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Steady‑state microbunching based on transverse‑longitudinal coupling
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作者 Xiu‑Jie Deng Alexander Wu Chao +3 位作者 Wen‑Hui Huang Zi‑Zheng Li Zhi‑Long Pan Chuan‑Xiang Tang 《Nuclear Science and Techniques》 2026年第1期1-49,共49页
In this study,three specific scenarios of a novel accelerator light source mechanism called steady-state microbunching(SSMB)were studied:longitudinal weak focusing,longitudinal strong focusing,and generalized longitud... In this study,three specific scenarios of a novel accelerator light source mechanism called steady-state microbunching(SSMB)were studied:longitudinal weak focusing,longitudinal strong focusing,and generalized longitudinal strong focusing(GLSF).At present,GLSF is the most promising method for realizing high-power short-wavelength coherent radiation with mild requirements on modulation laser power.Its essence is to exploit the ultrasmall natural vertical emittance of an electron beam in a planar storage ring for efficient microbunching formation,like a partial transverse-longitudinal emittance exchange in the optical laser wavelength range.Based on an in-depth investigation of related beam physics,a solution for a GLSF SSMB storage ring that can deliver 1 kW average-power EUV light is presented.The work in this paper,such as the generalized Courant–Snyder formalism,analysis of theoretical minimum emittances,transverse-longitudinal coupling dynamics,and derivation of the bunching factor and modulation strengths for laser-induced microbunching schemes,is expected to be useful not only for the development of SSMB but also for future accelerator light sources in general that demand increasingly precise electron beam phase space manipulations. 展开更多
关键词 Steady-state microbunching Extreme ultraviolet ARPES Generalized Courant-Snyder formalism Theoretical minimum emittances longitudinal weak focusing longitudinal strong focusing Generalized longitudinal strong focusing Transverse-longitudinal coupling Damping wiggler
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Longitudinal trajectory analysis of sepsis after laparoscopic surgery
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作者 Boming Xia Chengqiao Jiang +9 位作者 Jie Yang Suibi Yang Bo Zhang Zhihao Wang Shengze Wu Yang Wang Qian Gao Yucai Hong Huiqing Ge Zhongheng Zhang 《Laparoscopic, Endoscopic and Robotic Surgery》 2026年第1期34-51,共18页
Objective:Sepsis exhibits remarkable heterogeneity in disease progression trajectories,and accurate identificationof distinct trajectory-based phenotypes is critical for implementing personalized therapeutic strategie... Objective:Sepsis exhibits remarkable heterogeneity in disease progression trajectories,and accurate identificationof distinct trajectory-based phenotypes is critical for implementing personalized therapeutic strategies and prognostic assessment.However,trajectory clustering analysis of time-series clinical data poses substantial methodological challenges for researchers.This study provides a comprehensive tutorial framework demonstrating six trajectory modeling approaches integrated with proteomic analysis to guide researchers in identifying sepsis subtypes after laparoscopic surgery.Methods:This study employs simulated longitudinal data from 300 septic patients after laparoscopic surgery to demonstrate six trajectory modeling methods(group-based trajectory modeling,latent growth mixture modeling,latent transition analysis,time-varying effect modeling,K-means for longitudinal data,agglomerative hierarchical clustering)for identifying associations between predefinedsequential organ failure assessment trajectories and 25 proteomic biomarkers.Clustering performance was evaluated via multiple metrics,and a biomarker discovery pipeline integrating principal component analysis,random forests,feature selection,and receiver operating characteristic analysis was developed.Results:The six methods demonstrated varying performance in identifying trajectory structures,with each approach exhibiting distinct analytical characteristics.The performance metrics revealed differences across methods,which may inform context-specificmethod selection and interpretation strategies.Conclusion:This study illustrates practical implementations of trajectory modeling approaches under controlled conditions,facilitating informed method selection for clinical researchers.The inclusion of complete R code and integrated proteomics workflows offers a reproducible analytical framework connecting temporal pattern recognition to biomarker discovery.Beyond sepsis,this pipeline-oriented approach may be adapted to diverse clinical scenarios requiring longitudinal disease characterization and precision medicine applications.The comparative analysis reveals that each method has distinct strengths,providing a practical guide for clinical researchers in selecting appropriate methods based on their specificstudy goals and data characteristics. 展开更多
关键词 Laparoscopic surgery SEPSIS longitudinal trajectory Group-based trajectory modeling Latent class analysis PHENOTYPING
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Analytical solution for longitudinal responses of tunnels under combined effects of seismic waves and strike-slip faulting
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作者 Jie Tang Manchao He +2 位作者 Yafei Qiao Hanbing Bian Chun Zhu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1266-1289,共24页
