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Effect of existence state of asphaltenes on the asphaltenes-wax interaction in wax deposition

Petroleum Science 2023年第1期20卷 507-514页

作者： Yun Lei Han Wang Shuang-Shuang Li xue-qian liu Hao-Ran Zhu Yu-Ming Gao Hao-Ping Peng Peng-Fei Yu Jiangsu Key Laboratory of Oil and Gas Storage&Transportation Technology Changzhou UniversityJiangsu213164China

Asphaltenes are the most elusive substances in waxy crude oil,especially the complex structures,which leads to significant precipitation and aggregation characteristics of asphaltenes,and affects the asphaltenes-wax interaction.In this study,the concept of the existence state of asphaltenes was introduced to semi-quantitatively investigate the precipitation and aggregation characteristics of asphaltenes.On this basis,the influence of the existence state of asphaltenes on wax deposition was studied by coldfinger device and high-temperature gas chromatography,and the composition and properties of the deposits were analyzed.Four main findings were made:(1)As the asphaltene concentration increases,the existence state of asphaltenes gradually transitions from dispersed state to aggregated state,and the asphaltene concentration of 0.30 wt%in this study is the starting point of the transition.(2)The existence state of asphaltenes in crude oil does affect the process of wax deposition,as shown in the fact that the dispersed asphaltenes promote the occurrence of wax deposition,while the aggregated asphaltenes can inhibit wax deposition.(3)In the presence of the aggregated asphaltenes,that is,when the asphaltene concentration is higher than 0.30 wt%,the shedding phenomenon of deposit layer was observed,and with the increase of aggregated asphaltenes,the deposit layer fell off earlier.(4)With the increase of the dispersed asphaltenes,the wax appearance temperature(WAT)and wax content of the deposits all showed an increasing trend,while with the appearance of the aggregated asphaltenes,the above situation was reversed.The findings of this study can help for better understanding of the interaction between the asphaltenes and wax in wax deposition.

关键词： Asphaltenes Precipitation/aggregation Existence state of asphaltenes Deposition

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Online calculator for predicting the risk of malignancy in patients with pancreatic cystic neoplasms: A multicenter, retrospective study

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World Journal of Gastroenterology 2022年第37期28卷 5469-5482页

作者： Dong Jiang Zi-Xiang Chen Fu-Xiao Ma Yu-Yong Gong Tian Pu Jiang-Ming Chen xue-qian liu Yi-Jun Zhao Kun Xie Hui Hou Cheng Wang Xiao-Ping Geng Fu-Bao liu Department of General Surgery The First Affiliated Hospital of Anhui Medical UniversityHefei 230000Anhui ProvinceChina Department of General Surgery The Second Affiliated Hospital of Anhui Medical UniversityHefei 230000Anhui ProvinceChina Department of General Surgery The First Affiliated Hospital of University of Science and Technology of ChinaHefei 230000Anhui ProvinceChina

BACKGROUND Efficient and practical methods for predicting the risk of malignancy in patients with pancreatic cystic neoplasms(PCNs)are lacking.AIM To establish a nomogram-based online calculator for predicting the risk of malignancy in patients with PCNs.METHODS In this study,the clinicopathological data of target patients in three medical centers were analyzed.The independent sample t-test,Mann–Whitney U test or chi-squared test were used as appropriate for statistical analysis.After univariable and multivariable logistic regression analysis,five independent factors were screened and incorporated to develop a calculator for predicting the risk of malignancy.Finally,the concordance index(C-index),calibration,area under the curve,decision curve analysis and clinical impact curves were used to evaluate the performance of the calculator.RESULTS Enhanced mural nodules[odds ratio(OR):4.314;95%confidence interval(CI):1.618–11.503,P=0.003],tumor diameter≥40 mm(OR:3.514;95%CI:1.138–10.849,P=0.029),main pancreatic duct dilatation(OR:3.267;95%CI:1.230–8.678,P=0.018),preoperative neutrophil-to-lymphocyte ratio≥2.288(OR:2.702;95%CI:1.008–7.244,P=0.048],and preoperative serum CA19-9 concentration≥34 U/mL(OR:3.267;95%CI:1.274–13.007,P=0.018)were independent risk factors for a high risk of malignancy in patients with PCNs.In the training cohort,the nomogram achieved a C-index of 0.824 for predicting the risk of malignancy.The predictive ability of the model was then validated in an external cohort(C-index:0.893).Compared with the risk factors identified in the relevant guidelines,the current model showed better predictive performance and clinical utility.CONCLUSION The calculator demonstrates optimal predictive performance for identifying the risk of malignancy,potentially yielding a personalized method for patient selection and decision-making in clinical practice.

