• Environmental Engineering Research
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• v.24 no.1
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• pp.38-44
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• 2019

The Biochemical Methane Potential (BMP) of fresh leachate and domestic wastewaters codigestion was determined by laboratory Bach Tests at $35^{\circ}C$ over a period of 90 d using a wide range of leachates volumetric ratios from 0% to 100%. To simulate wastewaters plant treatment step, all the ratios were first air stripped for 48 h before anaerobic incubation. The kinetic of biogas production was assessed using modified Gompertz model and exponential equation. The results obtained showed that cumulative biogas production was insignificant in the case of wastewaters monodigestion while the codigestion significantly improves the BMP. Air stripping pretreatment had positive effect on both ammonium concentration and volatiles fatty acids with reduction up to 75% and 42%, respectively. According to the Modified Gompertz model, the optimal anaerobic co-digestion conditions both in terms of maximal biogas potential, start-up period and maximum daily biogas production rate, could be achieved within large leachate volumetric ratios from 25% to 75% with a maximum BMP value of 438.42 mL/g volatile solid at 50% leachate ratio. The positive effect of codigestion was attributed to a dilution effect of chemical oxygen demand and volatile fatty acid concentrations to optimal range that was between 11.7 to $32.3gO_2/L$ and 2.1 to 7.4 g/L, respectively. These results suggested that the treatment of fresh leachate by their dilution and co digestion at wastewaters treatment plants could be a promising alternative for both energetic and treatment purposes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.2
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• pp.107-116
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• 2006

Purpose:Maxillay sinus grafting is an effective treatment procedure to improve bone height in the posterior maxillar area for implant installation. Beta-tricalciumphosphate(${\beta}$-TCP) was introduced to be grafting substitute material, providing a reasonable bio-degradation time, no need for harvesting procedure. The purpose of this study is to evaluate bone healing & regeneration phase using histomorphometric and immunohistochemical analysis. Material & Methods:Sixteen rabbits were divided into 4 groups. Bi-lateral maxillary sinus membranes were elevated at each rabbits, ${\beta}$-TCP was augmented in left sinus, autogenous bone was augmented in right sinus. The rabbits were sacrificed at 2, 4, 8 and 12 weeks. We investigated the bone regeneration & growth factor expression. Results: 1. The mean new bone volume formation was 28.99${\pm}$6.55%, 49.54${\pm}$5.47%, 69.09${\pm}$8.90% in autogenous grafted area, and 22.86${\pm}$5.56%, 24.00${\pm}$4.09%, 34.11${\pm}$3.37% in ${\beta}$-TCP area at 4, 8, 12 weeks. Therefore, new bone formation in autogenous bone was significantly higher than ${\beta}$-TCP (p<0.05). 2. The BMP 2/4 expression in autogenous bone grafted area was higher at 4, 8 weeks. 3. There was no difference in expression pattern of BMP-7/PDGF/VEGF during grafted bone regeneration. Conclusion:The authors we conclude that the autogenous bone graft was faster than ${\beta}$-TCP in bone regeneration, and the BMP 2/4 were more important in graft bone regeneration.

• Clean Technology
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• v.16 no.1
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• pp.51-58
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• 2010

Methane was produced from the anaerobic digestion of marine macro-algae. Elemental analysis was first performed to estimate the theoretical methane production of three macro-algae (Undaria pinnatifida, Laminaria japonica, Hizikia fusiformis). Three algae were found to contain C 34 ~ 36%, H 5%, O 37 ~ 43%, N 2 ~ 4%, S 0.4 ~ 0.7%, and ash 14~21%, and the theoretical methane content was in the range of 56 ~ 60%, which can produce 442 ~ 568 mL $CH_4$ per g of volatile solid (VS). Using the biological methane potential (BMP) test, we found that L. japonica resulted in the highest yield of methane (52%). Moreover, various operational conditions, such as algae amount, pH, salinity, particle size, and pre-treatment, were investigated in order to find an optimal condition of anaerobic digestion. At pH 8.0, the autoclaved L. japonica (5g VS/200 mL), when used without washing salt, produced 268.5 mL/g VS which is 65% of the theoretical methane productions. Furthermore, using a CSTR (with the working volume of 7 L out of the total volume of 10 L), we have successfully operated the reactor for 65 days and obtained maximum methane production rate of 1.4 L/day with purity of 70%.

