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The Application of Health Education Based on the Transtheoretical Model on Self-Management and Vascular Crisis in Patients Undergoing Finger Replantation Surgery
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作者 Hongxia Cheng Wenjie Wang 《Journal of Clinical and Nursing Research》 2026年第2期229-235,共7页
Objective:To investigate the effects of health education based on the Transtheoretical Model(TTM)on self-management and vascular crisis in patients undergoing finger replantation surgery.Methods:A total of 106 patient... Objective:To investigate the effects of health education based on the Transtheoretical Model(TTM)on self-management and vascular crisis in patients undergoing finger replantation surgery.Methods:A total of 106 patients who underwent finger replantation surgery between January 2025 and December 2025 were randomly divided into control and intervention groups using a random number table method(control group,n=52;intervention group,n=54).The control group received standard perioperative nursing care,while the intervention group received TTM-based health education in addition to standard care.Self-management levels and incidence of vascular crisis were compared between the two groups.Results:After intervention,the Adult Health Self-Management Skills Rating Scale(AHSMSRS)scores in both groups increased significantly compared with baseline(control:91.26±5.49 to 116.97±8.15;intervention:90.39±6.72 to 136.38±9.36,p<0.001).The intervention group showed significantly higher AHSMSRS scores than the control group(136.38±9.36 vs.116.97±8.15,p<0.001).Similarly,general self-efficacy scores increased significantly in both groups,with the intervention group demonstrating superior improvement(36.73±4.78 vs.28.49±4.11,p<0.001).The incidence of vascular crisis was significantly lower in the intervention group(5.5%)compared with the control group(19.23%,χ2=3.421,p<0.05).Conclusion:Health education based on the Transtheoretical Model effectively enhances self-management abilities and self-efficacy in patients undergoing finger replantation surgery,and significantly reduces the incidence of postoperative vascular crisis. 展开更多
关键词 Transtheoretical model Health education Finger replantation SELF-MANAGEMENT Vascular crisis
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A theoretical model for drawing body in sublevel top coal caving mining and its validations
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作者 Jinwang Zhang Xiaohang Wan +7 位作者 Shengli Yang Melih Geniş AhmetÖzarslan Dongliang Cheng Weijie Wei Haobo Zhang Zhengyang Song Jin Zhao 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第3期1992-2014,共23页
The sublevel top coal caving(SLTCC)mining is widely employed in steeply inclined and thick coal seams.In SLTCC,the large coal drawing height and the influence of roof and floor boundaries introduce significant complex... The sublevel top coal caving(SLTCC)mining is widely employed in steeply inclined and thick coal seams.In SLTCC,the large coal drawing height and the influence of roof and floor boundaries introduce significant complexity into the coal extraction process.The study demonstrates that,in an SLTCC working face,the granular nature of top coal gives rise to a'locking-embedding'effect and a'loosening-compaction'cycle during the drawing process.These phenomena invalidate several core assumptions of the conventional Bergmark-Roos(B-R)model,which is no longer fully established,and the maximum moving angle changes dynamically.Therefore,an improved B-R model was proposed to account for the dynamic variations in particle shape and maximum transport angle,and the corresponding boundary equations of the drawing body were derived.Additionally,a novel numerical simulation method based on the rolling resistance linear model(RRLM),which takes into account particle shape,has been introduced.Validation was conducted through numerical simulations and physical experiments.Both numerical and physical tests confirmed that the improved B-R model more accurately captures the drawing body shape in SLTCC.Field measurement data in Wudong coal mine in Xinjiang,China,further substantiated the model's validity.In addition,as sublevel height increases,the drawing body exhibits markedly different evolution trends on the roof-and floor-side boundaries.Formulas for the improved B-R model at various sublevel heights were established.The research may provide new approaches for SLTCC simulations and theoretical calculations of drawing body shape at different sublevel heights. 展开更多
关键词 Sublevel top coal caving(SLTCC)mining Drawing body of top coal Rolling resistance model Bergmark-Roos(B-R)model
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A refined nonlinear theoretical model for mechanical analysis of tunnels subjected to strike-slip faulting with multiple fault planes
