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A comparison of MLT wind between meteor radar chain data and SDWACCM results

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Earth and Planetary Physics 2022年第5期6卷 451-464页

作者： BaoZhu Zhou XiangHui Xue Wen Yi HaiLun Ye jie zeng JinSong Chen JianFei Wu TingDi Chen XianKang Dou CAS Key Laboratory of Geospace Environment Department of Geophysics and Planetary SciencesUniversity of Science and Technology of ChinaHefei 230026China Mengcheng National Geophysical Observatory School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory for the Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology Hefei 230026China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China Electronic Information School Wuhan UniversityWuhan 430072China

A meteor radar chain located along the 120°E meridian in the Northern Hemisphere from low to middle latitudes provides longterm horizontal wind observations of the mesosphere and lower thermosphere(MLT)*** this study,we report a seasonal variation and its latitudinal feature in the horizontal mean wind in the MLT region observed by six meteor radar instruments located at Mohe(53.5°N,122.3°E),Beijing(40.3°N,116.2°E),Mengcheng(33.4°N,116.5°E),Wuhan(30.6°N,114.4°E),Kunming(25.6°N,108.3°E),and Fuke(19.5°N,109.1°E)*** addition,we compare the wind in the MLT region measured by the meteor radar stations with those simulated by the Whole Atmosphere Community Climate Model(WACCM).In general,the WACCM appears to capture well the seasonal and latitudinal variations in the zonal wind *** particular,the temporal evolution of the eastward zonal wind maximum shifts from July to May as the latitude ***,the simulated WACCM meridional wind exhibits differences from the meteor radar observations.

关键词： meteor radar chain MLT horizontal wind tide SD-WACCM

Simplified quantitative analysis method and its application in the insitu synthesized copper-based azide chips

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Defence Technology（防务技术） 2024年第2期32卷 309-316页

作者： jie Ren Yunfeng Li Mingyu Li Xingyu Wu Jiabao Wang Qingxuan zeng State Key Laboratory of Explosion and Technology Beijing Institute of TechnologyBeijing 100081China

Copper-based azide(Cu(N_(3))2 or CuN_(3),CA)chips synthesized by in-situ azide reaction and utilized in miniaturized explosive systems has become a hot research topic in recent ***,the advantages of in-situ synthesis method,including small size and low dosage,bring about difficulties in quantitative analysis and differences in ignition capabilities of CA *** aim of present work is to develop a simplified quantitative analysis method for accurate and safe analysis of components in CA chips to evaluate and investigate the corresponding ignition *** this work,Cu(N_(3))2 and CuN_(3)components in CA chips were separated through dissolution and distillation by utilizing the difference in solubility and corresponding content was obtained by measuring N_(3)-concentration through *** spectrophotometry method was optimized by studying influencing factors and the recovery rate of different separation methods was studied,ensuring the accuracy and reproducibility of test *** optimized method is linear in range from 1.0-25.0 mg/L,with a correlation coefficient R^(2)=0.9998,which meets the requirements of CA chips with a milligram-level content *** with the existing ICP method,component analysis results of CA chips obtained by spectrophotometry are closer to real component content in samples and have satisfactory ***,as its application in miniaturized explosive systems,the ignition ability of CA chips with different component contents for direct ink writing CL-20 and the corresponding mechanism was *** study provided a basis and idea for the design and performance evaluation of CA chips in miniaturized explosive systems.

关键词： Copper-based azide chips Spectrophotometry Separation method Quantitative analysis Ignition ability

Effect of the sloping seabed on 3D soil-spudcan interaction using a material point-finite element(MPM-FEM)model

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1436-1454页

作者： Zhengda Lei Guangtian zeng Huaihui Ren Bisheng Wu Yuxin jie State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijingChina Key Laboratory of the Hydrosphere Sciences of the Ministry of Water Resources BeijingChina Institute of Ocean Engineering Tsinghua UniversityBeijingChina Longyuan (Beijing) Wind Power Engineering Technology Co. Ltd.BeijingChina

