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Voluntary wheel running ameliorated the deleterious effects of high-fat diet on glucose metabolism,gut microbiota and microbial-associated metabolites
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作者 Ling Zhang Wenyu Zou +4 位作者 Yongyan Hu Honghua Wu Ying Gao Junqing Zhang Jia Zheng 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1672-1684,共13页
Exercise training is critical for the early prevention and treatment of obesity and diabetes mellitus.However,the mechanism with gut microbiota and fecal metabolites underlying the effects of voluntary wheel running o... Exercise training is critical for the early prevention and treatment of obesity and diabetes mellitus.However,the mechanism with gut microbiota and fecal metabolites underlying the effects of voluntary wheel running on high-fat diet induced abnormal glucose metabolism has not been fully elaborated.C57BL/6 male mice were randomly assigned to 4 groups according to diets(fed with normal chow diet or high-fat diet)and running paradigm(housed in static cage or with voluntary running wheel).An integrative 16S rDNA sequencing and metabolites profiling was synchronously performed to characterize the effects of voluntary wheel running on gut microbiota and metabolites.It showed that voluntary wheel running prevented the detrimental effects of high-fat feeding on glucose metabolism 16S rDNA sequencing showed remarkable changes in Rikenella and Marvinbryantia genera.Metabolic profiling indicated multiple altered metabolites,which were enriched in secondary bile acid biosynthesis signaling.In conclusion,our study indicated that voluntary wheel running significantly improved glucose metabolism and counteracted the deleterious effects of high-fat feeding on body weight and glucose intolerance.We further found that voluntary wheel running could integratively program gut microbiota composition and fecal metabolites changes,and may regulate muricholic acid metabolism and secondary bile acid biosynthesis in high-fat fed mice. 展开更多
关键词 High-fat diet Voluntary wheel running Gut microbiota Metabolomics Glucose metabolism
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Influence of pier height on the safety of trains running on high-speed railway bridges during earthquakes
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作者 NIE Yu-tao GUO Wei +8 位作者 JIANG Li-zhong YU Zhi-wu ZENG Chen WANG Yang HE Xu-en REN Shao-xun HUANG Ren-qiang LIANG Guang-yue LI Chang-qing 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2102-2115,共14页
Sudden earthquakes pose a threat to the running safety of trains on high-speed railway bridges,and the stiffness of piers is one of the factors affecting the dynamic response of train-track-bridge system.In this paper... Sudden earthquakes pose a threat to the running safety of trains on high-speed railway bridges,and the stiffness of piers is one of the factors affecting the dynamic response of train-track-bridge system.In this paper,a experiment of a train running on a high-speed railway bridge is performed based on a dynamic experiment system,and the corresponding numerical model is established.The reliability of the numerical model is verified by experiments.Then,the experiment and numerical data are analyzed to reveal the pier height effects on the running safety of trains on bridges.The results show that when the pier height changes,the frequency of the bridge below the 30 m pier height changes greater;the increase of pier height causes the transverse fundamental frequency of the bridge close to that of the train,and the shaking angle and lateral displacement of the train are the largest for bridge with 50 m pier,which increases the risk of derailment;with the pier height increases from 8 m to 50 m,the derailment coefficient obtained by numerical simulations increases by 75% on average,and the spectral intensity obtained by experiments increases by 120% on average,two indicators exhibit logarithmic variation. 展开更多
关键词 pier height high-speed railway bridge running safety numerical model
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Enhancement of motor functional recovery in thoracic spinal cord injury: voluntary wheel running versus forced treadmill exercise
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作者 Do-Hun Lee Dan Cao +4 位作者 Younghye Moon Chen Chen Nai-Kui Liu Xiao-Ming Xu Wei Wu 《Neural Regeneration Research》 SCIE CAS 2025年第3期836-844,共9页
Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery ... Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery and morphological changes following thoracic contusive spinal cord injury. After a 7-day recovery period after spinal cord injury, mice were assigned to either a trained group(10 weeks of voluntary running wheel or forced treadmill exercise) or an untrained group. Bi-weekly assessments revealed that the exercise-trained group, particularly the voluntary wheel exercise subgroup, displayed significantly improved locomotor recovery, more plasticity of dopaminergic and serotonin modulation compared with the untrained group. Additionally, exercise interventions led to gait pattern restoration and enhanced transcranial magnetic motor-evoked potentials. Despite consistent injury areas across groups, exercise training promoted terminal innervation of descending axons. In summary, voluntary wheel exercise shows promise for enhancing outcomes after thoracic contusive spinal cord injury, emphasizing the role of exercise modality in promoting recovery and morphological changes in spinal cord injuries. Our findings will influence future strategies for rehabilitation exercises, restoring functional movement after spinal cord injury. 展开更多
关键词 behavioral assessment motor function neural plasticity running wheel exercise spinal cord injury treadmill exercise voluntary exercise
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Acute effect of foot strike patterns on in vivo tibiotalar and subtalar joint kinematics during barefoot running
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作者 Dongqiang Ye Lu Li +4 位作者 Shen Zhang Songlin Xiao Xiaole Sun Shaobai Wang Weijie Fu 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期108-117,共10页
Background:Foot kinematics,such as excessive eversion and malalignment of the hindfoot,are believed to be associated with running-related injuries.The maj ority of studies to date show that different foot strike patte... Background:Foot kinematics,such as excessive eversion and malalignment of the hindfoot,are believed to be associated with running-related injuries.The maj ority of studies to date show that different foot strike patterns influence these specific foot and ankle kinematics.However,technical deficiencies in traditional motion capture approaches limit knowledge of in vivo joint kinematics with respect to rearfoot and forefoot strike patterns(RFS and FFS,respectively).This study uses a high-speed dual fluoroscopic imaging system(DFIS)to determine the effects of different foot strike patterns on 3D in vivo tibiotalar and subtalar joints kinematics.Methods:Fifteen healthy male recreational runners underwent foot computed tomography scanning for the construction of 3-dimensional models.A high-speed DFIS(100 Hz)was used to collect 6 degrees of freedom kinematics for participants’tibiotalar and subtalar joints when they adopted RFS and FFS in barefoot condition.Results:Compared with RFS,FFS exhibited greater internal rotation at 0%-20%of the stance phase in the tibiotalar joint.The peak internal rotation angle of the tibiotalar joint under FFS was greater than under RFS(p<0.001,Cohen’s d=0.92).RFS showed more dorsiflexion at 0%-20%of the stance phase in the tibiotalar joint than FFS.RFS also presented a larger anterior translation(p<0.001,Cohen’s d=1.28)in the subtalar joint at i nitial contact than FFS.Conclusion:Running with acute barefoot FFS increases the internal rotation of the tibiotalar joint in the early stance.The use of high-speed DFIS to quantify the movement of the tibiotalar and subtalar joint was critical to revealing the effects of RF S and FFS during running. 展开更多
关键词 Foot strike patterns High-speed dual fluoroscopic imaging system In vivo kinematics running
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Running safety assessment method of trains under seismic conditions based on the derailment risk domain
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作者 Zhihui Zhu Gaoyang Zhou +2 位作者 Weiqi Zheng Wei Gong Yongjiu Tang 《Railway Engineering Science》 EI 2024年第4期499-517,共19页
The accurate assessment of running safety during earthquakes is of significant importance for ensuring the safety of railway lines.Currently,assessment methods based on a single index suffer from issues such as misjud... The accurate assessment of running safety during earthquakes is of significant importance for ensuring the safety of railway lines.Currently,assessment methods based on a single index suffer from issues such as misjudgment of operational safety and difficulty in evaluating operational margin,making them unsuitable for assessing train safety during earthquakes.Therefore,in order to propose an effective evaluation method for the running safety of trains during earthquakes,this study employs three indexes,namely lateral displacement of the wheel–rail contact point,wheel unloading rate,and wheel lift,to describe the lateral and vertical contact states between the wheel and rail.The corresponding evolution characteristics of the wheel–rail contact states are determined,and the derailment forms under different frequency components of seismic motion are identified through dynamic numerical simulations of the train–track coupled system under sine excitation.The variations in the wheel–rail contact states during the transition from a safe state to the critical state of derailment are analyzed,thereby constructing the evolutionary path of train derailment and seismic derailment risk domain.Lastly,the wheel–rail contact and derailment states under seismic conditions are analyzed,thus verifying the effectiveness of the evaluation method for assessing running safety under earthquakes proposed in this study.The results indicate that the assessment method based on the derailment risk domain accurately and comprehensively reflects the wheel–rail contact states under seismic conditions.It successfully determines the forms of train derailment,the risk levels of derailment,and the evolutionary paths of derailment risk. 展开更多
