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Comparative proteomic analysis of plasma exosomes reveals the functional contribution of N-acetyl-alpha-glucosaminidase to Parkinson’s disease
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作者 Yuan Zhao Yidan Zhang +6 位作者 Xin liu Jian Zhang Ya Gao Shuyue Li Cui Chang xiang liu Guofeng Yang 《Neural Regeneration Research》 SCIE CAS 2025年第10期2998-3012,共15页
Parkinson’s disease is the second most common progressive neurodegenerative disorder,and few reliable biomarkers are available to track disease progression.The proteins,DNA,mRNA,and lipids carried by exosomes reflect... Parkinson’s disease is the second most common progressive neurodegenerative disorder,and few reliable biomarkers are available to track disease progression.The proteins,DNA,mRNA,and lipids carried by exosomes reflect intracellular changes,and thus can serve as biomarkers for a variety of conditions.In this study,we investigated alterations in the protein content of plasma exosomes derived from patients with Parkinson’s disease and the potential therapeutic roles of these proteins in Parkinson’s disease.Using a tandem mass tag-based quantitative proteomics approach,we characterized the proteomes of plasma exosomes derived from individual patients,identified exosomal protein signatures specific to patients with Parkinson’s disease,and identified N-acetyl-alpha-glucosaminidase as a differentially expressed protein.N-acetyl-alpha-glucosaminidase expression levels in exosomes from the plasma of patients and healthy controls were validated by enzyme-linked immunosorbent assay and western blot.The results demonstrated that the exosomal N-acetyl-alpha-glucosaminidase concentration was not only lower in Parkinson’s disease,but also decreased with increasing Hoehn-Yahr stage,suggesting that N-acetyl-alpha-glucosaminidase could be used to rapidly evaluate Parkinson’s disease severity.Furthermore,western blot and immunohistochemistry analysis showed that N-acetyl-alpha-glucosaminidase levels were markedly reduced both in cells treated with 1-methyl-4-phenylpyridinium and cells overexpressingα-synuclein compared with control cells.Additionally,N-acetyl-alpha-glucosaminidase overexpression significantly increased cell viability and inhibitedα-synuclein expression in 1-methyl-4-phenylpyridinium-treated cells.Taken together,our findings demonstrate for the first time that exosomal N-acetyl-alpha-glucosaminidase may serve as a biomarker for Parkinson’s disease diagnosis,and that N-acetyl-alpha-glucosaminidase may reduceα-synuclein expression and 1-methyl-4-phenylpyridinium-induced neurotoxicity,thus providing a new therapeutic target for Parkinson’s disease. 展开更多
关键词 biomarker diagnosis EXOSOMES N-acetyl-alpha-glucosaminidase Parkinson’s disease proteomic α-synuclein
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一种阴离子浸出策略合成金属羟基氧化物用于电催化甘油氧化
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作者 王烨 葛瑞翔 +2 位作者 刘翔 李敬 段昊泓 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第7期43-46,共4页
亲核氧化反应在可持续生产增值化学品中扮演着重要角色。电催化甘油氧化反应作为亲核氧化反应的一种重要类型,可以制得包括甲酸在内的C_(1)至C_(3)衍生产物。非贵金属氢氧化物/羟基氧化物被广泛应用于甘油氧化反应,但在中等电位下难以... 亲核氧化反应在可持续生产增值化学品中扮演着重要角色。电催化甘油氧化反应作为亲核氧化反应的一种重要类型,可以制得包括甲酸在内的C_(1)至C_(3)衍生产物。非贵金属氢氧化物/羟基氧化物被广泛应用于甘油氧化反应,但在中等电位下难以达到工业级电流密度(大于300 mA·cm^(-2))。研究表明,氢氧化物/羟基氧化物催化的甘油氧化反应通过间接氧化机理进行,即通过电生成的含有亲电吸附氧的羟基氧化物氧化亲核试剂(甘油)。因此,理解甘油氧化反应中电催化剂的演变至关重要。在本文中,通过循环伏安法活化钼酸镍(NiMoO_(4)),开发了一种钼掺杂的羟基氧化镍(Mo-NiOOH)催化剂。通过多种表征方法对Mo-NiOOH进行了系统表征,结果显示,Mo-NiOOH继承了NiMoO_(4)前驱体的纳米片阵列形貌,但Mo含量降低,证明循环伏安法活化后实现了从氧化物到羟基氧化物的相重构。此外,Mo-NiOOH中Ni^(3+)/Ni^(2+)的比例高于循环伏安法活化制备的NiOOH。在活化过程中,Mo物种从NiMoO_(4)中浸出,制备得到的Mo-NiOOH保留了NiMoO_(4)前驱体的纳米片阵列形貌。与氢氧化镍(Ni(OH)_(2))经循环伏安法活化合成的NiOOH相比,Mo-NiOOH具有更高的Ni^(3+)/Ni^(2+)比例以及更高的电化学比表面积(ECSAs),且促进了Ni^(2+)氧化为Ni^(3+)。因此,Mo-NiOOH达到高电流密度(400mA·cm^(-2))的电位(1.51V vs.RHE)低于NiOOH(1.84 V vs.RHE)。此外,Mo-NiOOH表现出高于NiOOH的甲酸盐法拉第效率(84.7%vs.59.6%),表明钼掺杂加速了碳-碳键断裂。多电位阶跃实验显示,NiOOH和Mo-NiOOH催化的甘油电氧化通过类似的羟基氧化物介导的间接氧化机理进行。原位电化学阻抗谱和原位拉曼光谱证实,Mo掺杂促进了甘油氧化反应动力学以及Ni^(2+)氧化为Ni^(3+)的过程,导致Mo-NiOOH比NiOOH具有更高的活性和甲酸选择性。本研究通过可溶性阴离子浸出策略来调节羟基氧化物表面结构,为设计高性能亲核氧化反应电催化剂提供了指导。 展开更多
关键词 循环伏安法活化 电催化 甘油电氧化 羟基氧化物 重构
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Facile synthesis of Cu-doped manganese oxide octahedral molecular sieve for the efficient degradation of sulfamethoxazole via peroxymonosulfate activation 被引量:1
