• Journal of the Korean Chemical Society
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• v.42 no.6
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• pp.679-695
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• 1998

A series of ${\alpha}{\omega}-bis[4-(4'-(S)-(+)-2-methylbutylbiphenyl-4-carboxy)phenoxy]alkanes$, were synthesized, and their thermal and liquid crystalline properties were studied. The chain length of the central polymethylene spacers, x, of the chiral twin compounds was varied from 3 to 12. These compounds were characterized by elemental analysis, IR and NMR spectroscopy, differential thermal analysis (DSC), and crosspolarized microscopy. All compounds were found to be enantiotropic liquid crystalline, and the values of melting $(T_m)$ and isotropization temperature $(T_i)$ as well as ${\delta}H_I$ and ${\delta}S_I$ decreased in a zig-zag fashion, revealing the so called odd-even effect as x increased. Their mesomorphic properties fell into four categories depending upon x; (a) compounds with x=3, 4 and 5 formed only a cholesteric phase on heating, while on cooling they went through two transitions of isotropic (I)-to-cholesteric (Ch) and Ch-to-smectic $A\;(S_A)$ phases before crystallization. (b) compounds with x=6, 8 and 10 exhibited only a cholesteric phase both on heating and on cooling. (c) compounds with x=7 and 9 went through three transitions of crystal $(C)-to-S_A,\;S_A-to-Ch,$ and Ch-to-I phases on heating while on cooling they went through four transitions of I-to-Ch, $Ch-to-S_A,\;S_A-to-Smectic\;C\;(S_C),\;and\;S_c-to-C$ phases in that order, and (d) compounds with x=11 and 12 went reversibly through four transitions of $C-to-S_C,\;S_C-to-S_A,\;S_A-to-Ch,$ and Ch-to-I phases.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.4
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• pp.62-66
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• 1979

These studies were designed to define the effects of Benzyladenine and 2, 4-D on the induction and growth of callus tissue from embryos and plant segments of Korean ginseng. 0.5PPM was the minimum concentration of 2, 4-D for the induction of callus tissue from embryos and plant segments of ginseng. Best callus induction occurred at a 2, 4-D concentration of 5 mg/liter but growth of this callus was best at a 2, 4-D concentration of about 1.0 to 2.0 mg/liter and benzyladenine was ineffective as callus inducer. When the embryos were grown on the media containing 0.5 mg/liter of 2, 4-D, 5 to 6 axillary buds were formed at the basal part of epicotyle.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11b
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• pp.43-48
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• 2004

Undoped and $Co^{2+}$-doped $CaGa_2S_4$, $CaGa_2Se_4$, $CaIn_2S_4$. and $CaIn_2Se_4$ single crystals were grown by using the chemical transport reaction method The temperature dependence of the optical energy gap was well fitted by the Varshni equation. In the Co2+ - doped $CaGa_2S_4$, $CaGa_2Se_4$, $CaIn_2S_4$, and $CaIn_2Se_4$ single crystals, two groups of impurity optical absorption peaks due to Co2+ sited in a Td symmetry were observed in the wavelength regions of 600 900 nm and 1350 1950 nm at 11 K.耀

• Composites Research
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• v.12 no.4
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• pp.8-16
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• 1999

In this study, when the applied directions of tensile loading is changed fatigue damage of quasi-isotropic composite laminates was discussed. Low cycle fatigue tests of $[0/-60/+60]_s$ laminates and $[+30/-30/90]_s$ laminates were carried out. Material systems used were AS4/Epoxy and AS4/PEEK. The fatigue damage of $[+30/-30/90]_s$ laminates differed from that of $[0/-60/+60]_s$ laminates. The position of delamination generated at AS4/Epoxy and AS4/PEEK $[+30/-30/90]_s$ laminates appeared differently according to the kind of matrix. Critical values of strain energy release rate were obtained by using the strain measured at the initiation of delamination. The experimental results agreed well with the results obtained by the proposed method for determining strain energy release rate.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.239-242
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• 2004

