• Journal of Chest Surgery
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• v.42 no.5
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• pp.566-575
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• 2009

Background: The function of a bioprosthetic heart valve is determined largely by the material properties of the valve cusps. The uniaxial tensile test has been studied extensively. This type of testing, however, does not replicate the natural biaxial loading condition. The objective of the present study was to investigate the regional variability of the biaxial strain versus pressure relationship based on the types of fixation liquid models. Material and Method: Porcine aortic valves and pulmonary valves were assigned to three groups: the untreated fresh group, the fixed with glutaraldehyde (GA) group, and the glutaraldehyde with solvent (e.g., ethanol) group. For each group we measured the radial and circumferential stretch characteristics of the valve as a function of pressure change. Result: Radial direction elasticity of porcine aortic and pulmonary valves were better than circumferential direction elasticity in fresh, GA fixed and GA+solvent fixed groups (p=0.00). Radial and circumferential direction elasticity of pulmonary valves were better than aortic valves in GA fixed, and GA+solvent fixed groups (p=0.00). Radial and circumferential direction elasticity of aortic valves were decreased after GA and GA+solvent fixation(p=0.00), except for circumferential elasticity of GA+solvent fixed valves (p=0.785). The radial (p=0.137) and circumferential (p=0.785) direction of elasticity of aortic valves were not significantly different between GA fixed. and GA+solvent fixed groups. Radial (p=0.910) and circumferential (p=0.718) direction of elasticity of pulmonary valve also showed no significant difference between GA fixed and GA+solvent fixed groups. Conclusion: When fixing porcine valves with GA, adding a solvent does not cause a loss of mechanical properties, but, does not improve elasticity either. Radial direction elasticity of porcine aortic and pulmonary valves was better than circumferential direction elasticity.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.32 no.4 s.59
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• pp.233-239
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• 2006

This study was carried out for the evaluation of the effects of emulsion containing the specific antibodies against S. aureus that secreted staphylococcal toxins in atopy dermatitis (AD). The emulsion was formulated to have basic moisturizing effect and the function to inhibit S. aureus colonization and Staphylococcal toxins. The results were as follows; 1. In 19 subjects, 14 subjects (73.7%) showed improvement in SCORAD the mean SCORAD score was improved by 21.87% at week 4 compared to pre-application (p < 0.05). 2. In 17 subjects with severe lesions, 14 subjects(82.35%) showed improvement in SCORAD; the mean SCORAD score was improved by 25.11% at week 4 compared to pre-application (p < 0.05). 3. In 19 subjects, 15 subjects (79%) showed improvement in TEWL; the mean TEWL was improved by 24.32% at week 4 compared to pre-application (p < 0.05). 4. In 17 subjects with severe lesions, 14 subjects (82.35%) showed improvement in TEWL; the mean TEWL was improved by 25.47% at week 4 compared to pre-application (p < 0.05). 5. In 19 subjects, 15 subjects (79%) showed improvement in keratin capacitance; the mean keratin capacitance was improved by 25.01% at week 4 compared to pre-application (P < 0.05). 6. In 17 subjects with severe lesions, 13 subjects (76.47%) showed improvement in keratin capacitance; the mean keratin capacitance was improved by 20.82% at week 4 compared to pre-application (p < 0.05). Based on above-described results, emulsion containing the specific antibodies against S. aureus that secreted staphylococcal toxins is considered to be helpful in the improvement of atopic dermatitis.

• Journal of the Korean Dietetic Association
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• v.8 no.3
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• pp.269-279
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• 2002

