• Title/Summary/Keyword: science exhibits

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Increase of Cdk5 and p35 during Retinoic Acid-Induced Neuronal Differentiation of SK-N-BE(2)C cells

  • Lee, Jong-Hee;Kim, Kyung-Tai
    • Proceedings of the Korean Biophysical Society Conference
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    • 2002.06b
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    • pp.46-46
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    • 2002
  • Cdk5, a neuronal Cdc2-like kinase, exhibits a variety of functions in neuronal differentiation and neurocytoskeleton dynamics as well as neuronal degeneration and cell death. However, its role in retinoic acid (RA)-induced differentiation has not been reported yet. We newly found that RA treatment of SK-N-BE(2)C, human neuroblastoma, increased expression of Cdk5 concomitantly with a neuronal specific activator, p35.(omitted)

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An Analysis of Organizational System and Management on Small Sized Local Science Museum during the COVID-19 Situation (코로나19 시기에 지방 소규모 과학관의 조직 및 운영 현황 분석)

  • Shin Han;Han-Ho Jeong;Hyoungbum Kim;Yonggi-Kim
    • Journal of the Korean Society of Earth Science Education
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    • v.16 no.1
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    • pp.133-142
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    • 2023
  • This study conducted qualitative research using Geochang Wolseong Space Creative Science Museum as a case study to investigate the organizational and operational status of small local science museums during the COVID-19 pandemic, as a basic study for the dissemination of scientific culture and public understanding of science. To analyze the situation of the science museum, an evaluation framework was developed, and information obtained through various communication channels and in-depth interviews with information commissioners of the museum were used for the study. As of 2020, when COVID-19 was at its peak, this science museum showed a clear decline in sales and visitor numbers compared to the previous year. Despite this situation, the museum was found to be using crisis management methods such as introducing unface-to-face programs, managing exhibits, and using various promotional media. However, the shortage of professional personnel, excessive workload of employees, and absence of differentiation from other science museums remain as challenges to be addressed in the future for sustainable earth science.

Characterization and Cytotoxic Activities of Nonadecanoic Acid Produced by Streptomyces scabiei subsp. chosunensis M0137 (KCTC 9927)

  • Yoo, Jin-Cheol;Han, Ji-Man;Nam, Seung-Kwan;Ko, Ok-Hyun;Park, Cheol-Hee;Kee, Keun-Hong;Sohng, Jae-Kyung;Jo, Jung-Sun;Seong, Chi-Nam
    • Journal of Microbiology
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    • v.40 no.4
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    • pp.331-334
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    • 2002
  • The substance 0116p, which exhibits cytotoxicity against human macrophage cell line THP-1, was isolated from a mycelial extract of Streptomyces scabiei subsp. chosunensis M0137. The cytotoxic substance was purified by Diaion-HP2O adsorption, solvent extraction, Sephadex LH-20 column chromatography, and silica-gel column chromatography. The molecular formula is C$\_$19/H$\_$38/O$\_$2/ (MW301.10) based on elemental and spectrometric analysis. It was identified as nonadecanoic acid by NMR spectral data. It exhibits cytotoxic activities in various human cancer cell lines, including A549, SK-OV-3, SK-MEL-2 and HCT-15. In addition, 0116p also inhibits IL-12 production in lipopolysaccharide-activated macrophages.

Microwave-assisted Preparation, Structures, and Photoluminescent Properties of [Ln(NO3)2(H2O)3(L)2](NO3)(H2O) {Ln=Tb, Eu;L=2-(4-pyridylium)ethanesulfonate, (4-pyH)+-CH2CH2-SO3-}

