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Use of the Attain Select Ⅱ catheter delivery system to improve left ventricular lead implantation in cardiac resynchronization therapy

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Chinese Medical Journal 2011年第8期124卷 1209-1212页

作者： ZHOU Xian-hui TANG Bao-peng li Jin-xin zhang Yu zhang Jiang-hua li Yao-dong Heart Center First Affiliated Hospital Xinjiang MedicalUniversity Urumqi Xinjiang 830000 China

Background Despite technical advances in tools used to facilitate implantation of cardiac resynchronization therapy （CRT） devices, there are many hurdles related mainly to the variation in the anatomy of the coronary veins. One such difficulty is the presence of a very sharply-angulated or tortuous of the lateral or posterolateral cardiac *** Totally 44 patients, 28 males and 16 females, with congestive heart failure and intraventricular conduction delay were studied retrospectively. There were 23 patients who had left ventricular （LV） lead implantation using standard techniques and equipment. For the other 21 patients with LV lead implantation we used the Attain Select Ⅱ catheter delivery system. The patients were seen every 3-6 months for 12 months and the efficacy of the primary procedure, LV lead implantation time, procedure and fluoroscopy time and the complications associated with the two techniques were *** There were no significant differences in the age, gender, New York Heart Association （NYHA） functional class,ischemic etiology, QRS duration, left ventricular ejection fraction, left ventricular end-diastolic diameter, left ventricular end-systolic diameter and LV dyssynchrony between the two groups. The LV lead implantation time, procedure time and fluoroscopy time were significantly shorter in the group using the Attain Select Ⅱ catheter delivery system; LV lead implantation time from （51-7） minutes to （40±7） minutes （P ＜0.001）, procedure time from （143±17） minutes to （124±18）minutes （P=0.001）, and fluoroscopy time from （45±7） minutes to （35±6） minutes （P＜0.001）. A successful procedure of LV lead implantation was significantly improved from 17/23 （74%） patients using the standard techniques and equipment, to 20/21 （95.3%） patients using the Attain Select Ⅱ catheter delivery system （P=0.06）Conclusion It is feasible and safe to implant LV leads through the coronary sinus using the Attain Select Ⅱ catheter delivery system.

关键词： cardiac resynchronization therapy congestive heart failure the Attain Select Ⅱ catheter delivery system left ventricular lead implantation

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Experimental Investigation on Vertical Hydraulic Transport of Ores in Deepsea Mining

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China Ocean Engineering 2024年第1期38卷 42-53页

作者： liU Lei liU Jian-cheng li xin XU li-xin zhang Xiu-zhan State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Sanya Yazhou Bay Institution of Deep-sea Sci-Tech Shanghai Jiao Tong UniversitySanya 572000China China Merchants Marine And Offshore Research Institute Co. Ltd.Shenzhen 518067China China Merchants Deepsea Research Institute(Sanya)Co. Ltd.Sanya 572000China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Deepsea mining has been proposed since the 1960s to alleviate the lack of resources on *** hydraulic transport of collected ores from the seabed to the sea surface is considered the most promising method for industrial *** the present study,an indoor model test of the vertical hydraulic transport of particles was conducted.A noncontact optical method has been proposed to measure the local characteristics of the particles inside a vertical pipe,including the local concentration and particle *** hydraulic gradient of ore transport was evaluated with various particle size distributions,particle densities,feeding concentrations and mixture flow *** transport,the local concentration is larger than the feeding concentration,whereas the particle velocity is less than the mixture *** qualitative effects of the local concentration and local fluid velocity on the particle velocity and slip velocity were *** local fluid velocity contributes significantly to particle velocity and slip velocity,whereas the effect of the local concentration is marginal.A higher feeding concentration and mixture flow velocity result in an increased hydraulic *** effect of the particle size gradation is slight,whereas the particle density plays a crucial role in the transport.

关键词： deepsea mining vertical hydraulic transport experiment flow characteristics

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Effect of Interface Form on Creep Failure and life of Dissimilar Metal Welds Involving Nickel-Based Weld Metal and Ferritic Base Metal

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 265-285页

作者： Xiaogang li Junfeng Nie xin Wang Kejian li Haiquan zhang Institute of Nuclear and New Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing 100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China

