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Serial evaluation of myocardial function using the myocardial performance index in Kawasaki disease

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World Journal of Pediatrics 2018年第3期14卷 259-268页

作者： Eun song song Somy Yoon Joo Hyun Cho Eun Mi Yang Hwa Jin Cho Young Youn choi Jae Sook Ma Gwang Hyeon Eom Young Kuk Cho Department of Pediatrics Chonnam National University HospitalChonnam National University Medical School42 Jebong-roDong-guGwangju 501-757South Korea Department of Pharmacology and Medical Research Center for Gene Regulation Chonnam National University Medical School160 Baekseo-roDong-guGwangju 61469South Korea Department of Pediatrics KS HospitalGwangjuSouth Korea

Background Kawasaki disease (KD) is known as systemic vasculitis, and more than half of the patients with KD have myo-carditis, which can induce ventricular dysfunction. In this study, we evaluate left ventricular (LV) dysfunction in patients with KD based on the myocardial performance index (MPI) using pulse Doppler (PD) and tissue Doppler imaging (TDI), from the acute to convalescent phases. Methods We retrospectively studied 89 children diagnosed with KD from January 2010 to August 2012. We assessed the presence of coronary artery lesions (CALs) and the LV ejection fraction, PD-MPI, and TDI-MPI at diagnosis, and 2, 14, and 56 days after intravenous immunoglobulin (IVIG) treatment. We enrolled 70 healthy children as a control group. Results The ejection fraction in patients with KD at diagnosis (67.3 ± 0.9%) was lower than that in the control group (69.8 ± 0.8%,P = 0.035), and the LV TDI-MPIs for patients with KD at diagnosis (0.49 ± 0.01) and 2 days after IVIG treatment (0.48 ± 0.01) were higher than those in the control group (0.45 ± 0.01,P = 0.002,P = 0.033, respectively). No signifi cant diff erences were found in the LV dysfunction between the patients with complete and incomplete KD. Septal TDI-MPIs in patients with KD with CAL at diagnosis (0.52 ± 0.02) were higher than those in patients with KD without CAL (0.47 ± 0.01,P = 0.019). Conclusions Transient LV dysfunction occurred in patients with complete and incomplete KD in the acute stage. In patients with KD with CAL at diagnosis, the LV dysfunction was more prominent. The PD-MPI and TDI-MPI are useful parameters for assessing LV function in patients with KD.

关键词： Kawasaki disease Myocardial function Myocardial performance index Tissue Doppler imaging

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皮革的可塑性 POLENE首尔专卖店

室内设计与装修 2025年第1期 90-95页

作者：无 Minwoo(Ian)Yang Sunho Shin Hyevin Park Yongjoon choi(摄影) 秋落(编译) WGNB 不详

继巴黎、纽约和东京之后,专注皮革设计的小众品牌Pol$ne于日前在韩国首尔开设首家品牌旗舰店,也是全球第4间专卖店。这个深受时尚迷和年轻一代欢迎的法国小众品牌,将店址选在逛街胜地之一的江南新沙洞,打造了两层的品牌旗舰店。除了延... 详细信息

继巴黎、纽约和东京之后,专注皮革设计的小众品牌Pol$ne于日前在韩国首尔开设首家品牌旗舰店,也是全球第4间专卖店。这个深受时尚迷和年轻一代欢迎的法国小众品牌,将店址选在逛街胜地之一的江南新沙洞,打造了两层的品牌旗舰店。除了延续品牌形象,引进品牌经典包款和人气新作,受到韩国打卡文化的影响,Pol$ne为首尔旗舰店精心规划出拍照空间,凡是走进店内的人,都会忍不住想要拿起手机留下回忆。

关键词：小众品牌旗舰店皮革品牌形象专卖店 Pol

GNPs/Al nanocomposites with high strength and ductility and electrical conductivity fabricated by accumulative roll-compositing

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Rare Metals 2021年第9期40卷 2593-2601页

