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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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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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A peridynamics modeling approach for pre-cracked rock cracking processes under impact by integrating Drucker-Prager plasticity model and efficient contact model
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作者 Jingzhi Tu Nengxiong Xu Gang Mei 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期179-195,共17页
In rock engineering,natural cracks in rock masses subjected to external loads tend to initiate and propagate,leading to potential safety hazards.To investigate the effect of cracking behavior on the mechanical propert... In rock engineering,natural cracks in rock masses subjected to external loads tend to initiate and propagate,leading to potential safety hazards.To investigate the effect of cracking behavior on the mechanical properties of rocks,the cracking processes of pre-cracked rocks have been extensively studied using numerical modeling methods.The peridynamics(PD)exhibits advantages over other numerical methods due to the absence of the requirements for remeshing and external crack growth criterion.However,for modeling pre-cracked rock cracking processes under impact,current PD implementations lack generally applicable rock constitutive models and impact contact models,which leads to difficulties in determining rock material parameters and efficiently calculating impact loads.This paper proposes a non-ordinary state-based peridynamics(NOSBPD)modeling method integrating the Drucker-Prager(DP)plasticity model and an efficient contact model to address the above problems.In the proposed method,the Drucker-Prager plasticity model is integrated into the NOSBPD,thereby equipping NOSBPD with the capability to accurately characterize the nonlinear stress-strain relationship inherent in rocks.An efficient contact model between particles and meshes is designed to calculate the impact loads,which is essentially a coupling method of PD with the finite element method(FEM).The effectiveness of the proposed NOSBPD modeling method is verified by comparison with other numerical methods and experiments.Experimental results indicate that the proposed method can effectively and accurately predict the 3D cracking processes of pre-cracked cracks under impact loading,and the maximum principal stress is the key driver behind wing crack formation in pre-cracked rocks. 展开更多
关键词 Pre-cracked rocks Cracking processes Non-ordinary state-based peridynamics (NOSBPD) Drucker-Prager plasticity model Efficient contact model
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UAV-to-Ground Channel Modeling:(Quasi-)Closed-Form Channel Statistics and Manual Parameter Estimation
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作者 Zeng Linzhou Liao Xuewen +3 位作者 Xie Wenwu Ma Zhangfeng Xiong Baiping Jiang Hao 《China Communications》 2026年第1期47-66,共20页
(Quasi-)closed-form results for the statistical properties of unmanned aerial vehicle(UAV)airto-ground channels are derived for the first time using a novel spatial-vector-based method from a threedimensional(3-D)arbi... (Quasi-)closed-form results for the statistical properties of unmanned aerial vehicle(UAV)airto-ground channels are derived for the first time using a novel spatial-vector-based method from a threedimensional(3-D)arbitrary-elevation one-cylinder model.The derived results include a closed-form expression for the space-time correlation function and some quasi-closed-form ones for the space-Doppler power spectrum density,the level crossing rate,and the average fading duration,which are shown to be the generalizations of those previously obtained from the two-dimensional(2-D)one-ring model and the 3-D low-elevation one-cylinder model for terrestrial mobile-to-mobile channels.The close agreements between the theoretical results and the simulations as well as the measurements validate the utility of the derived channel statistics.Based on the derived expressions,the impacts of some parameters on the channel characteristics are investigated in an effective,efficient,and explicable way,which leads to a general guideline on the manual parameter estimation from the measurement description. 展开更多
关键词 channel characteristics geometry-based stochastic model manual parameter estimation UAV channel modeling
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Dynamic modeling and analysis of an in-space cable-driven manipulator for on-orbit servicing
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作者 Yiya WANG Bo ZHANG Minghe SHAN 《Chinese Journal of Aeronautics》 2026年第2期609-625,共17页
