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Modal analysis on a fluid-conveying pipe subject to elastic supports with unknown-but-bounded parameters
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作者 Sha Wei Xulong Li +2 位作者 Xiong Yan Hu Ding Liqun Chen 《Acta Mechanica Sinica》 2026年第1期310-324,共15页
Uncertain parameters are widespread in engineering systems.This study investigates the modal analysis of a fluid-conveying pipe subjected to elastic supports with unknown-but-bound parameters.The governing equation fo... Uncertain parameters are widespread in engineering systems.This study investigates the modal analysis of a fluid-conveying pipe subjected to elastic supports with unknown-but-bound parameters.The governing equation for the elastically supported fluid-conveying pipe is transformed into ordinary differential equations using the Galerkin truncation method.The Chebyshev interval approach,integrated with the assumed mode method is then used to investigate the effects of uncertainties of support stiffness,fluid speed,and pipe length on the natural frequencies and mode shapes of the pipe.Additionally,both symmetrical and asymmetrical support stiffnesses are discussed.The accuracy and effectiveness of the Chebyshev interval approach are verified through comparison with the Monte Carlo method.The results reveal that,for the same deviation coefficient,uncertainties in symmetrical support stiffness have a greater impact on the first four natural frequencies than those of the asymmetrical one.There may be significant differences in the sensitivity of natural frequencies and mode shapes of the same order to uncertain parameters.Notably,mode shapes susceptible to uncertain parameters exhibit wider fluctuation intervals near the elastic supports,requiring more attention. 展开更多
关键词 Fluid-conveying pipe Elastic support UNCERTAINTY Modal analysis Chebyshev interval method
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Observation of the clinical efficacy of sitting-position knee adjustment Tuina manipulation and ultrasonic treatment for knee osteoarthritis and the impact on gait analysis parameters
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作者 KANG Zhiran GONG Li +5 位作者 XING Hua FU Yangyang XU Wenshuai MENG Fanchao SU Xiaojie SUN Wuquan 《Journal of Acupuncture and Tuina Science》 2026年第1期69-80,共12页
Objective:To observe the clinical efficacy of sitting-position knee adjustment Tuina(Chinese therapeutic massage)and therapeutic ultrasound in treating knee osteoarthritis(KOA)and the impact on gait analysis parameter... Objective:To observe the clinical efficacy of sitting-position knee adjustment Tuina(Chinese therapeutic massage)and therapeutic ultrasound in treating knee osteoarthritis(KOA)and the impact on gait analysis parameters.Methods:In a randomized controlled design,80 KOA patients were randomly allocated to a manipulation group and an ultrasound group,each with 40 cases.Patients in the manipulation group received the sitting-position knee adjustment Tuina treatment;patients in the ultrasound group received low-frequency ultrasounds for treatment.The intervention was conducted twice weekly,and therapeutic efficacy was evaluated after 4 weeks of treatment.Before treatment,immediately after treatment,and after 2-week and 4-week treatment,the visual analog scale(VAS)and the Western Ontario and McMaster Universities osteoarthritis index(WOMAC)scores were observed;the gait analysis outcomes were compared before treatment and after 4-week treatment,including cadence,speed,step length,stride length,single stance phase,double stance phase,and the maximal flexion angle of the knee joint.Results:Intra-group comparisons revealed that both groups showed decreased VAS scores and increased WOMAC scores immediately after treatment and after 2-week and 4-week treatment,with statistical significance(P<0.05).Immediately after treatment,the VAS score was lower in the manipulation group than in the ultrasound group(P<0.05),and the WOMAC pain score was higher in the manipulation group(P<0.05),while the ultrasound group had a higher WOMAC stiffness score than the manipulation group(P<0.05).After 2 weeks of treatment,there were no significant differences in VAS and WOMAC scores between the two groups(P>0.05).After 4-week treatment,the ultrasound group had a higher WOMAC pain score than the manipulation group(P<0.05),and the manipulation group had higher WOMAC stiffness and function scores than the ultrasound group(P<0.05).The between-group difference in the WOMAC total score remained statistically insignificant throughout the treatment(P>0.05).Regarding the gait parameters,both groups showed improvements in the cadence,speed,step length,stride length,single stance phase,double stance phase,swing phase,and maximal knee flexion angle immediately after treatment and after 2 and 4 weeks of treatment;the intra-group differences were all statistically significant(P<0.05).After 4-week treatment,the manipulation group surpassed the ultrasound group in improvements in stride length,step length,swing phase,single stance phase,and maximal knee flexion angle(P<0.05).Conclusion:Both the sitting-position knee adjustment Tuina and low-frequency ultrasound therapies are effective in treating KOA and can improve the patient’s walking ability;the sitting-position knee adjustment manipulation demonstrates superior immediate pain relief and long-term improvement of stiffness,joint function,and walking ability compared to the low-frequency ultrasound. 展开更多
关键词 TUINA MASSAGE Manual Therapies Ultrasonic Therapy Osteoarthritis Knee Gait analysis Randomized Controlled Trial
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Parameter optimization of the observation system for the South Yellow Sea strong shielding layer based on seismic illumination analysis 被引量:1
