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Investigation into the Effect and Microscopic Mechanism of Retarders on Two-component Backfilling Grout in Shield Engineering
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作者 CAI Hongwei MIN Fanlu +5 位作者 YUAN Rui LI Zhen ZHANG Jianfeng WANG Dengfeng ZHANG Yazhou YAO Zhanhu 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期84-95,共12页
To address the issues of short setting time and high bleeding rate of A component,which easily cause pipe plugging and poor grouting performance when a two-component grout is injected synchronously behind the Segmenta... To address the issues of short setting time and high bleeding rate of A component,which easily cause pipe plugging and poor grouting performance when a two-component grout is injected synchronously behind the Segmental Lining,the inorganic retarder sodium pyrophosphate(TSPP)and three organic retarders were added to the A component:sodium citrate(SC),sodium tartrate(ST)and glycerol(GLY).The effect law and microscopic mechanism of viscosity,bleeding rate,setting time,gelling time,compressive strength,and stone rate were investigated.The results revealed that the addition of retarders could enhance the stability and setting time of the A component and increase the gelling time,stone rate,and compressive strength of two-component grout.Among them,the performance of the grout with an SC dosage of 0.1% was superior.The bleeding rate of this grout was reduced to 3.5%,the stone rate of the two-component grout was more than 99%,and the early compressive strength and late compressive strength of this grout were increased by approximately 35% and 7%,respectively.The initial and final setting time of the A component with a TSPP dosage of 0.3% was the longest,which was prolonged to 17 and 26 h,respectively.Microscopic analysis revealed that the four retarders hindered the hydration process of cement through complexation and adsorption,and inhibited the hydration of C_(3)S and the crystallisation of CH.Moreover,they reduced the defects caused by the rapid reaction of water glass and CH on the solid phase structure,enabled the microstructure of the stone body to be denser,and subsequently,enhanced the compressive strength. 展开更多
关键词 backfilling grout two-component grout RETARDER working performance gelling performance microscopic mechanism
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In situ Studies of Electrochemical Energy Conversion and Storage Technologies:From Materials,Intermediates,and Products to Surroundings
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作者 Xing Chen Yu-Lin Sun +2 位作者 Xiu-Mei Lin Jin-Chao Dong Jian-Feng Li 《Nano-Micro Letters》 2026年第5期746-797,共52页
Escalating global energy demands and climate urgency necessitate advanced electrochemical energy conversion and storage technologies(EECSTs)like electrocatalysis and rechargeable batteries.Improving their performance ... Escalating global energy demands and climate urgency necessitate advanced electrochemical energy conversion and storage technologies(EECSTs)like electrocatalysis and rechargeable batteries.Improving their performance relies on elucidating reaction mechanisms and structure-performance relationships via in situ studies.This review summarizes recent in situ studies of EECSTs through a variety of advanced characterization techniques aiming at mapping reaction pathways for the rational design of overall high-performance reaction systems.We outline the principles,capabilities,advantages,and limitations of various in situ techniques.Their applications in in situ studies of fuel cells,water/CO_(2)electrolysis,and lithium batteries are highlighted with representative examples.These studies enable dynamic tracking of chemical and structural evolution of overall reaction systems,including materials,intermediates,products,and surroundings during operation,providing insights critical to rational system design.Future advancements will involve integrating multimodal in situ/operando approaches with artificial intelligence to enable real-time monitoring at practical scales.Such integration promises precise mechanistic insights and robust structure-performance correlations,ultimately accelerating the development of high-performance EECSTs aligned with sustainability and market requirements. 展开更多
关键词 In situ studies ELECTROCATALYSIS Lithium batteries Reaction mechanisms Structure-performance relationships
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Mechanisms and Heterogeneous Effects of Physical Activity on Mental Health:Evidence from the China Family Panel Studies
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作者 Chun-Chieh Hu Shuhan Zheng Youjia Lin 《International Journal of Mental Health Promotion》 2026年第2期83-111,共29页
Objectives:In recent years,mental health has emerged as a pressing public health concern in China,driven by mounting societal pressures and fast-paced urban lifestyles.Physical activity,a well-established means of enh... Objectives:In recent years,mental health has emerged as a pressing public health concern in China,driven by mounting societal pressures and fast-paced urban lifestyles.Physical activity,a well-established means of enhancing psychological well-being,has received growing scholarly and policy attention.This study uses panel data from the 2020 and 2022 waves of the China Family Panel Studies(CFPS)to examine the impact of exercise frequency on mental health(with indicators such as CESD-8 depression scores)among college students and young employees,thereby providing empirical support for targeted mental health interventions.Methods:This study examines the relationship between individual exercise frequency and mental health among college students and young employees,using panel data