• Journal of Chest Surgery
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• v.31 no.9
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• pp.884-892
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• 1998

Background: The gastroepiploic artery is not only an alternative graft but also may be considered an important primary graft for coronary revascularization. However, the long-term patency of the gastroepiploic arterial graft is yet to be determined and the incidence of perioperative spasm and long-term patency of a coronary graft may be affected by the properties of the graft response to certain vasoactive substances. The reactivity of the gastroepiploic artery to vasoactive substances has not been studied extensively and the results of the studies are contradictory. Material and Method: This study was designed to test the reactivity of human gastroepiploic artery to four constrictors and four relaxants. The middle sections of the human gastroepiploic arteries were collected from the patients undergoing gastrectomy and the arterial rings with intact endothelium were suspended in organ baths for isometric tension recording. Result: Epinephrine, norepinephrine, and potassium chloride induced the maximum constriction to higher forces (7.0$\pm$1.1g, 6.6$\pm$0.9g, and 6.5$\pm$1.1g) than 5-hydroxytryptamine did (3.8$\pm$1.7g, p<0.05). Nitroprusside and histamine induced almost full relaxation in the gastroepiploic arteries preconstricted with norepinephrine. There was no significant difference between two relaxants regarding maximum relaxation force. Acetylcholine induced the maximum relaxation to weaker force when compared with nitroprusside and histamine (p<0.05), and isoproterenol was the weakest of the relaxants (p<0.05 compared with acetylcholine). Conclusion: The gastroepiploic artery has a strong capacity of endothelium-dependent relaxation which could have an important influence on long-term patency. The gastroepiploic artery exhibits a potent contractility to catecholamines and the enhanced contractility may facilitate vasospasm in the presence of high circulating levels of catecholamines. Nitroprusside, a potent relaxant in gastroepiploic artery, might be beneficial for the treatment of gastroepiploic arterial graft spasm. The gastroepiploic arterial graft with intact endothelium may respond weakly to beta-adrenoceptor agonist and 5-hydroxytryptamine.

• Journal of Chest Surgery
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• v.42 no.6
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• pp.732-737
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• 2009

Background: Many video-assisted thoracic surgery (VATS) lobectomies are performed as a potential alternative to thoracotomy despite the controversy about the safety and the associated morbidity/mortality rates. Material and Method: Between November 2006 and August 2008, we performed 87 lobectomies (VATS 36, Thoracotomy 51) and we retrospectively reviewed the surgical treatment results. A VATS lobectomy was performed by a 4~5 cm thoracotomy without rib spreading and this included anatomic hilar dissection, individual vessel and bronchus stapling and lymph node dissection. Result: We studied 52 male and 35 female patients whose age ranged from 6 to 79 (average age: $59.8{\pm}15.0$ years). The cases were diagnosed with lung cancer (66) (SQC 24, ADC 38, others 4), pulmonary metastasis (2), carcinoid (2) and benign diseases (17). There was no intraoperative death. Postoperative complications were seen in 5 (15.6%) VATS and 33 (64.7%) thoracotomies, and perioperative death caused by adult respiratory distress syndrome occurred in 1 (2.8%) VATS and 3 (5.9%) thoracotomies. Three patients Underwent conversion to thoracotomy (8.3%). The mean time to chest tube removal was 6 days for VATS and 9.4 days for thoracotomy (p<0.001), and the mean length of the hospital stay was 8 days for VATS and 12.8 days for thoracotomy (p<0.001). Conclusion: VATS lobectomy can be performed safely with low morbidity/mortality rates. Furthermore, all the patients benefited from earlier postoperative rehabilitation and less pain and they were candidates for an earlier return to normal activities.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.962-973
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• 2017

Concerns about an air pollution are gradually increasing at home and abroad. The automotive and fuel researchers are trying to reduce emissions and greenhouse gases of vehicles through a research on new engine designs and innovative after-treatment systems using clean fuels (eco-alternative fuel) and fuel quality improvements. In this paper, we stduy the emission characteristics of greenhouse gases on seven vehicles using gasoline, diesel, and LPG by legal test mode in domestic and abroad.(Urban mode, Highway mode, rapidly acceleration and deceleration, using air conditioner, low temperature condition) Regardless of fuels, most of the greenhouse gases tend to show the worst results in cold FTP-75 mode. In the case of A vehicles (2.0 MPI) and B vehicles (2.4 GDI) using a gasoline fuel, the factors that increase greenhouse gases are in order of a rapidly acceleration and deceleration, using air conditioner, low temperature condition. But G vehicles(LPLi) have different emission characteristics from another vehicles. In the case of A vehicles (2.0 w/o DPF) and B vehicles (2.2 with DPF) using a diesel fuel, the factors that increase greenhouse gases are in order of a rapidly acceleration and deceleration, using air conditioner, low temperature condition. However, the factor of F vehicles are in order of low temperature condition, using air conditioner, rapidly acceleration and deceleration. In conclusion, it will be an effective method to apply different technologies of emission reduction for each fuel.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.874-882
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• 2017

