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1%미만의 부피비를 가지는 알루미나 나노유체의 유효 열전도도
이병호(Byeong Ho Lee),김준호(Jun Ho Kim),공유찬(Yu Chan Kong),장석필(Seok Pil Jang),구자예(Ja-Ye Koo) 대한기계학회 2007 대한기계학회 춘추학술대회 Vol.2007 No.5
In this paper, effective thermal conductivities of water-based Al₂O₃-nanofluids with low concentration from 0.01 vol. % to 0.3 vol. % are experimentally obtained by transient hot wire method (THWM). The water-based Al₂O₃-nanofluids are manufactured by two-step method which is widely used. To examine suspension and dispersion characteristics of the water-based Al₂O₃-nanofluids, Zeta potential as well as transmission electron micrograph (TEM) is observed. We confirm the manufactured Al₂O₃-nanofluids have good suspension and dispersion. The effective thermal conductivities of the water-based Al₂O₃-nanofluids with low concentration are enhanced up to 1.64% compared with that of DI water at 21℃. In addition, experimental results are compared with theoretical results from Jang and Choi model.
수리조선업 근로자들의 단순흉부촬영에서 흉막 비후 유병률 : 석면 노출과 관련하여
예병진,김정일,이현재,김기남,이기남,정갑열,김준연,윤성호 大韓産業醫學會 2008 대한직업환경의학회지 Vol.20 No.1
목적: 본 연구는 수리조선업 사업장의 석면 노출 근로자와 비노출 근로자의 단순흉부촬영 검사에서 흉막 비후의 유병률 차이를 비교하고 석면 노출군의 특징을 확인하는 것을 목적으로 하였다. 방법: 한 수리조선소에 현재 근무하고 있거나 퇴직한 근로자 중 2005년부터 2007년까지 단순흉부촬영을 받았던 근로자 1,701명(79.4%)을 대상으로 석면 노출 여부와 노출기간에 따른 흉막 비후의 유병률을 분석하였다. 결과: 흉막 비후 유병률은 석면 노출군에서 5.2%,비 노출군에서 3.1%를 보였으며(p<O.05),특히 50대 이상에서 석면 노출군 17.6%,비노출군 8.7%로 큰 차이를 보였다(p<O.05). 결핵의 병력이 있거나 의심되는 근로자들을 제외한 경우에도 유병률의 유의한 차이가 있었다. 20∼29년간 석면에 노출된 경우 16.5%. 30년 이상인 경우 30.8%로 흉막 비후 유병률이 매우 높았다. 석면 노출 기간이 20∼29년, 30년 이상일 경우 흉막 비후의 교차비가 각각 2. 34(95%CI: 1.15∼4.77), 2.95(95%CI: 1.08∼8.07)이었다. 결론: 20년 이상 석면에 노출된 경우 흉막 비후 위험도가 높아지므로 적극적인 의학적 감시와 연구가 필요하다고 사료된다. Objectives: This study evaluated the prevalence of asbestos exposure-induced pleural thickening on chest radiograph in repairing shipyard workers. Methods: A total of 2,114 incumbent and retired workers in a shipyard underwent chest radiograph, questionnaire study, interview, and physical exam from 2005 to 2007. Finally, 1,702 workers were selected and classified into two groups according to asbestos exposure: exposure and non-exposure groups. The characteristics in the exposure group were investigated. Results: The prevalence of pleural thickening on chest radiograph was 5.2 % and 3.1 % in the exposure and non-exposure groups, respectively (P<0.05). In those aged 50 years or above, the prevalence was 17.6 % and 8.7 % in the exposure and non-exposure groups, respectively (P<0.05). The prevalence was 16.5 % and 30.2 % and the odds ratio was 2.34 (95% CI; 1.15-4.77) and 2.95 (95%CI; 1.08-8.07) in the workers with an exposure duration of 20-29 years and more than 30 years, respectively. The prevalence was higher when considering tuberculosis history. Conclusions: The prevalence was increased with increasing exposure duration was more than 20 years. The authors therefore suggest that this group should be followed up periodically by special program and that a longitudinal study with repairing shipyard workers as the cohort should be undertaken.
