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Effect of vehicle-bridge interaction on nonlinear seismic performance of bridge under strong earthquakes
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作者 ke chen Zhibin Jin Haoyuan Yang 《High-Speed Railway》 2025年第3期215-228,共14页
Railway bridges are continuously loaded by railway trains;therefore, it is important to understand the nonlinear seismic response of the Vehicle-Bridge Interaction (VBI) system under strong earthquakes. For this purpo... Railway bridges are continuously loaded by railway trains;therefore, it is important to understand the nonlinear seismic response of the Vehicle-Bridge Interaction (VBI) system under strong earthquakes. For this purpose, the nonlinear behavior of the pier was introduced into the in-house VBI solvers. The nonlinear the seismic response of the VBI system was comprehensively evaluated using this model, and the effect of the vehicle dynamics on seismic performance of the bridge was identified. It was found that the seismic responses of most simply-supported bridges were reduced in the presence of railway trains due to the out-of-phase motion of the vehicle-bridge system. Meanwhile, the nonlinear behavior of the pier can reduce the vehicle’s seismic responses. Therefore, ignoring the nonlinear behavior of the pier during strong earthquakes can significantly overestimate the seismic response of the vehicle. 展开更多
关键词 Bridge nonlinear behavior Vehicle dynamics effect Seismnic safety Vehicle-bridge interaction Pier height
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MouseVenue3D:A Markerless Three-Dimension Behavioral Tracking System for Matching Two-Photon Brain Imaging in Free-Moving Mice 被引量:3
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作者 Yaning Han Kang Huang +8 位作者 ke chen Hongli Pan Furong Ju Yueyue Long Gao Gao Runlong Wu Aimin Wang Liping Wang Pengfei Wei 《Neuroscience Bulletin》 SCIE CAS CSCD 2022年第3期303-317,共15页
Understanding the connection between brain and behavior in animals requires precise monitoring of their behaviors in three-dimensional(3-D)space.However,there is no available three-dimensional behavior capture system ... Understanding the connection between brain and behavior in animals requires precise monitoring of their behaviors in three-dimensional(3-D)space.However,there is no available three-dimensional behavior capture system that focuses on rodents.Here,we present MouseVenue3D,an automated and low-cost system for the efficient capture of 3-D skeleton trajectories in markerless rodents.We improved the most time-consuming step in 3-D behavior capturing by developing an automatic calibration module.Then,we validated this process in behavior recognition tasks,and showed that 3-D behavioral data achieved higher accuracy than 2-D data.Subsequently,MouseVenue3D was combined with fast high-resolution miniature two-photon microscopy for synchronous neural recording and behavioral tracking in the freely-moving mouse.Finally,we successfully decoded spontaneous neuronal activity from the 3-D behavior of mice.Our findings reveal that subtle,spontaneous behavior modules are strongly correlated with spontaneous neuronal activity patterns. 展开更多
关键词 Computational neuroethology Behavioral and neural recording 3-D pose estimation Multi-view cameras Automatic calibration
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Community Structures of Phytoplankton with Emphasis on Toxic Cyanobacteria in an Ohio Inland Lake during Bloom Season 被引量:3
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作者 ke chen Joel Allen Jingrang Lu 《Journal of Water Resource and Protection》 2017年第11期1299-1318,共20页
The community structures of phytoplankton are important factors and indicators of lake water quality. Harmful algal blooms severely impact water supply, recreational activities and wildlife habitat. This study aimed t... The community structures of phytoplankton are important factors and indicators of lake water quality. Harmful algal blooms severely impact water supply, recreational activities and wildlife habitat. This study aimed to examine the phytoplankton composition and variations using microscopy, and identify harmful Cyanobacteria in weekly samples taken from four sites at Harsha Lake in southwest Ohio. Over the course of the summer in 2015, the phytoplankton of Harsha Lake consisted mainly of 13 taxa belonging to Bacillariophyta, Chlorophyta, Cryptophyta, Cyanobacteria, Dinophyta and Euglenophyta. Their significant successions started with Bacillariophyta and/or Chlorophyta, then bloomed with Cyanobacteria and ended with Chlorophyta and/or Dinophyta. Cyanobacteria members: Microcystis, Planktothrix, Dolichospermum, Aphanizomenon, Cylindrospermopsis, and