• Korean Journal of Plant Tissue Culture
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• v.27 no.5
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• pp.411-413
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• 2000

The ability of microspores or young pollen grains (male gametophytes) to undergo developmetal switch to embryogenic (sporophytic) pathway exemplifies the concept of totipotency as applied to haploid posmeiotic cells. As a first step pollen is devoid of positional information provided in situ by the intact anther - by isolation and cultivation in vitro in artificial media. This is inevitably accompanied by some degree of stress response in microspore/pollen. It has been shown in both monocots and dicots that intentional stress treatment (mostly starvation or heat shock) greatly stimulates embryo induction rate. Using transgenic sHSP antisense Nicotiana tabacum we show that expression of small heat shock proteins is an integral part of successful embryo and later haploid plant production from pollen grains. Our recently published data show that sHSP chaperone function is optimal in the absence of ATP.

• Development and Reproduction
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• v.19 no.2
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• pp.61-67
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• 2015

The immediate early gene c-fos has long been known as a molecular marker of neural activity. The neuron's activity is transformed into intracellular calcium influx through NMDA receptors and L-type voltage sensitive calcium channels. For the transcription of c-fos, neural activity should be strong enough to activate mitogen-activated protein kinase (MAPK) signaling pathway which shows low calcium sensitivity. Upon translation, the auto-inhibition by Fos protein regulates basal Fos expression. The pattern of external stimuli and the valence of the stimulus to the animal change Fos signal, thus the signal reflects learning and memory aspects. Understanding the features of multiple components regulating Fos signaling is necessary for the optimal generation and interpretation of Fos signal.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3691-3695
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• 2012

Photocatalytic reduction of hexavalent chromium (Cr(VI)) in ferric-tartrate system under irradiation of visible light was investigated. Effects of light resources, initial pH value and initial concentration of various reactants on Cr(VI) photocatalytic reduction were studied. Photoreaction kinetics was discussed and a possible photochemical pathway was proposed. The results indicate that Fe(III)-tartrate system is able to rapidly and effectively photocatalytically reduce Cr(VI) utilizing visible light. Initial pH variations resulte in the concentration changes of Fe(III)-tartrate complex in this system, and pH at 3.0 is optimal for Cr(VI) photocatalytic reduction. Efficiency of Cr(VI) photocatalytic reduction increases with increasing initial concentrations of Cr(VI), Fe(III) and tartrate. Kinetics analysis indicates that initial Fe(III) concentration affects Cr(VI) photoreduction most significantly.

• Korean Journal of Construction Engineering and Management
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• v.11 no.6
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• pp.14-23
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• 2010

A considerable number of construction disasters occurs on pathway. A safety management in construction sites is usually performed to prevent accidents in activity areas. This means that safety management level of hazards on pathway is relatively minified. Many researchers have introduced that a hazard identification is fundamental of safety management. Thus, algorithms for helping safety managers' hazardous area identification is developed using automated data collection technology. These algorithms primarily search potential hazardous area by comparing workers' location logs based on real-time locating system and optimal routes based on BIM. And potential hazardous areas is filtered by identified hazardous areas and activity areas. After that, safety managers are provided with information about potential hazardous areas and can establish proper safety countermeasures. This can help improving safety in construction sites.

• Asian Oncology Nursing
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• v.12 no.3
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• pp.204-212
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• 2012

Purpose: To investigate the effectiveness and variance of a critical pathway (CP) for laparoscopic colon resection in colon cancer patients, and nurses'satisfaction with the CP. Methods: A CP for laparoscopic colon resection was applied to the CP-group that included 50 patients, who underwent elective colon resection between March and May, 2011. The non-CP group included 51 patients who had the same operation without the CP applied from March to May, 2010. Results: The means of length of hospital stay were 11.7 and 7.3 days (p<.001) and the lengths of postoperative hospital stay were 8.6 and 5.1 days (p<.001) in the non-CP group and CP group, respectively. There was no significant difference between two groups for total healthcare costs, pain score, complications, or emergency room visits within 30 days after discharge. By examining variances of the CP, there were 162 variances and the most frequent cause was patient's condition. Nurses'satisfaction with the use of CP was favorable and the mean score of satisfaction was 3.76 on the 5 point Likert scale. Conclusion: There are clear benefits to use of CP, resulting in standardized and effective patient care. In conclusion, analysis of variance data can assist in evaluating and revising CP for optimal care and reducing variances.

• Korean Journal of Microbiology
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• v.27 no.1
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• pp.63-69
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• 1989

A pink-pigmented facultative methylotrophic bacterium, Methylobacterium sp. strain SY1, was isolated from soil through methanol-enrichment culture technique. The isolate was gram-negative, slightly curved rod, and motile by a single polarly inserted flagellum. The colony was smooth, bright pink, and slimy. The guanine plus cytosine content of the KNA was 66%. The cell was obigately aerobic and exhibited both catalase and oxidase activities. Carotenoid pigment and poly-$\beta$-hydroxybutyrate were present. It was found to have three kinds of plasmid with molecular weights 45,000, 38,500 and 23,000. Growth with methanol(0.5%) was fast ($t_{d}$=6.5h) and was optimal at $30^{\circ}C$ and at pH 7.0. The isolate could grow on several sugars, organic acids, amino acids, amines, and alcohols in addition to the methanol. Methanol was found to be assimilated through the serine pathway.