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作者 Henghong Yang Mingnian Wang +1 位作者 Li Yu Xiao Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第8期5018-5037,共20页
During strike-slip fault dislocation,multiple fault planes are commonly observed.The resulting permanent ground deformation can lead to profound structural damage to tunnels.However,existing analytical models do not c... During strike-slip fault dislocation,multiple fault planes are commonly observed.The resulting permanent ground deformation can lead to profound structural damage to tunnels.However,existing analytical models do not consider multiple fault planes.Instead,they concentrate the entire fault displacement onto a single fault plane for analysis,thereby giving rise to notable errors in the calculated results.To address this issue,a refined nonlinear theoretical model was established to analyze the mechanical responses of the tunnels subjected to multiple strike-slip fault dislocations.The analytical model considers the number of fault planes,nonlinear soil‒tunnel interactions,geometric nonlinearity,and fault zone width,leading to a significant improvement in its range of applicability and calculation accuracy.The results of the analytical model are in agreement,both qualitatively and quantitatively,with the model test and numerical results.Then,based on the proposed theoretical model,a sensitivity analysis of parameters was conducted,focusing on the variables such as the number of fault planes,fault plane distance(d),fault displacement ratio(η),burial depth(C),crossing angle(β),tunnel diameter(D),fault zone width(Wf),and strike-slip fault displacement(Δfs).The results show that the peak shear force(Vmax),bending moment(Mmax),and axial force(Nmax)decrease with increasing d.The Vmax of the tunnel is found at the fault plane with the largest fault displacement.C,D,andΔfs contribute to the increases in Vmax,Mmax,and Nmax.Additionally,increasing the number of fault planes reduces Vmax and Mmax,whereas the variation in Nmax remains minimal. 展开更多
关键词 Strike-slip fault Tunnel engineering theoretical model Multiply fault plane Nonlinear soil‒tunnel interaction Finite element method
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Effect of geometry ratios on droplet breakup in a T-junction microchannel:A theoretical predictive model
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作者 Thanh Tung Nguyen Van Thanh Hoang 《Chinese Journal of Chemical Engineering》 2025年第12期13-20,共8页
Understanding and predicting droplet breakup is essential in droplet-based microfluidic systems,as it enables precise control over droplet manipulation for various applications.In this study,droplet breakup behavior i... Understanding and predicting droplet breakup is essential in droplet-based microfluidic systems,as it enables precise control over droplet manipulation for various applications.In this study,droplet breakup behavior in a T-junction microchannel is investigated under the influence of microchannel geometry using three-dimensional numerical simulations.A theoretical model is developed based on the balance between surface tension and viscous drag forces acting on the droplet,incorporating the effects of geometric parameters on droplet length.This model predicts the critical Capillary number required for breakup to occur.The theoretical predictions are validated using both previous research data and the present numerical simulations.The results show that the model accurately predicts the transition between breakup and non-breakup regimes.Specifically,an increase in sidearm length ratio inhibits droplet breakup and leads to an asymmetric breakup regime.Furthermore,increasing the outlet-to-inlet width ratio also reduces the likelihood of droplet breakup.These findings provide a predictive framework for understanding and controlling droplet dynamics in microfluidic T-junctions,with potential applications in lab-on-a-chip technologies. 展开更多
关键词 T-JUNCTION Sidearm length Capillary number BREAKUP Width ratio theoretical predictive model
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Rational theoretical modeling for reconstructed transition metal sulfides:Insights into oxygen evolution reaction catalysts
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作者 Wanying Wang Yuang Shi +6 位作者 Jinchao Xu Huan Li Qingyu Shan Chunning Zhao Bin Shao Ruiting Hao Weichao Wang 《Journal of Energy Chemistry》 2025年第8期768-779,共12页