In-space cable-driven manipulators exhibit several advantages,such as a large range of motion,high dexterity,and lightweight structure.However,kinematic and dynamic analysis play an essential role in designing a cable... In-space cable-driven manipulators exhibit several advantages,such as a large range of motion,high dexterity,and lightweight structure.However,kinematic and dynamic analysis play an essential role in designing a cable-driven manipulator.In this paper,the kinematic analysis of a type of cable-driven manipulator is performed,and a motion planning scheme is conducted to actuate this manipulator.Moreover,a flexible multi-body dynamic model of a cable-driven manipulator considering the frictional contact between the cables and pulleys is established.To describe properties such as flexibility,vibration,and variable length of the cable,this paper utilizes reducedorder beam elements of the Absolute Nodal Coordinates Formulation(ANCF)in Arbitrary Lagrangian Eulerian(ALE)framework.Additionally,a virtual element is introduced to model the contact segment in the cable-pulley system.A tension decay factor is employed to account for the friction in the contact segment.To validate the proposed method,a semi-analytical model based on D'Alembert's principle is established.Cross-verification is performed to validate the accuracy of both models.The model is further applied to simulate the rotation of the cable-driven manipulator with different structural parameters and frictional factors.The results from the analyses provide valuable guidance for the design and motion control of the in-space cable-driven manipulator.Finally,a prototype of a single module is manufactured and tested.Ground experiments are carried out to verify the kinematic and dynamic models. 展开更多
关键词 Cable-driven manipulator Dynamic models Cable-pulley system Arbitrary Lagrangian Eulerian(ALE)formulation Frictional contact modeling
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QingNangTCM:a parameter-efficient fine-tuning large language model for traditional Chinese medicine
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作者 Xuming Tong Liyan Liu +7 位作者 Yanhong Yuan Xiaozheng Ding Huiru Jia Xu Yang Sio Kei Im Mini Han Wang Zhang Xiong Yapeng Wang 《Digital Chinese Medicine》 2026年第1期1-12,共12页
Objective To develop QingNangTCM,a specialized large language model(LLM)tailored for expert-level traditional Chinese medicine(TCM)question-answering and clinical reasoning,addressing the scarcity of domain-specific c... Objective To develop QingNangTCM,a specialized large language model(LLM)tailored for expert-level traditional Chinese medicine(TCM)question-answering and clinical reasoning,addressing the scarcity of domain-specific corpora and specialized alignment.Methods We constructed QnTCM_Dataset,a corpus of 100000 entries,by integrating data from ShenNong_TCM_Dataset and SymMap v2.0,and synthesizing additional samples via retrieval-augmented generation(RAG)and persona-driven generation.The dataset comprehensively covers diagnostic inquiries,prescriptions,and herbal knowledge.Utilizing P-Tuning v2,we fine-tuned the GLM-4-9B-Chat backbone to develop QingNangTCM.A multidimensional evaluation framework,assessing accuracy,coverage,consistency,safety,professionalism,and fluency,was established using metrics such as bilingual evaluation understudy(BLEU),recall-oriented understudy for gisting evaluation(ROUGE),metric for evaluation of translation with explicit ordering(METEOR),and LLM-as-a-Judge with expert review.Qualitative analysis was conducted across four simulated clinical scenarios:symptom analysis,disease treatment,herb inquiry,and failure cases.Baseline models included GLM-4-9BChat,DeepSeek-V2,HuatuoGPT-II(7B),and GLM-4-9B-Chat(freeze-tuning).Results QingNangTCM achieved the highest scores in BLEU-1/2/3/4(0.425/0.298/0.137/0.064),ROUGE-1/2(0.368/0.157),and METEOR(0.218),demonstrating a balanced and superior normalized performance profile of 0.900 across the dimensions of accuracy,coverage,and consistency.Although its ROUGE-L score(0.299)was lower than that of HuatuoGPT-II(7B)(0.351),it significantly outperformed domain-specific models in expert-validated win rates for professionalism(86%)and safety(73%).Qualitative analysis confirmed that the model strictly adheres to the“symptom-syndrome-pathogenesis-treatment”reasoning chain,though occasional misclassifications and hallucinations persisted when dealing with rare medicinal materials and uncommon syndromes. 展开更多
关键词 Large language model(LLM) Traditional Chinese medicine(TCM) Fine-tuning P-Tuning v2 Clinical decision support
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Predicting cerebral acetylcholine dynamics with huperzine A pharmacokinetics in blood via mPBPK-PD modeling
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作者 Jiaying Wang Yangfan Zhang +7 位作者 Haoqian Wu Siqi Yu Xiaoying Cai Youying Zhang Jian Chen Zixing Chen Xiao Zheng Haiping Hao 《Chinese Journal of Natural Medicines》 2026年第3期349-364,共16页