from the 2020 and 2022 waves of the China Family Panel Studies(CFPS),with the Chinese version of the 8-item Center for Epidemiologic Studies Depression Scale(CESD-8)depression scores,self-rated health,and life satisfaction as outcome variables.Specifically,this study tests three hypotheses:(H1)increased exercise frequency significantly reduces depression symptoms and enhances well-being;(H2)the effects of exercise vary by social roles,with stronger mental health benefits among employed individuals and those with lower education;and(H3)lifestyle factors such as smoking amount,sleep duration,and Body Mass Index(BMI)partially mediate the relationship between exercise and mental health.Employing a two-way fixed effects model,baseline results indicate that a one-unit increase in exercise frequency significantly reduces the CESD-8 score by 0.183 points.To address potential endogeneity and spurious regression concerns,an instrumental variable(IV)approach is further applied.The heterogeneity analysis differentiates between students and employed individuals.Results:Among students,the effects of exercise on mental health are not statistically significant,regardless of education level.In contrast,for the employed,exercise demonstrates a significant positive impact on mental health,with particularly pronounced effects among those with lower educational attainment.These findings underscore the importance of promoting exercise as part of comprehensive mental health strategies.Mediation analysis indicates that the beneficial effect of exercise on mental health is partially transmitted through reductions in adverse health behaviors,especially smoking.Conclusions:Policymakers should integrate physical activity promotion into health interventions,prioritizing vulnerable groups to enhance psychological resilience and foster inclusive,health-oriented development. 展开更多
关键词 Mental health EXERCISE China family panel studies educational level SMOKING
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Study on the strength deterioration characteristics and microscopic mechanisms of moraine soil under freeze-thaw cycles
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作者 Peng-fei Wang Ming-li Li +3 位作者 Ming Chang Jun-lin Jiang Fan Yang Zhi-qiang Zuo 《Journal of Groundwater Science and Engineering》 2026年第1期15-31,共17页
To investigate the strength degradation characteristics and microscopic damage mechanisms of moraine soil under hydro-thermo-mechanical coupling conditions,a series of X-ray Diffraction(XRD),standard triaxial testing,... To investigate the strength degradation characteristics and microscopic damage mechanisms of moraine soil under hydro-thermo-mechanical coupling conditions,a series of X-ray Diffraction(XRD),standard triaxial testing,Scanning Electron Microscopy(SEM),and Nuclear Magnetic Resonance(NMR)experiments were conducted.The mechanical property degradation laws and evolution characteristics of the microscopic pore structure of moraine soil under Freeze-Thaw(F-T)conditions were revealed.After F-T cycles,the stress-strain curves of moraine soil showed a strain-softening trend.In the early stage of F-T cycles(0–5 cycles),the shear strength and elastic modulus exhibited damage rate of approximately 10.33%±0.8%and 16.60%±1.2%,respectively.In the later stage(10–20 cycles),the strength parameters fluctuated slightly and tended to stabilize.The number of F-T cycles was negatively exponentially correlated with cohesion,while showing only slight fluctuation in the internal friction angle,thereby extending the Mohr-Coulomb strength criterion for moraine soil under F-T cycles.The NMR experiments quantitatively characterized the evolution of the internal pore structure of moraine soil under F-T cycles.As the number of F-T cycles increased,fine and micro pores gradually expanded and merged due to the frost-heaving effect during the water-ice phase transition,forming larger pores.The proportion of large and medium pores increased to 59.55%±2.1%(N=20),while that of fine and micro pores decreased to 40.45%±2.1%(N=20).The evolution of pore structure characteristics was essentially completed in the later stage of F-T cycles(10–20 cycles).This study provides a theoretical foundation and technical support for major engineering construction and disaster prevention in the Qinghai-Xizang Plateau. 展开更多
关键词 Moraine soil in the Qinghai-Xizang Plateau F-T cycle Standard triaxial tests soil strength degradation Mohr-Coulomb criterion microscopic pore structure
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Studies on the Microscopic Mechanism of the Thermodynamic Stability of Pesticide Microemulsion 被引量:9
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作者 HUANG Qi-liang, YUAN Hui-zhu and YANG Dai-bin(Institute for Plant Protection , Chinese Academy of Agricultural Sciences , Beijing 100094 , P. R . China ) 《Agricultural Sciences in China》 CAS CSCD 2002年第9期994-997,共4页
The cryo-fracture electron microscope was used to study the micro-structure of pesticide mi-croemulsions. The hydromechanical radius (Rh) and the distribution (fRh) of pesticide microemulsions were determined by photo... The cryo-fracture electron microscope was used to study the micro-structure of pesticide mi-croemulsions. The hydromechanical radius (Rh) and the distribution (fRh) of pesticide microemulsions were determined by photo-correlation spectroscopy. This study showed that the Rh was significantly greater when the ratio of surfactants to water (w/w) decreased to 20/31 from 27/26, and a bicontinuous structure was formed when the ratio dropped to 15/36. These results explained the relationship between pesticide properties and the microscopic structure, and provided a good method for studying the microscopic structure of pesticide formulations. 展开更多
