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Novel non-invasive score to predict cirrhosis in the era of hepatitis c elimination: A population study of ex-substance users in Singapore

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Hepatobiliary & Pancreatic Diseases International 2019年第2期18卷 143-148页

作者： Yue Zhao Prem Harichander Thurairajah Rahul Kumar Jessica Tan Eng Kiong Teo John chen Hsiang Department of Gastroenterology and Hepatology Changi General Hospital

Background: chronic hepatitis c infection is common among people with history of substance use. Liver fibrosis assessment is a barrier to linkage to care, particularly among those with history of substance users. The use of non-invasive scores can be helpful in predicting liver cirrhosis in the era of HcV elimination, especially in countries where transient elastography(TE) is not available. We compared the commonly used non-invasive scores with a novel non-invasive score in predicting liver cirrhosis in this population. Methods: HcV patients with history of substance use between 2011 and 2016 were analyzed. All patients had TE for liver fibrosis assessment. clinical performance of established non-invasive scores for fibrosis assessment and novel score were compared. Youden's index was used to determine optimal cut-off of the novel score. Results: A total of 579 patients were included. In multivariate logistic regression, cirrhosis on TE was associated with age( P = 0.002), aspartate aminotransferase(AST)( P = 0.004), and platelet count( P < 0.001), but not alanine aminotransferase(ALT)( P = 0.896). These form the components of modified AST-toplatelet ratio index(APRI) score. Modified APRI was superior to APRI in predicting cirrhosis(AUROc, 0.796 vs. 0.770, P = 0.007), but not fibrosis-4 score(FIB-4)( P = 1.00). Modified APRI at cut-off of 4 has sensitivity, specificity and negative predictive value(NPV) of 94.4%, 26.9% and 92.6%, respectively, and at 19, has sensitivity, specificity and positive predictive value(PPV) of 33.3%, 96.2% and 77.1%, respectively. FIB-4 has a NPV and PPV of 88.6%, 41.8% and 78.5%, 77.6%, at cut-off of 1.45 and 3.25, respectively. Using the cut-off of 4 and 14 for modified APRI, 32.5% of patients can be correctly classified and misses out only 5.6% of cirrhosis patients. conclusions: Modified APRI score is superior in predicting cirrhosis in HcV population, with 32.5% of the population being correctly classified using cut-off of 4 and 14.

关键词： Hepatitis c cirrhosis Fibrosis assessment AST-to-platelet ratio index Modified APRI Fibrosis-4 score

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A new clue for the pathogenesis of hepatitis c virus infection:Activation of the MAPK/ERK signaling initiated by envelope protein 2

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Science china(Life Sciences) 2003年第5期46卷 538-545页

作者：赵兰娟刘厚奇朱诗应冯根生戚中田 Department of Microbiology Second Military Medical University Shanghai 200433 China Department of Histology and Embryology Second Military Medical University Shanghai 200433 China Burnham Institute San Diego CA92037 USA

Since cell signal transduction plays an important role in disclosing the nature of human diseases, the pathogenesis of viruses may result from the disturbance of intracellular signal cascades caused by viral proteins. Hepatitis c virus (HcV) is a main causative agent of severe human liver disorders worldwide. So far, the mechanisms of HcV pathogenicity remain unclear. Envelope protein 2 (E2) of HcV is thought to be responsible for initiating virus attachment to host cells, which is a prerequisite of HcV infection. We assume that some early events of HcV pathogenic effects may result from the interaction of HcV E2 protein with its cellular receptor (human cD81), which could regulate cell proliferation and differentiation. To test this hypothesis, the effects of HcV E2 protein on MAPK/ERK pathway in Molt-4 and U937 cells with or without human cD81 expression were investigated. The results showed that HcV E2 protein could specifically activate the MAPK/ERK pathway, and such activation was inhibited by monoclonal antibodies against cD81 or HcV E2, serum antibodies from HcV infected patients, and upstream MEK1 inhibitor PD98059. Moreover, HcV E2-driven MAPK/ERK or downstream transcription factor Elk-1 activation was completely blocked in the presence of PD98059. These findings strongly suggest that the regulation of transmembrane signaling by HcV E2 protein via its receptor(s) on host cells might contribute to the development of HcV-related diseases.

关键词： hepatitis c virus, envelope protein 2, MAPK/ERK, signal transduction, pathogenesis.

