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MMP9、FeNO以及血清IgE与儿童哮喘急性发作严重程度的相关性分析 被引量:1
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作者 马秋实 李彤 王娜 《实用药物与临床》 CAS 2024年第3期183-187,共5页
目的研究呼出气一氧化氮(FeNO)、血清免疫球蛋白E(IgE)和基质金属蛋白酶9(MMP9)的水平与儿童哮喘急性发作之间的关系,为儿童哮喘的预防及治疗提供依据。方法选取沈阳市妇婴医院于2020年11月至2022年11月收治的98例支气管哮喘急性发作期... 目的研究呼出气一氧化氮(FeNO)、血清免疫球蛋白E(IgE)和基质金属蛋白酶9(MMP9)的水平与儿童哮喘急性发作之间的关系,为儿童哮喘的预防及治疗提供依据。方法选取沈阳市妇婴医院于2020年11月至2022年11月收治的98例支气管哮喘急性发作期儿童作为急性组,按照病情程度分成轻度组(n=32)、中度组(n=38)和重度组(n=28),按照2∶1的比例选出49例同期在门诊治疗的处于支气管哮喘缓解期的儿童作为缓解组,随机选取健康体检儿童49例作为健康对照组,分别对他们进行FeNO、MMP9和血清IgE及肺功能[用力肺活量(FVC)、1秒用力呼气量(FEV_(1))、FEV_(1)/FVC%、最大呼气流量(PEF)]检测。应用Pearson相关分析探讨哮喘急性发作期FeNO、MMP9及血清IgE和肺功能之间的联系,并对三者在支气管哮喘急性发作中的预测价值进行分析。结果急性组、缓解组和对照组的年龄、性别、体重指数和病程的比较,差异无统计学意义(P>0.05)。急性组FeNO、MMP9、血清IgE分别为(59.95±12.65)ppb、(4.87±1.44)pg/ml、(330.63±74.88)IU/ml,缓解组分别为(25.23±8.23)ppb、(1.21±0.02)pg/ml、(152.23±32.12)IU/ml,均高于对照组的(12.43±4.09)ppb、(0.53±0.24)pg/ml、(126.34±57.33)IU/ml,差异具有统计学意义(P<0.05)。急性期和缓解期FVC、FEV1、FEV1/FVC%、PEF均低于对照组,差异具有统计学意义(P<0.05)。支气管哮喘急性发作中度组FeNO、MMP9、血清IgE水平分别为(49.23±6.23)ppb、(1.21±0.02)pg/ml、(282.61±59.83)IU/ml,重度组分别为(67.43±10.09)ppb、(0.53±0.24)pg/ml、(356.49±70.82)IU/ml,均高于轻度组的(34.62±10.65)ppb、(4.87±1.44)pg/ml,(189.21±14.33)IU/ml,差异具有统计学意义(P<0.05)。在轻度组中FeNO、MMP9和血清IgE水平均较低,而在中度组中这些指标均较高,其中FVC、FEV_(1)、FEV_(1)/FVC%和PEF均较低,差异具有统计学意义(P<0.05)。FeNO以及MMP9与血清IgE水平呈正相关(P<0.05),FeNO、MMP9以及血清IgE水平与FVC、FEV_(1)、FEV_(1)/FVC%、PEF均呈负相关(P<0.05)。MMP9在支气管哮喘的诊断中表现出了显著的优势,当达到最大约登指数时,对应的截断值为1.17,曲线下面积(Area under curve,AUC)为0.83,敏感度和特异性也分别达到了90.13%和86.5%。结论支气管哮喘急性发作的儿童血清中的FeNO、MMP9以及血清IgE水平显著增高,随肺部功能恶化程度加重而上升,可能与支气管哮喘急性发作患儿肺功能损害程度有关。 展开更多
关键词 儿童支气管哮喘 血清IGE 基质金属蛋白酶9 呼出气一氧化氮 肺功能
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Probabilistic analysis of tunnel face seismic stability in layered rock masses using Polynomial Chaos Kriging metamodel 被引量:2
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作者 Jianhong Man Tingting Zhang +1 位作者 Hongwei Huang Daniel Dias 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2678-2693,共16页
Face stability is an essential issue in tunnel design and construction.Layered rock masses are typical and ubiquitous;uncertainties in rock properties always exist.In view of this,a comprehensive method,which combines... Face stability is an essential issue in tunnel design and construction.Layered rock masses are typical and ubiquitous;uncertainties in rock properties always exist.In view of this,a comprehensive method,which combines the Upper bound Limit analysis of Tunnel face stability,the Polynomial Chaos Kriging,the Monte-Carlo Simulation and Analysis of Covariance method(ULT-PCK-MA),is proposed to investigate the seismic stability of tunnel faces.A two-dimensional analytical model of ULT is developed to evaluate the virtual support force based on the upper bound limit analysis.An efficient probabilistic analysis method PCK-MA based on the adaptive Polynomial Chaos Kriging metamodel is then implemented to investigate the parameter uncertainty effects.Ten input parameters,including geological strength indices,uniaxial compressive strengths and constants for three rock formations,and the horizontal seismic coefficients,are treated as random variables.The effects of these parameter uncertainties on the failure probability and sensitivity indices are discussed.In addition,the effects of weak layer position,the middle layer thickness and quality,the tunnel diameter,the parameters correlation,and the seismic loadings are investigated,respectively.The results show that the layer distributions significantly influence the tunnel face probabilistic stability,particularly when the weak rock is present in the bottom layer.The efficiency of the proposed ULT-PCK-MA is validated,which is expected to facilitate the engineering design and construction. 展开更多
关键词 tunnel face stability Layered rock masses Polynomial Chaos Kriging(PCK) Sensitivity index Seismic loadings
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Knock-out of GhPDCT with the CRISPR/Cas9 system increases the oleic acid content in cottonseed oil 被引量:1
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作者 Tingwan Li Lu Long +5 位作者 Yingchao Tang Zhongping Xu Guanying Wang Man Jiang Shuangxia Jin Wei Gao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3468-3471,共4页
Cotton is a pivotal economic crop for natural textile fibers that also serves as an important source of edible oil(Long et al.2023).Cottonseed oil contains approximately14%oleic acid and 59%linoleic acid.An increase i... Cotton is a pivotal economic crop for natural textile fibers that also serves as an important source of edible oil(Long et al.2023).Cottonseed oil contains approximately14%oleic acid and 59%linoleic acid.An increase in monounsaturated fatty acids,particularly oleic acid,enhances the oxidative stability and nutritional value of edible oil(Chen et al.2021). 展开更多
关键词 CRISPR/Cas9 fibers SYSTEM
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基于CRISPR/Cas9技术建立Lepr与eNos双基因敲除的糖尿病肾病小鼠模型
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作者 赵苗妙 李明嘉 +3 位作者 李小亚 段蕊 张静宜 杨金奎 《首都医科大学学报》 CAS 北大核心 2024年第3期392-398,共7页
