Role of Subordinate Phases on the Dry Impact‑Abrasion Behavior of Low Chromium Cast Iron

Yu Pei,Renbo Song,Yi Li,Zhiyang Zhao,Yingchao Zhang 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.12

In order to study the resistance mechanism of materials having high resistance to impact-abrasion, synergistic effect ofsubordinate phases of 2.20 wt%C–3.45 wt%Cr–3.06 wt%Mn–1.32 wt%Si–0.51 wt%Cu–0.31 wt%Ni–0.002 wt%B cast ironwas investigated under dry impact-abrasion. Subordinate phases consist of graphite, secondary precipitates and retainedaustenite. Results show that the synergistic effect of above subordinate phases can prevent matrix and carbide from peelingoff, and minimize the damage of carbide to matrix. This effect reduces the depth and width of groove from 7 to 1.2 μm andfrom 14 to 2.5 μm respectively. Above significant improvement is owing that: (1) Graphite can disperse external/internalstress, and fill carbide peeling pits. (2) Secondary precipitates, such as [Fe, Ni] and [Cr, Ni], can disperse the concentratedstress of carbide, inhibiting peeling. (3) Retained austenite can disperse the internal concentrated stress which is transferredfrom the carbide and fine precipitates to matrix.

A Parallel-Structure-Based Sliding Mode Control for Trajectory Tracking of a Quadrotor UAV

Yu Hei-Pei,Wang Minyi,Yang Jiaqianhao,Xiong Jing-Jing 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.5

In this paper, aiming at the problem of incomplete yaw angle working range in a class of sliding mode control for quadrotor unmanned aerial vehicle (UAV), a parallel-structure-based sliding mode control (PSMC) method is proposed. Firstly, the dynamic model of the quadrotor UAV is considered to be composed of fully actuated subsystem and underactuated subsystem. For the fully actuated subsystem, the regular sliding mode manifold is used to design the controller. For the underactuated subsystem, the coordinate transformation of the error is taken into account in the sliding mode manifold. The coefficients of the sliding mode manifold can be obtained by the Hurwitz stability analysis. In addition, the stabilities of two subsystems are demonstrated by Lyapunov theory. Finally, comparative simulation results show that the PSMC not only improve the working range of yaw angle, but also illustrate the effectiveness of the proposed control method.

The seasonal detection of AcSBV (Apis cerana sacbrood virus) prevalence in Taiwan

Yu-Shin Nai,Chong-Yu Ko,Pei-Shou Hsu,Wen-Shi Tsai,Yue-Wen Chen,Meng-Hao Hsu,I-Hsin Sung 한국응용곤충학회 2018 Journal of Asia-Pacific Entomology Vol.21 No.1

The epizootic disease caused by Apis cerana sacbrood virus (AcSBV) occurred in Eastern hive bee, A. cerana, since2015 in Taiwan. A large-scale survey of this disease from September and December 2016 in Taiwan was performedincluding symptom check and molecular identification in honey bees of A. cerana hives and several A. mellifera hives, which were co-cultured with A. cerana. Based on the nucleotide sequences of partial VP1, thephylogenetic analysis with those of the known AcSBV isolates revealed that most of AcSBV isolates from Taiwanwere closely relative to SBV-FZ and -JL isolates from China, whereas only one sample (N15-5-1) was in a distinctcluster, which was closely relative to SBV-LN from China too. The AcSBV prevalence was occurring in A. ceranahives in most areas of Taiwan except for those in Hualien and Pingtung Counties in Taiwan. Notably, the AcSBVprevalence rate showed the temporal increase from 47.1% to 69.6% within 4 months. In addition, 37.5% ofAcSBV prevalence rate was found in A. mellifera hives. It showed that A. mellifera was also susceptible to AcSBVinfection. The present results would provide the information on the epidemiology and for prospective research.

Complete ¹H-NMR and <SUP>13</SUP>C-NMR spectral assignment of five malonyl ginsenosides from the fresh flower buds of Panax ginseng

Yu-Shuai Wang,Yin-Ping Jin,Wei Gao,Sheng-Yuan Xiao,Yu-Wei Zhang,Pei-He Zheng,Jia Wang,Jun-Xia Liu,Cheng-He Sun,Ying-Ping Wang 고려인삼학회 2016 Journal of Ginseng Research Vol.40 No.3

Background: Ginsenosides are the major effective ingredients responsible for the pharmacological effects of ginseng. Malonyl ginsenosides are natural ginsenosides that contain a malonyl group attached to a glucose unit of the corresponding neutral ginsenosides. Methods: Medium-pressure liquid chromatography and semipreparative high-performance liquid chromatography were used to isolate purified compounds and their structures determined by extensive one-dimensional- and two-dimensional nuclear magnetic resonance (NMR) experiments. Results: A new saponin, namely malonyl-ginsenoside Re, was isolated from the fresh flower buds of Panax ginseng, along with malonyl-ginsenosides Rb1, Rb2, Rc, Rd. Some assignments for previously published ¹H- and <SUP>13</SUP>C-NMR spectra were found to be inaccurate. Conclusion: This study reports the complete NMR assignment of malonyl-ginsenoside Re, Rb₁, Rb₂, Rc, and Rd for the first time.

