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Epidemiological Studies of Clonorchiasis - II. Current Status and Natural Transition of the Endemicity of Clonorchis sinensis in Goyang Gun, a Low Endemic Area in Korea (간흡충증(肝吸虫症) 역학(疫學) - II. 저도유행지(低度流行地) 고양지방(高陽地方)에 있어서의 간흡충감염(肝吸虫感染)의 현황(現況)과 자연추이(自然推移))

  • Kim, D.C.;Lee, O.Y.;Lee, J.S.;Ahn, J.S.;Chang, Y.M.;Son, S.C.;See, S.H.
    • Journal of agricultural medicine and community health
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    • v.8 no.1
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    • pp.66-80
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    • 1983
  • As a part of the epidemiological studies of clonorchiasis in Korea, this study was conducted to evaluate the current endemicity and the natural transition of the Clonorchis infection in Goyang Gun a low endemic area in recent years, prior to the introduction of praziquantel which will eventually influence to the status of the prevalence. The data obtained in this study in 1983 were evaluated for natural transition of the infection in comparison with those obtained 16 years ago in 1967 by the author (Kim, 1974). The areas of investigation, villages and schools surveyed, methods and techniques used in this study were the same as in 1967, except for the contents of the questionnaire for raw freshwater fish consumption by the local inhabitants. 1) The current prevalence rate of Clonorchis infection among the inhabitants was 7.5% on the average out of a total of 479 persons examined. The prevalence rate was 9.0% in the riverside area and 4.2% in the inland area. Among the schoolchildren, the prevalence rate was 1.1% out of a total of 1 319 examined. By area, it was 1.4% in the riverside area and 0.7% in the inland area. By sex, the prevalence rate was 13.3% in the male and 1.3% in the female in the inhabitants and no difference was seen in the schoolchildren. 2) In the natural transition of the infection, the prevalence rate in the inhabitants has decreased from 22.5% in 1967 to 7.5% in 1983, and in the schoolchildren, from 9.5% in 1967 to 1.1% in 1983. The reduction rate was higher in the riverside area than in the inland area. 3) In the prevalence rate by age, 1.2% was seen in the 10-14 age group and gradually increased to 8.1% in the 30-39 age group and reached peak 18.1% in the 40-49 age group. By sex, in the male, the prevalence rates have increased to 31.9% and 33.3% in the 40-49 and 50-59 age groups, respectively and decreased thereafter. In the female, the prevalence rate less than 5% was seen only in between the 10-14 and 30-39 age groups. 4) In the natural transition of the prevalence rate by age, sharp decrease was seen in the male from around 50% in 1967 between 15-19 and 30-39 age groups. The generation over 40s showed less decrease. In the female, the prevalence rate has decreased from 13% in 1967 to 5% in 1983 in the middle age groups and dropped to 0% in the rest of the age groups. 5) The intensity of the infection among clonorchiasis cases by mean EPmg (number of eggs per mg feces) value was 1.4. In the inhabitants, the value was 2.0 in the riverside area and 0.4 in the inland area. While in the schoolchildren, the value was 0.2 in both riverside and inland areas. 6) In the transition of the intensity of the infection, EPmg among the inhabitants has decreased from 3.9 in 1967 to 2.0 in 1983 in the riverside area, and from 2.9 to 0.4 in the inland area. In the schoolchildren, the reduction was similar in both riverside and inland areas resulting from 1.0-1.1 in 1967 to 0.2 in 1983. 7) In the intensity of the infection by age, EPmg 3.4 was peak at the 40-49 age group and 0.2-1.0 was seen in the rest of the age groups. The mean value was 1.5 in the male and 0.6 in the female. 8) In the natural transition of the intensity of the infection, the EPmg has decreased from 2.7 in 1967 to 1.4 in 1983. By age, reduction was seen in all of the age groups, particularly in the young and the old age groups of 50s and over, except in the 40-49 age group in which reverse phenomenon was seen. By sex, it has decreased from 3.5 in 1967 to 1.5 in 1983 in the male and from 1.0 to 0.6 in the female. 9) In the distribution of the clonorchiasis cases by the range of EPmg value, 70.3% of the cases were placed in the range of 0.1-0.9 as the most and 16.2% in 1.0-4.9 as the next. With such figures, those included in the range less than 0.9 as light infection were 78.4% and under 5.0-9.9 up to moderate infection 99.3% of the cases were covered. The cases were distributed up to 20.0-39.9 in the male and to 1.0-4.9 in the female. 10) In the transition of the distribution of the clonorchiasis cases by EPmg, the highest intensity reached up to 60.0-79.9 in 1967 and to 20.0-39.9 in 1983. In the range of light infection, under 0.1-0.9, the distribution in rate was 64.5% in 1967 and 78.4% in 1983. Up to the range of moderate infection, under 5.0-9.9, 91.7% in 1967 and 97.3% in 1983 were seen respectively. 11) In a survey for raw freshwater fish consumption among the local inhabitants,78.3 of the clonorchiasis cases interviewed admitted their experience of the raw consumption. However, those who practised in the past two years were 34.8% 55.6% of those who have such experience in the past professed that they did not practise raw freshwater fish consumption in the past two years. 12) The major cause of the reduction of the raw freshwater fish consumption among the inhabitants were the wide spread water pollution in the locality. The most common reason professed for stopping raw freshwater fish consumption among the inhabitants was the risk of the fluke infection. 13) In animal survey, 3.1% of dogs were found infected with Clonorchis, decreasing from 21.6% in 1967. 14) The distribution of the first intermediate host, Parafossarulus manchouricus has greatly diminished in this locality and found only in two localized ponds. No Clonorchis infection was found from the snails examined. 15) The second intermediate freshwater fish host has been further limited by extended water pollution. No susceptible fish host could be examined. 16) In conclusion, the endemicity of Clonorchis infection in Croyang Gun, low endemic area, has significantly decreased during the past 16 years. The major cause of the regressive transition of the infection was the water pollution of the freshwater system of this locality. This has upset the ecosystems of the intermediate host of Clonorchis sinensis in many areas of waterbodies and further discouraged to a significant extent the local inhabitants from raw freshwater fish consumption.

