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MRI多b值DWI定量参数诊断实性肺结节良恶性的价值研究

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中国CT和MRI杂志 2025年第1期23卷 63-65,81页

作者：于博钱伟军李立赵文开封市中心医院影像科河南开封475000

目的探讨MRI多b值DWI定量参数对实性肺结节良恶性的诊断价值。方法分析本院经手术、穿刺活检及随访证实80例实性肺结节的临床及MRI资料为研究对象,恶性肺结节50例,良性30例。80例患者均行MRI多b值DWI序列检查, b值选取300、600、900、... 详细信息

目的探讨MRI多b值DWI定量参数对实性肺结节良恶性的诊断价值。方法分析本院经手术、穿刺活检及随访证实80例实性肺结节的临床及MRI资料为研究对象,恶性肺结节50例,良性30例。80例患者均行MRI多b值DWI序列检查, b值选取300、600、900、 1200s/mm^(2)。计算不同b值肺结节的表观弥散系数(ADC)值及DWI图像上测量病灶/脊髓信号比值(LSR)、病灶/骨骼肌信号比值(LMR)。符合正态分布的计量资料,采用组间t检验比较良恶性实性肺结节DWI各参数的差异,对于统计学分析有差异的参数,采用ROC并计算出AUC,分析DWI各参数诊断实性肺结节良恶性的诊断效能,获取最佳b值和阈值。结果 b值选取300、600、900、1200s/mm^(2)时,恶性肺结节ADC值均低于良性肺结节,差异有统计学意义(P0.05),ROC曲线的AUC分别为0.721、0.948、0.737。当b值取600s/mm^(2)时,LSR的诊断效能最大,鉴别诊断肺结节良恶性病变的阈值为0.36。b值选取300、600、900、1200s/mm^(2)时,恶性肺结节LMR与良性肺结节各参数差异无统计学意义(P>0.05)。结论MRI多b值DWI定量参数鉴别实性肺结节良恶性有较高的价值,b值取600 s/mm^(2)时,LSR的诊断效能最大,其次b值取900s/mm^(2)时,ADC值的诊断效能最大。

关键词： DWI定量参数良性肺结节恶性肺结节鉴别诊断价值

The Impact of Floods on the Mobility of Automobile Commuters in Shanghai Under Climate Change

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International Journal of Disaster Risk Science 2024年第6期15卷 986-1000页

作者： qian Yao Xinmeng Shan Mengya li jun Wang Key Laboratory of Geographic Information Science of Ministry of Education East China Normal University Institute for National Safety and Emergency Management East China Normal University School of Geographic Sciences East China Normal University Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and Environment Chinese Academy of Sciences China-Pakistan Joint Research Center on Earth Sciences CAS-HEC School of Public Management East China Normal University

As sea level rises, low-lying coastal cites face increasing threat of flood disruption, particularly in terms of human mobility. Commuters are vulnerable to bad weather, as it is difficult to cancel trips even in extreme weather conditions. Using Shanghai's automobile commuting population as an example, we categorized commuters by travel distance and income level to assess disruptions and delays due to floods, considering future sea level rise. The results show that local flooding disrupts commuting patterns by affecting roadways, with disruption decreasing with distance from the flooded area. This offers a mobility perspective on the indirect impacts of floods. During baseline flood events, long-distance commuters and the lowincome group are most affected, while short-distance commuters and the high-income group are less impacted. As sea level rises, floods will threaten all commuting groups, especially the high-income group. Using inaccessibility-commuting delay bivariate maps, this study revealed how socioeconomic differences impact mobility recovery after floods under climate change. The research highlights the differential impacts of floods on various socioeconomic groups in the context of climate change, offering insights for future urban planning and disaster mitigation strategies.

关键词： Climate change Commuting patterns Human mobility Indirect flood effect Shanghai Socioeconomic disparities

Microstructure and properties of electroformed nickel under different waveform conditions

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Rare Metals 2023年第1期42卷 320-326页

作者： Jing li Jian-Gang qian Xiao-Tian Hu Tie-jun li Hai-Ting li School of Chemistry and Environment Beihang UniversityBeijing100191China

In order to prepare electroformed nickel with excellent properties,the effect of different waveforms on microstructure and mechanical properties was investigated by optical microscopy(OM),X-ray diffraction(XRD) and tensile test,*** results show that the samples are composed of micron columnar grains with high-density nanoscale coherent twin boundaries which are parallel to the growth *** tensile strength and elongation display opposite tendency with the increase in current density when direct current(DC) electroforming was ***,under the condition of pulse current(unidirectional,bidirectional) electroforming,the change regulation of tensile strength and elongation is close while cathode(peak,positive peak) current density *** results show that electroformed nickel layers with high purity are all fcc crystal configuration under different conditions of the current *** nickel layers formed under bidirectional pulse current behave superior global performance with tensile strength of 692.0 MPa and elongation of 27.6 %.

