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Short-and long-term behaviors of drifts in the Callovo-Oxfordian claystone at the Meuse/Haute-Marne Underground Research Laboratory 被引量:5
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作者 G.Armand A.Noiret +1 位作者 J.Zghondi D.M.Seyedi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2013年第3期221-230,共10页
Since 2000, the French National Radioactive Waste Management Agency (ANDRA) has been constructing an Underground Research Laboratory (URL) at Bure (east of the Paris Basin) to perform experiments in order to obt... Since 2000, the French National Radioactive Waste Management Agency (ANDRA) has been constructing an Underground Research Laboratory (URL) at Bure (east of the Paris Basin) to perform experiments in order to obtain in situ data necessary to demonstrate the feasibility of geological repository in the Callovo- Oxfordian claystone. An important experimental program is planned to characterize the response of the rock to different drift construction methods, Before 2008, at the main level of the laboratory, most of the drifts were excavated using pneumatic hammer and supported with rock bolts, sliding steel arches and fiber shotcrete. Other techniques, such as road header techniques, stiff and flexible supports, have also been used to characterize their impacts. The drift network is developed following the in situ major stresses. The parallel drifts are separated enough so as they can be considered independently when their hydromechanical (HM) behaviors are compared. Mine-by experiments have been performed to measure the HM response of the rock and the mechanical loading applied to the support system due to the digging and after excavation. Drifts exhibit extensional (mode I) and shear fractures (modes II and III) induced by excavation works. The extent of the induced fracture networks depends on the drift orientation versus the in situ stress field. This paper describes the drift convergence and deformation in the surrounding rock walls as function of time and the impact of different support methods on the rock mass behavior. An observation based method is finally applied to distinguish the instantaneous and time-dependent parts of the rock mass deformation around the drifts. 展开更多
关键词 Field experiments Claystone Tunnel convergence Induced fractures Short- and long-term behaviors
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Acute histopathological responses and long-term behavioral outcomes in mice with graded controlled cortical impact injury 被引量:2
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作者 Si-Yi Xu Min Liu +7 位作者 Yang Gao Yang Cao Jin-Gang Bao Ying-Ying Lin Yong Wang Qi-Zhong Luo Ji-Yao Jiang Chun-Long Zhong 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第6期997-1003,共7页
While animal models of controlled cortical impact often display short-term motor dysfunction after injury, histological examinations do not show severe cortical damage. Thus, this model requires further improvement. M... While animal models of controlled cortical impact often display short-term motor dysfunction after injury, histological examinations do not show severe cortical damage. Thus, this model requires further improvement. Mice were subjected to injury at three severities using a Pin-Point^(TM)-controlled cortical impact device to establish secondary brain injury mouse models. Twenty-four hours after injury, hematoxylin-eosin staining, Fluoro-Jade B histofluorescence, and immunohistochemistry were performed for brain slices. Compared to the uninjured side, we observed differences of histopathological findings, neuronal degeneration, and glial cell number in the CA2 and CA3 regions of the hippocampus on the injured side. The Morris water maze task and beam-walking test verified long-term(14–28 days) spatial learning/memory and motor balance. To conclude, the histopathological responses were positively correlated with the degree of damage,as were the long-term behavioral manifestations after controlled cortical impact. All animal procedures were approved by the Institutional Animal Care and Use Committee at Shanghai Jiao Tong University School of Medicine. 展开更多
关键词 nerve REGENERATION TRAUMATIC brain INJURY controlled cortical impact HISTOPATHOLOGY behavioral MANIFESTATIONS neural REGENERATION
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Long-term creep of Beishan granite under uniaxial compression
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作者 Chunping Wang Xingguang Zhao +4 位作者 Jianfeng Liu Haiyang Zhang Liang Chen Hongsu Ma Ju Wang 《International Journal of Mining Science and Technology》 2026年第1期79-93,共15页
