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Tetradentate Pt(Ⅱ)complex as a singlet exciton sensitizing host for highly efficient green fluorescent organic light-emitting diodes

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Science China Materials 2024年第8期67卷 2618-2627页

作者： Unhyeok Jo Seung chan Kim chan hee Ryu Kang Mun lee Jae-Min Kim Jun Yeob lee School of Chemical Engineering Sungkyunkwan University2066Seobu-roJangan-guSuwon-siGyeonggi-do 16419Republic of Korea Department of Chemistry Institute for Molecular Science and Fusion TechnologyKangwon National UniversityChuncheonGangwon 24341Republic of Korea Department of Advanced Materials Engineering Chung-Ang University4726Seodong-daeroDaedeok-myeonAnseong-siGyeonggi-do 17546Republic of Korea SKKU Advanced Institute of Nano Technology Sungkyunkwan University2066Seobu-roJangan-guSuwonGyeonggi 16419Republic of Korea SKKU Institute of Energy Science and Technology Sungkyunkwan University2066Seobu-roJangan-guSuwonGyeonggi 16419Republic of Korea

Efficient green fluorescent organic light-emitting diodes were designed with a phosphorescent metal complex as a singlet exciton sensitizing host(SESH)for achieving high efficiency and low efficiency roll-off through exciton and polaron *** Pt(Ⅱ)complex(Pt-Trz)possessing a tetradentate ligand with a bulky blocking group not only suppresses the severe formation of excimer or dimer itself but also transfers radiative excitons to fluorescent dopant *** SESH assisted fluorescence(SESHF)device with Pt-Trz as the host exhibits the maximum external quantum efficiency of 13.3%and a lower efficiency roll-off compared with exciplex host device which is a general approach for harvesting triplet *** exciton dynamics modeling unravels that the SESHF device effectively utilizes triplet excitons in the host by intersystem crossing and resonance energy transfer from the triplet state of the host to the singlet state of the terminal *** quenching rates of the SESHF device are reduced by 11 times for triplet-triplet annihilation and 1.8 times for tripletpolaron annihilation compared with the exciplex device,which demonstrates that Pt-Trz could be a platform to be used as an efficient host for fluorophores.

关键词： singlet annihilation polaron

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Research on Cavitation Characteristics and Influencing Factors of Herringbone Gear Pump

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2917-2946页

作者： Jinlong Yang Kwang-hee lee Chul-hee lee Department of Mechanical Engineering of Inha University Incheon22212South Korea

Cavitation is a common issue in pumps,causing a decrease in pump head,a fall in volumetric efficiency,and an intensification of outlet flow *** is one of the main hazards that affect the regular operation of the *** on pump cavitation mainly focuses on mixed flow pumps,jet pumps,external spur gear pumps,***,there are few cavitation studies on external herringbone gear *** addition,pumps with different working principles significantly differ in the flow and complexity of the internal flow ***,it is urgent to study the cavitation characteristics of external herringbone gear *** with experimentalmethods,visual research and cavitation area identification are achieved through computation fluid dynamic(CFD),and changing the boundary conditions and shape of the gear rotor is *** simulation yields a head error of only 0.003%under different grid numbers,and the deviation between experimental and simulation results is less than 5%.The study revealed that cavitation causes flow pulsation at the outlet,and the cavitation serious area is mainly distributed in the meshing gap and meshing *** can be inhibited by reducing the speed,increasing the inlet pressure,and changing the helix angle can be *** example,when the inlet pressure is 5 bar,the maximumgas volume fraction in themeshing area is less than 50%.These results provide a reference for optimizing the design and finding the optimal design parameters to reduce or eliminate cavitation.

关键词： Herringbone gear pump cavitation rotating speed inlet pressure helix angle TwinMesh

Tetradentate Pt(II) complex as a singlet exciton sensitizing host for highly efficient green fluorescent organic light-emitting diodes

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Science China Materials 2024年

作者： Unhyeok Jo Seung chan Kim chan hee Ryu Kang Mun lee Jae-Min Kim Jun Yeob lee School of Chemical Engineering Sungkyunkwan University 2066 Seobu-ro Jangan-gu Suwon-si Department of Chemistry Institute for Molecular Science and Fusion Technology Kangwon National University Chuncheon Department of Advanced Materials Engineering Chung-Ang University 4726 Seodong-daero Daedeok-myeon Anseong-si SKKU Advanced Institute of Nano Technology Sungkyunkwan University 2066 Seobu-ro Jangan-gu SKKU Institute of Energy Science and Technology Sungkyunkwan University 2066 Seobu-ro Jangan-gu