• Journal of Microbiology and Biotechnology
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• v.19 no.7
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• pp.713-717
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• 2009

The dependence of the catalytic properties of horseradish peroxidase on the structural changes of ionic liquids was investigated with two water-miscible ionic liquids, N-butyl-3methypyridinium tetraftuoroborate ([$BMP_y$][$BF_4$]) and 1-butyl-3-methylimidazolium methylsulfate ([BMIM][$MeSO_4$]), each of which shares an anion ($BF_4^-$) or a cation ($BMIM^+$) with 1-butyl-3-methylimidazolium tetraftuoroborate ([BMIM][$BF_4$]), respectively. The oxidation of guaiacol (2-methoxyphenol) with $H_2O_2$was used as a model reaction. In order to minimize the effect of solution viscosity on the kinetic constants of the enzymatic catalysis, the enzymatic reactions for the kinetic study were performed in water-ionic liquid mixtures containing 25% (v/v) ionic liquid at maximum. Similarly to the previously reported results for [BMIM][$BF_4$], as the concentration of [$BMP_y$][$BF_4$] increased, the $K_m$value increased with a decrease in the $k_{cat}$value: the $K_m$value increased markedly from 2.8 mM in 100% water to 12.6 mM in 25% (v/v) ionic liquid, indicating that ionic liquid significantly weakens the binding affinity of guaiacol to the enzyme. On the contrary, [BMIM][$MeSO_4$] decreased the Km value to 1.4 mM in 25% (v/v) ionic liquid. [BMIM][$MeSO_4$] also decreased $k_{cat}$more than 3-folds [from 13.8 $s^{-1}$in 100% water to 4.1 $s^{-1}$in 25% (v/v) ionic liquid]. These results indicate that the ionic liquids interact with the enzyme at the molecular level as well as at a macroscopic thermodynamic scale. Specifically, the anionic component of the ionic liquids influenced the catalysis of horseradish peroxidase in different ways.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.5
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• pp.417-433
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• 2006

Purpose : Platelet rich plasma (PRP) is an autologous material with many growth factors, such as BMPs, PDGF, $TGF-{\beta}_1$, $TGF-{\beta}_2$, VEGF, and IGF, facilitating bone healing process. The prominent osteoconductive activity and the biodegradable nature of beta-tricalciumphosphate (${\beta}-TCP$) for bone grafts in animal experiments have been reported. The purpose of this study was to evaluate the effect of PRP on the osteogenesis of ${\beta}-TCP$. Materials & Methods : Two artificial calvarial bone defects were made in 32 rabbits which were divided into 2 groups. In one group of 16 rabbits, autogenous bone / ${\beta}-TCP$ was grafted on each side of cranial bone defect. In the other group of 16 rabbits, mixture of ${\beta}-TCP$ and PRP / PRP alone was grafted on each side of the cranial bone defect. The animals were sacrificed at 2, 4, 8, and 12 weeks after surgery. The specimens were harvested and examined histologically and immunohistochemically by the expression of BMP2/4/7, PDGF, VEGF and $TGF-{\beta}_1$. Results : The mean volume of new bone formation was significantly higher at 4, 8, 12 weeks in autogenous graft than that in ${\beta}-TCP$. The BMP2/4 expression was significantly higher at 4 weeks in autogenous bone graft and at 4 weeks in mixture of ${\beta}-TCP$ and PRP and at 12 weeks in ${\beta}-TCP$. The expression of BMP7, PDGF, VEGF and $TGF-{\beta}_1$ showed no significant difference in autogenous, ${\beta}-TCP$, mixture of ${\beta}-TCP$ and PRP, and PRP alone during grafted bone regeneration. Conclusion : The results showed that PRP had no additional value in promoting healing process of ${\beta}-TCP$ grafts.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.4
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• pp.360-373
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• 2006

The purpose of this research was to investigate whether pulsed electromagnetic field (PEMF) stimulation applied to the rabbit cranial defects grafted with ${\beta}$-tricalcium phosphate (${\beta}$-TCP) could affect the new bone formation. With 16 New Zealand white rabbits under the same condition, bilateral calvarial bone defects were formed around the sagittal suture line. The defect on the left side was grafted with ${\beta}$-TCP, while on the right side was grafted by harvested autogenous bone. PEMF was applied to 8 rabbits for 8 hours per day. The bony specimen were divided into 3 groups, the group 1 was autogenous bone grafted specimen, the group 2 was ${\beta}$-TCP grafted with PEMF, and the group 3 was ${\beta}$-TCP grafted without PEMF. We investigated the bone regeneration & growth factor expression at 2, 4, 6, and 8 weeks. As a result, BMP 2 was expressed in the group 1 from 2 weeks, the group 2 from 4 weeks, and the group 3 from 6 weeks. BMP 4 was expressed in the group 1 from 2 weeks, in the group 2 and the group 3 from 4 weeks. 4. There was no significant difference in expression pattern of BMP 7, PDGF, VEGF, and TGF-${\beta}$1 during grafted bone regeneration in group 1, 2, and 3. According to our results, PEMF stimulation could be effective on the new bome formation in animal study, and have a feasibility of clinical use.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.588-597
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• 2016

