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面向对象程序设计课程教学改革路径探索
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作者 汤显 刘翔 石蕴玉 《计算机教育》 2026年第2期159-164,共6页
针对传统编程课程中存在的统一化教学局限、知识体系断裂、认知负荷失衡与能力评估错位等核心问题,构建“分层—重构—调控—评价”四位一体的教学改革框架,通过动态分层教学模式实现差异化培养,采用案例贯穿式教学法重构知识链条,设计... 针对传统编程课程中存在的统一化教学局限、知识体系断裂、认知负荷失衡与能力评估错位等核心问题,构建“分层—重构—调控—评价”四位一体的教学改革框架,通过动态分层教学模式实现差异化培养,采用案例贯穿式教学法重构知识链条,设计模块化认知单元调控学习负荷,建立教考分离的多元评价体系。研究为破解编程教育中“高分低能”困境提供了理论范式与实践路径,推动编程教育向工程思维培养转型。 展开更多
关键词 认知异质性 动态分层 教考分离 课程改革 程序设计
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建材产品碳足迹核算要点分析--以水泥产品碳足迹核算为例
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作者 郭星妤 卓俊好 +8 位作者 刘璐 伍林莉 潘伟东 郑光东 谢维 向柳 王兴伟 高玮 陈欣 《中国建材科技》 2026年第1期101-108,共8页
随着中国“双碳”战略的深入推进,建材行业作为碳排放量较大的产业,其碳足迹核算工作成为实现低碳转型的基础和关键。本文以水泥产品为具体研究对象,分析了建材产品碳足迹核算的要点与方法,系统阐述了生命周期评估理论在水泥产品中的应... 随着中国“双碳”战略的深入推进,建材行业作为碳排放量较大的产业,其碳足迹核算工作成为实现低碳转型的基础和关键。本文以水泥产品为具体研究对象,分析了建材产品碳足迹核算的要点与方法,系统阐述了生命周期评估理论在水泥产品中的应用框架,探讨了系统边界划定、数据采集处理、核算方法选择等关键环节,并对水泥产品碳足迹核算当前面临的问题,提出优化建议,以期为建材行业尤其是水泥企业开展碳足迹核算与管理工作提供参考,推动行业绿色低碳高质量发展。 展开更多
关键词 建材 水泥 碳足迹 生命周期评价 碳排放 低碳转型
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LP-YOLO:Enhanced Smoke and Fire Detection via Self-Attention and Feature Pyramid Integration
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作者 Qing Long Bing Yi +2 位作者 Haiqiao liu Zhiling Peng xiang liu 《Computers, Materials & Continua》 2026年第3期1490-1509,共20页
Accurate detection of smoke and fire sources is critical for early fire warning and environmental monitoring.However,conventional detection approaches are highly susceptible to noise,illumination variations,and comple... Accurate detection of smoke and fire sources is critical for early fire warning and environmental monitoring.However,conventional detection approaches are highly susceptible to noise,illumination variations,and complex environmental conditions,which often reduce detection accuracy and real-time performance.To address these limitations,we propose Lightweight and Precise YOLO(LP-YOLO),a high-precision detection framework that integrates a self-attention mechanism with a feature pyramid,built upon YOLOv8.First,to overcome the restricted receptive field and parameter redundancy of conventional Convolutional Neural Networks(CNNs),we design an enhanced backbone based on Wavelet Convolutions(WTConv),which expands the receptive field through multifrequency convolutional processing.Second,a Bidirectional Feature Pyramid Network(BiFPN)is employed to achieve bidirectional feature fusion,enhancing the representation of smoke features across scales.Third,to mitigate the challenge of ambiguous object boundaries,we introduce the Frequency-aware Feature Fusion(FreqFusion)module,in which the Adaptive Low-Pass Filter(ALPF)reduces intra-class inconsistencies,the offset generator refines boundary localization,and the Adaptive High-Pass Filter(AHPF)recovers high-frequency details lost during down-sampling.Experimental evaluations demonstrate that LP-YOLO significantly outperforms the baseline YOLOv8,achieving an improvement of 9.3%in mAP@50 and 9.2%in F1-score.Moreover,the model is 56.6%and 32.4%smaller than YOLOv7-tiny and EfficientDet,respectively,while maintaining real-time inference speed at 238 frames per second(FPS).Validation on multiple benchmark datasets,including D-Fire,FIRESENSE,and BoWFire,further confirms its robustness and generalization ability,with detection accuracy consistently exceeding 82%.These results highlight the potential of LP-YOLO as a practical solution with high accuracy,robustness,and real-time performance for smoke and fire source detection. 展开更多
关键词 Deep learning smoke detection feature pyramid boundary refinement
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Comparative proteomic analysis of plasma exosomes reveals the functional contribution of N-acetyl-alpha-glucosaminidase to Parkinson’s disease 被引量:1
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作者 Yuan Zhao Yidan Zhang +6 位作者 Xin liu Jian Zhang Ya Gao Shuyue Li Cui Chang xiang liu Guofeng Yang 《Neural Regeneration Research》 SCIE CAS 2025年第10期2998-3012,共15页
