• Nuclear Engineering and Technology
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• v.54 no.6
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• pp.2135-2146
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• 2022

A nuclear energy facility is one of the most critical facilities to be safely protected during and after operation because the physical destruction of its barriers by an external attack could release radioactivity into the environment and can cause harmful effects. The barrier walls of nuclear energy facilities should be sufficiently robust to protect essential facilities from external attack or sabotage. Physical protection system (PPS) vulnerability assessment of a typical small nuclear research reactor was carried out by simulating an external attack with a tri-nitro toluene (TNT) shaped charge and results are presented. The reinforced concrete (RC) barrier wall of the research reactor located at a distance of 50 m from a TNT-shaped charge was the target of external attack. For the purpose of the impact assessment of the RC barrier wall, a finite element method (FEM) is utilized to simulate the destruction condition. The study results showed that a hole-size of diameter 342 mm at the front side and 364 mm at the back side was created on the RC barrier wall as a result of a 143.35 kg TNT-shaped charge. This aperture would be large enough to let at least one person can pass through at a time. For the purpose of the PPS vulnerability assessment, an Estimate of Adversary Sequence Interruption (EASI) model was used, which enabled the determination of most vulnerable path to the target with a probability of interruption equal to 0.43. The study showed that the RC barrier wall is vulnerable to a TNT-shaped charge impact, which could in turn reduce the effectiveness of the PPS.

• Journal of Environmental Science International
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• v.31 no.1
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• pp.77-85
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• 2022

Environmental contamination by organic compounds are not only restricted to water, but extends to soil and groundwater as well. However, highly oxidized compounds, such as halogenated organics and nitro-compounds, can be detoxified employing reducing methods. Permeable reactive barrier is one of the representative technologies where zero-valent metals (ZVMs) are employed for groundwater remediation. However, organics contaminates often contaminate the unsaturated zone above the groundwater. Despite the availability of technologies like soil vapor extraction and bioremediation, removing organic compounds from this zone represents several challenges. In this study, the reduction of nitrobenzene to aniline was achieved using zero-valent iron (ZVI) under unsaturated conditions. Results indicated that the water content was an important variable in this reaction. Under dry conditions (water content = 0.2%), the reduction reaction was inhibited; however, when the water content was between 10% and 25% (saturated condition), ZVI can reduce nitrobenzene. Palladized iron (Pd/Fe) can be used to reduce nitrobenzene when the water content is between 2.5% and 10%. The reaction was evaluated over a wide range of temperatures (10 - 40 ℃), and the results indicated that increasing the temperature resulted in increased reaction rates under unsaturated conditions.

• The Korean Journal of Pain
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• v.35 no.4
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• pp.413-422
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• 2022

Background: The neocortex, including the medial prefrontal cortex (mPFC), contains many neurons expressing nitric oxide synthase (NOS). In addition, increasing evidence shows that the nitric oxide (NO) and opioid systems interact in the brain. However, there have been no studies on the interaction of the opioid and NO systems in the mPFC. The objective of this study was to investigate the effects of administrating L-arginine (L-Arg, a precursor of NO) and N(gamma)-nitro-L-arginine methyl ester (L-NAME, an inhibitor of NOS) into the mPFC for neuropathic pain in rats. Also, we used selective opioid receptor antagonists to clarify the possible participation of the opioid mechanism. Methods: Complete transection of the peroneal and tibial branches of the sciatic nerve was applied to induce neuropathic pain, and seven days later, the mPFC was cannulated bilaterally. The paw withdrawal threshold fifty percent (50% PWT) was recorded on the 14th day. Results: Microinjection of L-Arg (2.87, 11.5 and 45.92 nmol per 0.25 µL) increased 50% PWT. L-NAME (17.15 nmol per 0.25 µL) and naloxonazine (an antagonist of mu opioid receptors, 1.54 nmol per 0.25 µL) inhibited anti-allodynia induced by L-Arg (45.92 nmol per 0.25 µL). Naltrindole (a delta opioid receptor antagonist, 2.45 nmol per 0.25 µL) and nor-binaltorphimine (a kappa opioid receptor antagonist, 1.36 nmol per 0.25 µL) were unable to prevent L-Arg (45.92 nmol per 0.25 µL)-induced antiallodynia. Conclusions: Our results indicate that the NO system in the mPFC regulates neuropathic pain. Mu opioid receptors of this area might participate in pain relief caused by L-Arg.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.2
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• pp.125-133
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• 2022

