• Journal of the Institute of Electronics and Information Engineers
• /
• v.53 no.11
• /
• pp.66-70
• /
• 2016

This paper presents an 24 GHz I/Q LO generator for a heartbeat measurement radar system. In order to improve the mismatch performance between I and Q LO signals against process variation, a 24 GHz I/Q LO generator employing a low-pass phase shifter and a high-pass phase shifter composed of inductors and capacitors is proposed. The proposed 24 GHz I/Q LO generator consists of an LO buffer, a low-pass phase shifter and a high-pass phase shifter. It was designed using a 65 nm CMOS technology and draws 8 mA from a 1 V supply voltage. The proposed 24 GHz I/Q LO generator shows a gain of 7.5 dB, a noise figure of 2.3 dB, 0.1 dB gain mismatch and $4.3^{\circ}$ phase mismatch between I and Q-path against process and temperature variations for the operating frequencies from 24.05 GHz to 24.25 GHz.

• Nuclear Engineering and Technology
• /
• v.45 no.1
• /
• pp.61-66
• /
• 2013

Among the radioactive wastes generated from the nuclear power plant, a radioactive nuclide such as $^{129}I$ is classified as a difficult-to-measure (DTM) nuclide, owing to its low specific activity. Therefore, the establishment of an analytical procedure, including a chemical separation for $^{129}I$ as a representative DTM, becomes essential. In this report, the adsorption and recovery rate were measured by adding $^{125}I$ as a radio-isotopic tracer ($t_{1/2}$ = 60.14 d) to the simulation sample, in order to measure the activity concentration of $^{129}I$ in a pressurized-water reactor primary coolant. The optimum condition for the maximum recovery yield of iodine on the anion exchange resins (AG1 x2, 50-100 mesh, $Cl^-$ form) was found to be at pH 7. In this report, the effect of the boron content in a pressurized-water reactor primary coolant on the separation process of $^{129}I$ was examined, as was the effect of $^3H$ on the measurement of the activity of iodine. As a result, no influence of the boron content and of the simultaneous $^3H$ presence was found with activity concentrations of $^3H$ lower than 50 Bq/mL, and with a boron concentration of less than 2,000 ${\mu}g/mL$.

• Journal of Life Science
• /
• v.21 no.7
• /
• pp.923-931
• /
• 2011

In the present study, we investigated the effect of indole-3-carbinol (I3C), a natural compound present in vegetables, on the cell migration and invasion of OVCAR-3 ovarian cancer cells. Our results indicated that I3C inhibited the proliferation of OVCAR-3 cells, a process which was associated with inhibition of cell motility as determined by wound healing experiments and cell invasion studies. I3C treatment increased the tightness of the tight junctions (TJs), which was demonstrated by an increase in transepithelial electrical resistance and a decrease in paracellular permeability. The RT-PCR and immunoblotting results indicated that I3C repressed the levels of claudin-3 as well as claudin-4, proteins that comprise a major part of TJs and play a key role in the control and selectivity of paracellular transport. Furthermore, the activities of matrix metalloproteinase (MMP)-2 and MMP-9 were also decreased by treatment with I3C, which was connected with the down-regulation of their mRNAs and protein expression. The results suggest that I3C may be expected to inhibit cancer cell metastasis and invasion by restoring TJs and decreasing MMP activity in ovarian cancer cell line OVCAR-3.

• Journal of Marine Bioscience and Biotechnology
• /
• v.1 no.2
• /
• pp.119-125
• /
• 2006

To understand the comprehensive mechanisms of biological function for insulin-like growth factor-I (IGF-I) in vertebrates, we have investigated the cDNA sequence of this gene in the korean rockfish (Sebastes schlegeli). The mature form of korean rockfish IGF-I was found to be comprised of 67 amino acid residues, showing about a 7 kDa molecular weight. In this study, we used the polymerase chain reaction (PCR) to obtain a korean rockfish IGF-I (KR IGF-I) cDNA fragment, and methods of rapid amplification of cDNA ends (RACE) to obtain a full length of the KR IGF-I sequence. The KR IGF-I encoded for a predicted amino acid sequence showed identities of 93.6 %, 90.7 %, and 85.4 % in comparison with flounder, chinook salmon, and human IGF-I, respectively. To obtain recombinant biologically active polypeptides, korean rockfish B-C-A-D domains were amplified using the PCR, then the isolated cDNA was expressed in the E. coli BL21(DE3). The recombinant KR IGF-I protein biological function was measured by stimulation of [$^3H$] thymidine incorporation, suggesting the cDNA codes for the korean rockfish proIGF-I.

• Journal of the Chungcheong Mathematical Society
• /
• v.26 no.3
• /
• pp.615-623
• /
• 2013

In this paper we establish a central limit theorem for weighted sums of $Y_n={\sum_{i=1}^{n}}a_n,_iX_i$, where $\{a_{n,i},\;n{\in}N,\;1{\leq}i{\leq}n\}$ is an array of nonnegative numbers such that ${\sup}_{n{\geq}1}{\sum_{i=1}^{n}}a_{n,i}^2$ < ${\infty}$, ${\max}_{1{\leq}i{\leq}n}a_{n,i}{\rightarrow}0$ and $\{X_i,\;i{\in}N\}$ is a sequence of linear negatively quadrant dependent random variables with $EX_i=0$ and $EX_i^2$ < ${\infty}$. Using this result we will obtain a central limit theorem for partial sums of linear processes.

