• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.4
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• pp.579-589
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• 2007

The objective of this study was to compare the shear bond strengths of five adhesive systems to the enamel and dentin of primary and permanent teeth. Fifty noncarious primary and fifty permanent teeth were collected and stored in an 0.1% thymol solution at room temperature after extraction. The tested adhesives were: Adper Scotchbond Multi-purpose Plus Adhesive (SM) Adper Single bond 2 (SB), Clearfil SE Bond (SE), Adper Prompt L-Pop (PL), GBond (GB). For the shear bonding test, the labial and lingual surfaces of primary and permanent teeth were used. To obtain a flat surface, the labial and lingual surfaces of the teeth were sanded on $SiO_2$ with number 600 grit and then divided into 20 groups of 10 surfaces each. All samples were theromocycled in water $5^{\circ}C$ and $55^{\circ}C$ for 1000 cycles. The results were as follows: 1. For primary enamel, shear bond strengths of SM and SB were significantly higher than that of SE and also SM, SB, and PL were higher than GB(p<0.05). 2. For primary dentin, there were no significant differences among the shear bond strengths of any other bonding systems except difference between SE and GB. 3. For permanent enamel, SB showed significantly higher mean shear bond strength than those of any other bonding systems(p<0.05). 4. For permanent dentin, SM showed significantly higher mean shear bond strength than that of PL and GB(p<0.05). 5. Between the primary enamel and dentin, there were significant differences in SM, SB, and GB, whereas there was statistically significant difference in PL between the permanent enamel and dentin(p<0.05). 6. Between the primary and permanent teeth on enamel, there were no significant differences among all bonding systems, whereas there were statistically significant differences in SM and SB between the primary and permanent teeth on dentin(p<0.05).

• Journal of Gastric Cancer
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• v.8 no.3
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• pp.154-159
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• 2008

Purpose: Although most surgeons generally administer prophylactic antibiotics for more than three days, the optimal duration of antimicrobial prophylaxis in elective gastric surgery is still open to debate. The aim of this study was to determine if the duration of prophylactic antibiotic use can affect the recovery of patients after elective gastric surgery. Materials and Methods: A total of 93 patients with gastric cancer were enrolled in this study, between January 2007 and December 2007. Patients were excluded if they had an infection at the time of surgery or they underwent an emergency operation. The first antibiotics were commonly given from just prior to the operation. The patients were divided into three groups according to the operation periods: those who received antibiotics only on the day of operation (arm A), those who received antibiotics for up to 3 days (arm B), and those who received antibiotics for more than 5 days postoperatively (arm C). The antibiotic that was used was second generation cephalosporin. Results: The rate of surgical site infection was 12.9% (n=4) in arm A, 16.1% (n=5) in arm B and 19.4% (n=6) in arm C, respectively (P=0.788). No relationship was observed between the duration of prophylaxis and the rate of fever or the neutrophil counts during postoperative 7 days (P=0.119, P=0.855). Conclusion: The prophylactic effect of antibiotics on recovery, with the antibiotics being received only on the day of the operation, is as effective as receiving antibiotics for a longer duration after gastric cancer surgery.

• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.423-429
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• 2008

Currently, Ash-free clean coal producing process by solvent extraction is under development. The produced ash-free clean coal can be directly combusted in a gas turbine which results in substantial improvement of power generation efficiency. However, the clean coal produced by the solvent extraction still contain trace amount of alkali metal which may cause corrosion on turbine blades during the direct combustion. In present work ${\alpha},{\beta}$-metal (Zr and Ti) phosphates and H-Y zeolite were synthesized and their ion exchange characterizations were investigated for the application on alkali metal removal for clean coal production. $Na^+$ ion removal capacities of the metal phosphates and H-Y zeolite were measured and compared in both aqueous solution (100 ppmw, $Na^+$) and coal dissolved N-methyl-2-pyrrolidone (NMP, 12 ppmw $Na^+$) at elevated temperature. In aqueous solution, the ${\beta}$ form metal phosphates showed very high ion exchange capacities compared to ${\alpha}$ form. ${\beta}$ form metal phosphates also showed higher $Na^+$ removal capacities than H-Y zeolite. In ion exchange medium of NMP, all the ${\alpha}$ form metal phosphates showed over 90% of $Na^+$ ion removal efficiency in the temperature range of 200 to 400 while that of H-Y zeolite decreased as a half when the temperature was over 350. In addition, the regenerated metal phosphates by acid treatment showed no sign of degradation in $Na^+$ removal efficiency. Among the metal phosphates used, $Zr_{0.75}Ti_{0.25}(HPO_4)_2$ showed the best performance in $Na^+$ removal and is expected to be the most suitable inorganic ion exchanger for the alkali metal removal process.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.10
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• pp.1555-1564
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• 2014

