Triffin Dilemma and International Monetary System : Evidence from Pooled Mean-Group Estimation

Long Fei Guan,Wee Yeap Lau 한국유통과학회 2017 한국유통과학회 학술대회 논문집 Vol.2017 No.-

This study utilizes the panel data set of four major international currencies, USD, JPY, EUR and GBP from 1973 to 2013 with Pooled Mean-Group (PMG) estimator, to re-examine whether Triffin dilemma still exists through investigating the relationship between the reserve share, current account balance and real effective exchange rate. The evidence from the result indicates that Triffin dilemma exists only in the long run, and shows that in the long-run, current account balance is proportionate to the increased real effective exchange rate while varies inversely with the reserve shares. However, the estimation for the short-run is not significant to prove the existence of Triffin dilemma. In addition, we investigated the non-dollar panel sample and found that the international monetary system still suffers from Triffin dilemma even without the dollar. To overcome Triffin dilemma, three steps are suggested to be taken and in the longer time, a supranational currency is used to replace all the currencies in the world.

Triffin Dilemma and International Monetary System : Evidence from Pooled Mean Group Estimation

Long-Fei Guan,Wee-Yeap Lau 한국유통과학회 2018 The Journal of Asian Finance, Economics and Busine Vol.5 No.2

This study is motivated based on concern from some renowned scholars and central bankers whom have raised the issue of the sustainability of the International Monetary System (IMS). Using the panel data set of four major international currencies, USD, JPY, EUR and GBP from 1973 to 2013 with Pooled Mean Group (PMG) estimator, to re-examine whether Triffin dilemma still exists through investigating the relationship between the reserve share, current account balance and real effective exchange rate. The evidence from the result indicates that Triffin dilemma exists only in the long run, and shows that in the long-run, current account balance is proportionate to the increased real effective exchange rate while varies inversely with the reserve shares. However, the estimation for the short-run is not significant to prove the existence of Triffin dilemma. In addition, we investigated the non-dollar panel sample and found that the international monetary system still suffers from Triffin dilemma even without the dollar. To overcome Triffin dilemma, immediate step such as having currency swap mechanism is recommended. In medium term, a multi-polar Monetary System is suggested, and in the longer time, a supranational currency will be used to replace all the currencies in the world.

Optimized Medium Improves Expression and Secretion of Extremely Thermostable Bacterial Xylanase, XynB, in Kluyveromyces Lactis

( Yin Tie ),( Li Li Miao ),( Fei Fei Guan ),( Gui Li Wang ),( Qing Peng ),( Bing Xue Li ),( Guo Hua Guan ),( Ying Li ) 한국미생물 · 생명공학회 2010 Journal of microbiology and biotechnology Vol.20 No.11

An extremely thermostable xylanase gene, xynB, from the hyperthermophilic bacterium Thermotoga maritima MSB8 was successful expressed in Kluyveromyces lactis. The response surface methodology (RSM) was also applied to optimize the medium components for the production of XynB secreted by the recombinant K. lactis. The secretion level (102 mg/l) and enzyme activity (49 U/ml) of XynB in the optimized medium (yeast extract, lactose, and urea; YLU) were much higher than those (56 mg/l, 16 U/ml) in the original medium (yeast extract, lactose, and peptone; YLP). The secretory efficiency of mature XynB was also improved when using the YLU medium. When the mRNA levels of 13 characterized secretion-related genes in the K. lactis cultured in YLP and YLU were detected using a semiquantitative RT-PCR method, the unfolded protein response (UPR)-related genes, including ero1, hac1, and kar2, were found to be up-regulated in the K. lactis cultured in YLU. Therefore, the nutrient ingredients, especially the nitrogen source, were shown to have a significant influence on the XynB secretory efficiency of the host K. lactis.

Breast Cancer Association Studies in a Han Chinese Population using 10 European-ancestry-associated Breast Cancer Susceptibility SNPs

Guan, Yan-Ping,Yang, Xue-Xi,Yao, Guang-Yu,Qiu, Fei,Chen, Jun,Chen, Lu-Jia,Ye, Chang-Sheng,Li, Ming Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.1

