• Clinical and Experimental Pediatrics
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• v.48 no.12
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• pp.1378-1384
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• 2005

Purpose : We hypothesized dexrazoxane(DXR) and pentoxifylline(PTX) may prevent myocardial damage in adriamycin(ADR)-induced cardiomyopathic rat model. We also investigated their effects on the myocardial apoptosis and fibrosis in ADR induced cardiomyopathy. Methods : The six-week old female Spregue-Dawley rats were divided into control group(CNT, n=4), ADR group(n=6), ADR+DXR group(DXR, n=5), ADR+PTX group(PTX, n=6), ADR+DXR+PTX group(DXPT, n=5). ADR(5 mg/week, twice) was administrated intravenously to rats except CNT group to induce cardiomyopathy. The PTX(50 mg/kg/day) was administered daily from day-0 to Day-21. The DXR(100 mg/kg) was administered 30 minutes before each ADR injection. On day 21, the rats were sacrificed and the degree of histopathologic changes of hypercontraction band necrosis, cytoplasmic vacuolar change and fibrosis were scored. Immunohistochemical staining for Bcl-2 expression and RT-PCR for $TNF-{\alpha}$ and CTGF were performed. Results : Histopathological scores of myocardial damage were significantly higher in ADR rats than CNT rats(P<0.05), and significantly lower in DXPT rats than ADR rats(P<0.01). Myocardial fibrosis was prevented in both PTX rats and DXPT rats. The expression of Bcl-2 was weaker in ADR rats than that in CNT rats(P<0.05), and stronger in both DXR and DXPT rats than that in ADR rats (P<0.05). $TNF-{\alpha}$ concentration of ADR rats was not different from that of treated groups. Conclusion : DXR prevented myocyte apoptosis with increased Bcl-2 expression, and PTX prevented myocardial fibrosis in ADR induced cardiomyopathic rats. The combination therapy of DXR and PTX showed prevention of cardiomyopathy in ADR induced cardiomyopathy rat model.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.6
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• pp.790-795
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• 2012

In this study, the general components and minerals of fermented Curcuma longa L. (FC) by Aspergillus oryzae were examined as well as the hepatoprotective effects of FC on acute hepatotoxicity induced by a single dose of galactosamine (GalN, 650 mg/kg body weight (b.w.)). The FC was found to consist of 0.15% moisture, 4.68% crude fat, 4.35% crude protein, 6.92% crude fiber, and 6.83% crude ash. The P, Ca, and Mg levels in FC were also quantitatively analyzed. Male Sprague-Dawley rats were divided into six groups; nontreated control, GalN, 150 mg/kg b.w. of silymarin plus GalN, 30 mg/kg b.w. of FC plus GalN, 100 mg/kg b.w. of FC plus GalN, and 300 mg/kg b.w. of FC plus GalN. Pretreatment 300 mg/kg b.w. of FC during 14 days significantly decreased the increased in aspartate aminotransferase, alanine amino transferase, and triglyceride (TG) induced by GalN. Severe liver damage, hepatocellular necrosis, infiltration of inflammatory cells, and councilman body necrosis on histopathological liver tissues were observed in GalN treated rats. Administration of 300 mg/kg b.w. of FC significantly decreased the degree of live damage. These results suggest that FC displays hepatoprotective activity and FC was able to lower the TG levels in serum; thus, FC may serve as a useful material for health food and clinical conditions associated with liver disease.

• Journal of the Society of Disaster Information
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• v.11 no.1
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• pp.135-147
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• 2015

Recent underground common utility tunnels are underground facilities for jointly accommodating more than 2 kinds of air-conditioning and heating facilities, vacuum dust collector, information processing cables as well as electricity, telecommunications, waterworks, city gas, sewerage system required when citizens live their daily lives and facilities responsible for the central function of the country but it is difficult to cope with fire accidents quickly and hard to enter into common utility tunnels to extinguish a fire due to toxic gases and smoke generated when various cables are burnt. Thus, in the event of a fire, not only the nerve center of the country is paralyzed such as significant property damage and loss of communication etc. but citizen inconveniences are caused. Therefore, noticing that most fires break out by a short circuit due to electrical works and degradation contact due to combustible cables as the main causes of fires in domestic and foreign common utility tunnels fire cases that have occurred so far, the purpose of this paper is to scientifically analyze the behavior of a fire by producing the model of actual common utility tunnels and reproducing the fire. A fire experiment was conducted in a state that line type fixed temperature detector, fire door, connection deluge set and ventilation equipment are installed in underground common utility tunnels and transmission power distribution cables are coated with fire proof paints in a certain section and heating pipes are fire proof covered. As a result, in the case of Type II, the maximum temperature was measured as $932^{\circ}C$ and line type fixed temperature detector displayed the fire location exactly in the receiver at a constant temperature. And transmission power distribution cables painted with fire proof paints in a certain section, the case of Type III, were found not to be fire resistant and fire proof covered heating pipes to be fire resistant for about 30 minutes. Also, fire simulation was carried out by entering fire load during a real fire test and as a result, the maximum temperature is $943^{\circ}C$, almost identical with $932^{\circ}C$ during a real fire test. Therefore, it is considered that fire behaviour can be predicted by conducting fire simulation only with common utility tunnels fire load and result values of heat release rate, height of the smoke layer, concentration of O2, CO, CO2 etc. obtained by simulation are determined to be applied as the values during a real fire experiment. In the future, it is expected that more reliable information on domestic underground common utility tunnels fire accidents can be provided and it will contribute to construction and maintenance repair effectively and systematically by analyzing and accumulating experimental data on domestic underground common utility tunnels fire accidents built in this study and fire cases continuously every year and complementing laws and regulations and administration manuals etc.

