• Journal of Food Hygiene and Safety
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• v.21 no.2
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• pp.82-91
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• 2006

Standard and lead limit test in general test method of Korea, Japan, Joint FAO/WHO Expert Committee of Food Additives (JECFA), USA, and EU on synthetic and natural food additives were compared. There were found that the general test methods in 'Korea Food Additives Code' were different from standards of various institutes on lead limit test. For the lead limit test of food additives, Korea used dithizone method, Japan used atomic absorption spectrophotometry, and USA used dithizone method, flame atomic absorption spectrophotometric method, atomic absorption spectrophotometric graphite furnace method, and APDC extraction method. In addition, JECFA and EU used dithizone method and atomic absorption spectrophotometric method. The dithizone methods of Korea, USA, and JECFA were nearly identical. In the case of USA, JECFA, and EU, the analytical methods for lead limit test were shown in individual monograph. Lead limit test against 13 synthetic, such as magnesium stearate and L-cystine, and 12 natural, such as gua gum and diatomaceous earth, food additives distributed in Korea were performed by the analytical method of each institute. Although all institutes use various methods for analysis of lead, contents of lead in food additives tested fell into the standard of each institute.

• Journal of Embryo Transfer
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• v.16 no.3
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• pp.183-191
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• 2001

This study was designed to establish the superior method for IVF embryos from DNA marker-proved Hanwoo cattle. DNA markers related to marbling score were identified using DNA fingerprinting with Ml3 probe and restriction enzyme Hae III. Oocytes were aspirated from unstimulated. immature ovarian follicles using a combined method of rectal ovarian-palpation and transvaginal ultrasound-guidance(6.5MHz) under local abesthesia. The aspirated oocytes were washed twice with fresh D-PBS containing 5% FBS and were rewashed 4 to 5 times with TCM-199 containing 5% FBS. A morphological grade of I to IV was assigned to each oocyte. Data were analysed using the GLM procedure of SAS. Mean number of follicles identified on ultrasound was 5.5 $\pm$2.9 in right and 4.3 $\pm$2.8 in left ovaries, respectively. The highest follicles(16.6$\pm$2.6) were found in 5101 cow compared to others. Recovery rate of follicular oocytes in individual cow was highest in 5101 cow with 89.3% in > 2mm and 94.0% in $\leq$ 2mm follicles. Total recovery rate was significantly(P<0.01) higher in $\leq$ 2mm(85.7%, 130/154) than > 2mm follicles(74.2%, 201/271). Significantly more oocytcs of Grade IV were recovered from > 2mm follicles. Mean number follicles recovered was 4.8$\pm$3.7. 3.0$\pm$3.4 and 0.3$\pm$0.6 in $\leq$2mm, 2~6mm and $\geq$6mm follicles. respectively. Our results imply that the more fertilizablc oocytes can be recovered from invisible-immature follicles by the combination of simultaneous rectal ovarian-palpation and ultrasound-guided approach in Hanwoo cattle.

• Clinical and Experimental Pediatrics
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• v.46 no.7
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• pp.647-654
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• 2003

Purpose : This study was done to evaluate the parents' or guardians' compliance of obtaining individual informed consent before vaccination and the possible problems of using informed consent. Methods : One hundred and twelve children were randomly selected among 2,820 children who visited Samsung Cheil Hospital during July 2002. A questionnaire about using informed consent of vaccination was given to all parents or guardians of these children. Results : Most of the responders were mothers(80.4%). As for the places of vaccination, 87(77.7%) persons vaccinated their children at general hospitals. In response to a request for informed consent of vaccination, 73(65.2%) complied well with requests every time. In subscribing to informed consent, 62(55.4%) were pleased, 40(35.7%) stated it was necessary despite in inconveniance. Because of dislike of subscribing to informed consent(55), 33(60%) persons stated that it was difficult to subscribe to informed consent during the inconveniant time of nursing baby. Eighty(71.4%) found it useful to read informed consent for an understanding of potential negative reactions. Being informed of potential negative reactions, 105(93.8%) stated that they would vaccinate their children despite of the potential of a worrisome negative reaction. In dealing with negative reaction, 77(68.8%) said that they would contact a hospital, 32(28.6%) said that they would care for their children at home. Eleven(9.8 %) experienced negative reactions after vaccination. Conclusion : Compliance of parents to informed consent was relatively good. Parents or guardians should receive relevant information and the aim of informed consent also should be adequately understood.

