• Korean Chemical Engineering Research
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• 제61권4호
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• pp.523-541
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• 2023

3D 프린터의 활용이 높아짐에 따라 발생하는 화학물질에 대한 노출 빈도가 증가하고 있다. 그러나 3D 프린팅 발생 화학물질의 독성 및 유해성에 대한 연구는 미비하며, 분자 구조 데이터의 결측치로 인해 in silico 기법을 사용한 독성예측 연구는 저조한 실정이다. 본 연구에서는 화학물질의 분자구조 정보를 나타내는 주요 분자표현자의 결측치를 보간하여 3D 프린팅의 독성 및 유해성을 예측한 Data-centric QSAR 모델을 개발하였다. 먼저 MissForest 알고리즘을 사용해 3D 프린팅으로 발생되는 유해물질의 분자표현자 결측치를 보완하였으며, 서로 다른 4가지 기계학습 모델(결정트리, 랜덤포레스트, XGBoost, SVM)을 기반으로 Data-centric QSAR 모델을 개발하여 생물 농축 계수(Log BCF)와 옥탄올-공기분배계수(Log Koa), 분배계수(Log P)를 예측하였다. 또한, 설명 가능한 인공지능(XAI) 방법론 중 TreeSHAP (SHapley Additive exPlanations) 기법을 활용하여 Data-centric QSAR 모델의 신뢰성을 입증하였다. MissForest 알고리즘 기반 결측지 보간 기법은, 기존 분자구조 데이터에 비하여 약 2.5배 많은 분자구조 데이터를 확보할 수 있었다. 이를 바탕으로 개발된 Data-centric QSAR 모델의 성능은 Log BCF, Log Koa와 Log P를 각각 73%, 76%, 92% 의 예측 성능으로 예측할 수 있었다. 마지막으로 Tree-SHAP 분석결과 개발된 Data-centric QSAR 모델은 각 독성치와 물리적으로 상관성이 높은 분자표현자를 통하여 선택함을 설명할 수 있었고 독성 정보에 대한 높은 예측 성능을 확보할 수 있었다. 본 연구에서 개발한 방법론은 다른 프린팅 소재나 화학공정, 그리고 반도체/디스플레이 공정에서 발생 가능한 오염물질의 독성 및 인체 위해성 평가에 활용될 수 있을 것으로 사료된다.

• 농업생명과학연구
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• 제44권2호
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• pp.17-28
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• 2010

본 연구에서는 2000년부터 2008년 사이에 출생한 Duroc종, Landrace종 및 Yorkshire종의 GGP (Great Grand Parents) 종돈 31,455두의 농장검정자료를 이용하여 단변량 모체효과 모형에 의한 돼지의 경제형질에 대한 유전모수 및 유전력 추정을 통해 모체효과가 돼지의 경제형질에 미치는 영향에 대하여 알아보았다. 조사된 모든 형질에서 각 요인에 대한 유의성을 검정한 결과 모든 형질에 있어서 품종, 성, 출생년도, 출생계절 및 산차의 효과는 고도의 유의성이 인정되었고 (p<0.01), 모체효과 모형을 이용하였을 때 각 품종별 형질에 대해 추정된 상가적 유전 분산과 모체 유전 분산사이에 부 (-)의 공분산이 존재하고, 이들의 유전 상관도 대부분 강한 부 (-)의 상관관계를 보여 품종, 형질 및 개량 방향에 따라 모체 효과뿐만 아니라 상가적 효과와 모체 효과간의 상관관계도 적절히 고려한다면 좀 더 효율적인 개량효과를 거둘 수 있을 것으로 사료된다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권12호
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• pp.7243-7249
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• 2013

