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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

阵发性和持续性心房颤动病人左房纤维化的MRI评估

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国际医学放射学杂志 2019年第6期 726-726页

作者： D.K.Lee j.shim j.Choi Y.H.Kim Y.W.Oh S.H.Hwang 蒋梦迪 Department of Radiology Korea University Anam Hospital

摘要电生理学研究表明,左心房钆对比剂延迟强化(LGE)与心房颤动(房颤,AF)的持续时间有关。目前,虽然心脏MRI已应用于评估心房LGE的程度,但是LGE在左心房

关键词：持续性心房颤动阵发性房颤持续性房颤纤维化 MRI

房颤:左心房压力与速度编码心脏MR成像上左心耳排空的关系

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国际医学放射学杂志 2017年第5期 595-595页

作者： S.H.Hwang S.Y.Roh j.shim j.Choi Y.Kim Y.Oh 李丹阳 Department of Radiology Korea University Anam Hospital

摘要目的研究心房纤颤病人心脏MR成像上左心耳(LAA)血流与介入导管测定左心房压力(LAP)的关系。材料与方法本项回顾性研究获机构伦理委员会批准,所有病人

关键词： MR LAA 左心耳

A Privacy-Preserving Image Retrieval Based on AC-Coefficients and Color Histograms in Cloud Environment

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Computers, Materials & Continua 2019年第1期58卷 27-43页

作者： Zhihua Xia Lihua Lu Tong Qiu H.j.shim Xianyi Chen Byeungwoo jeon jiangsu Engineering Centre of Network Monitoring Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment TechnologySchool of Computer and SoftwareNanjing University of Information Science&TechnologyNanjing210044China College of Information&Communication Engineering Sungkyunkwan UniversityKorea

Content based image retrieval(CBIR)techniques have been widely deployed in many applications for seeking the abundant information existed in *** to large amounts of storage and computational requirements of CBIR,outsourcing image search work to the cloud provider becomes a very attractive option for many owners with small ***,owing to the private content contained in images,directly outsourcing retrieval work to the cloud provider apparently bring about privacy problem,so the images should be protected carefully before *** paper presents a secure retrieval scheme for the encrypted images in the YUV color *** this scheme,the discrete cosine transform(DCT)is performed on the Y *** resulting DC coefficients are encrypted with stream cipher technology and the resulting AC coefficients as well as other two color components are encrypted with value permutation and position *** the image owner transmits the encrypted images to the cloud *** receiving a query trapdoor form on query user,the server extracts AC-coefficients histogram from the encrypted Y component and extracts two color histograms from the other two color *** similarity between query trapdoor and database image is measured by calculating the Manhattan distance of their respective ***,the encrypted images closest to the query image are returned to the query user.

关键词： Image retrieval AC-coefficients histogram color histogram discrete cosine transform

Development of mathematical model with a genetic algorithm for automatic arc welding process

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Acta Metallurgica Sinica(English Letters) 2010年第3期23卷 230-240页

作者： D.T.Thao I.S.Kim j.W.jeong j.H.Lee j.Y.shim H.H.Kim Department of Mechanical Engineering Mokpo National University

This paper is to represent new algorithms to predict process parameters on top-bead width in robotic gas metal arc（GMA） welding *** models have been developed：linear, curvilinear and intelligent model based on full factorial design with two *** analysis was employed for optimization of the coefficients of linear and curvilinear models, while genetic algorithm（GA） was utilized to estimate the coefficients of an intelligent *** only the fitting of these models were checked and compared by using a variance test（ANOVA）, but also the prediction on top-bead width using the developed models were carried out based on the additional *** developed models were employed to investigate the characteristic between process parameters and top-bead *** solutions and graphical representation showed that the intelligent model developed can be employed for prediction of bead geometry in GMA welding process.

