• Title/Summary/Keyword: Half Life

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The Shelf-life of Agricultural Organic Materials Containing Cinnamon or Derris Extract: Thermal Stability of Cinnamyl Derivatives and Rotenoids (계피 또는 데리스 추출물을 주원료로 하는 유기농업자재의 약효 성분 안정성)

  • Choi, Geun-Hyoung;Jin, Cho-Long;Park, Byung-Jun;Lim, Sung-Jin;Rho, Jin-Ho;Moon, Byung-Cheol;Kong, Seung-Heon;Kim, Jin Hyo
    • The Korean Journal of Pesticide Science
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    • v.20 no.3
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    • pp.197-202
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    • 2016
  • The stabilities of bioactive compounds in cinnamon or derris extract were investigated in commercial agricultural organic materials (biopesticide) during storage on different temperature conditions ($0^{\circ}C$, $23^{\circ}C$, $35^{\circ}C$, $45^{\circ}C$, and $54^{\circ}C$). The selected bioactive compounds were cinnamaldehyde, and cinnamyl alchol in cinnamon extract and deguelin, and rotenone in derris extract. Half-lives of the total cinnamyl derivatives in biopesticide (A, B, C, and D) ranged from 15.1 to 46.2 days on the different temperature and cinnamaldehyde was more stable than cinnamyl alcohol in the biopesticide. The half-lives of total rotenoid ranged from 1.7 to 173 days on the different temperature in the tested biopesticide (E, F, and G) containing derris extract. The stabilities of deguelin, and rotenon in the biopesticide showed similar values in the same condition.

Establishment of Pre-Harvest Residue Limits (PHRL) of Flubendiamide and Pyriofenone on Strawberry (Fragaria ananassa Duch.) (생산단계 잔류허용기준설정을 위한 Flubendiamide 및 Pyriofenone의 딸기(Fragaria ananassa Duch.) 중 경시적 잔류특성 연구)

  • Kim, Hee-Gon;Kim, Ji-Yoon;Hur, Kyung-Jin;Kwon, Chan-Hyeok;Hur, Jang Hyun
    • The Korean Journal of Pesticide Science
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    • v.21 no.1
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    • pp.62-67
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    • 2017
  • In this study, the residue patterns of flubendiamide and pyriofenone registered in the strawberry were investigated to predict pre-harvest residue limit (PHRL). The samples were harvested at 0, 1, 2, 3, 5, 7, 10 days after treatment and the pesticide residues were analyzed by HPLC/UVD. The limit of quantification (LOQ) was $0.01mg\;kg^{-1}$ for flubendiamide and pyriofenone. The recovery levels of flubendiamide and pyriofenone were $90.9{\pm}2.2%$ and $81.9{\pm}0.8%$, $87.7{\pm}2.1%$ and $85.3{\pm}1.1%$ for spiked levels of 0.01 and $0.1mg\;kg^{-1}$, respectively. The values of biological half-lives for field 1 and field 2 were 8.1 and 7.2 days for flubendiamide, 7.0 and 6.9 days for pyriofenone. According to these results, we recommends the level of PHRL on strawberry for flubendiamide and pyriofenone as 1.87 and $3.76mg\;kg^{-1}$ at 10 days before harvest, respectively.

Optimization of apical tip culture condition for In Vitro propagation of 'Gisela 5' dwarf cherry rootstock (양앵두 왜성대목 'Gisela 5'의 기내번식을 위한 정단배양조건의 최적화)

  • Xu, Junping;Kang, In-Kyu;Kim, Chang Kil;Han, Jeung-Sul;Choi, Cheol
    • Journal of Plant Biotechnology
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    • v.42 no.1
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    • pp.49-54
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    • 2015
  • Based on the results in this study, here we propose a systematic micropropagation process for 'Gisela 5' that is one of the important dwarfing cherry rootstocks. When the apical tips detached from newly developed shoot in spring season were cultured on the half strength MS media with 0.5 mg/L IBA and 0.5 ~ 1.0 mg/L BA, the cultures scored the highest acquisition rate at 90% for normal shoot with vigorous growth and without hyperhydricity. As next step, the young shoots maintained in vitro well multiplied on the full strength MS medium supplemented with 0.5 mg/L IBA and 0.5 mg/L BA, in which multiplication rate was approximately nine-fold. Given the half strength MS medium containing 2.0 mg/L IBA, each transplanted shoot further developed robust roots. Finally, the plantlets were easily acclimatized in the compost consisted of vermiculite, perlite, and peatmoss in the proportion of 1:1:1. We expect that the results are useful for cherry cultivation and its rootstock production.

