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Applied Mathematics and Mechanics(English Edition) 2019年第5期40卷 649-678页

作者： Houjun KANG Tieding guo Weidong ZHU Junyi su Bingyu ZHAO Hunan Provincial Key Lab on Damage Diagnosis for Engineering Structures Hunan University Department of Mechanical Engineering University of Maryland College of Civil Engineering Hunan University

A dynamic model for an inclined carbon ?ber reinforced polymer(CFRP)cable is established, and the linear and nonlinear dynamic behaviors are investigated in detail. The partial differential equations for both the in-plane and out-of-plane dynamics of the inclined CFRP cable are obtained by Hamilton's principle. The linear eigenvalues are explored theoretically. Then, the ordinary differential equations for analyzing the dynamic behaviors are obtained by the Galerkin integral and dimensionless *** steady-state solutions of the nonlinear equations are obtained by the multiple scale method(MSM) and the Newton-Raphson method. The frequency-and force-response curves are used to investigate the dynamic behaviors of the inclined CFRP cable under simultaneous internal(between the lowest in-plane and out-of-plane modes) and external resonances, i.e., the primary resonances induced by the excitations of the in-plane mode,the out-of-plane mode, and both the in-plane mode and the out-of-plane mode, respectively. The effects of the key parameters, e.g., Young's modulus, the excitation amplitude,and the frequency on the dynamic behaviors, are discussed in detail. Some interesting phenomena and results are observed and concluded.

关键词： inclined carbon fiber reinforced polymer(CFRP)cable bifurcation nonlinear dynamics internal resonance external resonance

Analysis of risk factors for postpartum depression after cesarean section in women with early-onset preeclampsia

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World Journal of Psychiatry 2024年第10期14卷 1448-1457页

作者： Ran Wang Xin Liang xing-Yan su Department of Obstetrics and Gynecology The First People's Hospital of NanyangNanyang 473000Henan ProvinceChina Department of Nursing The First People's Hospital of NanyangNanyang 473000Henan ProvinceChina Department of Anesthesiology The Central Hospital of Enshi Tujia and Miao Autonomous PrefectureEnshi 445000Hubei ProvinceChina

BACKGROUND Early-onset preeclampsia significantly increases maternal and fetal morbidity and *** pregnant women with early onset preeclampsia choose cesarean section as their delivery *** extensive research has explored the association between postpartum depression(PPD)and cesarean section,few studies have investigated the risk factors after cesarean section in women with early-onset *** To examine these risk factors through a retrospective,observational analysis of 287 women who underwent a cesarean section for early preeclampsia between June 2014 and March *** Participants were assessed in person during the 32nd week of pregnancy,2 days post-cesarean,and 6 weeks *** to the Edinburgh Postnatal Depression Scale(EPDS),participants who underwent cesarean section were divided into PPD(n=60)and non-PPD groups(n=227).Furthermore,PPD was diagnosed at 6 weeks postpartum according to depressive symptoms(EPDS score≥11).The demographic and clinical features of PPD were *** logistic regression analysis was used to identify PPD risk *** The prevalence of PPD was 20.9%(60/287)among the 287 women who underwent cesarean section for early-onset *** logistic regression analyses revealed that advanced age(age>40 years)[odds ratio(OR)=1.93,95%CI:1.31-2.82],previous preeclampsia(OR=7.15,95%CI:5.81-8.85),pre-pregnancy obesity(OR=2.42,95%CI:1.62-3.63),gestational diabetes mellitus(OR=3.52,95%CI:2.51-4.92),preexisting hypertension(OR=1.35,95%CI:1.03-1.89),PPD symptoms(EPDS≥11)at 2 days postpartum(OR=6.15,95%CI:1.32-28.35),high prenatal self-rating anxiety scale score(OR=1.13,95%CI:1.06-1.18),and pain at 6 weeks postpartum(OR=2.16,95%CI:1.28-3.66)were independently associated with *** Risk factors for PPD after cesarean section in women with early-onset preeclampsia include advanced age(age>40 years),pre-pregnancy obesity,previous preeclampsia,gestational diabetes me

关键词： Postpartum depression Cesarean section Early-onset preeclampsia Depression Depressive symptoms Risk factor

ANALYSIS OF OVERFLOW CRITICAL VALUE FOR TiAl BASED ALLOY MELT DURING PROCESS OF CENTRIFUGAL CASTING

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中国有色金属学会会刊：英文版 1999年第2期9卷 3-8页

作者： guo, Jingjie Sheng, Wenbin su, Yanqing Ding, Hongsheng Jia, Jun Harbin Inst of Technology Harbin China

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关键词： angular velocityTiAl base alloypressure distributioncentrifugal casting

Fabrication of Microfluidic Fiber Chip Detection System

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稀有金属材料与工程 2006年第A03期35卷 525-526页

作者： Bo su Da-fu Cui Chang-chun Liu xing Chen State Key Lab. of Transducer Tech. Inst. of Electronics Chinese Academy of Sciences Beijing 100080 China

The diameter of the excitation beam was decreased greatly by integrating the fiber on the microfluidic chip as light propagation *** coupling efficiency of the fiber was improved with optical fiber collimation device coupling beam. The chip was placed in the darkroom to avoid the interference of the external *** cost of the instrument was decreased with a high brightness blue LED as excitation source;the performance of the system was valuated by the determination of FITC fluorescein with a minimum detectable concentration of 2.2×10^(-8) mol/L,the Signal-to-Noise Ratio (SNR) S/N=*** correlation coefficient of the detection system within the range of 1.8×10^(-7) mol/L～4×10^(-5)mol/L was 0.9972.

