Differential Modulation of Astrocyte Cytokine Gene Expression by a Synthetic HIV GP41 Peptide in Astroglioma Cell Line, T98G

Younghae Chong,Ju-Young Seoh,Hae Kyung Park 大韓微生物學會 1996 大韓微生物學會誌 Vol.31 No.6

Identification of Genes Related to Fungicide Resistance in Fusarium fujikuroi

( Younghae Choi ),( Boknam Jung ),( Taiying Li ),( Jungkwan Lee ) 한국균학회 2017 Mycobiology Vol.45 No.2

We identified two genes related to fungicide resistance in Fusarium fujikuroi through random mutagenesis. Targeted gene deletions showed that survival factor 1 deletion resulted in higher sensitivity to fungicides, while deletion of the gene encoding F-box/WD-repeat protein increased resistance, suggesting that the genes affect fungicide resistance in different ways.

Stability of fixed points on piecewise smooth systems

Younghae Do 한국산업응용수학회 2005 한국산업응용수학회 학술대회 논문집 Vol.- No.-

The stability type of fixed points of continuously differential dynamical systems can be determined by their Jacobian information. But in practical situation, we often meet piecewise smooth maps with a border separating two smooth regions. The discontinuous change in the Jacobian elements results in many atypical bifurcation phenomena, which is called border collision bifurcations, for instance a periodic orbit turning directly into a chaotic orbit, or multiple attractors coming into existence or going out of existence as the parameter is varied across some critical bifurcation value, etc. Recent research has shown the new type of border collision bifurcations, which is called the dangerous border collision bifurcations where a fixed point remains stable at both sides of the critical bifurcation point, but the orbit becomes unbounded at the critical point of bifurcation. Possibility for occurring such dangerous border collision bifurcations has been pointed out through numerical exploration but the mechanism causing its occurrence is not yet known. In the present paper, we focus on determining the stability type of fixed points of piece￢wise smooth systems. Specifically, consider non-differentiable fixed points which are located exactly on the border. In order to investigate the behavior of trajectories on piecewise linear systems having such fixed points, we consider the angle dynamics of the circle map defined on the unit circle with the assigned dilation ratios generated by the original piecewise linear system. From dynamical features of the circle map on the unit circle, we can measure the stability type of fixed points, which can be compared to the role of the magnitude of eigenvalues in continuously differential dynamical systems. Our results will help to understand the mechanism of such dangerous border collision bifurcations.

Stability of attractors formed by inertial particles in open chaotic flows

Younghae Do,Ying-Cheng Lai,Hun Ki Baek 한국산업응용수학회 2005 한국산업응용수학회 학술대회 논문집 Vol.- No.-

Particles having finite mass and size advected in open chaotic flows can form attractors behind structures. Depending on the system parameters, the attractors can be chaotic or nonchaotic. But, how robust are these attractors? In particular, will small, random perturbations destroy the attractors? Here, we address this question by utilizing a prototype flow system: a cylinder in a two-dimensional incompressible flow, behind which the von Karman vortex street forms. We find that attractors formed by inertial particles behind the cylinder are fragile in that they can be destroyed by small, additive noise. However, the resulting chaotic transient can be superpersistent in the sense that its lifetime obeys an exponential-like scaling law with the noise amplitude, where the exponent in the exponential dependence can be large for small noise. This happens regardless of the nature of the original attractor, chaotic or nonchaotic. We present numerical evidence and a theory to explain this phenomenon. Our finding makes direct experimental observation of superpersistent chaotic transients feasible and it also has implications for problems of current concern such as the transport and trapping of chemically or biologically active particles in large-scale flows.

Challenge to the top

Younghae Do 한국산업응용수학회 2009 한국산업응용수학회 학술대회 논문집 Vol.4 No.2

Fluid dynamics is one of the most challenging and exciting fields of scientific activity simply because of the complexity of the subject and the breadth of the applications. The quest for deeper understanding has inspired numerous advances in applied mathematics, computational physics, and experimental techniques. To create key growth-generating fields, it is necessary to develop the technique for analyzing fluid flows. Our research team, Computation and Methodology in Applied Fluid Dynamics, at Kyungpook National university focuses on the mathematical modeling for fluid systems, the development of problem-solving methodologies and robust tools for solution of fluid problems, and analysis of mathematical theories for phenomena observed in fluid dynamics.