Carbon monoxide (CO) is a known gaseous bioactive substance found across a wide array of body systems. The administration of low concentrations of CO has been found to exert an anti-inflammatory, anti-apoptotic, anti-hypertensive, and vaso-dilatory effect. To date, however, it has remained unknown whether CO influences atrial natriuretic peptide (ANP) secretion. This study explores the effect of CO on ANP secretion and its associated signaling pathway using isolated beating rat atria. Atrial perfusate was collected for 10 min for use as a control, after which high atrial stretch was induced by increasing the height of the outflow catheter. Carbon monoxide releasing molecule-2 (CORM-2; 10, 50, 100 μM) and hemin (HO-1 inducer; 0.1, 1, 50 μM), but not CORM-3 (10, 50, 100 μM), decreased high stretch-induced ANP secretion. However, zinc porphyrin (HO-1 inhibitor) did not affect ANP secretion. The order of potency for the suppression of ANP secretion was found to be hemin > CORM-2 >> CORM-3. The suppression of ANP secretion by CORM-2 was attenuated by pretreatment with 5-hydroxydecanoic acid, paxilline, and 1H-[1,2,4] oxadiazolo [4,3-a] quinoxalin-1-one, but not by diltiazem, wortmannin, LY-294002, or NG-nitro-L-arginine methyl ester. Hypoxic conditions attenuated the suppressive effect of CORM-2 on ANP secretion. In sum, these results suggest that CORM-2 suppresses ANP secretion via mitochondrial K_ATP channels and large conductance Ca²⁺-activated K⁺ channels.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.6 no.2
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• pp.61-68
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• 2020

Aggregated neurofibrillary tangles (NFTs) are a pathological hallmark in Alzheimer's disease (AD) and many radiopharmaceuticals targeting NFTs have been developed so far. Among these, [¹⁸F]flortaucipir (TAUVID^TM) is the first approved radiopharmaceutical in the Food and Drug Administration (FDA) to image tau pathology. In the present study, we describe the optimized radiosynthetic method for the routine production of [¹⁸F] flortaucipir using a commercialized automation module (i.e. GE TRACERlab^TM FX_FN pro). [¹⁸F]Flortaucipir was prepared by nucleophilic substitution from its N-tert-butoxycarbonyl protected nitro precursor, tertbutyl 7-(6-nitropyridin-3-yl)-5H-pyrido[4,3-b]indole-5-carboxylate, at 130℃ for 10 min in dimethyl sulfoxide. The mean radiochemical yield was 20 ± 4.3% (decay-corrected, n = 47) with the molar activity of 218 ± 32 GBq/µmol at the end of synthesis. The radiochemical purity was determined to be above 95%. The overall production time including quality control is approximately 100min. The final produced [¹⁸F]flortaucipir injection meets the USP criteria for quality control. Thus, this fully automated system is validated for clinical use.

• Korean Journal of Food Science and Technology
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• v.54 no.1
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• pp.59-65
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• 2022

Curcuminoids in turmeric oleoresin (TO) are known to be effective antioxidants; they exhibit photosensitizing properties under light. In this study, the photoreactive properties of TO and its consequent induction of lipid peroxidation and cytotoxicity were evaluated. TO exhibited photosensitizing activities as evidenced by the reduction of nitro blue tetrazolium and by the decolorization of formazan under light, whereas light-irradiated TO did not enhance the levels of reactive oxygen species. The levels of hydroperoxide and thiobarbituric acid reactive substance (TBARS) were significantly elevated under a fluorescent light (10 W/m²) in corn, canola, and soybean oils containing 10-40 and 20-80 ㎍/mL of TO (p<0.05) but not in olive oil. Canola oil was the most sensitive to photo-oxidation induced by TO. The level of TBARS from linoleic acid in the oil in water system was, however, decreased by TO under light. The cytotoxicity effect of TO on melanoma cells was also substantially enhanced under light.

• Korean Journal of Exercise Nutrition
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• v.23 no.4
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• pp.26-31
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• 2019

[Purpose] Numerous epidemiological studies have shown that it is possible to prescribe exercise for neurodegenerative disease, such as Alzheimer's disease and Parkinson's disease. However, despite the availability of diverse scientific knowledge, the effects of exercise in this regard are still unclear. Therefore, this study attempted to investigate a substance, such as black chokeberry (Aronia melanocapa L.) that could improve the ability of the treatment and enhance the benefits of exercising in neurodegenerative diseases. [Methods] The cell viability was tested with 2,3-bis[2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolim-5-carboxanilide and the cells were stained with ethidium homodimer-1 solution. The mRNA expression levels were evaluated by microarray. The active compounds of black chokeberry ethanolic extract (BCE) were analyzed by gas chromatography. The chemical shift analysis in the brain was performed using magnetic resonance spectroscopy. [Results] BCE treatment decreased hydrogen peroxide-induced L6 cell death and beta amyloid induced primary neuronal cell death. Furthermore, BCE treatment significantly reduced the mRNA levels of the inflammatory factors, such as IL-1α, Cxcl13, IL36rn, Itgb2, Epha2, Slamf8, Itgb6, Kdm6b, Acvr1, Cd6, Adora3, Cd27, Gata3, Tnfrsf25, Cd40lg, Clec10a, and Slc11a1, in the primary neuronal cells. Next, we identified 16 active compounds from BCE, including D-mannitol. In vivo, BCE (administered orally at a dosage of 50 mg/kg) significantly regulated chemical shift in the brain. [Conclusion] Our findings suggest that BCE can serve as a candidate for neurodegenerative disease therapy owing to its cyto-protective and anti-inflammatory effects. Therefore, BCE treatment is expected to prevent damage to the muscles and neurons of the athletes who continue high intensity exercise. In future studies, it would be necessary to elucidate the effects of combined BCE intake and exercise.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.143-143
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• 2022

