• Journal of Sericultural and Entomological Science
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• v.40 no.2
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• pp.126-130
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• 1998

A noninsecticidal strain, Bacillus thuringiensis NTB-88, isolated from Korean soil, had a typical bipyramidal parasporal inclusion and its serotype is identical to B. thuringiensis subspmorrisoni (H8a8b). To elucidate differences between insecticidal and noninsecticidal strains, we compared strain NTB-88 to other toxic B. thuringiensis subsp. morrisoni strains (HD-12 and PG-14). Restriction endonucleases digested plasmid DNA patterns showed that strain NTB-88 was different from lepidopteran-toxic strain, HD-12, but it was similar to dipteran-toxic strain, PG-14. The gene type of strain NTB-88 was different from those of other insecticidal strains, Furthermore, the NH2-terminal amino acid sequence of crystal protein of strain NTB-88 had no relation to those of the previously known $\delta$-endotoxins in other toxic strains as well as HD-12 and PG-14 strains. Therefore, the noninsecticidal crystal protein in strain NTB-88 is novel and its property is different from insecticidal ones.

• Plant Biotechnology Reports
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• v.4 no.1
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• pp.37-48
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• 2010

[ ${\Delta}^1$ ]pyrroline-5-carboxylate synthetase (P5CS) is a proline biosynthetic pathway enzyme and is known for conferring enhanced salt and drought stress in transgenics carrying this gene in a variety of plant species; however, the wild-type P5CS is subjected to feedback control. Therefore, in the present study, we used a mutagenized version of this osmoregulatory gene-P5CSF129A, which is not subjected to feedback control, for producing transgenic indica rice plants of cultivar Karjat-3 via Agrobacterium tumefaciens. We have used two types of explants for this purpose, namely mature embryo-derived callus and shoot apices. Various parameters for transformation were optimized including antibiotic concentration for selection, duration of cocultivation, addition of phenolic compound, and bacterial culture density. The resultant primary transgenic plants showed more enhanced proline accumulation than their non-transformed counterparts. This proline level was particularly enhanced in the transgenic plants of next generation ($T_1$) under 150 mM NaCl stress. The higher proline level shown by transgenic plants was associated with better biomass production and growth performance under salt stress and lower extent of lipid peroxidation, indicating that overproduction of proline may have a role in counteracting the negative effect of salt stress and higher maintenance of cellular integrity and basic physiological processes under stress.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.113.2-113.2
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• 2011

We observed a low-mass pre-main sequence star, HBC722 (also known as $LkH{\alpha}$ 188 G4), with Camera for QUasars in EArly uNiverse (CQUEAN) attached to 2.1 Otto Struve telescope at McDonald Observatory, USA. HBC722 is a new FU orionis-type object in the direction of NGC7000/IC5070, which produced large amplitude optical outbursts (${\delta}V$=4.7 mag over one year) for a few months and reached the peak in 2010 September. We carried out the photometric observation in SDSS r,i, and z band in 2011 April, July and August to monitor the long term decrease of its brightness. We also made continuous observation in r-band for half night in July, and whole two nights in August to investigate short term variability which could be related to the rotation of the central star or the inner circumstellar disk. In this poster, we present a preliminary result of the photometric observation for HBC722.

• Journal of Magnetics
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• v.16 no.4
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• pp.457-460
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• 2011

In this paper, magnetic property and magnetocaloric effect (MCE) in perovskite manganites of the type $La_{(0.75-X)}Ce_XCa_{0.25}MnO_3$ (x = 0.0, 0.2, 0.3 and 0.5) synthesized by using the standard solid state reaction method have been reported. From the magnetic measurements as a function of temperature and applied magnetic field, we have observed that the Curie temperature ($T_C$) of the prepared samples strongly dependent on Ce content and was found to be 255, 213 and 150 K for x = 0.0, 0.2 and 0.3, respectively. A large magnetocaloric effect in vicinity of $T_C$ has been observed with a maximum magnetic entropy change (${\mid}{\Delta}S_M{\mid}_{max}$) of 3.31 and 6.40 J/kgK at 1.5 and 4 T, respectively, for $La_{0.55}Ce_{0.2}Ca_{0.25}MnO_3$. In addition, relative cooling power (RCP) of the sample under the magnetic field variation of 1.5 T reaches 59 J/kg. These results suggest that $La_{0.55}Ce_{0.2}Ca_{0.25}MnO_3$ compound could be a suitable candidate as working substance in magnetic refrigeration at 213 K.