目的基于CRISPR/Cas9基因编辑技术建立瘦素受体基因(leptin receptor,Lepr)与血管内皮一氧化氮合酶基因(endothelial nitric oxide synthase,eNos)双基因敲除(double-knockout,DKO)小鼠模型,构建晚期糖尿病肾病小鼠模型。方法根据eNos... 目的基于CRISPR/Cas9基因编辑技术建立瘦素受体基因(leptin receptor,Lepr)与血管内皮一氧化氮合酶基因(endothelial nitric oxide synthase,eNos)双基因敲除(double-knockout,DKO)小鼠模型,构建晚期糖尿病肾病小鼠模型。方法根据eNos基因制备对应的gRNA,将CRISPR-Cas9体系显微注射于C57BL/Ks(BKS)背景小鼠的受精卵内。将受精卵转移至有假孕状态雌性小鼠的输卵管内部。幼鼠出生后经聚合酶链反应(polymerase chain reaction,PCR)鉴定及测序分析分选出为eNos^(+/-)基因型的F0代阳性小鼠,获得BKS背景下的Lepr基因杂合小鼠,即基因型为Lepr^(db/m)的Lepr-F0代杂合子小鼠。将eNos-F0与Lepr-F0代小鼠杂交,获得eNos^(+/-)/Lepr^(db/m)双杂合F1代小鼠,将双杂合F1代小鼠进一步交配,筛选得到Lepr与eNos双基因敲除小鼠。采用PCR法鉴定小鼠基因型,按基因鉴定结果分为野生型(wild-type,WT)组与DKO组小鼠。监测各组小鼠体质量、血糖与饮水进食量;采用酶联免疫吸附法(enzyme-linked immunosorbent assay,ELISA)检测小鼠尿白蛋白与尿肌酐水平,并计算尿白蛋白排泄率;苏木精-伊红(hematoxylin-eosin,HE)与过碘酸六胺银(periodic acid-silver metheramine,PASM)染色检查各组小鼠肾组织病理改变。结果PCR检测结果显示,成功构建lepr^(db/db)/eNos^(-/-)DKO小鼠。与同窝对照组相比,DKO小鼠的体质量、血糖水平与饮水进食量均显著高于同窝对照小鼠。DKO小鼠的尿白蛋白与尿白蛋白排泄率显著高于WT小鼠。病理学结果显示,DKO小鼠的肾小球体积明显增大,系膜基质增生明显。结论基于CRISPR/Cas9基因编辑技术可成功构建lepr^(db/db)/eNos^(-/-)DKO小鼠,DKO小鼠可反映糖尿病肾病的典型表现,为深入研究糖尿病肾病的作用机制提供动物模型。 展开更多
关键词 基因敲除 CRISPR/Cas9技术 糖尿病肾病 EnoS Lepr
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A review of the literature on the use of CRISPR/Cas9 gene therapy to treat hepatocellular carcinoma 被引量:1
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作者 ELHAM AMJAD RAFAELE PEZZANI BABAK SOKOUTI 《Oncology Research》 SCIE 2024年第3期439-461,共23页
Noncoding RNAs instruct the Cas9 nuclease to site speifillyl cleave DNA in the CRISPR/Cas9 system.Despite the high incidence of hepatocellular carcinoma(HCC),the patient's outcome is poor.As a result of the emerge... Noncoding RNAs instruct the Cas9 nuclease to site speifillyl cleave DNA in the CRISPR/Cas9 system.Despite the high incidence of hepatocellular carcinoma(HCC),the patient's outcome is poor.As a result of the emergence of therapeutic resistance in HCC patients,dlinicians have faced difficulties in treating such tumor.In addition,CRISPR/Cas9 screens were used to identify genes that improve the dlinical response of HCC patients.It is the objective of this article to summarize the current understanding of the use of the CRISPR/Cas9 system for the treatment of cancer,with a particular emphasis on HCC as part of the current state of knowledge.Thus,in order to locate recent developments in oncology research,we examined both the Scopus database and the PubMed database.The ability to selectively interfere with gene expression in combinatorial CRISPR/Cas9 screening can lead to the discovery of new effective HCC treatment regimens by combining clinically approved drugs.Drug resistance can be overcome with the help of the CRISPR/Cas9 system.HCC signature genes and resistance to treatment have been uncovered by genome-scale CRISPR activation screening although this method is not without limitations.It has been extensively examined whether CRISPR can be used as a tool for disease research and gene therapy.CRISPR and its applications to tumor research,particularly in HCC,are examined in this study through a review of the literature. 展开更多
关键词 CRISPR/Cas9 system Gene therapy TUMOR Hepatocellular carcinoma Liver cancer Gene editing
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Magnetic Switching Dynamics and Tunnel Magnetoresistance Effect Based on Spin-Splitting Noncollinear Antiferromagnet Mn_(3)Pt
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作者 朱蒙 董建艇 +4 位作者 李新录 郑凡星 周晔 吴琨 张佳 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第4期132-138,共7页
In comparison to ferromagnets,antiferromagnets are believed to have superior advantages for applications in next-generation magnetic storage devices,including fast spin dynamics,vanishing stray fields and robust again... In comparison to ferromagnets,antiferromagnets are believed to have superior advantages for applications in next-generation magnetic storage devices,including fast spin dynamics,vanishing stray fields and robust against external magnetic field,etc.However,unlike ferromagnetic orders,which could be detected through tunneling magnetoresistance effect in magnetic tunnel junctions,the antiferromagnetic order(i.e.,Néel vector)cannot be effectively detected by the similar mechanism due to the spin degeneracy of conventional antiferromagnets.Recently discovered spin-splitting noncollinear antiferromagnets,such as Mn_(3)Pt with momentum-dependent spin polarization due to their special magnetic space group,make it possible to achieve remarkable tunneling magnetoresistance effects in noncollinear antiferromagnetic tunnel junctions.Through first-principles calculations,we demonstrate that the tunneling magnetoresistance ratio can reach more than 800% in Mn_(3)Pt/perovskite oxides/Mn_(3)Pt antiferromagnetic tunnel junctions.We also reveal the switching dynamics of Mn_(3)Pt thin film under magnetic fields using atomistic spin dynamic simulation.Our study provides a reliable method for detecting Néel vector of noncollinear antiferromagnets through the tunnel magnetoresistance effect and may pave its way for potential applications in antiferromagnetic memory devices. 展开更多
关键词 tunnelING MAGNETORESISTANCE MOMENTUM
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Synthesis and Exciplex Emission of a Tricyano-substituted 9-Phenylfluorene Compound
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作者 Cao Hongtao Cao Qing +6 位作者 Hu Yangjun Yu Zimeng Xie Xinmiao Chang Yongzheng Hou Pengfei Wang Shasha Xie Linghai 《有机化学》 SCIE CAS CSCD 北大核心 2024年第8期2595-2602,共8页
