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Biodiversity Characteristics and Protection Countermeasures of Yuncheng Salt Lake
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作者 Yan GUAN yu zhang +2 位作者 Quanxi zhang Ruinan GAO Donggang GUO 《Asian Agricultural Research》 2025年第5期1-7,共7页
[Objectives]To explore biodiversity characteristics of Yuncheng Salt Lake and provide protection countermeasures.[Methods]According to the field survey data of 978 plant quadrats and cluster analysis,species diversity... [Objectives]To explore biodiversity characteristics of Yuncheng Salt Lake and provide protection countermeasures.[Methods]According to the field survey data of 978 plant quadrats and cluster analysis,species diversity indicators such as Margalef richness index and Shannon-Wiener index were selected to deeply explore the structure and diversity characteristics of higher plant communities in Yuncheng Salt Lake.[Results]There were 117 species belonging to 97 genera and 35 families of higher plants in Yuncheng Salt Lake,of which Asteraceae and Gramineae were dominant families,and the North Temperate Distribution Genus accounted for 27.35%of the total genera;according to profile coefficient method,the optimal cluster number was 7,which was divided into 7 plant community types,including Artemisia capillaris community and Suaeda glauca(Bunge)community;the Lolium perenne community was the highest(d=2.537),the Artemisia scoparia community was the best(E=0.658),the Suaeda salsa(L.)Pall community was the lowest(H′=1.779),and the spatial distribution of species showed a significant aggregation pattern.[Conclusions]We put forward some countermeasures for biodiversity protection,including constructing dynamic monitoring system,implementing adaptive management strategy and promoting multi-party collaborative governance,so as to provide scientific theoretical basis and practical guidance for ecological restoration and sustainable development of Yuncheng Salt Lake. 展开更多
关键词 Yuncheng SALT LAKE BIODIVERSITY Community classification Diversity index PROTECTION COUNTERMEASURES
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Slip rate and locking degree of Haiyuan fault zone,northeastern Qinghai-Xizang plateau,based on refined block model and GPS data
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作者 Yang Liu yuxuan Qiu +2 位作者 Jialiang Liu yu zhang Caijun Xu 《Geodesy and Geodynamics》 2025年第5期536-545,共10页
As a major fault in the northeastern Qinghai-Xizang Plateau,the Haiyuan fault zone is important for understanding the regional deformation.Aiming at the differences in the slip rate and locking degree obtained from di... As a major fault in the northeastern Qinghai-Xizang Plateau,the Haiyuan fault zone is important for understanding the regional deformation.Aiming at the differences in the slip rate and locking degree obtained from different studies,this study constructs a refined block model(including Qilian,Alxa,Ordos,Xining,Haiyuan,and Lanzhou blocks)and uses the grid search and simulated annealing methods to invert GPS data for slip rate and locking degree of the Haiyuan fault zone.The results are as follows:(1)The sinistral slip rates in the western,middle,and eastern segments are 4.93-5.22 mm/a,1.52-4.94 mm/a,and 0.43-1.18 mm/a,decreasing eastward on the whole,while the compression rates are 0.45-1.26 mm/a,0.58-2.62 mm/a,and3.52-4.48 mm/a,increasing eastward on the whole.(2)The locking depth of the western segment increases from about 5 km to about 20 km eastward;the middle segment decreases and then increases eastward;the eastern segment concentrates at about 20 km(PHI is about 0.86).