Towards a Strategic Approaches in Alternative Tests for Pesticide Safety

Yoonjeong Jang,Ji-Eun Kim,Sang-Hee Jeong,Myung-Haing Cho 한국독성학회 2014 Toxicological Research Vol.30 No.3

Pesticides have provided significant benefits including plant disease control and increased crop yields since people developed and utilized them. However, pesticide use is associated with many adverse effects, which necessitate precise toxicological tests and risk assessment. Most of these methods are based on animal studies, but considerations of animal welfare and ethics require the development of alternative methods for the evaluation of pesticide toxicity. Although the usage of laboratory animals is inevitable in scientific evaluation and alternative approaches have limitations in the whole coverage, continuous effort is necessary to minimize animal use and to develop reliable alternative tests for pesticide evaluation. This review discusses alternative approaches for pesticide toxicity tests and hazard evaluation that have been used in peer-reviewed reports and could be applied in future studies based on the critical animal research principles of reduction, replacement, and refinement.

Trifloxystrobin Induces Mitophagy via Mitochondrial Damage in HaCaT, Human Skin Keratinocytes

Yoonjeong Jang,Sang-HeeJeong 한국농약과학회 2016 한국농약과학회 학술발표대회 논문집 Vol.2016 No.10

Trifloxystrobin-induced mitophagy through mitochondrial damage in human skin keratinocytes

Jang, Yoonjeong,Kim, Ji-Eun,Jeong, Sang-Hee,Paik, Min-Kyoung,Kim, Jun Sung,Cho, Myung-Haing JAPANESE SOCIETY OF TOXICOOGICAL SCIENCES 2016 JOURNAL OF TOXICOLOGICAL SCIENCES Vol.41 No.6

<P>Trifloxystrobin is a strobilurin class fungicide, the mode of action of which is to block the mitochondrial electron transport chain and inhibit energy production in fungi. Although adverse effects have been reported by occupational or environmental exposure of fungicides, the pathophysiological mechanism in human cells remains poorly understood. In the present study, we investigated the impact of trifloxystrobin on exposed skin at the cellular organelle level using HaCaT, the human skin keratinocyte cell line. Cells were treated with trifloxystrobin for 48 hr and trifloxystrobin showed detrimental effects on mitochondria evidenced by altered mitochondrial membrane potential and morphology. To identify autophagic degradation of the damaged mitochondria, confocal imaging and Western blotting were performed. Trifloxystrobin induced autophagy-related proteins in HaCaT cells. The mitochondrial reactive oxygen species scavenger mitoTEMPO was applied to further explore the mechanism of trifloxystrobinmediated mitophagy in human skin cells. PINK1 and Parkin were overexpressed by trifloxystrobin, and mitoTEMPO alleviated the effects on mitophagy induction. Taken together, our findings indicated that mitochondrial damage and mitophagy may play a role in trifloxystrobin-induced toxicity in human keratinocytes and this could be suggested as a mechanism of cutaneous diseases developed by exposure.</P>

Towards a Strategic Approaches in Alternative Tests for Pesticide Safety

Jang, Yoonjeong,Kim, Ji-Eun,Jeong, Sang-Hee,Cho, Myung-Haing Korean Society of ToxicologyKorea Environmental Mu 2014 Toxicological Research Vol.30 No.3

Pesticides have provided significant benefits including plant disease control and increased crop yields since people developed and utilized them. However, pesticide use is associated with many adverse effects, which necessitate precise toxicological tests and risk assessment. Most of these methods are based on animal studies, but considerations of animal welfare and ethics require the development of alternative methods for the evaluation of pesticide toxicity. Although the usage of laboratory animals is inevitable in scientific evaluation and alternative approaches have limitations in the whole coverage, continuous effort is necessary to minimize animal use and to develop reliable alternative tests for pesticide evaluation. This review discusses alternative approaches for pesticide toxicity tests and hazard evaluation that have been used in peer-reviewed reports and could be applied in future studies based on the critical animal research principles of reduction, replacement, and refinement.

마방에서 음악장르에 따른 Jeju crossbred의 스트레스 변화 연구

장윤정(Yoonjeong Jang),최재영(Jae-Young Choi),이종안(Jongan Lee),강용준(Yongjun Kang),김나영(Nayoung Kim),윤민중(Minjung Yoon),신문철(Moon-Cheol Shin),신상민(Sang-Min Shin),선상수(Sangsoo Sun),이지웅(Jiwoong Lee) 한국생명과학회 2023 생명과학회지 Vol.33 No.12

