Application of transient elastography in nonalcoholic fatty liver disease

Xinrong Zhang,Grace Lai-Hung Wong,Vincent Wai-Sun Wong 대한간학회 2020 Clinical and Molecular Hepatology(대한간학회지) Vol.26 No.2

Nonalcoholic fatty liver disease (NAFLD) is currently the most common chronic liver disease worldwide. Although it has become one of the leading causes of cirrhosis and hepatocellular carcinoma in the Western world, the proportion of NAFLD patients developing these complications is rather small. Therefore, current guidelines recommend noninvasive tests for the initial assessment of NAFLD. Among the available non-invasive tests, transient elastography by FibroScan® (Echosens, Paris, France) is commonly used by hepatologists in Europe and Asia, and the machine has been introduced to the United States in 2013 with rapid adoption. Transient elastography measures liver stiffness and the controlled attenuation parameter simultaneously and can serve as a one-stop examination for both liver steatosis and fibrosis. Liver stiffness measurement also correlates with clinical outcomes and can be used to select patients for varices screening. Although obesity is a common reason for measurement failures, the development of the XL probe allows successful measurements in the majority of obese patients. This article reviews the performance and limitations of transient elastography in NAFLD and highlights its clinical applications. We also discuss the reliability criteria for transient elastography examination and factors associated with false-positive liver stiffness measurements.

Numerical study of flow of Oldroyd-3-Constant fluids in a straight duct with square cross-section

Zhang, Mingkan,Shen, Xinrong,Ma, Jianfeng,Zhang, Benzhao The Korean Society of Rheology 2007 Korea-Australia rheology journal Vol.19 No.2

A finite volume method (FVM) base on the SIMPLE algorithm as the pressure correction strategy and the traditional staggered mesh is used to investigate steady, fully developed flow of Oldroyd-3-constant fluids through a duct with square cross-section. Both effects of the two viscoelastic material parameters, We and ${\mu}$, on pattern and strength of the secondary flow are investigated. An amusing sixteen vortices pattern of the secondary flow, which has never been reported, is shown in the present work. The reason for the changes of the pattern and strength of the secondary flow is discussed carefully. We found that it is variation of second normal stress difference that causes the changes of the pattern and strength of the secondary flow.

Numerical study of flow of Oldroyd-3-Constant fluids in a straight duct with square cross-section

Mingkan Zhang,Xinrong Shen,Jianfeng Ma,Benzhao Zhang 한국유변학회 2007 Korea-Australia rheology journal Vol.19 No.2

A finite volume method (FVM) base on the SIMPLE algorithm as the pressure correction strategy and the traditional staggered mesh is used to investigate steady, fully developed flow of Oldroyd-3-constant fluids through a duct with square cross-section. Both effects of the two viscoelastic material parameters, We and , on pattern and strength of the secondary flow are investigated. An amusing sixteen vortices pattern of the secondary flow, which has never been reported, is shown in the present work. The reason for the changes of the pattern and strength of the secondary flow is discussed carefully. We found that it is variation of second normal stress difference that causes the changes of the pattern and strength of the secondary flow.

Insights Into the BR2/PGP1-mediated Patterns for Shoot and Root Growth in Maize Early Seedling Development by Comparative Transcriptome Sequencing

Xiangge Zhang,Lanjie Zheng,Haojun Zhang,Xinrong Huang,Yinghong Liu,Junjie Zhang,Yu-Feng Hu,Hanmei Liu,Guowu Yu,Yangping Li,Yubi Huang 한국식물학회 2019 Journal of Plant Biology Vol.62 No.3

Plant shoot and root growth is regulated by multiplefactors, including the hormone auxin. A maize brachytic2(br2) mutant displays a shortened shoot and root with highauxin concentration in their apexes, where BR2 encodes anauxin transporter P-glycoprotein1 (PGP1). We employedcomparative transcriptome sequencing to explore the BR2/PGP1-mediated patterns for shoot and root growth amongbr2, wild type (WT), and hybrid F1 (br2 × WT). The resultsshow 352 genes in the br2 shoot and 234 genes in the br2root are differentially expressed compared to WT and F1. Zm00001d045203 and Zm00001d031562 were identified astwo auxin-responsive genes in both the shoot and root. TheZm00001d045203 gene is down-regulated in br2 and encodesan Aux/IAA inhibitor involved in the SCFTIR1/AFB-mediatedauxin signaling pathway. The up-regulated Zm00001d031562gene encodes a small GTPase belonging to the Rab/Yptfamily, which takes part in auxin-mediated responses inArabidopsis. Cytology analysis reveals that reduced cellelongation affects the shoot and root growth of br2. TheZm00001d043477 gene is down-regulated and encodes amember of the cellulose synthase protein family, possiblyreducing cell elongation in the br2 shoot and root. Theseresults reveal the specific regulation of auxin actions and cellresponses by BR2/PGP1.

