• The Korean Journal of Nuclear Medicine
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• v.27 no.2
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• pp.218-222
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• 1993

Lung/heart uptake ratio (L/H R) in $^{201}Tl$ myocardial perfusion scan is a reliable marker for long-term prognosis in patients with coronary artery disease. However, the value of L/H R in $^{99m}Tc-MIBI$ myocardial perfusion scan is controversial in determining the prognosis and severity of the coronary artery disease. The purpose of this study was to determine the clinical implications of L/H R in $^{99m}Tc-MIBI$ myocardial perfusion scan. Forty five patients who received $^{99m}Tc-MIBI$ myocardial perfusion scan were divided into control group and coronary artery disease (CAD) group by their clinical findings, EKGs, and $^{99m}Tc-MIBI$ myocardial perfusion scans. Twenty five patients in CAD group were divided into ischemic group and infarct group according to their results from $^{99m}Tc-MIBI$ myocardial perfusion scan. L/H R was calculated on the anterior planar view, 60 minutes after infusion of dipyridamole. Two regions of interest (ROI) were placed on the left lung area 8 pixel above the left ventricle and on the myocardial area which had the highest radioactivity. In the control group, there were no significant differences of L/H R according to sex and age. No significant difference of L/H R was found between the control and CAD group ($0.26{\pm}0.06,\;0.29{\pm}0.05$, p>0.05). In the CAD group, there was also no significant difference of L/H R between the ischemic group and infarct group ($0.29{\pm}0.07,\;0.30{\pm}0.04$, p>0.05). L/H R in CAD group did not show correlations with the defect area of stress polar map (r=0.18, p >0.05) and with the sum of severity weighted extent score or reversibility score which represent severity and extent of myocardial perfusion defect area in stress (r=0.18, p>0.05). We conclude that it is difficult to use L/H R as a marker for severity of CAD in dipyridamole $^{99m}Tc-MIBI$ myocardial perfusion scan.

• Journal of Radiation Protection and Research
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• v.42 no.2
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• pp.77-82
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• 2017

Background: This study aims to predict the midline dose based on the entrance and exit doses from optically stimulated luminescence detector (OSLD) measurements for total body irradiation (TBI). Materials and Methods: For TBI treatment, beam data sets were measured for 6 MV and 15 MV beams. To evaluate the tissue lateral effect of various thicknesses, the midline dose and peak dose were measured using a solid water phantom (SWP) and ion chamber. The entrance and exit doses were measured using OSLDs. OSLDs were attached onto the central beam axis at the entrance and exit surfaces of the phantom. The predicted midline dose was evaluated as the sum of the entrance and exit doses by OSLD measurement. The ratio of the entrance dose to the exit dose was evaluated at various thicknesses. Results and Discussion: The ratio of the peak dose to the midline dose was 1.12 for a 30 cm thick SWP at both energies. When the patient thickness is greater than 30 cm, the 15 MV should be used to ensure dose homogeneity. The ratio of the entrance dose to the exit dose was less than 1.0 for thicknesses of less than 30 cm and 40 cm at 6 MV and 15 MV, respectively. Therefore, the predicted midline dose can be underestimated for thinner body. At 15 MV, the ratios were approximately 1.06 for a thickness of 50 cm. In cases where adult patients are treated with the 15 MV photon beam, it is possible for the predicted midline dose to be overestimated for parts of the body with a thickness of 50 cm or greater. Conclusion: The predicted midline dose and OSLD-measured midline dose depend on the phantom thickness. For in-vivo dosimetry of TBI, the measurement dose should be corrected in order to accurately predict the midline dose.

• The Journal of the Korea Contents Association
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• v.22 no.6
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• pp.530-540
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• 2022

The aim of this study was to analyze the impacts of perceived economic instability on drinking frequency in the mist of exercising the strong social distancing in the early phase of COVID19 pandemic. The data were collected from 1,117 adults aged between 19 and 70 across the nation from May 13 to May 19 in 2020 by Embrain, an on-line research company. We used only 820(73.4%) out of 1,117 who answered that they had a drinking in 2020. Bi-variate analysis and multivariate multinomial logistic regression were performed using STATA16. Multinomial logistic regression results showed that the increase of employment instability was related to the increase of drinking frequency, whereas the increase of income instability was related to the decrease of drinking frequency. In sum, the impact of perceived economic instability during the early phase of pandemic may be presented as an increase or decrease of drinking frequency depending on the effect of employment instability and income instability.

