Synthesis and Characterization of Organic Light-Emitting Copolymers Containing Naphthalene

Kim, Jung-Sik,Heo, Jun,Kang, Peng-Tao,Kim, Jin-Hak,Jung, Sung-Ouk,Kwon, Soon-Ki,Kim, Un-Kyung,Kim, Yun-Hi The Polymer Society of Korea 2009 Macromolecular Research Vol.17 No.2

Conjugated PPV-derived block copolymers containing 2-ethylhexyloxynaphthalene unit were synthesized and characterized in this study. The resulting polymers were soluble in common organic solvents and showed good thermal stabilities, The weight-average molecular weights ($M_w$) of the copolymers ranged from 246,000 to 475,000 with PDIs of $1.3{\sim}2.1$. The optical properties of these polymers, measured both in a chloroform solution and on a film, showed a maximum absorption at $405{\sim}476\;nm$ for Copolymers $I{\sim}VIII$. In the PL spectra, Copolymers $I{\sim}VIII$ showed maximum peaks at $510{\sim}566\;nm$. The HOMOs, LUMOs and band gaps of the PPV derivatives of Copolymers $I{\sim}VIII$ were $5.30{\sim}5.77$, $3.04{\sim}3.24$, and $2.5{\sim}2.2\;eV$, respectively, The multi-layered, light-emitting diodes of ITO/PEDOT/copolymers/LiF/Al exhibited turn-on voltages of $6{\sim}2.5\;V$ Copolymer VIII exhibited the maximum brightness of $3.657\;cd/m^2$. Particularly, Copolymer VII, with an identical composition of MEH-PPV and naphthalene-PPV, showed a maximum luminance efficiency and power efficiency of 2,63 cd/A and 1.06 lm/W, respectively.

Improvement of Milk Fatty Acid Composition for Production of Functional Milk by Dietary Phytoncide Oil Extracted from Discarded Pine Nut Cones (Pinus koraiensis) in Holstein Dairy Cows

Kim, Min Jeong,Jung, U Suk,Jeon, Seung Woo,Lee, Jae Sung,Kim, Won Seob,Lee, Sang Bum,Kim, Youn Chil,Kim, Bae Young,Wang, Tao,Lee, Hong Gu Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.12

This study was conducted to examine the effects of adding phytoncide oil extracted from Korean pine nut cone by-product to the diet of dairy cows on milk yield and compositions, fatty acid characteristics, complete blood count and stress response. A total of 74 Holstein cows were used for 30 days and divided into two groups. Each group was given a basal diet (C) or an experimental diet containing phytoncide additives at 0.016% (T) in feed. The results showed that phytoncide feeding had no effect on milk yield. In addition, there were no observed effects on milk composition, but the ratio of fatty acid in milk was significantly affected by the phytoncide diet, and it showed a positive effect. Not only were the major functional fatty acids, conjugated linoleic acid and eicosapentaenoic acid increased, but also ${\omega}6:{\omega}3$ fatty acid ratio was reduced in milk of T group (p<0.05). In blood analysis, the complete blood count showed no significant difference between C and T group on all parameters. However, the cortisol concentration was significantly decreased in T group compared to control (p<0.05). Taken together, we suggest that phytoncide oil does not have a great influence on the physiological changes, but can be a potential feed additive that improves the milk fatty acid and stress resilience in dairy cows. In addition, it will contribute to the development of feed resource, a reduction in feed cost and a lessening of environmental pollution.

Synthesis and Characterization of Organic Light-Emitting Copolymers Containing Naphthalene

Jung Sik Kim,Jun Heo,Peng Tao Kang,Jin Hak Kim,Sung Ouk Jung,Soon Ki Kwon,Un Kyung Kim,Yun Hi Kim 한국고분자학회 2009 Macromolecular Research Vol.17 No.2

Bacterial Community of Galchi-Baechu Kimchi Based on Culture-Dependent and - Independent Investigation and Selection of Starter Candidates

( Tao Kim ),( Sojeong Heo ),( Hong-eun Na ),( Gawon Lee ),( Jong-hoon Kim ),( Mi-sun Kwak ),( Moon-hee Sung ),( Do-won Jeong ) 한국미생물 · 생명공학회 2022 Journal of microbiology and biotechnology Vol.32 No.3

In this study, the bacterial community of galchi-baechu kimchi was determined using culture-based and culture-independent techniques (next generation sequencing:NGS), and showed discrepancies between results. Weissella koreensis and Pediococcus inopinatus were the dominant species according to the NGS results, while Bacillus species and P. inopinatus were dominant in the culture-dependent analysis. To identify safe starter candidates, sixty-five Bacillus strains isolated from galchi-baechu kimchi using culture-dependent methods were evaluated for their antibiotic resistance, presence of toxin genes, and hemolytic activity. Strains were then assessed for salt tolerance and protease and lipase activity. As a result, four strains-B. safensis GN5_10, B. subtilis GN5_19, B. velezensis GN5_25, and B. velezensis GT8-were selected as safe starter candidates for use in fermented foods.