作者： Zi-Hao Chen Han-Yu Hui Cheng-Lin Li Feng Chen Xin-Ming Mei Ye Ma Ju-Ying Li Seong-Woo choi Qing-song Mei School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China School of Mechanical Engineering Wuhan Polytechnic UniversityWuhan 430023China Advanced Metals Division Korea Institute of Materials ScienceChangwon 51508Republic of Korea

Aluminum matrix composites(AMCs) reinforced with graphene nanoplatelets(GNPs) were fabricated by using an accumulative roll-compositing(ARC) ***, mechanical and electrical properties of the nanostructured AMCs were characterized. The results showed that small addition(0.2 vol% and 0.5 vol%) of GNPs can lead to a simultaneous increase in the tensile strength and ductility of the GNPs/Al nanocomposites, as compared with the same processed pure Al. With increasing GNPs content, the tensile strength of the GNPs/Al nanocomposites can be enhanced to 387 MPa with retained elongation of 15%. Meanwhile, the GNPs/Al nanocomposites exhibited a good electrical conductivity of77.8%–86.1% that of annealed pure Al. The excellent properties(high strength, high ductility and high conductivity) of the GNPs/Al are associated with the particular ARC process, which facilitates the uniform dispersion of GNPs in the matrix and formation of ultrafine-grained Al matrix. The strengthening and toughening of the GNPs/Al nanocomposites were discussed considering different mechanisms and the unique effect of GNPs.

关键词： Aluminum matrix composites Graphene nanoplatelets Accumulative roll compositing Electrical conductivity Mechanical properties

Synergistic stimulation of surface topography and biphasic electric current promotes muscle regeneration

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Bioactive Materials 2022年第5期7卷 118-129页

作者： Indong Jun Na Li Jaehee Shin Jaeho Park Young Jun Kim Hojeong Jeon Hyuk choi Jae-Gu Cho Byoung Chan choi Hyung-Seop Han Jae-Jun song Environmental Safety Group Korea Institute of Science&Technology Europe(KIST-EUROPE)Saarbrücken66123Germany Department of Otorhinolaryngology-Head and Neck Surgery Korea University College of MedicineSeoul02841Republic of Korea Department of Medical Sciences Graduate School of MedicineKorea UniversitySeoul02841Republic of Korea Center for Biomaterials Biomedical Research InstituteKorea Institute of Science&Technology(KIST)Seoul02792Republic of Korea Laser Surface Texturing Group AYECLUSGyeonggi-do14255Republic of Korea

Developing a universal culture platform that manipulates cell fate is one of the most important tasks in the investigation of the role of the cellular *** study focuses on the application of topographical and electrical field stimuli to human myogenic precursor cell(hMPC)cultures to assess the influences of the adherent direction,proliferation,and differentiation,and induce preconditioning-induced therapeutic ***,a topographical surface of commercially available culture dishes was achieved by femtosecond laser *** detachable biphasic electrical current system was then applied to the hMPCs cultured on laser-textured culture ***-textured topographies were remarkably effective in inducing the assembly of hMPC myotubes by enhancing the orientation of adherent hMPCs compared with flat ***,electrical field stimulation through laser-textured topographies was found to promote the expression of myogenic regulatory factors compared with nonstimulated *** such,we successfully demonstrated that the combined stimulation of topographical and electrical cues could effectively enhance the myogenic maturation of hMPCs in a surface spatial and electrical field-dependent manner,thus providing the basis for therapeutic strategies.

关键词： Topography Electrical field stimulation Femtosecond laser Human myogenic precursor cell Cell therapy

Bimodal grain structures and tensile properties of a biomedical Co-20Cr-15W-10Ni alloy with different pre-strains

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Rare Metals 2021年第1期40卷 20-30页

作者： Cheng-Lin Li Seong-Woo choi Jeong Mok Oh Jae-Keun Hong Jong-Taek Yeom Joo-Hee Kang Qing-song Mei Chan Hee Park Department of Materials Engineering School of Power and Mechanical EngineeringWuhan UniversityWuhan 430072China Advanced Metals Division.Korea Institute of Materials Science Changwon 51508Republic of Korea Materials Testing&Reliability Division Korea Institute of Materials ScienceChangwon 51508Republic of Korea