Parkinson’s disease is the second most common progressive neurodegenerative disorder,and few reliable biomarkers are available to track disease progression.The proteins,DNA,mRNA,and lipids carried by exosomes reflect... Parkinson’s disease is the second most common progressive neurodegenerative disorder,and few reliable biomarkers are available to track disease progression.The proteins,DNA,mRNA,and lipids carried by exosomes reflect intracellular changes,and thus can serve as biomarkers for a variety of conditions.In this study,we investigated alterations in the protein content of plasma exosomes derived from patients with Parkinson’s disease and the potential therapeutic roles of these proteins in Parkinson’s disease.Using a tandem mass tag-based quantitative proteomics approach,we characterized the proteomes of plasma exosomes derived from individual patients,identified exosomal protein signatures specific to patients with Parkinson’s disease,and identified N-acetyl-alpha-glucosaminidase as a differentially expressed protein.N-acetyl-alpha-glucosaminidase expression levels in exosomes from the plasma of patients and healthy controls were validated by enzyme-linked immunosorbent assay and western blot.The results demonstrated that the exosomal N-acetyl-alpha-glucosaminidase concentration was not only lower in Parkinson’s disease,but also decreased with increasing Hoehn-Yahr stage,suggesting that N-acetyl-alpha-glucosaminidase could be used to rapidly evaluate Parkinson’s disease severity.Furthermore,western blot and immunohistochemistry analysis showed that N-acetyl-alpha-glucosaminidase levels were markedly reduced both in cells treated with 1-methyl-4-phenylpyridinium and cells overexpressingα-synuclein compared with control cells.Additionally,N-acetyl-alpha-glucosaminidase overexpression significantly increased cell viability and inhibitedα-synuclein expression in 1-methyl-4-phenylpyridinium-treated cells.Taken together,our findings demonstrate for the first time that exosomal N-acetyl-alpha-glucosaminidase may serve as a biomarker for Parkinson’s disease diagnosis,and that N-acetyl-alpha-glucosaminidase may reduceα-synuclein expression and 1-methyl-4-phenylpyridinium-induced neurotoxicity,thus providing a new therapeutic target for Parkinson’s disease. 展开更多
关键词 biomarker diagnosis EXOSOMES N-acetyl-alpha-glucosaminidase Parkinson’s disease proteomic α-synuclein
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氮掺杂显著提升BiOBr光催化还原CO_(2)性能研究 被引量:1
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作者 宋相海 刘晓颖 +6 位作者 任智祥 刘想 汪梅 吴元锋 周伟强 朱志 霍鹏伟 《物理化学学报》 北大核心 2025年第6期78-90,共13页
光催化还原二氧化碳(CO_(2))是一种有望解决全球能源与环境问题的方法。寻找在CO_(2)转化方面具有高活性和高选择性的催化剂受到了广泛关注。本研究采用简单的水热法合成了超薄氮掺杂的BiOBr纳米片。系统的实验结果表明,氮掺杂降低了Bi... 光催化还原二氧化碳(CO_(2))是一种有望解决全球能源与环境问题的方法。寻找在CO_(2)转化方面具有高活性和高选择性的催化剂受到了广泛关注。本研究采用简单的水热法合成了超薄氮掺杂的BiOBr纳米片。系统的实验结果表明,氮掺杂降低了BiOBr纳米片的厚度并增加了其比表面积。此外,光生载流子迁移效率和CO_(2)吸附能力显著增强,从而提高了光催化还原CO_(2)性能。实验结果表明,2N-BiOBr具有最佳的催化性能,反应在水中进行时,CO的生成速率为18.28μmol·g^(-1)·h^(-1),是纯BiOBr的三倍,且CO选择性接近100%。利用原位FTIR和DFT模拟研究了潜在的光催化机制。机理研究表明,氮原子取代氧原子作为吸附中心时,相比于O—H,BiOBr对CO_(2)的吸附选择性显著增强,并促进了关键反应中间体的形成。本研究为高效光催化材料的制备与开发提供了新的视角,并为光催化技术在能源与环境科学中的应用提供了理论支持。 展开更多
关键词 N掺杂 CO_(2)吸附 超薄BiOBr 光催化剂 CO_(2)还原
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In-situ observation and analysis of high temperature behavior of carbides in GCr15 bearing steel by confocal laser scanning microscopy 被引量:2
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作者 Jun Ren Yue Teng +4 位作者 xiang liu Xi Xu Hui-gai Li Ke Han Qi-jie Zhai 《Journal of Iron and Steel Research International》 2025年第2期409-417,共9页
The high-temperature dissolution behavior of primary carbides in samples taken from GCr15 continuous-casting bloom was observed in-situ by confocal laser scanning microscopy.Equations were fitted to the dissolution ki... The high-temperature dissolution behavior of primary carbides in samples taken from GCr15 continuous-casting bloom was observed in-situ by confocal laser scanning microscopy.Equations were fitted to the dissolution kinetics of primary carbides during either heating or soaking.Dissolution of carbides proceeded in three stages(fast→slow→faster)as either temperature or holding time was increased.During the heating process and during the first and third stages of the soaking process,the original size of the carbides determined the steepness of the slope,but during the middle(“slow”)stage of the soaking process,the slope remained zero.The initial size of the carbides varied greatly,but their final dissolution temperature fell within the narrow range of 1210-1235℃,and the holding time remained within 50 min.Fractal analysis was used to study the morphological characteristics of small and medium-sized carbides during the dissolution process.According to changes in the fractal dimension before and after soaking,the carbides tended to evolve towards a more regular morphology. 展开更多