Characterization of naturally Epstein-Barr virus-infected gastric carcinoma cell line YCCEL1

Kim, Do Nyun,Seo, Min Koo,Choi, Hoyun,Kim, Su Yeon,Shin, Hee Jong,Yoon, A-Ran,Tao, Qian,Rha, Sun Young,Lee, Suk Kyeong Microbiology Society 2013 The Journal of general virology Vol.94 No.3

<P>Epstein-Barr virus (EBV) is a herpesvirus associated with lymphomas and carcinomas. While EBV-associated epithelial cell lines are good model systems to investigate the role of EBV in carcinoma, only a few cell lines are available as they are hard to acquire. A greater variety of naturally EBV-infected cell lines which are derived from tumour patients are needed to represent various features of EBVaGC. We characterized cell line YCCEL1, established from a Korean EBVaGC patient, to ascertain whether it can be used to study the roles of EBV in EBVaGC. The expression of EBV genes and cell surface markers was examined by in situ hybridization, RT-PCR, Western blot analysis, immunofluorescence assay and Northern blot analysis. EBV episomal status was analysed by Southern blotting and real-time PCR. This cell line expressed EBV nuclear antigen 1 (EBNA1) and latent membrane protein 2A (LMP2A), but not EBNA2, LMP2B nor LMP1. The majority of the lytic proteins were not detected in YCCEL1 cells either before or after treatment with 12-O-tetradecanoylphorbol-13-acetate. YCCEL1 cells expressed BART microRNAs (miRNAs) at high level but did not express BHRF1 miRNAs. YCCEL1 cells expressed cytokeratin, but not CD21 and CD19, suggesting CD21-independent EBV infection. The latent EBV gene and EBV miRNA expression pattern of YCCEL1 cells closely resembled that of general EBVaGC cases. Our results support the value of YCCEL1 cells as a good model system to study the role of EBV in gastric carcinogenesis.</P>

Factors Affecting Customers’ Perceived Security and Trust in the Use of Electronic Payment Systems

Tao Wang,Changsu Kim,Ki-soo Kim 한국경영정보학회 2008 한국경영정보학회 학술대회논문집 Vol.2008 No.-

Characterization of Brain Dysfunction Induced by Bacterial Lipopeptides That Alter Neuronal Activity and Network in Rodent Brains

Kim, Kwang-Min,Zamaleeva, Alsu I.,Lee, Youn Woo,Ahmed, M. Rafiuddin,Kim, Eunkyung,Lee, Hye-Ryeon,Pothineni, Venkata Raveendra,Tao, Juan,Rhee, Siyeon,Jayakumar, Mithya,Inayathullah, Mohammed,Sivanesan, Society for Neuroscience 2018 The Journal of neuroscience Vol.38 No.50

<P>The immunopathological states of the brain induced by bacterial lipoproteins have been well characterized by using biochemical and histological assays. However, these studies have limitations in determining functional states of damaged brains involving aberrant synaptic activity and network, which makes it difficult to diagnose brain disorders during bacterial infection. To address this, we investigated the effect of Pam<SUB>3</SUB>CSK<SUB>4</SUB> (PAM), a synthetic bacterial lipopeptide, on synaptic dysfunction of female mice brains and cultured neurons in parallel. Our functional brain imaging using PET with [<SUP>18</SUP>F]fluorodeoxyglucose and [<SUP>18</SUP>F] flumazenil revealed that the brain dysfunction induced by PAM is closely aligned to disruption of neurotransmitter-related neuronal activity and functional correlation in the region of the limbic system rather than to decrease of metabolic activity of neurons in the injection area. This finding was verified by <I>in vivo</I> tissue experiments that analyzed synaptic and dendritic alterations in the regions where PET imaging showed abnormal neuronal activity and network. Recording of synaptic activity also revealed that PAM reorganized synaptic distribution and decreased synaptic plasticity in hippocampus. Further study using <I>in vitro</I> neuron cultures demonstrated that PAM decreased the number of presynapses and the frequency of miniature EPSCs, which suggests PAM disrupts neuronal function by damaging presynapses exclusively. We also showed that PAM caused aggregation of synapses around dendrites, which may have caused no significant change in expression level of synaptic proteins, whereas synaptic number and function were impaired by PAM. Our findings could provide a useful guide for diagnosis and treatment of brain disorders specific to bacterial infection.</P><P><B>SIGNIFICANCE STATEMENT</B> It is challenging to diagnose brain disorders caused by bacterial infection because neural damage induced by bacterial products involves nonspecific neurological symptoms, which is rarely detected by laboratory tests with low spatiotemporal resolution. To better understand brain pathology, it is essential to detect functional abnormalities of brain over time. To this end, we investigated characteristic patterns of altered neuronal integrity and functional correlation between various regions in mice brains injected with bacterial lipopeptides using PET with a goal to apply new findings to diagnosis of brain disorder specific to bacterial infection. In addition, we analyzed altered synaptic density and function using both <I>in vivo</I> and <I>in vitro</I> experimental models to understand how bacterial lipopeptides impair brain function and network.</P>