Crop phenomics to genomics in the mathematical point of view

Younghae Do 한국육종학회 2023 한국육종학회 공동학술발표집 Vol.2023 No.-

Dangerous border-collision bifurcations

Younghae Do,Sang Dong Kim,Philsu Kim,Hun Ki Baek 한국산업응용수학회 2006 한국산업응용수학회 학술대회 논문집 Vol.1 No.1

In this talk, we show our current results for dangerous border collision bifurcation characterized by exhibiting a stable fixed point before and after the critical bifurcation point, but the unbounded behavior of orbits at the critical bifurcation point. Dangerous bifurcations reveal a matter of serious concern for practical systems modeled by piecewise smooth maps, because there is no way of giving any signal of the impending collapse or unboundedness. Through the talk, we introduce the mechanism causing the occurrence of such bifurcations. Based on this mechanism, we find the qualitative type of the fixed point at the critical bifurcation value and show nonsmooth invariant manifolds of such fixed point, which can not be seen in linear systems.

A Phenomenological Study on Korean Drug Addicts' Experiences

Younghae Kim,Yeongkyeong Kim,Jinhyang Yang,Younja Yoo,Myungok Cho,Youngsook Tae 질적연구학회 2004 질적연구 Vol.5 No.1

놀이중심교육에 대한 장애유아 교사의 인식

안영혜 ( Younghae An ) 사단법인 아시아문화학술원 2021 인문사회 21 Vol.12 No.4

본 연구의 목적은 장애유아 교사들의 놀이중심교육에 대한 인식을 알아보기 위해, P시의 D장애전문어린이집 교사 5명을 대상으로 오지연(2020)이 개발한 면담 질문지를 활용하여 심층면담을 실시하였고, 이를 통해 수집한 자료를 질적 분석하였다. 본 연구결과 첫째, 개정 누리과정과 장애 유아 놀이의 중요성에 대한 인식은 높으나 일반 유아와는 달리 적용해야 한다고 하였다. 둘째, 장애유아들의 발달특성과 놀이상황에 따라 다양한 놀이지원과 교사역할수행을 하면서도 놀이중심교육에 대한 딜레마를 경험하였고 장애 특성에 따른 다양한 놀이 요구 및 지원 등의 어려움이 있었다. 셋째, 교사계획놀이 중심에서 장애유아 흥미중심의 놀이환경제공에 중점을 두었고 전문화된 장애유아 놀이중심 교육과정이 필요하다고 인식하였으며, 성공적인 놀이중심교육 실행을 위해 현장중심의 지원체계 강화 및 학부모를 위한 놀이이해교육, 특수보육교직원 인력충원, 다양한 체험활동을 위한 예산지원 등의 정책적 지원을 요구하였다. 본 연구는 장애유아 교육현장에서의 개정 누리과정의 현장 적용을 위한 기초자료 제공에 도움이 될 것으로 기대한다. The purpose of this study was to figure out the awareness of play-based education in child care teachers for children with disabilities. An in-depth interview was conducted by using the interview questionnaire developed by Oh (2020) targeting 5 teachers at D specialized child-care center for young children with disabilities in P city. The qualitative data that were collected through this were analyzed. As a result of this study, first, the awareness on the importance of the 2019 revised Nuri curriculum and of the play for children with disabilities was high. But they perceived that it should be applied differently from general young children. Second, while performing various play support and teachers roles according to developmental characteristic and a play situation in young children with disabilities, They experienced dilemma for play-based education, and there were difficulties in various play requests and supports according to the characteristics of the disabled. Third, in terms of centering on the teacher planning play, the offer of the interest-oriented play environment for disabled toddlers was emphasized. The necessity was perceived for the specialized play-based curriculum for disabled toddlers. and to implement the successful play-based education, a policy-based support was requested such as the strengthening of the field-centered support system, the play understanding education for parents, the recruitment of special child care staff, and the budget support for a variety of the experience activities. This study is expected to be helpful in providing basic data for the field application of the revised Nuri course in the educational field for children with disabilities.