The sloping seabed affects the bearing capacity and failure mechanism of soil,which may compromise the stability and safety of offshore structures such as jack-up *** paper employs a coupled model combining the material point method and finite element method(MPM-FEM)to analyze the impact of sloping seabeds on the three-dimensional soil-spudcan *** MPM-FEM model implements the B¯approach to solve the challenge of volumetric locking due to the incompressibility constraints imposed by yield *** is validated against the centrifuge *** effects of sloping seabeds on penetration resistance,soil flow pattern,lateral response,stress distribution,and failure mechanism are *** soil mainly undergoes overall failure when the ratio of penetration depth to spudcan diameter(i.e.D P/D)is between 0 and *** the slope angle increases,the soil on the side of lower slope is expelled further,resulting in an asymmetric stress distribution and a larger horizontal sliding force of *** D P/D increases to 0.75,the soil transitions to localized plastic flow failure,and the range of soil flow affected by the spudcan penetration *** results show that,when the slope angle increases,the lateral displacement and stress distribution on the lower slope of a sloping seabed is significantly larger than that of a horizontal seabed,impacting the spudcan and surrounding soil *** study suggests that the seabed slope significantly affects the range of soil flow and failure at shallow penetration,indicating that the slope angle should be taken into account in the design and installation of offshore jack-up rigs,particularly in areas with sloping seabeds.

关键词： Soil-spudcan interaction Centrifuge tests MPM-FEM model B—approach Sloping seabeds Offshore structures

A Prognostic Nomogram with High Accuracy Based on 2D-SWE in Patients with Acute-on-chronic Liver Failure

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Journal of Clinical and Translational Hepatology 2022年第5期10卷 803-813页

作者： Lili Wu jieyang Jin Taicheng Zhou Yuankai Wu Xinhua Li Xiangyong Li jie zeng Jinfen Wang jie Ren Yutian Chong Rongqin Zheng Department of Medical Ultrasonics Third Affiliated Hospital of Sun Yat-Sen UniversityGuangdong Key Laboratory of Liver Disease ResearchGuangzhouGuangdongChina Department of Gastroenterological Surgery and Hernia Center Sixth Affiliated Hospital of Sun Yat-Sen UniversityGuangdong Institute of GastroenterologyGuangdong Provincial Key Laboratory of Colorectal and Pelvic Floor DiseasesSupported by National Key Clinical DisciplineGuangzhouGuangdongChina Department of Infectious Diseases Third Affiliated Hospital of Sun Yat-Sen UniversityGuangzhouGuangdongChina

Background and Aims:Acute-on-chronic liver failure(ACLF)is associated with very high *** prediction of prognosis is critical in navigating optimal treatment decisions to improve patient *** study was aimed to develop a new nomogram integrating two-dimensional shear wave elastography(2D-SWE)values with other independent prognostic factors to improve the precision of predicting ACLF patient ***:A total of 449 consecutive patients with ACLF were recruited and randomly allocated to a training cohort(n=315)or a test cohort(n=134).2D-SWE values,conventional ultrasound features,laboratory tests,and other clinical characteristics were included in univariate and multivariate *** with prognostic value were then used to construct a novel prognostic *** operating curves(ROCs)were generated to evaluate and compare the performance of the novel and published models including the Model for EndStage Liver Disease(MELD),MELD combined with sodium(MELD-Na),and Jin’s *** model was validated in a prospective cohort(n=102).Results:A ACLF prognostic nomogram was developed with independent prognostic factors,including 2D-SWE,age,total bilirubin(TB),neutrophils(Neu),and the international normalized ratio(INR).The area under the ROC curve(AUC)was 0.849 for the new model in the training cohort and 0.861 in the prospective validation cohort,which were significantly greater than those for MELD(0.758),MELD-Na(0.750),and Jin’s model(0.777,all p<0.05).Calibration curve analysis revealed good agreement between the predicted and observed *** new nomogram had superior overall net benefit and clinical ***:We established and validated a 2D-SWE-based noninvasive nomogram to predict the prognosis of ACLF patients that was more accurate than other prognostic models.

