• The Journal of Korean Academy of Prosthodontics
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• v.48 no.2
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• pp.158-165
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• 2010

Purpose: The objective of the present study was to histologically evaluate durability and bone regeneration capacity of new synthetic membranes in comparison to clinically available collagen membrane. Material and methods: To the skulls of 12 rabbits, we created 4 bone defects of 6 mm in diameter on each of them. Each of defects were covered with at least one of 5 membranes; No membrane, Collagen ($Ossix^{TM}$), PLGA, HA-coated-PLGA and HA-PLGA/PLGA. After 4, 8, 12 weeks, we cut the skulls and dyed with H-E. And then, the histologic observation was done. Results: In current study, the control group which did not use the membrane showed bone regeneration at 12 weeks and covered the bone defect partially. New bones were formed through the underneath of endocranium, and the upper defect was filled with connective tissues and fats. Collagen membrane ($Ossix^{TM}$) showed new bones after 4 weeks, and they were formed through the membrane which maintained until 12 weeks. PLGA, HA-coated-PLGA, HA-PLGA/PLGA showed bone regeneration after 4 weeks and after 8 weeks, they mostly filled defects. At 12 weeks, we could find new bones and previous bones almost look alike and also, they united well. Membranes were unnoticeable after 4 weeks and were absorbed. Conclusion: Bone formation and maturation of PLGA, HA-coated-PLGA and HA-PLGA/PLGA were faster than the control group. They showed no difference on the application of HA and after 4 weeks, they were absorbed.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.2
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• pp.151-157
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• 2010

Purpose: The purposes of this study was to evaluates shear bond strength between zirconia core and veneer-ceramic in order to examine the clinical practice of colored zirconia block fabricated by infiltration method into the metal chloride solution. Material and methods: CNU block and $Everest{(R)}$ ZS blank were used. VITA In-$Ceram{(R)}$2000 YZ Coloring liquid (LL1) and 3 aqueous metal chloride solutions containing chromium and molybdenum ingredients were used. 40 zirconia specimens were prepared into cuboid shape ($5{\times}5{\times}10 mm$). All specimens were divided into 5 groups by infiltrating into the coloring liquids. After that, porcelain was build up into the shape of $5{\times}5{\times}4mm^3$, followed by sintering. The maximum loading and shear bond strength was measured. Failure patterns and failure sites were examined. Results: 1. There were no statistical differences in shear bond strength between zirconia blocks (P > .05). 2. There were no statistically significant differences in shear bond strength between non-colored and colored zirconia blocks, while shear bond strength of non-colored zirconia blocks is higher than that of colored specimen (P > .05). 3. In the comparison with shear bond strength among colored zirconia blocks, there were no statistical differences according to kinds of coloring liquid (P > .05). 4. Mixed failure patterns were mainly observed in the failure between zirconia and veneering ceramic. The veneering ceramic failure of all specimens was observed in either interface of zirconia or veneering ceramic. Conclusion: Shear bond strength between colored zirconia and veneering ceramic shows lower tendency than non-colored zirconia, but there was clinically allowable value.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.4
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• pp.632-640
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• 2002

The objective of the study was to apply the vibration technique to reduce the viscosity of bonding adhesives and thereby compare the bond strength and resin penetration into dentinal tubules achieved with those gained using the conventional technique. Eighty-eight noncarious extracted human permanent molar teeth were sectioned to remove the coronal enamel and were embedded in 1-inch PVC pipe with acrylic resin. The occlusal surfaces were placed so that the tooth and the embedding medium were at the same level to form one flat surface, and the samples were subsequently polished with silicon carbide abrasive papers. The samples were randomly assigned to 4 groups(n=22). On Group 1 and 2, Single Bond(3M-ESPE, St. Paul, USA) was used, and on Group 3 and 4, One-Step(Bisco Inc., Schaumburg, USA) was used, and each was applied according to its manufacturer's instructions. For Group 2 and Group 4, vibration was applied with ultrasonic scaler for 10 seconds, and the adhesive was light-cured for 10 seconds. Resin composite was condensed on to the prepared surface in two increments using a mold kit(Ultradent Products Inc., USA) and each was light-cured for 40 seconds. After 24 hours in tap water at room temperature the specimens were thermocycled, and shear bond strengths were measured with a universal testing machine(Instron 4465, Canton, USA). To investigate infiltration patterns of the adhesive materials, the surface of specimen was examined with scanning electron microscope. The results were as follows. 1. The shear bond strengths of vibration groups(Group 2, Group 4) were significantly greater than those of the non-vibration groups(Group 1, Group 3)(p<0.05). 2. The shear bond strengths of Single Bond and One-Step were not significantly different (p>0.05). 3. The vibration groups showed greater number of resin tags in tubules and lateral branches under SEM.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.2
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• pp.287-296
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• 2008