关键词 Earthquake High-speed train running safety Wheel–rail contact Derailment risk domain
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A novel refined dynamic model of high-speed maglev train-bridge coupled system for random vibration and running safety assessment
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作者 MAO Jian-feng LI Dao-hang +3 位作者 YU Zhi-wu CAI Wen-feng GUO Wei ZHANG Guang-wen 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2532-2544,共13页
Running safety assessment and tracking irregularity parametric sensitivity analysis of high-speed maglev train-bridge system are of great concern,especially need perfect refinement models in which all properties can b... Running safety assessment and tracking irregularity parametric sensitivity analysis of high-speed maglev train-bridge system are of great concern,especially need perfect refinement models in which all properties can be well characterized based on various stochastic excitations.A three-dimensional refined spatial random vibration analysis model of high-speed maglev train-bridge coupled system is established in this paper,in which multi-source uncertainty excitation can be considered simultaneously,and the probability density evolution method(PDEM)is adopted to reveal the system-specific uncertainty dynamic characteristic.The motion equation of the maglev vehicle model is composed of multi-rigid bodies with a total 210-degrees of freedom for each vehicle,and a refined electromagnetic force-air gap model is used to account for the interaction and coupling effect between the moving train and track beam bridges,which are directly established by using finite element method.The model is proven to be applicable by comparing with Monte Carlo simulation.By applying the proposed stochastic framework to the high maglev line,the random dynamic responses of maglev vehicles running on the bridges are studied for running safety and stability assessment.Moreover,the effects of track irregularity wavelength range under different amplitude and running speeds on the coupled system are investigated.The results show that the augmentation of train speed will move backward the sensitive wavelength interval,and track irregularity amplitude influences the response remarkably in the sensitive interval. 展开更多
关键词 maglev train-bridge interaction electromagnetic force-air gap model stochastic dynamic analysis running safety assessment probability density evolution method
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Modified DS np Chart Using Generalized Multiple Dependent State Sampling under Time Truncated Life Test
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作者 Wimonmas Bamrungsetthapong Pramote Charongrattanasakul 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2471-2495,共25页
This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of t... This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of the product based on the time truncated life test employing theWeibull distribution.The control chart developed supports the examination of the mean lifespan variation for a particular product in the process of manufacturing.Three control limit levels are used:the warning control limit,inner control limit,and outer control limit.Together,they enhance the capability for variation detection.A genetic algorithm can be used for optimization during the in-control process,whereby the optimal parameters can be established for the proposed control chart.The control chart performance is assessed using the average run length,while the influence of the model parameters upon the control chart solution is assessed via sensitivity analysis based on an orthogonal experimental design withmultiple linear regression.A comparative study was conducted based on the out-of-control average run length,in which the developed control chart offered greater sensitivity in the detection of process shifts while making use of smaller samples on average than is the case for existing control charts.Finally,to exhibit the utility of the developed control chart,this paper presents its application using simulated data with parameters drawn from the real set of data. 展开更多
关键词 Modified DS np chart generalizedmultiple dependent state sampling time truncated life test Weibull distribution average run length average sample size
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SmartMicro Grid Energy System Management Based on Optimum Running Cost for Rural Communities in Rwanda