Investigations into the long-term creep behavior of Beishan granite in uniaxial compression were conducted.Four levels of axial stress(60,70,87,and 95 MPa)were applied to rock specimens.Contrasting with earlier resear... Investigations into the long-term creep behavior of Beishan granite in uniaxial compression were conducted.Four levels of axial stress(60,70,87,and 95 MPa)were applied to rock specimens.Contrasting with earlier research,the long-term creep data in this work present a substantial advancement in the time dimension.Except for the sample subjected to 60 MPa axial loading,which did not fail after a loading duration of 1650 d,the specimens under the other three stresses all failed after sustained constant loading durations of 1204,1023,and 839 d,respectively.A lower envelope of driving stress-ratio for crystalline rocks was obtained,tending towards approximately 0.45 over an infinite time scale.According to the experimental results,as axial stress increases,both the axial strain accumulated in the transient creep process and the strain rate associated with steady-state creep deformation increase exponentially;however,the share of steady-state creep strain remains nearly constant at about82.53%.A novel damage-based creep model was put forward.It provides an enhanced depiction of the comprehensive creep process in rocks,notably improving the accuracy in forecasting the accelerated creep phase,which significantly impacts the long-term stability of engineering structures. 展开更多
关键词 long-term strength Creep model DAMAGE Creep behavior
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Influence of Hf Alloying on Precipitation Behavior of γ' Phase and Tensile Properties of Ni-Cr-Mo Alloy
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作者 Li Linzi Guan Xianjun +1 位作者 Hou Jieshan Zhou Lanzhang 《稀有金属材料与工程》 北大核心 2026年第1期59-66,共8页
The influence of Hf on the precipitation behavior of γ'phase and the subsequent tensile properties of a Ni-Cr-Mo alloy after long-term thermal exposure was investigated.The results reveal that the addition of Hf ... The influence of Hf on the precipitation behavior of γ'phase and the subsequent tensile properties of a Ni-Cr-Mo alloy after long-term thermal exposure was investigated.The results reveal that the addition of Hf increases the average diameter ofγ'phases after thermal exposure at 700℃ for 5000 h,which enhances the critical resolved shear stress required for dislocations to shear the γ'phases in the Ni-Cr-Mo alloy.Simultaneously,element Hf incorporated into the γ'phases increases the lattice mismatch between the γ'and γ phase,thereby strengthening the coherency strengthening effect.These two factors collectively contribute to the enhanced strength of the alloy.Thus,Hf alloying effectively improves the yield strength of the Ni-Cr-Mo alloy after thermal exposure at 700℃. 展开更多
关键词 Ni-Cr-Mo alloy Hf alloying γ'strengthening long-term thermal exposure dislocations shearing
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Method for Behavior Recognition of Hu Sheep in Intensive Farming Based on HLNC-YOLO
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作者 JI Ronghua CHANG Hongrui +2 位作者 ZHANG Suoxiang LIU Zhongying WU Zhonghong 《农业机械学报》 北大核心 2026年第2期265-275,共11页
Behavior recognition of Hu sheep contributes to their intensive and intelligent farming.Due to the generally high density of Hu sheep farming,severe occlusion occurs among different behaviors and even among sheep perf... Behavior recognition of Hu sheep contributes to their intensive and intelligent farming.Due to the generally high density of Hu sheep farming,severe occlusion occurs among different behaviors and even among sheep performing the same behavior,leading to missing and false detection issues in existing behavior recognition methods.A high-low frequency aggregated attention and negative sample comprehensive score loss and comprehensive score soft non-maximum suppression-YOLO(HLNC-YOLO)was proposed for identifying the behavior of Hu sheep,addressing the issues of missed and erroneous detections caused by occlusion between Hu sheep in intensive farming.Firstly,images of four typical behaviors-standing,lying,eating,and drinking-were collected from the sheep farm to construct the Hu sheep behavior dataset(HSBD).Next,to solve the occlusion issues,during the training phase,the C2F-HLAtt module was integrated,which combined high-low frequency aggregation attention,into the YOLO v8 Backbone to perceive occluded objects and introduce an auxiliary reversible branch to retain more effective features.Using comprehensive score regression loss(CSLoss)to reduce the scores of suboptimal boxes and enhance the comprehensive scores of occluded object boxes.Finally,the soft comprehensive score non-maximal suppression(Soft-CS-NMS)algorithm filtered prediction boxes during the inferencing.Testing on the HSBD,HLNC-YOLO achieved a mean average precision(mAP@50)of 87.8%,with a memory footprint of 17.4 MB.This represented an improvement of 7.1,2.2,4.6,and 11 percentage points over YOLO v8,YOLO v9,YOLO v10,and Faster R-CNN,respectively.Research indicated that the HLNC-YOLO accurately identified the behavior of Hu sheep in intensive farming and possessed generalization capabilities,providing technical support for smart farming. 展开更多
关键词 behavior recognition YOLO loss function attention mechanism
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Effect of Initial Microstructure States on Flow Behavior of Al-Zn-Mg-Cu Alloy During Hot Tensile Deformation
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作者 Wang Shuyan Zhou Yuting +3 位作者 Du Ruibo Long Shuai Lin Haitao Wang Shaoyang 《稀有金属材料与工程》 北大核心 2026年第2期302-314,共13页
