检索结果-南通市图书馆

Alterations in the gut microbiome after transjugular intrahepatic portosystemic shunt in patients with hepatitis B virus-related portal hypertension

引用

World Journal of Gastroenterology 2024年第31期30卷 3668-3679页

作者： Hong-wei Zhao Jin-Long Zhang Fu-Quan liu zhen-Dong Yue Lei Wang Yu Zhang Cheng-Bin Dong zhen-Chang Wang Department of Radiology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China Department of Radiology Beijing Tongren HospitalCapital Medical UniversityBeijing 100730China Department of Interventional Radiology Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China

BACKGROUND Gut microbiota(GM)affects the progression and response to treatment in liver *** GM composition is diverse and associated with different etiologies of liver ***,alterations in GM alterations are observed in patients with portal hypertension(PH)secondary to cirrhosis,with hepatitis B virus(HBV)infection being a major cause of cirrhosis in ***,understanding the role of GM alterations in patients with HBV infection-related PH is *** To evaluate GM alterations in patients with HBV-related PH after transjugular intrahepatic portosystemic shunt(TIPS)*** This was a prospective,observational clinical *** were 30 patients(with a 100%technical success rate)recruited in the present *** with esophagogastric variceal bleeding due to HBV infection-associated PH who underwent TIPS were *** samples were obtained before and one month after TIPS treatment,and GM was analyzed using 16S ribosomal RNA amplicon *** One month after TIPS placement,8 patients developed hepatic encephalopathy(HE)and were assigned to the HE group;the other 22 patients were assigned to the non-HE *** was no substantial disparity in the abundance of GM at the phylum level between the two groups,regardless of TIPS treatment(all,P>0.05).However,following TIPS placement,the following results were observed:(1)The abundance of Haemophilus and Eggerthella increased,whereas that of Anaerostipes,Dialister,Butyricicoccus,and Oscillospira declined in the HE group;(2)The richness of Eggerthella,Streptococcus,and Bilophila increased,whereas that of Roseburia and Ruminococcus decreased in the non-HE group;and(3)Members from the pathogenic genus Morganella appeared in the HE group but not in the non-HE *** Intestinal microbiota-related synergism may predict the risk of HE following TIPS placement in patients with HBVrelated *** microbiome therapies may be useful for preventing and trea

关键词： Transjugular intrahepatic portosystemic shunt Hepatic encephalopathy Gut microbiota Hepatitis B virus Portal hypertension

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Synthesis of core-shell nanostructured SiO_(2)/TiO_(2)photocatalysts via atomic layer deposition in a fluidized bed with central tube

引用

Particuology 2024年第8期91卷 19-28页

作者： wei liu Daoyin liu Zuyang Zhang zhenkun Sun Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy&EnvironmentSoutheast UniversityNanjing 210096China

Fluidized bed atomic layer deposition is an efficient technique for particle coating with precise control over the film thickness and uniformity at the *** this study,a fluidized bed with a central tube is designed,where the central tube has two roles:improve fluidization and deliver precursors *** synthesis of core-shell structured SiO_(2)/TiO_(2)nanoparticle catalysts for photodegradation of tetracycline hydrochloride(TC)is carried out using TiCl_(4)and H_(2)O as precursors at 180℃under atmospheric *** the combination of vibration and central tube,the segregation of agglomerate size along the bed height is weakened,and the prepared SiO_(2)/TiO_(2)nanoparticles show excellent photocatalytic degradation performance:the degradation efficiency on TC is 96%under 300 W xenon lamp irradiation for 60 *** mechanism of enhanced photocatalytic activity is due to the Ti-O-Si bonds generated at the interface,which increase the ability to absorb sunlight and accelerate the separation of holes and electrons.

关键词： SiO_(2)/TiO_(2)nanoparticles Fluidization Atomic layer deposition Photocatalysts Photocatalytic mechanism

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Global Stability to Steady Supersonic Rayleigh Flows in One-Dimensional Duct

引用

Chinese Annals of Mathematics,Series B 2024年第2期45卷 279-296页

作者： Fenglun wei Jianli liu Department of Mathematics Shanghai University Newtouch Center for Mathematics of Shanghai University

Heat exchange plays an important role in hydrodynamical systems,which is an interesting topic in theory and *** this paper,the authors consider the global stability of steady supersonic Rayleigh flows for the one-dimensional compressible Euler equations with heat exchange,under the small perturbations of initial and boundary conditions in a finite rectilinear duct.

