• Proceedings of the Korean Geotechical Society Conference
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• 1995.10a
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• pp.36-46
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• 1995

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1985.10a
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• pp.49-52
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• 1985

• Proceedings of the Korean Nuclear Society Conference
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• 1999.10a
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• pp.304.2-304
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• 1999

• The Korean Journal of Physiology and Pharmacology
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• v.9 no.5
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• pp.291-298
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• 2005

To characterize cytosolic $Ca^{2+}$ fluctuations under metabolic inhibition, rat ventricular myocytes were exposed to $200{\mu}M$ 2,4-dinitrophenol (DNP), and mitochondrial $Ca^{2+}$, mitochondrial membrane potential (${\Delta}{\Psi}m$), and cytosolic $Ca^{2+}$ were measured, using Rhod-2 AM, TMRE, and Fluo-4 AM fluorescent dyes, respectively, by Laser Scanning Confocal Microscopy (LSCM). Furthermore, the role of sarcolemmal $Na^+$/$Ca^{2+}$ exchange (NCX) in cytosolic $Ca^{2+}$ efflux was studied in KB-R7943 and $Na^+$-free normal Tyrode's solution (143 mM LiCl ). When DNP was applied to cells loaded with Fluo-4 AM, Fluo-4 AM fluorescence intensity initially increased by $70{\pm}10$% within $70{\pm}10$ s, and later by $400{\pm}200$% at $850{\pm}45$ s. Fluorescence intensity of both Rhod-2 AM and TMRE were initially decreased by DNP, coincident with the initial increase of Fluo-4 AM fluorescence intensity. When sarcoplasmic reticulum (SR) $Ca^{2+}$ was depleted by $1{\mu}M thapsigargin plus $10{\mu}M ryanodine, the initial increase of Fluo-4 AM fluorescence intensity was unaffected, however, the subsequent progressive increase was abolished. KB-R7943 delayed both the first and the second phases of cytosolic $Ca^{2+}$ overload, while $Na^+$-free solution accelerated the second. The above results suggest that: 1) the initial rise in cytosolic $Ca^{2+}$ under DNP results from mitochondrial depolarization; 2) the secondary increase is caused by progressive $Ca^{2+}$ release from SR; 3) NCX plays an important role in transient cytosolic $Ca^{2+}$ shifts under metabolic inhibition with DNP.

• Korean Chemical Engineering Research
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• v.55 no.3
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• pp.363-368
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• 2017

Methylotrophy is able to use reduced one-carbon compound, such as methanol and methylamine, as a sole carbon source. Methylobacterium extorquens AM1 is the most extensively studied methylotroph utilizing serine-isocitrate lyase cycle. Because the Poly 3-hydroxybutyrate (PHB) synthesis pathway in M. extorquens AM1 is likely to interlink with EMCP (ethylmalonyl-CoA pathway), glyoxylate, and TCA cycles, regulation of PHB production is needed to produce EMCP-derived acid or TCA acids. To adjust carbon flux to PHB production, PhaR, which seems to have function of regulator of PHB synthesis and acetyl-CoA flux, was knocked out in M. extorquens AM1 by using markerless gene deletion methods. As a result, PHB granules were remarkably reduced in the knockout strain ${\Delta}phaR$ compared to parental strain. Although lag phase was extended for 12h, ${\Delta}phaR$ showed similar cell growth and methanol consumption rate compared to wild type.

• Applied Chemistry for Engineering
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• v.7 no.1
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• pp.153-161
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• 1996

Several main nuclides($^{241}Am$, $^{152}Eu$ and $^{237}Np$) in radioactive waste solution were selected and examined to mutual separation with di-(2-ethylhexyl) phosphoric acid by solvent extraction technique. $^{237}Np$ was extracted more than 99.9% adding the $H_2O_2$ that was a good reductant for the oxidation state control of $^{237}Np$. $^{241}Am$, $^{152}Eu$ and $^{237}Np$ could be fairly well separated one another during the different sequence stripping stages, but about 7~9.6% of the other nuclides were still remained for the $^{241}Am$ stripping solution. This result shows that the product of $^{152}Eu$ and $^{237}Np$ was good, but $^{241}Am$ may be needed to further purification process. It was also discussed on the cause of the third phase formation phenomenon that was found in the solvent regeneration.

• Journal of Korean Neurosurgical Society
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• v.30 no.9
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• pp.1103-1107
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• 2001

Objective : Atypical and malignant meningiomas(AM, MM) are known to be rare and show aggressive behavior. Limited data are available concerning the clinical features, effectiveness of surgical removal and role of radiation therapy with AM, MM. The authors report our experience of AM, MM, with respect to clinical features. Methods : Twenty-four cases of AM and 28 cases of MM, who were operated between 1988 and 1999 were retro-spectively studied review of medical records and radiological findings. These were compared with control group of 24 cases of menigiomas manifestating usual clinical course, which are selected arbitrarily among operative cases between Apr. 1999 and Dec. 1999. Mean follow-up periods were 26(1-91) months for AM and 23(1-62) for MM. Authors analyzed the prognostic factors for survival, and statistical analysis were accomplished by Kaplan-Meier method and log-rank test. Results : Differences of clinical features between control groups and these atypical and malignant meningioma group were not significant. However, the location of MM was frequent in non-basal area(p<0.01). In AM, there were 4 patients of recurrence, and 3 patients of mortality. Among mortality cases, only one patient died of tumor progression, the other patients died of other causes. The survival at 2 year and 5 year in this group were 88% and 74% respectively, and in MM, 11 patients died due to tumor progression and 2 had spinal metastasis. The survival at 2 year and 5 year were 72% and 20%, respectively. For extent of resection, total removal(Simpson grade 1 or 2) was less often achieved in MM compared with AM(50% vs. 83%). Extent of resection of tumor and postoperative radiation therapy did not affect survival in both AM, MM. Conclusions : Clinical behavior of AM showed more benign than that of MM. Prognostic factor for survival is not related extent of resection of tumor and postoperative radiation therapy. However, further investigation with long-term follow-up and additional cases is mandatory.

