• Nuclear Engineering and Technology
• /
• v.50 no.3
• /
• pp.446-452
• /
• 2018

To improve the accuracy and safety of irradiation tests in High flux Advanced Neutron Application ReactOr (HANARO), the nuclear energy deposition rate, which is called nuclear heating, was estimated for an irradiation capsule with an iridium sample in the irradiation hole in order. The gamma rays emitted from the radioisotopes (RIs) of the structural materials such as flow tubes of fuel assemblies and heavy water reflector tank were considered as radiation source. Using the ORIGEN2.1 code, emission rates of delayed gamma rays were calculated in consideration of the activation procedure for 8 years and 2 months of HANARO operation. Calculated emission rates were used as a source term of delayed gamma rays in the MCNP6 code. By using the MCNP code, the nuclear heating rates of the irradiation capsules in the inner core, outer core, and heavy water reflector tank were estimated. Calculated nuclear heating in the inner core, outer core, and heavy water reflector tank were 200-260 mW, 80-100 mW, and 10 mW, respectively.

• Journal of Pharmaceutical Investigation
• /
• v.23 no.3
• /
• pp.145-153
• /
• 1993

Retaining a drug in the stomach by some means is sometimes necessary to extend the G1 absorption time of the drug more than 6-8 hrs. Hydrogel has often been examined for its feasibility as a dosage form, so called platform, that could be retained in the stomach due to its excellent swelling properties in the gastric fluid. In this study, polyvinylpyrrolidone (PVP) hydrogel crosslinked by albumin or acrylated albumin was synthesized in a tablet form and evaluated for its possibility as the platform. The synthesis of the hydrogel was performed by $^{60}Co\;{\gamma}-ray$ irradiation of N-vinyl-2-pyrrolidone (monomer) in the presence of a crosslinking agent: aqueous solution of albumin or acrylated albumin. Synthetic conditions such as radiation dose, dose rate and concentration of crosslinking agent were varied in order to optimize the swelling and mechanical properties of the hydrogels. Degree of swelling of albumin-crosslinked PVP (Al-PVP) was highly dependent on radiation dose, dose rate and albumin concentration: it was decreased as they increased. On the other hand, that of acrylated albumin-crosslinked PVP (Acryl-PVP) was almost independent on them except dose rate: it was decreased as the radiation dose rate increased. The compressive strength of the two hydrogels was decreased as the dose rate increased. Digestion of both PVP in artificial gastric fluid containing pepsin was delayed by the ${\gamma}-ray$ irradiation. In conclusion, Al-PVP and Acry-PVP with diverse swelling and mechanical properties could be obtained by controlling synthetic conditions, mainly the irradiation dose rate.

• Research in Plant Disease
• /
• v.20 no.2
• /
• pp.71-78
• /
• 2014

Gamma irradiation and its convergence with nano-silver particles and sodium dichloroisocyanurate (NaDCC) were investigated to inhibit germination and mycelial growth of Botrytis elliptica, the pathogen of lily leaf blight. In addition, the same treatments were studied on the process of disease development with detached leaf of lily cv. Siberia. Spray inoculation, which is closer to natural infection than wound inoculation, can be a way to investigate infection ability of the treated pathogen. The irradiating dose required to reduce the population by 90%, $D_{10}$, was 526 Gy irradiating with 0-2000 Gy gamma ray on the conidial suspension as well as the growing mycelia. Even at 2000 Gy, the mycelium was not killed but just delayed its growth at 1-2 days behind. Convergent treatment with 40 mg/l of NaDCC just before 200 Gy gamma irradiation was the best way to decrease the conidial germination about 1/1000 times. The control values of gamma irradiation were 23% and 19.5% at wound inoculation and spray inoculation, respectively. On wound-inoculation, the control value of NaDCC only was 89%, and that of NaDCC convergent with 200 Gy gamma irradiation was 32%. On sprayinoculation, the highest control value was NaDCC at 50%, and that of NaDCC convergent with gamma irradiation was 24%.

• Journal of Acupuncture Research
• /
• v.17 no.4
• /
• pp.28-40
• /
• 2000

Objectives : This study was purposed to investigate the effect of honey bee venom aqua-acupuncture on decreased immune response by its production from Korea, North America and China. Methods : ICR-mouse was exposed with four minute sublethal 60Co- $\gamma$ -ray irradiation onto the body and got a series of each country's 0.1 ml honey bee venom aqua-acupuncture to Choksamni(ST36) every other day for three times. Thereafter the numbers of WBC, delayed type hypersensitivity, hemagglutinin titers, hemolysin titers, quantitation of T-cell and B-cell, lymphocyte transformation, natural killer cell activity, interleukin-2 productivity and interferon productivity were measured. Results : The numbers of WBC, delayed type hypersensitivity, hemagglutinin titers, hemolysin titers, quantitation of T-cell and B-cell and lymphocyte transformation were increased respectively with statistical significance in Korean, North American and Chinese honey bee venom aqua-acupuncture groups as compared with the control group. The natural killer cell activity was increased with statistical significance in Korean honey bee venom aqua-acupuncture group, and Interleukin-2 productivity and interferon productivity were not shown any statistical significance in all experimental groups as compared with the control group. Conclusions : According to the results, honey bee venom aqua-acupuncture has significant effect on decreased immune response, and Korean bee venom can be substituted for North American and Chinese one.