Oscillatoria from the Cyanophyceae were identified to be dominant genera. These organisms varied spatially and temporally in similar patterns along with the variations of nutrients and formed the summer bloom with the total biomasses ranging from 0.01 to 114.89 mg L-1 with mean of 22.88 mg L-1. M. aeruginosa and P. rubescens were revealed as the microcystin producers, while A. circinalis and Aphanizomenon sp. were identified as a saxitoxin producer through cloning and sequencing PCR products of mcyA, mcyE and sxtA genes. The biomasses of phytoplankton, Cyanobacteria and Microcystis were positively correlated to nutrients, especially to total nitrogen. The total ELISA measurement for microcystin positively correlated with Cyanobacteria (R2 = 0.66, P Microcystis (R2 = 0.64, P 2 = 0.59, P < 0.0001). The basic information on the occurrence and biomasses of Cyanobacteria and total phytoplankton, and the analysis for toxic species, which were the first report for the inland water in Ohio, USA, will document the succession patterns of phytoplankton and toxin production over a season and provide data to predict risk occurrence to both human and ecological factors. 展开更多
关键词 PHYTOPLANKTON CYANOBACTERIA BLOOM TOXIN PRODUCER Lake
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Efficient polysulfide blocker from conductive niobium nitride@graphene for Li-S batteries 被引量:1
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作者 Huifa Shi Zhenhua Sun +8 位作者 Wei Lv Shujie Xiao Huicong Yang Ying Shi ke chen Shaogang Wang Bingsen Zhang Quan-Hong Yang Feng Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第6期135-141,I0006,共8页
Lithium sulfur batteries are one of the most promising alternative electrochemical systems,but their practical applications are largely hindered by the serious shuttling problems and sluggish redox kinetics.Here,the c... Lithium sulfur batteries are one of the most promising alternative electrochemical systems,but their practical applications are largely hindered by the serious shuttling problems and sluggish redox kinetics.Here,the conductive and polar niobium nitride(NbN)is in-situ introduced onto graphene with ultrasmall size and high dispersion,and their composite is used to construct an efficient lithium polysulfide blocking layer.The graphene helps to construct highly conductive pathways,and niobium nitride serves as the sulfiphilic sites to chemically adsorb the migrating lithium polysulfides and catalyze their redox conversion.Hence,the cells with the Nb N/G interlayers exhibit a long cycle life with a lower capacity decay of 0.096%/cycle at 1 C for 300 cycles and high rate capability of 937 m Ah g^-1 at 2 C.Further coupling with a sulfur/carbon nanofiber electrode,the cell with an ultra-high sulfur loading of 10.8 mg cm^-2 delivers an areal capacity of 12.5 m Ah cm^-2 at 0.1 C. 展开更多
关键词 Lithium-sulfur BATTERIES NIOBIUM NITRIDE Chemical adsorption Catalytic effect High loading
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A Two-Party Password-Authenticated Key Exchange Protocol with Verifier
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作者 Shunbo Xiang Bing Xu ke chen 《Journal of Computer and Communications》 2021年第4期102-109,共8页
To tackle with the security lack in the password-authenticated key exchange protocol, this paper proposes a two-party password-authenticated key exchange protocol based on a verifier. In the proposed protocol, a user ... To tackle with the security lack in the password-authenticated key exchange protocol, this paper proposes a two-party password-authenticated key exchange protocol based on a verifier. In the proposed protocol, a user stores his password in plaintext, and the server stores a verifier for the user’s password, using DL difficult problem and DH difficult problem, through the session between user and server to establish a session key. The security discussion result shows that the proposed protocol provides forward secrecy, and can effectively defend against server compromising fake attacks, dictionary attacks and middleman attacks. Protocol efficiency comparisons reveal our protocol is more reasonable. 展开更多
关键词 VERIFIER Password-Authenticated Key Exchange Fake Attack Dictionary Attack Session Key
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Interfacial intermetallic compound layer in friction stir welded Mg/Al joints:Relationship between thickness and the welding temperature history 被引量:1
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作者 Xuesong Fu ke chen +3 位作者 Qingsong Zhang Nannan chen Min Wang Xueming Hu 《Journal of Magnesium and Alloys》 2025年第6期2540-2553,共14页