The purpose of this in vitro study was to compare the remineralization effect of commercially available anticariogenic products, exactly low level fluoride mouthrinse(500 ppm NaF), tooth cream with Casein phosphopeptide-amorphous calcium phosphate(CPP-ACP) and fluoride mouthrinse plus tooth cream on artificial caries lesion. Artificial caries lesion was induced at the buccal surface of permanent third molar and the specimens were then divided(16 specimens/group) into four group. Twice a day during 28 days specimens of each group were treated with a commercially anticariogenic product as follows and applied to the pH cycling system. Group 1: control group (No treatment) Group 2: Tooth $Mousse^{(R)}$ (GC Co. Japan) Group 3: $chikachika^{(R)}$ (Samil Co. Korea) Group 4: $chikachika^{(R)}$+Tooth Mousse$^{(R)}$ The long-term change of mineral loss(${\Delta}Q$) was evaluated by quantitative light-induced fluorescence (QLF) and the following results were obtained: 1. ${\Delta}Q$ of Group 1 was not noticed statistically significant during 28 days comparing that prior to treatment. There was a statistically significant increase in ${\Delta}Q$ of Group 2 and 3 since 14 days. So was in ${\Delta}Q$ of Group 4 since 7 days. 2. ${\Delta}Q$ was increased as follows: Group 1< Group 2, 3< Group 4. 3. Comparing with Group 1, Group 2 was a statistically significant increase since 7 days and Group 3 and 4 were since 3 days. Comparing Group 2 with 3, there was not noticed statistically significant during whole duration. Group 4 was significantly higher than Group 2 and 3 after 28 days. 4. All groups demonstrated a decrease in the rate of remineralization as time goes on.

• The Korean Journal of Air & Space Law and Policy
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• v.4
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• pp.65-85
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• 1992

The air waybill is supposed to be made out by the consignor. If the carrier makes it out, he is deemed, subject to proof to the contrary, to have done so on behalf of the consignor. The air waybill shall be made out in three original parts. The first part shall be marked "for the carrier", and shall be signed by the consignor. The second part shall be marked "for the consignee", it shall be signed by the consignor and by the carrier and shall accompany the goods. The third part shall be signed by the carrier and handed by him to the consignor, after the goods have been accepted. According to the original Warsow Convention article 8, the air waybill must contain 17 particulars or items. However, the Hague Protocol reduced to three the number of particulars required to appear on the air waybill. Only one item is obligatory, namely, the notice that the carriage is subject to the rules of the Warsaw Convention. The absence of the air waybill entails unlimited liability of the carrier because it deprives him of the right to avail himself of the provisions of the Warsaw Convention which exclude or limit his liability. The consignor shall be liable for all damages suffered by the carrier or any other person by reason of the irregularity, incorrectness or incompleteness of the particulars and statements in the air waybill. Although the contract of the carriage of goods by air is not a formal contract, the document of carriage is issued. The issue of air wayhill is not essential for the existence or validity of the contract, but serves merely as a means of proof. The Hague Protocol has lessened the consequences of the carrier's neglect to faithfully accomplish the required formalities. Henceforth, these formalities no longer constitute legal obligations. The air waybill is the consignment note used for the carriage of goods by air. It is often called an air consignment note and is not a document of title or transferable/negotiable instrument. It is basically a receipt for the goods for despatch and is prima facie evidence of the conditions of carriage. Each of the original parts of the air waybill has evidential value and possession of his part is a condition for the exercise by the consignor or cosignee of his rights under the contract of carriage. Oveall, it is an usage that under a documentary letter of credit, the consignee on the air waybill is the opening bank of the letter of credit, and the notify party is the importer who applied for the letter of credit. In Korea there is an usage as to process of cargo delivery in air transportation as follows: The carrier carries the cargo into the bonded area of the airport and gives both the notice of arrival of the cargo and the consignee's air waybill to the notify party who is the importer. Then the notify party obtains the Letter of Guarantee from the opening bank in exchange for reimbursing the amount of the letter of credit or tendering the security therefor to the opening bank. The notify party then presents this document to the customs authorities for the process of customs clearance. The opening bank becomes a consignee only to ensure repayment of the funds it has expended, and the only interest of the opening bank as consignee is the reimbursement of the money paid to the exporter under the documentary letter of credit. Just as the bill of lading in maritime law, the air waybill has always been considered negotiable although the Warsaw Convention does not emphasize this aspect of negotiability. However, the Hague Protocol article 4 corrected the situation by stating that "nothing in this Convention prevents the issue of a negotiable air waybill." This provision officially recognizes that the air waybill must meet the needs of the present day business circles by being a negotiable instrument. Meanwhile, Montreal Additional Protocol no. 4 has brought important changes. Registration by computer is acceptable and the parties to the contract of carriage are allowed to replace the air waybill with a receipt for the goods. In conclusion, as the Warsaw Convention has not details of provisions relating to the issuing of the negotiable air waybill, it is hoped that there should be supplement to the Warsaw Convention and establishment of international commercial usage with regard to the negotiable air waybill.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.6
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• pp.924-932
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• 2013