Numerous studies have been conducted regarding association between TNF-${\alpha}$ and oral cancer risk, but the results remain controversial. The present meta-analysis is performed to acquire a more precise estimation of relationships. Databases of Pubmed, the Cochrane library and the China National Knowledge Internet (CNKI) were retrieved until August 10, 2013. Pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated with fixed- or random-effect models. The heterogeneity assumption was assessed by I-squared test. Among the eight included case-control studies, all were focused on TNF-${\alpha}$-308G>A and four also concerned the TNF-${\alpha}$-238G>A polymorphism. It was found that oral cancer risk were significant decreased with the TNF-${\alpha}$-308G>A polymorphism in the additive genetic model (GG vs. AA, OR=0.19, 95% CI: [0.04, 1.00], P=0.05, I2=68.9%) and the dominant genetic model (GG+GA vs. AA, OR=0.22, 95% CI: [0.06, 0.82], P=0.03, I2=52.4%); however, no significant association was observed in allele contrast (G vs. A, OR=0.70, 95% CI: [0.23, 2.16], P=0.54, I2=95.9%) and recessive genetic models (GG vs. GA+AA, OR=0.72, 95% CI: [0.33, 1.57], P=0.41, I2=93.1%). For the TNF-${\alpha}$-238G>A polymorphism, significant associations with oral cancer risk were found in the allele contrast (G vs. A, OR=2.75, 95% CI: [1.25, 6.04], P=0.01, I2=0.0%) and recessive genetic models (GG vs. GA+AA, OR=2.23, 95%CI: [1.18, 4.23], P=0.01, I2=0.0%). Conclusively, this meta-analysis indicates that TNF-${\alpha}$ polymorphisms may contribute to the risk of oral cancer. Allele G and the GG+GA genotype of TNF-${\alpha}$-308G>A may decrease the risk of oral cancer, while allele G and the GG genotype of TNF-${\alpha}$-238G>A may cause an increase.

• Journal of Microbiology and Biotechnology
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• 제28권2호
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• pp.218-226
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• 2018

Nanometric Lactobacillus plantarum nF1 (nLp-nF1) is a biogenics consisting of dead L. plantarum cells pretreated with heat and a nanodispersion process. In this study, we investigated the immune-enhancing effects of nLp-nF1 in vivo and in vitro. To evaluate the immunostimulatory effects of nLp-nF1, mice immunosuppressed by cyclophosphamide (CPP) treatment were administered with nLp-nF1. As expected, CPP restricted the immune response of mice, whereas oral administration of nLp-nF1 significantly increased the total IgG in the serum, and cytokine production (interleukin-12 (IL-12) and tumor necrosis factor alpha (TNF-${\alpha}$)) in bone marrow cells. Furthermore, nLp-nF1 enhanced the production of splenic cytokines such as IL-12, TNF-${\alpha}$, and interferon gamma (IFN-${\gamma}$). In vitro, nLp-nF1 stimulated the immune response by enhancing the production of cytokines such as IL-12, TNF-${\alpha}$, and IFN-${\gamma}$. Moreover, nLp-nF1 given a food additive enhanced the immune responses when combined with various food materials in vitro. These results suggest that nLp-nF1 could be used to strengthen the immune system and recover normal immunity in people with a weak immune system, such as children, the elderly, and patients.

• 한국축산식품학회지
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• 제31권5호
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• pp.719-726
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• 2011

Pediococcus pentosaceus JWS 939 (JWS 939) is a nonpathogenic bacteriocin-producing probiotic isolated from the duck intestine. This study assessed the immunomodulatory effects of JWS 939 and compared them with those of Lactobacillus rhamnosus GG (LGG), a well-known immune enhancer. The immune-enhancing effects of JWS 939 were measured by measuring the production of nitric oxide (NO) and cytokines in C57BL/6 mouse peritoneal macrophages. In addition, to assess the immune enhancement abilities of JWS 939, in vivo, a Listeria monocytogenes challenge mice model was used. The results showed that heat-killed JWS 939 induced more NO and interleukin (IL)-$1{\beta}$ production in mouse peritoneal macrophages than in LGG, and that oral administration of viable JWS 939 in mice increased more NO, IL-$1{\beta}$, and tumor necrosis factor (TNF)-${\alpha}$ level than in LGG in serum upon L. monocytogenes challenge. In addition, mice fed with JWS 939 had a longer survival time after lethal challenge with L. monocytogenes, and these effects were stronger than those induced by LGG. Collectively, P. pentosaceus JWS 939 is a remarkable strain that, by releasing bacteriocin and enhancing host immune responses, may have potential as a duck feed additive to suppress pathogens.