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作者 Yang Jia-Jia Chen Jian-Wen +5 位作者 Huang Fu-Qiang Yan Zhong-Hui Lei Bao-Hua Wang Xiao-Jie Xu Hua-Ning Liu Hong 《Applied Geophysics》 2025年第1期84-98,233,共16页
The seismic data of the Laoshan Uplift in the South Yellow Sea Basin reveal a low signal-tonoise ratio and low refl ection signal energy in the deep Mesozoic–Paleozoic strata.The main reason is that the Mesozoic-Pale... The seismic data of the Laoshan Uplift in the South Yellow Sea Basin reveal a low signal-tonoise ratio and low refl ection signal energy in the deep Mesozoic–Paleozoic strata.The main reason is that the Mesozoic-Paleozoic marine carbonate rock strata are directly covered by the Cenozoic terrestrial clastic rock strata,which form a strong shielding layer.To obtain the reflection signals of the strata below the strong shielding layer,a one-way wave equation bidirectional illumination analysis of the main observation system parameters was conducted by analyzing the mechanism of the strong shielding layer.Low-frequency seismic sources are assumed to have a high illumination intensity on the reflection layer below the strong shielding layer.Accordingly,optimized acquisition parameter suggestions were proposed,and reacquisition was performed at the existing survey line locations in the Laoshan Uplift area.The imaging of the newly acquired data in the middle and deep layers was drastically improved.It revealed the unconformity between the Sinian and Cambrian under the strong shielding layer.The study yielded new insights into the tectonic and sedimentary evolution of the Lower Paleozoic in the South Yellow Sea. 展开更多
关键词 illumination analysis acquisition parameters Laoshan Uplift strong shielding layer
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Parameter influence analysis and optimization of wheel–rail creepage characteristics in high-speed railway curves
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作者 Bolun An Jiapeng Liu +3 位作者 Guang Yang Feng shou Liu Tong Shi Ming Zhai 《Railway Sciences》 2025年第1期37-51,共15页
Purpose–To investigate the influence of vehicle operation speed,curve geometry parameters and rail profile parameters on wheel–rail creepage in high-speed railway curves and propose a multi-parameter coordinated opt... Purpose–To investigate the influence of vehicle operation speed,curve geometry parameters and rail profile parameters on wheel–rail creepage in high-speed railway curves and propose a multi-parameter coordinated optimization strategy to reduce wheel–rail contact fatigue damage.Design/methodology/approach–Taking a small-radius curve of a high-speed railway as the research object,field measurements were conducted to obtain track parameters and wheel–rail profiles.A coupled vehicle-track dynamics model was established.Multiple numerical experiments were designed using the Latin Hypercube Sampling method to extract wheel-rail creepage indicators and construct a parameter-creepage response surface model.Findings–Key service parameters affecting wheel–rail creepage were identified,including the matching relationship between curve geometry and vehicle speed and rail profile parameters.The influence patterns of various parameters on wheel–rail creepage were revealed through response surface analysis,leading to the establishment of parameter optimization criteria.Originality/value–This study presents the systematic investigation of wheel–rail creepage characteristics under multi-parameter coupling in high-speed railway curves.A response surface-based parameter-creepage relationship model was established,and a multi-parameter coordinated optimization strategy was proposed.The research findings provide theoretical guidance for controlling wheel–rail contact fatigue damage and optimizing wheel–rail profiles in high-speed railway curves. 展开更多
关键词 High-speed railway Curve track Wheel-rail creepage parameter analysis Response surface methodology Optimization design
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Transient analysis of functionally graded curved shells using a nonuniform shape parameter integrated radial basis function approach
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作者 Vay Siu Lo Andrzej Katunin Thien Tich Truong 《Theoretical & Applied Mechanics Letters》 2025年第3期296-308,共13页
In this study,an improved integrated radial basis function with nonuniform shape parameter is introduced.The proposed shape parameter varies in each support domain and is defined byθ=1/d_(max),where d_(max)is the max... In this study,an improved integrated radial basis function with nonuniform shape parameter is introduced.The proposed shape parameter varies in each support domain and is defined byθ=1/d_(max),where d_(max)is the maximum distance of any pair of nodes in the support domain.The proposed method is verified and shows good performance.The results are stable and accurate with any number of nodes and an arbitrary nodal distribution.Notably,the support domain should be large enough to obtain accurate results.This method is then applied for transient analysis of curved shell structures made from functionally graded materials with complex geometries.Through several numerical examples,the accuracy of the proposed approach is demonstrated and discussed.Additionally,the influence of various factors on the dynamic behavior of the structures,including the power-law index,different materials,loading conditions,and geometrical parameters of the structures,was investigated. 展开更多
关键词 Integrated radial basis function Shape parameter Functionally graded material Curved shell Transient analysis