Huperzine A(HupA) is a highly selective, reversible acetylcholinesterase(AChE) inhibitor that exhibits neuroprotective effects and is clinically used to manage benign memory decline.However, the specific relationship ... Huperzine A(HupA) is a highly selective, reversible acetylcholinesterase(AChE) inhibitor that exhibits neuroprotective effects and is clinically used to manage benign memory decline.However, the specific relationship between the pharmacokinetic(PK) profile of HupA and cerebral acetylcholine(ACh) dynamics remains poorly characterized. Here, we characterize the PK-pharmacodynamic(PD) properties of HupA in rats under both physiological and pathological conditions. Following a single intramuscular injection, HupA exhibits a short halflife but rapid brain penetration, while multiple dosing significantly enhances its brain exposure. In a middle cerebral artery occlusion(MCAO) rat model, HupA demonstrates increased brain distribution. Furthermore, HupA elevates ACh concentrations across multiple brain regions, concurrently modulating several monoamine neurotransmitters. Using a minimal physiologically based pharmacokinetic-pharmacodynamic(mPBPK-PD) modeling approach,cerebral ACh dynamics were accurately predicted based on the pharmacokinetics of HupA in systemic circulation. The developed mPBPK-PD model exhibits robust predictive performance and holds potential for guiding the optimization of clinical dosing regimens and improving the therapeutic efficacy of HupA. 展开更多
关键词 Huperzine A ACETYLCHOLINESTERASE NEUROPROTECTION ACETYLCHOLINE Ischemic stroke mPBPK-PD MCAO model
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Exact Computer Modeling of Photovoltaic Sources with Lambert-W Explicit Solvers for Real-Time Emulation and Controller Verification
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作者 Abdulaziz Almalaq Ambe Harrison +2 位作者 Ibrahim Alsaleh Abdullah Alassaf Mashari Alangari 《Computer Modeling in Engineering & Sciences》 2026年第1期873-891,共19页
We present a computer-modeling framework for photovoltaic(PV)source emulation that preserves the exact single-diode physics while enabling iteration-free,real-time evaluation.We derive two closed-form explicit solvers... We present a computer-modeling framework for photovoltaic(PV)source emulation that preserves the exact single-diode physics while enabling iteration-free,real-time evaluation.We derive two closed-form explicit solvers based on the Lambert W function:a voltage-driven V-Lambert solver for high-fidelity I–V computation and a resistance-driven R-Lambert solver designed for seamless integration in a closed-loop PV emulator.Unlike Taylor-linearized explicit models,our proposed formulation retains the exponential nonlinearity of the PV equations.It employs a numerically stable analytical evaluation that eliminates the need for lookup tables and root-finding,all while maintaining limited computational costs and a small memory footprint.The R-Lambert model is integrated into a buck-converter emulator equipped with a discrete PI regulator,which generates current references directly from sensed operating points,thus supporting hardware-constrained implementation.Comprehensive numerical experiments conducted on six commercial modules from various technologies(mono,poly,and multicrystalline)demonstrate significant accuracy improvements under the IEC EN 50530 near-MPP criterion:the V-Lambert solver reduces the±10%Vmpp band error by up to 61 times compared to an explicit-model baseline.Dynamic simulations under varying irradiance,temperature,and load conditions achieve millisecond-scale settling with accurate trajectory tracking.Additionally,processor-in-the-loop experimental validation on an embedded microcontroller supports the simulation results.By unifying exact analytical modeling with embedded realization,this work advances computer modeling for PV emulation,MPPT benchmarking,and controller verification in integrated renewable energy systems. 展开更多
关键词 Photovoltaic emulators(PVE) explicit PV model(EPVM) IEC EN 50530 Lambert function maximum power point(MPP) PVE integration processor-in-the loop
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Modeling Pruning as a Phase Transition:A Thermodynamic Analysis of Neural Activations
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作者 Rayeesa Mehmood Sergei Koltcov +1 位作者 Anton Surkov Vera Ignatenko 《Computers, Materials & Continua》 2026年第3期2304-2327,共24页
Activation pruning reduces neural network complexity by eliminating low-importance neuron activations,yet identifying the critical pruning threshold—beyond which accuracy rapidly deteriorates—remains computationally... Activation pruning reduces neural network complexity by eliminating low-importance neuron activations,yet identifying the critical pruning threshold—beyond which accuracy rapidly deteriorates—remains computationally expensive and typically requires exhaustive search.We introduce a thermodynamics-inspired framework that treats activation distributions as energy-filtered physical systems and employs the free energy of activations as a principled evaluation metric.Phase-transition-like phenomena in the free-energy profile—such as extrema,inflection points,and curvature changes—yield reliable estimates of the critical pruning threshold,providing a theoretically grounded means of predicting sharp accuracy degradation.To further enhance efficiency,we propose a renormalized free energy technique that approximates full-evaluation free energy using only the activation distribution of the unpruned network.This eliminates repeated forward passes,dramatically reducing computational overhead and achieving speedups of up to 550×for MLPs.Extensive experiments across diverse vision architectures(MLP,CNN,ResNet,MobileNet,Vision Transformer)and text models(LSTM,BERT,ELECTRA,T5,GPT-2)on multiple datasets validate the generality,robustness,and computational efficiency of our approach.Overall,this work establishes a theoretically grounded and practically effective framework for activation pruning,bridging the gap between analytical understanding and efficient deployment of sparse neural networks. 展开更多