To investigate the influence of Al-Zn-Mg-Cu alloy with as-homogenized and as-rolled initial microstructures on the tensile flow behavior,isothermal tensile tests were conducted on a GLEEBLE-3500 isothermal simulator a... To investigate the influence of Al-Zn-Mg-Cu alloy with as-homogenized and as-rolled initial microstructures on the tensile flow behavior,isothermal tensile tests were conducted on a GLEEBLE-3500 isothermal simulator at temperatures of 380-440℃and strain rates of 0.05-1 s^(−1).The Johnson-Cook model,Hensel-Spittel model,strain-compensated Arrhenius model,and critical fracture strain model were established.Results show that through the evaluation of the models using the correlation coefficient(R)and the average absolute relative error,the strain-compensated Arrhenius model can represent the flow behavior of the alloy more accurately.Shear bands are more pronounced in the as-homogenized specimens,whereas dynamic recrystallization is predominantly observed in as-rolled specimens.Fracture morphology analysis reveals that a mixed fracture mechanism is prevalent in the as-homogenized specimen,whereas a ductile fracture mechanism is predominant in the as-rolled specimen.The processing maps indicate that the unstable region is reduced in the as-rolled specimens compared with that in the as-homogenized specimens.The optimal hot working windows for the as-homogenized and as-rolled specimens are determined as 410-440℃/0.14-1 s^(−1)and 380-400℃/0.05-0.29 s^(−1),respectively. 展开更多
关键词 Al-Zn-Mg-Cu alloy tensile flow behavior MICROSTRUCTURE constitutive modelling processing map
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Potential impacts of invasive mussels on long-term carbonate chemistry changes in Lake Michigan
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作者 Chunqi SHEN Jeremy MTESTA Yang SONG 《Journal of Oceanology and Limnology》 2026年第1期125-136,共12页
While oceanic and coastal acidification has gained increased attention,long-term pH trends and their drivers in large freshwater systems remain poorly understood.The Laurentian Great Lakes are the world’s largest fre... While oceanic and coastal acidification has gained increased attention,long-term pH trends and their drivers in large freshwater systems remain poorly understood.The Laurentian Great Lakes are the world’s largest freshwater system,and in many ways resemble marine ecosystems.However,unlike the open ocean and coastal waters where pH has declined due to rising atmospheric CO_(2),no significant pH trends have been observed in the Laurentian Great Lakes,despite significant ecosystem changes driven partly by the invasion of dreissenid mussels.This study examined 41 years of field observations from Lake Michigan to investigate the long-term carbonate chemistry dynamics.Observational results revealed substantial declines in both total alkalinity(TA)and dissolved inorganic carbon(DIC)over the four decades.Mussel shell calcification emerged as the primary mechanism behind these declines,accounting for 97%and 47%of the observed changes in TA and DIC,respectively,lowering water column pH by 0.24 units.Elevated carbon accumulation in soft mussel tissues,coupled with long-term changes in the air-water pCO_(2)gradient during summer,significantly contributed to long-term DIC variations,explaining 18%and 28%of the lake-wide DIC loss.These two mechanisms also resulted in an overall pH increase of 0.09 and 0.12 units,largely offsetting the calcification-driven pH decrease.These findings bridge a gap in acidification research for large freshwater systems and provide valuable insights for comprehensive lake-wide management strategies. 展开更多
关键词 carbonate chemistry freshwater acidification invasive mussel Lake Michigan long-term trend
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Correction: Optimizing Exciton and Charge-Carrier Behavior in Thick-Film Organic Photovoltaics: A Comprehensive Review
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作者 Lu Wei Yaxin Yang +2 位作者 Lingling Zhan Shouchun Yin Hongzheng Chen 《Nano-Micro Letters》 2026年第1期608-608,共1页
Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.Th... Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.The published version showed“Hongzhen Chen”,whereas the correct spelling should be“Hongzheng Chen”.The correct author name has been provided in this Correction,and the original article[1]has been corrected. 展开更多
关键词 charge carrier behavior exciton behavior comprehensive review thick film organic photovoltaics nano micro letters
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Urban-rural differences in residential energy-use behavior and energy-saving awareness:Evidence from a Chinese megacity
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《建筑节能(中英文)》 2026年第2期150-150,共1页
