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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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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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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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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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Ultrabright quantum dots assisted in vivo NIR-II fluorescence microscopic imaging for brain metastases in triple-negative breast cancer
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作者 Yuxiang Gao Chi Zhang +5 位作者 Lijun Zhu Zhong Du Rong Ma Le Guo Nuernisha Alifu Xueliang Zhang 《Journal of Innovative Optical Health Sciences》 2025年第3期87-98,共12页
Triple-negative breast cancer (TNBC) is an aggressive and often fatal disease, especially since the brain metastasis of TNBC has been a particularly severe manifestation. However, brain metastasis in TNBC at early sta... Triple-negative breast cancer (TNBC) is an aggressive and often fatal disease, especially since the brain metastasis of TNBC has been a particularly severe manifestation. However, brain metastasis in TNBC at early stages often lacks noticeable symptoms, making it challenging to detect. Near-infrared II (NIR-II) fluorescence microscopic imaging obtains long wavelength, which enables reduced scattering, high spatial resolution and minimal autofluorescence, it is also a favorable imaging method for tumor diagnosis. PbS@CdS quantum dots (QDs) are one of the popular NIR-II fluorescence nanoprobes for well brightness. In this study, NIR-II emissive PbS@CdS QDs were utilized and further encapsulated with thiol-terminated poly(ethylene oxide) (SH-PEG, MW = 5000) to form PbS@CdS@PEG QDs nanoparticles (NPs). The obtained PbS@CdS@PEG QDs NPs were then characterized and further studied in detail. The PbS@CdS@PEG QDs NPs had large absorption spectra, exhibited strong NIR-II fluorescence emission at approximately 1300nm, and possessed good NIR-II fluorescence properties. Then, the mice model of early-stage brain metastases of TNBC was established, and the PbS@CdS@PEG QDs NPs were injected into the tumor-bearing mice for NIR-II fluorescence microscopic bioimaging. The brain vessels and tumors of the living mice were detected with high spatial resolution under the NIR-II fluorescence microscopic imaging system with irradiation of 808nm laser. The tumor tissues were further restricted and prepared as thin slices. The NIR-II fluorescence signals were collected from the tumor slices with high spatial resolution and signal-to-background ratio (SBR). Thus, the PbS@CdS@PEG QDs NPs-assisted NIR-II fluorescence microscopic system can effectively achieve targeting brain metastases of TNBC imaging, offering a novel and promising approach for TNBC-specific diagnosis. 展开更多
关键词 NIR-II fluorescence microscopic imaging in vivo imaging fluorescent nanoprobes PbS@CdS quantum dots
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Cross-Cultural Essence of Literary Studies
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作者 Liu Yan Wang Xiaolu 《Contemporary Social Sciences》 2025年第2期12-24,共13页
The hybridity of words in literary texts and the multiplicity of theoretical discourse fundamentally determine the cross-cultural attributes of literary studies.This feature holds significant value for understanding d... The hybridity of words in literary texts and the multiplicity of theoretical discourse fundamentally determine the cross-cultural attributes of literary studies.This feature holds significant value for understanding different cultural traditions and presenting one’s cultural traits in a mutually contextualized manner.By analyzing the cross-cultural essence of literary studies with a focus on word transformation and critical discourse and also emphasizing that literary studies should fully consider the linguistic elements of literary texts,the theoretical origins of critical terminology,and the cultural stance of the researcher,it becomes possible to understand the important role of literary studies in humanistic academic knowledge production. 展开更多
关键词 literary studies CROSS-CULTURAL HYBRIDITY DISCOURSE knowledge production
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Dynamic deformation characteristics and microscopic analysis of xanthan gum-treated silty soil during wetting process
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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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Macro-microscopic deformation evolution of thawing frozen fine-grained soil used in heavy-haul railway subgrades in cold regions
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作者 JianBing Chen ShaoJie Liang +3 位作者 YuZhi Zhang XiaoDong Zhu Meng Wang MingTao Jia 《Research in Cold and Arid Regions》 2025年第2期97-109,共13页
