• 전기의세계
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• v.23 no.5
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• pp.54-60
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• 1974

Proposals were mode on how to differentiate radiation effects in morphological phases of polyethylene and discussions were developed with the results obtained on a low density polyethylene, SOCAREX, specified by number average molecular weight; overbar Mn=5,400, density; 0.92, and degree of branch; 3.4/100 carbon atom, which was irradiated to Co$^{60}$ .gamma. ray at the dose rate of 0.5 Mrad/hr in ambient temperature under the pressure of 10$^{-5}$ Torr. or 1 atm. respectively. The effect to crystalline phase in possibly deduced from dose dependent variation of relative area between (110) and (200) peaks on X ray diffraction spectrum and that, the effects to amorphous phase can be understood through dose dependent relaxation behaviours of .betha. peak on internal friction characteristics of the specimen. The results obtained thus far indicate that, in crystalline phase, relative crystallinity shows a rather rapid decrease up to 20 Mrad with increasing dose, however, little change of crystallinity can be observed in the region between 20-200 Mrad, and degradation appears to be more predominant than crosslinking up to 60 Mrad. While in amorphous phase the indication also shows that degradation is only predominant up to 20 Mrad. Furthermore several correlations can be seen with amenable explanation between dose dependent behaviours observed in both phases.

• Journal of radiological science and technology
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• v.45 no.2
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• pp.165-170
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• 2022

Staphylococcus aureus is a major pathogen that causes clinical infections in humans and can also cause massively colonized in lesion skin, particularly in atopic dermatitis patients. This study investigated the effects of photodynamic inactivation with radachlorin and diode laser irradiation on the viability of S. aureus in vitro and assessed the effects of the dose of laser transmission. In the PDI group, 5 𝜇L of S. aureus suspension and 5 𝜇L of radachlorin were inoculated in a 55 mm petri dish (63.6 cm²). The samples were placed in a 37° incubator for 30 min and then irradiated with light (660 nm diode laser). After laser irradiation, the cells were stored for 24 h at 37° in an incubator with 5% CO2, and the number of colonies was counted. All CFU/mL of S. aureus were reduced by diode laser in the presence of radachlorin, with a killing rate of 87.9% at an energy dose of 9 J/cm². This study contribute to treat colonized with S. aureus in atopic dermatitis patients and wound infections by providing information on the optimal dose of laser transmission using PDI to eliminate S. aureus.

• ETRI Journal
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• v.27 no.4
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• pp.449-452
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• 2005

The electrical characteristics of solid state devices such as the bipolar junction transistor (BJT), metal-oxide semiconductor field-effect transistor (MOSFET), and other active devices are altered by impinging photon radiation and temperature in the space environment. In this paper, the threshold voltage, the breakdown voltage, and the on-resistance for two kinds of MOSFETs (200 V and 100 V of $V_{DSS}$) are tested for ${\gamma}-irradiation$ and compared with the electrical specifications under the pre- and post-irradiation low dose rates of 4.97 and 9.55 rad/s as well as at a maximum total dose of 30 krad. In our experiment, the ${\gamma}-radiation$ facility using a low dose, available at Korea Atomic Energy Research Institute (KAERI), has been applied on two commercially available International Rectifier (IR) products, IRFP250 and IRF540.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.21 no.2
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• pp.183-191
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• 2023

The potential impact of hypothetical accidents that occur during the immediate and deferred dismantling of the Kori Unit 1 steam generator has been comprehensively evaluated. The evaluation includes determining the inventory of radionuclides in the Steam Generator based on surface contamination measurements, assuming a rate of release for each accident scenario, and applying external and internal exposure dose coefficients to assess the effects of radionuclides on human health. The evaluation also includes calculating the atmospheric dispersion factor using the PAVAN code and analyzing three years of meteorological data from Kori NPP to determine the degree of diffusion of radionuclides in the atmosphere. Overall, the effective dose for residents living in the Exclusion Area Boundary (EAB) of Kori NPP is predicted, an it is found that the maximum level of the dose is 0.034% compared to the annual dose limit of 1 mSv for the general public. This implies that the potential impact of hypothetical accidents on human health discussed above is within acceptable limits.

• Archives of Plastic Surgery
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• v.41 no.1
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• pp.40-44
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• 2014

Background Chloral hydrate (CH) is the primary agent most commonly used for pediatric sedation prior to diagnostic, therapeutic procedures. In the management of pediatric facial laceration, the initial dose of CH has to balance the need for adequate sedation against the need to minimize sedative complications. Methods A retrospective review of medical records of 834 children who visited our emergency room for facial lacerations from August 2010 to September 2012 was conducted. They were divided into six groups on the basis of the initial dose of CH administered. Further, each group was compared with the standard group (70 to ${\leq}80mg/kg$) with respect to sedation success, augmentation dose, failed sedation, time to procedure, and time of stay. Results With respect to the complication rate, only group 1 (range, 40 to ${\leq}50mg/kg$) showed a significantly lower complication rate. In the case of all the other variables considered, there were no significant differences among any of the groups. Conclusions An initial CH dose of $48{\pm}2mg/kg$ does not negatively affect the success rate of sedation or the need for additional sedative during the primary closure of facial lacerations in pediatric patients. Further, lower doses reduce the incidences of adverse effects and do not delay procedure readiness. Therefore, $48{\pm}2mg/kg$ of CH can be considered the optimal initial dose for pediatric sedation.