(3)The slip deficit is relatively higher in the Lenglongling,Jinqianghe,Maomaoshan,and Liupanshan faults(averaging about 3.42 mm/a,4.16 mm/a,4.23 mm/a,and 3.43 mm/a within 20 km).(4)The Qilian,Alxa,Xining,Lanzhou,and Haiyuan blocks rotate clockwise,while the Ordos block rotates counterclockwise.Additionally,by comparing different block models,the Haiyuan block should be considered independently.The Haiyuan fault zone adjusts surrounding block movements and uplifts Liupanshan mountain tectonically.The results can provide important references for understanding the regional earthquake risk and deformation mechanism. 展开更多
关键词 Haiyuan fault zone Block model Locking degree Slip rate
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Cedrol ameliorates ulcerative colitis via myeloid differentiation factor 2-mediated inflammation suppression,with barrier restoration and microbiota modulation
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作者 Yi-Qing Zhao yu zhang +2 位作者 Yan Qin Rui-Ya zhang Jun-Ping Wang 《World Journal of Gastroenterology》 2026年第2期135-151,共17页
BACKGROUND Ulcerative colitis(UC)is a chronic and treatment-resistant disorder requiring potent therapeutics that are effective and safe.Cedrol(CE)is a bioactive natural product present in many traditional Chinese med... BACKGROUND Ulcerative colitis(UC)is a chronic and treatment-resistant disorder requiring potent therapeutics that are effective and safe.Cedrol(CE)is a bioactive natural product present in many traditional Chinese medicines.It is known for its suppression of inflammation and mitigation of oxidative stress.Its therapeutic efficacy and mechanistic underpinnings in UC remain uncharacterized.AIM To investigate the therapeutic potential and mechanisms of CE in UC.METHODS The anti-inflammatory activity and intestinal barrier-repairing effects of CE were assessed in a dextran sulfate sodium-induced murine colitis model.Network pharmacology was employed to predict potential targets and pathways.Then molecular docking and dynamics simulations were utilized to confirm a stable interaction between CE and the toll-like receptor 4(TLR4)/myeloid differentiation factor 2(MD2)complex.The anti-inflammatory mechanisms were further verified using in vitro assays.Additionally,the gut microbiota composition was analyzed via 16S rRNA gene sequencing.RESULTS CE significantly alleviated colitis symptoms,mitigated histopathological damage,and suppressed inflammation.Moreover,CE restored intestinal barrier integrity by enhancing mucus secretion and upregulating tight junction proteins(zonula occludens 1,occludin,claudin-1).Mechanistically,CE stably bound to MD2,inhibiting lipopolysaccharide-induced TLR4 signaling in RAW264.7 cells.This led to suppression of the downstream mitogen-activated protein kinase and nuclear factor kappa B signaling pathways,downregulating the expression of tumor necrosis factor-alpha,interleukin-1β,and interleukin-6.Gut microbiota analysis revealed that CE reversed dextran sulfate sodium-induced dysbiosis with significant enrichment of butyrogenic Christensenella minuta.CONCLUSION CE acted on MD2 to suppress proinflammatory cascades,promoting mucosal barrier reconstitution and microbiota remodeling and supporting its therapeutic use in UC. 展开更多
关键词 CEDROL Ulcerative colitis Toll-like receptor 4 Myeloid differentiation factor 2 Signaling pathways Gut microbiota
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Bearing Fault Diagnosis Based on Multimodal Fusion GRU and Swin-Transformer
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作者 Yingyong Zou yu zhang +2 位作者 Long Li Tao Liu Xingkui zhang 《Computers, Materials & Continua》 2026年第1期1587-1610,共24页