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A novel porous shock absorption layer for tunnels: Shock absorption performance and parameter analysis
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作者 Zhou Tonglai Dong Changsong +1 位作者 Li Shuang Sun Qiangqiang 《Earthquake Engineering and Engineering Vibration》 2025年第2期437-450,共14页
A novel porous shock absorption layer is put forward in this study, and the shock absorption performance of the porous shock absorption layer is evaluated based on three-dimensional pseudo-static analysis. The modifie... A novel porous shock absorption layer is put forward in this study, and the shock absorption performance of the porous shock absorption layer is evaluated based on three-dimensional pseudo-static analysis. The modified reaction acceleration method is adopted and validated in the three-dimensional model. Seven ground motions are selected and the peak ground acceleration is adjusted to 0.2 g, 0.4 g and 0.6 g. The impact of the void ratio and thickness of the porous shock absorption layer is studied, while the surrounding rock grade and tunnel depth are also investigated. The numerical results show that the porous shock absorption layer has good shock absorption performance and can effectively reduce the maximum internal force of the secondary lining, but it cannot reduce the maximum horizontal relative displacement of the secondary lining. The circumferential rubber strip in the porous shock absorption layer will reduce shock absorption performance. The results of parameter analysis indicate that the shock absorption performance of the porous shock absorption layer increases with the increase of the void ratio and thickness, and it has good shock absorption performance under different surrounding rock grades and tunnel depths. 展开更多
关键词 TUNNEL porous shock absorption layer shock absorption performance reaction acceleration method parameter analysis
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Back analysis of rock mass parameters in mechanized twin tunnels based on coupled auto machine learning and multi-objective optimization algorithm
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作者 Chengwen Wang Xiaoli Liu +4 位作者 Jiubao Li Enzhi Wang Nan Hu Wenli Yao Zhihui He 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第11期7038-7055,共18页
Accurate determination of rock mass parameters is essential for ensuring the accuracy of numericalsimulations. Displacement back-analysis is the most widely used method;however, the reliability of thecurrent approache... Accurate determination of rock mass parameters is essential for ensuring the accuracy of numericalsimulations. Displacement back-analysis is the most widely used method;however, the reliability of thecurrent approaches remains unsatisfactory. Therefore, in this paper, a multistage rock mass parameterback-analysis method, that considers the construction process and displacement losses is proposed andimplemented through the coupling of numerical simulation, auto-machine learning (AutoML), andmulti-objective optimization algorithms (MOOAs). First, a parametric modeling platform for mechanizedtwin tunnels is developed, generating a dataset through extensive numerical simulations. Next, theAutoML method is utilized to establish a surrogate model linking rock parameters and displacements.The tunnel construction process is divided into multiple stages, transforming the rock mass parameterback-analysis into a multi-objective optimization problem, for which multi-objective optimization algorithmsare introduced to obtain the rock mass parameters. The newly proposed rock mass parameterback-analysis method is validated in a mechanized twin tunnel project, and its accuracy and effectivenessare demonstrated. Compared with traditional single-stage back-analysis methods, the proposedmodel decreases the average absolute percentage error from 12.73% to 4.34%, significantly improving theaccuracy of the back-analysis. Moreover, although the accuracy of back analysis significantly increaseswith the number of construction stages considered, the back analysis time is acceptable. This studyprovides a new method for displacement back analysis that is efficient and accurate, thereby paving theway for precise parameter determination in numerical simulations. 展开更多
关键词 Back analysis of rock parameters Auto machine learning Multi-objective optimization algorithm Mechanized twin tunnels Parametric modeling
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Effect of total knee arthroplasty on the spinopelvic parameters: A systemic review and metanalysis
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作者 Mantu Jain Deb Kumar Pal +3 位作者 Rabi Narayan Sahu Bikash Ranjan Meher Binod Kumar Patro Sujit Kumar Tripathy 《World Journal of Orthopedics》 2025年第7期126-133,共8页
BACKGROUND Sagittal spinopelvic alignment(SSA)is essential for preserving a stable and effective upright posture and locomotion.Although alterations in the SSA are recognised to induce compensatory modifications in th... BACKGROUND Sagittal spinopelvic alignment(SSA)is essential for preserving a stable and effective upright posture and locomotion.Although alterations in the SSA are recognised to induce compensatory modifications in the pelvis,hips,and knees,the inverse relationship concerning knee pathology undergoing total knee arthroplasty(TKA)has been examined by a limited number of studies,yielding inconclusive results.AIM To generate evidence of the effect of TKA on the SSA from existing literature.METHODS Databases like PubMed,EMBASE,and Scopus were used to identify articles related to the“knee spine syndrome”phenomenon using a combination of subject terms and keywords such as“spinopelvic parameters”,“sagittal spinal balance”,and“total knee arthroplasty”were used with appropriate Boolean operators.Studies measuring the SSA following TKA were included,and research was conducted as per preferred reporting items for systematic review and metaanalysis guidelines.RESULTS A total of 475 participants had undergone TKA,and six studies measuring SSA were analysed.Following TKA,pelvic tilt was the only parameter that showed significant changes,while lumbar lordosis(LL),pelvic incidence,and sacral slope were non-significant,as evident from the forest plots.CONCLUSION The body's sagittal alignment is a complex balance between pelvic,spine,and lower extremity parameters.TKA,while having the potential to correct the flexion contracture,can also correct it.Still,the primary SSA for spinal pathology,i.e.,LL,may not be corrected in patients with co-existent spinal degenerative disease. 展开更多