Strong seismic excitation and fault dislocation are likely to occur simultaneously in high-intensity seismic zones,causing severe damage to tunnels crossing active fault zones.This paper aims to develop a novel analyt... Strong seismic excitation and fault dislocation are likely to occur simultaneously in high-intensity seismic zones,causing severe damage to tunnels crossing active fault zones.This paper aims to develop a novel analytical solution to determine the longitudinal mechanical responses of tunnels subjected to the combined effects of seismic waves and strike-slip faulting.Adopting the elastic springbeam model,the seismic waves are modelled as shear horizontal(SH)waves and the fault dislocation follows an S-shaped pattern;the superposition principle for free-fielddisplacements caused by both effects is assumed.In addition,the transmission and reflectionof seismic waves at the fault-rock geological interface and the tangential contact conditions at the tunnel-rock interface are considered.The analytical model is validated against numerical simulations,confirmingits accuracy in calculating tunnel responses.Moreover,a parametric study is conducted to evaluate the impact of key factors,including fault displacement,fault zone width,fault dip angle,earthquake frequency,rock conditions,tunnel lining stiffness,and tangential contact conditions,on tunnel responses.Compared with each effect alone,the combined effects of seismic waves and strike-slip faulting significantlychange the tunnel deformation and internal forces,leading to increased tunnel responses,especially within the fault zone and near the fault-rock interfaces.Depending on specificparameters,tunnel responses can be classifiedinto seismic-dominated,faulting-dominated,and seismic-faulting coupled responses on the basis of the relative contributions of each effect.The proposed analytical solution can be applied to quickly predict the longitudinal mechanical behaviour of tunnels under such combined effects in engineering applications. 展开更多
关键词 Strike-slip faulting longitudinal tunnel response Analytical solution Seismic waves Wave transmissions and reflections
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Preliminary Design and Application of a Longitudinal Trajectory Model for Prognosis of Intracerebral Hemorrhage Based on Blood Urea Nitrogen Characteristics
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作者 GUO Dong-bin QI Xiao-long HUANG Jun-long 《Chinese Journal of Biomedical Engineering(English Edition)》 2025年第3期118-124,共7页
Objective:To preliminarily construct and apply a longitudinal trajectory model for the prognosis of intracerebral hemorrhage(ICH)based on blood urea nitrogen(BUN)characteristics.Methods:Clinical data from 320 ICH pati... Objective:To preliminarily construct and apply a longitudinal trajectory model for the prognosis of intracerebral hemorrhage(ICH)based on blood urea nitrogen(BUN)characteristics.Methods:Clinical data from 320 ICH patients admitted to our hospital between 2020 and 2024 were collected,including demographic information,National Institutes of Health Stroke Scale(NIHSS)scores at admission,dynamic changes in BUN levels during treatment,and 30-day survival outcomes.A latent class growth model(LCGM)was first used for preliminary modeling,followed by a latent growth mixture modeling(GMM)approach to determine the final model.Three classes of BUN trajectories for ICH prognosis were identified,and latent classes were established.GMM modeling was then performed on these latent classes,considering linear,quadratic,and cubic polynomial forms;six GMM models were constructed and individuals were assigned to latent trajectory groups for validation.Results:LCGM analysis ultimately identified three dynamic BUN trajectory groups:Sustained low-level group(76 cases,23.8%):BUN remained stable between 3.1-9.0 mmol/L,with the highest 30-day survival rate(98.7%).Fluctuating-declining group(222 cases,69.4%):BUN initially increased and then slowly decreased(peak at day 3:15.2 mmol/L),with a 30-day mortality of 8.1%(18/222),higher than the sustained low-level group.Sustained high-level group(22 cases,6.9%):BUN mean>9.0 mmol/L,with a 30-day mortality of 41.7%(P=0.000).GMM model fitting showed that the cubic polynomial GMM model was optimal(AIC=6754.474,BIC=6852.450,Entropy=0.905).Incorporating gender,age,and BMI as covariates revealed significant effects for gender(Estimate=0.045,-0.011,P=0.000,0.000).The AUC for predicting 30-day mortality was 0.88(sensitivity 82.8%,specificity 77.9%),which increased to 0.89 when combined with admission NIHSS scores.Conclusion:The LCGM+GMM model based on dynamic BUN trajectories effectively distinguishes prognostic subgroups in ICH patients.Patients with persistently elevated or fluctuating-rising BUN levels have a significantly higher mortality risk compared to those with sustained low levels.This model provides a new quantitative tool for early identification of high-risk patients and poor prognoses. 展开更多
关键词 Blood urea nitrogen construct apply longitudinal trajectory model intracerebral hemorrhage ich based longitudinal trajectory model Intracerebral hemorrhage Latent growth mixture modeling PROGNOSIS latent class growth model lcgm
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Longitudinal combustion instability in a hypergolic liquid bipropellant combustor with single dual-swirl coaxial injector 被引量:1
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作者 Wei CHU Kangkang GUO +3 位作者 Yiheng TONG Yongjie REN Boqi XU Wansheng NIE 《Chinese Journal of Aeronautics》 2025年第3期280-291,共12页
Self-excited longitudinal combustion instabilities were investigated in a hypergolic liquid bipropellant combustor, which applied single dual-swirl coaxial injector. Hot-fire tests were conducted for four different in... Self-excited longitudinal combustion instabilities were investigated in a hypergolic liquid bipropellant combustor, which applied single dual-swirl coaxial injector. Hot-fire tests were conducted for four different injector geometries, while extensive tests on injection conditions were carried out for each injector geometry. The synchronous measurement of the pressure and heat release rate was applied, successfully capturing the process of the pressure and heat release rate enhanced coupling and developing into in-phase oscillation. By calculating Rayleigh index at the head and middle section of the chamber, it is shown that Rayleigh index of the middle section is even higher than that of the head, indicating a long heat release zone. When the combustion instability occurs, the pressure in propellant manifolds also oscillates with the same frequency and lags behind the oscillation in the combustor. Compared to the oscillation in the outer injector manifold, the oscillation in the inner injector manifold shows a higher correlation with that in the chamber in amplitude and phase. Based on numerical simulations of the multiphase cold flow inside the injector and combustion process in the chamber, it is found that injector geometries affect longitudinal combustion instability by changing spray cone angle. The spray with small cone angle is more sensitive to the modulation of longitudinal pressure wave in combustion simulations, which is more likely to excite the longitudinal combustion instability. Meanwhile, the combustion instability may be related to the pulsating coherent structure generated by the spray fluctuation, which is determined by injection conditions. Besides, a positive feedback closed-loop system associated with the active fluctuation and passive oscillation of the spray is believed to excite and sustain the longitudinal combustion instability. 展开更多