A stoichiometric mixture of evaporating materials for $CdIn_2S_4$ single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films, $CdIn_2S_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by hot wall epitaxy(HWE) system. The source and substrate temperatures were $630^{\circ}C$ and $420^{\circ}C$ respectively. The crystalline structure of single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction(DCXD). The carrier density and mobility of $CdIn_2S_4$ single crystal thin films measured from Hall effect by van der Pauw method are $9.01{\times}10^{16}\;cm^{-3}$ and $219\;cm^2/V{\cdot}s$ at 293 K, respectively. From the optical absorption measurement, the temperature dependence of energy band gap on $CdIn_2S_4$ single crystal thin films was found to be $E_g(T)\;=\;2.7116\;eV\;-\;(7.74{\times}10^{-4}\;eV)T^2/(T+434)$. After the as-grown $CdIn_2S_4$ single crystal thin films was annealed in Cd-, S-, and In-atmospheres, the origin of point defects of $CdIn_2S_4$ single crystal thin films has been investigated by the photoluminescence(PL) at 10 K.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.1
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• pp.82-89
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• 1986

This study was designed to observe the effects of dietary P/S ratio on lipid component in plasma and tissues. Changes in plasma total cholesterol and triglyceride concentration and also cholesterol and triglyceride concentrations in liver, small intestine and aorta were determined in adult rats fed experimental diets providing different dietary P/S ratios as 0.05, 0.5, 1.0, 2.0, 3.0, and 4.0, respectively. The results obtained were summarized as follows; 1. Feed efficiency ratio was not significantly different among six groups at 2nd week. But at 4th week, the higher the dietary P/S ratio the higher the feed efficiency ratio. 2. Plasma cholesterol level was getting higher as increased dietary P/S ratio at 2nd week, But that was significantly decreased as P/S ratio increased at 4th week. 3. Plasma triglyceride level was significantly decreased as increased dietary P/S ratio at 4th week. 4. Cholesterol concentrations in liver and small intestines were getting higher as increased dietary P/S ratio at 4th week, But aortas cholesterol concentration was not influenced by P/S ratio. 5. Triglyceride concentrations in liver and small intestines were significantly increased as increased dietary P/S ratio. On the contrary, triglyceride concentration in aortas was not influenced by P/S ratio.

• Applied Biological Chemistry
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• v.37 no.5
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• pp.402-408
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• 1994

For the examination of the role of monocerin(1) on the biological activity, (8S, 9S, 11R)-(-)-monocerin(20) and (9S, 11R)-(+)-fusarentin 4, 5-dimethyl ether(19) were synthesized by a condensation of the benzylic anion of ethyl 2, 3, 4-trimethoxy-6-methylbenzoate(16) with modifyed (R)-ethyl 3-hydroxyhexanoate (9). In a key step, bioreduction with active dried baker's yeast in organic solvent system was employed to get a chiral aldehyde 12. Their phytotoxic activities were tested on rice seedlings and lettuce seeds.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.6
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• pp.773-783
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• 1998

The heating system for apartment complex may be classified as old systems including central system with steam boiler(S1), gas engine driven heat pump system(S2), system using waste heat(S3) and new systems including mechanical vapor re-compression system with flashing heat exchangers(S4), system using methanol(S5), system using metal hydride (S6). The purpose of the present study is to suggest optimal heating system by technically, economically and environmentally evaluating old and new heating systems of apartment complex from 500 to 3,000 households. Economic evaluation based on the technical evaluation results which estimated heat transfer area of heat exchangers and capacity of equipments was estimated initial investment cost, annual operating cost and relative payback period by considering annual increasing rates of energy cost and interest. Environmental evaluation provided annual generation rate of carbon dioxide. Initial investment cost was cheap in the order of S6, S5, S3, S2, S4, S1, annual operating cost was cheap in the order of S1, S2, S4, S5 and relative payback period was short in the order of S6, S5, S2, S3 and S4. Relative payback period was within 8 years for all scenarios of 3,000 households, and was increased as annual increasing rates of energy cost and interest were increased. As transportation pipe length was increased twice, payback period was increased by 1.4~2.6 time. The effect of temperatures of waste gas and waste water on the relative payback period was small within 0.8 years. The annual generation rate of carbon dioxide was big in the order of S4, S2 and S1. S4 was the most economic system among whole scenarios when S1 was replaced with other scenarios.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.7
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• pp.2883-2887
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• 2015

