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An Improved Reinforcement Learning-Based 6G UAV Communication for Smart Cities
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作者 Vi Hoai Nam Chu Thi Minh Hue Dang Van Anh 《Computers, Materials & Continua》 2026年第1期2030-2044,共15页
Unmanned Aerial Vehicles(UAVs)have become integral components in smart city infrastructures,supporting applications such as emergency response,surveillance,and data collection.However,the high mobility and dynamic top... Unmanned Aerial Vehicles(UAVs)have become integral components in smart city infrastructures,supporting applications such as emergency response,surveillance,and data collection.However,the high mobility and dynamic topology of Flying Ad Hoc Networks(FANETs)present significant challenges for maintaining reliable,low-latency communication.Conventional geographic routing protocols often struggle in situations where link quality varies and mobility patterns are unpredictable.To overcome these limitations,this paper proposes an improved routing protocol based on reinforcement learning.This new approach integrates Q-learning with mechanisms that are both link-aware and mobility-aware.The proposed method optimizes the selection of relay nodes by using an adaptive reward function that takes into account energy consumption,delay,and link quality.Additionally,a Kalman filter is integrated to predict UAV mobility,improving the stability of communication links under dynamic network conditions.Simulation experiments were conducted using realistic scenarios,varying the number of UAVs to assess scalability.An analysis was conducted on key performance metrics,including the packet delivery ratio,end-to-end delay,and total energy consumption.The results demonstrate that the proposed approach significantly improves the packet delivery ratio by 12%–15%and reduces delay by up to 25.5%when compared to conventional GEO and QGEO protocols.However,this improvement comes at the cost of higher energy consumption due to additional computations and control overhead.Despite this trade-off,the proposed solution ensures reliable and efficient communication,making it well-suited for large-scale UAV networks operating in complex urban environments. 展开更多
关键词 UAV FANET smart cities reinforcement learning Q-LEARNING
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Intrusion Detection and Security Attacks Mitigation in Smart Cities with Integration of Human-Computer Interaction
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作者 Abeer Alnuaim 《Computers, Materials & Continua》 2026年第1期711-743,共33页
The rapid digitalization of urban infrastructure has made smart cities increasingly vulnerable to sophisticated cyber threats.In the evolving landscape of cybersecurity,the efficacy of Intrusion Detection Systems(IDS)... The rapid digitalization of urban infrastructure has made smart cities increasingly vulnerable to sophisticated cyber threats.In the evolving landscape of cybersecurity,the efficacy of Intrusion Detection Systems(IDS)is increasingly measured by technical performance,operational usability,and adaptability.This study introduces and rigorously evaluates a Human-Computer Interaction(HCI)-Integrated IDS with the utilization of Convolutional Neural Network(CNN),CNN-Long Short Term Memory(LSTM),and Random Forest(RF)against both a Baseline Machine Learning(ML)and a Traditional IDS model,through an extensive experimental framework encompassing many performance metrics,including detection latency,accuracy,alert prioritization,classification errors,system throughput,usability,ROC-AUC,precision-recall,confusion matrix analysis,and statistical accuracy measures.Our findings consistently demonstrate the superiority of the HCI-Integrated approach utilizing three major datasets(CICIDS 2017,KDD Cup 1999,and UNSW-NB15).Experimental results indicate that the HCI-Integrated model outperforms its counterparts,achieving an AUC-ROC of 0.99,a precision of 0.93,and a recall of 0.96,while maintaining the lowest false positive rate(0.03)and the fastest detection time(~1.5 s).These findings validate the efficacy of incorporating HCI to enhance anomaly detection capabilities,improve responsiveness,and reduce alert fatigue in critical smart city applications.It achieves markedly lower detection times,higher accuracy across all threat categories,reduced false positive and false negative rates,and enhanced system throughput under concurrent load conditions.The HCIIntegrated IDS excels in alert contextualization and prioritization,offering more actionable insights while minimizing analyst fatigue.Usability feedback underscores increased analyst confidence and operational clarity,reinforcing the importance of user-centered design.These results collectively position the HCI-Integrated IDS as a highly effective,scalable,and human-aligned solution for modern threat detection environments. 展开更多
关键词 Anomaly detection smart cities Internet of Things(IoT) HCI CNN LSTM random forest intelligent secure solutions
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Hybrid AI-IoT Framework with Digital Twin Integration for Predictive Urban Infrastructure Management in Smart Cities
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作者 Abdullah Alourani Mehtab Alam +2 位作者 Ashraf Ali Ihtiram Raza Khan Chandra Kanta Samal 《Computers, Materials & Continua》 2026年第1期462-493,共32页
