• Journal of Environmental Science International
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• v.13 no.1
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• pp.41-45
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• 2004

In this study, The decomposition of gas-phase Benzene and Toluene, Xylene in air streams by direct UV Photolysis, UV/TiO$_2$ and UV/TiO$_2$/A.C process was studied. The experiments were carried out under various UV light intensities and initial concentrations of B.T.X to investigate and compare the removal efficiency of the pollutant. B.T.X was determined by GC-FID of gas samples taken from the a glass sampling bulb which was located at reactor inlet and outlet by gas-tight syringe. From this study, the results indicate that UV/TiO$_2$/A.C system (photooxidation-photocatalytic oxidation-adsorption process) is ideal for treatment of B.T.X from the small workplace. Although the results needs more verifications, the methodology seems to be reasonable and can be applied for various workplace (laundry, gas station et al.).

• Bulletin of the Korean Chemical Society
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• v.17 no.10
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• pp.909-918
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• 1996

Syntheses of carbapenam skeletons were achieved from 1,3-propanediol through 1,3-dipolar cycloaddition. 3-(Tetrahydropyran-2-yloxy)-(10) and 3-(t-butyldimethylsilyloxy) propanal (13) were obtained from 1,3-propanediol. 3-Hydroxypropanals (10, 13, 14) were reacted with N-hydroxyglycine esters to give C-(2-hydroxyethyl)-N-alkoxycarbonylmethylnitrones (15a-15d). 1,3-Dipolar cycloaddition of the nitrones with methyl acrylate or ethyl crotonate gave 3-(2-hydroxyethyl)isoxazolidines (16a-16b, 17a-17b, 18, 19a-19b). 3-(2-Hydroxyethyl)isoxazolidines (17a, 17c, 19a, 19b) were converted to 3-(2-iodoethyl)isoxazolidines (21a-21d) or 3-phenylthiocarbonylmethylisoxazolidines (25a-25d) which were cyclized to give 2-oxa-1-azabicyclo[3.3.0]octanedicarboxylates (22a-22d, 26a-26d). 2-Oxa-1-azabicyclo[3.3.0]octane-4,8-dicarboxylates (22c-22d, 26c-26d) were transformed to 6-(l-hydroxyethyl)carbapenam-3-carboxylates (30a-30b, 31a-31b).

• YAKHAK HOEJI
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• v.48 no.5
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• pp.272-277
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• 2004

The 2-amino-l-phenylpropanols 4∼7 were reacted with isothiocyanates to afford the 20 thioureido MAPP derivatives 8a∼11e, which were tested their cytotoxic activity by MTT assay. The cytotoxicity of alkylthioureido compounds were increased and decreased by alkyl chain length from $C_{8}$ to $C_{14}$ and of phenylthioureido compounds showed poor activity. The compounds (8b, 8c, 9b, 9c, l0b, 10c, 11b, 11c) with $C_{10}$ and $C_{12}$ alkyl chains gave stronger activity than reference compound B13. The $IC_{50}$/ of compound 8c was 1.05$\mu$M and 3 times stronger activity than B13. The stereochemistry of synthesized compounds affected very little to cytotoxic activity.

• Ocean Systems Engineering
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• v.13 no.2
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• pp.97-121
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• 2023

Through-the-thickness stress distribution in a tubular member has a profound effect on the fatigue behavior of tubular joints commonly found in steel offshore structures. This stress distribution can be characterized by the degree of bending (DoB). Although multi-planar joints are an intrinsic feature of offshore tubular structures and the multi-planarity usually has a considerable effect on the DoB values at the brace-to-chord intersection, few investigations have been reported on the DoB in multi-planar joints due to the complexity of the problem and high cost involved. In the present research, data extracted from the stress analysis of 243 finite element (FE) models, verified based on available parametric equations, was used to study the effects of geometrical parameters on the DoB values in two-planar tubular DYT-joints. Parametric FE study was followed by a set of nonlinear regression analyses to develop six new DoB parametric equations for the fatigue analysis and design of axially loaded two-planar DYT-joints.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.2263-2267
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• 2012

Objective: MicroRNAs (miRNAs) play important roles in carcinogenesis. The aim of the present study was to explore the effects of miR-181b on gastric cancer. Methods: The expression level of miR-181b was quantified by qRT-PCR. MTT, flow cytometry and matrigel invasion assays were used to test proliferation, apoptosis and invasion of miR-181b stable transfected gastric cancer cells. Results: miR-181b was aberrantly overexpressed in gastric cancer cells and primary gastric cancer tissues. Further experiments demonstrated inducible expression of miR-181b by Helicobacter pylori treatment. Cell proliferation, migration and invasion in the gastric cancer cells were significantly increased after miR-181b transfection and apoptotic cells were also increased. Furthermore, overexpression of miR-181b downregulated the protein level of tissue inhibitor of metalloproteinase 3 (TIMP3). Conclusion: The upregulation of miR-181b may play an important role in the progress of gastric cancer and miR-181b maybe a potential molecular target for anticancer therapeutics of gastric cancer.

