• Korean Journal of Organic Agriculture
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• v.10 no.2
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• pp.111-120
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• 2002

This study was conducted to investigate the effect of foliar application of Chitosan and seedling types on increasing the production of fall-growing potatoes(Solanum tuberosum) at the height of 250m from the sea in Jeju Island. The experiment main-plots consisted of four Chitosan applications, and subplots had three seedling types as cutting plug seedlings, mine-tuber plug seedling planting plot and seed potatoes planting plot. The foliar application of Chitosan of 2000ppm was carried out 0, 1, 3, 5 times at intervals of ten days after ten days of transplanting. Plant height and top dry weight were significantly more vigorous as three to five application of Chitosan. In the small tubers(under 80g), the number of tubers and tuber yield were relatively increased in the seed potatoes planting plot and mine-tuber plug seedling plot, but the large tubers(over 80g) was higher in the cutting plug seedling planting plot. T-N content in leaves was increased as the number of application of Chitosan was increased. A similar tendency was shown in K, P Ca, Mg and Na. The growth and tuber yield in cutting plug seedlings, mine-tuber plug seedling planting plot and seed potatoes planting plot were effectively increased as three to five foliar applications of Chitosan was increased.

• Korea journal of population studies
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• v.19 no.1
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• pp.93-122
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• 1996

This is a study of the determinants of sexual, contraceptive, and abortion behavior among unmarried female adolescents and young adults, which has emerged as a growing and serious health problem in Korea. As part of a larger project, data were gathered in three export zones: Kuro (Seoul), Kumi (Kyngbuk) Masan Changwon (Kyongnam) ; and the study samples are regrouped into three categories: 1) factory workers, i.e. , the reference group serving as program participants, 2) entertainment workers, and 3) ob-gyn patients. This study indicates that entertainment workers are at highest risk of experiencing premarital sex, STDs, contraceptive failure, unwanted pregnancies, and induced abortion. Of them, 20 percent had STDs as a result of first sexual experience: and about seven tenths had two or more pregnancies due to the adoption of low-efficacy methods. The proportion of those who had ever been pregnant was 60 percent for the group as a whole: 36 percent for the program participants: 64 percent for the entertainment workers ; and 91 percent four the ob-gyn patients. These proportions are exactly the same for abortion in each group, which means that all pregnancies ended in induced abortion. Of the respondents who said that they were sexually active at the time of survey, abortions were very high: 1.6 for the program participants, 2.3 for the entertainment workers, and 1.9 for the ob-gyn patients. About 80 percent of the women had abortions during the first trimester, and two thirds of the first abortions took place between the ages of 20 and 23. About one fourth experienced post-abortion complication, which was highest among the program participants (39 percent). Sixty percent of those with complications visited a hospital or took medicine to treat the problem. Even after the experience of induced abortion, the use of contraception was very low, except among the entertainment workers, whose level of use reached 53 percent. The most obvious recommendation, arising from this research, is that 'good-quality' counselling and family planning services be established under the auspices of both national and local government, particularly targeted for the entertainment workers as well as the factory workers in various textile, electronic, manufacturing, and other industrial sectors. We believe that entertainment sectors should be restructured radically so that young women who work for amusement bars and other entertainment sectors obtain protection from the risk of having unwanted pregnancies, STDs, and induced abortion.

• Microbiology and Biotechnology Letters
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• v.41 no.4
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• pp.383-390
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• 2013

Several yeasts were isolated from flowers found in Gyonggi-do Province and Jeju island in Korea. They were then identified by a comparison of their PCR-amplified D1/D2 regions of 26S rDNA, internal transcribed spacer 1 and 2 inclusive of 5.8S rDNA, using the BLAST database. A total of fifty four yeast strains were isolated from wild flowers in Gyonggi-do and the genus Pseudozyma was noted as being dominant. A total of thirty two strains were isolated from Songaksan and Seongsan-ilchulbong in Jeju island and Sporobolomyces ruberrimus was seen to be dominant. The anti-gout xanthine oxidase inhibitory activities of the culture broths and cell-free extracts from eighty six yeast strains were then determined. The cell-free extracts of Pseudozyma hubeiensis 228-S-1 exhibited the highest xanthine oxidase inhibitory activity of 19.6%. The XOD inhibitor was also maximally produced when Pseudozyma hubeiensis 228-S-1 was cultured at $30^{\circ}C$ for 36h in YEPD medium.