• Journal of Korean Society of Forest Science
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• v.70 no.1
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• pp.91-102
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• 1985

Growth and biomass production of natural stands of Quercus variabilis in relation to tree density were studied to obtain basic guide lines for future tending operation. Two natural stands of Quercus variabilis located at 900m (A stand: 6,600trees/ha, $15.84m^2/ha$, $\frac{19}{17-20}$) and 800m (B stand: 4,300trees/ha, $16.65m^2/ha$, $\frac{20}{17-21}$) elevation in Sancheong, Kyongnam Province were selected for the comparative study and following results were obtained through a sample plot method. After diameter of individual trees in the sample plots was measured, twelve average trees from each diameter class were cut felled to measure dry weight of $W_S$, $W_B$, $W_L$, $W_{Ba}$, and standing biomass and biomass production rates by a allometrior regressions related to $D^2H$. Vertical distribution of leaves along the stems indicated that photosynthesis was carried out 2.2m above the ground in Stand A and 1.2m in Stand B. Maximum photosynthesis was located 4.2m and 6.2m above the ground in Stand A and B, respectively. Leaf area index was 4.25ha/ha for Stand A, and 3.89ha/ha for Stand B. Above-ground standing biomass was 49.51 ton/ha for Stand A and 59.20 ton/ha and net annual production was 6.75 ton/ha/yr. for Stand A and 8.99 ton/ha/yr. for Stand B. The ratio of net annual production to standing biomass was 17.5% for Stand A and 16.7% for Stand B. Net assimilation rate was 2.75kg/kg/yr. for Stand A and 3.58kg/kg/yr. for Stand B. Stem wood production rate was 1.46kg/kg/yr. for Stand A and 2.09kg/kg/yr. for Stand B. Bark production rate was 0.60 kg/kg/yr. for Stand A and 0.34kg/kg/yr. for Stand B. Above data indicated that Stand B utilized growing spaces and sites more efficiently than Stand A. It is concluded chat productivity of natural stands of Quercus variabilis can be enhanced through optimization of basal areas and number of tree per hectare and that sound management of natural oak stands should be based on systematic sampling of the area for periodic productivity estimation.

• Clinical and Experimental Pediatrics
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• v.48 no.12
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• pp.1330-1336
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• 2005

Purpose : It has been suggested that changes in cerebral blood flow by ventilator care could be a risk factor in periventricular leukomalacia(PVL) and severe periventricular-intraventricular hemorrhage(PV-IVH). The study aims to assess the relationship between perinatal clinical events, including ventilator care, and the development of PVL and severe PV-IVH; especially, whether ventilator care could be causers of PVL and severe PV-IVH as an individual risk factor. Methods : Among 255 very low birth weight infants who survived in the Fatima neonatal intensive care unit from January 1999 to December 2003, 15 infants with PVL and eight infants with severe PV-IVH were classified as a study group, while 231 infants were enrolled as a control group. The analysis was performed retrospectively with medical records. Results : Twenty four infants were diagnosed with PVL or severe PV-IVH. Asphyxia, recurrent apnea, sepsis, acidosis and ventilator care were significantly increased in the PVL goup. Asphyxia, recurrent apnea, RDS, acidosis and ventilator care were significantly increased in the severe PV-IVH group. Conclusion : Infants with PVL or severe PV-IVH may have multiple perinatal risk factors including asphyxia, recurrent apnea, sepsis, acidosis, RDS and ventilator care. Because most patients with ventilator care have multiple perinatal risk factors, ventilator care does not cause PVL and severe PV-IVH independently. Therefore, incidences of PVL and severe PV-IVH can be decreased by not only gentle ventilation, but also more professional antenatal care.