한국 전·후기 노인의 삶의 질 관련요인과 성별 차이

정영해(Younghae Chung),조유향(Yoo Hyang Cho) 한국농촌의학 지역보건학회 2014 농촌의학·지역보건 Vol.39 No.3

본 연구는 노인의 삶의 질 관련 요인을 파악하고, 관련 요인을 통제한 상태에서 남·녀 노인의 삶의 질에 차이가 있는지 국민건강영양조사 제5기 1차 년도 자료를 사용하여, 65세 이상 노인 1,339명을 대상으로 하였다. 자료분석 방법은 층과 집락 가중치를 지정하여 SPSS 20.0 복합표본분석방법으로 분석하였는데, 연령과 성별에 따른 일반적 특성과 건강행위 및 건강상태의 차이는 로지스틱회귀분석을, 삶의 질 차이는 일반선형모형분석을, 삶의 질 관련요인은 후진제거방법을 이용한 일반선형모형으로 파악하였으며, 성별의 차이 역시 일반선형모형을 이용하여 검증하였다. 일반적 특성에서는 교육수준(p<.001)과 경제수준(p=.005), 동거여부(p<.001)가 성별에 따라 차이가 있었으나, 거주지역은 차이가 없었으며, 건강행위는 흡연(p<.001), 음주(p<.001), 운동(p=.045)에서 차이를 보였고, 건강상태에서는 비만정도(p<.001), 만성질환유무(p<.001), 스트레스(p<.001), 우울(p=.005), 자살사고(p<.001), 주관적 건강상태(p<.001)이 성별에 따라 차이가 있는 것으로 나타났다. EQ-5D는 노년전기, 후기 모두 여자노인보다 남자노인의 점수가 높았으며, 운동능력, 자가간호능력, 일상생활불편감, 통증/불편감, 불안/우울 등 모든 하위영역에서는 여자노인의 삶의 질이 남자보다 낮았다. 삶의 질 관련변수는 교육수준(p=.001), 경제상태(p=.001), 만성질환유무(p=.052), 동거여부(p=.002), 주관적건강상태(p<.001), 연령(p<.001), BMI(p=.045)로, 이 변수들은 노인 삶의 질의 31.5%를 설명하였다. 노년기에서도 성 인지적 차이를 감안한 접근방안이 필요함을 제언한다. Objectives: As a sequel to the former analysis of the quality of life (QoL) among young-old and old-old in Korea, this research was aimed to identify factors related to the quality of life and the gender difference after controlling for the related factors among Korean elderly. Methods: Selected elderly data of 1,339 subjects from the 5th Korea National Health and Nutrition Examination Survey conducted in 2010 was analyzed. In this survey, QoL was measured using Euro Quality of Life (EQ-5D) instrument. Data were analyzed using complex survey data analysis on IBM-SPSS 20.0. The related factors were identified using general linear models with backward elimination. The gender difference was tested also using general linear models. Results: The distributions of educational level, family income level, and presence of cohabitant were different between male and female elderly in both young-old and old-old age group. So were the health behaviors and perceived health, and experience of stress, depression, and suicidal thoughts. QoL and its subscales- mobility, self care, daily living, pain and discomfort, and anxiety and depression- were consistently better among male elderly regardless of age group. Among the variables considered, education, family income level, presence of cohabitant, perceived health, age group and BMI were found to be related to the QoL at p=.05, and presence of chronic diseases at p=.10. The difference in QoL between male and female elderly after controlling for the variables was statistically significant. Conclusion: Improving QoL is particularly important for the elderly. In order to improve QoL of the elderly, age- and gender- differences need to be considered when developing services and programs for the elderly.