• Investigative Magnetic Resonance Imaging
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• v.24 no.3
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• pp.141-153
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• 2020

Purpose: Myocardial T1 and T2 relaxation times are affected by technical factors such as cardiovascular magnetic resonance platform/vendor. We aimed to validate T1 and T2 mapping sequences using a phantom; establish reference T1, T2, and extracellular volume (ECV) measurements using two sequences at 3T in normal Koreans; and compare the protocols and evaluate the differences from previously reported measurements. Materials and Methods: Eleven healthy subjects underwent cardiac magnetic resonance imaging (MRI) using 3T MRI equipment (Verio, Siemens, Erlangen, Germany). We did phantom validation before volunteer scanning: T1 mapping with modified look locker inversion recovery (MOLLI) with 5(3)3 and 4(1)3(1)2 sequences, and T2 mapping with gradient echo (GRE) and TrueFISP sequences. We did T1 and T2 mappings on the volunteers with the same sequences. ECV was also calculated with both sequences after gadolinium enhancement. Results: The phantom study showed no significant differences from the gold standard T1 and T2 values in either sequence. Pre-contrast T1 relaxation times of the 4(1)3(1)2 protocol was 1142.27 ± 36.64 ms and of the 5(3)3 was 1266.03 ± 32.86 ms on the volunteer study. T2 relaxation times of GRE were 40.09 ± 2.45 ms and T2 relaxation times of TrueFISP were 38.20 ± 1.64 ms in each. ECV calculation was 24.42% ± 2.41% and 26.11% ± 2.39% in the 4(1)3(1)2 and 5(3)3 protocols, respectively, and showed no differences at any segment or slice between the sequences. We also calculated ECV from the pre-enhancement T1 relaxation time of MOLLI 5(3)3 and the post-enhancement T1 relaxation time of MOLLI 4(1)3(1)2, with no significant differences between the combinations. Conclusion: Using phantom-validated sequences, we reported the normal myocardial T1, T2, and ECV reference values of healthy Koreans at 3T. There were no statistically significant differences between the sequences, although it has limited statistical value due to the small number of subjects studied. ECV showed no significant differences between calculations based on various pre- and post-mapping combinations.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.31 no.3
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• pp.228-239
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• 1995

A model experiment on the pair midwater trawl net which is prevailing in Denmark is carried out to get the basic data available for Korean pair bottom trawlers. The model net was made in 1/30 scale considering the Tauti's Similarity law of fishing gear and the dimension of experimental tank. The vertical opening, horizontal opening, towing tension and net working depth of the model net were determined in the tank within the towing velocity 0.46~1.15m/sec, front weight 15.5~62.0g and distance between paired boats 5~8m(which correpond to 2~5k't in towing velocity, 70~280kg in weight and 150~240m in distance respectively in the prototype net). The results got from the model experiment can be converted into the full scale net as follows; 1. Vertical opening showed the largest value of 32m at the condition of 2k't in towing velocity, 280kg in front weight and 150m in the distance between paired boats, and the smallest value of 6m at the condition of 5k't in towing velocity, 70kg in front weight and 240m in the distance between paired boats. 2. Horizontal opening showed the largest value of 45m at the condition of 5k't in towing velocity, 70kg in front weight and 240m in the distance between paired boats, and the smallest value of 33m at the condition of 2k't in towing velocity, 280kg in front weight and 150m in the distance between paired boats. 3. Towing tension showed the largest value of 10, 000kg at the condition of 5k't in towing velocity, 280kg in front weight and 240m in the distance between paired boats, and the smallest value of 1, 600kg at the condition of 2k't in towing velocity, 70kg in front weight and 150m in the distance between paired boats. 4. Net working depth showed the largest value of 38m at the condition of 2k't in towing velocity, 280kg in front weight and 150m in the distance between paired boats, and the smallest value of 6m at the condition of 5k't in towing velocity, 70kg in front weight and 240m in the distance between paired boats. 5. Net opening area showed the largest value of 1, 100m super(2) at the condition of 2k't in towing velocity, 280kg in front weight and 180m in the distance between paired boats, and the smallest value of 250m super(2) at the condition of 5k't in towing velocity, 70kg in front weight and 240m in the distance between paired boats.

