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Tetramic acid-motif natural products from a marine fungus Tolypocladium cylindrosporum FB06 and their anti-Parkinson activities

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Marine Life Science & Technology 2024年第1期6卷 84-92页

作者： Yuna jung Chaesun Kwon Taeyeon Kim Jin woo Lee Min-Kyoo Shin Sang Hee Shim Natural Products Research Institute College of PharmacySeoul National UniversitySeoul 08826Republic of Korea College of Pharmacy and Research Institute of Pharmaceutical Sciences Seoul National UniversitySeoul 08826Republic of Korea College of Pharmacy Duksung Women’s UniversitySeoul 01369Republic of Korea

Tetramic acid-containing natural products are attracting significantly increasing attention from biologists and chemists due to their intriguing structures and biological *** the present study,two new tetramic acid alkaloids tolypyridone I(1)and tolypyridone J(2),together with five known ones(3–7),were isolated from cultures of a marine fungus Tolypocladium cylindrosporum FB06 isolate obtained from a marine sediment in Beaufort sea of North *** structures were elucidated using 1D,2D NMR,and *** configurations were established on the basis of 1H coupling constants,ROESY correlations and DP4 *** 2 was isolated as mixtures of rotational isomers with C-3 to C-7 axis between 4-hydroxy-2-pyridone and 1-ethyl-3,5-dimethylcyclohexane,hindering *** our unbiased screening to discover neuroprotective compounds in an in vitro Parkinson’s disease(PD)model,SH-SY5Y dopaminergic cells were treated with isolated compounds followed by treatment with 1-methyl-4-phenylpyridinium(MPP^(+)),a parkinsonian *** tested compounds,F-14329(7)significantly protected cells from MPP^(+)-induced ***^(+)-mediated cell death is known to be related to the regulation of Bcl-2 family proteins,specifically the down-regulation of anti-apoptotic Bcl-2 and the up-regulation of pro-apoptotic Bax *** with 2 mmol/L of MPP^(+)for 24 h significantly reduced Bcl-2 levels compared to control treated with ***,treatment with F-14329(7)attenuated such *** study demonstrates that tetramic acid-motif compounds could be potential lead compounds for treating PD.

关键词： Tolypocladium cylindrosporum Tetramic acid Tolypyridone Parkinson’s disease

Shear Behavior in Indented Concrete Layers with Different Strengths

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Engineering（科研） 2016年第7期8卷 423-431页

作者： Jae-Yoon Kang Jong-Sup Park woo-tai jung Moon-Seoung Keum Structural Engineering Research Institute Korea Institute of Civil Engineering and Building Technology Goyang Republic of Korea

This paper investigates the design formula for the shear strength at the concrete-to-concrete interface proposed in Eurocode with regard to concrete layers with different strengths. Based upon the results of the study on the applicability of the design formula, push-off test is conducted on specimens with various indented interfaces to evaluate the actual behavior with respect to the surface roughness. The experimental results reveal that the interfacial shear strength increases with higher compressive strength of the concrete layers presenting different strengths and that the shear strength at the indented interface differs by 20% to 50% compared to the value predicted by the design formula. Especially, the shear strength developed between the concrete layers with different strengths appears to be different from the prediction of the design formula as much as the layers present larger difference in their compressive strengths.

关键词： Shear Strength Interface of Concrete Layers Surface Roughness Indented Surface Push-Off Test

Parametric Analysis on the Optimal Dimensions of Steel Sleeve in Swaging Type Anchorage for CFRP Tendon

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Engineering（科研） 2013年第11期5卷 902-908页

作者： Jae Yoon Kang Jong Sup Park woo tai jung Moon Seoung Kum Structural Engineering Research Division Korea Institute of Construction Technology Goyang Korea

This paper presents the parametric analysis conducted to derive the optimal dimensions of the steel sleeve necessary to secure the bond performance of the swaging type anchorage for CFRP tendon with diameter of 5 mm. To that goal, finite element analysis is performed on the parameters determining the dimensions of the sleeve like the thickness and inner diameters of the sleeve. The results show that a constant swaging pressure of about 450 MPa on the mean is distributed in the sleeve when the thickness ratio of the stress relief zone to the effective swaging zone of the sleeve is larger than 1.1 and that the swaging pressure tends to reduce linearly as much as this thickness ratio becomes smaller than 1.1. The pressure varies within a range of about 30% according to the change in the inner diameter of the sleeve whereas varies within a range less than 10% according to the change in the inner diameter when the thickness ratio is larger than 1.1. Finally, the optimal dimensions of the steel tube sleeve enabling to secure an anchor force larger than the rupture strength of the CFRP tendon with diameter of 5 mm are determined based upon the results of the parametric analysis.