关键词 Pesticide microemulsion Thermodynamic stability microscopic mechanism Cryo-fracture Photo-correlation spectroscopy
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Scanning Tunneling Microscopic and Scanning Tunneling Spectroscopic Studies of Nanocrystalline CdSe Thin Film 被引量:1
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作者 Yuan LIN Rui Feng LIN +2 位作者 Xiao Wen Zhou Jing Bo Zhang Xu Rui Xiao(Institute of Photographic Chemistry, The Chinese Academy of Sciences, Bejing,100101) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第9期831-832,共2页
Nanocrystalline CdSe thin film prepared by chemical solution deposition was imaged in air with a scanning tunnelling microscope(STM). Scanning tunnelling current spectroscopy(STS) was taken at a fixed tip - sample sep... Nanocrystalline CdSe thin film prepared by chemical solution deposition was imaged in air with a scanning tunnelling microscope(STM). Scanning tunnelling current spectroscopy(STS) was taken at a fixed tip - sample separation. Tunnelling current(i) - voltage(v) curve and differential conductance spectrum show an n-type schottky rectifying behaviour and yield a direct measure of band gap energy. An increase of bandgap energy (1.8 - 2.1eV) was measured indicating energy quantization of this particular thin film., 展开更多
关键词 Thin CDSE Scanning Tunneling microscopic and Scanning Tunneling Spectroscopic studies of Nanocrystalline CdSe Thin Film
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Studies on mitochondrial macromolecular syntheses in various organs of aging animals labeled with 3H-precursors as revealed by electron microscopic radioautography
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作者 Tetsuji Nagata 《Advances in Bioscience and Biotechnology》 2010年第4期241-262,共22页
In order to study the aging changes of intramitochondrial macromolecular synthesis in various organs of aging animals during the development and aging, 10 groups of developing and aging mice, each consisting of 3 indi... In order to study the aging changes of intramitochondrial macromolecular synthesis in various organs of aging animals during the development and aging, 10 groups of developing and aging mice, each consisting of 3 individuals, total 30, from fetal day 19 to postnatal newborn at day 1, 3, 9, 14 and adult at month 1, 2, 6, 12 to 24 were injected with 3H-thymidine a DNA precurson, another 10 groups consisting of 3 individuals, total 30, were injected with 3H-uridine a RNA precursor, and another 10 groups of 30 individuals were injected with 3H-leucine a protein precursor, total 90 individuals. Then, all the animals were sacrificed 1 hr after the injections and the liver tissues, the lung tissues, the kidney tissues, the testis and ovary tissues, the adrenal tissues were taken out, fixed and processed for electron microscopic radioautography. On electron microscopic radioautograms obtained from each animal, ten photographs in respective groups, numbers of mitochondria per cell profile area, numbers of labeled mitochondria per cell and the mitochondrial labeling index (LI) labeled with 3H-thymidine showing DNA synthesis, LI labeled with 3H-uridine showing RNA synthesis, and LI labeled with 3H-leucine showing protein synthesis, in various organs, were counted and the results in various organs in respective aging groups were compared, respectively. From the results, it was demonstrated that the numbers of mitochondria in hepatocytes as well as in 3 zones of the adrenal cortex, the zona glomerulosa, fasciculata and reticularis of mice at various ages increased from fetal day 19 to postnatal month 1 due to development and aging of animals. On the other hand, the numbers of labeled mitochondria and the labeling indices of intramitochondrial DNA syntheses incorporating 3H-thymidine in hepatocytes and 3 zones of cortical cells increased from fetal day 19 to postnatal month 1 and decreased to month 24. The numbers of labeled mitochondria and the labeling indices of intramitochondrial RNA syntheses incorporating 3H-uridine in hepatocytes and 3 zones of cortical cells increased from fetal day 19 to postnatal month 1 and decreased to month 24. The numbers of labeled mitochondria and the labeling indices of intramitochondrial RNA syntheses incorporating 3H-uridine in hepatocytes and 3 ones of cortical cells increased from fetal day 19 to postnatal month 1 and decreased to month 24. Moreover, some other organs such as the lung and the testis were also review and discussed. From the results, it was shown that the activity of intramitochnodrial DNA synthesis, RNA synthesis, and protein synthesis in hepatocytes, adrenal cortical cells, pulmonary cells and testicular cells in developing and aging mice as well as some other organs increased and decreased due to development and aging. 展开更多
关键词 MITOCHONDRIAL Macromolecular SYNTHESES AGING ANIMALS Labeled 3H-Precursors ELECTRON microscopic Radioautography
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Dynamic deformation characteristics and microscopic analysis of xanthan gum-treated silty soil during wetting process 被引量:2
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作者 Junran Zhang Mengyi Jia +4 位作者 Tong Jiang Shoji Kato De'an Sun You Gao Zheng Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第2期1149-1162,共14页