关键词： Top-bead width Genetic algorithm Multiple regression Robotic arc welding GMA welding

Overview of surface ozone variability in East Asia-North Pacific region during IGAC/APARE(1994—1996)

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journal of Environmental Sciences 2004年第4期16卷 599-609页

作者： K.S. Lam T.j.Wang T. Wang j. Tang . Y.Kajii C.M. Liu S.G. shim Environmental Engineering Unit Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hong Kong Department of Atmospheric Science Nanjing University Nanjing 210093 China Chinese Academy of Meteorological Science Beijing 100081 China Research Center for Advanced Science and Technology University of Tokyo Tokyo Japan Department of Atmospheric Science "National" Taiwan University Taipei Taiwan China Global Environmental Research Center Korea Institute of Science and Technology Seoul South Korea

Surface ozone(O\-3) was measured at Oki Island(japan), Cheju Island(South Korea), Lanyu Island(Taiwan Province, China), Cape D'Aguilar(Hong Kong SAR) and Lin'an, Longfenshan, Waliguan(China mainland) during january 1994—December 1996 as a component of IGAC/APARE(International Global Atmospheric Chemistry/East Asia-North Pacific Regional Experiment). This paper gave a joint discussion on the observational results at these stations over the study region. Investigations showed that the average of surface O 3 mixing ratios at the seven sites are 47.9±15.8, 48.1±17.9, 30.2±16.4, 31.6±17.5, 36.3±17.5, 34.8±11.5 and 48.2±9.5 ppbv, respectively. Significant diurnal variations of surface O 3 have been observed at Oki, Cheju, D’Aguilar, Lin'an and Longfenshan. Their annual averaged diurnal differences range from 8 to 23 ppbv and differ in each season. Surface O 3 at Lanyu and Waliguan do not show strong diurnal variability. Seasonal cycles of surface O 3 showed difference at the temperate and the subtropical remote sites. Oki has a summer minimum-spring maximum, while Lanyu has a summer minimum-autumn maximum. The suburban sites at D'Aguilar and Lin'an report high-level O 3 in autumn and low level O 3 in summer. Surface O 3 remains high in autumn and low in winter at the rural site Longfenshan. For the global background station Waliguan, surface O 3 exhibits a broad spring-summer maximum and autumn-winter minimum. The backward air trajectories to these sites have shown different pathways of long-range transport of air pollution from East Asia Continent to North Pacific Ocean. Surface O 3 was found to be strongly and positively correlated with CO at Oki and Lanyu, especially in spring and autumn, reflecting the substantial photochemical buildup of O\-3 on a regional scale. It is believed that the regional sources of pollution in East Asia have enhanced the average surface O 3 concentrations in the background atmosphere of North Pacific.

关键词： surface ozone trajectory transport photochemistry

Effect of Silicon on Arsenic Concentration and Speciation in Different Rice Tissues

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Pedosphere 2018年第3期28卷 511-520页

作者： LI Gang ZHENG Maozhong TANG jianfeng shim Hojae CAI Chao Key Lab of Urban Environment and Health Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021(China) Ningbo Urban Environment Observatory and Monitoring Station Ningbo 315830( China) College of Ecology and Resource Engineering Wuyi University Wuyishan 354300( China) University of Macao Taipa Macao SAR( China)

Rice is a major source of inorganic arsenic(As) exposure for billions of people worldwide. Therefore, strategies to reduce As accumulation in rice should be adopted. Silicon(Si) application can effectively mitigate As accumulation in rice. In this study, a pot experiment was performed to investigate the effect of Si on As speciation and distribution in different rice tissues. The results showed that Si addition significantly increased As and Si concentrations in soil solution and Si concentration in iron plaque formed around rice root surface, whereas As in the iron plaque was significantly decreased. Total As concentrations in the stem, leaf, husk, and brown rice were remarkably decreased by 51.9%, 31.9%, 33.8%, and 24.1%, respectively, after Si addition, and inorganic As concentrations were reduced by 52.3%, 35.5%, 50.1%, and 20.1%, respectively. Moreover, both dimethylarsinic acid concentration and percentage in rice grain were significantly elevated by Si application. Therefore, Si application is promising as a way to mitigate inorganic As accumulation in rice and to reduce consumer health risk.

