• Korean Journal of Optics and Photonics
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• v.7 no.2
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• pp.162-166
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• 1996

We report a fiber optic interferometric electric field sensor that utilizes electrostrictive ceramics-1%, 2%, 3%, La-doped 0.9MN/0.1PT, respectively-as the transducing elements. It is also experimentally observed that 3% La-doped PMN/PT among the three elements has the largest electrostrictive coefficient $M=3.87{\times}10^ {-16}(m/V)^2$ at 3.38 kHz and displays small hysteresis. The optical fiber sensor with the 3% La-doped PMN/PT exhibits minimum detectable field of 2.08(V/m)/ $\sqrt{Hz}$ and has a good linearity over the dynamic range 40 dB.

• Journal of the Korean Chemical Society
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• v.21 no.2
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• pp.89-93
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• 1977

Faujasite type zeolite synthesized from kaolin minerals was cation-exchanged and the catalytic activities of $1-Butene{\rightarrow}2-butene$ took place readily even on zeolites having no strong acid sites. The order of activity for isobutene formation was La > H > Zn > Na-faujasite, La-faujasite showing much higher activity. The same trend was observed for propylene formation except that both La-and H-faujasite showed comparable activity. The results seem to indicate that the activities for 1-buten cracking and isomerization on zeolite are directly related to the strength and concentration of the acid sites on zeolites.

• Applied Biological Chemistry
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• v.46 no.2
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• pp.84-89
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• 2003

In order to find a chemical agent which is able to modulate the activity of $H^+-ATPase$, microsomal preparation was obtained from the root tissue of tomato plant and the effect of $La^{3+}$ was measured. The activities of plasma and vacuolar membrane $H^+-ATPase$ were analyzed by the inhibited activities using their specific inhibitors, vanadate and $NO_3-$, respectively. $La^{3+}$ inhibited microsomal ATPases in a dose-dependent manner and the inhibitory effect of $La^{3+}$ was suppressed by both vanadate and $NO_3-$, implying that $La^{3+}$ inhibits both plasma and vacuolar membrane $H^+-ATPase$. The Ki. values of $La^{3+}$which inhibit 50% of the activities of plasma and vacuolar membrane $H^+-ATPase$ were 57 and $78\;{\mu}M$, respectively. The $H^+-ATPase$ of the leaky microsomes made by the treatment of Triton X-100 were also inhibited by $La^{3+}$, suggesting that $La^{3+}$ directly inhibits both enzymes. Meanwhile, the inhibitory effect of $La^{3+}$ was decreased by increasing the concentration of ATP, The effect of ATP was also concentration-dependent and 7 mM ATP completely removed the inhibitory effect of $La^{3+}$. These results imply that $La^{3+}$ inhibits both plasma and vacuolar membrane $H^+-ATPases$ by decreasing the binding affinity of ATP and $La^{3+}$ can be used to control the activity or root $H^+-ATPases$.

• Proceedings of the Korean Magnestics Society Conference
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• 2010.06a
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• pp.122-123
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• 2010

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.3
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• pp.157-161
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• 2017

$(1-x)Bi_{0.5}(Na_{0.78}K_{0.22})_{0.5}TiO_3-xLaFeO_3$ ceramics were fabricated using a solid state reaction method. The microstructural, ferroelectric and piezoelectric properties were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), and polarization hysteresis loops (P-E). XRD results indicated that BNKT ceramic crystal structure modified by $LaFeO_3$ was transformed from a ferroelectric tetragonal to a non-polar pesudo-cubic phase with increased $LaFeO_3$ content. The improved piezoelectric properties resulted from the addition of $LaFeO_3$ up to 3 mol%. The $LaFeO_3$ 3mol% sample showed markedly improved piezoelectric and strain behaviors in comparison with pure BNKT ceramic.

