Multimedia distributions, bioaccumulation, and trophic transfer of microcystins in the Geum River Estuary, Korea: Application of compound-specific isotope analysis of amino acids

Kim, Dokyun,Hong, Seongjin,Choi, Hyuntae,Choi, Bohyung,Kim, Jaeseong,Khim, Jong Seong,Park, Hodong,Shin, Kyung-Hoon Elsevier 2019 Environment international Vol.133 No.2

<P><B>Abstract</B></P> <P>To determine distributions, bioaccumulation, and trophic transfer of freshwater cyanobacterial toxins such as microcystins (MCs), surface water, suspended solids, sediments, and coastal organisms were collected from seven stations in inner and outer regions of the estuary dam in the Geum River Estuary in June and July 2017. Concentrations of MC variants (MC-LR, -RR, and -YR) in the multimedia samples were analyzed using a HPLC-MS/MS. Trophic position (TP) of organisms (fish, bivalve, gastropod, decapod, and polychaete) was determined by nitrogen stable isotope analyses of both bulk tissues and amino acids. From July to August 2017, great concentrations of MCs were detected in discharged freshwater ranging from 0.4 to 75 μg L<SUP>−1</SUP>. Considerable amounts of MCs are delivered to the Geum River Estuary in summer season. MCs spread far away as dissolved phases (18.7–49.5 ng L<SUP>−1</SUP>) in July when large amount of freshwater was discharged during the rainy season. Concentrations of MCs in marine organisms varied among species, ranging from 40 to 870 ng g<SUP>−1</SUP> dw. Bioaccumulated MCs tend to decrease with increasing TP of organisms, suggesting that MCs are biodiluted through the marine food web. Compound-specific isotope analysis (nitrogen of amino acids) provides more reliable TPs compared with those by bulk isotope analysis in a closed estuary (such as the Geum River Estuary) with large fluctuations in the isotope ratio of primary producers.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Great concentrations of MCs are detected in discharged freshwater via the estuary dam. </LI> <LI> The MCs well dissolve in water when they entered the coastal ecosystem. </LI> <LI> MC-LR is the most abundant among three MCs variants in coastal organisms. </LI> <LI> Bioaccumulated MCs decrease with increasing trophic positions of organisms. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Albumin nanoparticles with synergistic antitumor efficacy against metastatic lung cancers

Kim, Bomi,Seo, Bohyung,Park, Sanghyun,Lee, Changkyu,Kim, Jong Oh,Oh, Kyung Taek,Lee, Eun Seong,Choi, Han-Gon,Youn, Yu Seok Elsevier 2017 Colloids and surfaces Biointerfaces Vol.158 No.-

<P><B>Abstract</B></P> <P>Albumin nanoparticles are well-known as effective drug carriers used to deliver hydrophobic chemotherapeutic agents. Albumin nanoparticles encapsulating curcumin and doxorubicin were fabricated using slightly modified nanoparticle albumin-bound (nab™) technology, and the synergistic effects of these two drugs were examined. Albumin nanoparticles encapsulating curcumin, doxorubicin, and both curcumin and doxorubicin were prepared using a high pressure homogenizer. The sizes of albumin nanoparticles were ∼130nm, which was considered to be suitable for the EPR (enhanced permeability and retention) effect. Albumin nanoparticles gradually released drugs over a period of 24h without burst effect. To confirm the synergistic effect of two drugs, <I>in vitro</I> cytotoxicity assay was performed using B16F10 melanoma cells. The cytotoxic effect on B16F10 melanoma cells was highest when co-treated with both curcumin and doxorubicin compared to single treatment of either curcumin and doxorubicin. The combined index calculated by medium-effect equation was 0.6069, indicating a synergistic effect. Results of confocal laser scanning microscopy and fluorescence-activated cell sorting corresponded to results from an <I>in vitro</I> cytotoxicity assay, indicating synergistic cytotoxicity induced by both drugs. A C57BL/6 mouse model induced by B16F10 lung metastasis was used to study <I>in vivo</I> therapeutic effects. When curcumin and doxorubicin were simultaneously treated, the metastatic melanoma mass in the lungs macroscopically decreased compared to curcumin or doxorubicin alone. Albumin nanoparticles encapsulating two anticancer drugs were shown to have an effective therapeutic result and would be an excellent way to treat resistant lung cancers.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We developed curcumin and doxorubicin co-loaded albumin nanoparticles. </LI> <LI> The nanoparticles were fabricated by high pressure homogenization <I>via</I> Nab<SUP>®</SUP> technique. </LI> <LI> The nanoparticles exhibited synergistic cytotoxicity on the B16F10 cells. </LI> <LI> These new albumin nanoparticles would be potential as a treatment for metastatic lung cancers. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

자동차 튜닝을 위한 엔진 ECU 맵핑 기술교육

김보형(Bohyung Kim),이상열(Sangryol Lee) 한국자동차공학회 2008 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

The higher automobile control devices was developed with the development of industrial technology. Especially, CAN NETWORK has accelerated automobile systems in recent years. In this papers, the new technology automobile is focused with user's demands according to car tuning trend. The main parts of new car are evaluated for automobile tuning, namely, ECU maping technology. Already this new technology are progressing and grafting for high valued technology in the European countries.

