• Title/Summary/Keyword: retention level

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Influence of Copper Azole Retention Level to Wood Decay (목재 내 Copper Azole 보유량이 목재부후에 미치는 영향)

  • Lee, Hyun-Mi;Son, Dong-Won;Lee, Han-Sol;Hwang, Won-Joung
    • Journal of the Korean Wood Science and Technology
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    • v.43 no.1
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    • pp.112-121
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    • 2015
  • In this study, Copper Azole (CuAz), a domestically available wood preservative for pressure treatment, was employed to perform an experimental research on its infiltration and decay properties in Japanese Red Pine. Test specimens were pressure-injected with CuAz-2 preservative to measure its preservative effectiveness, and then its impact on weight and mass losses. Furthermore, wood specimens were treated with CuAz-2 preservatives of various concentration levels before they were decayed with brown-rot-fungi in order to observe decay properties on light microscope (LM) and field emission scanning electron microscope (FE-SEM). As a result, untreated specimen by Fomitopsis palustris showed the mass loss of more than 40%, and the value of preservative effectiveness of CuAz-2 by indoor decay was $1,73-3.32kg/m^3$. The concentration levels of CuAz-2 preservative were shown to cause significant variations in terms of decay progresses in the cross section, radial section, and tangential section. By contrast, untreated specimens had underwent serious decays in early wood, late wood, longitudinal resin canals, and ray, which led to vertical destruction of wood texture. As for the radial section, ray tracheid, ray parenchyma cell, and window like pits were decayed and destroyed. In the case of tangential section, uniseriate rays and vertical resin canals were seriously decayed. In conclusion, this study indicates that the adequacy of the current CuAz injection amount should be reviewed in the domestic environment because there are significantly different decays at different decay conditions.

Effect of Dietary Supplementation of Vitamin A or β-Carotene on Oxidative Damage Induced by Acute Ethanol Administration in Rats (비타민 A와 β-Carotene의 급여가 에탄올의 급성 투여에 의한 흰쥐의 산화적 손상에 미치는 영향)

  • 장정현;양경미;서정숙
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.1
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    • pp.81-86
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    • 2002
  • The present study was conducted to investigate the effect of dietary supplementation of vitamin A or $\beta$-carotene on oxidative damage induced by acute ethanol administration. Sprague-Dawley rats were fed on the experimental diets supplemented with retinyl acetate (2.86 mg/kg diet) or $\beta$-carotene (15.2 mg/kg diet) for 5 weeks. After fed the diet, rats were administered 20% ethanol solution (3g/kg B.W.) acutely. Lipid peroxide values in hepatic tissue, hepatic antioxidative enzyme activities and contents of antioxidative nutrient such as vitamins A and E in serum and hepatic tissue were measured. Hepatic level of malondialdehyde decreased in $\beta$-carotene group compared to the control group. However, there was no significant difference between retinal acetate and $\beta$-carotene groups. Superoxide dismutase activity was higher in retinal acetate group than in the control group. Hepatic glutathione-S-transferase activity of retinal acetate and $\beta$-carotene groups significantly decreased as compared with that of control group. The hepatic content of retinol increased in retinal acetate and $\beta$-carotene groups, especially, in retinyl acetate group. But there was no significant difference in serum content of retinol among the groups. Hepatic content of $\alpha$-tocopherol was significantly increased in retinyl acetate and $\beta$-carotene groups. In conclusion, acute ethanol administration might induce lipid peroxidation, and the dietary supplementation of retinyl acetate or $\beta$-carotene improve partly the antioxidative system through activation of superoxide dismutase and retention of hepatic $\alpha$-tocopherol in ethanol-treated rats.

