• Food Science of Animal Resources
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• v.30 no.3
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• pp.487-494
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• 2010

Cooked pork can be easily contaminated with Staphylococcus aureus during carriage and serving after cooking. This study was performed to develop growth prediction models of S. aureus to assure the safety of cooked pork. The Baranyi and Gompertz primary predictive models were compared. These growth models for S. aureus in cooked pork were developed at storage temperatures of 5, 15, and $25^{\circ}C$. The specific growth rate (SGR) and lag time (LT) values were calculated. The Baranyi model, which displayed a $R^2$ of 0.98 and root mean square error (RMSE) of 0.27, was more compatible than the Gompertz model, which displayed 0.84 in both $R^2$ and RMSE. The Baranyi model was used to develop a response surface secondary model to indicate changes of LT and SGR values according to storage temperature. The compatibility of the developed model was confirmed by calculating $R^2$, $B_f$, $A_f$, and RMSE values as statistic parameters. At 5, 15 and $25^{\circ}C$, $R^2$ was 0.88, 0.99 and 0.99; RMSE was 0.11, 0.24 and 0.10; $B_f$ was 1.12, 1.02 and 1.03; and $A_f$ was 1.17, 1.03 and 1.03, respectively. The developed predictive growth model is suitable to predict the growth of S. aureus in cooked pork, and so has potential in the microbial risk assessment as an input value or model.

• Journal of Internet of Things and Convergence
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• v.6 no.4
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• pp.7-14
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• 2020

This study analyzed the effect of the number of deaths of circulatory system diseases according to 12-day short-term exposure of carbon monoxide from January 2010 to December 2018, and predicted the future treatment cost of circulatory system diseases according to increased carbon monoxide concentration. Data were extracted from Air Korea of Korea Environment Corporation and Korea Statistical Office, and analyzed using Poisson regression analysis and ARIMA intervention model. For statistical processing, SPSS Ver. 21.0 program was used. The results of the study are as follows. First, as a result of analyzing the relationship between the impact of short-term carbon monoxide exposure on death of circulatory system diseases from the day to the previous 11 days, it was found that the previous 11 days had the highest impact. Second, with the increase in carbon monoxide concentration, the future circulatory system disease treatment cost was estimated at 10,123 billion won in 2019, higher than the observed value of 9,443 billion won at the end of December 2018. In addition, when summarized by month, it can be seen that the cost of treatment for circulatory diseases increases from January to December, reflecting seasonal fluctuations. Through such research, the future for a healthy life for all citizens can be realized by distributing various devices and equipment utilizing IoT to preemptively respond to the increase in air pollutants such as carbon monoxide.

• Journal of Korean Neurosurgical Society
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• v.64 no.5
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• pp.791-798
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• 2021

Objective : The period of mechanical ventilator (MV)-dependent respiratory failure after cervical spinal cord injury (CSCI) varies from patient to patient. This study aimed to identify predictors of MV at hospital discharge (MVDC) due to prolonged respiratory failure among patients with MV after CSCI. Methods : Two hundred forty-three patients with CSCI were admitted to our institution between May 2006 and April 2018. Their medical records and radiographic data were retrospectively reviewed. Level and completeness of injury were defined according to the American Spinal Injury Association (ASIA) standards. Respiratory failure was defined as the requirement for definitive airway and assistance of MV. We also evaluated magnetic resonance imaging characteristics of the cervical spine. These characteristics included : maximum canal compromise (MCC); intramedullary hematoma or cord transection; and integrity of the disco-ligamentous complex for assessment of the Subaxial Cervical Spine Injury Classification (SLIC) scoring. The inclusion criteria were patients with CSCI who underwent decompression surgery within 48 hours after trauma with respiratory failure during hospital stay. Patients with Glasgow coma scale 12 or lower, major fatal trauma of vital organs, or stroke caused by vertebral artery injury were excluded from the study. Results : Out of 243 patients with CSCI, 30 required MV during their hospital stay, and 27 met the inclusion criteria. Among them, 48.1% (13/27) of patients had MVDC with greater than 30 days MV or death caused by aspiration pneumonia. In total, 51.9% (14/27) of patients could be weaned from MV during 30 days or less of hospital stay (MV days : MVDC 38.23±20.79 vs. MV weaning, 13.57±8.40; p<0.001). Vital signs at hospital arrival, smoking, the American Society of Anesthesiologists classification, Associated injury with Injury Severity Score, SLIC score, and length of cord edema did not differ between the MVDC and MV weaning groups. The ASIA impairment scale, level of injury within C3 to C6, and MCC significantly affected MVDC. The MCC significantly correlated with MVDC, and the optimal cutoff value was 51.40%, with 76.9% sensitivity and 78.6% specificity. In multivariate logistic regression analysis, MCC >51.4% was a significant risk factor for MVDC (odds ratio, 7.574; p=0.039). Conclusion : As a method of predicting which patients would be able to undergo weaning from MV early, the MCC is a valid factor. If the MCC exceeds 51.4%, prognosis of respiratory function becomes poor and the probability of MVDC is increased.

