• Development and Reproduction
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• v.7 no.2
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• pp.119-126
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• 2003

In the previous study, we obtained list of differentially expressed genes between postnatal day 1 and day 5 mouse ovaries using suppression subtractive hybridization(SSH) and found that MT Oansposon-like element, clone MTi7(MTi7) was one of the highly expressed genes in the day 5 mouse ovary(Park et at., 2002). Results of in situ hybridization and RNA interference revealed that the expression of MTi7 is oocyte-specific in the ovary and may be involved in the regulation of oocyte maturation(Park et at., 2003). At present, MTi7 sequence has been known only in the mouse. Therefore, the present study was accomplished 1) to identify MTi7 sequence in the other mammalian species, such as bovine, porcine, rat, and human, and 2) to evaluate the flanking sequence of the mouse MTi7 since it has transposon characteristics. Using ovarian cDNAs derived from low different species, we cloned and identified new MTi7 sequence showing a high degree of sequence homology with the mouse MTi7(87∼98%). By using inverse PCR, we found that the mouse MTi7 may intercalated the beta-carotene 15, 15'-monooxygenase(Bcdo) gene and/or serine protease inhibitor, Kunitz Dpe I(Spint 1) gene. By finding the MTi7 sequences in the other mammalian species and the flanking gene of the MTi7 in mouse, it is expected to reveal the role(s) of MTi7 in the oogenesis as well as folliculogenesis in the near future.

• Clinical and Experimental Reproductive Medicine
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• v.30 no.4
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• pp.299-307
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• 2003

Objectives: The present study was conducted to evaluate the mobile transposon-like element, clone MTi7 (MTi7) expression in the mouse ovary and to determine its role(s) in the mouse oocytes by RNA interference (RNAi). Methods: MTi7 mRNA expression was localized by in situ hybridization in day5 and adult ovaries. Double stranded RNA (dsRNA) was prepared for c-mos, a gene with known function as control, and the MTi7. Each dsRNA was microinjected into the germinal vesicle (GV) stage oocytes then oocyte maturation and intracellular changes were evaluated. Results: In situ hybridization analysis revealed that MTi7 mRNA localized to the oocyte cytoplasm from primordial to preovulatory follicles. After dsRNA injection, we found 43-54% GV arrest of microinjected GV oocytes with 68%-90% decrease in targeted c-mos or MTi7 mRNA. Conclusions: This is the first report of the oocyte-specific expression of the MTi7 mRNA. From results of RNAi for MTi7, we concluded that the MTi7 is involved in the germinal vesicle breakdown in GV oocytes, and MTi7 may be implicated with c-mos for its function. We report here that RNAi provides an outstanding approach to study the function of a gene with unknown functions.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.7
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• pp.576-585
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• 2014

In this paper, we survey the Moving Target Indication(MTI) techniques for small UAVs. MTI consists of image alignment phase and frame differencing correction phase, and image alignment has two ways of parametric approach which is mainly focused in this paper and non-parametric approach. Since small UAVs are operated in the low altitude, the parallax is considerable and the epipolar geometry is applied to compensate the parallax. The related works and future works are presented.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.10
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• pp.1077-1083
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• 2009

To reject the Doppler frequency spectrum dispersion of clutter caused by high-speed antenna rotation of MTI radar system due to terrain characteristics, signal processing parameters(MTI filter constant, M/N detector ration, K-factor and offset of CFAR) are adjusted for the optimal elimination of the ground clutter. For this investigation, logging equipment is designed and utilized for the collection of classified ground clutter data. Test case is devised through Matlab simulation for the classified analysis and optimization of clutter rejection. Then indoor radar test and outside test in accordance with terrain characteristics are repeatedly performed for the verification of the test. This whole process is through the evolutional development model and repeated for the optimization. Final result is that ground-clutter rejection capability is 5.6 times(7.5 dB) better than that of existing radar system.

• Journal of the Korean Ceramic Society
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• v.49 no.3
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• pp.272-278
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• 2012

Effects of ceramics on the microwave dielectric properties of polytetrafluoroethylene (PTFE) composites filled with $MgTiO_3$ (MTi) and/or $MgTa_2O_6$ (MTa) were investigated. The dielectric constant ($K$), quality factor ($Qf$), and temperature coefficient of resonant frequency ($TCF$) of the composites were dependent on the type and volume fraction ($V_f$) of the ceramics. For the composites mixed with MTa and MTi, the $K$ and $TCF$ values decreased with increasing MTi content. The $Qf$ values of the composites were affected by relative density. The measured $K$ values of the composites were compared with those predicted by several theoretical models. Good microwave dielectric properties with values of $K$=3.6, $Qf$ = 7,788 GHz, and $TCF$ = -0.19 ppm/$^{\circ}C$ were obtained for the composites with 0.1 $V_f$ ceramics (mixed 0.025MTa and 0.075MTi).