• Journal of Chest Surgery
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• v.45 no.1
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• pp.1-10
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• 2012

Background: ${\alpha}$-Lipoic acid (${\alpha}$-LA) has been studied as an anticancer agent as well as a therapeutic agent for diabetes and obesity. We performed this study to evaluate the anticancer effects and mechanisms of ${\alpha}$-LA in a lung cancer cell line, A549. Materials and Methods: ${\alpha}$-LA-induced apoptosis of A549 cells was detected by fluorescence-activated cell sorting analysis and a DNA fragmentation assay. Expression of apoptosis-related genes was analyzed by western blot and reverse transcription.polymerase chain reaction analyses. Results: ${\alpha}$-LA induced apoptosis and DNA fragmentation in A549 cells in a dose- and time-dependent manner. ${\alpha}$-LA increased caspase activity and the degradation of poly (ADP-ribose) polymerase. It induced expression of endoplasmic reticulum (ER) stress-related genes, such as glucose-regulated protein 78, C/EBP-homologous protein, and the short form of X-box binding protein-1, and decreased expression of the anti-apoptotic protein, X-linked inhibitor of apoptosis protein. Reactive oxygen species (ROS) production was induced by ${\alpha}$-LA, and the antioxidant N-acetyl-L-cysteine decreased the ${\alpha}$-LA-induced increase in expression of apoptosis and ER stress-related proteins. Conclusion: ${\alpha}$-LA induced ER stress-mediated apoptosis in A549 cells via ROS. ${\alpha}$-LA may therefore be clinically useful for treating lung cancer.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.7
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• pp.996-1002
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• 2014

An experiment was conducted to evaluate the effects of dietary alpha-lipoic acid (LA) and acetyl-L-carnitine (ALC) on growth performance, carcass characteristics and meat quality in Arbor Acres broilers. A total of 486 1-d-old male Arbor Acres broilers were randomly allocated to 9 dietary treatments, 9 treatments were group A (0 mg/kg LA and 0 mg/kg ALC), group B (50 mg/kg LA and 0 mg/kg ALC), group C (100 mg/kg LA and 0 mg/kg ALC), group D (0 mg/kg LA and 50 mg/kg ALC), group E (50 mg/kg LA and 50 mg/kg ALC), group F (100 mg/kg LA and 50 mg/kg ALC), group G (0 mg/kg LA and 100 mg/kg ALC), group H (50 mg/kg LA and 100 mg/kg ALC), group I (100 mg/kg LA and 100 mg/kg ALC). Birds were slaughtered at 42 days old. Average daily gain (ADG), average feed intake (AFI), feed conversion rate (FCR), eviscerated rate, breast muscle percentage, thigh muscle percentage, abdominal fat percentage, liver weight, muscle color ($L^*$ value, $a^*$ value, $b^*$ value), pH values at 45 min and 24 h postmortem were measured. Results showed that there existed an interaction between LA and ALC in growth performance of broilers, carcass traits and meat quality. The overall result is that high level of LA and ALC led to lower AFI, ADG (p<0.01), lower abdominal fat percentage, liver weight (p<0.01), lower $L^*$ value, $a^*$ value, and $b^*$ value of breast muscle, $L^*$ value of thigh muscle (p<0.05), and higher FCR (p<0.01), eviscerated rate (p<0.01), breast muscle percentage, thigh muscle percentage (p<0.05), $a^*$ value, pH 45 min and pH 24 h of thigh muscle (p<0.01). These results suggested that dietary LA and ALC contributed to the improvement of meat quality in broilers.

• Development and Reproduction
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• v.5 no.2
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• pp.181-187
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• 2001