Reconstruction during the oxygen evolution reaction(OER)significantly transforms the geometric structure of transition metal compounds,leading to enhanced catalytic performance.However,the resulting structural disorde... Reconstruction during the oxygen evolution reaction(OER)significantly transforms the geometric structure of transition metal compounds,leading to enhanced catalytic performance.However,the resulting structural disorder complicates the development of accurate theoretical models.In this study,CoS2 is used as a model system to establish a framework for rationally modeling reconstructed OER catalysts based on density functional theory(DFT).In the reconstruction process,sulfur atoms are likely to be substituted by oxygen atoms,leading to the formation of the CoOOH phase.Based on the difference in reconstruction degree,we constructed three types of models:doping,heterostructure,and fully reconstructed,representing the reconstruction degree from minimal to full phase transition,respectively.Fully reconstructed models,which account for strain and vacancy effects,effectively simulate the unique coordination environments of reconstructed catalysts.Model e-CoOOH achieves a theoretical overpotential of 0.38 V,outperforming pristine CoOOH(0.56 V),demonstrating that the unique structural features resulting from reconstruction improve OER performance.The doping model and the heterostructure model are helpful to explain the electronic structure and performance transformation of the reconstruction process.This work provides a rational theoretical modeling approach,which is conducive to improving the reliability of the theoretical OER performance of the reconstructed catalyst. 展开更多
关键词 Transition metal compounds Oxygen evolution reaction(OER) Catalyst reconstruction theoretical model
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Theoretical Studies on Stability of Oxygen-Evolving Center Model Complex Mn_(4)CaO_(4)in Oxidative Condition
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作者 Zheng Sun Hongjun Fan 《Chinese Journal of Chemical Physics》 2025年第6期893-906,I0025-I0174,I0239,共165页
The photosynthetic oxygen-evolving center(OEC)is a unique Mn_(4)CaO_(5)cluster catalyzing the water oxidation into electrons,protons and O_(2)through a five-intermediate state cycle(Sn,n=0,1,2,3,4).The modeling of OEC... The photosynthetic oxygen-evolving center(OEC)is a unique Mn_(4)CaO_(5)cluster catalyzing the water oxidation into electrons,protons and O_(2)through a five-intermediate state cycle(Sn,n=0,1,2,3,4).The modeling of OEC is essential for understanding the water oxidation mechanism and developing high efficient water oxidation catalysts.Recently,a series of Mn_(4)CaO_(4)model complexes have been synthesized,which have very similar structures to OEC and also show reactivity of water oxidation.In this work,we employed DFT method to investigate the stability of Mn_(4)CaO_(4)model complex in oxidative conditions,aiming to figure out whether it decomposes itself to release O_(2)during the catalytic water oxidation process.We discovered that the barrier for the O−O bond formation is quite high in the S1 and S2 states,while decreases to 40.2 kcal/mol in the S3 state,indicating the good stability in all oxidation states under normal conditions.Acetonitrile and pyridine can effectively reduce the barrier to 36.5 kcal/mol and 29.9 kcal/mol,respectively.Therefore,strong Lewis base,such as pyridine,could be harmful to the stability of Mn_(4)CaO_(4)and shall be avoided when designing such a catalytic system.Once the O−O bond is formed,Mn_(4)CaO_(4)in the S3 state can readily decompose to O_(2),solvated Ca^(2+)and Mn_(4)O_(2)complex,with the assistance of acetonitrile or pyridine.As a comparison,the O_(2)decomposition in the S2 state is kinetically hindered and thermodynamically disfavored.The S4 state Mn_(4)CaO_(4)has a much lower barrier for O-O bond formation,and is unstable.However,the S4 state Mn_(4)CaO_(4)is difficult to achieve under water oxidation condition,as evidenced by the calculated redox potential of 2.3 V for S3→S4 transition. 展开更多
关键词 Photosynthetic oxygen-evolving center Artificial modeling theoretical study O−O bond STABILITY
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Dynamic response of RC columns under off-central explosions:Experimental,theoretical studies and neural network prediction
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作者 Hao Wang Xiangyu Li +2 位作者 Yong Peng Zhandong Tian Fangyun Lu 《Defence Technology(防务技术)》 2026年第2期314-336,共23页
Reinforced concrete(RC)columns are often subjected to off-central explosion due to the uncertainty of blast locations.However,few studies have focused on the dynamic response of RC columns under offcentral explosions.... Reinforced concrete(RC)columns are often subjected to off-central explosion due to the uncertainty of blast locations.However,few studies have focused on the dynamic response of RC columns under offcentral explosions.A field blast experiment was conducted under close-in explosion with varying detonation offset distances(0 m,0.5 m,and 1 m),the overpressure load and dynamic responses of the full-scale RC columns were measured.Compared with the centrally detonated condition,a relative offset distance of 1.67 decreases the maximum and residual deflections of the RC column by 16.8%and 21.4%,respectively,while increasing the maximum and residual support rotations by 24.7%and 17.8%.Based on the experimental results,a theoretical model was proposed that considers the detonation location and charge mass,boundary