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螺旋外观NPR锚杆预应力锚固体系工作机理研究
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作者 杨军 詹家旺 +2 位作者 边文辉 王科学 董美强 《中国公路学报》 北大核心 2026年第2期202-214,共13页
螺旋外观的锚杆通常配合树脂黏结剂和机械式锚具进行使用,由于其可施加高预应力、锚固效率高等优势,逐渐被应用在高强度、高延伸率的锚杆设计中,目前关于机械式锚具和螺旋外观锚杆的锚固机理研究较少。基于一种高抗拉强度(950 MPa)、高... 螺旋外观的锚杆通常配合树脂黏结剂和机械式锚具进行使用,由于其可施加高预应力、锚固效率高等优势,逐渐被应用在高强度、高延伸率的锚杆设计中,目前关于机械式锚具和螺旋外观锚杆的锚固机理研究较少。基于一种高抗拉强度(950 MPa)、高延伸率(30%)的螺旋外观NPR锚杆,使用力学解析、数值模拟和试验的方式,对机械式锚具预应力施加机理、使用机械式锚具时锚杆的荷载传递以及使用树脂黏结时的黏结机理进行了分析研究。结果表明:使用机械式锚具配合前卡式千斤顶和限位板可有效地对NPR锚杆施加100kN的预紧力;在锚具作用区,锚杆表面峰值米塞斯应力出现在离加载段较近的位置,高于拉伸强度约50MPa。静力拉伸试验表明锚固效率大于95%。相比常见的矿用锚杆,螺旋肋NPR锚杆具有更好的树脂黏结性能,原因在于螺旋肋的外观设计为肋与树脂之间提供更大的接触面积,在20mm直径、1mm肋高的条件下,NPR锚杆黏结强度是左旋锚杆的1.28倍,肋与树脂的有效接触面积是1.30倍。 展开更多
关键词 隧道工程 锚固体系 力学解析 npr锚杆 预应力支护
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NPR锚固砂岩冲击动力学特性试验
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作者 王炯 姜健 +5 位作者 王思语 涂婕 常译文 马磊 王旭 罗爱忠 《煤炭科学技术》 北大核心 2026年第2期207-219,共13页
以砂岩为研究对象,设计制备了具有恒阻特性的模型NPR锚索,通过霍普金森杆(Split Hopkinson Pressure Bar)冲击试验探究锚固岩体冲击动力学特性。基于SHPB试验系统,分别对无锚砂岩、PR锚固砂岩及NPR锚固砂岩试件,在0.26、0.28、0.30 MPa... 以砂岩为研究对象,设计制备了具有恒阻特性的模型NPR锚索,通过霍普金森杆(Split Hopkinson Pressure Bar)冲击试验探究锚固岩体冲击动力学特性。基于SHPB试验系统,分别对无锚砂岩、PR锚固砂岩及NPR锚固砂岩试件,在0.26、0.28、0.30 MPa三种冲击气压下开展动态加载试验,系统对比不同试件的动态力学响应特征、能量传递规律、锚索受力过程及变形破坏特征。结果表明:3类试件的动态抗压强度与峰值应变均呈现显著应变率效应,其中NPR锚固砂岩的动态抗压强度始终高于PR锚索锚固砂岩与无锚砂岩,且峰值应变保持最低水平,表明NPR锚索可通过实时调节支护阻力优化岩体强度;能量分布方面,NPR锚固砂岩的透射能、破碎耗散能及耗散能密度均为最低,其滑移变形机制有效延缓了冲击载荷引发的岩体破裂进程;对比锚索受力过程发现,NPR锚索在冲击载荷下呈现锯齿状波动调节特性,全程未发生断裂失效,相较于PR锚索的脆性破裂具有显著优势;破坏形态对比表明,NPR锚固砂岩仅出现边缘局部崩落,少量大片状岩块剥脱,主体保持长圆柱状结构,破坏形式以张拉破坏为主,而无锚砂岩和PR锚固砂岩均存在较大范围的剪切破坏,破碎程度更重,证实了NPR锚索对张性裂纹扩展的抑制作用。综合试验数据可见,NPR锚索通过增强岩体强度储备、调控能量耗散路径与抑制裂纹扩展速率的三重协同机制,显著提升岩体动态抗冲击性能,为冲击地压防治提供了新的技术路径。 展开更多
关键词 锚固砂岩 npr锚索 SHPB冲击 动态抗压强度 能量传递
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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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粉葛NPR1蛋白的生物信息学分析
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作者 黄俊文 黄小寒 +4 位作者 黎兴 黄竹韵 司茹兰 戴超 吴少平 《肇庆学院学报》 2026年第2期1-6,共6页
病原物的侵袭严重干扰了植物正常的生长发育,病害已是农业健康发展的威胁之一.NPR1(NONEXPRESSER of PR GENES 1)是植物免疫应答的核心调控因子,其赋予了植物对病害的抗性.本研究在粉葛基因组中发现了一个NPR1基因,并对PmNPR1因子进行... 病原物的侵袭严重干扰了植物正常的生长发育,病害已是农业健康发展的威胁之一.NPR1(NONEXPRESSER of PR GENES 1)是植物免疫应答的核心调控因子,其赋予了植物对病害的抗性.本研究在粉葛基因组中发现了一个NPR1基因,并对PmNPR1因子进行了综合分析.PmNPR1基因包含4个外显子和3个内含子,编码的蛋白质的等电点为5.65,分子式为C2761H4457N773O851S27,归一化后的溶解度为0.427,为亲水性蛋白质.定位分析显示PmNPR1可能定位于细胞之中,具有7个典型的抗原表位,是一个在细胞中可被其他因子所识别协作执行生物学功能蛋白.结构分析发现其为拟南芥AtNPR1的同源物,存在类似结构及可被翻译后修饰的潜力.本研究分析可为后续PmNPR1的功能研究提供线索并为粉葛栽培管理规范化赋能. 展开更多
关键词 粉葛 npr1 生物信息学 分析
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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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Navigating climate change in carbon negative Bhutan:Insights from policy influencers and comparison to the wider Himalayan region
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作者 Tashi DORJI Angus MORRISON-SAUNDERS David BLAKE 《Journal of Mountain Science》 2026年第2期775-797,共23页
Climate change is one of the most pressing global challenges and spares no nation.Bhutan,as the only carbon negative country in the world,is no exception and being in the Himalayas–a region warming faster than the gl... Climate change is one of the most pressing global challenges and spares no nation.Bhutan,as the only carbon negative country in the world,is no exception and being in the Himalayas–a region warming faster than the global average–further intensifies climate risks.This study explores how Bhutan navigates climate change through the perspectives of 41 policy influencers,including politicians,civil servants,and leaders from nongovernment organisations and the media.The findings are compared with scientific literature from the broader Himalayan region to identify shared vulnerabilities(e.g.,glacial lake outburst floods,water scarcity,and agricultural disruptions)and governance challenges(e.g.,financial constraints,geopolitical pressures,and gaps in policy implementation).The study reveals that Bhutan,like its Himalayan neighbours,prioritizes adaptation over mitigation due to immediate climate threats,despite its