Mitral Loop Cerclage Annuloplasty for Secondary Mitral Regurgitation

Park, Y.H.,Chon, M.K.,Lederman, R.J.,Sung, S.C.,Je, H.G.,Choo, K.S.,Lee, S.H.,Shin, E.S.,Kim, J.S.,Hwang, K.W.,Lee, S.Y.,Chun, K.J.,Kim, C.M.,Kim, J.H. Elsevier 2017 JACC. Cardiovascular interventions Vol.10 No.6

<P>OBJECTIVES This is an early feasibility clinical test of mitral loop cerclage annuloplasty to treat secondary mitral valve regurgitation. BACKGROUND Secondary mitral regurgitation is characterized by cardiomyopathy, mitral annular enlargement, and leaflet traction contributing to malcoaptation. Transcatheter mitral loop cerclage applies circumferential compression to the mitral annulus by creating a loop through the coronary sinus across the interventricular septum, protecting entrapped coronary arteries from compression, and interactive annular reduction under echocardiographic guidance. This is the first human test of mitral loop annuloplasty. METHODS Five subjects with severe symptomatic secondary mitral regurgitation underwent mitral loop cerclage, with echocardiographic and computed tomography follow-up over 6 months. RESULTS Mitral loop cerclage was successful in 4 of 5 subjects and aborted in 1 of the 5 because of unsuitable septal coronary vein anatomy. Immediately and over 6 months, measures of both mitral valve regurgitation (effective orifice area and regurgitation fraction) and chamber dimensions (left atrial and left ventricular volumes) were reduced progressively and ejection fractions increased. Two with persistent and permanent atrial fibrillation spontaneously reverted to sinus rhythm during follow-up. One subject experienced a small myocardial infarction from an unrecognized small branch coronary occlusion. Another, experiencing cardiogenic shock at baseline, died of intractable heart failure after 6 weeks. CONCLUSIONS In this first human test, mitral loop cerclage annuloplasty was successful in 4 of 5 attempts, caused reverse remodeling (reduction in secondary mitral regurgitation and heart chamber volumes), and suggested electrical remodeling (reversion of atrial fibrillation). Further evaluation is warranted. (C) 2017 by the American College of Cardiology Foundation. Published by Elsevier. All rights reserved.</P>

Orbital hybridization mechanism for the enhanced photoluminescence in edge-functionalized sp² carbon clusters

Kang, B.,Choi, Y.,Kim, B.S.,Youn, I.S.,Lee, G. Pergamon Press ; Elsevier Science Ltd 2016 Carbon Vol.109 No.-

<P>Using the first principles methods, we performed systematic study on the effect of edge-functional groups on the electronic energy levels and the optical properties of sp(2) carbon clusters. It is found that the intrinsic pi and pi* orbitals are weakly altered by oxygen-bearing functional groups, but it is significantly disrupted by pyrrolic groups. Thereby the oscillator strength of the lowest-energy transition is found to be much stronger for the pyrrolic group functionalized cluster than for the carboxyl group. From our results being consistent with the experimental reports, we suggest that the photoluminescence enhancement is caused by a perturbation of the intrinsic, frontier molecular orbitals by edge groups. (C) 2016 Elsevier. Ltd. All rights reserved.</P>

Role of Leu188 in the Fatty Acid Hydroxylase Activity of CYP102A1 from Bacillus megaterium

Jang, H.H.,Shin, S.M.,Ma, S.H.,Lee, G.Y.,Joung, Y.H.,Yun, C.H. Elsevier 2016 Journal of molecular catalysis Enzymatic Vol.133 No.-

<P>P450 BM3 (CYP102A1) from Bacillus megaterium catalyzes the subterminal hydroxylation of fatty acids with 12-22 carbons at the omega-1, omega-2 and omega-3 positions. Several amino acids located at the substrate channel and active sites are known to be important for the catalytic activity of CYP102A1. The L188 residue at the C-terminus of alpha-helix F undergoes a large shift upon substrate binding and has frequently been found in different combinations of multiple mutations showing enhanced and altered activities. In this study, we examined the role of the L188 residue by comparing the catalytic activities of wild-type CYP102A1 and 19 mutants of L188. The mutants were made with site-directed mutagenesis and functionally expressed in Escherichia coll. The enzymatic properties of the mutants for a set of fatty acids (C-10-C-16) were compared to the properties of the wild-type. L188Q and L188 P mutants showed especially strong increases in hydroxylase activity toward C-10-C-13 fatty acids, although they did not have activity changes for C-14-C-16 fatty acids. Although most mutants showed very similar overall hydroxylation rates for myristic acid, 14 mutants showed apparent changes in the regioselectivity of hydroxylation with a preference for the omega-3 position over the omega-1 position. A possible role for the L188 residue has been discussed in the context of the structure and function of CYP102A1. (C) 2016 Elsevier B.V. All rights reserved.</P>

Determination of plutonium isotopes (^238,239,240Pu) and strontium (⁹⁰Sr) in seafood using alpha spectrometry and liquid scintillation spectrometry