The deformation characteristics of silty soils under vibrational loads can easily change due to the wetting process,leading to the failure of roadbed structures.Commonly used methods for improving silty soils in engin... The deformation characteristics of silty soils under vibrational loads can easily change due to the wetting process,leading to the failure of roadbed structures.Commonly used methods for improving silty soils in engineering often yield unsatisfactory economic and ecological outcomes.As an environment-friendly soil improvement material,Xanthan gum has broad application prospects and is therefore considered a solidifying agent for enhancing silty soil properties in the Yellow River Basin.In this study,a series of tests is conducted using a scanning electron microscope and a dynamic triaxial testing apparatus to investigate the microstructure and dynamic deformation characteristics of unsaturated silty soil with varying xanthan gum contents during the wetting process.The results show that xanthan gum effectively fills voids between soil particles and adheres to their surfaces,forming fibrous and network structures.This modification enhances the inherent properties of the silty soil and significantly improves its stability under dynamic loading.Specifically,with increasing xanthan gum content,the dynamic shear modulus increases while the damping ratio decreases.During the wetting process,as suction decreases,the dynamic shear modulus decreases while the damping ratio increases.Xanthan gum reduces the sensitivity of the dynamic deformation characteristics of the treated silty soil to changes in suction levels.Finally,based on the modified Hardin-Drnevich hyperbolic model,a predictive model for the dynamic shear modulus and damping ratio of treated silty soil is proposed,considering the xanthan gum content.These research findings provide a theoretical basis for the construction and maintenance of water conservancy,slope stabilization,and roadbed projects in the Yellow River Basin. 展开更多
关键词 Xanthan gum Unsaturated silty soil dynamic deformation characteristics Scanning electron microscope Water retention characteristics
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Bibliometric analysis on the top one hundred cited studies on gastrointestinal endoscopy 被引量:1
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作者 Jing Sui Jian-Sheng Luo +3 位作者 Chao Xiong Chun-Yong Tang Yan-Hua Peng Rui Zhou 《World Journal of Gastrointestinal Endoscopy》 2025年第1期26-35,共10页
BACKGROUND Gastrointestinal endoscopy has been widely used in the diagnosis and treatment of gastrointestinal diseases.A great many of studies on gastrointestinal endoscopy have been done.AIM To analyze the characteri... BACKGROUND Gastrointestinal endoscopy has been widely used in the diagnosis and treatment of gastrointestinal diseases.A great many of studies on gastrointestinal endoscopy have been done.AIM To analyze the characteristics of top 100 cited articles on gastrointestinal endoscopy.METHODS A bibliometric analysis was conducted.The publications and their features were extracted from the Web of Science Core Collection,Science Citation Index-Expanded database.Excel,Web of Science database and SPSS software were used to perform the statistical description and analysis.VOSviewer software and Map-Chart were responsible for the visualizations.RESULTS The top 100 cited articles were published between 1976 and 2022.The guidelines(52%)and clinical trials(37%)are the main article types,and average publication year of the guidelines is much later than that of the clinical trials(2015 vs 1998).Among the clinical trials,diagnostic study(27.0%),cohort study(21.6%),case series(13.5%)and cross-sectional study(10.8%)account for a large proportion.Average citations of different study types and designs of the enrolled studies are of no significant differences.Most of the 100 articles were published by European authors and recorded by the endoscopic journals(65%).Top journals in medicine,such as the Lancet,New England Journal of Medicine and JAMA,also reported studies in this field.The hot spots of involved diseases include neoplasm or cancer-related diseases,inflammatory diseases,obstructive diseases,gastrointestinal hemorrhage and ulcer.Endoscopic surgery,endoscopic therapy and stent placement are frequently studied.CONCLUSION Our research contributes to delineating the field and identifying the characteristics of the most highly cited articles.It is noteworthy that there is a significantly smaller number of clinical trials included compared to guidelines,indicating potential areas for future high-quality clinical trials. 展开更多
关键词 Gastrointestinal endoscopy GUIDELINE Clinical trial Bibliometric analysis Quality of study
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Science Fiction in Latin America,Interdisciplinary Paradigm,and the Regional Studies for Latin America:An Interview with Joanna Page
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作者 Jiang Yuqin Joanna Page 《外国文学研究》 北大核心 2025年第2期1-12,共12页
Joanna Page is Director of CRASSH and Professor of Latin American Studies at the University of Cambridge.Her research interests are generally connected to the relationship between science and culture in Latin America.... Joanna Page is Director of CRASSH and Professor of Latin American Studies at the University of Cambridge.Her research interests are generally connected to the relationship between science and culture in Latin America.She has also worked on questions of memory,modernity,capitalism,posthumanism,new materialism,decoloniality,ecology,and environmental thought.This interview covers three main aspects:the characteristics of science fiction texts in Latin America,the interdisciplinary research models at the intersection of science,literature,and art,and Latin America as a field of regional studies.Professor Page starts with Argentine science fiction novels and expands the discussion to include graphic novels in Latin America,outlining the panorama of science fiction and its indigenous features.The conversation delves into the literary and technological relationships within Latin American science fiction texts.Building upon this foundation,this interview explores the interdisciplinary research paradigms concerning the relationship between science and culture,aiming to contribute to regional studies by exploring new pathways for interdisciplinary,cross-regional,and trans-media research. 展开更多