This study investigated the antioxidant activities of processed Deoduck (Codonopsis lanceolata) extracts treated through high-pressure extraction and steaming with fermentation. The antioxidant activities were determined for DPPH and ABTS radical-scavenging activity, SOD-like activity, ferric reducing antioxidant power (FRAP), and $Fe^{2+}$ chelating. Total phenolic and flavonoid contents were also measured. Among eight Deoduck extracts, the S5FDW extract had the highest total phenolic and flavonoid content, 73.9 mg GAE/g and 50.9 mg QUE/g, respectively. The S5FDW extract had the highest DPPH radical-scavenging activity (27%) at a 1.0 mg/mL concentration. The ABTS radical-scavenging activity was highest for S5FDW extract (82.1%) at a 10 mg/mL concentration. The HFDE extract showed the highest SOD-like activity (29.7%) at a 1.0 mg/mL concentration. FRAP was highest in S5FDW extract (140.8 ${\mu}M$) at a 1.0 mg/mL concentration. The DE extract showed the highest $Fe^{2+}$ chelating (46%) at a 1.0 mg/mL concentration. The phenolic and flavonoid contents significantly correlated with the antioxidant activity of several processed Deoduck extracts and was higher in the processed Deoduck extracts compared to the raw Deoduck extracts. Therefore, processing techniques can be useful methods for making Deoduck a more potent and natural antioxidant.

• Journal of Bio-Environment Control
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• v.18 no.1
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• pp.1-8
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• 2009

The greatest and major cost for cut rose production during winter seasons in Korea is cost of heating the greenhouse. A study was conducted on a cost-efficient heating system to reduce expenses of cut rose growers in times of high energy prices. An infrared heating system utilizing radiant energy has an obvious advantage over other heating methods in that the energy is first used to raise temperatures of plants and other objects and subsequently that of the atmosphere, resulting in faster reaching to desired plant temperatures at a reduced heating cost. In this study the heating effect and heating cost saving of a nano-carbon fiber infrared heating system (NCFIHS) installed in cut rose greenhouses in Gimhae, Gyeongnam Province were analyzed comparatively. In addition growth, quality, and vase life of 'Orange Fresh' roses grown in greenhouses heated by NCFIHS against those grown in greenhouses heated by so called an electrical heating system. In greenhouses with a NCFlHS with a set point air temperature of $20^{\circ}C$, plant temperature was maintained at $1{\sim}2^{\circ}C$ higher than the air temperature, and temperatures of growing bed surface and root zone were maintained at $17{\sim}19^{\circ}C$ throughout cold winter nights. The cost for heating in NCFIHS was about 25 and 51% of that of an electrical heating system and a hot water heating system heated by petroleum, respectively. Growth of roses harvested in greenhouses with a NCFIHS was similar to those grown in greenhouses with an electrical heating system. However, cut roses with more intense petal and leaf colors and a longer vase life (fresh weight and amount of water uptake) were harvested in greenhouses with a NCFIHS as compared to those harvested in greenhouses with an electrical heating system.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.344-353
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• 2020

Plants native in Korea have not only ornamental values but also have excellent environmental adaptability, so they can be used as garden plants. Studies on proper volumetric water content (VWC) of substrates have been reported, but many have been conducted in glasshouse conditions where environmental factors were controlled. When considering garden planting, it is necessary to perform the automated irrigation system in outdoor conditions where rainfall occurs at frequent intervals. This research aimed to investigate the VWC suitable for the growth of Minuartia laricina, Arenaria juncea, and Corydalis speciosa in open filed. Sandy soil which consisted of particles of weathered rock was used, and the VWC of 0.15, 0.20, 0.25, and 0.30 ㎥·m^-3 was maintained using an automated irrigation system with capacitance soil moisture sensors and a data logger. No significant differences in growth and antioxidant enzymes activity of A. juncea were observed among VWC treatments. However, the survival rate was low at VWC 0.30 ㎥·m^-3 treatment, which was the highest soil moisture content. Even considering the efficiency of water use, we recommended that VWC 0.15-0.20 ㎥·m^-3 is suitable for the cultivation of A. juncea. Minuartia laricina showed better growth with lower VWC. Because of frequent rainfall in open field, plant volume and survival rate was high even in VWC 0.15 ㎥·m^-3 treatment. In C. speciosa, the plant height, number of shoots and lateral shoots, and fresh and dry weight were higher in plants grown in VWC 0.25 ㎥·m^-3 as compared with that in the plants grown at 0.15, 0.20, and 0.30 ㎥·m^-3. Based on these results, M. laricina needed less water in open filed, and A. juncea and C. speciosa required higher VWC, but excessive water should be avoided.