Thickness of the intermetallic compounds(IMC)layer at the interface has a significant effect on the mechanical properties of Mg/Al dissimilar joints.However,the thickness of IMC layer can be only obtained by metallurg... Thickness of the intermetallic compounds(IMC)layer at the interface has a significant effect on the mechanical properties of Mg/Al dissimilar joints.However,the thickness of IMC layer can be only obtained by metallurgical microscopy,which is destructive and has to break down the weld.Therefore,it is crucial to find a reliable approach that can non-destructively predict the thickness of IMC layer in practical application.In the current study,Mg alloy and Al alloy were friction stir butt welded(FSW)under different tool rotation speeds(TRS)to obtain different thicknesses of IMC layers.As the TRS increased from 400 rpm to 1000 rpm,thickness of the IMC layer increased from 0.4μm to 1.3μm,the peak welding temperatures increased from 259℃to 402℃,and the Z-axis downforces decreased from10.5 kN to 3.2 k N during welding process.Higher TRS would generally induce higher welding heat input,which promotes the growth of the IMC layer and the softening of base materials.The IMC layer formed through solid-state diffusion and transformation instead of eutectic reaction according to the welding temperature history and interfacial microstructure,and its evolution process was clearly observed by plan view.In order to incorporate the effect of dramatic change of welding temperature which is the characteristic feature of FSW,Psd Voigt function was used to fit the welding temperature histories.A new prediction formula was then established to predict thicknesses of IMC layers with considering sharp welding temperature change.Predicted thicknesses gave good agreement with measured thicknesses obtained experimentally under different welding parameters,which confirmed the accuracy and reliability of the new prediction formula.Based on this prediction formula,the time period of temperature higher than 200℃during welding was found critical for the thickening of interfacial IMC layers. 展开更多
关键词 Friction stir welding Mg/Al dissimilar joint Intermetallic compound Welding temperature Interface
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AdaptForever:Elastic and Mutual Learning for Continuous NLP Task Mastery
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作者 ke chen cheng Peng +4 位作者 Xinyang He Jiakang Sun Xu Liu Xiaolin Qin Yong Zhong 《Computers, Materials & Continua》 2025年第3期4003-4019,共17页
In natural language processing(NLP),managing multiple downstream tasks through fine-tuning pre-trained models often requires maintaining separate task-specific models,leading to practical inefficiencies.To address thi... In natural language processing(NLP),managing multiple downstream tasks through fine-tuning pre-trained models often requires maintaining separate task-specific models,leading to practical inefficiencies.To address this challenge,we introduce AdaptForever,a novel approach that enables continuous mastery of NLP tasks through the integration of elastic and mutual learning strategies with a stochastic expert mechanism.Our method freezes the pre-trained model weights while incorporating adapters enhanced with mutual learning capabilities,facilitating effective knowledge transfer from previous tasks to new ones.By combining Elastic Weight Consolidation(EWC)for knowledge preservation with specialized regularization terms,AdaptForever successfully maintains performance on earlier tasks while acquiring new capabilities.Experimental results demonstrate that AdaptForever achieves superior performance across a continuous sequence of NLP tasks compared to existing parameter-efficient methods,while effectively preventing catastrophic forgetting and enabling positive knowledge transfer between tasks. 展开更多
关键词 Adapter-tuning large language model pre-trained language model parameter-efficient fine tuning continue learning mutual learning mixture of expert
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Prediction Model of Deformation Resistance and Rolling Force of ESP Production Line Based on the Temperature Gradient
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作者 Panpan Li Wei Li +3 位作者 Yaxing Liu ke chen Tao Wang Qingxue Huang 《Chinese Journal of Mechanical Engineering》 2025年第6期517-533,共17页