• Neonatal Medicine
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• v.16 no.2
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• pp.221-233
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• 2009

Purpose: Erythropoietin (EPO) has neuroprotective effects in many animal models of brain injury, including hypoxic-ischemic (HI) encephalopathy, trauma, and excitotoxicity. Current studies have demonstrated the neuroprotective effects of EPO, but limited data are available for the neonatal periods. Here in we investigated whether recombinant human EPO (rHuEPO) can protect the developing rat brain from HI injury via modulation of NMDA receptors. Methods: In an in vitro model, embryonic cortical neuronal cell cultures from Sprague-Dawley (SD) rats at 19-days gestation were established. The cultured cells were divided into five groups: normoxia (N), hypoxia (H), and 1, 10, and 100 IU/mL rHuEPO-treated (H+E1, H+ E10, and H+E100) groups. To estimate cell viability and growth, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay was done. In an in vivo model, left carotid artery ligation was performed on 7-day-old SD rat pups. The animals were divided into six groups; normoxia control (NC), normoxia Sham-operated (NS), hypoxia-ischemia only (H), hypoxia-ischemia+vehicle (HV), hypoxia-ischemia+rHuEPO before a HI injury (HE-B), and hypoxia-ischemia+rHuEPO after a HI injury (HE-A). The morphologic changes following brain injuries were noted using hematoxylin and eosin (H/E) staining. Real-time PCR using primers of subunits of NMDA receptors (NR1, NR2A, NR2B, NR2C and NR2D) mRNA were performed. Results: Cell viability in the H group was decreased to less than 60% of that in the N group. In the H+E1 and H+E10 groups, cell viability was increased to >80% of the N group, but cell viability in the H+E100 group did not recover. The percentage of the left hemisphere area compared the to the right hemisphere area were 98.9% in the NC group, 99.1% in the NS group, 57.1% in the H group, 57.0% in the HV group, 87.6% in the HE-B group, and 91.6% in the HE-A group. Real-time PCR analysis of the expressions of subunits of NMDA receptors mRNAs in the in vitro and in vivo neonatal HI brain injuries generally revealed that the expression in the H group was decreased compared to the N group and the expressions in the rHuEPO-treated groups was increased compared to the H group. Conclusion: rHuEPO has neuroprotective property in perinatal HI brain injury via modulation of N-methyl-D-aspartate receptors.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.5
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• pp.459-467
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• 2009

Purpose: The maximum likelihood-expectation maximization (ML-EM) is the statistical reconstruction algorithm derived from probabilistic model of the emission and detection processes. Although the ML-EM has many advantages in accuracy and utility, the use of the ML-EM is limited due to the computational burden of iterating processing on a CPU (central processing unit). In this study, we developed a parallel computing technique on GPU (graphic processing unit) for ML-EM algorithm. Materials and Methods: Using Geforce 9800 GTX+ graphic card and CUDA (compute unified device architecture) the projection and backprojection in ML-EM algorithm were parallelized by NVIDIA's technology. The time delay on computations for projection, errors between measured and estimated data and backprojection in an iteration were measured. Total time included the latency in data transmission between RAM and GPU memory. Results: The total computation time of the CPU- and GPU-based ML-EM with 32 iterations were 3.83 and 0.26 see, respectively. In this case, the computing speed was improved about 15 times on GPU. When the number of iterations increased into 1024, the CPU- and GPU-based computing took totally 18 min and 8 see, respectively. The improvement was about 135 times and was caused by delay on CPU-based computing after certain iterations. On the other hand, the GPU-based computation provided very small variation on time delay per iteration due to use of shared memory. Conclusion: The GPU-based parallel computation for ML-EM improved significantly the computing speed and stability. The developed GPU-based ML-EM algorithm could be easily modified for some other imaging geometries.