关键词： Acute-on-chronic liver failure Two-dimensional shear wave elastography Hepatitis B virus Prognosis

Characteristics of piecewise linear symmetric tri-stable stochastic resonance system and its application under different noises

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Chinese Physics B 2022年第8期31卷 273-288页

作者：张刚曾玉洁蒋忠均 School of Communication and Information Engineering Chongqing University of Posts and Telecommunications(CQUPT)Chongqing 400065China Cyberspace Administration of Guizhou Province Guiyang 550000China

Weak signal detection has become an important means of mechanical fault detections. In order to solve the problem of poor signal detection performance in classical tristable stochastic resonance system(CTSR), a novel unsaturated piecewise linear symmetric tristable stochastic resonance system(PLSTSR) is proposed. Firstly, by making the analysis and comparison of the output and input relationship between CTSR and PLSTSR, it is verified that the PLSTSR has good unsaturation characteristics. Then, on the basis of adiabatic approximation theory, the Kramers escape rate, the mean first-passage time(MFPT), and output signal-to-noise ratio(SNR) of PLSTSR are deduced, and the influences of different system parameters on them are studied. Combined with the adaptive genetic algorithm to synergistically optimize the system parameters, the PLSTSR and CTSR are used for numerically simulating the verification and detection of low-frequency, high-frequency,and multi-frequency signals. And the results show that the SNR and output amplitude of the PLSTSR are greatly improved compared with those of the CTSR, and the detection effect is better. Finally, the PLSTSR and CTSR are applied to the bearing fault detection under Gaussian white noise and Levy noise. The experimental results also show that the PLSTSR can obtain larger output amplitude and SNR, and can detect fault signals more easily, which proves that the system has better performance than other systems in bearing fault detection, and has good theoretical significance and practical value.

关键词： bearing fault detection weak signal detection piecewise linear symmetric tri-stable system output signal-noise-ratio adaptive genetic algorithm

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体表定位线对鼻咽癌放射治疗的影响

中国医疗设备 2024年第6期39卷 49-54页

作者：牛颢清齐斌曾杰陈锦辉邹力雷耀良广州医科大学附属肿瘤医院放射治疗科广东广州510091

目的探讨体表定位线对鼻咽癌放射治疗的影响。方法选取两种不同固定方式的184例鼻咽癌放疗患者为研究对象,A组采用U型定位膜+聚氨酯头枕固定,B组采用S型定位膜+发泡胶定位垫固定;每周行一次锥形束CT扫描校正体位,记录摆位误差;根据患者... 详细信息

目的探讨体表定位线对鼻咽癌放射治疗的影响。方法选取两种不同固定方式的184例鼻咽癌放疗患者为研究对象,A组采用U型定位膜+聚氨酯头枕固定,B组采用S型定位膜+发泡胶定位垫固定;每周行一次锥形束CT扫描校正体位,记录摆位误差;根据患者体表定位线的有/无,分别记作A1/A0组和B1/B0组;各组间行两两配对t检验,并按不同年龄段进行对比。结果各组摆位误差从小到大依次为B1组、B0组、A1组、A0组。其中,A0组与B1组线性摆位误差分别为(0.24±0.08)、(0.33±0.15)、(0.33±0.07)cm和(0.13±0.06)、(0.16±0.07)、(0.15±0.08)cm;旋转摆位误差分别为(1.60±0.60)°、(1.30±0.60)°、(1.50±0.70)°和(0.90±0.40)°、(0.80±0.40)°、(0.80±0.30)°。整体摆位误差在B1组和A0组之间差异有统计学意义(P0.05)。结论体表定位线结合S型定位膜+发泡胶定位垫可提高鼻咽癌放疗靶区摆位精度,具有临床实际意义。

关键词：鼻咽癌体表定位线发泡胶体位固定摆位误差

CRP、LDH、ESR与MPP恢复期患儿发生气道高反应性的关系分析

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临床和实验医学杂志 2024年第2期23卷 204-207页

作者：曾晓洁刘乐赵利娟伏伶王君霞西部战区总医院儿科四川成都610000

目的探究C-反应蛋白(CRP)、乳酸脱氢酶(LDH)、红细胞沉降率(ESR)与肺炎支原体肺炎(MPP)恢复期患儿发生气道高反应性(AHR)的关系分析。方法回顾性选择2019年8月至2022年8月于西部战区总医院住院的MPP恢复期患儿102例,根据患儿是否发生AHR... 详细信息

