimulation synaptic plasticity

基于混合神经网络模型的磨粒电荷检测方法研究

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推进技术 2022年第6期43卷 356-364页

作者：薛倩王一虎中国民航大学电子信息与自动化学院天津300300

由于传统的滑油磨粒在线监测方法无法获取电荷分布位置信息,难以准确测量荷电颗粒数目及其携带的电荷量。为此,本文提出一种基于静电层析成像(Electrostatic tomography,EST)技术和深度学习算法的荷电颗粒检测方法。对EST传感器测量数... 详细信息

由于传统的滑油磨粒在线监测方法无法获取电荷分布位置信息,难以准确测量荷电颗粒数目及其携带的电荷量。为此,本文提出一种基于静电层析成像(Electrostatic tomography,EST)技术和深度学习算法的荷电颗粒检测方法。对EST传感器测量数据采用BP神经网络算法重建出测量截面上电荷的分布图像,采用卷积神经网络(Convolutional neural networks,CNN)算法分析重建图像以识别荷电颗粒数目,将识别的颗粒数目和传感器测量数据组合成输入向量,通过1个多层前馈网络确定带电颗粒数目、感应电荷值与颗粒电荷量值之间的映射关系,得到准确的各颗粒的电荷量值。实验结果表明:混合神经网络模型对数据样本的测量误差为9%,可满足滑油监测对于准确性的要求。

关键词：滑油检测荷电磨粒神经网络电荷检测静电层析成像

The effects of sustained-release new indapamide on blood pressure and quality of life in patients with hypertension

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中国临床康复 2002年第13期6卷 2012-2013页

作者： Zheng, Xiao-Rong wang, yi-hu Zhang, Can-Jiu Xijing Hospital Fourth Military Medical University Xi'an 710032 China

Objective: To observe the effects of sustained-release new indapadmide on blood pressure, and to acquire with its efficacy on the living quality of patients with hypertension. Methods: The 101 patients were randomly divided into B group with new indapamide and A group with old. The supine blood pressure was measured by sphygmomanometer, and the shape of whole day recorded by 24-hours dynamic sphygmometrograph before and after 6 months of experience. Results: The antihypertensive effects of two medicines were both significant, patients in B group had lower mean nocturnal diastolic blood pressure by statistical analysis. The cases of the hypokalemic side in B group were fewer than that in A group. The living quality of patients in B group was improved significantly. Conclusion: Both drugs have almost equal efficacy in management of the hypertension, and the new one brought less the hypokalemia and higher quality of life.

关键词：吲哒帕胺缓释剂高血压血压生存质量

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江苏沿江各市工业绿色化程度的模糊评价

长江流域资源与环境 2008年第2期17卷 170-174页

作者：王宜虎陈雯中国科学院南京地理与湖泊研究所

工业绿色化即工业企业逐步减少污染排放,实现环境无害化的过程,这一过程的进展情况直接影响到区域可持续发展水平。从工业绿色化意识、工业绿色化管理、工业绿色化绩效3个方面构建了区域工业绿色化发展的评价指标体系。为了使评价结果... 详细信息

工业绿色化即工业企业逐步减少污染排放,实现环境无害化的过程,这一过程的进展情况直接影响到区域可持续发展水平。从工业绿色化意识、工业绿色化管理、工业绿色化绩效3个方面构建了区域工业绿色化发展的评价指标体系。为了使评价结果更为科学合理,还对江苏沿江8市的244家工业企业进行问卷调查,在此基础上,结合各市单位产值能耗及污染排放强度、水循环利用率、废水达标排放率、废物综合利用率等工业绿色化绩效的实际值建立多级模糊综合评价模型,对江苏省沿江8市的工业绿色化发展水平进行评价。结果发现,苏州、无锡等苏南经济较发达地区的工业绿色化水平较高,而扬州、镇江、泰州等苏中地区的工业绿色化水平较低。最后提出了加快工业绿色化发展,缩小地区间差距的具体建议。

关键词：工业绿色化层次分析法模糊综合评价江苏沿江地区

Near-perfect replication on amorphous alloys through active force modulation based on machine learning/neural network parameter prediction