Basic, HCC basic : PE-108 ; Progenitor cell-derived hepatocytes and their characteristics in human

( Pei Pei Hao ),( Mi Jin Lee ),( Goung Ran Yu ),( In Hee Kim ),( Dae Ghon Kim ) 대한간학회 2012 춘·추계 학술대회 (KASL) Vol.2012 No.-

Background: Hepatic progenitor cells (HPCs) are capable of differentiating along the hepatic lineage into hepatocytes or cholangiocytes (bile duct cells), hence play a critical role in the process of liver regeneration. Their biological discrimination and characterization are critical for therapeutic potential. Aims of this study is to establish progenitor cell-derived hepatocytes and to characterize their specific markers. Methods: Potential liver progenitor cells (HNK-1) were established and their various HPC protein expressions were investigated by immunoblotting, immunofluorescence and fluorescence-activated cell sorting (FACS) analyses, compared with those of other HCC cells. Immunohistochemistry was performed to detect these HPC antigen expression in the tissues of hepatic cirrhosis. Anchorage-independent growth and tumorigenicity were determined using soft agar and xenograft assay. Results: The HNK-1 cells highly expressed HPC markers such as EpCAM, CK7, CK19, AFP, CK8, CK18, EFNA1, and Thy1. Whereas, CD133 was barely expressed. In contrast, malignant Hep3B cells were positive in both EpCAM and CD133. Ductular reactions at the periphery of the cirrhotic nodules were immunohistochemically positive for these HPC markers. Sodium butyrate could induce hepatocyte-like morphological changes in HNK-1 cells, accompanying down-regulation of the hepatic progenitor cell markers (EpCAM, CK7, CK19, and EFNA1) and up-regulation of mature hepatocyte markers (albumin, CK8, and CK18) in both dose-dependent and time- dependent manners. Colony formation in vitro and tumorigenesis in vivo showed that there were no tumorigenesis capacity in EpCAM (+)/CD133(-) HNK1cells at the 0-2nd, 10th, 25th, and 50th passages, while the positive control EpCAM (+)/CD133(+) Hep3B cells could induce tumor in the mice model. Conclusions: Taken together, our results suggest that HNK1 cells are progenitor cell-derived hepatocytes and their stemmness- related markers EpCAM (+)/CD133(-) may be a distinguished marker for nonmalignant, progenitor cell-derived hepatocytes.

3D Trajectory Optimization for UAV-Aided IoT Data Collection in 3D Terrain with Heterogeneous Data Demand

Pei-Fa Sun(손페이파),Yu-Jae Song(송유재),Kang-Yu Gao(가오캉위),Yu-Kai Wang(왕우개),Sang-Woon Jeon(전상운) 한국통신학회 2024 한국통신학회 학술대회논문집 Vol.2024 No.1

Research on User-personalized Image Retrieval Method

Yu Song,Jing-fei Ren,Mao-Zhu Jin,Pei-Yu Ren 보안공학연구지원센터 2014 International Journal of Multimedia and Ubiquitous Vol.9 No.6

Basic, HCCbasic : PO-20 ; DUSP1 induces p53 target gene expression through p38MAPK/HSP27 pathway and tumor suppression in hepatocellular carcinoma

( Pei Pei Hao ),( Mi Jin Lee ),( Yun Peng Wang ),( Goung Ran Yu ),( In Hee Kim ),( Dae Ghon Kim ) 대한간학회 2012 춘·추계 학술대회 (KASL) Vol.2012 No.1

Background: Constitutive DUSP1 expression has been shown to be involved in cell cycle inhibition, apoptosis, and senescence. This study was aimed to examine whether DUSP1 functions as tumor suppressor in hepatocarcinogenesis and to explore underlying mechanism whereby DUSP1 suppresses hepatocarcinogenesis. Methods: Immunohistochemistry and real-time PCR analysis were performed in HCC tissues. Cellular localization of DUSP1 was detected by immunofluorescence. Cell proliferation was tested by MTT assay. Cell death and cell cycle were measured by FACS analysis. Apoptotic and kinase signaling were explored by western blot analysis. Tumorigenicity and survival analysis were tested by xenotransplant of SH-J1 cells stably expressing DUSP1 or infected with Ad-DUSP1 in mouse model. Phospho-related factors expression profile in DUSP1 stable cell lines as determined by phospho-kinase array. Results: The mRNA and protein expression level of DUSP1 was down-regulated in tumor than that of the corresponding non-tumor in HCC tissues. Cellular localization of DUSP1 showed that the endogenous DUSP1 and ectopic expression of GFP-tagged DUSP1 was mainly located in the nucleus. DUSP1 down-regulation was associated with reciprocal activation of ERK1/2 in HCC cell lines. DUSP1 was up-regulated in a dose dependent manner after parthenolide or doxorubicin treatment. DUSP1 over-expression was correlated with the increased susceptibility to apoptotic cell death through caspase activation. Ectopic DUSP1 over-expression resulted in the inhibitions of cell cycle progression, colony generation, and tumor growth in vitro and in vivo system. Furthermore, survival rate of mice xenoplanted with DUSP1 overexpressed HCC cells is significantly higher than control group. Inhibition of tumorigenic potential by DUSP1 may involve in p38MAPK- HSP27-P53 pathway. Conclusions: DUSP1 functions as a tumor suppressor during hepatocarcinogenesis, which seemed to be mainly associated with the activation of p53 target genes through p38MAPK/ HSP27 pathway.