关键词： microfluidic chip light-emitting diode optical fiber detector

Single-nucleus RNA and ATAC sequencing analyses provide molecular insights into early pod development of peanut fruit

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Plant Communications 2024年第8期5卷 50-68页

作者： Yuanyuan Cui Yanning su Jianxin Bian Xue Han Haosong guo Zhiyuan Yang Yijun Chen Lihui Li Tianyu Li xing Wang Deng Xiaoqin Liu Peking University Institute of Advanced Agricultural Sciences Shandong Laboratory for Advanced Agricultural Sciences at WeifangShandong 261325China School of Advanced Agricultural Sciences Peking UniversityBeijing 100083China

Peanut(Arachis hypogaea L.)is an important leguminous oil and economic crop that produces flowers aboveground and fruits *** fruit-pod development,which significantly affects peanut production,involves complex molecular mechanisms that likely require the coordinated regulation of multiple genes in different *** investigate the molecular mechanisms that underlie peanut fruitpod development,we characterized the anatomical features of early fruit-pod development and integrated single-nucleus RNA-sequencing(snRNA-seq)and single-nucleus assay for transposase-accessible chromatin with sequencing(snATAC-seq)data at the single-cell *** identified distinct cell types,such as meristem,embryo,vascular tissue,cuticular layer,and stele cells within the shell *** specific cell types were used to examine potential molecular changes unique to each cell type during pivotal stages of fruit-pod ***-seq analyses of differentially expressed genes revealed cell-type-specific insights that were not previously obtainable from transcriptome analyses of bulk *** instance,we identified MADS-box genes that contributes to the formation of parenchyma cells and gravity-related genes that are present in the vascular cells,indicating an essential role for the vascular cells in peg ***,our single-nucleus analysis provides comprehensive and novel information on specific cell types,gene expression,and chromatin accessibility during the early stages of fruit-pod *** information will enhance our understanding of the mechanisms that underlie fruit-pod development in peanut and contribute to efforts aimed at improving peanut production.

关键词： peanut pod development single-nucleus RNA-seq single-nucleus ATAC-seq in situ RNA hybridization

Influences of phosphate nutritional level on the phytoavailability and speciation distribution of cadmium and lead in soil

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Journal of Environmental Sciences 2006年第6期18卷 1247-1253页

作者： CHEN su suN Tie-heng suN Li-na ZHOU Qi-xing CHAO Lei Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Key Laboratory of Environment Engineering of Shenyang University Shenyang 100041 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

A pot experiment was conducted to examine the influence of phosphate levels on the phytoavailability and speciation distribution of cadmium （Cd）, lead （Pb） in soil. Spring wheat （Triticum aestivum L.） was selected as the tested plant. There were 5 phosphate fertilizer（Ca（H2PO4）2） levels including 0, 50, 100, 200, and 400 mg P2O5/kg soil, marked by P0, P1, P2, P3, and P4, respectively. CdCl2·2.5H2o and Pb（NO3）2 were added to soil as the following levels： Cd ＋ Pb = 25＋0, 0＋1000, and 25＋1000 mg/kg, marked by T1, T2, and T3, respectively. The results showed that the P fertilizer promoted the dry weight of wheat in all treatments and alleviated the contamination induced by Cd and Pb. With increasing levels of the additional P fertilizer, Cd concentration in different parts （root, haulm, chaffand grain） of wheat decreased at the P1 level at first and then increased. The soluble plus exchangeable （SE） fraction of Cd in soil decreased at the P1 level and then increased from P2 to P4 levels. The moderate P fertilizer reduced the phytoavailability of Cd. The application of P could obviously restrain the uptake of Pb by wheat and there were significantly negative correlations between the levels of P and the uptake of Pb. Phosphorus supply resulted in a decrease in the SE fraction of Pb and there was a significantly negative correlation between the levels of P and the SE fraction of Pb in soil. All the levels of the P fertilizer in this experiment could reduce the phytoavailability of Pb. Thus, it is feasible to apply the P fertilizer （Ca（H2PO4）2） to Pb contaminated soils. However, the levels of P application should be restricted in case that redundant P may increase the phytoavailability of Cd.