• Clinical and Experimental Reproductive Medicine
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• v.40 no.2
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• pp.83-89
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• 2013

Objective: To investigate outcomes of stimulated IVF cycles in which GnRH antagonist was omitted on the ovulation triggering day. Methods: A total of 86 women who underwent controlled ovarian hyperstimulation with recombinant FSH and GnRH antagonist flexible multiple-dose protocols were recruited and prospectively randomized into the conventional group (group A) or cessation group (group B). The GnRH antagonist, 0.25 mg/day of cetrorelix, was started when the leading follicle reached 14 mm in diameter and was continuously administered until the hCG triggering day (group A, 43 cycles) or until the day before hCG administration (group B, 43 cycles). The maturity of oocytes, fertilization rate, embryo quality, and implantation and clinical pregnancy rates were evaluated. Results: The duration of ovarian stimulation, total dose of gonadotropins, serum estradiol levels on hCG administration day, and number of oocytes retrieved were not significantly different between the two groups. The total dose of GnRH antagonist was significantly lower in group B than group A ($2.5{\pm}0.9$ vs. $3.2{\pm}0.8$ ampoules, p<0.05). There was no premature luteinization in any of the subjects. The proportion of mature oocytes and fertilization rate were not significantly different in group B than group A (70.7% vs. 66.7%; 71.1% vs. 66.4%, respectively). There were no significant differences in the implantation or clinical pregnancy rates. Conclusion: Our prospective randomized study suggested that cessation of GnRH antagonist on the hCG administration day during a flexible multiple-dose protocol could reduce the total dose of GnRH antagonist without compromising its effects on pregnancy rates.

• Journal of Plant Biology
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• v.3 no.2
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• pp.1-5
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• 1960

Azotobacter is isolated from soil and its purified species is identified as A. chroococcum. The survival rate of Azotobacter irradiated with UV light is measured, and the reproductive rates of the survivals are calculated. In general, not only the survival rate, but also the length of the generation time of the survival progeny is inversely proportional to the irradiated dose of UV light. The reproduvtive rate of Azotobacter is increased with the exogeneous treatment of nucleic acid derivatives.

• Journal of Veterinary Clinics
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• v.16 no.1
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• pp.65-68
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• 1999

This study was carried to get detailed information about the analeptic effect of yohimbine on succinylcholine muscle relaxant. Succinylcholine was administered intra- venously at a dose rate of 0.05 mg per kg of body weight and then ten minutes after the succinylcholine injection, yohimbine was administered intravenously at a dose rate of 0.1 mg per kg of body weight. The results obtained were as follows. 1. Induction time of muscle relaxation was fast and favourable as 38 seconds. 2. Mean arousal time and mean walk time were significantly shortened by yohimbine administration in the dogs immobilized with succinylcholine (p＜0.01). 3. Heart rate was slightly increased after succinylcholine administration, and increased significantly after yohimbine administration compared to the control group (p＜0.05). 4. Glucose concentration was slightly increased after succinylcholine administration, and decreased after yohimbine administration compared to the control group.

• Journal of Radiation Industry
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• v.8 no.2
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• pp.89-95
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• 2014

This study was conducted to determine the optimal dose of gamma-ray on the growth and nucleus DNA damage for mutation breeding in licorice. Gamma-rays irradiated to dry seeds with various doses (0 to 1000 Gy). Significant decreases in germination rate (%), survival rate (%) and growth characteristics (plant height, number of leaves, root length and fresh weight) were observed by dose of increased. $LD_{50}$ (lethal dose) was approximately 400 Gy to 500 Gy. Also, reduction doses ($RD_{50}$) of plant height, number of leaves, root length and flash weight were 428 Gy, 760 Gy, 363 Gy and 334 Gy, respectively. It is supplest that the optimal dose of gamma irradiation for licorice mutation induction might be about 400 Gy in this study. We also conducted comet assay to observe nucleus DNA damage due to gamma irradiation. In comet assay, a clear difference was identified over 300 Gy treatments. With increasing doses of gamma-ray in the range of 100 to 1000 Gy, the rate of head DNA was decreased significantly from 92.88% to 73.09%. Tail length(${\mu}m$) was increased as the dose of increased over 300 Gy. Growth characteristics (Germination rate, Survival rate, plant height, number of leaves, root length and fresh weight) were highly negatively ($P{\leq}0.01$) correlated with dose. While the tail length was highly positively ($P{\leq}0.01$) correlated with dose.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2002.11a
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• pp.116-117
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• 2002

This study was conducted to investigate the effects of dilution rate and stored time of semen at 5, 25 and 35$^{\circ}C$ on mobility in liquid rooster semen. At 5$^{\circ}C$ cold temperature, no significant difference were found in sperm mobilities on dilution rate and stored time among treatments stored at 5$^{\circ}C$. Sperm mobility for the conservation of 1 hours at 25$^{\circ}C$ and 3 hours at 35$^{\circ}C$ were significantly higher for 1：2 and 1：3 dilution rate(semen： diluent) groups than for 1：1 dilution rate group(P〈0.05), In Fertility results after artificial insemination with different number of sperm per dole, fertilization rate of liquid rooster semen diluted with skim milk-glucose solution were 90.67, 94.00, 96.00, and 98.67% for 0.2${\times}$10$\^$8//dose, 0.4${\times}$10$\^$8//dose, 1.0${\times}$10$\^$8//dose, and 2.0${\times}$10$\^$8//dose groups, respectively. To have more than 90% fertility, 0.2${\times}$10$\^$8/ sperm per dose for the artificial insemination (AI) could be used, And to have more 94% fertility, 0.4${\times}$10$\^$8/ sperm per dose AI could be used practically.