关键词： Current waveform Electroformed nickel Organization Mechanical properties

Statistical Analyses of Wave Height Distribution for Multidirectional Irregular Waves over A Sloping Bottom

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China Ocean Engineering 2021年第4期35卷 504-517页

作者： GAO jun-liang CHEN Hong-zhou MEI li-li liU Zhen liU qian School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China School of Marine Engineering Equipment Zhejiang Ocean UniversityZhoushan 316022China Henan Province Construction Engineering Quality Inspection and Testing Center Station Co.Ltd. Zhengzhou 450053China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

The main objective of this paper is to examine the influences of both the principal wave direction and the directional spreading parameter of the wave energy on the wave height evolution of multidirectional irregular waves over an impermeable sloping bottom and to propose an improved wave height distribution model based on an existing classical *** numerical model FUNWAVE 2.0,based on a fully nonlinear Boussinesq equation,is employed to simulate the propagation of multidirectional irregular waves over the sloping *** of wave heights derived from wave trains with various principal wave directions and different directional spreading parameters are *** show that both the principal wave direction and the wave directional spread have significant influences on the wave height evolution on a varying coastal *** shoaling effect for the wave height is obviously weakened with the increase of the principal wave direction and with the decrease of the directional spreading *** the simulated data,the classical Klopman wave height distribution model is improved by considering the influences of both *** is found that the improved model performs better in describing the wave height distribution for the multidirectional irregular waves in shallow water.

关键词： wave height distribution multidirectional waves irregular waves sloping bottom FUNWAVE 2.0 model

4D Printing:History and Recent Progress

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Chinese Journal of Polymer Science 2018年第5期36卷 563-575页

作者： Jing-jun Wu li-Mei Huang qian Zhao Tao Xie State Key Laboratory of Chemical Engineering College of Chemical and Biological Engineering Zhejiang University

4D printing has attracted great interest since the concept was introduced in 2012. The past 5 years have witnessed rapid advances in both 4D printing processes and materials. Unlike 3D printing, 4D printing allows the printed part to change its shape and function with time in response to change in external conditions such as temperature, light, electricity, and water. In this review, we first overview the history of 4D printing and discuss its definition. We then summarize recent technological advances in 4D printing with focuses on methods, materials, and their intrinsic links. Finally, we discuss potential applications and offer perspectives for this exciting new field.

关键词： 4D printing Shape memory polymer Hydrogel Multi-material structure Single-material structure

Integrating lipidomics and gut microbiota to study the anti-hyperlipidemia effect of Sargentodoxae Caulis extract

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Traditional Medicine Research 2025年第1期10卷 1-11页

作者： Xiao-Xiao Zhang li Jia Xiu-jun Zhan Charity Ngina Qing-Rui Zhang Xiao-Ge li Qi-Bao Jiang Shi Bai Miao-Miao Jiang National Key Laboratory of Chinese Medicine Modernization Tianjin University of Traditional Chinese MedicineTianjin 301617China Haihe Laboratory of Modern Chinese Medicine Tianjin 301617China School of Medicine Taizhou UniversityTaizhou 318000China.

Background:Sargentodoxae Caulis(SC)is the vine stem of Sargentodoxa Cuneata(Oliv.)Rehd.&*** in ***,and it in traditional Chinese medicine has been known for promoting blood circulation and removing blood stasis as recorded in the ancient book“Illustrated Classics of Materia Medica”.It has been used effectively to treat blood stasis too in modern clinical ***,the anti-hyperlipidemia effect of SC is not fully *** paper aims at exploring the use of SC stems to improve the balance of blood lipids in the body,and its new role in treating ***:The effects of SC extract on hyperlipidemia were explored by combining lipidomics and gut ***,we explored the potential mechanism of SC in treating hyperlipidemia by pathway ***:The results showed that the stem extract of SC could restore the physiological and biochemical indices of hyperlipidemia in mice,as well as repair the morphological and structural damage to *** to the Model group,the SC extract significantly reduced the liver index,epididymal fat index,and Lee’s *** also significantly decreased serum levels of total cholesterol,triglycerides,low-density lipoprotein cholesterol,peroxisome proliferator-activated receptor gamma(PPAR-γ),D-lactate,and free fatty acids,while significantly increasing the relative content of peroxisome proliferator-activated receptor alpha(PPAR-α).These changes were statistically ***-targeted lipidomics,based on LC-MS,were utilized to investigate the lipid metabolism characteristics in serum,liver,and epididymal fat of the *** was observed that,compared to the blank group,the Model group exhibited significant changes primarily in glycerol lipids and *** treatment group also displayed alterations in these lipids.A total of 38,81,and 27 differential lipids were identified in serum,liver,and epididymal fat samples,*** these,14 common differenti