关键词： phosphate phytoavailability speciation distribution cadmium lead

High Performance DNA Purification Microchip with Porous Silicon Dioxide Carrier Matrix

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稀有金属材料与工程 2006年第A03期35卷 284-287页

作者： xing Chen Dafu Cui Changchun Liu Bo su Haining Wang State Key Lab. of Transducer Tech. Inst. of Electronics Chinese Academy of Sciences Beijing 100080 China

Solid-phase extraction method has proven efficient and amenable to microchips.A novel DNA purification microchip was demonstrated using porous silicon dioxide as the solid phase *** SiO_2 was coated on the wall of the channel of the microchip to provide a surface-enlarging *** porous silicon was achieved by anodisation of the silicon reactor in a HF/ethanol mixture and then was oxidized thermally at a lower increasing/decreasing rate to form porous SiO_*** optimization of the preparing conditions a more stable microchip was *** with the microchip without the porous layer,the microchip with the porous SiO_2 layer achieved higher extracted efficiency of *** DNA from rat whole blood could be extracted and purified in 35 minutes.

关键词： microfluidic solid phase extraction porous SiO2 DNA purification

Artificial intelligence computed tomography helps evaluate the severity of COVID-19 patients:A retrospective study

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World Journal of Emergency Medicine 2022年第2期13卷 91-97页

作者： Yi Han su-cheng Mu Hai-dong Zhang Wei Wei xing-yue Wu Chao-yuan Jin guo-rong Gu Bao-jun Xie Chao-yang Tong Department of Emergency Medicine Zhongshan Hospital Fudan UniversityShanghai 200032China Department of Radiology Renmin Hospital of Wuhan UniversityWuhan 430060China

BACKGROUND:Computed tomography(CT)is a noninvasive imaging approach to assist the early diagnosis of ***,coronavirus disease 2019(COVID-19)shares similar imaging features with other types of pneumonia,which makes differential diagnosis *** intelligence(AI)has been proven successful in the medical imaging field,which has helped disease ***,whether AI can be used to identify the severity of COVID-19 is still ***:Data were extracted from 140 patients with confirmed *** severity of COVID-19 patients(severe ***-severe)was defined at admission,according to American Thoracic Society(ATS)guidelines for community-acquired pneumonia(CAP).The AI-CT rating system constructed by Hangzhou YITU Healthcare Technology Co.,*** used as the analysis tool to analyze chest CT ***:A total of 117 diagnosed cases were enrolled,with 40 severe cases and 77 non-severe *** patients had more dyspnea symptoms on admission(12 vs.3),higher acute physiology and chronic health evaluation(APACHE)II(9 vs.4)and sequential organ failure assessment(SOFA)(3 vs.1)scores,as well as higher CT semiquantitative rating scores(4 vs.1)and AI-CT rating scores than non-severe patients(P<0.001).The AI-CT score was more predictive of the severity of COVID-19(AUC=0.929),and ground-glass opacity(GGO)was more predictive of further intubation and mechanical ventilation(AUC=0.836).Furthermore,the CT semiquantitative score was linearly associated with the AI-CT rating system(Adj R2=75.5%,P<0.001).CONCLUSIONS:AI technology could be used to evaluate disease severity in COVID-19 *** it could not be considered an independent factor,there was no doubt that GGOs displayed more predictive value for further mechanical ventilation.

关键词： COVID-19 Artificial intelligence Chest computed tomography

Distribution of Deficit at Ruin for a PDMP Insurance Risk Model

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Acta Mathematicae Applicatae Sinica 2003年第3期19卷 521-528页

作者： guo-jingWang su-pingQian RongWu DepartmentofMathematics SuzhouUniversitySuzhou215006China DepartmentofMathematics ChangshuCollegeChangshu215500China DepartmentofMathematics NankaiUniversityTianjin300071China

In this paper we consider the risk process described by a piecewise deterministic Markov processes (PDMP). We mainly discuss the distribution of the deficit at ruin for the risk process. We derive the integrodi differential equation satisfied by this distribution. We obtain the explicit expressions for it for certain choices of the claim amount distribution.

关键词： Integro-differential equation risk process deficit at ruin survivor function

Fault Detection for a Class of Impulsive Switched Systems

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International Journal of Automation and computing 2014年第2期11卷 223-230页

作者： Qing-Yu su Yan-Cheng Li xing-Ze Dai Jian Li School of Automation Engineering Northeast Dianli University

The problem of fault detection for a class of nonlinear impulsive switched systems is investigated in this paper. Fault detection filters are designed such that the augmented systems are stable, and the residual error signal generated by the filters guarantees the H∞ performance for disturbances and faults. sufficient conditions for the design of fault detection(FD) filters are presented by linear matrix inequalities. Moreover, the filter gains are characterized according to a solution of a convex optimization. Finally, an example derived from a pulse-width-modulation-driven boost converter is given to illustrate the effectiveness of the FD design approach.

关键词： Impulsive switched systems fault detection(FD) H∞ performance dwell time filter design.