• Polymer(Korea)
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• v.28 no.5
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• pp.404-411
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• 2004

The microcapsules containing triphenyl phosphate (TPP), a flame retardant, were prepared by phase-inversion emulsification technique using the epoxy resin (Novolac type) with excellent physical properties and network structure. This microencapsulation process was adopted for the protection of TPP evaporation and wetting of polymer composite during the polymer blend processing. The TPP, epoxy resin and mixed surfactants were emulsified to oil in water (O/W) by the phase inversion technology and then conducted on the crosslinking of epoxy resin by in-situ polymerization. The capsule size and size distribution of TPP capsules was controlled by mixed surfactant ratio, concentration and TPP contents, The formation and thermal property of TPP capsules were measured by differential scanning calorimetry and thermogravimetric analysis. The morphology and size of TPP capsules were also investigated by scanning and transmission electron microscopies. As the surfactant concentration increased, the TPP capsules were more spherical and mono-dispersed at the same weight ratio of mixed surfactants (F127: SDBS).

• Polymer(Korea)
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• v.33 no.1
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• pp.26-32
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• 2009

The aim of this research was to prepare microparticulate systems based on poly (lactide-co-glycolide)(PLGA) for the local release of ipriflavone in order to reduce bone loss. We developed the IP loaded PLGA microspheres using relatively simple oil-in-water(O/W) solvent evaporation method. HPLC was used to perform the in vitro release test of IP and morphology of cell attached on the micro-spheres was investigated using SEM. Cytotoxicity was assayed by cell counting kit-8 (CCK-8) test. Osteogenic differential cells were analyzed by ALP activity. Through RT-PCR analysis, we observed osteocalcin, ALP, and Type I collagen mRNA expression. The release of IP in vitro was more prolonged over 42 days and IP/PLGA microspheres showed the improvement on the cell proliferation, ALP activity and RT-PCR comparing with control (only PLGA). This initial research will be used to direct future work involved in developing this composite injectable bone tissue engineering system.

• The Journal of Korean Obstetrics and Gynecology
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• v.24 no.2
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• pp.52-67
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• 2011

Objectives: This study was designed to investigate the effects of Jokyeongjongok -Tang(JJT) on the progression of the estradiol valerate(EV)-induced polycystic ovaries(PCO) in rats. Methods: PCO was induced by single intramuscular injection with estradiol valerate(EV)(4 mg) in female rats. Normal group(n=8) were injected with sesame oil and orally administrated distilled water for sixty days. PCO control group (n=8) were injected with EV and orally administrated distilled water for sixty days. JJT treated group(n=8) were injected with EV and orally administrated JJT for same duration. At the end day of experiment, we measured weights of body, ovaries, adrenal glands and uterus. The histopathological changes of ovaries were also evaluated. And we observed the NGF and CRF expression by immunohistochemistry. Results: The results were as follows - The weights(mg) of ovaries of JJT treated group($58.4{\pm}9.4$) were significantly increased(p<0.01) compared with PCO control group($42.3{\pm}8.5$). - The numbers of mature follicles of JJT treated group($10.1{\pm}2.5$) were significantly increased(p<0.01) compared with PCO control group($6.1{\pm}2.1$). - The numbers of cystic follicles of JJT treated group($1.8{\pm}1.4$) were significantly decreased(p<0.05) compared with PCO control group($3.8{\pm}1.5$). - The expressions of NGF-immunoreactive cells in the ovaries of JJT treated group were weaker than PCO control group. Conclusions: From the above results, we concluded that Jokyeongjongok-Tang (JJT) contributes to a normal maturation of follicles and has the effects of promoting a normal ovulation. And these effects may be related with the decreased NGF activities in the ovaries.

