Who Becomes Exposed to Celebrity Activism on Twitter?

Seulgi Jang,Yujin Kim,Byung Joon Lee,Kyu S. Hahn 한국언론학회 2015 Asian Communication Research Vol.12 No.1

Twitter has significantly amplified celebrity presence on civic affairs. Although celebrities hold little expertise on policy affairs, they can be quite influential since their popularity allows them to reach large audiences. There is an ongoing debate concerning the democratic implications of increasing celebrity influence in policy affairs. In the current study, taking Oisoo Lee as a test case, we investigate the political implications of celebrity following on Twitter. We first compare Lee’s followers with those of ten news outlets, based on the co-following pattern among 1,442,317 Twitter users. We also had access to supplementary survey data on 11,725 members of an online survey panel who had provided their Twitter screen names. For these survey participants, we are able to match their following behavior with individual level attributes. Our results reveal that Lee’s followers are not ideologically skewed in either direction. Indeed, our survey findings confirmed that a vast majority of Lee’s followers identified themselves as independent. On the other hand, survey results show that Oisoo Lee is more likely to attract those lacking the ability to process one-sided information in a balanced manner. This raises a concern that they could be easily misinformed or misled.

Solution-processable method for producing high-quality reduced graphene oxide displaying ‘self-catalytic healing’

Lee, Geonhee,Jung, Du Won,Lee, Wonki,Nah, Sanghee,Ji, Seulgi,Hwang, Jun Yeon,Lee, Sun Sook,Park, Sungsu,Chae, Soo Sang,Lee, Jeong-O Elsevier 2019 Carbon Vol.141 No.-

<P><B>Abstract</B></P> <P>Reduced graphene oxide (rGO) has potential as a mass-producible and cost-effective substitute for graphene, but displays poor crystal quality due to various types of structural defects. Though many attempts have been reported to improve the quality of rGO, most of them require sophisticated equipment or severe conditions such as toxic chemicals, high temperature, and electron beam or plasma treatment in ultra-high vacuum (UHV) conditions. Here, we report a mild and simple solution-based healing method for obtaining high-quality rGO, with this method involving the use of a simple camera flash light treatment and the nontoxic chemicals <SMALL>L</SMALL>-ascorbic acid and ethanol. Exposing a GO solution containing <SMALL>L</SMALL>-ascorbic acid and ethanol to the flash light irradiation for a short amount of time (<10 min) resulted in the formation of rGO displaying high quality both with respect to its chemical composition and its crystallinity. To elucidate the mechanism of the flash-light-induced healing of rGO, we acquired and analyzed the transient absorption spectrum for the healing reaction by using femtosecond pump-probe spectroscopy; this analysis revealed the photo-catalytic activity of GO by itself to repair chemical and topological defects, and we hence named this process ‘self-catalytic healing’.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Microbial Genome Mining for the Development of Novel CO₂-utilization Modules

Seulgi KANG,Hyeonsik LEE,Jiyun BAE,Sangrak JIN,Donghwi LEE,Garam JEONG,You-Jung JUNG,Hyeokjun YOON,Moonsuk HUR,Byoung-Hee LEE,Jong-Geol KIM,Hyo Jeong LEE,Che Ok JEON,Suhyung CHO,Byung-Kwan CHO 한국생물공학회 2023 한국생물공학회 학술대회 Vol.2023 No.4

Active Directory 환경에서의 침해사고 동향 분석 및 활용방안

이슬기(Seulgi Lee),김가영(Kayoung Kim),김동욱(Dongwook Kim),이태우(Taewoo Lee),이재광(JaeKwang Lee) 한국정보보호학회 2021 情報保護學會誌 Vol.31 No.3

기업 내부 전산망을 관리하는데 용이한 Active Directory(AD) 환경이 보편적으로 사용되는 가운데, 적절치 않은 정책설정으로 대형 침해사고로 이어지는 경우가 발생하고 있다. AD는 다수 시스템과 사용자 등 자원을 관리하기 효율적이라는 장점이 있지만, 핵심 권한을 탈취당하면, 모든 자원에 접근할 수 있다는 반작용도 존재한다. 한국인터넷진흥원은 기업의 보안성 제고를 위하여 AD 환경에서 발생하는 침해사고를 상세히 분석하고 최신 동향을 지속적으로 공유하고 있다. 하지만, 침해사고 보고서는 사업 특성 및 구축환경의 다양성으로 인하여 획일화된 대응 전략을 제시할 수 없으며, 기업에 특화된 적용방안은 각자 마련해야 한다. 본고에서는 공개된 보고서를 기업 환경에 적용하기 어렵다는 문제를 해결하기 위하여 최근 발생한 AD 환경에서의 침해사고를 분석하고, 각 기업에서 어떻게 활용할 수 있는지 방안을 제시한다.