Effects of Disinfectant Concentration, pH, Temperature, Ammonia, and Suspended Solids on the Chlorine Disinfection of Combined Sewer Overflow (소독제 농도, pH, 온도, 암모니아 농도, 부유물질이 강우 월류수 염소 소독에 미치는 영향)

  • Kim, Sang-Hyoun
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.10
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    • pp.685-690
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    • 2014
  • The treatment of combined sewer overflow (CSO) is one of potential concerns in domestic wastewater treatment in Korea due to the pre-announce of CSO regulations. This work investigated the effects of disinfectant (NaOCl) concentration (0.11 to 4.0 mg $Cl_2/L$), pH (6.5 to 8.0), temperature (15 to $25^{\circ}C$), ammonia (10 to 41 mg N/L), and suspended solids (91 to 271 mg SS/L) on the chlorine disinfection of CSO. The effect of NaOCl concentration on the pseudo-$1^{st}$ order reaction rate for total coliform inactivation was described well with a saturation-type model with the half-velocity constant of 1.212 mg/L. The total coliform inactivation reaction rate decreased with SS and pH, and increased with temperature. Ammonia in the examined range did not affect the disinfection kinetics. A chlorine contact tank with the injection chlorine level of 1 mg $Cl_2/L$ and the hydraulic retention time of 1.25 min is estimated to reduce total coliform from $1{\times}10^5MPN/mL$ to 1,000 MPN/mL at 271 mg SS/L, $15^{\circ}C$, and pH 8.0. Chlorine would be a proper option for the disinfection of CSO.

Body Weight Changes and Lifestyle in Women within 1 year after Childbirth (여성의 출산 후 체중변화와 생활양식)

  • Chung, Chae Weon;Kim, Hyewon;Kim, Hyojung
    • Perspectives in Nursing Science
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    • v.13 no.2
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    • pp.88-95
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    • 2016
  • Purpose: Gestational weight gain and prepregnancy body weight are important factors of childbirth outcomes, which further cause obesity, metabolic diseases, or psychological problems later in women's lives. Changes in diet, westernized lifestyle, traditional postpartum care, and childbirth at older age are thought to be threats to proper weight management in Korean women of reproductive age. Public health and antenatal care need to focus on the proper body weight management of women by carefully planning pregnancy to postpartum periods. Purpose: This study explored the body weight changes from pregnancy to postpartum and the related characteristics in women within 12 months after childbirth. Methods: A cross-sectional, retrospective study was conducted with 102 Korean women within 12 months after childbirth. Data were collected using an online survey system, and a structured questionnaire available for electronic self-administration was modified to include demographics, obstetrical history, and body weight at 6 time points. The International Physical Activity Questionnaire and Eating Habit Measurement instruments were also used in data collection. A professional survey agency recruited the participants, and data were automatically saved and then analyzed. Results: The average age of the participants was 33.8 years, 48% were housewives and were well-educated. Seventy-two percent of the participants were primiparas and 82% had breastfed their babies. The body mass index (BMI) ranged from 17.3 to 27.8, indicating that 21.5% of the participants were overweight or obese. The mean gestational weight gain was 11.8 kg, and weight loss was apparent during the first 3 months postpartum. The mean decline in weight was 3.4 kg at one year after childbirth. Women wanted to lose 5.6 kg (range: 3~20 kg), however 44% of them reported that they had not engaged in any weight control efforts. Further, 72% of them reported having engaged in a low level of physical activity. Body weight was not associated with women's characteristics, physical activity score, and diet. Conclusion: Women's awareness of gestational weight gain, lifestyle modification, and the risk of prolonged weight retention should be promoted through the antenatal and women's healthcare systems. As pregnancy and childbirth are critical events that affect women's health, integrative education to ensure healthy transition to life after delivery is required.

The Causal Relationship among Vision-sharing, Communication, Management Competences and Performance of Agricultural Product Unit in Rural Village Level (마을단위 농업경영체의 비전공유, 의사결정과정, 실무경영역량과 경영성과와의 관계)

  • Park, Un Sun;Park, Joo Sub;Jo, Hyung Rae;Lee, Sang Young
    • Journal of Agricultural Extension & Community Development
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    • v.20 no.1
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    • pp.105-141
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    • 2013
  • This study focuses on the vision-sharing practices, actual management capabilities and marketing competence for management which are supposed to be associated with the performance of village-based agricultural production sector. For this, vast literatures related to this issues were reviewed and analyzed. and which were used to establishment of research model. And then questionnaire were developed along the research model, survey were implemented using the questionnaire. In survey both of questionnaire and interview were used to obtain proper opinion. Total of 51 completed questionnaires were obtained and used to empirical analysis. The correlation method was used to investigate the relationships between factors affecting performance of agricultural production unit and performance. Major findings are as follows: (1) in overall, factors related to the vision-sharing or communication are not so important or even negative effects on the performance (2) in overall, factors of management competences are relatively associated with the performances positively (3) in overall, general management capabilities like planning or analyzing were positively related to the performance (4)significant factors which were related to the positive effects on the performances were alternatives considering risk of depreciation, securing stable customers, retention of professional personnels.