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Translocation of Tolclofos-methyl from Ginseng Cultivated Soil to Ginseng (Panax ginseng C. A. Meyer) and Residue Analysis of Various Pesticides in Ginseng and Soil (토양 중 잔류된 Tolclofos-methyl의 인삼(Panax ginseng C. A. Meyer)에 대한 이행 및 잔류 특성)

  • Kim, Ji Yoon;Kim, Hea Na;Saravanan, Manoharan;Heo, Seong Jin;Jeong, Haet Nim;Kim, Jang Eok;Kim, Kwan Rae;Hur, Jang Hyun
    • The Korean Journal of Pesticide Science
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    • v.18 no.3
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    • pp.130-140
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    • 2014
  • Recently, some of the previous studies reported that tolclofos-methyl is still exist in ginseng cultivated soil, even though it is has been banned for ginseng. Therefore, the current study was aimed to examine the levels of absorption and translocation of tolclofos-methyl from ginseng cultivated soil to ginseng root and leaf stem for the period of 1 year. For this study, ginseng plants were transplanted in pots and treated with $5.0mg\;kg^{-1}$ of tolclofos-methyl (50% WP). At the end of each interval periods (every three months) the samples (soil, roots and leaf stems) were collected and analyzed the absorption and translocation levels of tolclofos-methyl using gas chromatography and mass spectrometry (GC-MS). The limit of quantitation of tolclofos-methyl was found to be $0.02mg\;kg^{-1}$ and 70.0~120.0% recovery was obtained with coefficient of variation of less than 10% regardless of sample types. In this study, a considerable amount of translocation of tolclofos-methyl residues were found in soil (4.28 to $0.06mg\;kg^{-1}$), root (7.09 to $1.54mg\;kg^{-1}$) and leaf stem (0.79 to $0.69mg\;kg^{-1}$). The results show that the tolclofos-methyl was absorbted and translocated from ginseng cultivated soil to ginseng root and ginseng leaf stem and found to be decreased time-coursely. Secondly, we were also analyzed soil, root and leaf stems samples from Hongcheon, Cheorwon, Punggi and Geumsan by GC-MS/MS (172 pesticides), LC-MS/MS (74 pesticides). In this study, 43 different pesticides were detected ($0.01{\sim}7.56mg\;kg^{-1}$) in soil, root and leaf stem. Further, tolclofos-methyl was detected 4 times separately in root sample alone which is less ($0.01{\sim}0.05mg\;kg^{-1}$) than their maximum residual limit (MRL) in ginseng. Consequently, the results from both studies indicate the residues of tolclofos-methyl found in ginseng cultivated soil and ginseng ensuring their safety level. Moreover, long-term evaluations are needed in order to protect the soil as well as ginseng free from tolclofos-methyl residues.

