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大白菜水杨酸通路基因BraNPR1、BraTGA3参与调控芜菁花叶病毒侵染
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作者 高维芳 李雪 +5 位作者 赵程通 姜露 贾明轩 周雪平 李星 李方方 《植物保护》 北大核心 2026年第1期17-26,78,共11页
水杨酸是重要的植物激素与信号分子,通过调控免疫相关基因NPR1以及转录因子TGA等的表达,调节对入侵病原微生物的抗性。为了探讨大白菜水杨酸通路相关基因在植物与病毒互作中的功能,以芜菁花叶病毒(turnip mosaic virus,TuMV)敏感大白菜... 水杨酸是重要的植物激素与信号分子,通过调控免疫相关基因NPR1以及转录因子TGA等的表达,调节对入侵病原微生物的抗性。为了探讨大白菜水杨酸通路相关基因在植物与病毒互作中的功能,以芜菁花叶病毒(turnip mosaic virus,TuMV)敏感大白菜品种‘良庆’与本氏烟Nicotiana benthamiana为试验材料,研究NPR1、TGA3与TuMV之间的相互作用机制。通过同源性比对与进化关系分析,在大白菜基因组中鉴定到水杨酸信号通路相关基因BraNPR1与TGA基因家族的8个BraTGAs,RT-qPCR检测发现它们均能够响应TuMV的侵染。通过亚细胞定位分析、酵母双杂交以及双分子荧光互补试验,证明了BraNPR1能够与BraTGA3在细胞核中互作。进一步将TuMV分别与BraNPR1、BraTGA3共浸润本氏烟发现,过表达BraNPR1和BraTGA3促进病程相关蛋白PR1基因的表达,抑制了病毒侵染。综上,大白菜水杨酸通路相关基因BraNPR1与BraTGA3相互作用响应病毒侵染,参与对植物病毒的抗性。 展开更多
关键词 大白菜 芜菁花叶病毒 npr1 TGA3 相互作用机制
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Negative Coulomb drag between graphene quantum Hall edges
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作者 SONG Junwei GAN Qikang +4 位作者 ZHU Wang WATANABE Kenji TANIGUCHI Takashi YU Geliang WANG Lei 《物理学进展》 北大核心 2026年第1期1-12,共12页
Coulomb drag refers to the phenomenon in which a current driven through one conducting layer induces a voltage nearby,electrically isolated layer sorely through interlayer Coulomb interactions between charge carriers.... Coulomb drag refers to the phenomenon in which a current driven through one conducting layer induces a voltage nearby,electrically isolated layer sorely through interlayer Coulomb interactions between charge carriers.It has been extensively studied in various systems,including parallel nanowires,double quantum wells,and double-layer graphene.Here,we report the observation of Coulomb drag in a novel system consisting of two graphene layers separated laterally by a 30 nm gap within the material plane,exhibiting behavior distinct from that in vertical graphene heterostructures.Our experiments reveal pronounced negative drag resistances under an out-of-plane magnetic field at the quantum Hall edges,reaching a maximum when the carrier densities in both graphene layers are tuned to the charge neutrality point via gate voltages.Our work establish two separate and spatially closed quantum Hall edge modes as a new platform to explore electronic interaction physics between one dimensional systems. 展开更多
关键词 negative Coulomb drag quantum Hall edges van der Waals heterostructures
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Shear performance of NPR bolt under varying prestress levels
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作者 Wenhui Bian Kexue Wang +3 位作者 Jun Yang Qingshuo Hao Zhaoxi Zhai Xuefei Hong 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期528-541,共14页
The negative Poisson’s ratio(NPR)bolt is an innovative support element distinguished by its high strength,elongation,and a slightly negative Poisson’s ratio.Unlike conventional prestressed(PR)bolts with a positive P... The negative Poisson’s ratio(NPR)bolt is an innovative support element distinguished by its high strength,elongation,and a slightly negative Poisson’s ratio.Unlike conventional prestressed(PR)bolts with a positive Poisson’s ratio,the NPR bolt exhibits a quasi-ideal plastic response without a prominent yield platform,enabling it to sustain high prestress with a substantial safety margin,which is particularly advantageous for jointed rock masses.However,investigations into the shear resistance mechanisms of NPR bolts under varying prestress levels remain limited.This study conducted full-scale double shear tests to assess the shear strength,deformation behavior,energy absorption,and