关键词 science fiction in Latin America interdisciplinary studies regional studies
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Experimental Studies on the Mechanics of Graphene: A Review
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作者 Pei Zhao 《Acta Mechanica Solida Sinica》 2025年第2期195-217,共23页
Graphene,a two-dimensional material with atomic thickness,holds significant importance in advancing the existing theories of solid mechanics.However,as an intersection of multiple scales,it poses challenges to experim... Graphene,a two-dimensional material with atomic thickness,holds significant importance in advancing the existing theories of solid mechanics.However,as an intersection of multiple scales,it poses challenges to experimental measurements of its mechanical behaviors.This review comprehensively discusses the recent achievements in experimental studies on the mechanics of graphene,focusing on sample preparation,loading design,and measurement techniques.Moreover,personal perspectives on the future development in this field are presented,aiming to provide insights and inspiration for researchers engaged in related studies. 展开更多
关键词 GRAPHENE Experimental mechanics Atomic force microscope Electron microscope Raman spectroscopy
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Hybrid CO_(2) thermal system for post-steam heavy oil recovery:Insights from microscopic visualization experiments and molecular dynamics simulations
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作者 Ning Lu Xiaohu Dong +4 位作者 Haitao Wang Huiqing Liu Zhangxin Chen Yu Li Deshang Zeng 《Energy Geoscience》 2025年第2期233-248,共16页
The hybrid CO_(2) thermal technique has achieved considerable success globally in extracting residual heavy oil from reserves following a long-term steam stimulation process.Using microscopic visualization experiments... The hybrid CO_(2) thermal technique has achieved considerable success globally in extracting residual heavy oil from reserves following a long-term steam stimulation process.Using microscopic visualization experiments and molecular dynamics(MD)simulations,this study investigates the microscopic enhanced oil recovery(EOR)mechanisms underlying residual oil removal using hybrid CO_(2) thermal systems.Based on the experimental models for the occurrence of heavy oil,this study evaluates the performance of hybrid CO_(2) thermal systems under various conditions using MD simulations.The results demonstrate that introducing CO_(2) molecules into heavy oil can effectively penetrate and decompose dense aggregates that are originally formed on hydrophobic surfaces.A stable miscible hybrid CO_(2) thermal system,with a high effective distribution ratio of CO_(2),proficiently reduces the interaction energies between heavy oil and rock surfaces,as well as within heavy oil.A visualization analysis of the interactions reveals that strong van der Waals(vdW)attractions occur between CO_(2) and heavy oil molecules,effectively promoting the decomposition and swelling of heavy oil.This unlocks the residual oil on the hydrophobic surfaces.Considering the impacts of temperature and CO_(2) concentration,an optimal gas-to-steam injection ratio(here,the CO_(2):steam ratio)ranging between 1:6 and 1:9 is recommended.This study examines the microscopic mechanisms underlying the hybrid CO_(2) thermal technique at a molecular scale,providing a significant theoretical guide for its expanded application in EOR. 展开更多
关键词 Heavy oil Hybrid CO_(2)thermal system microscopic visualization experiment Molecular dynamics simulation microscopic mechanism
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New Directions in the Interdisciplinary Studies of Literature and Economics: An Interview with Paul Crosthwaite
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作者 Deng Yingling Paul Crosthwaite 《外国文学研究》 北大核心 2025年第1期1-10,共10页
Professor Paul Crosthwaite,from the School of Literature,Languages,and Cultures at the University of Edinburgh,is a prominent scholar in the interdisciplinary field of literature and economics.He is a co-editor of the... Professor Paul Crosthwaite,from the School of Literature,Languages,and Cultures at the University of Edinburgh,is a prominent scholar in the interdisciplinary field of literature and economics.He is a co-editor of the Palgrave Studies in Literature,Culture,and Economics series and The Cambridge Companion to Literature and Economics(2022).In recent years,he has significantly influenced the intersection of literature and economics,advocating particularly for a shift towards the Economic Humanities.This interview covers:1.The definition and theoretical origin of the Economic Humanities;2.The internal heterogeneity and critical limitations of the New Economic Criticism,and the theoretical advantages and potential development of the Economic Humanities;3.What research paradigms do Environmental Humanities,Medical Humanities,and Digital Humanities provide for the Economic Humanities;4.How literary researchers can work at the interface of the Economic Humanities research.As a novel interdisciplinary interface between literature and economics,Professor Paul Crosthwaite’s concept of the Economic Humanities not only pioneers methodological tools for interdisciplinary studies of literature and economics but also underscores the interpretative potential and disciplinary benefits of literary viewpoints on economics.This underscores the vital role of literature in human knowledge,meriting attention from the literary research academia. 展开更多
关键词 the Economic Humanities interdisciplinary studies of Literature and Economics new directions Paul Crosthwaite