A Study on Labor Saving in Paddy Rice Cultivation (논벼재배에 있어서의 노동력 절감에 관한 연구)

  • Young-Chul Chang
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.11
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    • pp.81-97
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    • 1972
  • Experiments and investigations were done basically and practically for the purpose of labor saving in paddy rice cultivation especially on Homizil i.e. hoeing and herbicide, 1969. 8 concrete tanks were established on the open base of Keon Kuk University for comparison of percolation, dissolved oxygen and yield test of rice in the paddy plot of tank. The dimension of the bottom of each tank is square meter. Each of the 4 of the 8 tanks is 21cm in height and each of the remaining 4 tanks is 36cm. Each tank has a system that comprises 2 sets of tubes, each of which has 20 holes of 5mm in diameter scattered every side and is covered with nylon cloth taking water in the tank. One set consists of 4 P.V.C tubes. The first set is situated 8cm below the top of the tank and the second set is located at bottom layer inside the tank. The 4 tubes of each set are combined together and led to the glass tube which protects from inside to outside. And this inside-outside glass tube is connected to the small rubber tube. Also a glass tube is set 4cm below the top of the tank. Paddy loam was filled on sand in each of the tanks in the soil depth of either 15cm or 30cm. The depth of sand was 5cm in the soil depth of 15cm and 10cm in the soil depth of 30cm. (Fig. 1, 2 and 3). The paddy rice was grown in the tank. The percolation of water, the dissolved oxygen and the yield of rice were observed in the tank. And the dissolved oxygen was detected by Winkler method. A sandy paddy field of heavy percolation was selected at the field of the National Agricultural Material Inspection Center in Seoul. It was divided into 9 plots. These plots were given 3 treatments: (A) not hoeing, (B) hoeing one time and (C) hoeing two times. These treatments were replicated 3 times along the latin square design. The paddy rice was grown and sprayed with Stam F-34 in the all plots for the purpose of killing weeds before hoeing. The two types of paddy of field i.e. one for normal percolation and the other for ill drainage were selected at Iri Crop Experiment Station, Jeonla-Bukdo. Each field was divided into 24 plots for 8 treatments. They are: (A) not hoeing; (B) hoeing one time; (C) hoeing two times; (D) not hoeing but treating with herbicide, Pamcon; (E) hoeing one time and weeding two times also treating with herbicide, Pamcon; (F) hoeing two times and weeding one time a], o treating with herbicide, Pamcon; (G) hoeing two times and weeding two times also treating with herbicide, Pamcon, ; (H) usual manner. The labor hours and expenses needed for weeding in the paddy by hoeing were investigated in a farmer at Suwon and the price of herbicide and the yield of rice were taken out at Iri, Jeonla-Bukdo. The results obtained from the above experiments and investigations are as follows: 1. The relationship between percolation and dissolved oxygen shows that a very small amount of oxygen is detected in the soil water under 2cm below surface of earth in the paddy even when percolation is over 4.0cm per 24 hours (Tab. 1). 2. The relationship between percolation and yield of rice shows that the yield of rice increases in the percolation of 0cm and 1.5cm per 24 hours and decreases in the percolation of 2.5cm and 3.4cm in the plot of the 15cm ploughing depth and increases in the percolation of 1.4cm and 3.0cm and decreases in the percolation of 0cm and 4.0cm in the plot of 30cm ploughing depth (Tab. 1 and Fig. 5). 3. The yield of paddy weeded with Stam F-34 in the sandy field of heavy percolation in Seoul was 3.02 tons in the plot of not hoeing, 2.99 tons in hoeing one time and 3.05 tons in hoeing two times per hectare (Tab. 5). 4.1). 4. 1) The yield of rice per 10 ares in the field of normal percolation at Iri was 338kg in not hoeing, 379kg in hoeing one time, 383kg in hoeing two times, 413kg in spraying herbicide, Pamcon, and not hoeing, 433kg in spraying herbicide, Pamcon, and hoeing one time and weeding two times, 399kg in spraying herbicide, Pamcon, and hoeing two times and weeding one time, 420kg in spraying herbicide, Pamcon, and hoeing two times and weeding two times and 418kg in usual manner (Tab. 6-1). 2) The yield of rice per 10 ares in the field of ill drainage at Iri was 323kg in not hoeing, 363kg in hoeing one time, 342kg in hoeing two times, 388kg in spraying herbicide, Pamcon, and not hoeing, 425kg in spraying herbicide, Pamcon, and hoeing one time and weeding two times, 427kg in spraying herbicide, Pamcon, and hoeing two times and weeding one time, 449kg in spraying herbicide, Pamcon, and hoeing two times and weeding two times and 412kg in usual manner (Tab. 6-2). 5. 1) The labor hours for weeding by hoeing was 37.1 hours but 53.5 hours if hours for meal, smoking and so on are included, and the expenses including labor cost needed for weeding by hoeing in the paddy rice was 2, 346 Won per 10 ares at Suwon (Tab. 7). 2) The labor hours for weeding by spraying herbicide with hand sprayer in the paddy rice was about 5 hours per 10 ares at Suwon and the expenses for weeding by spraying herbicide in the paddy rice was 750 Won but 1130 Won if the loss by decrement of rice in the paddy field of ill drainage per 10 ares is calculated in estimation at Iri (Tab. 8). From these observations and investigations it is known that using of some kinds of herbicides Saves labor and expenses of weeding, almost without giving damages to the rice itself, in the field of normal or heavy percolation comparing usual manner of hoeing.

