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Spectral Dependence on the Correction Factor of Erythemal UV for Cloud, Aerosol, Total Ozone, and Surface Properties: A Modeling Study

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Advances in Atmospheric Sciences 2016年第7期33卷 865-874页

作者： sang seo park Yeonjin JUNG Yun Gon LEE Research Institute for Applied Mechanics Kyushu University Department of Atmospheric Sciences Yonsei University Department of Atmospheric Sciences Chungnam National University

Radiative transfer modal simulations were used to investigate the erythemal ultraviolet （EUV） correction factors by separating the UV-A and UV-B spectral ranges. The correction factor was defined as the ratio of EUV caused by changing the amounts and characteristics of the extinction and scattering materials. The EUV correction factors （CFEUV） for UV-A [CFEUV（A）] and UV-B [CFEUV（B）] were affected by changes in the total ozone, optical depths of aerosol and cloud, and the solar zenith angle. The differences between CFEUV（A） and CFEUV（B） were also estimated as a function of solar zenith angle, the optical depths of aerosol and cloud, and total ozone. The differences between CFEUV（A） and CFEUV（B） ranged from -5.0% to 25.0% for aerosols, and from -9.5% to 2.0% for clouds in all simulations for different solar zenith angles and optical depths of aerosol and cloud. The rate of decline of CFEUV per unit optical depth between UV-A and UV-B differed by up to 20% for the same aerosol and cloud conditions. For total ozone, the variation in CFEUV（A） was negligible compared with that in CFEUV（B） because of the effective spectral range of the ozone absorption band. In addition, the sensitivity of the CFEUVs due to changes in surface conditions （i.e., surface albedo and surface altitude） was also estimated by using the model in this study. For changes in surface albedo, the sensitivity of the CFEUVs was 2.9%-4.1% per 0.1 albedo change, depending on the amount of aerosols or clouds. For changes in surface altitude, the sensitivity of CFEUV（B） was twice that of CFEUV（A）, because the Rayleigh optical depth increased significantly at shorter wavelengths.

关键词： Erythemal UV correction factor UV-A UV-B

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Impact of UV-A Radiation on Erythemal UV and UV-index Estimation over Korea

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Advances in Atmospheric Sciences 2015年第12期32卷 1639-1646页

作者： sang seo park Yun Gon LEE Jung Hyun KIM Department of Atmospheric Sciences Yonsei University Department of Atmospheric Sciences Chungnam National University

Because total UV （TUV） in the UV-A region is 100 times higher than in the UV-B region, UV-A is a considerable compo- nent when calculating erythemal UV （EUV） and UV-index. The ratio of EUV to TUV in the UV-A value [EUV（A）/TUV（A）] is investigated to convert the EUV（A） from TUV（A） for broadband observation. The representative value of EUV（A）/TUV（A）, from the simulation study, is 6.9 × 10^- 4 changing from 6.1 ×10^-4 to 7.0 × 10^ -4 as aerosol optical depth, total ozone and solar zenith angle change. By adopting the observational data of EUV（B） and TUV（A） from UV-biometer measurements at Yonsei University [（37.57°N, 126.95°E）, 84 m above sea level], the EUV irradiance increases to 15% of EUV（B） due to the consideration of EUV（A） from the data of TUV（A） observation. Compared to the total EUV observed from the Brewer spec- trophotometer at the same site, the EUV（B） from the UV-biometer observes only 95% of total EUV, and its underestimation is caused by neglecting the effect of UV-A. However, the sum of EUV（B） and EUV（A） [EUV（A＋B）] from two UV-biometers is 10% larger than the EUV from the Brewer spectrophotometer because of the spectral overlap effect in the range 320-340 nm. The correction factor for the overlap effect adjusts 8% of total EUV.

关键词： erythemal UV total UV UV-B UV-biometer

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Significant control of metal-insulator transition temperature through catalytic excessive oxygen doping in high-performance vanadium dioxide nanobeam channel

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Journal of Materials Science & Technology 2020年第9期44卷 96-101页

作者： Minhwan Ko sang Yeon Lee Jucheol park Hyungtak seo Department of Energy Systems Research Ajou UniversitySuwon16499Republic of Korea Gyeongbuk Science Technology Promotion Center Gumi Electronics&Information Technology Research InstituteGumi39717Republic of Korea Department of Materials Science and Engineering Ajou UniversitySuwon16499Republic of Korea

The strategy of a reliable transition temperature control of vanadium dioxide(VO2)is *** VO2 nanobeams were synthesized by a thermal chemical vapor deposition(TCVD)*** metal-insulator transition(MIT)temperature increases to above 380K when the TiO2 ratio of the source is 5 at.%,although the Ti source is not physically doped into VO2 *** XPS spectra of the V 2p orbital reveal the excessive oxidation of V after the TCVD processes with a higher TiO2 ratio,indicating that the TiO2 precursor is important in the O-doping of the surface V O bonds when forming volatile Ti-O gas ***,TiO2 reactants can be used as a VO2 surface chemical modifier to manipulate the MIT transition temperature and maintain a homogenous VO2 phase,which is useful for a Mott device application with a record on/off switching ratio>104 and Mott transition temperature>380 K.