본 연구는 Jeju crossbred 6두를 대상으로 다양한 장르(Classic, New Age, Rock) 의 음악 활용을 통해 기간에 따른 스트레스 저감 정도를 비교 분석하였다. 말의 스트레스 상태를 평가하기 위해 신경전달물질(cortisol, β-endorphin, dopamine, serotonin, oxytocin) 과 효소(CPK, Aldolase) 의 농도 분석을 진행하였다. Plasma를 통해 분석된 신경전달물질 결과는 다음과 같다. cortisol은 Classic과 New Age에서 음악 제공 기간에 따라 유의적으로 감소하였고, Rock은 증가하는 경향을 보였다. Dopamine은 New Age에서만 유의적으로 감소하였고, Classic은 감소하는 경향을 보였으며, Rock은 차이가 없었다. β-endorphin은 모든 장르에서 통계적 유의성은 없었으나, Classic과 New Ag에서 감소하고 Rock은 증가하는 경향을 나타냈다. Serotonin은 모든 장르에서 통계적 유의성이 없었다. Oxytocin은 Classic과 Rock에서 감소하였고, New Age는 차이가 없었다. Serum에 의해 분석된 스트레스 관련 효소의 농도는 다음과 같다. CPK는 New Age에서 유의적 차이로 감소하였고 음악 종료 후에 다시 증가하였다. Classic과 Rock은 유의적 차이가 없었다. Aldolase는 Classic과 New Age에서 유의적으로 감소하였고 음악 종료 후에 다시 증가하였다. Rock은 통계적 유의성이 없었다. 본 연구를 통해 Jeju crossbred의 심리적 안정을 위한 최적의 음악 장르로 Classic과 New Age가 적합하며, 음악 장르에 따른 생리학적 특성 구명을 통해 말의 사육 여건 개선 및 동물 복지 증진에 기여할 수 있을 것으로 기대한다. This study investigated the effects of three music genres (classical, new age, and rock) on the stress levels of six Jeju crossbred horses (Jeju horse × Thoroughbred) in a horse stable. The horses were exposed to the three genres for seven days, and their stress levels were measured by analyzing physiological markers, including neurotransmitter (cortisol, β-endorphin, dopamine, serotonin, and oxytocin) plasma levels and creatine phosphokinase (CPK) and aldolase serum levels. The neurotransmitter analysis showed significant differences in cortisol levels between classical and new age music exposure. Dopamine levels decreased significantly only with new age exposure. Although there were no significant differences in β-endorphin levels between the three genres, β-endorphin levels decreased with increasing classical and new age music playback times and increased with increasing rock music playback times. There were no significant differences in serotonin levels between the three genres. Oxytocin levels decreased significantly with exposure to classical and rock music. The CPK and aldolase analyses showed that CPK levels decreased significantly only with exposure to new age music and increased after playback ended, while aldolase levels decreased significantly with classical and new age music exposure and increased after playback ended. These findings suggest that classical music and new age are the optimal music genres for the psychological stability of Jeju crossbred horses. Playing back an appropriate music genre could be used to improve breeding and promote the welfare of Jeju crossbred horses.

Korean Validation of the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego Autoquestionnaire

Hyeona Yu(Hyeona Yu),Joohyun Yoon(Joohyun Yoon),Chan Woo Lee(Chan Woo Lee),Ji Yoon Park(Ji Yoon Park),Yoonjeong Jang(Yoonjeong Jang),Yun Seong Park(Yun Seong Park),Hyun A Ryoo(Hyun A Ryoo),Nayoung Cho 대한신경정신의학회 2022 PSYCHIATRY INVESTIGATION Vol.19 No.10

초임교사의 창의적 과학문제해결 수업 실행 및 관련 요인에 관한 질적 사례연구

이윤정(Yoonjeong Lee),조현희(Hyunhee Cho),장신호(Shinho Jang) 학습자중심교과교육학회 2020 학습자중심교과교육연구 Vol.20 No.9