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Job importance, job performance, and job satisfaction in dietitians at geriatric hospitals or elderly healthcare facilities in Jeju (제주지역 요양 (병)원 영양사의 직무중요도, 직무수행도 및 직무만족도 분석)

  • Kang, Hye-Sook;Lee, Yunkyoung;Chae, In-Sook
    • Journal of Nutrition and Health
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    • v.49 no.3
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    • pp.189-200
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    • 2016
  • Purpose: This study analyzed job importance, job performance, and job satisfaction in 38 dietitians working at geriatric hospitals and elderly healthcare facilities in Jeju surveyed from September 15-24, 2014 with the aim of providing basic data for improving the quality of meals and nutrition management for elderly patients. Methods: Data were analyzed using descriptive analysis, ${\chi}^2$-test, t-test, ANOVA, and Pearson's correlation coefficients using the SPSS Win program (version 12.0). Results: Regarding job importance, the average score was 4.29 (out of 5), indicating that hygiene and safety management scored the highest at 4.77 (out of 5), and nutrition management scored the lowest at3.86. In terms of job performance of subjects, the average score was 2.87 (out of 5), indicating that cooking operation management scored the highest at 4.42 (out of 5). Regarding the Importance-Performance Analysis (IPA) of job importance and job performance, hygiene and safety management and cooking operation management scored high for importance and performance (B quadrant) menu management, human resource management, and nutrition management scored low for importance and performance (C quadrant) and purchasing management and financial management were included inD quadrant and A quadrant, respectively. For the level of job satisfaction of subjects, the average score was 3.37 (out of 5), indicating that relationships with colleagues scored the highest at 3.72, and improving professionalism scored the lowest at 2.95. Additionally, job importance and performance of subjects were positively correlated withjob satisfaction (r = 0.395, r = 0.386, both p < 0.05). Conclusion: In conclusion, scores for job importance and job performance of nutrition management were low, and job satisfaction of improving professionalism scored low. Therefore, continuous training and education programs of nutrition management should be provided to improve professionalism of dietitians at geriatric hospitals and elderly healthcare facilities.

