• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.111-112
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• 2009

Diamond-like carbon (DLC) is a convenient term to indicate the compositions of the various forms of amorphous carbon (a-C), tetrahedral amorphous carbon (ta-C), hydrogenated amorphous carbon and tetrahedral amorphous carbon (a-C:H and ta-C:H). The a-C film with disordered graphitic ordering, such as soot, chars, glassy carbon, and evaporated a-C, is shown in the lower left hand corner. If the fraction of sp3 bonding reaches a high degree, such an a-C is denoted as tetrahedral amorphous carbon (ta-C), in order to distinguish it from sp2 a-C [2]. Two hydrocarbon polymers, that is, polyethylene (CH2)n and polyacetylene (CH)n, define the limits of the triangle in the right hand corner beyond which interconnecting C-C networks do not form, and only strait-chain molecules are formed. The DLC films, i.e. a-C, ta-C, a-C:H and ta-C:H, have some extreme properties similar to diamond, such as hardness, elastic modulus and chemical inertness. These films are great advantages for many applications. One of the most important applications of the carbon-based films is the coating for magnetic hard disk recording. The second successful application is wear protective and antireflective films for IR windows. The third application is wear protection of bearings and sliding friction parts. The fourth is precision gages for the automotive industry. Recently, exciting ongoing study [1] tries to deposit a carbon-based protective film on engine parts (e.g. engine cylinders and pistons) taking into account not only low friction and wear, but also self lubricating properties. Reduction of the oil consumption is expected. Currently, for an additional application field, the carbon-based films are extensively studied as excellent candidates for biocompatible films on biomedical implants. The carbon-based films consist of carbon, hydrogen and nitrogen, which are biologically harmless as well as the main elements of human body. Some in vitro and limited in vivo studies on the biological effects of carbon-based films have been studied [$2{\sim}5$].The carbon-based films have great potentials in many fields. However, a few technological issues for carbon-based film are still needed to be studied to improve the applicability. Aisenberg and Chabot [3] firstly prepared an amorphous carbon film on substrates remained at room temperature using a beam of carbon ions produced using argon plasma. Spencer et al. [4] had subsequently developed this field. Many deposition techniques for DLC films have been developed to increase the fraction of sp3 bonding in the films. The a-C films have been prepared by a variety of deposition methods such as ion plating, DC or RF sputtering, RF or DC plasma enhanced chemical vapor deposition (PECVD), electron cyclotron resonance chemical vapor deposition (ECR-CVD), ion implantation, ablation, pulsed laser deposition and cathodic arc deposition, from a variety of carbon target or gaseous sources materials [5]. Sputtering is the most common deposition method for a-C film. Deposited films by these plasma methods, such as plasma enhanced chemical vapor deposition (PECVD) [6], are ranged into the interior of the triangle. Application fields of DLC films investigated from papers. Many papers purposed to apply for tribology due to the carbon-based films of low friction and wear resistance. Figure 1 shows the percentage of DLC research interest for application field. The biggest portion is tribology field. It is occupied 57%. Second, biomedical field hold 14%. Nowadays, biomedical field is took notice in many countries and significantly increased the research papers. DLC films actually applied to many industries in 2005 as shown figure 2. The most applied fields are mold and machinery industries. It took over 50%. The automobile industry is more and more increase application parts. In the near future, automobile industry is expected a big market for DLC coating. Figure 1 Research interests of carbon-based filmsFigure 2 Demand ratio of DLC coating for industry in 2005. In this presentation, I will introduce a trend of carbon-based coating research and applications.

• Clinical and Experimental Pediatrics
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• v.46 no.10
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• pp.989-995
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• 2003

Purpose : Dexamethasone is frequently administered to prevent or treat chronic lung disease in human neonates who are also prone to hypoxic-ischemic(HI) insults. Recently, meta-analysis of the follow-up studies reveals a significantly increased odd ratio for the occurrence of cerebral palsy or an abnormal neurologic outcome, and there is conflicting evidence regarding the impact of dexamethasone exposure on HI brain injury. This study was conducted to explore the effect of post-HI dexamethasone administration on neuronal injury in neonatal rats. Methods : HI was produced in seven-day-old rats by right carotid artery ligation followed by two hours of 8% oxygen exposure. At the end of HI, the animals were injected intraperitoneally either with dexamethasone(0.5 mg/kg) or saline. Neuronal injury was assessed seven days after the HI by the area of infarction, TUNEL reactivity, Bcl-2 and Bax expression in brain. Results : Post-insult dexamethasone administration resulted in reduction of weight gain and a higher mortality rate during seven days after HI. Dexamethasone treatment revealed no effect on the size of brain infarction induced by HI. Bax protein expression increased in dexamethasone treated brain but Bcl-2 protein expression and TUNEL reactivity revealed no significant differences between dexamethasone treated and non treated brain. Increased Bax protein expression suggest upregulation of the apoptosis by dexamethasone. Conclusion : The result suggests the adverse role of Post-HI administration of dexamethasone in neonatal HI.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1422-1430
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• 2015