  • Zheng, Zhen Nu;Lee, Soon-W.
    • Bulletin of the Korean Chemical Society
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    • v.32 no.6
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    • pp.1859-1864
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    • 2011
  • Two lanthanide complexes, $[Ln(NO_3)_2(H_2O)_3(L)_2](NO_3)(H_2O)$ {Ln = Eu (1), Tb (2); L = 2-(4-pyridylium)-ethanesulfonate, $(4-pyH)^+-CH_2CH_2-SO_3^-)$}, were prepared from lanthanide nitrate and 4-pyridineethanesulfonic acid in $H_2O$ under microwave-heating conditions. Complexes 1 and 2 are isostructural, and the lanthanide metal in both complexes is coordinated to nine oxygen atoms. The pyridyl nitrogen in the ligand is protonated to give a zwitter ion that possesses an $NH^+$ (pyridyl) positive end and an $SO_3^-$ negative end. All O-H and N-H hydrogen atoms participate in hydrogen bonds to generate a two-dimensional (complex 1) or a three-dimensional network (complex 2). Complex 1 exhibits an intense red emission, whereas complex 2 exhibits an intense green emission in the solid state at room temperature.

A Study for Exhibition and Education Programs of the National Assembly Library: Focusing on Larchiveum Model (국회도서관 전시·교육프로그램 운영방안에 관한 연구 - 라키비움 운영모델을 중심으로 -)

  • Park, OkNam;Park, HeeJin
    • Journal of the Korean Society for Library and Information Science
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    • v.51 no.1
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    • pp.201-226
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    • 2017
  • The National Assembly Library and its institutions need an integrated exhibition and education programs in order to provide all types of information resources which they produce, manage and preserve as part of history and evidence of democracy. This study aims to present the exhibition and education programs for National Assembly Library based on Larchiveum model. an integrated concept of library, archive, and museum. This study analyzed exhibits and education programs of various national libraries, archives, and related institutions and suggested exhibition and education programs for National Assembly Library based on Larchiveum model.

Role of HIV Vpr as a Regulator of Apoptosis and an Effector on Bystander Cells

  • Moon, Ho Suck;Yang, Joo-Sung
    • Molecules and Cells
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    • v.21 no.1
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    • pp.7-20
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    • 2006
  • The major event in human immunodeficiency virus type 1 (HIV-1) infection is the death of many cells related to host immune response. The demise of these cells is normally explained by cell suicide mechanism, apoptosis. Interestingly, the decrease in the number of immune cells, such as non-CD4+ cells as well as CD4+ T cells, in HIV infection usually occurs in uninfected bystander cells, not in directly infected cells. It has, therefore, been suggested that several soluble factors, including viral protein R (Vpr), are released from the infected cells and induce the death of bystander cells. Some studies show that Vpr interacts directly with adenine nucleotide translocator (ANT) to induce mitochondrial membrane permeabilization (MMP). The MMP results in release of some apoptogenic factors such as cytochrome-c (cyt-c) and apoptosis-inducing factor (AIF). Vpr also has indirect effect on mitochondria through enhancing the level of caspase-9 transcription and suppressing nuclear factor-kappa B (NF-${\kappa}B$). The involvement of p53 in Vpr-induced apoptosis remains to be studied. On the other hand, low level of Vpr expression has anti-apoptotic effect, whereas it's high level of expression induces apoptosis. Extracellular Vpr also exhibits cytotoxicity to uninfected bystander cells through apoptotic or necrotic mechanism. The facts that Vpr has cytotoxic effect on both infected cells and bystander cells, and that it exhibits both proand anti-apoptotic activity may explain its role in viral survival and disease progression.

Biomechanical Characteristic on Lower Extremity with or without Chronic Ankle Instability during Double Leg Drop Landing (양발 드롭랜딩 시 만성적인 발목 불안정성 유무에 따른 하지주요관절의 역학적 특성)