Seasonal changes and circadian rhythm of plasma prolactin(PRL) concentration in mammals are mediated by melatonin. Pinealectomy or denervation of the pineal gland produces an increase in plasma PRL level. In the rat placenta several members of the PRL family gene are expressed during the late pregnancy. However, the full spectrum of their expression mechanisms and regulatory factors are not elucidated yet. Present study aimed to investigate the local expression of the melatonin receptor la(Me $l_{la}$ ) gene and the effect of melatonin on expression of prolactin-like protein A(PLP-A), a member of the PRL-family gene in the rat placenta. According to the RT-PCR, northern blot and in situ hybridization experiments, Me $l_{la}$ gene was locally expressed in the rat placenta, Me $l_{la}$ mRNA was localized mainly in the placental junctional and labyrinth zones. Interestingly, junctional zone of the placenta showed strong expression of Me $l_{la}$ at daytime(16:00) than at nighttime(22:00). Melatonin agonist, chlorornelatonin decreased the PLP-A mRNA levels in the rat placenta. These results suggest that melatonin coupled with Me $l_{la}$ , may act as a regulation factor that mediates the expression of the PLP-A gene in the rat placenta.

• The Journal of Korean Obstetrics and Gynecology
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• v.24 no.3
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• pp.14-27
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• 2011

Objectives: This study was designed to investigate the effects of Acanthopanacis Cortex Radicis extract(ACRE) on the apoptosis in HeLa cell and MCF-7 cell. Methods: After treatment with various concentration of ACRE, cell growth was evaluated in HeLa cell and MCF-7 cell. Hoechst 33342 staining was performed to estimate DNA fragment effect of ACRE on the apoptosis in HeLa cell and MCF-7 cell. Annexin V/PI apoptosis assay was used to estimate the effects of ACRE on the early apoptosis in HeLa cell and MCF-7 cell. RT-PCR was used to estimate the apoptosis gene expression effect of ACRE on Hela cell MCF-7 cell. Results: Under $0.1mg/m\ell$ of ACRE, cytotoxic effect was not found per NIH3T3 cell. The viability of HeLa cell and MCF-7 cells was significantly decreased ACRE ($100{\mu}g/m\ell$) in HeLa cell and MCF-7 cell, ACRE ($50{\mu}g/m\ell$) in HeLa cell 3 days after treatment, in MCF-7 cell 1&3 days after treatment (p<0.01). DNA fragmentation was observed 3 days after treatment of cl of ACRE on HeLa cell and MCF-7 cell. In Annexin V/PI apoptosis assay, after treatment of $100{\mu}g/m\ell$ of ACRE, the early apoptotic cell increased both in HeLa cell and MCF-7 cell. In RT-PCR analysis, after treatment of $100{\mu}g/m\ell$ of ACRE, bcl-2 were decreased and bax, caspase-3 were increased both in HeLa cell and MCF-7 cell. Conclusions: ACRE appears to have considerable activity on the apoptosis in HeLa cell and MCF-7 cell.

• Journal of the Korean Magnetics Society
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• v.16 no.1
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• pp.28-33
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• 2006

La substituted perovskite $BiFeO_3$ have been prepared by a sol-gel method. Magnetic and structural properties of the powders were characterized with Mossbauer spectroscopy, XRD, SEM, and TG-DTA. The crystal structure is found to be a rhombohedrally distorted perovskite structure with the lattice constant $\alpha=3.985{\AA}\;and\;\alpha=89.5^{\circ}.\;Bi_{2/3}La_{1/3}FeO_3$ powders that were annealed at and above $600^{\circ}C$ have a single-phase perovskite structure. However, powders annealed at $900^{\circ}C$ have a typical perovskite structure with small amount of $Bi_2O_3$ phase. The Neel temperature of $Bi_{2/3}La_{1/3}FeO_3$ is found to be $680\pm3K$. The isomer shift value at room temperature is found to be 0.27 mm/s relative to the Fe metal, which is consistent with high-spin $Fe^{3+}$ charge states. Debye temperature far$Bi_{2/3}La_{1/3}FeO_3$ is found to be $305\pm5K$. The average hyperfine field $H_{hf}(T)$ of the $Bi_{2/3}La_{1/3}FeO_3$, shows a temperature dependence of $[H_{hf}(T)-H_{hf}(0)]/H_{hf}(0)=-0.42(T/T_N)^{3/2}-0.13(T/T_N)^{5/2}$ for $T/T_N<0.7$ indicative of spin-wave excitation.