Two New Species of Placolecis (Lichenized Ascomycota) from China

( An Cheng Yin ),( Xin Yu Wang ),( Dong Liu ),( Yan Yun Zhang ),( Mei Xia Yang ),( Li Juan Li ),( Li Song Wang ) 한국균학회 2019 Mycobiology Vol.47 No.4

Two new species of the lichen genus Placolecis are discovered in China, namely P. kunmingensis An. C. Yin & Li S. Wang and P. sublaevis An. C. Yin & Li S. Wang. The new combination P. loekoesiana (S.Y. Kondr., Farkas, J.J. Woo & Hur) An. C. Yin is proposed. Placolecis kunmingensis is characterized by having simple, spherical or ellipsoid, hyaline spores, and pear-shaped pycnidia; while P. sublaevis can be distinguished by its thallus forming larger aggregations with slightly flattened lobes at the thallus margin, and urn-shaped pycnidia. Descriptions, a phylogenetic tree and a key are provided for all the known Placolecis species in China.

The Einstein-K\"ahler metrics onHua domain

An Wang,Weiping Yin 대한수학회 2003 대한수학회지 Vol.40 No.4

In this paper we describe the Einstein-K"ahler metric for theCartan-Hartogs of the first type which is the special case of theHua domains. Firstly, we reduce the Monge-Amp` ere equation forthe metric to an ordinary differential equation in the auxiliaryfunction X=X(z,w)=|w|^2[det(I-ZZ^T)]^{-frac{1}{K}}(see below).This differentialequation can be solved to give an implicit function in X.Secondly, we get the estimate of the holomorphic section curvatureunder the complete Einstein-K"ahler metric on this domain.

Adsorption of Pb(II) from aqueous solution to Ni-doped bamboo charcoal

Yin Wang,Xuejiang Wang,Xin Wang,Mian Liu,Zhen Wu,Lianzhen Yang,Siqing Xia,Jianfu Zhao 한국공업화학회 2013 Journal of Industrial and Engineering Chemistry Vol.19 No.1

Bamboo charcoal (BC) obtained by pyrolysis of Makino bamboo in the absence of oxygen was used as support for the preparation of Ni-doped adsorbent (Ni-BC). The low-cost composite was characterized and used as an adsorbent for Pb(II) removal from water. The results showed that both BET surface area and total pore volume of Ni-BC increased. The adsorption of Pb(II) strongly depended on solution pH,temperature and ionic strength. The adsorption isotherms followed Langmuir isotherm model well, and the maximum adsorption capacities of Pb(II) at 298 K were 25.0 and 142.7 mg/g for BC and Ni-BC,respectively. The adsorption processes were well fitted by pseudo-second-order kinetic model. Thermodynamic parameters showed that the adsorptions of Pb(II) onto both adsorbents were feasible,spontaneous, and exothermic under the studied conditions. The spent Ni-BC could be readily regenerated for reuse.

The effect of thiobarbituric acid on tyrosinase: inhibition kinetics and computational simulation.

Yin, Shang-Jun,Si, Yue-Xiu,Wang, Zhi-Jiang,Wang, Su-Fang,Oh, Sangho,Lee, Sanghyuk,Sim, Seon-Mi,Yang, Jun-Mo,Qian, Guo-Ying,Lee, Jinhyuk,Park, Yong-Doo Adenine Press 2011 Journal of biomolecular structure & dynamics Vol.29 No.3

<P>Tyrosinase plays various roles in organisms and much research has focused on the regulation of tyrosinase activity. We studied the inhibitory effect of thiobarbituric acid (TBA) on tyrosinase. Our kinetic study showed that TBA inhibited tyrosinase in a reversible noncompetitive manner (K(i) 5 14.0 ± 8.5 mM and IC?????? 5 8.0 ± 1.0 mM). Intrinsic and ANS-binding fluorescences studies were also performed to gain more information regarding the binding mechanism. The results showed that no tertiary structural changes were obviously observed. For further insight, we predicted the 3D structure of tyrosinase and simulated the docking between tyrosinase and TBA. The docking simulation was successful with significant scores (binding energy for AutoDock4: -5.52 kcal/mol) and suggested that TBA was located in the active site. The 11 ns molecular dynamics simulation convinced that the four HIS residues (residue numbers: 57, 90, 250, and 282) were commonly responsible for the interaction with TBA. Our results provide a new inhibition strategy that works using an antioxidant rather than targeting the copper ions within the tyrosinase active site.</P>

