• The Journal of Korean Academy of Prosthodontics
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• v.39 no.4
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• pp.351-365
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• 2001

For accurate impression taking, accurate impression material, solid individual tray, and bond strength between impression materials and resin tray are important factors. The purpose of this study was to evaluate tensile bond strength of rubber impression materials to various tray resin materials. This study tested the time dependent tensile bond strength between commercial brands or poly ether, polysulfide, additional silicone impression materials and commercial brands of self curing tray resin. light activited tray resin when applying adhesive Resin specimens were made with 20mm in diameter, 2mm in thickness. 1 made total 360 specimens, 10 per each group and the tensile bond strength was measured by using the Instron($M100EC^{(R)}$, Mecmesin Co., England). The results were as follows ; Comparisons of various impression materials. 1. In case of Impregum $F^{(R)}$, the bond strength of tray resin was decreased in order of SR $Ivolen^{(R)}$, Ostron $100^{(R)}$ Instant tray $mix^{(R)}$, $Lightplast^{(R)}$. All groups excluding Ostron $100^{(R)}$, Instant tray $mix^{(R)}$ are significant difference (p<0.05). Drying time after applying adhesive, the tensile bond strength of tray resin was insignificantly decreased in order of 10 min drying time group. 1 min drying time group. 5 min drying time group. 2. In case of Permlastic $regular^{(R)}$ the bond strength of tray resin was insignificantly decreased in order of Ostron $100^{(R)}$. SR $Ivolen^{(R)}$, Instant tray $mix^{(R)}$ $Lightplast^{(R)}$. About drying time after applying adhesive, the tensile bond strength of tray resin was significantly decreased in order of 5 min drying time group, 10 min drying time group, 1 min drying time group(p<0.05). 3. In case of Exaflex $regular^{(R)}$. the bond strength of tray resin was decreased in order of $Lightplast^{(R)}$, SR $Ivolen^{(R)}$, Instant tray $mix^{(R)}$, Ostron $100^{(R)}$. $Lightplast^{(R)}$ was significant difference(p<0.05). About drying time after applying adhesive, the tensile bond strength of tray resin was decreased in order of 5 min drying time group, 10 min drying time group, 1 min drying time group(p<0.05). Especially 5 min ding time group was significant difference(p<0.05). According to the results of this study, we can see the greatest tensile bond strength when using Impregrm $F^{(R)}$ and Permlastic $regular^{(R)}$ with self curing tray resin, when using Exaflex $regular^{(R)}$ with light activated tray resin In my opinion, adhesive should be dried more than 5 min before impression taking to achieve the greatest tensile bond strength.

• Investigative Magnetic Resonance Imaging
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• v.5 no.2
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• pp.116-122
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• 2001

Purpose : To find sensitivity of MRI imaging methods to slow flow phantom study was performed with conventional Spin-Echo, gradient echo based Phase Contrast, fast GRASS, and heavily T2-weighted Fast Spin Echo pulse sequences. Materials and Methods : A siphon driven flow phantom was constructed with a ventriculo-peritoneal shunt catheter and a GE phantom to achieve continuous variable flow. Four different pulse sequences including Spin-Echo, Phase Contrast, GRASS and Heavily T2-weighted Fast Spin Echo were evaluated to depict slow flow in the range from 0.08 ml/min to 1.7 ml/min and to compare signal intensities between static fluid and flowing fluid. Results : In the slow flow above 0.17 ml/min conventional Spin-Echo showed superior apparent contrast between static and flowing fluid while GRASS was more sensitive to the very slow flow below 0.17 ml/mim. It was not accurate to calculate flow and velocity below 0.1 ml/min with a modified PC imaging. Conclusion : Four different MR pulse sequences demonstrated different sensitivity to the range of slow flow from 0.08 ml/min to 1.7 ml/min. This finding may be clinically useful to measure CSF shunt flow or detecting CSF collection and thrombosis.

