• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.68.1-68.1
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• 2012

We present a comprehensive study of the stellar populations in two faint M31 dwarf satellites, And XI and And XIII. Using deep archival images from the Wide Field Planetary Camera 2 (WFPC2) onboard the Hubble Space Telepscope (HST), we characterize the horizontal branch (HB) morphologies and the RR Lyrae (RRL) populations of these two faint dwarf satellites. Our new template light curve fitting routine (RRFIT) detected RRL populations from both galaxies. The mean periods of $RR_{ab}$ (RR0) stars in And XI and And XIII are < $P_{ab}$ > = $0.621{\pm}0.040$, and < $P_{ab}$ > = $0.648{\pm}0.038$ respectively. Even though the RRL populations show a lack of $RR_{ab}$ stars with high amplitudes (Amp(V) > 1.0 mag) and relatively short periods ($P_{ab}$ ~ 0.5 days), their period - V band amplitude (P-Amp(V)) relations track the lower part of the general P-Amp(V) trend in the M31 outer halo RRL populations. The metallicities of $RR_{ab}$ stars were calculated via the [Fe/H]-log $P_{ab}$-Amp(V) relationship of Alcock et al. The metallicities thus obtained ($[Fe/H]_{And}$ $_{XI}=-1.75%$; $[Fe/H]_{And}$ $_{XIII}=-1.74$) are consistent with the values calculated from the RGB slope indicating that our measurements are not significantly affected by the evolutionary effects of RRL stars. We discuss the origins of And XI and And XIII based on a comparative analysis of the luminosity-metallicity (L-M) relation of Local Group dwarf galaxies.

• Journal of Preventive Medicine and Public Health
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• v.19 no.2 s.20
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• pp.184-192
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• 1986

Since the wide spread application of hyperbaric oxygenation in clinical setting, the problems of oxygen toxicity have been attracting a deep interest from the researchers on hyperbaric medicine as a practical issue. Among extensive research trials, the study on the protective agents against oxygen toxicity occupied one of the most challenging field. As the mechanisms of oxygen toxicity, the role of the oxygen free radicals produced by peroxidation process are strongly accepted by the leading researchers on oxygen toxicity, the probable protective effects of antioxidant against oxygen toxicity are sustaining a sufficient rationale. In this study, the author attempted to evaluate the effect of vitamin E as a protective agent against oxygen toxicity through the observation of death rate, convulsion rate, time to convulsion, and macroscopic and microscopic pathological changes of experimental rats exposed to 100% oxygen at 5 ATA for 120 minutes. The findings observed are as follows: 1) The death rate, convulsion rate, time to convulsion, organ/body weight ratio and microscopic pathological findings were identified as reliable objective and quantitative indices for oxygen toxicity. 2) Vitamin E showed excellent protective effects against CNS and pulmonary oxygen toxicity as a strong antioxidant. The most effective dose seemed to be around 400 mg/kg 3) The results of this study are supporting the oxygen free radical hypothesis on oxygen toxicity.

• Journal of Korean Physical Therapy Science
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• v.26 no.2
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• pp.51-60
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• 2019

Background: The purpose of this study was to investigate the effects of HBOT (hyperbaric oxygen therapy) on the pain, ROM (range of motion) and muscle fatigue recovery of DOMS (delayed onset muscle soreness). Design: Randomized Controlled Trial. Methods: Twenty-six subjects who are student in their 20s at a university participated in this study, these subjects were assigned into two groups, a control group (n=12) and an experiment group (n=14). The subjects in experimental group were intervened by HBOT (40 minutes, 1.3 ATA), while ones on control group weren't by any intervention after induced DOMS. Results: First, in the comparison of VAS (visual analog scale), there were significant variations with the period (p<0.001), interaction of period (p<0.05) and group (p<0.05). In the comparison of PPT (pressure pain threshold), there were significant variations with the period (p<0.001) and interaction of period (p<0.05). Second, in the comparison of ROM, there were significant variations with the period (p<0.001), interaction of period (p<0.001) and group (p<0.01). Third, in the comparison of CK (creatine kinase) and LDH (lactate dehydrogenase), there no signigicant variations with all measure variables. Conclusion: The above results indicated that HBOT were effective to decrease the pain and improve the ROM in DOMS. Also the statistical significant variations of blood factors of muscle fatigue were not found in this.