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Trajectory Modelling:A Novel Approach to Dig Value of Longitudinal Cohort Studies
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作者 Siyan Zhan 《Biomedical and Environmental Sciences》 2025年第6期651-652,共2页
Cohort studies are important epidemiological methods to investigate associations between environmental factors,individual characteristics,and disease or other health outcomes.As a paradigm of cohort studies,the Framin... Cohort studies are important epidemiological methods to investigate associations between environmental factors,individual characteristics,and disease or other health outcomes.As a paradigm of cohort studies,the Framingham Heart Study(FHS)is the longest-running cardiovascular epidemiological study,starting in 1948. 展开更多
关键词 epidemiological methods NOVEL DIG cohort studiesthe cohort studies framingham heart study fhs APPROACH TRAJECTORY
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Revealing high-temperature oxidation behavior and structure evolution of SnS:an electron microscopic investigation
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作者 Si-Kang Zheng Zhen-Hua Zhang +8 位作者 Yan-Yan Tao Xiao-Meng Yang Jie Liu Hong-Hui Wang Guang Han Xu Lu Guo-Yu Wang Bin Zhang Xiao-Yuan Zhou 《Rare Metals》 2025年第6期4086-4094,共9页
SnS,a well-known van der Waals chalcogenide,is susceptible to oxidation in high-temperature or highhumidity environments,significantly impacting its functional performance and device stability.Conversely,oxidation can... SnS,a well-known van der Waals chalcogenide,is susceptible to oxidation in high-temperature or highhumidity environments,significantly impacting its functional performance and device stability.Conversely,oxidation can be used as an effective strategy for surface engineering,allowing for structure modulation or design,property tuning and application exploration.However,there is currently a gap in understanding the relationship between the oxidation behavior of SnS,the structure of its oxidized surface,and the dependence on oxidation temperature.In this study,we systematically investigated the evolution of SnS surfaces under thermal oxidation using electron microscopy.The microstructure evolution(e.g.,surface structures,phases,defects,and interface)of SnS during high-temperature oxidation has been fully characterized and studied based on cross-sectional samples.Various surface heterostructures were constructed,including SnO_(2)/SnS,SnO_(2)/SnS_(2)/SnS,and SnO_(2)/Sn_(2)S_(3)/SnS,offering significant potential for the surface functionalization of SnS-based systems.Accordingly,oxidation mechanisms at different stages were elucidated based on the detailed and clear picture of microstructures.This research not only deepens our understanding of the fundamental science of SnS oxidation but also provides valuable insights for preventing and developing surface oxidation engineering in SnS and other van der Waals chalcogenides/materials. 展开更多
关键词 SNS Oxidation Heterogeneous surfaces Electron microscopic investigation Formation mechanism
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Microscopic Modeling and Failure Mechanism Study of Fiber Reinforced Composites Embedded with Optical Fibers
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作者 Lei Yang Jianfeng Wang +2 位作者 Minjing Liu Chunyu Chen Zhanjun Wu 《Computers, Materials & Continua》 2025年第7期265-279,共15页
Embedding optical fiber sensors into composite materials offers the advantage of real-time structural monitoring.However,there is an order-of-magnitude difference in diameter between optical fibers and reinforcing fib... Embedding optical fiber sensors into composite materials offers the advantage of real-time structural monitoring.However,there is an order-of-magnitude difference in diameter between optical fibers and reinforcing fibers,and the detailed mechanism of how embedded optical fibers affect the micromechanical behavior and damage failure processes within composite materials remains unclear.This paper presents a micromechanical simulation analysis of composite materials embedded with optical fibers.By constructing representative volume elements(RVEs)with randomly distributed reinforcing fibers,the optical fiber,the matrix,and the interface phase,the micromechanical behavior and damage evolution under transverse tensile and compressive loads are explored.The study finds that the presence of embedded optical fibers significantly influences the initiation and propagation of microscopic damage within the composites.Under transverse tension,the fiber-matrix interface cracks first,followed by plastic cracking in the matrix surrounding the fibers,forming micro-cracks.Eventually,these cracks connect with the debonded areas at the fiber-matrix interface to form a dominant crack that spans the entire model.Under transverse compression,plastic cracking first occurs in the resin surrounding the optical fibers,connecting with the interface debonding areas between the optical fibers and the matrix to form two parallel shear bands.Additionally,it is observed that the strength of the interface between the optical fiber and the matrix critically affects the simulation results.The simulated damage morphologies align closely with those observed using scanning electron microscopy(SEM).These findings offer theoretical insights that can inform the design and fabrication of smart composite materials with embedded optical fiber sensors for advanced structural health monitoring. 展开更多
关键词 Fiber reinforced composites optical fiber microscopic modeling failure mechanism INTERFACE
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Future Manufacturing with AI-Driven Particle Vision Analysis in the Microscopic World