Background: The calcium-binding S100A4 protein is involved in epithelial to mesenchymal transition, oncogenic transformation, angiogenesis, cytoskeletal integrity, mobility and metastasis of cancer cells. This study aimed to clarify the roles of S100A4 in genesis and progression of glioma. Materials and Methods: S100A4 expression was examined by real-time RT-CPR and Western blot in glioma and paired normal brain tissue (n=69), and compared with clinicopathological parameters of tumors. In addition, glioma U251 cells transfected with an S100A4-expressing plasmid were examined for proliferation by MTT, apoptosis by Annexin V-FITC, and migration and invasion with Transwell chambers. Results: Increased S100A4 mRNA expression was found in gliomas, compared with paired non-tumor tissue (p<0.001). Gradual elevation of overexpression of S100A4 was observed with increasing glioma grade (p<0.001). Astrocytoma showed lower S100A4 mRNA expression than oligodendrogliomas, with glioblastomas having highest values (p<0.001). Similar results were obtained for S100A4 protein, a positive link being found between mRNA and protein expression in gliomas (p<0.001). There was higher growth, lower apoptosis, stronger migration and invasion of S100A4 transfectants than control and mock transfected cells (p<0.001). Conclusions: These findings indicate that up-regulated S100A4 expression is positively linked to pathogenesis, progression and histogenesis of glioma by modulating proliferation, apoptosis, migration and invasion.

• Journal of Society of Preventive Korean Medicine
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• v.10 no.1
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• pp.141-153
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• 2006

In order to study the changes in hematology and serum chemistry of rats injected with glycerol, Sprague-Dawley albino rats weighing 240 to 260 gm were injected intramuscularly with a 50% solution of glycerol(8ml/kg). We measured the values of hematology and serum chemistry, and compared the measured values of S1 group(passed for 1day after injection of glycerol), S2 group(passed for 2days after injection of glycerol), S3 group(passed for 3days after injection of glycerol), S4 group(passed for 3days after injection of glycerol) and S5 group(passed for 4days after injection of glycerol) with those of Normal group(non-treated group). The results are summarized as follows : 1. In body temperature, S1, S2, S4 groups showed significantly higher compared with Normal group, especially S2 group was higher than S1 group(p<0.05). But S5 group was lower than Normal group(p<0.05). 2. In RBC, S1 group was lower than Normal group(p<0.05). And in Hct, S1, S2, S3 groups were lower than Normal group(p<0.05), in Hb, S1 and S3 groups were lower than Normal group(p<0.05). 3. In WBC, S1, S2 groups were higher than Normal group(p<0.05). and in WBC differential count, S2, S3, S5 groups were higher than N, S1, S4 groups in monocyte(p<0.05). 4. In GOT, S1 group was higher than Normal group(p<0.05), and S2, S3, S4, S5 groups were lower than S1 group(p<0.05). In GPT, S1 group was higher than Normal group(p<0.05), and S2, S3 groups were lower than S1 group(p<0.05), S4, S5 groups were lower than N, S1, S2, S3 groups(p<0.05). 5. In total cholesterol and creatinine, S4 group was higher than Normal group(p<0.05). According to the above experimental results, we could find the anemia, inflamation, damage of renal function for 4 days by intramuscularly injection with a 50% solution of glycerol(8ml/kg) in rat.