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A cutting Force Prediction Model, Experimental Studies, and Optimization of cutting Parameters for Rotary Ultrasonic Face Milling of c/Sic composites

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APPLIED cOMPOSITE MATERIALS 2020年第4期27卷 407-431页

作者： Islam, Shafiul Yuan, Songmei Li, Zhen Beihang Univ Beijing Engn Technol Res Ctr High Efficient & Gre Sch Mech Engn & Automat Beijing 100191 Peoples R China

ceramic matrix composites of type c/Sic have great potential because of their excellent properties such as high specific strength, high specific rigidity, high-temperature endurance, and superior wear resistance. However, the machining of c/Sic is still challenging to achieve desired efficiency and quality due to their heterogeneous, anisotropic, and varying thermal properties. Rotary ultrasonic machining (RUM) is considered as a highly feasible technology for advanced materials. cutting force prediction in RUM can help to optimize input variables and reduce processing defects in composite materials. In this research, a mathematical axial cutting force model has been developed based on the indentation fracture theory of material removal mechanism considering penetration trajectory and energy conservation theorem for rotary ultrasonic face milling (RUFM) of c/Sic composites and validated through designed sets of experiments. Experimental results were found to be in good agreement with theoretically simulated results having less than 15% error. Therefore, this theoretical model can be effectively applied to predict the axial cutting forces during RUFM of c/Sic. The surface roughness of the workpiece materials was investigated after machining. The relationships of axial cutting force and surface roughness with cutting parameters, including spindle speed, feed rate, and cutting depth, were also investigated. In order to identify the influence of cutting parameters on the RUFM process, correlation analysis was applied. In addition, response surface methodology was employed to optimize the cutting parameters.

关键词： c Sic composites Rotary ultrasonic face milling A predictive cutting force model Surface roughness Optimization of cutting parameters

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Size effect of carbon fiber-reinforced silicon carbide composites (c/c-Sic): Part 2-tensile testing with alignment device

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JOURNAL OF THE EUROPEAN cERAMIc SOcIETY 2022年第4期42卷 1227-1237页

作者： Flauder, Stefan Bombarda, Ilaria D'Ambrosio, Roberto Langhof, Nico Lazzeri, Andrea Krenkel, Walter Schaffoener, Stefan Univ Bayreuth Ceram Mat Engn CME Prof Rudiger Bormann Str 1 D-95447 Bayreuth Germany IPCF CNR Ist & Processi Chimicofis Via G Moruzzi 1 I-56124 Pisa Italy Univ Pisa Dept Civil & Ind Engn Via Diotisalvi 2 I-56122 Pisa Italy

The appropriate assessment of mechanical properties is essential to design ceramic matrix composites. The size effect of strength plays a key role for the material understanding and the transfer from lab-scale samples to components. In order to investigate the size effect for carbon fiber-reinforced silicon carbon (c/c-Sic) under tensile load, a tensile testing with a minimum of deviation from the pure tensile loading is necessary. Hence, a hybrid edge/face-loading test device for self-alignment and centering of c/c-Sic tensile samples was developed, evaluated and proved to ensure pure tensile load. The mechanical analysis of more than 190 samples with two different cross-sections fabricated from the same material population revealed no significant difference in tensile strength. Although the volume under load was increased from 129 to 154 mm3, the tensile strengths of 162 +/- 7 and 164 +/- 6 MPa did not change. These results are discussed regarding the weakest link and energetic size effect approaches.

关键词： ceramic matrix composites (cMc) c c-Sic Tensile testing Size effect of strength Alignment device

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Genomic dissection and expression analysis of stress -responsive genes in c 4 panicoid models, Setaria italica and Setaria viridis

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JOURNAL OF BIOTEcHNOLOGY 2020年 318卷 57-67页

作者： Muthamilarasan, Mehanathan Singh, Roshan Kumar Suresh, Bonthala Venkata Rana, Sumi Dulani, Priya Prasad, Manoj Univ Hyderabad Sch Life Sci Dept Plant Sci Hyderabad 500046 Telangana India Natl Inst Plant Genome Res Aruna Asaf Ali Marg New Delhi 110067 India

