• Macromolecular Research
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• v.17 no.2
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• pp.91-98
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• 2009

Conjugated PPV-derived block copolymers containing 2-ethylhexyloxynaphthalene unit were synthesized and characterized in this study. The resulting polymers were soluble in common organic solvents and showed good thermal stabilities, The weight-average molecular weights ($M_w$) of the copolymers ranged from 246,000 to 475,000 with PDIs of $1.3{\sim}2.1$. The optical properties of these polymers, measured both in a chloroform solution and on a film, showed a maximum absorption at $405{\sim}476\;nm$ for Copolymers $I{\sim}VIII$. In the PL spectra, Copolymers $I{\sim}VIII$ showed maximum peaks at $510{\sim}566\;nm$. The HOMOs, LUMOs and band gaps of the PPV derivatives of Copolymers $I{\sim}VIII$ were $5.30{\sim}5.77$, $3.04{\sim}3.24$, and $2.5{\sim}2.2\;eV$, respectively, The multi-layered, light-emitting diodes of ITO/PEDOT/copolymers/LiF/Al exhibited turn-on voltages of $6{\sim}2.5\;V$ Copolymer VIII exhibited the maximum brightness of $3.657\;cd/m^2$. Particularly, Copolymer VII, with an identical composition of MEH-PPV and naphthalene-PPV, showed a maximum luminance efficiency and power efficiency of 2,63 cd/A and 1.06 lm/W, respectively.

• Journal of the Korean Ceramic Society
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• v.53 no.5
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• pp.506-510
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• 2016

The eutectic melt of BaO-CuO flux is known to be a potential sintering aid for $Ba(Zr,Y)O_3$ (BZY) electrolyte for proton-conducting ceramic fuel cells (PCFCs). A density of BZY higher than 97% of theoretical density can be achieved via sintering at $1300^{\circ}C$ for 2 h using a flux composed of 28 mol% BaO and 72 mol% CuO. In the present study, chemical and structural evolution of BaO-CuO flux throughout the sintering process was investigated. An intermediate holding step at $1100^{\circ}C$ leads to formation of various impurity compounds such as $BaCuO_{1.977}$, $Ba_{0.92}Cu_{1.06}O_{2.28}$ and $Cu_{16}O_{14.15}$, which exhibit significantly larger unit cell volumes than the matrix. The presence of such secondary compounds with large lattice mismatch can potentially lead to mechanical failure. On the other hand, direct heating to the final sintering temperature produced CuO and $Cu_2O$ as secondary phases, whose unit cell volumes are close to that of the matrix. Therefore, the final composition of the flux is strongly affected by the thermal history, and a proper sintering schedule should be used to obtain the desired properties of the final product.

• Journal of Pharmaceutical Investigation
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• v.34 no.6
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• pp.513-519
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• 2004

A sensitive method for quantification of pinaverium bromide in human plasma was established using liquid chromatography-electrospray ionization tandem mass spectrometry(LC-ESI-MS/MS). Glimepiride was used as internal standard. Pinaverium bromide and internal standard in plasma sample were extracted using tert-butylmethylether(TBME). A centrifuged upper layer was then evaporated and reconstituted with mobile phase of acetonitrile-5 mM ammonium formate (80/20, pH 3.0). The reconstituted samples were injected into a $C_{18}$ reversed-phase column. Using MS/MS with multiple reaction monitoring (MRM) mode, pinaverium and glimepirde were detected without severe interference from human plasma matrix. Pinaverium produced a protonated precursor ion $([M+H]^+)$ at m/z 510.3 and a corresponding product ion at m/z 228.9. Internal standard produced a protonated precursor ion $([M+H]^+)$ at m/z 491.5 and a corresponding product ion at m/z 352.0. Detection of pinaverium bromide in human plasma was accurate and precise, with limit of quantitation at 0.5 ng/ml. The method has been successfully applied to bioavailability study of pinaverium bromide tablet in Korean healthy male volunteers. Pharmacokinetic parameters such as $AUC_t,\;C_{max},\;T_{max},\;K_{el}\;and\;t_{1/2}$ were calculated.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.5
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• pp.259-264
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• 2000