This study was conducted to determine the effect of fermented water extracts from Ligularia fischeri (LAF) on reduction of hepatotoxicity induced by D-galactosamine (D-GalN) in rats. In this experiment, male Sprague-Dawley rats were used as experimental animals, which were divided into eight groups: normal group, D-GalN-treated group (control), D-GalN and non-fermented water extracts from Ligularia fischeri (LA)-treated groups [100, 200, and 400 mg/kg BW (body weight)], and D-GalN and LAF-treated groups (100, 200, and 400 mg/kg BW). ${\gamma}$-Glutamyl transferase, aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase activities in serum of the D-GalN and LAF-treated groups decreased significantly compared to those of the control group (P<0.05). The high density lipoprotein-cholesterol levels of the D-GalN and LAF-treated groups increased significantly compared to those of the control group (P<0.05). The low density lipoprotein-cholesterol and triglyceride levels of the D-GalN and LAF-treated groups decreased significantly compared to those of the control group (P<0.05). The atherogenic index values of the D-GalN and LAF-treated groups decreased significantly compared to those of the control group (P<0.05), and their high density lipoprotein cholesterol by total cholesterol ratio increased significantly in these groups (P<0.05). Superoxide dismutase activity of liver tissues were enhanced significantly (P<0.05) in the D-GalN and LAF-treated groups compared to that of the control group (P<0.05), whereas their malondialdehyde content decreased significantly in these groups (P<0.05). The histopathological observations revealed apoptotic cells and mild portal inflammation in liver tissues of the D-GalN and LAF-treated groups. Taken together, these results demonstrate that LAF may improve plasma lipid profile and alleviate hepatic damage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.2
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• pp.160-165
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• 2012

A field study was conducted at Miryang in 2011 to evaluate differential sensitivity of six rice cultivars, three Indica${\times}$Japonica rice (long grain, cv. Hanareumbyeo, Hanareum2, Dasanbyeo) and three Japonica rice (short grain, Nampyung, Ilpumbyeo and Junamjosaeng) cultivars, to benzobicyclon, mesotrione+pretilachlor (MP) and butachlor (control) in transplanting rice and their treatment influences on rice yield. All Indica${\times}$Japonica rice cultivars exhibited susceptible to both benzobicyclon and MP as reflected by higher visual injury and carotenoid biosynthesis inhibition when compared with Japonica rice cutlivars. The percentage of foliar chlorosis of Indica${\times}$Japonica rice was only 0.9~4.7% for benzobicyclon at 13 days after treatment (DAT) and 30.3~64.4% for MP at 5DAT but it increased rapidly to 88.4~91.2% at 12~20DAT. However, most of the Japonica cultivars are tolerant to bezobicyclon and MP. There was no visible leaf chlorosis but carotenoid biosynthesis was slightly inhibited. Based on relative carotenoid content reduction of benzobicyclon and MP to butachlor, the Indica${\times}$Japonica rice showed 4.6~15.6 fold higher compared with the Japonica rice. The heading date of the injured rice plant was delayed by 3 days and panicle number per square meter and ripened grain ratio were reduced as compared with the control treatment of butachlor. Rice yield of the Indica${\times}$Japonica rice cultivars treated with benzobicyclon and MP was reduced by 7~10%, 3~5%. respectively. The result indicates that rice cultivars vary in tolerance to HPPD-Inhibiting herbicides and Indica${\times}$Japonica rices were more susceptible than the Japonica rices to MP and benzobicyclon. Rice yield of the Indica${\times}$Japonica rices was also significantly reduced by the those herbicide treatments.

• Journal of Animal Science and Technology
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• v.52 no.5
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• pp.427-434
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• 2010