关键词 THERMODYNamICS activation pruning model compression SPARSITY free energy RENORMALIZATION
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Characterization of inflammatory pseudotumors in a large animal model of liver cancer
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作者 Erik N.K.Cressman Samantha Hicks +2 位作者 Natalie W.Fowlkes Danielle L.Stolley Maria Sophia Stenkamp 《Animal Models and Experimental Medicine》 2026年第2期344-353,共10页
Background:The development of relevant and robust large animal models of hepatocellular carcinoma is needed to test new therapeutic strategies for this disease.Transgenic approaches hold promise in addressing this com... Background:The development of relevant and robust large animal models of hepatocellular carcinoma is needed to test new therapeutic strategies for this disease.Transgenic approaches hold promise in addressing this complex problem.One such model,the Oncopig,has been reported to develop tumors of up to 4 cm in diameter within 7-14 days at sites of in situ vector inoculation.However,the resulting lesions reportedly contained an extensive inflammatory component that has not been evaluated in detail.Methods:Herein,we describe our results from multiparametric characterization of the lesions generated using liver biopsy cores incubated in vector solution and re-placed in the tissue.The study consisted of 3 animals in 3 cohorts(total of 9 animals)that were evaluated at 14,21,and 28 days.CT imaging,immunohistochemistry,multiplex immunofluorescence,and comprehensive blood analyses were used to quantify composition of the hepatic masses that developed following AdCre inoculation.Results:The tumors were hypovascular on CT and predominantly composed of CD45+cells with a strong lymphohistiocytic component,with no carcinomas identified.Ki-67 staining showed proliferation of CD45+immune cells but no neoplastic component.To provide further insight,the results are evaluated in the context of tumor growth kinetics.Conclusion:While progress has been made in generating targetable lesions,achieving a robust large animal model of liver cancer that faithfully recapitulates the human disease remains a challenging goal. 展开更多
关键词 ANIMALS genetically modified disease models ANIMAL solid tumors SWINE
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Dynamics of a Leslie-Gower Predator-Prey Model with Weak Nonlinear Harvesting and Prey-Taxis
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作者 Lina ZHANG Miao WANG 《Journal of Mathematical Research with Applications》 2026年第2期263-272,共10页
In this paper,the dynamics of a Leslie-Gower predator-prey model with weak nonlin-ear harvesting and prey-taxis is discussed.By comparing and analyzing the differences between ordinary differential systems and chemota... In this paper,the dynamics of a Leslie-Gower predator-prey model with weak nonlin-ear harvesting and prey-taxis is discussed.By comparing and analyzing the differences between ordinary differential systems and chemotaxis systems in the stability of equilibrium points,the influence mechanism of chemotaxis on the dynamic behavior of the system is deeply studied.Theoretical analysis shows that chemotaxis significantly changes the stability characteristics of the system,and the reliability of theoretical results is further verified by numerical simulation. 展开更多
关键词 Leslie-Gower predator-prey model nonlinear harvesting prey-taxis stability
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Incorporating Tropical Cyclone(TC)Translation Speed into the Dynamical Statistical Analog Ensemble Forecast Model for Landfalling TC Disasters to Enhance Its Preassessment Capability
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作者 WANG Wenjing WU Caiming +1 位作者 REN Fumin JIANG Xianling 《Journal of Ocean University of China》 2026年第1期13-26,共14页
In this study,tropical cyclone(TC)translation speed was introduced as a new similarity factor within the generalized initial value(GIV)framework,enhancing the disaster preassessment capability of the dynamical statist... In this study,tropical cyclone(TC)translation speed was introduced as a new similarity factor within the generalized initial value(GIV)framework,enhancing the disaster preassessment capability of the dynamical statistical analog ensemble forecast model for landfalling TC disasters(DSAEF_LTD model).Three TC translation speed indicators most relevant to TC precipitation were incorporated:the maximum speed on Day 1(the first day of TC-induced precipitation and wind occurring on land)and the average and minimum speeds over All Days(all days of TC-induced precipitation and wind occurring on land),all