• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.3
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• pp.111-114
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• 2005

Organic monolayers were fabricated onto Au(l l l) substrate by self-assembly method using dipyridinium. Also, organic single molecule in the organic monolayers was selected to measure the current-voltage (I-V) curves by using the ultrahigh vacuum scanning tunneling microscopy (UHV-STM). The organic molecule used in the experiment was dipyridinium dithioacetate, which contains thiol functional group and can be self-assembled easily onto Au(l l l) substrate. The concentration of dipyridinium dithioacetate for self-assembly procedure was I [mM/L]. To confirm the formation of self-assembled mono layers (SAMs), the differences of thickness of the self-assembled organic monolayers were observed by using an ellipsometer, and the morphology and I-V curves of the SAMs were investigated by using UHV-STM. The applied voltages were from -2 [V] to +2 [V], temperature was 300 [K]. The vacuum for measuring current of the organic single molecule was 6 $\times$ 10$^{-8}$ [Torr]. As a result, properties of the negative differential resistance (NDR) in constant voltage were found.

• Journal of Life Science
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• v.19 no.11
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• pp.1529-1537
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• 2009

To elucidate further the antitumor effects of a natural L-arginine analogue, L-canavanine, the mechanism underlying apoptogenic activity of L-canavanine and its modulation by protein tyrosine kinase $p56^{lck}$ was investigated in human Jurkat T cells. When the cells were treated with 1.25 to 2.5 mM L-canavanine for 36 h, several apoptotic events including mitochondrial membrane potential (${\Delta\Psi}m$) loss, activation of caspase-9, -3, -8, and -7, poly (ADP-ribose) polymerase (PARP) degradation, and DNA fragmentation were induced without alteration in the levels of Fas or FasL. These apoptotic changes were more significant in $p56^{lck}$-deficient Jurkat clone JCaM1.6 than in $p56^{lck}$-positive Jurkat clone E6.1. The L-canavanine-induced apoptosis observed in $p56^{lck}$-deficient JCaM1.6 cells was significantly reduced by introducing $p56^{lck}$ gene into JCaM1.6 cells by stable transfection. Treatment of JCaM1.6/lck cells with L-canavanine caused a transient 1.6-fold increase in the kinase activity of $p56^{lck}$. Both FADD-positive wild-type Jurkat T cell clone A3 and FADD-deficient Jurkat T cell clone I2.1 exhibited a similar susceptibility to the cytotoxicity of L-canavanine, excluding involvement of Fas/FasL system in triggering L-canavanine-induced apoptosis. The L-canavanine-induced apoptotic sub-$G_1$ peak and activation of caspase-3, -8, and -7 were abrogated by pan-caspase inhibitor (z-VAD-fmk), whereas L-canavanine-induced activation of caspase-9 was not affected. These results demonstrated that L-canavanine caused apoptosis of Jurkat T cells via the loss of ${\Delta\Psi}m$, and the activation of caspase-9, -3, -8, and -7, leading to PARP degradation, and that the $p56^{lck}$ kinase attenuated the ${\Delta\Psi}m$ loss and activation of caspases, and thus contributed as a negative regulator to L-canavanine-induced apoptosis.

• Journal of Microbiology
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• v.40 no.3
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• pp.183-192
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• 2002

Cells infected With equine herpesvirus type-1 (EHV-1) Produced both infectious and non-infectious Virus-related particles. Compared to the whole virion, non-infectious particles termed L-particles were deter-mined to lack 150 kDa protein, commonly known as nucleocapsid protein. The potential of L-particles to induce immune responses was studied in mice and foals. Intranasal immunization with L-particles or whole virions induced poor IgG antibody responses in mice. Interestingly, despite the poor antibody response, the conferred immunity protected the host from challenge infections. This was indicated by a significant reduction in virus titers in line with recovery towards normal body weight. Subsequently, the test on the usefulness of L-particles as immunizing agents was extended to foals. Immunization of specific-pathogen-free (SPF) foals resulted in similar results. As determined by a complement-fixing-antibody test (CFT), foals seroconverted when they were immunized either with inactivated L-particles or whole virions via intramuscular (i.m.) injections. The presence of the antibody correlated with the degree of protection. Beyond day 1 post challenge infection (p.i.), there was no virus shedding in the nasal mucus of foals immunized with whole EHV-1 virions. Virus shedding was observed in foals Immunized with L-particles but limited to days 6 to 8 p.i. only. In contrast, extended vim shedding was observed in non-immunized foals and it was well beyond day 14 p.i. Viremia was not detected for more than four days except in non-immunized foals. Immunization in mice via intranasal (i.n.) conferred good protection. However, compared to the i.n. route, a greater degree of protection was obtained in foals following immunization via i.m. route. Despite variation in the degree of protection due to different routes of immunization in the two animal species, our results have established significant evidence that immunization with L-particles confers protection in the natural host. It is suggested that non-infectious L-particles should be used as immunizing agents for vaccination of horses against EHV-1 infection.

