Time-evolving genetic networks reveal a NAC troika that negatively regulates leaf senescence in <i>Arabidopsis</i>

Kim, Hyo Jung,Park, Ji-Hwan,Kim, Jingil,Kim, Jung Ju,Hong, Sunghyun,Kim, Jeongsik,Kim, Jin Hee,Woo, Hye Ryun,Hyeon, Changbong,Lim, Pyung Ok,Nam, Hong Gil,Hwang, Daehee National Academy of Sciences 2018 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.115 No.21

<▼1><P><B>Significance</B></P><P>Leaf senescence is regulated in a complex manner, involving time-dependent interactions with developmental and environmental signals. Genetic screens have identified key regulators of senescence, particularly late-stage senescence regulators. Recently, time-course gene-expression and network analyses, mostly analyses of static networks, have predicted many senescence regulators. However, senescence is defined by time-evolving networks, involving the temporal transition of interactions among senescence regulators. Here, we present time-evolving networks of NAM/ATAF/CUC (NAC) transcription factors, central regulators of leaf senescence in <I>Arabidopsis</I>, via time-course gene-expression analysis of NACs in their mutants. These time-evolving networks revealed a unique regulatory module of NACs that controls the timely induction of senescence-promoting processes at a presenescent stage of leaf aging.</P></▼1><▼2><P>Senescence is controlled by time-evolving networks that describe the temporal transition of interactions among senescence regulators. Here, we present time-evolving networks for NAM/ATAF/CUC (NAC) transcription factors in <I>Arabidopsis</I> during leaf aging. The most evident characteristic of these time-dependent networks was a shift from positive to negative regulation among NACs at a presenescent stage. ANAC017, ANAC082, and ANAC090, referred to as a “NAC troika,” govern the positive-to-negative regulatory shift. Knockout of the NAC troika accelerated senescence and the induction of other <I>NAC</I>s, whereas overexpression of the NAC troika had the opposite effects. Transcriptome and molecular analyses revealed shared suppression of senescence-promoting processes by the NAC troika, including salicylic acid (SA) and reactive oxygen species (ROS) responses, but with predominant regulation of SA and ROS responses by ANAC090 and ANAC017, respectively. Our time-evolving networks provide a unique regulatory module of presenescent repressors that direct the timely induction of senescence-promoting processes at the presenescent stage of leaf aging.</P></▼2>

전치태반의 임상적 고찰

정갑인,이해혁,이효환,유정완,남계현,이임순,이권해 순천향의학연구소 1998 Journal of Soonchunhyang Medical Science Vol.4 No.2

Objective : Our purpose was to make preparations of what for proper emergency care and delivery in order to improve maternal and fetal well-being. Methods : The study was undertaken for the clinical evaluation and statistical analysis on the patients with placenta previa who had been admitted and delivered at Soonchunhyang University Hospital from January, 1994 to May, 1998, retrospectively. Results : The incidence of placenta previa was 2.0%. Placenta previa has occurred more often in multigravida(92%) than primigravida(8%). Vaginal bleeding was most frequent(37.3%) presentation. The mean gestational age at the first bleeding episode was 31~35 weeks(46.4%). The type of placenta previa was totalis (31.3%), Partialis(18%), marginalis(32.7%), low lying(18%). Conclusion . This study indicates that the obstetrician and the pediatrician should be prepared for emergency care and delivery of the placenta previa patients, with the improvement of delivery room and neonatal intensive care unit.

과학 행사가 초등학생의 과학적 태도와 과학 탐구능력에 미치는 영향

정춘환,김효남 한국교원대학교 과학교육연구소 2003 청람과학교육연구논총 Vol.13 No.1

The purpose of this study is to investigate the effects of the various science events in the elementary school on the scientific attitude and scientific inquiry ability of the students and to suggest the future way of school science events. The survey for this study was accomplished with 209 students in the 5th and 6th graders of an elementary school located in small town. The results of this study is as follows: 1) The scientific attitude of boys was higher than of girls. 2) In comparing before and after participating school science events, the scientific attitude was changed a little, but the scientific inquiry ability was changed a lot. 3) Students who attended less than three science events had showed no improvement in scientific attitude and scientific inquiry ability. But students who attended more than seven science events had showed statistically meaningful improvement in scientific attitude and scientific inquiry ability.

학생 실험지도를 위한 실제 병렬 LC회로의 고찰

김정두,남효덕 영남이공대학 1973 論文集 Vol.2 No.-

In a parallel LC circuit containing a real inductor, the following were investigated by experiment. and also were compared to the theory: ① the ratio of the output to input voltages, ② Q of the circuit and ③ phase of the output signal relative to the input. By choosing component values to he confined co certain ranges, it was found that there is very good agreement between the experimental data and the theory for a real inductor. When (ω/ω。)<I, it was also found that the phase angle go to zero for a real inductor as compared to ½ for an ideal inductor.

