• Journal of Microbiology and Biotechnology
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• v.25 no.10
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• pp.1768-1771
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• 2015

Human Fen1 protein (hFen1) plays an important role in Okazaki fragment processing by cleaving the flap structure at the junction between single-stranded (ss) DNA and doublestranded (ds) DNA, an intermediate formed during Okazaki fragment processing, resulting in ligatable nicked dsDNA. It was reported that hChlR1, a member of the cohesion establishment factor family, stimulates hFen1 nuclease activity regardless of its ATPase activity. In this study, we found that cohesion establishment factors cooperatively stimulate endonuclease activity of hFen1 in in vivo mimic condition, including replication protein-A-coated DNA and high salt. Our findings are helpful to explain how a DNA replication machinery larger than the cohesion complex goes through the cohesin ring structure on DNA during S phase in the cell cycle.

• Reproductive and Developmental Biology
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• v.40 no.2
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• pp.23-26
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• 2016

Transcription factor called activating enhancer binding protein 2C (AP2-gamma) is found in a variety of species and expressed from oocyte stage onwards, particularly restricted to the trophectoderm. Recent studies demonstrated that ablation of Tfap2c led to failure of tight junction biogenesis, particularly the knock-down embryos of Tfap2c did not form cavity from morula to blastocyst in mouse and pig. We speculated that the Tfa2pc may also be involved in desmosome biogenesis because blastocoel formation is coincident with the establishment of desmosome. To determine this, we depleted Tfap2c injecting siRNA into one-cell zygote and analysed the expression levels of genes that are required for desmosome complex such as PkP2, Pkp3, Dsc2, and Dsg2. We found only Pkp3 was up-regulated in the knockdowned morula embryos. Interestingly, upstream region of Pkp3 had putative Tfap2c binding sites. In conclusion, our results suggest that Tfap2c is not a crucial factor but somehow it might be involved in desmosome biogenesis directly or indirectly via Pkp3.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.3
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• pp.403-413
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• 2017

Dual-point aerodynamic design optimization is conducted for DLR-F6 wing-body-nacelle-pylon configuration adopting an efficient surface mesh movement method for complex junction geometries. A three-dimensional unstructured Euler solver and its discrete adjoint code are utilized for flow and sensitivity analysis, respectively. Considered design conditions are a low-lift condition and a cruise condition in a transonic regime. Design objective is to minimize drag and reduce shock strength at both flow conditions. Shape deformation is made by variation of the section shapes of inboard wing and pylon, nacelle vertical location and nacelle pitch angle. Hicks-Henne shape functions are employed for deformation of the section shapes of wing and pylon. By the design optimization, drag coefficients were remarkably reduced at both design conditions retaining specified lift coefficient and satisfying other constraints. Two-point design results show mixed features of the one-point design results at low-lift condition and cruise conditions.

• Development and Reproduction
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• v.5 no.2
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• pp.115-122
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• 2001

Production of a mature oocyte is a complex process that requires the close association between oocyte and follicular cells. The present study was conducted to investigate the difference between oocytes with and without close junctional communication with cumulus cells and the involvement of two connexins(CXs) in the interactions. Follicles at different sizes(small: 200～400 ㎛; large:>450 ㎛) were mechanically isolated from PMSG-primed mouse ovaries, and punctured to get cumulus-oocyte complex(COC). Oocytes were released themselves(denuded), with partially attached(partial), or with tightly attached(intact) cumulus cells. Maturation and fertilization capacity of the COCs were measured. Expression of CX 37 and CX 43 was examined by RT-PCR and in situ hybridization. The ratio between intact COC and denude/partial oocytes was 30％(SI) and 70％(SPD) in small follicles, while 55％(LI) and 45％(LPD) in large follicles, respectively. Maturation and fertilization rates of the released oocytes were similar among SI, LPD, LI groups, but those were significantly lower in SPD oocytes. In oocytes, CX 37 was the major CX and CX 43 was not expressed, whereas in the cumulus cells, CX 43 was the major, and CX 37 was the next. Results of the present study suggest that 1) immature oocytes from small follicles with intact cell-to-cell communication with cumulus have the similar quality to that of the oocytes from larger follicles, 2) gap junction between oocyte and cumulus cells may be the heterotypic channel, and 3) we could not explain the difference in the cell-to-cell communication between intact and partial/denuded COCs through the expression of the two CXs.