关键词： VO2 Mott transition Metal-insulator transition temperature Oxygen doping Titanium catalyst

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Effect of ZnO Electrodeposited on Carbon Film and Decorated with Metal Nanoparticles for Solar Hydrogen Production

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Journal of Materials Science & Technology 2016年第10期32卷 1059-1065页

作者： Young Kwang Kim Hye-Jin seo Soonhyun Kim Sung-Ho Hwang Hyunwoong park sang Kyoo Lim Division of Nano and Energy Convergence Research Daegu Gyeongbuk Institute of Science and Technology (DGIST) School of Energy Engineering Kyungpook National University

In this study, we prepared horn-like ZnO structures on carbon films（ZnO/CF） by electrodeposition and decorated the ZnO horns with different metals（Ag, Au, and Pt） via photodeposition（M-ZnO/CF）. Using M-ZnO/CF as photocatalysts, we examined ways to enhance solar hydrogen production from various points of view, such as modifying the intrinsic physical properties and thermodynamics of the materials, and varying the chemical environment during M-ZnO/CF fabrication. In particular, we focused on the effects of the carbon film and metals in M-ZnO/CF hybrid photocatalysts on solar hydrogen production. The type of metal nanoparticles is an important factor in solar hydrogen production because the deposition rate and electrical conductivity of each metal affect the proton-water reduction ability.

关键词： Solar hydrogen production ZnO horn Carbon film Metal nanoparticle Electrodeposition

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Neuroprotective Effect of Chunghyuldan(Qing Xue Dan)on Hypoxia-Reoxygenation Induced Damage of Neuroblastoma 2a Cell Lines

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Chinese Journal of Integrative Medicine 2013年第12期19卷 940-944页

作者： Chang-Nam Ko In-seo park seong-Uk park Woo-sang Jung sang-Kwan Moon Jung-Mi park Chulhun Kang Ki-Ho Cho Department of Cardiology and Neurology Diseases College of Korean MedicineKyung Hee University Department of Medical Science Graduate School of East-West Medical ScienceKyung Hee University

Objectives： Chunghyuldan （CHD）, a combinatorial drug that has anti-hyperlipidemic and anti inflammatory activities, has been shown to reduce infarct volume in a focal ischemia-reperfusion rat model. To explore the molecular basis of CHD＇s neuroprotective effect, we examined whether CHD shows a cell-protective activity and has a regulatory effect on Bax and/or B-cell leukemia/lymphoma 2 （Bcl-2） expression in mouse neuroblastoma 2a （N2a） cells subjected to hypoxia-reoxygenation （H/R）. Methods： In order to evaluate the effects of CHD on the cytotoxicity induced from hypoxia or H/R condition, lactate dehydrogenase （LDH） assay was performed. To explore whether the suppression of neural damage when pre-treated with CHD is associated with its anti-apoptotic effect, the CHD effect on the expression of Bcl-2 and Bax was analyzed by Western blotting analysis. Results： Cytotoxicity of N2a cell line was slightly increased in 42 h hypoxia condition and dramatically increased under the H/R condition. CHD treatment markedly decreased the cytotoxicity in both conditions （P〈0.01, P〈0.05）. H/R markedly increased the expression of the pro-apoptotic protein, Bax, but slightly increased the expression of the anti-apoptotic protein, Bcl-2, compared with the normoxia or hypoxia group. CHD significantly decreased Bax expression （P〈0.01） and slightly decreased Bcl-2 expression （P〉0.05）, resulted in a reduction of Bax/Bcl-2 ratio in N2a cells subjected to H/R. Conclusion： CHD has neuroprotective effect in N2a cells subjected to H/R, which might be derived at least in part from its ability to decrease the expression of the pro-apoptotic protein, Bax.

