• Journal of Microbiology and Biotechnology
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• v.25 no.11
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• pp.1954-1959
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• 2015

Bacillus subtilis HM1 was isolated from the rhizosphere region of halophytes for its antifungal activity against Colletotrichum acutatum, the causative agent of anthracnose. Treatment of postharvest apples with the cell culture or with a cell-free culture supernatant reduced disease severity 80.7% and 69.4%, respectively. Both treatments also exhibited antifungal activity against various phytopathogenic fungi in vitro. The antifungal substances were purified and analyzed by acid precipitation, gel filtration, high-performance liquid chromatography, and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Three compounds were identified as fengycin, iturin, and surfactin. The MALDI-TOF/TOF mass spectrum revealed the presence of cyclized fengycin homologs A and B, which were distinguishable on the basis of the presence of either alanine or valine, respectively, at position 6 of the peptide sequence. In addition, the cyclized structure of fengycin was shown to play a critical role in antifungal activity.

• Korean Journal of Environmental Biology
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• v.22 no.4
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• pp.487-493
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• 2004

To investigate the antifungal activity related protein in pesticidal bacteria, a bacterial strain LTD was isolated from soil collected at Gimje in Jeonbuk province, Korea, and identified as Bacillus subtilis LTD based on a API50 CHB kit and 168 rDNA sequencing. It has an antifungal activity against 9 plant pathogenic fungi in a paper disc assay. The antifungal activity- deficient mutant, B. subtilis mLTD was induced at a 5 kGy dose of $^{60}Co$ gamma radiation. Using the two-dimensional electrophoresis and the matrix assisted laser desorption ionization time-of-flight mass spectrometry, the comparison analysis of proteins between the wild and mutant were performed. A major intracellular serine proteinase IspA (MW: 32.5 kDa), a NAD (P) H dehydrogenase (MW: 20.0 kDa), and a stage II sporulation protein AA, SpoIIAA (MW: 14.3kDa) were detected only in the B. subtilis LTD. These results suggested that the functions of these proteins found only in the B. subtilis LTD could. be closely related to the antifungal activity against plant pathogenic fungi.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.5
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• pp.456-463
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• 2011

We attempted to isolate a collagenase-1 inhibitory peptide from skate Dipturus chilensis skin protein. The protein from skate skin was digested by various enzymes (alcalase, ${\alpha}$-chymotrypsin, neutrase, papain, pepsin, and trypsin) to produce a collagenase-1 inhibitory peptide. The collagenase-1 inhibitory activity of the peptides obtained was measured by gelatin digestion assay. Among the six hydrolysates, pepsin hydrolysate exhibited the highest collagenase-1 inhibitory activity. The peptide showing strong collagenase-1 inhibitory activity was purified by Sephadex G-25 gel chromatography and HPLC using an octadecylsilyls (ODS) column. The amino acid sequence of purified collagenase-1 inhibitory peptide was identified to be Asn-Leu-Asp-Val -Leu-Glu-Val-Phe (961 Da) by quadrupole time of flight (Q-TOF) and electrospray ionization mass spectrometry (ESI-MS) mass spectroscopy. The $IC_{50}$ value of purified peptide was 87.0 ${\mu}M$. Moreover, the peptide did not exhibit cytotoxic effects on human dermal fibroblast cell lines.

• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.60-66
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• 2021

Various insects live around us. Nowadays, insects are raised as a hobby at home or medicinal insects are bred in large quantities for commercial purposes. In addition, various studies have been conducted to understand the various growth characteristics of insects. In the laboratory, environmental factors were changed to do that, but only the growth characteristics could be analyzed. However, it is almost not easy to measure the skin temperature or body temperature basically needed to reveal the growth characteristics in the case of insects. In particular, the results of experiments on the skin temperature of winged insects are very insufficient. In this study, the skin temperature of insects was photographed and measured for bees and butterflies living in natural conditions under various biological activity conditions such as at rest and during flight using a thermal imaging camera, a non-contact temperature measurement method. Through quantitative analysis of the experimental results, the relationship between the biological activity characteristics of each insect and the skin temperature resulting from such biological activity was investigated. In addition, it was confirmed that honeybees maintained different skin temperatures for three important activities, such as flying, honey collection, and relocation, and that the butterflies performed a warm-up stage for flight similar to the characteristics of moths.

• Journal of Advanced Navigation Technology
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• v.19 no.5
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• pp.370-378
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• 2015

The data acquisition unit, signal acquiring and processing equipment, processes and provides major data of an aircraft such as engine system, power train system, hydraulic system, etc. However, it had lots of failure related to the system during production test flight, and it is necessary to fix them perfectly as soon as possible because of the significance of the equipment. In this paper, it contains failure classification and analysis for each defect element to improve whole software as well as electrical circuit. Particularly, utilizing Fault Injection Method based interworking test, more efficient improvement activity was performed for not only equipment level but also aircraft level, and as a result, it is achieved that considerable betterment of Surion quality and flight safety.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.507-510
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• 2009

The small size of hybrid rocket using PE-$LN_2O$ was designed, constructed and launched for a development basic technology of Hybrid rocket vehicle. The hybrid engine ignition system was designed with valve system using external actuator and confirmed working without any fault. To design fuel grain an internal ballistics design was carried out, and to estimate rockets flight path an external ballistics analysis was carried out. So the rocket was designed and constructed, and the launch test proves that hybrid rocket's design was suitable. The hybrid rocket(weight : 9kg, diameter : 110 mm, height : 1.7 m) was launched successfully. But parachute was deployed on mid-flight and the mission could not finish its purposed flight. Some of problems were found in this activity but next launch vehicle will be improved.

