• Journal of Nutrition and Health
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• v.24 no.4
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• pp.314-325
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• 1991

To compare the hypolipidemic effects of n6 and n3 PUFA at different fat levels, male Sprague Dawley rats were fed either low fat (LF, 10% Cal) or high fat (HF, 40% Cal) diet which was different only in fatty acid composition for 6 weeks. Dietary fats were beef tallow, corn oil, perilla oil, and fish oil concentrate as a source of saturated fatty acid, n6 linoleic acid(LA). n3 ${\alpha}-linolenic$ acid(LL) and n3 eicosapentaenoic acid(EPA)+docosahexaenoic acid(DHA), respectively. VLDL fraction was separated by ultracentrifugation and chemical composition was determined by thin layer chromatography. Plasma cholesterol level was increased by n6 LA but decreased by n3 LL and n3 EPA in LF and HF diets, and the hypocholesterolemic effect of n3 EPA was most significant in HF diet. HDL-Chol level was raised by n6 LA in LF and HF diets, but significantly reduced by n3 EPA in HF. Plasma TG level was reduced by n6 LA n3 LL and EPA in LF and HF with the reduction of lipogenic enzyme activity only by n3 PUFAs. The proportion of TG in VLDL fraction was significantly lowered by n3 EPA in LF and HF. The proportion of apo-B in VLDL fraction was not changed in LF, but was significantly decreased in HF by n3 EPA. Therefore, the hypotriglyceridemic effect of n3 PUFA could be from the reduced lipogenesis in liver and resulted in the depressed secretion of TG as VLDL in LF and HF with significant lower production of apoB in HF diet.

• Journal of the Korean Chemical Society
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• v.31 no.4
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• pp.328-333
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• 1987

1-eicosylsulfate($C_{20}H_{41}SO_4^-$) was coated onto 5 ${\mu}m$ C18 reversed phase column. Adsorption equilibrium was reached when 1.2l of $1.46{\times}10^{-4}M$ in 25% acetonitrile solution passed through the column. This coated column proved to be stable up to 10l of 0.05 M ${\alpha}$-HiBA eluent used. The column efficiencies of Eu, Nd, Ce and La measured were about 0.04 mm of HETP using 0.15M ${\alpha}$-HiBA eluent at a flow rate of 1.0ml/min. This column was used to separate some lanthanides and transition metal ions, andmshowed an excellent resolution, respectively.

• Nuclear Engineering and Technology
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• v.53 no.11
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• pp.3784-3789
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• 2021

We report a simple technique for direct neutron spectroscopy using pure LaCl₃ crystals. Pure LaCl₃ crystals exhibit considerably better pulse shape discrimination (PSD) capabilities with relatively good energy resolution as compared with Ce-doped LaCl₃ crystals. Single crystals of pure and Ce-doped LaCl₃ were grown using an inhouse-developed Bridgman furnace. PSD capabilities of these crystals were investigated using ²⁴¹Am and ¹³⁷Cs sources. Fast neutron detection was tested using a²⁵²Cf source and three separate bands corresponding to electron, proton, and alpha were observed. The proton band induced by the ³⁵Cl(n,p)³⁵S reaction can be used for direct neutron spectroscopy because proton energy is proportional to incident neutron energy. Owing to good scintillation performance and excellent PSD capabilities, pure LaCl₃ is a promising candidate for space detectors and other applications that necessitate gamma/fast neutron discrimination capability.

• Biomedical Science Letters
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• v.15 no.2
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• pp.153-160
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• 2009

Photodynamic therapy(PDT) is a treatment utilizing the generation of singlet oxygen and other reactive oxygen species(ROS), which selectively accumulate in target cells. The aim of present work is to investigate the photodynamic therapy mechanism of 9-HpbD-a-mediated PDT in HeLa cell lines. We studied the general reactive oxygen species(G-ROS) activation after 9-HpbD-a PDT using fluorescence stain with $H_2DCF-DA$. G-ROS activation observed after 9-HpbD-a PDT and higher activation condition was 1 hour after PDT at 0.5 ${\mu}g/ml$ 9-HpbD-a concentration. Sodium azide and reduced glutathione(the singlet oxygen quencher) could protect HeLa cells from cell death induced by 9-HpbD-a PDT. But D-mannitol(the hydroxyl radical scavenger) could not protect cell death. Singlet oxygen played a decisive role in 9-HpbD-a PDT induced HeLa cell death. Type II reaction was the main type of ROS formation at 9-HpbD-a PDT.

• Korean Journal of Materials Research
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• v.16 no.7
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• pp.416-421
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• 2006

The varistor properties of ZPCCL-based ceramics were investigated at different $La_2O_3$ contents in the range of $0{\sim}2.0$ mol%. As $La_2O_3$ content increased, the ceramic density greatly increased in the range of $4.71{\sim}5.77\;g/cm^3$ and the varistor voltage greatly decreased in the range of $503.5{\sim}9.4$ V. The varistor with 0.5 mol% $La_2O_3$ exhibited good nonlinearity, in which the nonlinear exponent is 81.6 and the leakage current is 0.2 ${\mu}A$. Furthermore, the varistors exhibited the high electrical stability, with $%{\Delta}V_{1mA}=-1.1%,%{\Delta}{\alpha}=-3.7%$, and $%{\Delta}I_L=+100%$ for DC accelerated aging stress condition of 0.95 $V_{1mA}/150^{\circ}C/24$ h.