This study investigated the effects of combined treatment of immersion liquids (adjusted pH 4.5 with Citrus junos concentrate (CL), pH 5.5 with Prunus mume concentrate (PL), or no pH adjustment, pH 6.5, control) and high hydrostatic pressure (HHP, 450 MPa) on shelf-life and quality of mackerel. In this study, we measured changes in viable cell counts, pH level, volatile basic nitrogen, thiobarbituric acid reactive substances, color analysis, volatile organic compounds, and sensory evaluation of mackerel at $4^{\circ}C$ for 20 days. CL/HHP and PL/HHP treatments reduced viable cell counts by 3 log cycles during storage compared to the control. Mackerel treated with CL/HHP and PL/HHP showed significantly lower TBARS and VBN levels as compared to the control. After combined treatment, lightness and whiteness increased but redness decreased. VOCs tests showed that contents of alcohol, acid, and ketones in mackerel fillet treated with CL/HHP and PL/HHP were relatively reduced. Especially, CL/HHP and PL/HHP suppressed production of sulfur. In the sensory evaluation, aroma, taste, salinity, hardness, and springiness of mackerel treated with combined HHP showed higher scores than the control. These results suggest that immersion liquids and HHP treatments may increase shelf-life of mackerel and maintain quality during storage at $4^{\circ}C$.

• The Korean Journal of Malacology
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• v.24 no.3
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• pp.215-228
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• 2008

This study was performed to find out the community structure of macrobenthos and the environmental factors around Munseom coastal water in Jeju Island from June to December, 2007. Mean temperature and mean salinity were $19.6^{\circ}C$ and 34.03 psu, indicating stable water masses. Concentrations of DO, COD and SS were as low as those in the standard sea-water-quality classes I. Chlorophyll a concentrations ranged from 0.40 to 1.09 mg/L (mean, 0.69 mg/L), and higher concentration was observed in December rather than in June due to a blooming in winter. The mean concentration (their ranges are in parentheses) of nitrate, phosphate, and silicate were 0.15 mg/L (0.073-0.264 mg/L), 0.01 mg/L (0.004-0.011 mg/L) and 0.23 mg/L (0.039-0.464 mg/L), respectively. The values were higher near the Munseom due to influxes from the land. Of the 112 species that were identified, 40 species (36.0%) were Mollusca; 33 (28.8%) were Cnidaria; 13 (11.7%) were Porifera; 8 (7.2%) were Arthropoda and 17 species (15.3%) were others including Echinodermata. Density and biomass were estimated to be 4,340 individual/$m^2$ and $53,107.8\;gwwt/m^2$ respectively. Anthozoa was the most dominant group in abundance ($2,132\;ind./m^2$) as well as in the number of species, whereas Cnidaria was predominant in biomass ($37,630.9\;gwwt/m^2$). The dominant species were Dendronephthya gigantea, Scleronephthya gracillimum, Anthoplexaura dimorpha, Dendronephthya castanea, Thecocarpus niger, Dendronephthya spinulosa, Dendronephthya putteri, and Acabaria bicolor in the depth of 10-30 m. The seasonal variations of the number of individual and biomass of Cnidaria and Mollusca were observed. There was a slow increment in June, a decrement in October, and a drastic increasing in December. The biodiversity, evenness and richness index in surveyed stations were 2.715-3.413 (H'), 0.758-0.851(E'), and 5.202-8.720 (R) respectively. The dominance index was the highest in station M2 and the lowest in station M1.

