Double Modification of Electrode Surface for the Selective Detection of Epinephrine and Its Application to Flow Injection Amperometric Analysis

Xu, Guang-Ri,Qi, Xin-hua,Yang, Fengxia,Lee, Jae-Joon,Xu, Ming-Lu,Zhang, Yu-Ping,Kim, Sunghyun WILEY-VCH Verlag 2009 Electroanalysis Vol.21 No.22

<P>A glassy carbon electrode having two polymer layers has been applied to selectively detect epinephrine. The inner layer formed by electropolymerization of macrocyclic nickel complex functioned as an electrocatalyst for epinephrine oxidation and the outer layer composed of hydrolyzed polyurethane γ-benzyl L-glutamate as a screening layer. Differential pulse voltammetry showed almost 100% recovery of epinephrine even in 100-fold excess of interferents. When applied to a dual glassy carbon electrode as an amperometric detector in flow injection analysis, a linear response over 0.1 μM and 10 μM was obtained. Recovery tested for 5-fold diluted human urine samples was 97.5%.</P>

Improved Control Strategy Based on Space Vectors for Suppressing Grid-Side Current Harmonics in Three-Phase Current Source Rectifiers with a Hybrid Switch

Xu, Yan,Lu, Guang-Xiang,Jiang, Li-Jie,Yi, Gui-Ping The Korean Institute of Power Electronics 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.2

This paper analyses the harmonic pollution to power grids caused by several high-power rectifiers, summarizes the requirements for rectifiers in suppressing grid-side current harmonics and optimizes a new-type of current source PWM rectifier with a hybrid switch. The rectifier with a hybrid switch boasts significant current characteristics and cost advantages in the high-power area. To further enhance the working frequency of the current source rectifier with a hybrid switch for suppressing grid-side harmonics and reducing the inductance size, this paper proposes an optimal control strategy based on space vector. It also verifies that the optimal control strategy based on space vector can reduce the total harmonic distortion of the grid-side current of the rectifier with a hybrid switch via circuit simulation and experimental results.

Experimental behavior of circular flyash-concrete-filled steel tubular stub columns

Si-Ping Li,Yang Zhang,Guang-Yuan Fu,Chen-Jiang Yu,Bing Chen,She-Xu Zhao 국제구조공학회 2016 Steel and Composite Structures, An International J Vol.22 No.4

The paper presents an experimental study of the structural behavior of circular flyash-concrete-filled steel tubular stub columns under axial compressive loads. In this study, 90% and 100% by weight of the cement in the concrete core was replaced with flyash. Twenty-seven specimens were tested to study the influence of flyash content, wall thickness of the steel tube, and curing age on the ultimate capacity and confinement effect. The experimental results were compared with the design values calculated using AISC-LRFD (1999), ACI (1999), AIJ (1997) and Eurocode 4 (1994). From the experimental study, it was determined that the confinement effect of circular steel tubes filled with high content flyash concrete was better than that of specimens filled with ordinary Portland cement concrete. The 5.88-mm-thick steel tube filled with 100% flyash concrete was equivalent in strength to a steel tube filled with C30 concrete at 28 days.

Upregulation of STK15 in Esophageal Squamous Cell Carcinomas in a Mongolian Population

Chen, Guang-Lie,Hou, Gai-Ling,Sun, Fei,Jiang, Hong-Li,Xue, Jin-Feng,Li, Xiu-Shen,Xu, En-Hui,Gao, Wei-Shi,Cao, Jian-Ping Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.15

Background: The STK15 gene located on chromosome 20q13.2 encodes a centrosome-associated kinase critical for regulated chromosome segregation and cytokinesis. Recent studies have demonstrated STK15 to be significantly associated with many tumors, with aberrant expression obseved in many human malignancies. The purpose of this study was to investigate expression of STK15 in esophageal squamous cell carcinomas (ESCCs) in a Mongolian population. Methods: Two non-synonymous single nucleotide polymorphisms in the coding region of STK15, rs2273535 (Phe31Ile) and rs1047972 (Val57Ile) were assessed in 380 ESCC patients and 380 healthy controls. We also detected STK15 mRNA expression in 39 esophageal squamous cell carcinomas and corresponding adjacent tissues by real time PCR. Results: rs2273535 showed a significant association with ESCC in our Mongolian population (rs227353, P allele = 0.0447, OR (95%CI) = 1.259 (1.005~1.578)). Real time PCR analysis of ESCC tissues showed that expression of STK15 mRNA in cancer tissues was higher than in normal tissues (p = 0.013). Conclusions: Our study showed that functional SNPs in the STK15 gene are associated with ESCC in a Mongolian population and up-regulation of STK15 mRNAoccurs in ESCC tumors compared adjacent normal tissues. STK15 may thus have an important role in the prognosis of ESCC and be a potential therapeutic target.