The evolution of cities into digitally managed environments requires computational systems that can operate in real time while supporting predictive and adaptive infrastructure management.Earlier approaches have often... The evolution of cities into digitally managed environments requires computational systems that can operate in real time while supporting predictive and adaptive infrastructure management.Earlier approaches have often advanced one dimension—such as Internet of Things(IoT)-based data acquisition,Artificial Intelligence(AI)-driven analytics,or digital twin visualization—without fully integrating these strands into a single operational loop.As a result,many existing solutions encounter bottlenecks in responsiveness,interoperability,and scalability,while also leaving concerns about data privacy unresolved.This research introduces a hybrid AI–IoT–Digital Twin framework that combines continuous sensing,distributed intelligence,and simulation-based decision support.The design incorporates multi-source sensor data,lightweight edge inference through Convolutional Neural Networks(CNN)and Long ShortTerm Memory(LSTM)models,and federated learning enhanced with secure aggregation and differential privacy to maintain confidentiality.A digital twin layer extends these capabilities by simulating city assets such as traffic flows and water networks,generating what-if scenarios,and issuing actionable control signals.Complementary modules,including model compression and synchronization protocols,are embedded to ensure reliability in bandwidth-constrained and heterogeneous urban environments.The framework is validated in two urban domains:traffic management,where it adapts signal cycles based on real-time congestion patterns,and pipeline monitoring,where it anticipates leaks through pressure and vibration data.Experimental results show a 28%reduction in response time,a 35%decrease in maintenance costs,and a marked reduction in false positives relative to conventional baselines.The architecture also demonstrates stability across 50+edge devices under federated training and resilience to uneven node participation.The proposed system provides a scalable and privacy-aware foundation for predictive urban infrastructure management.By closing the loop between sensing,learning,and control,it reduces operator dependence,enhances resource efficiency,and supports transparent governance models for emerging smart cities. 展开更多
关键词 Smart cities digital twin AI-IOT framework predictive infrastructure management edge computing reinforcement learning optimization methods federated learning urban systems modeling smart governance
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The Evolution and Differentiation of Economic Convergence of Resource-based Cities in Northeast China 被引量:6
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作者 HUANG Yue FANG Yangang +1 位作者 GU Guofeng LIU Jisheng 《Chinese Geographical Science》 SCIE CSCD 2018年第3期495-504,共10页
A key target of the overall strategy implementation for regional development since the 18th Party Congress of China has involved taking measures to narrow regional disparities. This is because resource-based cities... A key target of the overall strategy implementation for regional development since the 18th Party Congress of China has involved taking measures to narrow regional disparities. This is because resource-based cities' economic development has fallen below general levels due to resource exhaustion and an unbalanced industrial structure, among other factors. Further, an economic gap has long existed between Northeast China's large number of resource-based cities and non-resource-based cities. This article comprehensively studies the economic convergence of Northeast China's resource-based cities and non-resource-based cities from 1996 to 2015 by using a dynamic panel to analyze not only the economic development of different industries and types of cities, but also the main factors that influence economic development. The empirical results demonstrate that economic convergence exists in both resource-based and non-resource-based cities, but the economic gap between them has clearly narrowed since the implementation of a strategy to revitalize the Northeast's old industrial base. Shrinking cities are the fastest to converge, as mature cities are slower and regenerating cities are the slowest; regarding industry structure, the secondary industry dominates the economy in mature and shrinking cities, and the tertiary industry in regenerating cities. The primary stimulus in resource-based cities' economic development involves upgrading the industrial structure and investing in human capital. As China faces a ‘new normal' economy, resource-based cities in Northeast China should restructure the economy and perfect their market system to avoid again widening the economic gap. 展开更多
关键词 economic convergence regional differences resource-based cities Northeast China
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Spatial-Temporal Differentiation of Sustainable Development in Cities and Counties of Hainan Province
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作者 ZHUANG Haiyan 《Journal of Landscape Research》 2018年第1期7-15,共9页