关键词： Pancreatic cystic neoplasms Risk of malignancy Nomogram Model Prediction Calculator

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Comparison of Rotating Stall Warning by Different Methods for Variable Speed Configurations in a Contra-Rotating Compressor

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Journal of Thermal Science 2024年第4期33卷 1379-1393页

作者： xue Fei WANG Yan'gang liu qian WU Tong liu Hanru School of Power and Energy Northwestern Polytechnical University

Stall in compressors can cause performance degradation and even lead to disasters.These unacceptable consequences can be avoided by timely monitoring stall inception and taking effective measures.This paper focused on the rotating stall warning in a low-speed axial contra-rotating compressor.Firstly,the stall disturbance characteristics under different speed configurations were analyzed.The results showed that as the speed ratio(RR)increased,the stall disturbance propagation speed based on the rear rotor speed gradually decreased.Subsequently,the standard deviation(SD) method,the cross-correlation(CC) method,and the discrete wavelet transform(DWT)method were employed to obtain the stall initiation moments of three different speed configurations.It was found that the SD and CC methods did not achieve significant stall warning results in all three speed configurations.Besides,the stall initiation moment obtained by the DWT method at RR=1.125 was one period after the stall had fully developed,which was unacceptable.Therefore,a stall warning method was developed in the present work based on the long short-term memory(LSTM) regression model.By applying the LSTM model,the predicted stall initiation moments of three speed configurations were at the 557th,518th,and 333rd revolution,which were44,2,and 74 revolutions ahead of stall onset moments,respectively.Furthermore,in scenarios where a minor disturbance preceded the stall,the stall warning effect of the LSTM was greatly improved in comparison with the aforementioned three methods.In contrast,when the pressure fluctuation before the stall was relatively small,the differences between the stall initiation moments predicted by these four methods were not significant.

关键词： contra-rotating compressor stall disturbance stall initiation moment long short-term memory (LSTM) stall warning

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The joint knowledge reasoning model based on knowledge representation learning for aviation assembly domain

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Science China(Technological Sciences) 2024年第1期67卷 143-156页

作者： liu PeiFeng qian Lu LU Hu xue Lei ZHAO XingWei TAO Bo State Key Laboratory of Digital Manufacturing Equipment and Technology Department of MechanicalHuazhong University of Science and TechnologyWuhan 430074China School of Transportation and Logistics Engineering Wuhan University of Technology(WHUT)Wuhan 430063China Shanghai Aircraft Manufacturing Co. Ltd.Shanghai 201324China

Knowledge graph technology is widely applied in the domain of general knowledge reasoning with an excellent performance.For fine-grained professional fields,professional knowledge graphs can provide more accurate information in practical industrial scenarios.Based on an aviation assembly domain-specific knowledge graph,the article constructs a joint knowledge reasoning model,which combines a named entity recognition model and a subgraph embedding learning model.When performing knowledge reasoning tasks,the two models vectorize entities,relationships and entity attributes in the same space,so as to share parameters and optimize learning efficiency.The knowledge reasoning model,which provides intelligent question answering services,is able to reduce the assembly error rate and improve the assembly efficiency.The system can accurately solve general knowledge reasoning problems in the assembly process in actual industrial scenarios of general assembly and component assembly under interference-free conditions.Finally,this paper compares the proposed knowledge reasoning model based on knowledge representation learning and the question-answering system based on large-scale pre-trained models.In the application scenario of system functional testing in general assembly,the joint model attains an accuracy rate of 95%,outperforming GPT with 78%accuracy and enhanced representation through knowledge integration with 71%accuracy.

关键词： intelligent manufacturing knowledge graph aviation assembly knowledge representation knowledge-based question an-swering

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Mechanical property of cylindrical sandwich shell with gradient core of entangled wire mesh

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Defence Technology（防务技术） 2024年第1期31卷 510-522页

作者： Xin xue Chao Zheng Fu-qiang Lai xue-qian Wu Institute of Metal-rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou350116China Fujian Metallurgical Industry Design Institute Fuzhou350116China

To explore the wide-frequency damping and vibration-attenuation performances in the application of aerospace components,the cylindrical sandwich shell structure with a gradient core of entangled wire mesh was proposed in this paper.Firstly,the gradient cores of entangled wire mesh in the axial and radial directions were prepared by using an in-house Numerical Control weaving machine,and the metallurgical connection between skin sheets and the gradient core was performed using vacuum brazing.Secondly,to investigate the mechanical properties of cylindrical sandwich shells with axial or radial gradient cores,quasi-static and dynamic mechanical experiments were carried out.The primary evaluations of mechanical properties include secant stiffness,natural frequency,Specific Energy Absorption(SEA),vibration acceleration level,and so on.The results suggest that the vibration-attenuation performance of the sandwich shell is remarkable when the high-density core layer is at the end of the shell or abuts the inner skin.The axial gradient material has almost no influence on the vibration frequencies of the shell,whereas the vibration frequencies increase dramatically when the high-density core layer approaches the skin.Moreover,compared to the conventional sandwich shells,the proposed functional grading cylindrical sandwich shell exhibits more potential in mass reduction,stiffness designing,and energy dissipation.

