• Title/Summary/Keyword: persistence

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Residual Pattern of Pesticide, Chlorfluazuron in Perilla Leaves Under Plastic House (들깻잎 재배 중 chlorfluazuron의 잔류량 변화 및 잔류분석법 시험)

  • Lee, Min-Ho;Kim, Seok-Ho;Park, Young-Guin;Jo, Gyeong-Yeon;Shin, Byung-Gon;Kim, Jong-Han;Kwon, Chan-Hyeok;Sohn, Jae-Keun;Kim, Jang-Eok
    • The Korean Journal of Pesticide Science
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    • v.11 no.2
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    • pp.106-116
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    • 2007
  • Pesticide, chlorfluazuron was subjected to determine the safety of terminal residues at the harvesting date of perilla leaves cultivated in plastic house. After the pesticide applied on a foliar spray in 2005 and 2006, leaf persistence of its residue was analysed for 10 days before leaf harvest. The degradation rate of chlorfluazuron in the leaf was 32.3 %(standard application), 43.6 %(double application) and 78.0 %(standard), 80.4 %(double) at second and tenth day, respectively, under analysis of GC/ECD in 2005. The degradation rate of chlorfluazuron in the leaf was 33.1 %(GC/ECD analyze), 34.0 %(HPLC/UVD analyze) and 77.9 %(GC/ECD), 78.4 %(HPLC/UVD) at second and tenth day, respectively, under the standard level of pesticide in 2006. The biological half-life of the chlorfluazuron residue was estimated by the regression equation calculated from daily dissipation of pesticide in the perilla leaves. The longest half-life of the chlorfluazuron residue in perilla leaves was 5.5 days. The maximum residual limit(MRL) for chlorfluazuron based on the longest half-life was estimated 2.0ppm at harvesting day, 2.5ppm at second day and 7.1ppm at tenth day before leaf harvesting of perilla.

CHARACTERISTICS OF DETAINED DELINQUENT ADOLESCENTS AND VARIABLES RELATED TO THE REPEATED CRIME DURING 6 MONTHS AFTER RELEASE (구속된 비행 청소년들의 특성 및 석방 후 6개월간 재범여부와 관련된 변인)

  • Kim, Won-Sik;Koh, Seung-Hee;Koo, Yong-Jin;Kim, Hong-Chang;Suh, Dong-Hyuck;Chung, Sun-Ju
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.10 no.2
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    • pp.201-211
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    • 1999
  • Objectives:This study investigated the characteristics of detained delinquent adolescents and variables related to the repeated crime during 6 months after release. Methods:The socio-demographic and crime-related characteristics of 73 detained adolescents were evaluated by semi-structured interviews and police records, and the psychological characteristics of them measured by the MMPI. We also compared the characteristics between subjects with and without repeated crime during 6 months after release. Results:1) Most of detained adolescents had families with low socioeconomic status(77%) and broken families(48%). Sixty-six percent of them were dropped out of school. The most frequent crime pattern was theft(49%), and with accomplice(77%). Seventy-five percent of total subjects had the records of previous conviction. Of the previous convictions, seventy-eight percent was same with the present crimes. 2) Subjects with repeated crime during 6 months after release were younger and had higher T-score on Pa scale of MMPI than the subjects without repeated crime. More adolescents with repeated crime had broken families than those without repeated crime. They also showed the crime-related characteristics of higher percent of theft among crime patterns, higher incidence of previous conviction, younger age of the first crime, and shorter crime-free duration from the last to present crime. Conclusion:These results of present study suggest that the development and the persistence of adolescent delinquency would be resulted from interaction of factors of individual, family, school, and community. By the comparison between subjects with and without repeated crime, it was found that familial dysfunction, younger age at first crime, presence of previous conviction might be the risk factors for repeated delinquency. To prevent repeated crime of delinquent adolescents more effectively, early therapeutic intervention and the development of programs to help adaptation in school and community would be essential.