• Korean Journal of Materials Research
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• v.3 no.5
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• pp.553-561
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• 1993

In this study, thr effect of $Bi_2O_3$ and BN addition as grain boundary modifiers on sintering and electrical properties of semiconducting PTCR(Positive Temperature Coefficient of Resistivity) mate rial were analyzed using TMA, XRD and Complex Impedance Spectroscopy method. Bismut.h Ox~de and Boron Nitride were added to Y-doped $BaTiO_3$ respectively. Bismuth sesquioxide up to O.lmol%solubil~ ty limit of $Bi_2O_3$ in Y--$BaTiO_3$ ceramics-retarded densification and grain growth, and further addition mitigated these retardation effects. The resistivity at room temperature increased with increasing amount of $Bi_2O_3$ and thus decreased the PTCR effect, probably due to the $Bi_2O_3$ segregation on the grain boundaries. From the complex ~mpedance pattern, it is known that the grain boundary resisitivity is dominant on the whole resistivity of sample. In the result of applying the defect chemistry, $Bi^{3+} \;and \; Bi^[5+}$ are substituted for Ua and Ti site, respectively. Boron nitride decomposed and formed liquid phase among the $BaTiO_3$ grains. The decomposed com~ ponents made the second phase and existed the tr~ple juntion from the result of EPMA. From the complex impendencc pattern, the gram and grain boundary resistivity were small. The grain size increased with increasing BN contents, and decreased grain boundary resistivity enhanced the PTCR effect.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.3
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• pp.239-249
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• 2001

The purpose of this study is to evaluate the relationship of the factors which could be influenced by orthognathic surgery especillay SSRO. We measured the amounts of the maximum opening, lateral movements, maximum velocity and pattern of mandibular path during the opening and closing of mandible at the following times ; preoperative, 1 month after operation, 6 months after operation respectively using MKG. And the results were compared according to the categorized subgroups. Following results were obtained : 1. The change of the amounts of mandibular lateral movement and maximum opening velocity were statistically different between male and female (p<0.05), but the others were not. 2. According to the method of operation, there was no difference in the change of the mandibular movements between the group of SSRO and SSRO plus LeFort I osteotomy (p>0.05). 3. According to the amounts of mandibular movement, the recovery of left lateral movement of the group of $6{\sim}10mm$ was better than the other groups (p<0.05). 4. In the frontal pattern of the opening and closing of the mandible, the complex deflected type (F5), simple deflected type (F4), complex deviated type (F3), simple deviated type (F2), straight type (F1) were obtained in order at the time of preoperative, simple deflected type, simple deviated type, complex deviated type, straight type, complex deflected type in order at the time of 1 month after surgery, and the result at the time of 6 months after surgery was the same with that of the time of preoperative. In the sagittal pattern, non-coincident type (S2) was predominant at the time of preoperative, and coincident type (S1) was predominant at the time of 1 month after surgery. After 6 months, the result was also the same with that of the preoperative in sagittal pattern. 5. There was not a statistical difference in the change of the mandibular movement between group of presence of the preoperative TMJ symptoms and non-presence group (p>0.05). 6. There was not a statistical difference in the change of the mandibular movement between repositioning device applied group and non-applied group (p>0.05). 7. Sixty three percents of the patients who had preoperative TMJ symptoms were improved after surgery and preoperative TMJ symptoms were more improved after operation in the repositioning device non-applied group statistically (p<0.05).

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.61.1-61.1
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• 2010