• Food Science and Preservation
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• v.12 no.2
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• pp.166-172
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• 2005

Response surface methodology (RSM) was applied to monitor the effects of steaming and roasting conditions of Polygonatum odoratum roots an total phenolics content, electron donating ability (EDA) and nitrite-scavenging ability (NSA) of the extract. In steaming and roasting processes based on the central composite design. with variations in steaming time $(60\~180\;min)$, roasting temperature $(110\~150\;min)$ and roasting time $(10\~50\;min)$, coefficients of determinations $(R^2)$ were 0.9356 (p<0.01) in total phenolics, 0.9578 (p<0.01) in EDA and 0.9436 (p<0.01) in NSA (pH 3.0). The maximum value of total phenolics was $2847.67\;mg\%$ at 135.59 min of steaming time, $143.84^{\circ}C$ of roasting temperature and 43.47 min of roasting time. The maximum value of EDA was $75.00\%$ in 108.98 min, $135.56^{\circ}C$ and 48.86 min. The maximum value of NSA (pH 3.0) was $87.38\%$ in 162.80 min, $143.88^{\circ}C$ and 31.97 min, respectively. Total phenolics content of the extract was influenced by heating conditions in the order of roasting temperature, steaming time and roasting time. While EDA and NSA were appreciably influenced by roasting time, followed by roasting temperature and steaming time.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.1
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• pp.64-70
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• 1996

Kinetic properties of typsins purified from dark-fleshed fish (anchovy, mackerel, yellowfin tuna, and albacore) were examined and analyzed on $benzoyl-_{D,L}-arginine-p-nitroanilide\;(BAPNA)$. The values of Km' and $k_{cat}$ of the purified trypsins from the four dark-fleshed fish were found to be $49.3{\mu}M$ and $90.9\;min^{-1}$ for anchovy, $53.7{\mu}M$ and $61.2min-^{-1}$ for mackerel A, $96.5{\mu}M$ and $76.6min^{-1}$ for mackerel B, $62.8{\mu}M$ and $46.6min^{-1}$ for yellowfin tuna, and $98.3{\mu}M$ and $47.7min^{-1}$ for albacore, respectively. The values of $K_i$ on $tosyl-_L-lysine$ chloromethyl ketone (TLCK) were determined to be $20.90{\mu}M$ for anchovy trypsin, $2.86{\mu}M$ for mackerel trypsin A, $3.90{\mu}M$ for mackerel trypsin B, $0.96{\mu}M$ for yellowfin tuna trypsin, and $1.82{\mu}M$ for albacore trypsin. Thus yellowfin tuna trypsin was the most sensitive to TLCK among all trypsins. The activities and catalytic efficiency of the trypsins purified from the temperate zone fish, anchovy and mackerel, were higher than those of the trypsins purified from yellowfin tuna and albacore which migrate widely from the tropic zone to the temperate zone.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.678-681
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• 1999

The objective of this study was to evaluate the effect of different heating rates on the thermal properties of pork loin muscle by DSC. Pork loin muscle was subjected to programmed heating at the following heating rate: 5, 10, 20, 30 and $40^{\circ}C/min$. Peaks were progressively shifted to right side as the heating rate was increased. $T_0$ was $50.39^{\circ}C$ at $5^{\circ}C/min$ and it was increased to $57.45^{\circ}C$ at $40^{\circ}C/min$ (p<0.05). Total enthalpy was 3.52 J/g at $5^{\circ}C/min$ and total enthalpy was increased to 3.60, 4.14, 4.54 and 4.61 J/g by degrees at heating rate 10, 20, 30 and $40^{\circ}C/min$ respectively.