• Journal of the Korean Institute of Gas
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• v.25 no.6
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• pp.35-44
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• 2021

The PR (Photo Resist) process in the semiconductor process is a process that uses a mixture of flammable substances. Due to the process equipment is installed in a clean room and when flammable substances leak, there is a high risk of suffocation, fire, and explosion. It is necessary to analyze the impact of accidents that may occur during operation and to evaluate whether the safety of workers can be guaranteed. In this study, the value of radiant heat and temperature change at the monitor point set up virtual inside the clean room was confirmed through CFD simulation of 10 leak and fire scenarios using the FLACS CFD - Fire Module. A fire that occurs inside a clean room transfers high radiant heat to the inter-story structure, but its scope is quite limited, and it is unlikely that it will collapse in a single fire accident. There was no scenario in which two stairs leading to the exit were exposed to high radiant heat at the same time due to a fire accident, therefore workers were able to escape in case of a fire. In addition, it was confirmed that the level of radiant heat and temperature rise rapidly decreased as they moved downstairs. According to the API 520 standard, workers exposed to 6.31 kW/m² of radiant heat that workers can withstand for 30 seconds were confirmed that it was possible to sufficiently escape from the inside.

• Journal of dental hygiene science
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• v.22 no.1
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• pp.20-29
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• 2022

Background: The purpose of this study is to investigate the effect of liquefied digestive medicines on the composite resin surface. Methods: Three types of liquefied digestive medicines (Gashwalmyeongsu, Wicheongsu, and Saengrokcheon) were selected as experimental groups, Samdasoo and Chamisul as negative controls, and Trevi as positive controls were selected to measure pH and titratable acidity. The samples filled with resin at acrylic were made total 300, 50 per group. To evaluate the erosion risk of the composite resin, the specimens were immersed in a liquefied medicine for 1, 3, 5, 15, and 30 minutes, and then the surface microhardness was measured using the Vickers Hardness Number, and the surface change was observed with scanning electron microscope (SEM). Results: The average pH of the three liquefied medicine was 3.75±0.30, the Saengrokcheon was the lowest at 3.45±0.01, and the Trevi was 4.66 and Samdasoo and Chamisul were 7.40 and 8.58, respectively. The amount of NaOH reaching pH 5.5 and 7.0 was the lowest in the order of Trevi, Gashwalmyeongsu, Wicheongsu, and Saengrokcheon. The largest surface hardness reduction value was shown in Gashwalmyeongsu (-11.85±3.73), followed by Saengrokcheon (-9.79±3.11) and Wicheongsu (-8.28±2.83), and Samdasoo (-0.84±1.56) and Chamisul (-6.24±0.42) had relatively low surface hardness reduction values. However, Trevi (-16.67±5.41), a positive control group containing carbonic acid, showed a higher decrease in surface hardness than the experimental group. As a result of observation with SEM, experimental group and positive control group, showed rough surfaces and irregular cracks, and negative control groups showed smooth patterns similar to before immersion. Conclusion: The liquefied digestive medicine with low pH could weaken the composite resin surface, and the carbonic acid component could more effect on the physical properties of the composite resin than pH.