For dissimilar metal welds(DMWs)involving nickel-based weld metal(WM)and ferritic heat resistant steel base metal(BM)in power plants,there must be an interface between WM and BM,and this interface suffers mechanical and microstructure mismatches and is often the rupture location of premature *** this study,a new form of WM/BM interface form,namely double Y-type interface was designed for the *** behaviors and life of DMWs containing double Y-type interface and conventional I-type interface were compared by finite element analysis and creep tests,and creep failure mechanisms were investigated by stress-strain analysis and microstructure *** applying double Y-type interface instead of conventional I-type interface,failure location of DMW could be shifted from the WM/ferritic heat-affected zone(HAZ)interface into the ferritic HAZ or even the ferritic BM,and the failure mode change improved the creep life of *** interface premature failure of I-type interface DMW was related to the coupling effect of microstructure degradation,stress and strain concentrations,and oxide notch on the WM/HAZ *** creep failure of double Y-type interface DMW was the result of Type IV fracture due to the creep voids and micro-cracks on fine-grain boundaries in HAZ,which was a result of the matrix softening of HAZ and lack of precipitate pinning at fine-grain *** double Y-type interface form separated the stress and strain concentrations in DMW from the WM/HAZ interface,preventing the trigger effect of oxide notch on interface failure and inhibiting the interfacial microstructure *** is a novel scheme to prolong creep life and enhance reliability of DMW,by means of optimizing the interface form,decoupling the damage factors from WM/HAZ interface,and then changing the failure mechanism and shifting the failure location.

关键词： Dissimilar metal weld Nickel-based weld metal Ferritic heat resistant steel Interface Creep strain Microstructure Failure mechanism Creep life

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Joint fuzzy background and adaptive foreground model for moving target detection

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Frontiers of Computer Science 2024年第2期18卷 93-106页

作者： Dawei zhang Peng WANG Yongfeng DONG linhao li xin li School of Artificial Intelligence Hebei University of TechnologyTianjin 300401China Lane Department of Computer Science and Electrical Engineering West Virginia UniversityMorgantownWV 26506-6109USA

Moving target detection is one of the most basic tasks in computer *** conventional wisdom,the problem is solved by iterative optimization under either Matrix Decomposition(MD)or Matrix Factorization(MF)*** utilizes foreground information to facilitate background *** uses noise-based weights to fine-tune the *** both noise and foreground information contribute to the recovery of the *** jointly exploit their advantages,inspired by two framework complementary characteristics,we propose to simultaneously exploit the advantages of these two optimizing approaches in a unified framework called Joint Matrix Decomposition and Factorization(JMDF).To improve background extraction,a fuzzy factorization is *** fuzzy membership of the background/foreground association is calculated during the factorization process to distinguish their contributions of both to background *** describe the spatio-temporal continuity of foreground more accurately,we propose to incorporate the first order temporal difference into the group sparsity constraint *** temporal constraint is adjusted *** foreground and the background are jointly estimated through an effective alternate optimization process,and the noise can be modeled with the specific probability *** experimental results of vast real videos illustrate the effectiveness of our *** with the current state-of-the-art technology,our method can usually form the clearer background and extract the more accurate ***-noise experiments show the noise robustness of our method.

关键词： matrixdecomposition matrix factorization generalized sparsity noise modeling

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Huangqin flavonoid extraction for spinal cord injury in a rat model

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Neural Regeneration Research 2018年第12期13卷 2200-2208页

作者： Qian zhang li-xin zhang Jing An liang Yan Cui-Cui liu Jing-Jing Zhao Hao Yang Translational Medicine Center Hong Hui Hospital Xi'an Jiaotong University Department of Clinical Pharmacy Hong Hui Hospital Xi'an Jiaotong University Department of Spine Surgery Hong Hui Hospital Xi'an Jiaotong University

Flavonoids from Huangqin（dried roots of Scutellaria baicalensis Georgi） have anti-inflammatory effects, and are considered useful for treatment of spinal cord injury. To verify this hypothesis, the T9-10 spinal cord segments of rats were damaged using Allen＇s method to establish a rat spinal cord injury model. Before model establishment, Huangqin flavonoid extraction（12.5 g/kg） was administered intragastrically for 1 week until 28 days after model establishment. Methylprednisolone（30 mg/kg） was injected into the tail vein at 30 minutes after model establishment as a positive control. Basso, Beattie, and Bresnahan locomotor scale scores were used to assess hind limb motor function. Hematoxylin-eosin staining was used to detect pathological changes in the injured spinal cord. Immunofluorescence and western blot assays were performed to measure immunoreactivity and expression levels of brain-derived neurotrophic factor, neuronal marker neurofilament protein, microglial marker CD11 b and astrocyte marker glial fibrillary acidic protein in the injured spinal cord. Huangqin flavonoid extraction markedly reduced spinal cord hematoma, inflammatory cell infiltration and cavities and scars, and increased the Basso, Beattie, and Bresnahan locomotor scale scores; these effects were identical to those of methylprednisolone. Huangqin flavonoid extraction also increased immunoreactivity and expression levels of brain-derived neurotrophic factor and neurofilament protein, and reduced immunoreactivity and expression levels of CD11 b and glial fibrillary acidic protein, in the injured spinal cord. Overall, these data suggest that Huangqin flavonoid extraction can promote recovery of spinal cord injury by inducing brain-derived neurotrophic factor and neurofilament protein expression, reducing microglia activation and regulating reactive astrocytes.

