• Journal of Ginseng Research
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• v.33 no.2
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• pp.104-110
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• 2009

It is well known that the saponin of Korean red ginseng (KRG) has an anti-oxidant effect and could suppress the accumulation of lipid peroxidation. The aim of the present study was to observe the inhibitory effect of KRG on mice with noise-induced hearing loss, and to determine its optimal dose. BALB/c mice with a normal hearing level and normal Preyer's reflexes were used in the study. The mice in the permanent-threshold-shift (PTS) group were exposed to noise (120-dB SPL, white noise band) in a noise booth for 3 h a day, for three consecutive days. The mice in the experimental group were given heat-processed red-ginseng extract (50 mg/kg, 100 mg/kg, and 200 mg/kg), and those in the control group were given normal saline alone during their noise exposure. The mice in the temporary-threshold-shift (TTS) group were exposed to noise (120 dBSPL, white noise band) in a noise booth for 3 h. The mice in the experimental group were given heat-processed red-ginseng extract (50 mg/kg, 100 mg/kg, and 200 mg/kg), and those in the control group were given normal saline alone before their noise exposure. The hearing levels of the mice were measured through auditory brainstem response (ABR) immediately and I, 3, 5, 7, and 14 days after their noise exposure. Cochleae were removed from the mice 14 days after their noise exposure. lmmunochemical and immunofluorescent staining were performed to observe the expression of 8-oxoG in cochlea. In the PTS group, the hearing function of the mice in all the groups was not recovered after their noise exposure. In the TTS group, however, the hearing function of the mice in all the groups was recovered within 14 days. Reduced hearing impairment and early recovery were observed in the mice that were given 200 mg/kg KRG, and early recovery was observed in the mice that were given 100 mg/kg KRG The immunopositive staining of 8-oxoG was detected in the stria vascularis in the control group but was diminished in the mice that were given 200 mg/kg KRG The ingestion of more than 100 mg/kg KRG demonstrated a protection and recovery effect on the noiseinduced-TTS group. Since KRG has been reported to be a safe compound even up to hundreds of mg/kg, a higher concentration of it may effectively protect and recover TTS.

• Journal of Chest Surgery
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• v.30 no.10
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• pp.949-960
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• 1997

Background. Limited ischemic tolerance of the lung has remained one of the factors that limits the expansion of pulmonary transplantation as a treatment for end-stage pulmonary disease. Numerous studies on safe long term preservation for lung transplantation has been performed for the purpose of developing ideal preservation solution with extracellular type or intracellular type solutions. In this. study, we examined the efficacy of L DG solution in lung preservation longer than 20 hours by comparison with modified Euro-Collins solution. Iwethods. Thirty-(our adult mongrel dogs were divided into two groups. Donor lungs were flushed with LPDG solution(n=9) or modified Euro-Collins(MEC) solution(n=8) and stored for 24 hours at 1$0^{\circ}C$. All donor lungs were perfused through the pulmonary arteries with solutions containing prostaglandin El and verapamil. Left canine lung allotransplantations wereperformed. Assessment(hemodynamic indices and arterial blood gas analysis) of left implanted lung was made by occluding the right pulmonary artery for ten minutes using pulmonary artery Cuff. Assessment was repeated at the interval of 30 minutes, one hour, and two hours later after reperfusion and then chest X-ray, computed tomogram and lung perfusion scan were obtained. In survival dogs follow-up studies were done with assessment with chest X-ray, computed tomogram of the chest and lung perfusion scan on 7th day postoperatively. After preservation above 20 hours, pathological examinations for ultrastructural findings on right lung were performed in each group. Results. With respect to arterial oxygen tension, LPDG group was superior to MEC but there was no statistical significance for 2 hours after reperfusion. Mean pulmonary artery pressure was less increased(p < 0.05) and cardiac output higher(p <0.05) than MEC group until 2 hours after reperfusion. After 2 hours of reperfusion, both groups showed transplanted lung function deteriorated gradually. Perfusion scan of the transplanted lung in LPDG group showed better perfusion rate in immediate post-reperfusion, 3 days and 7 days later respectively but there was no statistical significance and corelation with PaO2 and computed tomoRravhic views. In scanning electron microscopy of pulmonary artery after preservation, LPDG group relatively shows less irregular protrusion of the inner surface of endothelial cell of poulmonary artery than MEC group. Conclusions, e concluded that LPDG solution can offer safe lung preservation above 20 hours with adequate immunosuppressive therapy and prevention of the infection.