• The Journal of Korean Society for Radiation Therapy
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• v.27 no.1
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• pp.45-52
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• 2015

Purpose : The dose distribution of organ at risk (OAR) and normal tissue is affected by treatment technique in postoperative radiation therapy for prostate cancer. The aim of this study was to compare dose distribution characteristic and to evaluate treatment efficiency by devising VMAT plans according to applying differed number of arc and IMRT plan for postoperative patient of prostate cancer radiation therapy using a rectal balloon. Materials and Methods : Ten patients who received postoperative prostate radiation therapy in our hospital were compared. CT images of patients who inserted rectal balloon were acquired with 3 mm thickness and 10 MV energy of HD120MLC equipped Truebeam STx (Varian, Palo Alto, USA) was applied by using Eclipse (Version 11.0, Varian, Palo Alto, USA). 1 Arc, 2 Arc VMAT plans and 7-field IMRT plan were devised for each patient and same values were applied for dose volume constraint and plan normalization. To evaluate these plans, PTV coverage, conformity index (CI) and homogeneity index (HI) were compared and $R_{50%}$ was calculated to assess low dose spillage as per treatment plan. $D_{25%}$ of rectum and bladder Dmean were compared on OAR. And to evaluate the treatment efficiency, total monitor units(MU) and delivery time were considered. Each assessed result was analyzed by average value of 10 patients. Additionally, portal dosimetry was carried out for accuracy verification of beam delivery. Results : There was no significant difference on PTV coverage and HI among 3 plans. Especially CI and $R_{50%}$ on 7F-IMRT were the highest as 1.230, 3.991 respectively(p=0.00). Rectum $D_{25%}$ was similar between 1A-VMAT and 2A-VMAT. But approximately 7% higher value was observed on 7F-IMRT compare to the others(p=0.02) and bladder Dmean were similar among the all plan(P>0.05). Total MU were 494.7, 479.7, 757.9 respectively(P=0.00) for 1A-VMAT, 2A-VMAT, 7F-IMRT and at the most on 7F-IMRT. The delivery time were 65.2sec, 133.1sec, 145.5sec respectively(p=0.00). The obvious shortest time was observed on 1A-VMAT. All plans indicated over 99.5%(p=0.00) of gamma pass rate (2 mm, 2%) in portal dosimetry quality assurance. Conclusion : As a result of study, postoperative prostate cancer radiation therapy for patient using a rectal balloon, there was no significant difference of PTV coverage but 1A-VMAT and 2A-VMAT were more efficient for dose reduction of normal tissue and OARs. Between VMAT plans. $R_{50%}$ and MU were little lower in 2A-VMAT but 1A-VMAT has the shortest delivery time. So it is regarded to be an effective plan and it can reduce intra-fractional motion of patient also.

• Journal of Society of Preventive Korean Medicine
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• v.18 no.2
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• pp.11-30
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• 2014