关键词： apoptosis stroke Chunghyuldan herbal

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ESR2–HDA6 complex negatively regulates auxin biosynthesis to delay callus initiation in Arabidopsis leaf explants during tissue culture

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Plant Communications 2024年第7期5卷 200-214页

作者： Kyounghee Lee Hobin Yoon Ok-Sun park Jongbu Lim sang-Gyu Kim Pil Joon seo Department of Chemistry Seoul National UniversitySeoul 08826Korea Research Institute of Basic Sciences Seoul National UniversitySeoul 08826Korea Interdisciplinary Program in Agricultural Biotechnology Seoul National UniversitySeoul 08826Korea Plant Genomics and Breeding Institute Seoul National UniversitySeoul 08826Korea Department of Biological Sciences KAISTDaejeon 34141Korea

Plants exhibit an astonishing ability to regulate organ regeneration upon *** of leaf explants promotes the biosynthesis of indole-3-acetic acid(IAA),which is polar-transported to excised regions,where cell fate transition leads to root founder cell specification to induce de novo root *** regeneration capacity of plants has been utilized to develop in vitro tissue culture ***,we report that IAA accumulation near the wounded site of leaf explants is essential for callus formation on 2,4-dichlorophenoxyacetic acid(2,4-D)-rich callus-inducing medium(CIM).Notably,a high concentration of 2,4-D does not compensate for the action of IAA because of its limited efflux;rather,it lowers IAA biosynthesis via a negative feedback mechanism at an early stage of in vitro tissue culture,delaying callus *** auxin negative feedback loop in CIM-cultured leaf explants is mediated by an auxin-inducible APETALA2 transcription factor,ENHANCER OF SHOOT REGENERATION 2(ESR2),along with its interacting partner HISTONE DEACETYLASE 6(HDA6).The ESR2–HDA6 complex binds directly to,and removes the H3ac mark from,the YUCCA1(YUC1),YUC7,and YUC9 loci,consequently repressing auxin biosynthesis and inhibiting cell fate transition on 2,4-D-rich *** findings indicate that negative feedback regulation of auxin biosynthesis by ESR2 and HDA6 interferes with proper cell fate transition and callus initiation.

关键词： auxin biosynthesis negative feedback loop ESR2 HDA6 YUCCA chromatin modification

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4-Hydroxycinnamic acid attenuates neuronal cell death by inducing expression of plasma membrane redox enzymes and improving mitochondrial functions

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Food Science and Human Wellness 2023年第4期12卷 1287-1299页

作者： Sujin park YoonA Kim Jaewang Lee Hyunsoo seo sang-Jip Nam Dong-Gyu Jo Dong-Hoon Hyun Department of Life Science Ewha Womans UniversitySeoul 03760South Korea Department of Chemistry and Nano Science Ewha Womans UniversitySeoul 03760South Korea School of Pharmacy Sungkyunkwan UniversitySuwon 16419South Korea

Many approaches to neurodegenerative diseases that focus on amyloid-βclearance and gene therapy have not been *** therapeutic applications focus on enhancing neuronal cell survival during the pathogenesis of neurodegenerative diseases,including mitochondrial *** membrane(PM)redox enzymes are crucial in maintaining cellular physiology and redox homeostasis in response to mitochondrial *** phytochemicals are known to induce the expression of detoxifying enzymes under stress *** this study,mechanisms of neuroprotective effects of 4-hydroxycinnamic acid(HCA)were examined by analyzing cell survival,levels of abnormal proteins,and mitochondrial functions in two different neuronal *** protected two neuronal cells exhibited high expression of PM redox enzymes and the consequent increase in the NAD^(+)/NADH *** cultured with HCA showed delayed apoptosis and decreased oxidative/nitrative damage accompanied by decreased ROS production in the *** increased the mitochondrial complexes I and II activities and ATP ***,HCA increased mitochondrial fusion and decreased mitochondrial ***,HCA maintains redox homeostasis and energy metabolism under oxidative/metabolic stress *** findings suggest that HCA could be a promising therapeutic approach for neurodegenerative diseases.

关键词： NADH-quinone oxidoreductase 1(NQO1) Cytochrome b5 reductase 4-Hydroxycinnamic acid Neuroprotection Improved mitochondrial functions

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Targeted down-regulation of Hipp1 ameliorates tau-induced deficits in Drosophila melanogaster

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Genes & Diseases 2023年第6期10卷 2248-2251页

作者： Sung Yeon park Jieun seo Seulbee Lee Joohyung Kim sang Jeong Kim Seungbok Lee Yang-Sook Chun Ischemic/Hypoxic Disease Institute Seoul National University College of MedicineSeoul 03080Republic of Korea Department of Biomedical Sciences Seoul National University College of MedicineSeoul 03080Republic of Korea Department of Physiology Seoul National University College of MedicineSeoul 03080Republic of Korea Department of Brain and Cognitive Sciences Seoul National UniversitySeoul 08826Republic of Korea Department of Cell and Developmental Biology and Dental Research Institute Seoul National UniversitySeoul 08826Republic of Korea