• Korean Journal of Environmental Agriculture
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• v.17 no.1
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• pp.70-75
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• 1998

A model of pond system is developed for treatment and recycling of excreta from twenty-five adult dairy cattle. It is composed of wastewater treatment ponds and small fish ponds. Those are three facultative ponds in series; primary-secondary-tertiary pond and these are designed to rear carps without feeding. A pit is constructed at the bottom of primary pond for efficient sludge sedimentation and effective methane fermentation. It is contrived to block into it the penetration of oxygen dissolved in the upper layer of pond water. The excreta from the cattle housed in stalls are diluted by water used for clearing them. The washed excreta flow into the pit. The average yearly $BOD_5$ concentration of influent is 398.7mg/l. That of the effluent from primary, secondary and tertiary pond of the system is 49.18, 27.9, and 19.8.mg/l respectively. Approximate 88, 93, and 95 % of BOD5 are removed in each pond. The mean yearly SS concentration of influent is 360.5 mg/l That of the effluent from each pond is 53.4, 45.7, and32.7mg/l respectively. Approximate 86, 88, and 91% of SS are removed in each pond. The $BOD_5$ concentration of secondary and tertiary pond can satisfy 30mg/l secondary treatment standard. The SS concentration of effluent from tertiary pond, however, is slightly greater than the standard, which results from activities of carps growing in the pond. The average yearly total nitrogen concentration of influent is 206.8mg/l and that of the effluent from each pond is 48.6, 30.8, and 21.0mg/l respectively. Approximate 74, 88, and 90% of total nitrogen are removed in each pond. The mean yearly total phosphorous concentration of influent is 20.7mg/l and that of the effluent from each pond is 5.3, 3.2, and 2.1mg/l respectively. Approximate 97, 98, and 99% of total phosphorous are removed in each pond. The high removal of nitrogen and phosphorous results from active growth of algae in the upper layer of pond water. Important pond design parameters for southern part of Korea -- areal loading of BOD5, liquid depth, hydraulic detention time, free board, and pond arrangement -- are taken up.

• Korean Journal of Ecology and Environment
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• v.41 no.2
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• pp.188-197
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• 2008

This research was a preliminary case study to determine the levels of total mercury in the tissues of sentinel species (Zacco platypus) and ecological health in relation to habitat characteristics and chemical conditions. We collected fishes in Gap Stream during June$\sim$October 2007 and analyzed the total mercury from five types of tissues such as liver, kidney, gill, vertebrae and muscle of Zaceo platypus using Direct Mercury Analyzer (DMA-80, US EPA Method 7473). Mean concentrations of total [Hg], based on all tissues, was 67.2 and $20.7\;{\mu}g\;kg^{-1}$, in the upstream and downstream site, respectively, indicating 3 times greater level in the upstream. In other words, the levels were higher in the pristine upstream than the downstream influenced by the wastewater disposal plant. Chemical water quality, based on BOD, COD and nutrients (TN, TP) showed that severe degradation occurred in the downstreams than the upstreams. Index of Biological Integrity (IBI) using fish multi-metric model averaged 32, indicating a "good$\sim$fair" condition and varied from 42 (excellent$\sim$good) at S2 to 22 (fair$\sim$poor) at S5 depending on the sites sampled. Qualitative Habitat Evaluation Index (QHEI) in the all sites averaged 142, which was judged as "good" habitat health, but showed a high variation (181 in Site 2 vs. 67 in Site 5). Overall data suggest that health conditions, based on IBI and QHEI, was better in the upstream sites but the mercury bioaccumulation levels in the fish tissues were opposite. We believe that measurements of various parameters are required for a diagnosis of integrative ecosystem health.

• Journal of Gifted/Talented Education
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• v.22 no.3
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• pp.575-596
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• 2012

Students' perception on a science program for gifted was investigated. The whole program was designed in consistency and integrity based on the Autonomous Learner Model suggested by Betts & Kercher(1999). 7th, 8th and 9th grade students were enrolled in this program, offered by G Education Institute for Gifted(GEI) located in Seoul. A survey was done to ask students' perception regarding the effect of the program. The survey consisted of statements about the expected effects of the program and students were asked if they agreed with the statements. Most students strongly agreed that GEI's program has positive effects. Students replied that they learned useful and interesting science contents, enjoyed meaningful experience of cooperating with members in small groups, and were challenged by the inquiry tasks. They recognized that they were being trained to become autonomous learners. They also said that their choices and decisions were respected, which resulted in positive effects on their ability to negotiate or to inquire actively. These implies that Autonomous Learner Model had been successfully applied. Although it was not clear autonomy of students was fully grown, the possibility of becoming an autonomous learner was evident. Satisfaction level is higher for the older students, implying that the integrity in the program gave accumulating effect. Students response showed that three sub-programs of GEI, the classes of each subject, conference at the end of the year and autonomous learner training played equally important role for students to learn the process of scientific inquiry and autonomous learning. This was a positive sign that the strategies for scientific inquiry and autonomous learning were embedded and integrated deeply in the program. The results of current research suggests that the integrity of a program based on a specific education model for the gifted could provide better education environment for the gifted students.