Residential energy-use behavior and energy-saving awareness play a crucial role in sustainable urban energy planning and building energy efficiency,particularly under the pressures of climate change.However,existing s... Residential energy-use behavior and energy-saving awareness play a crucial role in sustainable urban energy planning and building energy efficiency,particularly under the pressures of climate change.However,existing studies often lack comparative analysis of urban-rural differences and tend to focus excessively on behavior patterns while neglecting the dimension of energysaving awareness.With China’s urbanization rate reaching 66.16%,understanding such regional disparities has become increasingly important.To address these research gaps,this study conducts a large-scale survey on space cooling behaviors among residents in Beijing,a representative Chinese megacity.It should be noted that living standards in such megacities are generally higher than the national average,which may shape distinctive energy-use profiles.Analyzing 1573valid samples(1064 urban/442 rural)in 2024,this study employed K-Prototypes and K-Modes clustering to identify typical cooling behavior and energy-saving awareness pattems,followed by Kendall/Chi-square correlation tests and XGBoost importance analysis to determine key influencing factors,with subsequent urban-rural comparative analysis.Results indicate that urban residents are primarily heat-sensitive or heat-tolerant,with a secondary patten of mid-low temperature preference,and generally exhibit long cooling durations;rural behavior is dominated by heat-tolerant type,followed by heat-sensitive,mid-low temperature preference,and never-on types as secondary patterns;both urban and rural areas exhibit energy-savingawareness characterized by low consumption-lowwillingness,though urban areas show marginally higher motivation;energy-saving awareness correlates with cooling behavior in rural areas,but this relationship weakens significantly in urban contexts. 展开更多
关键词 behavior patterns such regional disparities energy saving awareness residential energy use behavior climate change urban rural differences China Beijing
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Analysis of Long-term Prognosis and Cosmetic Outcomes of Breast-conserving Surgery Combined with Sentinel Lymph Node Biopsy for Early-stage Breast Cancer
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作者 Yuedong Zhang 《Proceedings of Anticancer Research》 2026年第1期101-108,共8页
Objective:To investigate the long-term prognosis and postoperative cosmetic outcomes of breast-conserving surgery combined with sentinel lymph node biopsy in patients with early-stage breast cancer,providing a referen... Objective:To investigate the long-term prognosis and postoperative cosmetic outcomes of breast-conserving surgery combined with sentinel lymph node biopsy in patients with early-stage breast cancer,providing a reference for the selection of clinical treatment plans.Methods:A retrospective analysis was conducted on the clinical data of 68 patients with early-stage breast cancer admitted from January 2022 to December 2025.Based on the surgical approach,patients were divided into an observation group(breast-conserving surgery+sentinel lymph node biopsy)and a control group(other surgical methods such as modified radical mastectomy/total mastectomy).Clinical and pathological characteristics,incidence of postoperative complications,follow-up prognosis,and satisfaction with cosmetic outcomes were compared between the two groups.Results:Among the 68 patients,41 were in the observation group and 27 in the control group.The average age of patients in the observation group was(54.32±8.15)years,while that in the control group was(62.45±9.76)years.The average tumor size in the observation group was(1.86±0.72)cm,compared to(3.21±1.45)cm in the control group.The incidence of postoperative complications in the observation group was 9.76%,significantly lower than that in the control group at 33.33%(P<0.05).The 6-month disease-free survival rate was 95.12%in the observation group and 88.89%in the control group,with no statistically significant difference between the two groups(P>0.05).The excellent and good rate of cosmetic outcomes in the observation group was 87.80%,significantly higher than that in the control group at 29.63%(P<0.05).Conclusion:Breast-conserving surgery combined with sentinel lymph node biopsy for early-stage breast cancer can achieve long-term prognostic outcomes comparable to those of traditional radical surgery,with the advantages of fewer postoperative complications and superior cosmetic results.This approach is worthy of clinical promotion and application,particularly for early-stage breast cancer patients who have a demand for preserving breast morphology. 展开更多
关键词 Early-stage breast cancer Breast-conserving surgery Sentinel lymph node biopsy long-term prognosis Cosmetic results
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ADCP-YOLO:A High-Precision and Lightweight Model for Violation Behavior Detection in Smart Factory Workshops
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作者 Changjun Zhou Dongfang Chen +1 位作者 Chenyang Shi Taiyong Li 《Computers, Materials & Continua》 2026年第3期1895-1919,共25页
With the rapid development of smart manufacturing,intelligent safety monitoring in industrial workshops has become increasingly important.To address the challenges of complex backgrounds,target scale variation,and exc... With the rapid development of smart manufacturing,intelligent safety monitoring in industrial workshops has become increasingly important.To address the challenges of complex backgrounds,target scale variation,and excessive model parameters in worker violation detection,this study proposes ADCP-YOLO,an enhanced lightweight model based on YOLOv8.Here,“ADCP”represents four key improvements:Alterable Kernel Convolution(AKConv),Dilated-Wise Residual(DWR)module,Channel Reconstruction Global Attention Mechanism(CRGAM),and Powerful-IoU loss.These components collaboratively enhance feature extraction,multi-scale perception,and localization accuracy while effectively reducing model complexity and computational cost.Experimental results show that ADCP-YOLO achieves a mAP of 90.6%,surpassing YOLOv8 by 3.0%with a 6.6%reduction in parameters.These findings demonstrate that ADCP-YOLO successfully balances accuracy and efficiency,offering a practical solution for intelligent safety monitoring in smart factory workshops. 展开更多