• Structural Engineering and Mechanics
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• v.86 no.6
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• pp.739-750
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• 2023

This study examines the two-level behavior of the toggle brace damper within a steel frame having a yielding pipe damper and rotational friction damper. The proposed system has two kinds of fuse for energy dissipation in two stages. In this mechanism, rotational friction damper rather than hinged connection is used in toggle brace system, connected to a pipe damper with a limited gap. In order to create a gap, bolted connection with the slotted hole is used, such that first a specific movement of the rotational friction damper solely is engaged but with an increase in movement, the yielding damper is also involved. The performance of the system is such that at the beginning of loading the rotational friction damper, as the first fuse, absorbs energy and with increasing the input load and further movement of the frame, yielding damper as the second fuse, along with rotational friction damper would dissipate the input energy. The models created by ABAQUS are subjected to cyclic and seismic loading. Considering the results obtained, the flexibility of the hybrid two-level system is more comparable to the conventional toggle brace damper. Moreover, this system sustains longer lateral displacements. The energy dissipation of these two systems is modeled in multi-story frames in SAP2000 software and their performance is analyzed using time-history analysis. According to the results, permanent relocations of the roof in the two-level system, in comparison with toggle brace damper system in 2, 5, and 8-story building frames, in average, decrease by 15, 55, and 37% respectively. This amount in a 5-story building frame under the earthquakes with one-third scale decreases by 64%.

• Safety and Health at Work
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• v.14 no.3
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• pp.332-339
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• 2023

Background: The aim of the study was to test the validity and reliability of the Perceived Future Decent Work Securement Scale for Turkish nursing students. Methods: A cross-sectional, methodological study design was used. The study was carried out at three nursing undergraduate programs in Turkey during the academic year of 2020-2021 with 336 senior nursing students. Language validity and content validity analyses were performed for the scale adaptation, followed by confirmatory factor analysis (CFA) for construct validity. The reliability of the scale was determined using the test-retest and Cronbach's alpha internal consistency coefficient. Results: The scale-content validity index score was 0.988. In CFA, all goodness-of-fit indices verified the acceptable fit of the model; its root mean square error of approximation was 0.076; the normed fit index was 0.909; the standardized mean square residual was 0.097; the relative fit index was 0.881; the goodness-of-fit index was 0.915; the adjusted goodness-of-fit index was 0.872 and χ²/df = 2.932. The overall reliability was α = 0.86. The item-total correlations of the scale were above the acceptable level, and the test-retest analysis had a high correlation. The access to healthcare (14.68, SD 3.53) obtained the highest average score, and the adequate compensation (8.52, SD 3.76) was the lowest rated by the senior nursing students. Conclusion: The Perceived Future Decent Work Securement Scale is a valid and reliable scale to assess nursing students' future decent work securement.

• Korean Journal of Microbiology
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• v.49 no.3
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• pp.228-236
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• 2013

Campylobacter jejuni is one of important food-borne pathogens causing human gastroenteritis. We isolated 42 strains of C. jejuni from diarrhea patients and 4 food-poisoning outbreaks in 2010, Gyeonggi-do. In this study, 42 strains were tested for genetic characteristics, the serotype distribution and antimicrobial resistant rate. The presence of hipO (100%), cdtB (100%), and mutated gyrA (95.2%) genes was detected in C. jejuni by polymerase chain reaction (PCR). Detection of mutated gyrA gene correlated with ciprofloxacin resistance. Forty isolates had mutated gyrA gene and were actually resistant to ciprofloxacin. Furthermore, comparing the gyrA DNA sequence data, ciprofloxacin-resistant isolates had a mutation of the DNA sequence from ACA (threonine) to ATA (isoleucine). But 41 strains (97.6%) of patient isolates were susceptible to erythromycin and azithromycin. A total of 35.7% among 42 C. jejuni isolates were identified into 4 different serotypes. The serotype distribution of C. jejuni strains were shown to be HS2(B), HS3(C), HS4(D), HS19(O). To investigate the genotypes of C. jejuni isolated in Gyeonggi province, repetitive sequence polymerase chain reaction (rep-PCR) analysis and SmaI-digested pulsed-filed gel electrophoresis (PFGE) profile analysis were performed. From the PFGE analysis of 42 C. jejuni strains, 12 clusters of PFGE profile were obtained. On the other hand, 11 clusters of rep-PCR profile were obtained from 42 strains of C. jejuni.