• Food Science and Preservation
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• v.15 no.1
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• pp.66-73
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• 2008

Response surface methodology (RSM) was applied for monitor the yields of desirable substances from fig (Ficus carica L) under different extraction conditions. The maximum yield was 66.46% at 22.08 mL/g of solvent to sample ratio, $90.59^{\circ}C$ extraction temperature and 148.04 min extraction time. The maximum total phenolics was $121.31{\mu}g/mL$ at 17.87 mL/g, $98.82^{\circ}C$, and 130.80 min. The maximum electron donating ability was 54.09% at $121.31{\mu}g/mL$, 18.13 mL/g, and $98.81^{\circ}C$. The maximum value of protease activity was 54.51 unit/min at 17.45 mL/g, $99.01^{\circ}C$, and 131.43 min. In addition, the maximum value of reducing sugar content was 19.14 mg/mL in 22.66 mL/g, $86.30^{\circ}C$, and 153.59 min. The optimum conditions estimated by RSM for maximal extraction of the effective components were $17{\sim}25$ mL/g of solvent to sample ratio, $80{\sim}100^{\circ}C$ of extraction temperature, and $100{\sim}170$ min of extraction time.

• The Korean Journal of Physiology
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• v.30 no.1
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• pp.43-51
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• 1996

This study was aimed to elucidate the changes in heart rate variability during treadmill exercise at various speeds and grades by spectral analysis. Thirty-three untrained male college students aged $20{\sim}26\;yr $were employed to exercise on a treadmill using 4 speeds (4.02, 5.47, 6.76 and 8.05 km/h) and 6 grades (0, 4, 8, 12, 16 and 20%). A fixed speed was selected for each session with the grade increased every 3 min. The electrocardiogram, respiration and the stepping activity were continuously recorded through an A/D converter system on the computer disk. Power spectra of heart rate variability (RRV) were obtained by use of a fast Fourier transform algorithm. The frequency domain was divided into 3 bands: $VLF\;(0{\sim}0.04\;Hz),\;LF\;(0.04 {\sim}0.15\;Hz)\;and\;HF\;(0.15{\sim}1.00\;Hz).$ Heart rate was $74.4{\pm}2.1\;beats/min$ at rest and showed a steady increase during treadmill exercise with increasing speed and grade up to $196.7{\pm}5.0\;beats/min.$ Total power of HRV was $35.0{\pm}6.7\;(beats/min)^{2}$ at rest and progressively decreased during exercise down to $1.9{\pm}0.3\;(beats/min)^{2}.$ The %VLF power of HRV was $34.5{\pm}3.7\; %$ at rest and showed no significant change during exercise except for a decrease observed at the highest intensity of exercise. The %LF power was $44.1{\pm}3.0\;%$ at rest and showed a progressive decrease down to $4.5{\pm}1.0\;%$ during those stages of exercise where heart rate was over 135 beats/min. The %HF power was $21.4{\pm}2.9\;%$ at rest and showed a progressive increase up to $87.1{\pm}6.7\;%$ during higher intensity exercise where heart rate was over 165 beats/min. Peak frequency of HF band was $0.200{\pm}0.018\;Hz$ at rest and was shifted to higher frequencies up to $0.909{\pm}0.048\;Hz$ at heart rates greater than 135 beats/min. Respiratory frequency was $18.0{\pm}1.5$ breaths/min at rest and significantly increased during exercise up to $53.0{\pm}3.7$ breaths/min. Stride frequency during treadmill exercise showed an increasing tendency with increasing speed from $55.6{\pm}0.9$ steps/min at 4.02 km/h to $81.2{\pm}0.6$ at 8.05 km/h. It was concluded that total power of HRV decreased progressively with increasing exercise intensity due to the withdrawal of parasympathetic activity. At higher exercise intensity, % LF power decreased and %HF power increased with its peak frequency shifted to higher values in a progressive mode with increasing speed and grade, reflecting a readjustment in the cardiovascular system and the increased respiration and its rate, respectively.