Effect of 1-MCP and High $pCO_2$ Treatment on the Firmness and Pectin Changes in Peach(Prunus persica) Fruit During Shelf-life (1-Methylcyclopropene(1-MCP) 및 $CO_2$ 처리가 복숭아(Prunus persica) 과실의 경도와 세포벽 변화에 미치는 영향)

  • Kim, Myun-Surn;Min, Jeong-Ho;Chun, Jong-Pil;Kim, Jin-Guk;Lee, Eun-Mo;Lee, Ji-Yong;Hwang, Yong-Soo
    • Korean Journal of Agricultural Science
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    • v.37 no.2
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    • pp.209-216
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    • 2010
  • In order to understand the effects of a single or combined treatments of 1-MCP($1{\mu}L/L$) and $CO_2$(100%) on the firmness of melting type peach fruit(cv. Chunjungdo), fruit were harvested at commercial maturity and examined physiological changes including flesh firmness during 10 days of shelf-life. Firmness loss of fruit was delayed by both single and combined treatments of 1-MCP and $CO_2$. The treatment of 1-MCP was more effective than $CO_2$ treatment but no additive effective on firmness retention was found in the combined treatment. The upsurge of ethylene evolution occurred 5 days of shelf-life in air treated control but ethylene evolution gradually increased in fruit treated by 1-MCP and 1-MCP+$CO_2$. The suppression of ethylene evolution seemed stronger in $CO_2$ treatment. The respiration of fruit significantly inhibited up to 10 days except control where climacteric increase of respiration was found at 10 days of shelf-life. A molecular shift of pectic polymers(an increase of chelator soluble pectins and decrease of water soluble pectins) was induced by both 1-MCP and $CO_2$ treatments. An increase of water soluble pectins was coincident with firmness loss. The delay of firmness loss seemed to be associated with the migration of calcium to wall matrix, especially pectins, resulting in the increase of wall bound calcium. The polygalacturonase activity was significantly reduced by 1-MCP alone 1 day after treatment and increased to similar level of activity 5 days after treatment compared to other treatment except air treated control whereas pectin methylesterase activity seemed not to be affected by both 1-MCP and $CO_2$ treatments. Thus, the molecular shift of pectic polymers appeared not to be related with pectin methylesterase. Further study is required to clarify the softening mechanism associated with molecular shift of pectic polymers and the inter- or intra-cellular movement of calcium ions induced by postharvest treatments of 1-MCP and $CO_2$.

Simultaneous Determination of Heavy Metals in Cosmetic Products by Ion Chromatography (이온 크로마토그래피를 이용한 화장품 중 중금속 동시분석)

  • Lee, So-Mi;Jeong, Hye-Jin;Kim, Han-Kon
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.34 no.1
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    • pp.57-62
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    • 2008
  • No matter how small amount of heavy metals it may be cause skin allergies through percutaneous adsorption when existing in cosmetic products as impurities. In order to develop a highly sensitive method for simultaneous determination of $Pb^{2+},\;Fe^{2+},\;Cu^{2+},\;Ni^{2+},\;Zn^{2+},\;Co^{2+},\;Cd^{2+},\;and\;Mn^{2+}$ in coloring agents and cosmetic products with rapidity and accuracy, we carried out the determination on ion chromatography. All of these metals are well separated through a bifunctional ion-exchange column(IonPac CS5A) and detected by post-column reaction and spectrophotometric detection. The calibration graphs are linear($r^2>0.999$) in the range $0.1{\sim}1000{\mu}g/mL$. Detection limits for 200 ${\mu}L$ of sample solution are at the level of ${\mu}g/L$, which is sufficient for judging whether the product is safe or not. The relative standard deviations(RSDs) of the retention time and the peak area are less than 0.21 and 1.24%, respectively. The recovery rates are $97{\sim}104%$. The new method was applied to analyze the amount of heavy metals which were contained in 22 cosmetic products and 11 coloring agents.