• Journal of the Korean Arthroscopy Society
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• v.15 no.2
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• pp.99-107
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• 2011

Purpose: The purpose of this study was to investigate the clinical results after a anatomical double bundle ACL reconstruction using a longitudinally split tibialis anterior allograft. Materials and Methods: We evaluated 24 patients with a minimum follow-up of 12 months who had undergone anatomical double bundle ACL reconstructions. The grafts utilized in all cases were tibialis anterior allografts which were longitudinally split into two strands. A standard rehabilitation protocol was applied in all patients. The pre- and post-operative data including Lysholm scores, International Knee Documentation Committee (IKDC) scores, Lachman test, pivot shift test and the side-to-side differences of anterior laxity measured by KT-2000 arthrometer were analyzed by use of a statistical method Results: The mean side-to-side instrumented laxity measured by the KT-2000 arthrometer significantly improved to a mean of $1.04{\pm}0.80\;mm$ (P < 0.001). The Lysholm knee scores also improved from $58.34{\pm}15.32$ to $86.25{\pm}6.48$ after surgery (P < 0.001). The patients exhibited improved IKDC scores (A: 15 cases, B; 9 cases) at the final follow-up, compared to preoperative scores (B: 5, C: 10, D: 9). Conclusion: Our data demonstrated that clinical results of anatomical double bundle ACL reconstruction with a split tibialis anterior allograft are encouraging with excellent side-to side laxity, significantly improved Lysholm knee score, IKDC score, Lachman and pivot shift data.

• Journal of the Korean Chemical Society
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• v.35 no.2
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• pp.119-127
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• 1991

The protonation and the metal ion complexation of 15 to 18 membered diaza crown ether such as 1,12-diaza-3, 4 : 9, 10-dibenzo-5, 8-dioxacyclopentadecane(NtnOenH$_4$), 1,13-diaza-3,4 : 10,11-dibenzo-hydroxy-5,9-dioxacyclohexadecane(NtnOtnH$_4$), 1,13-diaza-3,4 : 10,11-dibenzo-15-hydroxy-5,9-dioxacyclohexadecane(Ntn(OH)OtnH$_4$), 1,15-diaza-3,4 : 12,13-dibenzo-5,8,11-trioxacycloheptadecane (NenOdienH$_4$) and 1,15-diaza-3,4 : 12,13-dibenzo-5,8,11-trioxacyclooctadecane(NtnOdienH$_4$) were studlied by potentiometry and NMR spectroscopy. The protonation constants were used to predict basicity of crown ethers. The sequence of the basicity was NenOdienH$_4$ < Ntn(OH)OtnH$_4$ < NtnOenH$_4$ < NtnOtnH$_4$ < NtnOdienH$_4$. Changes on the basicity were explained in terms of the effects of substituents and the degree of twistness of the macrocyclic ring. The sequence of the complex stabilities were Co(II) < Ni(II) < Cu(II) < Zn(II) for the transition metal complexes and Cd(II) < pb(II) < Hg(II) for the post-transition metal complexes. These changes on the stabilities were dependent on the basicity of the ligand and cavity size of the ring. For the heavy post-transiton metal complexes and Zn(Ⅱ) complex, the former factor was predominent and for the other transition metal complexes, the latter was affected on the stabilities. $^1$H and $^{13}$C-NMR studies for heavy post-transition metal complexes indicated that the nitrogen atom has greater affinity on metal ions than oxygen atom and the planarity of the rings was losed by the complexation with metal ions.