This study explores the motivation for elementary teachers to implement Creative Problem Solving (CPS) in science class, the difficulties they face during the implementation, and the internal and experiential factors that led them to continue their practice despite the recognized difficulties. For these purposes, this study conducted a qualitative case study on two novice elementary teachers, who practiced CPS in their science classes. The major findings are as follows. Their positive memories about the science class and the science-related experience that they went through in childhood motivated them to choose science education as a major; and it led them to specialize science education in graduate school whereby they came to have interest in and even decided to practice CPS in the classroom setting. The reasons why the teachers became most interested in CPS were related to their perceptions of a good science instruction. However, despite such motives, the teachers had difficulties while implementing CPS in their science classes. During the four stages of CPS, the teachers had difficulties identifying problems that promote creative thinking and that are relevant to the students’ daily lives (the 1st stage); promoting the students to create and design their own ideas (the 2nd stage); mediating conflicts among the students (the 3rd stage); and establishing standards and methods for evaluating the students’ CPS skills (the 4th stage). Some of these difficulties were overcome during the class, but some had remained as they were. However, in spite of these difficulties, the teachers’ ongoing reflections on their teaching practices enhanced their beliefs in the effectiveness of CPS for their students and themselves and helped them construct the meanings of the CPS-centered instruction. Based on these findings, the study provided suggestions for science teacher education. 본 연구는 초등교사들이 창의적 과학문제해결 수업을 실행하게 된 동기와 실행과정에서 겪는 어려움, 그리고 이러한 어려움에도 불구하고 수업 실행을 지속하도록 이끄는 요인을 탐색하는 데 목적이 있다. 이를 위해 창의적 과학문제해결 수업을 실행한 두 초임교사에 대한 질적 사례연구를 실시하였으며, 수집된 자료를 지속적 비교법에 따라 분석하였다. 연구결과는 다음과 같다. 두 교사가 유년시절에 경험한 긍정적인 과학수업 및 체험 활동은 학부시절 과학교육을 전공하게 된 강력한 동기가 되었으며, 이는 대학원시절 창의적 과학문제해결 수업을 접하는 계기로 이어졌다. 두 교사가 다양한 과학수업방법 중에서도 창의적 과학문제해결 수업에 관심을 갖게 된 데에는 ‘좋은 과학수업’에 대한 교사의 인식, 신념 등과 같은 내적 요인이 관여하고 있었다. 그러나 두 교사는 수업을 실행하면서 수업 단계별로 여러 어려움을 겪게 된다. 1단계에서는 문제를 선정하고 학생들이 문제를 자기화하도록 돕는 데 어려움을 겪었으며, 2단계에서는 아이디어 생성과 설계를 촉진하는 데 어려움을 겪었다. 3단계에서는 아이디어 수렴 과정에서 발생하는 학생 간 갈등을 중재하는 데, 4단계에서는 창의적 문제해결력 평가를 위한 기준과 방법을 마련하는 데 어려움을 겪었다. 이러한 어려움은 수업 과정에서 일부 극복되기도 하였지만, 교사의 ‘감내하기’로 남는 경우도 있었다. 그럼에도 불구하고 수업실행에 대한 반성적 성찰을 통해 인식한 수업의 효과와 의미는 수업을 지속하는 원동력이 되었다. 본 연구에서는 이러한 결과를 바탕으로 창의적 과학문제해결 수업 각 단계에 필요한 교사역할을 탐색자, 촉진자, 중재자, 평가자로 상세화하고, 단계별 어려움에 대한 극복방안을 제시하였다. 나아가 창의적 과학문제해결 수업의 활성화를 위한 교사교육 방안을 제시하였다.

친환경 자동차용 인버터 파워모듈 레이저용접 적용시 IR레이저와 그린 레이저 특성 비교

장병운(Byungwoon Jang),강구삼(Kusam Kang),주범준(Beomjun Ju),권순형(Sunhyung Kwon),홍윤정(Yoonjeong Hong),백주환(Juhwan Baek) 한국자동차공학회 2023 한국자동차공학회 학술대회 및 전시회 Vol.2023 No.11

친환경 자동차용 인버터에 파워모듈을 조립할 때 기존에는 볼트 체결방식을 적용하였다. 하지만 볼트 체결방식은 조립공간, 중량, 체결시간 등 여러가지 단점이 있었고 이런 단점을 해결하기 위해 최근에는 레이저용접으로 조립을 하고있다. 이를 통해 중량 저감 및 연비향상, 조립시간 등을 개선할수 있게 되었다. 근래에는 그린레이저 장비의 용량이 증대되어 기존 IR레이저용접을 대체하여 파워모듈 용접을 할수 있게 되었다. 본 연구를 통해 IR레이저와 그린레이저 용접 특성을 파악하고 용접 적용부 재질, 두께 등 특성에 맞춰 적절한 방식을 선택 및 적용할 수 있을 것으로 기대한다. When assembling a power module in an inverter for an eco-friendly vehicle, a bolt fastening method was previously applied. However, the bolt fastening method had various disadvantages such as assembly space, weight, and fastening time, and to solve these disadvantages, laser welding is being used recently. Through this, it is possible to reduce weight, improve fuel efficiency, and improve assembly time. In recent years, as the capacity of green laser equipment has increased, power module welding can be performed by replacing the existing IR laser welding. Through this study, it is expected that IR laser and green laser welding characteristics can be identified, and appropriate methods can be selected and applied according to the characteristics such as the material and thickness of the welding application area.

소형 전기동력 덕티드팬 무인항공기 개발 및 비행시험

김태균(TaeGyun Kim),장윤정(YoonJeong Jang),김민규(Minkyu Kim),정준호(Junho Jeong),석진영(Jinyoung Suk),김승균(Seungkeun Kim) 한국항공우주학회 2017 한국항공우주학회 학술발표회 논문집 Vol.2017 No.4

Ephedrine-induced mitophagy via oxidative stress in human hepatic stellate cells

Lee, Ah Young,Jang, Yoonjeong,Hong, Seong-Ho,Chang, Seung-Hee,Park, Sungjin,Kim, Sanghwa,Kang, Kyung-Sun,Kim, Ji-Eun,Cho, Myung-Haing JAPANESE SOCIETY OF TOXICOOGICAL SCIENCES 2017 JOURNAL OF TOXICOLOGICAL SCIENCES Vol.42 No.4