The existence of significant core-surface temperature differences in the strips during the rolling process in the endless strip production line leads to low accuracy in calculating the hot rolling force model assuming... The existence of significant core-surface temperature differences in the strips during the rolling process in the endless strip production line leads to low accuracy in calculating the hot rolling force model assuming uniform temperature.This paper divides the deformation zone of strips into cells along the thick and the roll direction considering the non-uniform distribution of temperature,strain,strain rate in the thick direction cell of the strips,and the change of deformation resistance in the roll direction cell of strips.Then this study separately establishes the temperature matrix,strain matrix,and strain rate matrix on the"thick direction-roll direction"of strips,and constructs a deformation resistance calculation model based on the matrix cell.Further,a model for calculating rolling forces applicable to this production line was derived based on the Orowan equilibrium differential equation.The accuracy of the rolling force model and temperature variation patterns of the thick-directional units of the rolled parts during rolling were verified by hot rolling simulation experiments on a strip with an embedded block of the same material.Take an endless strip production line in China as an example to carry out simulation calculations of Q235 material.The results show that the average calculation error of the model built in this paper is 4.4%.Simulation and error analysis of multiple materials and multiple specifications of strip steel show that the prediction accuracy of the model in this paper meets the requirements of the production line,which provides theoretical support for the formulation and optimization of the rolling process of this production line. 展开更多
关键词 Endless strip production Temperaturefield STRAIN Strain rate Deformation resistance Rolling force
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Robust interfacial bonding achieved via phase separation induced by enhanced Al diffusion during AZ31/high-entropy alloy friction stir welding
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作者 Gaohui Li Haining Yao +4 位作者 Boyuan Fu ke chen Katsuyoshi Kondoh Nannan chen Min Wang 《Journal of Magnesium and Alloys》 2025年第3期1012-1019,共8页
Welding high-entropy alloy(HEA)to Mg alloy has gained increasing attention for multi-metal structure design,while intrinsic sluggish diffusion kinetics of HEA confines diffusion-controlled interfacial reactions and mak... Welding high-entropy alloy(HEA)to Mg alloy has gained increasing attention for multi-metal structure design,while intrinsic sluggish diffusion kinetics of HEA confines diffusion-controlled interfacial reactions and makes it challenging to establish robust metallurgical bonding.This study investigated welding of FeCoCrNiMn HEA to commercial AZ31 as a model combination to pioneer thisfield.Interfacial phase separation phenomenon was observed,with the diffusion accelerated by in-situ engineering a submicron-scale thick(∼400–500 nm)HEA nearby the interface into nanocrystalline-structure during friction stir welding.Abundant grain boundaries generated in this nanocrystalline-interlayer serve as diffusion short-circuits and energetically preferred nucleation-sites,which promoted Al in AZ31 to diffuse into HEA and triggered quick separation into body-centered cubic AlNi-type and tetragonal FeCr-type intermetallics.HEA and AZ31 were thus metallurgically bonded by these interfacial intermetallics.The joint shows exceptional strength in tensile lap-shear testing with fracture largely occurred within AZ31 rather than right along interface as commonly reported previously for dissimilar joints. 展开更多
关键词 High-entropy alloy Mg alloy Friction stir welding DIFFUSION Phase separation
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GEN1 regulates cell proliferation,migration,apoptosis and ferroptosis in gastric cancer
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作者 Qi Zhang Zu-Guo Yuan +1 位作者 Kai-Feng Zheng ke chen 《World Journal of Gastrointestinal Oncology》 2025年第8期344-357,共14页
BACKGROUNDGastric cancer(GC)has a high prevalence and mortality overall.GEN1 is associatedwith abnormal centrosome amplification,DNA damage and increasedapoptosis.To date,little is known about the function and mechani... BACKGROUNDGastric cancer(GC)has a high prevalence and mortality overall.GEN1 is associatedwith abnormal centrosome amplification,DNA damage and increasedapoptosis.To date,little is known about the function and mechanism of GEN1 inGC.AIMTo explore the cellular processes associated with GC will help to elucidate themechanism of the occurrence and development of GC and discover potentialtherapeutic targets.METHODSThe detection of GEN1 expression at mRNA and protein levels was done by realtimequantitative polymerase chain reaction and western blotting.The function ofGEN1 was verified by loss-of-function experiments in AGS cells.The genes coexpressedwith GEN1 were searched from the stomach adenocarcinomas(STAD)data in The Cancer Genome Atlas database.Kyoto Encyclopedia of Genes andGenomes(KEGG)enrichment