failure mechanisms of NPR bolts under different prestress conditions.To ensure a fair comparison with PR bolts,a prestress utilization coefficient(PUC)was introduced.The results reveal that at a PUC of 0.25,the NPR bolt achieved peak axial force,shear displacement,and peak shear force values that are 2.41,1.88,and 2.13 times greater than those of the PR bolt,respectively.Shear performance was optimized at a prestress level of 100 kN,with energy absorption reaching 47.1 kJ,which is 2.8 times that of the PR bolt.Furthermore,the necking ratio was significantly reduced,indicating more distributed plastic deformation and delayed failure.Field applications verified the superior performance,resulting in a 27.4%reduction in roof settlement and enhanced structural integrity.These findings confirm that NPR bolts possess excellent shear resistance,energy absorption,and deformation adaptability,and optimizing prestress significantly enhances their support performance,providing a strong basis for geotechnical engineering applications. 展开更多
关键词 npr bolt Jointed rock mass Prestressed force Shear test Shear performance
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Research on tissue section negative detection algorithm based on multispectral microscopic imaging
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作者 Cheng Wang Qian-Qian Ge +7 位作者 Ru-Juan Wu Hao-Pu Jian Hao Chu Jia-Yi Yang Qi Chen Xiao-Qing Zhao Hua-Zhong Xiang Da-wei Zhang 《Journal of Innovative Optical Health Sciences》 2026年第2期141-158,共18页
In recent years,the rapid advancement of artificial intelligence(AI)technology has enabled AI-assisted negative screening to significantly enhance physicians'efficiency through image feature analysis and multimoda... In recent years,the rapid advancement of artificial intelligence(AI)technology has enabled AI-assisted negative screening to significantly enhance physicians'efficiency through image feature analysis and multimodal data modeling,allowing them to focus more on diagnosing positive cases.Meanwhile,multispectral imaging(MSI)integrates spectral and spatial resolution to capture subtle tissue features invisible to the human eye,providing high-resolution data support for pathological analysis.Combining AI technology with MSI and employing quantitative methods to analyze multiband biomarkers(such as absorbance differences in keratin pearls)can effectively improve diagnostic specificity and reduce subjective errors in manual slide interpretation.To address the challenge of identifying negative tissue sections,we developed a discrimination algorithm powered by MSI.We demonstrated its efficacy using cutaneous squamous cell carcinoma(cSCC)as a representative case study.The algorithm achieved 100%accuracy in excluding negative cases and effectively mitigated the false-positive problem caused by cSCC heterogeneity.We constructed a multispectral image(MSI)dataset acquired at 520 nm,600 nm,and 630 nm wavelengths.Subsequently,we employed an optimized MobileViT model for tissue classification and performed comparative analyses against other models.The experimental results showed that our optimized MobileViT model achieved superior performance in identifying negative tissue sections,with a perfect accuracy rate of 100%.Thus,our results confirm the feasibility of integrating MSI with AI to exclude negative cases with perfect accuracy,offering a novel solution to alleviate the workload of pathologists. 展开更多
关键词 Multispectral imaging artificial intelligence cSCC negative detection.
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Correlation between life satisfaction,pleasure level,and negative emotion in patients with chronic renal failure