关键词： hyperlipidemia Sargentodoxae Caulis lipidomics intestinal flora

Two-dimensional analysis of progressive delamination in thin film electrodes

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Acta Mechanica Sinica 2018年第2期34卷 359-370页

作者： Mei liu Bo Lu Dong-li Shi jun-qian Zhang Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Department of Mechanics Shanghai University Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai University Materials Genome Institute Shanghai University

By employing the two-dimensional analysis, i.e.,plane strain and plane stress, a semi-analytical method is developed to investigate the interfacial delamination in electrodes. The key parameters are obtained from the governing equations, and their effects on the evolution of the delamination are evaluated. The impact of constraint perpendicular to the plane is also investigated by comparing the plane strain and plane stress. It is found that the delamination in the plane strain condition occurs easier, indicating that the constraint is harmful to maintain the structure stability. According to the obtained governing equations, a formula of the dimensionless critical size for delamination is provided, which is a function of the maximum volumetric strain and the Poisson’s ratio of the active layer.

关键词： lithium-ion battery Thin film electrode Delamination Critical size

Transforming growth factor-beta 1 enhances discharge activity of cortical neurons

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Neural Regeneration Research 2025年第2期20卷 548-556页

作者： Zhihui Ren Tian li Xueer liu Zelin Zhang Xiaoxuan Chen Weiqiang Chen Kangsheng li Jiangtao Sheng Department of Microbiology and Immunology Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular ImmunopathologyShantou University Medical CollegeShantouGuangdong ProvinceChina Department of Neurosurgery First Affiliated Hospital of Shantou University Medical CollegeShantouGuangdong ProvinceChina

Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system *** neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may depend on the pathological process and cell types ***-gated sodium channels(VGSCs)are essential ion channels for the generation of action potentials in neurons,and are involved in various neuroexcitation-related ***,the effects of TGF-β1 on the functional properties of VGSCs and firing properties in cortical neurons remain *** this study,we investigated the effects of TGF-β1 on VGSC function and firing properties in primary cortical neurons from *** found that TGF-β1 increased VGSC current density in a dose-and time-dependent manner,which was attributable to the upregulation of Nav1.3 *** VGSC current density and Nav1.3 expression were significantly abolished by preincubation with inhibitors of mitogen-activated protein kinase kinase(PD98059),p38 mitogen-activated protein kinase(SB203580),and jun NH2-terminal kinase 1/2 inhibitor(SP600125).Interestingly,TGF-β1 significantly increased the firing threshold of action potentials but did not change their firing rate in cortical *** findings suggest that TGF-β1 can increase Nav1.3 expression through activation of the ERK1/2-JNK-MAPK pathway,which leads to a decrease in the firing threshold of action potentials in cortical neurons under pathological ***,this contributes to the occurrence and progression of neuroexcitatory-related diseases of the central nervous system.

关键词： central nervous system cortical neurons ERK firing properties JNK Nav1.3 p38 transforming growth factor-beta 1 traumatic brain injury voltage-gated sodium currents

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鄂尔多斯盆地南部长6段储层流体识别研究

中外能源 2025年第1期30卷 65-70页

作者：李倩杨静王茜延长油田股份有限公司南泥湾采油厂陕西延安716000 延长油田股份有限公司下寺湾采油厂陕西延安716000

鄂尔多斯盆地南部长6油层组为典型的低孔低渗储层,储层流体性质识别难度大,制约了油藏的高效开发。首先通过储层岩石学分析,明确储层岩石类型。通过岩心观察、岩心物性分析,确定储层物性特征,将实验分析结果与测井资料相结合,对岩心及... 详细信息

鄂尔多斯盆地南部长6油层组为典型的低孔低渗储层,储层流体性质识别难度大,制约了油藏的高效开发。首先通过储层岩石学分析,明确储层岩石类型。通过岩心观察、岩心物性分析,确定储层物性特征,将实验分析结果与测井资料相结合,对岩心及分析资料进行归位处理,获取储层孔隙度与声波时差参数,建立声波时差测井孔隙度解释模型。分析渗透率与孔隙度、渗透率与微电位/微梯度比值的关系,建立渗透率解释模型。基于岩心观察、试油试产结果,分析孔隙度、渗透率与储层含油性关系,确定有效储层物性下限。建立声波时差-电阻率交会图版,结合Fisher判别法开展流体识别。结果表明:长6油层组有效储层岩性、含油性下限为细砂岩、油斑级别;孔隙度、渗透率下限分别为7.4%、0.1×10^(-3)μm^(2);油水同层、差油层、油层的电阻率>20Ω·m且声波时差>230μs/m;利用声波时差-电阻率交会图版识别长6段储层流体,综合精度为78.7%,分层识别时长61、长62、长63段识别精度分别为85.3%、88.5%、91.7%;利用Fisher判别法进行识别,储层流体的综合正判率为86.3%。

关键词：流体识别孔隙度渗透率声波时差含油性电阻率