classified using the Kmeans clustering algorithm.Simulation experiments showed that integrating TC translation speed enhanced the model's performance.The model provided a better optimal common scheme,with the TSS UM(sum of threat scores for severe and above and extremely severe and above disasters)increasing by 2.66%(from 0.5117 to 0.5253)compared with the original model.More importantly,its preassessment ability improved significantly,with the average TSS UM for independent samples increasing by 6.43%(from 0.6488 to0.6905).The modified model demonstrated greater accuracy in capturing disaster severity and distribution of TCs with significant speed characteristics or with regular tracks.This improvement stemmed from reduced false alarms due to the selection of analogs that are more similar to the target TC.The enhanced preassessment ability can be attributed to the key role of TC translation speed,which significantly influences TC precipitation patterns and improves TC precipitation forecasting.Since precipitation is one of the most crucial disaster-causing factors,better TC precipitation forecasting leads to improved disaster preassessment outcomes.These findings emphasize the promising potential of the DSAEF_LTD model for future TC disaster research and management,contributing to the achievement of the Sustainable Development Goals set by the United Nations 2030 Agenda by strengthening coastal resilience. 展开更多
关键词 tropical cyclone translation speed disaster preassessment DSAEF_LTD model
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Efficacy of an e-education program based on the Health Belief Model on exercise management in women with gestational hypertension:A randomized controlled clinical trial
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作者 Wen Xu Chunfeng Xing +3 位作者 Cong Chen Yanli Huang Piyu Li Jinguo Zhai 《International Journal of Nursing Sciences》 2026年第1期19-26,I0002,共9页
Objectives This study aimed to evaluate the effectiveness of a Health Belief Model(HBM)-based electronic education program combined with individualized supervised exercise in improving exercise adherence and pregnancy... Objectives This study aimed to evaluate the effectiveness of a Health Belief Model(HBM)-based electronic education program combined with individualized supervised exercise in improving exercise adherence and pregnancy outcomes among women with gestational hypertension.Methods A randomized controlled trial was conducted from June 2024 to February 2025 at a tertiary hospital in Shenzhen,China.A total of 142 pregnant women diagnosed with gestational hypertension were randomly assigned to either an experimental group or a control group.The experimental group received routine antenatal care plus a 6-week HBM-based e-education intervention delivered via a mobile application and short messaging service(SMS)reminders,complemented by individualized in-person exercise guidance.The control group received routine antenatal care only.After the 6-week intervention,outcomes were assessed using the 6-min walk test,a disease knowledge and attitudes questionnaire,and the Pregnancy Exercise Self-Efficacy Scale.Primary outcomes included exercise adherence,blood pressure control,incidence of preeclampsia,and other pregnancy-related outcomes.Results A total of 129 participants completed the study(the intervention group[n=65],the control group[n=64]).At 6 weeks post-intervention,the experimental group demonstrated significantly greater improvements than the control group in exercise adherence,blood pressure control,preeclampsia incidence,disease-related knowledge and attitudes,and exercise self-efficacy(all P<0.05).Specifically,participants in the experimental group engaged in more frequent and longer-duration exercise sessions(P<0.05).Their blood pressure was maintained within a more stable and clinically optimal range(systolic:135.2±4.7 mmHg;diastolic:85.4±4.5 mmHg),which was significantly better than that of the control group(systolic:138.4±10.4 mmHg;diastolic:90.9±6.9 mmHg;P<0.05).The incidence of preeclampsia was also significantly lower in the experimental group(P<0.05).Additionally,scores for disease knowledge,attitudes,and exercise self-efficacy were higher in the experimental group(P<0.05).Within-group comparisons revealed that the experimental group showed significant improvements from baseline in exercise frequency,duration,total physical activity,and knowledge/attitude scores(P<0.05),whereas the control group showed no significant changes(P>0.05).Conclusion By embedding video-based education,real-time monitoring,and personalized support into routine prenatal care,this intervention facilitated positive behavioral changes in physical activity among pregnant women.The approach offers a scalable model for clinical nurses to delivering tailored remote exercise support for women with other pregnancy-related complications. 展开更多
关键词 E-EDUCATION Exercise adherence Gestational hypertension Health belief model NURSING Pregnancy outcomes
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THE DYNAMICAL BEHAVIOR OF AN ALMOST PERIODIC SVEIR WARNING MODEL IN A PATCHY ENVIRONMENT