• Journal of the Korean Geographical Society
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• v.31 no.2
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• pp.106-127
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• 1996

In Korea, modern geomorphology has developed as one of main subjects in geography, such as in Europe. Geomorphology is one of the most advanced specialties in the geography dicipline, since foundation of Korean Geographical Society in 1945. Untill 1960's study, first generation of the Korean geomorphologists trained the younger ones, together with energetic research activities. Their great works in education and research established the base of ulterier development of the geomorphology in Korea. Since 1970s, research manpower and quality has incresed rapidly, partly due to the various international activities and cooperations of Korean geomorphologists. Owing to above development, Korean geomorphologist was able to found "The Geomorphological Association of Korea" in 1990 and publish "Journal of GAK", since 1994. Furthermore, geomorphologists are playing important roles in interdisciplinary academic societies, such as "The Korean Quaternary Assocition". Still 1960s, our research had focused on the identification and interpretation of erosional surfaces in Korea Peninsular. Of course, W.M. Davis's "Geographical Cycle Theory" and L.C. King's "Pedimentation Theory" had a great influence on the Koerans' works. After 1970s, the study of erosional surface played the important role in setting up the morphoclimatic viewpoint and methodology. Research scope tend to be notably broad and various than it was untill 1960's. Disposotion of the scientific methods and techniques become more and more apparent. These trends of research has settled precise descreption and interpretation of actual landforms, based on the careful field works, scientific measuring, and analisis, rather than methodology focused on the particular master theories. Recent geomorphological researches show the scope from climatic geomorphology and Quaternary geomorphology to granite and limestone weathering, pedo-geomorphogenic environment and periglacial landforms, focused on the small-to-medium scales. And then there have been new trying to interprete erosional surfaces such as hillslopes and terraces. Also, studies of coastal and plain landforms have been successfully developed. Recent new trends show the quantitative and analytic modelling using field measurement and laboratory work, and study on the human impacts on the natural landforms.y on the human impacts on the natural landforms.

• Sleep Medicine and Psychophysiology
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• v.8 no.1
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• pp.52-58
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• 2001

Objectives: An Increased level of psychophysiologic arousal and diminished physiologic flexibility would be observed in patients with panic disorder compared with a normal control group. We investigated the differences of psychophysiologic response between patients with panic disorder and normal control to examine this hypothesis. Methods: Ten Korean patients with panic disorder who met the diagnostic criteria of DSM-IV were compared with 10 normal healthy subjects. In psychological assessment, levels of anxiety and depression were evaluated by State-Trait Anxiety Inventory, Beck's Depression Inventory and Hamilton Rating Scale For Anxiety and Depression. Heart rate, respiration rate, electrodermal response, and electromyographic activity were measured by biofeedback system (J & J I-330 model) to determine psychophysiologic responses on autonomic nervous system. Stressful tasks included mental arithmetic, video game, hyperventilation, and talking about a stressful event. Psychophysiologic responses were measured according to the following procedures : baseline(3 min)-mental arithmetic (3 min)-rest (3 min)-video game (3 min)-rest (3 min)-hyperventilation (3 min)-rest (3 min)-talking about a stressful event (3 min). Results: The baseline level of anxiety and depression, electrodermal response (p=.017), electromyographic activity (p=.047) and heart rate (p=.049) of patients with panic disorder were significantly higher than those of the normal subject group. In electrodermal response, patient group had significantly higher startle response than the control group during hyperventilation (p=.001). Startle and recovery responses of heart rate in the patient group were significantly lower than responses in the control group during mental arithmetic (p=.007, p=.002). In electrodermal response of the patient group, startle response was significantly higher than recovery response during mental arithmetic (p=.000) and video game task (p=.021). Recovery response was significantly higher than startle response in respiratory response during hyperventilation. Conclusion: The results showed that patients with panic disorder had higher autonomic arousal than the control group, but the physiologic flexibility was variable. We suggest that it is helpful for treatment of panic disorder to decrease the level of autonomic arousal and to recover the physiologic flexibility in certain stressful event.