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作者 Yuhua Qiu Yingping Huang +2 位作者 Yanlan Wang xiang liu Di Huang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第12期2770-2780,共11页
Advanced processes for peroxymonosulfate(PMS)-based oxidation are efficient in eliminating toxic and refractory organic pol-lutants from sewage.The activation of electron-withdrawing HSO_(5)^(-)releases reactive speci... Advanced processes for peroxymonosulfate(PMS)-based oxidation are efficient in eliminating toxic and refractory organic pol-lutants from sewage.The activation of electron-withdrawing HSO_(5)^(-)releases reactive species,including sulfate radical(·SO_(4)^(-)),hydroxyl radical(·OH),superoxide radical(·O_(2)^(-)),and singlet oxygen(1O_(2)),which can induce the degradation of organic contaminants.In this work,we synthesized a variety of M-OMS-2 nanorods(M=Co,Ni,Cu,Fe)by doping Co^(2+),Ni^(2+),Cu^(2+),or Fe^(3+)into manganese oxide oc-tahedral molecular sieve(OMS-2)to efficiently remove sulfamethoxazole(SMX)via PMS activation.The catalytic performance of M-OMS-2 in SMX elimination via PMS activation was assessed.The nanorods obtained in decreasing order of SMX removal rate were Cu-OMS-2(96.40%),Co-OMS-2(88.00%),Ni-OMS-2(87.20%),Fe-OMS-2(35.00%),and OMS-2(33.50%).Then,the kinetics and struc-ture-activity relationship of the M-OMS-2 nanorods during the elimination of SMX were investigated.The feasible mechanism underly-ing SMX degradation by the Cu-OMS-2/PMS system was further investigated with a quenching experiment,high-resolution mass spec-troscopy,and electron paramagnetic resonance.Results showed that SMX degradation efficiency was enhanced in seawater and tap water,demonstrating the potential application of Cu-OMS-2/PMS system in sewage treatment. 展开更多
关键词 SULFAMETHOXAZOLE manganese oxide octahedral molecular sieve PEROXYMONOSULFATE sewage treatment COPPER
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机制砂对喷射混凝土强度影响试验研究
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作者 唐斌 陈清运 +4 位作者 梅林芳 向柳 邵春悦 石啸天 魏敬芮 《现代矿业》 CAS 2024年第5期190-195,共6页
以金山店铁矿机制砂为研究对象,对2种不同种类母岩机制砂分别开展X射线衍射试验、筛分试验和抗压强度试验,并与黄砂进行对比。试验结果表明,母岩为火成岩的机制砂喷射混凝土抗压强度最高,黄砂次之,沉积岩最低;长石含量是影响机制砂混凝... 以金山店铁矿机制砂为研究对象,对2种不同种类母岩机制砂分别开展X射线衍射试验、筛分试验和抗压强度试验,并与黄砂进行对比。试验结果表明,母岩为火成岩的机制砂喷射混凝土抗压强度最高,黄砂次之,沉积岩最低;长石含量是影响机制砂混凝土强度的主要因素,其次矿物的结晶结构和晶粒大小也影响机制砂强度;沉积岩机制砂母岩强度高、细度模数大,机制砂混凝土抗压强度与黄砂混凝土相比降低了14.4%;建议选用长石含量高,抗压强度适中的岩石制备的机制砂来作为井下喷浆用砂。 展开更多
关键词 机制砂混凝土 X射线衍射 筛分试验 抗压强度试验
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Research on Rotating Machinery Fault Diagnosis Based on Improved Multi-target Domain Adversarial Network 被引量:1
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作者 Haitao Wang xiang liu 《Instrumentation》 2024年第1期38-50,共13页
Aiming at the problems of low efficiency,poor anti-noise and robustness of transfer learning model in intelligent fault diagnosis of rotating machinery,a new method of intelligent fault diagnosis of rotating machinery... Aiming at the problems of low efficiency,poor anti-noise and robustness of transfer learning model in intelligent fault diagnosis of rotating machinery,a new method of intelligent fault diagnosis of rotating machinery based on single source and multi-target domain adversarial network model(WDMACN)and Gram Angle Product field(GAPF)was proposed.Firstly,the original one-dimensional vibration signal is preprocessed using GAPF to generate the image data including all time series.Secondly,the residual network is used to extract data features,and the features of the target domain without labels are pseudo-labeled,and the transferable features among the feature extractors are shared through the depth parameter,and the feature extractors of the multi-target domain are updated anatomically to generate the features that the discriminator cannot distinguish.The modelt through adversarial domain adaptation,thus achieving fault classification.Finally,a large number of validations were carried out on the bearing data set of Case Western Reserve University(CWRU)and the gear data.The results show that the proposed method can greatly improve the diagnostic efficiency of the model,and has good noise resistance and generalization. 展开更多
关键词 multi-target domain domain-adversarial neural networks transfer learning rotating machinery fault diagnosis
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Expediting^(*)OH accumulation kinetics on metal-organic frameworks-derived CoOOH with CeO_(2) “accelerator” for electrocatalytic 5-hydroxymethylfurfural oxidation valorization