Efficient green fluorescent organic light-emitting diodes were designed with a phosphorescent metal complex as a singlet exciton sensitizing host (SESH) for achieving high efficiency and low efficiency roll-off through exciton and polaron management. Tetradentate Pt(II) complex (Pt-Trz)possessing a tetradentate ligand with a bulky blocking group not only suppresses the severe formation of excimer or dimer itself but also transfers radiative excitons to fluorescent dopant effectively. The SESH assisted fluorescence (SESHF) device with Pt-Trz as the host exhibits the maximum external quantum efficiency of 13.3%and a lower efficiency roll-off compared with exciplex host device which is a general approach for harvesting triplet excitons. Numerical exciton dynamics modeling unravels that the SESHF device effectively utilizes triplet excitons in the host by intersystem crossing and resonance energy transfer from the triplet state of the host to the singlet state of the terminal emitter. Bimolecular quenching rates of the SESHF device are reduced by 11 times for triplet-triplet annihilation and 1.8 times for tripletpolaron annihilation compared with the exciplex device, which demonstrates that Pt-Trz could be a platform to be used as an efficient host for fluorophores.

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Impact of statin usage patterns on outcomes after percutaneous coronary in-tervention in acute myocardial infarction：Korea Working Group on Myocar-dial Infarction registry （KorMI） study

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Journal of Geriatric Cardiology 2014年第2期11卷 93-99页

作者： chan-hee lee Sang-hee lee Jong-Seon Park Young-Jo Kim Kee-Sik Kim Shung-Chull Chae Hyo-Soo Kim Dong-Ju Choi Myeong-chan Cho Seung-Woon Rha Myung-Ho Jeong Department of Cardiology Yeungnam University Hospital 170 Hyeonchung-ro Nam-gu Daegu 705-717 South Korea Department of Internal Medicine Daegu Catholic University Hospital 33 Duryugongwon-ro 17-gil Nam-gu Daegu 705-718 South Korea Department of Internal Medicine Kyungpook National University Hospital 130 Dongdeok-ro Jung-gu Daegu 700-721 South Korea Department of Internal Medicine Seoul National University Hospital 101 Daehak-ro Jongno-gu Seoul 110-744 South Korea Department of Internal Medicine Seoul National University Bundang Hospital 82 Gumi-ro 173-gil Bundang-gu Seongnam 463-707 South Korea Department of Internal Medicine Chungbuk National University Hospital 776 1sunhwan-ro Heungdeok-gu Cheongju 361-711 South Korea Department of Internal Medicine Korea University Guro Hospital 148 Gurodong-ro Guro-gu Seoul 152-703 South Korea Department of Internal Medicine Chonnam National University Hospital 42 Jebong-ro Dong-gu Gwangju 501-757 South Korea

在心肌的梗塞(STEMI ) 是的尖锐圣片断举起以后的 statin 使用的 BackgroundThe 利益然而，很好证实预定 statin 管理的影响没被阐明。这研究的目的在经皮的冠的干预(一种总线标准) 以后集中了于早临床的结果学习包括了的心肌的梗塞登记... 详细信息

在心肌的梗塞(STEMI ) 是的尖锐圣片断举起以后的 statin 使用的 BackgroundThe 利益然而，很好证实预定 statin 管理的影响没被阐明。这研究的目的在经皮的冠的干预(一种总线标准) 以后集中了于早临床的结果学习包括了的心肌的梗塞登记(KorMI ) 上的朝鲜工作组的 .MethodsThis 分析 3,584 个 STEMI 病人(吝啬的年龄， 63 ±；13 年；男性， 2,684， 74.9%) 从 2008 年 1 月经历一种总线标准到 2009 年 6 月。主要不利心脏的事件的率(向：所有原因死亡，周期性的 MI，和目标损害 revascularization ) 在根据 statin 治疗预定组织的病人之中被比较：我，在期间并且在住院以后(n = 2,653， 74%) ；II，仅仅在住院期间(n = 309， 8.6%) ；III，仅仅在分泌物以后(n = 157， 4.4%) ；并且 IV，没有 statin 治疗(n = 465， 13%) 。吝啬的后续持续时间是 234 ±；statin 的 113 个 *** 因素在住院期间使用包括的优先的 statin 使用，多重 diseased 容器，在心肌的梗塞流动等级 III 的最后的 thrombolysis，和低密度的脂蛋白胆固醇水平。在 6 月的后续，组 III 和 IV 有最高的向率(2.3% ， 3.9% ， 5.1% ，和 4.9% 为组 I-IV，分别地 P = 0.004 ) 。在为 confounders 调整以后，组 II-IV 比组有更高的向风险我[危险比率(HR ) ：3.20， 95% 信心间隔(95%CI ) ：1.31-7.86， P = 0.011；HR：3.84， 95%CI：1.47-10.02， P = 0.006；并且 HR：3.17， 95%CI：1.59-6.40， P = 0.001；分别地] 基于国家注册表数据库， .ConclusionsThis 学习早显示出早、连续的 statin 治疗 improvs 在在真实世界的临床的实践的一种总线标准以后的 STEMI 病人的结果。

