산업단지 및 일반생활 지역의 공기 중 톨루엔에 대한 개인노출 및 생체시료의 상관성 분석

이병준(Byoungjun Lee),허 정(Jung Heo),정다영(Dayoung Jung),김순신(Sunshin Kim),류현수(Hyeon-Su Ryu),최민지(Min-Ji Choi),솨이지엔페이(Jian-Fei Shuai),임성국(Sung-Guk Im),양원호(Wonho Yang) 한국환경보건학회 2017 한국환경보건학회지 Vol.43 No.4

Objectives: The purpose of this study was to assess the correlation relationship between personal exposure and urinary hippuric acid in biological monitoring for airborne toluene in an industrial complex and in general environments. Methods: Personal exposure to toluene and its metabolite, hippuric acid, in urine were simultaneously measured in occupational environments area near an industrial complex and in general environments. The study subjects were divided into three types: 137 workers who use organic solvents in the workplace, 210 residents living near a dyeing industrial complex, and 379 residents living in general environments. The toluene exposures of workers and residents were measured by a passive sampler for four days. The urine of participants was sampled when the passive samplers of personal exposure were collected. Results: The toluene and hippuric acid concentrations of workers were the highest, followed by the concentrations of residents living near a dyeing industrial complex and residents living in general environments. The coefficient of correlation between the concentrations of toluene and hippuric acid among workers was 0.749 (p<0.01) in the workplace. On the contrary, correlations between the concentrations of toluene and hippuric acid among residents living near a dyeing industrial complex and residents living in general environments were all not significant. The relationship between the concentrations of hippuric acid and toluene in three types could be described by the exponential growth model. Conclusions: This study analyzed the relationships between toluene exposure and the concentrations of hippuric acid in urine in high, middle, and low exposure environments, and could be described by the exponential growth model.

Editor’s Highlight: A Genome-wide Screening of Target Genes Against Silver Nanoparticles in Fission Yeast

Lee, Ah-Reum,Lee, Sook-Jeong,Lee, Minho,Nam, Miyoung,Lee, Sol,Choi, Jian,Lee, Hye-Jin,Kim, Dong-Uk,Hoe, Kwang-Lae ACADEMIC PRESS 2018 TOXICOLOGICAL SCIENCES Vol.161 No.1

<P><B>Abstract</B></P><P>To identify target genes against silver nanoparticles (AgNPs), we screened a genome-wide gene deletion library of 4843 fission yeast heterozygous mutants covering 96% of all protein encoding genes. A total of 33 targets were identified by a microarray and subsequent individual confirmation. The target pattern of AgNPs was more similar to those of AgNO<SUB>3</SUB> and H<SUB>2</SUB>O<SUB>2</SUB>, followed by Cd and As. The toxic effect of AgNPs on fission yeast was attributed to the intracellular uptake of AgNPs, followed by the subsequent release of Ag<SUP>+</SUP>, leading to the generation of reactive oxygen species (ROS). Next, we focused on the top 10 sensitive targets for further studies. As described previously, 7 nonessential targets were associated with detoxification of ROS, because their heterozygous mutants showed elevated ROS levels. Three novel essential targets were related to folate metabolism or cellular component organization, resulting in cell cycle arrest and no induction in the transcriptional level of antioxidant enzymes such as Sod1 and Gpx1 when 1 of the 2 copies was deleted. Intriguingly, <I>met</I>9 played a key role in combating AgNP-induced ROS generation via NADPH production and was also conserved in a human cell line.</P>

Intravenous Fluid Selection for Unruptured Intracranial Aneurysm Clipping : Balanced Crystalloid versus Normal Saline

Kang, Jian,Song, Young Joo,Jeon, Sujeong,Lee, Junghwa,Lee, Eunsook,Lee, Ju-Yeun,Lee, Euni,Bang, Jae Seung,Lee, Si Un,Han, Moon-Ku,Oh, Chang Wan,Kim, Tackeun The Korean Neurosurgical Society 2021 Journal of Korean neurosurgical society Vol.64 No.4

