• Nuclear Engineering and Technology
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• v.1 no.1
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• pp.23-31
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• 1969

Whole cure shrimp, eviscerated common squid and little squid meats were irradiated with gamma radiation from 60Co using varying dose up to one Mrad. Changes in quality were assessed by organoleptic, chemical (VRS and TMA-N), biochemical (hypoxanthine) and microbiological tests； and the effect of radiation on prolonging of the storage life at 2-4 C was studied. With the cure shrimp, 0.12-0.20 Mrad appears to be optimal with 8 days of storage life, whereas the unirradiated control samples had a storage life of 3 days. With the common squid meat, 0.20-0.30 Mrad appears to be optimal with 14-21 days of storage life, where-as the unirradiated control samples had a storage life of 8 days. And for the little squid meat, 0.12-0.20 Mrad appears to be optimal with 10 days of storage, where-as the unirradiated control samples had a storage life of 5 to 6 days.

• Journal of Hydrogen and New Energy
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• v.14 no.2
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• pp.155-170
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• 2003

$Cu-Ce/{\gamma}-Al_2O_3$ based catalysts were prepared and tested for selective oxidation of CO in a $H_2$-rich stream(1% CO, 1% $O_2$, 60% $H_2$, $N_2$ as balance). The effects of Cu loading and weight ratio(=Cu/(Cu+Ce)) upon both activity and selectivity were investigated upon the change in temperatures, It was also examined how the activity and selectivity of catalysts were varied with the presence of $CO_2$ and $H_2O$ in the reactant feed. Among the various Cu-Ce catalysts with different catalytic metal composition, Cu-Ce(4 : 16 wf%) /${\gamma}-Al_2O_3$ catalyst showed the highest activity(>$T_{99}$) and selectivities(50-80%) under wide range of temperatures($175-220^{\circ}C$). However, in the Cu-Ce(4 : 16 wt%)/ ${\gamma}-Al_2O_3$, the presence of $CO_2$ and $H_2O$ in the reactant feed decreased the activity and the maximum activity(>$T_{99}$) in terms of reaction temperature moved by about $25^{\circ}C$ toward higher temperature, the $T_{>99}$ window was seen between $210-230^{\circ}C$ (selectivity 50-75%). From $CO_2-/H_2O-TPD$, it can be concluded that the main cause for the decrease in catalytic activity may be attributed to the blockage of the active sites by competitive adsorption of water vapor and $CO_2$ with the reactant at low temperatures.

• Nuclear Engineering and Technology
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• v.56 no.7
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• pp.2740-2747
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• 2024

The sintering process acquired ferromagnetic copper ferrite ceramic material with a small concentration of Ni ion at 1100 ℃ for 1 h. Previously, copper ferrite with Ni proportions powder was acquired by the wet chemical process according to the relation CuFe_2-xNi_xO₄ where x takes values 0.0, 0.015, 0.03, 0.04, and 0.05. The role of Ni ion in the copper ferrite structure was investigated by X-ray analysis, Scanning electron microscope, EDX analysis, and density measurements. The gamma-ray shielding properties for the fabricated CuFeNiO ceramics samples were evaluated using the Monte Carlo simulation method. The obtained results show an enhancement in the linear attenuation coefficient for the fabricated ceramics with increasing the insertions of Ni ions within the fabricated samples, where increasing the Ni ions concentration between 0 and 1.19 wt% increases the linear attenuation by between 1.581 and 1.771 cm^-1 (at 0.103 MeV), 0.304-0.338 cm^-1 (at 0.662 MeV), and 0.160-0.178 cm^-1 (at 2.506 MeV), respectively. Simultaneously, the radiation protection efficiency for a 1 cm thickness of the fabricated samples increased between 14.8 and 16.3% with increasing the Ni ions between 0 and 1.19 wt%. Although the Ni doping concentration does not exceed 1.5 wt% of the total composition of the fabricated ceramics, the shielding capacity of the fabricated ceramics was enhanced by more than 11%, along the studied energy interval. Therefore, the fabricated samples can be used in gamma-ray shielding applications.

• Animal Bioscience
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• v.36 no.6
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• pp.851-860
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• 2023