Exciplex-emitters are attractive due to their distinct feature of easily achieving small singlet-triplet energy splitting for thermally activated delayed fluorescence(TADF),but face with challenges in convenient desig... Exciplex-emitters are attractive due to their distinct feature of easily achieving small singlet-triplet energy splitting for thermally activated delayed fluorescence(TADF),but face with challenges in convenient design of electron acceptors.New 9-phenylfluorene-based acceptor 9-[6-(2-cyano-7-isocyano-9-phenyl-9H-fluoren-9-yl)-9-ethyl-9H-carbazol-3-yl]-9-phenyl-9H-fluorene-2,7-dicarbonitrile(TriCNDPFCz)was designed and synthesized through tricyano-substitution.By mixing TriCNDPFCz with conventional donor 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane(TAPC),bright exciplex-TADF was obtained with a maximum current efficiency of 46.7 cd·A^(-1),power efficiency of 52.3 lm·W^(-1)and external quantum efficiency of 14.5%.The experimental characterizations indicate that tricyano-substitution in 9-phenylfluorene skeleton can form strong electron-accepting ability,which is useful and convenient for constructing electron acceptor in exciplex emission. 展开更多
关键词 9-phenylfluorene cyano-substitution asymmetric modification exciplex emission
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Evaluating the characteristics of geological structures in karst groundwater inflow, Nowsud Tunnel
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作者 BAYAT Narges SADEGHI Erfan NASSERY Hamid Reza 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3434-3452,共19页
Highly permeable geological structures such as dissolution channels, open fractures, and faults create environmental challenges regard to hydrological and hydrogeological aspects of underground construction, often cau... Highly permeable geological structures such as dissolution channels, open fractures, and faults create environmental challenges regard to hydrological and hydrogeological aspects of underground construction, often causing significant groundwater inflow during drilling due to the limitations of empirical and analytical methods. This study aims to identify the geological factors influencing water flow into the tunnel. High-flow zones' geological features have been identified and examined for this purpose. According to the geological complexity of the Nowsud tunnel, presence of different formations with different permeability and karstification have led to a high volume of underground inflow water (up to 4700 L/s) to the tunnel. The Nowsud tunnel faces significant geological and hydrogeological challenges due to its passage through the Ilam formation's LI2 unit, characterized by dissolution channels, faults, and fractures. The highest inflow rate (4700 L/s) occurred in the Hz-9 zone within the Zimkan anticline. The relationship between geological features and groundwater inflow indicates that anticlines are more susceptible to inflow than synclines. Additionally, different types of faults exhibit varying hydraulic effects, with strike-slip faults having the most significant impact on groundwater inflow, thrust faults conducting less water into the tunnel, and inflow through normal faults being negligible compared to the other two types of faults. The novelty of this paper lies in its detailed analysis of geological features influencing groundwater inflow into the Nowsud tunnel, providing empirical data on high-flow zones and differentiating the hydraulic effects of various fault types, which enhances the understanding and prediction of groundwater inflow in underground constructions. 展开更多
关键词 Geological structures Groundwater inflow HYDROGEOLOGY nowsud tunnel KARST
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Treatment of Synovial Cysts in Relation to the Tibial Tunnel of Anterior Cruciate Ligament Grafts by Filling the Tunnel with Acrylic Cement
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作者 Saint Luc Mungina Sedou Charlène Tshitala Mbombo +6 位作者 Yannick Toko Kiama Kevin Ndangi Ezechiel Nkodia Dieudonné Mwangala Rossyl Kivudi Dominique Saragaglia Luc Mokassa Bakumobatane 《Surgical Science》 2024年第4期289-298,共10页
Introduction: Synovial cyst of the tibial tunnel in connection with anterior cruciate ligament (ACL) reconstruction is a rare but particularly troublesome complication. Medical treatment is often doomed to failure, an... Introduction: Synovial cyst of the tibial tunnel in connection with anterior cruciate ligament (ACL) reconstruction is a rare but particularly troublesome complication. Medical treatment is often doomed to failure, and surgical treatment usually consists of excising the cyst and filling the tunnel with bone. The aim of this study was to evaluate the results of filling the tunnel with acrylic cement. Hypothesis: Filling the tibial bone tunnel with acrylic cement should eliminate communication between the joint cavity and the pre-tibial surface and prevent cyst recurrence. Patients and Methods: This retrospective series is composed of 13 patients, 9 men and 4 women, mean age 48.5 years (31 to 64) operated on between 2011 and 2019 for an intra- and extraosseous synovial cyst consecutive to the tibial