• The korean journal of orthodontics
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• v.31 no.2 s.85
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• pp.199-207
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• 2001

The segmented TMA T-loop spring, used for reciprocal space closure and described by Burstone, was used to achievebodily movement of canine. Photoelastic analysis is a technique for the transformation of internal stress into visible light patterns. The two-dimensional photoelastic stress analysis was performed, and stress distribution was recorded by photography. The purpose of this study was to visualize photoelastically the distribution of forces transmitted to the alveolus and surrounding structures using new segmented TMA T-loop spring for canine retraction. The results were as follows: 1. Decreased activation produced decreased stress of upper 1st. premolar extraction site and increased intrusive stress of upper 1st. molar, regardless of T-loop position. 2. At 5mm activation, More posterior positioning of T-loop Produced an increased stress in upper 1st. premolar extraction site. 3. At 3mm activation, More posterior positioning of T-loop produced an increased stress in upper 1st. premolar extraction site and mesial lower half of upper 1st. molar mesio-buccal root. 4. At 1mm activation, More anterior positioning of T-loop produced an increased stress in upper mesial and blew apex area of upper canine root. 5. 0.25 B/L ratio and 3mm activation produced bodily movement of canine. To summarize, desired tooth movement and anchorage requirement is possible by altering the activation and mesio-distal position of the T-loop spring.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.799-804
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• 2008

This study was performed to determine physicochemical and sensory quality of low-fat pork loaf containing silkworm powder and vegetable worm (Paecilomyces japonica). Total 2% of fat replacer (soy protein isolate:maltodextrin:$\kappa$-carrageenan:water=1:0.5:0.5:10, w/v) was added. The loaf was separated into CTL (control), T1 (0.2% silkworm powder), T2 (0.2% vegetable worm), T3 (0.4% silkworm powder), T4 (0.4% vegetable worm), T5 (0.1% silkworm powder+0.1% vegetable worm), and T6 (0.2% silkworm powder+0.2% vegetable worm). Pork loaf of T3 showed the highest pH value and cooking loss of pork loaves containing silkworm and vegetable worm was higher than control at day 5. 2-Thiobarbituric acid reactive substances of T2 and T5 showed significantly lower values than control and those additives may reduce lipid oxidation of meat. Overall acceptability was not adversely influenced by silkworm powder and vegetable worm at day 0 and 5. These results indicated that those silkworm powder and vegetable worm could be utilized for pork product industry.

• Journal of the Microelectronics and Packaging Society
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• v.10 no.4
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• pp.9-14
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• 2003

The new optical link receiver with data transfer rate higher than 10Mbps at the supply voltage of 1.8V was designed and fabricated using bipolar technology. The fabricated IC showed the dissipation current of 4.6mA under high level input voltage of 1.5V. The high level output voltage($V_{OH}$) and the low level output voltage($V_{OL}$) were 1.15V and 0V, respectively, for a given 10 Mbps signal which has duty ratio of 50%, $V_{IL}$(low level input voltage) of 0.5V, and $V_{IH}$(high level input voltage) of 1.5V, The duty ratio of output waveform was 52.6%. The rising time(t$_{r}$) and the falling time(t$_{f}$) were 9.5ns and 6.8ns, respectively. The propagation delay difference($t_{PHC}-t_{PLH}$) and the jitter($t_j$) were 11.7ns and 4.3ns, respectively.y.

• Journal of the Korean Applied Science and Technology
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• v.28 no.3
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• pp.273-283
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• 2011

The objective of this study was to determine the feeding effect of a diet containing Cordyceps with fly pupa on the changes in blood lipid profile from broiler chickens, fatty acids and thiobarbituric acid reactive substances (TBARS) in chicken meat. A total of 360 chicks (Ross strain 308) were divided on hatch day into four treated groups with respect to a 35-day feeding regimen: T1 (control group), T2 (2.0% Cordyceps with fly pupa), T3 (3.5% Corceps with fly pupa) and T3 (5.0% Cordyceps with fly pupa). Blood triacylglyceride and total cholesterol level was significantly decreased by 5.32-10.63% and 9.23-12.62%, respectively, in groups T2, T3 and T4 when compared to T1 (p<0.05). Water holding capacity was significantly highest in T2 (p<0.05), while there were no significant differences among groups T2, T3 and T. In chicken meat, the ratio of saturated fatty acid to unsaturated fatty acid was high in the T3 and T4 groups, the ratio of n-6 to n-3 fatty acid was low in the T2, T3 and T4 groups and oleic acid (18:1n-9) was high in the T2, T3 and T4 groups, when compared to T1 (p<0.05). TBARS tended to increase according to the storage time (in days), and was significantly lower in the chicken thigh muscles with skin in groups T2, T3 and T4 as compared to T1 (p<0.05). These results suggest that a diet containing 2.0-3.5% of Cordyceps with fly pupa may decrease blood lipid and improve both the shelf-life and quality of broiler chicken meat.