关键词 Spinopelvic parameters Total knee arthroplasty Pelvic parameters Lower extremities parameters META-analysis
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Analysis and estimation of wave-induced Doppler shift from low-incidence-angle RAR based on sea state parameters
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作者 Jing Ye Yong Wan +3 位作者 Chenqing Fan Yongshou Dai Yisen Yang Xiangying Miao 《Acta Oceanologica Sinica》 2025年第9期169-182,共14页
The research on ocean dynamics information plays a crucial role in understanding ocean phenomena, assessing marine environmental impacts, and guiding engineering designs. The Doppler information observed by radars ref... The research on ocean dynamics information plays a crucial role in understanding ocean phenomena, assessing marine environmental impacts, and guiding engineering designs. The Doppler information observed by radars reflects sea surface dynamics, to which ocean waves make important contributions. Low-incidence-angle real aperture radar(RAR)demonstrates great potential for independently observing vectorial Doppler information on the ocean surface. To systematically characterize and accurately estimate the wave-induced Doppler frequency shift(WVF) from lowincidence-angle RAR, this study conducts comprehensive influencing factor analysis and establishes sea-stateparameterized WVF models. First, a simulated WVF dataset is generated under a rotating low-incidence-angle RAR.The feature parameters of WVF are then determined by analysing contributing factors including wind waves, swells,and sea state parameters. Furthermore, two WVF models(WVF_Ku P9 with 9 inputs and WVF_Ku P4 with 4 inputs) are constructed by the Transformer encoder for different application scenarios. Both models achieve high accuracy for WVF estimation with root mean square errors(RMSE) of 1.874 Hz and 2.716 Hz, respectively. The reliability and superiority of the proposed models are validated through comparisons with the Ka DOP, which is a typical geophysical model function(GMF). The findings in this paper advance the understanding of WVF characteristics and generation mechanisms. The proposed estimation models can provide reliable estimates, offering critical references for lowincidence-angle RAR applications such as ocean surface current retrieval. 展开更多
关键词 wave-induced Doppler shift parameter estimation low-incidence-angle real aperture radar sea state parameters Transformer encoder
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Micronucleus counts correlating with male infertility:a clinical analysis of chromosomal abnormalities and reproductive parameters
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作者 Shun-Han Zhang Ying-Jun Xie +6 位作者 Wen-Jun Qiu Qian-Ying Pan Li-Hao Chen Jian-Feng Wu Si-Qi Huang Ding Wang Xiao-Fang Sun 《Asian Journal of Andrology》 2025年第4期537-542,共6页
Investigating the correlation between micronucleus formation and male infertility has the potential to improve clinical diagnosis and deepen our understanding of pathological progression. Our study enrolled 2252 male ... Investigating the correlation between micronucleus formation and male infertility has the potential to improve clinical diagnosis and deepen our understanding of pathological progression. Our study enrolled 2252 male patients whose semen was analyzed from March 2023 to July 2023. Their clinical data, including semen parameters and age, were also collected. Genetic analysis was used to determine whether the sex chromosome involved in male infertility was abnormal (including the increase, deletion, and translocation of the X and Y chromosomes), and subsequent semen analysis was conducted for clinical grouping purposes. The participants were categorized into five groups: normozoospermia, asthenozoospermia, oligozoospermia, oligoasthenozoospermia, and azoospermia. Patients were randomly selected for further study;41 patients with normozoospermia were included in the control group and 117 patients with non-normozoospermia were included in the study group according to the proportions of all enrolled patients. Cytokinesis-block micronucleus (CBMN) screening was conducted through peripheral blood. Statistical analysis was used to determine the differences in micronuclei (MNi) among the groups and the relationships between MNi and clinical data. There was a significant increase in MNi in infertile men, including those with azoospermia, compared with normozoospermic patients, but there was no significant difference between the genetic and nongenetic groups in azoospermic men. The presence of MNi was associated with sperm concentration, progressive sperm motility, immotile spermatozoa, malformed spermatozoa, total sperm count, and total sperm motility. This study underscores the potential utility of MNi as a diagnostic tool and highlights the need for further research to elucidate the underlying mechanisms of male infertility. 展开更多