A Study of Investigation about Improvement of Life Long Education for the Dental Technicians in Pusan (부산지역(釜山地域) 치과기공사(齒科技工士)의 보수교육(補修敎育) 개선(改選)에 관(關)한 조사연구(調査硏究))

  • Chung, In-Sung
    • Journal of Technologic Dentistry
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    • v.12 no.1
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    • pp.73-93
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    • 1990
  • The study objected to the 120 persons out of 360 persons who have registered under the association of the dental technicians in Pusan to grasp contents about improvement of life long education of the present day of November, 1987, and its results, which we have acquired by this study were as follows : 1. A sense of satisfaction toward the system of life long education appeared as unsatisfaction and its unsatisfaction decreased from the rate of member's attendance or exam. marks, the contents of education, and place of education. 2. The problem of the exam. mark which derived by the presence by the substitute appeared which 46.7 percent(56 persons), lack of opportunity for the recompletion at branch association appeared which 19.2%(23 persons), given 4. exam. marks at the over all scientific contest was appeared 14.2 percent(17 persons), relation which legal treatment when ones didn't completed exam. mark was appeared 10.8 percent(13 persons) and lastly, appeared 8.3 percent (10 persons) with time of delivery of the exam mark card. 3. The frequency of the opening for the life long education which related with the rate of members attendance was fixed as nowadays two times per annually, but they perferred the opening per academic blanch once out of the firest half year and the latter half of the year and, they liked the openings at the first week or second week and preferred the holding on saturdays and sundays. 4. The subject of the life long education have appeared the opinion that the thesis was lop-sided toward the allocation of time schedule of lecture appeared the opinion of which they perferred the rate of an hour of cultural subject and two hours of major studies, and invitation for an instructor they preferred one dentist, one member, one dean for the cultural subject, and there are lots of opinions which they wished display of materials. 5. A sence of satisfaction about the place they perferred was decreased such as ; an auditorium concerned of the colleges was 46.7 Percent(56 Persons), hotels 26.7 Percent(32 Persons), an auditorium of the general hospital 20 percent(24 persons) 6. And lastly, there are lots of opinions who have required the necessities to constitute for the academic branch.

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Differences between Male and Female in Moving Motivation and Life Satisfaction of Senior Cohousing Residents in Scandinavia (스칸디나비아 노인용 코하우징 주민의 이주동기와 생활만족도의 성별 차이)

  • Choi Jung-Shin;Cho Jae-Soon
    • Journal of Families and Better Life
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    • v.24 no.1 s.79
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    • pp.117-128
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    • 2006
  • The purpose of this research was to find out the differences in the moving motivation and life satisfaction of senior cohousing communities between male and female residents in Scandinavia, especially in Sweden and Denmark. Senior cohousing is an attractive housing alternative for the aged 55 and over who looks for sharing one's life with neighbors. The 655 survey questionnaires out of 960 had replied from 14 Seniorbofrellesskaber in Denmark and 11 seniorhus within SABO sector and 8 housing cooperatives initiated by the Seniorgarden Housing Company in Sweden during April to May, 2002. The data were analyzed by SPSS win program, using frequencies, percentiles, cross-tabulations, and Pearson's correlations. The results showed that the senior cohousing residents were generally healthy and age of 70's years old and nearly half lived with a spouse. The male residents lived with a spouse about 2 times more than did the female. The residents had very strong motivation to move into the community and very high life satisfaction. Most aspects of moving motivation were not differed by the sex of the residents. However, male residents were more likely than female to be motivated to move in by becoming a pensioner, while female residents were more likely than male to be motivated by being a widow, looking for safety, or avoiding loneliness. These different motivation to move in by sex become more clear when general characteristics such as age, health status, living with or without a spouse, or country were controlled. Female residents were more likely than male to live' dream life' in the senior cohousing community. The stronger the moving motivation, the higher the life satisfaction in the community.

Changes in Extraction Efficiency of Pine Needles depending on Extraction Method and the Condition (추출 방법과 조건에 따른 소나무 지엽 추출효율 변화)

  • Kim, Dong Sung;Kim, Hyung Min;Sung, Yong Joo;Kang, Seog Goo;Kang, Ho-Yang;Lee, Jun-Woo;Kim, Se Bin;Park, Gwan-Soo
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.48 no.1
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    • pp.93-99
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    • 2016
  • The extraction efficiency depending on the extracting methods and the conditions of extraction was investigated. The common steam extraction was compared to the distillation extraction method. The effects of the samples size and the extraction time on the extract yield were also investigated by using UV-Vis spectrophotometer. One of the functional components of pine needle extract as the natural phenol base components were detected by the UV-VIS at around 235 nm wavelength range. The absorbance intensity at around 235 nm wavelength of the pine needle extract was used as the indicator of the extraction efficiency in this experiment. The distillation extraction showed the higher extract yield than the steam extraction. The grinding treatment of pine needles also resulted in the better extract performance, but the severe grinding showed a little decrease in the extract yield especially in case of the distillation extraction method. More than half of the extract was collected at the first stage of the extraction, that was the first 15 minutes in the total 60 minutes extraction.