关键词： Compressible Euler equations Heat exchange Supersonic Rayleigh fow Steady solution Classical solution

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

How to Construct a Lower Risk FOF Based on Correlation Network? The Method of Principal Component Risk Parity Asset Allocation

引用

Journal of Systems Science & Complexity 2024年第3期37卷 1052-1079页

作者： BAI wei ZHANG Junting liu Haifei liu Kai School of Management and Engineering Nanjing UniversityNanjing 210093China Postdoctoral Workstation of Bank of Jiangsu Co. LtdNanjing 210006China College of Finance Nanjing Agricultural UniversityNanjing 210095China University of Prince Edward Island 550 University AveCharlottetownPE C1A4P3Canada

In order to build a low-risk Fund of Funds(FOF), from the perspective of correlation, the principal component factor is used to improve the traditional risk parity model. Principal component analysis is used to decompose the underlying assets and generate unrelated principal component factors,and then the authors can construct a principal component risk parity portfolio. The proposed empirical results based on China’s mutual fund market show that the performance of principal component risk parity portfolio(PCRPP) is better than that of equal weight portfolio(EWP) and traditional risk parity portfolio(RPP). That is to say, not only the PCRPP in this paper has much lower risk than EWP and RPP, but also slightly better than EWP and RPP in terms of average return. Moreover, the study of dividing the underlying assets shows that the PCRPP in this paper is not sensitive to the underlying assets. The PCRPP in this paper is better than EWP and RPP for both the better performing funds and the worse performing funds. In addition, the empirical results on dynamic portfolio adjustments show that it is not appropriate to adjust asset allocation too frequently when the expected rate of return is calculated using the arithmetic mean.

关键词： Fund of funds(FOF) mutual funds portfolio risk principal component analysis risk parity portfolio

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Nest decoration:Black feathers prevent Crested Mynas from nest usurpation

引用

Avian Research 2024年第2期15卷 292-297页

作者： Jinmei liu wei Liang Ministry of Education Key Laboratory for Ecology of Tropical Islands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou571158China

Nests are important structures for birds to raise their offspring and for *** birds incorporate feathers into the nest,since feathers were traditionally thought to serve the function of *** in recent years have considered that some birds place feathers in conspicuous locations in the nest for decoration to trigger a fear response in the *** this study,we investigated whether decorative feathers could deter nest usurpation by Crested Mynas(Acridotheres cristatellus)by manipulating nest box *** results revealed that Crested Mynas preferred black feathers to white feathers as decorations and occupied nest boxes decorated with black feathers significantly less than those decorated with white feathers,suggesting that black decorative feathers in the nest could be more effective in preventing nest usurpation by Crested Mynas and that white decorative feathers may have other *** black feathers in the nest are prominently placed at the edge of the nest to convey the message that“this nest is occupied”or“the owner of this nest has been preyed upon”to visitor Crested Mynas,thus effectively preventing them from usurping the nest at a later stage.

关键词： Extended phenotype Feathers Nest decoration Nest usurpation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Performance analysis and multi-objective optimization based on a modified irreversible Stirling cycle

引用

Science China(Technological Sciences) 2024年第6期67卷 1668-1684页

作者： XU Lei YU MinJie liu ZhiChun liu wei School of Energy and Power Engineering Huazhong University of Science and TechnologyWuhan430074China

The efficiency of the actual Stirling engine is much lower than the ideal Carnot cycle *** obtain more precise efficiency for Stirling engines,this paper proposes a modified Stirling cycle with a more accurate heat transfer process in Stirling engines based on a thermodynamic function called available *** finite-time thermodynamic method is used to analyze the model performance under constant heat source temperature,finite temperature difference heat transfer,and incomplete regenerative processes.A new polytropic process is introduced to model the heat transfer between the working fluid and external heat sources in which only heat above ambient temperature is converted into technical *** regenerator is divided into numerous smaller heat reservoirs with individual temperature to analyze the incomplete regenerative *** expressions of the output power and thermal efficiency are obtained based on the modified irreversible Stirling cycle,and the effects of irreversible losses are analyzed to evaluate the performance of the proposed *** indicate that the efficiency of the modified cycle is much lower than that of the ideal Stirling cycle with an isothermal *** the increase of the average heat transfer temperature difference,there exists an optimum value for the power of the irreversible *** optimum power of the model was obtained for varying thermodynamic parameters by optimizing the average heat transfer temperature difference between the hot and cold *** optimize the irreversible model,the multi-objective optimization analysis is carried out based on NSGA-Ⅱ,which results in an optimized output power of 40.87 kW and an optimized thermal efficiency of 44%.

关键词： stirling cycle regenerative processes isopotential processes multi-objective optimization finite time thermodynamics

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Unified Classification and Rejection:A One-versus-all Framework

引用

Machine Intelligence Research 2024年第5期21卷 870-887页

作者： zhen Cheng Xu-Yao Zhang Cheng-Lin liu State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of SciencesBeijing100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing100049China

Classifying patterns of known classes and rejecting ambiguous and novel(also called as out-of-distribution(OOD))inputs are involved in open world pattern *** neural network models usually excel in closed-set classification while perform poorly in rejecting OOD *** tackle this problem,numerous methods have been designed to perform open set recognition(OSR)or OOD rejection/detection *** methods mostly take post-training score transformation or hybrid models to ensure low scores on OOD inputs while separating known *** this paper,we attempt to build a unified framework for building open set classifiers for both classification and OOD *** formulate the open set recognition of K-known-class as a(K+1)-class classification problem with model trained on known-class samples *** decomposing the K-class problem into K one-versus-all(OVA)binary classification tasks and binding some parameters,we show that combining the scores of OVA classifiers can give(K+1)-class posterior probabilities,which enables classification and OOD rejection in a unified *** maintain the closed-set classification accuracy of the OVA trained classifier,we propose a hybrid training strategy combining OVA loss and multi-class cross-entropy *** implement the OVA framework and hybrid training strategy on the recently proposed convolutional prototype network and prototype classifier on vision transformer(ViT)*** on popular OSR and OOD detection datasets demonstrate that the proposed framework,using a single multi-class classifier,yields competitive performance in closed-set classification,OOD detection,and misclassification *** code is available at https://***/zhen-cheng121/CPN_OVA_unified.