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作者 Lin-Lin Zhang You-Li Zhang +3 位作者 Ting Liu Jian Wang Chen Chen Xiao-Yu Wang 《World Journal of Psychiatry》 2026年第1期291-298,共8页
BACKGROUND Anxiety,depression,and other negative emotions are common among patients with chronic renal failure(CRF).Analyzing the factors related to negative emotions is necessary to provide targeted nursing care.AIM ... BACKGROUND Anxiety,depression,and other negative emotions are common among patients with chronic renal failure(CRF).Analyzing the factors related to negative emotions is necessary to provide targeted nursing care.AIM To explore the correlations among life satisfaction,pleasure levels,and negative emotions in patients with CRF.METHODS One hundred patients with CRF who received therapy at the First Affiliated Hospital of Jinzhou Medical University between December 2022 and February 2025 were included.The Depression,Anxiety,and Stress Scale(DASS-21),Satisfaction with Life Scale(SWLS),and Temporal Experience of Pleasure Scale(TEPS)were used to evaluate negative emotions,life satisfaction,and pleasure level,respectively.Pearson’s correlation coefficient analyzed the correlation between life satisfaction,pleasure level,and negative emotions.Linear regression analysis identified the factors affecting negative emotions.RESULTS The average DASS-21 score among patients with CRF was 51.90±2.30,with subscale scores of 17.90±1.50 for depression,18.53±1.18 for anxiety,and 15.47±2.36 for stress,all significantly higher than the domestic norm(P<0.05).The average SWLS score was 22.17±4.90.Correlation analysis revealed a negative correlation between the SWLS and total DASS-21 scores(P<0.05),but not with the individual depression,anxiety,or stress dimensions.The average TEPS score was 67.80±8.34.TEPS scores were negatively correlated with the DASS-21 score and the stress dimension(P<0.05),but not with depression or anxiety.Linear regression analysis showed that TEPS scores significantly influenced DASS-21 scores(P<0.05).CONCLUSION Patients with CRF experience high levels of negative emotions,which are negatively correlated with life satisfaction and pleasure.Furthermore,pleasure level had an impact on negative emotions. 展开更多
关键词 Chronic renal failure HEMODIALYSIS negative emotion Life satisfaction PLEASURE CORRELATION
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Experimental and Numerical Analysis on Mechanical Behaviors of Negative Poisson’s Ratio Metamaterials
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作者 Zeyu Han Chengbei He Liang Wang 《Computer Modeling in Engineering & Sciences》 2026年第2期234-252,共19页
Negative Poisson’s ratio materials and structures exhibit lateral expansion under tensile loading,demonstrating significant mechanical advantages over conventional materials.This study systematically investigated thr... Negative Poisson’s ratio materials and structures exhibit lateral expansion under tensile loading,demonstrating significant mechanical advantages over conventional materials.This study systematically investigated three typical two-dimensional negative Poisson’s ratio metamaterial structures(Concave honeycomb,Anti-chiral,and Anti-chiral concave honeycomb hybrid structures)through both experimental tests and numerical analysis.The test specimens were fabricated using selective laser melting(SLM)additive manufacturing technology,and the experimental test was conducted with the use of a DIC strain measurement system.The numerical studies were performed considering both static tensile loading and dynamic impact loading with different strain rates.The deformation behaviors,failure process,negative Poisson’s ratio effects,and energy absorption capacity of the three different metamaterial structures are systematically investigated,and the associated mechanical mechanisms are thoroughly revealed.Results and findings of this work could provide valuable guidance for the engineering design and application of negative Poisson’s ratio metamaterials and structures. 展开更多