Fault diagnosis of rolling bearings is crucial for ensuring the stable operation of mechanical equipment and production safety in industrial environments.However,due to the nonlinearity and non-stationarity of collect... Fault diagnosis of rolling bearings is crucial for ensuring the stable operation of mechanical equipment and production safety in industrial environments.However,due to the nonlinearity and non-stationarity of collected vibration signals,single-modal methods struggle to capture fault features fully.This paper proposes a rolling bearing fault diagnosis method based on multi-modal information fusion.The method first employs the Hippopotamus Optimization Algorithm(HO)to optimize the number of modes in Variational Mode Decomposition(VMD)to achieve optimal modal decomposition performance.It combines Convolutional Neural Networks(CNN)and Gated Recurrent Units(GRU)to extract temporal features from one-dimensional time-series signals.Meanwhile,the Markovian Transition Field(MTF)is used to transform one-dimensional signals into two-dimensional images for spatial feature mining.Through visualization techniques,the effectiveness of generated images from different parameter combinations is compared to determine the optimal parameter configuration.A multi-modal network(GSTCN)is constructed by integrating Swin-Transformer and the Convolutional Block Attention Module(CBAM),where the attention module is utilized to enhance fault features.Finally,the fault features extracted from different modalities are deeply fused and fed into a fully connected layer to complete fault classification.Experimental results show that the GSTCN model achieves an average diagnostic accuracy of 99.5%across three datasets,significantly outperforming existing comparison methods.This demonstrates that the proposed model has high diagnostic precision and good generalization ability,providing an efficient and reliable solution for rolling bearing fault diagnosis. 展开更多
关键词 MULTI-MODAL GRU swin-transformer CBAM CNN feature fusion
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Innovative Strategies to Overcome Stability Challenges of Single‑Atom Nanozymes
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作者 Rong Guo Qiuzheng Du +3 位作者 Yaping He Haoan Wu yu zhang Ziwei Jing 《Nano-Micro Letters》 2026年第3期725-756,共32页
Single-atom nanozymes(SAzymes)exhibit exceptional catalytic efficiency due to their maximized atom utilization and precisely modulated metalcarrier interactions,which have attracted significant attention in the biomed... Single-atom nanozymes(SAzymes)exhibit exceptional catalytic efficiency due to their maximized atom utilization and precisely modulated metalcarrier interactions,which have attracted significant attention in the biomedical field.However,stability issues may impede the clinical translation of SAzymes.This review provides a comprehensive overview of the applications of SAzymes in various biomedical fields,including disease diagnosis(e.g.,biosensors and diagnostic imaging),antitumor therapy(e.g.,photothermal therapy,photodynamic therapy,sonodynamic therapy,and immunotherapy),antimicrobial therapy,and anti-oxidative stress therapy.More importantly,the existing challenges of SAzymes are discussed,such as metal atom clustering and active site loss,ligand bond breakage at high temperature,insufficient environment tolerance,biosecurity risks,and limited catalytic long-term stability.Finally,several innovative strategies to address these stability concerns are proposed—synthesis process optimization(space-limited strategy,coordination site design,bimetallic synergistic strategy,defect engineering strategy,atom stripping-capture),surface modification,and dynamic responsive design—that collectively pave the way for robust,clinically viable SAzymes. 展开更多