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 181-191页

作者： Senkuan Meng Zheng wang Ruisong Zhu Ruijie Liu Jiang Ma Lina hu Weihua wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University College of Mechatronics and Control Engineering Shenzhen University Songshan Lake Materials Laboratory Institute of Physics Chinese Academy of Sciences

As a microforming technique, micro/nano-structural replication possesses advantages of high precision and efficiency. With the remarkable superplasticity in the supercooled liquid region, amorphous alloys or metallic glasses(MGs) are regarded as ideal materials for miniature fabrication. However, due to the intrinsic metastable nature of supercooled liquids, the design of imprinting processes for MGs poses a challenge. In the past, process parameters have largely relied on trial-and-error *** this work, a low-frequency active force modulation system is employed to apply a stable, precise, and real-time feedback stress field for imprinting of MG samples. Low-frequency vibrations can facilitate the filling of microstructures on the template surface by reducing the effective viscosity of the supercooled liquid. With the dataset composed of orthogonal experiments, a machine learning strategy based on back-propagation(BP) neural networks was utilized to construct a 3D parameter space for temperature, stress, and time, and to predict the corresponding filling ratio. Furthermore, the optimal combination of imprinting process parameters was identified, and its filling ratio was experimentally validated to reach as high as 0.94. The near-perfect replication of microstructures confirms the superiority of the active force modulation system and the data-driven strategy of machine learning-assisted parameter design. At the same time, this one-step microforming process provides a new approach to addressing the accuracy-cost trade-off dilemma in precision manufacturing.

关键词： metallic glass amorphous alloy microforming imprinting machine learning

Boosting Oxygen Evolution Reaction Performance on NiFe‑Based Catalysts Through d‑Orbital Hybridization

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Nano-Micro Letters 2025年第1期17卷 281-292页

作者： Xing wang Wei Pi Sheng hu Haifeng Bao Na Yao Wei Luo State Key Laboratory of New Textile Materials and Advanced Processing Technology Key Laboratory of New Textile Materials and Applications of Hubei ProvinceSchool of Materials Science and EngineeringWuhan Textile UniversityWuhan 430200People’s Republic of China College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072People’s Republic of China

Anion-exchange membrane water electrolyzers(AEMWEs)for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based *** introducing a third metal into NiFe-based catalysts to construct asymmetrical M-NiFe units,the d-orbital and electronic structures can be adjusted,which is an important strategy to achieve sufficient oxygen evolution reaction(OER)performance in ***,the ternary NiFeM(M:La,Mo)catalysts featured with distinct M-NiFe units and varying d-orbitals are reported in this *** and theoretical calculation results reveal that the doping of La leads to optimized hybridization between d orbital in NiFeM and 2p in oxygen,resulting in enhanced adsorption strength of oxygen intermediates,and reduced rate-determining step energy barrier,which is responsible for the enhanced OER *** critically,the obtained NiFeLa catalyst only requires 1.58 V to reach 1 A cm^(−2) in an anion exchange membrane electrolyzer and demonstrates excellent long-term stability of up to 600 h.

关键词： NiFe-based catalysts d-orbital coupling Oxygen evolution reaction Anion exchange membrane electrolyzer

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南京市经济发展与环境污染关系的实证研究

长江流域资源与环境 2006年第2期15卷 142-146页

作者：王宜虎崔旭陈雯中国科学院南京地理与湖泊研究所

根据南京市1991～2003年经济与环境数据，分析经济发展与环境污染的相互关系，建立了南京市经济增长与环境污染水平的计量模型，进而评价了南京市的环境保护政策。研究表明：作为一个重化工业城市，南京市自20世纪90年代以来，在经济高... 详细信息

根据南京市1991～2003年经济与环境数据，分析经济发展与环境污染的相互关系，建立了南京市经济增长与环境污染水平的计量模型，进而评价了南京市的环境保护政策。研究表明：作为一个重化工业城市，南京市自20世纪90年代以来，在经济高速发展的情况下，其环境恶化程度逐步得到遏制，部分环境指标与人均GDP演替轨迹呈现显著的环境库兹涅茨曲线特征。这主要归功于南京市政府近年来有效的环境政策和巨额的环境投资。

关键词：环境库兹涅茨曲线经济增长与环境污染计量模型环境政策南京市