关键词 longitudinal combustion instability Dual-swirl coaxial injector Unsymmetrical Dimethylhydrazine/Nitrogen Tetroxide(UDMH/NTO) Photomultiplier Tubes(PMT) Spray fluctuation Pressure wave Modulation
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Relationship between longitudinal changes in lipid composition and ischemic stroke among hypertensive patients
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作者 Cheng-Cheng Wei Yu-Qing Huang Cheng-Hong Yu 《World Journal of Clinical Cases》 SCIE 2025年第4期18-27,共10页
BACKGROUND Dyslipidemia was strongly linked to stroke,however the relationship between dyslipidemia and its components and ischemic stroke remained unexplained.AIM To investigate the link between longitudinal changes ... BACKGROUND Dyslipidemia was strongly linked to stroke,however the relationship between dyslipidemia and its components and ischemic stroke remained unexplained.AIM To investigate the link between longitudinal changes in lipid profiles and dyslipidemia and ischemic stroke in a hypertensive population.METHODS Between 2013 and 2014,6094 hypertension individuals were included in this,and ischemic stroke cases were documented to the end of 2018.Longitudinal changes of lipid were stratified into four groups:(1)Normal was transformed into normal group;(2)Abnormal was transformed into normal group;(3)Normal was transformed into abnormal group;and(4)Abnormal was transformed into abnormal group.To examine the link between longitudinal changes in dyslipidemia along with its components and the risk of ischemic stroke,we utilized multivariate Cox proportional hazards models with hazard ratio(HR)and 95%CI.RESULTS The average age of the participants was 62.32 years±13.00 years,with 329 women making up 54.0%of the sample.Over the course of a mean follow-up of 4.8 years,143 ischemic strokes happened.When normal was transformed into normal group was used as a reference,after full adjustments,the HR for dyslipidemia and ischemic stroke among abnormal was transformed into normal group,normal was transformed into abnormal group and abnormal was transformed into abnormal Wei CC et al.Dyslipidemia changed and ischemic stroke WJCC https://www.wjgnet.com 2 February 6,2025 Volume 13 Issue 4 group were 1.089(95%CI:0.598-1.982;P=0.779),2.369(95%CI:1.424-3.941;P<0.001)and 1.448(95%CI:1.002-2.298;P=0.047)(P for trend was 0.233),respectively.CONCLUSION In individuals with hypertension,longitudinal shifts from normal to abnormal in dyslipidemia-particularly in total and low-density lipoprotein cholesterol-were significantly associated with the risk of ischemic stroke. 展开更多
关键词 longitudinal change HYPERTENSION DYSLIPIDEMIA Lipid profile Ischemic stroke
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Longitudinal study of peer bullying victimization and its psychological effects on adolescents
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作者 Yu-Ping Bai Hao Yuan +2 位作者 Qing-Yun Yu Lu-Ming Liu Wen-Chao Wang 《World Journal of Psychiatry》 2025年第5期164-172,共9页
BACKGROUND Peer bullying victimization(PBV)is a significant public health issue that adolescents often face,with approximately one-third having experienced PBV.Understanding its interrelationships with mental health p... BACKGROUND Peer bullying victimization(PBV)is a significant public health issue that adolescents often face,with approximately one-third having experienced PBV.Understanding its interrelationships with mental health problems is crucial for effective intervention.This study aims to examine the longitudinal relationships between internalizing problems(depression and anxiety),externalizing problems(aggression),and PBV among middle school students using cross-lagged panel network analysis.AIM To examine the longitudinal relationships between internalizing problems(depression and anxiety),externalizing problems(aggression),and PBV among middle school students using cross-lagged panel network analysis.METHODS A total of 1260 middle school students(54.6%male)participated in this study.Data were collected at two time points(time 1 and time 2)using self-report questionnaires to assess PBV,depression,anxiety,and aggression.Cross-lagged panel network analysis was applied to examine the bi-directional relationships between these variables over time.RESULTS Depression,particularly a“sad mood,”was the most significant predictor of both PBV and aggression.Cyberbullying victimization also emerged as a key factor influencing depression and anxiety.While anxiety had weaker and less consistent effects on PBV,aggression was predominantly influenced by depressive symptoms and sleep disturbances.The analysis also identified key symptoms,such as a“sad mood”and sleep disturbances,as crucial targets for intervention to mitigate the cycle of PBV,depression,anxiety,and aggression.CONCLUSION This study provides important insights for bullying victimization prevention and intervention strategies:(1)Early identification and intervention targeting depression,particularly a“sad mood,”and sleep disturbances;(2)The importance of addressing cyberbullying as a distinct factor influencing mental health;and(3)The need for comprehensive,longitudinal approaches to understanding and intervening in the interconnected mental health issues among adolescents. 展开更多