Inter-laboratory Comparison of Stable Carbon and Nitrogen Isotopic Composition Data Using Elemental Analyzer-isotope Ratio Mass Spectrometers

( Jung-hyun Kim ),( Sujin Kang ),( Yeon-sik Bong ),( Kwangkyu Park ),( Tae-woo Kang ),( Yong-se Park ),( Dahae Kim ),( Seunghyun Choi ),( Young Ji Joo ),( Bohyung Choi ),( Seung-il Nam ),( Sang-mo Lee 한국환경분석학회 2018 환경분석과 독성보건 Vol.21 No.4

In this study, inter-laboratory comparison was done using elemental analyzer-isotope ratio mass spectrometers (EA-IRMSs) to determine carbon and nitrogen contents as well as stable carbon and nitrogen isotopic compositions (δ ¹³C and δ ¹⁵N) of five environmental samples containing lake and marine sediments, higher plant leaves, and fish muscle, and one organic analytical standard (Protein (Casein) Standard OAS). Five national laboratories participated in this comparison study, and each laboratory analyzed all five samples and the analytical standard. Results showed that variations in total organic carbon (TOC) and total nitrogen (TN) contents as well as δ ¹³CTOC and δ ¹⁵NTN values among the laboratories were large compared to the analytical uncertainties. The results highlighted the inhomogeneity of the test samples and thus, the need to select suitable standard reference materials for future inter-laboratory studies. Further inter-laboratory comparison exercises could promote good measurement practices in the acquisition of stable carbon and nitrogen isotopic composition data.

Contribution of petroleum-derived organic carbon to sedimentary organic carbon pool in the eastern Yellow Sea (the northwestern Pacific)

Kim, Jung-Hyun,Lee, Dong-Hun,Yoon, Suk-Hee,Jeong, Kap-Sik,Choi, Bohyung,Shin, Kyung-Hoon Elsevier 2017 CHEMOSPHERE - Vol.168 No.-

<P><B>Abstract</B></P> <P>We investigated molecular distributions and stable carbon isotopic compositions (δ<SUP>13</SUP>C) of sedimentary <I>n</I>-alkanes (C<SUB>15</SUB> C<SUB>35</SUB>) in the riverbank and marine surface sediments to trace natural and anthropogenic organic carbon (OC) sources in the eastern Yellow Sea which is a river dominated marginal sea. Molecular distributions of <I>n</I>-alkanes are overall dominated by odd-carbon-numbered high molecular weight <I>n</I>-C<SUB>27</SUB>, <I>n</I>-C<SUB>29</SUB>, and <I>n</I>-C<SUB>31</SUB>. The δ<SUP>13</SUP>C signatures of <I>n</I>-C<SUB>27</SUB>, <I>n</I>-C<SUB>29</SUB>, and <I>n</I>-C<SUB>31</SUB> indicate a large contribution of C<SUB>3</SUB> gymnosperms as the main source of <I>n</I>-alkanes, with the values of −29.5 ± 1.3‰, −30.3 ± 2.0‰, and −30.0 ± 1.7‰, respectively. However, the contribution of thermally matured petroleum-derived OC to the sedimentary OC pool is also evident, especially in the southern part of the study area as shown by the low carbon preference index (CPI<SUB>25-33</SUB>, <1) and natural <I>n</I>-alkanes ratio (NAR, <−0.6) values. Notably, the even-carbon-numbered long-chain <I>n</I>-C<SUB>28</SUB> and <I>n</I>-C<SUB>30</SUB> in this area have higher δ<SUP>13</SUP>C values (−26.2 ± 1.5‰ and −26.5 ± 1.9‰, respectively) than the odd-carbon-numbered long-chain <I>n</I>-C<SUB>29</SUB> and <I>n</I>-C<SUB>31</SUB> (−28.4 ± 2.7‰ and −28.4 ± 2.4‰, respectively), confirming two different sources of long-chain <I>n</I>-alkanes. Hence, our results highlight a possible influence of petroleum-induced OC on benthic food webs in this ecosystem. However, the relative proportions of the natural and petroleum-derived OC sources are not calculated due to the lack of biogeochemical end-member data in the study area. Hence, more works are needed to constrain the end-member values of the organic material supplied from the rivers to the eastern Yellow Sea and thus to better understand the source and depositional process of sedimentary OC in the eastern Yellow Sea.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The contribution of C<SUB>3</SUB> gymnosperms is the main source of <I>n</I>-alkanes in the eastern Yellow Sea. </LI> <LI> The contribution of petroleum-derived OC to the sedimentary OC pool is evident in the southern part of the study area. </LI> <LI> Our results indicate a possible influence of petroleum-induced OC on benthic food webs in this ecosystem. </LI> </UL> </P>