Objective: This study aims to evaluate the target genes of gga-miR-20a-5p and the regulated immune responses in the chicken macrophage cell line, HD11, by the exosome-mediated delivery of miR-20a-5p. Methods: Exosomes were purified from the chicken macrophage cell line HD11. Then, mimic gga-miR-20p or negative control miRNA were internalized into HD11 exosomes. HD11 cells were transfected with gga-miR-20a-5p or negative control miRNA containing exosomes. After 44 h of transfection, cells were incubated with or without 5 ㎍/mL poly(I:C) for 4 h. Then, expression of target genes and cytokines was evaluated by quantitative realtime polymerase chain reaction. Results: Using a luciferase reporter assay, we identified that gga-miR-20a-5p directly targeted interferon gamma receptor 2 (IFNGR2), mitogen-activated protein kinase 1 (MAPK1), mitogen-activated protein kinase kinase kinase 5 (MAP3K5), and mitogen-activated protein kinase kinase kinase 14 (MAP3K14). Moreover, the exosome-mediated delivery of gga-miR-20a-5p successfully repressed the expression of IFNGR2, MAPK1, MAP3K5, and MAP3K14 in HD11 cells. The expressions of interferon-stimulated genes (MX dynamin like GTPase 1 [MX1], eukaryotic translation initiation factor 2A [EIF2A], and oligoadenylate synthase-like [OASL]) and proinflammatory cytokines (interferon-gamma [IFNG], interleukin-1 beta [IL1B], and tumor necrosis factor-alpha [TNFA]) were also downregulated by exosomal miR-20a-5p. In addition, the proliferation of HD11 cells was increased by exosomal miR-20a-5p. Conclusion: The exosome-mediated delivery of gga-miR-20a-5p regulated immune responses by controlling the MAPK and apoptotic signaling pathways. Furthermore, we expected that exosomal miR-20a-5p could maintain immune homeostasis against highly pathogenic avian influenza virus H5N1 infection by regulating the expression of proinflammatory cytokines and cell death.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.1
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• pp.93-97
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• 2009

Purpose: Recognize circulation work system and fixing work system's merits and demerits that is enforced in operation of PET/CT center in sudden increase recently. Wish to estimate connectivity degree of individual exposure dose and PET/CT working that is managed periodically through this and look for operation efficiency of PET/CT center. Materials and Methods: (1) Find interrelationship of length of service to be individual exposure dose and PET/CT through TLD interpretation. Specially, evaluate on the basis of data of 2.5 years until 2 quarters 2006~2008 year that show patient increase rapidly the latest. (2) Recognize what countermeasure is evaluating problems happened at circulation work system and fixing work system. Results: Patient examination's number was 14,674 items until 2 quarters 2006~2008 year, and the $^{18}F$-FDG average injection amount was 461.5 MBq. 2 people of 10 radiotechnologist did fixing work PET area and GAMMA area each, and 8 people did circulation work of 3 times for 2.5 years. Average exposure dose that PET area and Gamma area's circulation men in service receive was 1.32 mSv, and PET area men in services came out average 0.825 mSv high than Gamma area men in services. Nurse's exposure dose is 0.28 mSv, and next 2 reason is conjectured. One is contact with patient that medicate $^{18}F$-FDG injection, and another is consultation about patient's next time schedule after examination end. Although exposure dose's amount is not much, is expected to consider continuation work possibility by exposure dose in case is a nurse with pregnancy possibility. Also, $^{131}I$-isotope therapy area's radiotechnologist that use capsule appeared by 0.12 mSv and a nuclear medicine doctor appeared by exposure dose that is less of 0.11 mSv. Conclusions: In case do PET/CT center circulation work after a long time, connoted danger that most men in service is consecutiveness deficiency of business and individual exposure dose increase at early 1 month. Specially, way for individual exposure dose's decrease should be considered. Also, need to evaluate abhorrent work form for efficient work system introduction, and enforce circulation and fixing work suggestion suitable shift working. Finally, must make normalized business guide and so on to prevent circulation work people's business efficiency decline.

• KSBB Journal
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• v.24 no.6
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• pp.549-555
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• 2009

4 kinds of Regional Special Natural Products (RSNPs), such as Anthrisci radix, Psoraleae semen, Siegesbeckiae herba and Corni fructus were examined to verify for anti-obesity effect. $PPAR\gamma$ (peroxisome proliferator-activated receptor $\gamma$) from 3T3-L1 cell concerning adipocyte differentiation was suppressed by different concentraton of 4 RSNPs with western blot, when treated RSNPs' extract and MDI (IBMX, Dexamethasone, Insulin) at the same time. Also, SREBP-1 (Sterol regulatory element binding protein) controlling lipogenesis and $PPAR\gamma$ expression levels were reduced by these 4 RSNPs' extract, when these chemicals after differentiation of 3T3-L1 cell. And lipid droplets were reduced by 7.5%, 14.4%, 18.3% and 30% at different concentration of Anthrisci radix from Oil Red O staining. Also, it was reduced by 2%, 4.9%, 9.3% and 38% at different concentration of Psoraleae semen. For Siegesbeckiae herba, it was inhibited by 1.4%, 6.4%, 16.4% and 30.1%, respectively. And Corni fructus was also showed by 0.9%, 6.3%, 13.7% and 33% at same concentration of Siegesbeckiae herba. These 4 kinds of RSNPs were expected for a useful material for anti-obesity materials.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.75-75
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• 1993