A total of 18 cities and counties in Hainan from 2012 to 2015 were selected as the basic research units to construct an index system for evaluating the ability of sustainable development that includes four guidelines ... A total of 18 cities and counties in Hainan from 2012 to 2015 were selected as the basic research units to construct an index system for evaluating the ability of sustainable development that includes four guidelines of economic development capacity, population development capacity, social support capacity, and resource utilization and environmental protection capacity. The improved entropy method was used to determine the weight, the Technique for Order of Preference by Similarity to Ideal Solution(TDPSIS) was used to calculate the capacity for sustainable development of the cities and counties and sort these cities and counties, and Arcgis10.2 was used to draw the provincewide distribution of the four guidelines. Thereupon, the author reached following conclusions: there was no big regional difference in the sustainable development capacity of cities and counties in Hainan, and they were basically in a general state of intermediate stage in the past four years; Haikou City and Sanya City, as the key cities, had a higher ability of sustainable development and had shown a remarkable capacity to drive the sustainable development of surrounding areas; according to the development level, the four guidelines were in the following order: resource utilization and environmental protection capacity, population development capacity, social support capacity, and economic development capacity. 展开更多
关键词 Sustainable development Index system EVALUATION cities and counties HAINAN
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NELL2,a novel osteoinductive factor,regulates osteoblast differentiation and bone homeostasis through fibronectin 1/integrin-mediated FAK/AKT signaling 被引量:1
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作者 Hairui Yuan Xinyu Wang +8 位作者 Shuanglin Du Mengyue Li Endong Zhu Jie Zhou Yuan Dong Shuang Wang Liying Shan Qian Liu Baoli Wang 《Bone Research》 2025年第4期895-909,共15页
Neural EGFL-like 2(NELL2)is a secreted protein known for its regulatory functions in the nervous and reproductive systems,yet its role in bone biology remains unexplored.In this study,we observed that NELL2 was dimini... Neural EGFL-like 2(NELL2)is a secreted protein known for its regulatory functions in the nervous and reproductive systems,yet its role in bone biology remains unexplored.In this study,we observed that NELL2 was diminished in the bone of aged and ovariectomized(OVX)mice,as well as in the serum of osteopenia and osteoporosis patients.In vitro loss-of-function and gain-offunction studies revealed that NELL2 facilitated osteoblast differentiation and impeded adipocyte differentiation from stromal progenitor cells.In vivo studies further demonstrated that the deletion of NELL2 in preosteoblasts resulted in decreased cancellous bone mass in mice.Mechanistically,NELL2 interacted with the FNI-type domain located at the C-terminus of Fibronectin 1(Fn1).Moreover,we found that NELL2 activated the focal adhesion kinase(FAK)/AKT signaling pathway through Fn1/integrinβ1(ITGB1),leading to the promotion of osteogenesis and the inhibition of adipogenesis.Notably,administration of NELL2-AAV was found to ameliorate bone loss in OVX mice.These findings underscore the significant role of NELL2 in osteoblast differentiation and bone homeostasis,suggesting its potential as a therapeutic target for managing osteoporosis. 展开更多
关键词 adipocyte differentiation osteoblast differentiation fak akt signaling FIBRONECTIN bone biology secreted protein stromal progenitor cells bone homeostasis
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Smart cities,smart systems:A comprehensive review of system dynamics model applications in urban studies in the big data era 被引量:2
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作者 Gift Fabolude Charles Knoble +1 位作者 Anvy Vu Danlin Yu 《Geography and Sustainability》 2025年第1期25-36,共12页
This paper addresses urban sustainability challenges amid global urbanization, emphasizing the need for innova tive approaches aligned with the Sustainable Development Goals. While traditional tools and linear models ... This paper addresses urban sustainability challenges amid global urbanization, emphasizing the need for innova tive approaches aligned with the Sustainable Development Goals. While traditional tools and linear models offer insights, they fall short in presenting a holistic view of complex urban challenges. System dynamics (SD) models that are often utilized to provide holistic, systematic understanding of a research subject, like the urban system, emerge as valuable tools, but data scarcity and theoretical inadequacy pose challenges. The research reviews relevant papers on recent SD model applications in urban sustainability since 2018, categorizing them based on nine key indicators. Among the reviewed papers, data limitations and model assumptions were identified as ma jor challenges in applying SD models to urban sustainability. This led to exploring the transformative potential of big data analytics, a rare approach in this field as identified by this study, to enhance SD models’ empirical foundation. Integrating big data could provide data-driven calibration, potentially improving predictive accuracy and reducing reliance on simplified assumptions. The paper concludes by advocating for new approaches that reduce assumptions and promote real-time applicable models, contributing to a comprehensive understanding of urban sustainability through the synergy of big data and SD models. 展开更多