• Korean Journal of Social Welfare
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• v.65 no.1
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• pp.201-226
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• 2013

This study aims to identify changes in early work career of youth cohort entering the labor market pre and post-the economic crisis and compare career pathway types of different cohorts. Labor market experiences of youth cohort were constructed by sequencing the number of organizations, kinds of jobs, the scale of the business, and type of employment. In addition, a holistic sequence was created by including complementary factors. In this sense, the labor market experience in this study was conceptualized as a process involving continuous sequences and hierarchical and orderly changes which differs from a simple job mobility. Sequence analysis involving Optimal Matching method was conducted to examine whether such cohort-differences in labor market experiences were related to differences in distribution of career pathway types. The result showed that the post-economic crisis cohort had a relatively higher likelihood of falling into the non-employment type, unemployment type, non-corporate employment type, irregular employment type, and mobile employment type. These findings provide empirical evidence supporting the hypothesis that the employment precariousness of cohort has exacerbated after the economic crisis.

• KSBB Journal
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• v.19 no.6 s.89
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• pp.467-470
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• 2004

We have investigated the key parameters affecting ATP regeneration in a cell-free protein synthesis system derived from Escherichia coli. When glucose-6-phosphate was used as an energy source, the efficiency of ATP regeneration sharply responded to pH change of reaction mixture. In addition, both productivity and reproducibility of protein synthesis was substantially enhanced by introducing appropriate amount of NAD into the reaction mixture. As a result, through the activation of glycolytic pathway under an optimal pH, the batch cell-free system produced over $300\;{\mu}g$ of protein in a 1 mL reaction.

• Journal of Microbiology and Biotechnology
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• v.30 no.12
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• pp.1801-1809
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• 2020

Chikungunya virus (CHIKV) was first identified in 1952 as a causative agent of outbreaks. CHIKV is transmitted by two mosquito species, Aedes aegypti and A. albopictus. Symptoms after CHIKV infection in human are typically fever and joint pain, but can also include headache, muscle pain, joint swelling, polyarthralgia, and rash. CHIKV is an enveloped single-stranded, positive-sense RNA virus with a diameter of approximately 70 nm. The pathogenesis of CHIKV infection and the mechanism by which the virus evades the innate immune system remain poorly understood. Moreover, little is known about the roles of CHIKV-encoded genes in the viral evasion of host immune responses, especially type I interferon (IFN) responses. Therefore, in the present study, we screened CHIKV-encoded genes for their regulatory effect on the activation of nuclear factor kappa B (NF-κB), a critical transcription factor for the optimal activation of IFN-β. Among others, non-structural protein 2 (nsP2) strongly inhibited melanoma differentiation-associated protein 5 (MDA5)-mediated induction of the NF-κB pathway in a dose-dependent manner. Elucidation of the detailed mechanisms of nsP2-mediated inhibition of the MDA5/RIG-I signaling pathway is anticipated to contribute to the development of virus-specific therapeutics against CHIKV infection.

• Journal of Ginseng Research
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• v.46 no.2
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• pp.283-289
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• 2022

Background: Sarcopenia, defined as loss of muscle mass and strength with age, becomes a public health concern as the elderly population increases. This study aimed to determine whether the mixture of soluble whey protein hydrolysate (WPH) and Panax ginseng berry extract (GBE) has a synergetic effect on sarcopenia and, if so, to identify the relevant mechanisms and optimal mixing ratio. Methods: In the first experiment, C57BL/6 mice were hindlimb immobilized for one-week and then administered WPH 800 mg/kg, GBE 100 mg/kg, WPH 800 mg/kg+ GBE 100 mg/kg mixture, and Fructus Schisandrae extract (SFE) 200 mg/kg for two weeks. In the second experiment, experimental design was same, but mice were administered three different doses of WPH and GBE mixture (WPH 800 mg/kg+ GBE 100 mg/kg, WPH 800 mg/kg+ GBE 90 mg/kg, WPH 1000 mg/kg+ GBE 75 mg/kg). Results: In the first experiment, we confirmed the synergetic effect of WPH and GBE on muscle mass and identified that GBE was more effective on the protein synthesis side, and WPH tended to be slightly more effective for protein degradation. In the second experiment, among three different ratios, the WPH 800 mg/kg+ GBE 100 mg/kg was most effective for muscle mass and strength. The mixtures activated muscle protein synthesis via PI3K/Akt/mTORc1 pathway and inhibited muscle protein degradation via suppressing ubiquitin-proteasome system (UPS) and autophagy-lysosome system (ALS), and these effects were more GBE dose-dependent than WPH. Conclusion: The WPH and GBE mixture having a synergetic effect is a potential agent to prevent sarcopenia.