• Korean Journal of Microbiology
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• v.47 no.2
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• pp.110-116
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• 2011

In the previous study with the Saccharomyces cerevisiae S288c strains, no known function of the dual specificity kinase, ScKns1, was reported because its gene deletion did not show any noticeable phenotypic changes. Recent study with fission yeast, however, revealed the involvement of the LAMMER kinase in flocculation, filamentous growth, oxidative stress, and so on. Therefore we made Sckns1-deletion mutants with the ${\Sigma}1278b$-background, with which one can induce filamentous and adhesive growth in contrast to those of the S288c-background. The $Sckns1{\Delta}$ strains of both haploid and diploid showed defect in filamentous growth under conditions for inducing the filamentous growth such as nitrogen starvation and butanol treatment. Both kinds of the deletion mutants also showed decrease in adhesive growth on agar surface. Interestingly enough the defects of the $Sckns1{\Delta}$ strains were suppressed by the over-expression of each gene for the components of the MAPK signaling pathway such as STE11, STE12, and TEC1, respectively, but not by the upstream components, RAS2 and STE20, respectively. Although further investigations are required, these results indicate that the ScKns1 may act in place between the Ste20 and the Ste11 of the S. cerevisiae MAPK cascade.

• Archives of Plastic Surgery
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• v.37 no.2
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• pp.137-142
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• 2010

Purpose: Tumor ablation and traumatic intractable ulceration of the plantar surface of the foot results in skin and soft tissue defects of the weight-bearing sole. Simple skin grafting is not sufficient for reconstruction of the weight-bearing areas. Instead, the island medial plantar flap (instep flap) and distally-based island medial plantar flap was used for proper reconstruction of the weight bearing area. However, there are some disadvantages. In particular, an island medial plantar flap has a short pedicle limiting the mobility of the flap and the distally-based island medial plantar flap is based on a very small vessel. We investigated whether good results could be obtained using a reverse island medial plantar flap based on the lateral plantar vessel as a solution to the above limitations. Methods: Three patients with malignant melanoma were cared for in our tertiary hospital. The tumors involved the lateral forefoot, the postero-lateral heel, and the medial forefoot area. We designed and harvested the flap from the medial plantar area, dissected the lateral and medial plantar artery and vena comitans, and clamped and cut the vessel 1 cm proximal to the branch from the posterior tibial artery and vena comitans. The medial plantar nerve fascicles of these flaps anastomosed to the sural nerve, the 5th interdigital nerve, and the 1st interdigital nerve of each lesion. The donor sites were covered with skin grafting. Results: The mean age of the 3 subjects was 64.7 years (range, 57 - 70 years). Histologically, all cases were lentiginous malignant melanomas. The average size of the lesion was $5.3\;cm^2$. The average size of the flap was $33.1\;cm^2$. The flap color and circulation were intact during the early postoperative period. There was no evidence of flap necrosis, hematomas or infection. All patients had a normal gait after the surgery. Sensory return progressively improved. Conclusion: Use of an island medial plantar flap based on the lateral plantar vessel to the variable weight-bearing sole is a simple but useful procedure for the reconstruction of any difficult lesion of the weight-bearing sole.

• Journal of Chest Surgery
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• v.44 no.6
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• pp.406-412
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• 2011

Background: Development of thoracic aortic aneurysms and aortic dissections (TAAD) is attributed to unbearable wall tension superimposed on defective aortic wall integrity and impaired aortic repair mechanisms. Central to this repair mechanisms are well-balanced and adequately functional cellular components of the aortic wall, including endothelial cells, smooth muscle cells (SMCs), inflammatory cells, and adventitial fibroblasts. Adventitial fibroblasts naturally produce aortic extracellular matrix (ECM), and, when aortic wall is injured, they can be transformed into SMCs, which in turn are involved in aortic remodeling. We postulated the hypothesis that adventitial fibroblasts in patients with TAAD may have defects in ECM production and SMC transformation. Materials and Methods: Adventitial fibroblasts were procured from the adventitial layer of fresh aortic tissues of patients with TAAD (Group I) and of multi-organ donors (Group II), and 4-passage cell culture was performed prior to the experiment. To assess ECM production, cells were treated with TNF-${\alpha}$ (50 pM) and the expression of MMP-2/MMP-3 was analyzed using western blot technique. To assess SMC transformation capacity, cells were treated with TGF-${\beta}1$ and expression of SM ${\alpha}$-actin, SM-MHC, Ki-67 and SM calponin was evaluated using western blot technique. Fibroblasts were then treated with TGF-${\beta}1$ (10 pM) for up to 10 days with TGF-${\beta}1$ supplementation every 2 days, and the proportion of transformed SMC in the cell line was measured using immunofluorescence assay for fibroblast surface antigen every 2 days. Results: MMP-3 expression was significantly lower in group I than in group II. TGF-${\beta}1$-stimulated adventitial fibroblasts in group I expressed less SM ${\alpha}$-actin, SM-MHC, and Ki-67 than in group II. SM-calponin expression was not different between the two groups. Presence of fibroblast was observed on immunofluorescence assay after more than 6 days of TGF-${\beta}1$ treatment in group I, while most fibroblasts were transformed to SMC within 4 days in group II. Conclusion: ECM production and SMC transformation are compromised in adventitial fibroblasts from patients with TAAD. This result suggests that functional restoration of adventitial fibroblasts could well be a novel approach for the prevention and treatment of TAAD.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.330-335
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• 2017

