• Bulletin of the Korean Chemical Society
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• v.17 no.6
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• pp.520-524
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• 1996

Solvolyses of phenyl chloroformate in water, D2O, CH3OD, 50% D2O-CH3OD, and in aqueous binary mixtures of acetone, ethanol and methanol are investigated at 25.0 ℃. Product selectivities are reported at 25 ℃ for a wide range of ethanol-water and methanol-water solvent compositions. The Grunwald-Winstein plots of first-order rate constants for phenyl chloroformate with YCl (based on 2-adamantyl chloride) show marked dispersions into three separate lines for the three aqueous mixtures with a small m value (m< 0.2) and a rate maximum for aqueous alcohol solvents. Third-order rate constants, kww, kaw, kwa and kaa were calculated from the observed kww and kaa values together with kaw and kwa calculated from the intercept and slope of the plot of 1/S vs. [alcohol]/[water]. The calculated rate constants, kcalc and mol % of ester agree satisfactorily with those of the observed rate constants, kobs and mol % of ester, supporting the stoichiometric solvation effect analysis. The kinetic solvent isotope effects determined in water and methanol are consistent with the proposed mechanism of the general base catalyzed and/or carbonyl addition for phenyl chloroformate solvolyses based on mass law and stoichiometric solvation effect studies.

• Journal of Periodontal and Implant Science
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• v.36 no.2
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• pp.385-396
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• 2006

For the regeneration of periodontal tissues, the microenvironment for new attachment of connective tissue fibers should be provided, At this point of view, cementum formation in root surface plays a key role for this new attachment. This study was performed to figure out which factor promotes differentiation of cementoblast Considering anatomical structure of tooth, we selected the cells which may affect the differentiation of cementoblast - Ameloblast, OD11&MDPC23 for odontoblasts, NIH3T3 for fibroblsts and MG63 for osteoblasts. And OCCM30 was selected for cementoblast cell line. Then, the cell lines were cultured respectively and transferred the conditioned media to OCCM30. To evaluate the result, Alizarin red S stain was proceeded for evaluation of mineralization. The subjected mRNA genes are bone sialoprotein(BSP), alkaline phosphate(ALP) , osteocalcin(OC), type I collagen(Col I), osteonectin(SPARC ; secreted protein acidic and rich in cysteine). Expression of the gene were analysed by RT-PCR, The results were as follows: 1. For alizarin red S staining, control OCCM30 didn't show any mineralized red nodules until 14 days. But red nodules started to appear from about 4 days in MDPC-OCCM30 & OD11-OCCM30. 2. For results of RT-PCR, ESP mRNAs of control-OCCM30 and others were expressed from 14 days, but in MDPC23-OCCM30 & OD11-OCCM30 from 4 days. Like this, the gene expression of MDPC23-OCCM30 & OD11-OCCM30 were detected much earlier than others. 3. For confirmation of odontoblast effect on cementoblast, conditioned media of osteoblasts(MG63) which is mineralized by producing matrix vesicles didn't affect on the mineralized nodule formation of cementoblasts(OCCM30). This suggest the possibility that cementoblast mineralization is regulated by specific factor in dentin matrix protein rather than matrix vesicles. Therefore, we proved that the dentin/odontoblast promotes differentiation/mineralization of cementoblasts. This new approach might hole promise as diverse possibilities for the regeneration of tissues after periodontal disease.

• Journal of Veterinary Clinics
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• v.40 no.2
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• pp.158-163
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• 2023

A 9-year-old spayed female Shih-Tzu was presented with a mass on the upper eyelid of the right eye (OD). The eyelid mass continued to enlarge along the eyelid margin and the eyelid skin. Throughout the follow-up examinations, the mass did not affect the palpebral conjunctiva OD. Until 9 months since the mass was first identified, the dog did not show any clinical signs related to the mass. However, after 11 months, the owner complained of the dog's discomfort on OD and decided on surgical excision of the mass. There were no abnormalities in the complete blood count and serum chemistry profiles. The pentagonal resection was performed to completely remove the mass in the eyelid. There were no suspicious findings of metastasis on whole-body computed tomography scan immediately before the surgery. On histopathology and immunohistochemistry for multiple myeloma oncogene-1, the eyelid mass was diagnosed as extramedullary plasmacytoma (EMP). Surgical margin of the mass was clearly cut. No recurrence was observed during the 5-month follow-up. EMPs on the eyelid have rarely been reported in dogs. Although EMP is a benign tumor, the mass showed invasive growth and grew toward the skin rather than the palpebral conjunctiva. No recurrence occurred when surgically removed with clean margins.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.2
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• pp.210-217
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• 1999