关键词 Urban sustainability Smart cities System dynamics models Big data analytics Urban system complexity Data-driven urbanism
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Insight into leaching rare earth from ion-adsorption type rare earth ores with citric acid:Performance,kinetic analysis and differentiation leaching 被引量:1
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作者 Mengfei Zhao Zedong Teng +4 位作者 Xingyu Ma Xiaoliang Jiang Hualin Zhang Youming Yang Tinggang Li 《Journal of Rare Earths》 2025年第3期591-602,I0007,共13页
The rare earth elements(REEs)extraction by chemical leaching from ion-adsorption type rare earth ores(IAREO)has led to serious ecological and environmental risks.Conversely,demand for bioleaching is on the rise with t... The rare earth elements(REEs)extraction by chemical leaching from ion-adsorption type rare earth ores(IAREO)has led to serious ecological and environmental risks.Conversely,demand for bioleaching is on the rise with the advantage of being environmental-friendly.As one of the organic acids produced by biological metabolism,citric acid was used to leach REEs and explore the performance and process.The results demonstrate that citric acid exhibits higher leaching efficiency(96.00%)for REEs at a relatively low concentration of 0.01 mol/L compared with(NH_(4))_(2)SO_(4)(84.29%,0.1 mol/L)and MgSO_(4)(83.99%,0.1 mol/L).Citric acid shows a preference for leaching heavy rare earth elements,with 99%leaching efficiency in IAREO,which shows higher capacity than(NH_(4))_(2)SO_(4)and MgSO_(4)(as inorganic leaching agents).Kinetic analysis indicates that the leaching process of REEs with citric acid is controlled by both the internal diffusion kinetics and chemical reaction kinetics,which is different from inorganic leaching agents.Visual Minteq calculations confirm that RE-Citrate is the main constituent of the extract solution in the leaching process of the IAREO,thereby enhancing the leaching efficiency of REEs from the IAREO.It suggests that citric acid may be used as a promising organic leaching agent for the environmentalfriendly extraction of REEs from IAREO. 展开更多
关键词 Ion-adsorption type rare earth ores Rare earths Citric acid COMPLEXATION Organic acid Differential leaching
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Photobiomodulation:a novel approach to promote trans-differentiation of adipose-derived stem cells into neuronal-like cells
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作者 Daniella Da Silva Madeleen Jansen van Rensburg +1 位作者 Anine Crous Heidi Abrahamse 《Neural Regeneration Research》 SCIE CAS 2025年第2期598-608,共11页
Photobiomodulation,originally used red and near-infrared lasers,can alter cellular metabolism.It has been demonstrated that the visible spectrum at 451-540 nm does not necessarily increase cell proliferation,near-infr... Photobiomodulation,originally used red and near-infrared lasers,can alter cellular metabolism.It has been demonstrated that the visible spectrum at 451-540 nm does not necessarily increase cell proliferation,near-infrared light promotes adipose stem cell proliferation and affects adipose stem cell migration,which is necessary for the cells homing to the site of injury.In this in vitro study,we explored the potential of adipose-derived stem cells to differentiate into neurons for future translational regenerative treatments in neurodegenerative disorders and brain injuries.We investigated the effects of various biological and chemical inducers on trans-differentiation and evaluated the impact of photobiomodulation using 825 nm near-infrared and 525 nm green laser light at 5 J/cm2.As adipose-derived stem cells can be used in autologous grafting and photobiomodulation has been shown to have biostimulatory effects.Our findings reveal that adipose-derived stem cells can indeed trans-differentiate into neuronal cells when exposed to inducers,with pre-induced cells exhibiting higher rates of proliferation and trans-differentiation compared with the control group.Interestingly,green laser light stimulation led to notable morphological changes indicative of enhanced trans-differentiation,while near-infrared photobiomodulation notably increased the expression of neuronal markers.Through biochemical analysis and enzyme-linked immunosorbent assays,we observed marked improvements in viability,proliferation,membrane permeability,and mitochondrial membrane potential,as well as increased protein levels of neuron-specific enolase and ciliary neurotrophic factor.Overall,our results demonstrate the efficacy of photobiomodulation in enhancing the trans-differentiation ability of adipose-derived stem cells,offering promising prospects for their use in regenerative medicine for neurodegenerative disorders and brain injuries. 展开更多
关键词 differentiation inducers green photobiomodulation immortalized adipose-derived stem cell near-infrared photobiomodulation neurodegenerative disease NEUROGENESIS PHOTOBIOMODULATION TRANS-differentiation
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Magnolol inhibits appetite and causes visceral fat loss through Growth/differentiation factor-15(GDF-15)by activating transcription factor 4-CCAAT enhancer binding proteinγ-mediated endoplasmic reticulum stress responses 被引量:1
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作者 Keru Cheng Yanyun Zhou +4 位作者 Yilong Hao Shengyun Wu Nanping Wang Peng Zhang Yinfang Wang 《Chinese Journal of Natural Medicines》 2025年第3期334-345,共12页
