• Korean Journal of Head & Neck Oncology
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• v.19 no.1
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• pp.25-33
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• 2003

Background and Objectives: The Herpes Simplex type 2 Defective Infectious Single Cycle virus (DISC virus) is attenuated virus originally produced as viral vaccines but are also efficient gene transfer vehicle. The main goals of this study were to examine the efficiencies of the gene transfer using DISC vectors for various head and neck squamous cell carcinoma cell lines and to evaluate the efficacy of vaccination with DISC virus carrying a immunomodulatory genes (GM-CSF) as cancer therapy in a organotopic oral cavity squamous cell cancer model. Materials and Methods : We determinated the gene transfer efficiency of DISC virus by x-gal stain method and proved gene and protein expression of DISC-GMCSF transfected SCCVII cells by RT-PCR and ELISA method. Also we evaluated the ex vivo vaccination effects of SCCVII/GMCSF (DISC-GMCSF transfected SCCVII vaccine) vaccine on preventing the recurrence of micro-residual tumor. After the vaccination of SCCVII/GMCSF, specific cytotoxic T-cell responses was evaluated by CTL assay. Results: At an MOI of 10 DISC virus showed 64-88% of transfection rates in various head and neck squamous cancer cell lines. SCCVII cells transduced by DISC virus vector (MOI=10) carrying the GM-CSF gene, produced 4.5 nanogram quantities of GM-CSF per $10^6$ cells. In vivo vaccination using tumor cells transduced ex vivo with DISC-GMCSF resulted in better protection rate against subsequent tumor recurrence in organotopic oral cavity cancer model. Although tumor free survival rate was not statistically significantly increased in vaccination group (p=0.078), tumor specific cytotocic T-cell responses were significantly increased in SCCVII/GMCSF vaccination group. Conclusion: These data demonstrate that; 1) The DISC virus vector is capable of efficient gene transfer to various head and neck squamous cancer cell lines, 2) GM-CSF secreting genetically modified tumor vaccine (SCCVII/GMCSF) efficiently protected against tumor recurrence in organotopic micro-residual oral cavity cancer model and produced tumor specific cytotoxic T-cell response. DISC virus-mediated, cytokine gene transfer may prove to be useful as a clinical therapy for head and neck cancers.

• Journal of the Korean Society of Safety
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• v.23 no.3
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• pp.25-29
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• 2008

In automotive disc brake system, friction heat is not uniformly distributed due to various reasons such as thermal expansion and imperfections in geometry. It is well known that thermoelastic distortion due to fictional heating affects the contact pressure distribution and can lead to thermoelastic instability, where the contact load is concentrated in one or more small regions on the brake disc surface. These regions then take very high temperatures and passage of hot spots moving under the brake pads can cause low frequency vibration called brake judder. This paper presents the FEM(finite element method) result for the temperature distribution of ventilated disc brake. A steady state two-dimensional model of disc brake system predicts the surface temperatures during a multi-stop driving schedule.

• The KSFM Journal of Fluid Machinery
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• v.10 no.1 s.40
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• pp.41-48
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• 2007

The effect of the upstream flow conditions on the disc stability of the swing check valves was investigated at various upstream flow disturbance sources and distances from the tested check valves. The experimental loop was designed and installed to measure the disc positions, disc back stop load, and differential pressure at flow velocities lot 3 inch and 6 inch swing check valves. The selected disturbance sources are elbow and globe valve. The effect of the disc fluctuation is different depending on the type of disturbance and the distance between the disturbance and the check valve. Disturbances generated by elbow and globe valve located upstream from check valve create greater and more violent disc motion than uniform flow.

• Journal of Korean Neurosurgical Society
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• v.38 no.4
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• pp.320-322
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• 2005

A 45-year-old man presented with lower back pain and pain in the right leg of 3years duration. A plain radiographic examination revealed grade I isthmic spondylolisthesis, with instability at L4-5. Computed tomography and magnetic resonance imaging demonstrated bilateral foraminal stenosis, with soft foraminal disc herniation on the right side at the L4-5 level. He underwent anterior lumbar interbody fusion[ALIF] with percutaneous posterior fixation[PF] at the L4-5 level. Without removing the posterior bony structures, removal of foraminal disc herniation and reduction of spondylolisthesis were successfully performed using ALIF with percutaneous PF. When there is no hard disc herniation or lateral recess stenosis, ALIF with percutaneous PF can be one of the treatment options for isthmic spondylolisthesis, even in the presence of foraminal disc herniation, as in our case.