analysis of the genes co-expressed with GEN1 tofurther identify the pathways involved in GEN1.Rescue experiments usingferroptosis inhibitor ferrostatin-1 and chemotherapeutic sensitivity assays withcisplatin were also performed.RESULTSSignificant up-regulation of GEN1 was observed in GC cell lines AGS and MGC-803.Inhibition of GEN1 induced cell apoptosis and decreased cell proliferation,cycle progression,migration in AGS cells.There were 264 genes co-expressedwith GEN1 in STAD cohort(r>0.4,P<0.001).KEGG enrichment analysis showed that GEN1 might be associated with the cell cycle,Fanconi anemia pathway,homologous recombination,oocytemeiosis and cellular senescence in GC.Furthermore,CCNA2,CCNB1,CCNB2,cyclin-dependent kinase(CDK)1,CDK2 and polo-like kinase 1 protein levels were lower in GEN1-knockdown AGS cells,manifesting that GEN1 wasassociated with the cell cycle pathway in AGS cells.Downregulation of GEN1 decreased adenosine triphosphatecontent and elevated reactive oxygen species in AGS cells,suggesting that GEN1 silencing led to mitochondrialdysfunction in AGS cells.In addition,GEN1 silencing caused an overt decrease in FTH1 and GPX4 protein levelsand a significant elevation in ACSL4 protein levels,implying that GEN1 silencing promoted AGS cell ferroptosis.Treatment with ferrostatin-1 rescued cell viability loss induced by GEN1 knockdown,confirming ferroptosis as akey death mechanism.Additionally,GEN1-deficient AGS cells showed enhanced sensitivity to cisplatin,with asignificantly reduced half-maximal inhibitory concentration compared to control cells.CONCLUSIONGEN1 promotes GC cell proliferation and migration while suppressing apoptosis and ferroptosis.Targeting GEN1not only disrupts mitochondrial function and cell cycle progression but also sensitizes GC cells to ferroptosis andchemotherapy.These findings highlight GEN1 as a potential therapeutic target for enhancing treatment efficacy ingastric cancer. 展开更多
关键词 Gastric cancer GEN1 Cell cycle Ferroptosis The Cancer Genome Atlas database
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UniTrans:Unified Parameter-Efficient Transfer Learning and Multimodal Alignment for Large Multimodal Foundation Model
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作者 Jiakang Sun ke chen +3 位作者 Xinyang He Xu Liu ke Li cheng Peng 《Computers, Materials & Continua》 2025年第4期219-238,共20页
With the advancements in parameter-efficient transfer learning techniques,it has become feasible to leverage large pre-trained language models for downstream tasks under low-cost and low-resource conditions.However,ap... With the advancements in parameter-efficient transfer learning techniques,it has become feasible to leverage large pre-trained language models for downstream tasks under low-cost and low-resource conditions.However,applying this technique to multimodal knowledge transfer introduces a significant challenge:ensuring alignment across modalities while minimizing the number of additional parameters required for downstream task adaptation.This paper introduces UniTrans,a framework aimed at facilitating efficient knowledge transfer across multiple modalities.UniTrans leverages Vector-based Cross-modal Random Matrix Adaptation to enable fine-tuning with minimal parameter overhead.To further enhance modality alignment,we introduce two key components:the Multimodal Consistency Alignment Module and the Query-Augmentation Side Network,specifically optimized for scenarios with extremely limited trainable parameters.Extensive evaluations on various cross-modal downstream tasks demonstrate that our approach surpasses state-of-the-art methods while using just 5%of their trainable parameters.Additionally,it achieves superior performance compared to fully fine-tuned models on certain benchmarks. 展开更多
关键词 Parameter-efficient transfer learning multimodal alignment image captioning image-text retrieval visual question answering
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Clinical significance of Ki-67 in patients with lung adenocarcinoma in situ complicated by type 2 diabetes
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作者 ke chen Ge Wang +2 位作者 Jing-cheng Hu Ying-Yi Zhou Hai-Tao Ma 《World Journal of Diabetes》 2025年第2期114-122,共9页
