• International Journal of Stem Cells
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• v.11 no.2
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• pp.177-186
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• 2018

Background and Objectives: Glial scarring and inflammation after spinal cord injury (SCI) interfere with neural regeneration and functional recovery due to the inhibitory microenvironment of the injured spinal cord. Stem cell transplantation can improve functional recovery in experimental models of SCI, but many obstacles to clinical application remain due to concerns regarding the effectiveness and safety of stem cell transplantation for SCI patients. In this study, we investigated the effects of transplantation of human mesenchymal stem cells (hMSCs) that were genetically modified to express Olig2 in a rat model of SCI. Methods: Bone marrow-derived hMSCs were genetically modified to express Olig2 and transplanted one week after the induction of contusive SCI in a rat model. Spinal cords were harvested 7 weeks after transplantation. Results: Transplantation of Olig2-expressing hMSCs significantly improved functional recovery in a rat model of contusive SCI model compared to the control hMSC-transplanted group. Transplantation of Olig2-expressing hMSCs also attenuated glial scar formation in spinal cord lesions. Immunohistochemical analysis showed that transplanted Olig2-expressing hMSCs were partially differentiated into Olig1-positive oligodendrocyte-like cells in spinal cords. Furthermore, NF-M-positive axons were more abundant in the Olig2-expressing hMSC-transplanted group than in the control hMSC-transplanted group. Conclusions: We suggest that Olig2-expressing hMSCs are a safe and optimal cell source for treating SCI.

• Phonetics and Speech Sciences
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• v.14 no.4
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• pp.35-43
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• 2022

This paper studies how to improve the identification rate of laryngeal disability speech data by convolutional neural network (CNN) and machine learning ensemble learning methods. In general, the number of laryngeal dysfunction speech data is small, so even if identifiers are constructed by statistical methods, the phenomenon caused by overfitting depending on the training method can lead to a decrease the identification rate when exposed to external data. In this work, we try to combine results derived from CNN models and machine learning models with various accuracy in a multi-voting manner to ensure improved classification efficiency compared to the original trained models. The Pusan National University Hospital (PNUH) dataset was used to train and validate algorithms. The dataset contains normal voice and voice data of benign and malignant tumors. In the experiment, an attempt was made to distinguish between normal and benign tumors and malignant tumors. As a result of the experiment, the random forest method was found to be the best ensemble method and showed an identification rate of 85%.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.14 no.2
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• pp.83-87
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• 2003

Background and Objectives : Sphincteric function of the larynx, essential to lower airway protection, is most efficiently achieved through strong reflex adduction by both vocal cords. We hypothesize that central facilitation is an essential component of a bilateral adductor reflex and that its disturbance could result in weakened sphincteric closure. Materials and Method : Seven adult 20kg dogs underwent evoked response laryngeal electromyoraphy under 0.5 to 1.0 MAC isoflurane anesthesia. The internal branch of superior laryngeal nerve was stimulated through bipolar platinum-iridium electrodes and recording electrodes were positioned in the ipsilateral and contralateral thyroaryteonoid muscles. Results : Consistent threshold responses were obtained ipsilaterally under all anesthetic levels. However, contralateral reflex responses disappeared as anesthetic levels approached 1.0 MAC. Additionally, at 0.5 MAC, late responses (R2) were detected in one animal. Conclusion : Alteration of central facilitation by deepening anesthesia abolishes the crossed adductor reflex, predisposing to a weakened glottic closure response. Precise understanding of this effect may improve the prevention of aspiration in patients emerging from prolonged sedation or under heavy psychotropic control.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.25 no.1
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• pp.36-38
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• 2014

The patient suffered cardiac arrest 8 months before presentation. She has been suffering hoarseness and exertional dyspnea and nocturnal stridor. Upon flexible laryngoscopy, her vocal cords showed no motion and fixed in paramedian position. There was no causal finding on neck CT. EMG showed some muscular activity. Under the suspicion of crico arytenoid fixation, we performed suspension laryngoscopy, and found the arytenoid cartilage was fixed with short and stout scar, which was removed with scissors. Just after surgery she regained her voice and respiration.