Objective : While balanced crystalloid (BC) could be a relevant fluid regimen with buffer system compared with normal saline (NS), there have been no studies on the optimal fluid for surgery of an unruptured intracranial aneurysm (UIA). This study aimed to compare the effects of fluid regimens between NS and BC on the metabolic and clinical outcomes of patients who underwent surgery for UIA. Methods : This study was designed as a propensity score matched retrospective comparative study and included adult patients who underwent UIA clipping. Patient groups were categorized as NS and BC groups based on the types of pre-operative fluid and the amount of fluid administered during surgery. The primary outcomes were defined as electrolyte imbalance and acidosis immediately after surgery. The secondary outcomes were the length of stay in the intensive care unit (ICU) and duration from the end of the operation to extubation. Results : A total of 586 patients were enrolled in this study, with each of 293 patients assigned to the NS and BC groups, respectively. Immediately after surgery, serum chloride levels were significantly higher in the NS group. Compared to the NS group, the BC group had lower incidence rates of acidemia (6.5% vs. 11.6%, p=0.043) and metabolic acidosis (0.7% vs. 4.4%, p=0.007). As compared to NS group, BC group had significantly shorter duration from the end of the operation to extubation (250±824 vs. 122±372 minutes, p=0.016) and length of stay in ICU (1.37±1.11 vs. 1.12±0.61 days, p=0.001). Throughout multivariable analysis, use of BC was found to be significant factor for favorable post-operative results. Conclusion : This study showed that the patients who received BC during UIA clipping had lower incidence of metabolic acidosis, earlier extubation and shorter ICU stay compared to those who received NS. Therefore, using BC as a peri-operative fluid can be recommended for patients who undergo surgery for UIA.