关键词 negative Poisson’s ratio METAMATERIALS energy absorption failure mechanisms
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西瓜NPR基因家族的鉴定及其在盐胁迫下的表达分析 被引量:1
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作者 贾云鹤 《中国瓜菜》 北大核心 2025年第1期16-24,共9页
以拟南芥NPR基因家族成员蛋白序列为查询序列,在西瓜基因组数据库中鉴定西瓜NPR基因家族成员,并对其进行生物信息学分析及盐胁迫下的表达分析。共鉴定到4个成员,将其命名为ClNPR1~ClNPR4,其编码蛋白的理化性质、保守功能结构域、重要氨... 以拟南芥NPR基因家族成员蛋白序列为查询序列,在西瓜基因组数据库中鉴定西瓜NPR基因家族成员,并对其进行生物信息学分析及盐胁迫下的表达分析。共鉴定到4个成员,将其命名为ClNPR1~ClNPR4,其编码蛋白的理化性质、保守功能结构域、重要氨基酸残基及motif分析结果与其他物种有较高的一致性,顺式作用元件分析显示,ClNPRs与非生物胁迫相关。300 mmol·L^(-1)NaCl处理耐盐材料和盐敏感材料,分别取盐胁迫0、8、24 h的叶片进行4个NPR基因的表达模式分析,结果表明,ClNPR1在盐敏感和耐盐材料中都显著上调表达,但盐胁迫24 h,ClNPR1在盐敏感材料中显著下调表达,在耐盐材料中虽然下调但还保持较高的表达水平,且在耐盐材料中的表达量显著高于盐敏感材料;盐胁迫24 h,ClNPR2和ClNPR3在盐敏感和耐盐材料中都显著上调表达,在耐盐材料中的表达量均显著高于盐敏感材料。推测ClNPRs基因在西瓜响应盐胁迫的过程中扮演重要角色。 展开更多
关键词 西瓜 npr家族蛋白 盐胁迫 表达
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峰前循环荷载作用下NPR锚杆锚固结构面抗剪强度特性研究 被引量:1
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作者 陶志刚 张腾伍 +1 位作者 洪陈杰 张海江 《金属矿山》 北大核心 2025年第9期78-87,共10页
NPR锚杆锚固结构面在静态剪切荷载作用下表现出超常抗剪性能,然而在动态循环荷载作用下的力学响应尚需进一步验证。采用经加工的原岩试样,进行均质砂岩结构面的峰前循环加载剪切试验,对比分析无锚固和NPR锚杆锚固2种工况下循环加载次数... NPR锚杆锚固结构面在静态剪切荷载作用下表现出超常抗剪性能,然而在动态循环荷载作用下的力学响应尚需进一步验证。采用经加工的原岩试样,进行均质砂岩结构面的峰前循环加载剪切试验,对比分析无锚固和NPR锚杆锚固2种工况下循环加载次数、加载速率、不同幅值等因素对结构面剪切强度的影响规律。结果表明:①循环次数为80次时,无锚固结构面的抗剪强度达到峰值;相比之下,NPR锚杆锚固结构面的峰值抗剪强度明显提升。②循环加载速率由1 kN/s增大至1.5 kN/s时,无锚固结构面抗剪强度下降较快;与此相反,NPR锚杆锚固结构面在加载速率增大时,峰值抗剪强度呈现更大的提升幅度。③循环加载幅值由50%τ_(max)增大至80%τ_(max),无锚固结构面抗剪强度降低;而NPR锚杆锚固结构面的抗剪强度增大,有效改善了未锚固结构面的脆性破坏特征。④不同法向应力下,NPR锚杆锚固结构面的抗剪强度均比无锚固结构面得到显著提升。上述研究结果可为露天矿开采的抗震和防爆设计提供科学依据。 展开更多
关键词 峰前循环加载 锚固剪切试验 岩体结构面 npr 锚杆
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不同锚固孔径下2G-NPR锚杆锚固特性试验研究 被引量:1
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作者 陶志刚 李梦楠 +2 位作者 于海军 范方政 王炯 《岩土力学》 北大核心 2025年第S1期67-80,共14页
为了更好地分析2G-NPR锚杆锚固特性,确定合理的锚杆直径与锚固孔径的匹配范围。以室内拉拔试验为基础,分析了不同锚固孔径下锚固体系破坏形式;建立了锚固体与锚固孔径匹配的力学模型,推导了沿锚固方向轴向力和界面剪应力理论计算公式;... 为了更好地分析2G-NPR锚杆锚固特性,确定合理的锚杆直径与锚固孔径的匹配范围。以室内拉拔试验为基础,分析了不同锚固孔径下锚固体系破坏形式;建立了锚固体与锚固孔径匹配的力学模型,推导了沿锚固方向轴向力和界面剪应力理论计算公式;通过有限差分程序FLAC3D建立不同锚固孔径下的拉拔模型,揭示了锚固系统的应力分布规律。结果表明:(1)在不同锚固孔径下,以直径匹配差值8 mm为界,锚固体系在达到最大承载能力时的破坏界面不同;(2)锚固体系在加载时荷载-位移曲线可分为预加载、弹性变形、塑性变形、界面开始脱黏、界面完全脱黏5个阶段;(3)拉拔力为30 kN条件下,随着锚固孔径增大,锚杆-锚固剂界面剪应力分布随孔径变化不大,但在螺旋状肋处有明显剪应力集中现象,相同位置锚杆-锚固剂界面剪应力是锚固剂-围岩界面剪应力的2~3倍,锚固剂-围岩界面剪应力分布随孔径增大而明显减小;(4)确定了直径为18 mm的2G-NPR锚杆最佳锚固孔径差值范围为8~12 mm。 展开更多
关键词 拉拔试验 2G-npr锚杆 锚固孔径 锚固性能 锚固失效形式
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拉伸荷载条件下新型NPR锚杆韧性材料宏观变形特征分析
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作者 陶志刚 隋麒儒 +3 位作者 丰于翔 孟志刚 姚旭龙 何满潮 《绿色矿山》 2025年第1期44-50,共7页
岩土工程在受到复杂地质条件的综合作用时极易产生大变形灾害响应,传统金属支护材料因不能够忍受大变形而发生失效破坏现象。为应对大变形灾害,研发了新型NPR锚杆韧性材料(Negative Poisson’s Ratiobolt)。为了探索新型NPR锚杆韧性材... 岩土工程在受到复杂地质条件的综合作用时极易产生大变形灾害响应,传统金属支护材料因不能够忍受大变形而发生失效破坏现象。为应对大变形灾害,研发了新型NPR锚杆韧性材料(Negative Poisson’s Ratiobolt)。为了探索新型NPR锚杆韧性材料的宏观变形特征,开展了NPR锚杆室内拉伸对比试验。采用NPR锚杆专用试验机,并利用相机进行全过程变形特征记录。结果发现:NPR锚杆具有更好的均匀变形特性,且在拉伸变形失效全过程早期阶段就开始发生均匀变形;对不同钢筋进行失效断口分类:主要分为“分层型断口”和“纤维-基体之间的界面破坏类断裂型断口”;通过力学机制分析NPR锚杆均匀变形特性及颈缩现象不显著的原因:发现NPR钢在拉伸变形失效后的颈缩处曲率半径更大,使其颈缩现象不明显,这是由于其最大均匀应变与最大应变差值相对较小所致;通过LS-DYNA算法对螺纹肋结构和光圆结构对于钢筋变形的影响进行数值模拟分析,结果证明螺纹肋结构使得钢筋在拉伸过程中能够更好地均匀变形,吸收变形能。综上所.述,通过对新型NPR锚杆韧性材料的变形特征的宏观分析,有助于更好地揭示其静力拉伸性能,为准静态工程实践提供了有价值的参考。 展开更多
关键词 韧性材料 npr锚杆 拉伸试验 变形特征 宏观分析