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作者 Peiyun Zhou Haokun Pan +3 位作者 Guangtong Hai xiang liu Xiubing Huang Ge Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期721-732,共12页
In this work,nickel foam supported CeO_(2)-modified CoBDC(BDC stands for terephthalic acid linker)metal-organic frameworks(NF/CoBDC@CeO_(2)) are prepared by hydrothermal and subsequent impregnation methods,which can b... In this work,nickel foam supported CeO_(2)-modified CoBDC(BDC stands for terephthalic acid linker)metal-organic frameworks(NF/CoBDC@CeO_(2)) are prepared by hydrothermal and subsequent impregnation methods,which can be further transformed to NF/CoOOH@CeO_(2) by reconstruction during the electrocatalytic test.The obtained NF/CoOOH@CeO_(2) exhibits excellent performance in electrocatalytic oxidation of 5-hydroxymethylfurfural(HMF) because the introduction of CeO_(2) can optimize the electronic structure of the heterointerface and accelerate the accumulation of ^(*)OH.It requires only a potential of 1.290 V_(RHE) to provide a current density of 50 mA cm^(-2) in 1.0 M KOH+50 mM HMF,which is 222 mV lower than that required in 1,0 M KOH(1.512 V_(RHE)).In addition,density-functional theory calculation results demonstrate that CeO_(2) biases the electrons to the CoOOH side at the heterointerface and promotes the adsorption of ^(*)OH and ^(*)HMF on the catalyst surface,which lower the reaction energy barrier and facilitate the electrocata lytic oxidation process. 展开更多
关键词 CeO_(2) Metal-organic frameworks 5-Hydroxymethylfurfural oxidation reaction HETEROINTERFACE Reconstruction
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Comparison of the effect of different external electrodes on discharge plasma-assisted diffusion flame stabilization
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作者 Siyin ZHOU xiang liu +1 位作者 Wansheng NIE Shuhui YUAN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第10期123-132,共10页
To optimize the design of plasma injectors,the influence of different external electrodes on plasma-assisted flame stabilization was assessed by using a nonequilibrium plasma injector flame control setup.The electrica... To optimize the design of plasma injectors,the influence of different external electrodes on plasma-assisted flame stabilization was assessed by using a nonequilibrium plasma injector flame control setup.The electrical characteristics of the injector,flame structure parameters,flame intensity,discharge power,and cost-to-effectiveness ratio under different external electrodes(four mesh electrodes and one copper foil electrode)were analyzed using electrical and optical methods.The results show that reducing the mesh size of the external electrode leads to a decrease in breakdown voltage.Compared with a ceramic dielectric barrier-based injector,an injector with a quartz dielectric barrier produces a higher breakdown voltage under the same conditions.For the same actuation voltage,the discharge current increases as the mesh size of the external electrode decreases,and combustion is enhanced by the discharge plasma;therefore,it is better to adopt a smaller mesh hole size to realize good flame stabilization under a lower actuation voltage.However,under the studied working conditions,reducing the mesh hole size of the external electrode increases the cost-to-effectiveness ratio of plasma injector-based flame stabilization.Thus,considering the cost-to-effectiveness ratio and the weight of the injector,an external electrode with a larger mesh hole size should be chosen,which contradicts the above rule. 展开更多
关键词 flame stabilization alternating current driven dielectric barrier discharge plasma injector plasma-assisted combustion external electrode
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Retinal ischemia-reperfusion injury and pretreatment with Lycium barbarum glycopeptide
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作者 Yan-Xia Wu Shuo Yin +3 位作者 Shan-Shan Song xiang liu Yu-Xuan Deng Xue-Jing Lu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第9期1599-1605,共7页