关键词： Entangled wire mesh Gradient cylindrical sandwich shell Vacuum brazing Secant stiffness Damping

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Identification of anti-gastric cancer effects and molecular mechanisms of resveratrol: From network pharmacology and bioinformatics to experimental validation

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 493-513页

作者： Ying-qian Ma Ming Zhang Zhen-Hua Sun Hong-Yue Tang Ying Wang Jiang-xue liu Zhan-xue Zhang Chao Wang Department of Oncology Hebei General HospitalShijiazhuang 050051Hebei ProvinceChina School of Graduate Studies Hebei Medical UniversityShijiazhuang 050017Hebei ProvinceChina Clinical Medical Research Center Hebei General HospitalShijiazhuang 050051Hebei ProvinceChina Department of Gastrointestinal Surgery Second Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina

BACKGROUND Gastric cancer(GC)is one of the most aggressive malignancies with limited therapeutic options and a poor prognosis.Resveratrol,a non-flavonoid poly-phenolic compound found in a variety of Chinese medicinal materials,has shown excellent anti-GC effect.However,its exact mechanisms of action in GC have not been clarified.AIM To identify the effects of resveratrol on GC progression and explore the related molecular mechanisms.METHODS Action targets of resveratrol and GC-related targets were screened from public databases.The overlapping targets between the two were confirmed using a Venn diagram,and a“Resveratrol-Target-GC”network was constructed using Cyto-scape software version 3.9.1.The protein-protein interaction(PPI)network was constructed using STRING database and core targets were identified by PPI network analysis.The Database for Annotation,Visualization and Integrated A total of 378 resveratrol action targets and 2154 GC disease targets were obtained from public databases,and 181 intersection targets between the two were screened by Venn diagram.The top 20 core targets were identified by PPI network analysis of the overlapping targets.GO function analysis mainly involved protein binding,identical protein binding,cytoplasm,nucleus,negative regulation of apoptotic process and response to xenobiotic stimulus.KEGG enrichment analysis suggested that the involved signaling pathways mainly included PI3K-AKT signaling pathway,MAPK signaling pathway,IL-17 signaling pathway,TNF signaling pathway,ErbB signaling pathway,etc.FBJ murine osteosarcoma viral oncogene homolog(FOS)and matrix metallopeptidase 9(MMP9)were selected by differential expression analysis,and they were closely associated with immune infiltration.Molecular docking results showed that resveratrol docked well with these two targets.Resveratrol treatment arrested the cell cycle at the S phase,induced apoptosis,and weakened viability,migration and invasion in a dose-dependent manner.Furthermore,resveratrol could exhibit anti-GC effect by regula

关键词： Resveratrol Gastric cancer Network pharmacology Bioinformatics Molecular docking

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Current situation and prospect for the diagnosis and treatment of pediatric critical rare diseases in China

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儿科学研究(英文) 2024年第1期8卷 66-71页

作者： liu Yingchao qian Suyun Pediatric Intensive Care Unit Beijing Children’s Hospital Capital Medical University National Center for Children’s Health Beijing China

The onset of critical rare diseases (RDs) in children is rapid and dangerous, accompanied by a high mortality rate, which brings a heavy burden to both families and society. Multiple malformations, neuromuscular diseases, metabolic diseases, and heart diseases are the most common types of RDs in children of China, often manifesting with multiple organ dysfunction. At present, the diagnosis and treatment of critical RDs in children face challenges such as prolonged diagnosis time, a high misdiagnosis rate, limited treatment modalities, and a significant disease burden. However, with the progress in genetic testing technology, the establishment of multidisciplinary diagnosis and treatment platforms, and the implementation of relevant RD policies in China, children with critical RDs will received enhanced medical services, experience improved prognoses, and reintegrate into social life.

关键词： Children Critical Current situation Prospect Rare diseases

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Emerging perovskite materials for supercapacitors:Structure,synthesis,modification,advanced characterization,theoretical calculation and electrochemical performance

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Journal of Energy Chemistry 2024年第2期89卷 41-70,I0003页

作者： Yuehua qian Qingqing Ruan Mengda xue Lingyun Chen Department of Applied Chemistry School of Chemistry and Chemical EngineeringChongqing UniversityChongqing 401331China

As a new generation electrode materials for energy storage,perovskites have attracted wide attention because of their unique crystal structure,reversible active sites,rich oxygen vacancies,and good stability.In this review,the design and engineering progress of perovskite materials for supercapacitors(SCs)in recent years is summarized.Specifically,the review will focus on four types of perovskites,perovskite oxides,halide perovskites,fluoride perovskites,and multi-perovskites,within the context of their intrinsic structure and corresponding electrochemical performance.A series of experimental variables,such as synthesis,crystal structure,and electrochemical reaction mechanism,will be carefully analyzed by combining various advanced characterization techniques and theoretical calculations.The applications of these materials as electrodes are then featured for various SCs.Finally,we look forward to the prospects and challenges of perovskite-type SCs electrodes,as well as the future research direction.