关键词 Single-atom nanozymes Clinical translation Stability issues Innovative strategies BIOCOMPATIBILITY
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Differentiating the 2D Passivation from Amorphous Passivation in Perovskite Solar Cells
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作者 Xiaojian Zheng Shehzad Ahmed +12 位作者 yu zhang Guoqiang Xu Junyu Wang Di Lu Tingshu Shi Jun Tang Lei Yan Wei Chen Peigang Han Zhixin Liu Danish Khan Xingzhu Wang Zeguo Tang 《Nano-Micro Letters》 2026年第2期631-643,共13页
The introduction of two-dimensional(2D)perovskite layers on top of three-dimensional(3D)perovskite films enhances the performance and stability of perovskite solar cells(PSCs).However,the electronic effect of the spac... The introduction of two-dimensional(2D)perovskite layers on top of three-dimensional(3D)perovskite films enhances the performance and stability of perovskite solar cells(PSCs).However,the electronic effect of the spacer cation and the quality of the 2D capping layer are critical factors in achieving the required results.In this study,we compared two fluorinated salts:4-(trifluoromethyl)benzamidine hydrochloride(4TF-BA·HCl)and 4-fluorobenzamidine hydrochloride(4F-BA·HCl)to engineer the 3D/2D perovskite films.Surprisingly,4F-BA formed a high-performance 3D/2D heterojunction,while4TF-BA produced an amorphous layer on the perovskite films.Our findings indicate that the balanced intramolecular charge polarization,which leads to effective hydrogen bonding,is more favorable in 4F-BA than in 4TF-BA,promoting the formation of a crystalline 2D perovskite.Nevertheless,4TF-BA managed to improve efficiency to 24%,surpassing the control device,primarily due to the natural passivation capabilities of benzamidine.Interestingly,the devices based on 4F-BA demonstrated an efficiency exceeding 25%with greater longevity under various storage conditions compared to 4TF-BA-based and the control devices. 展开更多
关键词 3D/2D perovskite films Benzamidine Amorphous passivation 2D passivation Inverted perovskite solar cells
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Multifunctional Waterborne Polyurethane Nanocomposite Films with Remarkable Electromagnetic Interference Shielding,Electrothermal and Solarthermal Performances 被引量:2
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作者 Ming-Ke Xu Xin-Jie Luo +4 位作者 Hao-Bin zhang yu zhang Lulu Li Xin-Feng Zhou Zhong-Zhen yu 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2023年第2期267-277,共11页
To impart polymers with high electrical conductivity and satisfactory electromagnetic interference shielding efficiency,it is crucial to efficiently construct interconnecting networks of conductive nanofillers in poly... To impart polymers with high electrical conductivity and satisfactory electromagnetic interference shielding efficiency,it is crucial to efficiently construct interconnecting networks of conductive nanofillers in polymer matrices.Herein,on the basis of the three-dimensional(3D)skeleton and volume-exclusion effect of silane-modified tetra-needle ZnO(ST-ZnO)whiskers and the high conductivity of two-dimensional MXene nanosheets,multifunctional MXene/ST-ZnO/waterborne polyurethane(MTW)nanocomposite films are fabricated by coating of MXene on ST-ZnO followed by compounding with waterborne polyurethane.The 3D four-needles of the whiskers facilitate the formation of an interconnecting network in the waterborne polyurethane matrix,while the coating of MXene efficiently makes the interconnecting