AIM:To investigate the antioxidant protective effect of Lycium barbarum glycopeptide(LbGP)pretreatment on retinal ischemia-reperfusion(I/R)injury(RIRI)in rats.METHODS:RIRI was induced in Sprague Dawley rats through an... AIM:To investigate the antioxidant protective effect of Lycium barbarum glycopeptide(LbGP)pretreatment on retinal ischemia-reperfusion(I/R)injury(RIRI)in rats.METHODS:RIRI was induced in Sprague Dawley rats through anterior chamber perfusion,and pretreatment involved administering LbGP via gavage for 7d.After 24h of reperfusion,serum alanine aminotransferase(ALT),aspartate aminotransferase(AST),and creatinine(CREA)levels,retinal structure,expression of Caspase-3 and Caspase-8,superoxide dismutase(SOD)activity,and malondialdehyde(MDA)in the retina were measured.RESULTS:The pretreatment with LbGP effectively protected the retina and retinal tissue from edema and inflammation in the ganglion cell layer(GCL)and nerve fiber layer(NFL)of rats subjected to RIRI,as shown by light microscopy and optical coherence tomography(OCT).Serum AST was higher in the model group than in the blank group(P=0.042),but no difference was found in ALT,AST,and CREA across the LbGP groups and model group.Caspase-3 expression was higher in the model group than in the blank group(P=0.006),but no difference was found among LbGP groups and the model group.Caspase-8 expression was higher in the model group than in the blank group(P=0.000),and lower in the 400 mg/kg LbGP group than in the model group(P=0.016).SOD activity was lower in the model group than in the blank group(P=0.001),and the decrease was slower in the 400 mg/kg LbGP group than in the model group(P=0.003).MDA content was higher in the model group than in the blank group(P=0.001),and lower in the 400 mg/kg LbGP group than in the model group(P=0.016).The pretreatment with LbGP did not result in any observed liver or renal toxicity in the model.CONCLUSION:LbGP pretreatment exhibits dosedependent anti-inflammatory,and antioxidative effects by reducing Caspase-8 expression,preventing declines of SOD activity,and decreasing MDA content in the RIRI rat model. 展开更多
关键词 retinal ischemia-reperfusion Lycium barbarum glycopeptide PRETREATMENT ANTI-INFLAMMATORY ANTIOXIDATIVE RAT
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An Efficient and Provably Secure SM2 Key-Insulated Signature Scheme for Industrial Internet of Things
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作者 Senshan Ouyang xiang liu +3 位作者 Lei liu Shangchao Wang Baichuan Shao Yang Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期903-915,共13页
With the continuous expansion of the Industrial Internet of Things(IIoT),more andmore organisations are placing large amounts of data in the cloud to reduce overheads.However,the channel between cloud servers and smar... With the continuous expansion of the Industrial Internet of Things(IIoT),more andmore organisations are placing large amounts of data in the cloud to reduce overheads.However,the channel between cloud servers and smart equipment is not trustworthy,so the issue of data authenticity needs to be addressed.The SM2 digital signature algorithm can provide an authentication mechanism for data to solve such problems.Unfortunately,it still suffers from the problem of key exposure.In order to address this concern,this study first introduces a key-insulated scheme,SM2-KI-SIGN,based on the SM2 algorithm.This scheme boasts strong key insulation and secure keyupdates.Our scheme uses the elliptic curve algorithm,which is not only more efficient but also more suitable for IIoT-cloud environments.Finally,the security proof of SM2-KI-SIGN is given under the Elliptic Curve Discrete Logarithm(ECDL)assumption in the random oracle. 展开更多
关键词 KEY-INSULATED SM2 algorithm digital signature Industrial Internet of Things(IIoT) provable security
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An Updated Lagrangian Particle Hydrodynamics (ULPH)-NOSBPD Coupling Approach forModeling Fluid-Structure Interaction Problem
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作者 Zhen Wang Junsong Xiong +3 位作者 Shaofan Li Xin Lai xiang liu Lisheng liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期491-523,共33页