Effect of Unexpected Foaming Incident on Nitrogen Removal in a Vertical Subsurface Wetland (수직지하 흐름형 습지에서 거품발생이 질소제거에 미치는 영향)

  • Cheng, Jing;Guerra, Heidi B.;Kim, Youngchul
    • Journal of Wetlands Research
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    • v.21 no.4
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    • pp.334-343
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    • 2019
  • A lab-scale vertical flow subsurface (VFS) wetland composed of three parallel columns with polypropylene synthetic fiber as main substrate was operated. Piggery stormwater diluted from swine excreta was fed to the wetland on the basis of three different hydraulic regimes or hydraulic retention time (HRT) of 2, 4, and 8 days with daily internal recirculation. Then, monitoring of common water quality parameters was carried out. Unexpectedly, an increase of effluent COD concentration accompanying the appearance of foams was observed during a distinct period in the wetland with HRT 2, 4, and 8 days, successively. Subsequently, a series of experiments was conducted to investigate the origin of the foams. Foams and the increase of COD concentration were found to be induced by the release of organic matter from the synthetic polypropylene fiber which was fed with piggery stormwater. Meanwhile, nitrogen removal was found to be enhanced during a period which overlapped the distinct foaming period signifying that foaming played two important functions in biological nitrogen removal. Foams which form rapidly and then burst easily could hold up and then release oxygen for nitrification. Foams which contain organic surfactants could serve as carbon sources for denitrification as well. Hence, nitrogen removal was enhanced during the foaming stage. After that, COD concentration decreased slowly to a level prior to the foaming stage, and nitrogen removal efficiency declined as well.

Effect of Different Processes on Texture of Fermented Cucumber Pickles (열처리조건이 오이지의 질감에 미치는 영향)

  • Yoon, Sun;Lee, Jin-Sil;Hong, Wan-Soo
    • Journal of the Korean Society of Food Culture
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    • v.4 no.1
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    • pp.103-108
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    • 1989
  • Effects of different processes or texture of cucumber pickles fermented in 7% NaCl solution were studied. Cucumbers were treated with different processes: control; preheating in 7% NaCl, 0.04M $CaCl_2$ solution ($60^{\circ}C$, 1hr); combination of preheating and post microwave heating (5 min, midium high level, 2450 Mhz); preheating in the solution which was adjusted to pH 8.5. In each process the pH and total acidity of brine solution, total pectin contents in alcohol insoluble solids (AIS), hot water soluble pectin (HWSP) contents and firmness of cucumber pickles were determined at 0, 5, 10, 15 and 25 days of storage periods. Total pectin contents and the firmness of pickles were decreased during 25 days of storage. Control group showed the lowest value and post microwave heating group marked the highest value in total pectin contents and firmness retention of cucumber pickles. The results of this study indicated that total pectin content seems to correlate with the firmness of cucumber pickles. However, HWSP content did not show any correlation with firmness of cucumber pickles. Post microwave heating method could be used to retain firmness of fermented cucumber pickles.

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A Cross-Cultural Investigation on the Effects of Physical Environment at University Dormitory on Social Interaction among Students (문화적 배경에 따른 대학기숙사 물리적 환경이 학생들간 사회적 교류에 미치는 영향 비교연구)

  • Kim, Wonpil
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.8
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    • pp.48-54
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    • 2017
  • University dormitories play an important role in both the campus experience and academic achievement, as well as providing the students with their basic necessities. Further, there is a high demand to increase the capacity in order to raise the retention rate and to invite more foreign students. Students' social interaction and sense of community (SOC) also play an important role in reducing the stress associated with studying and home sickness and, consequently,the campus is a place that provides positive opportunities for their personal growth and adaptation into their peer group social culture. The purpose of this study is to investigate the effects of the physical environment of the dormitory facilities on the students' sense of community and social interaction in across-cultural background.The ${\chi}^2$ analysis indicated that individual characteristics exist regarding SOC, however, there were no statistically significant differences between the two cultural groups. The factors of SOC and physical environment were higher in the Korean student group than in the U.S. group. The regression analysis indicated that the U.S. students considered a physically comfortable environment as the primary issue for social interaction, while the Korean group placed more emphasis on a family-oriented home environment. The linear analysis confirmed that satisfaction with the physical environment influenced the social interaction and SOC level. Finally, this study suggests that creating a homely environment is more important than the functioning of the institution in university dormitory planning.