关键词： CFRP Tendon Prestressing Swaging Type Anchorage Swaging Sleeve

Surface-modified Ag@Ru-P25 for photocatalytic CO_(2) conversion with high selectivity over CH_(4) formation at the solid–gas interface

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Carbon Energy 2024年第1期6卷 182-196页

作者： Chaitanya B.Hiragond Sohag Biswas Niket SPowar Junho Lee Eunhee Gong Hwapyong Kim Hong Soo Kim Jin-woo jung Chang-Hee Cho Bryan M.Wong Su-Il In Department of Energy Science&Engineering Daegu Gyeongbuk Institute of Science and Technology(DGIST)DaeguRepublic of Korea Department of Chemical&Environmental Engineering Materials Science&Engineering ProgramDepartment of ChemistryDepartment of Physics&AstronomyUniversity of California-RiversideRiversideCaliforniaUSA Department of Physics and Chemistry Daegu Gyeongbuk Institute of Science and Technology(DGIST)DaeguRepublic of Korea NiceScience Corporation DaeguRepublic of Korea

Systematic optimization of the photocatalyst and investigation of the role of each component is important to maximizing catalytic activity and comprehending the photocatalytic conversion of CO_(2) reduction to solar fuels.A surface-modified Ag@Ru-P25 photocatalyst with H_(2)O_(2) treatment was designed in this study to convert CO_(2) and H_(2)O vapor into highly selective *** doping followed by Ag nanoparticles(NPs)cocatalyst deposition on P25(TiO_(2))enhances visible light absorption and charge separation,whereas H_(2)O_(2) treatment modifies the surface of the photocatalyst with hydroxyl(–OH)groups and promotes CO_(2) ***-resonance transmission electron microscopy,X-ray photoelectron spectroscopy,X-ray absorption near-edge structure,and extended X-ray absorption fine structure techniques were used to analyze the surface and chemical composition of the photocatalyst,while thermogravimetric analysis,CO_(2) adsorption isotherm,and temperature programmed desorption study were performed to examine the significance of H_(2)O_(2) treatment in increasing CO_(2) reduction *** optimized Ag1.0@Ru1.0-P25 photocatalyst performed excellent CO_(2) reduction activity into CO,CH4,and C2H6 with a~95%selectivity of CH4,where the activity was~135 times higher than that of pristine TiO_(2)(P25).For the first time,this work explored the effect of H_(2)O_(2) treatment on the photocatalyst that dramatically increases CO_(2) reduction activity.

关键词： gas-phase CO_(2) reduction H_(2)O_(2) treatment plasmonic nanoparticles solar fuel photocatalyst surface modification

Behavior Characteristics of Bonded Type Anchorage for CFRP Tendon

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Engineering（科研） 2013年第11期5卷 909-918页

作者： Jong Sup Park woo tai jung Jae Yoon Kang Moon Seoung Kum Structural Engineering Research Division Korea Institute of Construction Technology Goyang Korea

This paper examines the shear stress and displacement occurring in CFRP tendons through finite element analysis on the parameters influencing the anchoring performance to evaluate the behavioral characteristics of the bonded type anchorage for CFRP tendon. The selected parameters are the inner angle of the anchorage barrel, the friction between the barrel and filling material, and the elastic modulus of the filling material. The difference in the behavioral characteristics is examined for each parameter. In view of the analytic results, the shear stress developed in the CFRP tendon reduces with larger inner angle of the barrel and lower elastic modulus of the filling material. However, such combination provokes also the increase of the relative displacement of the CFRP tendon. Especially, slip failure may occur due to the lack of the confining force necessary for the anchorage due to the sudden loss of vertical force brought by the wedge force. The experimental results relative to barrel inner angles of 2° and 4° showed that the specimen with an angle of 2° preserved its anchoring performance up to tensile failure whereas the specimen with an angle of 4°?failed in developing its maximum anchoring performance due to slip failure.

关键词： CFRP Tendon Prestressing Anchorage Wedge

Evaluation of the Shear Strength of Perfobond Rib Connectors in Ultra High Performance Concrete

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Engineering（科研） 2014年第13期6卷 989-999页

作者： Jae Yoon Kang Jong Sup Park woo tai jung Moon Seoung Keum Structural Engineering Research Division Korea Institute of Civil Engineering and Building Technology Goyang Korea

Since the previous strength prediction models for the perfobond rib connector were proposed based upon the results of push-out tests conducted on concretes with compressive strength below 50 MPa, push-out test is performed on perfobond shear connectors applying ultra high performance concretes with compressive strength higher than 80 MPa to evaluate their shear resistance. The test variables are chosen to be the diameter and number of dowel holes and, the change in the shear strength of the perfobond rib connector is examined with respect to the strength of two types of UHPC: steel fiber-reinforced concrete with compressive strength of 180 MPa and concrete without steel fiber with compressive strength of 80 MPa. The test results reveal that higher concrete strength and larger number of holes increased the shear strength, and that higher increase rate in the shear strength was achieved by the dowel action. The comparison with the predictions obtained by the previous models shows that the experimental results are close to the values given by the model proposed by Oguejiofor and Hosain [1].

