• Molecules and Cells
• /
• v.41 no.11
• /
• pp.979-992
• /
• 2018

Potato (Solanum tuberosum L.) is the third most important food crop, and breeding drought-tolerant varieties is vital research goal. However, detailed molecular mechanisms in response to drought stress in potatoes are not well known. In this study, we developed EMS-mutagenized potatoes that showed significant tolerance to drought stress compared to the wild-type (WT) 'Desiree' cultivar. In addition, changes to transcripts as a result of drought stress in WT and drought-tolerant (DR) plants were investigated by de novo assembly using the Illumina platform. One-week-old WT and DR plants were treated with -1.8 Mpa polyethylene glycol-8000, and total RNA was prepared from plants harvested at 0, 6, 12, 24, and 48 h for subsequent RNA sequencing. In total, 61,100 transcripts and 5,118 differentially expressed genes (DEGs) displaying up- or down-regulation were identified in pairwise comparisons of WT and DR plants following drought conditions. Transcriptome profiling showed the number of DEGs with up-regulation and down-regulation at 909, 977, 1181, 1225 and 826 between WT and DR plants at 0, 6, 12, 24, and 48 h, respectively. Results of KEGG enrichment showed that the drought tolerance mechanism of the DR plant can mainly be explained by two aspects, the 'photosynthetic-antenna protein' and 'protein processing of the endoplasmic reticulum'. We also divided eight expression patterns in four pairwise comparisons of DR plants (DR0 vs DR6, DR12, DR24, DR48) under PEG treatment. Our comprehensive transcriptome data will further enhance our understanding of the mechanisms regulating drought tolerance in tetraploid potato cultivars.

• Journal of Korean Academy of Nursing
• /
• v.46 no.6
• /
• pp.804-812
• /
• 2016

Purpose: This research was done to identify the hospital arrival rate and factors related to prehospital delay in arriving at an emergency medical center within the golden time after symptom onset in patients with acute myocardial infarction (AMI). Methods: Data used in the research was from the National Emergency Department Information System of the National Emergency Medical Center which reported that in 2014, 9,611 patients went to emergency medical centers for acute myocardial infarction. Prehospital time is the time from onset to arrival at an emergency medical center and is analyzed by subdividing arrival and delay based on golden time of 2 hour. Results: After onset of acute myocardial infarction, arrival rate to emergency medical centers within the golden time was 44.0%(4,233), and factors related to prehospital delay were gender, age, region of residence, symptoms, path to hospital visit, and method of transportation. Conclusion: Results of this study show that in 2014 more than half of AMI patients arrive at emergency medical centers after the golden time for proper treatment of AMI. In order to reduce prehospital delay, new policy that reflects factors influencing prehospital delay should be developed. Especially, public campaigns and education to provide information on AMI initial symptoms and to enhance utilizing EMS to get to the emergency medical center directly should be implemented for patients and/or caregivers.

• Fire Science and Engineering
• /
• v.28 no.4
• /
• pp.104-111
• /
• 2014

The purpose of this study is to investigate the CPR within ambulance. The Subjects were 890 emergency medical technicians in fire department in Gyeonggido. After continuing education program, the emergency medical technicians completed the questionnaires from January to February, 2012. Questionnaire consisted of demographic characteristics, method of chest compression (one handed or two handed), chest compression - ventilation ratio, and hands only CPR. Data were analyzed by frequency analysis and Chi-square test, t-test. One-way analysis of variance (ANOVA) was followed by Scheffe post-hoc test to analyze changes in all parameters between all groups. One handed chest compression accounted for 14.0% and two handed chest compression accounted for 86.0%. Hands only CPR accounted for 71.7% and standard CPR (30:2) accounted for 28.3%. In order to perform the high quality CPR, as least three persons must be dispatched in the ambulance. The flexible management of manpower may improve the survival from the cardiac arrest. A systemic approach for educating and training EMT's in CPR is needed.