关键词 Bearing steel High-temperature confocal laser scanning microscope In-situ observation Primary carbide Fractal analysis
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Risks and governance of heavy metals in European soil applied phosphate fertilizers 被引量:1
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作者 Lian-kai Zhang xiang liu +5 位作者 Ya-jie Sun Bernd G.Lottermoser Roland Bol Heike Windmann Silvia H.Haneklaus Ewald Schnug 《China Geology》 2025年第3期560-572,共13页
Phosphorus(P)poses a global challenge to the environment and human health due to its natural association with heavy metals.Sustainable use of P is crucial to ensure food security for future generations.An analysis of ... Phosphorus(P)poses a global challenge to the environment and human health due to its natural association with heavy metals.Sustainable use of P is crucial to ensure food security for future generations.An analysis of the 150 phosphate fertilizers stored at the Institute for Crop and Soil Science in Germany has been conducted,supplemented by previously published data.The elements Cd,Bi,U,Cr,Zn,Tl,As,B,Sb,Ni,and Se are found in higher concentrations in sedimentary derived phosphates compared to igneous derived phosphates.Mineral fertilizers contain more than ten times the amount of U,Cd,B,and As compared to farmyard manure.Principal component analyses(PCA)indicate that U,Cd,Be,and Cr are primarily present in sedimentary derived phosphates and their concentrations are 2 to 10 times higher than those in igneous derived phosphates.Regarding heavy metal contamination,over 1000 potential combinations were identified;36% of these were significant but weak(>0.1).It is estimated that approximately 707 t of uranium enter farmland annually through the application of mineral phosphate fertilizers in European countries.This contribution addresses environmental issues related to the utilization of rock phosphate as well as alternative production methods for cleaner and safer phosphate fertilizers while presenting a roadmap with measures for mitigation. 展开更多
关键词 Phosphorus fertilizer Heavy metals U-Cd-Cr-Tl SOIL Mitigation Sustainable measures EUROPE Sustainable Development Goals(SDG 3) Environmental geological survey engineering
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Role of urea in the retention of DON in soil by clay minerals:Analysis based upon molecular weight 被引量:1
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作者 Leyun Wang Miao Li xiang liu 《Journal of Environmental Sciences》 2025年第4期362-372,共11页
As a widely used fertilizer,urea significantly promotes the leaching of dissolved organic nitrogen(DON)in soils and aggravates nitrogen contamination in groundwater.Clayminerals are considered the most important facto... As a widely used fertilizer,urea significantly promotes the leaching of dissolved organic nitrogen(DON)in soils and aggravates nitrogen contamination in groundwater.Clayminerals are considered the most important factor in retaining DON.However,the effect of urea on the retention of DON with different molecular weights by clay minerals is unknown.In this study,the retention of both low-molecular weight DON(LMWD)and high-molecular weight DON(HMWD)by clay minerals in the presence of urea was investigated.For this purpose,batch adsorption and soil column leaching experiments,characterization analysis(Fourier transform infrared spectroscopy X-ray diffraction,and X-ray photoelectron spectroscopy),and molecular dynamics simulations were carried out.Urea had a positive effect on the adsorption of LMWD,whereas a competitive effect existed for the adsorption of HMWD.The dominant interactions among DON,urea,and clay minerals included H-bonding,ligand exchange,and cation exchange.The urea was preferentially adsorbed on clay minerals and formed a complex,which provided more adsorption sites to LMWD and only a few to HMWD.The presence of urea increased the retention of LMWD and decreased the retention of HMWD in clay minerals.The retention capacity of LMWD increased by 6.9%–12.8%,while that of HMWD decreased by 6.7%–53.1%.These findings suggest that LMWD tended to be trapped in soils,while HMWD was prone to be leached into groundwater,which can be used to evaluate the leaching of DON from soil to groundwater. 展开更多