The influence of pre-strain on the formation of bimodal grain structures and tensile properties of a Co-20 Cr-15 W-10 Ni alloy was *** bimodal grain structures consist of fine grains(FGs;2-3μm in diameter)and coarse grains(CGs;8-16μm in diameter),which can be manipulated by changing the pre-strain(ε=0.3-0.7)and annealing temperatures(1000-1100℃).High pre-strain applied in the samples can intensify the plasticity heterogeneity through increasing the total dislocation density and the local volumes of high-density *** can essentially result in finer FGs,a higher FG volume fraction,and overall grain refinement in the samples after ***-temperature essentially increases both the size and volume fraction of CGs,leading to an increase in the average grain *** tensile test suggests that the bimodal grain structured samples exhibited both high strength and ductility,yield strengths of621-877 MPa and ultimate tensile strengths of1187-1367 MPa with uniform elongations of 55.0%-71.4%.The superior strength-ductility combination of the samples arises from the specific deformation mechanisms of the bimodal grain *** tensile properties strongly depend on the size ratio and volume fraction of FGs/CGs in addition to the average grain size in the bimodal grain *** grain structures can be modified via changing the pre-strain and annealing temperature.

关键词： Biomaterials Bimodal grain structure Deformation heterogeneity Pinning High strength/ductility

Stable operation of highly loaded pure Si-Fe anode under ambient pressure via carboxy silane-directed robust solid electrolyte interphase

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Journal of Energy Chemistry 2024年第7期94卷 568-576页

作者： Guntae Lim Dong Guk Kang Hyeon Gyu Lee Yen Hai Thi Tran Kihun An Junghyun choi Kwang Chul Roh Do Youb Kim Seung-Wan song Department of Chemical Engineering&Applied Chemistry Chungnam National University Daejeon 34134Republic of Korea Energy Storage Materials Center Korea Institute of Ceramic Engineering&TechnologyJinju 52851Republic of Korea Advanced Energy Materials Research Center Korea Research Institute of Chemical TechnologyDaejeon 34114Republic of Korea

Incorporation of higher content Si anode material beyond 5 wt% to Li-ion batteries(LIBs)is challenging,owing to large volume change,swelling,and solid electrolyte interphase(SEI)instability ***,a strategy of diacetoxydimethylsilane(DAMS)additive-directed SEI stabilization is proposed for a stable operation of Si-0.33FeSi_(2)(named as Si-Fe)anode without graphite,which provides siloxane inorganics and organics enrichment that compensate insufficient passivation of fluoroethylene carbonate(FEC)additive and reduce a dependence on *** stable cycling performance of highly loaded(3.5 mA h cm^(-2))pure Si-Fe anode is achieved with 2 wt%DAMS combined with 9 wt%FEC additives under ambient pressure,yielding high capacity 1270 mA h g^(-1)at 0.5 C and significantly improved capacity retention of 81% after 100 cycles,whereas short circuit and rapid capacity fade occur with FEC only ***-directed robust SEI layer dramatically suppresses swelling and particles crossover through separator,and therefore prevents short circuit,demonstrating a possible operation of pure Si or Sidominant anodes in the next-generation high-energy-density and safe LIBs.

关键词： High-energy Li-ion battery Pure Si-Fe anode without graphite Silane additive SEI layer Suppressed swelling

Molecular dynamics study of water diffusion in an amphiphilic block copolymer with large difference in the blocks＇ glass transition temperatures

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Frontiers of Chemical Science and Engineering 2017年第3期11卷 440-447页

作者： Yang Zhou Phillip choi Department of Chemical and Materials Engineering University of Alberta Edmonton Edmonton AB T6G 1H9 Canada