• Journal of radiological science and technology
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• v.34 no.4
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• pp.271-276
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• 2011

Statistical analysis was performed on the patients who took bone densitometry using Lunar and Hologic equipments for 5 months from January $1^{st}$ 2010 to May $30^{st}$, 2010. Patients consisted of 50 in their 40s, 100 in 50s and 50 in 60s. In addition, the results from bone densitometry were carried out on the same subject with two equipments on the same day. In case of 200 subjects, who received the bone densitometry with two equipments, the average age was 54.5 and 54.4 years old, respectively. There was no difference. The T- score of Lunar equipment was $-1.377{\pm}1.221$ and that of Hologic equipment was $-1.806{\pm}1.123$. The T-score of Lunar equipment was measured higher than that of Hologic equipment. T-test was conducted to determine the equality of the mean of two groups with 200 patients. Since the pvalue was 0.000, the value of bone mineral density was significant in two equipments. Furthermore, the patients, who were diagnosed by Lunar, showed more 'normal' and who were diagnosed by Hologic, showed more osteoporosis, which cartegorized by WHO, such as normal, osteopenia, and osteoporosis. Thus, compared results of bone densitometry on lumbar spine L1 - L4 of four normal people with the same equipment showed that T- score of Lunar equipment was $-0.4{\pm}1.2$, and T- score of Hologic equipment was $-1.1{\pm}1.5$. It showed the higher T- score was measured in Lunar equipment as well. Therefore, the correction factor should be considered to use, since T- scores are different between two equipments.

• The Korean Journal of Mycology
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• v.36 no.1
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• pp.26-30
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• 2008

This study was carried out to develop artificial culture method of Grifola frondosa in polypropylene bag. To find out the favorable substrate formulation of G. frondosa, physicochemical conditions were investigated. The T2 formulation (55 : 25 : 12 : 8) mixing ratio of oak sawdust, oak chip, dried bean-curd refuse and wheat bran showed the shortest time to complete the crop cycle and the highest yield (weight of fresh mushrooms harvested at maturity). Those physicochemical conditions were pH 4.3, 2.4% crude fat contents, 54.1% total carbon, 1.42% total nitrogen, 38.1 C/N ratio, 75.5% porosity and $0.21\;g/cm^3$ bulk density. Among the physicochemical factors, pH, crude fat and total nitrogen may affect mushroom yield. Therefore, development of favorable substrate would be benefit to increase production efficiency of G. frondosa, mushrooms and be commercial potential.

• Journal of Life Science
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• v.13 no.1
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• pp.34-41
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• 2003

The hatching of fertilized egg and early development of larval black seabream, Acanthopngrus schlegeli by immersion of 3,5,3'-triiodo-L-thyronine ($T_3$) with doses of 0.01~0.5 ppm in tank were examined for early development periods and compared with control fish immersed by 0.1 N NaOH and 99% alcohol. Larvae were fed with rotifers for first 5 days during experimental period. Yolk absorption of larvae from $T_3$ immersion groups were significantly faster than that of control. Although hatching times among each groups were not significant difference. the hatching rates of larvae in higher doses (0.1 ppm and 0.5 ppm $T_3$ groups) were significantly lower than control. The results of $T_3$ immersion experiments to newly hatching larvae indicated that exogenous $T_3$induced significant faster the absorption of yolk and oil globule, faster the development of myotome and digestive duct and higher the growth rate of larvae than larvae of control. These results indicate that $T_3$ immersion supplements appear to confer a distinct advantage to eggs and larvae of black seabream, which is in early fragile developmental stage.

• Clinical and Experimental Pediatrics
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• v.45 no.11
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• pp.1368-1372
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• 2002

Purpose : Group A streptococci have a cell wall which consists of M protein and T protein. T protein is known to be helpful in the understanding of the epidemiology of group A streptococci. To study the epidemiologic characteristics, we serotyped T protein of group A streptococci obtained from patients admitted to hospitals, or who visited OPD in five districts of Seoul the during last three years. Methods : Group A streptococci were obtained in five districts in north, northeast, central, northwest and south Seoul from 1998 through 2000. All isolated group A streptococci were serotyped with T protein antisera(Institute of Sera and Vaccine, Prague, Czech Republic). Results : In 1998, analysis of obtained total number of 92 strains revealed that T12, T4, and NT acounted for 72.2%. Among seven cases of scarlet fever, T12 was isolated in four cases and T4 was found in three cases. Two cases of tonsilar abscess produced T8 and NT. One case of cervical lymphadenitis showed T12. In 1999, 41 cases were studied showing that T12, T4, and T1 contributed 68%. Among five cases of scarlet fever, T12 and T4 make up three case. There were two cases of pneumonia(T4 and T1) and one case of cervical lymphadenitis(T8/25). In 2000, the study was performed in four districts except the central area. Among 83 isolates, T12, T4 and T1 accounted for 63.9%. There were three cases of scarlet fever(T12, T4, T5), one case of tonsillar abscess(T12), one case of pneumonia(NT) and one case of sepsis(T1). Conclusion : Serological analysis of T protein of group A streptococci shows no endemic specificity. The yearly pattern reveals that T12 had been decreasing but T1 had shown the opposite trend.