• Korean journal of applied entomology
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• v.23 no.2 s.59
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• pp.109-115
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• 1984

This study was conducted to investigate the bionomics, host range and damage aspect of Japanese juniperus bark borer, Semanotus bifasciatus M., which shoves the severe damage for the Juniperace in Chonnam province, recently. Host plants were Juniperus virginiana, J. chinensis var. kaizuka, J. chinensis, Biata orientalis var. nepalensis, Chamaccyparis ostus and Thujopsis dolabrata. Out of those, J. chinensis var. kaizuka is newly investigated in this study. Damage rate in each area was $16.5\%$ in Kwangju, $4.25\%$ in Damyang ana $6.5\%$ in Hwasoon. Adults appear once a year, with a peak at late March to early April. Adults emergence during the day showed the peak at 13 to 15 hours and were influenced in the maximum temperature in a day. Attack direction of larva after invasion in the stem was $62\%$ toward base, $22\%$ toward tip and $16\%$ toward horizon, and the damage in each DBH (Diameter of breast height) was the greatest at $30\~40mm$. At period of each stage, egg was $15.8\~19.7$ days, larva was $l12\~126$ days and pupa was $15\~21$ days. Longevity of adult was 19 days for female and 16 days for male.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.2
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• pp.121-128
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• 2009

A field study was conducted from 2007 to 2008 at Department Rice and Winter Cereal Crop, NICS, RDA, to evaluate the effects of harvest time and cultivar on forage yield and quality. Four whole crop barley cultivars ('Youngyang', 'Wooho', 'Yuyeon' and 'Dami') were selected and harvested on five separate growth stages (heading, and intervals of 1, 2, 3 and 4 weeks after heading) in split plot design with three replications. Results from this experiment indicated significant differences due to harvest time and cultivar in dry matter yield and total digestible nutrients (TDN) yield for forage. The interaction between harvest time and cultivar was not significant. The TDN yield trends were increasing with later harvest time due to higher dry matter yield and TDN content. This experiment provides some interesting results with respects to optimum harvest time, feed value and ultimately yield for the different whole crop barley cultivars.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.1
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• pp.77-84
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• 1998

In order to investigate microbiological control of malodors, particularly including ammonia, the effect of three thermophilic ammonium tolerant bacteria strains. TAT112. TAT117 and TAT119, were tested during composting of pig manure in the laboratory scale composters. The total weight, volatile solids and BOD of the pig manure compost were decreased during composting process in all treatments. The temperature in all treatments rose in first 3 days dramatically, but that in control without inoculation reached its maximum most lately among the treatments. The nitrogen content of drain water accumulated inside and outside composter, and trapped in 6N $H_2SO_4$ was lower in TAT112 inoculated composter than in control. However, it was not lower in the treatment of TAT117 and TAT119 inoculated. Ammonia concentration in the exhaust gas monitored everyday during composting also demonstrated that it was lowest at TAT112 inoculated among all treatments. It was appeared to have an effect on reducing ammonia emission at the treatment of TAT112 inoculated than the control.

• Journal of the Korean Chemical Society
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• v.67 no.4
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• pp.296-305
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• 2023

This study analyzed the information-seeking behavior of preservice science teachers by observing the process of seeking information needed in a Socioscientific issues (SSI) debate class. Twenty-four fourth-year preservice science teachers participated in the study, and the SSI debate was conducted on the topic of biofuels. The results of the study revealed that preservice teachers go through the process of 'Searching', 'Reviewing', 'Interpreting', and 'Evaluating and Reorganizing' stages when seeking information. The searching stage is divided into identifying topics, role division, and standard setting for a search. The reviewing stage is divided into reviewing sources and reviewing contents. The interpreting stage is divided into interpreting an information and interpreting information from an integrating aspect. In addition, the evaluating and reorganizing stage is divided into evaluating information and reorganizing information. It was found that preservice teachers have difficulty reviewing information and interpreting multiple sources of information in an integrated aspect. Also, it was found that evaluating information activity among preservice teachers' information-seeking behavior affects the level of argumentation in discussions.

• Korean Journal of Poultry Science
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• v.19 no.1
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• pp.1-12
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• 1992