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作者 Fabien Mukundufite Jean Marie Vianney Bikorimana Alexander Kyaruzi Lugatona 《Energy Engineering》 EI 2024年第7期1805-1821,共17页
The governmental electric utility and the private sector are joining hands to meet the target of electrifying all households by 2024.However,the aforementioned goal is challenged by households that are scattered in re... The governmental electric utility and the private sector are joining hands to meet the target of electrifying all households by 2024.However,the aforementioned goal is challenged by households that are scattered in remote areas.So far,Solar Home Systems(SHS)have mostly been applied to increase electricity access in rural areas.SHSs have continuous constraints to meet electricity demands and cannot run income-generating activities.The current research presents the feasibility study of electrifying Remera village with the smart microgrid as a case study.The renewable energy resources available in Remera are the key sources of electricity in that village.The generation capacity is estimated based on the load profile.The microgrid configurations are simulated with HOMER,and the genetic algorithm is used to analyze the optimum cost.By analyzing the impact of operation and maintenance costs,the results show that the absence of subsidies increases the levelized cost of electricity(COE)five times greater than the electricity price from the public utility.The microgrid made up of PV,diesel generator,and batteries proved to be the most viable solution and ensured continuous power supply to customers.By considering the subsidies,COE reaches 0.186$/kWh,a competitive price with electricity from public utilities in Rwanda. 展开更多
关键词 Load demand load profile optimum running cost power demand satisfaction smart meters and smart micro grid
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Safety of the express freight train running over a long-span bridge
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作者 Jingcheng Wen Yihao Qin +1 位作者 Ye Bai Xiaoqing Dong 《Railway Sciences》 2024年第4期469-479,共11页
Purpose-Express freight transportation is in rapid development currently.Owing to the higher speed of express freight train,the deformation of the bridge deck worsens the railway line condition under the action of win... Purpose-Express freight transportation is in rapid development currently.Owing to the higher speed of express freight train,the deformation of the bridge deck worsens the railway line condition under the action of wind and train moving load when the train runs over a long-span bridge.Besides,the blunt car body of vehicle has poor aerodynamic characteristics,bringing a greater challenge on the running stability in the crosswind.Design/methodology/approach-In this study,the aerodynamic force coefficients of express freight vehicles on the bridge are measured by scale model wind tunnel test.The dynamic model of the train-long-span steel truss bridge coupling system is established,and the dynamic response as well as the running safety of vehicle are evaluated.Findings-The results show that wind speed has a significant influence on running safety,which is mainly reflected in the over-limitation of wheel unloading rate.The wind speed limit decreases with train speed,and it reduces to 18.83 m/s when the train speed is 160 km/h.Originality/value-This study deepens the theoretical understanding of the interaction between vehicles and bridges and proposes new methods for analyzing similar engineering problems.It also provides a new theoretical basis for the safety assessment of express freight trains. 展开更多
关键词 Express freight train Long-span bridge CROSSWIND Wind tunnel test running safety Paper type Research paper
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RUN和FYVE结构域蛋白1在胰腺癌中的表达特征及功能作用
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作者 钱志鑫 李俊强 +1 位作者 宋扬 苏海川 《空军军医大学学报》 CAS 2024年第7期769-774,共6页
目的探究RUN和FYVE结构域蛋白1(RUFY1)在胰腺癌中的表达特征及功能作用。方法通过分析癌症基因组图谱、临床蛋白质组肿瘤分析协作组、基因表达综合数据库等,探究RUFY1在胰腺癌中mRNA、蛋白的表达水平以及与胰腺癌患者预后关系。采用免... 目的探究RUN和FYVE结构域蛋白1(RUFY1)在胰腺癌中的表达特征及功能作用。方法通过分析癌症基因组图谱、临床蛋白质组肿瘤分析协作组、基因表达综合数据库等,探究RUFY1在胰腺癌中mRNA、蛋白的表达水平以及与胰腺癌患者预后关系。采用免疫组织化学染色比对胰腺癌患者肿瘤组织与正常胰腺组织中RUFY1蛋白表达水平。在胰腺癌细胞系中敲低RUFY1,并通过肿瘤成球、CCK-8、克隆形成实验验证RUFY1在胰腺癌细胞系中发挥的功能与作用。联合CTRP和PRISM等数据库探究RUFY1与部分抗肿瘤药物敏感性的关系。结果通过分析公共数据库发现,与正常胰腺组织相比,胰腺癌肿瘤组织中RUFY1 mRNA和蛋白表达水平显著升高(P<0.05,P<0.01);RUFY1的高表达与胰腺癌患者的预后呈显著负相关(P<0.05)。免疫组织化学染色结果表明,相较于癌旁组织,RUFY1蛋白表达水平在胰腺癌肿瘤组织中升高。肿瘤成球、CCK-8、克隆形成实验结果显示RUFY1敲低会显著抑制胰腺癌细胞系的增殖功能(P<0.01)。由CTRP和PRISM数据库分析得出,低RUFY1表达的患者对PD318088(P<0.01)、RITA(P<0.01)、selumetinib(P<0.05)、AZD8931(P<0.01)等药物更加敏感。结论RUFY1 mRNA及蛋白水平在胰腺癌肿瘤组织中升高,RUFY1的高表达与胰腺癌患者的预后呈负相关,敲低RUFY1可抑制胰腺癌细胞系的增殖能力,RUFY1有望成为用来预测临床用药治疗敏感性的靶点。 展开更多
关键词 run和FYVE结构域蛋白1 胰腺癌 药物敏感性 增殖能力
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Review of Research on English Translation of Chinese Running Sentences
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作者 ZHANG Wen-hui 《Journal of Literature and Art Studies》 2024年第7期624-627,共4页