• Microbiology and Biotechnology Letters
• /
• v.36 no.2
• /
• pp.158-164
• /
• 2008

The fusants which contain starch utilizing ability and alcohol fermenting ability were developed by protoplast fusion of Saccharomyces cerevisiae KOY-1 and Saccharomyces diastaticus KCTC 1804. Sacharomyces cerevisiae KH-12 was obtained by haploid induction from Saccharomyces cerevisiae KOY-1. The auxotropic mutants of yeast were obtained by using an ethylmethane sulfonate (EMS). The frequency of protoplast formation in Saccharomyces cerevisiae KOY-1 $(Met^-)$ and Saccharomyces diastaticus KCTC 1804 $(Trp^-)$ were 90.5% and 97.7%, respectively. The frequency of fusant formation was $1.79{\times}10^{-4 }$ for the regenerated protoplast and the 1,000 fusants were obtained. Fusant FA 776 was selected as a potential yeast which contain an alcohol fermenting ability in the starch medium. The genetic stability was 4.64% for 10 passages of generation. Fusant FA 776 produced 13mg/ml of alcohol in 24% starch medium and showed 1.86-fold higher alcohol fermenting ability than Saccharomyces diastaticus KCTC 1804.

• Microbiology and Biotechnology Letters
• /
• v.34 no.2
• /
• pp.136-142
• /
• 2006

Haematococcus pluvialis is a great producer of astaxanthin (3,3'-dihydroxy-$\beta$,$\beta$-carotene-4,4'-dione). The activities of astaxanthin include potential cancer prevention, immune response enhancement, antioxidant activity, and so on. Nevertheless, it tried to manipulate by mutation for overcoming low growth rate of wild type and limited production of astaxanthin. Mutated colony that is lager and more reddish one than wild type was selected by attempting to expose strains to UV irradiation and to treat chemical such as EMS and colchicines as mutagen. Selected mutants were further screened using inhibitors of the carotenoid biosynthetic pathway. Inhibitors used were nicotine and diphenylamine and both had decreased the survival rate by 40-50%. Among over 50,000 mutant colonies screened, two strains were selected. One selected mutant strain (U15-5) from UV treatment showed 1.68-fold higher total carotenoid contents per cell than that of the wild type strain. On the other hand, the other selected mutant strains (DS, M4-3) from colchicine treatment showed 20$\sim$30% faster cell growth than the wild type strain.

• Fire Science and Engineering
• /
• v.34 no.2
• /
• pp.147-155
• /
• 2020

This paper presents a study on the development of a fire extinguishing agent and extinguishing system for an energy storage system (ESS) fire. The fire extinguishing agent designed to extinguish an ESS fire is a highly permeable fire extinguisher that reduces the surface tension and viscosity while bringing about cooling action. This is the main extinguishing effect of this type of wetting agent, which displays the characteristics of fire extinguishing agents used for penetrating the battery cells inside the ESS module. For the fire extinguishing system, a local application system was designed to suppress fire on a rack-by-rack basis. A 360° rotating nozzle was inserted into the rear hall of the ESS module, and general nozzles were installed in the rack to maximize the fire extinguishing effect. The fire extinguishing agent was strongly discharged by virtue of the gas release pressure. Experiments on fire suppression performance with ESS module 1 unit and module 3 units showed that all visible flames were extinguished in 8 s and 9 s, respectively, by the fire extinguishing agent. In addition, based on confirming reignition for 600 s after the fire extinguishing agent was exhausted, it was confirmed that the ESS fire was completely extinguished without reignition in all fire suppression performance experiments.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.17 no.3
• /
• pp.192-202
• /
• 2007