사이버 위협 인텔리전스 환경에서의 종합분석 전략

이슬기(Seulgi Lee),김동욱(Dongwook Kim),김병재(Byeongjae Kim),이태우(Taewoo Lee),한상원(Sangwon Han),이재광(JaeKwang Lee) 한국정보보호학회 2021 情報保護學會誌 Vol.31 No.5

한국인터넷진흥원 종합분석팀은 사이버 위협 인텔리전스(CTI)를 통해 주요 침해사고를 추적하여 분석하고 이에 대한 대응방안을 마련, 공유하는 역할을 수행하고 있다. 구체적으로는 외부 협력채널 혹은 기존 사고에서 사용된 악성도구의 흔적을 기반으로 악성 인프라를 탐지하고, 이에 대한 공격자의 전략을 상세히 분석, 정리한 보고서를 발간하여 기업의 보안수준을 제고하려 노력하고 있다. 본고에서는 사이버 위협 인텔리전스 측면에서 변화한 종합분석의 관점 및 역할을 소개하고, 고도화되어가는 침해사고를 대응하기 위한 향후 전략을 제안한다.

저수지 조기경보체계 현황 분석

이슬기(Lee, Seulgi),이승수(Lee, Sungsu),배민기(Bae, Min Ki),이선영(Lee, Seonyoung) 대한토목학회 2022 대한토목학회 학술대회 Vol.2022 No.10

Brain correlates to facial motor imagery and its somatotopy in the primary motor cortex

Soliman, Ramy S.,Lee, Sanghoon,Eun, Seulgi,Mohamed, Abdalla Z.,Lee, Jeungchan,Lee, Eunyoung,Makary, Meena M.,Kathy Lee, Seung Min,Lee, Hwa-Jin,Choi, Woo Suk,Park, Kyungmo Wolters Kluwer Health | Lippincott Williams Wilkin 2017 NEUROREPORT - Vol.28 No.5

<P>Motor imagery (MI) has attracted increased interest for motor rehabilitation as many studies have shown that MI shares the same neural networks as motor execution (ME). Nevertheless, MI in terms of facial movement has not been studied extensively; thus, in the present study, we investigated shared neural networks between facial motor imagery (FMI) and facial motor execution (FME). In addition, FMI somatotopy within-face was investigated between the forehead and the mouth. Functional MRI was used to examine 34 healthy individuals with ME and MI paradigms for the forehead and the mouth. The general linear model and a paired t-test were performed to define the facial area in the primary motor cortex (M1) and this area has been used to investigate somatotopy between the forehead and mouth FMI. FMI recruited similar brain motor areas as FME, but showed less neural activity in all activated regions. The facial areas in M1 were distinguishable from other body movements such as finger movement. Further investigation of this area showed that forehead and mouth imagery tended to lack a somatotopic representation for position on M1, and yet had distinct characteristics in terms of neural activity level. FMI showed different characteristics from general MI as the former exclusively activated facial processing areas. In addition, FME and FMI showed different characteristics in terms of BOLD signal level, while sharing the same neural areas. The results imply a potential usefulness of MI training for rehabilitation of facial motor disease considering that forehead and mouth somatotopy showed no clear position difference, and yet showed a significant BOLD signal intensity variation. NeuroReport 28: 285-291 Copyright (C) 2017 Wolters Kluwer Health, Inc. All rights reserved.</P>

Long-term air-stable Au doping of graphene by layer-by-layer assembly with graphene oxide for flexible transparent electrodes

Lee, Su Jin,Lim, Yi Rang,Ji, Seulgi,Kim, Seong Ku,Yoon, Yeoheung,Song, Wooseok,Myung, Sung,Lim, Jongsun,An, Ki-Seok,Park, Jin-Seong,Lee, Sun Sook Elsevier 2018 Carbon Vol.126 No.-

<P><B>Abstract</B></P> <P>In order to realize the most suitable hybrid structure for air-stable graphene-based transparent and flexible electrodes, we systematically compared graphene oxide (GO)/Au/graphene and graphene/Au/GO hybrid films fabricated by layer-by-layer assembly. The sheet resistance of graphene/Au/GO was proportional to the concentration of AuCl<SUB>3</SUB> (1–5 mg/ml), which can be understood by a significant blue-shift in the G-band associated with the phonon stiffening. The size and density of formed Au nanoparticles strongly influenced their reduction reaction, which is a crucial factor for maximizing the doping effects. The optimized optical transmittance and sheet resistance of GO/Au/graphene were 94.9% and 198 ± 29 Ohm/sq, respectively. Furthermore, the hybrid films revealed stable doping effects (sheet resistance variation: 23–55%) against ambient conditions after 1 month. The variation in sheet resistance for GO/Au/graphene hybrid films corresponds to 30% with a bending radius of 10 mm after repeated bending tests (bending cycles of 10<SUP>5</SUP>).</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Anion-Directed Coordination Networks of a Flexible S-Pivot Ligand and Anion Exchange in the Solid State

Lee, Eunji,Ju, Huiyeong,Kim, Seulgi,Park, Ki-Min,Lee, Shim Sung The American Chemical Society 2015 CRYSTAL GROWTH AND DESIGN Vol.15 No.11