Isothermal-isobaric molecular dynamics simu- lation was used to study the diffusion mechanism of water in polyurethane-block-poly（N-isopropyl acrylamide）（PU- block-PNIPAm） with a hydrophobic PU/hydrophilic PNIPAm mass ratio of 1.4 to 1 at 298 K and 450 K. Here, the experimental glass transition temperature （Tg） of PU is 243 K while that of PNIPAm is 383 K. Different amounts of water up to 15 wt-% were added to PU-block- PNIPAm. We were able to reproduce the specific volumes and glass transition temperatures （250 K and 390 K） of PU- block-PNIPAm. The computed self-diffusion coefficient of water increased exponentially with increasing water concentration at both temperatures （i.e., following the free volume model of Fujita）. It suggested that water diffusion in PU-block-PNIPAm depends only on its fractional free volume despite the free volume inhomo- geneity. It is noted that at 298 K, PU is rubbery while PNIPAm is glassy. Regardless of temperature, radial distribution functions showed that water formed clusters with sizes in the range of 0.2-0.4 nm in PU-block- PNIPAm. At low water concentrations, more clusters were found in the PU domain but at high water concentrations, more in the PNIPAm domain. It is believed that water molecules diffuse as clusters rather than as individual molecules.

关键词： molecular dynamics simulation amphiphilic block copolymer free volume water diffusivity fujita model

Research trend of cascade heat pumps

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Science China(Technological Sciences) 2017年第11期60卷 1597-1615页

作者： BOAHEN Samuel choi JongMin Graduate School of Mechanical Engineering Hanbat National UniversityDaejeon 34158Korea Department of Mechanical Engineering Hanbat National UniversityDaejeon 34158Korea

Most commercial and industrial facilities require very low temperatures for refrigeration and high temperatures for space heating and hot water purposes. Single stage heat pumps have not been able to meet these temperature demands and have been characterized by low capacities and coefficient of performance(COP). Cascade heat pump has been developed to overcome the weaknesses of single stage heat pumps. This study reviews recent works done by researchers on cascade heat pumps for refrigeration, heating and hot water generation. Selection of suitable refrigerants to meet the pressure and temperature demands of each stage of the cascade heat pump has been discussed. Optimization of design parameters such as intermediate temperature(low stage condensing and high stage evaporating temperatures), and temperature difference in the cascade heat exchanger for optimum performance of the cascade heat pump has been reviewed. It was found that optimising each design parameter of the cascade heat pump is necessary for maximum system performance and this may improve the exergetic efficiency, especially of cascade refrigeration systems, by about 30.88%. Cascade heat pumps have wider range of application especially for artificial snow production, in the supermarkets,for natural gas liquefaction, in drying clothes and food and as heat recovery system. The performance of cascade heat pumps can be improved by 19% when coupled with other renewable energy sources for various real time applications. Also, there is the need for much research on refrigerant charge amount of cascade heat pumps, refrigerant-refrigerant heat exchangers to be used as cascade heat exchanger, cascade heat pumps for simultaneous cooling, heating and hot water generation and on the use of variable speed compressors and their control strategies in matching system capacity especially at part load conditions.

关键词： cascade heat pump low stage high stage optimization system performance refrigerant

Cofactor engineering in cyanobacteria to overcome imbalance between NADPH and NADH： A mini review

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Frontiers of Chemical Science and Engineering 2017年第1期11卷 66-71页

作者： Jongmoon Park Yunnam choi Department of Chemical Engineering Pohang University of Science and Technology Gyeongbuk 790-784 Korea School of Environmental Science and Engineering Pohang University of Science and Technology Gyeongbuk 790-784 Korea Division of Advanced Nuclear Engineering Pohang University of Science and Technology Gyeongbuk 790-784 Korea

Cyanobacteria can produce useful renewable fuels and high-value chemicals using sunlight and atmo- spheric carbon dioxide by photosynthesis. Genetic manip- ulation has increased the variety of chemicals that cyanobacteria can produce. However, their uniquely abundant NADPH-pool, in other words insufficient supply of NADH, tends to limit their production yields in case of utilizing NADH-dependent enzyme, which is quite common in heterotrophic microbes. To overcome this cofactor imbalance and enhance cyanobacterial fuel and chemical production, various approaches for cofactor engineering have been employed. In this review, we focus on three approaches：（1） utilization of NADPH- dependent enzymes, （2） increasing NADH production, and （3） changing cofactor specificity of NADH-dependent enzymes from NADH to NADPH.

关键词： NADH-dependent enzyme NADPH-depen-dent enzyme transhydrogenase site-directed mutagenesis,enzyme engineering