关键词 UREA Dissolved organic nitrogen Clay mineral Molecular dynamics RETENTION
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Synergistic effect of oxygen-deficient Ni_(3)V_(2)O_(8)@carbon nanotubes-modified separator for advanced lithium-sulfur batteries 被引量:1
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作者 Zheng-Dao Pan Zhou-Lu Wang +2 位作者 Xing-You Rao xiang liu Yi Zhang 《Rare Metals》 2025年第3期1632-1648,共17页
Lithium-sulfur batteries(LSBs)have attracted widespread attention due to their high theoretical energy density.However,the dissolution of long-chain polysulfides into the electrolyte(the“shuttle effect”)leads to rap... Lithium-sulfur batteries(LSBs)have attracted widespread attention due to their high theoretical energy density.However,the dissolution of long-chain polysulfides into the electrolyte(the“shuttle effect”)leads to rapid capacity decay.Therefore,finding suitable materials to mitigate the shuttle effect of polysulfides is crucial for enhancing the electrochemical performance of lithium-sulfur batteries.In this study,LSBs’separator is modified with Ni_(3)V_(2)O_(8)nanoparticles@carboxylated carbon nanotubes(Ni_(3)V_(2)O_(8)@CNTs)composite.There are abundant oxygen vacancies in Ni_(3)V_(2)O_(8)@CNTs composite which plays a synergistic effect on shuttle effect.The Ni_(3)V_(2)O_(8)can tightly anchor soluble polysulfides through oxygen vacancies,while the CNTs not only facilitate the transport of ions and electrons but also weaken the migration of polysulfides,limiting shuttle effect.As a result,the cycling stability of LSBs using Ni_(3)V_(2)O_(8)@CNTs-modified separator has been significantly improved(with a capacity decay rate of only 0.0334%after 1500 cycles at 4.0C).This study proposes a strategy to design modified separator for high-performance LSBs. 展开更多
关键词 Lithium-sulfur batteries SEPARATOR Ni_(3)V_(2)O_(8) Oxygen vacancy Shuttle effect
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Piezoelectric Actuator Placement Optimization and Active Vibration Control of a Membrane Structure 被引量:3
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作者 xiang liu Guoping Cai +1 位作者 Fujun Peng Hua Zhang 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2018年第1期66-79,共14页
The placement optimization of piezoelectric actuators and active vibration control of a membrane structure are studied in this paper. The classical linear quadratic regulator con- trollers are designed to suppress the... The placement optimization of piezoelectric actuators and active vibration control of a membrane structure are studied in this paper. The classical linear quadratic regulator con- trollers are designed to suppress the unwanted vibration. Simulation results indicate that the optimal locations of piezoelectric actuators are affected deeply by the additional mass and stiff- ness of actuators, the computational efficiency of particle swarm optimizer is higher than that of genetic algorithm for this particular problem, and the control performance of optimally placed actuators is better than that of non-optimally placed actuators. 展开更多
关键词 MEMBRANE Smart structure Vibration control
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Adaptive scale model reconstruction for radio synthesis imaging 被引量:2
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作者 Li Zhang Li-Gong Mi +6 位作者 Long Xu Ming Zhang Dan-Yang Li xiang liu Feng Wang Yi-Fan Xiao Zhong-Zu Wu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第3期117-127,共11页