Background: Genome-wide association studies (GWAS) have identified various genetic susceptibility loci for breast cancer based mainly on European-ancestry populations. Differing linkage disequilibrium patterns exist between European and Asian populations. Methods: Ten SNPs (rs2075555 in COL1A1, rs12652447 in FBXL17, rs10941679 in 5p12/MRPS30, rs11878583 in ZNF577, rs7166081 in SMAD3, rs16917302 in ZNF365, rs311499 in 20q13.3, rs1045485 in CASP8, rs12964873 in CDH1 and rs8170 in 19p13.1) were here genotyped in 1009 Chinese females (487 patients with breast cancer and 522 control subjects) using the Sequenom MassARRAY iPLEX platform. Association analysis based on unconditional logistic regression was carried out to determine the odds ratio (OR) and 95% confidence interval (95% CI) for each SNP. Stratification analyses were carried out based on the estrogen receptor (ER) and progesterone receptor (PR) status. Results: Among the 10 SNPs, rs10941679 showed significant association with breast cancer when differences between the case and control groups in this Han Chinese population were compared (30.09% GG, 45.4% GA and 23.7% AA; P = 0.012). Four SNPs (rs311499, rs1045485, rs12964873 and rs8170) showed no polymorphisms in our study. The remaining five SNPs showed no association with breast cancer in the present population. Immunohistochemical tests showed that rs2075555 was associated with ER status; the AA genotype showed greater association with ER negative than ER positive (OR = 0.54, 95% CI, 0.29-0.99; P = 0.046). AA of rs7166081 was also associated with ER status, but showed a greater association with ER positive than negative (OR = 1.59, 95% CI = 1.04-2.44; P = 0.031). However, no significant associations were found among the SNPs and PR status. Conclusion: In this study using a Han Chinese population, rs10941679 was the only SNP associated with breast cancer risk, indicating a difference between European and Chinese populations in susceptibility loci. Therefore, confirmation studies are necessary before utilization of these loci in Chinese.

Study on maximizing catalytic performance of cobalt(II) 5,10,15, 20-tetrakis(4-pyridyl)porphyrin for cyclohexane oxidation

Xian-Fei Huang,Guang-Ping Yuan,Guan Huang,Su-Juan Wei 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.77 No.-

Aiming at the most enhancing the catalytic performance of simple and cheap cobalt(II) 5,10,15,20-tetrakis(4-pyridyl)porphyrin (Co TPyP), guided by the nowadays-advanced various technologies, Co TPyP wasanchored onto nanoporous bar with thiol-functionalized silica (npb-SiO2-SH). The resulting npb-SiO2-SCoTPyP catalyst was characterized using various techniques, determining its structure. The total surfacearea ratios (TSAR) of the immobilized cobalt porphyrin to the npb-SiO2-SH, and the catalytic cyclohexaneoxidation reaction conditions were at the same time optimized via Response Surface Methodology(RSM). Compared with those obtained from traditional optimizing method (TOM), on average, RSM couldenhance as high as more than 60% catalyst turnover frequency (TOF) and yields of cyclohexanone andcyclohexanol (KA oil). The anchored 0.05 mg Co TPyP could catalyze the oxidation of 200 mL ofcyclohexane, under not using any solvents and additives, offering 2.5106 1/h of TOF, and 19% of yields. The npb-SiO2-S (20%-0.0438)-Co TPyP catalyst showed better reusability, excellent catalytic

In-Situ Synthesis of Highly Efficient Direct Z-Scheme Cu3P/g-C3N4 Heterojunction Photocatalyst for N2 Photofixation

Yuanhao Guan,Shaozheng Hu,Ping Liang,Yanfeng Zhao,Fei Wang,Xiaoxue Kang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.7

"In this work, a highly efficient p-type Cu3P/n-type g-C3N4 heterojunction photocatalyst was synthesized in situ. XRD, UV–Vis, N2 adsorption, TEM, XPS, PL, and EIS are used to characterize the as-prepared catalysts. The results show that Cu3P nanoparticles are highly dispersed onto the g-C3N4 surface, which obviously promotes the separation rate of electrons and holes. The charge transfer between Cu3P and g-C3N4 follows the ""Z-scheme"" mechanism. The as-prepared Cu3P/g-C3N4 heterojunction photocatalyst displays the ammonium ion production rate of 7.5 mg L -1 h -1 g cat -1, which is 28.8 times higher than that of neat g-C3N4, as well as good catalytic stability. The possible reaction mechanism is proposed."