To investigate the change of perception after weight management education in elementary, middle and high school students, a survey was conducted. Same questionnaire was administered twice, before and after weight management education, to 426 students at 9 schools in Seoul area. The mean height, weight and body mass index were 145.5$\pm$8.0cm, 40.0$\pm$8.3kg, 18.6$\pm$3.0 for elementary school students, 160.1$\pm$5.2cm, 50.2$\pm$7.3kg, 19.5$\pm$2.4 for middle school students, and 162.2$\pm$5.0cm, 52.2$\pm$6.4kg, 19.8$\pm$2.3 for high school students, respectively. Before education, their preferred weight and perceived healthy weight was 35.4kg and 37.0kg among elementary school students, 44.8kg and 46.5kg among middle school students, and 47.3kg and 48.9kg among high school students, respectively. Differences between their present body weight and their preferred weight and/or perceived healthy weight appeared to be 4.5kg and 2.9kg in elementary school students, 5.6kg and 4.0kg in middle school students, and 5.1kg and 3.3kg in high school students, respectively. After administering education, the differences decreased to 2.5kg and -0.2kg in elementary school students, 4.2kg and 2.7kg in middle school students, and 4.3kg and 2.0kg in high school students, respectively (p<0.01). And their perception on own body shape was investigated using 5 point scale ('too lean' to 'too fat', 1 to 5) before and after education. The mean values changed from 3.1 to 2.8 in elementary school students, from 3.3 to 3.0 in middle school students, and from 3.4 to 3.2 in high school students (p<0.01). Their satisfaction with own body weight was monitored using 5 point scale ('very satisfied' to 'very unsatisfied', 1 to 5), also. The mean values changed from 3.0 to 2.7 in elementary school students, from 3.6 to 3.2, in middle school students, and from 3.8 to 3.4 in high school students (p<0.01). In the evaluation of their nutrition knowledge about weight control using 10 item quiz, before and after education, the mean quiz score was changed from 6.3 to 7.0 in elementary school students, from 7.0 to 7.9 in middle school students, and from 7.5 to 8.1 in high school students (p<0.01). In summary, nutrition education on weight management improved the subject's perception on perceived healthy weight and own body shape, and satisfaction with present body weight. This result suggests that nutrition education program should incorporate strategies to change incorrect beliefs and knowledge regarding weight control. Onto this, weight control education for students should start from their early age, be repeated periodically and consistently, and focus on the harmful effects of excessive weight loss and information on the practical and scientific ways of weight management.

• Journal of Life Science
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• v.25 no.3
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• pp.293-298
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• 2015

Muscle atrophy, known as a sarcopenia, is defined as a loss of muscle mass resulting from a reduction in the muscle fiber area or density due to a decrease in muscle protein synthesis and an increase in protein breakdown. Schisandrae fructus (SF) extract of the fruits of Schisandra chinensis (Turcz) Baillon has been used as a tonic in traditional medicine for thousands of years. Although a great deal of work has been carried out on the therapeutic potential of SF, its pharmacological mechanisms of action in muscle diseases actions remain unclear. In the present study, we investigated the inhibitory effects of SF ethanol extracts on the production of muscle atrophy factors in C2C12 myotubes stimulated with 5-aminoimidazole-4-carboxamide-ribonucleotide (AICAR), an AMP-activated kinase (AMPK) activator, and sought to determine the underlying mechanisms of action. AICAR upregulated atrophy-related ubiquitin ligase muscle RING finger-1 (MuRF-1) and stimulated the levels of the forkhead box O3a (FoxO3a) transcription factor in the C2C12 myotubes. SF supplementation effectively and concentration- dependently counteracted AICAR-induced muscle cell atrophy and reversed the increased expression of MuRF-1 and FoxO3a. Our study demonstrates that SF can reverse the muscle cell atrophy caused by AICAR through regulation of the AMPK and FoxO3a signaling pathways, followed by inhibition of MuRF-1.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.609-617
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• 2000

This study is aimed at investigating an effect of HCl gas on selective reduction of NOx over a CuHM and $V_2O_5-WO_3/TiO_2$ catalyst. SCR process is the most effective method to remove NOx, but catalyst can be deactivated by the acidic gas such as HCl gas which is also included in flue gas from the incinerator. In dry condition of flue gas, the CuHM catalyst treated by HCl gas has shown higher NO removal activity than the fresh catalyst. The activity of the catalyst can be restored by treating at $500^{\circ}C$. On the contrary. $V_2O_5-WO_3/TiO_2$ catalyst is obviously deactivated by HCl and the deactivation increases in proportion to the concentration of HCl gas. The deactivated catalyst is not restored to it's original activity by heat treatment for regeneration. In wet flue gas stream, the CuHM catalyst has shown lower activity than fresh catalyst and $V_2O_5-WO_3/TiO_2$ catalyst was severely deactivated by HCl treatment. The activity loss of catalysts are mainly due to the decrease of Br$\ddot{o}$nsted acid site on the catalyst surface by $NH_3$ TPD. The change of BET surface area of CuHM catalyst after the reaction isn't observed but $V_2O_5-WO_3/TiO_2$ catalyst is observed. The amount of $Cu^{{+}{+}}$ and $V_2O_5$ is decreased after the reaction. From these results, it is expected that CuHM catalyst should be better than $V_2O_5-WO_3/TiO_2$ catalyst for its application to the incineration of flue gas.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.7
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• pp.495-503
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• 2012