Traction Motor Design for In-Wheel type Electric Scooter

Tao Sun,Yong-Ho Kim,Soon-O Kwon,Hae-Jong Kim,Jae-Woo Jung,Jung-Pyo Hong 한국자동차공학회 2010 한국자동차공학회 부문종합 학술대회 Vol.2010 No.5

A design process composed of the analytical method and finite element method for the traction motor using in inwheel type electric scooter is introduced in this paper. Considering the last prevalence, an interior permanent magnet synchronous motor is studied. In this process, first, the target speed-torque characteristic of the motor is estimated depending on the desired scooter dynamic capability. And then, according to the space restriction, the initial model is proposed by using Fourier analysis method. In order to reduce the design time, a technique called EL-map is proposed and used to improve the initial model to achieve required voltage, current and efficiency. Finally, using response surface methodology, the cogging torque, torque ripple, etc. are optimized. The experiment results will be used to verify this design process.

BLDC Motor Control System using ASK DC-link PLC Technology

Tao Yu,Sung-Geun Song,Se-Min Kim,Kwang-Heon Kim,Sung-Jun Park 한국조명·전기설비학회 2009 조명·전기설비학회논문지 Vol.23 No.3

Power line communication or power line canier (PLC) is a system for carrying data on a conductor and can also used for electric power transmission. Now the powers used in the motor drive system are mostly DC sources. Even AC powers in some systems are generated from DC sources by the inverter. It is can be forecasted that the DC-link PLC technology will be widely used in various industrial fields. In this paper a novel BLDC motor control system using ASK DC-link PLC technology is proposed. The characteristic of this system is that the communication only needs 2 DC lines and there are no additional lines to translate the reference signals. The number of signal cables can be minimized when the DC-link PLC method is applied in the multi motor control system and the slip ring design also be simplified when this method is applied in rotation machines. The proposed motor control system is clarified by the PSIM and MATLAB simulations and tested through the hardware prototype.

Inactivation of Chloramphenicol and Florfenicol by a Novel Chloramphenicol Hydrolase

Tao, Weixin,Lee, Myung Hwan,Wu, Jing,Kim, Nam Hee,Kim, Jin-Cheol,Chung, Eunsook,Hwang, Eul Chul,Lee, Seon-Woo American Society for Microbiology 2012 Applied and environmental microbiology Vol.78 No.17

<B>ABSTRACT</B><P>Chloramphenicol and florfenicol are broad-spectrum antibiotics. Although the bacterial resistance mechanisms to these antibiotics have been well documented, hydrolysis of these antibiotics has not been reported in detail. This study reports the hydrolysis of these two antibiotics by a specific hydrolase that is encoded by a gene identified from a soil metagenome. Hydrolysis of chloramphenicol has been recognized in cell extracts ofEscherichia coliexpressing a chloramphenicol acetate esterase gene,<I>estDL136</I>. A hydrolysate of chloramphenicol was identified as<I>p</I>-nitrophenylserinol by liquid chromatography-mass spectroscopy and proton nuclear magnetic resonance spectroscopy. The hydrolysis of these antibiotics suggested a promiscuous amidase activity of EstDL136. When<I>estDL136</I>was expressed inE. coli, EstDL136 conferred resistance to both chloramphenicol and florfenicol onE. coli, due to their inactivation. In addition,E. colicarrying<I>estDL136</I>deactivated florfenicol faster than it deactivated chloramphenicol, suggesting that EstDL136 hydrolyzes florfenicol more efficiently than it hydrolyzes chloramphenicol. The nucleotide sequences flanking<I>estDL136</I>encode proteins such as amidohydrolase, dehydrogenase/reductase, major facilitator transporter, esterase, and oxidase. The most closely related genes are found in the bacterial familySphingomonadaceae, which contains many bioremediation-related strains. Whether the gene cluster with<I>estDL136</I>inE. coliis involved in further chloramphenicol degradation was not clear in this study. While acetyltransferases for chloramphenicol resistance and drug exporters for chloramphenicol or florfenicol resistance are often detected in numerous microbes, this is the first report of enzymatic hydrolysis of florfenicol resulting in inactivation of the antibiotic.</P>