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作者 Binguo WANG Xiaomei MA Yashi WANG 《Acta Mathematica Scientia》 2026年第1期427-458,共32页
The outbreak of infectious diseases is the result of a combination of various factors,including season,the movement of individuals,non-pharmaceutical interventions(NPIs)and the effectiveness and availability of vaccin... The outbreak of infectious diseases is the result of a combination of various factors,including season,the movement of individuals,non-pharmaceutical interventions(NPIs)and the effectiveness and availability of vaccines.Taking these key elements into consideration,an almost periodic SVEIR warning model in the patch environment is here proposed.First,in terms of reproduction numbers,our results imply that if the effective reproduction numbers are R_(e)<1,then the disease dies out;if R_(e)>1,then the disease spreads and leads to local outbreaks.Second,the relationships between R_(e)and C_(s1),C_(a1)(see Section 2)are given by numerical simulations.The numerical results show that even if all people are vaccinated,NPIs are still needed because of the potentially low efficacy of vaccines.Furthermore,the numerical results suggest that NPIs and the strengthening of the effective rate of vaccination are essential in order to achieve herd immunity.Theories involving this model effectively explain the transmission mechanism of most infectious diseases,and provide a valuable theoretical basis for analyzing new infectious diseases in the future.Moreover,this model is helpful for the prevention and control of infectious diseases and the formulation of public health safety policies. 展开更多
关键词 SVEIR model almost periodicity reproduction ratio skew-product semiflow threshold dynamics
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Time-dependent behavior of deep roadway surrounding rock considering damage induced by excavation and mining disturbances:Experiments,modeling,and simulation
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作者 Qingzhe Cui Rongbin Hou +4 位作者 Zhenhua Li Feng Du Xu Chen Boyang Zhang Lielie Li 《International Journal of Mining Science and Technology》 2026年第2期439-456,共18页
In deep coal mining,surrounding rock is subjected to both high in-situ stress and intense mining disturbances,leading to significant time-dependent behavior.Accurately capturing this behavior is essential for predicti... In deep coal mining,surrounding rock is subjected to both high in-situ stress and intense mining disturbances,leading to significant time-dependent behavior.Accurately capturing this behavior is essential for predicting long-term roadway stability,necessitating the development of a reliable constitutive creep model and numerical simulation approach.In this study,creep experiments were conducted on pre-damaged rock with varying initial damage levels to investigate the time-dependent mechanical properties.Based on the experimental results,an accelerated-creep criterion was proposed,and an elastic-viscoplastic creep damage model(EVPCD)was established that simultaneously considers the effects of time-dependent damage and instantaneous damage caused by stress disturbances on rock creep behavior.Subsequently,the effectiveness of the proposed creep model was verified using experimental data,and the secondary development of the EVPCD model was completed based on the FLAC3D platform.Following this,a long-term stability analysis method of deep surrounding rock that accounts for excavation-and mining-induced disturbances was proposed.Using the main roadway of Xutuan Coal Mine as a case study,numerical simulations were carried out to investigate the time-dependent deformation and failure characteristics of the surrounding rock following excavation and mining disturbance.Combined with on-site monitoring of the surrounding rock damage areas,the results indicate that the EVPCD outperforms the CVISC and Nishihara models in predicting the time-dependent behavior of deep surrounding rock. 展开更多
关键词 Initial damage Time-dependent damage Creep model Numerical implementation Damage evolution
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Amelioration of behavioral and neural deficits in animal models of neurodegenerative disease by nanoformulations of curcumin and quercetin
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作者 Bridget Martinez Philip V.Peplow 《Neural Regeneration Research》 2026年第8期3311-3322,共12页