A sky model from CLEAN deconvolution is a particularly effective high dynamic range reconstruction in radio astronomy,which can effectively model the sky and remove the sidelobes of the point spread function(PSF)cause... A sky model from CLEAN deconvolution is a particularly effective high dynamic range reconstruction in radio astronomy,which can effectively model the sky and remove the sidelobes of the point spread function(PSF)caused by incomplete sampling in the spatial frequency domain.Compared to scale-free and multi-scale sky models,adaptive-scale sky modeling,which can model both compact and diffuse features,has been proven to have better sky modeling capabilities in narrowband simulated data,especially for large-scale features in high-sensitivity observations which are exactly one of the challenges of data processing for the Square Kilometre Array(SKA).However,adaptive scale CLEAN algorithms have not been verified by real observation data and allow negative components in the model.In this paper,we propose an adaptive scale model algorithm with non-negative constraint and wideband imaging capacities,and it is applied to simulated SKA data and real observation data from the Karl G.Jansky Very Large Array(JVLA),an SKA precursor.Experiments show that the new algorithm can reconstruct more physical models with rich details.This work is a step forward for future SKA image reconstruction and developing SKA imaging pipelines. 展开更多
关键词 methods:data analysis techniques:image processing techniques:interferometric
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结直肠癌术后辅助卡培他滨为基础化疗方案的临床疗效及相关药物基因组学分析 被引量:6
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作者 刘世举 张慧俭 +4 位作者 王金榜 杨会举 张新春 刘翔 刘佃温 《中国肿瘤临床》 CAS CSCD 北大核心 2018年第17期889-893,共5页
目的:本研究旨在探讨结直肠癌(colorectal cancer,CRC)术后辅助卡培他滨为基础化疗方案的疗效及相关药物基因组学分析。方法:回顾性分析2010年1月至2017年6月河南中医药大学第三附属医院收治术后接受辅助化疗的CRC患者215例。收集外周... 目的:本研究旨在探讨结直肠癌(colorectal cancer,CRC)术后辅助卡培他滨为基础化疗方案的疗效及相关药物基因组学分析。方法:回顾性分析2010年1月至2017年6月河南中医药大学第三附属医院收治术后接受辅助化疗的CRC患者215例。收集外周血提取DNA用来进行胞苷脱氨酶(cytidine deaminase,CDD)多态性位点基因分型。另外,收集85例患者的化疗前外周血单核细胞(peripheral blood mononuclear cell,PBMC)提取RNA对CDD的m RNA表达水平进行测定。结果:215例患者具有良好的疗效。药物基因组学分析方面,发现CDD基因启动子区域的多态性位点-451C>A和疗效相关,该位点GA/AA和GG基因型患者的3年无疾病生存率(disease-free survival,DFS)分别为81.03%和62.42%,差异具有统计学意义(P=0.002)。两种基因型患者的5年总生存率(overall survival,OS)分别为72.41%和53.50%,差异具有统计学意义(P=0.016)。在85例患者外周血单核细胞的mRNA表达分析中发现,携带A等位基因的患者相对于GG型患者,外周血单核细胞中CDD的mRNA表达明显较高,差异具有统计学意义(P<0.001)。结论:卡培他滨为基础的化疗方案具有良好的治疗效果。CDD基因-451C>A位点可能通过影响该基因m RNA的表达使CRC患者从卡培他滨的治疗当中获益。 展开更多
关键词 结直肠癌 胞苷脱氨酶 多态性 疗效
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XRD对ZnO薄膜生长条件和退火工艺的优化 被引量:3
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作者 王金忠 闫玮 +9 位作者 王新强 殷景志 姜秀英 杨树人 杜国同 高鼎三 xiang liu Hui Cao Junying Xu R.P.H.Chang 《半导体光电》 CAS CSCD 北大核心 2001年第3期169-172,共4页
利用等离子体MOCVD设备在 (0 0 1)蓝宝石上生长了ZnO薄膜。通过对在不同条件下生长的薄膜样品X射线衍射的测量和分析 ,优化了薄膜的生长条件 ,长出了半高宽仅为 0 .15°的单一取向的高质量ZnO薄膜 ,并发现生长过程中多次退火或掺氮... 利用等离子体MOCVD设备在 (0 0 1)蓝宝石上生长了ZnO薄膜。通过对在不同条件下生长的薄膜样品X射线衍射的测量和分析 ,优化了薄膜的生长条件 ,长出了半高宽仅为 0 .15°的单一取向的高质量ZnO薄膜 ,并发现生长过程中多次退火或掺氮在薄膜中引入了张应力 ,而生长结束后一次退火却引入了压应力。 展开更多
关键词 等离子体MOCVD X射线衍射 氧化锌薄膜 退火工艺 生长条件
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Endoscopic full-thickness resection vs surgical resection for gastric stromal tumors: Efficacy and safety using propensity score matching
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作者 Si-Qiao Zhao Si-Yao Wang +6 位作者 Nan Ge Jin-Tao Guo xiang liu Guo-Xin Wang Lei Su Si-Yu Sun Sheng Wang 《World Journal of Gastrointestinal Surgery》 2025年第3期95-105,共11页
BACKGROUND Endoscopic full-thickness resection(EFTR)is increasingly used for treating gastrointestinal stromal tumors(GISTs)in the stomach.AIM To compare the efficacy,tolerability,and clinical outcomes of EFTR vs surg... BACKGROUND Endoscopic full-thickness resection(EFTR)is increasingly used for treating gastrointestinal stromal tumors(GISTs)in the stomach.AIM To compare the efficacy,tolerability,and clinical outcomes of EFTR vs surgical resection(SR)for gastric GISTs.METHODS We collected clinical data from patients diagnosed with GISTs who underwent either EFTR or SR at our hospital from October 2011 to July 2024.Patients were matched in a 1:1 ratio based on baseline characteristics and tumor clinical-pathological features using propensity score matching.We analyzed perioperative outcomes and follow-up data.The primary outcome measure was progressionfree survival(PFS).RESULTS Out of 912 patients,573 met the inclusion