关键词：急性心肌梗死他汀类药物冠状动脉注册表韩国拨号 MACE 低密度脂蛋白

Health risks of pest control and disinfection workers after the COVID-19 outbreak in South Korea

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Journal of Environmental Sciences 2024年第5期139卷 350-363页

作者： Yun-hee Choi Da-An Huh Lita Kim Sang ji lee Kyong Whan Moon Department of Health and Safety Convergence Science Korea UniversityAnam-ro 145Seongbuk-guSeoul 02841South Korea BK21 FOUR R&E Center for Learning Health System Korea UniversityAnam-ro 145Seongbuk-guSeoul 02841South Korea Institute of Sciences Korea UniversityAnam-ro 145Seongbuk-guSeoul 02841South Korea Department of Health and Environmental Science Korea UniversityAnam-ro 145Seongbuk-guSeoul 02841South Korea

The exposure patterns of pest control and disinfection workers have changed after the coronavirus disease 2019(COVID-19)outbreak,but the health risks of chemical exposure have not been *** identified these workers’chemical exposure patterns and risks before and after the COVID-19 *** used data conducted between 2018(pre-pandemic)and 2021(post-pandemic)from three-year cross-sectional surveys on pest control and disinfection *** and dermal exposure concentrations were estimated using equations based on a biocidal product risk assessment model from the Korean National Institute of Environmental *** non-carcinogenic and carcinogenic risks of chemicals were calculated using the United States Environmental Protection Agency risk assessment *** found that the annual work frequency(50^(th)percentile)of foggers using disinfectants increased the most among all the work types,from 140 uses/year to 176 uses/year after the COVID-19 ***,all chemicals’non-carcinogenic and carcinogenic risks increased regardless of exposure *** the worst scenario(95^(th)percentile),the margin of exposure for citric acid,benzethonium chloride,benzyl-C12-16-alkyldimethyl chlorides,and sodium chlorite of inhalation exposure,and isopropyl alcohol and benzyl-C12-16-alkyldimethyl chlorides of dermal exposure were acceptable(>100)before the COVID-19outbreak but became unacceptable(10^(-6))before and after the COVID-19 outbreak but comparatively high after the COVID-19 ***,significantly more workers experienced health symptoms after the COVID-19outbreak(p<0.05),with the most common being muscle lethargy(31%),skin/face stinging(28.7%),and breath shortness/neck pain(24.1%).

关键词： Biocide Disinfection Health risk assessment Occupational exposure Pest control

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Two-stage dynamic recrystallization and texture evolution in Al-7Mg alloy during hot torsion

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International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1900-1911页

作者： Kwang Tae Son chang hee Cho Myoung Gyun Kim Ji Woon lee School of Mechanical Industrialand Manufacturing EngineeringOregon State UniversityCorvallis OR 97331USA Department of Materials Science Engineering Northwestern UniversityEvanston IL 60208USA Research Institute of Industrial Science and Technology(RIST) Pohang 37673Rep.of Korea Division of Advanced Materials Engineering Kongju National UniversityCheonan 31080Rep.of Korea Center for Advanced Materials and Parts of Powders Kongju National UniversityCheonan 31080Rep.of Korea