Objective : To compare the differences in health behaviors by chronic diseases of middle-aged living in Seoul's low-income housing Method : Of the 1469 residents aged 35 to 60 living in low-income housing in Seoul's District A, 318 were equal probability of selection method selected. t-test, ANOVA, $x^2$, OR(95% CI, P-value) were selected to analyze the data, and the confidence interval was 5%. Results : There were no significant differences in all health behaviors by vascular and metabolic, But there was a statistically significant difference for gastrointestinal diseases caused by sleep hours(p=0.001), liver diseases caused by smoking, drinking and sleep hours(p=0.004, p=0.001, and p=0.033, respectively), musculoskeletal diseases caused by sleep hours and health exam(p=0.0000 and p=0.002, respectively). Also, statistically significant differences were found for tumors caused by sleep hours(p=0.004), depression by the sleep hours and health exam(p=0.001 and p=0.013, respectively), allergies by in sleep hours(p=0.004), thyroid diseases by smoking and health exam(p=0.013 and p=0.007, respectively). After adjusting for the confounding factors for diseases, OR was obtained for each health behavior. There were no statistically significant differences in all health behaviors for vascular, metabolic, and tumors. However, the OR for gastrointestinal diseases 4.10(1.63-10.36, 0.0028) and 2.96(1.05-8.41, 0.0041) at 5-7 and 7-9 sleep hours. The OR for liver diseases was 3.13(1.03-9.48, 0.0437) at 7-9 sleep hours, the OR values for musculoskeletal diseases were 2.91(1.23-6.88, 0.00149), and 4.46(1.68-11.86, 0.0027) at 5-7 and 7-9 sleep hours. OR for depression were 4.82(1.70-13.66, 0.0031) and 4.13(1.19-14.31, 0.0026) at 5-7 and 7-9 sleep hours. OR for allergy were 2.78(1.22-6.32, 0.0015) and 3.93(1.49-10.39, 0.0058) at 5-7 and 7-9 sleep hours. There were statistical significances for liver diseases for 1-2 times of health exam at 0.35(0.14-0.90, 0.00301), for liver diseases for 1-2 times of health exam at 0.35(0.14-0.90, 0.00301), for musculoskeletal diseases for 3-4 times of health exam at 0.26(0.09-0.79, 0.0175), for depression for 3-4 times of health exam at 0.17(0.04-0.66, 0.0106), for allergies for 1-2 times of health exam at 0.30(0.13-0.70, 0.0055), and for thyroid diseases for 1-2 times and annually of health exam at 0.07(0.01-0.60, 0.00154), 0.09(0.01-0.96, 0.0461). We known significant difference the health behaviors by the diseases. especially in sleep hours and health exam times Conclusion : Only sleep hours and health exam caused statistically significant differences in chronic diseases. but the sleep hours was postitively correlated with the risk of disease, while health exam were inversely related.

• Journal of the Korean Society of Radiology
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• v.5 no.5
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• pp.303-308
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• 2011

Background/Aims : The increasing use of diagnostic and therapeutic interventional radiology calls for greater consideration of radiation exposure risk to radiologist and radiological technician, and emphasizes the proper system of radiation protection. This study was designed to assess the effect of a protective grass shield. Methods : A protective grass was following data depth, 0.8 cm; width, 100 cm; length, 100 cm, lead equivalent, 1.6 mmPb. The protective shield was located between the patient and the radiologist. Thirty patients (13 male and 17 female) undergoing interventional radiology between September 2010 and December 2010 were selected for this study. The dose of radiation exposure was recorded with or without the protective grass shield at the level of the head, chest, and pelvis. The measurement was made at 50 cm and 150 cm from the radiation source. Results : The mean patient age was 69 years. The mean patient height and weight was $159.7{\pm}6.7$ cm and $60.3{\pm}5.9$ kg, respectively. The mean body mass index (BMI) was $20.5{\pm}3.0$ kg/m2. radiologists received $1530.2{\pm}550.0$ mR/hr without the protective lead shield. At the same distance, radiation exposure was significantly reduced to $50.3{\pm}85.2$ mR/hr with the protective lead shield (p-value<0.0001). The radiation exposure to radiologist and radiological technician was significantly reduced by the use of a protective lead shield (p value <0.0001). The amount of radiation exposure during interventional radiology was related to the patient' BMI (r=0.749, p=0.001). Conclusions : This protective shield grass is effective in protecting radiologist and radiological technician from radiation exposure.

• Pediatric Infection and Vaccine
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• v.17 no.2
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• pp.169-176
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• 2010

Purpose : We aimed to evaluate predictive parameters for non-response to intravenous immunoglobulin (IVIG) in patients with Kawasaki disease (KD) before IVIG use using two controls. Methods : We evaluated 229 consecutive KD patients who were treated with 2 g/kg of IVIG at a single center. Those who had persistent fever >24 hours after IVIG infusion made up the 23 IVIG non-responders; the first control included a total 206 defervesced cases and the second control included 46 cases that were matched for age and pre-treatment fever duration to non-responders. Results : Demographic and clinical characteristics were similar in IVIG non-responders and responders at presentation. As for laboratory findings, the neutrophil differential, CRP, AST, ALT, and LDH were higher, and lymphocyte differential, total protein, albumin, platelet count, and total cholesterol were significantly lower in IVIG non-responders compared to responders by univariate analysis in both study designs. However in multivariate analysis, non-responders showed a significantly higher neutrophil differential (cutoff value, >77%, sensitivity 68.4% and specificity 79.5%) and lower cholesterol (<124 mg/dL, sensitivity 79% and specificity 70.5%). Whereas plasma albumin (<3.6 g/dL, sensitivity 73.7% and specificity 60%) was the sole laboratory parameter of non-responders in the second study design. Conclusion : Severity of inflammation in KD was reflected by higher or lower laboratory values at presentation. Because the multivariate analysis for these indices may be influenced by some confounding factors, including the numbers of patients of different ages and fever duration, other assessment modalities are needed for KD patients with the greatest risk of coronary artery lesions.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2007.11a
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• pp.79-92
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• 2007