tunnel of an ACL graft. Between 1983 and 2016, 12 of the patients had had a bone graft without bone block fixation (DI-DT or Mac Intosh) and one patient, a bone-bone transplant (KJ). The cyst was of variable size, located on the anteromedial aspect of the proximal end of the tibia, and often painful, warranting consultation. At the time of the initial operation, 9 patients had undergone meniscectomies (6 medial, 2 lateral, 1 double). In 7 knees, there were 7 cartilage lesions in the femorotibial and/or patellofemoral compartments (one stage 1 lesion, 2 stage 2 lesions, 4 stage 3 lesions, and no stage 4 lesions). Only 2 knees had neither cartilage nor meniscus lesions. After curettage of the bone tunnel /− removal of the non-resorbed or PEEK interference screw, the tunnel was filled with acrylic cement /− reinforced with a ligament staple to prevent expulsion. All patients underwent regular follow-up consultations until recovery. Results: At a maximum follow-up of 8 years, only 1 cyst recurred, representing a 7.69% failure rate. It was reoperated with another technique, which involved filling the tibial bone tunnel with bone graft taken from a half-bank head. After recovery, the cyst healed definitively. All patients were able to return to their previous activity within 15 days of surgery. Conclusion: Filling the tibial tunnel with acrylic cement reinforced /− with a ligament staple is a reliable and rapid solution for the treatment of intra- and extra-articular synovial cysts in relation to the tibial tunnel of ACL grafts. 展开更多
关键词 Arthro-Synovial Cyst Tibial tunnel ACL Graft FILLING Acrylic Cement
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Comparative Analysis of ARIMA and LSTM Model-Based Anomaly Detection for Unannotated Structural Health Monitoring Data in an Immersed Tunnel
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作者 Qing Ai Hao Tian +4 位作者 Hui Wang Qing Lang Xingchun Huang Xinghong Jiang Qiang Jing 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1797-1827,共31页
Structural Health Monitoring(SHM)systems have become a crucial tool for the operational management of long tunnels.For immersed tunnels exposed to both traffic loads and the effects of the marine environment,efficient... Structural Health Monitoring(SHM)systems have become a crucial tool for the operational management of long tunnels.For immersed tunnels exposed to both traffic loads and the effects of the marine environment,efficiently identifying abnormal conditions from the extensive unannotated SHM data presents a significant challenge.This study proposed amodel-based approach for anomaly detection and conducted validation and comparative analysis of two distinct temporal predictive models using SHM data from a real immersed tunnel.Firstly,a dynamic predictive model-based anomaly detectionmethod is proposed,which utilizes a rolling time window for modeling to achieve dynamic prediction.Leveraging the assumption of temporal data similarity,an interval prediction value deviation was employed to determine the abnormality of the data.Subsequently,dynamic predictive models were constructed based on the Autoregressive Integrated Moving Average(ARIMA)and Long Short-Term Memory(LSTM)models.The hyperparameters of these models were optimized and selected using monitoring data from the immersed tunnel,yielding viable static and dynamic predictive models.Finally,the models were applied within the same segment of SHM data,to validate the effectiveness of the anomaly detection approach based on dynamic predictive modeling.A detailed comparative analysis discusses the discrepancies in temporal anomaly detection between the ARIMA-and LSTM-based models.The results demonstrated that the dynamic predictive modelbased anomaly detection approach was effective for dealing with unannotated SHM data.In a comparison between ARIMA and LSTM,it was found that ARIMA demonstrated higher modeling efficiency,rendering it suitable for short-term predictions.In contrast,the LSTM model exhibited greater capacity to capture long-term performance trends and enhanced early warning capabilities,thereby resulting in superior overall performance. 展开更多
关键词 Anomaly detection dynamic predictive model structural health monitoring immersed tunnel LSTM ARIMA
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Investigation of FRP and SFRC Technologies for Efficient Tunnel Reinforcement Using the Cohesive Zone Model
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作者 Gang Niu Zhaoyang Jin +1 位作者 Wei Zhang Yiqun Huang 《Structural Durability & Health Monitoring》 EI 2024年第2期161-179,共19页