During the thawing process of a railway subgrade,bidirectional thawing complicates water-heat transfer,leading to serious thaw settlement issues under train loads.Focusing on the severely frozen section of the Shuozho... During the thawing process of a railway subgrade,bidirectional thawing complicates water-heat transfer,leading to serious thaw settlement issues under train loads.Focusing on the severely frozen section of the Shuozhou-Huanghua port heavy-haul railway,this study conducted indoor soil-column laterally-limited compression tests on thawing fine-grained soil specimens to analyze the cumulative deformation during thawing.The deformation evolution was examined from both macroscopic and microscopic perspectives.The test results revealed a sig-nificant increase in the water content at the frozen interlayer during thawing,with minimal thaw settlement under no-load conditions.However,under dynamic loads,the thawing soil exhibited rapid settlement during the initial stages of the process.Increasing the dynamic load amplitude did not result in significant additional thaw settlement compression.Particle image velocimetry revealed substantial thaw settlement and compression at the top of thawing soil.Microscopically,the porosity at the top of the specimens significantly decreased,whereas the porosity in the frozen interlayer remained largely unchanged.Under dynamic loading,the specimens exhibited a concentrated distribution of large pores with scattered smaller pores.The phase change from ice to water,combined with dynamic loading,induced particle movement and expanded the inter-particle pore space,leading to macroscopic thaw settlement and soil compression.The findings can provide a theoretical foundation for maintaining and ensuring the safety of railway subgrades in cold regions. 展开更多
关键词 Thawing soil Heavy-haul railway Thaw settlement and compression Particle image velocimetry microscopic testing
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Microscopic and Ultraviolet Spectroscopic Identification of Pyrostegia venusta (Ker-Gawler.) Miers
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作者 Hailin LU Bin LI +3 位作者 Zishu CHAI Zhiying WEI Wencheng WEN Jianning TAN 《Medicinal Plant》 2025年第2期32-34,共3页
[Objectives] To identify Pyrostegia venusta (Ker-Gawler.) Miers by microscope and ultraviolet spectrum. [Methods] The paraffin section, slide section and freehand section were used to make the cross section of the ste... [Objectives] To identify Pyrostegia venusta (Ker-Gawler.) Miers by microscope and ultraviolet spectrum. [Methods] The paraffin section, slide section and freehand section were used to make the cross section of the stem and leaf, and the surface of the leaf and the powder of the root, stem and leaf were made by the conventional method, which were observed under the optical microscope. Ultraviolet-visible spectrum identification was carried out according to a conventional method. [Results] The microscopic identification and ultraviolet-visible absorption characteristics of P. venusta (Ker-Gawler) Miers were described in detail. [Conclusions] This study is expected to provide a reference for the identification of P. venusta(KerGawler)Miers and the establishment of the related quality standard. 展开更多
关键词 microscopic identification Ultraviolet spectroscopic identification Pyrostegia venusta(Ker-Gawler.)Miers Quality standard
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Microscopic-NPR bolt slurry-anchor interface bonding performance
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作者 TAO Zhigang XI Chuanhao +3 位作者 ZHANG Jin WANG Xiang WANG Huan WANG Jiong 《Journal of Mountain Science》 2025年第5期1832-1847,共16页
The excellent bonding performance between bolt and anchor materials is crucial for controlling the deformation of deep-buried surrounding rock and strengthening the rock and soil mass in the slope.This paper conducted... The excellent bonding performance between bolt and anchor materials is crucial for controlling the deformation of deep-buried surrounding rock and strengthening the rock and soil mass in the slope.This paper conducted an anchoring test and ABAQUS numerical simulation of an anchoring system comprising a micro-NPR(microscopic negative Poisson’s ratio)bolt and cement mortar as the anchoring material.The failure mode of this system and the distribution of average bonding strength,axial force,and shear stress along the anchoring depth were studied.We also evaluated the bonding properties at the micro-NPR(microscopic negative Poisson’s ratio)bolt-cement mortar interface.The findings indicate that the cement mortar is partially spalled from the micro-NPR bolt surface.The average bonding strength at the micro-NPR bolt-cement mortar interface is positively correlated with anchoring length and cement mortar strength.In contrast,it exhibits a negative correlation with bolt diameter.The axial force is generated at the starting point of the anchorage and decreases non-uniformly across the anchoring region.The axial force transfers or diffuses toward the deeper sections of the anchoring segment with increasing loads.The shear stress at the micro-NPR bolt-cement mortar interface exhibits a single-peak pattern,i.e.,it climbs to a peak value and decreases along the anchoring depth.The peak position varies with changes in bolt diameter and anchoring length.By comparison,it is independent of cement mortar strength.The simulated bonding properties of the micro-NPR bolt-cement mortar interface are consistent with experimental results.The findings can provide a reference for engineering applications and anchoring design of micro-NPR. 展开更多