conditions,axial compression ratio and material properties.The theoretical model exhibited good agreement with the experimental results,with prediction errors below 10%for both maximum and residual deflection.The effects of parameters were analyzed,and it indicated that an increase in offset distance results in decreased maximum and residual deflections but an increased support angle,thereby exacerbating damage.Higher axial load ratio,span-depth ratio,and longitudinal reinforcement ratio reduce both deflections and support angle.Additionally,a rapid method to predict the maximum and residual deflection of RC columns under off-central blast loading was also proposed based on the Generalized Regression Neural Network(GRNN).Eleven features which related to the RC column properties and the blast characteristics were used in the training process of GRNN,and accurate predictions were achieved with prediction errors within 20%.This study fills the gap in predicting the dynamic response of RC columns under off-central explosion,providing valuable references for blast-resistant design. 展开更多
关键词 Dynamic responses RC columns Off-central explosions theoretical model GRNN
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Prediction of permeability of sands treated by enzyme-induced calcium precipitation(EICP):Mathematical model
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作者 Qi-Wu Jiang Ming Huang +4 位作者 Ming-Juan Cui Xiao-Ping Zhang Gui-Xiao Jin Shuai-Xing Yan Wen-Chieh Cheng 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第3期2339-2351,共13页
Enzyme-induced carbonate precipitation(EICP)is a potential ground improvement method that can reduce the permeability of sands.However,the traditional mathematical models are hard to accurately predict the permeabilit... Enzyme-induced carbonate precipitation(EICP)is a potential ground improvement method that can reduce the permeability of sands.However,the traditional mathematical models are hard to accurately predict the permeability of EICP-treated sands.In this study,the mathematical model was established for predicting the permeability of EICP-treated sands based on Kozeny-Carman equation.The effects of calcium carbonate precipitation on the porosity,tortuosity,and specific surface area of the EICP-treated sands were considered in the model.To validate the model,the bio-cemented sand column tests with different grain size distributions(coarse,medium,and fine sands)and treatment numbers(6,8,and 10 times)were conducted.The calcium carbonate content(CCC)and permeability of EICP-treated sands were measured.The validation of the model was confirmed through a comparative analysis of theoretical and experimental results.Furthermore,the impacts of porosity,particle size,CCC,and specific surface area on the hydraulic conductivity of EICP-treated sands were analyzed.The results showed that the model can reflect the hydraulic conductivity of EICP-treated sands under different particle size distributions and degrees of cementation,demonstrating broad applicability.Parametric analysis indicated the hydraulic conductivity gradually decreases with increasing CCC and specific surface area.Conversely,the hydraulic conductivity gradually increases with increasing porosity(n)and particle size(d50),with porosity exhibiting a significantly higher sensitivity than particle size.In summary,this study contributes theoretical foundations for the practical implementation of EICP technology in reducing soil permeability. 展开更多
关键词 Enzyme-induced carbonate precipitation(EICP) theoretical model Kozeny-Carman equation Calcium carbonate precipitation PERMEABILITY
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Vibrations induced by time-delayed double blastholes in underground rocks:Experimental study and theoretical analysis
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作者 Yonggang Gou Gui Yang +2 位作者 Xianyang Qiu Kun Ji Yumin Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1108-1125,共18页
Time-delayed blasting is widely utilized in engineering to mitigate induced vibration hazards and enhance fragmentation.The underlying vibration reduction principle is the decrease of the charge weight per delay,while... Time-delayed blasting is widely utilized in engineering to mitigate induced vibration hazards and enhance fragmentation.The underlying vibration reduction principle is the decrease of the charge weight per delay,while the potential for further vibration reduction remains debated,largely due to unclear underlying mechanisms.In light of the popularization of electronic detonators and the representativeness of double-hole configurationsfor multiple blastholes,it is essential to investigate the vibration characteristics induced by time-delayed double blastholes.Therefore,a series of doubleborehole experimental blasts was conducted in an underground roadway to clarify the variation in vibration from single-hole to dual-hole conditions.Based on the experimental data and inherent