Amid urbanization and the continuous expansion of transportation networks,the necessity for tunnel construction and maintenance has become paramount.Addressing this need requires the investigation of efficient,economi... Amid urbanization and the continuous expansion of transportation networks,the necessity for tunnel construction and maintenance has become paramount.Addressing this need requires the investigation of efficient,economical,and robust tunnel reinforcement techniques.This paper explores fiber reinforced polymer(FRP)and steel fiber reinforced concrete(SFRC)technologies,which have emerged as viable solutions for enhancing tunnel structures.FRP is celebrated for its lightweight and high-strength attributes,effectively augmenting load-bearing capacity and seismic resistance,while SFRC’s notable crack resistance and longevity potentially enhance the performance of tunnel segments.Nonetheless,current research predominantly focuses on experimental analysis,lacking comprehensive theoretical models.To bridge this gap,the cohesive zone model(CZM),which utilizes cohesive elements to characterize the potential fracture surfaces of concrete/SFRC,the rebar-concrete interface,and the FRP-concrete interface,was employed.A modeling approach was subsequently proposed to construct a tunnel segment model reinforced with either SFRC or FRP.Moreover,the corresponding mixed-mode constitutive models,considering interfacial friction,were integrated into the proposed model.Experimental validation and numerical simulations corroborated the accuracy of the proposed model.Additionally,this study examined the reinforcement design of tunnel segments.Through a numerical evaluation,the effectiveness of innovative reinforcement schemes,such as substituting concrete with SFRC and externally bonding FRP sheets,was assessed utilizing a case study from the Fuzhou Metro Shield Tunnel Construction Project. 展开更多
关键词 tunnel segment FRP SFRC cohesive zone model constitutive model fracture process
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Three-dimensional pseudo-dynamic reliability analysis of seismic shield tunnel faces combined with sparse polynomial chaos expansion
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作者 GUO Feng-qi LI Shi-wei ZOU Jin-Feng 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2087-2101,共15页
To address the seismic face stability challenges encountered in urban and subsea tunnel construction,an efficient probabilistic analysis framework for shield tunnel faces under seismic conditions is proposed.Based on ... To address the seismic face stability challenges encountered in urban and subsea tunnel construction,an efficient probabilistic analysis framework for shield tunnel faces under seismic conditions is proposed.Based on the upper-bound theory of limit analysis,an improved three-dimensional discrete deterministic mechanism,accounting for the heterogeneous nature of soil media,is formulated to evaluate seismic face stability.The metamodel of failure probabilistic assessments for seismic tunnel faces is constructed by integrating the sparse polynomial chaos expansion method(SPCE)with the modified pseudo-dynamic approach(MPD).The improved deterministic model is validated by comparing with published literature and numerical simulations results,and the SPCE-MPD metamodel is examined with the traditional MCS method.Based on the SPCE-MPD metamodels,the seismic effects on face failure probability and reliability index are presented and the global sensitivity analysis(GSA)is involved to reflect the influence order of seismic action parameters.Finally,the proposed approach is tested to be effective by a engineering case of the Chengdu outer ring tunnel.The results show that higher uncertainty of seismic response on face stability should be noticed in areas with intense earthquakes and variation of seismic wave velocity has the most profound influence on tunnel face stability. 展开更多
关键词 reliability analysis shield tunnel face sparse polynomial chaos expansion modified pseudo-dynamic approach seismic stability assessment
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Support design method for deep soft-rock tunnels in non-hydrostatic high in-situ stress field
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作者 ZHENG Ke-yue SHI Cheng-hua +3 位作者 ZHAO Qian-jin LEI Ming-feng JIA Chao-jun PENG Zhu 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2431-2445,共15页
Due to the long-term plate tectonic movements in southwestern China,the in-situ stress field in deep formations is complex.When passing through deep soft-rock mass under non-hydrostatic high in-situ stress field,tunne... Due to the long-term plate tectonic movements in southwestern China,the in-situ stress field in deep formations is complex.When passing through deep soft-rock mass under non-hydrostatic high in-situ stress field,tunnels will suffer serious asymmetric deformation.There is no available support design method for tunnels under such a situation in existing studies to clarify the support time and support stiffness.This study first analyzed the mechanical behavior of tunnels in non-hydrostatic in-situ stress field and derived the theoretical equations of the ground squeezing curve(GSC)and ground loosening curve(GLC).Then,based on the convergence confinement theory,the support design method of deep soft-rock tunnels under non-hydrostatic high in-situ stress field was established considering both squeezing and loosening pressures.In addition,this method can provide the clear support time and support stiffness of the second layer of initial support.The proposed design method was applied to the Wanhe tunnel of the China-Laos railway in China.Monitoring data indicated that the optimal support scheme had a good effect on controlling the tunnel deformation in non-hydrostatic high in-situ stress field.Field applications showed that the secondary lining could be constructed properly. 展开更多