关键词 chromosome instability genetic azoospermia male infertility MICRONUCLEUS semen parameters
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Real-time operational parameter recommendation system for tunnel boring machines:Application and performance analysis
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作者 WANG Shuangjing WU Leijie LI Xu 《Journal of Mountain Science》 2025年第5期1819-1831,共13页
The accurate selection of operational parameters is critical for ensuring the safety,efficiency,and automation of Tunnel Boring Machine(TBM)operations.This study proposes a similarity-based framework integrating model... The accurate selection of operational parameters is critical for ensuring the safety,efficiency,and automation of Tunnel Boring Machine(TBM)operations.This study proposes a similarity-based framework integrating model-based boring indexes(derived from rock fragmentation mechanisms)and Euclidean distance analysis to achieve real-time recommendations of TBM operational parameters.Key performance indicators-thrust(F),torque(T),and penetration(p)-were used to calculate three model-based boring indexes(a,b,k),which quantify dynamic rock fragmentation behavior.A dataset of 359 candidate samples,reflecting diverse geological conditions from the Yin-Chao water conveyance project in Inner Mongolia,China,was utilized to validate the framework.The system dynamically recommends parameters by matching real-time data with historical cases through standardized Euclidean distance,achieving high accuracy.Specifically,the mean absolute error(MAE)for rotation speed(n)was 0.10 r/min,corresponding to a mean absolute percentage error(MAPE)of 1.09%.For advance rate(v),the MAE was 3.4 mm/min,with a MAPE of 4.50%.The predicted thrust(F)and torque(T)values exhibited strong agreement with field measurements,with MAEs of 270 kN and 178 kN∙m,respectively.Field applications demonstrated a 30%reduction in parameter adjustment time compared to empirical methods.This work provides a robust solution for real-time TBM control,advancing intelligent tunneling in complex geological environments. 展开更多
关键词 Tunnel Boring Machine Similarity based method Boring indexes Operational parameters Realtime recommendation
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Analysis of phacoemulsification parameters and anterior segment parameters in cataract patients with different blood glucose levels
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作者 Xu Xinqi Wang Ping +5 位作者 Liu Tong Wang Lei Zhu Xuansheng Zhang Huiwen Shi Lei Gao Wen 《国际眼科杂志》 2025年第6期875-885,共11页
AIM:To analyze the characteristics and correlation of phacoemulsification parameters and anterior segment parameters in cataract patients with different blood glucose levels.METHODS:A total of 45 type 2 diabetic catar... AIM:To analyze the characteristics and correlation of phacoemulsification parameters and anterior segment parameters in cataract patients with different blood glucose levels.METHODS:A total of 45 type 2 diabetic cataract patients(45 eyes)treated in our hospital from March 2023 to April 2024 were stratified into two groups based on glycosylated hemoglobin(HbA1c)levels:group A:HbA1c<7%(n=18)and group B:7%≤HbA1c<8.5%(n=27);a total of 94 age-matched age-related cataract patients(94 eyes)were enrolled as the control group(group C).All underwent phacoemulsification with intraocular lens implantation.Anterior segment parameters,including corneal,lens and anterior chamber measurements,were recorded.Correlations between phacoemulsification parameters and anterior segment parameters were analyzed,and differences among groups were compared.RESULTS:In groups A and B,effective phacoemulsification time(EPT)negatively correlated with corneal endothelial cell density(CECD)(r=-0.315,P=0.035).Average phacoemulsification time(APT)positively correlated with the anterior corneal surface radius of curvature(Rm;r=0.402,P=0.006)and negatively correlated with the flat axis meridian curvature(K 1),steep axis meridian curvature(K 2),mean curvature(Km)of the anterior corneal surface,and lens density at 6 mm zones(PDZ3;all P<0.05).Average phacoemulsification energy(AVE)positively correlated with mean lens density(LD-mean),lens density at 2 mm zones(PDZ1),lens density at 4 mm zones(PDZ2),and PDZ3(all P<0.05),and negatively with pupil diameter(r=-0.385,P=0.009).In the group C,EPT showed a positive correlation with Pentacam nucleus staging(PNS)density grade,PDZ1,PDZ2,and PDZ3(all P<0.05).A positive correlation was observed between AVE and PNS classification(r=0.246,P=0.018).Conversely,AVE exhibited a negative correlation with CECD(r=-0.245,P=0.018).EPT in groups A and B was higher than that in the group C(P<0.05).Both EPT and APT in the group B were higher than those in the group A(P<0.05).In diabetic cataract patients,CECD,corneal density(CD),and posterior corneal surface height positively correlated with diabetes duration(P<0.05).Posterior corneal surface K 1 and Rm positively correlated with 7%≤HbA1c<8.5%(P<0.05).Total corneal astigmatism negatively correlated with HbA1c,2-hour post-breakfast blood glucose(2hPBG),and fasting insulin(FINS;P<0.05).CD and lens thickness(LT)positively correlated with FINS(P<0.05).CONCLUSION:Phacoemulsification parameters and blood glucose-related indices exhibited varying degrees of correlation with anterior segment parameters in cataract patients with different blood glucose levels.EPT in diabetic cataract patients was higher than that in age-related cataract patients,while EPT and APT in diabetic cataract patients with poor glycemic control were higher than those with good glycemic control. 展开更多