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Negative Poisson's ratio and peripheral strain of an NPR anchor cable 被引量:3
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作者 TAO Zhi-gang XU Hao-tian +3 位作者 REN Shu-lin GUO Long-ji QIN Ke ZHU Yi-fei 《Journal of Mountain Science》 SCIE CSCD 2022年第8期2435-2448,共14页
Materials with a negative Poisson’s ratio effect perform significantly better than traditional materials for rock mass impact resistance,shear resistance,and energy absorption.Based on these advantages,a negative Poi... Materials with a negative Poisson’s ratio effect perform significantly better than traditional materials for rock mass impact resistance,shear resistance,and energy absorption.Based on these advantages,a negative Poisson’s ratio anchor cable(NPR anchor cable)with high elongation and constant resistance was developed and successfully applied in the field of mine disaster control.However,theoretical and experimental research on the negative Poisson’s ratio effect and peripheral strain characteristics of NPR anchor cables is currently incomplete.This study used several theories and methods,such as static tensile,peripheral strain measurement,and static negative Poisson’s ratio measurement,to investigate the radial deformation law of an NPR anchor cable and the negative Poisson’s ratio characteristics.Experimental results elucidated constant resistance changes in an NPR anchor cable during operation,the motion of the constant resistance body in the constant resistance sleeve,and the deformation law of the constant resistance sleeve.Negative Poisson’s ratio characteristics of the NPR anchor cable and its superior energy absorption characteristics were verified and it provided a theoretical and experimental basis for energy absorption mechanisms of an NPR anchor cable. 展开更多
关键词 npr anchor cable Static tensile test negative Poisson’s ratio Energy absorption
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基于恒阻装置尺寸设计的NPR锚索力学性能优化研究
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作者 朱淳 徐佳俊 +4 位作者 何满潮 谭毅 陈佳敏 李海波 陈兵兵 《中南大学学报(自然科学版)》 北大核心 2025年第3期1113-1124,共12页
NPR锚索(恒阻大变形锚索)已广泛应用于采矿、水利、交通等工程领域,为适应深部工程复杂的地质条件,需适当调整NPR锚索的尺寸,以提高NPR锚索的力学性能,为此,本文开展了恒阻装置几何尺寸的设计参数对NPR锚索静/动力学性能的影响规律研究... NPR锚索(恒阻大变形锚索)已广泛应用于采矿、水利、交通等工程领域,为适应深部工程复杂的地质条件,需适当调整NPR锚索的尺寸,以提高NPR锚索的力学性能,为此,本文开展了恒阻装置几何尺寸的设计参数对NPR锚索静/动力学性能的影响规律研究。首先,使用ABAQUS有限元软件建立NPR锚索的静/动力仿真数值模型,并基于室内力学试验结果对其精准性进行验证。其次,采用正交试验法制定恒阻装置尺寸参数数值模拟方案,对不同尺寸参数下NPR锚索的静力拉伸和动力冲击参数进行模拟试验。最后,通过极差分析确定恒阻装置各尺寸参数对于NPR锚索力学性能的影响程度。研究结果表明,NPR锚索恒阻装置各尺寸在静力拉伸试验中对恒阻力值及其波动程度的影响程度排序与在动力冲击试验中对冲击阻力和能量吸收率的影响程度排序一致,影响程度排序由大到小依次为恒阻体后端直径、恒阻套筒厚度、恒阻体长度、恒阻体平台厚度。试验结果可为NPR锚索恒阻装置的优化设计提供参考。 展开更多
关键词 npr锚索 静/动力学性能 ABAQUS 正交试验 参数优化
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不同裂隙倾角NPR锚固岩体力学特性对比研究
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作者 缪澄宇 崔力 +2 位作者 孙晓明 谭雨泽 李志虎 《采矿与安全工程学报》 北大核心 2025年第4期779-788,共10页
裂隙岩体锚固力学特性是围岩支护设计的基本依据。针对新型负泊松比锚索(NPR)的支护效能,通过相似物理模型实验,对比研究不同预制裂隙倾角下NPR锚固体与普通(PR)锚固体力学特性差异,分析锚固体强度特性、变形破坏特性和声发射特性。随... 裂隙岩体锚固力学特性是围岩支护设计的基本依据。针对新型负泊松比锚索(NPR)的支护效能,通过相似物理模型实验,对比研究不同预制裂隙倾角下NPR锚固体与普通(PR)锚固体力学特性差异,分析锚固体强度特性、变形破坏特性和声发射特性。随着裂隙倾角的增大,锚固体应力-应变曲线形态由双峰值逐渐向单峰值演变,锚固体弹性模量先增大后减小,峰值强度不断增大,NPR锚固体弹性模量和强度均明显高于PR锚固体。考虑岩体峰值强度时,NPR锚索最佳支护倾角为60°~90°,而PR锚索仅在支护倾角90°时达到最优支护效果。2类锚固体均呈现拉剪复合破坏特征,但NPR锚索未破断,锚固体完整性好,而PR锚索发生破断,锚固体完整性差。NPR和PR锚固体内部分别在预制裂隙倾角为75°和45°之前产生剪切破坏,超过此角度后则转变为张拉破坏。NPR锚固体自由面变形小且较为均匀,局部位移差较小,而PR锚固体自由面变形较大且不均匀,局部位移差较大。声发射特征显示,由于NPR锚索的持久约束作用,锚固体振铃计数更为均匀,而PR锚固体振铃计数较大值则集中在应变初期锚索破断时刻。 展开更多
关键词 npr锚索 锚固体 相似实验 双轴压缩 力学特性
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桥梁NPR钢圈-橡胶复合减隔震支座承载力特性研究
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作者 刘爱霞 马龙飞 +1 位作者 王占飞 赵中华 《北方交通》 2025年第11期1-6,共6页