Hot torsion tests were performed on the Al-7Mg alloy at the temperature ranging from 300 to 500℃ and strain rates between 0.05 and 5 s^(-1) to explore the progressive dynamic recrystallization(DRX)and texture *** DRX behavior of the alloy manifested two distinct stages:Stage 1 at strain of≤2 and Stage 2 at strains of≥*** Stage 1,there was a slight increase in the DRXed grain fraction(X_(DRX))with predominance of discontinuous DRX(DDRX),followed by a modest change in X_(DRX) until the transition to Stage *** 2 was marked by an accelerated rate of DRX,culminating in a substantial final X_(DRX) of~*** backscattered diffraction(EBSD)analysis on a sample in Stage 2 revealed that continuous DRX(CDRX)predominantly occurred within the(121)[001]grains,whereas the(111)[110]grains underwent a geometric DRX(GDRX)evolution without a noticeable sub-grain ***,a modified Avrami’s DRX kinetics model was utilized to predict the microstructural refinement in the Al-7Mg alloy during the DRX *** this kinetics model did not accurately capture the DDRX behavior in Stage 1,it effectively simulated the DRX rate in Stage *** texture index was employed to assess the evolution of the texture isotropy during hot-torsion test,demonstrating significant improvement(>75%)in texture randomness before the commencement of Stage *** initial texture evolution is attributed to the rotation of parent grains and the substructure evolution,rather than to an increase in X_(DRX).

关键词： Al-7Mg alloys hot deformation hot torsion tests dynamic recrystazlliation microstructure texture

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Ionizing terahertz waves with 260 MV/cm from scalable optical rectification

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Light(Science & Applications) 2024年第6期13卷 1075-1087页

作者： Hyeongmun Kim Chul Kang Dogeun Jang Yulan Roh Sang Hwa lee Joong Wook lee Jae hee Sung Seong Ku lee Ki-Yong Kim Advanced Photonics Research Institute GISTGwangju61005Korea Department of Physics and Optoelectronics Convergence Research Center Chonnam National UniversityGwangju61186Korea Pohang Accelerator Laboratory POSTECHPohang37673Korea Center for Relativistic Laser Science Institute for Basic ScienceGwangju61005Korea Institute for Research in Electronics and Applied Physics Department of PhysicsUniversity of MarylandCollege ParkMaryland20742USA

Terahertz(THz)waves,known as non-ionizing radiation owing to their low photon energies,can actually ionize atoms and molecules when a sufficiently large number of THz photons are concentrated in time and ***,we demonstrate the generation of ionizing,multicycle,15-THz waves emitted from large-area lithium niobate crystals via phase-matched optical rectification of 150-terawatt laser pulses.A complete characterization of the generated THz waves in energy,pulse duration,and focal spot size shows that the field strength can reach up to 260 megavolts per *** particular,a single-shot THz interferometer is employed to measure the THz pulse duration and spectrum with complementary numerical *** intense THz pulses are irradiated onto various solid targets to demonstrate THz-induced tunneling ionization and plasma *** study also discusses the potential of nonperturbative THz-driven ionization in gases,which will open up new opportunities,including nonlinear and relativistic THz physics in plasma.

关键词： optical interferometer matched

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Oncology Research 2024年第2期32卷 421-432页

作者： SEUNG-hee GWAK JUHYUN lee EUNJI OH DOHYUN lee WONSHIK HAN JONGMIN KIM KYONG-TAI KIM Department of Life Sciences Pohang University of Science and TechnologyPohang37673Korea R&D Center NovMetaPharma Co.Ltd.Pohang37668Korea Department of Surgery and Cancer Research Institute Seoul National University College of MedicineSeoul03080Korea Generative Genomics Research Center Global Green Research&Development CenterHandong Global UniversityPohang37554Korea

Genetic information is transcribed from genomic DNA to mRNA,which is then translated into threedimensional *** can undergo various post-transcriptional modifications,including RNA editing that alters mRNA sequences,ultimately affecting protein *** this study,RNA editing was identified at the 499th base(c.499)of human vaccinia-related kinase 2(VRK2).This RNA editing changes the amino acid in the catalytic domain of VRK2 from isoleucine(with adenine base)to valine(with guanine base).Isoleucine-containing VRK2 has higher kinase activity than the valine-containing VRK2,which leads to an increase in tumor cell *** we reported that VRK2 directly interacts with dystrobrevin-binding protein(dysbindin)and results in reducing its ***,we demonstrate that isoleucine-containing VRK2 decreases the level of dysbindin than valinecontaining *** interacts with cyclin D and thereby regulates its expression and *** reduction in the level of dysbindin by isoleucine-containing VRK2 further enhances the cyclin D expression,resulting in increased tumor growth and reduction in survival *** has also been observed that in patient samples,VRK2 level was elevated in breast cancer tissue compared to normal breast ***,the isoleucine form of VRK2 exhibited a greater increase in breast cancer ***,it is concluded that VRK2,especially dependent on the 167th variant amino acid,can be one of the indexes of tumor progression and proliferation.

关键词： VRK2 Kinase activity Breast cancer Tumor RNA editing Cell proliferation Cell growth

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