关键词 Peer bullying victimization DEPRESSION ANXIETY AGGRESSION Adolescents longitudinal study
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The Jamaica Handheld Ultrasound Project:a novel longitudinal point-of-care ultrasound curriculum in a resource-limited setting
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作者 Maxime Montour Pranali Sheth +16 位作者 Steve Foo Simone French Tawanda Jones Giselle Watt Brian Kohen Aamir Bandagi Ariella Gartenberg Michael Halperin Trudy-Ann Johnson-Hylton Jason Ifill Alyssia McEwan Jonathan Maik Michelle Montenegro Rie Seu Nicole Leonard-shiu Hugh Wong Trevor Dixon 《World Journal of Emergency Medicine》 2025年第3期262-265,共4页
Point-of-care ultrasound(POCUS) is recognized as a valuable diagnostic tool,especially in resourcelimited settings(RLS).POCUS provides rapid diagnostic information that enables health professionals to make critical de... Point-of-care ultrasound(POCUS) is recognized as a valuable diagnostic tool,especially in resourcelimited settings(RLS).POCUS provides rapid diagnostic information that enables health professionals to make critical decisions at the bedside.^([1]) Despite the welldocumented benefits of POCUS,access to longitudinal,comprehensive training programs and a lack of trainee feedback are barriers to the widespread use of this technology in such settings.^([2]) 展开更多
关键词 health professionals point care ultrasound curriculum technology training feedback Jamaica handheld ultrasound resource limited settings longitudinal
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Risk-Based Evaluation of Longitudinal Ventilation with Enhanced Safety Concept
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作者 Göran Nygren 《Journal of Civil Engineering and Architecture》 2025年第9期433-443,共11页
The longitudinal ventilation strategy is commonly used for road tunnels in urban environment in Sweden.This is partly due to how tunnels in urban environment was planned and designed before the EU Directive[1](2004/54... The longitudinal ventilation strategy is commonly used for road tunnels in urban environment in Sweden.This is partly due to how tunnels in urban environment was planned and designed before the EU Directive[1](2004/54/EC)came in place.Even in new tunnels both to practical and economic reasons the use of longitudinal ventilation has been an outspoken demand from the Swedish road authority,SRA.Swedish law[2]requires that a risk analysis is carried out to demonstrate that an acceptable level of risk is achieved in the tunnels with longitudinal ventilation if there is a risk of queues.Otherwise transverse or semi-transverse ventilation strategy shall be used.During recent development,or a late awakening,it is clear that dense populated areas in Sweden will experience queues.This threatens the foundation of the Swedish modern tunnel safety concept which calls for enhancement.This paper presents the risk-reducing effect of three alternative strategies,enhancements package,focusing on evacuation safety for road users.It is a combination of traffic management,fixed firefighting systems,reduced distance between escape routes and regulation of traffic with dangerous goods.In addition,it provides a comprehensive review of safety system details,combined with a longitudinal ventilation concept. 展开更多
关键词 longitudinal ventilation QUEUE risk assessment risk mitigation measures safety concept
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Adjustment of thalweg longitudinal profiles in response to sediment silting in cascade reservoirs:A case study of the lower Jinsha River
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作者 WANG Suiji 《Journal of Geographical Sciences》 2025年第7期1497-1515,共19页
How the strong segmentation of cascade reservoir dams and the spatiotemporal changes of sediment retention volume affect the river morphology adjustment in the reservoir area is a scientific issue worthy of exploratio... How the strong segmentation of cascade reservoir dams and the spatiotemporal changes of sediment retention volume affect the river morphology adjustment in the reservoir area is a scientific issue worthy of exploration.This study aims to reveal the adjustment mechanism of the thalweg longitudinal profile of cascade reservoirs.This study focuses on the Xiangjiaba and Xiluodu reservoirs located in the lower reaches of the Jinsha River.Utilizing multi-period observational data of thalweg elevation in reservoir reaches both before and after dam construction,the research employs statistical,geomorphological,and sedimentological methodologies to analyze variation characteristics in the measured curves,trend curves,and theoretical fitting curves of the thalweg longitudinal profile.The investigation ultimately reveals two distinct adjustment patterns in the longitudinal profiles of these cascade reservoirs:the concave curve type and the convex curve type.The former is characterized by weak riverbed scouring and silting changed to rapid aggradation in the upstream section of the reservoir area after dam closure,then changed to slow aggradation in the whole reservoir area,which is the common feature of reservoirs that were built earlier and are relatively located in the downstream(such as the Xiangjiaba Reservoir).The latter is characterized by a straight line or concave curve type with weak riverbed scouring and silting before the dam closure changed to a convex curve type with strong siltation after dam closure,which is the characteristic of reservoirs that were built later and are relatively located in the upstream(such as the Xiluodu Reservoir).The adjustment of the cascade reservoir longitudinal profile is controlled by the spatiotemporal changes of the sediment deposition volume and sedimentation rate in the reservoir area,and the alternating changes of the hydrodynamic gradient and regulation mode affect the spatial heterogeneity of the sedimentation rate.The research results are helpful for understanding the adjustment mechanism of the cascade reservoir longitudinal profile in similar areas and have a guiding role in predicting the adjustment trend of the cascade reservoir longitudinal profile without observation data. 展开更多