• The Korean Journal of Nuclear Medicine
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• v.37 no.2
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• pp.110-119
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• 2003

Purpose: Radioiodine (I-131) therapy is an effective modality to reduce both recurrence and mortality rates in differentiated thyroid cancer. Whether higher doses shows higher therapeutic responses was still debatable. The purpose of this study was to validate curve-fitting (CF) method measuring maximum permissible dose (MPD) by a biological dosimetry using metaphase analysis of peripheral blood lymphocytes. Materials and Methods: Therapeutic effects of MPD was evaluated in 58 patients (49 females and 9 males, mean age $50{\pm}11$ years) of papillary thyroid cancer. Among them 43 patients were treated with ${\Leq}7.4GBq$, while 15 patients with ${\geq}9.25GBq$. The former was defined as low-dose group, and the latter high-dose group. Therapeutic response was defined as complete response when complete disappearance of lesions on follow-up I-131 scan and undetectable serum thyroglobulin levels were found. Statistical comparison between groups were done using chi-square test. P value less than 0.05 was regarded as statistically significant. Results: MPD measured by CF method using tracer and therapeutic doses were $13.3{\pm}1.9\;and\;13.8{\pm}2.1GBq$, respectively (p=0.20). They showed a significant correlation (r=0.8, p<0.0001). Exposed doses to blood measured by CF and biological methods were $1.54{\pm}0.03\;and\;1.78{\pm}0.03Gy$ (p=0.01). They also showed a significant correlation (r=0.86, p=0.01). High-dose group showed a significantly higher rate of complete response (12/15, 80%) as compared to the low-dose group (22/43, 51.2%) (p=0.05). While occurrence of side effects was not different between two groups (40% vs. 30.2%, p=0.46). Conclusion: Measurement of MPD using CF method is reliable, and the high-dose I-131 therapy using MPD gains significantly higher therapeutic effects as compared with low-dose therapy.

• Journal of Preventive Medicine and Public Health
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• v.13 no.1
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• pp.13-18
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• 1980

The ultimate goal of treatment of carton monoxide poisoning is to promote dissociation of carboxyhemoglobin and to maintain arterial $PO_2$ above 50mmHg throughout the course of treatment to protect vital organs from damage caused by hypoxia. The hyperbaric chamber designed and manufactured for this purpose has obviousely made an enormous contribution and yet has several handicaps to be overcome by any means. These handicaps are: the financial impact to purchase the chamber (especially in a small, remote community), an extra manpower requirement to operate the device, limitation in the capacity of the chamber (one man type), and the possible hazard of oxygen intoxication and dysbarism. The primary objective of this study is to develope a new therapeutic measure as an alternative to the hyperbaric chamber when it is not available or contraindicated. The effect of intestinal perfusion with hydrogen peroxide has been studied by many investigators and was known to be an excellent way of extrapulmonary oxygen supply. the advantage of this method will include; 1) much more amount of oxygen is delivered to the tissue than one would expect from 100% saturation with oxygen at 1 ata, 2) the procedure is simple and most economical, 3) neither sophisticated equipment nor extra manpower is required. As a study preliminary to the clinical application, authors conducted a series of experiment to observe the effect of hydrogen peroxide enema on dissociation of carboxyhemoglobin in intoxicated rabbit blood. Using an animal gas chamber, 20 rabbits were exposed to CO gas of 6,000 ppm for 60 minutes. Ten rabbits of control group were given 10cc of warmed normal saline solution by reactal perfusion and for the other 10 of the experimental group, the same amount of 1% $H_{2}O_{2}$ solution was given by the same way. Two blood specimens were drawn from each rabbit: the first one immediately following the exposure and the second one after rectal perfusion, about 30 minutes after the first sampling. The result was as follows; 1) The decrease in carboxyhemoglobin concentration during the first 30 minutes in the control and experimental group were $18.18{\pm}4.49%\;and\;23.03{\pm}4.13%$ respectively shelving the significant difference (p<0.05) between the two groups. 2) Hemoglobin and hematocrit value showed no significant difference between two groups and not altered significantly by intestinal perfusion with $H_{2}O_{2}$.