This study was divided into experiment I(129g egg-albumen plus 150g sucrose) and experiment II(161g egg-albumen plus 150g sucrose) which were subdivided into groups treated with 0, 8.71, 17.43 and 26.149 egg yolk. These experiments were incubated in a shaking water bath(5$0^{\circ}C$) with a speed of 92(turnaround) per minute for a period of times. The pH and specific gravity were measured after 2, 4, 6, 8, 10 and 12 hour incubations. The results obtained were as follows： 1. The pH and specific gravity were steadily increased by shaking time, but variably was influenced by the amount of egg yolk and egg-albumen. 2. In the groups treated with egg-albumen, egg yolk, and sucrose of experiments I and II, pH was increased by the amount of egg-albumen in conjunction with shaking time, but specific gravity was decreased. 3. Ten hours after shaking maximum pH 8.60 was shown in the groups treated with 161g egg-albumen ： however, in ：he groups treated with 129g egg-albumen the maximum pH 8.39 was shown 12 hours after shaking. The different time exhibited maximum pH resulted from the amount of egg-albumen used. 4. The pH specific gravity were higher in the ,groups treated without egg yolk than in the groups with egg yolk. 5. In the experiment I which was added four levels of egg yolk to 1509 of sucrose and 129g of egg albumen, specific gravity(Table 2) had a high (r＝0.9692$^{* *}$) correlation with pH (Table 1) and the regression equation between specific gravity and pH (X) was Y＝0.050＋0.145x. 6. In the experiment II which was added four levels of egg yolk to 150g of sucrose and 161g of egg albumen, specific gravity(Table 4) had a high (r＝0.8963$^{* *}$) correlation with pH (Table 3) and the regression equation between specific gravity and pH (X) was Y＝0.294＋0.110X.10X.

• Clinical and Experimental Pediatrics
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• v.46 no.6
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• pp.561-565
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• 2003

Purpose : Urinary tract infection(UTI) is the most common bacterial infectious disease that may induce severe renal injury unless early diagnosis and appropriate treatment are performed. If recurrent UTI is prevented, renal injury can be also reduced. Therefore, we studied the risk factors of recurrent UTI in children. Methods : We performed a retrospective study of 168 children(58 girls and 110 boys) who were treated for UTI in the Department of Pediatrics, Korea University Medical Center, during 2000-2001. Among 168 children, 93 children were followed up for more than six months. For the detection of recurrence of UTI, we performed monthly routine urine cultures and physical examinations. Results : The total rate of recurrence was 32.3%. The recurrent rate in boys and girls were 37.1% and 17.4%, respectively(P<0.05). The most common causative bacteria in the first onset and in recurrence were Escherichia coli. There was a significant difference in the onset age of UTI between boys with recurrence($4.8{\pm}1.0months$) and without recurrence($16.5{\pm}3.8months$)(P<0.01). In 77% of cases, urinary tract infection recurred within six months of the first infection. The time of the first recurrence after UTI was $3.7{\pm}0.6months$ in boys and $14{\pm}8.2months$ in girls(P<0.01). The number of recurrences showed a significant difference between the group under the age of one year($0.69{\pm}0.8/year$) and those above the age of one year($0.16{\pm}0.4/year$)(P<0.05). There was no difference in the recurrent rate between those with structural abnormality and those with normal anatomy. Conclusion : Monthly routine urine cultures are efficient in detecting recurrent UTI in children. Because the male sex and young age especially less than one year of age are risk factors for increased recurrence rate of UTI, these children should be followed-up with urine cultures.

• Childhood Kidney Diseases
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• v.11 no.1
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• pp.24-31
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• 2007

Purpose : Nitric oxide(NO) is a very potent vasodilator synthesized from L-arginine by endothelial cells. We investigated whether urinary NO excretion was altered in various renal diseases in children and whether urinary NO excretion could be used in predicting pathologic causes and fibrosis in renal diseases in children. Methods : We recruited 48 patients(32 minimal change nephrotic syndrome[MCNS] and 16 vesicoureteral reflux[VUR] patients from the pediatric renal clinic in Korea University Guro Hospital. We measured the concentration of nitrite$(NO_2)$ and nitrate$(NO_3)$ by Griess reaction and that of creatinine(Cr) by Jaffe method in randomized spot urines. We then analyzed the urinary$(NO_2+NO_3)/Cr$ ratios and compared the values between each patient group. Urinary $(NO_2+NO_3)/Cr$ ratios were also evaluated according to the recurrence and the degree of proteinuria at sampling in the MCNS group and compared according to the presence of renal scarring and the grade of reflux in the VUR group. Results : The ratios of urinary$(NO_2+NO_3)/Cr$ were significantly increased in the VUR and MCNS groups, as compared to the control group. In the MCNS group, a higher level of urine $(NO_2+NO_3)/Cr$ was observed In frequent relapse patients(relapse over four times within one year after first diagnosis) and the patients with severe proteinuria at sampling, respectively. The VUR group with renal scars also showed a higher level of urinary$(NO_2+NO_3)/Cr$ compared to that without scars. Conclusions : In summary, VUR may play a role in the pathogenesis of VUR and MCNS. NO also seems to affect proteinuria and renal scar formation. (J Korean Soc Pediatr Nephrol 2007;11:24-31)