• Journal of Embryo Transfer
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• v.18 no.1
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• pp.51-59
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• 2003

This study was carried out to evaluate the effect of different freezing and thawing rates on the viability, motility and acrosomal changes of frozen canine spermatozoa. The ejaculated semen was extended with Tris-egg yolk buffer containing 8% glycerol and equilibrated for 60 min after cooled to 4$^{\circ}C$ for 58 min. The straws were cryopreserved gradually by slow-cooling at different distance(6, 10 and 17 cm, respectively) from the liquid nitrogen (L$N_2$) to achieve temperature rate of 3, 8.9 and 19$^{\circ}C$ /min. Thawing of the straws was performed in a water bath fur 2 min at 37$^{\circ}C$ and 55$^{\circ}C$ , respectively. The motility of frozen-thawed spermatozoa was assessed by phase-contrast microscopy. To assess their viability and acrosome content, spermatozoa were stained with a vital stain and Fluorescence conjugated lectin Pisum Savitum Agglutinin (FITC/PAS), respectively. Concentration of the ejaculated fresh semen was normal range of 3.44 $\times$ 10$^{8}$ /ml. Freezing temperature were reduced to -110, -70 and -35$^{\circ}C$, as higher distance from liquid nitrogen, 6, 10 and 17 cm, respectively. Freezing at 3$^{\circ}C$/min in distance of 17 cm from liquid nitrogen yielded better motility, viability and rate of intact acrosome than 8.9 or 19$^{\circ}C$/min and the optimal thawing was 37$^{\circ}C$ for 2 min.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.2
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• pp.149-153
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• 1993

Daily energy expenditures (DEE) of 82 co-eds in a University were estimated simultaneously by use of calorie counter and 15-min check list diary for 3 days, including a weekend day. The results are summarized as follows. The mean values of DEE from 15-min check list diary and calorie counter were 1967kcal and 1649kcal, respectively. DEE obtained with 15-min check list diary seems to be consistent with the results made by others concerning DEE of college female in Korea, but DEE by calorie counter was lower than that. However, DEE by calorie counter show high correlations with anthropometric indices of subjects and DEE by 15-min check list diary. Therefore, DEE by 15-min check list diary was taken as standard and regression equation for predicting DEE of subjects were developed: DEE by 15-min check list diary =3.31186 + 1.18837 $\times$ DEE by calorie counter. This technique for measuring DEE permits us to have more accurate estimate of DEE and acceptable to the subjects. When the subjects classified as underweight, normal, overweight according to relative body weight(RBW), DEE and DEE per kg of body weight were significantly different from each other between three groups based on RBW. The frequency of 15-minute periods with a categorical value of 1 was significantly higher in overweight than underweight and normal groups and the frequency of a categorical value 3 was significantly lower in overweight than underweight group. From the results shown above, physical activity level of overweight group was lower than that of normal and underweight groups.

• (The)Study of the Eastern Classic
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• no.69
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• pp.509-530
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• 2017

The purpose f this thesis is to examine the reality of Min Sha-pyeong, which led to life in the end of the Koryo Dynasty. Min Sha-pyeong was able to conduct academic exchanges through active negotiations with various scholars at the time. After passing the civil service exam at the age of 21, Min Sha-pyeong acted in various positions and remained loyal to the government. Min Sha-pyeong, who frequently met with Lee Je-hyun, Baek Mun-bo and Lee-saek, exchanged opinions. Sometimes Baek Mun-bo gathered together and always joined him when drinking. Lee-saek was convinced that his poetry would continue to inspire. The time when Min Sha-pyeong was active very confusing at home and abroad. In the end of the Koryo Dynasty, the national operating system was unstable due to the poor land and the suffering of the afflicted people, who suffered from frequent in vasions of Japan. At the time, the corruption and the suffering of the people were serious. Min Sha-pyeong refers to the reality of the people who love the people, reflecting the lives of the people living in poverty. Min Sha-pyeong thinks life without loyality is not a normal life. If I had a desire, I realized that the riches of wealth would wane someday. Min Sha-pyeong hoped that he would be relieved of his sympathy and would be relieved of their position in sympathy ith the people. Here, youy can see the reality of the people in Min Sha-pyeong is clearly revealed.