• Food Science and Biotechnology
• /
• v.16 no.4
• /
• pp.594-599
• /
• 2007

In this study, we evaluated whether the oral administration of chondroitin from the cartilage of Raja kenojei is effective on the progression of rheumatoid arthritis (RA), using collagen-induced arthritic (CIA) mice. Arthritis development was delayed dose-dependently in the chondroitin-treated groups. The pre- and late-treated groups receiving 1,000 mg/kg of chondroitin had clinical scores that were reduced significantly by 56.9 (p<0.05) and 43.3% (p<0.05), respectively, compared to the vehicle-treated groups. Hematoxylin eosin staining and X-ray radiography showed that the chondroitins reduced the infiltration of inflammatory cells and prevented joint destruction of the knee and paw. Reverse transcription-polyerase chain reaction analysis revealed that chondroitin administration inhibited the expressions of tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), $interlukin-1{\beta}$ ($IL-1{\beta}$), and $interferon-{\gamma}$ ($IFN-{\gamma}$) in joints more than the administration of vehicle. Chondroitin treatment also decreased the production of rheumatoid factors (RF), IgG and IgM, in the serum of CIA mice. These results indicate that chrondroitin administration has a protective effect involving the inhibition of pro-inflammatory cytokine production in CIA mice.

• Korean Journal of Food Science and Technology
• /
• v.5 no.2
• /
• pp.101-107
• /
• 1973

1) For the purpose of preparation of food and fodder yeasts from nonedible seaweed, two suitable Candida yeasts have been isolated from seaweed compost. 2) They had the ability of fermenting galactose, sucrose and glucose, and could not ferment maltose and mannit, but could assimilate mannit. 3) NaCl concentration from 1 to 2% had no remarkable effect on growth of yeast and the optimum pH was $4{\sim}5$. 4) In the acid hydrolyzate of brown seaweed (Ecklonia cava Kjellman, Sargassum fulvellum AGARDH) an amorphous deposit was produced during storage after neutralization of media and its removal always delayed yeast growth, but addition of $(NH_4)_2SO_4$ and $NaH_2PO_4$ to media could increase the assimilation of reducing sugar and yeast yield. 5) $Co^{60}$ gamma ray irradiation (dose rate : 1 Mrad/hr, BNL shipboard irradiator) of seaweed had not so much effect on the hydrolysis of carbohydrates and nitrogen compounds in seaweed but could increase the yeast production from seaweed hydrolyzate. 6) The yeast yield was $7{\sim}8$ g of dry yeast per 100 g of seaweed by cultivation with jar fermentor.

• Korean Journal of Plant Resources
• /
• v.23 no.1
• /
• pp.19-24
• /
• 2010

This study was conducted to clarify effects on the germination, survival rate of seedlings, growth and variation induction of variants in gamma rays irradiated seed of lilac pink (Dianthus superbus var. longicalycinus) and nursery spiraea (Caryopteris incana). Seed germination and its germination rate were delayed over 90 Gy for lilac pink and 80 Gy for nursery psiraea. Fifty percent lethal time (LT50) level for lilac pink and nursery psiraea were 150 Gy and 100 Gy, respectively. Lilac pink and nursery psiraea were grown dwarf over 120 Gy treatment. We have produced 17 variants of lilac pink in $M_1$ generation, and selected the promising 4 variants in $M_2$ generation. We have also made 7 variants of nursery psiraea in $M_1$ generation, and selected the favorable 8 variants in $M_2$ generation.

• Korean Journal of Agricultural Science
• /
• v.29 no.2
• /
• pp.5-9
• /
• 2002

Culm length of Dohoku mutant 1(DM 1) and mutant 2(DM 2) were shorter than Dohuko parent and Heukjinjubyo check, while days to heading were delayed seven to 20 days Panicle length of these were similar to check and number of panicle per plant of DM 2 was highly appeared than check. Spikelets per plant of the selected lines were lower than check, and glume color of these were varied from brown to dark purple and awn length was also varied according to line used. Anthocyanin content of each mutant line as measured by 530nm were lower than that of check in that OD 2.23 and OD 2.26 for DM 1 and DM 2, respectively, and 2.59 for check.

• Journal of radiological science and technology
• /
• v.11 no.1
• /
• pp.71-77
• /
• 1988

To improve the storage method for kimchi, optimal ripening kimchi was irradiated with doses of 1, 3, 5kGy Co-60gamma radiation, followed by the microbiological, physicochemical and senosory evaluations during storage at $5^{\circ}C$. 1. Total aerobic count increased in the beginning of storage and then decreased slowly as the number of total lactobacilli (anaerobe) increased. The above, total aerobic and lactobacilli were reduced by 1 to 3 log cycles with irradiation and at the 90th day after storage the number of total lactobacilli remained $1.30{\times}10^{8}$ per ml in 3 kGy irradiated group. Irradiation treatment at 3 kGy sterilized coliforms and molds contaminating the sample as the level of $2.0{\times}10^{4}$ per ml and $5.4{\times}10^{2}$ per ml respectively and no apparent growth was observed in both control and 1 kGy irradiated groups after 20 days of storage. The population of yeast, $3.5{\times}10^{3}$ per ml initially, increased steadily during kimchi storage and at 90 days of storage the number was shown to be $5.6{\times}10^{4}$ per ml and $6.5{\times}10^{2}$ per ml in control and 3 kGy irradiated groups, respectively. 2. In the physicochemical changes during kimchi storage, pH, acidity and volatile acid of non-irradiated control at the 45th day after storage were 4.0, 0.7% and 0.066%, while those of 3 kGy irradiated group were 4.2, 0.59 and 0.06% at the 90th day of storage, respectively. The reducing sugar content of all stored samples changed inversely total acidity content, indicating irradiation delayed the changes of them. The amount of ascorbic acid decreased gradually with the storage time and irradiation dose increase. Textural parameters of 3 kGy irradiated group were superior to those of other groups at the latter stage of storage. 3. Sensory evaluations showed that 3 kGy irradiation was the optimum dose level to extend the shelf-life of kimchi more than two months as compared to control.