关键词 non-hydrostatic stress field high in-situ stress deep soft-rock tunnel squeezing pressure loosening pressure support design method
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Semi-analytical solution for mechanical analysis of tunnels crossing strike-slip fault zone considering nonuniform fault displacement and uncertain fault plane position
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作者 YANG Heng-hong WANG Ming-nian +1 位作者 YU Li ZHANG Xiao 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2116-2136,共21页
The tunnel subjected to strike-slip fault dislocation exhibits severe and catastrophic damage.The existing analysis models frequently assume uniform fault displacement and fixed fault plane position.In contrast,post-e... The tunnel subjected to strike-slip fault dislocation exhibits severe and catastrophic damage.The existing analysis models frequently assume uniform fault displacement and fixed fault plane position.In contrast,post-earthquake observations indicate that the displacement near the fault zone is typically nonuniform,and the fault plane position is uncertain.In this study,we first established a series of improved governing equations to analyze the mechanical response of tunnels under strike-slip fault dislocation.The proposed methodology incorporated key factors such as nonuniform fault displacement and uncertain fault plane position into the governing equations,thereby significantly enhancing the applicability range and accuracy of the model.In contrast to previous analytical models,the maximum computational error has decreased from 57.1%to 1.1%.Subsequently,we conducted a rigorous validation of the proposed methodology by undertaking a comparative analysis with a 3D finite element numerical model,and the results from both approaches exhibited a high degree of qualitative and quantitative agreement with a maximum error of 9.9%.Finally,the proposed methodology was utilized to perform a parametric analysis to explore the effects of various parameters,such as fault displacement,fault zone width,fault zone strength,the ratio of maximum fault displacement of the hanging wall to the footwall,and fault plane position,on the response of tunnels subjected to strike-slip fault dislocation.The findings indicate a progressive increase in the peak internal forces of the tunnel with the rise in fault displacement and fault zone strength.Conversely,an augmentation in fault zone width is found to contribute to a decrease in the peak internal forces.For example,for a fault zone width of 10 m,the peak values of bending moment,shear force,and axial force are approximately 46.9%,102.4%,and 28.7% higher,respectively,compared to those observed for a fault zone width of 50 m.Furthermore,the position of the peak internal forces is influenced by variations in the ratio of maximum fault displacement of the hanging wall to footwall and the fault plane location,while the peak values of shear force and axial force always align with the fault plane.The maximum peak internal forces are observed when the footwall exclusively bears the entirety of the fault displacement,corresponding to a ratio of 0:1.The peak values of bending moment,shear force,and axial force for the ratio of 0:1 amount to approximately 123.8%,148.6%,and 111.1% of those for the ratio of 0.5:0.5,respectively. 展开更多
关键词 strike-slip fault tunnel engineering semi-analytical solution fault zone width nonuniform fault displacement uncertain fault plane position
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Generation of double knockout cattle via CRISPR-Cas9 ribonucleoprotein(RNP)electroporation
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作者 Gyeong-Min Gim Kyeong-Hyeon Eom +10 位作者 Dong-Hyeok Kwon Dae-Jin Jung Dae-Hyun Kim Jun-Koo Yi Jae-Jung Ha Ji-Hyun Lee Seong-Beom Lee Woo-Jae Son Soo-Young Yum Won-Wu Lee Goo Jang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期456-462,共7页
Background Genome editing has been considered as powerful tool in agricultural fields.However,genome editing progress in cattle has not been fast as in other mammal species,for some disadvantages including long gestat... Background Genome editing has been considered as powerful tool in agricultural fields.However,genome editing progress in cattle has not been fast as in other mammal species,for some disadvantages including long gestational periods,single pregnancy,and high raising cost.Furthermore,technically demanding methods such as microinjection and somatic cell nuclear transfer(SCNT)are needed for gene editing in cattle.In this point of view,electroporation in embryos has been risen as an alternative.Results First,editing efficiency of our electroporation methods were tested for embryos.Presence of mutation on embryo was confirmed by T7E1 assay.With first combination,mutation rates for MSTN and PRNP were 57.6%±13.7%and 54.6%±13.5%,respectively.In case of MSTN/BLG,mutation rates were 83.9%±23.6%for MSTN,84.5%±18.0%for BLG.Afterwards,the double-KO embryos were transferred to surrogates and mutation rate was identified in resultant calves by targeted deep sequencing.Thirteen recipients were transferred for MSTN/PRNP,4 calves were delivered,and one calf underwent an induction for double KO.Ten surrogates were given double-KO embryos for MSTN/BLG,and four of the six calves that were born had mutations in both genes.Conclusions These data demonstrated that production of genome edited cattle via electroporation of RNP could be effectively applied.Finally,MSTN and PRNP from beef cattle and MSTN and BLG from dairy cattle have been born and they will be valuable resources for future precision breeding. 展开更多