The study reports the identification and expression profiling of five major classes of c 4 pathway-specific genes, namely, carbonic anhydrase (caH), phospho enol pyruvate carboxylase (PEPc), pyruvate orthophosphate dikinase (PPDK), NADP-dependent malate dehydrogenase (MDH) and NADP-dependent malic enzyme (NADP-ME), in the model species, Setaria italica and Setaria viridis . A total of 42 and 41 genes were identified in S. italica and S. viridis , respectively. Further analysis revealed that segmental and tandem duplications have contributed to the expansion of these gene families. RNA-Seq derived expression profiles of the gene family members showed their differential expression pattern in tissues and dehydration stress. comparative genome mapping and Ks dating provided insights into their duplication and divergence in the course of evolution. Expression profiling of candidate genes in contrasting S. italica cultivars subjected to abiotic stresses and hormone treatments showed distinct stress-specific upregulation of SiαcaH1 , SiβcaH5, SiPEPc2 , SiPPDK2 , SiMDH8, and SiNADP-ME5 in the tolerant cultivar. Overexpression of SiNADP-ME5 in heterologous yeast system enabled the transgenic cells to survive and grow in dehydration stress conditions, which highlights the putative role of SiNADP-ME5 in conferring tolerance to dehydration stress. Altogether, the study highlights key genes that could be potential candidates for elucidating their functional roles in abiotic stress response.

关键词： c 4 photosynthesis Expression profiling comparative mapping Evolution Foxtail millet ( Setaria italica ) Green foxtail ( Setaria viridis )

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c/Sb Superlattice-Like Films with High Thermal Stability and Low Power consumption for Phase-change Memory

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JOURNAL OF ELEcTRONIc MATERIALS 2022年第10期51卷 5594-5600页

作者： Zeng, Xiaotian Zhu, Xiaoqin Hu, Yifeng Song, Zhitang Jiangsu Univ Technol Sch Math & Phys Changzhou 213001 Jiangsu Peoples R China Chinese Acad Sci Shanghai Inst Microsyst & Informat Technol State Key Lab Funct Mat Informat Shanghai 200050 Peoples R China

The physical properties and device electrical properties of superlattice-like c/Sb phase change films are investigated. compared with Sb monolayer films, the superlattice-like c/Sb films have preferable thermal stability, including higher crystallization temperature, longer data life, and larger crystallization activation energy. As the thickness of the carbon layer increases, the band gap gradually increases. X-ray photoelectron spectroscopy results show that c-Sb bonds exist in the c/Sb superlattice-like films. X-ray diffraction and atomic force microscope results show that the addition of carbon inhibits the grain growth, making the grain size smaller and inhibiting the crystallization of Sb materials. Phase-change memory devices based on [c(6nm)/Sb(4nm)](8) superlattice-like films have smaller threshold voltages and lower power consumption compared to Sb films. In conclusion, c/Sb superlattice-like films have high thermal stability and low power consumption.

关键词： Phase-change memory c Sb superlattice-like film high thermal stability low power consumption

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combustion synthesis of c/MgAl2O4 composite powders using magnesium oxalate as carbon source

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INTERNATIONAL JOURNAL OF APPLIED cERAMIc TEcHNOLOGY 2019年第3期16卷 1253-1263页

作者： Lv, Lihua Xiao, Guoqing Ding, Donghai Ren, Yun Yang, Shoulei Yang, Pan Hou, Xing Xian Univ Architecture & Technol Coll Mat & Mineral Resources Xian Shaanxi Peoples R China

In order to solve the bottleneck problems including uniform distribution, and oxidation resistance of nano carbons in oxide ceramics, c/MgAl2O4 composite powders were prepared with Mgc2O4 center dot 2H(2)O, MgO2, Al2O3, and Al as raw materials via combustion method under argon atmosphere. The maximum adding amount of Mgc2O4 center dot 2H(2)O is 34.34 wt%. The phase compositions and microstructures of combustion products were characterized through X-ray diffraction (XRD), scanning electron microscope (SEM)/EDX, and Raman spectroscopy. The results showed that the phases of products are mainly composed of MgAl2O4 and carbon. The prepared MgAl2O4 has granular and rod-like morphologies, and the free carbon (1.172 wt%) exists between particles of MgAl2O4. Moreover, the addition of Fec2O4 as catalyst in raw materials ratio would be beneficial for improving crystallization of in situ carbon generated in the products. The oxidation activation energy of the prepared c/MgAl2O4 composite powders was calculated as 143.01 kJ/mol which was 22.17% higher than that of carbon black/MgAl2O4 powders (117.06 kJ/mol), suggesting that the c/MgAl2O4 composite powders prepared by combustion synthesis have excellent oxidation resistance.