network of the whiskers conductive at a low amount of the MXene.The resultant MTW ternary nanocomposite film exhibits not only a high electrical conductivity of 4.8×10^(4)S/m,but also an excellent electromagnetic interference shielding effectiveness of over 70 dB in the X-band at a low thickness of 100µm.In addition,the ternary film also exhibits outstanding Joule heating performances with an equilibrium temperature of 113℃at a low driving voltage of 3 V.The multifunctional nanocomposite films are promising for applications in portable and wearable electronics and flexible electromagnetic interference shielding devices. 展开更多
关键词 Electrical conductivity Electromagnetic interference shielding Nanocomposite films Waterborne polyurethane MXene nanosheets
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免疫治疗耐药后组织学转化为不典型类癌的RET融合阳性NSCLC病例报道
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作者 张宇 张卉 +2 位作者 钟巍 陈闽江 王孟昭 《中国肺癌杂志》 北大核心 2025年第5期400-404,共5页
近年来,免疫检查点抑制剂(immune checkpoint inhibitors,ICIs)已成为驱动基因阴性晚期非小细胞肺癌(non-small cell lung cancer,NSCLC)治疗的基石,然而耐药不可避免且机制尚不明确。其中,组织学类型转化是罕见的免疫耐药机制,目前仅... 近年来,免疫检查点抑制剂(immune checkpoint inhibitors,ICIs)已成为驱动基因阴性晚期非小细胞肺癌(non-small cell lung cancer,NSCLC)治疗的基石,然而耐药不可避免且机制尚不明确。其中,组织学类型转化是罕见的免疫耐药机制,目前仅有个案报道。本文报道了首例经一线ICIs联合化疗后组织学类型转化为不典型类癌的肺腺癌,探讨了组织类型转化在NSCLC获得性免疫耐药机制中的关键作用。此外,患者携带转染重排基因(rearranged during transfection,RET)融合突变,在发生组织类型转化后试用塞普替尼治疗取得了良好的疗效,本例为合并罕见突变的不典型类癌患者提供了可能的药物治疗选择。 展开更多
关键词 肺肿瘤 免疫耐药 组织学转化 不典型类癌 高选择性RET抑制剂
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操作系统课程实践新路径探索--全国大学生计算机系统能力大赛操作系统设计赛“区域赛”
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作者 张羽 周庆国 +5 位作者 石亮 刘国军 陈鹏飞 刘刚 宫晓利 陈咸彰 《计算机教育》 2025年第11期15-21,共7页
针对操作系统课程实践教学面临的新挑战,借助“101计划”操作系统课程虚拟教研室平台,提出一条基于“区域赛”模式的操作系统课程“做中学”实践教学新路径,具体介绍2024年操作系统设计赛“区域赛”的实施情况,为全国高校操作系统课程... 针对操作系统课程实践教学面临的新挑战,借助“101计划”操作系统课程虚拟教研室平台,提出一条基于“区域赛”模式的操作系统课程“做中学”实践教学新路径,具体介绍2024年操作系统设计赛“区域赛”的实施情况,为全国高校操作系统课程实践教学改革和计算机类专业学生系统能力评价提供参考与启示。 展开更多
关键词 操作系统 101计划 实践教学 操作系统设计赛 泛在系统能力
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环指蛋白41调控胆管癌细胞增殖和转移的生物学作用
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作者 吴起杰 李勇 +4 位作者 张瑜 冉凤明 丁荣 张麒 杨银山 《昆明医科大学学报》 2025年第7期10-17,共8页
目的探讨环指蛋白41(ring finger protein 41,RNF41)在胆管癌发生和发展过程中的作用。方法通过生物信息学、Western blot和免疫组织化学分析2010年1月至2016年12月期间在昆明医科大学第二附属医院和昆明市甘美医院接受全手术切除的84... 目的探讨环指蛋白41(ring finger protein 41,RNF41)在胆管癌发生和发展过程中的作用。方法通过生物信息学、Western blot和免疫组织化学分析2010年1月至2016年12月期间在昆明医科大学第二附属医院和昆明市甘美医院接受全手术切除的84例胆管癌患者肿瘤组织和癌旁正常组织中RNF41的mRNA和蛋白质的表达;利用TIMER 2.0数据库中临床资料分析RNF41对胆管癌患者预后生存的影响,分析RNF41与肿瘤临床特点的关系;RNF41 siRNA经转染HCC9810、RBE、HUCCT1细胞后,利用CCK-8、Edu、克隆形成实验和Western blot实验,分析敲低RNF41组和对照组胆管癌细胞的增殖作用的变化;利用Transwell实验和EMT标记物及迁移标记物检测分析敲低RNF41组和对照组胆管癌细胞的侵袭作用的变化,Western blot实验检测敲低RNF41对胆管癌细胞上皮间质的转化作用;12只BALB/c小鼠,随机分为两组,对照组和敲低RNF41组,每组各6只,进行裸鼠成瘤实验、Western blot实验和免疫组织化学染色分析敲低RNF41对动物体内肿瘤生长的影响。结果实时定量荧光PCR分析显示胆管癌肿瘤组织中RNF41 mRNA表达水平明显高于相应的癌旁组织(P<0.01),免疫组织化学染色评价RNF41的蛋白表达水平结果与其一致。TIMER 2.0数据库分析RNF41与胆管癌的分级,分期、淋巴结转移及生存期的关系,结果显示RNF41的表达与CHOL组织学分级和肿瘤淋巴结转移阶段密切相关(P<0.01);生存分析显示RNF41的高表达又与CHOL患者的不良预后密切相关。CCK-8、EdU、克隆形成实验显示在胆管癌细胞中与对照组组相比,敲低RNF41组抑制肿瘤细胞的增殖能力;Westernblot结果显示与对照组相比干扰RNF41组肿瘤细胞EMT标志物E-cadherin的水平显著提高,Ncadherin和MMP9的水平降低(P<0.05)。然而,通过在裸鼠体内进行异体肿瘤移植实验和检测EMT标志蛋白发现,与体外细胞实验分析一致的EMT相关蛋白检测结果(P<0.01);此外与对照组相比RNF41敲低组抑制了裸鼠体内胆管癌细胞皮下成瘤的能力(P<0.05)。结论RNF41可促进胆管癌的发生和发展,并与临床病理特征及患者的不良预后密切相关,敲低RNF41对胆管癌细胞的增殖、侵袭、EMT和肿瘤形成都有抑制作用。 展开更多
关键词 胆管癌 环指蛋白41 增殖 侵袭
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Evaluation on the Competitiveness of the Agribusiness with Plateau Characteristics in Yunnan Province Based on AHP
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作者 Yingmei GUO Xiaoli ZHU yu zhang 《Asian Agricultural Research》 2016年第7期14-20,共7页