As the interest on the air-pollution is gradually rising up at home and abroad, automotiv e and fuel researchers have been working on the exhaust emission reduction from vehicles through a lot of approaches, which consist of new engine design, innovative after-treatment systems, using clean (eco-friendly alternative) fuels and fuel quality improvement. This research has brought forward three main issues : evaporative, performance, air pollution. In addition, researcher studied the environment problems of the bio-ethanol, bio-butanol, bio-ETBE (Ethyl Tertiary Butyl Ether), MTBE (Methyl Tert iary Butyl Ether) fuel contained in the fuel as octane number improver. The researchers have many dat a about the health effects of ingestion of octane number improver. However, the data support the con clusion that octane number improver is a potential human carcinogen at high doses. Based on the bio-fuel and octane number improver types (bio-ethanol, bio-butanol, bio-ETBE, MTBE), this paper dis cussed the influence of gasoline fuel properties on the evaporative emission characteristics. Also, this p aper assessed the acceleration and power performance of gasoline vehicle for the bio-fuel property. As a result of the experiment, it was found that all the test fuels meet the domestic exhaust gas standards, and as a result of measurement of the vapor pressure of the test fuels, the bio - ethanol : 15 kPa and the biobutanol : 1.6 kPa. thus when manufacturing E3 fuel, Increasing the biobutanol content reduces evaporation gas and vapor pressure. In addition, Similar accelerating and powering performance was shown for the type of biofuel and when bio-butanol and bio-ethanol were compared accelerated perf ormance was improved by about 3.9% and vehicle power by 0.8%.

• Journal of Yeungnam Medical Science
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• v.12 no.2
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• pp.366-385
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• 1995

Epidemiological studies are important in both the prevention and treatment of mycobacterial infections. This study was initiated to establish the pulsed-field gel electrophoresis (PFGE) method, which are not yet extensively studied. The most apprpriate restriction endonucleases included DraI, AsnI, and XbaI. The optimal PFGE condition was different according to the enzymes used. Two stage PFGE was performed, in case of DraI first stage was performed with 10 seconds of initial pulse and 15 seconds of final pulse, while the second stage was performed with 60 seconds of initial pulse and 70 seconds of final pulse. The electrophoresis time for DraI-PFGE was 14 hours for each stage. Electrophoresis was performed for 22 hours, in case of XbaI, with 3 seconds of initial pulse and 12 seconds of final pulse. Electrophoresis was performed for 22 hours, in case of AsnI, with 5 seconds of initial pulse and 25 seconds of final pulse. In all cases the voltage of the electrophoresis was maintained constantly at 200 voltage. Standard mycobacterial strains, which included Mycobacterium bovis BCG, M. tuberculosis, and M. fortuitum, could not be differentiated by PFGE analysis. PFGE analysis was performed to differentiate 9 clinically isolated M. fortuitum strains using AsnI. All M. fortuitum strains showed different genotypes except 2 strains. Cluster analysis divided M. fortuitum strains into 2 large groups. PFGE analysis was performed to further differentiate M. fortuitum isolates using XbaI. The undifferentiated 2 M. fortuitum strains showed different PFGE patterns with Xba I. Cluster analysis of the XbaI-PFGE patterns showed more complex grouping than AsnI-PFGE patterns, which showed that XbaI-PFGE analysis was better than AsnI-PFGE in M. fortuitum genotyping. The top dissimilarity values of AsnI-PFGE and XbaI-PFGE were 0.74 and 0.75, respectively. This value was higher than that of arbitrarily primed polymerase chain reaction (AP-PCR) analysis and lower than that of restriction fragment length polymorphism (RFLP) analysis. This suggested that PFGE can be used as a supportive or alternative genotyping method to RFLP analysis.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1108-1119
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• 2018