• Journal of the Ergonomics Society of Korea
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• v.17 no.3
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• pp.13-22
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• 1998

Aircraft and the three-dimensional environment in which they operate are not user-friendly for human beings. As a result, maintaining the proficiencies necessary to safely and efficiently fly an airplane are difficult, and costly. The physiological and emotional status of the human element remains crucial in maintaining safe performance by all crew members. In the study of Hagiwara et al.(1993). they called the physiological and emotional status of the human element into the human alertness or physiological activity and stress, fatigue, circadian rhythm, alcohol. smoking, and self-medication are known the major factors that deteriorate the human alertness. Accordingly. this paper deals with the quantitative and objective performance test based on tracking error and reaction time by means of the new computer test program into which the perception-motion system of human beings is applied. Throughout this experiment using performance test, the results suggest that performance capability in state of sleep deprivation 2 hours and alcoholic 0.05~0.06% in blood were more impaired than one in a normal state, and they further showed statistically significant differences between them, which were influenced by impairment factors of body regulation and pilot's grade. We also obtained the prediction value and the 95% confidence interval of tracking error and reaction time at the normal state for the purpose of distinguishing performance capability between the normal state and the abnormal state. And it is expected that the evaluation of human alertness using performance test will be applied to the quantitative assessment of an each pilot's realistic consciousness/attention, and will lead a flight commander to the accurate decision of mission approval prior to a flight.

• The Journal of the Korea Contents Association
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• v.12 no.7
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• pp.425-436
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• 2012

This research aims to investigate the life-style and types of leisure experienced among airline flight attendants during temporary stays abroad. In this study 2 hypotheses based on literature reviews were employed. Questionnaires were also developed based on data collected from previous studies. Subjects of the study were focused on flight attendants in Legacy Airlines. Factor analysis and reliability coefficients were used to examine the internal consistency among variables. Seven dimensions of leisure, which are cultural experience, pursuit of success, social orientation, humanity, pursuit of fashion, shopping preferences and health-orientation were identified from factor analysis. Three dimensions of leisure, which include type of rest, type of sports, and activity of tourists, were identified from factor analysis accordingly. Lifestyle factors were extracted from a result of cluster analysis, cluster 1- Passive lifestyle, Active lifestyle community type 2, and Cluster 3 analyzed Self-satisfied lifestyle types. Airline cabin crew workers involved in the life style analysis can make good use of leisure time.

• Mycobiology
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• v.43 no.3
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• pp.272-279
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• 2015

To screen molecular chaperones similar to small heat shock proteins (sHsps), but without ${\alpha}$-crystalline domain, heat-stable proteins from Schizosaccharomyces pombe were analyzed by 2-dimensional electrophoresis and matrix assisted laser desorption/ionization time-of-flight mass spectrometry. Sixteen proteins were identified, and four recombinant proteins, including cofilin, NTF2, pyridoxin biosynthesis protein (Snz1) and Wos2 that has an ${\alpha}$-crystalline domain, were purified. Among these proteins, only Snz1 showed the anti-aggregation activity against thermal denaturation of citrate synthase. However, pre-heating of NTF2 and Wos2 at $70^{\circ}C$ for 30 min, efficiently prevented thermal aggregation of citrate synthase. These results indicate that Snz1 and NTF2 possess molecular chaperone activity similar to sHsps, even though there is no ${\alpha}$-crystalline domain in their sequences.

• Journal of Multimedia Information System
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• v.5 no.2
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• pp.121-130
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• 2018

We developed multimedia esophageal catheters for use with birds to measure and record ECG and angular velocity while anesthesized, at rest, and in flight. These catheters enable estimates of blood pressure based on readings given by an angular velocity sensor and by RR intervals of ECG affected by EMG. In our experiments, the catheters had the following characteristics: 1. Esophageal catheters offer a topological advantage with 8-dB SNR improvement due to elimination of electromyography (EMG). 2. We observed a very strong correlation between blood pressure and the angular velocity of esophageal catheter axial rotation. 3. The impulse conduction pathway (Purkinje fibers) of the cardiac ventricle has a direction opposite to that of the mammalian pathway. 4. Sympathetic nerves predominate in flight, and RR interval variations are strongly suppressed. The electrophysiological data obtained by this study provided especially the state of the avian autonomic nervous system activity, so we can suspect individual's health condition. If the change of the RR interval was small, we can perform an isolation or screening from the group that prevent the pandemics of avian influenza. This catheter shall be useful to analysis an avian autonomic system, to perform a screening, and to make a positive policy against the massive infected avian influenza.