The general pharmacological profiles of SKI 2053R were investigeted on the central nervous system, autonomic nervous system, respiratory-cardiovascular system, digestive system and other systems. SKI 2053R had no significant pharmacological effects. Pharmacokinetic studies on time-course of blood levels, tissue distribution and excretion of SKI 20S3R were performed in rats and beagle dogs after intravenous administration of $^{14}$ C-labeled SKI 2053R. The blood level of radioactivity decreased in bi-or tri-exponential manners: rapidly decreased at $\alpha$-phase but slowly decreased at $\beta$-or ${\gamma}$-phase. $^{14}$ C SKI 2053R was well distributed to all tissues except central nervous system. Tissue concentration profiles of radioactivity were almost consistent wi th those of blood, but higher than those of plasma from 1 to 168 hrs after administration. Also, these results were consistent wi th those of whole body ARG study. The urinary and fecal excretions of radioactivity within 168 hr after administration were 84-87 and 9-11 ％ of total radioactivity of $^{14}$ C-SKI 2053R administered. In lactating rats, the levels of radioactivity in the milk were significantly lower than that in the blood, but slightly higher than that in the plasma. The disapperance of the radioactivity from the milk was similar as that in the plasma.

• Journal of Sericultural and Entomological Science
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• v.14 no.1
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• pp.9-13
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• 1972

On the seventh day of mounting male and feamale cocoons are distinguished. A part of those male and female pupae is irradiated for 40 min. with 1,000r-ray irradiation. Those eggs obtained from the irradiated pupae are divided into six groups of 5, 15, 45, 90, 720 and 2,400 minutes after laying. The cahanges of accid soluble phosphorus in the each group of eggs are as follows. 1. In the control group of the maximum quantity in acid soluble phosphorus was 1,456r/100mg D.P. in the 2,400 minutes group, while the minimum quantity was 1,233r/100mg D.P. in the 720 minutes group. 2. In the mated group of ＊irradiated female moths and control male moths, the quantity of acid soluble phoshorus was small as compared with the control group in the five minute group of 1,288r/100mg D.P. and in the 15 minutes group of 1,299r/100mg D.P. while the quantity increased to 1,484r/100mg D.P. in the 45 minutes group. The quantity began to decrease again to 1,400r/100mg D.P. in the 2,400 minutes group which was smaller than that of the control group. The quantity was slightly small in the silkworm eggs laid in the early stage when compared with that of mated group of ＊irradiated male moths and control female moths. Both groups showed the larger quantity in the 720 minutes group than that of the control group. The quantity of acid soluble phosphorus in the mated group of control female moths .and ＊irradiated male moths was larger in variation than in the mated group of control male moths and ＊irradiated female moths. 3. In the mated group of ＊irradiated male and female moths the largerst quantity was 1,760r/100ms D.P. in 2,400 minutes group and second was 1,736r/100mg D.P. in 90 minutes group, and third was 1,288r/100mg D. P., in 5 minutes group. Generally the quantity was small in silkworm eggs laid by the irradiated one in the early stage than the control group, but in the later period of egg the quantity began to increase more than that of control group.

• The Journal of the Acoustical Society of Korea
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• v.14 no.1
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• pp.48-55
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• 1995

The capacity of a digital cellular CDMA system is evaluated by computer simulation for reverse link (mobile-to-base) with 37 hexagonal cells including 3 rings from a center cell. It is assumed that the channels have shadow fading and the system is ideally power controlled. In this paper the capacity of CBMA system is evaluated for various propagation exponents, voice activity factors and neighboring cell traffics. The following results are obtained. The capacity of CDMA system is increased according to the increase of the propagation exponents and the decrease of the voice activity factors. Its capacity is about 15 and 5 times larger thari that of analog cellular FM/FDMA and digital cellular TDMA for $\gamma=4$ respectively, and is very sensitive to the neighboring cell traffics.

• Food Science and Biotechnology
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• v.14 no.2
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• pp.181-184
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• 2005

Effects of irradiation and fumigation on disinfestation and quality attributes of chestnuts during storage were studied. Fresh chestnuts were exposed to gamma irradiation (0-10 kGy) and methyl bromide (MeBr) under commercial conditions and stored at different temperatures for 6 months. Pest of quarantine importance for chestnuts, Curculio sikkimensis Heller showed 100% mortality by MeBr on 3rd day after fumigation and by irradiation at 0.5 kGy in about 3 weeks at $23{\pm}0.5^{\circ}C$. Respiration rates of samples one day after treatments increased in proportion to irradiation dose. Respiration pattern of MeBr group was equal to that of 10 kGy-group. Both MeBr and irradiation at 0.25 kGy or higher showed 100% inhibition of sprouting during storage at $5^{\circ}C$ for 6 months. Flesh firmness was significantly reduced by MeBr or irradiation over 5 kGy (p<0.05) 1 day after treatments. MeBr fumigation resulted in appreciable decrease in flesh weight, reducing sugar and ascorbic acid contents (p<0.05), as compared to irradiated samples. Irradiation at 0.5 kGy was effective as alternative to MeBr in controlling pests while maintaining overall quality of fresh chestnuts during storage.