Objectives: The objectives of this research are to examine the missions, organization, and programs of the environmental, health and safety(EHS) offices of the major research universities in the U.S.A., particularly the case of Massachusetts Institute of Technology(MIT) EHS Office, and to suggest ways to address the EHS issues of the universities and research institutes in South Korea. Methods: The top 30 research universities in the U.S.A. were selected by the total amounts of research funds they annually received. The web sites of the 30 universities were searched to identify the names of the departments that address environment, health, and/or safety related issues, the missions of those departments, the major programs of those departments, and the number of staff in those departments. Also, a case study was conducted for the Environment Health and Safety Management System and the Environment, Health and Safety Office of the MIT, using literature and web searches and a meeting with the Director of the MIT Environment, Health and Safety Office. Results: All the top 30 research universities in the U.S.A. had designated departments that dealt with EHS issues. Most of them were by the name of or similar to environmental, health and safety. The mission statements of those departments were mostly about improving the safety and health of their community members, improving the environment, and complying to EHS regulations. Most of those departments had an environmental management program, industrial hygiene program, radiation protection program, safety program, and biosafety program as their major programs. The components of the environment, health and safety management system(EHS-MS) of the MIT were examined in detail. In contrast, not many universities in South Korea had designated departments that dealt specifically with EHS issues. Also, the number of fulltime staff for EHS was only 1-2 in most of the Korean universities and their work duties included only general safety, while neglecting other health/environment related issues. Conclusions: Well organized and functioning environmental, health and safety offices were present in all of the top 30 research universities in the U.S.A., whereas similar organizations of the universities in South Korea were virtually non-existent and/or had very limited EHS activities. Therefore, in order to reduce potential risks of accidents and health problems in the Korean universities and research institutions, well established and functioning EHS-MSs and EHS offices are warranted. The case of the EHS-MS and EHS Office in the MIT demonstrate a successful case to follow.

• KSBB Journal
• /
• v.15 no.2
• /
• pp.113-119
• /
• 2000

In order to produce xylitol with high yield, experiments were carried out to develope xylitol dehydrogenase (XDH) defective m mutant from Pichia stipitis and to investigate the xylit이 fermentation characteristics of mutant strain. After treatment of P s stipitis with EMS, mutant PXM-4 was selected based on the XDH activity and xylitol production capability. Among the tested c cosubstrates, galactose was selected as an adequate cosubstrate on xyl뻐I production of mutant PXM-4. With the increase of galactose concentration, xylitol production was decreased because the transport of xylose into cell was inhibited by g galactose. The optimal concentration of galactose for the production of xylitol using 20 g/L xylose was 20 g/L. Under this c condition, maximum concentration of xylitol and yield were 14.4 g/L and 97%, respectively. In order to prevent the inhibitory e effect of xylose transport by galactose, galactose was fed with low concentration and the concentration of xylitol produced w was increased up to 25 g/L. In the fermentation of corn cob hydrolyzate by mutant PXM-4, xylose was completely converted t to xylit이 with a 100% yield in 4 days culture.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.34 no.3
• /
• pp.129-135
• /
• 2021

Rock sheds are a type of rockfall protection facility that is installed on the road near steep slopes, where large amount of rockfall is expected. Rock sheds are generally designed to resist approximately 200 kJ to 3,000 kJ of rockfall energy. In a previous study, a new type rock shed structure having a concrete-filled tube (CFT) main frame was proposed. By using CFT as the main frame in a rock shed, rapid construction is possible. Additionally, high load carrying capacity and ductility can be achieved. The behavior of the proposed rock shed structure was studied via elastic analysis with the equivalent static load of rockfall energy as in a previous study. However, it is necessary to investigate the behavior of the proposed rock shed in more detail with a full 3D finite element (FE) model considering realistic rockfall load. The FE model for the CFT rock shed main frame was developed first in this study. Then, the resistance of the CFT rock shed main frame Under ultimate rockfall energy was investigated.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.2
• /
• pp.576-582
• /
• 2017

The switching system in a maglev train is an indispensable element for distributing train routes, and it should be designed to ensure safe operation. Unlike conventional wheels on rails, the switching track in EMS-type maglev is supported by a group of 3 to 4 steel girders. When the vehicle changes its route, the segmented track allows the girders to change from a straight position to a curved one with a small radius of curvature. Hence, the structural characteristics of the segmented switching system may affect the levitation stability of the maglev vehicle. This study experimentally evaluates the dynamic interaction between maglev vehicles and a segmented switching system. The results may be helpful for improving the switching system. The measured levitation and lateral air gaps were evaluated at a vehicle speed of 25 km/h, and the ride quality of the Maglev vehicle was determined to be "comfortable" according to the UIC 513 standard.