关键词 diabetic cataract effective phacoemulsification time average phacoemulsification energy average phacoemulsification time anterior segment parameter
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Changes in border-associated macrophages after stroke: Single-cell sequencing analysis 被引量:2
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作者 Ning Yu Yang Zhao +3 位作者 Peng Wang Fuqiang Zhang Cuili Wen Shilei Wang 《Neural Regeneration Research》 2026年第1期346-356,共11页
Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macro... Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macrophages have been poorly understood and largely overlooked. However, a recent study reported that border-associated macrophages participate in stroke-induced inflammation, although many details and the underlying mechanisms remain unclear. In this study, we performed a comprehensive single-cell analysis of mouse border-associated macrophages using sequencing data obtained from the Gene Expression Omnibus(GEO) database(GSE174574 and GSE225948). Differentially expressed genes were identified, and enrichment analysis was performed to identify the transcription profile of border-associated macrophages. CellChat analysis was conducted to determine the cell communication network of border-associated macrophages. Transcription factors were predicted using the ‘pySCENIC' tool. We found that, in response to hypoxia, borderassociated macrophages underwent dynamic transcriptional changes and participated in the regulation of inflammatory-related pathways. Notably, the tumor necrosis factor pathway was activated by border-associated macrophages following ischemic stroke. The pySCENIC analysis indicated that the activity of signal transducer and activator of transcription 3(Stat3) was obviously upregulated in stroke, suggesting that Stat3 inhibition may be a promising strategy for treating border-associated macrophages-induced neuroinflammation. Finally, we constructed an animal model to investigate the effects of border-associated macrophages depletion following a stroke. Treatment with liposomes containing clodronate significantly reduced infarct volume in the animals and improved neurological scores compared with untreated animals. Taken together, our results demonstrate comprehensive changes in border-associated macrophages following a stroke, providing a theoretical basis for targeting border-associated macrophages-induced neuroinflammation in stroke treatment. 展开更多
关键词 border-associated macrophages CLODRONATE hypoxia ISCHEMIA-REPERFUSION ischemic stroke liposomes neuroinflammation single-cell sequencing analysis STAT3 tumor necrosis factor
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Model’s parameter sensitivity assessment and their impact on Urban Densification using regression analysis
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作者 Anasua Chakraborty Mitali Yeshwant Joshi +2 位作者 Ahmed Mustafa Mario Cools Jacques Teller 《Geography and Sustainability》 2025年第2期143-156,共14页
The impact of different global and local variables in urban development processes requires a systematic study to fully comprehend the underlying complexities in them.The interplay between such variables is crucial for... The impact of different global and local variables in urban development processes requires a systematic study to fully comprehend the underlying complexities in them.The interplay between such variables is crucial for modelling urban growth to closely reflects reality.Despite extensive research,ambiguity remains about how variations in these input variables influence urban densification.In this study,we conduct a global sensitivity analysis(SA)using a multinomial logistic regression(MNL)model to assess the model’s explanatory and predictive power.We examine the influence of global variables,including spatial resolution,neighborhood size,and density classes,under different input combinations at a provincial scale to understand their impact on densification.Additionally,we perform a stepwise regression to identify the significant explanatory variables that are important for understanding densification in the Brussels Metropolitan Area(BMA).Our results indicate that a finer spatial resolution of 50 m and 100 m,smaller neighborhood size of 5×5 and 3×3,and specific density classes—namely 3(non-built-up,low and high built-up)and 4(non-built-up,low,medium and high built-up)—optimally explain and predict urban densification.In line with the same,the stepwise regression reveals that models with a coarser resolution of 300 m lack significant variables,reflecting a lower explanatory power for densification.This approach aids in identifying optimal and significant global variables with higher explanatory power for understanding and predicting urban densification.Furthermore,these findings are reproducible in a global urban context,offering valuable insights for planners,modelers and geographers in managing future urban growth and minimizing modelling. 展开更多
关键词 Urban densification Sensitivity analysis Multinomial logistic regression Stepwise regression
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Optimization of the key parameters in the carrot seed guiding system using DEM-CFD analysis
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作者 Yue Sun Lianglong Zhang +2 位作者 Fan Yang Fangyan Wang Jingtao Jiang 《International Journal of Agricultural and Biological Engineering》 2025年第6期112-121,共10页