MicroRNA-214 Regulates the Acquired Resistance to Gefitinib via the PTEN/AKT Pathway in EGFR-mutant Cell Lines

Wang, Yong-Sheng,Wang, Yin-Hua,Xia, Hong-Ping,Zhou, Song-Wen,Schmid-Bindert, Gerald,Zhou, Cai-Cun Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.1

Patients with non-small cell lung cancer (NSCLC) who have activating epidermal growth factor receptor (EGFR) mutations derive clinical benefit from treatment with EGFR-tyrosine kinase inhibitors ((EGFR-TKIs)-namely gefitinib and erlotinib. However, these patients eventually develop resistance to EGFR-TKIs. Despite the fact that this acquired resistance may be the result of a secondary mutation in the EGFR gene, such as T790M or amplification of the MET proto-oncogene, there are other mechanisms which need to be explored. MicroRNAs (miRs) are a class of small non-coding RNAs that play pivotal roles in tumorigenesis, tumor progression and chemo-resistance. In this study, we firstly successfully established a gefitinib resistant cell line-HCC827/GR, by exposing normal HCC827 cells (an NSCLC cell line with a 746E-750A in-frame deletion of EGFR gene) to increasing concentrations of gefitinib. Then, we found that miR-214 was significantly up-regulated in HCC827/GR. We also showed that miR-214 and PTEN were inversely expressed in HCC827/GR. Knockdown of miR-214 altered the expression of PTEN and p-AKT and re-sensitized HCC827/GR to gefitinib. Taken together, miR-214 may regulate the acquired resistance to gefitinib in HCC827 via PTEN/AKT signaling pathway. Suppression of miR-214 may thus reverse the acquired resistance to EGFR-TKIs therapy.

The effect of Zn(2+) on Pelodiscus sinensis creatine kinase: unfolding and aggregation studies.

Wang, Su-Fang,Lee, Jinhyuk,Wang, Wei,Si, Yue-Xiu,Li, Caiyan,Kim, Tae-Rae,Yang, Jun-Mo,Yin, Shang-Jun,Qian, Guo-Ying Adenine Press 2013 Journal of biomolecular structure & dynamics Vol.31 No.6

<P>We studied the effects of Zn(2+) on creatine kinase from the Chinese soft-shelled turtle, Pelodiscus sinensis (PSCK). Zn(2+) inactivated the activity of PSCK (IC(50)?=?.079??.004?mM) following first-order kinetics consistent with multiple phases. The spectrofluorimetry results showed that Zn(2+) induced significant tertiary structural changes of PSCK with exposure to hydrophobic surfaces and that Zn(2+) directly induced PSCK aggregation. The addition of osmolytes such as glycine, proline, and liquaemin successfully blocked PSCK aggregation, recovering the conformation and activity of PSCK. We measured the ORF gene sequence of PSCK by rapid amplification of cDNA end and simulated the 3D structure of PSCK. The results of molecular dynamics simulations showed that eight Zn(2+) bind to PSCK and one Zn(2+) is predicted to bind in a plausible active site of creatine and ATP. The interaction of Zn(2+) with the active site could mostly block the activity of PSCK. Our study provides important insight into the action of Zn(2+) on PSCK as well as more insights into the PSCK folding and ligand-binding mechanisms, which could provide important insight into the metabolic enzymes of P. sinensis.</P>

A Generalized Framework of Dynamic Role Assignment for Robot Formation Control

Yin-Tien Wang,Yu-Cheng Chen 제어·로봇·시스템학회 2010 International Journal of Control, Automation, and Vol.8 No.6

A dynamic role assignment algorithm is proposed in the paper for formation control of multiple mobile robots. The goal of the algorithm is to reassign a role for each robot automatically during a formation is forming or switching. Many formation control systems have been successfully implemented and validated by supporting experimental results. Nevertheless, this research aims at providing an efficient algorithm of role assignment for a class of formation control systems employing the concept of combinational optimization problems. Specifically, by exploring spatial relationship between robots and information of obstacles surrounding the robots, a character cost function is found to represent the degree of difficulty for a robot been assigned a specified role in a formation. Instead of using complex cost minimization procedure, a solution is provided by calculating the largest value of character set fitness, and a new formation is selected for robots accordingly. The developed algorithm is applied to the formation control of a group omni-directional driven robots. Simulation and experimentation are performed with real platform to verify the proposed algorithm and the results show that the performance of the proposed dynamic role assignment algorithm is efficient for robot formation control.