• The Journal of the Petrological Society of Korea
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• v.19 no.3
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• pp.167-180
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• 2010

The geochemical studies on the plutonic rocks of the Geochang, the central part of the Ryongnam massif, were carried out in order to constrain the petrogenesis and the paleotectonic environment. The objects of this study are dioritic rocks, biotite granite and hornblende granite. The modal compositions indicate that the dioritic rocks are quartz diorite, quartz monzodiorite, tonalite, biotite granites are granodiorite, granite and hornblende granites are granite, quartz monzonite, quartz syenite. These rocks belong to the calc-alkaline series. Especially, trace elements such as Sr, Nb, Sr, Ti are depleted, suggesting that these rocks are produced in the subduction zone related to calc-alkaline series. Also, the studied granitic rocks correspond to peraluminous and I-type. Chondrite-normalized REE patterns show that LREE are enriched much more than HREE, and have weak Eu(-) anomaly. It is similar to pattern of Jurassic granitoids in the South Korea. Total REE value of the biotite granite and hornblende granite ranges 76.21~137.05 ppm and 73.84~483.21 ppm, respectively, also $(La/Lu)_{CN}$ value ranges 9.61~36.47 and 7.17~21.85. It is suggest that studied rocks suppor their emplacement at active continental margin. Also, these rocks are derived from magma generated by partial melting of lower continental crust materials.

• Tuberculosis and Respiratory Diseases
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• v.50 no.3
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• pp.343-352
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• 2001

Background : Advanced chronic obstructive pulmonary disease is characterized by progressive pulmonary hypertension leading to right heart dysfunction, which plays a Important role in clinical evaluation but remains difficult and challenging to quantify. The noninvasive doppler echocardiographic value referred to as the Tei index has been suggested as a simple, reproducible and reliable parameter of the right ventricular function. The purpose of this was to assess the right ventricular function in patients with chronic obstructive pulmonary disease using the Tei index and to evaluate its relationship with the pulmonary functional status. Methods : The study population comprised of 26 patients with chronic obstructive pulmonary disease and 10 normal control subjects. The Tei index was obtained by dividing the sum of the isovolumetric contraction and the relaxation times by the ejection time using a pulsed-wave doppler. It was compared with the other available Doppler echocardiographic parameters of systolic or diastolic function and with the pulmonary function of the patients. Results : The Tei indices of the patients with COPD were significantly higher than those of normal subjects($0.45{\pm}0.17$ vs. $0.27{\pm}0.03$, p<0.01). The isovolumetric contraction time/ejection time($0.32{\pm}0.08$ vs. $0.25{\pm}0.05$, p<0.05), the isovolumetric relaxation time/ejection time($0.29{\pm}0.16$ vs. $0.15{\pm}0.08$, p<0.05)and the preejection period/ejection time ($0.46{\pm}0.10$ vs. $0.38{\pm}0.06$, p<0.05) were prolonged and the ejection time ($255.2{\pm}32.6$ vs. $314.2{\pm}16.5$ msec, p<0.05) was significantly shortened in patients with COPD compared to normal subjects. The tei indices were inversely correlated with the $FEV_1$ (r=-0.46, p<0.05) and were prolonged significantly in patients with a severe obstructive ventilatory dysfunction(less than 35% of predicted $FEV_1$) compared to those with a mild and moderate ventilatory dysfunction. The tei indices showed an inverse correlation to with the ejection time (r=-0.469), the isovolumetric contraction time/ejection time(r=0.453), the isovolumetric relaxation time/ejection time(r=0.896) and the preejection period/ejection time(r=0.480). Conclusion : The tei index appeared to be a useful noninvasive means of evaluating the right ventricular function. It revealed a significant correlation with the pulmonary function in patients with COPD.

• Journal of Aquaculture
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• v.14 no.3
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• pp.181-195
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• 2001

To stabilize the lantern cage culture system of Patinopecten yessoensis(Jay) in the eastern coast of Korean peninsula, optimum conditions such as time of transplantation, rearing density and depth, and time of harvest were identified. During the period from January 1991 to December 1998, the water temperature ranged from 4.7 to 21.4$^{\circ}C$ at 15-30 m depth and 4.9 to 25.7$^{\circ}C$ at the surface; these thermal ranges were within the optimal ranges (5-23$^{\circ}C$) prevailing at 15-30 m depth at surface water. Annual thermal changes indicated that the prevailing temperature during the years 1993 and 1996 was near optimum, but higher during the years 1994, 1997 and 1998, when mass mortality and growth retardation occurred. Salinity (32.0- 34.4$\textperthousand$) and dissolved oxygen (4.14 -8.11 $\mu\textrm{g}$/l) at 15 m depth were well within the optimum ranges. The chlorophyll concentrations (0.06 - 2.73$\mu\textrm{g}$/l) indicated that the study area was oligotrophic, although mass mortality did occur, when chlorophyll concentrations were high, especially in summer. Hence water temperatures and chlorophyll concentration are major factors related to survival and growth of the scallop. In terms of the shell height maximum growth occurred during spring (March-May; 8 - l3$^{\circ}C$) and fall (October-December; 11-l7$^{\circ}C$) in the lantern cage culture. Slow growth was recorded during late winter January-february; less than 7$^{\circ}C$) and mid-summer (August- September; more than 18$^{\circ}C$). Daily growth of shell height and total weight were 0.02∼0.24 mm and -0.07∼0.90 g at the rearing density of 12 individuals per net. Optimal .earing density in the lantern cage (ø50${\times}$20 cm) was 10∼15 individuals with the shell height of 5∼6 cm. The fastest growth rates were observed at 15∼20 m depth; however, it is recommended that 20∼30 m would be optimal. The scallops require 22 months to attain the commercial size of 10 cm shell height and 140 g total weigh, and are best harvested and sold during March-April.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.2
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• pp.1000-1009
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• 2014