• Journal of Korean Neurosurgical Society
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• v.47 no.3
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• pp.217-220
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• 2010

A 73-year-old male presented with a rare dorsally sequestrated lumbar disc herniation manifesting as severe radiating pain in both leg, progressively worsening weakness in both lower extremities, and urinary incontinence, suggesting cauda equina syndrome. Magnetic resonance imaging suggested the sequestrated disc fragment located in the extradural space at the L4-L5 level had surrounded and compressed the dural sac from the lateral to dorsal sides. A bilateral decompressive laminectomy was performed under an operating microscope. A large extruded disc was found to have migrated from the ventral aspect, around the thecal sac, and into the dorsal aspect, which compressed the sac to the right. After removal of the disc fragment, his sciatica was relieved and the patient felt strength of lower extremity improved.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1436-1440
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• 1996

The wear mechanism of material is an important mechanic property to select a material's life and a optimum work condition. Although there are many researches about a wear mechanism of material, the pin-on-disc type tribotester is widely known to us. It is difficult to add a variable and heavy load in the existing pin-on-disc type tribotester to estimate this wear mechanism. And due to a rotation of a disc, it is impossible to add a constant force. But we can solve this problem by using a hydraulic servo system. Therefore, in order to investigate a wear mechanism of materials, it is necessary to design a hydraulic pin-on-disc type tribotester and construct a controller against a variable disturbance.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.5
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• pp.16-23
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• 2004

The wear behavior as the hardness of the sliding elements on the dry wear has been investigated using a disc on disc configuration. The materials of the specimens are used as ten kinds along their hardness. In this study, both upper and lower specimens have been used the same materials. Using experimental data, we figured the relationship between wear coefficient and friction coefficient, and the relationship between wear coefficient and friction temperature. Also we combined friction temperature and friction coefficient instead of wear coefficient. We substituted this into wear equation of Archard. The result had been derived a newly wear equation in disc on disc wear system.

• Proceedings of the Korean Reliability Society Conference
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• 2011.06a
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• pp.99-106
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• 2011

In this study, the analysis technique, which can estimate the temperature rise and thermal deformation of the ventilated disc considering the vehicle information, braking condition and properties of the disc and pad, is developed. The analytical process of the braking power generation during braking is mathematically derived. The thermal energy, which is applied to the surface of a disc as heat flux, is calculated. Then, the temperature rise and thermal deformation of a disc are estimated using FE software, SAMCEF. Shape of the cross section of the disc is optimized according to the response surface analysis method in order to minimize the temperature rise and thermal deformation. The hot judder analysis is done using the optimized disc, and the analysis results are discussed.

• Korea Journal of Hospital Management
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• v.15 no.3
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• pp.17-32
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• 2010

The purpose of this study is to analyze the influence of DISC behavior pattern, stress-managing method, and the stress level on job attitude of hospital Employees, and to provide suggestions for effective human resources management in hospital settings. First, the research suggested emotional or aversive stress-managing method had significant influence to the stress level, whereas DISC behavior patterns did not. Second, to the job satisfaction, Influence, Compliance and Steadiness of DISC behavior patterns, challenging or aversive stress-managing method, and the stress level showed immediate meaningful effect. Third, for the system immersion, challenging or emotional ress-managing method as well as the job satisfaction showed direct influence. Especially, the challenging method had not only a direct but an indirect effect through mediating job satisfaction.

• Annals of Clinical Neurophysiology
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• v.8 no.2
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• pp.193-195
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• 2006

Acute paraplegia attributable to disc herniation is known to occur most frequently at the thoracic level. A 50-year-old male presented with progressive limb weakness and hypoactive deep tendon reflexes. On the basis of clinical features and neurological findings, the diagnosis of Guillain-Barre syndrome was suspected. Spinal MRI showed cervical disc herniation. He underwent emergency surgery consisting of removal of herniated disc and anterior fusion. We emphasize that there is a possibility of acute progression of paralysis secondary to nontraumatic enlargement of cervical disc herniation.