A fluid-structure interaction approach is proposed in this paper based onNon-Ordinary State-Based Peridynamics(NOSB-PD)and Updated Lagrangian Particle Hydrodynamics(ULPH)to simulate the fluid-structure interaction pro... A fluid-structure interaction approach is proposed in this paper based onNon-Ordinary State-Based Peridynamics(NOSB-PD)and Updated Lagrangian Particle Hydrodynamics(ULPH)to simulate the fluid-structure interaction problem with large geometric deformation and material failure and solve the fluid-structure interaction problem of Newtonian fluid.In the coupled framework,the NOSB-PD theory describes the deformation and fracture of the solid material structure.ULPH is applied to describe the flow of Newtonian fluids due to its advantages in computational accuracy.The framework utilizes the advantages of NOSB-PD theory for solving discontinuous problems and ULPH theory for solving fluid problems,with good computational stability and robustness.A fluidstructure coupling algorithm using pressure as the transmission medium is established to deal with the fluidstructure interface.The dynamic model of solid structure and the PD-ULPH fluid-structure interaction model involving large deformation are verified by numerical simulations.The results agree with the analytical solution,the available experimental data,and other numerical results.Thus,the accuracy and effectiveness of the proposed method in solving the fluid-structure interaction problem are demonstrated.The fluid-structure interactionmodel based on ULPH and NOSB-PD established in this paper provides a new idea for the numerical solution of fluidstructure interaction and a promising approach for engineering design and experimental prediction. 展开更多
关键词 Fluid-structure interaction(FSI) updated lagrangian particle hydrodynamics PERIDYNAMICS meshfree method
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Updated Lagrangian Particle Hydrodynamics (ULPH)Modeling of Natural Convection Problems
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作者 Junsong Xiong Zhen Wang +3 位作者 Shaofan Li Xin Lai Lisheng liu xiang liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期151-169,共19页
Natural convection is a heat transfer mechanism driven by temperature or density differences,leading to fluid motion without external influence.It occurs in various natural and engineering phenomena,influencing heat t... Natural convection is a heat transfer mechanism driven by temperature or density differences,leading to fluid motion without external influence.It occurs in various natural and engineering phenomena,influencing heat transfer,climate,and fluid mixing in industrial processes.This work aims to use the Updated Lagrangian Particle Hydrodynamics(ULPH)theory to address natural convection problems.The Navier-Stokes equation is discretized using second-order nonlocal differential operators,allowing a direct solution of the Laplace operator for temperature in the energy equation.Various numerical simulations,including cases such as natural convection in square cavities and two concentric cylinders,were conducted to validate the reliability of the model.The results demonstrate that the proposed model exhibits excellent accuracy and performance,providing a promising and effective numerical approach for natural convection problems. 展开更多
关键词 Updated Lagrangian particle hydrodynamics(ULPH) natural convection meshless methods higher order Laplacian model
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Advances in endoscopic diagnosis and management of colorectal cancer
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作者 Shi-Wei Li xiang liu Si-Yu Sun 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第10期4045-4051,共7页
Colorectal cancer(CRC)is a leading global health concern,and early identification and precise prognosis play a vital role in enhancing patient results.Endoscopy is a minimally invasive imaging technique that is crucia... Colorectal cancer(CRC)is a leading global health concern,and early identification and precise prognosis play a vital role in enhancing patient results.Endoscopy is a minimally invasive imaging technique that is crucial for the screening,diagnosis,and treatment of CRC.This editorial discusses the importance of advances in endoscopic techniques,the integration of artificial intelligence,and the potential of novel technologies in enhancing the diagnosis and management of CRC. 展开更多
关键词 Colorectal cancer Endoscopic diagnosis Endoscopic management Artificial intelligence Endoscopic devices
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Assessment of the Influence of Tunnel Settlement on Operational Performance of Subway Vehicles
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作者 Gang Niu Guangwei Zhang +2 位作者 Zhaoyang Jin Wei Zhang xiang liu 《Structural Durability & Health Monitoring》 EI 2024年第1期55-71,共17页