This study was conducted to investigate the growth performance and meat quality improvement according to castration, optimal feeding management and ruminally protected amino acid-enriched fatty acid (RPAAFA) for the unselected Hanwoo bulls in the performance test. Bulls were castrated at approximately 14 months of age. Sixteen Hanwoo steers, 15 months of age and weighing $412.9{\pm}24.9kg$, were distributed into 2 groups. Steers were fed a basal diet supplemented with RPAAFA at 0 g (control) or 100 g (treatment), respectively for 12 months. Steers were slaughtered at 27 months of age. Average daily gain for treatment tended to be higher (p=0.10) than that of control, whereas feed conversion ratio tended to be lower (p=0.07) in treatment than in control. The supplementation of RPAAFA did not affect rib eye area, back fat thickness, meat color, fat color, texture and maturity. The appearance rates of yield 'A' grade and high quality grade ($1^{++}$, $1^+$ and 1) were higher in treatment than in control. The content of moisture, fat, protein and ash in longissimus muscles were similar between control and treatment. The supplementation of RPAAFA did not affect water-holding capacity, oxidation and reduction potential, myoglobin and fatty acid contents in longissimus muscles. Thus, present results indicate that castration, optimal feeding management and RPAAFA may be recommended for improving growth performance and quality grade of the unselected Hanwoo bulls in the performance test.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.4
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• pp.89-99
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• 2005

The golf courses more than about 200 are operating in Korea. From the golf courses, a great amount of turfgrass clippings tend to increase, steadily. Materials used in the experiment were Creeping Bentgrass(CB), Kentucky Bluegrass(KB), Korean Lawngrass(KL), rice bran and composted chicken drop. Treatments are CB, KB, and KL. The temperature during the composting of all treatments increased rapidly and reached at the highest temperature($57.9^{\circ}C$, $67.8^{\circ}C$, $74.3^{\circ}C$) within 20 days, and then stabilized to the range of $35.2{\sim}41.6^{\circ}C$ at the 30th day. The pH values of all treatments decreased on the first day. However, they were increased rapidly after three days and decreased again on 10~20 days. The pH values of all treatments at the final day were stabilized to the low alkali levels. The contents of total carbon during the period of composting tend to decrease and total nitrogen was increased for factor of reduction of volume. CEC value of all treatments during the period of composting tends to increase. The round paper chromatogram of extracted solution of KL sample was the sharpest and clearest among all treatments. The G.I. values of CB, KB, and KL in 30th day of composting were about 95.1, 77.7, and 98.7 in germination test using chinese cabbage, respectively. Conclusively, all turfgrass clippings used in this experiment were composted well, suitable as composting products standardized by KSC. The maturity of the final compost samples is best in KL, followed by CB and KB treatments. The turfgrass compost can contribute to the plant cultivation for environment-friendly farm, and the results of this study can become the basic data of turfgrass clippings compost. Further research on the mixing ratio of each material is required to produce compost of good quality.

• Radiation Oncology Journal
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• v.27 no.4
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• pp.228-239
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• 2009

Purpose: 4DCT scans performed for radiotherapy were retrospectively analyzed to assess the possible benefits of respiratory gating in non-small cell lung cancer (NSCLC) and established the predictive factors for identifying patients who could benefit from this approach. Materials and Methods: Three treatment planning was performed for 15 patients with stage I~III NSCLC using different planning target volumes (PTVs) as follows: 1) PTVroutine, derived from the addition of conventional uniform margins to gross tumor volume (GTV) of a single bin, 2) PTVall phases (patient-specific PTV), derived from the composite GTV of all 6 bins of the 4DCT, and 3) PTVgating, derived from the composite GTV of 3 consecutive bins at end-exhalation. Results: The reductions in PTV were 43.2% and 9.5%, respectively, for the PTVall phases vs. PTVroutine and PTVgating vs. PTVall phases. Compared to PTVroutine, the use of PTVall phases and PTVgating reduced the mean lung dose (MLD) by 18.1% and 21.6%, and $V_{20}$ by 18.2% and 22.0%, respectively. Significant correlations were seen between certain predictive factors selected from the tumor mobility and volume analysis, such as the 3D mobility vector, the reduction in 3D mobility and PTV with gating, and the ratio of GTV overlap between 2 extreme bins and additional reductions in both MLD and $V_{20}$ with gating. Conclusion: The additional benefits with gating compared to the use of patient-specific PTV were modest; however, there were distinct correlations and differences according to the predictive factors. Therefore, these predictive factors might be useful for identifying patients who could benefit from respiratory-gated radiotherapy.

• Pediatric Infection and Vaccine
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• v.7 no.2
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• pp.211-217
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• 2000