• The Journal of Korean Obstetrics and Gynecology
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• v.25 no.2
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• pp.43-65
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• 2012

Objectives: This study was designed to investigate the effects of Hyeolbuchukeotang( HCT) on the Estradiol Valerate(EV) induced Polycystic Ovaries and the Implantation of rats. Methods: PCO was induced by single intramuscular(IM) injection with EV in female rats. Normal group(n=8) were injected with sesame oil and orally administrated distilled water for 60 days. Control group(n=8) were injected with EV and orally administrated distilled water for 60 days. HCT treated group(n=8) were injected with EV and orally administrated HCT for 60 days. At the end day of experiment, we measured weights of body, ovaries, adrenal glands, uterus and contents of serum LH, FSH, ADD. The histomorphometrical changes of ovaries were also evaluated. And we observed the NGF and CRF expression by immunohistochemistry. Also we observed the mating and count the number of implantation. Results: - The weights(mg) of ovaries in HCT treated group($58.9{\pm}6.5$) were significantly increased (p<0.01) compared with control group ($42.3{\pm}8.5$). - The number of mature follicles in HCT treated group($9.8{\pm}2.6$) was significantly increased (p<0.01) compared with control group($6.1{\pm}2.1$). - The number of cystic follicles in HCT treated group($1.6{\pm}1.2$) was significantly decreased (p<0.01) compared with control group($3.8{\pm}1.5$). - The value of serum FSH(mIU/ml) in HCT treated group($3.870{\pm}2.151$) was significantly decreased(p<0.05) compared with control group($10.476{\pm}6.294$). - The expression of NGF-immunoreactive cells in the ovarian cells in HCT treated group was lesser observed than control group. - The number of implantation in HCT treated group($7.4{\pm}1.8$) was significantly increased (p<0.05) compared with control group($3.1{\pm}4.4$). Conclusions: Hyeolbuchukeo-tang(HCT) is effect on polycystic ovaries and the implantation of rats by EV-induced.

• Korean Journal of Pharmacognosy
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• v.41 no.3
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• pp.216-220
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• 2010

Obesity is an important risk factor that significantly increases mortality and disease rates in the cardiovascular disease, diabetes, and various diseases. So far, the most powerful way to inhibit fat absorption is pancreatic lipase inhibitors. In this study, we investigated the anti-obesity effect of the extract of Juniperus rigida. Juniperus rigida extract (JRE) had a inhibitory effect on pancreatic lipase activity ($IC_{50}$=8.63 ${\mu}g$/ml). In in vivo oil-emulsion loading test, this extract also inhibited the intestinal fat absorption. In addition, we measured inhibitory effects of JRE on activity of phosphodiesterase (PDE) and hormone sensitive lipase (HSL) among the important enzymes associated with lipolysis. JRE strongly inhibited PDE activity ($IC_{50}$=4.56 ${\mu}g$/ml), whereas inhibitory effect on HSL activity was very weak compared with orlistat. As a result, JRE inhibited the absorption of fat by inhibiting the activity of pancreatic lipase and induced lipolysis through inhibition of PDE activity. Therefore, we suggest that Juniperus rigida may be a potential therapeutic agent improving obesity.

• Korean Journal of Poultry Science
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• v.32 no.4
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• pp.255-260
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• 2005

This study was conducted to evaluate the feasibility of spent bleaching clay(SBC) as an energy resource for meat type chicks. A total of one hundred twenty 1-d old broiler chicks(Han-hyop, No. 3) were divided into four groups and each group was assigned to one of the following diets: 0(T1), 2.0(T2), 4.0(T3) and $6.0\%$ SBC(T4). Each treatment had 3 replications of 10 birds. Before feeding experimental diets, they were fed a commercial diet for a week Body weight gain and feed intake tended to increase in T3 and T4, respectively. Feed efficiency(feed intake/ gain) tended to decrease in T3 compared to other groups. Fatty acid composition of breast and thigh meat was not significantly affected by feeding SBC. Utilization of dry matter, energy, crude protein and crude fat was lower in T4 than in the other groups during both starter and finisher periods(p<0.05). Crude ash utilization was not significantly affected by feeding dietary SBC. These results indicate that broiler diets may be supplemented with 2 to $4\%$ SBC without adverse effect on growth.

• Korean Journal of Poultry Science
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• v.20 no.4
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• pp.217-231
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• 1993

Due to the increased awareness on the relationship between high cholesterol intake and cardiovascular disease, the development of low cholesterol eggs and egg products are necessary at the present time. Largely, two approaches are possible to develop low cholesterol eggs. The first approach is the production of low cholesterol eggs by altering feeds of layers, by administering drugs, by genetic selection of strains and breeds, and by management of laying cycle, age and egg size. The second approach is to manufacture low cholesterol eggs technically treated with adsorbant, solvent, enzyme, edible oil and supercritical fluid. Both approaches have their own pros and cons, respectively, as far as the cholesterol removal rates, the easeness of process, and the economic reasons are concerned. The low cholesterol egg production is quite labor-intensive and has relatively low cholesterol removal rate(30∼50％ ) compared to that of chemically treated eggs. On the other hand, the low cholesterol eggs treated with chemicals have a very high cholesterol removal rate (80∼90％) but some of the methods are not completely safe as food processing purposes due to the residual chemicals and the sensory quality is not as good as the low cholesterol eggs without chemical treatment. Therefore, further studies must be conducted to improve the sensory quality of low cholesterol eggs and to eliminate fear about the harmfulness using low cholesterol eggs.