Neurodegenerative diseases are increasing in prevalence due largely to aging populations worldwide and improved medical care for the elderly.Currently approved drugs can reduce some of the symptoms of neurodegenerativ... Neurodegenerative diseases are increasing in prevalence due largely to aging populations worldwide and improved medical care for the elderly.Currently approved drugs can reduce some of the symptoms of neurodegenerative diseases but cannot cure them.Inflammation is involved in the development and progression of neurodegenerative diseases,and oxidative stress is implicated in neurodegeneration associated with cognitive decline and age-related cognitive impairment.Polyphenols such as curcumin,quercetin,and resveratrol possess potent anti-inflammatory and antioxidant properties.Nanoformulations of curcumin and quercetin can optimize their pharmacological effects in the treatment of neurodegenerative diseases.Nanocarriers play a crucial role in delivering drugs across the blood-brain barrier,thereby lowering the risk of peripheral side effects.Various nanoforms have been developed to induce bioavailability and solubility of curcumin and quercetin,including nanoparticles and nanoemulsions.The studies reviewed included 17 using curcumin nanoformulations and seven with quercetin nanoformulations and were tested in widely used animal models of Alzheimer’s disease,Parkinson’s disease,Huntington’s disease,and multiple sclerosis.Many of the curcumin and quercetin nanoformulations brought about improvements in learning and memory in behavioral tests of Alzheimer’s disease models and were effective in reducing oxidative stress in the brain.Both nanocurcumin and nanoquercetin decreased the levels of inflammatory markers in the brain.Nanocurcumin formulations improved motor behavior,gait,and memory in Parkinson’s disease models and increased dopaminergic neurons in the striatum and substantia nigra.Furthermore,nanocurcumin improved locomotor activity,memory,and learning,and the number of dendrites of medium spiny neurons in Huntington’s disease models.Nanocurcumin formulations decreased oxidative stress and inflammation in a model of demyelination.Several important limitations were identified in the studies reviewed and these need to be considered in future studies.Also,clinical trials could be performed using the currently available nanoforms of curcumin and quercetin. 展开更多
关键词 animal models behavioral deficits CURCUMIN inflammation nanoformulations neural deficits neurodegeneration oxidative stress QUERCETIN
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Mechanical behavior and damage constitutive model of silty mudstone under thermo-hydro-mechanical interactions
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作者 ZENG Ling CHENG Hui +6 位作者 SONG Jianping XIONG Jianping ZHANG Hongri CHEN Jingcheng WANG Wenguang LI Youjun LIU Jie 《Journal of Mountain Science》 2026年第1期434-452,共19页
Understanding the deterioration behaviors and mechanisms of rocks under thermo-hydromechanical(THM)interactions is crucial for mitigating slope instability.In this study,the physicomechanical properties of silty mudst... Understanding the deterioration behaviors and mechanisms of rocks under thermo-hydromechanical(THM)interactions is crucial for mitigating slope instability.In this study,the physicomechanical properties of silty mudstone subjected to THM interactions were investigated by triaxial tests.The underlying micro-mechanisms were revealed using microscopic tests.The triaxial test results indicate that the strength parameters of silty mudstone decrease by 89.50%(deformation modulus),78.15%(peak strength),70.58%(cohesion),and 48.65%(friction angle)under 16 THM cycles,a load of 300 kPa,and alternating between 0℃water immersion and 60℃drying.The SEM test results indicate that the deterioration of silty mudstone strength primarily results from hydrothermal-expansion softening and cracking driven by the TLHM interactions.The specimens manifest shear failure under confining pressure exceeding 140 kPa.Furthermore,a new constitutive model considering hydrothermalexpansion strain and non-linear deformation characteristics was developed.The discrepancy between the experimentally measured peak strength and the damage constitutive model prediction remains below 5%.The proposed model is verified to be in satisfactory agreement with the experimental results.The self-designed THM apparatus overcomes the limitations of traditional investigations,enabling simultaneous consideration of thermal,hydraulic,and mechanical interactions. 展开更多
关键词 Silty mudstone THM interactions Mechanical properties Damage constitutive model
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Noisy data-driven identification for errors-in-variables MISO Hammerstein nonlinear models
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作者 Jie Hou Haoran Wang +1 位作者 Penghua Li Hao Su 《Control Theory and Technology》 2026年第1期111-126,共16页
In this paper,we consider a multiple-input single-output(MISO)Hammerstein system whose inputs and output are disturbed by unknown Gaussian white measurement noises.The parameter estimation of such a system is a typica... In this paper,we consider a multiple-input single-output(MISO)Hammerstein system whose inputs and output are disturbed by unknown Gaussian white measurement noises.The parameter estimation of such a system is a typical errors-in-variables(EIV)nonlinear system identification problem.This paper proposes a bias-correction least squares(BCLS)identification methods to compute a consistent estimate of EIV MISO Hammerstein systems from noisy data.To obtain the unbiased parameter estimates of EIV MISO Hammerstein system,the analytical expression of estimated bias for the standard least squares(LS)algorithm is derived first,which is a function about the variances of noises.And then a recursive algorithm is proposed to estimate the unknown term of noises variances from noisy data.Finally,based on bias estimation scheme,the bias caused by the correlation between the input–output signals exciting the true system and the corresponding measurement noise,resulting in unbiased parameter estimates of the EIV MISO Hammerstein system.The performance of the proposed method is demonstrated through a simulation example and a chemical continuously stirred tank reactor(CSTR)system. 展开更多