关键词 YOLO violation behavior detection AKConv CRGAM DWR Powerful-IoU
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Corrosion behavior of 650 MPa high strength low alloy steel in industrial polluted environments containing different concentrations of Cl^(-)
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作者 Lianjun Hao Xiaokun Cai +4 位作者 Tianqi Chen Chenyu Zhang Chao Liu Xuequn Cheng Xiaogang Li 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期228-241,共14页
This study utilizes wet/dry cyclic corrosion testing combined with corrosion big data technology to investigate the mechanism by which chloride ions(Cl^(-))influence the corrosion behavior of 650 MPa high-strength low... This study utilizes wet/dry cyclic corrosion testing combined with corrosion big data technology to investigate the mechanism by which chloride ions(Cl^(-))influence the corrosion behavior of 650 MPa high-strength low-alloy(HSLA)steel in industrially polluted environments.The corrosion process of 650 MPa HSLA steel occurred in two distinct stages:an initial corrosion stage and a stable corrosion stage.During the initial phase,the weight loss rate increased rapidly owing to the instability of the rust layer.Notably,this study demonstrated that 650 MPa HSLA steel exhibited superior corrosion resistance in Cl-containing environments.The formation of a corrosion-product film eventually reduced the weight-loss rate.However,the intrusion of Cl^(-)at increasing concentrations gradually destabilized theα/γ^(*)phases of the rust layer,leading to a looser structure and lower polarization resistance(R_(p)).The application of corrosion big data technology in this study facilitated the validation and analysis of the experimental results,offering new insights into the corrosion mechanisms of HSLA steel in chloride-rich environments. 展开更多
关键词 HSLA steel CHLORINE corrosion behavior corrosion big data
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Long-term outcomes following lens extraction surgery in acute primary angle closure
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作者 Yi-Ning Guo Jing Ding +3 位作者 Hao-Ran Ai Xin-Zuo Zhou Xue-Min Li Chun Zhang 《International Journal of Ophthalmology(English edition)》 2026年第2期281-290,共10页
AIM:To investigate the long-term outcomes in acute primary angle closure(APAC)patients treated with lens extraction(LE)surgery and to identify risk factors for glaucomatous optic neuropathy(GON).METHODS:In this longit... AIM:To investigate the long-term outcomes in acute primary angle closure(APAC)patients treated with lens extraction(LE)surgery and to identify risk factors for glaucomatous optic neuropathy(GON).METHODS:In this longitudinal observational study,detailed medical histories of APAC patients and comprehensive ophthalmic examinations at final followup were collected.Logistic regression analysis was performed to identify predictors of blindness.Univariate and multivariate linear regression analyses were conducted to determine risk factors associated with visual outcomes.RESULTS:This study included 39 affected eyes of 31 subjects(26 females)with an average age of 74.1±8.0y.At 6.7±4.2y after APAC attack,2(5.7%)eyes had bestcorrected visual acuity(VA)worse than 3/60.Advanced glaucomatous visual field loss was observed in 15(39.5%)affected eyes and 5(25.0%)fellow eyes.Nine affected eyes(23.7%)had GON,and 11(28.9%)were blind.Six(15.4%)affected eyes and 2(9.1%)fellow eyes had suspicious progression.A significantly higher blindness rate in factory workers compared to office workers.Logistic regression identified that worse VA at attack(OR 10.568,95%CI 1.288-86.695;P=0.028)and worse early postoperative VA(OR 13.214,95%CI 1.157-150.881;P=0.038)were risk factors for blindness.Multivariate regression showed that longer duration of elevated intraocular pressure(P=0.004)and worse early postoperative VA(P=0.009)were associated with worse visual outcomes.CONCLUSION:Despite LE surgery,some APAC patients experience continued visual function deterioration.Lifelong monitoring is necessary.Target pressure and progression rates should be re-evaluated during follow-up. 展开更多
关键词 acute primary angle closure lens extraction surgery long-term follow-up visual impairment glaucomatous optic neuropathy
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Long-term Mechanism and Implementation Path of Increasing Income of Rural Low-income Population in Zhejiang Province from the Perspective of Common Prosperity
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作者 Peiyi YE 《Asian Agricultural Research》 2026年第2期23-26,共4页