This study selected 582 senior citizens who used 6 senior welfare centers in 7 districts, Daegu and analyzed questionnaires for them from January 9 through June 5, 2013 in order to look into their subjective oral health, social efficacy and quality of life according to their subjective cognition of oral health and their quality of life related to oral health according to sociodemographic characteristics and drew the following conclusions: Sex was statistically significant in toothache and xerostomia; age, in oral health, dysmasesis, toothache, periodontal complications and xerostomia; the level of education, in oral health, dysmasesis, toothache and periodontal complications; and the number of family members living together, in dysmasesis, toothache, periodontal complications, xerostomia and halitosis. Their responses to the question about their social efficacy according to oral health included: 'My oral health is not good' 3.11 points; and 'My jaw crackles or hurts' 1.99 points. In social efficacy according to their cognition of oral health, their health was 2.05 points while in the quality of life, their health was 3.41 points. In the scores of the quality of life related to oral health, for their health, functional limitation was 2.13 points; physical pain, 2.53; psychological discomfort, 2.17; physical limitation, 2.31; degradation of psychological ability, 2.06; degradation of social ability, 1.81; and social disadvantage, 1.99. In sum, it is judged that senior citizens' quality of life as well as their oral health will be enhanced when active seeking for plans to prevent the progress of oral diseases is sufficiently considered through continuously providing oral health education for the promotion of geriatric oral health and developing preventive programs.

• Journal of Life Science
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• v.22 no.3
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• pp.366-372
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• 2012

This study was conducted to estimate the extent of linkage disequilibrium (LD) and effective population size using whole genomic single nucleotide polymorphisms (SNP) genotyped by DNA chip in Hanwoo. Using the blood samples of 35 young bulls born from 2005 to 2008 and their progenies (N=253) in a Hanwoo nucleus population collected from Hanwoo Improvement Center, 51,582 SNPs were genotyped using Bovine SNP50 chips. A total of 40,851 SNPs were used in this study after elimination of SNPs with a missing genotyping rate of over 10 percent and monomorphic SNPs (10,730 SNPs). The total autosomal genome length, measured as the sum of the longest syntenic pairs of SNPs by chromosome, was 2,541.6 Mb (Mega base pairs). The average distances of all adjacent pairs by each BTA ranged from 0.55 to 0.74 cM. Decay of LD showed an exponential trend with physical distance. The means of LD ($r^2$) among syntenic SNP pairs were 0.136 at a range of 0-0.1 Mb in physical distance and 0.06 at a range of 0.1-0.2 Mb. When these results were used for Luo's formula, about 2,000 phenotypic records were found to be required to achieve power > 0.9 to detect 5% QTL in the population of Hanwoo. As a result of estimating effective population size by generation in Hanwoo, the estimated effective population size for the current status was 84 heads and the estimate of effective population size for 50 generations of ancestors was 1,150 heads. The average decreasing rates of effective population size by generation were 9.0% at about five generations and 17.3% at the current generation. The main cause of the rapid decrease in effective population size was considered to be the intensive use of a few prominent sires since the application of artificial insemination technology in Korea. To increase and/or sustain the effective population size, the selection of various proven bulls and mating systems that consider genetic diversity are needed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.14 no.1
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• pp.1-14
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• 1978