  • Jeon, Kyoungkyu;Park, Jinhee
    • Korean Journal of Applied Biomechanics
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    • v.31 no.2
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    • pp.113-118
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    • 2021
  • Objective: The purpose of this study was to investigate differences of landing strategy between people with or without chronic ankle instability (CAI) during double-leg drop landing. Method: 34 male adults participated in this study (CAI = 16, Normal = 18). Participants performed double-leg drop landing task on a 30 cm height and 20 cm horizontal distance away from the force plate. Lower Extremities Kinetic and Kinematic data were obtained using 8 motion capture cameras and 2 force plates and loading rate was calculated. Independent samples t-test were used to identify differences between groups. Results: Compared with normal group, CAI group exhibits significantly less hip internal rotation angle (CAI = 1.52±8.12, Normal = 10.63±8.44, p = 0.003), greater knee valgus angle (CAI = -6.78±5.03, Normal = -12.38 ±6.78, p = 0.011), greater ankle eversion moment (CAI = 0.0001±0.02, Normal = -0.03±0.05, p = 0.043), greater loading Rate (CAI = 32.65±15.52, Normal = 18.43±10.87, p = 0.003) on their affected limb during maximum vertical Ground Reaction Force moment. Conclusion: Our results demonstrated that CAI group exhibits compensatory movement to avoid ankle inversion during double-leg drop landing compared with normal group. Further study about how changed kinetic and kinematic affect shock absorption ability and injury risk in participants with CAI is needed.

UV Responsive Characteristics of n-Channel Schottky Barrier MOSFET with ITO as Source/Drain Contacts

  • Kim, Tae-Hyeon;Lee, Chang-Ju;Kim, Dong-Seok;Sung, Sang-Yun;Heo, Young-Woo;Lee, Jung-Hee;Hahm, Sung-Ho
    • Journal of Sensor Science and Technology
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    • v.20 no.3
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    • pp.156-161
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    • 2011
  • We fabricated a schottky barrier metal oxide semiconductor field effect transistor(SB-MOSFET) by applying indium-tin-oxide(ITO) to the source/drain on a highly resistive GaN layer grown on a silicon substrate. The MOSFET, with 10 ${\mu}M$ gate length and 100 ${\mu}M$ gate width, exhibits a threshold gate voltage of 2.7 V, and has a sub-threshold slope of 240 mV/dec taken from the $I_{DS}-V_{GS}$ characteristics at a low drain voltage of 0.05 V. The maximum drain current is 18 mA/mm and the maximum transconductance is 6 mS/mm at $V_{DS}$=3 V. We observed that the spectral photo-response characterization exhibits that the cutoff wavelength was 365 nm, and the UV/visible rejection ratio was about 130 at $V_{DS}$ = 5 V. The MOSFET-type UV detector using ITO, has a high UV photo-responsivity and so is highly applicable to the UV image sensors.

Effect of Heat Treatment on Microstructure and Mechanical Properties of an Fe-6.5Mn-0.08C Medium-Manganese Steel (열처리에 따른 Fe-6.5Mn-0.08C 중망간강의 미세조직과 기계적 특성)

  • Yoon, Young-Chul;Lee, Sang-In;Hwang, Byoungchul
    • Korean Journal of Materials Research
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    • v.30 no.1
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    • pp.8-13
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    • 2020
  • Effect of heat treatment on microstructure and mechanical properties of an Fe-6.5Mn-0.08C medium-manganese steel is investigated in this study. Three kinds of medium-manganese steel specimens are fabricated by varying heat treatments of intermediate quenching (IQ), step quenching (SQ), and intercritical annealing (IA). Hardness and tensile tests are performed to examine the correlation of microstructure and mechanical properties for the Fe-6.5Mn-0.08C medium-manganese steel specimens. The IQ and SQ specimens have microstructures of martensite matrix with ferrite, whereas IA specimen exhibits microstructure of acicular ferrite matrix with martensite. The tensile test results show that the SQ specimen with martensite matrix has the highest yield strength and the lowest elongation. On the other hand, the SQ specimen has the highest hardness due to the relatively lower reduction of carbon content in martensite during intercritical annealing. According to the fractography of tensile tested specimens, the SQ specimen exhibits a dimple and quasi-cleavage fracture appearance while the IQ and IA specimens have fully ductile fracture appearance with fine-sized dimples caused by microvoid coalescence at ferrite and martensite interface.