In order to convey complete meanings,there is a phenomenon in Chinese of using multiple running sentences.Xu Jingning(2023,p.66)states,“In communication,a complete expression of meaning often requires more than one c... In order to convey complete meanings,there is a phenomenon in Chinese of using multiple running sentences.Xu Jingning(2023,p.66)states,“In communication,a complete expression of meaning often requires more than one clause,which is common in human languages.”Domestic research on running sentences includes discussions on defining the concept and structural features of running sentences,sentence properties,sentence pattern classifications and their criteria,as well as issues related to translating running sentences into English.This article primarily focuses on scholarly research into the English translation of running sentences in China,highlighting recent achievements and identifying existing issues in the study of running sentence translation.However,by reviewing literature on the translation of running sentences,it is found that current research in the academic community on non-core running sentences is limited.Therefore,this paper proposes relevant strategies to address this issue. 展开更多
关键词 Chinese running sentences TOPICS English-Chinese translation
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The modification and optimizing of the CHEMTAX running in the South China Sea 被引量:8
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作者 WANG Lei HUANG Bangqin +1 位作者 LIU Xin XIAO Wupeng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第2期124-131,共8页
In order to determine the phytoplankton community composition, the modification and optimizing of the CHEMical TAXonomy(CHEMTAX) running was carried out through samples grouping, successive run and evaluate the resu... In order to determine the phytoplankton community composition, the modification and optimizing of the CHEMical TAXonomy(CHEMTAX) running was carried out through samples grouping, successive run and evaluate the results for HPLC-pigment samples in the South China Sea(SCS). The vertical distribution of the ratio of pigment to total Chl a(TChl a) exhibited three different patterns, including increasing with depth pattern(e.g., But-Fuco), decreasing with depth pattern(e.g., Zea) and increasing at deep chlorophyll maximum(DCM) pattern(e.g., Hex-Fuco). The vertical profiles for Fuco/TChl a and Pras/TChl a was higher in coast than in the shelf and basin, and the Zea and Dv-Chl a expressed conversely. So the samples in the coastal stations must be separated for the cluster analysis group procedure in the SCS. Successive run was introduced into the CHEMTAX calculation and the output results were evaluated by the convergence of pigment/TChl a ratios. Most of the ratios were well converged at the fifth running, except Zea/TChl a for Prochlorococcus and Chl b/TChl a for prasinophytes and so on. To evaluate the fifth running's results, haptophytes_8 and chlorophytes were two phytoplankton groups with much uncertainty. But the fifth estimated value was better than running once was supported by the regression evidence between the measured pigment concentration and calculation values. Synechococcus was another component with much mutability, and the CHEMTAX's result should be compared to the flow cytometry's cell abundance. 展开更多
关键词 PHYTOPLANKTON CHEMTAX pigment/Chl a ratio successive run South China Sea
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A prediction model for horizontal run-out distance of landslides triggered by Wenchuan earthquake 被引量:6
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作者 Yang Changwei Zhang Jianjing Zhang Ming 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2013年第2期201-208,共8页
The peak ground acceleration (PGA), the volume of a sliding mass V, the height of a mountain HL and the slope angle θ of a mountain are four important parameters affecting the horizontal run-out distance of a lands... The peak ground acceleration (PGA), the volume of a sliding mass V, the height of a mountain HL and the slope angle θ of a mountain are four important parameters affecting the horizontal run-out distance of a landslide L. Correlations among them are studied statistically based on field investigations from 67 landslides triggered by the ground shaking and other factors during the Wenchuan earthquake, and then a prediction model for horizontal run-out distance L is developed in this study. This model gives due consideration to the implications of the above four parameters on the horizontal run-out distance L and the validity of the model is verified by the Donghekou and Magong Woqian landslides. At the same time, the advantages of the model are shown by comparing it with two other common prediction methods. The major findings drawn from the analyses and comparisons are: (1) an exponential relationship exists between L and log V, L and log HL, L and log PGA separately, but a negative exponential relationship exists between L and log tan0, which agrees with the statistical results; and (2) according to the analysis results of the relative relationship between the height of a mountain (H) and the place where the landslides occur, the probabilities at distances of2H/3-H, H/3-2H/3, and O-H/3 are 70.8%, 15.4%, and 13.8%, respectively, revealing that most landslides occurred at a distance of H/2-H. This prediction model can provide an effective technical support for the prevention and mitigation of landslide hazards. 展开更多