Role of Salivary Immune Parameters in Patients With Primary Sjögren’s Syndrome

Yu-Hung Hung,Yung-Hung Lee,Pei-Pei Chen,Yuan-Zhao Lin,Chia-Hui Lin,Jeng-Hsien Yen 대한진단검사의학회 2019 Annals of Laboratory Medicine Vol.39 No.1

Background: Several factors, including clinical manifestations and laboratory data, have been used to evaluate the disease activity of Sjögren’s syndrome (SS). We investigated saliva indicators of disease activity in primary SS patients. Methods: We enrolled 138 Taiwanese patients with primary SS and 100 Taiwanese normal controls. Interleukin (IL)-6, IL-17A, tumor necrosis factor-alpha (TNF-α), and rheumatoid factor (RF)-IgA levels in saliva samples were measured using ELISA or fluorescent enzyme-linked immunoassay. Serum IgG, IgA, and IgM levels were measured by nephelometry. Erythrocyte sedimentation rate (ESR) was measured with an automatic ESR analyzer. The t-test and Pearson correlation test were used. Results: IL-6 level was higher in primary SS patients than in normal controls (14.23±14.77 vs 9.87±7.32, P=0.012), but there were no significant differences in IL-17A, TNF-α, and RF-IgA levels. In primary SS patients, IL-6 level correlated weakly with ESR and IgG levels (r=0.252, P=0.015, and r=0.248, P=0.017, respectively), and TNF-α level correlated weakly with IgG level (r=0.231, P=0.024). Conclusions: IL-6 may play a role in SS pathogenesis. Saliva IL-6 might be an indicator of disease activity in primary SS patients.

HCV : PE-108 ; Progenitor cell-derived hepatocytes and their characteristics in human

( Pei Pei Hao ),( Mi Jin Lee ),( Goung Ran Yu ),( N Hee Kim ),( Dae Ghon Kim ) 대한간학회 2012 춘·추계 학술대회 (KASL) Vol.2012 No.1

Background: Hepatic progenitor cells (HPCs) are capable of differentiating along the hepatic lineage into hepatocytes or cholangiocytes (bile duct cells), hence play a critical role in the process of liver regeneration. Their biological discrimination and characterization are critical for therapeutic potential. Aims of this study is to establish progenitor cell-derived hepatocytes and to characterize their specific markers. Methods: Potential liver progenitor cells (HNK-1) were established and their various HPC protein expressions were investigated by immunoblotting, immunofluorescence and fluorescence-activated cell sorting (FACS) analyses, compared with those of other HCC cells. Immunohistochemistry was performed to detect these HPC antigen expression in the tissues of hepatic cirrhosis. Anchorage-independent growth and tumorigenicity were determined using soft agar and xenograft assay. Results: The HNK-1 cells highly expressed HPC markers such as EpCAM, CK7, CK19, AFP, CK8, CK18, EFNA1, and Thy1. Whereas, CD133 was barely expressed. In contrast, malignant Hep3B cells were positive in both EpCAM and CD133. Ductular reactions at the periphery of the cirrhotic nodules were immunohistochemically positive for these HPC markers. Sodium butyrate could induce hepatocyte-like morphological changes in HNK-1 cells, accompanying down-regulation of the hepatic progenitor cell markers (EpCAM, CK7, CK19, and EFNA1) and up-regulation of mature hepatocyte markers (albumin, CK8, and CK18) in both dose-dependent and timedependent manners. Colony formation in vitro and tumorigenesis in vivo showed that there were no tumorigenesis capacity in EpCAM (+)/CD133(-) HNK1cells at the 0-2nd, 10th, 25th, and 50th passages, while the positive control EpCAM (+)/CD133(+) Hep3B cells could induce tumor in the mice model. Conclusions: Taken together, our results suggest that HNK1 cells are progenitor cell-derived hepatocytes and their stemmnessrelated markers EpCAM (+)/CD133(-) may be a distinguished marker for nonmalignant, progenitor cell-derived hepatocytes.