In the realm of subway shield tunnel operations,the impact of tunnel settlement on the operational performance of subway vehicles is a crucial concern.This study introduces an advanced analytical model to investigate ... In the realm of subway shield tunnel operations,the impact of tunnel settlement on the operational performance of subway vehicles is a crucial concern.This study introduces an advanced analytical model to investigate rail geometric deformations caused by settlement within a vehicle-track-tunnel coupled system.The model integrates the geometric deformations of the track,attributed to settlement,as track irregularities.A novel“cyclic model”algorithm was employed to enhance computational efficiency without compromising on precision,a claim that was rigorously validated.The model’s capability extends to analyzing the time-history responses of vehicles traversing settlement-affected areas.The research primarily focuses on how settlement wavelength,amplitude,and vehicle speed influence operational performance.Key findings indicate that an increase in settlement wavelength can improve vehicle performance,whereas a rise in amplitude can degrade it.The study also establishes settlement thresholds,based on vehicle operation comfort and safety.These insights are pivotal for maintaining and enhancing the safety and efficiency of subway systems,providing a valuable framework for urban infrastructure management and long-term maintenance strategies in metropolitan transit systems. 展开更多
关键词 SETTLEMENT running performance subway tunnel dynamic analysis track irregularity THRESHOLD
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The Influence of Acid on the RockMechanical Characteristics of Deep Shale in theWujiaping Formation
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作者 Hao Zhang Yan Zhang +2 位作者 Wei liu Ximin Zhang xiang liu 《Energy Engineering》 EI 2024年第1期27-42,共16页
The microscopic characteristics and mechanical properties of rocks change after the action of acid on deep shale,which affects the fracturing effect.Accordingly,we designed and conducted indoor experiments related to ... The microscopic characteristics and mechanical properties of rocks change after the action of acid on deep shale,which affects the fracturing effect.Accordingly,we designed and conducted indoor experiments related to the changes in macro and microscopic characteristics after the interaction of acid with the shale of Wujiaping Formation,based on which the characteristic law of fracture volume modification after acid fracturing was studied using numerical simulation.The results demonstrate that the pores and fractures are enlarged and the structure is significantly loosened after the acid immersion.And a 15%concentration of hydrochloric acid can effectively dissolve shale.Furthermore,the degree of acid-etching reaction is highly variable because of the different carbonate content,which reveals the strong inhomogeneity of the shale system in the Wujiaping Group reservoir section.After the acid interacted with the shale rock samples,the triaxial compressive strength,elastic modulus,and Poisson’s ratio of shale decreased.Moreover,the evaluation of the effect after acid fracturing simulated by fracturing software revealed that the smaller the value of elastic modulus in shale-based reservoirs,the more favorable the fracture volume modification.This discovery not only provides a theoretical basis for the expansion and extension patterns of acid-fracturing in carbonaceous shale formations but also offers research methods and theoretical insights for the fundamental exploration of other deep-seated oil and gas resources. 展开更多
关键词 SHALE acid fracturing macro characteristics microscopic characteristics mechanical properties
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Reproducibility study of intravoxel incoherent motion and apparent diffusion coefficient parameters in normal pancreas
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作者 xiang liu Yi-Feng Wang +6 位作者 Xiao-Hui Qi Zhi-Lei Zhang Jiang-Yang Pan Xue-Li Fan Yu Du Ying-Min Zhai Qi Wang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第7期2031-2039,共9页