The development of agriculture with plateau characteristics is a market-oriented strategic choice,made by Yunnan Province,of agricultural economy with regional characteristics,on the basis of resources and location ad... The development of agriculture with plateau characteristics is a market-oriented strategic choice,made by Yunnan Province,of agricultural economy with regional characteristics,on the basis of resources and location advantages,as well as geographical division of the national economy. The characteristic agribusiness is an important carrier for building a new agricultural management system with plateau characteristics,and also a key way to promote characteristic agricultural industrialization. In this paper,with 26 agribusinesses with plateau characteristics in Yunnan Province as samples,we establish the competitiveness evaluation system for the agribusiness with plateau characteristics,and use the operating data( 2012-2014) and AHP to calculate and the sample business competitiveness index and sort these businesses. Finally,we make a comprehensive analysis on the competitiveness of sample agribusinesses with plateau characteristics in Yunnan Province,in order to provide decision-making basis for promotion of the competitiveness of the agribusiness with plateau characteristics. 展开更多
关键词 PLATEAU CHARACTERISTICS Agribusiness COMPETITIVENESS YUNNAN
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中国主流媒体平台建设的实践路径与挑战--基于中西方差异视角的分析
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作者 蔡雯 张宇 《新媒体与社会》 2025年第1期126-142,460,共18页
平台建设已成为中国主流媒体推进媒体深度融合的重要路径,然而,平台化在中西方新闻实践中的内涵与实践存在显著差异。本文对比中西方新闻业平台化实践在话语观念、实践形态和结构关系上的差异,认为中国主流媒体的平台化是一种系统性、... 平台建设已成为中国主流媒体推进媒体深度融合的重要路径,然而,平台化在中西方新闻实践中的内涵与实践存在显著差异。本文对比中西方新闻业平台化实践在话语观念、实践形态和结构关系上的差异,认为中国主流媒体的平台化是一种系统性、生态化的资源配置实践,结合对《人民日报》、《北京日报》和《新京报》三家媒体平台建设历程的案例分析,总结了中国主流媒体平台建设的微观、中观与宏观三条实践路径,并分析其在定位布局、技术功能和运营管理三个方面存在的问题与挑战。本文认为,主流媒体平台建设需要政府、企业、媒体、公众等多方协同、系统推进,从而推动主流媒体实现更高效、更有力的舆论引导和社会服务功能。 展开更多
关键词 主流媒体 平台化 平台建设 新闻资源配置 中西方比较
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产教深度融合新形势下面向图计算拔尖人才培养的教学改革
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作者 张宇 赵苑君 《计算机教育》 2025年第11期130-135,共6页
针对当前图计算领域拔尖人才培养在产教深度融合新形势情况下面临的问题,提出图计算技术综合教学改革新思路,介绍教学改革实践过程,最后说明教学改革效果,旨在为同类高等院校计算机类课程教学提供有效参考。
关键词 产教深度融合 拔尖人才 课程体系 教学改革
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固体酸催化剂的研究进展 被引量:1
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作者 张宇 张睿 +3 位作者 王子健 汪啸 宋术岩 张洪杰 《化学学报》 北大核心 2025年第2期152-169,共18页
固体酸是一类制备过程简单、环境污染小且催化活性高的催化材料,在烷基化、异构化和酯化反应等多种化学过程中表现出卓越的催化活性.然而,其稳定性不足和再生活性低下的问题,很大程度上制约了其在大规模工业生产中的应用.因此,开发兼具... 固体酸是一类制备过程简单、环境污染小且催化活性高的催化材料,在烷基化、异构化和酯化反应等多种化学过程中表现出卓越的催化活性.然而,其稳定性不足和再生活性低下的问题,很大程度上制约了其在大规模工业生产中的应用.因此,开发兼具高活性和高稳定性的新型固体酸催化剂具有极其重要的研究价值和意义.本综述介绍了常用固体酸催化剂的概念、分类、合成方法以及表征技术,并引入一些经过稀土改性的固体酸催化剂的应用研究进展.本综述主要着重于研究固体酸催化剂酸性质对于催化性能的影响(如酸强度、酸含量、酸位点种类等),而不是传统的物化性质(如比表面积、晶相、表面形貌等).最后,对固体酸催化剂的发展前景进行了展望. 展开更多
关键词 固体酸 催化剂 合成 表征 稀土
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高效靶向示踪钙钛矿纳米系统光电增效抗肿瘤
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作者 李坚 张毓 +8 位作者 闫融融 孙开媛 刘晓晴 梁子尚 焦忆楠 卜晖 陈欣 赵晋津 施剑林 《物理化学学报》 北大核心 2025年第5期124-144,共21页
金属卤化物钙钛矿由于其多维度的晶体结构和优良的荧光成像/示踪及光电转换性质,使其成为一种非常具有前瞻性的光电增效治疗肿瘤材料。然而,传统卤化物钙钛矿纳米晶的水稳定性问题,限制了其应用于生物成像和光电增效肿瘤治疗的药物递送... 金属卤化物钙钛矿由于其多维度的晶体结构和优良的荧光成像/示踪及光电转换性质,使其成为一种非常具有前瞻性的光电增效治疗肿瘤材料。然而,传统卤化物钙钛矿纳米晶的水稳定性问题,限制了其应用于生物成像和光电增效肿瘤治疗的药物递送纳米系统研究。本文将甲氨蝶呤-壳聚糖-叶酸(MTX-CS-FA)成功与钙钛矿纳米晶体CsSn_(0.5)Pb_(0.5)Br_(3)(PeNCs)铆钉连接,制备出了可以在水中稳定228 d且发绿光的PeNCs@MTX-CS-FA纳米载药体系。在可见光照射下,新型PeNCs@MTX-CS-FA纳米载药体系增效抗肿瘤治疗原理:钙钛矿纳米晶体产生电子和活性氧(ROS);钙钛矿光生空穴耗竭过表达的谷胱甘肽(GSH);甲氨蝶呤(MTX)抑制二氢叶酸还原酶(DHFR)活性,导致肿瘤细胞的脂质过氧化,上述三点共同作用抑制肿瘤细胞的增殖、促进肿瘤细胞凋亡。在动物体内实验中,采用小鼠移植肿瘤模型,累积用药量达2.4mg PeNCs@MTX-CS-FA纳米载药系统时,肿瘤体积减少了约63.68%和肿瘤重量下降了约63.26%。通过生物安全性评估实验证实,在治疗剂量下,小鼠肝、肾等器官功能正常,说明纳米体系具有良好的生物安全性,并且研究发现钙钛矿纳米颗粒经小鼠肠道排出,小鼠粪便呈现出与原始钙钛矿晶体相同的绿色荧光,金属卤化物钙钛矿纳米载药体系在生物成像和光电催化化疗方面呈现优异的增效抗肿瘤治疗效果。 展开更多