This paper reports the experimental results on heat transfer characteristics of R-22 and R-407C(HFC-32/125/134a 23/25/52 wt%) condensing inside horizontal smooth and finned tubes. The test condensers used In the study are double pipe heat exchangers of 7.5 mm ID, 9.5 mm OD smooth tube, and 60 finned micro-fin tube with 8.53 mm ID, 9.53 mm OD. Each of these tubes was 4 000 mm long tubes connected with an U-bend. These U type two-path test tubes are divided In 8 local test sections for the identification of the local condensing heat transfer characterisitcs and pressure drop, U-bend effects on condensing flows. Inlet quality is maintained 1.0, and refrigerant mass velocity is varied from 102.0 to $301.0kg/m^2{\cdot}s$. From the results, it was found that the pressure drop of the R-407C Increased, and heat transfer coefficient decreased compared to those of R-22. In comparison condensing heat transfer characteristics of micro-fm tube with those of smooth tube, increasing of condensing heat transfer coefficient was found outstanding compared to the increasing ratio of pressure drop. Furthermore, pressure drop In U-bend showed at most a 30 % compared to the total pressure drop in the test section.

• Reproductive and Developmental Biology
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• v.30 no.1
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• pp.13-19
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• 2006

To search of new porcine pheromonal odorants for biostimulation control system technologies to improve reproductive efficiency in livestock species, the comparative molecular field analysis (CoMFA) for binding affinity constant $(p(Od)_{50})$ between porcine odorant binding protein (pOBP) and ligands of odorant 2-(cyclohexyloxy) tetrahydrofurane derivatives as substrate molecule was conducted and discussed. In the optimized CoMFA model AIV with chirality $(C_1'(R),\;C_2(S))$ in substrate molecule and atom based fit alignment (A) of odorants, the statistical results showed the best predictability of the binding affinities $(p(Od)_{50})$ based on the LOO cross-validated value $r^2_{cv}.\;(q^2=0.886)$ and non-cross-validated conventional coefficient $(r^2_{ncv}.=0.984)$. the binding affinity constants exhibited a good correlation with steric (40.8%), electrostatic (14.6%) and hydrophobic (44.6%) factors of the substrate molecules. from the analytical results of the contour maps, which may give us some valuable informations to the modification of odorants for effective binding affinity.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.3
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• pp.11-21
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• 2015

Emergency Medical Service(EMS) has become focused due to all kinds of disaster and a great number of casualties. The 119 emergency vehicles' dispatching methods are now being focused, for travel time of ambulances are the critical components in terms of saving human lives. Therefore, this study tried to rearrange 119 EMS regions more efficiently. For this study, Daejeon Metropolitan City's real call cases were analyzed. In order to rearrange the regions, OD Cost Matrix analysis was performed between 800 thousands random points and 26 departments in the Daejoen Metropolitan City. By creating Thiessen Polygon from the random points, a new region was created. As a results, average areas of the regions were reduces from 32 square kilometers to 20 square kilometers, and average time of arrivals are were also improved. Hence, if related organizations plan to rearrange EMS regions, they may utilize this study.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.69-73
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• 2012

Cancer is a complex disease and the genetic susceptibility to it could be an outcome of the inherited difference in the capacity of xenobiotic metabolizing enzymes. Glutathione-S-transferases (GSTs) are phase II metabolizing enzymes whose various genotypes have been associated with increased risk of different types of cancer. Null mutations caused by the deletion of the entire gene result in the absence of the enzymatic activity and increase in the risk of developing cancer including chronic myeloid leukaemia (CML). In the present case-control study we evaluated the effect of null mutations in GSTM1 and GSTT1 genes on the risk of developing CML. The study included 75 CML patients (43 males and 32 females; age (mean ${\pm}$ S.D) $42.3{\pm}13.4$ years) and unrelated non-malignant controls (76 male and 48 females; age (mean ${\pm}$ S.D) $41.5{\pm}12.9$). The distribution of GSTM1 and GSTT1 genotypes in CML patients and controls was assessed by multiplex-PCR method. Logistic regression was used to assess the relationship between GSTM1 and GSTT1 genotypes and risk of CML. Chi-square test was used to evaluate the trend in modulating the risk to CML by one or more potential high risk genotype. Although GSTM1 null genotype frequency was higher in CML patients (41%) than in the controls (35%), it did not reached a statistical significance (OD = 1.32, 95% CI: 0.73-2.40; P value = 0.4295). The frequency of GSTT1 null genotypes was higher in the CML patients (36%) than in the controls (21%) and the difference was found to be statistically significant (OD = 2.12, 95% CI: 1.12-4.02; P value = 0.0308). This suggests that the presence of GSTT1genotype may have protective role against the CML. We found a statistically significant (OD = 3.09, 95% CI: 1.122-8.528; P value = 0.0472) interaction between the GSTM1 and GSTT1 null genotypes and thus individuals carrying null genotypes of both GSTM1 and GSTT1 genes are at elevated risk of CML.