Effects of Feeding Eucommia ulmoides Leaves Substituted for Rice Straw on Growth Performance, Carcass Characteristics and Fatty Acid Composition of Muscle Tissues of Hanwoo Steers (볏짚을 두충잎으로 대체급여 시 거세한우의 생산성, 도체특성 및 육의 지방산 조성에 미치는 영향)

  • Kim, J.H.;Kim, Y.M.;Lee, M.D.;Shin, J.H.;Ko, Y.D.
    • Journal of Animal Science and Technology
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    • v.47 no.6
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    • pp.963-974
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    • 2005
  • This study was conducted to examine the growth performance, carcass characteristics, physico-chemical properties and fatty acid composition of muscle tissues of Hanwoo steers when they were fed diets containing four levels of E. ulmoides leaves. Steers were allotted to one of four dietary treatments, which were designed to progressively substitute Eucommia ulmoides for 0, 3, 5 and 10% of the rice straw in the basal diet. Seventy two Hanwoo steers (321±13kg) were used. Average daily gain (0.81-0.86kg) and feed conversion (10.05-10.59) were not changed by feeding E. ulmoides leaves. Emission of fecal ammonia gas was decreased by increasing substitution levels of E. ulmoides leaves. Emission of ammonia gas in feces of steers were significantly (p<0.05) decreased in the 5% and 10% treatments at 40℃ compared with in control (30.6ppm) and 3% treatment (29.8ppm), respectively 20.3 and 21.6ppm. Back fat thickness was higher (p<0.05) in steers fed control diet (15.0mm) than 5 and 10% E. ulmoides diets (10.2 and 10.5mm respectively). The grade ‘A’ appearances of meat yield of steers were increased up to 20% by the 3% substitution of E. ulmoides leaves, and the grades ‘1+’ and ‘1’ appearances of meat quality were significantly improved (p<0.05) by the 5 and 10% Eucommia ulmoides feeding. There was no statistical difference in meat color of loin and top round among all treatments. It appeared that the 5% and 10% E. ulmoides leaves feeding affected (p<0.05) a increase in oleic acid concentration in loin and top round muscles. The concentration of serum cholesterol was lower (p<0.05) in steers fed 10% E. ulmoides (53.3mg/100g) than that of the other treatments (55.7-57.0mg/100g). The diarrhea incidence was about 20.26% in control, while it was lower (p<0.05) in the 5 and 10% E. ulmoides leaves treatments (10.4-12.5%) than control. There was no statistical difference in the occurrences of respiratory disease among all treatments. It is concluded that E. ulmoides leaves should be a prospective feed additive because it contains various functional substances. It is likely that air-dried E. ulmoides leaves can reduce the back fat thickness of Hanwoo steers and the occurrences of diarrhea. Therefore, the 5 and 10% substitution of E. ulmoides for roughage are highly recommended to be used in practice.

Identification of Streptomyces scopuliridis KR-001 and Its Herbicidal Characteristics (Streptomyces scopuliridis KR-001의 분리 동정 및 잡초 방제효과)

  • Lee, Boyoung;Kim, Jae Deok;Kim, Young Sook;Ko, Young Kwan;Yon, Gyu Hwan;Kim, Chang-Jin;Koo, Suk Jin;Choi, Jung Sup
    • Weed & Turfgrass Science
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    • v.2 no.1
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    • pp.38-46
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    • 2013
  • With increasing environmental issues from synthetic chemical herbicides, microbe-originated herbicides could be a fascinating alternative in current agriculture. We isolated Streptomyces strains that produced herbicidal active metabolite(s) against a grass weed Digitaria sanguinalis. According to the result from 16S rDNA sequence comparison with the close strains, the best isolate (Code name MS-80673) was identified as Streptomyces scopuliridis KR-001. The closest type strain was Streptomyces scopuliridis RB72 which was previously reported as a bacteriocin producer. The optimal culture condition of S. scopuliridis KR-001 was $28^{\circ}C$, pH 7.0 and culture period 4 to7 days. Both of soil and foliar application of the crude culture broth concentrate was effective on several troublesome or noxious weed species such as a Sciyos angulatus in a greenhouse and field condition. Phytotoxic symptoms of the culture broth concentrate of S. scopuliridis KR-001 by foliar application were wilting and burndown of leaves, and stems followed by discoloration and finally plant death. In crops such as rice, wheat, barley, hot pepper and tomato, growth inhibition was observed. These results suggest that the new S. scopuliridis KR-001 strain producing herbicidal metabolites may be a new bio-herbicide candidate and/or may provide a new lead molecule for a more efficient herbicide.