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Generation of Transgenic Rice without Antibiotic Selection Marker through Agrobacterium-mediated Co-transformation System (아그로박테리움 동시 형질전환 시스템을 통한 항생제 선발 마커가 없는 형질전환벼의 생산)

  • Park, Soo-Kwon;Kwon, Tack-Min;Lee, Jong-Hee;Shin, Dong-Jin;Hwang, Woon-Ha;Song, You-Chun;Cho, Jun-Hyun;Nam, Min-Hee;Jeon, Seung-Ho;Lee, Sang-Yeol;Park, Dong-Soo
    • Journal of Life Science
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    • v.22 no.9
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    • pp.1152-1158
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    • 2012
  • Development of transgenic plant increasing crop yield or disease resistance is good way to solve the world food shortage. However, the persistence of marker genes in crops leads to serious public concerns about the safety of transgenic crops. In the present paper, we developed marker-free transgenic rice inserted high molecular-weight glutenin subunit (HMW-GS) gene ($D{\times}5$) from the Korean wheat cultivar 'Jokyeong' using Agrobacterium-mediated co-transformation method. Two expression cassettes comprised of separate DNA fragments containing only the $D{\times}5$ and hygromycin resistance (HPTII) genes were introduced separately into Agrobacterium tumefaciens EHA105 strain for co-infection. Each EHA105 strain harboring $D{\times}5$ or HPTII was infected into rice calli at a 3: 1 ratio of EHA105 with $D{\times}5$ gene and EHA105 with HPTII gene expressing cassette. Then, among 66 hygromycin-resistant transformants, we obtained two transgenic lines inserted with both the $D{\times}5$ and HPTII genes into the rice genome. We reconfirmed integration of the $D{\times}5$ and HPTII genes into the rice genome by Southern blot analysis. Wheat $D{\times}5$ transcripts in $T_1$ rice seeds were examined with semi-quantitative RT-PCR. Finally, the marker-free plants containing only the $D{\times}5$ gene were successfully screened at the $T_1$ generation. These results show that a co-infection system with two expression cassettes could be an efficient strategy to generate marker-free transgenic rice plants.

Effect of SCODMn and pH Adjustment on Physicochemical Characteristics in Liquid Fertilizer Production Process Using Swine Manure (SCODMn 농도 및 pH 조정이 양돈분뇨의 후숙발효과정에 미치는 이화학적 영향)

  • Hong, In-Gi;Kim, Soo-Ryang;Lee, Myung-Gyu
    • Journal of Animal Environmental Science
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    • v.18 no.sup
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    • pp.13-20
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    • 2012
  • This research investigated the effect of $SCOD_{Mn}$ concentrations and pH adjustment at the stage before land application, namely 2nd-aeration treatment stage of liquid fertilizer in the liquid fertilizer treatment process of swine manure on the physicochemical compositions of 2nd-aeration treated liquid fertilizer. The liquid fertilizer used in this research is the alkaline fermented liquid fertilizer of swine manure more than pH 9.0 through aeration treatment (Alkaline fermentation treatment group). About the alkaline liquid fertilizer, phosphate neutralization treatment was conducted with phosphoric acid and it was a phosphate neutralization treatment group. In 2nd-aeration treatment of liquid fertilizer for 30 days, each group was divided into alkaline treatment groups (T-1, T-2, and T-3) and phosphate neutralization treatment groups (T-4, T-5, and T-6) according to early $SCOD_{Mn}$ concentrations. The research results are as follows. 1. As for $SCOD_{Mn}$ reduction rate, the average 29.9% in alkaline treatment groups and the average 36.9% in phosphate neutralization treatment groups were shown and so the relatively high reduction rate was shown in phosphate neutralization treatment groups. 2. After finishing the experiment, the group of the lowest $SCOD_{Mn}$ concentrations was the phosphate neutralization treatment group, T-6 with the lowest inflow concentrations. In case the final goal level of 2nd-aeration treated liquid fertilizer is assumed as concentrations less than $SCOD_{Mn}$ 3,000 ppm, it would be desired that inflow concentrations of 2nd-aeration treatment groups are adjusted less than $SCOD_{Mn}$ 5,500 ppm. 3. As for the persistence rate of nitrogen, the average 29.3% in alkaline treatment groups and the average 38.9% in phosphate neutralization treatment groups were shown and so phosphate neutralization treatment groups showed the relatively low loss rate of nitrogen, meanwhile, in the case of T-P, phosphate neutralization treatment groups maintained high concentrations (average 1,473 ppm). 4. In the event of 2nd-aeration treatment of liquid fertilizer, "alkaline fermentation treatment" condition in 'low phosphate-low nitrogen' type and "phosphate neutralization treatment" condition in 'high phosphate-high nitrogen' type are expected to be favorable.