As the interest on the air pollution is gradually rising at home and abroad, automotive and fuel researchers have been studied on the exhaust and greenhouse gas emission reduction from vehicles through a lot of approaches, which consist of new engine design, innovative after-treatment systems, using clean (eco-friendly alternative) fuels and fuel quality improvement. This research has brought forward two main issues : exhaust emissions (regulated and non-regulated emissions, PM particle matter) and greenhouse gases of vehicle. Exhaust emissions and greenhouse gases of automotive had many problem such as the cause of ambient pollution, health effects. In order to reduce these emissions, many countries are regulating new exhaust gas test modes. Worldwide harmonized light-duty vehicle test procedure (WLTP) for emission certification has been developed in WP.29 forum in UNECE since 2007. This test procedure was applied to domestic light duty diesel vehicles at the same time as Europe. The air pollutant emissions from light-duty vehicles are regulated by the weight per distance, which the driving cycles can affect the results. Exhaust emissions of vehicle varies substantially based on climate conditions, and driving habits. Extreme outside temperatures tend to increasing the emissions, because more fuel must be used to heat or cool the cabin. Also, high driving speeds increases the emissions because of the energy required to overcome increased drag. Compared with gradual vehicle acceleration, rapid vehicle acceleration increases the emissions. Additional devices (air-conditioner and heater) and road inclines also increases the emissions. In this study, three light-duty vehicles were tested with WLTP, NEDC, and FTP-75, which are used to regulate the emissions of light-duty vehicles, and how much emissions can be affected by different driving cycles. The emissions gas have not shown statistically meaningful difference. The maximum emission gas have been found in low speed phase of WLTP which is mainly caused by cooled engine conditions. The amount of emission gas in cooled engine condition is much different as test vehicles. It means different technical solution requires in this aspect to cope with WLTP driving cycle.

• Economic and Environmental Geology
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• v.52 no.1
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• pp.1-12
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• 2019

Batch experiments for the soil washing coupled with the magnetic separation process were performed to remediate the soil contaminated with metal and oil wastes. The soil was seriously contaminated by Zn and TPH (total petroleum hydrocarbon), of which concentrations were 1743.3 mg/kg and 3558.9 mg/kg, respectively, and initial concentrations of Zn, Pb, Cu, and TPH were higher than the 2nd SPWL (soil pollution warning limit: remediation goal). The soil washing with acidic solution was performed to remove heavy metals from the soil, but Pb and Zn concentration of the soil maintained higher than the 2nd SWPL even after the soil washing with acidic solution. The 2nd soil washing was repeated to increase the Pb and Zn removal efficiency and the Zn and Pb removal efficiencies additionally increased by only 8 % and 5 %, respectively, by the 2nd soil washing (> 2nd SPWL). The small particle separation from the soil was conducted to decrease the initial concentration of heavy metals and to increase the washing effectiveness before the soil washing and 4.1 % of the soil were separated as small particles (< 0.075 mm in diameter). The small particle separation lowered down Zn and Pb concentrations of soil to 1256.3 mg/kg (27.9 % decrease) and 325.8 mg/kg (56.3 % decrease). However, the Zn concentration of soil without small particles still was higher than the 2nd SPWL even after the soil washing, suggesting that the additional process is necessary to lower Zn concentration to below the 2nd SPWL after the treatment process. As an alternative process, the magnetic separation process was performed for the soil and 16.4 % of soil mass were removed, because the soil contamination was originated from unreasonable dumping of metal wastes. The Zn and Pb concentrations of soil were lowered down to 637.2 mg/kg (63.4 % decrease) and 139.6 mg/kg (81.5 % decrease) by the magnetic separation, which were much higher than the removal efficiency of the soil washing and the particle separation. The 1st soil washing after the magnetic separation lowered concentration of both TPH and heavy metals to below 2nd SPWL, suggesting that the soil washing conjugated with the magnetic separation can be applied for the heavy metal and TPH contaminated soil including high content of metal wastes.

