• KSBB Journal
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• v.30 no.6
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• pp.332-338
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• 2015

The objective of this study was designed to determine the possibility of bioethanol production from wasted medium density fiberboard (wMDF). We were investigated the enzymatic saccharification characteristics using the enzyme (Cellic CTec3) after pretreatment with sodium chlorite. According to the component analysis results, the lignin contents before and after the pretreatment of wMDF (milling using sieve size of $1,000{\mu}m$) was significantly reduced from 31.13% to 4.11%. Therefore, delignification ratio of pretreated wMDF was found to be up to about 87-89% depending on the sieve size. And we were tested to compare the saccharification ratio according to the sieve size of wMDF ($1,000{\mu}m$, $200{\mu}m$), but it was no significance depending on the sieve size. When enzyme dosage was 5% based on the substrate concentration, enzymatic saccharification ratio was obtained up to 70% by maintaining at $50^{\circ}C$ for 72 hours. We could made the substrate concentration of pretreated wMDF ($1,000{\mu}m$) up to 12% and then enzymatic saccharification ratio was 76.8%, also contents of glucose and xylose were analyzed to 77,750 and 14,637 mg/L, respectively.

• Korean Journal of Materials Research
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• v.26 no.3
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• pp.109-116
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• 2016

To achieve the fabrication of high-quality Ag-coated Cu particles through a wet chemical process, we reported herein pretreatment conditions using an ammonium-based mixed solvent for the removal of a $Cu_2O$ layer on Cu particles that were oxidized in air for 1 hr at $200^{\circ}C$ or for 3 days at room temperature. Furthermore, we discussed the results of post-Ag plating with respect to removal level of the oxide layer. X-ray diffraction results revealed that the removal rate of the oxide layer is directly proportional to the concentration of the pretreatment solvent. With the results of Auger electron spectroscopy using oxidized Cu plates, the concentrations required to completely remove 50-nm-thick and 2-nm-thick oxides within 5 min were determined to be X2.5 and X0.13. However, the optimal concentrations in an actual Ag plating process using Cu powder increased to X0.4 and X0.5, respectively, because the oxidation in powder may be accelerated and the complete removal of oxide should be tuned to the thickest oxide layer among all the particles. Back-scattered electron images showed the formation of pure fine Ag particles instead of a uniform and smooth Ag coating in the Ag plating performed after incomplete removal of the oxide layer, indicating that the remaining oxide layer obstructs heterogeneous nucleation and plating by reduced Ag atoms.

• Journal of Periodontal and Implant Science
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• v.42 no.3
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• pp.95-104
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• 2012

Purpose: The purpose of this study was to determine whether increasing the Ti6Al4V surface oxide negative charge through heat ($600^{\circ}C$) or radiofrequency plasma glow discharge (RFGD) pretreatment, with or without a subsequent coating with fibronectin, stimulated osteoblast gene marker expression in the MC3T3 osteoprogenitor cell line. Methods: Quantitative real-time polymerase chain reaction was used to measure changes over time in the mRNA levels for osteoblast gene markers, including alkaline phosphatase, bone sialoprotein, collagen type I (${\alpha}1$), osteocalcin, osteopontin and parathyroid hormone-related peptide (PTH-rP), and the osteoblast precursor genes Runx2 and osterix. Results: Osteoprogenitors began to differentiate earlier on disks that were pretreated with heat or RFGD. The pretreatments increased gene marker expression in the absence of a fibronectin coating. However, pretreatments increased osteoblast gene expression for fibronectin-coated disks more than uncoated disks, suggesting a surface oxide-mediated specific enhancement of fibronectin's bioactivity. Heat pretreatment had greater effects on the mRNA expression of genes for PTH-rP, alkaline phosphatase and osteocalcin while RFGD pretreatment had greater effects on osteopontin and bone sialoprotein gene expression. Conclusions: The results suggest that heat and RFGD pretreatments of the Ti6Al4V surface oxide stimulated osteoblast differentiation through an enhancement of (a) coated fibronectin's bioactivity and (b) the bioactivities of other serum or matrix proteins. The quantitative differences in the effects of the two pretreatments on osteoblast gene marker expression may have arisen from the unique physico-chemical characteristics of each resultant oxide surface. Therefore, engineering the Ti6Al4V surface oxide to become more negatively charged can be used to accelerate osteoblast differentiation through fibronectin-dependent and independent mechanisms.

• Horticultural Science & Technology
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• v.17 no.2
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• pp.138-140
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• 1999

These studies were carried out to investigate the effects of cold pretreatment, dark condition, and Ficoll on the callus formation and organ differentiation in anther culture of carnation for the purpose of settling the techniques of anther culture of 'Rony' carnation. Diameter of flower buds containing anthers with microspores before or after uniuncleated stage was between 4 and 6 mm. A high percentage of callus formation and responding anthers were achieved by low temperature pretreatment at $4^{\circ}C$ for 7 days. Callus formation was promoted under dark condition. Roots were differentiated from calli formed under darkness. Ficoll didn't promote callus formation but promoted differentiation of shoots and roots.