carbonnegative status.However,Bhutan faces unique pressures in upholding its dual commitments—maintaining 60%forest cover and carbon neutrality—amid competing development needs.While its Gross National Happiness(GNH)framework provides a holistic governance model,the analysis uncovers systemic barriers,including limited financing,transboundary climate risks,and uneven policy execution,which mirror regional struggles.The paper contributes to climate governance discourse by highlighting the risks of symbolic environmental pledges without robust implementation mechanisms,particularly for vulnerable mountain nations.It calls for integrated policies that bridge mitigation and adaptation,stronger regional cooperation,and equitable climate financing.The findings are relevant for policymakers in the Himalayas and international stakeholders advocating context-specific,justiceoriented climate strategies. 展开更多
关键词 BHUTAN Climate change HIMALAYAS Climate governance Carbon negative Climate resilience
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Error Analysis of Geomagnetic Field Reconstruction Model Using Negative Learning for Seismic Anomaly Detection
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作者 Nur Syaiful Afrizal KhairulAdibYusof +5 位作者 Lokman Hakim Muhamad Nurul Shazana Abdul Hamid Mardina Abdullah Mohd Amiruddin Abd Rahman Syamsiah Mashohor Masashi Hayakawa 《Computers, Materials & Continua》 2026年第2期1338-1353,共16页
Detecting geomagnetic anomalies preceding earthquakes is a challenging yet promising area of research that has gained increasing attention in recent years.This study introduces a novel reconstruction-based modeling ap... Detecting geomagnetic anomalies preceding earthquakes is a challenging yet promising area of research that has gained increasing attention in recent years.This study introduces a novel reconstruction-based modeling approach enhanced by negative learning,employing a Bidirectional Long Short-Term Memory(BiLSTM)network explicitly trained to accurately reconstruct non-seismic geomagnetic signals while intentionally amplifying reconstruction errors for seismic signals.By penalizing the model for accurately reconstructing seismic anomalies,the negative learning approach effectively magnifies the differences between normal and anomalous data.This strategic differentiation enhances the sensitivity of the BiLSTM network,enabling improved detection of subtle geomagnetic anomalies that may serve as earthquake precursors.Experimental validation clearly demonstrated statistically significant higher reconstruction errors for seismic signals compared to non-seismic signals,confirmed through the Mann-Whitney U test with a p-value of 0.0035 for Root Mean Square Error(RMSE).These results provide compelling evidence of the enhanced anomaly detection capability achieved through negative learning.Unlike traditional classification-based methods,negative learning explicitly encourages sensitivity to subtle precursor signals embedded within complex geomagnetic data,establishing a robust basis for further development of reliable earthquake prediction methods. 展开更多
关键词 Error analysis geomagnetic field BiLSTM model negative learning earthquake precursor
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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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A novel bHLH transcription factor LlbHLH12 negatively regulates anthocyanin biosynthesis during Lycoris longituba petal development
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作者 Keyi Feng Hongyan Tan +4 位作者 Ling Zhou Tingting Shi Lianggui Wang Yuanzheng Yue Xiulian Yang 《Horticultural Plant Journal》 2026年第3期690-703,共14页