• Bulletin of the Korean Mathematical Society
• /
• v.43 no.3
• /
• pp.619-626
• /
• 2006

Let m be any positive integer, R be a ring with identity, $M_m(R)$ be the matrix ring of all m by m matrices eve. R and $G_m(R)$ be the multiplicative group of all n by n nonsingular matrices in $M_m(R)$. In this pape., the following are investigated: (1) for any pairwise coprime ideals ${I_1,\;I_2,\;...,\;I_n}$ in a ring R, $M_m(R/(I_1{\cap}I_2{\cap}...{\cap}I_n))$ is isomorphic to $M_m(R/I_1){\times}M_m(R/I_2){\times}...{\times}M_m(R/I_n);$ and $G_m(R/I_1){\cap}I_2{\cap}...{\cap}I_n))$ is isomorphic to $G_m(R/I_1){\times}G_m(R/I_2){\times}...{\times}G_m(R/I_n);$ (2) In particular, if R is a finite ring with identity, then the order of $G_m(R)$ can be computed.

• Bulletin of the Korean Mathematical Society
• /
• v.33 no.3
• /
• pp.419-425
• /
• 1996

Let ${X, X_n, n \geq 1}$ be a sequence of independent and identically distributed(i.i.d) random variables with EX = 0 and $E$\mid$X$\mid$^p < \infty$ for some $p \geq 1$. Let ${a_{ni}, 1 \leq i \leq n, n \geq 1}$ be a triangular arrary of constants. The almost sure(a.s) convergence of weighted sums $\sum_{i=1}^{n} a_{ni}X_i$ can be founded in Choi and Sung[1], Chow[2], Chow and Lai[3], Li et al. [4], Stout[6], Sung[8], Teicher[9], and Thrum[10].

• The Korean Journal of Physiology and Pharmacology
• /
• v.7 no.5
• /
• pp.283-287
• /
• 2003

While nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) is beneficial for host survival, it is also detrimental to the host. Thus, regulation of iNOS gene expression may be an effective therapeutic strategy for the prevention of unwanted reactions at various pathologic conditions. During the screening process for the possible iNOS regulators, we observed that esculetin is a potent inhibitor of cytokine-induced iNOS expression. The treatment of 3T3-L1 adipocytes with the tumor necrosis factor-${\alpha}$ (TNF) induced iNOS expression, leading to enhanced NO production. TNF-induced NO production was inhibited by esculetin in a dose-dependent manner. Esculetin inhibited the TNF-induced NO production at the transcriptional level through suppression of iNOS mRNA and subsequent iNOS protein expression. These results suggest esculetin, a component of natural products, as a naturally occurring, nontoxic means to attenuate iNOS expression and NO-mediated cytotoxicity.

• Journal of the Korean Statistical Society
• /
• v.7 no.1
• /
• pp.3-10
• /
• 1978

Let $X_i,...,X_n$ be a random sample from a distribution with cumulants $K_1, K_2,...$. The statistic $t = \frac{\sqrt{x}(\bar{X}-K_1)}{S}$ has the well-known 'student' distribution with $\nu = n-1$ degrees of freedom if the $X_i$ are normally distributed (i.e., $K_i = 0$ for $i \geq 3$). An Edgeworth series expansion for the distribution of t when the $X_i$ are not normally distributed is obtained. The form of this expansion is Prob $(t

• Parasites, Hosts and Diseases
• /
• v.22 no.1
• /
• pp.11-20
• /
• 1984

A number of studies on the papillae of cercariae of trematodes reported that the papillar patterns (or chaetotaxy) of cercariae might be an excellent method to attain better understanding of the digenetic trematodes (Richard, 1971 ; Short and Cartrett, 1973; Bayssade-Dufour, 1979) . The present study was aimed to determine the number, distribution pattern and structure of the sensory papillae of Metagonimus yokogawai cercariae, and to elucidate the chaetotaxy of this digenetic trematode. M. yokogawai cercariae were pipetted from a vial in which infected snails (Semisulcospira libertina) had been kept for 3 hours. The snails were collected from an endemic area of M. yokogawai, Boseong river in west-southern part of Korea. Observations of papillae were based on light microscopy of those stained with silver nitrate, and on scanning electron microscopy The results are summarized as follows: 1, All papillae observed were uniciliated. 2. Cilia in anterior tip were shorter than the others in other portions. 3. The body papillae were arranged in essentially symmetrical patterns, Total number of the papillae was 126(63 pairs) in average; anterior tip 40(20 pairs), ventral 20(10 pairs), lateral 42(21 pairs), and caudal 8(4 pairs). 4. The chaetotany of M. yokogawai cercaria was: Ci cycle ($3+3C_{I}V,{\;}2+2C_{I}L,{\;}2+3C_{I}D),{\;}C_{II}{\;}cycle(2C_{II}V,{\;}1C_{II}L,{\;}2C_{II}D),{\;}C_{lll}{\;}cycle{\;}(1+lC_{III}V,{\;}1C_{IlI}L),{\;}C_{IV}{\;}cycle{\;}(1C_{IV}V,{\;}IC_{lV}L){\;}in{\;}cephalic{\;}region:{\;}A_I(1A_{IV}V,{\;}1+2A_{I}L,{\;}1A_{I}D),{\;}A_{II}(1A_{II}V,{\;}1+3A_{II}L,{\;}1A_{II}D),{\;}A_{III}(1A_{III}V,{\;}1+1A_{III}L,{\;}1A_{III}D){\;}and{\;}A_{IV}(1A_{IV}V,{\;}2A_{IV}L)$ in antacetabular region: $1M_{I}V{\;}and{\;}2M_{I}L$ in median: $1+1P_{I}L,{\;}1P_{II}L,{\;}1P_{II}D,{\;}1P_{III}L,{\;}1P_{IV}L{\;}and{\;}1P_{IV}D$ in postacetabular region: 2-2-2-2 in caudal region.