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Effects of a Growth Retardant Paclobutrazol on the Growth and Yield Related Elements of Peanut (Archis hypogea L.) (생장조정제(生長調整劑) Paclobutrazol이 땅콩의 생육특성(生育特性)과 수량관련요소(收量關聯要素)에 미치는 영향(影響))

  • Lee, H.S.;Cho, J.S.
    • Korean Journal of Weed Science
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    • v.8 no.1
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    • pp.71-89
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    • 1988
  • This study was conducted to evaluate the effect of a growth retardant, Paclobutrazol on the growth, yield and its components. and physiological traits in peanut cv. Saeddle (early variety) and Nampung (medium variety). The results are summarized as follows : Main stem and branch length of both varieties were remarkably retarded at early growth stage application, but the retardation effect was reduced at late growth stage application. Number of branches was increased remarkably by treating 60ppm at 20days after seedling (DAS) in early variety. Lodging ill medium variety was not observed through growth period when 120ppm of Paclobutrazol was applied while lodging was not appeared between 40 DAS and 80 DAS in early variety. The numbers of riped pods in early variety was increased when application of 120ppm at 40 DAS was made while it was increased as application of 120ppm at 90 DAS in the medium variety. Cercospora leaf spot was reduced by spraying at 40 or 50 DAS regardless of concentration and varieties. Chlorophyll content and photosynthetic activity increased when paclobutrazol was applied during 40-60 DAS in early variety while these were observed at 90 DAS in medium variety. Seed weight tended to increase as paclobutrazol application was delayed. The ratio of pods to seeds was higher at 60ppm-40 DAS in early variety while it was higher at 120ppm-90 DAS in medium variety.

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Interpretation of Interaction of Herbicides on Principal Paddy Weeds - By Use of Oxyfluorfen and Bensulfuron-methyl Data - (주요(主要) 논 잡초종(雜草種)에 대한 제초제간(除草劑間)의 상호작용효과(相互作用效果) 해석연구(解析硏究) - Oxyfluorfen과 Bensulfuron을 예(例)로 -)

  • Han, J.H.;Guh, J.O.;Chon, S.U.;Kwon, O.D.
    • Korean Journal of Weed Science
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    • v.12 no.2
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    • pp.144-157
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    • 1992
  • The study was conducted to compare the interprete methods and examine the feasibility of mixture use of oxyfluorfen and bensulfuron in controlling principal Paddy weeds, annuals and perennials. Application ratio of both chemicals were obtained from the combinations of 5 levels(0, 5, 10, 15, 20 g ai/ha) of each chemicals, respectively. All the treatments were applied at 5 days after transplanting and water was maintained at 3.0cm in depth. Shoot fresh-weight of weeds was assessed at 35 days after treatments. Data obtained was analysed by Colby, Isobole, Calculus, Regression and EQM method, respectively. The results from the analysis of variance on the principal weeds treated with oxyfluorfen and bensulfuron showed significant interactions at 1% level on both Echinochloa crus-galli and Eleocharis Kuroguwai, and total species at 0.5% level on both Potamogeton distinctus and Cyperus serotinus, but non significant on Scirpus juncoides and Sagittaria pygmaea. Thereafter, the results of the models applied to Echinochloa crus-galli, Eleocharis kuroguwai and total species were as follows ; 1. The Colby method gave values nearly identical to regression estimate method (both multiplicative models) as provided by Akobundu et al. The Colby method and Regression method indicated synergistic toward Echinochloa curs-galli, and total species, but antagonistic toward Eleocharis kuroguwai. 2. The Isobole method shows synergism on Echinochloa crus-galli at $ID_{50}$, and total species at $ID_{60}$ on Eleochari kuroguwai. 3. The Calculus method gave positive signs for the first differentiation and negative signs for the second differentiation except for some rates on Echinochloa crus-galli and total species, but reverse on Eleocharis kuroguwai. These result does not agree with the observed values. 4. ${\theta}$ value from the EQM method was greater than one at all combinations. This result was quite different from those of other methods. 5. The various models did not show the same results, but mixture of oxyfluorfen and bensulfuron tend to have synergistic effect. Weeding effect also was high. Treatment in terms of two chemical combination was expected to reduce rates, and to enhence weeding efficacy compared with single treatment.