关键词 Wenchuan earthquake LANDSLIDES run-out distance prediction model relationship
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Systematic reduction of leg muscle activity throughout a standard assessment of running footwear
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作者 Maurice Mohr Vinzenzvon Tscharner +1 位作者 Sandro Nigg Benno M.Nigg 《Journal of Sport and Health Science》 SCIE 2022年第3期309-318,共10页
Purpose This study aimed to investigate whether there is a systematic change of leg muscle activity,as quantified by surface electromyography(EMG),throughout a standard running footwear assessment protocol at a predet... Purpose This study aimed to investigate whether there is a systematic change of leg muscle activity,as quantified by surface electromyography(EMG),throughout a standard running footwear assessment protocol at a predetermined running speed.Methods Thirty-one physically active adults(15 females and 16 males)completed 5 testing rounds consisting of overground running trials at a speed of 3.5 m/s.The level of muscle activity from 6 major leg muscles was recorded using surface EMG.The variables assessed were the EMG total intensity as a function of time and the cumulative EMG overall intensity.Systematic effects of the chronological testing round(independent variable)on the normalized EMG overall intensity(dependent variable)were examined using Friedman analysis of variates and post hoc pairwise Wilcoxon signed-rank tests(α=0.05).Results There was a systematic reduction in overall EMG intensity for all 6 muscles over the time course of the running protocol(p<0.001)until the fourth testing round when EMG intensities reached a steady state.The one exception was the biceps femoris muscle,which showed a significant reduction of EMG intensity during the stance phase(p<0.001)but not the swing phase(p=0.16).Conclusion While running at a predetermined speed,the neuromuscular system undergoes an adaptation process characterized by a progressive reduction in the activity level of major leg muscles.This process may represent an optimization strategy of the neuromuscular system towards a more energetically efficient running style.Future running protocols should include a familiarization period of at least 7 min or 600 strides of running at the predetermined speed. 展开更多
关键词 Muscle co-contraction running familiarization running footwear running shoes Surface electromyography
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Changes in ankle work,foot work,and tibialis anterior activation throughout a long run
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作者 Eric C.Honert Florian Ostermair +1 位作者 Vinzenzvon Tscharner Benno M.Nigg 《Journal of Sport and Health Science》 SCIE 2022年第3期330-338,共9页
Background The ankle and foot together contribute to over half of the positive and negative work performed by the lower limbs during running.Yet,little is known about how foot kinetics change throughout a run.The amou... Background The ankle and foot together contribute to over half of the positive and negative work performed by the lower limbs during running.Yet,little is known about how foot kinetics change throughout a run.The amount of negative foot work may decrease as tibialis anterior(TA)electromyography(EMG)changes throughout longer-duration runs.Therefore,we examined ankle and foot work as well as TA EMG changes throughout a changing-speed run.Methods Fourteen heel-striking subjects ran on a treadmill for 58 min.We collected ground reaction forces,motion capture,and EMG.Subjects ran at 110%,100%,and 90%of their 10-km running speed and 2.8 m/s multiple times throughout the run.Foot work was evaluated using the distal rearfoot work,which provides a net estimate of all work contributors within the foot.Results Positive foot work increased and positive ankle work decreased throughout the run at all speeds.At the 110%10-km running speed,negative foot work decreased and TA EMG frequency shifted lower throughout the run.The increase in positive foot work may be attributed to increased foot joint work performed by intrinsic foot muscles.Changes in negative foot work and TA EMG frequency may indicate that the TA plays a role in negative foot work in the early stance of a run.Conclusion This study is the first to examine how the kinetic contributions of the foot change throughout a run.Future studies should investigate how increases in foot work affect running performance. 展开更多
关键词 ELECTROMYOGRAPHY FOOTWEAR running performance