Taking the rural low-income population of Zhejiang Province as its subject, this paper examines how to build a sustainable income-growth mechanism and identify feasible implementation paths within the context of the c... Taking the rural low-income population of Zhejiang Province as its subject, this paper examines how to build a sustainable income-growth mechanism and identify feasible implementation paths within the context of the common prosperity strategy. The research identifies key obstacles to income expansion, including an undiversified industrial structure, insufficient human capital, and a lack of robust social protection. These call for systemic solutions featuring institutional innovation, resource consolidation, and capability enhancement. Building on Zhejiang's experience as a common prosperity demonstration zone, the article constructs an integrated framework centered on four pillars: industrial empowerment, education upgrading, social security reinforcement, and digital coordination. It further offers concrete policy proposals involving the cultivation of localized industries, vocational skill training, enhanced safety nets, and the adoption of digital tools. The study thus offers both theoretical insights and practical paradigms for tackling the challenge of raising incomes in low-income rural areas. 展开更多
关键词 Common prosperity Rural low-income population long-term mechanism of increasing income Implementation path Zhejiang Province
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Volume change and creep behaviors related to stress-phase transition path in methane hydrate-bearing silty sand
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作者 Jiazuo Zhou Qi Fan +1 位作者 Zhenyu Zhu Changfu Wei 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1526-1540,共15页
The volume change behavior of natural gas hydrate-bearing sediment is essential as it influences settlement,strength,and stiffness,which directly affect the stability of hydrate reservoirs during hydrate extraction or... The volume change behavior of natural gas hydrate-bearing sediment is essential as it influences settlement,strength,and stiffness,which directly affect the stability of hydrate reservoirs during hydrate extraction or in response to environmental changes.The volume change is influenced not only by stress but also by the formation and dissociation of hydrates.This study adopted a customized apparatus for one-dimensional compression tests,allowing independent control of gas pressure and effective stress.Tests were conducted on samples with different hydrate saturations along various temperature-gas pressure-effective stress paths,yielding some conclusions related to compressibility and creep.An unusual phenomenon was observed under low-stress conditions:hydrate formation led to shrinkage rather than expansion.Three potential mechanisms behind this occurrence were discussed.As hydrate saturation increases,the yield stress rises while the compression and swelling indexes remain minimally affected.After hydrate dissociation,the compression curve of hydrate-bearing sediment drops to that of hydrate-free sediment.Once hydrate is formed,the compression curve of hydrate-free sediment gradually approaches that of hydrate-bearing sediment during the subsequent loading.Under low-stress conditions,the creep of both hydrate-free and hydrate-bearing sediments is very weak.However,when stress increases,significantly beyond the yield stress,the creep of both sediments increases significantly,with hydrate-bearing sediment exhibiting much greater creep than hydrate-free sediment. 展开更多
关键词 Hydrate-bearing sediment Phase transition Volume change Creep behavior
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Characterizing the dynamic behavior and progressive damage evolution of carbonaceous slate under cyclic impact loading
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作者 Zhuang Li Nuwen Xu +4 位作者 Zhiqiang Sun Huabo Xiao Can Yang Huaizhong Liu Biao Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1060-1072,共13页
Drilling and blasting tunneling is a cyclic process in which tunnel rock undergoes repeated blast loading,affecting its dynamic characteristics,energy evolution,and damage progression.To explore the dynamic mechanical... Drilling and blasting tunneling is a cyclic process in which tunnel rock undergoes repeated blast loading,affecting its dynamic characteristics,energy evolution,and damage progression.To explore the dynamic mechanical properties and damage mechanisms of carbonaceous slate under cyclic impact loads of varying intensities,cyclic dynamic tests are conducted using a triaxial split Hopkinson pressure bar.This study analyzes the stress-strain relationship,energy damage evolution,and macro-to-micro failure characteristics.The results show that peak stress and strain are significantly influenced by impact intensity and the number of impacts.The initial dynamic stress is positively correlated with the impact intensity,but with more impact,the dynamic stress decreases while the peak strain increases.Energy evolution follows a pattern of"slow growthfluctuating growthrapid growth,"with the crack initiation stress and its proportion decreasing.CT and SEM analyses reveal that as the impact intensity increases,failure becomes more chaotic,the fracture volume increases,and the fracture mode shifts from interlayer and intergranular to through-layer and trans-granular fractures.These findings provide an experimental basis for soft rock tunnel stability analysis. 展开更多