• 대한생식의학회:학술대회논문집
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• 2003.12a
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• pp.108.2-109
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• 2003

• Korean Journal of Environmental Biology
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• v.26 no.4
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• pp.292-302
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• 2008

The purpose of this study was to analyze the trophic structures and the energy flows in the lower reaches of the Nakdong River using the Ecopath model (Walter et al., 1997). The sampling and analyses were carried out at 6 sampling sites of the lower reaches of the Nakdong River on May and November in 2007. Total of 9 groups detritus, macrophytes, phytoplankton, zooplankton, zoobenthos, Cyprinus carpio, Hemibarbus labeo, Micropterus salmoides and other fishes were considered to assess the trophic relationship, energy flows and interactions among them in the study. As a result, it was concluded that the lower reaches of the Nakdong River was consisted of producers (Detritus, Macrophytes, Phytoplankton), primary consumers (Zooplankton, Zoobenthos, Cyprinus carpio, Hemibarbus labeo, Other fishes) and secondary consumer (Micropterus salmoides). The total system throughput was estimated at 2.7 kg m$^{-2}$ year$^{-1}$ including a consumption of 52%, exports of 9.1%, respiratory flows of 18.0% and flows into detritus of 20.9%. MTI (mixed trophic impacts) analysis demonstrated that Pseudobagrus fulvidraco had positive impact on Cyprinus carpio, Carassius cuvieri and Carassius auratus. On the other hand, other fishes had negative impact on Cyprinus carpio, Carassius cuvieri and Carassius auratus. Also, all the functional groups except detritus had a negative impact on themselves.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.502-508
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• 1997

Rice bran dietary fiber extract, which was obtained after termamyl treatment of defatted rice bran contained $27.3{\sim}30.5%$ protein, $49.7{\sim}54.1%$ insoluble dietary fiber, and $1.9{\sim}2.7%$ soluble dietary fiber. Extrusion decreased the insoluble dietary fiber content but increased the soluble dietary fiber content, while roasting did not. Influence those content. Each mineral element content was depended upon heat processing method. Extrusion increased the water binding capacity and L value, while roasting reduced the water binding capacity and L value. Scanning electron microscopy showed damaged cell walls for extruded sample compared to roasted one which had fully collapsed cell walls. The increase of water absorption, developing time, and stability and the of MTI of wheat flour-dietary fiber extract composites with addition of dietary fiber extract were observed by Farinograph. Rice bran dietary fiber extract had an effect on the bread making resulting in increase of bread weight and color of crumb and crust, and decrease of bread volume and texture. As a result of sensory evaluation, appearance, texture, overall acceptability were significantly different from control but flavor and taste were not different significantly up to 6% level. Heat treated samples had differences in mean values, but not significant differences statistically.

• Development and Reproduction
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• v.6 no.2
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• pp.89-96
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• 2002

The present study was conducted to elucidate genes involved in the primordial-primary follicular transition. By using suppression subtractive hybridization, day1- and day5-subtracted cDNA libraries were obtained with the forward and reverse subtraction method, respectively. In toto, 357 clones were sequenced and analyzed by BLAST and RIKEN program. Sequences of 330 clones significantly matched database entries while 27 clones were novel. Forty-two and 47 genes with known functions were different between day1 and day5 ovaries. Four genes, GDF8, lats2, septin2, and wee1, from the day1 subtracted cDNA library, and 6 genes, HSP84, laminin2, MATER, MTi7, PTP, and wrn, from day5-subtracted cDNA library were chosen, and their differential expression was evaluated using RNAs from whole ovaries as well as captured primordial and primary follicles by laser captured microdissection. Results from the present study would provide insight for the future study on the mechanisms involved in primordial-primary follicle transition in the mouse in addition to the human ovary.

• IMMUNE NETWORK
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• v.6 no.4
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• pp.199-203
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• 2006

Background: Eckol purified from Ecklonia cava, a brown alga has been known to have cytoprotective effects on some cell lines against oxidants and ionizing radiation. However, there is no study about the effects of eckol on immune cells. Methods: Bone marrow (BM)-derived dendritic cells (DCs) were used to demonstrate the immunomodulatory effects of eckol on DCs, such as viability, the expression of surface markers, allogeneic stimulating capacity using MTI, flow cytometric, $^3H$-thymidine incorporation assay. Results: Eckol did protect DCs against cytokine withdrawal-induced apoptosis in a concentration dependent manner based on MTT assay. And also, it increased the expression of MHC class II and CD86 (B7.2) molecules, maturation markers, on the surface of viable DCs gated in FACS analysis. Furthermore, eckol-treated DCs stimulated the proliferation of allogeneic $CD4^+$ T lymphocytes compared to imDCs in $^3H$-thymidine incorporation assay. $CD4^+$ T lymphocytes activated with eckol-treated DCs produced the larger amount of IFN-${\gamma}$ and IL-4 than those cells with imDCs. Conclusion: Taken together, we demonstrate in this study that eckol, a pure compound of Ecklonia cava, may modulate the immune responses through the phenotypic and functional changes of DCs.