关键词 cascade reservoirs longitudinal profile adjustment pattern sediment silting lower Jinsha River
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Innovative methodology for longitudinal crack detection in prestressed concrete sleepers through modal identification and updating
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作者 Morteza Esmaeili Mohammad Seyedkazemi Babak Shiri 《Railway Engineering Science》 2025年第4期766-790,共25页
The operational and regional conditions to which the prestressed concrete sleeper(PCS)is subjected in a railway track significantly contribute to its performance and durability.Maintaining the health of PCS poses chal... The operational and regional conditions to which the prestressed concrete sleeper(PCS)is subjected in a railway track significantly contribute to its performance and durability.Maintaining the health of PCS poses challenges,and one of these issues involves the potential occurrence of longitudinal cracks in reinforcing bars,which can be caused by various constructional,functional,and environmental factors.Longitudinal cracks in PCS compromise the structural performance,resulting in a reduced capacity to withstand the loads exerted by moving vehicles.The current evaluations not only fail to yield a precise parameter for estimating the behavior and response of the PCS,but they also overlook the specific conditions of the PCS,such as prestressing,and only provide limited information regarding existing damage.Balancing the need for accurate evaluation with consideration of costs and resources,and making informed decisions about maintenance and track performance enhancement,has become a multifaceted challenge in ensuring a robust PCS assessment.This research introduces a novel methodology to improve the evaluation of mechanical and geometrical parameters of PCS over their operational lifespan.The objective is to enhance the accuracy of PCS performance estimation by concentrating on detecting longitudinal cracks.The suggested approach seamlessly integrates model updating methods and the finite element(FE)approach to achieve an accurate and timely assessment of PCS conditions.This comprehensive examination scrutinizes the methodology by applying artificial cracks to the PCS.In addition to introducing this assessment approach,a detailed examination is conducted on a laboratory-simulated PCS featuring various combinations of longitudinal cracks measuring 40,80,and 120 cm in length.This systematic and rigorous approach ensures the reliability and robustness of the methodology.Ultimately,the parameters of cross-sectional area,moment of inertia,and modulus of elasticity,which significantly impact the performance of this sleeper,are explored and demonstrated through functional methodologies.The findings suggest that assessing and addressing damage should be conducted through a comprehensive and integrated procedure,taking into account the actual conditions of the PCS.Longitudinal cracks lead to a substantial decrease in the performance of these components in railway tracks.By applying the proposed methods,it is anticipated that the evaluation error for these components will be reduced by approximately 30%compared to visual inspections,particularly in predicting the extent of damage for cracks measuring up to 120 cm.This research has the potential to significantly enhance the evaluation of PCS performance and mitigate the impact of longitudinal cracks on the safety and longevity of ballasted railway tracks in desert areas. 展开更多
关键词 Prestressed concrete sleeper Steel-bar corrosion longitudinal crack detection Modal identification Model updating Ballasted railway track
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Distribution Patterns of Deep Shale Reservoirs and Longitudinal Utilization Degree of Horizontal Wells
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作者 Hai Li Ziqiang Xia +5 位作者 Majia Zheng Weiyang Xie Jianlin Li Ruiqi Gao Gaoxiang Wang Jiangrong Feng 《Energy Engineering》 2025年第12期5039-5054,共16页
To explore and evaluate the longitudinal utilization degree of marine shale gas horizontal wells in southern Sichuan Basin(hereinafter referred to as“southern Sichuan”),focusing on the shale of Wufeng formation-Long... To explore and evaluate the longitudinal utilization degree of marine shale gas horizontal wells in southern Sichuan Basin(hereinafter referred to as“southern Sichuan”),focusing on the shale of Wufeng formation-Longyi1 sub-member in the deep Z block.By using the data from core experiments,well logging,and fracture height detection,a systematic analysis from the perspectives of reservoir distribution,longitudinal utilization height of hydraulic fractures,and longitudinal utilization degree of horizontal wells was conducted.The research results show that:(1)The overall reservoir conditions of theWufeng formation-Longyi1 sub-member in the study area are relatively favorable,although the quality of Type Ⅰ reservoir varies significantly among different well blocks;(2)The proppant tracer fracture height detection results show that fractures tend to extend upwards,the average total fracture height of fracture extend is 12.7 m,with the average upward extension height is 2.5 times the downward extension height;(3)The combination of fracture height and gas well productivity analysis suggests that targeting sub-layer 1 as the horizontal well target can achieve full production of the continuous thickness of Type Ⅰ reservoir in Z2 well block,whereas in Z1 well block,due to the significant proportion of the Wufeng formation in the continuous thickness of Type Ⅰ reservoir,in the areas where the continuous thickness of Type Ⅰ reservoir in Wufeng formation to middle sub-layer 1 is greater than 4 m,horizontal wells cannot achieve full longitudinal utilization of the continuous thickness in top-quality Type Ⅰ reservoir.The conclusion is that due to the limitations of longitudinal utilization height by artificial fracture networks and the variability in the distribution of continuous thickness of Type Ⅰ reservoir,Z1 well block can continue to conduct horizontal well target tests and differentiated fracturing designs to further enhance the longitudinal utilization degree of the top-quality Type Ⅰ reservoir. 展开更多