Shin, C.,Choi, H.,Kwon, H.M.,Jo, H.J.,Kim, H.J.,Yoon, H.J.,Kim, D.S.,Kang, G.J. Elsevier Applied Science Publishers 2017 JOURNAL OF ENVIRONMENTAL RADIOACTIVITY Vol.177 No.-

<P>The present study was carried out to survey the levels of plutonium isotopes (Pu-238,Pu-239,Pu-240) and strontium (Sr-90) in domestic seafood in Korea. In current, regulatory authorities have analyzed radionuclides, such as Cs-134, Cs-137 and I-131, in domestic and imported food. However, people are concerned about contamination of other radionuclides, such as plutonium and strontium, in food. Furthermore, people who live in Korea have much concern about safety of seafood. Accordingly, in this study, we have investigated the activity concentrations of plutonium and strontium in seafood. For the analysis of plutonium isotopes and strontium, a rapid and reliable method developed from previous study was used. Applicability of the test method was verified by examining recovery, minimum detectable activity (MDA), analytical time, etc. Total 40 seafood samples were analyzed in 2014-2015. As a result, plutonium isotopes (Pu-238,Pu-239,Pu-240) and strontium (90Sr) were not detected or below detection limits in seafood. The detection limits of plutonium isotopes and strontium-90 were 0.01 and 1 Bq/kg, respectively. (C) 2017 Elsevier Ltd. All rights reserved.</P>

An intelligent hybrid trading system for discovering trading rules for the futures market using rough sets and genetic algorithms

Kim, Youngmin,Ahn, Wonbin,Oh, Kyong Joo,Enke, David Elsevier 2017 Applied soft computing Vol.55 No.-

<P>Discovering intelligent technical trading rules from nonlinear and complex stock market data, and then developing decision support trading systems, is an important challenge. The objective of this study is to develop an intelligent hybrid trading system for discovering technical trading rules using rough set analysis and a genetic algorithm (GA). In order to obtain better trading decisions, a novel rule discovery mechanism using a GA approach is proposed for solving optimization problems (i.e., data discretization and reducts) of rough set analysis when discovering technical trading rules for the futures market. Experiments are designed to test the proposed model against comparable approaches (i.e., random, correlation, and GA approaches). In addition, these comprehensive experiments cover most of the current trading system topics, including the use of a sliding window method (with or without validation dataset), the number of trading rules, and the size of training period. To evaluate an intelligent hybrid trading system, experiments were carried out on the historical data of the Korea Composite Stock Price Index 200 (KOSPI 200) futures market. In particular, trading performance is analyzed according to the number of sets of decision rules and the size of the training period for discovering trading rules for the testing period. The results show that the proposed model significantly outperforms the benchmark model in terms of the average return and as a risk-adjusted measure. (C) 2017 Elsevier B.V. All rights reserved.</P>

Catalytic activity of Pt/SiO2 nanocatalysts synthesized via ultrasonic spray pyrolysis process under CO oxidation

Jung, Chan-Ho,Yun, Jaecheol,Qadir, Kamran,Naik, Brundabana,Yun, Jung-Yeul,Park, Jeong Young Elsevier 2014 Applied Catalysis B Vol.154 No.-

We report the catalytic activity of Pt/SiO2 nanocatalysts synthesized via the ultrasonic spray pyrolysis (USP) process under CO oxidation. We found that the average particle size of the dispersed platinum nanoparticles can be controlled by changing the concentration of the Pt precursor and the calcination conditions. The amount of loaded platinum on the SiO2 powder increased as the precursor concentration increased, while the specific surface area of the Pt/SiO2 samples decreased. As the calcination temperature and time increased, the size of the platinum particles on the SiO2 increased. As for catalytic reactivity, high loading of Pt/SiO2 showed a higher conversion of CO. The turnover rate of the Pt/SiO2 catalysts increased after calcination at 600 degrees C, then decreased after calcination at 750 degrees C, mainly due to agglomeration at the high temperature and partly because of severe oxidation. The catalytic activity of the Pt/SiO2 nanocatalysts synthesized using LISP exhibited higher catalytic activity compared with Pt/SiO2 synthesized via wet chemical synthesis or wetness impregnation. It is attributed to better dispersion of the nanoparticles on the SiO2 as well as the removal of hydrocarbon impurities during calcination. This work demonstrated the successful use of the spray pyrolysis process for synthesis of oxide-supported metal catalysts with high thermal stability and activity. (C) 2014 Elsevier B.V. All rights reserved.