Flower color is an essential trait in ornamental plant breeding. Lycoris longituba is a popular ornamental plant native to central eastern China. The decrease in anthocyanin accumulation causes L. longituba petal colo... Flower color is an essential trait in ornamental plant breeding. Lycoris longituba is a popular ornamental plant native to central eastern China. The decrease in anthocyanin accumulation causes L. longituba petal color fading during flower development, which considerably affects the ornamental value of L. longituba. However, mechanisms underlying anthocyanin biosynthesis inhibition during L. longituba petal development remain unclear. In this study, three LlDFR genes were confirmed to be involved in anthocyanin biosynthesis and LlDFRc exerted the strongest promoting effect on anthocyanin accumulation. According to the correlation analysis results, LlbHLH12 exhibited the strongest negative correlation with LlDFRc. Quantitative real-time PCR analysis showed that LlbHLH12 was highly expressed during the medium bud and full bloom stages of flower development. LlbHLH12 was identified as a member of subgroup XII of bHLH transcription factor family. Subcellular localization and transcriptional activation ability assay revealed that LlbHLH12 was located in the nucleus without transcriptional activation activity. Overexpression of LlbHLH12 in Nicotiana tabacum and L. longituba inhibited anthocyanin accumulation by suppressing the expression of anthocyanin biosynthetic pathway genes. Furthermore, yeast one-hybrid, dual-luciferase, and β-glucuronidase activity assays showed that LlbHLH12 directly bound to the promoters of LlPAL and LlDFRc and suppressed their expression to inhibit anthocyanin biosynthesis. Overall, our study identified a novel bHLH repressor negatively regulating anthocyanin biosynthesis and provided new insights into the molecular mechanisms underlying color fading in L. longituba petals. 展开更多
关键词 Lycoris longituba bHLH transcription factor negative regulation Anthocyanin biosynthesis Flower color
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Mechanisms of Gualou Beimu Yin(瓜蒌贝母饮)in suppressing the development and metastasis of triple-negative breast cancer:an integrated study based on network pharmacology,transcriptomics,and metabolomics
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作者 JIA Ao LIU Shuang +3 位作者 GAO Tingting ZHANG Haoran GAO Wenyuan WU Xiongzhi 《Journal of Traditional Chinese Medicine》 2026年第1期149-159,共11页
OBJECTIVE:To identify the antitumor effects of Gualou Beimu Yin(瓜蒌贝母饮,GLBMY)in triple-negative breast cancer(TNBC)and to explore the underlying mechanisms.METHODS:A mouse model of breast cancer was established an... OBJECTIVE:To identify the antitumor effects of Gualou Beimu Yin(瓜蒌贝母饮,GLBMY)in triple-negative breast cancer(TNBC)and to explore the underlying mechanisms.METHODS:A mouse model of breast cancer was established and treated with GLBMY.Freeze-dried GLBMY powder was used to treat MDA-MB-231 and BT549 cells to assess the therapeutic efficacy of GLBMY against TNBC.Network pharmacology,transcriptomics and metabolomics were employed to identify the potential mechanism of GLBMY in TNBC treatment.Finally,the main regulating genes and proteins in the enriched pathways were validated by Quantitative real-time polymerase chain reaction(q PCR)and Western blotting analysis to confirm its mechanism.RESULTS:GLBMY can inhibit the growth of TNBC through apoptosis and necroptosis pathways and inhibit TNBC lung metastasis by inhibiting epithelialmesenchymal transition(EMT).Network pharmacology has elucidated the most important active ingredients(tubeimoside I,emodin,cucurbitacin,and ursolic acid)and the most critical targets[interleukin-6(IL6),signal transducer and activator of transcription 3(STAT3),mitogen-activated protein kinase 3(MAPK3)]of GLBMY in treating TNBC.RNA-seq revealed that GLBMY affected the nuclear factor kappa-light-chain-enhancer of activated B cells,rat sarcoma virus,and MAPK signalling pathways.Metabolomics revealed that the metabolites mainly affected by GLBMY were L-(+)-lactic acid,isocitric acid,benzoic acid and indoxyl sulfate.Subsequent experiments demonstrated that GLBMY can inhibit EMT in TNBC through the MAPK/ERK pathway and inhibit the proliferation and progression of TNBC through the IL6-STAT signalling pathway.CONCLUSIONS:We confirmed that GLBMY inhibits the development and metastasis of TNBC through the MAPK/Erk and IL6-STAT signalling pathways.GLBMY shows promise as a long-term supplementary or alternative therapy for TNBC,offering new insights for TNBC treatment. 展开更多
