• ETRI Journal
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• v.30 no.4
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• pp.526-534
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• 2008

This paper presents a fully integrated 0.13 ${\mu}m$ CMOS MB-OFDM UWB transmitter chain (mode 1). The proposed transmitter consists of a low-pass filter, a variable gain amplifier, a voltage-to-current converter, an I/Q up-mixer, a differential-to-single-ended converter, a driver amplifier, and a transmit/receive (T/R) switch. The proposed T/R switch shows an insertion loss of less than 1.5 dB and a Tx/Rx port isolation of more than 27 dB over a 3 GHz to 5 GHz frequency range. All RF/analog circuits have been designed to achieve high linearity and wide bandwidth. The proposed transmitter is implemented using IBM 0.13 ${\mu}m$ CMOS technology. The fabricated transmitter shows a -3 dB bandwidth of 550 MHz at each sub-band center frequency with gain flatness less than 1.5 dB. It also shows a power gain of 0.5 dB, a maximum output power level of 0 dBm, and output IP3 of +9.3 dBm. It consumes a total of 54 mA from a 1.5 V supply.

• Kyungpook Mathematical Journal
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• v.54 no.3
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• pp.387-399
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• 2014

We show that in quasi-topological spaces, separation axiom $T_2$ is equivalent to ${\alpha}-T_2$, $T_0$ is equivalent to semi - $T_0$, and semi - $T_{\frac{1}{2}}$ is equivalent to semi - $T_D$. Also, we give characterizations for ${\alpha}-T_1$, semi - $T_1$ and semi - $T_{\frac{1}{2}}$ generalized topological spaces.

• Bulletin of the Korean Chemical Society
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• v.34 no.7
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• pp.2117-2124
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• 2013

The binding properties and sequence selectivities of ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ (bip = 4,4'-biphenylene (imidazo [4,4-f][1,10]phenanthroline) complexes with $poly[d(A-T)_2]$ and $poly[d(G-C)_2]$ were investigated using conventional spectroscopic methods. When bound to $poly[d(A-T)_2]$, a large positive circular dichroism (CD) spectrum was induced in absorption region of the bridging moiety for both the ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complexes, which suggested that the bridging moiety sits in the minor groove of the polynucleotide. As luminescence intensity increased, decay times became longer and complexes were well-protected from the negatively charged iodide quencher compared to that in the absence of $poly[d(A-T)_2]$. These luminescence measurements indicated that Ru(II) enantiomers were in a less polar environment compared to that in water and supported by minor groove binding. An angle of $45^{\circ}$ between the molecular plane of the bridging moiety of the ${\Delta}{\Delta}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complex and the local DNA helix axis calculated from reduced linear dichroism ($LD^r$) spectrum further supported the minor groove binding mode. In the case of ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complex, this angle was $55^{\circ}$, suggesting a tilt of DNA stem near the binding site and bridging moiety sit in the minor groove of the $poly[d(A-T)_2]$. In contrast, neither ${\Delta}{\Delta}$-nor ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complex produced significant CD or $LD^r$ signal in the absorption region of the bridging moiety. Luminescence measurements revealed that both the ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complexes were partially accessible to the $I^-$ quencher. Furthermore, decay times became shorter when bis-Ru(II) complexes bound to $poly[d(G-C)_2]$. These observations suggest that both the ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complexes bind at the surface of $poly[d(G-C)_2]$, probably electrostatically to phosphate group. The results indicate that ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ are able to discriminate between AT and GC base pairs.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1529-1536
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• 2006

We cloned a gene of ompH(D:4) from pigs infected with P. multocida D:4 in Korea [16]. The gene is composed of 1,026 nucleotides coding 342 amino acids (aa) with a signal peptide of 20 aa (GenBank accession number AY603962). In this study, we analyzed the ability of the ompH(D:4) to induce protective immunity against a wild-type challenge in mice. To determine appropriate epitope(s) of the gene, one full and three different types of truncated genes of the ompH(D:4) were constructed by PCR using pET32a or pRSET B as vectors. They were named ompH(D:4)-F (1,026 bp [1-1026] encoding 342 aa), ompH(D:4)-t1 (693 bp [55-747] encoding 231 aa), ompH(D:4)-t2 (561 bp [187-747] encoding 187 aa), and ompH(D:4)-t3 (540 bp [487-1026] encoding 180 aa), respectively. The genes were successfully expressed in Escherichia coli BL21(DE3). Their gene products, polypeptides, OmpH(D:4)-F, -t1, -t2, and -t3, were purified individually using nickel-nitrilotriacetic acid (Ni-NTA) affinity column chromatography. Their $M_rs$ were determined to be 54.6, 29, 24, and 23.2 kDa, respectively, using SDS-PAGE. Antisera against the four kinds of polypeptides were generated in mice for protective immunity analyses. Some $50{\mu}g$ of the four kinds of polypeptides were individually provided intraperitoneally with mice (n=20) as immunogens. The titer of post-immunized antiserum revealed that it grew remarkably compared with pre-antiserum. The lethal dose of the wild-type pathogen was determined at $10{\mu}l$ of live P. multocida D:4 through direct intraperitoneal (IP) injection, into post-immune mice (n=5, three times). Some thirty days later, the lethal dose ($10{\mu}l$) of live pathogen was challenged into the immunized mouse groups [OmpH(D:4)-F, -t1, -t2, and -t3; n=20 each, two times] as well as positive and negative control groups. As compared within samples, the OmpH(D:4)-F-immunized groups showed lower immune ability than the OmpH(D:4)-t1, -t2, and -t3. The results show that the truncated-OmpH(D:4)-t1, -t2, and -t3 can be used for an effective vaccine candidate against swine atrophic rhinitis caused by pathogenic P. multocida (D:4) isolated in Korea.