The objective of this research was to enhance the stability and consistency of seed distribution during carrot planting.The impact of the seed guide tube’s structure on seeding quality was examined,leading to the des... The objective of this research was to enhance the stability and consistency of seed distribution during carrot planting.The impact of the seed guide tube’s structure on seeding quality was examined,leading to the design of a cycloidal seed guide system augmented by positive pressure airflow.By conducting kinematic modeling of the collision position of the seeds within the seed guiding system,as well as considering the seed guiding process and the seed drop position,the significant parameters influencing the final velocity of the seeds were determined.Employing a coupled Discrete Element Method-Computational Fluid Dynamics(DEM-CFD)simulation,the effects of different structural and operating parameters of the seed guide tube on the seed trajectory and airflow field were analyzed.A three-factor five-level orthogonal test was then utilized to examine the influence of each factor on each index,with the optimal conditions identified as an inlet airflow velocity of 0.077 m/s,a 45°tilt angle for the airflow branch tube,and a seed initial velocity of 0.1 m/s.Under these parameters,the qualification index was recorded as 94.1%,with a coefficient of variation of 3.2%.Bench testing conducted under the same conditions showed a decrease of 0.07%in the qualification index,and an increase of 1.875%in the coefficient of variation,with errors relative to the simulation results within acceptable bounds.These findings enhance the stability and reliability of the seed guiding system during carrot sowing operations,aligning with the demands of precision sowing. 展开更多
关键词 CARROT seed guiding process seed motion analysis air assisted DEM-CFD
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Parameter sensitivity analysis and optimization of carbon and water fluxes in grassland ecosystems based on the Biome-BGCMuSo Model
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作者 TIAN Yujie JING Changqing +2 位作者 SHAO Yuqing WANG Xiaoyi ZHU Yuhao 《Journal of Mountain Science》 2025年第11期3964-3977,共14页
Accurate quantification of carbon and water fluxes dynamics in arid and semi-arid ecosystems is a critical scientific challenge for regional carbon neutrality assessments and sustainable water resource management.In t... Accurate quantification of carbon and water fluxes dynamics in arid and semi-arid ecosystems is a critical scientific challenge for regional carbon neutrality assessments and sustainable water resource management.In this study,we developed a multi-flux global sensitivity discriminant index(D_(sen))by integrating the Biome-BGCMuSo model with eddy covariance flux observations.This index was combined with a Bayesian optimization algorithm to conduct parameter optimization.The results demonstrated that:(1)Sensitivity analysis identified 13 highly sensitive parameters affecting carbon and water fluxes.Among these,the canopy light extinction coefficient(k)and the fraction of leaf N in Rubisco(FLNR)exhibited significantly higher sensitivity to carbon fluxes(GPP,NEE,Reco;D_(sen)>10%)compared to water flux(ET).This highlights the strong dependence of carbon cycle simulations on vegetation physiological parameters.(2)The Bayesian optimization framework efficiently converged 30 parameter spaces within 50 iterations,markedly improving carbon fluxes simulation accuracy.The Kling-Gupta efficiency(KGE)values for Gross Primary Production(GPP),Net Ecosystem Exchange(NEE),and Total Respiration(Reco)increased by 44.94%,69.23%and 123%,respectively.The optimization prioritized highly sensitive parameters,underscoring the necessity of parameter sensitivity stratification.(3)The optimized model effectively reproduced carbon sink characteristics in mountain meadows during the growing season(cumulative NEE=-375 g C/m^(2)).It revealed synergistic carbon-water fluxes interactions governed by coupled photosynthesis-stomatal pathways and identified substrate supply limitations on heterotrophic respiration.This study proposes a novel multi-flux sensitivity index and an efficient optimization framework,elucidating the coupling mechanisms between vegetation physiological regulation(k,FLNR)and environmental stressors(VPD,SWD)in carbonwater cycles.The methodology offers a practical approach for arid ecosystem model optimization and provides theoretical insights for grassland management through canopy structure regulation and water-use efficiency enhancement. 展开更多
关键词 Carbon flux Water flux Biome-BGCMuSo model Sensitivity analysis Bayesian optimization Grassland ecosystems
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Statistics and Development Analysis of Urban Rail Transit in China by the End of 2025
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作者 WANG Fuwen LIANG Shuaiwen FENG Aijun 《隧道建设(中英文)》 北大核心 2026年第2期437-444,I0005-I0012,共16页
First,statistics on the operational lines and mileage of urban rail transit in China are conducted.The results show that,as of Dec.31,2025,there were 60 cities with urban rail transit in operation nationwide,with a to... First,statistics on the operational lines and mileage of urban rail transit in China are conducted.The results show that,as of Dec.31,2025,there were 60 cities with urban rail transit in operation nationwide,with a total operational mileage of approximately 12837.8 km(excluding the electronic guideway rubber-tired system,there were 57 cities,with a total operational mileage of 12651.6 km).The metro system dominates,while low-capacity systems exhibit a multi-modal development pattern.Subsequently,the characteristics of China′s urban rail transit industry development are analyzed,indicating that:(1)It should closely align with the theme of urban intensive development,promote quality improvement and efficiency enhancement of existing lines,and focus on the supporting role of initial passenger flow for new line construction,multi-network integration,and economic and financial sustainability.(2)Significant innovative achievements have been made in safety resilience,green and low-carbon development,intelligent construction,and digital transformation.Finally,development recommendations for the"15th Five-Year Plan"period are proposed:promoting cost reduction and efficiency improvement in the rail transit industry,enhancing the operational efficiency of existing networks,continuously exploring railway services for urban commuting,strengthening external exchanges,and driving the"going global"strategy of the urban rail transit industry. 展开更多