SOC/Capacity Estimation of a Li-Ion Battery based on Pattern Recognition at Different Temperature

Jonghoon Kim,Seongjun Lee,Bohyung Cho 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

Differences in electrochemical characteristics among Li-Ion batteries caused by temperature effect result in erroneous state-of-charge (SOC)/capacity estimations when using the existing dual extended Kalman filter (DEKF) algorithm is used. Therefore, this study presents an application of the DEKF based on pattern recognition combined with empirical parameters measurement for high accuracy SOC/capacity estimations at various temperatures. The averaged 9 discharging/charging voltage-temperature (DCVT) patterns for 10 fresh Li-Ion batteries at experimental temperatures are measured as representative patterns, together with battery model parameters such as capacity, open circuit voltage (OCV), and two resistances (Ri, RDiff). Through statistical analysis, the Hamming network is applied for identification of the representative pattern that matches most closely of the pattern of the arbitrary battery to be measured at any temperature. Based on temperature-checking process, model parameters for representative DCVT pattern can be then applied to estimate SOC/capacity of an arbitrary battery using the DEKF. This avoids the need for repeated parameter measurement.

Small gold nanorods-loaded hybrid albumin nanoparticles with high photothermal efficacy for tumor ablation

Seo, Bohyung,Lim, Kyungseop,Kim, Sung Soo,Oh, Kyung Taek,Lee, Eun Seong,Choi, Han-Gon,Shin, Beom Soo,Youn, Yu Seok Elsevier 2019 Colloids and surfaces Biointerfaces Vol.179 No.-

<P><B>Abstract</B></P> <P>Photothermal therapy using gold nanorods (AuNRs) has gained great attention for cancer therapy because AuNRs emit heat and induce tumor cell death responding to the near infrared light. However, the anticancer efficiency of AuNRs alone is undermined by its poor in vivo stability and potential toxicity. The prime purpose of this study was to send more AuNRs into tumors to more fully ablate them. For this, we fabricated hybrid albumin nanoparticles encapsulating small AuNRs (AuNRs-Alb-NPs), which take advantage of biocompatible albumin as a carrier, with better tumor targetability and high in vivo photothermal activity. The sizes of length/width of AuNRs were approximately 20.5 nm and 4.6 nm, respectively, showing a 4.5 aspect ratio, and the size of the resulting AuNRs-Alb-NPs was ˜130 nm, all of which are favorable for glomerular filtration and passive tumor targeting via extravasation. We chose the best formulation for AuNRs-Alb-NPs by in vitro cytotoxicity based on photothermal conversion efficiency considering the incorporated number of AuNRs. Visualized by a photothermal camera, the local tumor temperature of mice treated with AuNRs-Alb-NPs increased to 57℃, which was sufficient for the hyperthermal effect with 808 nm laser irradiation. Subsequently, AuNRs-Alb-NPs displayed remarkably better tumor ablation vs. naïve formulation of AuNRs (tumor volume: 73.8 ± 105.8 vs. 1455.3 ± 310.4 mm<SUP>3</SUP> at day 8) in the glioblastoma N2a tumor-bearing mice. Most of all, we demonstrated, using photoacoustic imaging and inductively coupled plasma mass spectrometry, that this much better tumor ablation was due to enhanced tumor targeting with albumin nanoparticles. We believe our AuNRs-Alb-NPs should be considered promising photothermal agents that are safer, have good targetability, and exhibit excellent tumor ablation.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We developed a prototype of small gold nanorods-loaded albumin nanoparticles. </LI> <LI> The nanoparticles exhibited noticeable cytotoxicity on the glioblastoma N2a cells. </LI> <LI> The nanoparticles were much more potent in killing N2a tumors in vivo versus naïve gold nanorods. </LI> <LI> The hybrid albumin nanoparticles would be a potential photothermal agent for treating brain cancer. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Discharging/Charging Voltage-Temperature Pattern Recognition for Improved SOC/Capacity Estimation and SOH Prediction at Various Temperatures

Jonghoon Kim,Seongjun Lee,Bohyung Cho 전력전자학회 2012 JOURNAL OF POWER ELECTRONICS Vol.12 No.1

This study investigates an application of the Hamming network-dual extended Kalman filter (DEKF) based on pattern recognition for high accuracy state-of-charge (SOC)/capacity estimation and state-of-health (SOH) prediction at various temperatures. The averaged nine discharging/charging voltage-temperature (DCVT) patterns for ten fresh Li-Ion cells at experimental temperatures are measured as representative patterns, together with cell model parameters. Through statistical analysis, the Hamming network is applied to identify the representative pattern that matches most closely with the pattern of an arbitrary cell measured at any temperature. Based on temperature-checking process, model parameters for a representative DCVT pattern can then be applied to estimate SOC/capacity and to predict SOH of an arbitrary cell using the DEKF. This avoids the need for repeated parameter measuremet.