limitations,an exact full-fieldtheoretical model was further employed to systematically analyze the effects of delay time,charge length,and borehole inclination angle on vibrations induced by various doublehole configurations.The experimental data and theoretical analysis reveal that the general scaled distance effectively predicts vibrations in delayed blasting but does not reflectvibration reduction.Increasing delay time causes fluctuatingPPVs,which stabilize slightly above single-hole PPVs as delay times exceed a certain value.The delayed blasting primarily reduces near-fieldfrequencies.Longer charge lengths in double boreholes increase PPV levels and attenuation rates within a certain length,and the vibration behavior of combined long and short charge lengths is governed by the long blasthole.Larger blasthole inclination angles enhance vibration amplitude and reduce PPV attenuation rates.Optimizing inclination angles is more critical than adjusting delay times,and parallel boreholes offer the best vibration control. 展开更多
关键词 Vibration of double blastholes Experimental data theoretical model Delay time Wave superposition
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A literature review and outlook of advertising avoidance:An integrated theoretical framework based on the SOMR model
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作者 Shengliang Zhang Jianhui Jin Xiaodong Li 《中国科学技术大学学报》 北大核心 2025年第1期2-16,1,I0001,共17页
Advertising avoidance is resistance to advertising intrusion.This issue has been the subject of much academic research in recent years.To guide scholars to better carry out relevant research and promote enterprises to... Advertising avoidance is resistance to advertising intrusion.This issue has been the subject of much academic research in recent years.To guide scholars to better carry out relevant research and promote enterprises to better implement advertising activities,this study intends to summarize the relevant research on advertising avoidance in recent years.The specific method is to use the core literature meta-analysis method to identify,filter,and screen relevant literature published in core journals from 1997 to 2020 with the keywords advertising avoidance and advertising resistance.We review the collected articles from the following perspectives:the definition and classification,external stimulating factors,internal perception factors,and moderating factors of advertising avoidance.On this basis,the SOMR model of advertising avoidance is constructed according to the SOR model.Finally,some prospects for future related research are presented. 展开更多
关键词 ADVERTISING advertising avoidance SOMR model perceived value perceived infringement
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A decision framework for rural domestic sewage treatment models and process:Evidence from Inner Mongolia Autonomous Region,China 被引量:1
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作者 Ying Yan Pengyu Li +5 位作者 Zixuan Wang Yubo Tan Tianlong Zheng Jianguo Liu Xiaoxia Yang Junxin Liu 《Journal of Environmental Sciences》 2026年第1期302-311,共10页
Rural domestic sewage treatment is critical for environmental protection.This study defines the spatial pattern of villages from the perspective of rural sewage treatment and develops an integrated decision-making sys... Rural domestic sewage treatment is critical for environmental protection.This study defines the spatial pattern of villages from the perspective of rural sewage treatment and develops an integrated decision-making system to propose a sewage treatment mode and scheme suitable for local conditions.By considering the village spatial layout and terrain factors,a decision tree model of residential density and terrain type was constructed with accuracies of 76.47%and 96.00%,respectively.Combined with binary classification probability unit regression,an appropriate sewage treatment mode for the village was determined with 87.00%accuracy.The Analytic Hierarchy Process(AHP),combined with the Technique for Order Preference(TOPSIS)by Similarity to an Ideal Solution model,formed the basis for optimal treatment process selection under different emission standards.Verification was conducted in 542 villages across three counties of the Inner Mongolia Autonomous Region,focusing on the standard effluent effect(0.3773),low investment cost(0.3196),and high standard effluent effect(0.5115)to determine the best treatment process for the same emission standard under different needs.The annual environmental and carbon emission benefits of sewage treatment in these villages were estimated.This model matches village density,geographic feature,and social development level,and provides scientific support and a theoretical basis for rural sewage treatment decision-making. 展开更多
关键词 Rural domestic sewage Sewage treatment model DECISION-MAKING Environmental-economic benefits Inner Mongolia