关键词 microscopic Negative Poisson Ratio Bolt Bond performance Bolt diameter Anchor length Cement mortar strength
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Comparison of objectively measured and estimated cardiorespiratory fitness to predict all-cause and cardiovascular disease mortality in adults:A systematic review and meta-analysis of 42 studies representing 35 cohorts and 3.8 million observations
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作者 Ben Singh Cristina Cadenas-Sanchez +12 位作者 Bruno G.G.da Costa JoséCastro-Pinero Jean-Philippe Chaput Magdalena Cuenca-García Carol Maher Nuria Marín-Jim enez Ryan McGrath Pablo Molina-García Jonathan Myers Bethany Gower Francisco B.Ortega Justin J.Lang Grant R.Tomkinson 《Journal of Sport and Health Science》 2025年第2期135-148,共14页
Background:Cardiorespiratory fitness(CRF)is a powerful health marker recommended by the American Heart Association as a clinical vital sign.Comparing the predictive validity of objectively measured CRF(the"gold s... Background:Cardiorespiratory fitness(CRF)is a powerful health marker recommended by the American Heart Association as a clinical vital sign.Comparing the predictive validity of objectively measured CRF(the"gold standara")and estimated CRF is clinically relevant because estimated CRF is more feasible.Our objective was to meta-analyze cohort studies to compare the associations of objectively measured,exerciseestimated,and non-exercise-estimated CRF with all-cause and cardiovascular disease(CVD)mortality in adults.Methods:Systematic searches were conducted in 9 databases(MEDLINE,SPORTDiscus,Embase,Scopus,PsycINFO,Web of Science,PubMed,CINAHL,and the Cochrane Library)up to April 11,2024.We included full-text refereed cohort studies published in English that quantified the association(using risk estimates with 95%confidence intervals(95%CIs))of objectively measured,exercise-estimated,and non-exercise-estimated CRF with all-cause and CVD mortality in adults.CRF was expressed as metabolic equivalents(METs)of task.Pooled relative risks(RR)for all-cause and CVD mortality per 1-MET(3.5 mL/kg/min)higher level of CRF were quantified using random-effects models.Results:Forty-two studies representing 35 cohorts and 3,813,484 observations(81%male)(362,771 all-cause and 56,471 CVD deaths)were included.The pooled RRs for all-cause and CVD mortality per higher MET were 0.86(95%CI:0.83-0.88)and 0.84(95%CI:0.80-0.87),respectively.For both all-cause and CVD mortality,there were no statistically significant differences in RR per higher MET between objectively measured(RR range:0.86-0.90)and maximal exercise-estimated(RR range:0.85-0.86),submaximal exercise-estimated(RR range:0.91-0.94),and non-exercise-estimated CRF(RR range:0.81-0.85).Conclusion:Objectively measured and estimated CRF showed similar dose-response associations for all-cause and CVD mortality in adults.Estimated CRF could provide a practical and robust alternative to objectively measured CRF for assessing mortality risk across diverse populations.Our findings underscore the health-related benefits of higher CRF and advocate for its integration into clinical practice to enhance risk stratification. 展开更多
关键词 Cardiorespiratory fitness Cardiovascular diseases Cohort studies Risk assessment ADULT
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CO_(2)-EOR microscopic mechanism under injection-production coupling technology in low-permeability reservoirs
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作者 Zheng Chen Yu-Liang Su +3 位作者 Lei Li Yong-Mao Hao Wen-Dong Wang Chui-Xian Kong 《Petroleum Science》 2025年第2期739-755,共17页
Injection-production coupling(IPC) technology holds substantial potential for boosting oil recovery and enhancing economic efficiency.Despite this potential,discussion on gas injection coupling,especially in relation ... Injection-production coupling(IPC) technology holds substantial potential for boosting oil recovery and enhancing economic efficiency.Despite this potential,discussion on gas injection coupling,especially in relation to microscopic mechanisms,remains relatively sparse.This study utilizes microscopic visualization experiments to investigate the mechanisms of residual oil mobilization under various IPC scenarios,complemented by mechanical analysis at different stages.The research quantitatively assesses the degree of microscopic oil recovery and the distribution of residual oil across different injection-production methods.Findings reveal that during the initial phase of continuous gas injection(CGI),the process closely mimics miscible displacement,gradually transitioning to immiscible displacement as CO_(2)extraction progresses.Compared to CGI,the asynchronous injection-production(AIP) method improved the microscopic oil recovery rate by 6.58%.This enhancement is mainly attributed to significant variations in the pressure field in the AIP method,which facilitate the mobilization of columnar and porous re sidual oil.Furthermo re,the synchronous cycle injection(SCI) method increased microscopic oil recovery by 13.77% and 7.19% compared to CGI and AIP,respectively.In the SCI method,membrane oil displays filame ntary and Karman vo rtex street flow patterns.The dissolved and expanded crude oil te nds to accumulate and grow at the oil-solid interface due to adhesive forces,thereby reducing migration resistance.The study findings provide a theoretical foundation for improving oil recovery in lowpermeability reservoirs. 展开更多