关键词 triple negative breast neoplasms epithelialmesenchymal transition network pharmacology metabolomics Gualou Beimu Yin
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Numerical and Experimental Investigation of Filament-End Dynamics in Negative-Pressure Pneumatic Transport
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作者 Yisheng Liu Xufeng Sun Zhifeng Chen 《Fluid Dynamics & Materials Processing》 2026年第3期219-240,共22页
This study addresses the optimization of automated yarn handling in textile manufacturing by examining the related suction process through a combined numerical and experimental approach.In particular,a three-dimension... This study addresses the optimization of automated yarn handling in textile manufacturing by examining the related suction process through a combined numerical and experimental approach.In particular,a three-dimensional model of the suction nozzle was coupled with an equivalent linear-elastic beam representation of the yarn,and a Fluent-IDW-Abaqus weakly coupled fluid-structure interaction(FSI)framework was employed to capture the yarn’s release and dynamic response under negative-pressure suction.High-speed imaging experiments validated the simulations,demonstrating excellent agreement in displacements and velocities.According to the results,increasing the initial suction pressure from -0.04 MPa to -0.06 MPa reduces adsorption time by approximately 62% and markedly dampens yarn-end vibrations,enhancing suction performance.Pressures beyond -0.06 MPa,however,induce overshoot and nozzle collisions,increasing the risk of entanglement and mechanical damage.The outcomes of a statistical analysis are also presented to further quantify the interplay among energy consumption,suction efficiency,and operational success under varying pressures,thereby providing a rigorous foundation for the optimal selection of pressure parameters in automated yarn-handling systems. 展开更多
关键词 Yarn-end capture negative-pressure adsorption fluid-structure interaction(FSI) aerodynamic characteristics negative pressure jet
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Carbon-Neutral Pathways:Evaluating Renewable Technologies and Negative Emission Solutions
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作者 Ming Zhong Jingjing Yu Qingyu Hong 《Journal of Environmental & Earth Sciences》 2026年第2期183-201,共19页
The global transition to carbon neutrality is an urgent and multifaceted challenge that requires the deployment of renewable energy technologies and negative emission solutions(NETs)to reduce greenhouse gas emissions ... The global transition to carbon neutrality is an urgent and multifaceted challenge that requires the deployment of renewable energy technologies and negative emission solutions(NETs)to reduce greenhouse gas emissions across all sectors.This is a review article that looks at the contemporary environment of renewable technologies,such as solar,wind,biomass,hydropower,and geothermal,and how they might help to decarbonize the power sector and their combination with NETs.The paper also looks at the prospects of carbon capture,utilization,and storage,afforestation and reforestation,soil carbon sequestration,ocean-based,and enhanced weathering as some of the methods of offsetting the residual emissions.The article also outlines the economic,policy,and social factors required to have these solutions scaled up,such as the need to have good policy frameworks,invest in innovation,and the need to have the people on board.Lastly,it also gives the future perspective of having a carbon-neutral global economy,and it highlights that technology must be enhanced,more cooperation between countries must be established,and a holistic,open-ended way of attaining carbon neutrality. 展开更多
关键词 Carbon Neutrality Renewable Energy negative Emissions Technologies Carbon Capture and Storage Climate Policy
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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:4
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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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