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Application Rate Modification of Paddy Herbicide Quinclorac Depending on Different Cultural Patterns (벼 작부양식(作付樣式)의 차이(差異)에 따른 제초제(除草劑) QUINCLORAC 의 선택활성(選擇活性) 변동(變動))

  • Guh, J.O.;Im, W.H.;Han, S.U.;Kuk, Y.I.
    • Korean Journal of Weed Science
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    • v.12 no.2
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    • pp.124-131
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    • 1992
  • Not only reducing the carry-over effects of quinclorac [3, 7-dichloro-8-quinoline carboxylic acid] used in paddy field to some following vegetable crops but also rationalizing agro-ecology conservation and farm economy, the reducing feasibility of application rates by various cropping patterns and application timing after rice seeding and transplanting. Four cropping patterns namely dry direct seeding(DDS), flooded direct seed(FDS), transplanting of 8 days old early seedlings(EST) and 25 days old machinery seedling(MST) were experimented with 7 application timings as 0, 5, 10, 15, 20, 25, 30 days after seeding/transplanting and 9 levels of application rates as 0, 75, 150, 225, 300, 375, 450, 525, and 600g ai/ha of the chemical, respectively. Within the maximum permitted limit of rice phytotoxicity, the minimum application rate of quinclorac to complete control of Echinochloa crus-galli as influenced by various cropping patterns with application timing could be evaluated as follows : A. Dry direct seeding : The minimized application rate at application timing upto 10 days after seeding (DAS) was counted 150g ai/ha, and delaying upto 15-30 DAS, the rates were increased upto 225-525g ai/ha. B. Flooded direct seeding and transplanting : The application rates were minimized 75g ai/ha at application timing upto 10 days after seeding/transplanting(DAS/T), 150g ai/haupto 15 DAS/T, and 225g ai/ha at later than 20 DAS/T, respectively.

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Development of Natural Antioxidants and Whitening Agents for Cosmeceuticals

  • Kim, Jong-Pyung
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2007.11a
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    • pp.79-92
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    • 2007
  • Oxidative stress have known to be a risk factor for the degenerative processes and closely related to a lot of diseases. It is well established that antioxidants are good in protection and therapeutic means against oxidative damage. There is increasing interest in natural antioxidants and many natural antioxidants have been found and utilized as the possible protection for various diseases and skin aging. We have screened natural antioxidant agents for cosmeceuticals, nutraceuticals, and drugs as therapeutic and preventive means against oxidative stress, and have developed a number of novel antioxidants from various natural sources. A novel melanin synthesis inhibitor, Melanocin A, isolated from the metabolite of a fungal strain Eupenicillium shearii F80695 inhibited mushroom tyrosinase and melanin biosynthesis of B16 melanoma cells with $IC_{50}$ value of 9.0 nM and MIC value of $0.9\;{\mu}M$, respectively. Melanocin A also exhibited potent antioxidant activity by scavenging of DPPH and superoxide anion radicals. UV was found to increase the level of hydrogen peroxides and other reactive oxygen species (ROS) in skin tissues. This increase in ROS may not only alter the structure and function of many genes and proteins directly but may also modulate their expressions through signal transduction pathways and, ultimately, lead to skin damage. We investigated the effect of Melanocin A on UV-induced premature skin aging. Firstly, the effect of Melanocin A on UV-induced matrix metalloproteinase (MMP)-9 expression in an immortalized human keratinocyte cell line, HaCaT in vitro was investigated. Acute UV irradiation induced MMP-9 expression at both the mRNA and protein levels and Melanocin A suppressed this expression in a dose-dependent manner. We then investigated UV-induced skin changes in hairless mice in vivo by Melanocin A. Chronic exposure of hairless mouse dorsal skin to UV increased skin thickness and induced wrinkle formation and the gelatinase activities of MMP-2 and MMP-9. Moreover, Melanocin A significantly suppressed UV-induced morphologic skin changes and MMP-2 and MMP-9 expression. These results show that Melanocin A can prevent the harmful effects of UV that lead to skin aging. Therefore, we suggest that Melanocin A should be viewed as a potential therapeutic agent for preventing and/or treating premature skin aging. Terrein is a bioactive fungal metabolite isolated from Penicillium species. Terrein has a relatively simple structure and can be easily synthesized. However, the biologic effects of terrein are comparatively unknown. We found for the first time that terrein potently inhibit melanin production in melanocytes and has a strong hypopigmentary effect in a spontaneously immortalized mouse melanocyte cell line, Mel-Ab. Treatment of Mel-Ab cells with terrein (10-100 mM) for 4 days significantly reduced melanin levels in a dose-dependent manner. In addition, terrein at the same concentration also reduced tyrosinase activity. We then investigated whether terrein influences the extracellular signal-regulated protein kinase (ERK) pathway and the expression of microphthalmia-associated transcription factor (MITF), which is required for tyrosinase expression. Terrein was found to induce sustained ERK activation and MITF down-regulation, and luciferase assays showed that terrein inhibits MITF promoter activity in a dose-dependent manner. To elucidate the correlation between ERK pathway activation and a decreased MITF transcriptional level, PD98059, a specific inhibitor of the ERK pathway, was applied before terrain treatment and found to abrogate the terrein-induced MITF attenuation. Terrein also reduced the tyrosinase protein level for at least 72 h. These results suggest that terrain reduces melanin synthesis by reducing tyrosinase production via ERK activation, and that this is followed by MITF down-regulation.