Magnolol,a compound extracted from Magnolia officinalis,demonstrates potential efficacy in addressing metabolic dysfunction and cardiovascular diseases.Its biological activities encompass anti-inflammatory,antioxidant... Magnolol,a compound extracted from Magnolia officinalis,demonstrates potential efficacy in addressing metabolic dysfunction and cardiovascular diseases.Its biological activities encompass anti-inflammatory,antioxidant,anticoagulant,and anti-diabetic effects.Growth/differentiation factor-15(GDF-15),a member of the transforming growth factorβsuperfamily,is considered a potential therapeutic target for metabolic disorders.This study investigated the impact of magnolol on GDF-15 production and its underlying mechanism.The research examined the pharmacological effect of magnolol on GDF-15 expression in vitro and in vivo,and determined the involvement of endoplasmic reticulum(ER)stress signaling in this process.Luciferase reporter assays,chromatin immunoprecipitation,and in vitro DNA binding assays were employed to examine the regulation of GDF-15 by activating transcription factor 4(ATF4),CCAAT enhancer binding proteinγ(CEBPG),and CCCTC-binding factor(CTCF).The study also investigated the effect of magnolol and ATF4 on the activity of a putative enhancer located in the intron of the GDF-15 gene,as well as the influence of single nucleotide polymorphisms(SNPs)on magnolol and ATF4-induced transcription activity.Results demonstrated that magnolol triggers GDF-15 production in endothelial cells(ECs),hepatoma cell line G2(HepG2)and hepatoma cell line 3B(Hep3B)cell lines,and primary mouse hepatocytes.The cooperative binding of ATF4 and CEBPG upstream of the GDF-15 gene or the E1944285 enhancer located in the intron led to full-power transcription of the GDF-15 gene.SNP alleles were found to impact the magnolol and ATF4-induced transcription activity of GDF-15.In high-fat diet ApoE^(-/-)mice,administration of magnolol induced GDF-15 production and partially suppressed appetite through GDF-15.These findings suggest that magnolol regulates GDF-15 expression through priming of promoter and enhancer activity,indicating its potential as a drug for the treatment of metabolic disorders. 展开更多
关键词 MAGNOLOL Growth/differentiation factor-15 Activating transcription factor 4 CCAAT enhancer binding proteinγ ENHANCER Metabolic disorder
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基于ELITE Cities模型的贺州市低碳生态城市发展水平评价
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作者 韦芳宁 鄢世阳 +1 位作者 唐丽 黄楚欣 《中国资源综合利用》 2025年第8期64-66,共3页
随着我国城市化进程的加快,低碳生态城市成为可持续发展的核心目标。利用美国劳伦斯伯克利国家实验室开发的ELITE Cities模型,对广西壮族自治区贺州市的低碳生态发展水平进行评估。基于ELITE Cities模型的33项关键指标(共分为八大类),... 随着我国城市化进程的加快,低碳生态城市成为可持续发展的核心目标。利用美国劳伦斯伯克利国家实验室开发的ELITE Cities模型,对广西壮族自治区贺州市的低碳生态发展水平进行评估。基于ELITE Cities模型的33项关键指标(共分为八大类),分析贺州市在能源与气候、水资源、空气质量、移动性、土地使用、废弃物管理、经济及社会健康方面的表现,并与国内最佳实践进行比较。研究结果表明,贺州市整体表现良好,但在土地利用、医疗管理等方面仍有改进空间。 展开更多
关键词 低碳生态城市 ELITE cities模型 可持续发展 贺州市
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Nuclear farnesoid X receptor protects against bone loss by driving osteoblast differentiation through stabilizing RUNX2 被引量:2
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作者 Qi Dong Haoyuan Fu +14 位作者 Wenxiao Li Xinyu Ji Yingchao Yin Yiran Zhang Yanbo Zhu Guoqiang Li Huiyang Jia Heng Zhang Haofei Wang Jinglue Hu Ganggang Wang Zhihao Wu Yingze Zhang Sujuan Xu Zhiyong Hou 《Bone Research》 2025年第2期401-416,共16页
The delicate balance between bone formation by osteoblasts and bone resorption by osteoclasts maintains bone homeostasis.Nuclear receptors(NRs)are now understood to be crucial in bone physiology and pathology.However,... The delicate balance between bone formation by osteoblasts and bone resorption by osteoclasts maintains bone homeostasis.Nuclear receptors(NRs)are now understood to be crucial in bone physiology and pathology.However,the function of the Farnesoid X receptor(FXR),a member of the NR family,in regulating bone homeostasis remains incompletely understood.In this study,in vitro and in vivo models revealed delayed bone development and an osteoporosis phenotype in mice lacking FXR in bone marrow mesenchymal stem cells(BMSCs)and osteoblasts due to impaired osteoblast differentiation.Mechanistically,FXR could stabilize RUNX2 by inhibiting Thoc6-mediated ubiquitination,thereby promoting osteogenic activity in BMSCs.Moreover,activated FXR could directly bind to the Thoc6 promoter,suppressing its expression.The interaction between RUNX2 and Thoc6 was mediated by the Runt domain of RUNX2 and the WD repeat of Thoc6.Additionally,Obeticholic acid(OCA),an orally available FXR agonist,could ameliorate bone loss in an ovariectomy(OVX)-induced osteoporotic mouse model.Taken together,our findings suggest that FXR plays pivotal roles in osteoblast differentiation by regulating RUNX2 stability and that targeting FXR may be a promising therapeutic approach for osteoporosis. 展开更多
关键词 Farnesoid X receptor osteoporosis phenotype vitro vivo models farnesoid x receptor fxr bone homeostasis nuclear receptor osteoblast differentiation bone marrow mesenchymal stem cell
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Catalpol Promotes Differentiation of Neural Stem Cells into Oligodendrocyte via Caveolin-1-dependent Pathway in The 3D Microfluidic Chip
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作者 WANG Ya-Chen WANG Liang +1 位作者 SHEN Li-Ming LIU Jing 《生物化学与生物物理进展》 北大核心 2025年第11期2842-2853,共12页