Improved production of 2'-fucosyllactose in engineered Escherichia coli by expressing putative α-1,2-fucosyltransferase, WcfB from Bacteroides fragilis

Chin, Y.W.,Kim, J.Y.,Kim, J.H.,Jung, S.M.,Seo, J.H. Elsevier Science Publishers 2017 Journal of biotechnology Vol.257 No.-

<P>2 '-Fucosyllactose (2-FL) is one of most abundant oligosaccharides in human milk, which is involved in many biological functions for infant health. Since 2-FL has a great potential in application to functional food materials and pharmaceuticals, several microbial systems for mass production of 2-FL have been developed in recent years. Microbial production of 2-FL was suggested to be influenced by a number of factors including fucosylation activity of alpha-1,2-fucosyltransferase. In the present study, the wcfB gene coding for alpha-1,2-fucosyltransferase from Bacteroides fragilis was screened from eleven candidates of putative alpha-1,2-fucosyltransferase. Introduction of the wcfB gene allows the lacZ-deleted strain of E. coli expressing the genes for guanosine 5'-diphosphate (GDP)-l-fucose biosynthetic enzymes to produce 2-FL. As a result of fed-batch fermentation, 15.4g/L extracellular concentration of 2-FL with 2-FL yield of 0.858g/g lactose and productivity of 0.530g/L/h were obtained. In addition, the feasibility of industrial production of 2-FL using this microbial system was demonstrated by performing fed-batch fermentation in a 75L bioreactor. (C) 2016 Elsevier B.V. All rights reserved.</P>

Fabrication of flexible optoelectronic devices based on MoS₂/graphene hybrid patterns by a soft lithographic patterning method

Kang, Min-A.,Kim, Seong Jun,Song, Wooseok,Chang, Sung-jin,Park, Chong-Yun,Myung, Sung,Lim, Jongsun,Lee, Sun Sook,An, Ki-Seok Elsevier 2017 Carbon Vol.116 No.-

<P>A cross-stacking MoS2/graphene hybrid patterns for the application to advanced flexible opto-electronic devices have been demonstrated by soft-lithographic patterning method. Well-defined MoS2/graphene hybrid pattern was fabricated simply by a soft lithographic patterning technique. In-depth exploration for the optical properties of diverse cross-stacking photodetectors based on MoS2/graphene patterns was carried out. In addition, cross-stacking MoS2/graphene was demonstrated onto a flexible polyethylene terephthalate (PET) substrate for the analysis of physical properties of devices. Substantially, this method should pave the way for realistic applications of transparent and flexible nano-electronic devices based on 2D materials. (C) 2017 Elsevier Ltd. All rights reserved.</P>

Synthesis and luminescent features of NaCaPO₄:Tb³⁺ green phosphor for near UV-based LEDs

Ratnam, B.V.,Jayasimhadri, M.,Bhaskar Kumar, G.,Jang, K.,Kim, S.S.,Lee, Y.I.,Lim, J.M.,Shin, D.S.,Song, T.K. Elsevier Sequoia 2013 JOURNAL OF ALLOYS AND COMPOUNDS Vol.564 No.-

<P>An efficient green emitting Tb3+ doped NaCaPO4 (NCP) phosphor was synthesized by using conventional solid-state reaction for solid-state lighting applications. X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), FT-IR, emission and excitation properties were extensively investigated for NCP phosphors. X-ray diffraction analysis confirmed the formation of NaCaPO4 with orthorhombic structure. The excitation spectrum consists of strong 4f-4f transition at around 370 nm, which has higher intensity than the f-d transition. Emission spectra indicated that this phosphor can be efficiently excited by UV light in the range from 250 to 400 nm, and shows strong emission band centered at 547 nm. Analysis of the emission spectra with different Tb3+ concentrations revealed that the optimum dopant concentration for these NCP phosphors is about 5 mol% of Tb3+. Diminishing of D-5(3) level and increasing of D-5(4) level emission intensity with the Tb3+ concentration explained successfully. The emission color was analyzed and confirmed with the help of chromaticity coordinates and color temperature. The excellent luminescent properties of NaCaPO4: Tb3+ phosphor makes it as a potential green phosphor upon near-UV LED excitation. (C) 2013 Elsevier B.V. All rights reserved.</P>

Controversy detection in Wikipedia using semantic dissimilarity

Jhandir, M. Zeeshan,Tenvir, Ali,On, Byung-Won,Lee, Ingyu,Choi, Gyu Sang Elsevier science 2017 Information sciences Vol.418 No.-

<P>The advent of search engines and wikis has made access to information easy and almost free. Wikipedia is the efficacious outcome of an enormous collaboration, and its peer review-like methods of creation, maintenance, and evolution of contents, ensure high quality and reliability. However, the 'anyone-can-edit' policy of Wikipedia has created many problems such as trolling, vandalism, controversies, and doubts about the content and reliability of the information provided due to non-expert involvement. People have tried to identify and rank controversies in Wikipedia articles through various techniques that use quantitative data, ignoring the semantic significance of conflicts among authors. In this paper, we have addressed the problem of identifying controversy using natural language processing techniques for the first time. The proposed method spots the impact on existing meanings of the text due to new editing processes along with their relationship to the topic of the article. The experimental results for precision (0.901), recall (0.901), accuracy (0.908), and F-measure (0.901) demonstrate the effectiveness of the proposed method. The technique is deemed useful for automatic identification of conflicts newly introduced into existing article contents, and could prove helpful in making decisions for inclusion or exclusion of controversies under the same topic. (C) 2017 Elsevier Inc. All rights reserved.</P>