BACKGROUND The consistency of pancreatic apparent diffusion coefficient(ADC)values and intravoxel incoherent motion(IVIM)parameter values across different magnetic resonance imaging(MRI)devices significantly impacts t... BACKGROUND The consistency of pancreatic apparent diffusion coefficient(ADC)values and intravoxel incoherent motion(IVIM)parameter values across different magnetic resonance imaging(MRI)devices significantly impacts the patient’s diagnosis and treatment.AIM To explore consistency in image quality,ADC values,and IVIM parameter values among different MRI devices in pancreatic examinations.METHODS This retrospective study was approved by the local ethics committee,and informed consent was obtained from all participants.In total,22 healthy volunteers(10 males and 12 females)aged 24-61 years(mean,28.9±2.3 years)underwent pancreatic diffusion-weighted imaging using 3.0T MRI equipment from three vendors.Two independent observers subjectively scored image quality and measured the pancreas’s overall ADC values and signal-to-noise ratios(SNRs).Subsequently,regions of interest(ROIs)were delineated for the IVIM parameters(true diffusion coefficient,pseudo-diffusion coefficient,and perfusion fraction)using post-processing software.These ROIs were on the head,body,and tail of the pancrease.The subjective image ratings were assessed using the kappa consistency test.Intraclass correlation coefficients(ICCs)and mixed linear models were used to evaluate each device’s quantitative parameter values.Finally,a pairwise analysis of IVIM parameter values across each device was performed using Bland-Altman plots.RESULTS The Kappa value for the subjective ratings of the different observers was 0.776(P<0.05).The ICC values for interobserver and intra-observer agreements for the quantitative parameters were 0.803[95% confidence interval(CI):0.684-0.880]and 0.883(95%CI:0.760-0.945),respectively(P<0.05).The ICCs for the SNR between different devices was comparable(P>0.05),and the ICCs for the ADC values from different devices were 0.870,0.707,and 0.808,respectively(P<0.05).Notably,only a few statistically significant inter-device agreements were observed for different IVIM parameters,and among those,the ICC values were generally low.The mixed linear model results indicated differences(P<0.05)in the f-value for the pancreas head,D-value for the pancreas body,and D-value for the pancreas tail obtained using different MRI machines.The Bland-Altman plots showed significant variability at some data points.CONCLUSION ADC values are consistent among different devices,but the IVIM parameters’repeatability is moderate.Therefore,the variability in the IVIM parameter values may be associated with using different MRI machines.Thus,caution should be exercised when using IVIM parameter values to assess the pancreas. 展开更多
关键词 Intravoxel incoherent motion PANCREAS Image quality Consistency test
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Temperature field calculation of rail flash welding
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作者 Rui Xu Min Zhang +6 位作者 Zhenkun Gao Guo Zhao Wei Ding Shouming Wang Peng Zhang xiang liu Jingjing Li 《High-Speed Railway》 2024年第2期116-121,共6页
The forging stage of rail flash welding has a decisive influence on joint strength,and the study of the temperature distribution in the process has an important role in further improving joint strength.In this paper,t... The forging stage of rail flash welding has a decisive influence on joint strength,and the study of the temperature distribution in the process has an important role in further improving joint strength.In this paper,three calculation methods for the temperature field are given.First,the finite element model of the temperature field before forging rail flash welding is established by using the transient heat module of Ansys software and verified by infrared temperature measurement.Second,the temperature distribution of different parts of the rail before flash welding is obtained by using infrared thermal imaging equipment.Third,Matlab software is used to calculate the temperature of the non-measured part.Finally,the temperature distribution function along the rail axis is fitted through the temperature measurement data.The temperature distribution before the top forging of the rail flash welding can be used to analyze the joint and heat-affected zone organization and properties effectively and to guide the parameter setting and industrial production. 展开更多
关键词 Flash welding Temperature field Joint strength Software calculation