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A Study on Oxygen Reduction Reaction of PtM Electrocatalysts Synthesized by a Modified Polyol Process (수정된 폴리올 방법을 적용하여 합성한 PtM 촉매들의 산소환원반응성 연구)

  • Yang, Jongwon;Hyun, Kyuwhan;Chu, Cheunho;Kwon, Yongchai
    • Applied Chemistry for Engineering
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    • v.25 no.1
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    • pp.78-83
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    • 2014
  • In this research, we evaluated the performance and characteristics of carbon supported PtM (M = Ni and Y) alloy catalysts (PtM/Cs) synthesized by a modified polyol method. With the PtM/Cs employed as a catalyst for the oxygen reduction reaction (ORR) of cathodes in proton exchange membrane fuel cells (PEMFCs), their catalytic and ORR activities and electrical performance were investigated and compared with those of commercial Pt/C. Their particle sizes, particle distributions and electrochemically active surface areas (EAS) were measured by TEM and cyclic voltammetry (CV), while their ORR activity and electrical performance were explored using linear sweeping voltammetries with rotating disk electrodes and rotating ring-disk electrodes as well as PEMFC single cell tests. TEM and CV measurements show that PtM/Cs have the compatible particle size and EAS with Pt/C. When it comes to ORR activity, PtM/C showed the equivalent or better half-wave potential, kinetic current density, transferred electron number per oxygen molecule and $H_2O_2$ production(%) to or than commerical Pt/C. Based on results gained by the three electrode tests, when the PEMFC single cell tests were carried out, the current density measured at 0.6 V and maximum power density of PEMFC single cell adopting PtM/C catalysts were better than those adopting Pt/C catalyst. It is therefore concluded that PtM/C catalysts synthesized by modified polyol can result in the equivalent or better ORR catalytic capability and PEMFC performance to or than commercial Pt/C catalyst.

A Survey on the Status and Strategy of Swine Manure Utilization in the Gyeongnam (경남지역의 양돈분뇨 자원화 이용과 개선방안에 관한 실태조사)