关键词 Sichuan basin deep shale gas horizontal well longitudinal utilization TypeⅠreservoir
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Commentary on"The association of diet quality and physical activity with cardiovascular disease and mortality in 85,545 alder Australians:A longitudinal study"
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作者 Barbara E.Ainsworth Zeyun Feng 《Journal of Sport and Health Science》 2025年第5期67-69,共3页
There is no way around it.Regular physical activity(PA)and a high-quality diet are essential to promoting good health and prolonging life in middle-aged and older adults.In the November 2024 Issue of the Journal of Sp... There is no way around it.Regular physical activity(PA)and a high-quality diet are essential to promoting good health and prolonging life in middle-aged and older adults.In the November 2024 Issue of the Journal of Sport and Health Science,Ding et al. 展开更多
关键词 cardiovascular disease diet quality MORTALITY middle aged older adults physical activity physical activity pa longitudinal study
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Longitudinal effects of Johnson & Johnson COVID-19 vaccination on metabolic biomarkers in type 2 diabetes mellitus in Ethiopia
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作者 Chala Kenenisa Edae Abdisa Tufa Bedada +2 位作者 Maria Degef Teklemariam Tibebu Girma Solomon Genet Gebre 《World Journal of Diabetes》 2025年第6期201-217,共17页
BACKGROUND The coronavirus disease 2019(COVID-19)pandemic has disproportionately impacted individuals with type 2 diabetes mellitus(T2DM),increasing their risk of severe illness and mortality.Vaccination has been a cr... BACKGROUND The coronavirus disease 2019(COVID-19)pandemic has disproportionately impacted individuals with type 2 diabetes mellitus(T2DM),increasing their risk of severe illness and mortality.Vaccination has been a crucial intervention in mitigating these risks.However,the metabolic effects of COVID-19 vaccination,particularly the Johnson&Johnson(J&J)vaccine,in diabetic populations remain inadequately explored.This study investigated the longitudinal effects of the J&J vaccine on lipid and eicosanoid biomarkers to assess its metabolic safety and potential cardiovascular benefits.AIM To evaluate the long-term impact of the J&J COVID-19 vaccine on lipid and eicosanoid biomarkers in Ethiopian patients with T2DM.METHODS This prospective cohort study was conducted at Adama Hospital Medical College(Oromia,Ethiopia)from May 2023 to June 2024.A total of 224 T2DM patients(57 vaccinated,167 unvaccinated)were monitored for 1 year.Biomarkers including triglycerides(TGs),high-density lipoprotein(HDL),total cholesterol(TC),pro-staglandins(PGs),and thromboxanes(TXs)were measured at baseline and at 3 months,6 months,9 months,and 1 year post-vaccination.Statistical analyses included Generalized Estimating Equations to assess longitudinal biomarker changes.RESULTS TG and PG levels remained stable across all time points.HDL levels showed a temporary decline at 3 months(mean difference[MD]=-4.33;P<0.001)and 6 months(MD=-2.62;P<0.001)but recovered by 9 months(MD=2.09;P=0.001)and 1 year(MD=2.38;P<0.001).TC exhibited a significant decrease at 3 months(MD=-16.44,P=0.001)before stabilizing.TX levels showed a consistent decline across all follow-ups(e.g.,1 year:MD=-0.08;P=0.036),suggesting a reduced thrombotic risk.Correlation analysis indicated significant interrelations among biomarkers,emphasizing their roles in metabolic and inflammatory pathways.CONCLUSION The J&J COVID-19 vaccine exhibited metabolic safety in patients with T2DM,with transient HDL and TC reductions that later stabilized and a sustained TX decline,suggesting potential cardiovascular benefits.Further studies are needed to explore long-term immunometabolic effects on high-risk populations. 展开更多
关键词 Type 2 diabetes mellitus Johnson&Johnson COVID-19 vaccine Metabolic indices Lipid biomarkers Ei-cosanoids longitudinal study
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Transverse incision with longitudinal ligation procedure:Innovation,pitfalls,and clinical perspectives
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作者 Hong-Wei Hua Jiong Wu 《World Journal of Gastroenterology》 2025年第48期194-197,共4页
The transverse incision with longitudinal ligation(TILL)procedure is a new method for treating circumferential prolapsed hemorrhoids.A study by Song et al found TILL to be better than the traditional Milligan-Morgan h... The transverse incision with longitudinal ligation(TILL)procedure is a new method for treating circumferential prolapsed hemorrhoids.A study by Song et al found TILL to be better than the traditional Milligan-Morgan hemorrhoidectomy for short-term results,showing less pain,quicker healing,and lower risk of anal stenosis.TILL reduces tissue tension and controls blood supply,allowing effective removal of diseased tissue while maintaining anal function and structure.However,the study's limitations,including its retrospective,single-center design,small sample size,and short follow-up,restrict the findings'generalizability and ability to assess long-term outcomes like recurrence.Larger,multicenter trials are needed for a thorough evaluation and wider clinical adoption of TILL. 展开更多
关键词 Transverse incision with longitudinal ligation procedure Milligan-Morgan hemorrhoidectomy Circumferential prolapsed hemorrhoids Methodology Proctology Clinical perspectives
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Low and Decreasing Cholesterol Levels and Risk of All-Cause and Cause-Specific Mortality:A Prospective and Longitudinal Cohort Study
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作者 Qin Jiang Jiachen Wu +18 位作者 Yu Yuan Xingjie Hao Pinpin Long Kang Liu Shihe Liu Rong Peng Kuai Yu Rui Zeng Shuohua Chen Handong Yang Xiulou Li Xiaomin Zhang Meian He Lin Wang Xiang Cheng An Pan Shouling Wu Chaolong Wang Tangchun Wu 《Engineering》 2025年第11期251-260,共10页