• 대한안전경영과학회지
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• 제15권1호
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• pp.109-120
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• 2013

As information-oriented industry has been developed and electronic devices has come to be smaller, lighter, multifunctional, and high speed, the components used to the devices need to be much high density and should have find pattern due to high integration. Also, diverse reliability problems happen as user environment is getting harsher. For this reasons, establishing and securing products and components reliability comes to key factor in company's competitiveness. It makes accelerated test important to check product reliability in fast way. Out of fine pattern failure modes, failure of Electrochemical Migration(ECM) is kind of degradation of insulation resistance by electro-chemical reaction, which it comes to be accelerated by biased voltage in high temperature and high humidity environment. In this thesis, the accelerated life test for failure caused by ECM on fine pattern substrate, $20/20{\mu}m$ pattern width/space applied by Semi Additive Process, was performed, and through this test, the investigation of failure mechanism and the life-time prediction evaluation under actual user environment was implemented. The result of accelerated test has been compared and estimated with life distribution and life stress relatively by using Minitab software and its acceleration rate was also tested. Through estimated weibull distribution, B10 life has been estimated under 95% confidence level of failure data happened in each test conditions. And the life in actual usage environment has been predicted by using generalized Eyring model considering temperature and humidity by developing Arrhenius reaction rate theory, and acceleration factors by test conditions have been calculated.

• Journal of Preventive Medicine and Public Health
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• 제39권1호
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• pp.81-86
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• 2006

Background: A number of studies have reported associations between the ambient air pollution concentrations and various health outcomes. Especially, ozone is well known for primary risk factor of asthma attacks. The results of a recent study indicate that the size of the effect on health outcomes due to air pollution varied according to several conditions, including age, gender, race and the socioeconomic status. Therefore, this study was conducted to examine the associations of ozone with the childhood asthma hospitalizations as stratified by the socioeconomic status (SES) at the community level in Seoul, Korea, 2002. Methods: SES at aggregated levels was measured on the basis of average regional health-insurance rate per citizen in the area. We applied the generalized additive model to analyze the effect of ozone on asthma after controlling for the potential confounding variables that were capable of influencing the results. Results: Our analysis showed that the number of children who were hospitalized for asthma increased as the SES of the residence area decreased. The estimated relative risks of hospitalization for asthma, as stratified by the SES of the community level, were 1.12 (95% confidence interval 1.00-1.25) in districts with the highest SES levels, 1.24 (95% CI=1.08-1.43) within the moderate SES levels, and 1.32 (95% CI=1.11-1.58) in the districts with the lowest SES levels. Conclusions: Our analysis showed that exposure to air pollution did not equally affect the health status of individuals. This suggests that not only the biological-sensitivity markers, but also the SES of the subjects should be considered as potentially confounding factors.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.33-33
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• 2022

Rice (Oryza sativa L.) is a widely studied domesticated model plant. Seed awning is an unfavorable trait during rice harvesting and processing. Hence, awn was one of the target characters selected during domestication. However, the genetic mechanisms underlying awn development in rice are not well understood. In this study, we analyzed the genes for awn development using a mapping population derived from a cross between the Korean indica cultivar 'Milyang23' and NIL4/9 (derived from a cross between 'Hwaseong' and O. minuta). Two quantitative trait loci (QTLs), qAwn4 and qAwn9 were mapped on chromosome 4 and 9, respectively, increased awn length in an additive manner. Through comparative sequencing analyses parental lines, LABA1 was determined as the causal gene underlying qAwn4. qAwn9 was mapped to a 199-kb physical region between markers RM24663 and RM24679. Within this interval, 27 annotated genes were identified, and five genes, including a basic leucine zipper transcription factor 76 (OsbZIP76), were considered candidate genes for qAwn9 based on their functional annotations and sequence variations. Haplotype analysis using the candidate genes revealed tropical japonica specific sequence variants in the qAwn9 region, which partly explains the non-detection of qAwn9 in previous studies that used progenies from interspecific crosses. This provides further evidence that OsbZIP76 is possibly a causal gene for qAwn9. The O. minuta qAwn9 allele was identified as a major QTL associated with awn development in rice, providing an important molecular target for basic genetic research and domestication studies. Our results lay the foundation for further cloning of the awn gene underlying qAwn9.

• 한국조경학회지
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• 제40권4호
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• pp.114-126
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• 2012