关键词： Perfobond Rib Connector Ultra High Performance Concrete Push-Out Test Shear Strength

Connection between Concrete Layers with Different Strengths

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Engineering（科研） 2015年第7期7卷 365-372页

作者： Jae Yoon Kang Jong Sup Park woo tai jung Moon Seoung Keum Structural Engineering Research Institute Korea Institute of Civil Engineering and Building Technology Goyang Republic of Korea

As part of a research intending to develop steel-concrete hybrid girder using ultra high performance concrete with compressive strength of 80 MPa, this study conducts loading test on this girder to investigate the methods for its composition with a slab using 30 MPa-concrete and the corresponding interfacial behavior. Prior to the loading test, the design formula of the Eurocode for the shear resistance developed in concrete-to-concrete interface is examined for the interface between concrete layers of different strengths. The effect of the surface roughness on the shear resistance is examined using this formula and finite element analysis to verify the applicability of the formula. Based upon the results, loading test is conducted on girder specimens to evaluate the actual behavior with respect to the interfacial surface condition. The test results reveal that the specimen with rough interface could not develop perfectly composite behavior and experienced adhesive failure. In case of simultaneous action of flexure and shear, it appears that conservative design should be applied without consideration of the interfacial condition when determining the arrangement of shear reinforcement.

关键词： Shear Resistance Interface between Concrete Layers Surface Roughness Steel-Concrete Hybrid Girder Ultra High Performance Concrete (UHPC)

Generation of double knockout cattle via CRISPR-Cas9 ribonucleoprotein(RNP)electroporation

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Journal of Animal Science and Biotechnology 2024年第1期15卷 456-462页

作者： Gyeong-Min Gim Kyeong-Hyeon Eom Dong-Hyeok Kwon Dae-Jin jung Dae-Hyun Kim Jun-Koo Yi Jae-jung Ha Ji-Hyun Lee Seong-Beom Lee woo-Jae Son Soo-Young Yum Won-Wu Lee Goo Jang Laboratory of Theriogenology and Biotechnology Department of Veterinary Clinical ScienceCollege of Veterinary Medicine and the Research Institute of Veterinary ScienceSeoul National UniversitySeoulRepublic of Korea LARTBio Co. Ltd.SeoulRepublic of Korea Gyeongsangbukdo Livestock Research Institute YeongjuRepublic of Korea Comparative Medicine Disease Research Center Seoul National UniversitySeoulRepublic of Korea

Background Genome editing has been considered as powerful tool in agricultural ***,genome editing progress in cattle has not been fast as in other mammal species,for some disadvantages including long gestational periods,single pregnancy,and high raising ***,technically demanding methods such as microinjection and somatic cell nuclear transfer(SCNT)are needed for gene editing in *** this point of view,electroporation in embryos has been risen as an *** First,editing efficiency of our electroporation methods were tested for *** of mutation on embryo was confirmed by T7E1 *** first combination,mutation rates for MSTN and PRNP were 57.6%±13.7%and 54.6%±13.5%,*** case of MSTN/BLG,mutation rates were 83.9%±23.6%for MSTN,84.5%±18.0%for ***,the double-KO embryos were transferred to surrogates and mutation rate was identified in resultant calves by targeted deep *** recipients were transferred for MSTN/PRNP,4 calves were delivered,and one calf underwent an induction for double *** surrogates were given double-KO embryos for MSTN/BLG,and four of the six calves that were born had mutations in both *** These data demonstrated that production of genome edited cattle via electroporation of RNP could be effectively ***,MSTN and PRNP from beef cattle and MSTN and BLG from dairy cattle have been born and they will be valuable resources for future precision breeding.

关键词： Beta-lactoglobulin Cattle CRISPR-Cas9 Electroporation Knockout MSTN PRNP

A Miniaturized Crawler Design Based on an Origami-inspired and Geometrically Constrained Spherical Six-bar Linkage

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Journal of Bionic Engineering 2024年第1期21卷 166-176页

作者： Subin Chae Gwang-Pil jung Department of Mechanical and Automotive Engineering Seoul National University of Science and TechnologySeoul 01811South Korea

This paper focuses on a newly developed transmission for a milli-scale eight-legged crawling robot called *** transmission allows intuitive steering by directly changing the direction of the propulsion *** transmission is based on the constrained spherical six-bar *** constrained spherical six-bar linkage passes only reciprocating motion out of the motor’s rotating motion,allowing the crawling legs to kick the ground and obtain *** is achieved by adjusting the geometric constraints of the spherical six-bar using a servomotor,allowing the direction of propulsion to be *** a result,the OriSCO can move along the ground at a speed of 2.15 body lengths/s,and the robot is 60 mm long.

关键词： Bio-inspired robot Crawler:Crawling robot Direction change Spherical six-bar linkage