为避免地震中桥梁落梁,基于位移控制及橡胶减震机理,提出负泊松比钢圈-橡胶(NSR-RB)支座。通过精细化数值分析,得到NSR-RB在水平往复荷载作用下的滞回曲线和骨架曲线,并进一步分析了各组成构件的抗剪刚度、极限承载力和耗能占比。结果表... 为避免地震中桥梁落梁,基于位移控制及橡胶减震机理,提出负泊松比钢圈-橡胶(NSR-RB)支座。通过精细化数值分析,得到NSR-RB在水平往复荷载作用下的滞回曲线和骨架曲线,并进一步分析了各组成构件的抗剪刚度、极限承载力和耗能占比。结果表明,NSR-RB支座的初期刚度与传统橡胶支座相同,随着荷载位移的增大,NSR-RB支座的抗剪刚度逐渐增大,NPR钢圈的耗能占比也逐渐提升至75.8%。与传统橡胶支座相比,NSR-RB的极限承载力提升了262.6%。因此,当水平位移较小时,NSR-RB支座能够充分发挥橡胶支座延长结构自振周期的作用;当水平位移较大时,NPR钢圈能够显著改善支座整体水平侧向承载能力和耗能能力,从而防止落梁。 展开更多
关键词 结构减震 橡胶支座 npr钢圈 数值分析 力学性能
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外周血WBC、NPR、PLR在成人肺炎中的变化特征及其对病情评估和预后预测的价值
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作者 冯珊珊 孙静 +4 位作者 左芳 耿新普 盛丽丽 刘荣 赵峰 《分子诊断与治疗杂志》 2025年第12期2322-2324,2328,共4页
目的探究外周血白细胞计数(WBC)、中性粒细胞与血小板计数比值(NPR)、血小板与淋巴细胞比值(PLR)在成人肺炎中的变化特征及其对病情评估和预后预测的价值。方法将2022年1月至2025年1月南京医科大学康达学院附属涟水人民医院收治的104例... 目的探究外周血白细胞计数(WBC)、中性粒细胞与血小板计数比值(NPR)、血小板与淋巴细胞比值(PLR)在成人肺炎中的变化特征及其对病情评估和预后预测的价值。方法将2022年1月至2025年1月南京医科大学康达学院附属涟水人民医院收治的104例成人社区获得性肺炎患者纳入研究。根据患者的肺炎严重指数(PSI)分为低危组(66例,PSI≤90分)和高危组(38例,PSI>90分),再根据患者预后效果分为预后良好组(78例)和预后不良组(26例),比较不同病情严重程度及不同预后患者的外周血WBC、NPR、PLR水平,分析外周血指标与病情及预后的关系,使用ROC分析外周血指标对预后的预测价值,使用Logistic回归分析影响患者预后的危险因素。结果高危组外周血WBC、NPR、PLR均高于低危组,差异有统计学意义(P<0.05);经Spearman分析,外周血WBC、NPR、PLR与病情严重程度呈正相关性(P<0.05);预后不良组患者的外周血WBC、NPR、PLR水平均高于预后良好组,差异有统计学意义(P<0.05);经ROC分析,外周血WBC、NPR、PLR及联合检测对患者预后预测的曲线下面积分别为0.805、0.802、0.831、0.908(P<0.05),Logistic回归分析显示,外周血WBC≥13.08×10^(9)/L、NPR≥3.2、PLR≥175.60是影响成人社区获得性肺炎患者预后的危险因素(P<0.05)。结论外周血WBC、NPR、PLR水平会随成人肺炎患者病情加重而升高,可作为临床评估预后的辅助检测指标。 展开更多
关键词 社区获得性肺炎 白细胞计数 中性粒细胞与血小板计数比值 血小板与淋巴细胞比值
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3例NPR2基因变异相关矮小症临床分析及3种变异体外功能验证
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作者 张淑颖 连群 +2 位作者 蔡丽华 王辰璐 许珊珊 《罕少疾病杂志》 2025年第9期1-4,共4页
目的 厦门大学附属第一医院发现3例NPR2基因变异伴骨骼畸形的矮小患儿,拟通过国内外文献报道、生信分析及体外功能验证,对NPR2基因变异所致矮小患者的临床表现、治疗及可能致病的机制进行分析。方法 通过医院HIS系统对患者的临床资料进... 目的 厦门大学附属第一医院发现3例NPR2基因变异伴骨骼畸形的矮小患儿,拟通过国内外文献报道、生信分析及体外功能验证,对NPR2基因变异所致矮小患者的临床表现、治疗及可能致病的机制进行分析。方法 通过医院HIS系统对患者的临床资料进行收集汇总。对NPR2基因变异体进行软件功能预测。用慢病毒转染293T细胞构建野生型及3种变异型稳定转染细胞。用酶联免疫分析方法测定cGMP水平。用蛋白印迹方法测定NPRB蛋白表达量。结果 报道了2位携带NPR2基因p.R787W杂合变异的特发性矮小患者及1位NPR2基因p.E906G及p.R976H复合杂合变异的Maroteaux型肢端肢中发育不全(AMDM)患者,该2种变异均为新变异,尚未被文献报道。3名患者由不同程度的骨骼畸形。体外功能验证结果:与野生型细胞相比,3种变异型细胞c GMP水平均下降,差异具有统计学意义,其NPRB蛋白表达量无统计学差异。结论 对严重身材矮小且伴有骨骼畸形的患者,应进行基因检测寻找其遗传病因。NPR2基因变异导致矮小的机制尚不明确,仍需进一步探索。 展开更多
关键词 npr2基因 nprB蛋白 基因变异 身材矮小 Maroteaux型肢端肢中发育不全 特发性矮小
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穿越断裂带隧道变形机制及NPR支护数值模拟研究
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作者 曹振生 徐海斌 +2 位作者 虎晓敏 张光逵 刘珂源 《地下空间与工程学报》 北大核心 2025年第6期2122-2132,共11页
穿越断裂带的隧道在铁路工程、水利工程、公路工程较为常见,由穿越断层破碎带所诱发的工程地质灾害占我国隧道灾害总数的50%以上,保证穿断层带隧道的安全稳定是发展我国隧道工程的重中之重。以他白依隧道为工程背景,探究围岩在断层破碎... 穿越断裂带的隧道在铁路工程、水利工程、公路工程较为常见,由穿越断层破碎带所诱发的工程地质灾害占我国隧道灾害总数的50%以上,保证穿断层带隧道的安全稳定是发展我国隧道工程的重中之重。以他白依隧道为工程背景,探究围岩在断层破碎带影响下的有效支护措施。为解决他白依隧道软岩大变形问题,本文首先通过开展现场点荷载试验、地应力试验及室内矿物成分分析试验来探究形成大变形原因的主控因素,之后针对他白依隧道变形力学机制提出高预紧力长短NPR锚网支护方案,依据开挖补偿理论利用NPR锚索的高预紧力对隧道围岩进行应力补偿,并通过数值模拟与现场监测说明隧道在高预紧力长短NPR锚网支护方案下能够有效减少围岩在断层破碎带影响下产生的大变形。该研究成果可为穿越断层带的隧道支护提供参考。 展开更多
关键词 隧道工程 断层破碎带 变形力学机制 npr锚网支护 数值模拟
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Roof deformation of the Beishan Rock Carvings with negative Poisson's ratio anchor support under varied precipitation conditions 被引量:1
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作者 YANG Peixi TAO Zhigang +1 位作者 YANG Xiaojie LI Xiaodan 《Journal of Mountain Science》 2025年第8期3078-3091,共14页