The water quality of Gul-po Stream, the subject of this study, has been deteriorating because of the inflow of domestic sewage and the industrial wastewater due to industrialization and the problems relating to the structure of river including slow flow rate and the covering of river. In particular, the domestic sewage from small-medium sized factories by the river and large-scale industrial complex by the upper and middle streams of the river, and the domestic sewage from increasing population due to the regional development are the main pollution sources. Thus, this study aims to survey the water quality and the sediment affecting Gul-po Stream; monitor the state of pollution in water body; assess the yield of sediment and investigate the water quality of river and the problems arising from sediment; and then suggest reasonable ways to improve the situation. The findings from surveying pollution load shows the discharge increases up to average 72.8 times from the upper stream to the downstream of Gul-po Stream, and pollution load increases up to: SS 111 times, BOD 150 times, COD 145 times, the nutrient T-N 222 times and T-P 312 times on an average basis. As for the pollution concentration range, ignition loss is 1.29~12.43%; COD is 4,015~37,547 kg/day; T-N and T-P 94.8~352.5 kg/day and 81.8~372.3 kg/day, respectively. As for the releasing rate of sediment, T-N is -14.46~$156.61mg/m^2/day$; T-P is -11.53~$26.10mg/m^2/day$, indicating the likelihood of internal contamination due to the elution of sediment. This study is expected to be used as basic data to manage Gul-po Stream basin.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.2
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• pp.135-145
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• 2020

Wave observation is widely used to direct observation method for observing the water surface elevation using wave buoy or pressure gauge and remote-sensing wave observation method. The wave buoy and pressure gauge can produce high-quality wave data but have disadvantages of the high risk of damage and loss of the instrument, and high maintenance cost in the offshore area. On the other hand, remote observation method such as radar is easy to maintain by installing the equipment on the land, but the accuracy is somewhat lower than the direct observation method. This study investigates the data quality of MIROS Wave and Current Radar (MWR) installed at Dokdo and improve the data quality of remote wave observation data using the wave buoy (CWB) observation data operated by the Korea Meteorological Administration. We applied and developed the three types of wave data quality control; 1) the combined use (Optimal Filter) of the filter designed by MIROS (Reduce Noise Frequency, Phillips Check, Energy Level Check), 2) Spike Test Algorithm (Spike Test) developed by OOI (Ocean Observatories Initiative) and 3) a new filter (H-Ts QC) using the significant wave height-period relationship. As a result, the wave observation data of MWR using three quality control have some reliability about the significant wave height. On the other hand, there are still some errors in the significant wave period, so improvements are required. Also, since the wave observation data of MWR is different somewhat from the CWB data in high waves of over 3 m, further research such as collection and analysis of long-term remote wave observation data and filter development is necessary.

• Journal of Animal Science and Technology
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• v.46 no.5
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• pp.811-820
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• 2004

Objectives of this study was to determine the comparisons of physico-chemical characteristics in crossbred pigs(Korean native breed ${\times}$ Landrace breed) by feeding periods. A total of 150 pigs were sampled from commercial farm, and assigned into three treatedrnents. Feeding peirods of Tl, T2 and T3 were below 200 days, 220-220 days, over 220 days, respectively. Live weight, carcass weight and backfat thickness were significantly(P<0.05) increased with feeding period increased, and final grade score have significantly(P<0.05) lower when feeding period was increased. pH and water content were significantly(P<0.05) lower when feeding period was increased(over 220days). However, intramuscular fat have no significantly different among the treatments. $L^* and b^* were significantly(P<0.05) lower and a^*$ was significantly higher(P<0.05) when feeding period increased. Cooking loss was higher in the order of Tl > T3 > T2. Shear force values was significantly(P<0.05) decreased by feed period increase. In fatty acids, myristic acid, palmitic acid, stearic acid and saturated fatty acid(SFA) in T2 were significantly(P<0.05) lower in T2, whereas linolenic acid, unsaturated fatty acid(UFA), essential fatty acid(EFA), UFA/SFA and EFA/SFA were significantly higher in T2 compared with other treatment. However palmitoleic acid and arachidonic acid were no significantly different with feeding periods. As a result of this study, crossbred pigs was increased live weight and carcass weight with feeding periods. and improved meat color and tenderness with feeding periods. However, final grade score was decreased with feeding periods