• Textile Coloration and Finishing
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• v.22 no.4
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• pp.300-305
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• 2010

Poly(ethylene terephthalate)(PET) tire cord has relatively lower adhesion properties caused by limited reacting sites. In order to improve the adhesion force between PET tire cord and rubber, an additional process to activate surface of PET has been employed. Atmospheric plasma was used to substitute the chemical finishing process of PET tire cord as a green dipping process. Contact angle was measured to confirm surface change of PET after plasma treatment. The treated PET tire cords with/without resorcinol-formaldehyde-latex(RFL) and unvulcanized rubber were vulcanized in a testing mold at $160^{\circ}C$. After atmospheric plasma treatment of PET tire cord, adhesion force was somewhat increased under some conditions.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.5 no.1
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• pp.64-68
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• 1994

Anterior glottic webs shorten the free margins of the vocal cords and prevent air flow at their locations, thereby changing the potential vibratory characteristics of the vocal system. They are now more often iatrogenic from endolaryngeal surgical procedures, complications of intubation, chronic inflammation or due to penetrating and blunt trauma to the larynx. A wide range of treatment procedures are now available but the solution to acquiring a "normal" voice has remained elusive due to reflectory stenosis and scar formation. We present our recent experiences with glottic web in nine cases using KTP-532 laser vaporization and endolaryngeal silastic keel insertion technique. Postoperative speech assessment in our cases showed significant improvement in voice quality of 7 of 9 cases studied(77.8%), and no specific problems were not seen.

• Elastomers and Composites
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• v.16 no.4
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• pp.211-216
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• 1981

A series of conveyer rubber belts has been made by blending natural rubber(NR), styrene butadiene rubber(SBR), chloroprene rubber(CR) and additives on nylon cords, and their respective flammability has been investigated. It has been observed that: 1. By adding an antiflame agent to the belt, in addition to 70% chlorinated paraffine and antimony oxide($Sb_{2}O_{3}$), the inflammability is improved remarkably to O - 2 seconds due to the synergistic effect, while a sample without antiflame B fails to pass the KS M 6678 test. 2. Physical properties, such as tensile strength, elongation at break and adhesion strength, of the sample belts have been studies by varying ratios of NR/CR from 20 to 100, and it has been observed that the higher ratios have the better physical properties.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.12
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• pp.2543-2548
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• 2011

The Smoke Detect System is setup to extinguish early a fire on the large ship like as the cargo ship and Bulk Carrier at sea. The Addressable Type Smoke Detect System that keeps the advantages and dispenses with the disadvantages of the existing conventional type system is composed of only one electrical cords. In this paper, we make the Smoke Detect System of an addressable type and implement to control it using ATmega Micro-controller and evaluate it.

• Proceedings of KOSOMES biannual meeting
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• 2003.05a
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• pp.153-158
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• 2003

Design of general steel structure had applied and achieve elastic design concept mainly so far. Because elastic design supposes that whole structure complies with elasticity formula as that achieve via allowable stress of material is concept that calculate stress distribution of construction about action external load and estimate load of when the maximum stress reaches equally with allowable stress that is established beforehand by maximum safety load of the structure. But, absence that compose actuality structure by deal with external load increase small success surrender and structure hardness falls and tell structure in limit state finally on the whole as showing complicated conduct by interference between these breakdown at buckling by compression. Examined closely about conduct of place since initial buckling through carbon vocal cords transformation finite element analysis series (ANSYS) that place mending condition supposes case that is boundary condition in this investigation.

• Korean Journal of Veterinary Research
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• v.57 no.2
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• pp.131-133
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• 2017

A 11-year-old, female Russian Blue cat was presented with anorexia, vomiting, and diarrhea lasting for 3 days. Abdominal ultrasonography revealed a hypoechoic, non-circumferential, and eccentrically formed intestinal loop with altered wall layering and thickening of the tunica muscularis. After surgical resection, histopathologic examination confirmed an infiltrative, round-cell neoplasm composed of sheets and cords of neoplastic mast cells within a fibrotic, edematous stroma. The cat was alive and healthy 6 months after surgery. To the best of our knowledge, this is the first reported case of an intestinal mast cell tumor in a Russian Blue cat in South Korea.