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Neuromuscular,biomechanical,and energetic adjustments following repeated bouts of downhill running
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作者 Arash Khassetarash Gianluca Vernillo +2 位作者 Renata L.Krüger W.Brent Edwards Guillaume Y.Millet 《Journal of Sport and Health Science》 SCIE 2022年第3期319-329,共11页
Purpose This study used downhill running as a model to investigate the repeated bout effect(RBE)on neuromuscular performance,running biomechanics,and metabolic cost of running.Methods Ten healthy recreational male run... Purpose This study used downhill running as a model to investigate the repeated bout effect(RBE)on neuromuscular performance,running biomechanics,and metabolic cost of running.Methods Ten healthy recreational male runners performed two 30-min bouts of downhill running(DR1 and DR2)at a-20%slope and 2.8 m/s 3 weeks apart.Neuromuscular fatigue,level running biomechanics during slow and fast running,and running economy parameters were recorded immediately before and after the downhill bouts,and at 24 h,48 h,72 h,96 h,and 168 h thereafter(i.e.,follow-up days).Results An RBE was confirmed by attenuated muscle soreness and serum creatine kinase rise after DR2 compared to DR1.An RBE was also observed in maximum voluntary contraction(MVC)force loss and voluntary activation where DR2 resulted in attenuated MVC force loss and voluntary activation immediately after the run and during follow-up days.The downhill running protocol significantly influenced level running biomechanics;an RBE was observed in which center of mass excursion and,therefore,lower-extremity compliance were greater during follow-up days after DR1 compared to DR2.The observed changes in level running biomechanics did not influence the energy cost of running.Conclusion This study demonstrated evidence of adaptation in neural drive as well as biomechanical changes with the RBE after DR.The higher neural drive resulted in attenuated MVC force loss after the second bout.It can be concluded that the RBE after downhill running manifests as changes to global and central fatigue parameters and running biomechanics without substantially altering the energy cost of running. 展开更多
关键词 Cost of running Eccentric exercise Fatigue Muscle damage
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Free running period affected by network structures of suprachiasmatic nucleus neurons exposed to constant light
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作者 周建 顾长贵 +1 位作者 宋雨轩 许艳 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期566-572,共7页
Exposed to the natural light-dark cycle,24 h rhythms exist in behavioral and physiological processes of living beings.Interestingly,under constant darkness or constant light,living beings can maintain a robust endogen... Exposed to the natural light-dark cycle,24 h rhythms exist in behavioral and physiological processes of living beings.Interestingly,under constant darkness or constant light,living beings can maintain a robust endogenous rhythm with a free running period(FRP)close to 24 h.In mammals,the circadian rhythm is coordinated by a master clock located in the suprachiasmatic nucleus(SCN)of the brain,which is composed of about twenty thousand self-oscillating neurons.These SCN neurons form a heterogenous network to output a robust rhythm.Thus far,the exact network topology of the SCN neurons is unknown.In this article,we examine the effect of the SCN network structure on the FRP when exposed to constant light by a Poincare model.Four typical network structures are considered,including a nearest-neighbor coupled network,a Newman-Watts small world network,an Erd¨os-Renyi random network and a Barabasi-Albert(BA)scale free network.The results show that the FRP is longest in the BA network,because the BA network is characterized by the most heterogeneous structure among these four types of networks.These findings are not affected by the average node degree of the SCN network or the value of relaxation rate of the SCN neuronal oscillators.Our findings contribute to the understanding of how the network structure of the SCN neurons influences the FRP. 展开更多
关键词 circadian rhythm light sensitivity heterogeneous network free running period
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Does orthotics use improve comfort,speed,and injury rate during running?A randomised control trial
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作者 Alice E Fortune Jonathan M G Sims George Ampat 《World Journal of Orthopedics》 2023年第5期348-361,共14页