This prospective study aimed to investigate the associations of untreated cholesterol levels and their longitudinal changes,especially low levels,with all-cause and cause-specific mortality in different populations.Pa... This prospective study aimed to investigate the associations of untreated cholesterol levels and their longitudinal changes,especially low levels,with all-cause and cause-specific mortality in different populations.Participants were drawn from two Chinese cohorts and the UK Biobank,excluding those with lipid-lowering medications,coronary heart disease(CHD),stroke,cancer,clinically diagnosed chronic obstructive pulmonary disease,low body mass index(<18.5 kg·m^(-2))at baseline,and deaths within the first two years to minimize reverse causality.Individual cholesterol changes were assessed in a subset who attended the resurvey after over four years.Mortality data were linked to registries,and risks were estimated using Cox proportional hazards models.A total of 163115 Chinese and 317305 UK adults were included(mean age,49-61 years),with 43%,81%,and 44%males in Dongfeng-Tongji,Kailuan,and UK Biobank cohorts,respectively.During a median follow-up of 9.7-12.9 years,9553 and 15760 deaths were documented in the Chinese cohorts and UK Biobank,respectively.After multivariate adjustments,nonlinear relationships were observed between total cholesterol(TC),low-density lipoprotein cholesterol(LDL-C),and non-high-density lipoprotein cholesterol(non-HDL-C)levels and mortality.In both populations,high cholesterol was primarily associated with CHD mortality,while low cholesterol associated with all-cause and cancer mortality(Pnonlinear≤0.0161).The optimal levels for all-cause mortality risk in Chinese adults(TC:200 mg·dL^(-1);LDL-C:130 mg·dL^(-1);non-HDL-C:155 mg·dL^(-1))were lower than those in the UK Biobank but consistent with guideline recommendation.Additionally,decreasing cholesterol levels over four years were associated with higher all-cause and cancer mortality in the Chinese cohorts(P_(nonlinear)≤0.0100).Participants with low TC,LDL-C,or non-HDL-C levels at both baseline and resurvey experienced elevated all-cause mortality risks in both populations,as did those with low/medium baseline levels and>20%reductions over time in Chinese adults.In conclusion,higher TC,LDL-C,and non-HDL-C levels are associated with elevated CHD mortality.Importantly,low and/or longitudinally decreasing cholesterol levels are robustly associated with increased all-cause and cancer mortality,potentially serving as markers of premature death.Regular cholesterol monitoring,with attention to both high and low levels,is recommended to inform guideline updates and clinical strategies. 展开更多
关键词 Low cholesterol Cancer mortality Cardiovascular disease mortality longitudinal change Prospective cohort study
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Selection and Parameter Optimization of Constraint Systems for Girder-End Longitudinal Displacement Control inThree-Tower Suspension Bridges
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作者 Zihang Wang Ying Peng +3 位作者 Xiong Lan Xiaoyu Bai Chao Deng Yuan Ren 《Structural Durability & Health Monitoring》 2025年第3期643-664,共22页
To investigate the influence of different longitudinal constraint systems on the longitudinal displacement at the girder ends of a three-tower suspension bridge,this study takes the Cangrong Xunjiang Bridge as an engi... To investigate the influence of different longitudinal constraint systems on the longitudinal displacement at the girder ends of a three-tower suspension bridge,this study takes the Cangrong Xunjiang Bridge as an engineering case for finite element analysis.This bridge employs an unprecedented tower-girder constraintmethod,with all vertical supports placed at the transition piers at both ends.This paper aims to study the characteristics of longitudinal displacement control at the girder ends under this novel structure,relying on finite element(FE)analysis.Initially,based on the Weigh In Motion(WIM)data,a random vehicle load model is generated and applied to the finite elementmodel.Several longitudinal constraint systems are proposed,and their effects on the structural response of the bridge are compared.The most reasonable system,balancing girder-end displacement and transitional pier stress,is selected.Subsequently,the study examines the impact of different viscous damper parameters on key structural response indicators,including cumulative longitudinal displacement at the girder ends,maximum longitudinal displacement at the girder ends,cumulative longitudinal displacement at the pier tops,maximum longitudinal displacement at the pier tops,longitudinal acceleration at the pier tops,and maximum bending moment at the pier bottoms.Finally,the coefficient of variation(CV)-TOPSIS method is used to optimize the viscous damper parameters for multiple objectives.The results show that adding viscous dampers at the side towers,in addition to the existing longitudinal limit bearings at the central tower,can most effectively reduce the response of structural indicators.The changes in these indicators are not entirely consistent with variations in damping coefficient and velocity exponent.The damper parameters significantly influence cumulative longitudinal displacement at the girder ends,cumulative longitudinal displacement at the pier tops,and maximum bending moments at the pier bottoms.The optimal damper parameters are found to be a damping coefficient of 5000 kN/(m/s)0.2 and a velocity exponent of 0.2. 展开更多
关键词 Three-tower suspension bridge vehicle loads longitudinal constraint system viscous damper multiobjective parameter optimization
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Longitudinal Associations of Loneliness with Mental and Physical Health in Ageing Adults in South Africa
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作者 Karl Peltzer 《International Journal of Mental Health Promotion》 2025年第5期625-635,共11页