• Earthquakes and Structures
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• v.9 no.6
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• pp.1133-1152
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• 2015

A frequency-domain method is developed for evaluating the earthquake input energy to two building structures connected by viscous dampers. It is shown that the earthquake input energies to respective building structures and viscous connecting dampers can be defined as works done by the boundary forces between the subsystems on their corresponding displacements. It is demonstrated that the proposed energy transfer function is very useful for clear understanding of dependence of energy consumption ratios in respective buildings and connecting viscous dampers on their properties. It can be shown that the area of the energy transfer function for the total system is constant regardless of natural period and damping ratio because the constant Fourier amplitude of the input acceleration, relating directly the area of the energy transfer function to the input energy, indicates the Dirac delta function and only an initial velocity (kinetic energy) is given in this case. Owing to the constant area property of the energy transfer functions, the total input energy to the overall system including both buildings and connecting viscous dampers is approximately constant regardless of the quantity of connecting viscous dampers. This property leads to an advantageous feature that, if the energy consumption in the connecting viscous dampers increases, the input energies to the buildings can be reduced drastically. For the worst case analysis, critical excitation problems with respect to the impulse interval for double impulse (simplification of pulse-type impulsive ground motion) and multiple impulses (simplification of long-duration ground motion) are considered and their solutions are provided.

• YAKHAK HOEJI
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• v.45 no.1
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• pp.116-124
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• 2001

Nitric oxide is a labile, gaseous, broad spectrum second messenger that used in various tissues and cells. If it is induced by endogenously and exogenously in the neuronal cells, it is able to mediate analgesia or hyperalgesia at the periphery and in the spinal level respectively. This dual role of nitric oxide in the sensory system is very intriguing but has not been fully understood yet. In this experiment, acetylcholine (300 $\mu$g/paw), sodium nitroprusside (600 $\mu$g/paw), and L-arginine (300 $\mu$g/paw) represented antinociceptive effect to noxious topical stimulus, but pronociceptive responses followed by spinally application (20$\mu$g/5$\mu$l, 10$\mu$g/3$\mu$l, 500$\mu$g/5$\mu$l respectively). Calcium ion is critical element which activates nitric oxide synthase, therefore verapamil (300 $\mu$g/paw) and NOS inhibitor (20 mg/kg, L-NAME or L-NOArg) are injected into right hind paw (i.pl.). When verapamil is combined with NOS inhibitors analgesic effects through NO-cGMP pathway are inhibited as compared with ACh alone. Diluted formalin (2.5%), when injected into rats'hind paw (0.05 ml), elicited a biphasic algesic responses and nitric oxide had an analgesic effect on both $A\delta$ and C sensory nerve fibers which manipulate the phases respective1y. Nitric oxides, which produced from constitutive nitric oxide synthase, activated cyclooxygenase-type I and then prostaglandins are produced from them. So, indomethacin and ibuprofen, inhibitors of COX$_1$enzyme, when pretreated intraperitoneally (100 mg/kg) could reduce the hyperalgesic state. From these results, it is possible to imagine that the intrathecally administered NO donors expressed hyperalgesia through both long-term potentiation mechanism and arachidonic acid-prostaglandin cascade.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.70.1-70.1
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• 2012

In-situ X-ray photoelectron spectroscopy (XPS) and infrared (IR) spectroscopy studies of SOFC cathode materials will be discussed in this presentation. The mixed conducting perovskites (ABO3) containing rare and alkaline earth metals on the A-site and a transition metal on the B-site are commonly used as cathodes for solid oxide fuel cells (SOFC). However, the details of the oxygen reduction reaction are still not clearly understood. The information about the type of adsorbed oxygen species and their concentration is important for a mechanistic understanding of the oxygen incorporation into these cathode materials. XPS has been widely used for the analysis of adsorbed species and surface structure. However, the conventional XPS experiments have the severe drawback to operate at room temperature and with the sample under ultrahigh vacuum (UHV) conditions, which is far from the relevant conditions of SOFC operation. The disadvantages of conventional XPS can be overcome to a large extent with a "high pressure" XPS setup installed at the BESSY II synchrotron. It allows sample depth profiling over 2 nm without sputtering by variation of the excitation energy, and most importantly measurements under a residual gas pressure in the mbar range. It is also well known that the catalytic activity for the oxygen reduction is very sensitive to their electrical conductivity and oxygen nonstoichiometry. Although the electrical conductivity of perovskite oxides has been intensively studied as a function of temperature or oxygen partial pressure (Po2), in-situ measurements of the conductivity of these materials in contact with the electrolyte as a SOFC configuration have little been reported. In order to measure the in-plane conductivity of an electrode film on the electrolyte, a substrate with high resistance is required for excluding the leakage current of the substrate. It is also hardly possible to measure the conductivity of cracked thin film by electrical methods. In this study, we report the electrical conductivity of perovskite $La_{0.6}Sr_{0.4}CoO_{3-{\delta}}$ (LSC) thin films on yttria-stabilized zirconia (YSZ) electrolyte quantitatively obtained by in-situ IR spectroscopy. This method enables a reliable measurement of the electronic conductivity of the electrodes as part of the SOFC configuration regardless of leakage current to the substrate and cracks in the film.