• Journal of the Korean Geotechnical Society
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• v.33 no.11
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• pp.21-34
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• 2017

The ground penetrating radar (GPR) signal can be measured with different amplitudes according to the directivity, so the directivity of the antenna should be considered. The objective of this study is to investigate the directivity of antenna by analyzing the reflection characteristics of electromagnetic waves radiated from the antenna, and to evaluate effective range of angle that can inspect an abnormal area according to the directivity of antenna. For the measurement of the directivity, a circular metal bar is used as reflector and the signals are measured by changing the angle and the distance between reflector and antenna in the E- and H-plane. The boundary distance between the near field and the far field is determined by analyzing the amplitudes of reflected signals, and two points with different distances from each of near and far fields are designated to analyze radiation patterns in near and far fields. As a result of radiation pattern measurement, in the near field, minor lobes are observed at angle section at more than $50^{\circ}$ in both E- and H-plane. Therefore, antenna has the directivity for the direction of main lobe and minor lobes in near field. In the far field, antenna has the directivity for a single direction of main lobe because minor lobes are not observed. The amplitude of the signal reflected from the near field is unstable, but it can be distinguished from noise. Therefore, in the near field, the ground anomaly can be detected with high reliability. On the other hand, the amplitude of the signal reflected from the far field is stable, but it is hard to distinguish between reflected signal and noise because of the excessive loss of electromagnetic wave. The analyses of directivity in the near and the far fields performed in this study may be effectively used to improve the reliability of the analyses of abnormal area.

• Journal of The Korean Ophthalmological Society
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• v.59 no.11
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• pp.1049-1055
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• 2018

Purpose: To investigate the factors associated with glaucoma in patients with pseudoexfoliation syndrome by comparing features of the anterior segments and ocular biometry according to the presence or absence of open-angle glaucoma in pseudoexfoliation syndrome. Methods: We analyzed 96 patients (115 eyes) diagnosed as having pseudoexfoliation syndrome in this study. The patients were divided into two groups of simple pseudoexfoliation syndrome (64 patients, 76 eyes) and pseudoexfoliation glaucoma (32 patients, 39 eyes). We compared the age, sex, underlying disease, location of pseudoexfoliative material, iris change, degree of nuclear cataract, pupil dilatation, corneal endothelial cell counts, central corneal thickness, anterior chamber depth, axial length, corneal curvature, and intraocular pressure (IOP). Results: There were no significant differences between the two groups in terms of age (p = 0.694), sex (p = 0.161), diabetes (p = 0.440), hypertension (p = 0.238), pseudoexfoliative material observed in anterior capsule (p = 0.700), pupillary margin (p = 0.210), iris depigmentation (p = 0.526), pupillary ruff loss (p = 0.708), degree of nuclear cataract (p = 0.617), pupil dilatation (p = 0.526), central corneal thickness (p = 0.097), anterior chamber depth (p = 0.283), axial length (p = 0.095), or horizontal and vertical corneal curvature (p = 0.066 and 0.306, respectively). In pseudoexfoliation glaucoma, significantly higher IOP (p = 0.026), a high frequency of membrane formation (p = 0.047), and decreased corneal endothelial cell counts (p = 0.048) were observed. Conclusions: Pseudoexfoliation syndrome with open-angle glaucoma was shown to be associated with high IOP, decreased corneal endothelial cell counts, and a high frequency of membrane formation. Therefore, when such changes are observed in pseudoexfoliation syndrome patients, a higher risk of open-angle glaucoma should be recognized, and careful attentionis required accordingly.