• Journal of Nutrition and Health
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• v.30 no.10
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• pp.1195-1202
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• 1997

Iodine-rich seaweed soup has been traditionally supplied to postpartum women in Korea. This dietary habit might introduce over-intake of iodine above the recommended requirements, and might provoke postpartum thyroid dysfunction. Although the response to excess iodine intake is highly variable, goiter, hyperthyroidism, hypothyroidism, and thyroiditis could follow the daily intake of 1,500$\mu\textrm{g}$ of iodine. A few studies are available concerning iodine toxicity in Korea. The purpose of this study was to investigate the relationships between the dietary intake of iodine and thyroid function change as well as the incidence of postpartum thyroiditis. One hundred and thirty-seven postpartum women who had experienced normal deliveries were studied. Dietary intake of iodine and excretion concentration of iodine in breast milk and maternal urine were measured . Serum T$_3$, T$_4$, TSH, anti-thyroglobulin antibody, and anti-microsomal antibody were anlayzed 1 week before delivery and 1, 6, 12, and24 weeks after delivery. Iodine intake was analyzed by one-to-one interviews using 24-hr recall and a food frequncy questionnaire. The result showed that the intake of dietary iodine before delivery and 1 and24 weeks after delivery were 483$\mu\textrm{g}$/day, 3367$\mu\textrm{g}$/day, and 1069$\mu\textrm{g}$/day, respectively. The concentration of iodine in urine at the first week after delivery was 63$\mu\textrm{g}$/dL, and 23.9$\mu\textrm{g}$/dL in breast milk . The levels of serum T$_3$ and T$_4$ before delivery were 2.01ng/mL and 11.49$\mu\textrm{g}$U/dL, respectively, showing that the levels were gradually dropping to normal values after delivery. Positive serum anti-thyroglobulin antibody and anti-microsomal antibody appeared in 3 cases. After a 24 week follow-up period , 6 women(10.3%) experienced cases of postpartum thyroiditis, 5 of which were cases of hyperthyroidism and one of which was a case of hypothyroidism. These figures of postpartum thyroiditis are similar to those of other countries.

• Communications of the Korean Mathematical Society
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• v.9 no.4
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• pp.881-889
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• 1994

Let ($X, \Beta, \mu$) be a measure space with the $\sigma$-algebra $\Beta$ and the probability measure $\mu$. Throughouth this article set equalities and inclusions are understood as being so modulo measure zero sets. A transformation T defined on a probability space X is said to be measure preserving if $\mu(T^{-1}E) = \mu(E)$ for $E \in B$. It is said to be ergodic if $\mu(E) = 0$ or i whenever $T^{-1}E = E$ for $E \in B$. Consider the sequence ${x, Tx, T^2x,...}$ for $x \in X$. One may ask the following questions: What is the relative frequency of the points $T^nx$ which visit the set E\ulcorner Birkhoff Ergodic Theorem states that for an ergodic transformation T the time average $lim_{n \to \infty}(1/N)\sum^{N-1}_{n=0}{f(T^nx)}$ equals for almost every x the space average $(1/\mu(X)) \int_X f(x)d\mu(x)$. In the special case when f is the characteristic function $\chi E$ of a set E and T is ergodic we have the following formula for the frequency of visits of T-iterates to E : $$ lim_{N \to \infty} \frac{$\mid${n : T^n x \in E, 0 \leq n $\mid$}{N} = \mu(E) $$ for almost all $x \in X$ where $$\mid$\cdot$\mid$$ denotes cardinality of a set. For the details, see [8], [10].

