Multilocus Sequence Typing and Virulence Factors Analysis of Escherichia coli O157 Strains in China

Xiao W. Ji,Ya L. Liao,Ye F. Zhu,Hai G. Wang,Ling Gu,Jiang Gu,Chen Dong,Hong L. Ding,Xu H. Mao,Feng C. Zhu,Quan M. Zou 한국미생물학회 2010 The journal of microbiology Vol.48 No.6

Escherichia coli O157:H7, an important food-borne pathogen, has become a major public health concern worldwide. The aim of this study was to investigate the molecular epidemiologic feature of E. coli O157:H7strains in China. 105 E. coli O157:H7 isolates were collected from various hosts and places over 9 years. A multilocus sequence typing scheme (MLST) was applied for bacteria genotyping and polymerase chain reaction (PCR) was used for virulence factor identification. Seven new MLST sequence types (STs), namely ST836, ST837, ST838, ST839, ST840, ST841, and ST842 were identified, which grouped into two lineages. Phylogenetic analysis suggested that the most two frequent STs in China, ST837 and ST836, may be the derivatives of E. coli O157:H7 Sakai or E. coli O157:H7 EDL933. Geographical diversity and host variety of E. coli O157:H7 were observed in China. In addition, the different distribution of tccp was detected. The data presented herein provide new insights into the molecular epidemiologic feature of E. coli O157:H7, and aid in the investigation of the transmission regularity and evolutionary mechanism of E. coli O157:H7.

Key Features in the Operation of KSTAR

Jong-Gu Kwak,Oh, Y. K.,Kim, K. P.,Kim, S. W.,Hong, S. H.,Chu, Y.,Lee, H. J.,Kim, Y. O.,Kim, J.,Park, S. L.,Hahn, S. H.,Park, M. K.,Kim, H. K.,Bak, J. G.,Bae, Y. S.,Ko, W. H.,Lee, S. G.,Lee, J. H.,Jung IEEE 2012 IEEE transactions on plasma science Vol.40 No.3

<P>The Korea Superconducting Tokamak Advanced Research (KSTAR) device is aimed at advanced tokamak (AT) research. Three years have passed since it achieved its first plasma in 2008. Because it is a superconducting machine and is working toward AT research, it has unique features in terms of the machine engineering and operation. The toroidal field (TF) magnet coils are made of Nb<SUB>3</SUB>Sn, which provide high TFs up to 3.5 T, and have been fully tested. The poloidal field (PF) magnet coils, consisting of both Nb<SUB>3</SUB>Sn and NbTi, which have a maximum current of 25 kA in their design, were tested up to 15 kA. A thermal hydraulic analysis is being conducted for PF magnet coil operation. All plasma-facing components (PFCs) are equipped with water cooled graphite tiles and have the capability of being baked up to 350°C. A startup scenario, which considered both the effect of the ferromagnetic material in the cable in conduit conductor jacket of the magnet coils as well as a nonferromagnetic up-down asymmetry in the cryostat structure, was developed and demonstrated its effectiveness by the last two year's reliable operations. Passive stabilizers and in-vessel control coils (IVCCs) are key components to realize AT operation in KSTAR. The segmented IVCC coils were connected to form circular coils for internal vertical control in 2010, and diverted plasmas with high elongation (κ~1.8, δ>;0.6) were achieved. A neutral beam injection (NBI) system was developed aiming at 2 MW, 300 s per ion source which meets the long-pulse requirement of KSTAR. An NBI ion source with a power of 1.7 MW at 100 kV has been commissioned for 10 s. Finally, ELMy H-modes were successfully produced with 1.3-MW NBI power at a plasma current of 0.6 MA in the 2010 campaign. The first H-mode discharge (#4200) in KSTAR was achieved one year earlier than officially planned and was done at B<SUB>T</SUB> = 2 T with I<SUB>p</SUB> = 0.6 MA in a well-balanced double null configuration after boronization on the PFC. Successful operations in the early days of KSTAR including H-mode experiments revealed the capability of advanced and steady-state operation which is essential for the international thermonuclear experimental reactor (ITER) and future fusion reactors.</P>