• Journal of Dental Rehabilitation and Applied Science
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• v.24 no.3
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• pp.269-281
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• 2008

Fatigue or overload can result in mechanical problems of implant components. The mechanical strength in the implant system is dependent on several factors, such as screw and fixture diameters, material, and design of the fixture-abutment connection and abutment. In these factors, the last rules the strength and stability of the fixture-abutment assembly. There have been some previous reports on the mechanical strength of the fixture-abutment assembly with the compressive bending test or short-term cyclic loading test. However, it is restrictive to predict the long-term stability of the implant system with them. The purpose of this study was to evaluate the influence of the design of the fixture-abutment connection and abutment on the mechanical strength and failure mode by conducting the endurance limit test as well as the compressive bending strength test. Tests were performed according to a specified test(ISO/FDIS 14801) in 4 fixture-abutment assemblies of the Osstem implant system: an external butt joint with Cemented abutment (group BJT), an external butt joint with Safe abutment (group BJS), an internal conical joint with Solid abutment (group CJO), and an internal conical joint with ComOcta abutment (group CJT). The following conclusions were drawn within the limitation of this study. Compressive bending strengths were decreased in order of group BJS(1392.0N), group CJO(1261.8N), group BJT(1153.2N), and group CJT(1110.2N). There were no significant differences in compressive bending strengths between group BJT and group CJT(P>.05). Endurance limits were decreased in order of group CJO(600N), group CJT(453N), group BJS(360N), and group BJT(300N). 3. Compressive bending strengths were influenced by the connection and abutment design of the implant system, however endurance limits were affected more considerably by the connection design.

• Journal of Chest Surgery
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• v.30 no.8
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• pp.752-759
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• 1997

Profound hypothermia protects . cerebral function during total circulatory arrest(TCA) in the surgical treatment of a variety of cardiac and aortic diseases. Despite its importance, there is no ideal technique to monitor the brain injury from ischemia. Since 1994, we have developed compressed spectral array(CSA) of electroencephalography(EEG) and monitored cerebral activity to reduce ischemic injury. The purposes of this study are to analyse the efficacy of CSA and to establish objective criteria to consistently identify the safe level of temperature and arrest time. We studied 6 patients with aortic dissection(AD, n=3) or aortic arch aneurysm(n=3, ruptured in 2). Body temperatures from rectum and esophagus and the EEG were monitored continuously during cooling and rewarming period. TCA with cerebral ischemia was performed in 3 patients and TCA with selective cerebral perfusion was performed in 3 patients. Total ischemic time was 30, 36 and 56 minutes respectively for TCA group and selective perfusion time was 41, 56 and 92 minutes respectively for selective perfusion group. The rectal temperatures for flat EEG were between 16.1 and 22. $1^{\circ}C$ (mean: 18.4 $\pm$ 2.0): the esophageal temperatures between 12.7 and $16.4^{\circ}C$ (mean $14.7\pm1.6).$ The temperatures at which EEG reappeared $5~15.4^{\circ}C$ for esophagus. There was no neurological defic t and no surgical mortality in this series. In summary, the electrical cerebral activity Teappeared within 23 minutes at the temperature less than $16^{\circ}C$ for rectum. It seemed that $15^{\circ}C$ of esophageal temperature was not safe for 20 minutes of TCA and continuous monitoring the EEG with CSA to identify the electrocerebral silence was useful.