关键词 肿瘤治疗 生物成像 钙钛矿纳米颗粒 光电催化化疗
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电场诱导聚乳酸纳米纤维细化及其呼吸防护性能研究
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作者 张雨 李佳琪 +6 位作者 吴洋 李湘 王存民 邵将 徐欢 李世航 陈小雨 《高分子学报》 北大核心 2025年第11期2023-2032,共10页
针对传统熔喷滤材驻极性能差、不可降解及细颗粒物拦截效率低等瓶颈问题,将氯化锂(LiCl)引入立构复合聚乳酸(SC-PLA)体系,通过静电纺丝技术构建SC-PLA/LiCl超细纳米纤维.LiCl的引入增强了电场力对纤维的牵伸,使得SC-PLA纤维细化,得到平... 针对传统熔喷滤材驻极性能差、不可降解及细颗粒物拦截效率低等瓶颈问题,将氯化锂(LiCl)引入立构复合聚乳酸(SC-PLA)体系,通过静电纺丝技术构建SC-PLA/LiCl超细纳米纤维.LiCl的引入增强了电场力对纤维的牵伸,使得SC-PLA纤维细化,得到平均纤维直径为385 nm的SC-PLA/LiCl纳纤膜.此外,LiCl促进了SC-PLA链在高压电场下的取向,使得SC-PLA/LiCl纤维的偶极电荷数量增多,电荷存储稳定性增强;SC-PLA/LiCl纳纤膜的相对介电常数和表面电势分别为纯SC-PLA纤维膜的1.6和2.1倍.得益于高孔隙率和显著提高的静电吸附能力,SC-PLA/LiCl纳纤膜在85 L/min的空气流量下对PM_(0.3)的过滤效率达95.7%,而空气阻力仅为181.2 Pa.此外,SC-PLA/LiCl纳纤膜摩擦电性能的增强使得其具有呼吸监测的能力.所制备的SC-PLA/LiCl超细纳米纤维在长效呼吸防护与个人健康管理领域有着巨大的应用潜力. 展开更多
关键词 聚乳酸 纳米纤维膜 静电纺丝 空气过滤 颗粒物
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Flexible Graphene Field‑Effect Transistors and Their Application in Flexible Biomedical Sensing 被引量:1
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作者 Mingyuan Sun Shuai Wang +5 位作者 Yanbo Liang Chao Wang yunhong zhang Hong Liu yu zhang Lin Han 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期252-313,共62页
Flexible electronics are transforming our lives by making daily activities more convenient.Central to this innovation are field-effect transistors(FETs),valued for their efficient signal processing,nanoscale fabricati... Flexible electronics are transforming our lives by making daily activities more convenient.Central to this innovation are field-effect transistors(FETs),valued for their efficient signal processing,nanoscale fabrication,low-power consumption,fast response times,and versatility.Graphene,known for its exceptional mechanical properties,high electron mobility,and biocompatibility,is an ideal material for FET channels and sensors.The combination of graphene and FETs has given rise to flexible graphene field-effect transistors(FGFETs),driving significant advances in flexible electronics and sparked a strong interest in flexible biomedical sensors.Here,we first provide a brief overview of the basic structure,operating mechanism,and evaluation parameters of FGFETs,and delve into their material selection and patterning techniques.The ability of FGFETs to sense strains and biomolecular charges opens up diverse application possibilities.We specifically analyze the latest strategies for integrating FGFETs into wearable and implantable flexible biomedical sensors,focusing on the key aspects of constructing high-quality flexible biomedical sensors.Finally,we discuss the current challenges and prospects of FGFETs and their applications in biomedical sensors.This review will provide valuable insights and inspiration for ongoing research to improve the quality of FGFETs and broaden their application prospects in flexible biomedical sensing. 展开更多
关键词 FLEXIBLE GRAPHENE Field-effect transistor WEARABLE IMPLANTABLE BIOSENSOR
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图式理论视角下海南省国际形象构建研究——基于X数据的实证探索 被引量:1
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作者 邓元兵 楚晨 张宇 《新媒体与社会》 2025年第1期110-125,459,460,共18页
在全球化传播背景下,社交媒体已成为城市国际形象传播的重要渠道。本研究以图式理论为指导,结合关键词提取、情感分析和主题建模技术,系统探讨海南省在X上的国际形象构建。研究利用KeyBert技术识别公众对海南热点的关注,通过情感分析揭... 在全球化传播背景下,社交媒体已成为城市国际形象传播的重要渠道。本研究以图式理论为指导,结合关键词提取、情感分析和主题建模技术,系统探讨海南省在X上的国际形象构建。研究利用KeyBert技术识别公众对海南热点的关注,通过情感分析揭示正面情感主要聚焦于生态环境与旅游优势,负面情感则集中在自然灾害和经济挑战等方面;进一步结合LDA主题建模提炼多维主题,提炼出国际影响力、发展潜力等核心维度,并提出针对性传播策略,为提升海南的国际认知度和吸引力提供理论支持与实践参考。 展开更多