BACKGROUND Running is a hugely popular sport.Unfortunately,running-related injury(RRI)rates are high,particularly amongst amateur and recreational runners.Finding ways to reduce RRI rates and maximise comfort and perf... BACKGROUND Running is a hugely popular sport.Unfortunately,running-related injury(RRI)rates are high,particularly amongst amateur and recreational runners.Finding ways to reduce RRI rates and maximise comfort and performance for runners is important.Evidence regarding whether orthotics can successfully improve these parameters is limited and contradicting.Further research is required to provide runners with clearer guidance on the usefulness of orthotics.AIM To investigate the effect of Aetrex Orthotics on comfort,speed and RRI rates during recreational running.METHODS One hundred and six recreational runners were recruited on a voluntary basis via running clubs and social media pages and randomised into either the intervention or control group.Participants in the intervention group ran with Aetrex L700 Speed Orthotics inserted in their usual running shoes,whilst participants in the control group ran in their usual running shoes with no orthotics.The study ran for an 8-wk period.Participants provided data relating to running comfort,distance,and time during weeks 3-6.Participants provided data relating to any RRIs they sustained during all 8 wks.Running distance and time were used to calculate running speed in miles per hour(mph).For each outcome variable,95%confidence intervals and P values were calculated to assess the statistical significance between the groups.For comfort and speed data,univariate multi-level analysis was performed,and for outcome variables with significant between group differences,multi-level multivariate analysis was performed to evaluate any confounding effects of gender and age.RESULTS Ninety-four participants were included in the final analysis(drop-out rate=11%).Comfort and speed from 940 runs and 978 injury data reports were analysed.Participants who ran with orthotics reported,on average,speeds 0.30 mph faster(P=0.20)and comfort scores 1.27 points higher(P≤0.001)than participants who ran with no orthotics.They were also 2.22 times less likely to sustain an injury(P=0.08)than participants who ran with no orthotics.However,findings were only significant for comfort and not for speed or injury rates.Age and gender were found to be significant predictors of comfort.However,the improvements in comfort reported by participants who ran with orthotics were still significant after adjusting for age and gender.CONCLUSION This study found orthotics to improve comfort and speed and prevent RRIs whilst running.However,these findings were only statistically significant for comfort. 展开更多
关键词 running Foot orthoses running related injuries PAIN Patient comfort Athletic performance
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Pile Running in Layered Soils
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作者 ZHAO Huan WANG Le +3 位作者 SUN Li-qiang TIAN Ying-hui Oliver REUL CHEN Quan-zhen 《China Ocean Engineering》 SCIE EI CSCD 2023年第5期829-841,共13页
This paper presents a case study on incidents of offshore pile running in layered soils.The study provides a detailed description of the seabed soil data,pile driving records,and field surveillance video observations.... This paper presents a case study on incidents of offshore pile running in layered soils.The study provides a detailed description of the seabed soil data,pile driving records,and field surveillance video observations.Three-dimensional large deformation finite element(LDFE)analyses were conducted to retrospectively analyze the incidents,considering the remoulding of seabed soil and degradation of the pile-soil interface in the LDFE modeling.By comparing the field observations with the LDFE analysis,the mechanism of pile running was discussed,with a focus on investigating the pile penetration resistance in each layer.The study revealed that pile running in layered soils primarily resulted from a significant reduction in pile base resistance when transitioning from a strong layer to an adjacent weak layer.To further investigate the pile running mechanism in layered soils,a parametric study on the strength variation of adjacent soil layers and its influence on pile base resistance was conducted.Lastly,a simplified prediction model of pile base resistance,suitable for assessing the risk of pile running in layered soils,was proposed. 展开更多
关键词 pile running coupled Eulerian−Lagrangian method layered soil penetration resistance pile−soil interaction
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Rural Doctor Runs‘Daddy Daycare’in Southwest China
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《The Journal of Human Rights》 2012年第2期9-10,共2页
In the past four years, Lan Chengshan has provided a "parents love" to more than 200 children. The 34-year-old doctor oper- ates a medical clinic in Lianhua, a remote village in Southwest China's Guizhou province.... In the past four years, Lan Chengshan has provided a "parents love" to more than 200 children. The 34-year-old doctor oper- ates a medical clinic in Lianhua, a remote village in Southwest China's Guizhou province. He's also the headmaster of a kindergarten, just like Eddie Murphy's role in the Hollywood film, Daddy Davcare. 展开更多
关键词 in Southwest China Daddy Daycare Rural Doctor runs THAN
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