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作者 Guangyao Chen Fengqi You 《Engineering》 2025年第9期68-84,共17页
Recent advances in artificial intelligence(AI)have led to the development of sophisticated algorithms that significantly improve image analysis capabilities.This combination of AI and microscopic imaging is transformi... Recent advances in artificial intelligence(AI)have led to the development of sophisticated algorithms that significantly improve image analysis capabilities.This combination of AI and microscopic imaging is transforming the way we interpret and analyze imaging data,simplifying complex tasks and enabling innovative experimental methods previously thought impossible.In smart manufacturing,these improvements are especially impactful,increasing precision and efficiency in production processes.This review examines the convergence of AI with particle image analysis,an area we refer to as“particle vision analysis(PVA).”We offer a detailed overview of how this technology integrates into and impacts various fields within the physical sciences and materials sectors,where it plays a crucial role in both innovation and operational improvements.We explore four key areas of advancement-namely,particle classification,detection,segmentation,and object tracking-along with a look into the emerging field of augmented microscopy.This paper also underscores the vital role of the existing datasets and implementations that support these applications,which provide essential insights and resources that drive continuous research and development in this fast-evolving field.Our thorough analysis aims to outline the transformative potential of AI-driven PVA in improving precision in future manufacturing at the microscopic scale and thereby preparing the ground for significant technological progress and broad industrial applications in nanomanufacturing,biomanufacturing,and pharmaceutical manufacturing.This exploration not only highlights the advantages of integrating AI into conventional manufacturing processes but also anticipates the rise of next-generation smart manufacturing,which is set to revolutionize industry standards and operational practices. 展开更多
关键词 Particle vision analysis AI-driven microscopic imaging Smart manufacturing
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Combined microscopic and neuroendoscopic treatment effects on psychological and cognitive outcomes in ruptured intracranial aneurysms
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作者 Li-Ke Shi Xian-Feng Cai +1 位作者 Jian-Qing He Yu-Hai Wang 《World Journal of Psychiatry》 2025年第3期280-287,共8页
Intracranial aneurysms,characterized by focal arterial wall dilation,pose significant neurosurgical challenges due to their potential for rupture and hemorrhage,leading to severe clinical outcomes,including fatality.P... Intracranial aneurysms,characterized by focal arterial wall dilation,pose significant neurosurgical challenges due to their potential for rupture and hemorrhage,leading to severe clinical outcomes,including fatality.Patients often experience profound psychological and social impacts,such as depression,anxiety,and cognitive impairment,affecting their quality of life.Rapid progression and high mortality necessitate timely intervention.Advances in neurosurgical techniques,including microscopic surgery and neuroendoscopy,offer distinct advantages.Microscopic surgery provides precision and direct visualization,while neuroendoscopy ensures minimally invasive access and reduced tissue trauma.Integrating these methods optimizes treatment efficacy and clinical outcomes.AIM To evaluate the impact of combined microscopic and neuroendoscopic techniques on psychological,cognitive outcomes,and quality of life in patients with ruptured intracranial aneurysms.METHODS The study focused on 189 patients with intracranial aneurysm rupture and hemorrhage from January 2020 to May 2024 as the objects of observation and analysis.They were randomly divided into a control group(treated with simple microscope surgery,n=94)and an observation group(treated with microscope combined with neuroendoscopy,n=95).The treatment effects of the two groups were observed,mainly including depression and anxiety scale scores,cognitive function assessment results and quality of life assessment data.RESULTS Before treatment,the depression and anxiety scale scores,cognitive function assessment results and quality of life assessment data of the two groups of patients at different time points were compared,and there was no statistically significant difference(P>0.05).After microscope combined with neuroendoscopy treatment,the study revealed that the observation group surpassed the control group in alleviating depression and anxiety,accelerating cognitive function recovery,and enhancing quality of life,with these differences being statistically significant(P<0.05).CONCLUSION Surgical treatment combined with microscopy and neuroendoscopy has a significant positive effect on the mental health,cognitive function and overall quality of life of patients with intracranial aneurysm rupture and bleeding,can shorten the operation time and treatment time,and provides a new strategic reference for clinical treatment. 展开更多
关键词 MICROSCOPE NEUROENDOSCOPY Intracranial aneurysm Depression and anxiety Cognitive function Quality of life
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Data-driven predictive model of coal permeability based on microscopic fracture structure characterization
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作者 Tianhao Yan Xiaomeng Xu +4 位作者 Jiafeng Liu Yihuai Zhang Muhammad Arif Xiaowei Xu Qiang Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第7期4476-4489,共14页