关键词 rail transit operational lines data statistics development analysis
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Crystal structure,thermal analysis,and luminescence properties of six heterocyclic lanthanide complexes
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作者 SONG Zihe ZHAO Jinjin +1 位作者 REN Ning ZHANG Jianjun 《无机化学学报》 北大核心 2026年第1期181-192,共12页
Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'... Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6. 展开更多
关键词 lanthanide complexes fluorescence property crystal structure thermal analysis
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A logistic-Lasso-regression-based seismic fragility analysis method for electrical equipment considering structural and seismic parameter uncertainty
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作者 Cui Jiawei Che Ailan +1 位作者 Li Sheng Cheng Yongfeng 《Earthquake Engineering and Engineering Vibration》 2025年第1期169-186,共18页
Damage to electrical equipment in an earthquake can lead to power outage of power systems.Seismic fragility analysis is a common method to assess the seismic reliability of electrical equipment.To further guarantee th... Damage to electrical equipment in an earthquake can lead to power outage of power systems.Seismic fragility analysis is a common method to assess the seismic reliability of electrical equipment.To further guarantee the efficiency of analysis,multi-source uncertainties including the structure itself and seismic excitation need to be considered.A method for seismic fragility analysis that reflects structural and seismic parameter uncertainty was developed in this study.The proposed method used a random sampling method based on Latin hypercube sampling(LHS)to account for the structure parameter uncertainty and the group structure characteristics of electrical equipment.Then,logistic Lasso regression(LLR)was used to find the seismic fragility surface based on double ground motion intensity measures(IM).The seismic fragility based on the finite element model of an±1000 kV main transformer(UHVMT)was analyzed using the proposed method.The results show that the seismic fragility function obtained by this method can be used to construct the relationship between the uncertainty parameters and the failure probability.The seismic fragility surface did not only provide the probabilities of seismic damage states under different IMs,but also had better stability than the fragility curve.Furthermore,the sensitivity analysis of the structural parameters revealed that the elastic module of the bushing and the height of the high-voltage bushing may have a greater influence. 展开更多
关键词 seismic fragility UNCERTAINTY logistic lasso regression ±1000 kV main transformer sensitivity analysis
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Prediction and Comparative Analysis of Rooftop PV Solar Energy Efficiency Considering Indoor and Outdoor Parameters under Real Climate Conditions Factors with Machine Learning Model
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作者 Gokhan Sahin Ihsan Levent +2 位作者 Gültekin Isik Wilfriedvan Sark Sabir Rustemli 《Computer Modeling in Engineering & Sciences》 2025年第4期1215-1248,共34页
This research investigates the influence of indoor and outdoor factors on photovoltaic(PV)power generation at Utrecht University to accurately predict PV system performance by identifying critical impact factors and i... This research investigates the influence of indoor and outdoor factors on photovoltaic(PV)power generation at Utrecht University to accurately predict PV system performance by identifying critical impact factors and improving renewable energy efficiency.To predict plant efficiency,nineteen variables are analyzed,consisting of nine indoor photovoltaic panel characteristics(Open Circuit Voltage(Voc),Short Circuit Current(Isc),Maximum Power(Pmpp),Maximum Voltage(Umpp),Maximum Current(Impp),Filling Factor(FF),Parallel Resistance(Rp),Series Resistance(Rs),Module Temperature)and ten environmental factors(Air Temperature,Air Humidity,Dew Point,Air Pressure,Irradiation,Irradiation Propagation,Wind Speed,Wind Speed Propagation,Wind Direction,Wind Direction Propagation).This study provides a new perspective not previously addressed in the literature.In this study,different machine learning methods such as Multilayer Perceptron(MLP),Multivariate Adaptive Regression Spline(MARS),Multiple Linear Regression(MLR),and Random Forest(RF)models are used to predict power values using data from installed PVpanels.Panel values obtained under real field conditions were used to train the models,and the results were compared.The Multilayer Perceptron(MLP)model was achieved with the highest classification accuracy of 0.990%.The machine learning models used for solar energy forecasting show high performance and produce results close to actual values.Models like Multi-Layer Perceptron(MLP)and Random Forest(RF)can be used in diverse locations based on load demand. 展开更多
关键词 Machine learning model multi-layer perceptrons(MLP) random forest(RF) solar photovoltaic panel energy efficiency indoor and outdoor parameters forecasting
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