关键词 Split Hopkinson pressure bar Cyclic impact Dynamic behavior Cumulative damage MICROSTRUCTURE
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Compliance with Three Movement Behaviors and Psychological Health among Adults with Diabetes
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作者 Wenjiao Li Shiliang Chen +2 位作者 Shihui Chen Xinxing Li Yanjie Zhang 《International Journal of Mental Health Promotion》 2026年第2期68-82,共15页
Objectives:24-h movement behaviors(24-HMB),encompassing physical activity,sedentary behavior,and sleep duration,are increasingly regarded as interrelated and important factors for mental health.However,evidence on the... Objectives:24-h movement behaviors(24-HMB),encompassing physical activity,sedentary behavior,and sleep duration,are increasingly regarded as interrelated and important factors for mental health.However,evidence on the comprehensive association of these behaviors with mental health in adults with diabetes in developing countries remains scarce.This study examined the association between 24-HMB guidelines and psychological health among adults with diabetes in developing countries.Methods:Data were retrieved from the World Health Organization’s study on Global Aging and Adult Health Survey dataset.Adults(N=1905)diagnosed with diabetes from five low-and middle-income countries were included.The exposure of interest was adherence to 24-HMB guidelines,depression,cognition,and quality of life(QoL).Multiple logistic and multiple linear regression analyses were used to examine the association between meeting 24-HMB guidelines and depression,cognition,and QoL,respectively.Results:This cross-sectional study revealed that 28.61%complied with all three 24-HMB guidelines.Diabetic patients who met more numbers of 24-HMB guidelines had lower depression risk(OR=0.74,95%CI:0.61 to 0.91,p=0.004),greater cognition(β=0.42,95%CI:0.25 to 0.60,p<0.001),and QoL(β=1.30,95%CI:1.04 to 1.55,p<0.001)with the non-compliant population.For specific combinations,meeting all three guidelines were significantly associated with lower odds of depression,improved cognitive function,and enhanced QoL(all p<0.001).Conclusion:These findings support that meeting 24-HMB guidelines in a single or combined movement behaviors was significantly related to reduced risk of depression,enhanced cognitive function,and improved QoL among individuals with diabetes. 展开更多
关键词 Movement behaviors diabetes mellitus mental health quality of life SLEEP
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Flowback Behavior of Deep Coalbed Methane Horizontal Wells
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作者 Wei Sun Yanqing Feng +4 位作者 Yuan Wang Zengping Zhao Qian Wang Xiangyun Li Dong Feng 《Fluid Dynamics & Materials Processing》 2026年第1期173-191,共19页
Significant differences exist between deep and medium-shallow coalbed methane(CBM)reservoirs.The unclear understanding of flowback and production behavior severely constrains the development of deep CBM resources.To a... Significant differences exist between deep and medium-shallow coalbed methane(CBM)reservoirs.The unclear understanding of flowback and production behavior severely constrains the development of deep CBM resources.To address this challenge,guided by the gas-liquid two-phase flow theory in ultra-low permeability reservoirs,and integrating theoretical analysis,numerical simulation,and insights from production practices,this study classifies the flowback and production stages of deep CBM well considering the Daning-Jixian Block,Eastern Ordos Basin as a representative case.We summarize the flowback characteristics for each stage and establish a standard flowback production type curve,aiming to guide field operations.The results indicate that:(a)The production process of deep CBM horizontal wells can be divided into five distinct stages:initial single-phase water dewatering stage,initial gas appearance to peak water production stage,gas breakthrough to peak gas production stage,stable production and decline stage,and low-rate production stage.(b)Based on reservoir energy,two standard type curves for horizontal well flowback production are established:the‘Sufficient Reservoir Energy’type and the‘Insufficient Reservoir Energy’type.The former achieves a higher initial gas rate(up to 12×10^(4)m^(3)/d)but exhibits poorer stability,while the latter achieves a lower stable rate(up to 8×10^(4)m^(3)/d)but demonstrates stronger stability.Numerical simulation confirms these behavioral patterns and reveals the underlying mechanisms related to the effectively drained area where pressure is significantly depleted.The findings from this study have guided the flowback production operations in 53 deep CBM wells with positive results,demonstrating high potential for broad application. 展开更多
关键词 Daning-Jixian Block deep coalbed methane horizontal well reservoir energy flowback production behavior
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Self-management and help-seeking behavior for gastroesophageal reflux symptoms:A population-based survey
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作者 Lotte J Huibertse Jasmijn Sijben +1 位作者 Yonne Peters Peter D Siersema 《World Journal of Gastroenterology》 2026年第2期124-134,共11页