In this paper, the characteristics of piezoelectric transformer is studied for driving CCFL(Cold Cathode Fluorescent Lamp). In order to investigate the effects of geometrical dimensions, λvibration-mode type piezoelectric transformers with different sizes in the length(l), width$(\omega)$ and thickness(t) are made of ceramics with PZT-PMWS compositions. The increases in temperature and aging effect are also measured in the transformer of PT-3 sample under the condition of operation continuously for 10 hrs. As the results of dimensional effects, the output power and voltage step-up ratio are largely affected by the ratio of length to thickness(l/t) rather than that of length to $width(l/\omega)$. The output power and step-up ratio are increased with increasing l/t. On case of PT-3, the output voltages are 510[Vrms] at 36[Vrms] in input voltage, $100[k\Omega]$ in load resistance. Temperature increases and variation of output voltages are $10[^{\circ}C]$ and less than 5[%], respectively.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.6
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• pp.505-510
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• 2013

Electroacupuncture (EA) is a modified form of acupuncture that utilizes electrical stimulation. We previously showed that EA stimulated rats were divided into responders that were sensitive to EA and non-responders that were insensitive to EA based on the tail flick latency (TFL) test. The dopamine beta-hydroxylase (DBH) gene was more abundantly expressed in the hypothalamus of responder rats than non-responder rats. To determine whether overexpression of DBH gene expression in the hypothalamus modulate EA analgesia, we constructed a DBH encoding adenovirus and which was then injected into the hypothalamus of SD rats. Microinjection of DBH or control GFP virus into the hypothalamus had no changes on the basal pain threshold measured by a TFL test without EA treatment. However, the analgesic effect of EA was significantly enhanced from seven days after microinjection of the DBH virus, but not after injection of the control GFP virus. DBH expression was significantly higher in the hypothalamus of DBH virus injected rat than control GFP virus or PBS injected rats. Moreover, expression of the DBH gene did not affect the body core temperature, body weight, motor function or learning and memory ability. Although the functional role of DBH in the hypothalamus in the analgesic effect of EA remains unclear, our findings suggest that expression of the DBH gene in the hypothalamus promotes EA analgesia without obvious side-effects.

• Korean Journal of Medicinal Crop Science
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• v.17 no.5
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• pp.321-327
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• 2009

Sunlight, and in particular its UV component, is the major environmental trigger that underlies the major signs of human skin and skin cancer in general. Therefore, this study was carried out to investigate the UV protection effects of R. coreanus. R. coreanus was extracted by ultra high pressure extraction process at 500 MPa and $30^{\circ}C$ for 5 and 15 minutes. The cytotoxicity of the extracts extracted by ultra high pressure process on human dermal fibroblast cell CCD-986sk, human kidney normal cell HEK293, and human lung normal cell HEL299 was measured as 17.5%, 16.5% and 14.0%, respectively in adding $1.0\;mg/m{\ell}$ of the samples, which was much lower than that from conventional water extraction method at $100^{\circ}C$ as 23.2%, 22.5%, 21.2%. The secretion of $NO^-$ from macrophage showed $15.9\;{\mu}M$ on the R. coreanus extract from this process, which was higher than others. Prostaglandin $E_2$ ($PGE_2$) production from UV-induced human skin cells was also greatly decreased down to $510\;pg/m{\ell}$, compared to the control. From the results, we considered that the extracts from R. coreanus could be potent natural materials for skin anti-inflammation agent, and could be used as a potential anti-aging for the photo-damaged skin.

• BMB Reports
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• v.40 no.4
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• pp.501-510
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• 2007

Sex-related genes expressed in vitellogenic ovaries of the giant tiger shrimp, Penaeus monodon, were identified by an EST approach. A total of 1051 clones were unidirectionally sequenced from the 5 terminus. Nucleotide sequences of 743 EST (70.7%) significantly matched known genes previously deposited in the GenBank (E-value <$10^{-4}$) whereas 308 ESTs (29.3%) were regarded as newly unidentified transcripts (E-value >$10^{-4}$). A total of 559 transcripts (87 contigs and 472 singletons) were obtained. Thrombospondin (TSP) and peritrophin (79 and 87 clones accounting for 7.5 and 8.3% of clones sequenced, respectively) predominated among characterized transcripts. everal full length transcripts (e.g. cyclophilin, profillin and thioredoxin peroxidase) were also isolated. A gene homologue encoding chromobox protein (PMCBX, ORF of 567 nucleotides encoding a protein of 188 amino acids) which is recognized as a new member of the HP1 family was identified. Expression patterns of 14 of 25 sex-related gene homologues in ovaries and testes of P. monodon broodstock were examined by RT-PCR. Female sterile and ovarian lipoprotein receptor homologues were only expressed in ovaries whereas the remaining transcripts except disulfide isomerase related P5 precursor and adenine nucleotide translocator 2 were higher expressed in ovaries than testes of P. monodon broodstock. A homologue of ubiquitin specific proteinase 9, X chromosome (Usp9X) revealed a preferential expression level in ovaries than testes of broodstock-sized P. monodon (N = 13 and 11, P<0.05) but was only expressed in ovaries of 4-month-old shrimp (N = 5 for each sex).