关键词： arsenic accumulation contamination dimethylarsinic acid health risk inorganic arsenic iron plaque rice grain root surface

Organic photodiode with dual functions of indoor photovoltaic and high-speed photodetector

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Frontiers of Optoelectronics 2022年第2期15卷 45-51页

作者： Tae Wook Kim Sung Hyun Kim jae Won shim Do Kyung Hwang Center of Opto-Electronic Materials and Devices Post-Silicon Semiconductor InstituteKorea Institute of Science and Technology(KIST)Seoul02792Republic of Korea School of Electrical Engineering Korea UniversitySeoul02841Republic of Korea Division of Nano&Information Technology KIST SchoolUniversity of Science and Technology(UST)Seoul02792Republic of Korea

Energy harvesting and light detection are key technologies in various emerging optoelectronic *** high absorption capability and bandgap tunability of organic semiconductors make them promising candidates for such ***,a poly(3-hexylthiophene-2,5-diyl)(P3HT):indene-C60 bisadduct(ICBA)bulk heterojunction-based organic photodiode(OPD)was reported,demonstrating dual functionality as an indoor photovoltaic(PV)and as a high-speed *** OPD demonstrated decent indoor PV performance with a power conversion efficiency(PCE)of(11.6±0.5)%under a light emitting diode(LED)lamp with a luminance of 1000 *** a photodetector,this device exhibited a decent photoresponsivity of 0.15 A/W(green light)with an excellent linear dynamic range(LDR)of over 127 dB within the optical power range of 3.74×10^(−7) to 9.6×10^(−2) W/cm^(2).Furthermore,fast photoswitching behaviors could be observed with the rising/falling times of 14.5/10.4μs and a cutoff(3 dB)frequency of 37 *** results might pave the way for further development of organic optoelectronic applications.

关键词： Organic semiconductor Photodiode Indoor photovoltaics Photodetector

Disruption of Dhcr7 and Insig1/2 in cholesterol metabolism causes defects in bone formation and homeostasis through primary cilium formation

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Bone Research 2020年第1期8卷 39-52页

作者： Akiko Suzuki Kenichi Ogata Hiroki Yoshioka junbo shim Christopher AWassif Forbes DPorter junichi Iwata Department of Diagnostic&Biomedical Sciences The University of Texas Health Science Center at HoustonSchool of DentistryHoustonTXUSA Center for Craniofacial Research The University of Texas Health Science Center at HoustonSchool of DentistryHoustonTXUSA Division of Translational Medicine Eunice Kennedy Shriver National Institute of Child Health and Human DevelopmentBethesdaMDUSA Pediatric Research Center The University of Texas Health Science Center at HoustonMcGovern Medical SchoolHoustonTXUSA MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences HoustonTXUSA

Human linkage studies suggest that craniofacial deformities result from either genetic mutations related to cholesterol metabolism or high-cholesterol maternal diets. However, little is known about the precise roles of intracellular cholesterol metabolism in the development of craniofacial bones, the majority of which are formed through intramembranous ossification. Here, we show that an altered cholesterol metabolic status results in abnormal osteogenesis through dysregulation of primary cilium formation during bone formation. We found that cholesterol metabolic aberrations, induced through disruption of either Dhcr7(which encodes an enzyme involved in cholesterol synthesis) or Insig1 and Insig2(which provide a negative feedback mechanism for cholesterol biosynthesis), result in osteoblast differentiation abnormalities. Notably, the primary cilia responsible for sensing extracellular cues were altered in number and length through dysregulated ciliary vesicle fusion in Dhcr7 and Insig1/2 mutant osteoblasts. As a consequence, WNT/β-catenin and hedgehog signaling activities were altered through dysregulated primary cilium ***, the normalization of defective cholesterol metabolism by simvastatin, a drug used in the treatment of cholesterol metabolic aberrations, rescued the abnormalities in both ciliogenesis and osteogenesis in vitro and in vivo. Thus, our results indicate that proper intracellular cholesterol status is crucial for primary cilium formation during skull formation and homeostasis.

关键词： metabolism cholesterol homeostasis