BACKGROUND The increasing number of type 2 diabetes mellitus(T2DM)patients leads to higher rates of morbidity and mortality related to lung cancer.AIM To investigate the utility of the proliferating cell nuclear antig... BACKGROUND The increasing number of type 2 diabetes mellitus(T2DM)patients leads to higher rates of morbidity and mortality related to lung cancer.AIM To investigate the utility of the proliferating cell nuclear antigen Ki-67 in patients with lung adenocarcinoma in situ(AIS)complicated by T2DM.METHODS One hundred patients with AIS and T2DM(group A),100 patients with AIS alone(group B),and 60 patients with benign lung lesions(group C)admitted to the Department of Thoracic Surgery and Endocrinology of the First Affiliated Hospital of Soochow University from November 2021 to December 2022 were enrolled.Ki-67 expression was compared among the groups.RESULTS Group A had significantly higher levels of fasting plasma glucose(FPG),total cholesterol(TC),total triglyceride,low-density lipoprotein cholesterol,glycosylated hemoglobin(HbA1c),and insulin than groups B and C(P<0.01).Meanwhile,group B had higher insulin levels than group C(P<0.01).Group A exhibited a significantly higher average Ki-67 positivity rate than group B(P<0.01).The Ki-67 positivity rate in group A was 86.87%,while the positivity rate in group B was 77%.Ki-67 was positively correlated with FPG(P<0.01)and HbA1c levels(P<0.01).Ki-67,FBG,insulin,HbA1c,high-density lipoprotein cholesterol and TC were independent factors for patients with AIS complicated by T2DM.Chen K et al.Ki67 in patients with AIS complicated by T2DM WJD https://www.wjgnet.com 2 February 15,2025 Volume 16 Issue 2 CONCLUSION Ki-67 expression was higher in patients with AIS complicated by T2DM than in patients with AIS alone.Therefore,detecting the Ki-67 level might assist in the diagnosis of AIS in patients with T2DM. 展开更多
关键词 KI-67 Type 2 diabetes mellitus Lung adenocarcinoma in situ IMMUNOHISTOCHEMISTRY Prognostic marker
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智能手机成瘾对大学生创造力的作用机理研究
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作者 陈可 颜海睿 +2 位作者 邹严宇 殷华阳 黄岩清 《教育教学研究前沿》 2025年第6期193-195,共3页
以在校大学生为研究对象,基于情绪认知理论,构建智能手机成瘾对大学生创造力的影响效应及作用机理,探究情绪焦虑、自我效能感在以上关系中的中介效应。数据分析结果显示:智能手机成瘾负向影响大学生创造力;情绪焦虑和自我效能感手机成... 以在校大学生为研究对象,基于情绪认知理论,构建智能手机成瘾对大学生创造力的影响效应及作用机理,探究情绪焦虑、自我效能感在以上关系中的中介效应。数据分析结果显示:智能手机成瘾负向影响大学生创造力;情绪焦虑和自我效能感手机成瘾与创造力之间起部分中介作用;情绪焦虑和自我效能感在手机成瘾与创造力之间起链式中介效应。 展开更多
关键词 手机成瘾 创造力 情绪焦虑 创新自我效能感
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Strength and dilatancy of an unsaturated expansive soil at high suction levels
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作者 ke chen Xuzhen He +1 位作者 Fayun Liang Daichao Sheng 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第8期5079-5088,共10页
A series of suction-controlled triaxial tests was conducted on Nanyang expansive clay to investigate the effects of dry density and suction on dilatancy and strength.The suction of the soil samples was controlled usin... A series of suction-controlled triaxial tests was conducted on Nanyang expansive clay to investigate the effects of dry density and suction on dilatancy and strength.The suction of the soil samples was controlled using a vapour equilibrium technique,with four suction levels ranging from 3.29 MPa to 198.14 MPa,where water retention is dominated by adsorption.The experimental results show that the tested soil exhibits a brittle failure mode under high suction,significantly distinguishing the hydro-mechanical behaviour of the soil at high suction from that observed at low suction.This brittle failure mode significantly increases the contribution of suction to peak strength compared to residual strength,causes the soil to fail before reaching the critical state,a phenomenon not observed in soils under high suction,and results in dilatancy caused by damage to the soil particle aggregates rather than particle rearrangement.The dilatancy data obtained from the triaxial tests reveal that significant soil dilatancy occurs during shear after reaching peak strength,with the maximum dilatancy angle increasing with suction and decreasing with confining pressure.However,the initial dry density has a negligible impact on the soil's dilatancy under high suction levels.This observation further supports that,for unsaturated soils under high suction levels,dilatancy is attributed to damage to soil particle aggregates rather than the rearrangement of soil particles. 展开更多
关键词 DILATANCY Critical state Shear strength Unsaturated soil
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The Mechanism of Cornus officinalis Total Glycosides and Cornus Polysaccharide on Myocardial Protection in Rats with Acute Myocardial Infarction 被引量:3
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作者 ke chen Jianjun Li +3 位作者 kefang chen Xiangping Hou Huachao Mai Xiaojin Xue 《Chinese Medicine》 2016年第2期45-54,共10页