• Journal of Ginseng Research
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• v.27 no.3
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• pp.146-150
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• 2003

This study was carried out to obtain basic information on breeding using PCR-aided RFLP technology which can identify the variation inter- and intra-species of ginseng in the level of DNA. It was intended to investigate banding pattern on psbA and rbeL genes of chloroplast DNA in ginseng after treating with restriction enzymes. To isolate psbA and rbcL genes of chloroplast, both psbA-N, psbA-C primer and rbcL-N, PX-1 primer were used. As a result, 1,008 bp band of psbA gene and 1,336 bp band of rbcL gene were appeared, which was optimal and expected molecular weight. In addition, primers to isolate atpB, rpoB, trnL, and trnF genes were used, resulting in the expected 1366, 900, 1500 and 1008 bp bands. Genes of psbA and rbcL isolated by PCR were cut by restriction enzymes, Sau3A, TaqI, AluI, HaeIII, and RFLP pattern was investigated. KG line and other species of ginseng were cut by TaqI treatment, and bands were located in 800 bp. The treatment treated by AluI also showed the same 800 bp band in KG line and other species. In HaeIII treatment, 500 bp of faint bands were shown in case of KG line, whereas any bands were not observed in other species. All chloroplast genes formed bands by PCR amplification. However, it was not evident to distinguish intra-or inter-species of ginseng after restriction enzyme treatment. Therefore, more restriction enzyme treatment or sequence comparison method should be considered for further experiment.

• Korean Journal of Plant Resources
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• v.23 no.6
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• pp.513-518
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• 2010

In the present study, the antinociceptive profiles of Dianthus chinensis L extract were examined in ICR mice. Dianthus chinensis L extract administered orally (200 mg/kg) showed an antinociceptive effect as measured by the tail-flick and hot-plate tests. In addition, Dianthus chinensis L extract attenuated the writhing numbers in the acetic acid-induced writhing test. Furthermore, the cumulative nociceptive response time for intrathecal (i.t.) injection of substance P ($0.7\;{\mu}g$) was diminished by Dianthus chinensis L extract. Intraperitoneal (i.p.) pretreatment with yohimbine ($\alpha_2$-adrenergic receptor antagonist) attenuated antinociceptive effect induced by Dianthus chinensis L extract in the writhing test. However, naloxone (opioid receptor antagonist) or methysergide (5-HT serotonergic receptor antagonist) did not affect antinociception induced by Dianthus chinensis L extract in the writhing test. Our results suggest that Dianthus chinensis L extract shows an antinociceptive property in various pain models. Furthermore, this antinociceptive effect of Dianthus chinensis L extract may be mediated by $\alpha_2$-adrenergic receptor, but not opioidergic and serotonergic receptors.

• Bulletin of the Korean Chemical Society
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• v.2 no.4
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• pp.125-129
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• 1981

The addition reactions of cysteine without blocking amino and carboxyl groups to substituted and unsubstituted ${\beta}$-nitro-styrene derivatives were investigated. ${\beta}$-Nitrostyrene(1a), p-methyl-${\beta}$-nitrostyrene(1b), 3,4,5-trimethoxy-$[\beta}$ -nitrostyrene(1c), $[\varpi}$-3,4-methylenedioxy-${\beta}$ -nitrostyrene(1d), o-, m- and p-chloro-${\beta}$ -nitrostyrene (1e, 1f, 1g) and o-, m- and p-methoxy-${\beta}$-nitrostyrene (1h, 1i, 1j) easily undergo addition reactions with cysteine to form S-(2-nitro-1-phenylethyl)-L-cysteine(3a), S-[2-nitro-1-(p-methyl)phenyl-ethyl]-L-cysteine(3b), S-[2-nitro-1-(3',4',5'-trimethoxy) phenylethyl]-L-cysteine(3c), S-[2-nitro-1-($[\vatpi}$ -3',4'-methylenedioxy)phenylethyl]-L-cysteine(3d), S-[2-nitro-1-(o-chloro)phenylethyl]-L-cysteine(3e), S-[2-nitro-1-(m-chloro)-phenylethyl]-L-cysteine(3f), S-[2-nitro-1-(p-chloro)phenylethyl]-L-cysteine(3g), S-[2-nitro-1-(o-methoxy)phenylethyl]-L-cysteine(3h), S-[2-nitro-1-(m-methoxy)phenylethyl]-L-cysteine(3i) and S-[2-nitro-1-(p-methoxy)phenylethyl]-L-cysteine(3j), respectively. The structure of adducts were confirmed by means of UV-spectrum, IR-spectrum, molecular weight measurement and elemental analysis. The various factors effecting the yield of cysteine adducts to ${\beta}$-nitrostyrene derivatives were also studied.