Comparative Hot Workability Characteristics of an Al–Si/SiCp Aluminium Matrix Composite Hybrid Reinforced with Various TiB2 Additions

Xinrong Chen,Zhiming Xu,Dingfa Fu,Hui Zhang,Jie Teng,Fulin Jiang 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.6

Hot compression tests were conducted on Al–Si/SiCp + TiB2 hybrid aluminium matrix composites with various TiB2contentsat temperatures from 350 to 500 °C and strain rates from 0.001 to 1 s−1. The hot workability characteristics and deformationmechanisms were investigated by combining constitutive equations, processing maps and microstructural observationsthrough scanning electron microscopy and transmission electron microscopy measurements. The results showed that therewere small differences in the peak stresses when the contents of TiB2were 3% and 5%, while the peak stress increased whenthe content of TiB2reached 8%. The contents of TiB2had little influence on the activation energy but affected the processingmaps to a certain extent. The areas of the instability zones were observed to gradually increase with increased TiB2additions. The optimal deformation conditions of the studied materials migrated from a low temperature and high strain rate to a hightemperature and low strain rate with increasing TiB2content. In addition, the flow softening mechanism transformed fromdynamic recrystallization + dynamic recovery to dynamic recovery with increasing TiB2content.

Robust Key Agreement From Received Signal Strength in Stationary Wireless Networks

( Aiqing Zhang ),( Xinrong Ye ),( Jianxin Chen ),( Liang Zhou ),( Xiaodong Lin ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.5

Key agreement is paramount in secure wireless communications. A promising approach to address key agreement schemes is to extract secure keys from channel characteristics. However, because channels lack randomness, it is difficult for wireless networks with stationary communicating terminals to generate robust keys. In this paper, we propose a Robust Secure Key Agreement (RSKA) scheme from Received Signal Strength (RSS) in stationary wireless networks. In order to mitigate the asymmetry in RSS measurements for communicating parties, the sender and receiver normalize RSS measurements and quantize them into q-bit sequences. They then reshape bit sequences into new l-bit sequences. These bit sequences work as key sources. Rather than extracting the key from the key sources directly, the sender randomly generates a bit sequence as a key and hides it in a promise. This is created from a polynomial constructed on the sender`s key source and key. The receiver recovers the key by reconstructing a polynomial from its key source and the promise. Our analysis shows that the shared key generated by our proposed RSKA scheme has features of high randomness and a high bit rate compared to traditional RSS-based key agreement schemes.

Point In Triangle Testing Based Trilateration Localization Algorithm In Wireless Sensor Networks

( Aiqing Zhang ),( Xinrong Ye ),( Haifeng Hu ) 한국인터넷정보학회 2012 KSII Transactions on Internet and Information Syst Vol.6 No.10

Localization of sensor nodes is a key technology in Wireless Sensor Networks(WSNs). Trilateration is an important position determination strategy. To further improve the localization accuracy, a novel Trilateration based on Point In Triangle testing Localization (TPITL)algorithm is proposed in the paper. Unlike the traditional trilateration localization algorithm which randomly selects three neighbor anchors, the proposed TPITL algorithm selects three special neighbor anchors of the unknown node for trilateration. The three anchors construct the smallest anchor triangle which encloses the unknown node. To choose the optimized anchors, we propose Point In Triangle testing based on Distance(PITD) method, which applies the estimated distances for trilateration to reduce the PIT testing errors. Simulation results show that the PIT testing errors of PITD are much lower than Approximation PIT(APIT) method and the proposed TPITL algorithm significantly improves the localization accuracy.