目的探究C-反应蛋白(CRP)、乳酸脱氢酶(LDH)、红细胞沉降率(ESR)与肺炎支原体肺炎(MPP)恢复期患儿发生气道高反应性(AHR)的关系分析。方法回顾性选择2019年8月至2022年8月于西部战区总医院住院的MPP恢复期患儿102例,根据患儿是否发生AHR,分为AHR组(n=48)及非AHR组(n=54)。比较两组的CRP、LDH、ESR水平、肺功能指标[用力肺活量(FVC)、第1 s用力呼气容积(FEV1)、峰值呼气流速(PEF)与最大呼气中段流速(MEF25-75)]、气道反应性指标[基础呼吸传导率(Grs cont)、基础呼吸阻力(Rrs cont)、传导率下降斜率(SGrs)、特异性气道传导下降第35百分位(PD35)、最小诱发累积剂量(Dmin)],分析CRP、LDH、ESR水平与气道反应性指标的相关性,并采用受试者工作特征(ROC)曲线评估CRP、LDH、ESR对MPP恢复期患儿发生AHR的预测价值。结果AHR组的CRP、LDH、ESR水平分别为(47.34±7.65)mg/L、(315.26±68.32)U/L、(45.71±6.25)mm/h,均高于非AHR组[(26.21±6.28)mg/L、(284.53±61.09)U/L、(31.46±5.13)mm/h],差异均有统计学意义(P<0.05)。AHR组的FVC、FEV1、PEF、MEF25-75水平分别为(83.01±10.43)%、(74.35±9.27)%、(70.29±7.63)%、(75.54±9.25)%,均低于非AHR组[(87.82±12.06)%、(83.49±12.38)%、(78.11±9.54)%、(80.02±10.37)%],差异均有统计学意义(P<0.05)。AHR组的Grs cont、SGrs、PD35、Dmin水平分别为(0.13±0.03)L/(s·cmH_(2)O)、(0.03±0.01)L/(s·cmH_(2)O·min)、1.59±0.42、1.24±0.33,均低于非AHR组[(0.17±0.05)L/(s·cmH_(2)O)、(0.05±0.02)L/(s·cmH_(2)O·min)、4.06±1.15、3.97±0.82],Rrs cont水平为(8.75±1.63)cmH_(2)O/(L·s),高于非AHR组[(8.12±1.31)cmH_(2)O/(L·s)],差异均有统计学意义(P<0.05)。CRP、LDH、ESR与患儿的Grs cont、SGrs、PD35、Dmin水平均呈负相关(P<0.05),CRP、LDH、ESR与患儿Rrs cont水平均呈正相关(P<0.05)。ROC曲线分析结果显示,3项指标联合预测MPP儿童恢复期发生AHR的曲线下面积为0.878,均高于单一的CRP、LDH、ESR的0.804、0.674、0.760。结论CRP、LDH、ESR可作为MPP恢复期患儿发生AHR的重要标志物,可为临床评估患儿病情及用药提供参考。

关键词：肺炎支原体肺炎 C反应蛋白质乳酸脱氢酶类红细胞沉降率气道高反应性

Recent advances in engineering iron oxide nanoparticles for effective magnetic resonance imaging

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Bioactive Materials 2022年第6期7卷 214-245页

作者： Zhenghuan Zhao Muyao Li jie zeng Linlin Huo Kun Liu Ruixue Wei Kaiyuan Ni Jinhao Gao College of Basic Medical Sciences Chongqing Medical UniversityChongqing400016China State Key Laboratory of Physical Chemistry of Solid Surfaces The Key Laboratory for Chemical Biology of Fujian ProvinceAnd Department of Chemical Biology College of Chemistry and Chemical Engineering Xiamen UniversityXiamenFujian361005China Department of Cerebrovascular Diseases The Second Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan450052China Koch Institute for Integrative Cancer Research Massachusetts Institute of TechnologyCambridgeMA02142United States

Iron oxide nanoparticle(IONP)with unique magnetic property and high biocompatibility have been widely used as magnetic resonance imaging(MRI)contrast agent(CA)for long ***,a review which comprehensively summarizes the recent development of IONP as traditional T_(2) CA and its new application for different modality of MRI,such as T_(1) imaging,simultaneous T_(2)/T_(1) or MRI/other imaging modality,and as environment responsive CA is *** review starts with an investigation of direction on the development of high-performance MRI CA in both T_(2) and T_(1) modal based on quantum mechanical outer sphere and Solomon-Bloembergen-Morgan(SBM)*** rational attempts to increase the MRI contrast of IONP by adjusting the key parameters,including magnetization,size,effective radius,inhomogeneity of surrounding generated magnetic field,crystal phase,coordination number of water,electronic relaxation time,and surface modification are *** the strategies to improve r2 or r1 values,strategies to increase the in vivo contrast efficiency of IONP have been reviewed from three different aspects,those are introducing second imaging modality to increase the imaging accuracy,endowing IONP with environment response capacity to elevate the signal difference between lesion and normal tissue,and optimizing the interface structure to improve the accumulation amount of IONP in *** detailed review provides a deep understanding of recent researches on the development of high-performance IONP based MRI *** is hoped to trigger deep thinking for design of next generation MRI CAs for early and accurate diagnosis.