$CuIn_{1-x}-GaxSe_2$ based materials with direct bandgap and high absorption coefficient are promising materials for high efficiency hetero-junction solar cells. CIGS champion cell efficiency(19.9%, AM1.5G) is very close to polycrystalline silicon(20.3%, AM1.5G). A reduction in the price of CIGS module is required for competing with well matured silicon technology. Price reduction can be achieved by decreasing the manufacturing cost and by increasing module efficiency. Manufacturing cost is mostly dominated by capital cost. Device properties of CIGS are strongly dependent on doping, defect chemistry and structure which in turn are dependent on growth conditions. The complex chemistry of CIGS is not fully understood to optimize and scale processes. Control of the absorber grain size, structural quality, texture, composition profile in the growth direction is important to achieving reliable device performance. In the present work, CIS nanoparticles were prepared by a simple wet chemical synthesis method and their structural and optical properties were investigated. XRD patterns of as-grown nanopowders indicate CIS(Cubic), $CuSe_2$(orthorhombic) and excess selenium. Further, as-grown and annealed nanopowders were characterized by HRTEM and ICP-OES. Grain growth of the nanopowders was followed as a function of temperature using HT-XRD with overpressure of selenium. It was found that significant grain growth occurred between $300-400^{\circ}C$ accompanied by formation of ${\beta}-Cu_{2-x}Se$ at high temperature($500^{\circ}C$) consistent with Cu-Se phase diagram. The result suggests that grain growth follows VLS mechanism which would be very useful for low temperature, high quality and economic processing of CIGS based solar cells.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.2
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• pp.220-227
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• 2017

Pre-eruptive intracoronal resorption (PEIR) is a rare radiolucent lesion often located within the dentin and adjacent to the dentin-enamel junction, underneath the occlusal aspect of the crowns of unerupted teeth. The treatment approaches for these lesions involved with unerupted teeth have been known as to be relatively simple; depending on the extent of resorption, follow-up or restoration can be performed after surgical exposure. However, once the tooth is exposed to the oral cavity after eruption, it becomes highly vulnerable to the development of carious lesions. Thus, immediate intervention is required in such cases; failure to address it may result in the need for more complex treatments including endodontic therapy. The aim of this case report was to describe the characteristics of PEIR and the clinical management of the impacted immature permanent teeth diagnosed with PEIR.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.1
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• pp.51-56
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• 2007

Flow characteristics in a liquid fuel ramjet combustor were investigated using the PIV method. The combustor has two rectangular inlets that form a $90^{\circ}$ angle each other. Three cases of test combustors are made in which those inlet angles are $30^{\circ},\;45^{\circ}\;and\;60^{\circ}$. The experiments were performed in a water tunnel test with the same Reynolds number as Mach 0.3 at the inlet. PIV software was developed to measure the characteristics of the flow field in the combustor. A large and complex recirculating flow was measured in the dome area with 4 different dome size. Experimental results shows that 1/3 dome size of combustor diameter is suitable and smaller inlet angle provide large recirculation flow at the dome of combustor as a frame holder in this experimental ranges but need to consider secondary recirculation flow in a junction region to optimize the configuration of ramjet combustor.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.23 no.2
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• pp.111-118
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• 2012

Botulinum toxin is a potent neurotoxin that is produced by the bacterium Clostridium botulinum. The agent causes muscle paralysis by preventing the release of acetylcholine at the neuromuscular junction of striated muscle. Botulinum toxin A (Botox, AllerganInc., Irvine, California) is the most potent of seven distinct toxin subtypes that are produced by the bacterium. The toxin was initially used clinically in the treatment of strabismus caused by hypertonicity of the extraocular muscles and was sub-sequently described in the treatment of multiple disorders of muscular spasticity and dystonia. In treating patients with Botox for blepharospasm, Carruthers and Carruthers [5] noticed an improvement in glabellar rhytids. This ultimately led to the introduction and development of Botox as a mainstay in the treatment of hyperfunctional facial lines in the upper face. Since its approval by the U.S. Food and Drug Administration for the treatment of facial rhytids (2002), botulinum toxin A has expanded into wide-spread clinical use. Forehead, glabellar, and periocular rhytids are the most frequently treated facial regions. Indications for alternative uses for Botox in facial plastic and reconstructive surgery are expanding. These include a variety of well-established procedures that use Botox as an adjunctive agent to enhance results. In addition, Botox injection is finding increased usefulness as an independent modality for facial rejuvenation and rehabilitation. The agent is used beyond its role in facial rhytids as an effective agent in the management of dynamic disorders of the face and neck. Botox injection allows the physician to precisely manipulate the balance between complex and conflicting muscular interactions, thus resetting their equilibrium state and exerting a clinical effect. This article will address some of the new and unique indications on Botox injection in the face (the lower face and neck, combination with fillers). Important points in terms of its clinical relevance will be stressed, such as an understanding of functional facial anatomy, the importance of precise injections, and correct dosing all are critical to obtaining natural outcomes.