• Microbiology and Biotechnology Letters
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• v.11 no.3
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• pp.223-231
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• 1983

The productions of beta-exotoxin from sixteen Bacillus thuringiensis strains were examined by Micrococus flava primarily, and then measured by spectrophotometer during culturing in Conner and Hansen mineral salts medium at 28$^{\circ}C$. Also the toxic effects of the toxin to mice were checked. The growth of Bacillus thuringiensis K2 and BTK2-T1, -T13, -T33 and -T40 got into stationary phase at 6 hour culture and then maintained it up to 48 hours without severe fluctuation. The production of beta-exotoxin from the strains, BTK2, BTK2-T1, -T13, -T17 and -T33 appeared at 6 hour culture and the amounts of the toxin were about 40 $\mu\textrm{g}$/$m\ell$ at 6 hour culture, approximately 70 $\mu\textrm{g}$/$m\ell$ at 12 hours, approximately 85$\mu\textrm{g}$/$m\ell$ from 24 hours to 48 hours. At 48 hour-culture, BTK2 produced 80 $\mu\textrm{g}$/$m\ell$ of beta-exotoxin (5.5$\times$10$^{8}$ cells/$m\ell$, BTK2-T13 produced 84 $\mu\textrm{g}$/$m\ell$ (4.3$\times$10$^{8}$ cells/$m\ell$), BTK2-T17 produced 87$\mu\textrm{g}$/$m\ell$ (1.4$\times$10$^{8}$ cells/$m\ell$), and BTK2-T33 produced 84 $\mu\textrm{g}$/$m\ell$ (4.9$\times$10$^{8}$ cells/$m\ell$). All other serotypes also produced beta-exotoxin. At 48 hour culture, BTK-37 produced 88$\mu\textrm{g}$/$m\ell$ (6.1$\times$10$^{8}$ cells/$m\ell$), BTK-35 produced 81 $\mu\textrm{g}$/$m\ell$), and the rest of them produced less than 70 $\mu\textrm{g}$/$m\ell$. To check the toxicity of beta-exotoxin and B. thuringiensis, the cultured media with microorganisms were inoculated to mice by per os, intraperiloneal, subcutaneous and intracerebral injection, and nasal cavity inoculation for 30 days. However, the toxin did not kill all of the treated mice.

• Journal of the Chungcheong Mathematical Society
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• v.20 no.3
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• pp.333-342
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• 2007

Suppose that ${\mu}$ is a finite positive Borel measure on the unit ball $B{\subset}C^n$. The boundary of B is the unit sphere $S=\{z:{\mid}z{\mid}=1\}$. Let ${\sigma}$ be the rotation-invariant measure on S such that ${\sigma}(S)=1$. In this paper, we will show that if $sup_{{\zeta}{\in}S}\;{\int}_{B}\;P(z,{\zeta})d{\mu}(z)$<${\infty}$ where $P(z,{\zeta})$ is the Poission-Szeg$\ddot{o}$ kernel for B, then ${\mu}$ is a Carleson measure. We will also show that if $sup_{{\zeta}{\in}S}\;{\int}_{B}\;P(z,{\zeta})d{\mu}(z)$<${\infty}$, then the operator T such that T(f) = P[f] is compact as a mapping from $L^p(\sigma)$ into $L^p(B,d{\mu})$.

• Journal of applied mathematics & informatics
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• v.11 no.1_2
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• pp.391-399
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• 2003

Let (X,S,$\mu$) be a measure space and M be the vector space of all real valued S-measurable functions defined on (X,S,$\mu$). For $E\;{\in}\;S$ with $\mu(E)\;<\;{\infty}$, $d_E$ is a pseudometric on M. With the notion of D = {$d_E$\mid$E\;{\in}\;S,\mu(E)\;<\;{\infty}$}, in this paper we investigate some topological structure T of M. Indeed, we shall show that it is possible to define a complete invariant metric on M which is compatible with the topology T on M.

• Journal of Food Hygiene and Safety
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• v.34 no.1
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• pp.58-64
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• 2019

In the current study, 109 commercial nut samples were collected from different Korean markets and analyzed for the contamination of 5 different mycotoxins (aflatoxin, ochratoxin A, deoxynivalenol, zearalenone, and T-2 toxin) using ELISA kits. The results revealed that the most frequently detected mycotoxin was zearalenone (n=36, 33%), followed by aflatoxin (n=31, 28.4%) and ochratoxin A (n=30, 27.5%). Deoxynivalenol and T-2 toxin were also detected in 22 (20.3%) samples, respectively. Among 109 nut samples, 33 samples (30.3%) were contaminated only with one kind of mycotoxin, whereas 43 samples had at least 2 kinds of mycotoxins. Two samples were contaminated with as many as 4 different mycotoxins, and they were both walnuts. Although the monitoring results revealed the amount of aflatoxin contamination was under the safety criteria, there is no current safety guideline for other kinds of mycotoxins or multiple contaminations in Korea. Therefore, further studies should be performed to reveal the distribution of mycotoxin in different foods and propose appropriate safety guidelines for Korean markets.