• Journal of Plant Biotechnology
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• v.33 no.4
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• pp.309-313
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• 2006

Discovery of single nucleotide polymorphisms (SNPs), including small insertions and deletions, is one of the hot topics in genetic research. The most common type of sequence variant consists of single base differences or small insertions and deletions at specific nucleotide positions. Significance of SNPs in rice is increasing for genetic research, positional cloning and molecular breeding. $F_2$ 170 lines and $F_3$ 194 lines derived from Sangjuchalbyeo/HR13721-53-3-1-3-3-2-2 Were used for Searching SNP markers related to bacterial blight resistance. Sangjuchalbyeo is susceptible to bacterial blight, but HR13721-53-3-1-3-3-2-2 has Xa1 gene resistant to bacterial blight. Individual lines were inoculated with $K_1$ race of bacterial blight and resistant or susceptible was evaluated after 3 weeks from inoculation. The genotypes of population were analysed by PCR-RFLP for SNP marker developing. The segregation of $F_2\;and\;F_3$ population showed almost 3:1, 1:1 ratio, respectively. Analysis of genotype using SNP marker is capable of confirming resistance for $K_1$ race and genotype through amplifying the gene using 16PFXal primer and digested the PCR product with Eco RV. There were close relation between resistance test for $K_1$ race and SNP marker genotype. Especially, DNA analysis using SNP marker is capable of judging homozygote/heterozygote in $F_2$ population compared with resistant test for Kl race. So, it seems to improve the selection efficiency in disease resistant breeding.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.2
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• pp.149-158
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• 2018

Agriculture is strongly influenced by climate change such as increased temperature and carbon dioxide ($CO_2$). This study describes the effects of climate change elevated $CO_2$, temperature, and relative drought on growth responses and yield in potato (Solanum tuberosum L.). The assessment was conducted for spring seasons in Soil-Plant-Atmosphere Research (SPAR) chamber at National Institute of Crop Science (NICS). Potatoes exhibit a positive response to $CO_2$ enrichment but water stress primarily reduces potato canopy and tuber yield. Elevated $CO_2$ and temperature increased both dry weight and tuber yield. Elevated $CO_2$ and temperature influenced SPAR 2 plants to a larger, and tuber increased yield up to 28% of than in SPAR 1(30-year average temperature at 450 ppm of $CO_2$). Our study findings indicate that tuber yield increase in potato under high $CO_2$ concentration was due to an increase in the size of individual tubers rather than in the number of the tubers per plant. On other hand, SPAR 3(30-year average temperature $+2.8^{\circ}C$ at 700 ppm of $CO_2$ under water stress) was lower than SPAR 2(30-year average temperature $+2.8^{\circ}C$ at 700 ppm of $CO_2$) nearly 56% of tuber yield due to drought. The results confirm potato drought sensitivity in terms of yield response. The experiment also showed that, in the conditions of climate change, climate change scenarios that improve cropping systems with potato.

• Journal of Preventive Medicine and Public Health
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• v.38 no.1
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• pp.25-37
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• 2005

Objective : To estimate the magnitude of psychosocial distress and examine eligible factors associated with the development of psychosocial distress in Korean employees, using a nationwide sample. Methods : A total of 6,977 workers were recruited from 245 companies. A structured questionnaire was used to assess sociodemographics, health-related behaviors, job characteristics, social support at work, personality traits (locus of control, type A behavior pattern), self-esteem, and psychosocial distress. Results : The results showed that 23 % of workers were categorized as high stress, 73% as moderate, and 5% as normal. Hierarchical multiple regression analysis showed that psychosocial distress was more common in younger workers, both male and female. Regular exercise was negatively associated with increase of psychosocial distress. In job characteristics, as expected, low decision latitude, high job insecurity, and low social support at work were related to high psychosocial distress. Personality traits such as locus of control and type A behavior pattern, and self-esteem were more powerful predictors of psychosocial distress than general characteristics, health-related behavior, and job characteristics. There were some gender differences. While men who are less educated and single (unmarried, divorced, and separated) experienced higher levels of psychosocial distress than those who are educated and married, women who feel high job demand experienced higher levels of psychosocial distress than those who feel low job demand. Conclusions : The proportion of the high stress group was higher than expected, and psychosocial factors like social support and personality characteristics (e. g. locus of control, type A behavior pattern and self-esteem) were more significant factors for psychosocial distress than other variables. This finding suggests that some psychosocial factors, especially inadequate social support, low self-esteem and lack of internal locus of control for the development of psychosocial distress, will also operate as an intervention strategy in the worksite stress reduction program. It is strongly required that worksite stress reduction programs should be established in at both occupational and level as well as in individual levels.