Transverse Flexural Behaviour of Steel-Engineering Cementitious Composites (ECC) Composite Deck under Negative and Positive Bending Forces

Yanhua Guan,Jiajie Wu,Renjuan Sun,Hongzhi Zhang,Yanqiu Hu,Fei Wang 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.8

Orthotropic steel bridge deck system usually consists of an orthotropic steel deck and an asphalt overlay. Fatigue cracks of the orthotropic steel deck and premature damage of the asphalt overlay are frequently reported for such system. Engineering cementitious composites (ECC) was therefore proposed to replace the asphalt overlay to address the aforementioned issues. The current study presents an investigation on the transversal flexural behaviour of the ECC under bending forces. Influence of the bending force direction, cover thickness, the number of longitudinal reinforcement steel bars on the flexural performance was revealed. Responses with regard to the load-deflection curve, failure mode, the ultimate capacity, the cracking behaviour, the interfacial slip between ECC and steel deck and the nominal cracking stresses were analysed. The results showed that the load-deflection response under both negative and positive bending forces exhibits elastic stage, crack-developing stage and yield stage. Compared with the reinforcement ratio, cover thickness plays a more significant role on the flexural performances. When the cover thickness decreases from 35 mm to 25 mm, the peak load increases by 21% − 25%. ECC maintains its feature of being ductile, with high tensile and compressive strain capacity in the composite slab. From the design point of view, reducing the cover thickness and increasing the reinforcement ratio can improve the ultimate load and cracking stress, and reduce the internal slip, strain and crack width of the composite slab. It is expected that the current study can provide basic knowledge to the design and application of the steel-ECC composite deck system.

Genetic variations in the bitter taste receptor gene TAS2R38 are related to cigarette smoking behavior in Han Chinese smokers

Qi Fei-Yan,Zhu Zhou-Hai,Li Meng,Guan Ying,Peng Qi-Yuan,Lu She-Ming,Liu Zhi-Hua,Wang Ming-Feng,Miao Ming-Ming,Chen Zhang-Yu,Li Xue-Mei,Bai Jie,Yao Jian-Hua 한국유전학회 2022 Genes & Genomics Vol.44 No.11

Background: Smoking behavior is influenced by multiple genes, including the bitter taste gene TAS2R38. It has been reported that the correlation between TAS2R38 and smoking behavior has ethnicity-based differences. However, the TAS2R38 status in Chinese smokers is still unclear. Objective: This study aims to investigate the possible relationship between genetic variations in TAS2R38 (A49P, V262A and I296V) and smoking behaviors in the Han Chinese population. Methods: The haplotype analyses were performed and smoking behavior questionnaire was completed by 1271 individuals. Genetic association analyses for smoking behavior were analyzed using chi-square test. Further, for investigating the molecular mechanism of TAS2R38 variants effect on smoking behavior, we conducted TAS2R38-PAV and TAS2R38-AVI expression plasmids and tested the cellular calcium assay by cigarette smoke compounds stimulus in HEK293. Results: Significant associations of genetic variants within TAS2R38 were identified with smoking behavior. We found a higher PAV/PAV frequency than AVI/AVI in moderate and high nicotine dependence (FTND ≥ 4; X2 = 4.611, 1 df, p = 0.032) and strong cigarette smoke flavor intensity preference (X2 = 4.5383, 1 df, p = 0.033) in participants. Furthermore, in the in vitro cellular calcium assay, total particle matter (TPM), N-formylnornicotine and cotinine, existing in cigarette smoke, activated TAS2R38-PAV but not TAS2R38-AVI-transfected cells. Conclusion: Our data highlights that genetic variations in TAS2R38 are related to smoking behavior, especially nicotine dependence and cigarette smoke flavor intensity preference. Our findings may encourage further consideration of the taste process to identify individuals susceptible to nicotine dependence, particularly Han Chinese smokers.

Failure Process of Composite Columns with Embedded I-section Steel under Elevated Temperature-Load Level Effects

Zhan-Fei Huang,Wee-Siang Toh,Kang-Hai Tan,Guan-Hwee Phng 한국강구조학회 2007 International Journal of Steel Structures Vol.7 No.3

This paper presents an experimental study for investigating the effects of load level on structural behaviour of fourunprotected, embedded I-section steel composite columns. Each column was subjected to a constant axial compression forceunder rising temperature. Two electric furnaces were used to aply four-face heating condition on the columns to aproximatea realistic fire. All columns were made of siliceous concrete of normal cylinder strength around 44 MPa. Numerical analysesThecolumn failure times were also compared with design code predictions from EC4 Pt.1.2. It shows that the failure times reducedlinearly under an increasing load level. It was observed that all specimens underwent concrete spalling at the mid-height zone.

A PPAR α Agonist Improves Diabetic Nephropathy in db/db Mice

( Cheol Whee Park ),( You Fei Guan ),( Matthew D Breyer ) 대한신장학회 2004 추계학술대회 초록집 Vol.23 No.2