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Conjugate Usage of Experimental for and Theoretical Models Aqua Carboxymethyl Cellulose Nanofluid Flow in Convergent-Divergent Shaped Microchannel
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作者 Shervin Fateh Khanshir Saeed Dinarvand Ramtin Fateh Khanshir 《Frontiers in Heat and Mass Transfer》 2025年第2期663-684,共22页
This article aims tomodel and analyze the heat and fluid flow characteristics of a carboxymethyl cellulose(CMC)nanofluid within a convergent-divergent shaped microchannel(Two-dimensional).The base fluid,water+CMC(0.5%... This article aims tomodel and analyze the heat and fluid flow characteristics of a carboxymethyl cellulose(CMC)nanofluid within a convergent-divergent shaped microchannel(Two-dimensional).The base fluid,water+CMC(0.5%),is mixed with CuO and Al2O3 nanoparticles at volume fractions of 0.5%and 1.5%,respectively.The research is conducted through the conjugate usage of experimental and theoretical models to represent more realistic properties of the non-Newtonian nanofluid.Three types of microchannels including straight,divergent,and convergent are considered,all having the same length and identical inlet cross-sectional area.Using ANSYS FLUENT software,Navier-Stokes equations are solved for the laminar flow of the non-Newtonian nanofluid.The study examines the effects of Reynolds number,nanoparticle concentration and type,and microchannel geometry on flow and heat transfer.The results prove that the alumina nanoparticles outperform copper oxide in increasing the Nusselt number at a 0.5% volume fraction,while copper oxide nanoparticles excel at a 1.5%volume fraction.Moreover,in the selected case study,as the Reynolds number increases from 100 to 500,the Nusselt number rises by 56.26% in straight geometry,52.93% in divergent geometry,and 59.10%in convergent geometry.Besides,the Nusselt number enhances by 18.75% when transitioning from straight to convergent geometry at a Reynolds number of 500,and by 19.81%at a Reynolds number of 1000.Finally,the results of the research depict that the use of thermophysical properties derived from the experimental achievements,despite creating complexity in the modeling and the solution method,leads to more accurate and realistic outputs. 展开更多
关键词 Convergent-divergent microchannel CMC-base nanofluid non-Newtonian numerical simulation experimental model
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Transtheoretical Model-based Motivational Interviewing Improves Psychological Resilience and Self-management in Patients Undergoing Finger Replantation
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作者 Wenjie WANG Na WANG Dongyun ZHANG 《Medicinal Plant》 2025年第5期67-69,共3页
[Objectives]To explore the effects of motivational interviewing intervention based on the transtheoretical model(TTM)on psychological resilience and self-management in patients undergoing finger reimplantation after a... [Objectives]To explore the effects of motivational interviewing intervention based on the transtheoretical model(TTM)on psychological resilience and self-management in patients undergoing finger reimplantation after amputation.[Methods]The patients with finger replantation due to fractures admitted from October 2024 to June 2025 were divided into either the control group or the observation group according to the random number table method,with 40 cases in each group.The control group received conventional perioperative care,while the observation group underwent motivational interviewing based on TTM framework on the basis of the control group.The psychological resilience and self-management levels of the two patient groups were then compared following their respective care interventions.[Results]The psychological resilience and self-management scores of the patients were significantly higher than those of the control group after the intervention,with the difference being statistically significant(P<0.05).[Conclusions]Motivational interviewing based on the TTM can effectively improve the psychological resilience and self-management in patients undergoing severed finger reimplantation,while effectively reducing the occurrence of vascular crisis. 展开更多
关键词 Finger replantation Psychological resilience SELF-MANAGEMENT Transtheoretical model(TTM) Motivational interviewing
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Description and Evaluation of the Emission and Atmospheric Processes Integrated and Coupled Community(EPICC)Model Version 1.0 被引量:1
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作者 EPICC Model Working Group 《Advances in Atmospheric Sciences》 2026年第4期671-694,I0001-I0006,共30页