Effect of Total Mixed Ration with Fermented Feed on Ruminal In vitro Fermentation, Growth Performance and Blood Characteristics of Hanwoo Steers

Kim, S.H.,Alam, M.J.,Gu, M.J.,Park, K.W.,Jeon, C.O.,Ha, Jong-K.,Cho, K.K.,Lee, S.S. Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.2

In this study, two experiments were conducted to evaluate the total mixed ration with fermented feed (TMRF) and total mixed ration (TMR) by rumen in vitro fermentation and their effects on the growth performance and blood characteristics of Hanwoo steers. In experiment 1, three Hanwoo steers ($600{\pm}47$ kg), each permanently fitted with a ruminal cannula were used. In this experiment, three diets designated as T1, TMRF (18.4% fermented feed, tall fescue, mammoth wild rye forage and whole crop barley); T2, TMRF (17.7% fermented feed, rice straw and whole crop barley); and T3, TMR (rice straw, whole crop barley and probiotics, but no fermented feed), which were subjected to rumen in vitro fermentation for 48 h. The results demonstrated that DM disappearance rate gradually increased with advancing fermentation time, but T1 and T2 were higher than the T3 (p<0.05) from 3 h to 12 h, but insignificant (p>0.05) at 24 and 48 h. None of the specific VFAs were affected except for acetic and non volatile lactic acids, which were produced more in T2 than in T1 and T3 at 24 h and 48 h of incubation. A/P was lower in T1 and T2 than inT3 at 24 h (p<0.05) and 48 h (p>0.05) of incubation. These results confirmed that TMRF-related treatment shows a superior performance to that of TMR during the ruminal fermentation period. In experiment 2, the three diets in experiment 1 plus 1 more control diet (concentrates, probiotics and 2% rice straw of body weight) were fed to the 48 Hanwoo steers ($160{\pm}10$ kg) for a period of 168 d. The results demonstrated that the daily and total live weight gain and feed efficiency were higher (p<0.05) in the TMRF and TMR groups than in the control group. SGOT, SGPT and BUN (p<0.05) were reduced in TMRF relative to the control and TMR groups by 168 d which confirmed that TMRF shows better blood profiles than the TMR and control groups. Overall, these results appear to show that TMRF has better in vitro ruminal characteristics than those of TMR; growth performance and blood profiles were also found to be superior in TMRF than in the TMR and control groups. Thus, our findings suggest that TMRF-based feed supplies are favorable for Hanwoo cattle.

Distinct clinical courses according to presenting phenotypes and their correlations to <i>ATP7B</i> mutations in a large Wilson's disease cohort

Lee, Beom H.,Kim, Joo H.,Lee, Sun Y.,Jin, Hye Y.,Kim, Kwi‐,Joo,Lee, Jin‐,Joo,Park, Jung‐,Young,Kim, Gu‐,Hwan,Choi, Jin‐,Ho,Kim, Kyung M.,Yoo, Han‐,Wook Blackwell Publishing Ltd 2011 Liver International Vol.31 No.6

<P><B>Abstract</B></P><P><B>Introduction and aims: </B> Wide phenotypic and genotypic heterogeneities in Wilson's disease (WD) have been reported, hampering the study of their correlations. The goal of this study was to identify the factors related to these diversities.</P><P><B>Methods: </B> Clinical courses and molecular genetic characteristics were analysed in 237 unrelated Korean WD families. The average follow‐up period was 8.2 ± 5.8 years.</P><P><B>Results: </B> Presenting phenotypes were classified as H1 (12.2%), H2 (42.4%), N1 (21.6%), N2 (0.4%), NX (0.4%), presymptomatic (22.4%) and other (0.4%), modifying the guidelines by Ferenci and colleagues. Age at presentation was youngest and cirrhosis was rarest in the presymptomatic group. Decompensated cirrhosis was the highest in the H1 group. Favourable outcome was rarest in the N1 group. Forty‐seven (11 novel) <I>ATP7B</I> mutations were identified in 85% of the 474 alleles. Multiplex ligation‐dependent probe amplification assays in <I>ATP7B</I> and analyses of <I>ATOX1</I> and <I>COMMD1</I> genes identified no additional mutations. Yeast complementation assays demonstrated functional perturbation of the seven novel missense mutants. Five major mutations, p.Arg778Leu, p.Ala874Val, p.Asn1270Ser, p.Lys838SerfsX35 and p.Leu1083Phe, accounted for 63% of the alleles. H1 was more common, age at presentation was younger and N1+N2+NX tended to be less common in patients with nonsense, frame shifting or splicing mutations than in those with missense mutations alone. Patients with both mutations in the transduction (Td) or the ATP hinge domain showed presymptomatic or hepatic manifestations but no neurological manifestation.</P><P><B>Conclusions: </B> The presenting phenotype strongly affects the clinical outcome of WD, and is related to the <I>ATP7B</I> mutation type and location, providing an evidence for genotype–phenotype correlations in WD.</P>