关键词： Iron oxide nanoparticles Improved relaxation Dual-modal contrast imaging Environment responsive imaging Strcture engineering

舒筋健脑方干预脑瘫模型大鼠减轻大脑皮质的组织炎症反应

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中国组织工程研究 2024年第23期28卷 3674-3679页

作者：刘港曾杰赵亚林邓博文蒋昇源张亚奇赵毅任敬佩胡传宇徐林穆晓红北京中医药大学东直门医院北京市100007 重庆市中医院重庆市400011 北京市丰台康复医院北京市100161

背景:舒筋健脑方是北京中医药大学东直门医院治疗脑瘫的经验方剂,临床疗效明确,但具体作用机制有待阐明。目的:探讨舒筋健脑方治疗脑性瘫痪的可能作用机制。方法:64只7 d龄SD大鼠幼鼠随机分为正常组12只和造模组52只。造模组幼鼠采用Ric... 详细信息

背景:舒筋健脑方是北京中医药大学东直门医院治疗脑瘫的经验方剂,临床疗效明确,但具体作用机制有待阐明。目的:探讨舒筋健脑方治疗脑性瘫痪的可能作用机制。方法:64只7 d龄SD大鼠幼鼠随机分为正常组12只和造模组52只。造模组幼鼠采用Rice-Vannucci法建立模型,造模成功的52只幼鼠随机分为模型组12只、米诺环素组及舒筋健脑方低、中、高剂量组各10只。米诺环素组大鼠给予40 mg/(kg•d)盐酸米诺环素灌胃;舒筋健脑方低、中、高剂量组分别给予舒筋健脑方颗粒4,8,16 g/(kg•d)灌胃;正常组及模型组给予等剂量生理盐水灌胃。各组每日灌胃1次,连续干预1周。各组大鼠采用悬吊实验、不自主动作评分、Bederson评分进行行为学评价;苏木精-伊红染色观察大脑皮质组织病理改变;Elisa法检测大脑皮质组织炎症相关因子水平;免疫组化检测大脑皮质组织酪氨酸激酶2(Janus kinase 2,JAK2)、磷酸化酪氨酸激酶2(Phosphorylated janus kinase 2,p-JAK2)及磷酸化信号转导子和转录激活子3(Phosphorylated signal transducer and activator of transcription 3,p-STAT3)阳性表达;Western blot检测JAK2、p-JAK2、p-STAT3蛋白表达水平。结果与结论:①与正常组比较,模型组大鼠悬吊实验得分、不自主动作得分降低(P<0.01或P<0.05);神经细胞结构破坏,大量空泡形成,细胞肿胀,细胞间隙增大;大脑皮质组织肿瘤坏死因子α、白细胞介素1β水平显著升高(P<0.01),白细胞介素10水平降低(P<0.05);大脑皮质组织JAK2、p-JAK2、p-STAT3蛋白表达显著升高(P<0.01)。②与模型组比较,米诺环素组及舒筋健脑方各剂量组大鼠行为学指标改善(P<0.01或P<0.05);缺血缺氧性病理改变减轻,仅有少量神经细胞坏死及少量空泡形成,细胞间隙减小;大脑皮质组织肿瘤坏死因子α、白细胞介素1β水平降低(P<0.05);大脑皮质组织JAK2、p-JAK2、p-STAT3蛋白表达显著降低(P<0.01);舒筋健脑方高剂量各指标改善最明显。③结果说明,舒筋健脑方能够抑制缺血缺氧脑损伤模型大鼠大脑皮质组织炎症反应,其作用机制可能与调节JAK2/STAT3信号通路有关。

关键词：脑性瘫痪舒筋健脑方炎症反应 JAK2/STAT3信号通路