In this study, we attempted to improve the biogas production efficiency by varying the mixing ratio of the mixed sludge of organic wastes in the improved single-phase anaerobic digestion process. The types of organic waste used in this study were raw sewage sludge, food wastewater leachate and livestock excretions. The biomethane potential was determined through the BMP test. The results showed that the biomethane potential of the livestock excretions was the highest at $1.55m^3CN4/kgVS$, and that the highest value of the composite sample, containing primary sludge, food waste leachate and livestock excretions at proportions of 50%, 30% and 20% respectively) was $0.43m^3CN4/kgVS$. On the other hand, the optimal mixture ratio of composite sludge in the demonstration plant was 68.5 (raw sludge) : 18.0 (food waste leachate) : 13.5 (livestock excretions), which was a somewhat different result from that obtained in the BMP test. This difference was attributed to the changes in the composite sludge properties and digester operating conditions, such as the retention time. The amount of biogas produced in the single-phase anaerobic digestion process was $2,514m^3/d$ with a methane content of 62.8%. Considering the value of $2,319m^3/d$ of biogas produced as its design capacity, it was considered that this process demonstrated the maximum capacity. Also, through this study, it was shown that, in the case of the anaerobic digestion process, the two-phase digestion process is better in terms of its stable tank operation and high efficiency, whereas the existing single-phase digestion process allows for the improvement of the digestion efficiency and performance.

• The korean journal of orthodontics
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• v.34 no.2 s.103
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• pp.143-152
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• 2004

It has not been elucidated whether the initiation of condylar development of the mandible is related with the periosteum of the mandible, or if it derives from a separate programmed blastema not related with the mandible. Also, although the mandibular condylar cartilage is known to promote growth, few studies have dealt with molecular-biologic mechanisms such as the expression of specific genes according to the differentiation of the mandibular condyle. To elucidate the unique cellular characteristics, development, and differentiation process of the mandibular condyle, an examination of expressions of genes characteristic of cartilage and bone were carried out using RT-PCR and mRNA in situ hybridization. 1. Type? collagen mRNA was detected with type II collagen mRNA in the differentiation and growth process of the cartilage of the mandibular condyle. TypeII collagen mRNA was demonstrated in the whole resting md upper part of the poliferative zone, whereas type II collagen mRNA was observed in the resting, proliferative and upper hypertrophic cartilage zone of the mandibular condyle. 2. The condylar cartilage rapidly increased in size due to the accumulation of hypertrophic chondrocytes as characterized by the expression of type II collagen mRNA during postnatal development. 3. BMP-4 mRNA was present in the anlage of the future condylar process and also in the ossifying mandibular body. 4. IHH mRNA was limited exclusively to the lower part of the proliferative zone and the upper part of the hypertrophic cartilage zone during condylar development. These findings were different from those in the growth-plate cartilage of the long bone, indicating a characteristic feature of the differentiation of the chondrocytes in the condylar cartilage present in prenatal and postnatal development. Furthermore, it was also suggested that chondroblasts of condylar cartilage rapidly differentiate into hypertrophic chondrocytes with increased functional Load force such as muscle activity and mastication.

• New & Renewable Energy
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• v.4 no.4
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• pp.56-64
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• 2008

Anaerobic biodegradability (AB), which can be determined with the ultimate methane yield by the decomposition of organic materials, is one of the important parameters for the design and the operation of anaerobic digestion plant. In this study, Biochemical methane potential (BMP) test has been carried out to evaluate the methane yields of animal manures such as pig and cattle slurries, and different forage crops cultivated at the reclaimed tideland such as maize, sorghum, barley, rye, Italian ryegrass (IRG), rape, rush, and waste sludge produced from slaughterhouse wastewater treatment plant (SSWTP). In the ultimate methane yield and biodegradability of animal manure, those of pig slurry were 345 $mlCH_4/gVS_{fed}$ and 44.7% higher than 247 $mlCH_4/gVS_{fed}$ and 46.4% of cattle slurry (Cat. 2). The ultimate methane yield and biodegradability of spike-crop rye (Rye 1) were 442.36 $mlCH_4/gVS_{fed}$ and 86.5% the highest among different forage crops, those of the other forage crops ranged from 306.6 to 379 $mlCH_4/gVS_{fed}$ of methane yield with the AB having the range of about 60 to 77%. Therefore the forage crops could be used as a good substrate to increase the methane production and to improve the biodegradability in anaerobic co-digestion together with animal manure.

• Journal of Energy Engineering
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• v.23 no.1
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• pp.33-39
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• 2014

This study was performed with electrolysis treatment method for improving anaerobic digestion gas production efficiency in a sewage sludge, thereby confirmed in anaerobic digestion production and denitrification effect. As a result, solubilization was increased by increasing treatment time of electrolysis and current density, also showed to be 9.02% with 10 mA/cm2 of current density in 4 mm electrode distance. Based on the results of BMP test used the above experiment, methane production was 0.49 L CH4/g VS, and increased by 88.4% compared with control groups. As for the results of denitrification using the sewage sludge treated with the same conditions, denitrification rate appeared $19.2mg\;NO_3{^{-}}N/g\;MLVSS{\cdot}hr$, and through the sewage sludge treated with electrolysis, it can be applied to anaerobic digestion and denitrification process by increasing biodegradation.