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Adaptive scale model reconstruction for radio synthesis imaging 被引量:2
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作者 Li Zhang Li-Gong Mi +6 位作者 Long Xu Ming Zhang Dan-Yang Li xiang liu Feng Wang Yi-Fan Xiao Zhong-Zu Wu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第3期117-127,共11页
A sky model from CLEAN deconvolution is a particularly effective high dynamic range reconstruction in radio astronomy,which can effectively model the sky and remove the sidelobes of the point spread function(PSF)cause... A sky model from CLEAN deconvolution is a particularly effective high dynamic range reconstruction in radio astronomy,which can effectively model the sky and remove the sidelobes of the point spread function(PSF)caused by incomplete sampling in the spatial frequency domain.Compared to scale-free and multi-scale sky models,adaptive-scale sky modeling,which can model both compact and diffuse features,has been proven to have better sky modeling capabilities in narrowband simulated data,especially for large-scale features in high-sensitivity observations which are exactly one of the challenges of data processing for the Square Kilometre Array(SKA).However,adaptive scale CLEAN algorithms have not been verified by real observation data and allow negative components in the model.In this paper,we propose an adaptive scale model algorithm with non-negative constraint and wideband imaging capacities,and it is applied to simulated SKA data and real observation data from the Karl G.Jansky Very Large Array(JVLA),an SKA precursor.Experiments show that the new algorithm can reconstruct more physical models with rich details.This work is a step forward for future SKA image reconstruction and developing SKA imaging pipelines. 展开更多
关键词 methods:data analysis techniques:image processing techniques:interferometric
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结直肠癌术后辅助卡培他滨为基础化疗方案的临床疗效及相关药物基因组学分析 被引量:6
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作者 刘世举 张慧俭 +4 位作者 王金榜 杨会举 张新春 刘翔 刘佃温 《中国肿瘤临床》 CAS CSCD 北大核心 2018年第17期889-893,共5页
目的:本研究旨在探讨结直肠癌(colorectal cancer,CRC)术后辅助卡培他滨为基础化疗方案的疗效及相关药物基因组学分析。方法:回顾性分析2010年1月至2017年6月河南中医药大学第三附属医院收治术后接受辅助化疗的CRC患者215例。收集外周... 目的:本研究旨在探讨结直肠癌(colorectal cancer,CRC)术后辅助卡培他滨为基础化疗方案的疗效及相关药物基因组学分析。方法:回顾性分析2010年1月至2017年6月河南中医药大学第三附属医院收治术后接受辅助化疗的CRC患者215例。收集外周血提取DNA用来进行胞苷脱氨酶(cytidine deaminase,CDD)多态性位点基因分型。另外,收集85例患者的化疗前外周血单核细胞(peripheral blood mononuclear cell,PBMC)提取RNA对CDD的m RNA表达水平进行测定。结果:215例患者具有良好的疗效。药物基因组学分析方面,发现CDD基因启动子区域的多态性位点-451C>A和疗效相关,该位点GA/AA和GG基因型患者的3年无疾病生存率(disease-free survival,DFS)分别为81.03%和62.42%,差异具有统计学意义(P=0.002)。两种基因型患者的5年总生存率(overall survival,OS)分别为72.41%和53.50%,差异具有统计学意义(P=0.016)。在85例患者外周血单核细胞的mRNA表达分析中发现,携带A等位基因的患者相对于GG型患者,外周血单核细胞中CDD的mRNA表达明显较高,差异具有统计学意义(P<0.001)。结论:卡培他滨为基础的化疗方案具有良好的治疗效果。CDD基因-451C>A位点可能通过影响该基因m RNA的表达使CRC患者从卡培他滨的治疗当中获益。 展开更多
关键词 结直肠癌 胞苷脱氨酶 多态性 疗效
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XRD对ZnO薄膜生长条件和退火工艺的优化 被引量:3
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作者 王金忠 闫玮 +9 位作者 王新强 殷景志 姜秀英 杨树人 杜国同 高鼎三 xiang liu Hui Cao Junying Xu R.P.H.Chang 《半导体光电》 CAS CSCD 北大核心 2001年第3期169-172,共4页
利用等离子体MOCVD设备在 (0 0 1)蓝宝石上生长了ZnO薄膜。通过对在不同条件下生长的薄膜样品X射线衍射的测量和分析 ,优化了薄膜的生长条件 ,长出了半高宽仅为 0 .15°的单一取向的高质量ZnO薄膜 ,并发现生长过程中多次退火或掺氮... 利用等离子体MOCVD设备在 (0 0 1)蓝宝石上生长了ZnO薄膜。通过对在不同条件下生长的薄膜样品X射线衍射的测量和分析 ,优化了薄膜的生长条件 ,长出了半高宽仅为 0 .15°的单一取向的高质量ZnO薄膜 ,并发现生长过程中多次退火或掺氮在薄膜中引入了张应力 ,而生长结束后一次退火却引入了压应力。 展开更多
关键词 等离子体MOCVD X射线衍射 氧化锌薄膜 退火工艺 生长条件
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工作应激与健康体检人群心电图异常表现的相关性分析 被引量:14
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作者 刘翔 赵君 洪艳玲 《中国现代医学杂志》 CAS 北大核心 2017年第28期102-105,共4页
目的探讨工作应激对健康体检人群心电图表现的影响。方法选取2015年6月-2016年1月在泸州市人民医院接受健康体检的人群282例。依据职业紧张压力量表OSI评分分为工作应激高水平组(≤15分)和工作应激低水平组(>15分),比较两组受检者的... 目的探讨工作应激对健康体检人群心电图表现的影响。方法选取2015年6月-2016年1月在泸州市人民医院接受健康体检的人群282例。依据职业紧张压力量表OSI评分分为工作应激高水平组(≤15分)和工作应激低水平组(>15分),比较两组受检者的心电图异常情况。结果健康体检282例,心电图异常57例,其中ST-T段改变21例,Q-Tc间期延长15例,P-R间期延长12例,传导阻滞9例,窦性心律不齐6例,心律失常6例,心电轴左偏3例,心房颤动3例,早搏3例,其他9例。工作应激高水平组159例,心电图异常45例(28.30%),工作应激低水平组123例,心电图异常12例(9.76%)。工作应激高水平组≤40岁、41~59岁、≥60岁人群心电图异常率分别为10.00%、30.00%和38.46%;工作应激低水平组≤40岁、41~59岁、≥60岁人群心电图异常率分别为7.69%、5.56%和20.00%。两组受检者41~59岁、≥60岁人群心电图异常率的比较,差异有统计学意义(P<0.05)。年龄、工种、工作应激是影响健康体检人群心电图表现的危险因素。结论工作应激是引起以ST-T段改变、Q-Tc间期延长为主的心电图异常改变的危险因素,应激水平越高,心电图异常率随之增加,且对中老年人群影响更大。 展开更多
关键词 工作应激 心电图 年龄 异常
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