The demand for electric motor fuel cells has surged in the automotive industry, leading to a recent increase in the demand for square aluminum cans used as fuel cell battery casings. The air vent located on the bottom of the rectangular battery casing prevents large explosions by intermittent pressure release prior to the accumulation of abnormally high pressures. Conventionally, the square cup battery casing is produced via six-step deep drawing, with the outer shape of the vent being manufactured by welding to the square battery casing. On the other hand, this study directly incorporated the air vent outlet into the bottom surface of the rectangular casing. The product of a coupled finite element analysis technique applying the thickness and contour generated from the square cup multi-step deep drawing formation analysis was used as the forging input shape. The results yielded increased prediction accuracy and the advanced prediction of defects, such as swelling and fracture. Based on the results of the initial analyses, two of the generated forging shapes were determined to be suitable, with the optimal forging shape being determined by molding analysis. The results presented here were validated by mold fabrication and a subsequent comparison of the actual and analytical results.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.3
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• pp.578-584
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• 2017

$SiO_2$ buffer layer (100 nm) has been deposited on PET substrate by electron beam evaporation. And then, IZTO (In-Zn-Sn-O) thin film has been deposited on $SiO_2$/PET substrate with different RF power of 30 to 60 W, working pressure, 1 to 7 mTorr, by RF magnetron sputtering. Structural, electrical and optical properties of IZTO thin film have been analyzed with various RF powers and working pressures. IZTO thin film deposited on the process condition of 50 W and 3 mTorr exhibited the best characteristics, where figure of merit was $4.53{\times}10^{-3}{\Omega}^{-1}$, resistivity, $4.42{\times}10^{-4}{\Omega}-cm$, sheet resistance, $27.63{\Omega}/sq.$, average transmittance (400-800 nm), 81.24%. As a result of AFM, all the IZTO thin film has no defects such as pinhole and crack, and RMS surface roughness was 1.147 nm. Due to these characteristics, IZTO thin film deposited on $SiO_2$/PET structure was found to be a very compatible material that can be applied to the next generation flexible display device.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.6
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• pp.491-497
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• 2001

Polymethylmethacrylate(PMMA) is currently commonly used material for the reconstruction of bone defects and fixation of joint prosthetics following congenital and acquired causes. Although PMMA has widespread use, it does not possess the ideal mechanical characteristics with osteoconductivity and osteoinductivity required. In order to overcome these problem, addition of bovine bone drived defatting demineralized bone(BDB) powders to a PMMA bone cement was done for improvement of physical property and bone forming characteristics of composite. In order to investigate the influence of BDB reinforcement on the PMMA, we measured physical property of compressive, tensile, flexural strength, and scanning electron microscopic examinations. The results were obtained as follows: 1. The PMMA forms a solid cellular matrix with open cells about $100{\mu}m$ in variable size and incorporating BDB. BDB aggregates inside the cells form a porous network that is accessible from the outer surface. 2. The physical properties were compressive strength of mean $22.74{\pm}1.69MPa$, tensile strength of mean $22.74{\pm}1.69MPa$, flexural strength of mean $77.53{\pm}6.93MPa$. Scanning electron microscopic examinations were revealed that there was DBD particles form a highly porous agglomerates. BDB can be added PMMA in the form of dried powders, the composites are applicable as bone substitutes. BDB and PMMA mixture is shown to produce a class of composites that due to their microstructure and improved mechanical properties may be suitable for application as bone subsitutes. The mechanical and material properties of the BDB-PMMA bone substitute composites are competitive with those properties of a porous ceramic matrix of other hydroxyapatite and with those of natural bones.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.19 no.2
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• pp.39-46
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• 2013