평안도 다리굿의 특성과 위상

이보형(Lee, Bohyung),김헌선(Kim, Heonseon) 한국무속학회 2014 한국무속학 Vol.0 No.29

이 연구는 평안도 다리굿을 중심에 두고 평안도 굿과 무속의 특징을 전반적으로 해명하려는 목적에서 마련되었다. 평안도 무속이나 굿 연구가 진척되었음에도 불구하고 일정한 특징이나 위상이 아직 규명되지 못한 바 있다. 지역적 특색과 의미를 정리하면서 특히 음악적 특징과 함께 지역적 특성을 중심으로 논의를 진행하였다. 그 결과 우리는 몇 가지를 정리할 수 있었다. 평안도 지역의 무속은 강신무권과 세습무권의 구분 가운데 강신무권의 전통을 지니고 있는 핵심적 권역 가운데 하나이다. 이 권역은 평안도, 황해도, 경기도 북부와 서울 등지까지 이르는 넓은 분포를 보이는데 그 중심에 평안도의 서북형 무당이 핵심을 차지하고 있다. 평안도 지역의 굿은 음악적으로 본다면 경서토리의 중심에 해당한다. 경서토리를 중심으로 본다면 이 지역의 토리가 수심가토리라는 넓은 분포를 핵심으로 하고 있다. 장단의 측면에서는 특별하게 몇 가지 긴요한 장단이 쓰이게 되는데 푸념장단, 청배장단, 앉은 청배장단, 당울림장단, 염불장단, 잦은염불장단, 감응장단, 방애장단, 돈실러가는장단, 덕담장단, 비나수장단, 절장단, 춤장단 등이 이에 해당한다고 밝혔다. This research aimed at generally explaining the characteristic of Pyongan-do gut and shamanism focusing on Pyongan-do Darigut. Nevertheless researches on Pyongan-do shamanism and gut have been progressed, regular characteristic or status have not yet been investigated. This research progressed the discussion focusing on regional characteristic along with musical characteristic, particularly, while arranging regional characteristic and meaning. As the result, this research could arrange some points as follows. Shamanism of Pyongan-do is one of core sphere which has the tradition of Gangshinmu-gwon, among the division between Gangshinmu-gwon and Seseupmu-gwon. This sphere shows a wide distribution covering Pyongan-do, Hwanghae-do, Gyeonggi-do north region, and Seoul, in the center part, northwest type shaman of Pyongan-do lies at the heart. Gut of Pyongan-do is relevant to the core of Gyeongseo-tori, in respect of musical aspect. When focusing on Gyeongseo-tori, tori of this region takes the core of sooshimga-tori, a wide distribution. In the aspect of rhythm, particularly some important rhythms are used, according to this research, they are Punyum jangdan, Cheongbae jangdan, Anjeun Cheongbae jangdan, Dangwoolrim jangdan, Yeombul jangdan, Jajeun Yeombul jangdan, Gameung jangdan, Bangae jangdan, Donsilreoganeun jangdan, Deokdam jangdan, Binasu jangdan, Jeol jangdan, Choom jangdan, etc.

설명 문장 생성을 통한 해석 가능한 시각적 질의응답 모델 분석

김단일(Danil Kim),한보형(Bohyung Han) 한국컴퓨터정보학회 2020 한국컴퓨터정보학회 학술발표논문집 Vol.28 No.2

본 연구에서는 설명 문장 생성을 통한 해석 가능한 시각적 질의응답 모델을 설계하고 학습 방법을 제시한다. 설명 문장은 시각적 질의응답 모델이 응답을 예측하는 데에 필요한 이미지 및 질문 정보와 적절한 논리적인 정보의 조합 및 정답 추론 과정이 함의되어 있을 것으로 기대한다. 설명 문장 생성 과정이 포함된 시각적 질의응답의 기본적인 모델을 기반으로 여러 가지 학습방법을 통해 설명 문장 생성 과정과 응답 예측 과정간의 상호관계를 분석한다. 이러한 상호작용을 적극적으로 활용할 수 있는 보다 개선 시각적 질의응답 모델을 제안한다. 또한 학습한 결과를 바탕으로 설명 문장의 특성을 활용하여 시각적 질의응답 추론 과정을 개선함으로써 시각적 질의응답 모델의 발전 방향을 논의한다. 본 실험을 통해서 응답 예측에 적절한 설명 문장을 제시하는 해석 가능한 시각적 질의응답 모델을 제공한다.