• Journal of Distribution Research
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• v.15 no.1
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• pp.73-101
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• 2010

Using data collected from franchisees from Busan, we empirically examined the relationship both structural (tie strength), relational (trust), and cognitive (shared value) of social capital and between those dimensions and the patterns of economic performance and noneconomic performance (relationship continuity intention). So we established 9 hypotheses to test the structural relationship among dimensions of social capital and performances like below. H1: A franchisee's perceived tie strength with its franchisor will positively influence its trust in the franchisor. H2: A franchisee's perceived shared value with its franchisor will positively influence its trust in the franchisor. H3: A franchisee's perceived tie strength with its franchisor will positively influence its economic performance. H4: A franchisee's perceived shared value with its franchisor will positively influence its economic performance. H5: A franchisee's perceived trust in its franchisor will positively influence its economic performance. H6: A franchisee's perceived tie strength with its franchisor will positively influence its relationship continuity intention with the franchisor. H7: A franchisee's perceived shared value with its franchisor will positively influence its relationship continuity intention with the franchisor. H8: A franchisee's perceived trust in its franchisor will positively influence its relationship continuity intention with the franchisor. H9: A franchisee's perceived economic performance will positively influence its relationship continuity intention with the franchisor. The conceptual model specifying the relationship among dimensions of social capital and performances is presented in Fig. 1. Tests of the hypotheses were performed using a structural equation model. This model also reflected a good fit to the data ($\chi^2$=101.12 df=62 p=0.004, RMSEA=0.050 GFI=0.936 AGFI=0.895 NFI=0.959 CFI=0.986). The standardized solution estimated by the AMOS 7 program was for interpreting the structural results (Table 1). As was expected, tie strength and shared value were founded to be significant predictors of trust (H1 supported; H2 supported). Tie strength and trust have a significant positive effect on economic performance (H3 supported; H5 supported). But shared value have not a significant effect on economic performance (H4 Rejected). Tie strength were not associated with relationship continuity intention (H6 Rejected). While on the other higher shared value, trust, and economic performance have a significant effect on the relationship continuity intention (H7 supported; H8 supported; H9 supported). The results show integratedly that, first, tie strength does not affect directly but affects indirectly on relationship continuity intention via trust and economic performance. Second, shared goals affect directly and do indirectly via trust on relationship continuity intention. But shared goals does not affect via economic performance on relationship continuity intention. Finally, the study suggests important implications for both research and practice for franchise system especially.

• Clinical and Experimental Pediatrics
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• v.49 no.7
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• pp.790-795
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• 2006

Purpose : This study was performed to compare the therapeutic effects according to duration of medium-dose aspirin(50-60 mg/kg/day) therapy at the acute stage of Kawasaki disease(KD). Methods : Total 87 patients with KD were enrolled in this study. We performed retrospective analysis of clinical characteristics and echocardiographic findings based on medical records. Patient were randomly divided into 2 groups according to the duration of aspirin therapy at the acute stage of KD. Long-term group(LG, n=55) was administered medium-dose aspirin for 2 weeks after diagnosis of KD, and short-term group(SG, n=32) for 48 hours after intravenous immunoglobulin(IVIG) administration. The parameters of therapeutic effects were duration of fever after IVIG administration, incidence of unresponsive patients to single administration of IVIG, and development of transient dilatation or aneurysm of coronary arteries. Results : There was no significant difference in the duration of fever after IVIG between the both group(LG $1.7{\pm}1.1$ days, SG $1.8{\pm}1.1$ days; P=0.588). The incidences of unresponsive patient to the single administration of IVIG were 5.5 percent, 6.3 percent in the each group. Transient dilatation of coronary arteries occurred at 18.2 percent(10/55) in the LG, and 15.6 percent(5/32) in the SG(P=0.761). Prevalence of coronary aneurysm after subacute stage were 7.3 percent(4/55) in the LG, and 9.4 percent(3/32) in the SG(P=0.728). Conclusion : There was no significant difference in the therapeutic effects between long-term(2 weeks) and short-term(48 hours) administration of medium-dose aspirin at the acute stage of KD.