Oxidative stress have known to be a risk factor for the degenerative processes and closely related to a lot of diseases. It is well established that antioxidants are good in protection and therapeutic means against oxidative damage. There is increasing interest in natural antioxidants and many natural antioxidants have been found and utilized as the possible protection for various diseases and skin aging. We have screened natural antioxidant agents for cosmeceuticals, nutraceuticals, and drugs as therapeutic and preventive means against oxidative stress, and have developed a number of novel antioxidants from various natural sources. A novel melanin synthesis inhibitor, Melanocin A, isolated from the metabolite of a fungal strain Eupenicillium shearii F80695 inhibited mushroom tyrosinase and melanin biosynthesis of B16 melanoma cells with $IC_{50}$ value of 9.0 nM and MIC value of $0.9\;{\mu}M$, respectively. Melanocin A also exhibited potent antioxidant activity by scavenging of DPPH and superoxide anion radicals. UV was found to increase the level of hydrogen peroxides and other reactive oxygen species (ROS) in skin tissues. This increase in ROS may not only alter the structure and function of many genes and proteins directly but may also modulate their expressions through signal transduction pathways and, ultimately, lead to skin damage. We investigated the effect of Melanocin A on UV-induced premature skin aging. Firstly, the effect of Melanocin A on UV-induced matrix metalloproteinase (MMP)-9 expression in an immortalized human keratinocyte cell line, HaCaT in vitro was investigated. Acute UV irradiation induced MMP-9 expression at both the mRNA and protein levels and Melanocin A suppressed this expression in a dose-dependent manner. We then investigated UV-induced skin changes in hairless mice in vivo by Melanocin A. Chronic exposure of hairless mouse dorsal skin to UV increased skin thickness and induced wrinkle formation and the gelatinase activities of MMP-2 and MMP-9. Moreover, Melanocin A significantly suppressed UV-induced morphologic skin changes and MMP-2 and MMP-9 expression. These results show that Melanocin A can prevent the harmful effects of UV that lead to skin aging. Therefore, we suggest that Melanocin A should be viewed as a potential therapeutic agent for preventing and/or treating premature skin aging. Terrein is a bioactive fungal metabolite isolated from Penicillium species. Terrein has a relatively simple structure and can be easily synthesized. However, the biologic effects of terrein are comparatively unknown. We found for the first time that terrein potently inhibit melanin production in melanocytes and has a strong hypopigmentary effect in a spontaneously immortalized mouse melanocyte cell line, Mel-Ab. Treatment of Mel-Ab cells with terrein (10-100 mM) for 4 days significantly reduced melanin levels in a dose-dependent manner. In addition, terrein at the same concentration also reduced tyrosinase activity. We then investigated whether terrein influences the extracellular signal-regulated protein kinase (ERK) pathway and the expression of microphthalmia-associated transcription factor (MITF), which is required for tyrosinase expression. Terrein was found to induce sustained ERK activation and MITF down-regulation, and luciferase assays showed that terrein inhibits MITF promoter activity in a dose-dependent manner. To elucidate the correlation between ERK pathway activation and a decreased MITF transcriptional level, PD98059, a specific inhibitor of the ERK pathway, was applied before terrain treatment and found to abrogate the terrein-induced MITF attenuation. Terrein also reduced the tyrosinase protein level for at least 72 h. These results suggest that terrain reduces melanin synthesis by reducing tyrosinase production via ERK activation, and that this is followed by MITF down-regulation.