Enhanced antimicrobial effectiveness of Omija (Schizamdra chinesis Baillon) by ClO2 (chlorine dioxide) treatment (오미자 수확 후 이산화염소수를 이용한 표면 세척에 따른 미생물 저감 효과)

  • Lee, Seul;Moon, Hey-Kyung;Lee, Su-Won;Moon, Jae-Nam;Lee, Sun-Ho;Kim, Jong-Kuk
    • Food Science and Preservation
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    • v.20 no.6
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    • pp.871-876
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    • 2013
  • The purpose of this study was to investigate antimicrobial effectiveness of Omija (Schizandra chinensis Baillon) treated with $ClO_2$ (chlorine dioxide) concentration (10, 15, 20, 25 and 30 ppm), washing time (30, 60 and 90 sec) and multiple proportion (x1, x2, x3 and x4). The seven groups were divided into control (Omija without washing water treatment), W-T (Omija treated by tap water ($20{\pm}1^{\circ}C$) for 30 seconds), $ClO_2$-10 (Omija treated by 10 ppm $ClO_2$), $ClO_2$-15 (Omija treated by 15 ppm $ClO_2$), $ClO_2$-20 (Omija treated by 20 ppm $ClO_2$), $ClO_2$-25 (Omija treated by 25 ppm $ClO_2$), $ClO_2$-30 (Omija treated by 30 ppm $ClO_2$), and then they were detected number of total aerobic bacteria, yeast and mold. The rate of inactivation was found, for microorganisms of total aerobic bacteria, yeast and mold, to increase with a increase of $ClO_2$ treatment concentration and multiple proportion. No total aerobic bacteria, yeast and mold in $ClO_2$-30 sample treated for 30 sec, $ClO_2$-15 treated for 60 sec and $ClO_2$-10 treated for 90 sec were detected, and in $ClO_2$-30 Omija with multiple proportion ${\times}1$ (Omija : 30 ppm $ClO_2$ solution ratio was 1:1 (w/w)), $ClO_2$-20 with ${\times}2$ (Omija : 20 ppm $ClO_2$ solution ratio was 1:2 (w/w)) and $ClO_2$-15 with ${\times}4$ (Omija : 15 ppm $ClO_2$ solution ratio was 1:4 (w/w)) respectively.

Biological activity and analysis of α-glucosidase inhibitor from mulberry (Morus alba L.) wine (오디와인의 생리활성 및 α-glucosidase 저해제의 분석)

  • Son, Woo-Rim;Choi, Sang-Won
    • Food Science and Preservation
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    • v.20 no.6
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    • pp.877-885
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    • 2013
  • Wine extracts of four different berry fruits, such as mulberry, blueberry, strawberry, and raspberry, were investigated for antioxidant, anti-tyrosinase, and ${\alpha}$-glucosidase activities by using in vitro assays. Additionally, quantitative changes of ${\alpha}$-glucosidase inhibitor in mulberry wine were determined by HPLC according to mulberry cultivars and fermentation process. Among four berry wines examined, mulberry wine showed the most potent ${\alpha}$-glucosidase inhibitory activity with 69.37% at 0.23 mg/mL, while blueberry and strawberry wines exhibited the strongest inhibition against DPPH radical and tyrosinase activity, respectively. Four compounds were isolated and purified from mulberry wine by a series of isolation procedures, such as solvent fractionation, and Diaion HP-20, ODS-A, and Sephadex LH-20 column chromatographies. Among them, Comp. 4 exerted the strongest ${\alpha}$-glucosidase inhibitory activity ($I_C_{50}=31.57{\mu}M$), and its chemical structure was identified as quercetin by UV and NMR spectral analysis. Finally, the "Daeseongppong" (16.83 ppm) muberry wine had larger amount of quercetin than the "Iksuppong" (14.85 ppm) and "Cheongilppong" (8.92 ppm) mulberry wines, but their contents of three mulberry wines decreased considerably with aging process. These results suggest that mulberry wine containing quercetin acted as ${\alpha}$-glucosidase inhibitor may be useful as a potential functional wine for improving diabetic disorder.