关键词： c MgAl2O4 composite powders combustion synthesis microstructure

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Effect of the incorporation of Sic nanowire with double protective layers on Sic coating for c/c composites

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JOURNAL OF THE EUROPEAN cERAMIc SOcIETY 2023年第11期43卷 4636-4644页

作者： Xie, Aolin Zhang, Bei Ge, Yicheng Peng, Ke Xu, Ping Wang, Xiaodong Feng, Zhirong Yi, Maozhong Zhou, Zhe Cent South Univ State Key Lab Powder Met Changsha 410083 Peoples R China Changsha Univ & Sci & Technol Coll Mat Sci & Engn Changsha 410114 Hunan Peoples R China

To maintain the thermal stability of Sic nanowires during Sic coating fabrication process, carbon and Sic double protective layers were covered on the surface of nanowires. And Sic nanowires with double protective layers toughened Sic coating were prepared by pack cementation. The results showed that after introducing the Sic nanowires with double protective layers, the fracture toughness of the Sic coating was increased by 88.4 %. The coating protected c/c for 175 h with a mass loss of 3.67 %, and after 51 thermal shock cycles, the mass losses of the oxidized coating were 3.96 %. The double protective layers are beneficial to improve the thermal stability of nanowires, leading to good fracture toughness and thermal shock resistance of Sic coating. Sic nanowires consume the energy of crack propagation by fracture, pullout and bridging, leading to an increase in fracture toughness.

关键词： c c composites Sic nanowire-toughened Sic coating Double protective layers Fracture toughness Oxidation resistance

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Synthesis of c, Ag co-modified TiO₂ photocatalyst and its application in waste water purification

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APPLIED SURFAcE ScIENcE 2013年 271卷 276-283页

作者： Liu, Hui Dong, Xiaonan Li, Guangjun Su, Xing Zhu, Zhenfeng Shaanxi Univ Sci & Technol Sch Mat Sci & Engn Xian 710021 Peoples R China

Monodispersed c, Ag co-modified TiO2 microspheres were successfully synthesized through a two-step method. Firstly, monodisperse spherical TiO2 particles were obtained via controlled hydrolysis of TBOT (tetrabutyltitanate) in ethanol. Secondly, the c, Ag co-modified TiO2 microspheres were prepared through a simple calcination process, in which the AgNO3 and citric acid was used as Ag and c source, respectively. The physical and chemical properties of c, Ag co-modified TiO2 microspheres were carefully studied by using XRD, SEM, TEM, Raman, PL spectra and UV-vis diffuse reflectance spectra (DRS), while the chemical states of c and Ag were discussed via EDS (energy dispersive spectrometer) and XPS. The photocatalytic activity of the as-prepared products was evaluated by photocatalytic decolorization of Rhodamine B (Rh B) aqueous solution at ambient temperature under UV and visible-light irradiation. The photocatalytic activity research shows that, with the cooperation of two modified materials, c, Ag co-modified TiO2 microspheres exhibit enhanced photocatalytic activity both in ultraviolet and visible-light region compared with that of pure TiO2 and single Ag modified TiO2 microspheres. (c) 2013 Elsevier B.V. All rights reserved.

关键词： c Ag co-modified TiO2 microspheres Synthesis Photocatalysis

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cf4ocl: A c framework for OpencL

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ScIENcE OF cOMPUTER PROGRAMMING 2017年 143卷 9-19页

作者： Fachada, Nuno Lopes, Vitor V. Martins, Rui c. Rosa, Agostinho c. IST LARSyS ISR Av Rovisco Pais 1 P-1049001 Lisbon Portugal UTEC Univ Ingn & Tecnol Jr Medrano Silva 165 Lima Peru Univ Lisbon Fac Ciencias CMAF CIO Campo Grande P-1749016 Lisbon Portugal INESC TEC Campus FEUPRua Dr Roberto Frias P-4200465 Oporto Portugal

OpencL is an open standard for parallel programming of heterogeneous compute devices, such as GPUs, cPUs, DSPs or FPGAs. However, the verbosity of its c host API can hinder application development. In this paper we present cf4ocl, a software library for rapid development of OpencL programs in pure c. It aims to reduce the verbosity of the OpencL API, offering straightforward memory management, integrated profiling of events (e.g., kernel execution and data transfers), simple but extensible device selection mechanism and user-friendly error management. We compare two versions of a conceptual application example, one based on cf4ocl, the other developed directly with the OpencL host API. Results show that the former is simpler to implement and offers more features, at the cost of an effectively negligible computational overhead. Additionally, the tools provided with cf4ocl allowed for a quick analysis on how to optimize the application. (c) 2017 Elsevier B.V. All rights reserved.

关键词： OpencL c GPGPU High-performance computing Profiling

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