criteria.After matching,each group included 95 patients.The EFTR group demonstrated statistically significant advantages over the SR group in average operative time(P<0.001),length of hospital stay(P<0.001),time to resume liquid diet(P<0.001),incidence of adverse events(P=0.031),and hospitalization costs(P<0.001).The en bloc resection rate was significantly different,with SR group at 100%and EFTR group at 93.7%(P=0.038).The median follow-up was 2451.50 days.Recurrence occurred in 3 patients in the EFTR group and 4 patients in the SR group,with no statistically significant difference(P=1.000).Factors associated with PFS included age,tumor size,high-risk category in the modified National Institutes of Health(NIH)risk score,and resection status.Resection status was identified as an independent prognostic factor for PFS(P=0.0173,hazard ratios=0.0179,95%CI:0.000655-0.491).Notably,there was no statistically significant difference in PFS between the two groups.CONCLUSION This study is a non-inferiority design.The EFTR group significantly outperformed the SR group in terms of operative time,length of hospital stay,time to resume a liquid diet,incidence of adverse events,and hospitalization costs,demonstrating its higher economic efficiency and better tolerability.Additionally,although the en bloc resection rate was lower in the EFTR group compared to the SR group,there were no significant differences in tumor recurrence rates and progression-free survival between the two groups.This study found no statistical difference in the primary endpoint of postoperative recurrence rates between the two groups.However,due to sample size limitations,this result requires further validation in larger-scale studies.The current results should be viewed as exploratory evidence. 展开更多
关键词 Endoscopic full-thickness resection Gastrointestinal stromal tumors Surgical resection Propensity score matching EFFICACY Progression-free survival
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Calibration and Reliability Analysis of Eccentric Compressive Concrete Column with High Strength Rebars
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作者 Baojun Qin Hong Jiang +1 位作者 Wei Zhang xiang liu 《Structural Durability & Health Monitoring》 2025年第5期1203-1220,共18页
The utilization of high-strength steel bars(HSSB)within concrete structures demonstrates significant advantages in material conservation and mechanical performance enhancement.Nevertheless,existing design codes exhibi... The utilization of high-strength steel bars(HSSB)within concrete structures demonstrates significant advantages in material conservation and mechanical performance enhancement.Nevertheless,existing design codes exhibit limitations in addressing the distinct statistical characteristics of HSSB,particularly regarding strength design parameters.For instance,GB50010-2010 fails to specify design strength values for reinforcement exceeding 600 MPa,creating technical barriers for advancing HSSB implementation.This study systematically investigates the reliability of eccentric compression concrete columns reinforced with 600 MPa-grade HSSB through high-order moment method analysis.Material partial factors were calibrated against target reliability indices prescribed by GB50068-2018,incorporating critical variables including live-to-dead load ratios,design methodologies,and service conditions.The findings show that the value of k significantly affects the calibration of material partial factors,impacting the reliability of bearing capacity.Considering various k values and target reliability indices,it is recommended that the material partialfactorbe setat1.15,implyingthatthedesignstrengthfor600MPahigh-strengthsteelbars shouldbe considered as 522 MPa.For safety levels I and II,load adjustment factors of 1.1 and 0.9,respectively,may be applied. 展开更多
关键词 Reliability high-strength steel rebar concrete column material partial factor high-order moment method failure probability
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Autophagy in Schwann cells:A potential pharmacotherapeutic target in diabetic peripheral neuropathy
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作者 Qi-Chang Xing Jia Chen +3 位作者 Zheng liu Wen-Can Li xiang liu Wei Li 《World Journal of Diabetes》 2025年第6期89-103,共15页