Finite Element Method Modeling for Individual Malocclusions: Development and Application of the Basic Algorithm (유한요소법을 이용한 환자별 교정시스템 구축의 기초 알고리즘 개발과 적용)

  • Shin, Jung-Woog;Nahm, Dong-Seok;Kim, Tae-Woo;Lee, Sung Jae
    • The korean journal of orthodontics
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    • v.27 no.5 s.64
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    • pp.815-824
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    • 1997
  • The purpose of this study is to develop the basic algorithm for the finite element method modeling of individual malocclusions. Usually, a great deal of time is spent in preprocessing. To reduce the time required, we developed a standardized procedure for measuring the position of each tooth and a program to automatically preprocess. The following procedures were carried to complete this study. 1. Twenty-eight teeth morphologies were constructed three-dimensionally for the finite element analysis and saved as separate files. 2. Standard brackets were attached so that the FA points coincide with the center of the brackets. 3. The study model of a patient was made. 4. Using the study model, the crown inclination, angulation, and the vertical distance from the tip of a tooth was measured by using specially designed tools. 5. The arch form was determined from a picture of the model with an image processing technique. 6. The measured data were input as a rotational matrix. 7. The program provides an output file containing the necessary information about the three-dimensional position of teeth, which is applicable to several finite element programs commonly used. The program for a basic algorithm was made with Turbo-C and the subsequent outfile was applied to ANSYS. This standardized model measuring procedure and the program reduce the time required, especially for preprocessing and can be applied to other malocclusions easily.

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Radiation, Energy, and Entropy Exchange in an Irrigated-Maize Agroecosystem in Nebraska, USA (미국 네브라스카의 관개된 옥수수 농업생태계의 복사, 에너지 및 엔트로피의 교환)

  • Yang, Hyunyoung;Indriwati, Yohana Maria;Suyker, Andrew E.;Lee, Jihye;Lee, Kyung-do;Kim, Joon
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.22 no.1
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    • pp.26-46
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    • 2020
  • An irrigated-maize agroecosystem is viewed as an open thermodynamic system upon which solar radiation impresses a large gradient that moves the system away from equilibrium. Following the imperative of the second law of thermodynamics, such agroecosystem resists and reduces the externally applied gradient by using all means of this nature-human coupled system acting together as a nonequilibrium dissipative process. The ultimate purpose of our study is to test this hypothesis by examining the energetics of agroecosystem growth and development. As a first step toward this test, we employed the eddy covariance flux data from 2003 to 2014 at the AmeriFlux NE1 irrigated-maize site at Mead, Nebraska, USA, and analyzed the energetics of this agroecosystem by scrutinizing its radiation, energy and entropy exchange. Our results showed: (1) more energy capture during growing season than non-growing season, and increasing energy capture through growing season until senescence; (2) more energy flow activity within and through the system, providing greater potential for degradation; (3) higher efficiency in terms of carbon uptake and water use through growing season until senescence; and (4) the resulting energy degradation occurred at the expense of increasing net entropy accumulation within the system as well as net entropy transfer out to the surrounding environment. Under the drought conditions in 2012, the increased entropy production within the system was accompanied by the enhanced entropy transfer out of the system, resulting in insignificant net entropy change. Drought mitigation with more frequent irrigation shifted the main route of entropy transfer from sensible to latent heat fluxes, yielding the production and carbon uptake exceeding the 12-year mean values at the cost of less efficient use of water and light.