노호영 ( Ho Young Rho ),황준병 ( Jun Byeong Hwang ),차예본 ( Ye Bon Cha ),서홍석 ( Hong Seok Seo ),김충현 ( Chung Hyeon Kim ),이형우 ( Hyeong Woo Lee ),김현태 ( Hyeon Tae Kim ),전상곤 ( Sang Gon Jeon ) 한국농업정책학회 2019 농업경영정책연구 Vol.46 No.2
This paper analyses the effect of ICT technology of cow estrus detection which is necessary for Hanwoo breeding, on the number of calf-birth, market supply and demand, and farm household income. The results are as follows. The number of calf-birth increased by 2.3~11.3% after introducing ICT technology, the number of breeding heads increased by 2.8~13.8%, and the number of slaughter increased by 1.7~9.0% according to scenarios in 2025. Increased supply lowered male wholesale prices by 2.2~11.1% in 2025. Adopting new ICT technology incurred more price fall than sales increase which may lower farm income. However, considering cost decrease incurred by the new technology increases farm income by 2.7~9.8% in 2025. The adoption of smart-farm will not only increase production efficiency but also contribute to enlarge farm scale in the long term. However, there are various difficulties such as uncertainty of investment performance, difficulty for applying to small farms, and lack of standardization of smart farm devices. In particular, the government should pay attention to the industrial economic effects resulting from technology development.
AE-SOM을 이용한 EVA 생산 공정 이상 검출 및 진단
박병언 ( Byeong Eon Park ),지유미 ( Yumi Ji ),심예슬 ( Ye Seul Sim ),이규황 ( Kyu-hwang Lee ),이호경 ( Ho Kyung Lee ) 한국화학공학회 2020 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.58 No.3
In this study, the AE-SOM method, which combines auto-encoder and self-organizing map, is used to detect and diagnose faults in EVA production process. Then, the fault propagation pathways are identified using Granger causality test. One year and seven months of operation data were obtained to detect faults of the process, and the process variables of the autoclave reactor are mainly analyzed. In the data pretreatment process, the data are standardized and 200 samples of each grade are randomly chosen to obtain a fault detection model. After that, the best matching unit (BMU) of each grade is confirmed by applying AE-SOM. The faults are determined based on each BMU. When a fault is found, the most causative variable of the fault is identified by using a contribution plot, and the fault propagation pathway is identified by Granger causality test. The prognostic of the two shutdowns is detected, and the fault propagation pathway caused by the faulty variable was analyzed.
( Jun Ho Lee ),( Jae Hee Suh ),( Soo Youn Choi ),( Hyun Je Kang ),( Hwan Hee Lee ),( Byeong Jin Ye ),( Seok Won Jung ),( Chang Jae Kim ),( Whaseon Lee-kwon ),( Ji Young Park ),( Kyung Jae Myung ),( Ne 대한간학회 2017 춘·추계 학술대회 (KASL) Vol.2017 No.1
Aims: Tonicity-responsive enhancer binding protein (TonEBP) is a transcription cofactor at the promoters of inflammatory genes including TNFα and COX-2. In a mouse model of hepatocellular carcinoma (HCC), TonEBP expression is dramatically higher in the tumors compared to surrounding hepatic tissues. Experiments with genetically modified animals show that higher TonEBP expression leads to more and bigger tumors demonstrating a critical role of TonEBP in tumor initiation and development (unpublished observations). Aim of this study was to investigate the role of TonEBP in patients with HCC. Methods: A total of 296 patients who underwent hepatic resection for HCC at the Ulsan University Hospital were included in the study. All the patients were HCC treatment-naive before surgery and had a grossly complete resection. Fixed tissues were used to prepare tissue microarrays to quantify TonEBP expression. Results: TonEBP expression was higher in tumors compared to their surrounding non-tumor in 92.6% (274/296) of the patients. The median postoperative follow-up period was 31 months (range = 1-105 months). Postoperative recurrence was observed in 144 cases (48.7%). The 1-, 3-, and 5-year HCC recurrence rates were 32.7%, 51.8%, and 61.1%, respectively. Extrahepatic metastasis and death were observed in 61 (20.6%) and 84 (28.4%) of cases, respectively. Higher TonEBP expression in non-tumor and tumor was associated with tumor size, vascular invasion, and advance tumor grade. As for recurrence, multivariate analysis revealed that tumor size, microvascular and lymphovascular invasion along with higher non-tumor TonEBP expression displayed strong association. As for extrahepatic metastasis, ALT, albumin, microvascular and lymphovascular invasion along with higher non-tumor TonEBP expression displayed strong association. The presence of microvascular invasion, albumin, and higher tumor TonEBP expression were significantly associated with reduced overall survival. Conclusions: TonEBP is strong post-operative prognosticator of poor outcome including recurrence, metastasis, and death. TonEBP is an attractive candidate for biomarker of HCC and a therapeutic target.