Amounts of physical activity and sedentary behavior patterns in older adults: using an accelerometer and a physical activity diary (노인의 신체활동량 및 좌식행동패턴 : 가속도계와 신체활동일기를 이용하여)

  • Go, Na-Young;Ndahimana, Didace;Kim, Eun-Kyung
    • Journal of Nutrition and Health
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    • v.52 no.1
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    • pp.36-46
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    • 2019
  • Purpose: This study evaluated amounts of physical activity and sedentary behavior patterns in older adults using an accelerometer and physical activity diary. Methods: Forty-nine older adults (male 26, female 23) participated in this study. They wore a triaxial accelerometer (ActiGraph wGT3X-BT) for one week and wrote a physical activity diary concurrently for three days. Amounts of physical activity, sedentary behavior patterns, and percentage of meeting the World health organization (WHO) physical activity guidelines were analyzed using an accelerometer. In addition, the contents recorded in the physical activity diary were reclassified to 18 levels and the average daily times spent on each level and physical activity level (PAL) were calculated. Results: The subjects were sitting more than half of the day except for bedtime and shower time (59.2%). The numbers of prolonged ${\geq}30$, 40 minutes sedentary bouts were significantly higher in males ($3.10{\pm}1.34$, $1.78{\pm}1.09$, respectively) than in females ($2.34{\pm}1.22$, $1.32{\pm}1.07$, respectively) and the number of breaks per sedentary hour was significantly less in males ($5.74{\pm}0.89$) than in females ($6.44{\pm}0.71$). Among the activities corresponding to sedentary behavior surveyed by the physical activity diary, only the amount of time spent 'resting, speaking and watching TV' showed a significant correlation with the sedentary behavior pattern measured by the accelerometer. The persistence of sedentary behavior was interrupted primarily when low intensity activity was performed. Only 22.4% of the subjects met WHO physical activity guidelines. Conclusion: Based on these results, the physical activity guidelines for older adults should be developed that reflects the appropriate strength, including low activity level and maintenance time of moderate to vigorous physical activity.

On the Persistence of Warm Eddies in the East Sea (동해 난수성 에디의 장기간 지속에 관하여)

  • JIN, HYUNKEUN;PARK, YOUNG-GYU;PAK, GYUNDO;KIM, YOUNG HO
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.24 no.2
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    • pp.318-331
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    • 2019
  • In this study, comparative analysis is performed on the long-term persisted warm eddies that were generated in 2003 (WE03) and in 2014 (WE14) over the East Sea using the HYCOM reanalysis data. The overshooting of the East Korea Warm Current (EKWC) was appeared during the formation period of those warm eddies. The warm eddies were produced in the shallow Korea Plateau region through the interaction of the EKWC and the sub-polar front. In the interior of the both warm eddies, a homogeneous water mass of about $13^{\circ}C$ and 34.1 psu were generated over the upper 150 m depth by the winter mixing. In 2004, the next year of the generation of the WE03, the amount of the inflow through the western channel of the Korea Strait was larger, while the inflow was lesser than its climatology during 2015 corresponding to the development period of the WE14. The above results suggest that the heat and salt are supplied in the warm eddies through the Tsushima Warm Current (TWC), however the amount of the inflow through the Korea Strait has negligible impact on the long-term persistency of the warm eddies. Both of the warm eddies were maintained more than 18 months near Ulleung island, while they have no common feature on the pathways. In the vicinity of the Ulleung basin, large and small eddies are continuously created due to the meandering of the EKWC. The long-term persisted warm eddies in the Ulleung Island seem to be the results of the interaction between the pre-existed eddies located south of the sub-polar front and fresh eddies induced by the meanderings of the EKWC. The conclusion is also in line with the fact that the long-term persisted warm eddies were not always created when the overshooting of the EKWC was appeared.