关键词 BETA-LACTOGLOBULIN CATTLE CRISPR-Cas9 ELECTROPORATION KnoCKOUT MSTN PRNP
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On the Impairment of Stress-Induced Changes in Triglyceride Levels via a Sub-Toxic Dose of Unmethylated Cytidine Phosphate Guanosine Oligodinucleotide (a Toll-Like Receptor 9 Ligand)
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作者 Reiko Seki Kazuhisa Nishizawa 《Journal of Biosciences and Medicines》 2024年第9期95-112,共18页
Changes in lipid metabolism have been implicated in protection against infectious diseases. In the first experiment of this study, we measured clinical lipid parameters in a murine model where the unmethylated cytidin... Changes in lipid metabolism have been implicated in protection against infectious diseases. In the first experiment of this study, we measured clinical lipid parameters in a murine model where the unmethylated cytidine phosphate guanosine (CpG) oligodinucleotide (ODN1826), a Toll-like receptor 9 (TLR9) agonist was administered in combination with D-galactosamine (GalN) that caused relatively liver-specific inflammation and toxicity. In the control mice group injected with phosphate-buffered saline (PBS) (acute psychological stress model associated with blood sampling), the serum triglyceride (TG) levels showed a rapid decrease followed by a rebound at 24 h as we have recently reported. However, such a TG rebound was impaired in the CpG/GalN- and solely CpG-treated groups of mice despite an absence of liver injury based on serum alanine aminotransferase levels in the latter group. Thus, the stress-associated serum TG rebound was abrogated by the injection of a sub-hepatotoxic CpG dose. In the second experiment, we simply measured the hepatic CD36 and SACRB1 (the gene for scavenger receptor B1 (SR-B1)) transcripts after the i.p. administration of PBS, CpG or CpG/GalN. There was a remarkable elevation of hepatic CD36 transcript expression in both the CpG- and CpG/GalN-treated mice at 8 h post-CpG injection whereas the increase in the PBS-treated mice was slower than the former two groups, suggesting that hepatic CD36 transcript expression is more pronounced in the combined stress models than under psychological stress alone. The individual mice data showed that the increase in CD36 expression was accompanied by a reduction in SCARB1 mRNA, showing reciprocal regulation between these two genes. Together with our previously reported findings, these data suggest that, in a murine model combining psychological stress with TLR-triggered hepatic inflammation, the psychological stress facilitates liver uptake of plasma TG (and its components fatty acids), but the subsequent re-esterification and/or release of TG-rich lipoproteins from the liver is impaired due to the concomitant TLR-signaling. We hypothesize that lipid metabolism during acute stress shifts toward an elevated hepatic uptake of lipids due to concomitant TLR signaling, facilitating the clearance of bacterial lipids by the liver. 展开更多
关键词 Toll-Like Receptor 9 Cytidine Phosphate Guanosine Oligodinucleotide Scavenger Receptor B1 TRIGLYCERIDE Hepatic Inflammation
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Inactivated H9N2 vaccines developed with early strains do not protect against recent H9N2 viruses:Call for a change in H9N2 control policy
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作者 Yanjing Liu Qingqing Yu +8 位作者 Xiangyu Zhou Wenxin Li Xinwen He Yan Wang Guohua Deng Jianzhong Shi Guobin Tian Xianying Zeng Hualan Chen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期2144-2148,共5页
H9N2 virus has been widely distributed in wild birds and poultry around the world since its first emergence in the United States of America in 1966(Gu et al.2017;Carnaccini and Perez 2020).The virus appeared in chicke... H9N2 virus has been widely distributed in wild birds and poultry around the world since its first emergence in the United States of America in 1966(Gu et al.2017;Carnaccini and Perez 2020).The virus appeared in chickens in China in the early 1990s,and over the last two decades has gradually become the dominant epidemic subtype(Sun and Liu 2015;Bi et al.2020).Although H9N2 virus infection alone cannot cause severe disease or death in poultry,H9N2 virus-infected birds experience a degree of egg production drop and can be easily infected by other pathogens,thus causing economic losses for poultry industry. 展开更多
关键词 H9N2 POULTRY policy
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Effect of the mixing of s-wave and chiral p-wave pairings on electrical shot noise properties of normal metal/superconductor tunnel junctions
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作者 胡雨辰 胡梁宾 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期538-545,共8页