Objective Cerebral palsy(CP)is a prevalent neurodevelopmental disorder acquired during the perinatal period,with periventricular white matter injury(PWMI)serving as its primary pathological hallmark.PWMI is characteri... Objective Cerebral palsy(CP)is a prevalent neurodevelopmental disorder acquired during the perinatal period,with periventricular white matter injury(PWMI)serving as its primary pathological hallmark.PWMI is characterized by the loss of oligodendrocytes(OLs)and the disintegration of myelin sheaths,leading to impaired neural connectivity and motor dysfunction.Neural stem cells(NSCs)represent a promising regenerative source for replenishing lost OLs;however,conventional twodimensional(2D)in vitro culture systems lack the three-dimensional(3D)physiological microenvironment.Microfluidic chip technology has emerged as a powerful tool to overcome this limitation by enabling precise spatial and temporal control over 3D microenvironmental conditions,including the establishment of stable concentration gradients of bioactive molecules.Catalpol,an iridoid glycoside derived from traditional medicinal plants,exhibits dual antioxidant and anti-apoptotic properties.Despite its therapeutic potential,the capacity of catalpol to drive NSC differentiation toward OLs under biomimetic 3D conditions,as well as the underlying molecular mechanisms,remains poorly understood.This study aims to develop a microfluidic-based 3D biomimetic platform to systematically investigate the concentration-dependent effects of catalpol on promoting NSCs-to-OLs differentiation and to elucidate the role of the caveolin-1(Cav-1)signaling pathway in this process.Methods We developed a novel multiplexed microfluidic device featuring parallel microchannels with integrated gradient generators capable of establishing and maintaining precise linear concentration gradients(0-3 g/L catalpol)across 3D NSCs cultures.This platform facilitated the continuous perfusion culture of NSC-derived 3D spheroids,mimicking the dynamic in vivo microenvironment.Real-time cell viability was assessed using Calcein-AM/propidium iodide(PI)dual staining,with fluorescence imaging quantifying live/dead cell ratios.Oligodendrocyte differentiation was evaluated through quantitative reverse transcription polymerase chain reaction(qRT-PCR)for MBP and SOX10 gene expression,complemented by immunofluorescence staining to visualize corresponding protein changes.To dissect the molecular mechanism,the Cav-1-specific pharmacological inhibitor methyl‑β‑cyclodextrin(MCD)was employed to perturb the pathway,and its effects on differentiation markers were analyzed.Results Catalpol demonstrated excellent biocompatibility,with cell viability exceeding 96%across the entire tested concentration range(0-3 g/L),confirming its non-cytotoxic nature.At the optimal concentration of 0-3 g/L,catalpol significantly upregulated both MBP and SOX10 expression(P<0.05,P<0.01),indicating robust promotion of oligodendroglial differentiation.Intriguingly,Cav-1 mRNA expression was progressively downregulated during NSC differentiation into OLs.Further inhibition of Cav-1 with MCD further enhanced this effect,leading to a statistically significant increase in OL-specific gene expression(P<0.05,P<0.01),suggesting Cav-1 acts as a negative regulator of OLs differentiation.Conclusion This study established an integrated microfluidic gradient chip-3D NSC spheroid culture system,which combines the advantages of precise chemical gradient control with physiologically relevant 3D cell culture.The findings demonstrate that 3 g/L catalpol effectively suppresses Cav-1 signaling to drive NSC differentiation into functional OLs.This work not only provides novel insights into the Cav-1-dependent mechanisms of myelination but also delivers a scalable technological platform for future research on remyelination therapies,with potential applications in cerebral palsy and other white matter disorders.The platform’s modular design permits adaptation for screening other neurogenic compounds or investigating additional signaling pathways involved in OLs maturation. 展开更多
关键词 CATALPOL neural stem cells OLIGODENDROCYTES differentiation CAVEOLIN-1 microfluidic chip
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Products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball
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作者 ZHANG Chao QIN Yuehai 《中山大学学报(自然科学版)(中英文)》 北大核心 2025年第2期160-169,共10页
The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic fu... The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic functions in the unit ball by radial derivative.Then we extend the Sharma's results. 展开更多
关键词 composition operator multiplication operator differentiation operator weighted Bergman space
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Rurbanization: Effects and Challenges on Small and Medium-Sized Cities
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作者 Rebecca Oberreiter 《Management Studies》 2025年第2期88-95,共8页