Chronic Treatment of Kthanol Inhibits Proliferation of Normal Fibroblasts,but Not Oncogenie ras-Transformed Cells

Gu, Young Hwa,Park, Mi Sun,Jhun, Byung H . 한국응용약물학회 1998 Biomolecules & Therapeutics(구 응용약물학회지) Vol.6 No.4

The adverse effects of ethanol on cell proliferation have been described for a variety of tissues and cells. In the present study, we investigated whether chronic ethanol intoxication impairs the cell proliferation and DNA synthesis induced by oncogenic H-ras^(v12)- and v-K-ras^(v12)-transformed cells. Ethanol treatment inhibited the cell proliferation and the DNA synthesis of control parental fibroblasts in a time- and dose- dependent manner. In contrast, ethanol did not suppress the proliferation of either oncogenic H-Ras^(v12)- or v-K-ras^(v12)-transformed fibroblasts. Microinjection of oncogenic H-Ras^(v12) protein induces DNA synthesis and ethanol treatment did not interfere with the DNA synthesis. The antiproliferative toxicity of ethanol was rescued by antioxidants, such as N-acetylcysteine and 4-methlpyrazole. These results indicate that the antiproliferative action site of ethanol toxicity lies upstream or is independent of Ras and ethanol exerts its toxicity through a free radical formation.

Accumulated 2-D neutron flux distribution during KSTAR operation

Kwak, Jong-Gu,Lee, Y.S.,Lee, D.R.,Kim, C.S.,Kim, H.S.,Lee, H.J.,Shinohara, K. Elsevier 2018 Fusion engineering and design Vol.136 No.1

<P><B>Abstract</B></P> <P>Since the successful first H-mode in 2010, duration of H-mode is extended to 1 min and the highest stored plasma energy up to 0.6 MJ is obtained by developing hybrid and internal transport barrier (ITB) mode as well as typical H-mode. Major heating system is the neutral beam (NB) of 100 keV with 5.5 MW and it is planned that the new additional 6 MW NBI is installed in 2018. So there is a lot of production of fast neutrons coming from via D(d,n)<SUP>3</SUP>He reaction and it is found that most of neutrons are 2.45 MeV neutrons coming from deuterium beam plasma interaction and the total neutron fluence during a campaign could be estimated to be about 10<SUP>19</SUP>. In particular, several nickel activation samples are installed inside/outside the vacuum vessel poloidally and toroidally and the total accumulated neutron flux is estimated from 811 keV gamma emission measurement after the campaign. The results show that the neutron activation both inside and outside the vacuum vessel has toroidally non-axisymmetric distribution and it has the highest neutron flux around poloidal limiter area. Considering the prompt ion loss at nominal KSTAR operation including the high beta-p operation, prompt loss ions from 100 keV neutral ion beams hitting on three poloidal limiters was not negligible and the non-uniform distribution is discussed in term of prompt ion loss to the poloidal limiter. In addition, this work reports on the quantitative analysis of poloidal distribution of the neutron emission based on accumulated flux measurements.</P>