• Journal for History of Mathematics
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• v.24 no.4
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• pp.1-6
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• 2011

We investigate a method to find the least common multiples of numbers in the mathematics book GuIlJib(구일집(九一集), 1724) written by the greatest mathematician Hong Jung Ha(홍정하(洪正夏), 1684~?) in Chosun dynasty and then show his achievement on Number Theory. He first noticed that for the greatest common divisor d and the least common multiple l of two natural numbers a, b, l = $a\frac{b}{d}$ = $b\frac{a}{d}$ and $\frac{a}{d}$, $\frac{b}{d}$ are relatively prime and then obtained that for natural numbers $a_1,\;a_2,{\ldots},a_n$, their greatest common divisor D and least common multiple L, $\frac{ai}{D}$($1{\leq}i{\leq}n$) are relatively prime and there are relatively prime numbers $c_i(1{\leq}i{\leq}n)$ with L = $a_ic_i(1{\leq}i{\leq}n)$. The result is one of the most prominent mathematical results Number Theory in Chosun dynasty. The purpose of this paper is to show a process for Hong Jung Ha to capture and reveal a mathematical structure in the theory.

• Journal of Preventive Medicine and Public Health
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• v.40 no.1
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• pp.71-76
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• 2007

Objectives : This study was performed to investigate the distribution of apolipoproteins A-I and B among Korean employees and their partners. Methods : The study population consisted of 7,633 men and women (4,578 men and 3,054 women) residing in Seoul and Kyung-gee Do, with an average age of $43.5{\pm}8.3$ years. Blood samples were collected following at least 12 hours of fasting. Apolipoproteins A-I and B were measured using a Behring Nephelometer analyzer. The body mass index (BMI) for each participant was calculated as weight (kg) divided by height squared $(m^2)$. Information on health-related behaviors such as exercise, alcohol intake, and smoking habits was collected through self-administrated questionnaires. Results : The mean concentrations of Apo A-I were $132.6{\pm}22.3mg/dL$ and $142.9{\pm}24.8mg/dL$ in the men and women, respectively. The concentration of Apo A-I increased significantly across all age categories of men. The mean concentrations of Apo B were $101.7{\pm}23.2mg/dL$ and $87.8{\pm}23.5mg/dL$ in the men and women, respectively, and Apo B increased significantly across all age categories for both the men and women. Exercise and BMI were major determinants for Apo A-I and B levels. The 10th percentile of Apo A-I concentration was 109 mg/dL in the men and 113 mg/dL in the women, and the 90th percentile of Apo B concentration was 131 mg/dL in the men and 118 mg/dL women. Conclusions : For the prevention of coronary artery disease, we recommend that for individuals in the 10th percentile of concentration for Apo A-I and the 90th percentile of concentration for Apo B, active preventive interventions such as weight loss and exercise should be taken. This study, within its limitations, may be useful for evaluating apolipoprotein A-I and B concentrations in Korean adults.

• Proceedings of the KIEE Conference
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• 1988.11a
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• pp.329-332
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• 1988

In this paper, A analysis method about air gap field of L.I.M. considering Transverse Edge Effect is suggested. Especially, the case of displacement of primary and secondary it can be analysed and criteria for design of L. I. M. is proposed by proving the influance of ratio of width for primary and secondary to the characteristic

• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.4
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• pp.24-32
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• 1985

This paper presents the design method for multivalued logic functions using $I^2L$ circuits. First, the a비orithm that transforms delta functions into discrete functions of a truncated difference is obtained. The realization of multivalued logic circuits by this algorithm is discussed. And then, the design method is achieved by mixing discrete functions and delta functions using the modified algorithm for given multivalued truth tables. The techniques discussed here are easily extended to multi-input and multi-output logic circuits.