Beishan Rock Carvings in Chongqing,a renowned cultural heritage site in China,flourished during the Tang and Song dynasties and are often referred to as the“Stone Carving Art Museum of the Tang and Song Dynasties.”C... Beishan Rock Carvings in Chongqing,a renowned cultural heritage site in China,flourished during the Tang and Song dynasties and are often referred to as the“Stone Carving Art Museum of the Tang and Song Dynasties.”Cave 168 is a key component of the Beishan Rock Carvings.At present,several through-going cracks have developed in the roof of Cave 168,severely compromising the structural stability of the grotto.The early internal steel plate supports have suffered severe corrosion and can no longer provide effective reinforcement.In addition,the presence of steel columns obstructs visitor access and negatively affects the viewing experience.A new reinforcement method is urgently needed.Therefore,studying the deformation patterns of the structure is of critical importance.This study analyzes the stratigraphic parameters and fracture distribution of Cave 168,considering key influencing factors such as rainfall,self-weight,and the overlying Quaternary soil.On-site monitoring and physical model experiments were conducted to evaluate the changes in roof crack width and displacement before and after reinforcement with negative Poisson's ratio(NPR)anchor cables.The results reveal that the roof of Cave 168 contains several through-going cracks and numerous microcracks,which serve as infiltration channels for surface water.These accelerate the softening of the mudstone and pose a significant threat to the cave's structural safety.During the experiment,the main change in the crack exhibited a“semi-archshaped”propagation pattern.In the first ten minutes,as the rock transitioned from dry to moist conditions,a slight crack closure was observed.As rainfall continued,crack propagation accelerated.After rainfall ceased,crack width remained stable over a short period.Under NPR anchor support,the influence of rainfall on roof settlement was effectively mitigated,ensuring the safety and stability of the roof.The NPR anchors successfully limited the roof settlement to within 0.3 mm and provided effective control over both total and differential settlement.These findings offer valuable insights into the application of NPR anchor cables in the conservation of grotto heritage structures. 展开更多
关键词 Grotto stability Physical model experiment RAINFALL npr anchor(cable) On-site monitoring
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Elderly care needs and factors influencing negative emotions among first-generation only child parents in a Chinese city 被引量:1
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作者 Rui Dong Xiu-Xia Wang Ling-Juan Zhang 《World Journal of Psychiatry》 2025年第5期155-163,共9页
BACKGROUND China has recently encountered severe challenges associated with population aging.Parents of first-generation only children face significant challenges regarding elderly care needs and the associated negati... BACKGROUND China has recently encountered severe challenges associated with population aging.Parents of first-generation only children face significant challenges regarding elderly care needs and the associated negative emotions.AIM To analyze the elderly care needs of first-generation only child parents in China and identify factors that influence negative emotions.METHODS This study used a cross-sectional design.Convenience sampling was used to select 1580 elderly individuals who met the inclusion criteria in a Chinese city between June and September 2022.A questionnaire was administered to collect general information about participants.Depression and anxiety were assessed using the patient health questionnaire-9 and generalized anxiety disorder-7 scale,respectively.A logistic regression analysis was performed