Rurbanization,characterized by the integration of rural and urban attributes,holds significant implications for the development and marketing of small and medium-sized cities.This study investigates the effects of rur... Rurbanization,characterized by the integration of rural and urban attributes,holds significant implications for the development and marketing of small and medium-sized cities.This study investigates the effects of rurbanization on city marketing strategies and urban growth through a comprehensive review of recent literature.Key factors influencing rurbanization are identified,along with their impacts on city marketing practices.The findings indicate that rurbanization enhances city branding,attracts new residents and businesses,and promotes sustainable urban development.However,the phenomenon also presents challenges,including infrastructural strain and socio-cultural integration issues.Furthermore,rurbanization influences the socio-economic dynamics of cities,resulting in both opportunities and inequalities that require careful management.The study concludes with actionable recommendations for leveraging rurbanization to achieve positive city marketing outcomes while addressing associated challenges.This research aims to deepen the understanding of rurbanization and provide practical insights for policymakers,urban planners,and marketers in small and medium-sized cities,enabling them to optimize their growth strategies effectively. 展开更多
关键词 rurbanization city marketing small and medium-sized cities urban development city branding sustainable development
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A Review on Integration of IoT as an Approach for Energy Saving in Smart Sustainable Cities
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作者 Mohd Addad Shehadeh Al-Taani 《Journal of Environmental Science and Engineering(A)》 CAS 2025年第1期60-71,共12页
Rapid urbanization has been happening around the world,leading to many challenges and difficulties in infrastructure,communication network,transportation,environmental and organizational problems.Proper and responsibl... Rapid urbanization has been happening around the world,leading to many challenges and difficulties in infrastructure,communication network,transportation,environmental and organizational problems.Proper and responsible management of urban resources plays a significant role in sustainable development.Smart sustainable cities use ICTs(Information and Communication Technologies)to improve quality of life,efficiency of urban operation and services.The latest advancement in communication,technology,data management,and IoT(Internet of Things)provide a tremendous role for practical implementations and adoption of devices and entities.Smart sustainable cities can be intellectualized as an innovative approach of controlling urban resources and valuable components based on the latest advancement in ICT.Our study focuses on reviewing and discussing the literature that states the vital components of IoT associated with smart sustainable cities in general and specifically with green energy. 展开更多
关键词 IOT devices and sensors smart sustainable cities and green energy.
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Exploration of constructing a relatively comprehensive syndrome differentiation and treatment system based on dialectical materialism principles
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作者 ZHANG Gedi WEN Xiaoli +2 位作者 TAO Tianming YAN Ziyou LIU Hongning 《Journal of Traditional Chinese Medicine》 2025年第5期1164-1168,共5页
It is well known that Traditional Chinese Medicine(TCM)has two outstanding academic characteristics:the holistic concept comes from Huang Di Nei Jing,and the syndrome differentiation and treatment comes from Shang Han... It is well known that Traditional Chinese Medicine(TCM)has two outstanding academic characteristics:the holistic concept comes from Huang Di Nei Jing,and the syndrome differentiation and treatment comes from Shang Han Lun.These two characteristics denote the two major academic systems of TCM:one is the medical system of Huang Di Nei Jing,also named syndrome differentiation and treatment system of Zang-Fu organs and meridians,focuses on theoretical exploration,which highlights functional connection and emphasizes philosophical thinking.The treatment in this system is based on physiological functions by taking Zang-Fu organs as the main body,Qi,blood,essence,and body fluid as the auxiliary body,and the meridians and collaterals as the connection channels.The other is the syndrome differentiation and treatment system of the six meridians,which emphasizes clinical practice.It encompasses the idea that the six meridians govern various diseases,emphasizes the disease sites and divisional treatment,and pays attention to the precision and appropriateness of prescription-syndrome differentiation.These two academic systems,with mutual influences and relations,are both the essence and pearl of TCM,nevertheless,there are obvious differences between the two in clinical application,so they should be distinguished.This paper will elaborate on the connection and difference between them,and how to organically combine the two systems for better application in clinical practice of TCM. 展开更多
关键词 syndrome differentiation six-meridians syndrome differentiation Zang-Fu viscera syndrome differentiation meridians dialectical materialism review
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Maintaining moderate levels of hypochlorous acid promotes neural stem cell proliferation and differentiation in the recovery phase of stroke
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作者 Lin-Yan Huang Yi-De Zhang +9 位作者 Jie Chen Hai-Di Fan Wan Wang Bin Wang Ju-Yun Ma Peng-Peng Li Hai-Wei Pu Xin-Yian Guo Jian-Gang Shen Su-Hua Qi 《Neural Regeneration Research》 SCIE CAS 2025年第3期845-857,共13页