Objectives Few studies have investigated longitudinal associations of loneliness with health outcomes in Africa.This study aimed to assess the longitudinal associations between loneliness and mental and physical healt... Objectives Few studies have investigated longitudinal associations of loneliness with health outcomes in Africa.This study aimed to assess the longitudinal associations between loneliness and mental and physical health among aging adults in South Africa.Methods Data from the 7-year longitudinal Health and Ageing in Africa(HAALSI)study conducted in South Africa were used in the analysis(analytic sample:n=3707,aged 40 years and older).Loneliness was measured with one question.Longitudinal relationships between loneliness and each health outcome were estimated using Generalized Estimating Equations analysis(GEE),hazard ratios(HRs)(95%CI)were used to determine the relationship between loneliness and 7-year mortality in the entire sample,and correlations between incident health outcomes and loneliness were evaluated using logistic regressions.Results The prevalence of loneliness was 12.1%in 2015,16.9%in 2019,and 16.3%in 2022.Multivariable analysis showed that loneliness was positively associated with the prevalence and/or incidence of four poor mental health indicators(e.g.,poor sleep quality,AOR=1.53,95%CI:1.30–1.80),four physical ill-health indicators(e.g.,incident kidney disease,AOR=2.50,95%CI:1.41–4.42),mortality(Hazard Ratio=1.20,95%CI=1.04–1.39),and three poor behavioral health indicators(e.g.,current tobacco use,AOR=1.21,95%CI=1.04–1.42).Conclusion The study discovered that several outcomes related to mental,physical,and behavioral health were associated with loneliness.Enhancing the detection and management of loneliness could lower mental and physical illness in aging adults in South Africa. 展开更多
关键词 LONELINESS mental health longitudinal study South Africa
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Association between long-term total sleep duration and physical activity trajectories and cardiovascular diseases among middle-aged and older adults:a 9-year longitudinal study
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作者 Yan LI Ya-Ling HUANG +2 位作者 Hai-Rou SU Gui-Bing WU Zhi-Xin ZHU 《Journal of Geriatric Cardiology》 2025年第7期625-637,共13页
Background It remains unclear whether sleep duration and physical activity(PA)trajectories in middle-aged and older adults are associated with different risks of cardiovascular diseases(CVDs).This study aimed to explo... Background It remains unclear whether sleep duration and physical activity(PA)trajectories in middle-aged and older adults are associated with different risks of cardiovascular diseases(CVDs).This study aimed to explore the trajectories of total sleep duration and PA among middle-aged and older Chinese adults and their impact on CVD risk.Methods This study was based on the China Health and Retirement Longitudinal Study.12009 adults aged 45 years and older from five waves were included.CVD events were measured by self-reports of heart disease and stroke.We first used groupbased trajectory modeling to identify total sleep duration and PA trajectories from 2011 to 2020,and then employed logistic regression models to analyze their risk for CVD.Results We identified three sleep duration and PA trajectories.The risk of heart disease increased by 33%(OR=1.31,95%CI:1.12-1.53)for the short sleep duration trajectory(vs.moderate sleep duration trajectory),by 40%(OR=1.40,95%CI:1.06-1.84)for the high decreasing PA trajectory,and by 20%(OR=1.20,95%CI:1.01-1.42)for the low stable PA trajectory(vs.high stable PA trajectory),respectively.Similar results for stroke and CVD as the outcomes were also observed,but the higher risk of stroke in the high decreasing PA trajectory group was not statistically significant.The joint effects of sleep and PA showed lower risks of heart disease and stroke in trajectories with moderate or long sleep duration and high stable PA compared with short sleep duration and a low stable PA trajectory.Conclusions Short total sleep duration,high decreasing PA,and low stable PA trajectories could increase the risk of CVDs among middle-aged and older adults.Long-term moderate to long total sleep durations and high stable PA trajectories might be optimal for preventing CVDs. 展开更多
关键词 sleep duration physical activity pa trajectories cardiovascular diseases cvds cardiovascular diseases middle aged older adults events measured physical activity longitudinal study
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Triadic concept analysis for insights extraction from longitudinal studies in health
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作者 Joao Pedro Santos Atilio Ferreira Silva +2 位作者 Henrique Fernandes Viana Mendes Mark Alan Junho Song Luis Enrique Zarate 《Data Science and Management》 2025年第2期160-173,共14页
In the health field,longitudinal studies involve the recording of clinical observations of the same sample of pa-tients over successive periods,referred to as waves.This type of database serves as a valuable source of... In the health field,longitudinal studies involve the recording of clinical observations of the same sample of pa-tients over successive periods,referred to as waves.This type of database serves as a valuable source of infor-mation and insights,particularly when examining the temporal aspect,allowing the extraction of relevant and non-obvious knowledge.The triadic concept analysis theory has been proposed to describe the ternary re-lationships between objects,attributes,and conditions.In this study,we present a methodology for exploring longitudinal health databases using both the triadic theory and triadic rules,which are similar to association rules but incorporate temporal relations.Through four case studies,we demonstrate the potential of applying triadic analysis to longitudinal databases to identify risk patterns,enhance decision-making processes,and deepen our understanding of temporal dynamics.These findings suggest a promising approach for describing longitudinal databases and obtaining insights to improve clinical decision-support systems for disease treatment. 展开更多
关键词 Data mining longitudinal data mining Triadic rules Medical informatics Clinical data processing Triadic concept analysis
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