to evaluate the relevant correlations.RESULTS Among 1580 first-generation only child parents,1120(70.89%)preferred family based care,324(20.51%)opted for community care,and 136(8.61%)chose institutional care,with 460(29.11%)reporting negative emotions.Significant differences in the distribution of negative emotions among only child parents were observed based on age,marital status,living conditions,disability,type of chronic disease,frailty status,and family support(P<0.05).The regression analysis indicated that disability,type of chronic disease,living environment,frailty status,and level of family support were independent risk factors for negative emotions among parents with only children(P<0.05).CONCLUSION Elderly care for parents of only children is primarily family-based.Independent risk factors for negative emotions in this group include disability,chronic disease type,and living environment. 展开更多
关键词 AGING First generation Only child Elderly care needs negative emotions Influencing factors
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Important role of tumor deposits and negative lymph nodes in prognosis of N1c colorectal cancer patients 被引量:1
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作者 Zhi-Gang Sun Shao-Xuan Chen +11 位作者 Bai-Long Sun Da-Kui Zhang Ding-Rong Zhong Tong-Yin Zhang Yu-Wan Hu Zi-Han Han Wen-Xiao Wu Zhi-Yong Hou Li Yao Ya-Jun Zhang Hong-Liang Sun Jian-Zheng Jie 《World Journal of Gastroenterology》 2025年第31期52-62,共11页
BACKGROUND The number of tumor deposits(TDs)does not play a part in the current tumor node metastasis staging.Negative lymph node(NLN)status is associated with the prognosis of colorectal cancer(CRC),but its clear rol... BACKGROUND The number of tumor deposits(TDs)does not play a part in the current tumor node metastasis staging.Negative lymph node(NLN)status is associated with the prognosis of colorectal cancer(CRC),but its clear role in N1c stage remains to be defined.AIM To evaluate the combination of TDs and NLNs as potential prognostic indicators in N1c CRC.METHODS We retrospectively identified 107 consecutive patients who had N1c CRC radically resected at China-Japan Friendship Hospital.The combination of TDs and NLNs was calculated by the formula NLNTD=NLN/(TD+1).Cutoff values of NLNs and NLNTD were determined using the R package“survminer”.Disease-free survival(DFS),overall survival(OS)and cancer-specific survival(CSS)were determined using the Kaplan-Meier method to assess the impact of NLNTD on prognosis.Results were compared using the log-rank test.RESULTS The median follow-up time was 63.17(45.33-81.37)months for DFS,with 33.64%(36/107)of patients experiencing recurrence during follow-up.Five-year DFS was 66.0%(57.3%-76.0%).There was no significant difference in prognosis between patients with>12 and≤12 NLNs(P=0.058)for DFS.Similar results were seen according to the number of TDs.The definition of NLNTD=NLN/(TD+1)with a cutoff value of 6 divided patients into two groups with different DFS(P=0.005).Five-year DFS for patients with NLNTD>6 was 73.5%(63.6%-85.0%),compared with 50.0%(35.7%-70.0%)for those with NLNTD≤6.These two groups had different prognosis without perineural invasion(P=0.012)or lymphovascular invasion(P=0.002)even neither(P=0.053).Similar results were seen for OS and CSS.CONCLUSION NLNTD could serve as important prognostic factor for outcomes in N1c CRC patients.These patients could be stratified for prognosis through NLNTD and the high-risk should be given more attention during treatment. 展开更多
关键词 Colorectal cancer N1c stage negative lymph node Tumor deposits PROGNOSIS
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