Plant defense systems against pathogens have been studied extensively and are currently a hot topic in plant science. Using a reverse genetics technique, this study looked into the involvement of the NO-downregulated NAD(P)-binding Rossmann-fold superfamily gene in plant growth and defense in Arabidopsis thaliana. For this purpose, the knockout and overexpressing plant of the candidate gene along with the relevant controls were exposed to control, oxidative and nitro-oxidative stresses. The results showed that candidate gene negatively regulates plants' root and shoot lengths. To investigate the role of the candidate gene in plant basal defense, R-gene-mediated resistance and systemic acquired resistance (SAR) plants were challenged with virulent or avirulent strains of Pseudomonas syringae pathovar tomato (Psf) DC3000. The results showed that the candidate gene negatively regulates plants' basal defense, R-gene-mediated resistance and SAR. Further characterization via GO analysis associated the candidate gene with metabolic and cellular processes and response to light stimulus, nucleotide binding and cellular location in the cytosol and nucleus. Protein structure analysis indicated the presence of a canonical Oxidoreductase family NAD (P)-binding Rossmann fold domain of 120 amino acids with a total of 121 plant homologs across 35 different plant species in the clad streptophyta. Arabidopsis eFP browser showed its expression in almost all the above-ground parts. Protein analysis indicated C225 and C359 as potential targets for S-Nitrosylation by NO. SMART analysis indicated possible interactions with mevalonate/galactokinase, galacturonic acid kinase, arabinose kinase, putative xylulose kinase, GroES-like zinc-binding alcohol dehydrogenase and various glyceraldehyde-3-phosphate dehydrogenases.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.6
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• pp.850-860
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• 2023

The effects of dietary mannan oligosaccharides, Lactobacillus plantarum, Bacillus subtilis, and Bacillus licheniformis supplementation on hybrid grouper Epinephelus akaara ♀×Epinephelus lanceolatus ♂ were evaluated. The fish were fed a basal diet and five other diets consisting of 0.6% mannan oligosaccharides, L. plantarum, B. subtilis, and B. licheniformis and mixture of each 0.15% prebiotic and all the probiotics (designated as MOS, LP, BS, BL, and SYN) for 56 days. Growth performance and feed utilization showed no significant differences among all experimental groups. Lipid level of whole-body was significantly high in MOS and BL groups. Plasma aspartate aminotransferase was significantly low in BL and SYN groups. Nitro-blue tetrazolium, lysozyme and anti-protease, and glutathione peroxidase in BS, SYN, and all probiotic groups, respectively, were significantly high. Intestinal Vibrio bacteria was significantly low in all probiotic and SYN groups. Gene expression of interleukin-1β and interleukin-10 in SYN group; transforming growth factor β2 in MOS and BS groups, toll-like receptor 2-2 in BS and BL groups; and C-type lectin in MOS, LP and SYN groups were significantly upregulated. Our findings indicate that mannan oligosaccharides, L. plantarum, B. subtilis, and B. licheniformis could improve innate immunity, antioxidant capacity, anti-inflammation, and intestinal microbiota of hybrid grouper.

• Journal of Chest Surgery
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• v.36 no.12
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• pp.887-893
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• 2003

External stimuli increases intracellular (IC) $Ca^{2+}$, which increases extracellular (EC) $K^{+}$. To verify $K^{+}$ effects on the vascular contraction, we performed an experiment using mouse aortic endothelial cell. Meterial and Method: We examined the mouse aortic contractility changes as we measured the IC $Ca^{2+}$ change and ionic current by using the voltage clamp technique under different conditions such as: increasing EC $K^{+}$, removing endothelial cell, giving L-NAME (N-nitro-L-arginine methyl ester) which suppress nitric oxide formation, Ouabain which control N $a^{+}$ - $K^{+}$ pump and N $i^{2+}$ which repress N $a^{+}$-C $a^{2+}$ exchanger Result: When we increased EC $K^{+}$ from 6 to 12 mM, there was no change in aortic contractility. Aorta contracted with more than 12 mM of EC $K^{+}$. Ace-tylcholine (ACh) induced relaxation was inhibited with EC $K^{+}$ from 6 to 12 mM, but was not found after de-endothelialization or L-NAME treatment. ATP or ACh increased IC $Ca^{2+}$ in cultured endothelium. After maximal increase of IC $Ca^{2+}$, increasing EC $K^{+}$ from 6 to 12 mM made IC $Ca^{2+}$ decrease and re-decreasing EC $K^{+}$ to 6 mM made IC $Ca^{2+}$ increase. Ouabain and N $i^{2+}$ masked the inhibitory effect of endothelium dependent relaxation by increased EC $K^{+}$. Conclusion: These data indicate that increase in EC $K^{+}$ relaxes vascular smooth muscle and reduces $Ca^{2+}$ in the endothelial cells which inhibit endothelium dependent relaxation. This inhibitory mechanism may be due to the activation of N $a^{+}$- $K^{+}$ pump and N $a^{+}$-C $a^{2+}$ exchanger. $a^{+}$-C $a^{2+}$ exchanger.r.