초음파를 이용한 H형의 전동 칫솔에 관한 연구

정준섭(J. S. Jeong),김현아(H. A. Kim),김하영(H. Y. Kim),김도원(D. W. Kim),황준원(J. W. Hwang),박범순(B. S. Park),구병관(B. G. Gu),변경석(K. S. Byeon) 한국생산제조학회 2021 한국생산제조시스템학회 학술발표대회 논문집 Vol.2021 No.7

Effect of V Addition on Hardness and Electrical Conductivity in Cu-Ni-Si Alloys

한승전,J. H. Gu,이재현,Z. P. Que,J. H. Shin,임성환,김상식 대한금속·재료학회 2013 METALS AND MATERIALS International Vol.19 No.4

The effect of vanadium (V) addition on the microstructure, the hardness and the electrical conductivity of Cu-2.8Ni-0.7Si alloys was investigated. The V-free, the 0.1 wt% V-added, the 0.2 wt% V-added Cu base alloys were exposed to the same experimental conditions. After the cold rolling of the studied alloys, the matrix was recrystallized during the solution heat treatment at 950 °C for 2 h. However, small amounts of vanadium substantially suppressed the recrystallization and retarded the grain growth of the Cu base alloys. The added vanadium accelerated the precipitation of Ni2Si intermetallic compounds during aging and therefore it contributed positively to the resultant hardness and electrical conductivity. It was found that the hardness and the electrical conductivity increased simultaneously with increasing aging temperature and time with accelerated precipitation kinetics by the addition of vanadium. In the present study, the Cu-2.8Ni-0.7Si alloy with 0.1 wt%V was found to have an excellent combination of the hardness and the electrical conductivity when it was aged at 500 °C.

Catalytic application of metallic iron from the dyeing sludge ash for benzene steam reforming reaction in tar emitted from biomass gasification

Nam, S. B.,Park, Y. S.,Yun, Y. S.,Gu, J. H.,Sung, H. J.,Horio, M. Springer Science + Business Media 2016 Korean Journal of Chemical Engineering Vol.33 No.2

<P>Because it is the most promising method for reforming tar in a gasification system, a catalytic steam reforming reaction of tar using a dyeing sludge ash catalyst that contains mostly iron oxide has been modeled using benzene to investigate whether a steam reforming catalyst produced from waste is viable. The catalytic activity of the ash catalyst is similar to that of the commercially available iron-chrome-based catalyst for the same equivalent total amount of Fe2O3. The activity over the ash catalyst has been examined in terms of the weight hour space velocity (WHSV) and the reaction temperature to develop a model for the reaction kinetics. Using a power law model, the reaction order coefficients of the benzene and steam were estimated to be 0.43 and 0, respectively. The activation energy required for the ash catalyst was approximately 187.6 kJ mol(-1). In addition, the reductive properties of the iron oxide in the ash catalyst were also examined via XRD and H-2-TPR analyses.</P>

Effects of turbulence intensity and exterior geometry on across-wind aerodynamic damping of rectangular super-tall buildings

Y. Quan,H.L. Cao,M. Gu 한국풍공학회 2016 Wind and Structures, An International Journal (WAS Vol.22 No.2

Across-wind aerodynamic damping ratios are identified from the wind-induced acceleration responses of 15 aeroelastic models of rectangular super-high-rise buildings in various simulated wind conditions by using the random decrement technique. The influences of amplitude-dependent structural damping ratio and natural frequency on the estimation of the aerodynamic damping ratio are discussed and the identifying method for aerodynamic damping is improved at first. Based on these works, effects of turbulence intensity Iu, aspect ratio H/B, and side ratio B/D on the across-wind aerodynamic damping ratio are investigated. The results indicate that turbulence intensity and side ratio are the most important factors that affect across-wind aerodynamic damping ratio, whereas aspect ratio indirectly affects the aerodynamic damping ratio by changing the response amplitude. Furthermore, empirical aerodynamic damping functions are proposed to estimate aerodynamic damping ratios at low and high reduced speeds for rectangular super-high-rise buildings with an aspect ratio in the range of 5 to 10, a side ratio of 1/3 to 3, and turbulence intensity varying from 1.7% to 25%.