Concentration-Controlled and Phytic Acid-Assisted Synthesis of Self-Assembled LiFePO4 as Cathode Materials for Lithium-Ion Battery

Yin Li,Keyu Zhang,Zhengjie Chen,Yunke Wang,Li Wang,Feng Liang,Yaochun Yao 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2020 NANO Vol.15 No.02

The olivine LiFePO4 with various morphologies and different growth lattice planes was prepared by a controllable hydrothermal method with changing precursor concentration and using phytic acid as phosphorus source. The microstructure, crystal orientation and electrochemical performance of the prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM) and charge–discharge tests. The results show that the morphologies of all samples change from spindle-like to hierarchical plate-like and then to long plate-like shape, and the main exposed facets transform from (100) to (001). This indicates that the precursor concentration and phytic acid play important roles in exposing facets and controlling the morphology of LiFePO4. In order to illustrate these phenomena, a reasonable assembly process is provided and the formation is explained. Li ion diffusion coefficient along [100] and [001] directions was calculated by using electrochemical impedance spectroscopy (EIS). The results show that the diffusion coefficient of (100) facet is higher than that of (001) facet, indicating a good electrochemical performance for (100) facet. In addition, the capacity test is carried out, which also confirms the above results. With the precursor concentration of 0.5 M, the obtained LiFePO4 with self-assembled hierarchical structure, smaller size and (100) facet shows the best electrochemical performance: 162.1 mAh/g at 0.1C and 112.4 mAh/g at 10 C. Using phytic acid as phosphorus source and controlling precursor concentration to prepare high performance LiFePO4 open up a new prospect for the production of cathode materials for lithium ion batteries.

Association of Matrix Metalloproteinase (MMP)-2 and -9 Expression with Extra-gastrointestinal Stromal Tumor Metastasis

Wang, Chao,Ma, Hong-Xi,Jin, Mei-Shan,Zou, Ya-Bin,Teng, Yong-Liang,Tian, Zhuang,Wang, Hai-Ying,Wang, Yin-Ping,Duan, Xiu-Mei Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.10

Matrix metalloproteinase (MMP)-2 and MMP-9 are important proteases involved in invasion and metastasis of various tumors. Extra-gastrointestinal stromal tumors (EGISTs) are rare neoplasms. This study was performed to assess MMP-2 and MMP-9 expression in EGIST tissue samples for association with clinicopathological data from the patients. Twenty-one surgical EGIST tissue specimens were collected for analysis of MMP-2 and MMP-9 expression using immunohistochemistry. MMP-2 and MMP-9 proteins were expressed in all of the epithelial cell types of EGISTs, whereas they were only expressed in 75% of the spindle cell type, although there was no statistically significant difference (p>0.05). Expression of MMP-2 and MMP-9 proteins was associated with tumor size, mitotic rate, tumor necrosis, and distant metastasis (p<0.05). MMP-2 expression was linked with MMP-9 levels (p<0.05). However, there was no correlation between MMP-9 expression and age, sex, primary site, or cell morphology in any of these 21 EGIST patients (p>0.05). Moreover, expression of MMP-2 and MMP-9 proteins increased with the degree of EGIST risk. This study provided evidence of an association of MMP-2 and MMP-9 expression with advanced EGIST behavior.

Study on the pore/scratch-strength response of ZrB2–SiC ceramic via laser processing

Wang Anzhe,Wang Shuai,Yin Huimin,Zhou Peng,Liu Dazhao 한국세라믹학회 2022 한국세라믹학회지 Vol.59 No.6

Defects, such as pores and scratches, are inevitably introduced during preparation and processing of ceramics. How they aff ect the mechanical properties of materials is worthy of attention. Here, artifi cial surface pores and notches introduced by femtosecond/nanosecond lasers are regarded as inherent pore- and scratch-like defects. Bending test results indicated that a small-sized fl aw with the length and depth of ~ 10 μm could lead to a strength reduction up to ~ 40% in sharp fl aw case, while only slight attenuation (< 10%) occurs in blunt fl aw case. Linear extrapolation result reveals that the maximum strength in notch cases, when the depth reaches the atomic scale, is ~ 34 GPa, which is in the range of the theoretical value of 24–48 GPa. Furthermore, the calculated critical fl aw size ( ac) may tend to be overestimated, given that the artifi cial defect, which is smaller than the ac value, also results in signifi cant strength decay. This study could provide guidance for strength evalu- ation and high-strength design of ceramics.