포스트모던 도예의 하이브리드적 유형 분석

천지엔명(Chen Jian ming),이명순(Lee Myung soon) 한국조형디자인학회 2018 조형디자인연구 Vol.21 No.3

하이브리드 기법은 20세기 이후로 포스트모던 도예에서 탈 중심지향성, 상호텍스트성, 파편화 등의 의미로 해석되던 것이 21세기에 와서는 근본적으로 서로 다른 사물들의 결합, 융합 등 그 의미상 확대와 심화가 동시에 일어나고 있다. 그 기법은 제작과정인 태토, 성형, 시유 및 소성에서 이질적인 요소들이 상호 결합해서 다양한 유형을 창출하고 있는데, 본 연구자는 그것을 네 가지로 구분, 분석하였다. 첫째 유형은 인체, 동물, 사물 간의 이종 형태들의 결합으로서 그리스, 로마 신화에서 동물 머리와 인간 신체, 혹은 동물 얼굴과 인간 다리 등의 결합이 대표적이다. 중국의『산해경』에서도 인간과 짐승의 결합형, 짐승과 짐승의 결합형 등의 반인반승을 언급했으며, 민경익, 성동훈, 권나리와 노트킨의 작품들도 논하였다. 둘째 유형은 재료 결합형 하이브리드 도예로서 고전적인 그릇의 형태와 현대적 색감의 시유, 하이브리드 몽타주 기법, 현대사회 아이콘의 차용, 성적임 등의 페미니즘, 제 예술 영역 사이의 교류와 융합, 다국적인 문화의 융합 등을 주제나 표현소재로 다루었다. 그리고 이와 관련된 신미경, 한, 윤영수, 오펜하임, 이수경, 탕의 작품을 제시, 분석하였다. 셋째 유형은 매체 결합형 하이브리드 도예로서 미디어의 활용을 통한 과학과 예술의 접목, 도자와 직조의 결합, 도예와 음악의 만남, 순수미술과 디자인의 만남 등 제 예술의 영역에서 판이한 특성을 가진 매체들의 결합이나 융합을 시도한 것이다. 그리고 이와 관련된 양민하, 이은주, 치마티의 작품을 제시, 분석하였다. 넷째 유형은 행위 예술형 하이브리드 도예로서 작품의 제작과정 중에서 특히 성형이나 시유과정을 순수미술의 입장에서나 아니면 사회문화적 현상을 융합하여 클로즈업시키는 등의 콘텐츠를 작가가 행위예술로 시연하고, 거기에 음악 등 다른 예술 영역을 가미함으로써 색다른 융합으로서의 하이브리드 기법을 선보였다. 그리고 이와 관련된 이강효, 맥크라켄, 호울레, 브라운스워드, 케리트 랭리쉬-스미스의 작품을 제시, 분석하였다. Hybrid, from the 21st century, became to be interpreted as being meant of de-centeredness, inter-textuality, fragmentarizaton, etc., and simultaneously brought about the expansion and deepening in their significance like a fundamental combination, integrity, etc. of mutually different objects. Its technique of this kind creates various types by dint of a mutual combination of different elements of Postmodern ceramics in their making processes, that is, clay, formation, glazing, and firing, which I divided it into four, and analyzed them. First type is related with a combination of hybridization among man, animal, and object, frequently appearing as examples combining animal’s head with man’s body, or animal’s face with man’s legs, etc. as in Greek, Rome mythology. There are also several examples from Shan Hai Jing containing many Chinese myths, indicating a semi-animal or a semi-man type, a combined form of man with animal, of animal with animal, etc. Additionally, I attempted to prove it with the artworks by Min Gyeong-ik, Seong Dong-hoon, Kwon Na-ri and R. Notkin. Second type is a material-combined type of hybrid ceramics, and I treated the form of classical vessels and glazing of modern colors, hybrid montage technique, borrowing of icons of contemporary society, Feminism of sexuality, exchange and integrity between the disciplines, integrity of multinational cultures as theme or subject-matters. And I suggested and analyzed the ceramics by Shin Mi-kyung, D. Han, Yoon Young-soo, M. Oppenheim, Lee Su-kyung, and B. L. S. Tang. Third type is a medium-combined type of hybrid ceramics, and I analyzed the artworks that proceeded to a combination or integrity of media with different characters in the field of art genre such as an implantation of science with art, a unification of ceramic art with weaving, a meeting of ceramics with music, an encounter of fine art with design, etc. through the usage of the media. And I suggested and analyzed the ceramics by Yang Min-ha, Lee Eun-ju, and A. Cimatti. Fourth type is a performance-typed hybrid ceramics, and the artists displayed the contents to close-up the formation or glazing especially among the making processes of ceramics either from the standpoint of fine art or from a combination with sociocultural phenomenon, to which they represented a hybrid technique as a unique integrity by adding other art genre such as music, etc. I suggested and analyzed the ceramics by Lee Kang-hyo, J. J. McCraken, N. Hole, N. Brownsword, and Kate Langrish-Smith.

A basic study on the thermal analysis of 45,000-rpm spindle with different preload

Jian lee(이건),Dong Hyeon Kim(김동현),Choon Man Lee(이춘만) 한국정밀공학회 2013 한국정밀공학회 학술발표대회 논문집 Vol.2013 No.5월

Improvement of DITC SRM with a Novel 4-level Converter

Jianing Liang,이진국(Zhen-Guo Lee),이동희(Dong-Hee Lee),안진우(Jin-Woo Ahn) 대한전기학회 2006 대한전기학회 학술대회 논문집 Vol.2006 No.7

This paper presents a direct instantaneous torque control (DITC) of Switched Reluctance Motor (SRM) with a novel 4-1evel converter to obtain smooth torque and dynamic performance improvement. The DITC method can reduce the high inherent torque ripple of SRM drive system, but driving efficiency and dynamic performance are somewhat low due to the slow excitation current build-up. Since the 4-level converter can obtain a addition high voltage to get fast excitation current and demagnetization current, so, it can improve dynamic performance easily. As a high performance SRM drive system with low torque ripple and high dynamic performance can be implemented. The validity of proposed method is verified by some computer simulations and comparative experiments.