We study theoretically the electrical shot noise properties of tunnel junctions between a normal metal and a superconductor with the mixture of singlet s-wave and chiral triplet p-wave pairing due to broken inversion ... We study theoretically the electrical shot noise properties of tunnel junctions between a normal metal and a superconductor with the mixture of singlet s-wave and chiral triplet p-wave pairing due to broken inversion symmetry. We investigate how the shot noise properties vary as the relative amplitude between the two parity components in the pairing potential is changed. It is demonstrated that some characteristics of the electrical shot noise properties of such tunnel junctions may depend sensitively on the relative amplitude between the two parity components in the pairing potential, and some significant changes may occur in the electrical shot noise properties when the relative amplitude between the two parity components is varied from the singlet s-wave pairing dominated regime to the chiral triplet p-wave pairing dominated regime. In the chiral triplet p-wave pairing dominated regime, the ratio of noise power to electric current is close to 2e both in the in-gap and in the out-gap region. In the singlet s-wave pairing dominated regime, the value of this ratio is close to 4e in the inner gap region but may reduce to about 2e in the outer gap region as the relative amplitude of the chiral triplet pairing component is increased. The variations of the differential shot noise with the bias voltage also exhibit some significantly different features in different regimes. Such different features can serve as useful diagnostic tools for the determination of the relative magnitude of the two parity components in the pairing potential. 展开更多
关键词 normal metal/superconductor tunnel junctions shot noise mixing of s-wave and chiral p-wave pairing spin–orbit coupling
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Tunneling Electrons Triggered Energy Transfer between Coherently Coupled Donor-Acceptor Molecules
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作者 Huifang Wang 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第4期497-504,I0093,I0094,共10页
Energy transfer is ubiquitous in natural and artificial lightharvesting systems,and coherent energy transfer,a highly efficient energy transfer process,has been accepted to play a vital role in such systems.However,th... Energy transfer is ubiquitous in natural and artificial lightharvesting systems,and coherent energy transfer,a highly efficient energy transfer process,has been accepted to play a vital role in such systems.However,the energy oscillation of coherent energy transfer is exceedingly difficult to capture because of its evanescence due to the interaction with a thermal environment.Here a microscopic quantum model is used to study the time evolution of electrons triggered energy transfer between coherently coupled donoracceptor molecules in scanning tunneling microscope(STM).A series of topics in the plasmonic nanocavity(PNC)coupled donor-acceptor molecules system are discussed,including resonant and nonresonant coherent energy transfer,dephasing assisted energy transfer,PNC coupling strength dependent energy transfer,Fano resonance of coherently coupled donor-acceptor molecules,and polariton-mediated energy transfer. 展开更多
关键词 Energy transfer Coherent energy transfer Scanning tunneling microcopy induced luminescence Plasmonic nanocavity Quantum master equation DEPHASING Fano resonance Polariton-mediated energy transfer
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A simple and efficient CRISPR/Cas9 system permits ultra-multiplex genome editing in plants
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作者 Suting Wu Htin Kyaw +11 位作者 Zhijun Tong Yirong Yang Zhiwei Wang Liying Zhang Lihua Deng Zhiguo Zhang Bingguang Xiao William Paul Quick Tiegang Lu Guoying Xiao Guannan Qin Xue'an Cui 《The Crop Journal》 SCIE CSCD 2024年第2期569-582,共14页
The development and maturation of the CRISPR/Cas genome editing system provides a valuable tool for plant functional genomics and genetic improvement.Currently available genome-editing tools have a limited number of t... The development and maturation of the CRISPR/Cas genome editing system provides a valuable tool for plant functional genomics and genetic improvement.Currently available genome-editing tools have a limited number of targets,restricting their application in genetic research.In this study,we developed a novel CRISPR/Cas9 plant ultra-multiplex genome editing system consisting of two template vectors,eight donor vectors,four destination vectors,and one primer-design software package.By combining the advantages of Golden Gate cloning to assemble multiple repetitive fragments and Gateway recombination to assemble large fragments and by changing the structure of the amplicons used to assemble sg RNA expression cassettes,the plant ultra-multiplex genome editing system can assemble a single binary vector targeting more than 40 genomic loci.A rice knockout vector containing 49 sg RNA expression cassettes was assembled and a high co-editing efficiency was observed.This plant ultra-multiplex genome editing system advances synthetic biology and plant genetic engineering. 展开更多
关键词 CRISPR/Cas9 Multiplex genome editing Assembly system PLANT
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