• Environmental Mutagens and Carcinogens
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• v.26 no.3
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• pp.69-76
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• 2006

2,3,7,8-Tetrachlorodibenzo-$\rho$-dioxin(TCDD) is a ubiquitous, persistent environmental contaminant and the most powerful carcinogen categorized by IARC. Although the mechanism of carcinogenesis by TCDD is poorly understood, several studies have shown that the skin is one of target organs far TCDD. In this study, we investigated the neoplastic transformation of human keratinocyte-derived cell line, HaCaT, by chemical transformation method using N-methyl-N'-nitro-N-nitrorsoguanidine(MNNG) and TCDD. We found that subsequent exposure to TCDD for 3 weeks after initial exposure to MNNG markedly induced transformed cells. It was suggested that TCDD can act as a potent promoter in HaCaT cells. Furthermore, these transformed cells showed morphological alternations in soft agar and increased telomerase activity. Therefore, the TCDD treatment of HaCaT cells by initiated with MNNG could promote neoplastic transformation without stimulation by exogenous growth factors. As a result, TCDD had a strong potency as a promoter in nontumorigenic immortalized human epidermal keratinocytes.

• Journal of Korean Association for Spatial Structures
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• v.7 no.4
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• pp.73-78
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• 2007

The surrounding ground was much transformed by the lateral movement on the soft ground, and consequently the stake basis was damaged. In this case the installed stake is ratted the passive stake, and is actively being researched. When the unevenly distributed load was applied on the stake, and thus the lateral ground pressure was operated, and then the lateral movement was occurred, and consequently the structure is influenced. However, prediction and mechanism for the relationship of piles and abutment deformation is not sufficient. In this paper, coupled three-dimensional finite element analysis, which can be described solid, plate and frame elements at the same time, is developed by the authors. The lateral movement of bridge abutment for the aspect ratio of steel piles on soft clay is clarified by using developed numerical analysis.

• Journal of Communications and Networks
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• v.2 no.1
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• pp.76-84
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• 2000

Communication systems, including cell-based mobile communication systems, multiple satellite communication systems of multi-beam satellite systems, require reliable handoff methods between cell-to-cell, satellite-to-satellite of beam-to-team, respectively. Recent measurement of a CDMA cellular system indicates that the system is in handoff at about 35% to 70% of an average call period. Therefore, system reliability during handoff is one of the major system performance parameters and eventually becomes a factor in the overall system capacity. This paper presents novel and improved techniques for handoff in cellular communications, multi-beam and multi-satellite systems that require handoff during a session. this new handoff system combines the soft handoff mechanism currently implemented in the IS-95 CDMA with code and packet diversity combining techniques and an iterative decoding algorithm (Turbo Coding). the Turbo code introduced by Berrou et all. has been demonstrated its remarkable performance achieving the near Shannon channel capacity [1]. Recently. Turbo codes have been adapted as the coding scheme for the data transmission of the third generation international cellular communication standards : UTRA and CDMA 2000. Our proposed encoder and decoder schemes modified from the original Turbo code is suitable for the code and packet diversity combining techniques. this proposed system provides not only an unprecedented coding gain from the Turbo code and it iterative decoding, but also gain induced by the code and packet diversity combining technique which is similar to the hybrid Type II ARQ. We demonstrate performance improvements in AWGN channel and Rayleigh fading channel with perfect channel state information (CSI) through simulations for at low signal to noise ratio and analysis using exact upper bounding techniques for medium to high signal to noise ratio.

• Archives of Plastic Surgery
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• v.40 no.6
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• pp.666-675
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• 2013

Background Stem cells are a unique cell population characterized by self-renewal and cellular differentiation capabilities. These characteristics, among other traits, make them an attractive option for regenerative treatments of tissues defects and for aesthetic procedures in plastic surgery. As research regarding the isolation, culture and behavior of stem cells has progressed, stem cells, particularly adult stem cells, have shown promising results in both translational and clinical applications. Methods The purpose of this review is to evaluate the applications of stem cells in the plastic surgery literature, with particular focus on the advances and limitations of current stem cell therapies. Different key areas amenable to stem cell therapy are addressed in the literature review; these include regeneration of soft tissue, bone, cartilage, and peripheral nerves, as well as wound healing and skin aging. Results The reviewed studies demonstrate promising results, with favorable outcomes and minimal complications in the cited cases. In particular, adipose tissue derived stem cell (ADSC) transplants appear to provide effective treatment options for bony and soft tissue defects, and non-healing wounds. ADSCs have also been shown to be useful in aesthetic surgery. Conclusions Further studies involving both the basic and clinical science aspects of stem cell therapies are warranted. In particular, the mechanism of action of stem cells, their interactions with the surrounding microenvironment and their long-term fate require further elucidation. Larger randomized trials are also necessary to demonstrate the continued safety of transplanted stem cells as well as the efficacy of cellular therapies in comparison to the current standards of care.

• Journal of the Korean Geotechnical Society
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• v.27 no.3
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• pp.55-61
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• 2011

Generally, the Box-Culvert in levee is destroyed by various reasons. Especially when Box-Culvert is installed over the pile foundation in soft ground, the failure occurrs for 1) the weakness of compaction in Box-Culvert side by the differential settlement between outer ground and inner soil prism, 2) hydraulic fracturing and disturbance of Box-Culvert side soil by the repeated acting of seepage pressure at flood time. Also the side of Box-Culvert is difficult to compact and the shear resistance is reduced by more than 1/3 for the reduction of friction caused by the difference of material property. In this study, a series of model tests are conducted for the analysis of the development mechanism of outer ground and inner soil prism by the differential settlement using the pile foundation in soft ground, and cavity suppressed technique is suggested by the analysis of base plate enlargement effect.