Background: The purpose of this study was to realize the relations between gluteus medius, tensor fascia lata of pelvic muscles and functional leg length in women's university students. This study is examined the change of electromyographic activation on gluteus medius and tensor fascia lata according to the leg length discrepancy. Methods: All of the female of freshman and sophomore in 'D'college were gathered and separated fourteen of healthy women in two groups by functional leg length discrepancy. and The subjects divided into two groups that the difference with less than 2cm or more would have structural defects by tapeline. The electromyographic activation on the gluteus medius and tensor fascia lata muscles were recorded by surface electrodes at maximal voluntary isometric contraction (MVIC) during lunge posture. The collected datas were analyzed using Independent t-test with SPSS win19.0. Results: In intergroup comparison of electromyographic activation levels for gluteus medius and tensor fascia lata in short or long leg, the influence of electromyographic activation on tensor fascia lata is shown to be more statically higher than gluteus medius according to functional leg length discrepancy in coeds. Even though both muscles are shown to be statistically higher in comparison of electoromyographic activation levels for tensor fascia lata and gluteus medius between short leg and long leg in Group I, Differences of electoromyographic activation levels for tensor fascia lata is shown to be statistically higher than gluteus medius. Conclusion: Through this study, we realized that tensor fascia lata than the long leg, and also, tensor fascia lata is significantly effective for functional leg length discrepancy than gluteus medius. It leads to pelvic lateral instability. This means that cause tensor fascia lata to have a leg length discrepancy.

• Journal of Life Science
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• v.30 no.6
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• pp.563-569
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• 2020

Oncoplastic surgery (OPS) combines oncologically safe tumor resection with aesthetically satisfying reconstruction of defects using established plastic surgery techniques. OPS is characterized by initial excision as extensive as is beneficial for oncological safety, and, once sufficient resection is complete, displacement or replacement techniques are selected based on remnant volume. The size of the lesion and the individual patient are important factors when considering the appropriate approach, and when pre-operative imaging, including MRI, is used to determine the technique, the complete removal of cancer cells by permanent pathology is essential. A frozen section is used during the operation to reduce the reoperation rate, but it is difficult to cover the entire margin surface theoretically and even harder in practice. A recent report about adequate margins has empowered OPS in its oncological safety. Considering the patients to whom each modality could be applied, basic breast volume is an important factor, and this is influenced by ethnic differences. In Europe or the US, for example, the average breast size is 36D (600 ㎤) and reduction mammoplasty is predominantly used. However, the average size of patients in our institution is 33A (300 ㎤), and so quite different approaches are selected in most cases. New techniques involving radiofrequency and fluorescence have been proposed as safe and easily accessible ways of reducing complications.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.415-417
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• 2002

Images of microcalcification specks showed large variation in conventional radiographs of phantoms which are approved for mammography image quality standard by the American College of Radiology (ACR). This kind of variation is not appropriate for image quality standards because the number of specks are visually counted in images and that number is important in image quality evaluation. Our study using synchrotron radiation (SR) imaging revealed the overlapping of micro-sized air bubble(s) to some specks, and also the structural deformation or crackings. Eight phantoms approved by ACR from two different makers and an air-bubble phantom were examined. SR imaging was performed at a synchrotron radiation facility, SPring-8, in Japan. The image-detector was a fluorescent-screen optical-lens coupling system using a CCD camera with a spatial resolution of 6 $\square$m. Objects when imaged with longer sample-to-detector distance show edge enhancement due to a difference in refraction indices, that is refraction enhancement. Refraction-enhanced SR images revealed that some of specks carried foreign objects, which were proven to be air. In phantoms provided by one maker, attaching/overlapping airs were observed for 62 out of 150 specks (41%) , with a higher incidence for the smallest specks. A speck becomes hardly visible in a conventional radiograph when air(s) overlaps the majority part of a speck, though depending on the size of the air-inclusion and on its configuration. Those airs might have been adsorbed on a speck surface before being embedded and then introduced into the matrix together with specks. Our study using SR imaging has clearly shown the nature of defects in some mammography phantoms which seriously degrade the quality as an image standard.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.7
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• pp.8-16
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• 2010

In this paper, we investigated the effects of $O_2$ fraction on the properties of Al-doped ZnO (AZO) thin films prepared by radio frequency (RF) magnetron sputtering. Hall, photoluminescence (PL), and X-ray photoelectron spectroscopy (XPS) measurements revealed that the p-type conductivity was exhibited for AZO films with an $O_2$ fraction of 0.9 while the n-type conductivity was observed for films with $O_2$ fractions in range of 0 - 0.6. PL and XPS also showed that the acceptor-like defects, such as zinc vacancies and oxygen interstitials, increased in films prepared by an $O_2$ fraction of 0.9, resulting in the p-type conductivity in the films. Hall results indicated that AZO films prepared by $O_2$ fractions in range of 0 - 0.6 can be used for electrode layers in the applications of transparent thin film transistor. We concluded from the X-ray diffraction analysis that worse crystallinity with a smaller grain size as well as higher tensile stress was observed in the films prepared by a higher $O_2$ fraction, which is related to incorporation of more oxygen atoms into the films during deposition. The study of atomic force microscope suggested that the smoother surface morphology was observed in films prepared by using $O_2$ fraction, which causes the higher resistivity in those films, as evidenced by Hall measurements.