• Journal of the Korean Society of Safety
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• v.20 no.2 s.70
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• pp.56-60
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• 2005

We studied fire properties of MOF(Metering Out Fit) insulation cover and field condition of 22.9kV power receiving system. $49.5\%$ of formal equipments were installed indoors, whereas $40.8\%$ of informal equipments were installed as H-type. Insulation treatment was not done at a $22.4\%$ ratio of main line($27.7\%$ of transformer, $70.2\%$ of COS, $10.4\%$ of MOF). Fire pattern analysis showed that the fire started at the secondary part of OC wire. In the result of DTA(Differential Thermal Analysis), normal cover showed exothermic reactions at $310^{\circ}C,\;399^{\circ}C\;and\;510^{\circ}C$ (endothermic reactions at $382^{\circ}C$). Whereas damaged cover showed exothermic reactions at $412^{\circ}C$(endothermic reactions at $389^{\circ}C$). In the result of TGA(Thermo Gravimetric Analysis), the thermal weight change of normal cover was similar compared to damaged cover. In the result of FT-IR analysis, normal cover showed absorption peaks at $3,024cm^{-l},\;2,921cm^{-l},\;1,600cm^{-1},\;1,492cm^{-1},\;1,451cm^{-1},\;1,154cm^{-l},\;1,027cm^{-1},\;906cm^{-1}$. Whereas, in case of tracked cover, the absorption peaks that were shown in normal cover disappeared and different absorption peak was shown at $966cm^{-1}$.

• Clinical and Experimental Pediatrics
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• v.46 no.5
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• pp.510-513
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• 2003

Duplication of chromosome 7q has been reported as either partial or complete. Partial 7q duplication was first described by Carpentier in 1972. Pure partial duplication of the long arm of chromosome 7 is extremely rare and only 16 cases with a pure partial duplication of different 7q segment have been described in the literature. Pure partial duplication of the long arm of chromosome 7 is characterized by growth and developmental retardation, muscular hypotonia, distinct craniofacial dysmorphic features, a short neck and skeletal abnormalities. A 3 month-old male was referred to our department of Pediatrics because of dyspnea, hypotonia and delayed development. He shows growth and developmental delay, hypertelorism, a depressed nasal bridge, low set ears, a short neck and muscular hypotonia. Karyotype revealed 46, XY, dup(7)(q36q33) by GTC-banding. We report a case of a partial inverted duplication of chromosome 7q.

• Journal of Preventive Medicine and Public Health
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• v.28 no.2 s.50
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• pp.497-510
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• 1995

This study was carried out to assess work ability of manufacturing workers and managerial workers. Subjects were 446 manufacturing workers and 278 managerial workers employed in Gumi industrial complex and the observation period was for 1 month(February to March), 1995. In this study, as a questionnaire for the assessment of work ability, we used the Work Ability Index(WAI) which was developed by Institute of Occupational Health in Finland. Major findings obtained from this study were as follows ; WAI was poor in lower economic condition, shift work, irregular diet group(p<0.05). There were no evident trends of WAS in sex, educational level, obesity index, exercise, smoking, and alcohol drinking. In the groups of sensitive to perception of stress, other industrial classification except textile and electronics, the more than 9 hours work, the evident trends of poor WAS were observed(p<0.01). In the groups of $30\sim39$ years old, $40\sim49$ years old, unmarried, high school, shift work, standard body weight, and regular .diet, WAI between manufacturing workers and managerial workers was significantly different(p<0.01) and WAI of managerial worker was worse than that of manufacturing worker.