• Journal of Advanced Navigation Technology
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• v.15 no.4
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• pp.655-663
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• 2011

Recently, with improvement of internet service technology, web service has been affecting the environment for computing user. Not only current events, economics, game, entertainment, but also personal financial system is processed by web pages through internet. When data transmission is implemented on the internet, webpage acquire text form code and transform them to DOM information, and then shows processed display to user by web browser. However, those information are not only easily accessed by diversified route, but also easily deformed by intentional purpose. Furthermore, it is also possible to acquire logon information of users and certification information by detouring security mechanism. Therefore, this dissertation propose the method to verify integrity of web contents by using BHO which is one of the Add-On program based on MS Internet Explorer platform which is one of major web browser program designed by MicroSoft to detect any action of webpage deformation.

• Archives of Plastic Surgery
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• v.40 no.3
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• pp.226-231
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• 2013

Background The reconstruction of volar surface defects is difficult because of the special histologic nature of the tissue involved. The plantar surface is the most homologous in shape and function and could be considered the most ideal of reconstructive options in select cases of volar surface defects. In this paper, we evaluate a single institutional case series of volar tissue defects managed with second toe plantar free flaps. Methods A single-institution retrospective review was performed on 12 cases of reconstruction using a second toe plantar free flap. The mean age was 33 years (range, 9 to 54 years) with a male-to-female ratio of 5-to-1. The predominant mechanism was crush injury (8 cases) followed by amputations (3 cases) and a single case of burn injury. Half of the indications (6 cases) were for soft-tissue defects with the other half for scar contracture. Results All of the flaps survived through the follow-up period. Sensory recovery was related to the time interval between injury and reconstruction-with delayed operations portending worse outcomes. There were no postoperative complications in this series. Conclusions Flexion contracture is the key functional deficit of volar tissue defects. The second toe plantar free flap is the singular flap whose histology most closely matches those of the original volar tissue. In our experience, this flap is the superior reconstructive option within the specific indications dictated by the defect size and location.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.9A
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• pp.1013-1021
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• 2004

In the WCDMA mobile multimedia communication system, the adaptive array antenna IS adopted to improve the performance of the system by reducing inter-user interference using antenna beam control. Usually, the interference resulted from the higher data rate users is much more significant to the lower data rate users than the other way around, so the overall performance can be enhanced by reducing the interference from higher data rate users. In order to maximize the efficiency of adaptive antenna operation, an optimal call admission control, especially during handoff, adaptive to the data rates is a critical problem. In this paper, We propose a call admission control algorithm based on the Soft QoS concept for the efficient processing of the handoff of higher data rate calls, and an adaptive handoff control mechanism according to the data rates. The proposed algorithm has been evaluated by computer simulation that it accommodates high data rate users among many lower data rate users much better, and the average call blocking probability for lower rate users becomes much lower than the conventional call admission control algorithm.

• Archives of Reconstructive Microsurgery
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• v.13 no.2
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• pp.136-143
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• 2004

Purpose : We analyse retrospectively the clinical result of consecutive free flap and osteocutaneous flap transfer in the chronic osteomyelitis, nonunion combined with infection and soft tissue defect with infection. Materials and Methods : From December 1989 to Jun 2003, free flap and osteocutaneous flap transfer was performed in 225 patients with osteomyelitis or infected non-union. 44 cases of these patients had revealed antibitotics resistant organism in wound culture, and these 44 cases were investigated in the mechanism of the injury, recurrence of infection, radiographic union, follow-up clincal results, and postoperative complications. Results : Among the 44 cases, consecutive procedures of osteocutaneous flap transfers(26 cases) and free flaps(18 cases) were performed. Causative organisms were MRSA(20 cases), Pseudomonas aeruginosa(18 cases), acinetobacter(2 cases), and so forth. Initial bony union was obtained in the average 6.3 months. Recurrence of infection in free flap and osteocutaneous free flap were occurred in 3 and 4 cases respectively. Eventually, all the cases attained successful subsidence of the inflammation. Conclusion : Free flap and osteocutaneousflap transfer have provided the greatest improvement of surgical results in infected non-union, chronic osteomyelitis and soft tissue defect with infection. Further clincal studies maybe required to minimize failure rate.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1972.03a
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• pp.3.2-3
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• 1972

Recently the adenosinetriphosphates have massive highlight due to their high energy source for treat and maintained all the cell mechanism in the individual. When the A. T.P. release the terminal phosphate, produces about 8,000 calories instead of the 3,000 calories from common chemical bonds. The high energy-P bond enables the cell to accumulate a great amount of energy in a very small space and the keep it ready to be used as soon as it is needed. The presence of A.T.P. explains why some important cellular functions such as nerve conduction can go on for some time even with complete inhibition of respiration. In recent years the A.T.P. were used in many clinical field with good effects. In this report was used A.T.P. 20mg＋Vit $B_1$ 50mg＋20% Dextrose 20㏄ through intravenousely for E.N.T. neurologic patient, such as neurogenic hearing impairment, tinnitus, dizziness, soft palate paralysis. By the injection 40% of neurogenic hearing impairment patients were improved and 62% tinnitus patients were improved and all the soft palate paralysis patient were completely recovered.