We present a comprehensive description and benchmark evaluation of the global–regional chemical transport model called the Emission and Atmospheric Processes Integrated and Coupled Community(EPICC)model.The framework... We present a comprehensive description and benchmark evaluation of the global–regional chemical transport model called the Emission and Atmospheric Processes Integrated and Coupled Community(EPICC)model.The framework incorporates(1)grid configuration,(2)transport dynamics,(3)chemical mechanisms,(4)aerosol processes,(5)wet/dry deposition parameterizations,and(6)heterogeneous chemistry treatments associated with sulfate,nitrous acid(HONO)chemistry,and aerosol/cloud–photolysis interactions(APIs/CPIs).Openly shared with the atmospheric research community,the model facilitates integration of advanced physicochemical schemes to enhance simulation accuracy.Globally,the model demonstrates realistic representations of ozone(O_(3))and aerosol optical depth.The EPICC model generally demonstrates robust performance in simulating regional concentrations of O_(3) and PM_(2.5)(and its components)in China.It successfully captures vertical profiles of both global and regional O_(3).Notably,the model mitigates frequently reported sulfate underestimations in highly industrialized regions of China.The model accurately captures two regional severe pollution episodes observed in eastern China(January/June 2021).Sensitivity experiments highlight the critical roles of heterogeneous chemical mechanisms associated with sulfate,HONO chemistry,APIs,and CPIs in capturing PM_(2.5) and O_(3) concentrations in China.Improved sulfate mechanisms result in an increase of approximately 32.4%(2.8μg m^(−3))in simulated winter sulfate concentrations when observations exceed 10μg m^(−3).Enhanced HONO elevates winter O_(3) and PM_(2.5) by≤20 and≤10μg m^(−3),respectively.Overall,CPIs dominate over APIs in improving O_(3) and PM_(2.5) simulations across China.Locally,APIs mitigate PM_(2.5) and O_(3) discrepancies in the Sichuan Basin.Seasonal cloud–chemistry coupling explains the weaker impact of PM_(2.5) in summer. 展开更多
关键词 EPICC model PM_(2.5) O_(3) sulfate nitrous acid aerosol/cloud-photolysis interactions
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Examining theoretical applicability of displacement discontinuity model to wave propagation across rock discontinuities
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作者 Yan Zhang Jianbo Zhu +2 位作者 Haohao Xu Dongya Han Weiyue Bao 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2146-2158,共13页
Rock discontinuities such as joints widely exist in natural rock masses,and wave attenuation through rock masses is mainly caused by discontinuities.The displacement discontinuity model(DDM)has been widely used in the... Rock discontinuities such as joints widely exist in natural rock masses,and wave attenuation through rock masses is mainly caused by discontinuities.The displacement discontinuity model(DDM)has been widely used in theoretical and numerical analysis of wave propagation across rock discontinuity.However,the circumstance under which the DDM is applicable to predict wave propagation across rock discontinuity remains poorly understood.In this study,theoretical analysis and ultrasonic laboratory tests were carried out to examine the theoretical applicability of the DDM for wave propagation,where specimens with rough joints comprising regular rectangular asperities of different spacings and heights were prepared by 3D printing technology.It is found that the theoretical applicability of the DDM to predict wave propagation across rock discontinuity is determined by three joint parameters,i.e.the dimensionless asperity spacing(L),the dimensionless asperity height(H)and the groove density(D).Through theoretical analysis and laboratory tests,the conditions under which the DDM is applicable are derived as follows:and,.With increase in the groove density,the thresholds of the dimensionless asperity spacing and the dimensionless asperity height show a decreasing trend.In addition,the transmission coefficient in the frequency domain decreases with increasing groove density,dimensionless asperity spacing or dimensionless asperity height.The findings can facilitate our understanding of DDM for predicting wave propagation across rock discontinuity. 展开更多
关键词 Displacement discontinuity model Wave propagation 3D printing Joint stiffness Joint roughness
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Agri-Eval:Multi-level Large Language Model Valuation Benchmark for Agriculture
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作者 WANG Yaojun GE Mingliang +2 位作者 XU Guowei ZHANG Qiyu BIE Yuhui 《农业机械学报》 北大核心 2026年第1期290-299,共10页