• The Korean Journal of Nuclear Medicine
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• v.28 no.1
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• pp.124-132
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• 1994

Radioactive iodine has been widely used in patients with thyroid cancer combined with surgical treatment. However, due to individual variations in absorption and excretion and uptake by tumor tissue of radioactive iodine, there are differences in therapeutic effect and adverse effects even if the same doses are administrated. So this study compared the therapeutic effect and radiation hazard by measuring internal radiation dose. Of total 27 patients with well differentiated thyroid cancer who had been thyroidectomized, we administered radioactive iodine 100 mCi, 150 mCi, 200 mCi. According to BEL DOSIMETRY PROTO-COL, beta and gamma ray dose were estimated from a pelt of the logarithm of the percent of dose per liter of whole blood versus day, and percent dose retained versus day using somilogarithmic paper, respectively. 1) Physical dose to whole blood averaged $56.54{\pm}13.02$ rad in 100 mCi administered group, $76.83{\pm}19.97$ rad in 150 mCi administered group, $95.08{\pm}25.51$ rad in 200 mCi administered group and there has been a significant correlation among the groups. 2) Mean percent dose retained 48 hours later was 26.34%. 3) There was no significant correlation of physical dose between absence and presence of metastasis. 4) 17 of 19 patients who has been followed up with TSH and serum throglobulin, Thallium scan were successfully ablated by radioactive iodine. 5) Leukocyte, lymphocyte, neutrophil, platelet counts all deelined in 4.6 weeks and most of all were restored 3 months later. 6) There was no significant correlation between physical dosimetry and biologic dosimetry. Generally administered doses of radioactive iodine (100-200 mCi) to patients with thyroid cancer postoperatively had developed transient bone marrow suppression and minimal chromosomal aberration, but they were within safety dose to blood (200 rad). And there has been no significant differences in residual dose 48 hours later between Korean and western people.

• Economic and Environmental Geology
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• v.49 no.4
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• pp.301-314
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• 2016

Disused Sealed Radioactive Sources (DSRSs) are stored temporally in the centralized storage facility of Korea Radioactive Waste Agency (KORAD) and planned to be disposed in the low- and intermediate-level radioactive waste (LILW) disposal facility in Gyeongju city. In this study, preliminary post-closure safety assessment was performed for DSRSs in order to draw up an optimum disposal plan. Two types of disposal options were considered, i.e. engineered vault type disposal and rock cavern type disposal which were planned to be constructed and operated respectively in LILW disposal facility in Gyeongju city. Assessment end-point was individual effective dose of critical group and calculated by using GoldSim code. In normal scenario, the maximum dose was estimated to be approximately $1{\times}10^{-7}mSv/yr$ for both disposal options. It meant that both options had sufficient safety margin when compared with regulatory limit (0.1 mSv/yr). Otherwise, in well scenario, the maximum dose exceeded regulatory limit of 1 mSv/yr in engineered vault type disposal and the exposure dose was mainly contributed by $^{226}Ra$, $^{210}Pb$ (daughter nuclide of $^{226}Ra$) and $^{237}Np$ (daughter nuclide of $^{241}Am$). For rock cavern type disposal, even though the peak dose satisfied regulatory limit, the exposure doses by $^{14}C$ and $^{237}Np$ were relatively high above 10% of regulatory limit. Therefore, it is necessary to exclude $^{14}C$, $^{226}Ra$ and $^{241}Am$ for two type of disposal options and additional management such as long-term storage and development of disposal container for those radionuclides should be performed before permanent disposal for conservative safety and security.