유아 로타바이러스 설사증에 대한 IgY 난황 항체의 효과시험

정동혁, 박효선, 김경미, 정규항, 김강영, 정후길, 윤숭섭, 전호남, 강신영 충북대학교 동물의학연구소 2006 Journal of Biomedical and Translational Research Vol.7 No.2

본문참고

창의적 문제해결력 중심의 수학 교육과정 개발 및 적용 : 초등학교수준을 중심으로

김정효,권오남 한국수학교육학회 2000 初等 數學敎育 Vol.4 No.2

본 연구는 창의적 문제해결력 신장을 위한 수학교육과정을 개발하고, 그 적용효과를 알아보고자 하는데 목적을 둔다. 개발된 창의적 문제해결력 중진을 위한 수학교육과정은 수학의 개념적 지식(내용)과 절차적 지식(기능), 그리고 창의적 사고요소(확산적 사고와 비판적 사고) 등 3가지 요소를 기반으로 하였다. 세부적으로 보면 수학교육과정의 내용을 개념적 지식과 절차적 지식으로 이원화하여, 개념적 지식은 수학의 본질을 구성하는 4개의 주제를 중심으로 6개 하위영역을 연결하여 총괄 개념, 학년별 개념, 그리고 하위개념으로 구성하였고, 절차적 지식은 사고요소, 계산기능요소, 수학적 도구와 기술사용 등 3요소로 구성하였다. 한편 창의적 사고요소는 이러한 교육과정내용을 PBL을 기반으로 하는 단원개발을 하는 과정에서 융합되도록 하였다. 그 적용효과를 검증하기 위해서는 초등학교 5학년을 대상으로 1학기간 투입하고 수학적 창의적 문제해결력 검사를 실시하여 집단간 점수차이를 검증하였다. 그 결과 본 교육과정은 아동의 수학적 창의적 문제해결력 신장에 효과가 있는 것으로 드러났다. The purpose of this study is to develop and implement an alternative elementary mathematics curriculum to enhance creative problem solving ability. The curriculum consisting of three main elements was developed. The three elements are content knowledge, process knowledge and creative thinking skills. The curriculum contents and the units were developed by mathematics educators, elementary educators, psychologists, elementary school teachers and curriculum specialists for 3 years. In order to test the effectiveness of the developed curriculum, the 5 units based on a problem-based-learning(PBL) method were implemented in a 5th grade class as an experimental group during the second semester. For the comparison group the ordinary lesson based on the 6th national mathematics curriculum was implemented during the same period. Performance assessment was developed and used for the pre and post test. T-test was used to testify that the effect of the curriculum is statistically significant. The results of the test showed that the experimental group progressed significantly in the creative problem solving ability, but the comparison group did not.

감단자(시단자)의 관능적 및 텍스쳐 특성

이효지,백현남,김정원 한국조리과학회 2004 한국식품조리과학회지 Vol.20 No.6

The objective of this study was to seek the best recipe for making Gamdanja. Gamdanja is a kind of rice cake made from persimmon extract and waxy flour, with a little salt mixed into the waxy flour. The method involved boiling the persimmon extract and beating in the waxy rice powder until all the waxy flour had been added.The procedure was as follows: Gamdanja containing different ratios of ingredients, such as persimmon extract (23, 23.5 and 24 hrs) and waxy rice flour (160 and 180g). The most desirable recipe was determined after sensory examination and mechanical tests using texture, moisture content and colorimeter measurements. The results of the sensory evaluation showed that Gamdanja made using persimmon extracted for 23.5 hrs, with the additional of 160g of waxy flour gave the higher scores for QDA profile, chewiness, delicacy and after swallowing preference than the other ratios. The results of the acceptance test also showed that the Gamdanja made using the persimmon extracted for 23.5 hrs with 160g of waxy rice flour was the best mix in every respect, such as for color and overall acceptability. In the textural analysis of Gamdanja, the hardness, adhesiveness, gununiness and chewiness were increased by the additiong of furtherwaxy flour. The moisture content of Gamdanja with persimmon extracted for 23 Ins was higher than those extracted for 23.5 and 24 hrs. The L-, a- and b-values of Gamdanja were increased with decreasing waxy flour. The sensory and mechanical examinations showed the overall quality of Gamdanja had positive correlations with delicacy and color, but negative correlations with hardness, adhesiveness, gumminess, and chewiness. As a result of these tests, the most desirable recipe for the Gamdanja was persimmon extracted for 23.5 hrs with the additional of 160g of waxy rice flour, containing I% salt and a moisture content of 45.87%.