• Korean Journal of Medicinal Crop Science
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• v.18 no.5
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• pp.323-328
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• 2010

Root extract of Lythrum salicaria reported a hepato-protective effect on $CCl_4$-induced liver toxicity of rat was prepared into fractions such as n-hexane up layer (HA), n-hexane down layer (HB), diethyl ether (E), ethylacetate (EA), n-butanol (B) and water (W). Fractions prepared were tested their activities in vitro and in vivo condition. All of the fractions showed effective antioxidant asctivities on DPPH radical and $CuSO_4$-induced oxidation of human low density lipoprotein and E fraction showed the highest inhibitory effect (98.1% at $50\;{\mu}g/m{\ell}$) on linoleic acid autoxidation at $40^{\circ}C$, which was more effective than $\alpha$-tocopherol (82.4%). Five fractions (H = HA plus HB, E, EA, B, and W, 150 mg/kg/day) were fed into Sprague Dawley, male rats for 4 days, which were intoxicated with intra-peritoneal injection of carbon tetrachloride ($1\;m{\ell}/kg$ in corn oil) at the 4th day and were sacrificed in 24 hrs. Serum tumor necrosis factor-alpha (TNF-$\alpha$), a proinflammatory cytokine, elevated with $CCl_4$-intoxication in negative control group ($83\;pg/m{\ell}$) was significantly decreased in E fraction-supplemented group ($18\;pg/m{\ell}$). Cu, Zn-superoxide dismutase (SOD) activity increased in negative control group (0.12 U/mg protein) was decreased in E fraction (0.07 U/mg protein). From the results, it is suggested that ether fraction from root extract of L. salicaria would be a potent antioxidant candidate for ameliorating liver injury induced by chemical intoxicant.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.06a
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• pp.162-177
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• 2001

The hydrolysis rates of seven kinds of polyol ester base oils 〔POEs〕 of different branch shape were investigated by using a simple apparatus under mild acidic condition. Seven polyol ester base oils were made of poly hydric alcohols of two-four valence, normal or branched fatty acids of different carbon number. p-Toluene sulfonic acid was used as acid catalyst to accelerate the rate of hydrolysis. Partial esters and fatty acid produced by sequential hydrolysis of POEs were identified and their concentrations were determined by calibrated-internal standard method using Gas Chromatography. The rate constants of each step in sequential hydrolysis were determined by the least square method from rate equation and the concentration of each component, were compared with one another. It was shown that the rate of hydrolysis of POEs was strongly affected by whether molecular structure of fatty acid was straight chain or branch chain and which position was branched. The hydrolysis stability for all the POEs can be reasonably explained by using a steric hindrance effect anticipated fi:om their molecular structures affecting as water molecule makes an attack on the carbonyl carbon of POEs.

• Journal of Korean Society of Transportation
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• v.28 no.5
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• pp.91-106
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• 2010

Recently, interest in supply chain management is rising along with the increasing oil prices and traffic congestion. In particular, people started studying the issue, but realized that advantageous strategies for suppliers and retailers are not always advantageous to a carrier. Therefore, in this study the atuhors set up a simulation scenario to understand delivery vehicle routing problems under various inventory policies, namely Economic Order Quantity (EOQ) and Periodic Order Quantity (POQ) and network configurations. First, the authors made a virtual supply chain. Then they analyzed characteristics of delivery vehicle routing under various inventory policies (EOQ and POQ) and network configurations. As a result, the POQ inventory policy decreases the number of vehicles, the number of drivers, and the service time of vehicles. Also, the centralized network increases the load factor of vehicles and decreases the service time of vehicles. In other words, the centralized network and the POQ inventory policy are better for the carrier. These results show a savings of 15,556,806 won ($13,389.10) in a month: a reduction of 17%.