关键词 海南省国际形象 图式理论 国际影响力
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Method for Estimating the State of Health of Lithium-ion Batteries Based on Differential Thermal Voltammetry and Sparrow Search Algorithm-Elman Neural Network 被引量:1
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作者 yu zhang Daoyu zhang TiezhouWu 《Energy Engineering》 EI 2025年第1期203-220,共18页
Precisely estimating the state of health(SOH)of lithium-ion batteries is essential for battery management systems(BMS),as it plays a key role in ensuring the safe and reliable operation of battery systems.However,curr... Precisely estimating the state of health(SOH)of lithium-ion batteries is essential for battery management systems(BMS),as it plays a key role in ensuring the safe and reliable operation of battery systems.However,current SOH estimation methods often overlook the valuable temperature information that can effectively characterize battery aging during capacity degradation.Additionally,the Elman neural network,which is commonly employed for SOH estimation,exhibits several drawbacks,including slow training speed,a tendency to become trapped in local minima,and the initialization of weights and thresholds using pseudo-random numbers,leading to unstable model performance.To address these issues,this study addresses the challenge of precise and effective SOH detection by proposing a method for estimating the SOH of lithium-ion batteries based on differential thermal voltammetry(DTV)and an SSA-Elman neural network.Firstly,two health features(HFs)considering temperature factors and battery voltage are extracted fromthe differential thermal voltammetry curves and incremental capacity curves.Next,the Sparrow Search Algorithm(SSA)is employed to optimize the initial weights and thresholds of the Elman neural network,forming the SSA-Elman neural network model.To validate the performance,various neural networks,including the proposed SSA-Elman network,are tested using the Oxford battery aging dataset.The experimental results demonstrate that the method developed in this study achieves superior accuracy and robustness,with a mean absolute error(MAE)of less than 0.9%and a rootmean square error(RMSE)below 1.4%. 展开更多
关键词 Lithium-ion battery state of health differential thermal voltammetry Sparrow Search Algorithm
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两种经直肠超声引导下穿刺方法对可疑前列腺癌的诊断效能比较 被引量:1
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作者 张玉 汪颖 《中国肿瘤临床》 北大核心 2025年第4期183-187,共5页
目的:探究经直肠常规超声引导下系统穿刺和经直肠超声造影成像(contrast-enhanced ultrasonography,CEUS)引导下靶向穿刺诊断可疑前列腺癌(prostate cancer,PCa)的诊断效能。方法:选择2021年2月至2024年2月在上海市奉贤区中心医院疑诊为... 目的:探究经直肠常规超声引导下系统穿刺和经直肠超声造影成像(contrast-enhanced ultrasonography,CEUS)引导下靶向穿刺诊断可疑前列腺癌(prostate cancer,PCa)的诊断效能。方法:选择2021年2月至2024年2月在上海市奉贤区中心医院疑诊为PCa的239例患者,有139例接受直肠CEUS引导下经直肠穿刺活检,采用靶向穿刺法,纳入造影组,有100例接受常规超声引导下直肠穿刺活检,采用12点穿刺法,纳入常规组。比较两组PCa检出率、有临床意义前列腺癌(clinically significant prostate cancer,CsPCa)检出率,并分析不同亚组间的PCa检出率;比较两组穿刺针数、单针阳性针数和穿刺相关并发症。结果:经手术病理结果证实,造影组经穿刺确诊PCa 75例(53.96%),良性病变64例(46.04%);常规组经穿刺确诊PCa 38例(38.00%),良性病变62例(62.00%)。造影组PCa检出率显著高于常规组(P<0.05)。造影组不同年龄、前列腺特异抗原(prostate specific antigen,PSA)水平之间的PCa检出率差异均有统计学意义(P<0.05),常规组不同PSA水平之间的PCa检出率差异有统计学意义(P<0.05),当年龄>70岁时,造影组PCa检出率显著高于常规组(P<0.05),当PSA水平>20 ng/mL时,造影组PCa检出率显著高于常规组(P<0.05),当前列腺体积在31~60 cm^(3)之间时,造影组PCa检出率显著高于常规组(P<0.05)。造影组靶向穿刺共计283针,常规组系统穿刺共计1 200针,造影组单针阳性率显著高于常规组(P<0.001)。两组穿刺相关并发症差异均无统计学意义(P>0.05)。结论:经直肠CEUS引导下靶向穿刺在PCa的诊断中具有较高的检出率和单针阳性率,尤其在高龄和高PSA水平患者中优势明显,且安全性良好。 展开更多
关键词 前列腺癌 超声造影成像 靶向穿刺 经直肠穿刺活检 系统穿刺 诊断效能
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