본 연구는 대규모 택지개발 예정지로 계획되어 있는 대구광역시 달성군 옥포면 논공읍 일대 약 $10km^2$를 대상으로 비오톱 유형분류를 기반으로 한 미 시각 측면에서의 경관가치 평가 모형을 설정해 보고, 이를 실사례지에 적용해 봄으로써 평가모형의 타당성을 검증해 보는데 가장 큰 의의를 두었다. 연구결과를 요약하면 아래와 같다. 비오톱 유형분류 결과, 평가대상이 되는 23개의 비오톱 유형과 이에 귀속되는 140개의 세부 비오톱 유형으로 분류되었다. 또한 평가지표 선정을 위한 설문조사는 1차, 2차, 3차 설문으로 나누어 수행하였다. 먼저 1차 설문분석은 우선 문헌연구 및 현장조사를 바탕으로 선정된 22개의 평가지표 항목들에 대한 중요도를 분석하는 단계이다. 다음으로 2차 설문분석은 요인분석을 실시, 내재된 상관관계를 이용하여 지표들을 재분류하였다. 3차 설문분석은 선정된 평가지표 항목의 가중치를 산정하는 단계로서, 평가지표 항목의 중요도 평균을 기준으로 합이 10이 되도록 표준화하는 방법을 사용하였으며, 2차 평가 시 각 지표항목의 점수에 가중치를 곱하여 최종 평가에 활용하였다. 이상과 같은 전문가 설문분석 결과, 최종 선정된 평가지표는 활력충전요소, 시각적 방해요소 등 총 19개 항목으로 조사되었다. 1차 평가 결과, 특별히 가치 있는 I등급은 식생이 풍부한 자연형 하천유형(D), 습지 및 늪지 유형(I) 등 총 7개 유형으로 나타났다. 또한 II등급으로는 식생이 풍부한 인공형 하천유형(E), 침엽수림 중심의 산림유형(Q) 등 총 4개 유형, III등급은 식생이 풍부한 자연형 실개천 및 도랑유형(F) 등 총 5개 유형으로 나타났다. 상대적으로 가치가 낮은 IV등급, V등급은 각각 식생이 빈약한 실개천 및 도랑유형(G) 등 총 2개 유형과 녹지가 빈약한 복합형 주거지역(B) 등 총 5개 유형으로 분석되었다. 2차 평가 결과, 경관 가치가 특별히 높은 비오톱 유형(1a, 1b)은 15개 공간으로 조사되었으며, 경관의 가치가 높은 유형(2a, 2b, 2c)은 총 28개 공간으로 분석되었다. 그러나 본 연구에서 제시된 경관평가 모형이 타 유사지역에서도 높은 적용성을 가지기에는, 본 연구에서 설정한 하나의 연구대상지만으로는 부족함이 있었던 바, 차후에는 다양한 사례지를 종합하고 표준화하여 객관성을 높여 나갈 필요가 있을 것으로 사료된다.

• Archives of Pharmacal Research
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• 제25권5호
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• pp.655-663
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• 2002

Liver fibrosis is a prepathological state wherein damaged liver tissues in chronic liver diseases, such as hepatitis, are not repaired to normal tissues, but converted to fibrous tissue. 5-(2-Pyrazinyl)-4-methyl-1,2-dithiol-3-thione (oltipraz), a cancer chemopreventive agent, is effective against a wide variety of chemical carcinogens. Recently, we reported that oltipraz inhibits liver fibrogenesis (Kang et al., 2002). In the present study, the effects of oltipraz in combination with dimethyl-4,4'-dimethoxy-5,6,5',6'-dimethylene dioxybiphenyl-2,2'-dicarboxylate (DDb) on dimethylnitrosamine (DMN)-induced liver fibrogenesis were assessed in rats. Oltipraz (30 mg/kg body weight, po, 3 times per week for 4 weeks) was found to inhibit the increases in plasma ALT, AST and bilirubin by DMN, whereas DDB (30 mg/kg body weight, po, 3 times per week for 4 weeks) attenuated the increases in the plasma ALT and bilirubin. The lowered plasma protein and albumin contents in DMN-treated rats were completely restored by oltipraz, but not by DDB. DDB decreases liver cell injury and inflammation through inhibition of nuclear factor-kB. DMN increased the accumulation of liver collagen, as indicated by the increase in the 4-hydroxyproline content in liver homogenates, which was reduced by treatment with oltipraz, but not by DDB. Given the differential effect between oltipraz and DDB, the potential enhancement of antifibrotic efficacy by the drugs was assessed in the animal model. Despite the minimal effect of DDB on DMN-induced fibrogenesis, DDB (5-25 mg/kg), administered together with oltipraz (25-5 mg/kg), showed an additive protective effect against hepatotoxicity and fibrosis induced by DMN, which was shown by the blood chemistry parameters and histopathological analysis. The adequate composition ratio of oltipraz to DDB was 5:1. These results provide information on the pharmaceutical composition, comprising of oltipraz and DDB as the active components, for the treatment and/or prevention of liver fibrosis and cirrhosis.