  • Kim, D.H.;Shin, J.K.;Han, J.C.
    • Journal of Animal Environmental Science
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    • v.16 no.1
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    • pp.1-12
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    • 2010
  • This survey was conducted to investigate the status and strategy of swine manure utilization of 109 swine farms in the Gyeongnam, Korea. The personal properties of owner, types of swine buildings, facilities and equipment for manure management, conditions for manure recycling and farming for recycling resources were surveyed. Age of farm owners were occupied as 44.1% for 50s followed by the 60s with one-forth and 40s with 22.9%. Educational background of farm owners, a high school graduate makes up the largest proportion of farm owners followed by a college graduation with 35.8%. The swine manure collection methods were occupied as 34.9% with totally slurry system and more than 50% slurry system with 34.9% of farms. The manure management cost per ton were occupied as more than two-third with 10,000 won~15,000 won. The cost will pay for manure management, 10,000 won~15,000 won per ton makes up the largest proportion of farm owners. Separator, loader and vehicle to collection, transportation of liquid manure were occupied as 72.5%, 44% and 10.1%, respectively. Recognition of the farming for recycling resources were occupied as 37.6%, however, 25.8% of swine farm owners don't know that. More than sixty percent of swine farms will take a recycling system according to the farming for recycling resources. Conclusively, we have a suggestion in order to promotion of the farming for recycling resources in the Gyeongnam with increasing the portion of recycling of swine manure in each county and revitalizing the marketing of the liquid and solid swine manure fertilizers.

Assessment of Growth Conditions and Maintenance of Law-Protected Trees in Je-cheon City (제천시 보호수의 생육환경 및 관리현황 평가)

  • Yoon, Young-Han;Ju, Jin-Hee
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.28 no.2
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    • pp.67-74
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    • 2010
  • Law-protected trees are our precious asset as natural resources with history and tradition and natural heritage which should be protected and maintained well to bequeath next generation. Law-protected trees have not only thremmatologic and genetic meaning but also environmental and emotional meaning for their value to be high. This study investigated location, vitality, wrapping condition of root area and status of maintenance of the trees to figure out their growth environment and status of maintenance in a small-middle city through survey on those of law-protected trees in Je-cheon. There showed 300 more year old trees in Je-cheon mostly and the number of trees located in flat fields was the highest. For location type, village, hill and road types were presented in the order and for degree of development, land for building was found most frequently. The average electric resistance of the formative layer was measured to be $8.4k{\Omega}$ and four trees showed bark separation. Most law-protected trees underwent tree surgery, and complete bareness of root area was observed in a tree. The root area of two trees was covered with concrete. pH of soil was recorded to be 5.0~8.4 with its average of 7.1 and electric conductivity(EC) was less than 0.5 dS/m. For status of maintenance rearing facilities were placed for 16 trees out of totally 48 ones and stone fence was done for three ones. Tree surgery was conducted for 33 trees to prevent and to treat decomposed parts of holes. Direction boards were installed for 23 trees. Based on these results, measures to manage systematically law-protected trees in Jecheon could be suggested as follows. First, a sufficient space for growth of low part of trees should be secured. Second, a voluntary management should be induced by advertising them to residents in a community. Third, rearing facilities and direction boards of law-protected trees should be placed and related education should be conducted. Fourth, through operation of the department for law-protected trees consisting of related professions and cooperation among related departments the trees should be maintained continuously.

Optimal Lactic Acid Fermentation Conditions and Quality Properties for Rubus coreanus Miquel (Bokbunja) and Chlorella Mixtures (복분자와 클로렐라 혼합물의 젖산발효 최적조건 및 품질 특성)

  • Kim, Jae-Young;Lee, Sang-Uk;Kim, Na-Hyung;Moon, Kwang-Hyun;Baek, Seung-Hwa
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.3
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    • pp.386-395
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    • 2016
  • To develop a functional fermentation food from Rubus coreanus Miquel (Bokbunja) and chlorella mixtures, optimal lactic acid fermentation conditions were established, and quality properties based on physicochemical evaluation such as chemical compositions, free sugars, organic acids, and antibacterial activities were investigated. Regarding optimal fermentation strain selection, formation of lactic acid was best in Lactobacillus plantarum among the experimental strains (10 kinds), and the optimal fermentation temperature was $37^{\circ}C$. In addition, overall acceptability in the sensory evaluation was highest in the 5% chlorella mixture sample. Therefore, quality properties of the prepared sample under the established optimal fermentation conditions were investigated. Moisture, total sugar (dry basis), crude fiber (dry basis), and pH of fermented Rubus coreanus Miquel juice (RCM) with 5% chlorella mixture (RCM-C5) were reduced by 4.90%, 14.15%, and 0.32%, respectively, as compared with non-fermented RCM. Meanwhile, crude protein, crude fat, and crude ash (dry basis) of RCM-C5 were elevated by 13.75%, 0.18%, and 0.73%, respectively, as compared with RCM. The yellowness (b value) of color values was greater in RCM-C5 compared to RCM. The free sugar and organic acid contents of RCM-C5 were elevated by 0.97% and 616.30 mg%, respectively, as compared with RCM. In addition, the gram positive bacterium Staphylococcus aureus was elevated by 5.83% while gram negative bacteria Escherichia coli and Salmonella Typhimurium were elevated by 2.94% and 4.67%, respectively, as compared with RCM. In conclusion, the quality properties of RCM and chlorella lactic acid fermentation mixtures were improved compared with the general RCM product. Consequently, it is possible to apply fermented RCM as a functional fermentation food.