• Food Science and Preservation
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• v.20 no.5
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• pp.668-683
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• 2013

In this study, we investigated the contents of total polyphenol (TP), total flavonoid, and absorbance at 475 nm ($OD_{475}$) which may produced in solid-fermented leaf of Smilax china L. by Aspergillus oryzae as a new functional components with reddish brown color, contents of water soluble substance (WSS), electron donating ability (EDA), Hunter $L^*$, $a^*$, $b^*$ values, sensory overall acceptability (OA) and also, the inhibitory activities (XOI and AOI) against partial purified xanthine oxidase (XO) and aldehyde oxidase (AO) from rabbit liver which were well known to relate the gout, and alcoholic liver disease, respectively in order to optimize water extraction using response surface methodology (RSM). All the $R^2$ values of the second-order polymonials ranged from 0.85 to 0.98, except for the EDA (0.69) and the XOI (0.78). However, the activities of the EDA and XOI were relatively high in the lower concentration of the fermented Smilax china L. leaf. The effects on the water extraction were highest in the concentration, among the dependent variables, and showed significant differences at the 1% level in the TP, TF and WSS contents and the $a^*$, $b^*$ and $OD_{475}$ values, but the OA showed significant differences at the 5% level. The optimal values of AOI, which was the most important functionality in the Smilax china L. that was predicted via RSM, were 59.48% at the 2.19% concentration, a $90.02^{\circ}C$ extraction temperature and a 4.03 minute extraction time ($R^2$: 0.93, p<0.007). The ranges of all the dependent variables of the optimal water extraction were 1.6~1.8% for the concentration, $83{\sim}93^{\circ}C$ for the temperature and 3.4~4.4 minutes for the extraction time; and the optimal water extraction conditions were a 1.7% concentration, an $88^{\circ}C$ extraction temperature and a 3.9-min extraction time.

• Restorative Dentistry and Endodontics
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• v.33 no.6
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• pp.537-544
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• 2008

Polymerase chain reaction (PCR) can detect bacteria more rapidly than conventional plate counting. However DNA-based assays cannot distinguish between viable and dead cells due to persistence of DNA after cells have lost their vitality. Recently, propidium monoazide (PMA) treatment has been introduced. The purpose of this study is to evaluate the applicability of the PMA treatment and real-time PCR method for cell counting in comparison with plate counting and to evaluate the antibacterial efficacy of 2% CHX on E. faecalis using PMA treatment in combination with real-time PCR. Firstly, to elucidate the relationship between the proportion of viable cells and the real-time PCR signals after PMA treatment, mixtures with different ratios of viable and dead cells were used. Secondly, relative difference of viable cells using PMA treatment in combination with real-time PCR was compared with CFU by plate counting. Lastly, antibacterial efficacy of 2% CHX on E. faecalis was measured using PMA treatment in combination with real-time PCR. The results were as follows : 1. Ct value increased with decreasing proportion of viable E. faecalis. 2. There was correlation between viable cells measured by real-time PCR after PMA treatment and CFU by plate counting until Optical density (OD) value remains under 1.0. However, viable cells measured by real-time PCR after PMA treatment have decreased at 1.5 of OD value while CFU kept increasing. 3. Relative difference of viable E. faecalis decreased more after longer application of 2% CHX.

• The Journal of the Acoustical Society of Korea
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• v.24 no.4
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• pp.186-193
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• 2005

The Terrestrial Digital Multimedia Broadcasting (T-DMB) system supplies high quality audio comparable with VCD in 7 inch display and high quality audio comparable CD at the mobile reception environment T-DMB will launch commercial service at the middle of 2005. However the bandwidth for audio data and the number of channels are restricted to 128 kbps and 2 respectively in the current T-DMB standard because of the limitation of available bandwidth for multimedia data. This Paper Proposes a novel media processor structure for providing multi-channel audio contents oyer T-DMB system allowing backward compatibility with the legacy T-DMB receiver. Furthermore. we also Propose an adaptive receiver structure to supply optimal audio contents on various speaker configuration in T-DMB receiver. To provide multi-channel audio contents allowing backward comaptilbity with the legacy T-DMB receiver, the additional data for multi-channel audio are defined as a dependent stream of main audio stream. The OD strucure for control an additional multi-channel audio elementary stream is proposed without changing the BIFS of the legacy T-DMB system.