BACKGROUND Despite societal guidelines recommending targeted screening for Barrett’s esophagus(BE)and esophageal adenocarcinoma(EAC)in individuals with gastroesophageal reflux symptoms(GERS),screening adherence is su... BACKGROUND Despite societal guidelines recommending targeted screening for Barrett’s esophagus(BE)and esophageal adenocarcinoma(EAC)in individuals with gastroesophageal reflux symptoms(GERS),screening adherence is suboptimal.Current screening approaches fail to identify individuals not seeking medical consultation for GERS or whose GERS are managed with‘over-the-counter’(OTC)acid suppressant therapies.AIM To assess patients’self-management and help-seeking behavior for GERS.METHODS This cross-sectional study collected data from the Dutch general population aged 18-75 years between January and April 2023 using a web-based survey.The survey included questions regarding self-management(e.g.,use of acid suppressant therapy with or without prescription)and help-seeking behavior(e.g.,consulting a primary care provider)for GERS.Simple random sampling was performed to select individuals within the target age group.In total,18156 randomly selected individuals were invited to participate.The study protocol was registered in ClinicalTrials.gov(identifier:NCT05689918).RESULTS Of the 18156 invited individuals,3214 participants(17.7%)completed the survey,of which 1572 participants(48.9%)reported GERS.Of these,904 participants(57.5%)had never consulted a primary care provider for these symptoms,of which 331 participants(36.6%)reported taking OTC acid suppressant therapy in the past six months and 100 participants(11.1%)fulfilled the screening criteria for BE and EAC according to the European Society of Gastrointestinal Endoscopy Guideline.CONCLUSION The population fulfilling the screening criteria for BE and EAC is incompletely identified,suggesting potential underutilization of medical consultation.Raising public awareness of GERS as a risk factor for EAC is needed. 展开更多
关键词 Gastroesophageal reflux disease AWARENESS SELF-MANAGEMENT Help-seeking behavior Health promotion Patientreported outcomes
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Long-term manure amendment enhances N_(2)O emissions from acidic soil by alleviating acidification and increasing nitrogen mineralization
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作者 Lei Wu Jing Hu +4 位作者 Muhammad Shaaban Jun Wang Kailou Liu Minggang Xu Wenju Zhang 《Journal of Integrative Agriculture》 2026年第1期262-272,共11页
Long-term manure application has the potential to alleviate soil acidification, and increase carbon sequestration and nutrient availability, thus improving cropland fertility. However, the mechanisms behind greenhouse... Long-term manure application has the potential to alleviate soil acidification, and increase carbon sequestration and nutrient availability, thus improving cropland fertility. However, the mechanisms behind greenhouse gas N_(2)O emissions from acidic soil mediated by long-term manure application remain poorly understood. Herein, we investigated N_(2)O emission and its linkage with gross N mineralization and nitrification rates, as well as nitrifying and denitrifying microbes in an acidic upland soil subjected to 36-year fertilization treatments, including an unfertilized control(CK), inorganic fertilizer(F), 2× rate of inorganic fertilizer(2F), manure(M), and the combination of inorganic fertilizer and manure(FM) treatments. Compared to the CK treatment(1.34 μg N kg^(-1) d^(-1)), fertilization strongly increased N_(2)O emissions by 34-fold on average, with more pronounced increases in the manure-amendment(10.6-169 μg N kg^(-1) d^(-1)) than those in the inorganic fertilizer treatments(3.26-5.51 μg N kg^(-1) d^(-1)). The manure amendment-stimulated N_(2)O emissions were highly associated with increased soil pH, mean weight diameter of soil aggregates, substrate availability(e.g., particulate organic carbon, NO_(3)^(-)and available phosphorus), gross N mineralization rates, denitrifier abundances and the(nirK+nirS)/nosZ ratio. These findings suggest that the increased N_(2)O emissions primarily resulted from alleviated acidification, increased substrate availability and improved soil structure, thus enhancing microbial N mineralization and favoring N_(2)O^(-)producing denitrifiers over N_(2)O consumers. Moreover, ammonia-oxidizing bacteria(AOB) rather than ammonia-oxidizing archaea(AOA) positively correlated with soil NO_(3)^(-)concentration and N_(2)O emissions, indicating that nitrification indirectly contributed to N_(2)O production by supplying NO_(3)^(-)for denitrification. Collectively, manure amendment potentially stimulates N_(2)O emissions, primarily resulting from alleviated soil acidification and increased substrate availability, thus enhancing N mineralization and denitrifier-mediated N_(2)O production. Our findings suggest that consideration should be given to the greenhouse gas budgets of agricultural ecosystems when applying manure for managing the pH and fertility of acidic soils. 展开更多
关键词 long-term manure amendment N_(2)O emission nitrogen mineralization denitrification (nirK+nirS)/nosZ
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