• Animal cells and systems
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• v.1 no.4
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• pp.589-594
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• 1997

The neuronal voltage-sensitive calcium channels (VSCCs) are multisubunit complexes consisting of $\alpha_1,\;\alpha_2-\delta$ and $\beta$ subunits. Heterologous expression and biochemical studies have shown that the activity of VSCCs is regulated by their $\beta$ subunits in a $\beta$ subunit isoform-specific manner. To elucidate the $\beta$ subunit identity of the P/Q-type calcium channel encoded by an $\alpha_{1A}$ subunit, which is exclusively expressed in the Purkinje and granule cell of the cerebellum, we have examined the spatial and temporal expression patterns of $\beta$ subunits and compared them with those of $\alpha_{1A}$ subunit in the developing rat cerebellum. Reverse transcriptase- polymerase chain reaction (RT-PCR) and Northern blot analysis have shown that $\beta_4$ subunit mRNA was prominently expressed in the cerebellum and much more abundant than any other distinct $\beta$ subunits. RNase protection assay has further demonstrated that the expression of $\alpha_{1A}$ and $\beta_4$ subunits increased during cerebellar development, while the amount of $\beta_2$ and $\beta_3$ mRNAs did not significantly change. In addition, a $\beta_4$ transcript was present in cultured cerebellar granule cells, but not in astrocyte cells, and the level of $\beta_4$ mRNA expression increased gradually in vitro seen as in vivo. Based on the spatial and temporal expression patterns of $\beta_4$ subunit, we conclude that $\beta_4$ may predominantly associate, but probably not exclusively, with the $\alpha_{1A}$ subunit in rat cerebellar granule cells.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.41.3-42
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• 2016

New CCD photometric observations of GX Aur have been made between 2004 and 2015. Our light curves are the first ever compiled and display the variable O'Connell effect. The light variations are satisfactorily modeled by including time-varying cool-spots on the component stars. Our light curve synthesis indicates that the eclipsing pair is an A-type contact binary with parameters of i = 81.1 deg, ${\Delta}T=36K$, q = 0.950 and f = 46%. Including our 25 timing measurements, a total of 83 times of minimum light spanning about 66 yr were used for a period study. It was found that the orbital period of GX Aur has varied due to two periodic oscillations superposed on an upward-opening parabolic variation. The long-term period increase rate is deduced as $+9.636{\times}10^{-10}d\;yr^{-1}$, which can be produced as a mass transfer from the secondary star to the primary at a rate of $3.136{\times}10^{-6}M_{\odot}\;yr^{-1}$, among the largest rates for contact systems. The periods and semi-amplitudes of the two periodic variations are about $P_3=8.7yr$ and $P_4=21.2yr$, and $K_3=0.011d$ and $K_4=0.017d$, respectively. The most reasonable explanation for both cycles is a pair of light-travel-time effects driven by the possible existence of an unseen third and fourth components with projected masses of $M_3=0.91M_{\odot}$ and $M_4=1.09M_{\odot}$ in eccentric orbits of $e_3=0.13$ and $e_4=0.73$. Because no third light was detected in the light curve synthesis, each circumbinary object could be a compact star or a binary itself.

• Transactions on Electrical and Electronic Materials
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• v.10 no.6
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• pp.217-221
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• 2009

The use of the carbon nanotube (CNT) is superior to the general powder state materials in their thermal and chemical properties. Because its ratio of diameter to length (aspect ratio) is very large, it is known to be a type of ideal nano-reinforcement material. Based on this advantage, the existing carbon black of the semiconductive shield materials used in power cables can acquire excellent properties by the use of a small amount of CNTs. Therefore, we fabricated specimens using a solution mixing method. We investigated the thermal properties of the CNT, such as its storage modulus, loss modulus, and its tan delta using a dynamic mechanical analysis 2980. We found that a high thermal resistance level is demonstrated by using a small amount of CNTs. We also investigated the chemical properties of the CNT, such as the oxidation reaction by using Fourier transform infrared spectroscopy (FT-IR) made by Travel IR. In the case of the FT-IR tests, we searched for some degree of oxidation by detecting the carboxyl group (C=O). The results confirm a tendency for a high cross-linking density in a new network in which the CNTs situated between the carbon black constituent molecules show a bond using similar constructive properties.