Lee, Jun Ho,Suh, Jae Hee,Choi, Soo Youn,Kang, Hyun Je,Lee, Hwan Hee,Ye, Byeong Jin,Lee, Gap Ryol,Jung, Seok Won,Kim, Chang Jae,Lee-Kwon, Whaseon,Park, Jiyoung,Myung, Kyungjae,Park, Neung Hwa,Kwon, Hyu BMJ Publishing Group 2019 Gut: journal of the British Society of Gastroenter Vol.68 No.2
<P><B>Objectives</B></P><P>Hepatocellular carcinoma (HCC) is a common cancer with high rate of recurrence and mortality. Diverse aetiological agents and wide heterogeneity in individual tumours impede effective and personalised treatment. Tonicity-responsive enhancer-binding protein (TonEBP) is a transcriptional cofactor for the expression of proinflammatory genes. Although inflammation is intimately associated with the pathogenesis of HCC, the role of TonEBP is unknown. We aimed to identify function of TonEBP in HCC.</P><P><B>Design</B></P><P>Tumours with surrounding hepatic tissues were obtained from 296 patients with HCC who received completion resection. TonEBP expression was analysed by quantitative reverse transcription–quantitative real-time PCR (RT-PCR) and immunohfistochemical analyses of tissue microarrays. Mice with TonEBP haplodeficiency, and hepatocyte-specific and myeloid-specific TonEBP deletion were used along with HCC and hepatocyte cell lines.</P><P><B>Results</B></P><P>TonEBP expression is higher in tumours than in adjacent non-tumour tissues in 92.6% of patients with HCC regardless of aetiology associated. The TonEBP expression in tumours and adjacent non-tumour tissues predicts recurrence, metastasis and death in multivariate analyses. TonEBP drives the expression of cyclo-oxygenase-2 (COX-2) by stimulating the promoter. In mouse models of HCC, three common sites of TonEBP action in response to diverse aetiological agents leading to tumourigenesis and tumour growth were found: cell injury and inflammation, induction by oxidative stress and stimulation of the COX-2 promoter.</P><P><B>Conclusions</B></P><P>TonEBP is a key component of the common pathway in tumourigenesis and tumour progression of HCC in response to diverse aetiological insults. TonEBP is involved in multiple steps along the pathway, rendering it an attractive therapeutic target as well as a prognostic biomarker.</P>
Kim, Myung-Ho,Kim, Hee-Hoon,Jeong, Jong-Min,Shim, Young-Ri,Lee, Jun-Hee,Kim, Ye Eun,Ryu, Tom,Yang, Keungmo,Kim, Kyu-Rae,Jeon, Byeong-Min,Kim, Sun Chang,Jung, Jae-Kwang,Choi, Jae-Kap,Lee, Young-Sun,Byu The Korean Society of Ginseng 2020 Journal of Ginseng Research Vol.44 No.6
Background: Recently, beneficial roles of ginsenoside F2 (GF2), a minor constituent of Panax ginseng, have been demonstrated in diverse inflammatory diseases. However, its roles in alcoholic liver inflammation and injury have not been clearly understood. Here, we investigated the underlying mechanism by which GF2 ameliorated alcoholic liver injury. Methods: To induce alcoholic liver injury, C57BL/6J wild type (WT) or interleukin (IL)-10 knockout (KO) mice were orally administered with ethanol (3 g/kg) or ethanol-containing GF2 (50 mg/kg) for 2 wk. Liver injury and infiltration of macrophages and neutrophils were evaluated by serum biochemistry and immunohistochemistry, respectively. The changes of hepatic immune cells were assessed by flow cytometry and polymerase chain reaction analysis. In vitro differentiation of naïve T cells was performed. Results: GF2 treatment significantly attenuated alcoholic liver injury, in which infiltrations of inflammatory macrophages and neutrophils were decreased. Moreover, the frequencies of Foxp3<sup>+</sup> regulatory T cells (Tregs) increased but IL-17-producing T (Th17) cells decreased in GF2-treated mice compared to controls. Furthermore, the mRNA expression of IL-10 and Foxp3 was significantly increased, whereas IL-17 mRNA expression was suppressed in GF2-treated mice. However, these beneficial roles of GF2 were not observed in GF2-treated IL-10 KO mice, suggesting a critical role of IL-10. Similarly, GF2 treatment suppressed differentiation of naïve T cells into Th17 cells by inhibiting RORgt expression and stimulating Foxp3 expression. Conclusion: The present study suggests that GF2 treatment attenuates alcoholic liver injury by increasing IL-10 expression and Tregs and decreasing IL-17 expression and Th17 cells.