• Food Science and Preservation
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• v.19 no.5
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• pp.633-638
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• 2012

The aim of this study was to investigate the growth of aerobic bacteria in fresh-cut salad during short-term temperature abuse ($4{\sim}30^{\circ}C$temperature for 1, 2, and 3 h) for 72 h and to develop predictive models for the growth of total viable cells (TVC) based on Predictive food microbiology (PFM). The tool that was used, Pathogen Modeling program (PMP 7.0), predicts the growth of Aeromonas hydrophila (broth Culture, aerobic) at pH 5.6, NaCl 2.5%, and sodium nitrite 150 ppm for 72 h. Linear models through linear regression analysis; DMFit program were created based on the results obtained at 5, 10, 20, and $30^{\circ}C$ for 72 h ($r^2$ >0.9). Secondary models for the growth rate and lag time, as a function of storage temperature, were developed using the polynomial model. The initial contamination level of fresh-cut salad was 5.6 log CFU/mL of TVC during 72 h storage, and the growth rate of TVC was shown to be 0.020~1.083 CFU/mL/h ($r^2$ >0.9). Also, the growth tendency of TVC was similar to that of PMP (grow rate: 0.017~0.235 CFU/mL/h; $r^2=0.994{\sim}1.000$). The predicted shelf life with PMP was 24.1~626.5 h, and the estimated shelf life of the fresh-cut salads with short-term temperature abuse was 15.6~31.1 h. The predicted shelf life was more than two times the observed one. This result indicates a 'fail safe' model. It can be taken to a ludicrous extreme by adopting a model that always predicts that a pathogenic microorganism will grow even under conditions so strict as to be actually impossible.

• The Journal of Internal Korean Medicine
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• v.29 no.4
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• pp.1000-1010
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• 2008

Objective : Hypothyroidism is a syndrome characterized by symptoms such as cold intolerance, or weight gain. Because of side effects of Western medicine treatment, interest in oriental medicine has been increasing. In this study, we examined the therapeutic effects of Evodiae fructus and histological modification in hypothyroidism rat model induced by PTU(6-propyl, 2-thiouracil). Methods : After inducing hypothyroidism in the rats by PTU injections, we divided the rats into four groups, the Evodiae fructus 100 500, control, and $LT_4$ (levothyroxine) groups. After 2 weeks Evodiae fructus and $LT_4$ were administered, respectively. The weight was measured once a week. After sampling the blood for biochemical analysis to check the levels of $T_3$, $T_4$ and TSH, the thyroid tissue was removed, stained with H&E, and an image was obtained using an optical microscope. Results : Compared with normals, controls showed low $T_4$ and high TSH. The Evodiae fructus group showed a statistically meaningful $T_3$ increase to be dose related. But the levels of TSH showed no meaningful difference between the Evodiae fructus group and normals. About the biochemical tests(liver, kidney etc) and weight change, there was no meaningful difference between the Evodiae fructus group and controls. In the biopsy, the Evodiae fructus group showed thyroid tissue improvement compared to controls. Conclusions : These results show that Evodiae fructus stimulates the decreased functions of the thyroid, and also has thyroid cell protecting effects. The lab results also showed that Evodiae fructus is a safe substance that doesn't cause hepatotoxicity or nephrotoxicity. Therefore it is an effective substance in the treatment of hypothyroidism.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.8 no.2
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• pp.49-59
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• 2002

The main function of plastic materials in food packaging is to preserve a food for safe transportation and storage. The interactions between food and plastic materials in food packaging have become increasingly important for food quality and safety because monomer, low molecular weight components, or additives of plastic packaging materials can migrate into a food. The use of antioxidants in plastic materials can help protect the degradation of film itself and retard the oxidation of a packaged food containing lipid, through the migration of antioxidant from the packaging to a product via an evaporation / sorption mechanism. Nowadays, antioxidant (BHT) impregnated plastic materials are used for commercial food packaging application with the intention of achieving an extended shelf life of food in USA. Alpha tocopherol, as one of the most important free radical scavengers, has been well known in biological systems. Moreover, the potential use of alpha tocopherol as an additive for polymers used in the packaging industry may offer the most positive perception from both consumers and manufacturers. Alpha tocopherol has been used as an antioxidant for polyolefin resins fabricated to both bottles and film and has applications in the food packaging industry as a replacement for BHT. Today, alpha tocopherol offers an attractive choice for use as an antioxidant in polymers. This paper provides an overview of antioxidant effectiveness and applications for its use by the food packaging industry based on the evaporation-sorption mechanism of a packaging model product, where quality is associated with lipid oxidation. Important analytical techniques for predicting antioxidant interaction between the package system and product are discussed.