Rubric Development for Performance Evaluation of Middle School Home Economics - Focusing on Experiment and Practice Methods - (중학교 가정교과 수행평가를 위한 루브릭(rubric) 개발 - 실험.실습법에 적용 -)

  • Bum, Sun-Hwa;Chae, Jung-Hyun
    • Journal of Korean Home Economics Education Association
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    • v.20 no.3
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    • pp.85-105
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    • 2008
  • The purpose of this study was to develop a narrative analytic scoring rubric through teacher-students negotiations, as an assessment of tasks using methods of experiment and practice for home economic(HE) in the middle school. In this study. an analytic rubric had been developed in the following three stages: In the first stage, all the things for rubric development were defined and prepared, by selecting tasks used for rubric application through a questionnaire survey, providing detailed directions on methods and procedures and needed items, and selecting a class for rubric negotiation and setting the development schedule. In addition, the method suggested by Ainsworth and Christinson(1998) in Student Generated Rubrics was used. In the second stage, performance criteria for tasks in terms of knowledge, skills, and attitude were developed, setting scoring framework and scales depending on assessment areas. Referring to selected scoring framework and assessment criteria, observable and assessable behaviors were used to describe rubric based on A, B, and C scale. Then, a primary rubric was developed through teacher-students negotiations, using rubrics made by group. In the last stage, the developed primary rubric was reviewed by an expert of HE education to test the validity. Moreover, the analysis to test the suitability of the final rubric assessment tool employed 46 copies of questionnaire collected from incumbent home economics teachers selected by way of random sampling mainly focusing on those teachers who were in the Master's degree program or completed the program at one university. As a result, the average of suitability of aa the rubrics were over 4.0 in th 5-point scale.

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A Study on the Health Status of Dental Technicians by Todai Health Index(THI) (THI에 의한 일부 치과기공사의 건강상태에 관한 조사 연구)

  • Kwon, Soon-Suk;Moon, Hee-Jung;Shin, Myung-Suk;Kim, Yoon-Shin
    • Journal of dental hygiene science
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    • v.9 no.2
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    • pp.169-179
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    • 2009
  • This study aims to present a fundamental data base to figure out the mental and the physical conditions that the dental technicians are facing and ultimately to develop a health care program to deal with their health related problems. To this end, we took an analysis on the health status among the subjects of 895 dental technicians currently working at the dental lab around the nation from January 15 to March 31, 2009 by way or Todai Health Index(THI). Of the average scale point in accordance with 12 scale scores of the physical and the mental subjective symptom, the results revealed that the physical appeals (21.10) were higher than the mental appeals (18.49) and the multiple subjective symptom was marked as 38.44 followed by the mental irritability (25.92). In gender differences, the females proved to be higher than the males in both physical appeals and mental appeals while the physical appeals were dominant in both genders. The physical appeals were higher than the mental appeals with regard to the general characteristics. In the case or the group or age twenties as shown in the physical and mental average scale point, the other groups showed 21.55% of the physical appeals among the married whereas the mental appeals showed the highest point as 18.70 in the unmarried group. In job position, the other groups marked the highest, in working condition, below average group marked the highest, in frequency of break time, none group marked the highest. We drew a conclusion form this study that the dental technicians gained the higher points in the item or the multiple subjective symptom, the menial irritability, and the irregular life. More research on th is phenomena should be followed along with the development of various and practical health care programs to promote the health or dental technicians.

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