关键词 Low-permeability reservoirs Injection-production coupling microscopic experimental simulation technology CO_(2)-EOR Mechanical analysis
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Lipoxygenase inhibitory potential of secondary metabolites isolated from Pistacia integerrima:a comprehensive in vitro analysis integrating molecular docking,ADMET and DFT studies
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作者 Abdur Rauf Muhammad Umer Khan +6 位作者 Zuneera Akram Chaudhry Ahmed Shabbir Yahya Saleh Al-Awthan Omar Salem Bahattab Adil Abbas Hassan Mujawah Hassan A.Hemeg Marcello Iriti 《Traditional Medicine Research》 2025年第9期1-13,共13页
Background:Pistacia integerrima,a cornerstone of traditional medicine,is renowned for its therapeutic applications against various health conditions,including cancer and hepatitis.This study investigates the pharmacol... Background:Pistacia integerrima,a cornerstone of traditional medicine,is renowned for its therapeutic applications against various health conditions,including cancer and hepatitis.This study investigates the pharmacological potential of bioactive compounds derived from Pistacia integerrima in inhibiting 5-lipoxygenase(5-LOX),a key enzyme implicated in inflammation and cancer progression.The current study aimed to evaluate the lipoxygenase inhibitory activity of bioactive compounds from Pistacia integerrima and assess their potential for therapeutic development in the context of inflammation and cancer treatment.Methods:Three major compounds-spinacetin(1),patuletin(2),and pistagremic acid(3)-were isolated from Pistacia integerrima and analyzed for their lipoxygenase inhibitory activity.Biochemical assays and molecular docking studies were performed to assess their effectiveness in inhibiting 5-LOX.Results:All three compounds demonstrated significant inhibition of lipoxygenase activity.Spinacetin(1)and patuletin(2)exhibited the most potent inhibitory effects,with IC_(50)values of 40.34μM and 45.04μM,respectively.Molecular docking studies revealed that patuletin(2)had the highest binding affinity(−7.717 kcal/mol)against 5-LOX,followed by spinacetin(1)with a binding affinity of−6.074 kcal/mol.In-depth in silico analysis highlighted the drug-likeness of spinacetin(1)and its favorable toxicological profile,suggesting its suitability for therapeutic development.Conclusion:The study demonstrates that compounds from Pistacia integerrima,particularly spinacetin and patuletin,have significant lipoxygenase inhibitory activity,with spinacetin showing promise as a lead candidate for lipoxygenase-targeted therapies.The findings reinforce the therapeutic relevance of Pistacia integerrima and suggest that its bioactive compounds may serve as safer,plant-based alternatives to conventional anti-inflammatory and anticancer treatments. 展开更多
关键词 Pistacia integerrim PHYTOCHEMICALS 5-LOX in silico study molecular docking ADMET
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Author correction:Association between exposure to particulate matter during pregnancy and birthweight:A systematic review and a meta-analysis of birth cohort studies
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作者 Yinwen Ji Fei Song +3 位作者 Bo Xu Yining Zhu Chuncheng Lu Yankai Xia 《Journal of Biomedical Research》 2025年第5期538-548,I0048-I0066,共30页
The effect of prenatal exposure to ambient particulate matter(PM)on birth weight varies considerably across studies,and the findings remain inconclusive.In this study,we conducted a meta-analysis to assess the associa... The effect of prenatal exposure to ambient particulate matter(PM)on birth weight varies considerably across studies,and the findings remain inconclusive.In this study,we conducted a meta-analysis to assess the associations between exposure to PM_(2.5) and PM10 and birth weight.A total of 74 studies were identified through searches in Web of Science,PubMed,Embase,and Ovid Medline,as well as manual searches,up to October 2024.We found that for each 10μg/m^(3) increase in PM_(2.5),the risk of low birth weight(LBW)increased significantly during the entire pregnancy(odds ratio[OR]=2.41,95%confidence interval[CI]:1.99–2.91)and in all trimesters.Similarly,for every 10μg/m^(3) increase in PM10 concentration,the risk of LBW increased significantly during the entire pregnancy(OR=1.46,95%CI:1.16–1.84).Subgroup analysis by maternal age for PM_(2.5) showed that mothers aged 30 and above had a significantly higher risk of LBW(OR=3.69,95%CI:2.81–4.84),compared with those under 30.In conclusion,maternal exposure to PM_(2.5) and PM_(10) is associated with an increased risk of LBW across all trimesters.Additionally,mothers aged 30 and above are at a higher risk of LBW,compared with younger mothers.Further research is needed to clarify the biological mechanisms by which PM pollution may contribute to LBW. 展开更多
关键词 PM_(2.5) PM10 birth weight cohort study META-ANALYSIS
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