The Impact of Information Technology Investment on Cost Reduction in Korean Insurance Industry (한국 생명보험산업의 정보화투자와 비용절감)

  • Lee Young-Soo;Jung Kun-Oh
    • Journal of Korea Technology Innovation Society
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    • v.9 no.1
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    • pp.175-198
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    • 2006
  • Analyzing the effects of information technology(IT) in the life insurance Industry is important in establishing the direction for future information technology investment. In this research, the cost-elasticity of IT capital stock was measured by the SUR technique, using the second-order translog cost function, which was drawn out by a Taylor expansion of the multi-product joint cost function. Analysis was made based on data from 1991 to 2003 collected from 33 life insurance firms. The results show that although the effects of information technology investment vary according to individual life insurance firms, half of the life insurance firms surveyed reduced their costs by investing in information technology. The research also revealed that although large life insurance firms reduced their costs by investing in information technology medium & small life insurance firms and foreign ,life insurance firms increase their costs. Additionally, although both information capital and information labor increase as the information budget increases, the increase in information capital is larger than one in information labor. Because the price of information capital is decreased rapidly more than one of information-related labor.

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Predictors of life satisfaction in marriage migrant wives with school-aged children (학령기 자녀가 있는 결혼이민자 여성의 생활만족도 예측 변인)

  • Sung, Miai;Choi, Yeojean
    • Journal of Family Resource Management and Policy Review
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    • v.21 no.1
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    • pp.1-18
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    • 2017
  • This study examined the predictors of life satisfaction of marriage migrant wives with school-aged children in South Korea. For this purpose, we draw data from the 2015 National Survey on Multi-cultural Families (NSMF). The target group was marriage migrant wives who were in a first marriage and had school-aged children (N=3,004). We used OLS regression to examine the predictors of the target group's life satisfaction with the SPSS 18.0 program. The results are as follows. First, marriage migrant wives with school-aged children had maintained their marriage for at least 14 years. They were satisfied with their relationships with both their spouses and their children. Also, they were satisfied with their spouse's child care roles. They did not support the multi-cultural policy of assimilation. Their Korean proficiency was slightly higher than the middle level. More than half had jobs and had not attended a parent meeting. Second, although they were satisfied with their everyday lives, their levels of life satisfaction were less than that of migrant wives with children below 5 years of age. Third, all variables explained 38.8% of the life satisfaction experienced by marriage migrant wives with school-aged children. Satisfaction with their spouses, subjective health, satisfaction of spouse's child care role, monthly family income, satisfaction with their children, experience attending a parents meeting, and Korean proficiency were positively associated with the life satisfaction of this target group. The findings of this study are significant because they can provide certain implications for family life education and policy within a multi-cultural society.

Prediction of Fatigue Life in 2 Ply Rubber/Cord Laminate (2층 고무/코드 적층판의 피로 수명 예측)

  • 임동진;이윤기;윤희석;김민호
    • Composites Research
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    • v.16 no.3
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    • pp.9-17
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    • 2003
  • In order to simulate the crack connection between cords and the interply crack growth in the belt-layer of real tire, 2 ply rubber/cord laminate specimens with exposed edges were tested in 4~11mm displacement control. Measurement of the crack connection is evaluated when crack reaches the half of the length between 45$^{\circ}$ aligned cords, and the amount of the crack growth is measured by the steel probe method. 2 dimensional analytic modeling was performed to simulate the crack connection between cords at the exposed edges. Also, the theoretical life of the specimens was calculated from the crack connection life between cords(critical value) and from the critical value to the final failure by the use of Tearing energy(T); the strain energy release per unit area of one fracture surface of a crack. Then, theoretical life was compared with those of experiments. The life prediction up to the critical value has about 20% error compared to experimental life, and up to the final failure about 65% error. Therefore, total theoretical life has about 45% error compared to the experimental life, which is conceivable in the case of rubber.

Establishment of an analytical method for butaphosphan (BTP), a stress-attenuating agent, and its application in the preliminary pharmacokinetic evaluation of residues in olive flounder Paralichthys olivaceus

  • Lee, Ji-Hoon;Bae, Jun Sung;Lee, Chae Won;Yang, Chan Yeong;Choi, Ji-Sung;Choi, Sang-Hoon;Kang, Yue-Jai;Park, Kwan Ha
    • Fisheries and Aquatic Sciences
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    • v.23 no.4
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    • pp.10.1-10.10
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    • 2020
  • Background: Butaphosphan (BTP) has recently been introduced into the Korean aquaculture sector as a stressattenuating agent. In this study, a sensitive chemical analytical method was established for the detection of BTP in the olive flounder (Paralichthys olivaceus) tissues. Methods: Utilizing a method employing liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), detection sensitivity, specificity, and precision were satisfactorily established. Temporal changes in the BTP plasma and muscle concentrations were assessed after a single intramuscular injection of BTP (50 and 150 mg/kg) to the olive flounder maintained at 13 ℃ or 22 ℃. Results: High BTP plasma levels were achieved immediately after the injection, and the drug was rapidly eliminated. Additionally, plasma BTP levels were markedly dependent on the elimination rate, which, in turn, seemed dependent on the water temperature, with the drug elimination half-life and mean residence time significantly shorter at 22 ℃ than 13 ℃. Overall, muscle BTP levels were markedly lower than the plasma levels. Notably, muscle levels were not influenced by water temperatures. Muscle BTP concentrations were used to estimate the necessary withdrawal period for drugs used in food fish, with BTP levels maintained far below the possible hazardous limit. Conclusions: In conclusion, the established LC-MS/MS method can be used for BTP residue detection with high sensitivity and reproducibility.