• Journal of the Korean Society for Marine Environment & Energy
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• v.20 no.2
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• pp.107-116
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• 2017

When drilling operation is being performed, many physical and chemical changes are occurred near wellbore. To handle various changes of well condition and keep drilling process safe, additives of bulk, such as bentonite for increasing density of drilling mud, barite for increasing viscosity of drilling mud, polymer for chemical control, or surfactant, are added into drilling mud through a mud shear mixer. Because the achievement of the required material property through mud mixing system is essential to stabilize drilling system, it is of importance to analyze multi-phase flow during mud mixing process, which is directly related to increase mixing performance of the system and guarantee the safety of the whole drilling system. In this study, a series of liquid-solid flow simulation based on a computational fluid dynamics (CFD) are performed with comparing to solid concentration in experiment by Gilles et al. [2004] to understand the characteristics of liquid-solid mixing in a mud shear mixer. And then, the simulation-based design of shear mixer are carried out to improve mixing performance in a mud handling system.

• The Journal of the Korea Contents Association
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• v.9 no.12
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• pp.385-390
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• 2009

The Pneumatic Reduction and VCUG (Voiding Cystourethrography) are commonly used in the paediatric age group. The procedures had a particularly long fluroscopic screening time, despite a successful outcome for paediatric patients. Pneumatic Reduction and VCUG almost invariably requires fluoroscopic guidance which does confer a radiation dose. This article contains suggestions on how the radiation dose to paediatric patients from Pneumatic Reduction and VCUG can be made "as low as reasonably achievable" (ALARA). The aim of our study was eliminated in spot image applying the FluoroGrab, which has function of capturing an image of interest area from the picturing while fluoroscopic procedures. FluoroGrab has clinical value equivalent to the spot image, and is applied to the most recent fluoroscopic procedures. The radiologist and the radiographers should consider new option for decreasing the radiation exposure delivered to paediatric patients by making equipment modifications to the fluoroscopy to optimize radiation exposure reduction techniques. Thus, we propose the FluoroGrab instead of spot exposure for the reduction of patient exposure dose in paediatric, and try to confirm the effect of the mitigating amount of radiation exposure to paediatric patients when pneumatic reduction and VCUG. Fluorograb is the safe and useful method that shows the equivalent level of accuracy to spot exposure, and to minimize the radiation load to paediatric patients are to be the substitute for the spot exposure for Pneumatic Reduction and VCUG.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.5
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• pp.465-475
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• 2020

I-D-F curves were induced by Box-Cox transformation using rainfall data from five major cities in Korea: Seoul, Busan, Daegu, Daejeon, and Gwangju, as well as from Sancheong (South Gyeongsang province) and Yeongcheon (North Gyeongsang province) stations. The practicality of the Box-Cox transformation is more scalable than the traditional method of frequency analysis in terms of applicability because it is available even if the analysis data are insufficient to perform general frequency analysis and do not produce an appropriate probability density function. For the case in which rainfall data for the entire period (10-1440 minutes) and short-term period (20, 30, 40, 50 minutes) at the foregoing 7 stations are omitted, there was a relative error of -23.0 % to 14.7 % at a duration of 10 to 60 minutes below the 100-year frequency. Accordingly, rainfall analysis requires inducing I-D-F curves, including for the short term (20, 30, 40, 50 minutes), and if rainfall data are omitted for the short term (20, 30, 40, 50 minutes), it is necessary to increase the existing margin rate depending on the point in order to ensure the safe design of small-scale hydraulic structures.