Diabetic peripheral neuropathy(DPN)is a common complication of diabetes and is characterized by sensory and motor impairments resulting from neural injury.Schwann cells(SCs),which are important for peripheral nerve fu... Diabetic peripheral neuropathy(DPN)is a common complication of diabetes and is characterized by sensory and motor impairments resulting from neural injury.Schwann cells(SCs),which are important for peripheral nerve function,are compromised under hyperglycemic conditions,leading to impaired axonal re-generation and demyelination.Autophagy,a cellular degradation process,is essential for SC function and significantly influences DPN progression.This article highlights the significance of autophagy in SCs and its potential as a pharmacotherapeutic target in DPN.We discuss the mechanisms of autophagy in SCs,including the mammalian target of rapamycin,adenosine monophosphate-activated protein kinase,and phosphatase and tensin homolog-induced putative kinase/parkin pathways,and their dysregulation in DPN.This article also exa-mines various natural products and chemical agents that modulate autophagy and enhance the efficacy of DPN treatment.These agents target key signaling pathways,such as adenosine monophosphate-activated protein kinase/mam-malian target of rapamycin and demonstrate potential in promoting nerve re-generation and restoring SC function.The roles of exosomes,long non-coding RNA,and proteins in the regulation of autophagy have also been explored.In conclusion,targeting autophagy in SCs is a promising strategy for DPN treatment and offers new insights into therapeutic interventions.Further research is war-ranted to fully exploit these targets for clinical applications. 展开更多
关键词 AUTOPHAGY Schwann cells Diabetic peripheral neuropathy Adenosine mo-nophosphate-activated protein kinase Mammalian target of rapamycin AGENT
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工作应激与健康体检人群心电图异常表现的相关性分析 被引量:14
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作者 刘翔 赵君 洪艳玲 《中国现代医学杂志》 CAS 北大核心 2017年第28期102-105,共4页
目的探讨工作应激对健康体检人群心电图表现的影响。方法选取2015年6月-2016年1月在泸州市人民医院接受健康体检的人群282例。依据职业紧张压力量表OSI评分分为工作应激高水平组(≤15分)和工作应激低水平组(>15分),比较两组受检者的... 目的探讨工作应激对健康体检人群心电图表现的影响。方法选取2015年6月-2016年1月在泸州市人民医院接受健康体检的人群282例。依据职业紧张压力量表OSI评分分为工作应激高水平组(≤15分)和工作应激低水平组(>15分),比较两组受检者的心电图异常情况。结果健康体检282例,心电图异常57例,其中ST-T段改变21例,Q-Tc间期延长15例,P-R间期延长12例,传导阻滞9例,窦性心律不齐6例,心律失常6例,心电轴左偏3例,心房颤动3例,早搏3例,其他9例。工作应激高水平组159例,心电图异常45例(28.30%),工作应激低水平组123例,心电图异常12例(9.76%)。工作应激高水平组≤40岁、41~59岁、≥60岁人群心电图异常率分别为10.00%、30.00%和38.46%;工作应激低水平组≤40岁、41~59岁、≥60岁人群心电图异常率分别为7.69%、5.56%和20.00%。两组受检者41~59岁、≥60岁人群心电图异常率的比较,差异有统计学意义(P<0.05)。年龄、工种、工作应激是影响健康体检人群心电图表现的危险因素。结论工作应激是引起以ST-T段改变、Q-Tc间期延长为主的心电图异常改变的危险因素,应激水平越高,心电图异常率随之增加,且对中老年人群影响更大。 展开更多
关键词 工作应激 心电图 年龄 异常
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Heterojunctions engineered electron-deficient Co/oxygen vacancy-rich MnO_(2) triggers local built-in electric field within porous carbon fiber for PMS activation and rapid pollutant degradation
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作者 Zhenxiao Wang Shuguang Ning +10 位作者 xiang liu Hongyao Zhao Wanyu Zhang Liying Cao Yanyun Wang Danhong Shang Linzhi Zhai Tongyi Yang Feng Zeng Yangping Zhang Fu Yang 《Rare Metals》 2025年第10期7486-7499,共14页
The advanced oxidation process presents a perfect solution for eliminating organic pollutants in water resources,and the local microenvironment and surface state of metal reactive sites are crucial for the selective a... The advanced oxidation process presents a perfect solution for eliminating organic pollutants in water resources,and the local microenvironment and surface state of metal reactive sites are crucial for the selective activation of peroxomonosulfate(PMS),which possibly determines the degradation pathways of organic contaminants.In this study,by virtue of the precursor alternation,we constructed the state-switched dual metal species with the porous carbon fibers through the electrospinning strategy.Impressively,the optimal catalyst,featuring the electron-deficient cobalt surface oxidative state and most abundant oxygen vacancies(Ov)with MnO_(2)within porous carbon fibers,provides abundant mesoporosity,facilitating the