关键词： Perovskite Modification engineering Oxygen vacancy Theoretical calculation methodology Supercapacitor

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Peroxisome proliferator-activated receptor gamma coactivator-1(PGC-1)family in physiological and pathophysiological process and diseases

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1249-1292页

作者： Lu qian Yanli Zhu Chao Deng Zhenxing Liang Junmin Chen Ying Chen xue Wang Yanqing liu Ye Tian Yang Yang Xi'an Key Laboratory of Cardiovascular and Cerebrovascular Diseases Xi'an No.3 HospitalThe Affiliated Hospital of Northwest UniversityNorthwest UniversityXi'an 710021China Xi'an Key Laboratory of Innovative Drug Research for Heart Failure Faculty of Life Sciences and MedicineNorthwest University229 Taibai North RoadXi'an 710069China Department of Cardiovascular Surgery The First Affiliated Hospital of Xi'an Jiaotong University277 Yanta West RoadXi'an 710061China Department of Cardiothoracic Surgery The First Affiliated Hospital of Zhengzhou University1 Jianshe EastZhengzhou 450052China Department of Hematology The First Affiliated Hospital of Xi'an JiaotongUniversity277 Yanta West RoadXi'an 710061China

Peroxisome proliferator-activated receptor gamma coactivator-1(PGC-1)family(PGC-1s),consisting of three members encompassing PGC-1a,PGC-1β,and PGC-1-related coactivator(PRC),was discovered more than a quarter-century ago.PGC-1s are essential coordinators of many vital cellular events,including mitochondrial functions,oxidative stress,endoplasmic reticulum homeostasis,and inflammation.Accumulating evidence has shown that PGC-1s are implicated in many diseases,such as cancers,cardiac diseases and cardiovascular diseases,neurological disorders,kidney diseases,motor system diseases,and metabolic disorders.Examining the upstream modulators and co-activated partners of PGC-1s and identifying critical biological events modulated by downstream effectors of PGC-1s contribute to the presentation of the elaborate network of PGC-1s.Furthermore,discussing the correlation between PGC-1s and diseases as well as summarizing the therapy targeting PGC-1s helps make individualized and precise intervention methods.In this review,we summarize basic knowledge regarding the PGC-1s family as well as the molecular regulatory network,discuss the physio-pathological roles of PGc-1s in human diseases,review the application of PGC-1s,including the diagnostic and prognostic value of PGC-1s and several therapies in pre-clinical studies,and suggest several directions for future investigations.This review presents the immense potential of targeting PGC-1s in the treatment of diseases and hopefully facilitates the promotion of PGC-1s as new therapeutic targets.

关键词： diseases life precise

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In vivo imaging reveals a synchronized correlation among neurotransmitter dynamics during propofol and sevoflurane anesthesia

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Zoological Research 2024年第3期45卷 679-690页

作者： Gao-Lin Qiu Li-Jun Peng Peng Wang Zhi-Lai Yang Ji-qian Zhang Hu liu Xiao-Na Zhu Jin Rao xue-Sheng liu Department of Anesthesiology First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui 230022China School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China

General anesthesia is widely applied in clinical practice.However,the precise mechanism of loss of consciousness induced by general anesthetics remains unknown.Here,we measured the dynamics of five neurotransmitters,includingγ-aminobutyric acid,glutamate,norepinephrine,acetylcholine,and dopamine,in the medial prefrontal cortex and primary visual cortex of C57BL/6 mice through in vivo fiber photometry and genetically encoded neurotransmitter sensors under anesthesia to reveal the mechanism of general anesthesia from a neurotransmitter perspective.Results revealed that the concentrations of γ-aminobutyric acid,glutamate,norepinephrine,and acetylcholine increased in the cortex during propofol-induced loss of consciousness.Dopamine levels did not change following the hypnotic dose of propofol but increased significantly following surgical doses of propofol anesthesia.Notably,the concentrations of the five neurotransmitters generally decreased during sevoflurane-induced loss of consciousness.Furthermore,the neurotransmitter dynamic networks were not synchronized in the non-anesthesia groups but were highly synchronized in the anesthetic groups.These findings suggest that neurotransmitter dynamic network synchronization may cause anesthetic-induced loss of consciousness.

关键词： General anesthesia Loss of consciousness In vivo neurotransmitter imaging Medial prefrontal cortex Primary visual cortex

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