• Journal of Veterinary Clinics
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• v.32 no.2
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• pp.135-140
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• 2015

Trans-10, cis-12-conjugated linoleic acid (t10c12-CLA) has been shown to participate in the regulation of anti-inflammatory effects. The objectives of this study were to examine the effects of t10c12-CLA on reactive oxygen species (ROS) and nitric oxide (NO) production and nuclear factor-kappaB (NF-${\kappa}B$) activation in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and to determine whether these effects were associated with change of intracellular calcium ion ($Ca^{2+}$). ROS production was increased in LPS-stimulated RAW 264.7 cells, and this effect was suppressed by 1,2-bis-(o-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA/AM), a calcium chelator. t10c12-CLA suppressed ROS production in LPS-stimulated RAW 264.7 cells, which was further more decreased by treatment with BAPTA/AM. These indicated that t10c12-CLA decreases $Ca^{2+}$-dependent ROS production in LPS-stimulated RAW 264.7 cells. Similarly, NF-${\kappa}B$ p65 DNA binding activity and NO production were decreased by treatment with either t10c12-CLA, BAPTA/AM, or t10c12-CLA and BAPTA/AM combination. However, there were no differences between t10c12-CLA and BAPTA/AM treatment in NO production of LPS-stimulated RAW 264.7 cells. These data indicate that t10c12-CLA inhibits the increases in ROS and NO production and the NF-${\kappa}B$ activation in LPS-stimulated condition. These results suggested that CLA exerts potent anti-inflammatory effects by suppression of LPS-induced ROS and NO production, and NF-${\kappa}B$ activationn via $Ca^{2+}$-dependent pathway.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.4
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• pp.191-202
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• 2001

Experiments were conducted on established grassland sward at Gongiam, Kwangju, and Kyung-gi in Korea from 1995 to 1997. The influence of mineral-N fertilizer or animal manure(AW) on herbage dry matter(DM) yield, N yield, the recovery of AM-N, and soil N and organic matter(0M) content in the mixed sward('potomac' orchardgrass, 'fawn' tall fescue, and 'kenblue' Kentuky bluegrass) was investigated. The treatments were replicated three times in a split plot block design. AM(the main plots) was applied at 200kg N ha ' year ' on each plot. The types of AM were cattle feedlot manure(CFM), pig manure fermented with sawdust(PMFS) and Korea native cattle slurry(KNCS). Three levels of mineral-N fertilizer, as urea, ranging from 0 to 200kg N $ha^{-1}\;year^{-1}$ in 100kg increments, were superimposed on each plot. The fertilizers and AM were applied in two equal dressings(the end of March and middle of November). AM and mineral fertilizer had significant effects(p<0.05) on herbage DM and N yields. Herbage yields in KNCS were higher than those in CFM and PMFS(p

• Safety and Health at Work
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• v.10 no.2
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• pp.229-236
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• 2019

Background: Emerging reports suggest the potential for adverse health effects from exposure to emissions from some additive manufacturing (AM) processes. There is a paucity of real-world data on emissions from AM machines in industrial workplaces and personal exposures among AM operators. Methods: Airborne particle and organic chemical emissions and personal exposures were characterized using real-time and time-integrated sampling techniques in four manufacturing facilities using industrial-scale material extrusion and material jetting AM processes. Results: Using a condensation nuclei counter, number-based particle emission rates (ERs) (number/min) from material extrusion AM machines ranged from $4.1{\times}10^{10}$ (Ultem filament) to $2.2{\times}10^{11}$ [acrylonitrile butadiene styrene and polycarbonate filaments). For these same machines, total volatile organic compound ERs (${\mu}g/min$) ranged from $1.9{\times}10^4$ (acrylonitrile butadiene styrene and polycarbonate) to $9.4{\times}10^4$ (Ultem). For the material jetting machines, the number-based particle ER was higher when the lid was open ($2.3{\times}10^{10}number/min$) than when the lid was closed ($1.5-5.5{\times}10^9number/min$); total volatile organic compound ERs were similar regardless of the lid position. Low levels of acetone, benzene, toluene, and m,p-xylene were common to both AM processes. Carbonyl compounds were detected; however, none were specifically attributed to the AM processes. Personal exposures to metals (aluminum and iron) and eight volatile organic compounds were all below National Institute for Occupational Safety and Health (NIOSH)-recommended exposure levels. Conclusion: Industrial-scale AM machines using thermoplastics and resins released particles and organic vapors into workplace air. More research is needed to understand factors influencing real-world industrial-scale AM process emissions and exposures.