Exploring the Possibilities of Character Education in Various Interaction-based Mentor Program: Focusing on "Becoming a Science Teacher" Activity (다양한 상호작용 기반의 멘토멘티 프로그램에서 나타난 인성 교육 가능성 탐색 -"과학 선생님 되어보기" 활동을 중심으로-)

  • Kim, Sunhee;Shin, Donghee
    • Journal of The Korean Association For Science Education
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    • v.39 no.1
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    • pp.13-33
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    • 2019
  • The purpose of this study is to clarify the possibility of the character education and the concrete implementation process in the field of science education in accordance with the social demand for character education. Based on this purpose, the researchers tried to understand the specific character elements appearing in various science learning situations and to understand the qualities of each specific character elements that can be emphasized through science learning and the aspect of expression process in related learning situations. The researchers selected 11 students from the 7th and 8th graders in Seoul and developed and applied the 'Become a Science Teacher' mentor program in 2014 and 2015. Data collection was conducted through class recordings, mentor teachers' and assistant teacher's journal, artifacts, student journals, student portfolios, class listeners' essays for science class and analyzed qualitative data collected through constant comparison method. According to the result, we extracted 11 character elements and reorganized them into 16 specific character elements revealed in various learning situations based on the relationship between each character elements. The results of the study are eight specific character elements that can be emphasized through science learning and related learning situations. The eight specific character elements are 'responsibility for teaching behavior due to hierarchy of scientific knowledge structure, communication for forming scientific concept, empathic concern based on science learning experience, cooperation for promoting rationality of inquiry method, positive perception of scientific endeavor, respect for scientists' attitudes toward research, confidence in future scientific research, persistence in trial and error'. Based on the results of this study, we proposed the research methods of character in the field of science education in the future.

Vegetative Propagation and Morphological Characteristics of Amelanchier spp. with High Value as Fruit Tree for Landscaping (정원용 유실수로서 가치가 높은 채진목속(Amelanchier spp.)의 형태적 특성 및 영양번식방법)

  • Kang, Ho Chul;Hwang, Dae Yul;Ha, Yoo Mi
    • Journal of the Korean Institute of Landscape Architecture
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    • v.46 no.6
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    • pp.111-119
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    • 2018
  • This study was carried out to investigate the growth characteristics and propagation methods of the Korean native Amelanchier asiatica, A. arborea, and A. alnifolia as fruit trees for gardens. Due to the lack of recent research on Amelanchier spp., their superficial classification is still unclear and the names are being used interchangeably. The results are obtained as follows : A. arborea and A. alnifolia were globular type multi-stemmed shrubs. A 20-year-old tree of A. asiatica was 7.8m in height, with a 5.2m crown width, with one trunk. As for the morphological characteristics, leaves of A. asiatica were oblong, with an acuminate of, 6.1cm and 3.6cm width, but A. arborea and A. alnifolia had acute obovate leaves. The leaf size of A. alnifolia was the largest among the three species. The flower size of A. asiatica was bigger than that of A. arborea and A. alnifolia. In addition, its petals and flower clusters were also the largest among the three species. The flowering of A. asiatica initiated on April 21 and then bloomed for a duration of 24 days in Osan, while that of A. arborea and A. alnifolia initiated flowering on April 12 and then bloomed for a duration of 22 days in the same location. The fruit of A. arborea and A. alnifolia were green on May 10~12, it changed into purplish red on May 24~26, and its matured on June 1~3. The duration of fruit persistence of A. arborea and A. alnifolia were 48~50 days. On the other hand, A. asiatica showed greenish fruit on May 20, it became red on September 4, and had fallen by October 3. The fruit size was the largest at 1.03cm of height and 1.12cm of diameter in the A. arborea, followed by the big berry of A. alnifolia and the smallest fruit in the native, A. asiatica. It was difficult to root due to the hardwood cutting of A. arborea at a 40% rate of rooting. In the softwood cutting, the rooting rate of A. arborea was increased by the treatment with concentrated IBA, especially at 5,000 and 7,000ppm. The optimum date for cutting was on June 27, when the rooting rate was more than 80%. The most effective method for rooting of A. arborea was rootone or 7,000 ppm IBA treatment on June 27 softwood cuttings, which showed a rooting rate of over 80%.