Accurate prediction of coal reservoir permeability is crucial for engineering applications,including coal mining,coalbed methane(CBM)extraction,and carbon storage in deep unmineable coal seams.Owing to the inherent he... Accurate prediction of coal reservoir permeability is crucial for engineering applications,including coal mining,coalbed methane(CBM)extraction,and carbon storage in deep unmineable coal seams.Owing to the inherent heterogeneity and complex internal structure of coal,a well-established method for predicting permeability based on microscopic fracture structures remains elusive.This paper presents a novel integrated approach that leverages the intrinsic relationship between microscopic fracture structure and permeability to construct a predictive model for coal permeability.The proposed framework encompasses data generation through the integration of three-dimensional(3D)digital core analysis and numerical simulations,followed by data-driven modeling via machine learning(ML)techniques.Key data-driven strategies,including feature selection and hyperparameter tuning,are employed to improve model performance.We propose and evaluate twelve data-driven models,including multilayer perceptron(MLP),random forest(RF),and hybrid methods.The results demonstrate that the ML model based on the RF algorithm achieves the highest accuracy and best generalization capability in predicting permeability.This method enables rapid estimation of coal permeability by inputting two-dimensional(2D)computed tomography images or parameters of the microscopic fracture structure,thereby providing an accurate and efficient means of permeability prediction. 展开更多
关键词 microscopic fracture structure Lattice Boltzmann method Machine learning Coal permeability Predictive model
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Persistently high and fluctuating trajectories of total and somatic depressive symptoms increase diabetes risk:Two prospective cohort studies
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作者 Xue-Lun Zou Chang Zhou 《World Journal of Diabetes》 2025年第8期169-184,共16页
BACKGROUND Depression is a significant risk factor for diabetes,particularly type 2 diabetes.However,depressive symptoms differ from clinical depression.Previous research has not fully considered the relationship betw... BACKGROUND Depression is a significant risk factor for diabetes,particularly type 2 diabetes.However,depressive symptoms differ from clinical depression.Previous research has not fully considered the relationship between the trajectory of depressive symptoms and the risk of developing diabetes over time.AIM To investigate the association between depressive symptoms,their trajectories,and the risk of developing diabetes in two prospective cohort studies.METHODS In the first phase we analyzed the association between depressive symptoms and the risk of developing diabetes separately using the Health and Retirement Study(HRS).Depressive symptom trajectories were assessed by examining changes in depressive symptoms at baseline and again 8 years later.We then identified specific depressive symptom trajectories that increased the risk of diabetes in the second phase.Finally,we confirmed the association between depressive symptoms and their trajectories with diabetes risk using the English Longitudinal Study of Ageing(ELSA)as a validation study.Depressive symptom trajectories were categorized into five states based on changes in the modified 8-item Center for Epidemiological Studies-Depression scores:Persistently high;increasing;fluctuating;decreasing;and persistently low.Diabetes mellitus was defined as self-reported,physician-diagnosed diabetes.Cox proportional hazards models were used to assess hazard ratios(HR)and 95%confidence intervals(CI),adjusting for potential confounders.RESULTS In the first phase a total of 27658 participants were included(HRS:18633,ELSA:9025),among whom 6582 had depressive symptoms(HRS:4547,ELSA:2035),6407 had somatic depressive symptoms(HRS:4414,ELSA:1993),and 26415 had cognitive-affective depressive symptoms(HRS:17755,ELSA:8660).We found that overall depressive symptoms(HRS:HR=1.14,95%CI:1.07-1.22;ELSA:HR=1.18,95%CI:1.03-1.34)and somatic depressive symptoms(HRS:HR=1.14,95%CI:1.07-1.22;ELSA:HR=1.25,95%CI:1.10-1.42)increased the risk of diabetes,while cognitive depressive symptoms were not associated with diabetes risk.Over an 8-year follow-up we identified 19729 trajectories of overall,somatic,and cognitive-affective depressive symptoms(HRS:13918,ELSA:5811).In the second phase we found that persistently high(HRS:HR=1.22,95%CI:1.06-1.40,ELSA:HR=1.54,95%CI:1.16-2.05 in total and HRS:HR=1.24,95%CI:1.07-1.43,ELSA:HR=1.79,95%CI:1.36-2.35 in somatic)and fluctuating(HRS:HR=1.09,95%CI:1.01-1.17,ELSA:HR=1.33,95%CI:1.14-1.55 in total and HRS:HR=1.10,95%CI:1.02-1.18,ELSA:HR=1.31,95%CI:1.13-1.53 in somatic)trajectories of overall and somatic depressive symptoms increased the risk of diabetes,while increasing trajectories may also raise diabetes risk.However,decreasing trajectories were not associated with diabetes risk.Cognitive-affective depressive symptoms showed no association with diabetes risk regardless of trajectory changes.Sensitivity analyses confirmed the reliability of the findings.CONCLUSION Persistently high and fluctuating trajectories of overall and somatic depressive symptoms increased the risk of diabetes,while decreasing trajectories were not associated with diabetes risk.In contrast trajectories of cognitiveaffective depressive symptoms show no relationship with diabetes risk.Focusing on depressive symptom trajectories,particularly those of somatic depressive symptoms,represented a viable strategy for future diabetes prevention. 展开更多
关键词 Depressive symptom Trajectories DIABETES Cohort study EPIDEMIOLOGY
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