Objective: To investigate effects of Cornus officinalis Total Glycosides (COTG) and Cornus Polysaccharide (CP) on myocardial protection and on expression of mitochondria biogenesis related gene of acute myocardial inf... Objective: To investigate effects of Cornus officinalis Total Glycosides (COTG) and Cornus Polysaccharide (CP) on myocardial protection and on expression of mitochondria biogenesis related gene of acute myocardial infarction (AMI) rats, Materials and Methods: Ninety-six SD rats of SPF level were randomly divided into 5 groups: sham operation group, model group, preventive treatment group, COTG treatment group, CP treatment group, and there were 12 cases in each one. By legating the left anterior descending branch of coronary artery method, acute myocardial infarction model was established. The rat of sham operation group and model group was intragastric administered with physiological saline;other groups were given with corresponding drugs. The cardiac function, the myocardial infarct area, the expression of mitochondrial biogenesis genes such as PGC-1α, PGC-1β, NRF-1mRNA and GSK-3β mRNA, GSK-3β Protein Expression were analyzed. Results: The results revealed that compared with model group, myocardial infarction size, LVDs, LVDd, LVESV, LVEDP, and -dp/dt decreased;LVSP increased in preventive treatment group, COTG treatment group, and CP treatment group (p < 0.05);LVEDV increased in preventive treatment group (p < 0.05), PGC 1 alpha, and PGC 1 beta;the NRF-1 mRNA expression increased in preventive treatment group, COTG treatment group, and CP treatment group (p < 0.05). Compared with CP and COTG treatment group, PGClpha, beta PGC 1, the NRF-1 mRNA expression increased in preventive treatment group (p < 0.05). Compared with the sham operation group, GSK-3 beta mRNA and protein expression increased in model group, preventive treatment group, COTG treatment group, and CP treatment group (p < 0.05). Compared with model group, GSK-3 beta mRNA expression reduced in preventive treatment group, COTG treatment group, and CP treatment group (p Cornus officinalis total glycosides and Cornus polysaccharides can effectively protect myocardial mitochondria of acute myocardial infarction rats by activating GSK-3β signaling pathways, and reduce the myocardial infarct size, which has great significance for improving cardiac function. 展开更多
关键词 Cornus officinalis Total Glycosides Cornus Polysaccharide Acute Myocardial Infarction Glycogen Synthase Kinase 3 Beta
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钙离子浓度对脂肪干细胞增殖和成肌分化的影响 被引量:2
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作者 陈皓 柯晨 +2 位作者 张梓凯 李力群 林明 《现代生物医学进展》 CAS 2022年第7期1206-1210,共5页
目的:本研究旨在探讨钙离子浓度对脂肪干细胞(ADSCs)增殖和成肌分化的影响。方法:利用抽脂手术废弃脂肪提取脂肪干细胞,进行体外细胞培养和鉴定。设立正常细胞培养液为对照组,在培养液中添加不同浓度的钙离子(分别为0.001 mol/mL、0.002... 目的:本研究旨在探讨钙离子浓度对脂肪干细胞(ADSCs)增殖和成肌分化的影响。方法:利用抽脂手术废弃脂肪提取脂肪干细胞,进行体外细胞培养和鉴定。设立正常细胞培养液为对照组,在培养液中添加不同浓度的钙离子(分别为0.001 mol/mL、0.002 mol/mL、0.003 mol/mL、0.004 mol/mL、0.005 mol/mL共5组)为实验组,测定在48 h和96 h条件下不同浓度钙离子(Ca^(2+))对cck8反应细胞增殖的影响。同时通过TGF-β诱导成肌分化,测定不同钙离子浓度下Ca^(2+)信号相关蛋白的表达,并通过CCK-8检测评价其分化水平。另外通过免疫荧光和PCR检测细胞表面特异性抗原(α-SMA,SMMHC)的表达水平。各组间比较应用独立样本t检验,P<0.05为差异具有统计学意义。结果:显微镜下观察可见原代ADSCs细胞培养0.5天后贴壁生长,形态呈圆或椭圆形,而TGF-β诱导ADSCs成肌分化可见细胞呈梭形;实验组中,钙浓度<0.002 mmol/mL时,脂肪干细胞增殖得到显著促进(t=10.08,df=10,P<0.05);钙浓度<0.003 mmol/mL时,脂肪干细胞的成肌分化也显著增加,同时免疫荧光和PCR检测发现低浓度下α-SMA,SMMHC的表达均显著增加(P<0.05),而高钙浓度下两者均受到抑制(P<0.05)。结论:低钙浓度(钙浓度<0.002 mmol/mL)可显著促进脂肪干细胞增殖和成肌分化,而高钙浓度下两者均受到抑制。 展开更多
关键词 钙离子 脂肪干细胞 成肌分化 细胞增殖 表面特异性抗原
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含添加剂高压细水雾抑灭乙醇池火性能研究 被引量:3
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作者 彭伟 柯陈 +1 位作者 俞晨 邹浩 《消防科学与技术》 CAS 北大核心 2022年第8期1088-1093,共6页
为探究含NaCl、KCl、NaCO、KCO、NaHCO、KHCO六种碱金属盐以及SDBS、CAB35、APG0810三种起泡剂对高压细水雾抑灭乙醇池火性能的影响,在空间尺寸为6 m×6m×4 m的受限空间内开展纯高压细水雾与含不同添加剂的高压细水雾对乙醇池... 为探究含NaCl、KCl、NaCO、KCO、NaHCO、KHCO六种碱金属盐以及SDBS、CAB35、APG0810三种起泡剂对高压细水雾抑灭乙醇池火性能的影响,在空间尺寸为6 m×6m×4 m的受限空间内开展纯高压细水雾与含不同添加剂的高压细水雾对乙醇池火抑灭性能的对比实验。结果显示:相比纯高压细水雾灭火,添加碱金属盐与起泡剂的高压细水雾的灭火时间明显缩短,并且缩短的主要是处在火焰被撕裂抑制、火焰向周围游走阶段的时间;其他条件不变时,灭火时间随着添加剂浓度的增加先减小后增大,与纯高压细水雾相比,两类添加剂中各自灭火时间最短的分别为含3%KHCO、3%SDBS的高压细水雾,可分别缩短灭火时间57.4%、64.6%;平均降温速率随着添加剂浓度的增加先增大后减小,降温速率最高的为含3%SDBS的细水雾,相较于纯高压细水雾提高了217.54%;含不同碱金属盐与起泡剂的高压细水雾对乙醇池火的抑灭性能各不相同,但与纯高压细水雾相比都得到显著提高。 展开更多
关键词 高压细水雾 乙醇池火 碱金属盐 起泡剂 平均降温速率 抑灭性能
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基于试验函数的霍普夫分岔搜索新算法与电压稳定指标分析 被引量:1
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作者 王庆红 ke chen 《电工技术学报》 EI CSCD 北大核心 2008年第1期120-128,共9页
本文首先回顾了现有的一般分岔理论领域中搜索霍普夫分岔的主要方法及其局限性,而后试图将成熟的折叠分岔点的搜索办法和指标体系推广到霍普夫分岔的情形,文章基于矩阵张量积和交换积的概念,提出了霍普夫分岔试验函数及其对应的霍普夫... 本文首先回顾了现有的一般分岔理论领域中搜索霍普夫分岔的主要方法及其局限性,而后试图将成熟的折叠分岔点的搜索办法和指标体系推广到霍普夫分岔的情形,文章基于矩阵张量积和交换积的概念,提出了霍普夫分岔试验函数及其对应的霍普夫分岔指标和算法,文中提出的霍普夫试验函数不但具有普适性,而且基于指标的试验函数给出了当前运行点到霍普夫分岔点的距离,最后通过一个典型的动态测试系统分析,得出了很多有创新价值的结论。 展开更多
关键词 电力系统 霍普夫分岔 奇异性 电压稳定性指标 电压崩溃
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Analyzing the Form-Finding of a Large-Span Transversely Stiffened Suspended Cable System: A Method Considering Construction Processes