• Journal of Bio-Environment Control
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• v.26 no.3
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• pp.158-166
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• 2017

The object of this study was to improve tomato seedling quality in low temperature(below 7, $10^{\circ}C$ during night time or daily mean air temperature was $18^{\circ}C$) by application of silicate fertilizer. Six different silicate fertilizer concentrations (8, 16, 32, 64, 128, and 256mM) or water as the control were applied to tomato seedlings twice a week for 20 days. Positive effects were observed in the growth parameters of the seedlings treated with 16 and 32mM silicate fertilizer; the most effective concentration of silicate at which seedlings showed the best performance was 16mM. However, a high concentration of silicate (256mM) caused negative effects on the growth. The transpiration rate decreased alongside with the increase of silicate concentration up to 32mM, possibly due to the increased stomatal diffusive resistance. Silicate stimulated the growth and development of tomato seedlings, resulting in increased growth parameters and root morphology. However, no significant differences were observed among treatment numbers of soil-drenching wuth the silicate (6, 10, or 20 times with 16mM) for 20 days, suggesting that silicate treatment with 6 times may be sufficient to induce the silicate effects. The application of 16mM of silicate fertilizer reduced relative ion leakage and chilling injury during low temperature storage. In addition, the seedlings treated with silicate fertilizer recovered faster than those without silicate treatment after low temperature storage.

• Journal of the Korean Society of Radiology
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• v.6 no.1
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• pp.73-77
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• 2012

Recently, Interest to the photoconductor, which is used to flat form X-ray detector such as a-Se, $HgI_2$, PbO, CdTe, $PbI_2$ etc. is increasing. In this study, the film layer by using the photoconductive material with particle sedimentation was fabricated and evaluated. The quantization efficiency of the continuous X-ray with the 70 kVp energy bandwidth was analyzed by using the Monte Carlo simulation. With the results, the thickness of film with 64 % quantization efficiency was 180 ${\mu}m$ which is similar to the efficiency of 500 ${\mu}m$ a-Se film. And $HIg_2$ film has the high quantization efficiency of 74 % on 240 ${\mu}m$ thickness. The electrical characteristics of the 239 ${\mu}m$ $Hgl_2$ films produced by particle sedimentation were shown as very low dark current(under 10 $pA/mm^2$), and high sensitivity(19.8 mC/mR-sec) with 1 $V/{\mu}m$ input voltage. The SNR, which is influence to the contrast of X-ray image, was shown highly as 3,125 in low driving voltage on 0.8 $V/{\mu}m$. With the results of this study, the development of the low-cost, high-performance image detector with film could be possible by replacing the film produced by particle sedimentation instead to a-Se detector.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.1
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• pp.33-41
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• 2011

The objective of this study was to compare the shear bond strengths of five dentin adhesive systems cured with three different light curing sources. Seventy five noncarious permanent teeth were collected and stored in an 0.1% thymol solution at room temperature after extraction. The tested adhesives were: Adper Scotchbond Multi-purpose Plus Adhesive (SM) Adper Single bond 2 (SB), Clearfil SE Bond (SE), Adper Prompt L-Pop (PL), G-Bond (GB). And three light curing unit systems were used: Elipar Free light 2(LED), OptiLux 501 (Halogen), Flipo (PAC). For the shear bonding test, the labial and lingual surfaces of permanent teeth were used. To obtain a flat dentin surface, the labial and lingual surfaces of the teeth were sanded on SiO2 with number 600 grit and then divided into 15 groups of 10 surfaces each. All samples were theromocycled in water $5^{\circ}C$ and $55^{\circ}C$ for 1000 cycles. The results were as follows: 1. When cured with Freelight 2, the shear bond strength of SM was significantly higher than that of PL, GB (p<0.05), whereas no significant difference was found among those of any other bonding agents. 2. When cured with Optilux 501, the shear bond strength of SM was significantly higher than those of any other bonding agents (p<0.05), whereas no singnificant difference was found among those of andy other bonding agents. 3. When cured with Flipo, the shear bond strength of SM was significantly higher than those of SB, SE, GB (p<0.05), whereas no significant differences was found among those of any other bonding agents. 4. For comparison according to three different light cure unit system, except SB and GB, each three dentin bonding agents showed no significant difference. For SB, only Freelight 2 was significantly higher than the others, with no significant difference between Optilux 501 and Flip. For GB, Statistically significant difference was found only between Freelight and Flipo.