diffusion and accommodation of big carbamazepine molecules during the reaction process.Benefiting from the tandem configuration of carbon fiber-encapsulated nanocrystalline species,a p-n heterojunction configuration evidenced by Mott-Schottky analysis induced local built-in electric field(BIEF)between electron-deficient cobalt and Ov-rich MnO_(2)within carbon matrix-mediated interfacial interactions,which optimizes the adsorption and activation of PMS and intermediates,increases the concentration of reactive radicals around the active site,and significantly enhances the degradation performance.As a result,the optimal catalyst could achieve 100%degradation of 20 ppm carbamazepine(CBZ)within only 4 min with a rate constant of 1.099 min^(-1),showcasing a low activation energy(50 kJ mol^(-1)),obviously outperforming the other counterparts.We further demonstrated the generation pathways of active species by activation of PMS mainly including sulfate radical(·SO_(4)^(-)),hydroxyl radical(·OH),superoxide radicals(·O_(2)^(-)),and singlet oxygen(^(1)O_(2)),unveiling their contribution to CBZ degradation.The degradation route of CBZ and toxicity analysis of various intermediates were further evaluated.By anchoring the optimal catalyst onto polyester fiber sponge,the photothermal conversion synergistic monolith floatable catalyst and its easy recovery can be achieved,showing good reproducibility and generalizability in the practical application. 展开更多
关键词 Advanced oxidation Heterojunction engineering Oxygen vacancies Integral degradation devices Built-in electric field
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积极应对川西高原气候变化影响和风险的策略研究
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作者 向柳 何蓉 +2 位作者 陈明扬 李言洁 文新茹 《绿色科技》 2025年第20期28-33,共6页
作为青藏高原的重要组成部分,川西高原生态环境非常脆弱,对全球气候变化较为敏感。通过科学考察和文献梳理发现,气候变化已经导致并将继续加剧川西高原冰川冻土消融、水文特征改变、生态系统演替,影响湿地生态系统功能和生物多样性,威... 作为青藏高原的重要组成部分,川西高原生态环境非常脆弱,对全球气候变化较为敏感。通过科学考察和文献梳理发现,气候变化已经导致并将继续加剧川西高原冰川冻土消融、水文特征改变、生态系统演替,影响湿地生态系统功能和生物多样性,威胁江河源生态安全,增大滑坡、泥石流等山地灾害风险,干扰电力供应稳定,威胁农牧业、旅游业等产业可持续发展。亟须基于科学评估和预测,精准识别川西高原的气候变化影响和风险,从观测和研究、自然生态系统、经济社会系统、支撑保障等方面针对性、系统性地采取了适应措施,提升高原气候适应型发展能力,促进高原人与自然和谐共生和可持续发展。 展开更多
关键词 气候变化 影响 风险 适应 川西高原
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Investigation into the characteristics of magnesite tailings-catalyzed gasification of petroleum coke
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作者 Xian-Chao Du xiang liu +1 位作者 Qian-Yun liu Bing Wang 《Petroleum Science》 2025年第9期3830-3842,共13页
This study systematically investigated the catalytic gasification of two distinct petroleum coke(PC)using magnesium-based tailings(MT)as the catalyst.The research objectives focused on comparative analysis of gasifica... This study systematically investigated the catalytic gasification of two distinct petroleum coke(PC)using magnesium-based tailings(MT)as the catalyst.The research objectives focused on comparative analysis of gasification reactivities and elucidation of carbon microstructure evolution during PC gasification.Experimental results demonstrate that PC-B(derived from Liaohe Oilfields delayed coking)exhibited significantly higher gasification activity than PC-A(from Karamay Oilfields delayed coking),with aromatic C–H content and polycondensation index showing stronger correlations with reactivity than graphitization parameters.Notably,the MT catalyst exhibited material-dependent catalytic behaviors during gasification.MT catalyst enhanced structural ordering in PC-B by:(i)developing denser aromatic carbon layers,(ii)improving microcrystalline alignment,and(iii)elevating graphitization degree.These structural modifications contrasted sharply with PC-A’s response,where MT introduction generated active MgO species in the ash phase,boosting gasification reactivity.Conversely,in PC-B ash systems,MgO preferentially reacted with Al_(2)O_(3) to form inert MgAl_(2)O_(4) spinel,effectively deactivating the catalyst.Kinetic investigations validated the shrinking core model(SCM)as the dominant mechanism,with calculated activation energies of 172.12 kJ/mol(PC-A+5%MT)and 137.19 kJ/mol(PC-B+5%MT). 展开更多
关键词 Petroleum coke Catalytic gasification Mg-based tailings Carbon microstructure KINETICS
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