• Korean Journal of Veterinary Research
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• v.40 no.3
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• pp.497-504
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• 2000

To document that effects of hyperbaric oxygen(HBO) and ${\alpha}-tocopherol$ on full-thickness skin grafts in rat, we performed full-thickness skin grafts bilaterally on each rats. The HBO-treated rats were received HBO twice daily for 90 minutes at 2 ATA. Surgical control rats were not treated with HBO. ${\alpha}-tocopherol$ treated rats were received the agent via oral gastric tube daily for 3 days preoperative and a fourth dose 1 to 2 hours postoperative. HBO plus ${\alpha}-tocopherol$ treated rats were received HBO and ${\alpha}-tocopherol$ as mentioned above. Biopsy specimens were taken from each rat at the time of grafting and on days 2, 4, 7, 10, 14, 21, and 28, then were processed for tissue-concentration of total glutathione(GSHt), oxidized/reduced glutathione level, and thiobarbituric acid-reactive substance(TBARS) levels. The percentage of viable graft on day 10 ranged from 67 to 93%, and was not significantly different among the each other groups. The percentage of viable graft were, however, higher in HBO plus ${\alpha}-tocopherol$ treated rats(78.6%) than in HBO alone treated rats(59.1%), ${\alpha}-tocopherol$ alone treated rats(66.7%) and surgical control rats(58.2%). TBARS concentration had a significant increase from preoperative concentration at day 2, and peak concentration at day 4(p<0.01). Concentration then decreased to preoperative concentration at day 28. GSHt concentration of free skin graft had a similar patteren of change in four groups and decreased significantly from preoperative concentration at day 2, returning to preoperative concentration by day 7(surgical control, HBO-treated, and ${\alpha}-tocopherol-treated$, alone) and 28(HBO plus ${\alpha}-tocopherol-treated$). Percentage of the concentration of reduced glutathione decreased in surgical control, HBO-treated and, ${\alpha}-tocopherol-treated$(p<0.05), and HBO plus ${\alpha}-tocopherol-treared$(p<0.01) on day 7 after surgery, whereas the concentration of oxidized increased significantly in HBO-treated(p<0.05), ${\alpha}-tocopherol-treated$(p<0.05), and HBO plus ${\alpha}-tocopherol-treated$(p<0.01).

• Journal of Bio-Environment Control
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• v.17 no.1
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• pp.32-37
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• 2008

Light transmittance of PO-2 film was 71.2% higher than any other films, because of low amount of pending water and attaching dust on film surface. On dawn, the air temperature of tunnel were higher than that of outdoors as much as between 11.8 and $14.5^{\circ}C$ on Feb. 19 to 20, 2007. The air temperature in the greenhouse covered with PO-2 film was higher than any other films as much as $2.3^{\circ}C$. Analyzing of folate in oriental melon, the folate contents of fruit were between 68.9 and $113.4\;{\mu}g/100\;g$ according to varieties. In winter, the folate contents in the treatment of PO-2 film was higher than that in the treatment of PE film as much as 17%. Above $15^{\circ}C$ in outdoors mean air temperature, the folate contents were as much as between 55.2 and $75.2\;{\mu}g/100\;g$. The folate contents in the treatment of PO-2 film was higher than that in the treatment of PE film as much as 36%.