창의적 문제해결력 신장을 위한 수학교육과정개발 : 개념적 지식을 중심으로 Theme-Based Reconstruction of Conceptual Knowledge

김정효,권오남 이화여자대학교 교과교육연구소 1999 교과교육학연구 Vol.3 No.2

본 연구는 창의적 문제해결 신장을 위한 수학 교육과정을 재구성하기 위한 구성체제의 개발과 그에 따른 개념적 지식의 재구성에 목적을 둔다. 개발되어진 교육과정의 틀은 개념적 지식과 절차적 지식을 이원화하여 개념간의 연결을 도모하는 한편 절차적 지식의 한 요소로서 사고력을 강조하여 교육과정에서 사고력변인의 주요성을 가시화하였다는 특징을 가진다. 특히 개념적 지식은 수학의 본질적 요소와 관련한 연결주제를 선정하여 이를 중심으로 개념간의 관계에 대한 이해를 도모함으로써 수학이란 학문의 지식구조에 대한 깊은 이해를 가지도록 하였다. 이는 수학적 문제사태에서 학습자가 확산적 사고와 비판적 사고에서 사용할 수 있는 지식기반을 풍부히 가질 수 있도록 하기 위함이었다. 개발되어진 수학교육과정틀을 통해 구체적인 초등교육과정을 제시하였는데 이는 정보화사회에서 요구되는 창의적인 문제해결력을 교육하기 위한 체계적이고 실질적인 초등 수준의 수학교육과정이 될 수 있을 것으로 기대된다. This study is a part of a research to develop the elementary mathematics curriculum to enhance creative problem-solving abilities through reconstructing and specifying national mathematics curriculum. The developed mathematics curriculum is characterized as division of conceptual knowledge and procedural knowledge, and emphasis on relationship among concepts. The explicit network among concepts and between concepts and skills in the curriculum can help children have a powerful knowledge base for divergent and critical thinking in mathematical problem solving. for the relationship among mathematical concepts, the conceptual knowledge is reconstructed on the four themes, such as algorithm, relationship, pattern and generalization, and representation, which stems from the nature of mathematics. The results of reconstruction are presented in the form of matrix, such that the vertical axis represents how the concepts within each strand of mathematics curriculum are unified, while the horizontal axis shows how the concepts across the strands are related in terms of the themes.

CPW 급전을 이용한 평면형 반원 UWB 안테나 설계

이효경,이정남,박종권 한밭대학교 정보통신전문대학원 2005 정보통신전문대학원 논문집 Vol.3 No.1

본 논문에서는 UWB 통신 시스템에 사용될 수 있는 CPW 급전 구조을 이용한 평면형 반원 UWB 안테나를 설계하였다. 제안된 안테나를 설계하기 위해 CST사의 MWS를 이용하였다. 유전율이 4.5이고, 두께가 0.762mm인 TMM4 기판을 사용하였다. 시뮬레이션 결과 VSWR≤2를 기준으로 2.6GHz에서 12.2GHz까지 UWB 전체 대역을 만족한다. 제안된 안테나의 group delay 변화량이 1ns 미만으로 UWB 통신 시스템 응용에 적합한 안테나이다. In this paper, a planar half-disk ultra-wideband (UWB) antenna fed by CPW is designed for UWB communications. We have used the Microwave Studio of CST to simulate the proposed antenna. It is designed to work an a substrate TMM4 of thickness 0.762mm and relative permittivity 4.5. The proposed antenna covers the entire UWB band (3.1 GHz ~ 10.6 GHz) from 2.6 GHz to 12.2 GHz for VSWR≤2. Group delay variation is less than 1 ns, thus indicating the proposed antenna a good candidate for UWB applications.

Al₂O₃-ZrO₂/Al₂O₃-TZP 세라믹스의 기계적 특성 및 열충격 거동

서정철,박재성,남효덕 영남대학교 공업기술연구소 1999 工業技術硏究所論文集 Vol.27 No.2

The effects of the addition of either monoclinic ZrO2(pure) or tetragonal ZrO2 containing 5.35wt% Y2O3 (Y-TZP) on the mechanical properties and thermal shock resistance of Al2O3 ceramics were investigated. The addition of ZrO2(m) and Y-TZP increased sintered density of Al2O3. The Vickers hardness also increased as the volume fraction of Y-TZP increased going through a maximum at 20wt%. The hardness of the specimens was found to be dependent on the sintered density. The higher volume fraction of either ZrO2(m) or Y-TZP resulted in the higher fracture toughness of the composite was. This result may be taken as evidence that toughening of Al2O3 can be achieved by not only the transformation toughening but microcrack toughening of ZrO2. The thermal shock property for Al2O3-ZrO2 composites was improved by increasing the volume fraction of monoclinic ZrO2(pure). The grain size increased as the volume fraction of ZrO2 did.