<P>Using an S-pivot joint flexible ligand bis(4-cyanobenzyl)sulfide (bcbs), three silver(I) complexes [Ag(bcbs)ClO<SUB>4</SUB>]<SUB><I>n</I></SUB> (<B>1</B>), [Ag<SUB>2</SUB>(bcbs) (CF<SUB>3</SUB>CO<SUB>2</SUB>)<SUB>2</SUB>]<SUB><I>n</I></SUB> (<B>2</B>), and {[Ag<SUB>3</SUB>(bcbs)<SUB>4</SUB>](PF<SUB>6</SUB>)<SUB>3</SUB>·4CH<SUB>2</SUB>Cl<SUB>2</SUB>}<SUB><I>n</I></SUB> (<B>3</B>) have been isolated. Configurations (“V”-, “L”-, and “W”-shapes) of the bcbs ligand in <B>1</B>–<B>3</B> can be tuned as a result of changing the anions of the silver(I) salts, which ultimately form a series of infinite low to high dimensional frameworks with different structures. The perchlorato compound <B>1</B> shows a stairway type 1-D ribbon structure, in which the anion acts as a monodentate terminal ligand. The bcbs ligand in <B>1</B> shows a gauche–anti arrangement, adopting an L-shape configuration. The π–π stacking interaction between adjacent ribbons in <B>1</B> yields a pseudo-2-D structure with a herringbone pattern. Compound <B>2</B> is composed of silver(I)–bcbs helical channels, which are further interlinked via monodentate bridging CF<SUB>3</SUB>CO<SUB>2</SUB><SUP>–</SUP> ions forming a 3-D multichannel framework with a <B>dmd</B> topology. Unlike <B>1</B>, the bcbs ligand in <B>2</B> shows an anti–anti arrangement, adopting a W-shape configuration. The corresponding PF<SUB>6</SUB><SUP>–</SUP> complex <B>3</B> exhibits a 2-fold interpenetrated 3-D framework. The preferred anion-free structure in <B>3</B> presumably reflects the strong coordination of the donor set and the weak affinity of the PF<SUB>6</SUB><SUP>–</SUP> toward the metal center. Similar to <B>1</B>, the bcbs ligand in <B>3</B> adopts an L-shape configuration. In this work, the structural variations of the resulting coordination polymers are mainly associated with the diverse configurations of the flexible ligand, as well as the different coordination modes and abilities for the anions. Anion exchange accompanying an irreversible structural conversion from <B>2</B> or <B>3</B> to <B>1</B> was monitored in the crystalline state by IR and PXRD studies. AFM images and height profiles for the crystal surface before and after the anion-exchange were observed. On the basis of the above measurements, a mechanistic process from the 3-D structured <B>3</B> (PF<SUB>6</SUB><SUP>–</SUP> form) to the 1-D structured <B>1</B> (ClO<SUB>4</SUB><SUP>–</SUP> form) by the anion exchange was also proposed.</P><P>An anion effect on the silver(I) coordination networks with a flexible ligand and their anion-exchange which shows a perchlorate selectivity are reported.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/cgdefu/2015/cgdefu.2015.15.issue-11/acs.cgd.5b01050/production/images/medium/cg-2015-01050x_0001.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/cg5b01050'>ACS Electronic Supporting Info</A></P>

Identification of the Antidepressant Vilazodone as an Inhibitor of Inositol Polyphosphate Multikinase by Structure-Based Drug Repositioning

Lee, Boah,Park, Seung Ju,Lee, Seulgi,Park, Seung Eun,Lee, Eunhye,Song, Ji-Joon,Byun, Youngjoo,Kim, Seyun Korean Society for Molecular and Cellular Biology 2020 Molecules and cells Vol.43 No.3

Inositol polyphosphate multikinase (IPMK) is required for the biosynthesis of inositol phosphates (IPs) through the phosphorylation of multiple IP metabolites such as IP3 and IP4. The biological significance of IPMK's catalytic actions to regulate cellular signaling events such as growth and metabolism has been studied extensively. However, pharmacological reagents that inhibit IPMK have not yet been identified. We employed a structure-based virtual screening of publicly available U.S. Food and Drug Administration-approved drugs and chemicals that identified the antidepressant, vilazodone, as an IPMK inhibitor. Docking simulations and pharmacophore analyses showed that vilazodone has a higher affinity for the ATP-binding catalytic region of IPMK than ATP and we validated that vilazodone inhibits IPMK's IP kinase activities in vitro. The incubation of vilazodone with NIH3T3-L1 fibroblasts reduced cellular levels of IP5 and other highly phosphorylated IPs without influencing IP4 levels. We further found decreased Akt phosphorylation in vilazodone-treated HCT116 cancer cells. These data clearly indicate selective cellular actions of vilazodone against IPMK-dependent catalytic steps in IP metabolism and Akt activation. Collectively, our data demonstrate vilazodone as a method to inhibit cellular IPMK, providing a valuable pharmacological agent to study and target the biological and pathological processes governed by IPMK.