Traf4 is required for tight junction complex during mouse blastocyst formation

Jian Lee,Inchul Choi 한국동물생명공학회(구 한국동물번식학회) 2021 Journal of Animal Reproduction and Biotechnology Vol.36 No.4

Traf4 (Tumor necrosis factor Receptor Associated Factor 4) is a member of the tumor necrosis factor receptor (TNFR) - associated factors (TRAFs) family. TRAF4 is overexpressed in tumor cells such as breast cancer and associated with cytoskeleton and membrane fraction. Interestingly, TRAF4 was localized with tight junctions (TJs) proteins including OCLN and TJP1 in mammary epithelial cells. However, the expression patterns and biological function of Traf4 were not examined in preimplantation mouse embryos although Traf4-deficient mouse showed embryonic lethality or various dramatic malformation. In this study, we examined the temporal and spatial expression patterns of mouse Traf4 during preimplantation development by qRT-PCR and immunostaining, and its biological function by using siRNA injection. We found upregulation of Traf4 from the 8-cell stage onwards and apical region of cell – cell contact sites at morula and blastocyst embryos. Moreover, Traf4 knockdown led to defective TJs without alteration of genes associated with TJ assembly but elevated p21 expression at the KD morula. Taken together, Traf4 is required for TJs assembly and cell proliferation during morula to blastocyst transition.

DITC of SRM using 4-Level Converter

Jianing Liang,Zhen-Guo Lee(이진국),Dong-Hee Lee(이동희),Jin-Woo Ahn(안진우) 대한전기학회 2006 대한전기학회 학술대회 논문집 Vol.2006 No.4

This paper proposes a DITC(Direct Instantaneous Torque Control) of SRM (Switched Reluctance Motor) using a novel 4-level converter for smooth torque control and high efficiency. DITC of SRM is very useful for smooth torque control, but the driving efficiency is low due to advanced current that does not produce torque. For the high efficiency control of SRM, fast excitation and demagnetization of phase current are required. A novel 4-level converter and a new control scheme are present to improve the driving efficiency. The proposed DITC of SRM using 4-1evel converter is verified by computer simulation.

Single-Phase SRM Drive With Torque Ripple Reduction and Power Factor Correction

Lee Dong-Hee,Lee Zhen-Guo,Liang Jianing,Ahn Jin-Woo IEEE 2007 IEEE transactions on industry applications Vol.43 No.6

<P>In a single-phase switched reluctance motor (SRM) drive, the dc voltage source is generally supplied by a circuit consisting of a bridge rectifier and a filter capacitor connected to an ac line. The charging time of the capacitor is shorter from the ac source as capacity increases. The bridge rectifier draws pulsating current from the ac source, which results in a degraded power factor (PF) and lower system efficiency. A single-phase SRM drive system is presented in this paper, which includes the realization of a drive circuit for the reduction of torque ripple and PF improvement with a novel switching topology. The proposed drive circuit adds one switch and one diode, which can separate the output of the ac/dc rectifier from the large capacitor and supply power to the SRM alternately. This allows the drive system to realize torque ripple reduction and PF improvement through the switching scheme. The validity of the proposed method is analyzed by mathematical modeling and tested by simulations and experiments.</P>

Paternal work stress and prolonged time to pregnancy.

Lee, Mi-Sun,Paek, Domyung,Eum, Ki-Do,Siegrist, Johannes,Li, Jian,Lee, Hye-Eun,Cho, Sung-Il Springer-Verlag 2009 INTERNATIONAL ARCHIVES OF OCCUPATIONAL AND ENVIRON Vol.82 No.2

<P>The aim of this study was to explore an association between psychosocial stress at work in married men and their spouses' prolonged time to pregnancy (TTP).</P>