关键词： nerve regeneration spinal cord injury flavonoids Scutellaria baicalensis neurofilament brain-derived neurotrophic factor astrocytes rnicroglia neural regeneration

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A Coupled Thermomechanical Crack Propagation Behavior of Brittle Materials by Peridynamic Differential Operator

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 339-361页

作者： Tianyi li xin Gu Qing zhang College of Architectural Engineering Jiangsu Open UniversityNanjing210036China Department of Engineering Mechanics Hohai UniversityNanjing211100China

This study proposes a comprehensive,coupled thermomechanical model that replaces local spatial derivatives in classical differential thermomechanical equations with nonlocal integral forms derived from the peridynamic differential operator(PDDO),eliminating the need for calibration *** model employs a multi-rate explicit time integration scheme to handle varying time scales in multi-physics *** simulations conducted on granite and ceramic materials,this model demonstrates its *** successfully simulates thermal damage behavior in granite arising from incompatible mineral expansion and accurately calculates thermal crack propagation in ceramic slabs during *** account for material heterogeneity,the model utilizes the Shuffle algorithm andWeibull distribution,yielding results that align with numerical simulations and experimental *** coupled thermomechanical model shows great promise for analyzing intricate thermomechanical phenomena in brittle materials.

关键词： Peridynamic differential operator thermomechanical coupling heterogeneity numerical simulation

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Efficacy and safety of sofosbuvir and daclatasvir in treatment of kidney transplantation recipients with hepatitis C virus infection

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World Journal of Gastroenterology 2017年第32期23卷 5969-5976页

作者： Yan Xue li-xin zhang Lei Wang Tao li Yun-Dong Qu Feng liu Department of Infectious Diseases and Hepatology the Second Hospital of Shandong University

AIM To assess the efficacy and safety of sofosbuvir and daclatasvir regimens for kidney transplantation(KT) patients with hepatitis C virus(HCV) *** This study enrolled a prospective cohort of consecutive Chinese KT patients with HCV infection. They were given sofosbuvir combined with daclatasvir, with or without ribavirin. They were monitored regularly during and after the treatment. RESULTS Six patients were recruited in our prospective study cohort. All patients were male and naive to directacting antiviral treatment. The treatment duration was 12 wk. Most patients(4/6) were infected with HCV genotype 1b. HCV RNA was undetectable at week 4 after treatment and at the end of treatment in all patients. Sustained virological response rate at 12 wk was 100%(6/6). Two patients had to accept a half dose of sofosbuvir due to serum creatinine elevation during treatment. Kidney function in the remaining patients was stable. No serious adverse events(AEs) were observed. No patient discontinued antiviral therapy due to side effects. CONCLUSION Sofosbuvir and daclatasvir for treatment of KT recipients with HCV infection are highly efficient and safe. Patients tolerated the medications well, and no serious AEs were observed. Larger prospective cohort studies are needed to validate these results.

关键词： Hepatitis C virus Sofosbuvir Daclatasvir Kidney transplantation Direct-acting antivirals

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Early Outcomes of Primary Total Hip Arthroplasty for Osteonecrosis of the Femoral Head in Patients with Human Immunodeficiency Virus in China

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Chinese Medical Journal 2015年第15期128卷 2059-2064页

作者： Chang-Song Zhao xin li Qiang zhang Sheng Sun Ru-Gang Zhao Juan Cai Department of Orthopedics Beijing Ditan Hospital Capital Medical University Beijing 100015 China