• Journal of the Korean Chemical Society
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• v.44 no.5
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• pp.435-440
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• 2000

The reaction of 2-methoxycarlmethylen-l,2-dihydro-4H-pyrido[2,3-b]pyrazin-3-one(5) with hydrazine hydrate and ethylenediamine gave 2-hydrazinocarbonylmethylene-1,2-dihydro-4H-pyrido[2,3-b]pyrazin-3-one(6) and 2-aminoethylcarbamethylene-1,2-dihydro-4H-pyrido[2,3-b]pyrazin-3-one(7), res-pectively. The reaction of compound 6 or 7 with substituted benzaldehydes or heteroaryl aldehydes afforded pyrido[2,3-b]pyrazines(8-13). Some pyrin the enamine, methylene imine and enaminol forms in solution. The tau-tomer ratios were determined by the H NMR.

• Journal of Advanced Navigation Technology
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• v.6 no.2
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• pp.113-118
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• 2002

In this paper, an internal GPS antenna for mobile phones is designed and fabricated. For the miniaturization of the antenna, high permittivity dielectric substrate((${\varepsilon}_r$=90) and small ground plane ($13mm{\times}13mm$) are used. To increase the receive gain, the antenna is composed with LNA(Low Noise Amplifier). Results of the manufactured antenna($13mm{\times}13mm{\times}8mm$) show that the maximum antenna gain is about 12 dBi, the axial ratio is less than 3 dB, and the current consumption of LNA is less than 4 mA.

• IMMUNE NETWORK
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• v.21 no.2
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• pp.13.1-13.19
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• 2021

Macrophages are important for the first line of defense against microbial pathogens. Integrin CD11b, which is encoded by Itgam, is expressed on the surface of macrophages and has been implicated in adhesion, migration, and cell-mediated cytotoxicity. However, the functional impact of CD11b on the inflammatory responses of macrophages upon microbial infection remains unclear. Here, we show that CD11b deficiency resulted in increased susceptibility to sepsis induced by methicillin-resistant Staphylococcus aureus (MRSA) infection by enhancing the pro-inflammatory activities of macrophages. Upon infection with MRSA, the mortality of Itgam knockout mice was significantly higher than that of control mice, which is associated with increased production of TNF-α and IL-6. In response to MRSA, both bone marrow-derived macrophages and peritoneal macrophages lacking CD11b produced elevated amounts of pro-inflammatory cytokines and nitric oxide. Moreover, CD11b deficiency upregulated IL-4-induced expression of anti-inflammatory mediators such as IL-10 and arginase-1, and an immunomodulatory function of macrophages to restrain T cell activation. Biochemical and confocal microscopy data revealed that CD11b deficiency augmented the activation of NF-κB signaling and phosphorylation of Akt, which promotes the functional activation of macrophages with pro-inflammatory and immunoregulatory phenotypes, respectively. Overall, our experimental evidence suggests that CD11b is a critical modulator of macrophages in response to microbial infection.

• Textile Coloration and Finishing
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• v.19 no.3
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• pp.18-25
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• 2007

The fixing behaviors of anthraquinone disperse dyes containing dimethylamino substituent, such as C. I. Disperse Violet 26(D.V.26) and C. I. Disperse Blue 14(D.V.14), or containing diamino substituent, such as C. I. Disperse Blue 73(D.B.73), and monochlorotriazinyl azo reactive dyes, such as C. I. Reactive Orange 13(R.O.13), C. I. Reactive Red 3(R.R.3). C. I. Reactive Yellow 2(R.Y.2) on polyester/cotton blend(P/C) fabrics were examined for the one-step printing of P/C fabrics. The high temperature steaming of $175^{\circ}C$ is the most satisfactory fixing method for P/C one-step printing with above disperse and reactive dyes among the four different fixing methods: $175^{\circ}C$ steaming, $102^{\circ}C$ steaming${\rightarrow}175^{\circ}C$ steaming, $190^{\circ}C$ thermosol, $102^{\circ}C$ steaming${\rightarrow}190^{\circ}C$ thermosol. $190^{\circ}C$ thermosol is unfit to fix R.R.3 and R.Y.2 whose heat stability is poor. It was found that D.V.26 and D.B.14 containing dimethylamino substituent are unstable for heat and alkali, but D.B.73 is stable for them to print P/C blend fabrics with R.O.13 which is also stable for heat. Therefore we found that D.B.73, R.O.13 and a pair of D.B.73 and R.O.13 were very suitable for one-step printing of P/C blend fabrics.

• Journal of Photoscience
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• v.9 no.2
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• pp.110-113
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• 2002

We demonstrate here a dynamic structure of bacteriorhodopsin (bR) as revealed by $^{13}$ C NMR studies on [3_$^{13}$ C]_,[1-$^{13}$ C]Ala- and/or Val-labeled wild type and a variety of site-directed mutants at ambient temperature. For this purpose, well-resolved (up to twelve) I$^{13}$ C NMR peaks were assigned with reference to the displacement of peaks due to the conformation-dependent I$^{13}$ C chemical shifts and reduced peak-intensities due to site-directed mutations. Revealed bR structure was not rigid as anticipated from 2D crystals of hexagonal array but a dynamically heterogeneous, undergoing a variety of local fluctuations depending upon specific site with frequency range of 10$^2$ -10$^{8}$ Hz. In particular, dynamics- dependent suppression of peaks turned out to be very sensitive to the motion of 10$^{-4}$ s and 10$^{-5}$ s interfered with frequency of magic angle spinning and proton decoupling, respectively. It is also noteworthy that such dynamic feature is strongly dependent upon the manner of 2D crystalline packing: $^{13}$ C NMR peaks of monomeric bR yielded either highly broadened or completely suppressed signals, depending upon the type of $^{13}$ C-labeled amino-acid residues.