• Journal of the Society of Disaster Information
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• v.17 no.1
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• pp.10-24
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• 2021

Purpose: The purpose of this study is to determine the dangers of biodiesel and general diesel mixtures currently used as alternative fuels by equipment (tag method and penski Marten method) and to determine the difference between flash point and combustion point (closed, open) according to test methods. It is intended to be used as a reference material for identification and evaluation of firecausing substances by confirming the risk of mixtures by comparative analysis and measurement, and establishing a risk assessment method for chemical substances. Method: Flash point test method and result treatment were tested based on ASTM and KS M mode, which are tag sealing and pen schematense test methods used as flash point and combustion point test methods for crude oil and petroleum products. The manufacturer of the equipment used in this experiment was a test equipment that satisfies the test standards of KS M 2010 with equipment produced by TANAKA of Japan. The flash point and combustion point were measured, and the flash point according to the test method of biodiesel and general diesel mixture ( Closed, open), and the ignition point of a mixture of biodiesel and general diesel was compared and analyzed for ignition risk compared with conventional diesel. Results: Looking at the experimental results, first, as an analysis of the risk of flammability of the mixture, the flash point of a substance containing 70% biodiesel was found to be about 92℃ based on general diesel with a flash point of 64.5℃, and gasoline and biodiesel or When the biodiesel mixture was synthesized, it was confirmed that the flash point tends to decrease. In addition, the difference between the flash point and the combustion point was analyzed as about 20 ~ 30℃, and when a small amount of gasoline or methanol was mixed, the flash point was lowered, but it was confirmed that the combustion point was similar to that of the existing mixture. Conclusion: In this study, in order to secure the effectiveness of the details of the criteria for judging dangerous materials in the existing Dangerous Materials Safety Management Act, and to secure the reliability and reproducibility of the judgment of dangerous materials, we confirm the criteria for judging the risk of the mixture through an experimental study on flammable mixtures. It will be able to provide reference data for experimental criteria for flammable liquids that are regulated in the field. In addition, if this study accumulates know-how on experiment by test method, it is expected that it can be used as a basis for research on risk assessment and research on dangerous goods.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.46 no.4
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• pp.319-327
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• 2020

Particulate matters (PM) are small particulate pollution that decrease the function of skin barrier, which causes inflammatory skin diseases and extrinsic aging. In this study, we evaluated the effect of preventing the adherence of PMs from several cosmetic products applied to human skin using iron oxide black. The PM floating chamber consists of skin exposure area, PM inlet, floating power device, and an outlet so that PM can be naturally attached to the skin while floating in the chamber. The change in skin brightness according to the floating concentration of alternative fine dust was checked to confirm the optimal floating concentration conditions. The intensity difference (before-after intensity, Δ) before and after adhesion of iron oxide black was proportional to the amount of PM adhered. The anti-adherence effect of iron oxide black on five cosmetic products were evaluated through 20 each subjects by comparing the amount of iron oxide black adhered on the control and treatment. The difference in brightness before and after the iron oxide black attached to the skin was calculated and compared with the control group(p < 0.05). When over 150 mg of iron oxide black was adhered on the skin, the interference of intensity was low and clearly showed the skin adhered pattern. According to the application of the five cosmetics, the intensity difference was significantly lower than the control group. This means that depending on the product, it prevented the attachment of iron oxide black. This study is a safe and useful method to confirm the prevention of PM skin adherence. In conclusion, cosmetics can prevent the adherence of PM on the skin according to the formulation or ingredients characteristics.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.2
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• pp.275-285
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• 2021

COVID-19 is threatening the safety of ships and seafarers by delaying seafarer rotation. Shipping companies and governments have a blindspot in case of the onboard environment of seafarers. An effective, alternative plan should be devised to eliminate the possibility of human accidents in an emergency that threatens the safety of seafarers. According to the survey of former and current seafarers, the most important factor in boarding life was safety, and the most necessary thing during emergencies was to secure smooth seafarer rotation rather than improve wages and welfare. By analyzing the major routes of national shipping companies by continent, ports with a large number of calls and a high Air Connectivity Index were selected as the base port. In addition, the route was designed for effective, domestic seafarer rotation during international shipping. Other countries must be consulted to establish a travel route linking ships, ports, and airports for the safe return of sailors to their home countries during an emergency. In addition, it is necessary to work together for the seafarers who are in trouble of seafarer rotation through cooperation with the International Maritime Organization(IMO). Starting with this, the government should have a monitoring system for the return and non-return routes as well as the number of seafarers on board. If such a system is established, it will be able to determine the response direction of our country's policy in case of an emergency. Along with the shipping company's ef orts to improve the treatment of seafarers, national and social attention will be needed to review domestic laws and improve awareness about seafarers.