It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late stroke.Indeed,previous studies have shown that excessive increases ... It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late stroke.Indeed,previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain tissue.Our previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke,but its specific role and mechanism are currently unclear.To simulate stroke in vivo,a middle cerebral artery occlusion rat model was established,with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic stroke.We found that in the early stage(within 24 hours)of ischemic stroke,neutrophils produced a large amount of hypochlorous acid,while in the recovery phase(10 days after stroke),microglia were activated and produced a small amount of hypochlorous acid.Further,in acute stroke in rats,hypochlorous acid production was prevented using a hypochlorous acid scavenger,taurine,or myeloperoxidase inhibitor,4-aminobenzoic acid hydrazide.Our results showed that high levels of hypochlorous acid(200μM)induced neuronal apoptosis after oxygen/glucose deprivation/reoxygenation.However,in the recovery phase of the middle cerebral artery occlusion model,a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and astrocytes.This suggests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion injury.Lower levels of hypochlorous acid(5 and 100μM)promoted nuclear translocation ofβ-catenin.By transfection of single-site mutation plasmids,we found that hypochlorous acid induced chlorination of theβ-catenin tyrosine 30 residue,which promoted nuclear translocation.Altogether,our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function. 展开更多
关键词 cell differentiation cerebral ischemia/reperfusion injury CHLORINATION hypochlorous acid MICROGLIA neural stem cell NEUROGENESIS nuclear translocation stroke β-catenin
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Smart Cities,Digital Citizenship
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作者 ZHOU LIN 《China Today》 2025年第8期28-31,共4页
Beijing defines a new model for digital-friendly cities where technology meets people’s needs and global cooperation drives inclusivity.THE 6,000-square-meter Beijing FUN Digital Complex,a vibrant pedestrian street i... Beijing defines a new model for digital-friendly cities where technology meets people’s needs and global cooperation drives inclusivity.THE 6,000-square-meter Beijing FUN Digital Complex,a vibrant pedestrian street in the historic Qianmen area of central Beijing,was bustling with visitors during the 2025 Beijing Digital Economy Experience Week,held from June 27 to July 5.Some climbed into a full-size C919 flight simulator,while others put on a domestically-made 8K VR headset to test a real-time voice-interaction model,immersing themselves in a dazzling virtual world. 展开更多
关键词 technology digital citizenship digital friendly cities smart cities peoples needs k vr headset global cooperation BEIJING
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Impact of Built Environment on Urban Vitality in Shrinking Cities:Moderating Effect of Housing Vacancy
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作者 FU Hui ZHOU Guolei +3 位作者 SUN Hongri JIN Yu WU Hanchun LIU Yanjun 《Chinese Geographical Science》 2025年第6期1428-1443,共16页
Urban vitality is one of the key indicators of sustainable urban development and an important factor for shrinking cities to achieve internal optimization.The relationship between the built environment and urban vital... Urban vitality is one of the key indicators of sustainable urban development and an important factor for shrinking cities to achieve internal optimization.The relationship between the built environment and urban vitality has been extensively discussed.However,the moderating effect of housing vacancy on the built environment’s effect on urban vitality in shrinking cities has not been explored in detail.This paper selected Yichun District in Yichun City of Heilongjiang Province,a typical shrinking city in Northeast China,as the study area,focusing on the effect of the built environment on urban vitality in shrinking cities based on residential and commercial electricity consumption data for 2013 and 2018.Moreover,this study also explored the moderating mechanisms of residential and commercial housing vacancies on the built environment’s effect on urban vitality.The results demonstrate that the spatial pattern of urban vitality in the Yichun District is‘high in the center and low in the periphery’.Population density,building age,road density,and catering facilities are recognized as the main built environment factors affecting the vitality of shrinking cities.Residential and commercial housing vacancies have a significant moderating effect on the built environment’s effect on urban vitality.Residential housing vacancies enhance the positive effect of road density and the negative effect of greening rate.In addition,commercial housing vacancies suppress the positive effect of building density and enhance the positive effect of accessibility to urban service facilities.The study indicates that built environment factors exhibit heterogeneous effects on vitality in the context of urban shrinkage,as moderated by housing vacancies.Targeted regulation of built environment factors is of practical significance in realizing the internal development and vitality enhancement of shrinking cities. 展开更多
关键词 housing vacancy urban vitality built environment shrinking cities Yichun District Yichun City China
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