Tauopathies,such as Alzheimer's disease(AD),are neurodegenerative diseases characterized by the deposition of neurofibrillary tangles comprising hyperphosphorylated tau protein in the human brain.1 Given that abnormal epigenetic alterations in heterochromatin configuration have been documented in AD patients and transgenic animal models of AD,2 we investigated the roles of novel heterochromatin-associated interactors3 in *** transgenic flies via UAS-Gal4 binary system,we found that knockdown of Hipp1(HP1a and insulator partner protein-1)3 ***4ow(referred to as"tau"hereafter for simplicity)2-induced locomotion defects,reduced lifespan,and degeneration of brain ***,Hipp1 knockdown restored tau-driven aberrant expression of putative insulator targets and aberrant insulator-mediated epigenetic ***1 may have a role as an insulator-binding partner regarding being implicated in tauinduced neurodegeneration.

关键词： tau alterations degeneration

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Silent advanced large cell neuroendocrine carcinoma with synchronous adenocarcinoma of the colon:A case report

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World Journal of Gastrointestinal Oncology 2022年第11期14卷 2266-2272页

作者： Hyeon seok Baek sang Wook Kim Soo Teik Lee Ho Sung park Seung Young seo Department of Internal Medicine Research Institute of Clinical Medicine of Jeonbuk National University-Biomedical Research Institute of Jeonbuk National University HospitalJeonju-si 56445Jeollabuk-doSouth Korea Department of Pathology Jeonbuk National University Medical SchoolJeonjusi 56445Jeollabuk-doSouth Korea

BACKGROUND Large cell neuroendocrine carcinoma(LCNEC)accounts for about 0.25%of colorectal cancer ***,synchronous LCNEC and adenocarcinoma coexistence in the colon is very *** are usually aggressive and have a poor ***,colorectal LCNEC patients complain of abdominal symptoms such as pain,diarrhea or hematochezia because it is often diagnosed as an advanced disease that accompanies metastatic *** SUMMARY We describe a case of relatively asymptomatic synchronous LCNEC and colon adenocarcinoma.A 62-year-old male patient visited our hospital due to anemia detected by a local health *** did not complain of melena,hematochezia or abdominal *** examination was unremarkable and his abdomen was soft,nontender and nondistended with no palpable *** tests revealed anemia with hemoglobin 5.1 g/*** revealed an ulcerofungating lesion in the ascending colon and about a 1.5 cm-sized large sessile polyp in the sigmoid *** biopsy of the ascending colon lesion revealed the ulcerofungating mass that was LCNEC and endoscopic mucosal resection at the sigmoid colon lesion showed a large polypoid lesion that was *** liver,lung,bone and lymph nodes metastasis was found on chest/abdominal computed tomography and positron emission *** patient was diagnosed with advanced colorectal LCNEC with liver,lung,bone and lymph node metastasis(stage IV)and synchronous colonic adenocarcinoma *** this case,no specific symptom except anemia was observed despite the multiple *** patient refused systemic chemotherapy and was discharged after *** We report a case of silent LCNEC of the colon despite the advanced state and synchronous adenocarcinoma.

关键词： Large cell neuroendocrine carcinoma Colon Synchronous Adenocarcinoma Case report

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Reliable beacon transmission based MAC protocol for LR-WPANs over WLAN interferences

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第6期15卷 470-481页

作者： Ji-Hoon park Byung-seo KIM ITO Business Division Nongshim Data System Department of Computer and Information Communications Engineering Hongik University

The use of IEEE 802.15.4 standard based application systems has been rapidly increasing, for example, in medical services, sensor networks, public safety systems, and home automation systems. However, issues arise from the fact that IEEE 802.15.4 standard based low rate wireless personal area networks(LR-WPANs) use the same frequency bands as wireless local area networks(WLANs), and they interfere with each other. Based on past research on this issue, the interference has a more serious impact on LR-WPANs' performance than on WLANs' performance. In this paper we propose a method to improve LR-WPANs' performance while coexisting with WLANs, which is called the reliable beacon transmission based medium access control(MAC) protocol. Since the reliability of a beacon frame is important, in this method, only the beacon frame is transmitted in interference-free channels, and the data packets are transmitted in interfered channels instead of abandoning the channels altogether. This method increases the reliability of beacon frames as well as overall channel utilizations. The effectiveness of the proposed method was evaluated through extensive simulations, and this paper proves that this method improves the performance of IEEE 802.15.4 based wireless sensor networks(WSNs) over WLANs' interferences.

关键词： Low rate wireless personal area network(LR-WPAN) Interference Wireless local area network(WLAN) Beacon

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