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作者 Junyu chen Yanfei Wang +2 位作者 ke chen Shiqing Huang Xiaowen Xu 《World Journal of Engineering and Technology》 2024年第2期229-244,共16页
The precise control of the shape of transversely stiffened suspended cable systems is crucial. However, existing form-finding methods primarily rely on iterative calculations that treat loads as fixed known conditions... The precise control of the shape of transversely stiffened suspended cable systems is crucial. However, existing form-finding methods primarily rely on iterative calculations that treat loads as fixed known conditions. These methods are inefficient and fail to accurately control shape results. In this study, we propose a form-finding method that analyzes the load response of models under different sag and stress levels, taking into account the construction process. To analyze the system, a structural finite element model was established in ANSYS, and geometric nonlinear analysis was conducted using the Newton-Raphson method. The form-finding analysis results demonstrate that the proposed method achieves precise control of shape, with a maximum shape error ranging from 0.33% to 0.98%. Furthermore, the relationships between loads and tension forces are influenced by the deformed shape of the structures, exhibiting significant geometric nonlinear characteristics. Meanwhile, the load response analysis reveals that the stress level of the self-equilibrium state in the transversely stiffened suspended cable system is primarily governed by strength criteria, while shape is predominantly controlled by stiffness criteria. Importantly, by simulating the initial tensioning process as an initial condition, this method solves for a counterweight that satisfies the requirements and achieves a self-equilibrium state with the desired shape. The shape of the self-equilibrium state is precisely controlled by simulating the construction process. Overall, this work presents a new method for analyzing the form-finding process of large-span transversely stiffened suspended cable system, considering the construction process which was often overlooked in previous studies. 展开更多
关键词 Cable Structure Long-Span Structure Form-Finding Analysis Finite Element Simulation Transverse Cable Stiffening System
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Effects of Cangfudaotan Tang on Expression of Organic Anion Transporting Polypeptide (oatp2b1) in Liver and Kidney Tissues of Rats with Phlegm Dampness Type Polycystic Ovary Syndrome (PCOS)
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作者 ke chen Aizhen Pan +2 位作者 Jianjun Li kefang chen Xiangping Hou 《Chinese Medicine》 2016年第4期166-174,共10页
Objective: To explore the effect of Cangfudaotan Tang on phlegm dampness type of PCOS and the role of oatp2b1 in transportation and transformation of phlegm dampness. Methods: 36 SD female rats were randomly divided i... Objective: To explore the effect of Cangfudaotan Tang on phlegm dampness type of PCOS and the role of oatp2b1 in transportation and transformation of phlegm dampness. Methods: 36 SD female rats were randomly divided into three groups: blank control group, model group and Cangfudaotan Tang group, 12 cases in each one. After PCOS rat models were made, rats of Cangfudaotan Tang group were treated with Cangfudaotan Tang (1.42 g/kg/d) by intragastric administration for 14 days;blank control and model group were given with isodose saline. The expression of oatp2b1 mRNA/Protein in liver and kidney tissues was measured and the level of testosterone (T), follicle stimulating hormone(FSH), estradiol (E<sub>2</sub>), luteinizing hormone(LH), Serum total cholesterol (TG), Triacylglycerols (TC), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) were detected at the same time. Results: Compared with blank control group, the expression of oatp2b1 mRNA and the level of TC, TG, LDL, LH, FSH, T in model group were significantly increased (P < 0. 05), while the level of HDL was significantly decreased (P < 0. 05);compared with model group, the expression of oatp2b1 mRNA and the level of TC, TG, LDL in Cangfudaotan Tang group were significantly lowered (P < 0.05);the level of HDL was significantly higher;the oatp2b1 protein in kidney and liver tissues had different degrees of expression, while there was no statistical significance among the three groups. Conclusions: Oatp2b1 might be one of the material bases participating in transportation and transformation of phlegmy dampness. The mechanism of Cangfudaotan Tang treating phlegm dampness type of PCOS may be achieved by regulating the expression of oatp2b1. 展开更多
关键词 Cangfudaotan Tang Polycystic Ovary Syndrome Phlegm Dampness Organic Anion Transporting Polypeptide Oatp2b1
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