Model evaluation using benchmark datasets is an important method to measure the capability of large language models(LLMs)in specific domains,and it is mainly used to assess the knowledge and reasoning abilities of LLM... Model evaluation using benchmark datasets is an important method to measure the capability of large language models(LLMs)in specific domains,and it is mainly used to assess the knowledge and reasoning abilities of LLMs.Therefore,in order to better assess the capability of LLMs in the agricultural domain,Agri-Eval was proposed as a benchmark for assessing the knowledge and reasoning ability of LLMs in agriculture.The assessment dataset used in Agri-Eval covered seven major disciplines in the agricultural domain:crop science,horticulture,plant protection,animal husbandry,forest science,aquaculture science,and grass science,and contained a total of 2283 questions.Among domestic general-purpose LLMs,DeepSeek R1 performed best with an accuracy rate of 75.49%.In the realm of international general-purpose LLMs,Gemini 2.0 pro exp 0205 standed out as the top performer,achieving an accuracy rate of 74.28%.As an LLMs in agriculture vertical,Shennong V2.0 outperformed all the LLMs in China,and the answer accuracy rate of agricultural knowledge exceeded that of all the existing general-purpose LLMs.The launch of Agri-Eval helped the LLM developers to comprehensively evaluate the model's capability in the field of agriculture through a variety of tasks and tests to promote the development of the LLMs in the field of agriculture. 展开更多
关键词 large language models assessment systems agricultural knowledge agricultural datasets
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Ecological Dynamics of a Logistic Population Model with Impulsive Age-selective Harvesting
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作者 DAI Xiangjun JIAO Jianjun 《应用数学》 北大核心 2026年第1期72-79,共8页
In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asy... In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asymptotic stability of the trivial solution and the positive periodic solution.Finally,numerical simulations are presented to validate our results.Our results show that age-selective harvesting is more conducive to sustainable population survival than non-age-selective harvesting. 展开更多
关键词 The logistic population model Selective harvesting Asymptotic stability EXTINCTION
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Theoretical Modeling and Compensation of Errors in Industrial Robot Accuracy and Repeatability
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作者 Zhou Yang 《机械工程与设计(中英文版)》 2025年第2期14-17,共4页
Industrial robots are integral to modern manufacturing systems,enabling high precision,high throughput,and flexibility.However,errors in accuracy and repeatability,which arise from a variety of sources such as mechani... Industrial robots are integral to modern manufacturing systems,enabling high precision,high throughput,and flexibility.However,errors in accuracy and repeatability,which arise from a variety of sources such as mechanical wear,calibration issues,and environmental factors,can significantly impact the performance of industrial robots.This paper aims to explore the theoretical modeling of errors in industrial robot systems and propose compensation strategies to enhance their accuracy and repeatability.Key factors contributing to errors,such as kinematic,dynamic,and environmental influences,are discussed in detail.Additionally,the paper explores various compensation techniques,including geometric error compensation,dynamic compensation,and adaptive control approaches.Through the integration of error modeling and compensation methods,industrial robots can achieve improved performance,ensuring higher operational efficiency and product quality.The paper concludes by highlighting the challenges and future research directions for improving the accuracy and repeatability of industrial robots in practical applications. 展开更多
关键词 Industrial Robots ACCURACY REPEATABILITY Error modeling Compensation Strategies Kinematic Errors Dynamic Errors Adaptive Control
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Special Issue“Recent Developments in Dimension Reduction and Model Checking”——In Honor of Professor Lixing Zhu's Outstanding Contributions in Statistics
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作者 ZHU Liping XU Wangli LI Yingxing 《Journal of Systems Science & Complexity》 2026年第1期1-2,共2页
The proliferation of high-dimensional data and the widespread use of complex models present central challenges in contemporary statistics and data science.Dimension reduction and model checking,as two foundational pil... The proliferation of high-dimensional data and the widespread use of complex models present central challenges in contemporary statistics and data science.Dimension reduction and model checking,as two foundational pillars supporting scientific inference and data-driven decisionmaking,have evolved through the collective wisdom of generations of statisticians.This special issue,titled"Recent Developments in Dimension Reduction and Model Checking for regressions",not only aims to showcase cutting-edge advances in the field but also carries a distinct sense of academic homage to honor the groundbreaking and enduring contributions of Professor Lixing Zhu,a leading scholar whose work has profoundly shaped both areas. 展开更多
关键词 scientific inference model checking model checkingas complex models dimension reduction high dimensional data
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