关键词 Biased-corrected least squares ERRORS-IN-VARIABLES MISO Hammerstein models Parameter estimation System identification
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Tail clamping induces anxiety-like behaviors and visceral hypersensitivity in rat models of non-erosive reflux disease
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作者 Mi Lv Xin Liu +6 位作者 Kai-Yue Huang Yu-Xi Wang Zheng Wang Li-Li Han Hui Che Lin Lv Feng-Yun Wang 《World Journal of Psychiatry》 2026年第1期356-368,共13页
BACKGROUND Non-erosive reflux disease(NERD),the main gastroesophageal reflux subtype,features reflux symptoms without mucosal damage.Anxiety links to visceral hypersensitivity in NERD,yet mechanisms and animal models ... BACKGROUND Non-erosive reflux disease(NERD),the main gastroesophageal reflux subtype,features reflux symptoms without mucosal damage.Anxiety links to visceral hypersensitivity in NERD,yet mechanisms and animal models are unclear.AIM To establish a translational NERD rat model with anxiety comorbidity via tail clamping and study corticotropin-releasing hormone(CRH)-mediated neuroimmune pathways in visceral hypersensitivity and esophageal injury.METHODS Sprague-Dawley(SD)and Wistar rats were grouped into sham,model,and modified groups(n=10 each).The treatments for the modified groups were as follows:SD rats received ovalbumin/aluminum hydroxide suspension+acid perfusion±tail clamping(40 minutes/day for 7 days),while Wistar rats received fructose water+tail clamping.Esophageal pathology,visceral sensitivity,and behavior were assessed.Serum CRH,calcitonin gene-related peptide(CGRP),5-hydroxytryptamine(5-HT),and mast cell tryptase(MCT)and central amygdala(CeA)CRH mRNA were measured via ELISA and qRT-PCR.RESULTS Tail clamping induced anxiety,worsening visceral hypersensitivity(lower abdominal withdrawal reflex thresholds,P<0.05)and esophageal injury(dilated intercellular spaces and mitochondrial edema).Both models showed raised serum CRH,CGRP,5-HT,and MCT(P<0.01)and CeA CRH mRNA expression(P<0.01).Behavioral tests confirmed anxiety-like phenotypes.NERD-anxiety rats showed clinical-like symptom severity without erosion.CONCLUSION Tail clamping induces anxiety in NERD models,worsening visceral hypersensitivity via CRH neuroimmune dysregulation,offering a translational model and highlighting CRH as a treatment target. 展开更多
关键词 Non-erosive reflux disease Anxiety and depression Animal model Tail-clamping Corticotropin hormones
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Damage evolution and constitutive model of limestone with horizontal fissure under the coupled effects of dry-wet cycling and precompression stress
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作者 Shunbo Zhang Zhongping Yang +2 位作者 Yang Gao Miao Liu Shanmeng Hou 《International Journal of Mining Science and Technology》 2026年第1期205-228,共24页
To reveal the influence of coupled effects of dry-wet cycling and precompression stress(CEDWCPS)on the damage evolution of limestone with horizontal fissure(LHF),a series of degradation and uniaxial compression tests ... To reveal the influence of coupled effects of dry-wet cycling and precompression stress(CEDWCPS)on the damage evolution of limestone with horizontal fissure(LHF),a series of degradation and uniaxial compression tests were conducted,and a corresponding piecewise damage constitutive model(PDCM)was established.We found that both dry-wet cycling and precompression stress deteriorate the physical properties,alter the microscopic characteristics,and reduce the mechanical properties of the LHF.These degradations are particularly pronounced under the CEDWCPS,although the magnitude of these changes gradually diminishes with the progression of dry-wet cycling.Meanwhile,they also reduce the deformation degree,prolong the micropore compaction stage,shorten the unstable crack propagation stage,lower the frequency and intensity of AE events,decrease the high-amplitude and high-frequency AE signals,enlarge crack scales,and shorten the crack initiation time.Among the changes of these indicators,the dry-wet cycling plays a dominant role.The crack types of LHF under the CEDWCPS(LHFCEDWCPS)are predominantly tensile cracks,supplemented by shear cracks.The failure mode can be defined as tensileshear composite failure.Finally,the established PDCM effectively captures the nonlinear deformation of micropore and the linear deformation of the matrix in LHFCEDWCPS,with all corresponding R^(2) consistently exceeding 0.97. 展开更多
关键词 Dry-wet cycling Precompression stress Coupled effect Fractured limestone Damage evolution Damage constitutive model
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