• Food Science and Preservation
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• v.5 no.4
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• pp.320-325
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• 1998

Effects of blanching and salting for the pretreatment during frozen storage condition were investigated and optimized the salting condition on the activities of peroxidase and lipoxygenase, the stability of vitamin C and color, moisture content and hardness in immatured soybean. Before frozen storage, pretreatment processing is necessary to extend the shelf-life of vegetables. Salting condition of 2% for 180min treatment led to maximum inactivation of both lipoxygenase and peroxidase while blanching can more inactivate for lipoxygenase. Salting at 2% for 180min resulted in the highest amount of vitamin C remaining in the immatured soybeans after 6 months storage. The color of the immatured soybeans were severely changed after 6 months storage, while the color of salted soybeans at 3% and 180min treatment was similar to fresh products. Moisture content and hardness were reduced with addition of salt.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.751-754
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• 2008

Texture analysis, sensory evaluation, and scanning electronic microscopic (SEM) observation were conducted to evaluate the effects of different calcium salts (calcium lactate, calcium acetate, and calcium chloride) and vitamin C on the textural properties of kimchi, gamma-irradiated at 25 kGy. Increase of the hardness and sensory score were observed in the kimchi pretreated with calcium salt or vitamin C as compared with the untreated and irradiated kimchi. And the hardness and sensory quality of the co-pretreated sample with 0.01% of calcium lactate and 0.3% of vitamin C were the highest after 30 days at $35^{\circ}C$, which indicates that the co-pretreatment is effective in preventing a decrease of the texture and sensory qualities of kimchi by gamma irradiation. Also, this result was supported by the SEM observation.

• Korean Journal of Food Science and Technology
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• v.48 no.6
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• pp.565-568
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• 2016

This study was conducted to soften the tough texture of retorted beef in storage by increasing the water holding capacity (WHC) after pretreatment involving soaking and blanching in a phosphate solution. The yield of pretreated beef, based on weight as an indirect indicator of WHC, soaked in 0.35% (w/w) complex phosphates for 1 h, increased by 5-10%, in contrast to the untreated control in which the rib and shank was heated at $100^{\circ}C$ for 5-40 min. Additionally, strength of mechanical toughness in the fore rump and rib after phosphate curing at $115^{\circ}C$ for 30 min and blanching at $100^{\circ}C$ for 2 min were significantly decreased to 1.3 and $1.4kg_f$ (p<0.05) as compared to 2.0 and $1.8kg_f$ in the control, respectively. During storage of retorted beef for 30 days at $10^{\circ}C$, rib and shank pretreated with 0.35% complex phosphates exhibited a highly soft texture as compared to that of untreated beef. The softening of pretreated beef was based on the increased WHC due to complex phosphates.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.4
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• pp.383-391
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• 1999

This study was carried out to determine whether the effects of an ${\alpha}_2-adrenoceptor$ agonist, clonidine, on mean arterial pressure (MAP) and heart rate (HR) are influenced by mild hypothermia. Experiments were performed in respiration-controlled and spontaneously breathing pentobarbital-anesthetized rats. Rectal temperature was maintained at $37.5{\pm}0.3^{circ}C$ for normothermic groups or at $35.2{\pm}0.3^{circ}C$ for mild hypothermic groups. Intravenous injection of clonidine (1 and 2 ${\mu}g/kg)$ produced depressor and bradycardic responses in spontaneously breathing rats under both normothermic and mild hypothermic condition: a decrease in MAP was not altered but bradycardic response was significantly augmented in the mild hypothermic group as compared with the normothermic group. Under the respiration-controlled condition, the hypotensive effect of clonidine $(2\;{\mu}g/kg)$ was reduced, whereas the bradycardic effect was increased in mild hypothermic rats as compared with normothermic rats. Both hypotensive and bradycardic effects of clondine $(2\;{\mu}g/kg)$ were blocked by pretreatment with an ${\alpha}_2-adrenoceptor$ antagonist, yohimbine (0.5 mg/kg), in both thermal conditions. Yohimbine (0.5 mg/kg, i.v.) alone produced signifcantly an increase in heart rate in the mild hypothermic group than in the normothermic group. Pretreatment with a muscarinic receptor antagonist, atropine methylnitrate (1 mg/kg, i.v.), attenuated the bradycardic effect of clonidine in the mild hypothermic group but not in the normothermic group. These results suggest that clonidine- induced bradycardia is amplified by mild hypothermia probably through an increased parasympathetic activity.

• Food Science and Preservation
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• v.12 no.4
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• pp.305-309
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• 2005

To investigate the effects of cinnamon extracts pretreatment and packaging on the quality of dried persimmon. Dried persimmon were storaged during 100 days at room temperature($15^{\circ}C$) after dipping in cinnamon extracts and then packaging with LDPE(low density polyethylene) and Nylon/LDPE pouch Weight loss of dried persimmon treated with K-V was maintained $20.2\%$ lower than control. Firmness was $87\%$, browning was $56\%$ lower. Skin color change was 0.80 point, which was the lowest changes comparing with others. As a result, dipping in cinnamon extracts and packaging Nylon/LDPE film were good for maintaining dried qualities.

• Preventive Nutrition and Food Science
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• v.11 no.4
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• pp.318-322
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• 2006

The objective of this experiment was to investigate the effect of extrusion of ginseng roots in twin screw extruder on susceptibility of ginseng starch toward hydrolysis by ${\alpha}-amylase$ BAN 480L (Novozyme, Denmark) and cellulase Celluclast 150L and saccharification by amyloglucosidase AMG-E (Novozyme, Denmark). The extrusion was conducted at 22% and 30% moisture contents of feed at screw speed 300 rpm. Barrel temperature at zone 1 was adjusted at $100^{\circ}C$ and $120^{\circ}C$. The results showed that extrusion process improved the ginseng ${\alpha}-amylase$ susceptibility as compared to traditionally dried ginseng (white and red ginseng). Reducing sugar of hydrolyzed extruded samples was 2,500% of its initial concentration, whereas the reducing sugar of hydrolyzed non-extruded sample was only 200% of its initial concentration. However, addition of cellulase during liquefaction lowered the saccharification yield of both non-extruded and extruded samples as well.