To study the fluctuation of cold water in the East China Sea in summer heat budget of the Yellow Sea in winter was analysed based on the oceanographic and meteorological data compiled from 1951 to 1974. The maintain value of insolation was observed in December($160{\sim}190ly/day$), while the maximum in February ($250{\sim}260ly/day$). The range of the annual variation was found to be less than 50 ly/day. The value of the radiation term ($Q_s-Q_r-Q_h$) was remarkably small (mean 20 ly/day) in winter. It was negative value in December and January, and a positive value in February. The minimum total heat exchange from the sea ($Q_({h+c}$) was found value (471 ly/day) in February 1962, and the maximum (882 ly/day) in January 1963. The annual total heat exchange was minimum (588 ly/day) in 1962, and maximum (716 ly/day) in 1968. If the average deviation of mean water temperature at 50m depth layer were assumed to be the horizontal index ($C_h$) of colder water, $C_h$ is $C_h=\frac{{\Sigma}\limit_i\;A_i\;T_i}{{\Sigma}\limit_i\;A_i}$ where $A_i$ denotes the area of isothermal region and $T_i$ the value of deviation from mean sea water temperature. The vertical index ($C_v$) of cold water can be expressed similarly. Consequently the total index (C) of cold water equals to the sum of the two components, i.e. $C=C_h$＋$C_v$. Taking the deviation of mean sea surface temperature(T'w) in the third ten-day of Novembers in the Yellow Sea as the value of the initial condition, the following expressions are deduced : $C－T'w＝32.06 - 0.049$ $\;Q_T$ $C_h-T'w/2=12.20-0.019\;Q_T$ $C_v-T'w/2＝18.07-0.027\;Q_T$ where $Q_T$ denotes the total heat exchange of the sea. The correlation coefficients of these regression equations were found to be greater than 0.9. Heat budget was 588 ly/day in winter, and minimum water temperature of cold water was $18^{\circ}C$ in summer of 1962. The isotherm of $23^{\circ}C$ extended narrowly to southward up to $29^{\circ}N$ in summer. However, heat budget was 716 ly/day, and minimum water temperature of cold water was $12^{\circ}C$ in summer of 1968. The isotherm of $23^{\circ}C$ extended widely to southward up to $28^{\circ}30'N$ in summer. As a result of the present study, it may be concluded that the fluctuation of cold water of the East China Sea in summer can be predicted by the calculation of heat budget of the Yellow Sea in winter.

• Journal of Aquaculture
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• v.9 no.1
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• pp.25-42
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• 1996

The study has been conducted to know an appropriate feeding strategy and effects of the rearing density on larval growth of the rockfish, Sebastes schlegeli. The results obtained are as fellowed ; 1. Thirty-day-old larvae reached at $25.25{\pm}3.76$ mm in total length and $0.23{\pm}0.07$ g in body weight in experiment A, at which rotifer was provided from the beginning to the end of 30-day experiment, Anemia from 3th to 18th day, and artificial feed from 13th to 30th day after hatching. When rotifer was provided for 30 days, Artemia from 6th to 18th day, and artificial feed from 18th to 30th day after hatching (experiment B), these larvae grew up to $27.52{\pm}2.50$ mm in total length and $0.26{\pm}0.06$ g in body weight. On the other hand, when rotifer and artificial feed were supplied with the same time schedule as shown in experiment B, and Artemia was feed from 6th to 30th day after hatching (experiment C), the total length and body weight of those larvae were $23.22{\pm}3.44$ mm and $0.15{\pm}0.05$ g, respectively. The best result for larval growth was obtained from experiment B. The survival rates estimated were $57.6\%$ in experiment A, $66.4\%$ in experiment B, and $44.4\%$ in experiment C. 2. The growth in total length of the larvae according to their rearing days could be represented by the following equations : Experiment A : Y=4.350+0.116X+$1.887X^2$ (r=0.993) Experiment B : Y=4.500+8.931X+$2.221X^2$ (r=0.994) Experiment C : Y=4.478+5.734X+$1.881X^2$(r=0.990) The average number of Artemia nauplius intaken by the larvae was rapidly increased between 15th and 20th day afer hatching, and 9, 212, 242, 750, and 1,171 nauplius were found in the different sizes of larvae, whose total length were 5.65, 6.81, 9.45, 14.96, and 24.52 mm, respectively. 3. Larval growth in total length and body weight reared at four different densites (A: 1.8 $kg/m^3$, B; 4.0 $kg/m^3$, C; 5.0 $kg/m^3$, D; 6.2 $kg/m^3$) indicated that the best growth was found in experiment A, at which the larval were reared at the lower density and the final survival rates extimated were $92.9\%$ in exp. A, $99.5\%$ in exp. C, $89.0\%$ in exp. B, and $88.2\%$ in exp. D. The amount of production per cubic meter turned out to be 30.45 kg in exp. D, 25.89 kg in exp. C, 20.75 kg in exp. B and 10.48 kg in exp. A. therefore, considering both larval growth and survival rate, higher yields seemed to be attainable at the relatively high-rearing density.