• Environmental Analysis Health and Toxicology
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• v.18 no.4
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• pp.271-276
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• 2003

The purpose of the present study was to perform experiments of cytotoxicity using HeLa cell and to evaluate the possibility that QSAR is applicable to the cytotoxicity of alkylphenols. Higher toxicities were found in four alkylphenols in the following order: 4-n-Nonylphenol) 4-tert-Octylphenol) 4-n-Octylphenol > 4-n Heptylpheonl. Whereas other alkylphenols were apparently less toxic. By using Percent Hydrophilic Surface Area (PHSA) quantitative structure-activity relationships (QSARs) models were developed: Cytotoxicity (%) = 90.14089-4.72224 PHSA ($R^2$=0.2046, $\alpha$=0.0265). It is concluded that some of the obtained data are useful to determine whether QSAR methods can be of general use in predicting that until further work is undertaken to develop QSARs for a much wider range of homologous series of alkylphenol compounds.

• Korean Chemical Engineering Research
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• v.43 no.4
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• pp.503-510
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• 2005

In this research, composite alumina was prepared to add the various promoters by sol-gel method and examined its thermal stability. After sintering at $1,200^{\circ}C$, the thermal stability resulted in following order, $Si{\fallingdotseq}La$ > Ti > $Ba{\fallingdotseq}Ce$ > Y > $Zr{\fallingdotseq}Mg$, in accordance with adding the promoters. Especially in case of silica-added alumina, a phase transformation temperature to ${\alpha}$-alumina increased about $150^{\circ}C$ and after sintering at $1,200^{\circ}C$, it showed to maintain in ${\gamma}$-form and ${\delta}$-form alumina phase. Also it showed an increase of surface area from $3m^2/g$ to $71m^2/g$ compared with pure ${\alpha}$-alumina. In the case of silicaadded alumina, the characterization change of this alumina particle resulted in a delay of phase transformation because Si-O-Al bond was increased when sintered at high temperature. In case of lanthanum-added alumina, there was a sintering delay phenomenon in inter-particles as $LaAlO_3$ structure existed. The existence of lanthanum structure was confirmed by XRD and XPS analysis. It appeared on the alumina surface as $La_2O_3$ structure when it was sintered under $1,000^{\circ}C$, as the perovskite structure of $LaAlO_3$ at above $1,000^{\circ}C$ and as the magneto-plumbite structure of $LaAl_{11}O_{18}$ at above $1,300^{\circ}C$.

• The Journal of Korean Obstetrics and Gynecology
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• v.27 no.2
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• pp.1-11
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• 2014

Objectives: The purpose of this study was to investigate the effects of Longanae Arillus water extract (LA) on the production of inflammatory mediators in RAW 264.7 cell. LA is used for forgetfulness, insomnia, palpitation symptoms in korean medicine. Methods: In order to evaluate cytotoxicity of LA, cell viability was measured. To investigate anti-inflammatory effects of LA in the lipopolysacharide (LPS)-induced RAW 264.7 cell, the concentration of nitric oxide (NO) and cytokines were measured. And when p-value is below 0.05, it is judged to have the significant difference statistically. Results: 1. LA showed no cytotoxicity. 2. LA inhibited significantly the production on NO at the concentration of 50 and $200{\mu}g/ml$. 3. LA inhibited significantly the production on interleukin (IL)-$1{\beta}$ at the concentration of 25, 50, 100 and $200{\mu}g/ml$. 4. LA inhibited significantly the production on tumor necrosis factor (TNF)-${\alpha}$ at the concentration of 50, 100 and $200{\mu}g/ml$. 5. LA inhibited significantly the production on lipopolysaccharide-induced chemokine (LIX) at the concentration of 25, 100 and $200{\mu}g/ml$. 6. LA inhibited significantly the production on regulated on activation normal T cell expressed and secreted (RANTES) at the concentration of $200{\mu}g/ml$. Conclusions: These results suggest that LA has anti-inflammatory effect.

• Journal of the Korean Applied Science and Technology
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• v.4 no.2
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• pp.25-30
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• 1987

In order to investigate the effect to antioxygenic substances in Pine Needles on the photooxidation of linoleic acid (linoleic acid 100mg/10ml ethanol) added antioxidants and antioxygenic substances in Pine Needles was irradiated by the tungsten lamp attached with red fitter. The Photo oxidation of linoleic acid (LA) was conformed with Lea method and rhodan method. The following results were obtained: 1. Photooxidation of LA was greatly increased the presence of photosensitizer. However the Photo oxidation of LA without photosensitizer was smoothly increased by the irradiation. 2. The Photo oxidation of LA without irradiation occured quite lately whether photosensitizer was present or absent. 3. Photooxidation of LA under the presence of photosensitizer was inhibited by the addition of $dl-{\alpha}-tocopherol$ and the acetone fraction of methanol extract of Pine Needles but inhibited by BHT. Photooxidation of LA increased gradually as the addition of BHT increased but decreased gradually as that of acetone fraction increased.

• The Journal of Engineering Research
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• v.3 no.1
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• pp.215-222
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• 1998

The effect of La and Si addition of the thermal stabilization of $\gamma-alumina$ powers have been studied. Reagent grade $La(NO_3)_3{\cdot}6H_2O$ and $Si(OC_2H_5)_4$ were used as starting materials. These additives were introduced by wet impregnation method. Both La and Si additives suppressed the sintering of alumina and were found to be good thermal stabilizers of $\gamma-alumina$. Especially, Si drastically suppressed the phase transition of alumina at high temperatures. The major mechanisms for the thermal stabilization of alumina were seemed to be new phase formation and retardation of surface diffusion by addition of La or Si into alumina matrix.