Resveratrol Inhibits Oesophageal Adenocarcinoma Cell Proliferation via AMP-activated Protein Kinase Signaling

Fan, Guang-Hua,Wang, Zhong-Ming,Yang, Xi,Xu, Li-Ping,Qin, Qin,Zhang, Chi,Ma, Jian-Xin,Cheng, Hong-Yan,Sun, Xin-Chen Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.2

Resveratrol has been examined in several model systems for potential effects against cancer. Adenosine monophosphate-activated protein kinase (AMPK) is reported to suppress proliferation in most eukaryocyte cells. Whether resveratrol via AMPK inhibits proliferation of oesophageal adenocarcinoma cells (OAC) is unknown. The aim of this study was to determine the roles of AMPK in the protective effects of resveratrol in OAC proliferation and to elucidate the underlying mechanisms. Treatment of cultured OAC derived from human subjects or cell lines with resveratrol resulted in decreased cell proliferation. Further, inhibition of AMPK by pharmacological reagent or genetical approach abolished resveratrol-suppressed OAC proliferation, reduced the level of $p27^{Kip1}$, a cyclin-dependent kinase inhibitor, and increased the levels of S-phase kinase-associated protein 2 (Skp2) of $p27^{Kip1}$-E3 ubiquitin ligase and 26S proteasome activity reduced by resveratrol. Furthermore, gene silencing of $p27^{Kip1}$ reversed resveratrol-suppressed OAC proliferation. In conclusion, these findings indicate that resveratrol inhibits Skp2-mediated ubiquitylation and 26S proteasome-dependent degradation of $p27^{Kip1}$ via AMPK activation to suppress OAC proliferation.

Improved Control Strategy Based on Space Vectors for Suppressing Grid-Side Current Harmonics in Three-Phase Current Source Rectifiers with a Hybrid Switch

Yan Xu,Guang-xiang Lu,Li-jie Jiang,Gui-Ping Yi 전력전자학회 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.2

This paper analyses the harmonic pollution to power grids caused by several high-power rectifiers, summarizes the requirements for rectifiers in suppressing grid-side current harmonics and optimizes a new-type of current source PWM rectifier with a hybrid switch. The rectifier with a hybrid switch boasts significant current characteristics and cost advantages in the high-power area. To further enhance the working frequency of the current source rectifier with a hybrid switch for suppressing grid-side harmonics and reducing the inductance size, this paper proposes an optimal control strategy based on space vector. It also verifies that the optimal control strategy based on space vector can reduce the total harmonic distortion of the grid-side current of the rectifier with a hybrid switch via circuit simulation and experimental results.

Ce3+ triggers fenton-like processes in neutral solutions for effective catechol degradation

Xing Chen,Xu Liu,Hai-Bo Wang,Kang-Ping Cui,Rohan Weerasooriya,Shi-Long He,Guang-Hong Li,Jun Pan,Kai Zhou 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.1

Classical Fenton and Fenton-like processes destruct organic pollutants in water non-selectively to complete mineralization. However, the usage of classical Fenton or Fenton-like processes is often limited due to the narrow operational pH window, sludge accumulation, inefficient H₂O₂ and efficiency decline. To overcome these constraints, in this study, we used a homogeneous Fe<SUP>3+</SUP>-Ce<SUP>3+</SUP>-H₂O₂ Fenton-like process to degrade catechol at different experimental conditions. At pH 7, almost 97% of 10 mM catechol can be destructed within 60 min while the degradation by Classical Fenton or Fe<SUP>3+</SUP>-H₂O₂ Fenton-like process only 36.2% and 23.7%. The resultant solution after the degradation contains only traces of cerium ions. The sludge created by the process was extensively characterized by FTIR and XPS spectroscopy to elucidate the fate of cerium ions. Electron spin resonance (ESR) data confirmed •OH as the major free radical in Fe<SUP>3+</SUP>-Ce<SUP>3+</SUP>-H₂O₂ process. Our Fenton-like process widens the optimal pH values to neutral condition.

Three‑dimensional magnetic field analytical model‑based electromagnetic environment assessment of WPT systems

Bo Wang,Ping-an Tan,Xu Shangguan,Guang Tan,Xining Xu,Yanming Wu 전력전자학회 2024 JOURNAL OF POWER ELECTRONICS Vol.24 No.2