Brain Imaging Study on the Pathogenesis of Depression & Therapeutic Effect of Selective Serotonin Reuptake Inhibitors

Meng Qi,Zhang Aixia,Cao Xiaohua,Sun Ning,Li Xinrong,Zhang YunQiao,Wang Yanfang 대한신경정신의학회 2020 PSYCHIATRY INVESTIGATION Vol.17 No.7

Objective Predefining the most effective treatment for patients with depressive disorders remains a problem. We will examine the differential brain regions of gray matter (GM) in major depressive disorder (MDD) patients and the relationship between changes in their volume and the efficacy of early antidepressant treatment using magnetic resonance imaging (MRI).Methods 159 never-medicated patients with first-episode MDD and 53 normal control subjects (NCs) were enrolled. The brains were scanned by MRI and measured with the 17-item Hamilton Depression Rating Scale (HAMD-17) at baseline and after 2 weeks of treatment with selective serotonin reuptake inhibitor (SSRI)s, and the non-responder group and responder group were obtained. The patients were analyzed by voxel-based morphological (VBM) and SPSS software. Receiver operator characteristics (ROC) analysis was performed for the difference between the responder group and the non-responder group in the differential brain regions, and Pearson correlations were computed between volume size and HAMD score reduction rate.Results Smaller GM volume of the right superior temporal gyrus (STG), and the orbital parts of the right medial frontal gyrus and right inferior frontal gyrus were observed in MDD versus the NCs. The non-responder group demonstrated a significant volume reduction at the right STG compared with the responders, but no corresponding change in orbital part of right medial frontal gyrus and right inferior frontal gyrus. ROC analysis showed that Accuracy=71.2%. There was a positive correlation between the STG gray matter volume and the HAMD-17 score reduction rate (r=0.347, p=0.002).Conclusion The study results confirmed the local changes in brain structure in MDD and may initially predict the early treatment response produced by SSRIs as antidepressants.

Numerical investigation on the effects of real industrial bleeding geometry in a high-speed compressor stage

Jinlan Gou,Yang Zhang,Xinrong Su,Xin Yuan 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.11

A bleeding system is necessary for gas turbines and may largely affect the compressor performance. In the existing literature the circumferentially uniform bleeding is widely studied; however, it is different from the industrial bleeding geometry and may not fully reflect the effects on the compressor. We conducted a numerical study to investigate the flow mechanism of the real industrial bleeding geometry in a single-stage high-speed axial compressor environment. Results show that bleeding effects increase the adiabatic efficiency and slightly reduce the total-to-static pressure ratio. Furthermore, it is discovered that a locally aperiodic flow field in the rotor passages is generated due to the real bleeding geometry. In the tip region the maximum incident angle difference can reach 1 degree. Locally aperiodic bleeding makes the tip leakage strength and blockage different in various rotor passages.

U-shaped relationship between urea level and hepaticU-shaped relationship between urea level and hepatic decompensation in chronic liver diseases decompensation in chronic liver diseases

Huapeng Lin,Grace Lai-Hung Wong,Xinrong Zhang,Terry Cheuk-Fung Yip,Ken Liu,Yee Kit Tse,Vicki Wing-Ki Hui,Jimmy Che-To Lai,Henry Lik-Yuen Chan,Vincent Wai-Sun Wong 대한간학회 2022 Clinical and Molecular Hepatology(대한간학회지) Vol.28 No.1

Background/Aims: We aimed to determine the association between blood urea level and incident cirrhosis, hepatic decompensation, and hepatocellular carcinoma in chronic liver disease (CLD) patients. Methods: The association between blood urea level and liver fibrosis/liver-related events were evaluated on continuous scale with restricted cubic spline curves based on generalized additive model or Cox proportional hazards models. Then, the above associations were evaluated by urea level within intervals. Results: Among 4,282 patients who had undergone liver stiffness measurement (LSM) by transient elastography, baseline urea level had a U-shaped association with LSM and hepatic decompensation development after a median follow-up of 5.5 years. Compared to patients with urea of 3.6–9.9 mmol/L, those with urea ≤3.5 mmol/L (adjusted hazard ratio [aHR], 4.15; 95% confidence interval [CI], 1.68–10.24) and ≥10 mmol/L (aHR, 5.22; 95% CI, 1.86–14.67) had higher risk of hepatic decompensation. Patients with urea ≤3.5 mmol/L also had higher risk of incident cirrhosis (aHR, 3.24; 95% CI, 1.50–6.98). The association between low urea level and incident cirrhosis and hepatic decompensation was consistently observed in subgroups by age, gender, albumin level, and comorbidities. The U-shaped relationship between urea level and LSM was validated in another population screening study (n=917). Likewise, urea ≤3.5 mmol/L was associated with a higher risk of incident cirrhosis in a territory-wide cohort of 12,476 patients with nonalcoholic fatty liver disease at a median follow-up of 9.9 years (aHR, 1.27; 95% CI, 1.03–1.57). Conclusions: We identified a U-shaped relationship between the urea level and liver fibrosis/incident cirrhosis/hepatic decompensation in patients with CLD.