Purpose : Salmonellosis including typhoid fever is still prevalent in Korea. Recently it has been reported that the incidence of salmonella gastroenteritis is increasing with a reduction of typhoid fever. We studied the clinical and laboratory features of salmonellosis. Methods : We evaluated the clinical records of 83 patients with salmonellosis who had been confirmed by stool culture from 1994 to 1999. Results : Annual incidence of salmonellosis showed an increasing tendency during recent 4 years. Seasonally, summer(45.8%) was the most prevalent, followed by fall(32.5%). Male to female ratio was 1.4 : 1. In age distribution, 64 cases(77.1%) were under 5 year-old, and 18 cases(21.7%) were younger than 1 year-old. Clinical features included diarrhea(96.4%), fever(91.6%), vomiting(49.4%), bloody stool(42.1%), abdominal pain(40.1%) and tenesmus(12.0%). In serogroups, there was no group A and group B, group C, group D(including 2 cases of S.typhi) and group E were in 41.0%(34 cases), 3.6%(3 csaes), 51.8%(43cases) and 3.6%(3 cases), respectively. In Widal test, 5 cases(13.5%) and 1 case(2.7%) of group B, C and E(total 37 cases) were observed the O titer above 1 : 80 and 1 : 320, respectively. However, in 36 cases of group D, 19 cases(52.7%) and 9 cases(25.0%) were above the O titer 1 : 80 and 1 : 320, respectively. Antibiotics resistant rates to ampicillin, trimethoprim/sulfamethoxazole and chloramphenicol were 23.2%, 10.1% and 51.4%, respectively. Conclusion : Salmonellosis has become a common cause of gastroenteritis in children, especially under the pre-school age. Isolation of salmonella is neccessary for accurate diagnosis of gastroenteritis and typhoid fever. A careful attention of the use of antibiotics is needed to reduce the muilti-drug resistant strains.

• The Korean Journal of Nuclear Medicine Technology
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• v.12 no.1
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• pp.13-18
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• 2008

Purpose: The image processing method due to the algorism which is various portion nuclear medical image decision is important it makes holds. The purpose of this study is it applies hereupon new image processing method SIEMENS (made by Pixon co.) Onco. flash processing reconstruction and the comparison which use the image control technique of existing the clinical usefulness it analyzes with it evaluates. Materials & Methods: 1. Whole body bone scan-scan speed 20 cm/min, 30 cm/min & 40 cm/min blinding test 2. Bone static spot scan-regional view 200 kcts, 400 kcts for chest, pelvis, foot blinding test 3. 4 quadrant-bar phantom-20000 kcts visual evaluation 4. LSF-FWHM resolution comparison ananysis. Results: 1. Raw data (20 cm/min) & processing data (30 cm/min)-similar level image quality 2. Low count static image-image quality clearly improved at visual evaluation result. 3. Visual evaluation by quadrant bar phantom-rising image quality level 4. Resolution comparison evaluation (FWHM)-same difference from resolution comparison evaluation Conclusion: The study which applies a new method Onco. flash processing reconstruction, it will be able to confirm the image quality improvement which until high level is clearer the case which applies the method of existing better than. The new reconstruction improves the resolution & reduces the noise. This enhances the diagnostic capabilities of such imagery for radiologists and physicians and allows a reduction in radiation dosage for the same image quality. Like this fact, rising of equipment availability & shortening the patient waiting move & from viewpoint of the active defense against radiation currently becomes feed with the fact that it will be the useful result propriety which is sufficient in clinical NM.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.1
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• pp.134-139
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• 2014

Purpose: Adaptive statistical iterative reconstruction (ASIR) technique is a reconstruction method of CT image using statistical noise modeling which is known to reduce image noise and to preserve image quality despite reducing radiation dose. The aim of this study is to evaluate images using ASIR on bone SPECT/CT which is primarily performed in our hospital. Materials and Methods: We compared the images of applied ASIR (ASIR level: 20-80%) and none ASIR by changing the mA based on 120 kVp, 100 mA using Discovery NM/CT 670 (GE, U.S.A). First, we evaluated attenuation correction in SPECT image by changing the ASIR level using Anthropomorphic phantom. Second, we compared the contrast to noise ratio (CNR), image noise and spatial resolution in CT image using ACR phantom. Third, after selecting the ASIR level applicable patient using lower torso phantom, we examined 2 patients who followed up bone SPECT/CT and we performed blind test. Results: The degree of attenuation correction in SPECT image showed no significant difference between applied ASIR and none ASIR (P>0.05). When applied ASIR, the noise of CT image were reduced at least 17 up to 52% by changing the mA. The CNR of image with ASIR was maintained more than 0.8 at 40 mA (ASIR 60%) while those without ASIR showed 0.42 at standard 40 mA. In comparison of the high contrast object, we distinguished 12 line pairs/cm at 40 mA regardless of appling ASIR. Comparison of the patients image applied ASIR level 60% (40 mA) which found out by spine image of lower torso phantom showed no signigicant difference between applied ASIR and none ASIR in blind test. The CTDIvol and DLP for applied ASIR 60% showed decreased by 60%, 60% on average than using standard mA. Conclusion: The study show that the radiation dose in SPECT/CT using ASIR can be reduced despite degradation of SPECT and CT images. In addition, higher ASIR level could be possibly applied characteristics of SPECT/CT that region of interest is limited to bone.