Stage Structure and Population Persistence of Cypripedium japonicum Thunb., a Rare and Endangered Plants (희귀 및 멸종위기식물인 광릉요강꽃의 개체군 구조 및 지속성)

  • Lee, Dong-hyoung;Kim, So-dam;Kim, Hwi-min;Moon, Ae-Ra;Kim, Sang-Yong;Park, Byung-Bae;Son, Sung-won
    • Korean Journal of Environment and Ecology
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    • v.35 no.5
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    • pp.548-557
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    • 2021
  • Cypripedium japonicum Thunb. is an endemic plant in East Asia, distributed only in Korea, China, and Japan. At the global level, the IUCN Red List evaluates it as "Endangered Species (EN)," and at the national level in Korea, it is evaluated as "Critically Endangered Species (CR)." In this study, we investigated the characteristics of the age structure and the sustainability of the population based on the data obtained by demographic monitoring conducted for seven years in the natural habitat. C. japonicum habitats were observed in 7 regions of Korea (Pochoen, Gapyeong, Hwacheon, Chuncheon, Yeongdong, Muju, Gwangyang), and 4,356 individuals in 15 subpopulations were identified. The population size and structure differed from region to region, and artificial management had a very important effect on the size and structural change of the population. Population viability analysis (PVA) based on changes in the number of individuals of C. japonicum showed a very diverse tendency by region. And the probability of population extinction in the next 100 years was 0.00% for Pocheon, 10.90% for Gwangyang, 24.05% for Chuncheon, and 79.50% for Hwacheon. Since the above monitored study sites were located within the conservation shelters, which restricted access by humans, unauthorized collection of C. japonicum, the biggest threat to the species, was not reflected in the individual viability. So, the risk of extinction in Korea is expected to be significantly higher than that estimated in this study. Therefore, it is necessary to reflect population information in several regions that may represent various threats to determine the extinction risk of the C. japonicum population objectively. In the future, we should expand the demographic monitoring of the C. japonicum population known in Korea.

An Exploratory Study on the Business Failure Recovery Factors of Serial Entrepreneurs: Focusing on Small Business (연속 기업가의 사업 실패 회복요인에 관한 탐색적 연구: 소상공인을 중심으로)

  • Lee, Kyung Suk;Park, Joo Yeon;Sung, Chang Soo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.16 no.6
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    • pp.17-29
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    • 2021
  • Recently, as social distancing have been raised due to the re-spread of COVID-19, the number of serial entrepreneurs who are closing their business is rapidly increasing. Learning from failure is a source of success, but business failure can result in psychological and economic losses and negative emotions of the serial entrepreneur. At this point, it is very important to find a way to recover the negative emotions caused by business failures of serial entrepreneurs. Recently, a strategic model has emerged to deal with the negative emotions of grief caused by business failures of serial entrepreneurs. This study identified the recovery factors from the grief of business failures of serial entrepreneurs and analyzed Shepherd's(2003) three areas: loss orientation, restoration orientation, and dual process. To this end, individual in-depth interviews were conducted with 12 small business serial entrepreneurs who challenged re-startup to identify the attributes of recovery factors that were not identified with quantitative data. As a result of the study, first, recovery factors were investigated in three areas: individual orientation, family orientation, and network orientation. It was found to help improve recovery in nine categories: self-esteem, persistence, personal competence, hobbies, self-confidence, family support, networks, religion, and social support. Second, recovery obstacle factors were investigated in three areas: psychological, economic, and environmental factors. Nine categories including family, health, social network, business partner, competitor, partner, fund, external environment, and government policy were found to persist negative emotions. Third, the emotional processing process for grief was investigated in three areas: loss orientation, restoration orientation, and dual process. Ten categories such as family, partner support, social member support, government support, hobbies, networks, change of business field, moving, third-party perspective, and meditation were confirmed to enhance rapid recovery in the emotional processing process for grief. The implications of this study are as follows. The process of recovering from the grief caused by business failures of serial entrepreneurs was attempted by a qualitative study. By extending the theory of Shepherd(2003), This study can be applied to help with recovery research. In addition, conceptual models and propositions for future empirical research were presented, which can be discussed in carious academic ways.