关键词： Open set recognition out-of-distribution detection misclassification detection convolutional prototype network oneversus-all Dempster-Shafer theory of evidence

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Printed Biosensors for the Detection of Alzheimer’s Disease Based on Blood Biomarkers

引用

Journal of Analysis and Testing 2024年第2期8卷 133-142页

作者： Yu Zeng zhen Huang Yibiao liu Tailin Xu Longgang Central Hospital of Shenzhen Shenzhen518116China School of Biomedical Engineering Shenzhen UniversityShenzhen518060China

Alzheimer’s disease(AD)is a chronic neurodegenerative disorder,and early diagnosis plays a crucial role in its prevention and *** recent years,blood-based biomarkers for early AD diagnosis have gained attention due to their non-invasiveness and minimal adverse reactions,which make them an attractive *** the onset of the COVID-19 pandemic,visiting large medical examination centers for blood tests has become increasingly *** trend is shifting towards community or home-based sampling,which relies on the development and application of portable,miniaturized,and highly sensitive *** the various sensors used for detecting blood biomarkers in AD,printed sensors demonstrate great potential in AD blood biomarker detection due to their ease of miniaturization,scalability for mass production,and compatibility with various detection *** this review,we focus on discussing the application of printed sensors in the analysis of blood biomarkers for *** also explore the challenges faced by printed sensors in early diagnosis based on AD blood biomarkers and propose potential solutions to address these challenges.

关键词： Printed biosensors Alzheimer’s disease Blood biomarkers Printing technology

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Differential Evolution Hemivariational Inequalities with Anti-periodic Conditions

引用

Acta Mathematica Sinica,English Series 2024年第4期40卷 1143-1160页

作者： Jing ZHAO Chun Mei GAN zhen Hai liu School of Mathematics and Quantitative Economics Guangxi University of Finance and EconomicsNanning 530003P.R.China Guangxi Colleges and Universities Key Laboratory of Optimization Control and Engineering Calculation Guangxi Minzu UniversityNanning 530006P.R.China

The goal of this paper is to deal with a new dynamic system called a differential evolution hemivariational inequality(DEHVI)which couples an abstract parabolic evolution hemivariational inequality and a nonlinear differential equation in a Banach ***,by apply ing surjectivity result for pseudomonotone multivalued mappins and the properties of Clarke's subgradient,we show the nonempty of the solution set for the parabolic hemivariational ***,some topological properties of the solution set are established such as boundedness,closedness and ***,we explore the upper semicontinuity of the solution ***,we prove the solution set of the system(DEHVI)is nonempty and the set of all trajectories of(DEHVI)is weakly compact in C(I,X).

关键词： Differential parabolic hemivariational inequality Clarke subdifferential hyperbolicparabolic system parabolic-parabolic system existence result

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Capacitor Voltage Imbalance Mechanism and Balancing Control of MMC When Riding Through PTG Fault

引用

CSEE Journal of Power and Energy Systems 2024年第2期10卷 778-785页

作者： zhen He Maozeng Lu Lijun Hang Pingliang Zeng Yanhua liu Hangzhou Dianzi University Hangzhou 310018China Shandong University of Technology Zibo 255000China State Grid Hangzhou Power Supply Company State GridHangzhou 310000China

Modular multilevel converter (MMC) based fault ride through (FRT) control is a promising solution to deal with the pole-to-ground (PTG) fault in high voltage direct current (HVDC) system. However, when MMC switches to the FRT control, capacitor voltage imbalance between upper and lower arms will occur, resulting in the deterioration of FRT performance. This letter provides a comprehensive analysis for the imbalance issue from the perspective of fundamental frequency circulating current (FFCC). It is found the imbalance during FRT stage will not expand continuously, but converge to a certain value gradually. The specific imbalance degree is closely associated with the amplitude of FFCC. In order to solve the imbalance issue, an open-loop balancing control is proposed. By introducing a fundamental frequency feedforward item to the inherent circulating current control, the proposed method can not only balance the capacitor voltages, but also minimize the amplitude of FFCC, and consequently the power loss of MMC during FRT process can be reduced. Finally, simulation results of PSCAD/ EMTDC verify the validity of theoretical analysis.

关键词： Balancing control capacitor voltage imbalance FFCC FRT control HVDC system PTG fault

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：