Electromagnetic environment assessment is an important step in the design process of a wireless power transfer (WPT) system to ensure that it complies with electromagnetic radiation standards. Electromagnetic environment assessment usually requires an effective magnetic field analytical model. However, the traditional magnetic field analytical model does not consider the impact of shielding media on the external electromagnetic environment of the WPT system. Therefore, based on subdomain analysis technology in the Cartesian coordinate system, this paper establishes a three-dimensional magnetic field analytical model that comprehensively considers coil parameters, passive shielding media, and active shielding coils. To solve the problem of re-dividing various regions when migrating, a misalignment parameter was introduced in the modeling analysis. In addition, an efficient active shielding coil modeling method is proposed based on electromagnetic theory, which reduces the analytical calculation time of the model. Finally, a 200 W WPT system electromagnetic environment assessment platform that includes both active and passive shielding is built. Under different misalignment and transmission distance conditions, the maximum error of the model calculation and finite element analysis (FEA) is less than 3%, and the maximum error of the model calculation and measurement values is less than 8%. Research results verify the accuracy of the proposed three-dimensional magnetic field analytical model and the effectiveness of the shielding measures. This paper lays a theoretical foundation for the electromagnetic environment assessment of WPT systems and the pre-design of shielding measures.

Cytokeratin 15 is an Effective Indicator for Progression and Malignancy of Esophageal Squamous Cell Carcinomas

Shen, Yu-Hong,Xu, Cui-Ping,Shi, Zhi-Meng,Zhang, Yan-Jiao,Qiao, Ya-Guang,Zhao, He-Ping Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.9

Purpose: To compare the expression level of CK 15 in normal esophageal and esophageal squamous-cell carcinoma (ESCC) tissues and analyse possible functions of CK15 in occurrence and development. Materials and Methods: Immunohistochemistry was used to compare CK14, CK15 and proliferating cell nuclear antigen (PCNA) expression levels in ESCCs. Expression level of CK15 was also assessed by Western blotting. In addition, levels of CK15, cytokeratin 19 fragment antigen 21-1 (CYFRA21-1) and PCNA were detected in serum by enzymelinked immunosorbent assay (ELISA) and chemiluminescence methods. Relationships between clinicopathological parameters and CK14 and CK15 expression were then analyzed. Results: According to immunohistochemistry, in esophageal and intraepithelial neoplasia (SIN) tissues, the expression of CK14, CK15 and PCNA localized to basal layer of the epithelium. CK14 and CK15 levels were higher in normal esophageal squamous epithelial tissue than in SIN and ESCC, and greater in highly differentiated than poorly differentiated carcinoma tissue. By Western blotting, we found more pronounced expression of CK15 in normal esophageal tissue, compared with carcinoma tissue. The specificity of changed CK15 and CYFRA21-1 expression was respectively 90.0% and 96.7% in serum of ESCC patients. Joint detection could improve the sensitivity of esophageal carcinoma diagnosis. Relationships between CK14, CK15 expression and clinical parameters were not statistically significant (P>0.05). Postoperative survival in patients of CK14, CK15 positive expression was longer than with negative expression ($x^2=4.35$, P=0.037; $x^2=9.852$, P=0.002). Conclusions: CK15 expression decreased in esophageal squamous cell carcinoma tissue and serum of esophageal squamous carcinoma patients. We infer that CK15 may play an important role for the occurrence and development of esophageal squamous-cell carcinoma. In the future, CK15 may be used for the diagnosis, treatment and prognostic evaluation of esophageal squamous-cell carcinoma.

Development of AFLP and SCAR Markers Linked to a Recessive Genic Male Sterile Gene (Bnms3) in Rapeseed for Marker-assisted Selection

Gui Chun Wang,Jun Ping He,Deng Feng Hong,Yan Zhou Xie,Zheng Hua Xu,Ping Wu Liu,Guang Sheng Yang 한국유전학회 2007 Genes & Genomics Vol.29 No.4

9012AB is a recessive genic male sterility (RGMS) line in rapeseed, of which the male sterility is controlled by two pairs of recessive duplicate male sterile genes (Bnms3 and Bnms4) interacting with a recessive epistatic suppressor gene (esp). The recessive homozygosity at the esp locus (espesp) can suppress the expression of the recessive male sterility trait in homozygous plants (Bnms3Bnms3Bnms4Bnms4) and result in fertility restoration. A F2 population of 188 plants, derived from self-pollinated progenies of a 9012 AB fertile plants (BnMs3Bnms3Bnms4Bnms4EspEsp), was conducted to identify molecular markers linked to the recessive male sterility gene (Bnms3). By amplified fragment length polymorphism (AFLP) assay combining with bulked segregant analysis (BSA), 13 markers linked to Bnms3 were identified. Linkage analysis indicated that 13 AFLP markers were tightly linked to the Bnms3 gene with a genetic distance varying from 1.3 cM to 7.1 cM. Among them, one marker was co-dominant marker, 6 markers were in coupling phase with Bnms3, and the others were in repulsion phase with Bnms3 gene, One AFLP marker with a genetic distance of 1.4cM was further converted into a SCAR marker successfully, which have been applied in marker-assisted selection of RGMS lines and their temporary maintainers effectively.