Background：Studies have reported that patients with human immunodeficiency virus （HIV） have a high incidence of osteonecrosis of the femoral head （ONFH）.Total hip arthroplasty （THA） is an effective management of ***,little data exist regarding the use of THA for the HIV patients with ONFH in *** study reviewed the outcomes of HIV-positive patients who underwent THA for ONFH,compared with HIV-negative ***：The patients who underwent THA for ONFH from September 2012 to September 2014 in Beijing Ditan Hospital,Capital Medical University were retrospectively ***-eight HIV-positive patients and 35 HIV-negative patients underwent 48 THAs and 45 THAs with cementless components,*** records and follow-up data were *** Hip Score （HHS） was applied to evaluate the pain and function of the hips before and after *** such as wound healing,surgical site infection,deep venous thrombosis,pulmonary embolism,sepsis,mortality,and complications from the prosthesis were *** operation time,blood loss,and hospital stay were compared between the two ***：The mean follow-up period was 19.5 ± 5.8 months （ranging from 6 to 30 months）.The mean age of the HIV-positive patients with osteonecrosis at the time of surgery was 35 years old,which was significantly lower than that of the HIV-negative group （42 years old）（P 〈 0.05）.The HIV-positive patients underwent surgery a mean of 2.5 years after their original symptoms,which was significantly shorter than the HIV-negatives＇（mean 4 years）（P 〈 0.05）.Among HIV-positive patients,the prevalence of being male and rate of bilateral procedures were significantly higher than those in the HIV-negative group （P 〈 0.05）.The operation time in HIV-positive patients was significantly longer than that in HIV-negative patients （P 〈 0.05）.There were no significant differences in blood loss or hospital stay between the two groups （P 〉 0.05）.The HHSs of two groups

关键词： Arthroplasty Harris Hip Score Hip Human Immunodeficiency Virus Infections Osteonecrosis of the Femoral Head Outcomes

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Hybrid model for BOF oxygen blowing time prediction based on oxygen balance mechanism and deep neural network

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 106-117页

作者： xin Shao Qing liu Zicheng xin Jiangshan zhang Tao Zhou Shaoshuai li State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Engineering Research Center of MES Technology for Iron&Steel Production Ministry of EducationBeijing 100083China Laiwu Iron and Steel Group Yinshan Section Steel Co. Ltd.Jinan 271104China

The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based on oxygen balance mechanism (OBM) and deep neural network (DNN) was established for predicting oxygen blowing time in converter. A three-step method was utilized in the hybrid model. First, the oxygen consumption volume was predicted by the OBM model and DNN model, respectively. Second, a more accurate oxygen consumption volume was obtained by integrating the OBM model and DNN model. Finally, the converter oxygen blowing time was calculated according to the oxygen consumption volume and the oxygen supply intensity of each heat. The proposed hybrid model was verified using the actual data collected from an integrated steel plant in China, and compared with multiple linear regression model, OBM model, and neural network model including extreme learning machine, back propagation neural network, and DNN. The test results indicate that the hybrid model with a network structure of 3 hidden layer layers, 32-16-8 neurons per hidden layer, and 0.1 learning rate has the best prediction accuracy and stronger generalization ability compared with other models. The predicted hit ratio of oxygen consumption volume within the error±300 m^(3)is 96.67%;determination coefficient (R^(2)) and root mean square error (RMSE) are0.6984 and 150.03 m^(3), respectively. The oxygen blow time prediction hit ratio within the error±0.6 min is 89.50%;R2and RMSE are0.9486 and 0.3592 min, respectively. As a result, the proposed model can effectively predict the oxygen consumption volume and oxygen blowing time in the converter.

关键词： basic oxygen furnace oxygen consumption oxygen blowing time oxygen balance mechanism deep neural network hybrid model

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Protective Effects of Phellodendron Species on Bone Health: A Novel Perspective on Their Potentials in Treating Osteoporosis and Osteoarthritis

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Chinese Journal of Integrative Medicine 2024年第4期30卷 379-384页

作者： xin li TAN Guo-yao zhang Qiang zhang Qun Good Clinical Practice Development Guangdong Provincial Key Laboratory of Bone and Joint Degeneration DiseasesThe Third Affiliated Hospital of Southern Medical UniversityGuangzhou(510630)China Department of Pharmacy Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou(510120)China

Phellodendron(PN)species,traditionally used in Chinese medicine for centuries,hold promise as a potential treatment for osteoporosis(OP)and osteoarthritis(OA)due to their bioactive *** bioactive compounds,including berberine and palmatine,exhibit anti-inflammatory,antioxidant,and bone-protective properties,contributing to their potential therapeutic benefits in promoting bone health and preventing bone ***,challenges such as the need for standardized preparation and dosing,limited clinical studies,and potential interactions with other medications hinder their clinical ***,the rich history of PN species in Chinese medicine provides a promising foundation for future investigation into their potential as alternative treatments for OP and *** research is needed to fully understand the underlying mechanisms of action and explore the clinical implications of PN for bone health.

关键词： Phellodendron species bone health osteoporosis osteoarthritis review

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