• 디지털융복합연구
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• 제19권10호
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• pp.383-394
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• 2021

본 연구는 기술수용모델2(TAM2)를 적용하여 증강현실 애플리케이션 지속사용의도에 영향을 미치는 결정요인을 살펴보았다. 이를 위해 241명을 대상으로 설문조사를 실시하였고, SPSS 21.0과 AMOS 21.0 프로그램을 이용하여 확인적 요인분석과 상관관계분석, 경로분석 등을 실시하여 주요 결과를 도출하였다. 그 결과를 제시하면, 사용자의 증강현실 애플리케이션에 대한 인터페이스와 상호작용성, 상대적 이점은 지각된 유용성에, 기술적 자기효능감은 지각된 유용성과 지각된 용이성에 긍정적 영향을 미친 것으로 나타났다. 또한 지각된 용이성은 지각된 유용성에 긍정적 영향을 미쳤으며, 지각된 유용성과 지각된 용이성 모두는 지속사용의도에 긍정적 영향을 미치는 것으로 나타났다. 한편, 본 연구의 학술적 시사점으로는 증강현실 애플리케이션을 적용하여 기술수용모델2를 실증적으로 검증하였다는 점에서 의의가 있으며, 실무적으로는 증강현실 애플리케이션을 개발하고, 수용성의 지속성을 확보하기 위해서는 관련 기업이나 개발자들이 어떤 부분을 중점적으로 고려해야 하는지를 실증적으로 확인하였다는 점에서 의의가 있다. 향후 연구에서는 교육이나 게임분야를 적용하여 증강현실 애플리케이션의 사용자 효과를 검증할 필요가 있을 것이다.

• Archives of Pharmacal Research
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• 제19권4호
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• pp.286-291
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• 1996

Phenolic compounds are prevalent as toxins or environmental pollutants, but they are also widely used as drugs for various purpose including anticancer agent. A novel biphenolic compound, bis(2-hydroxy-3-tert-butyl-5-methylphenyl)methane (GERI-BPO02-A) was isolated from the fermentation broth of Aspergillus fumigatus F93 previously, and it has revealed cytotoxicity against human solid tumor cells. Its effective doses that cause 50% inhibition of cell growth in vitro against non-small cell lung cancer cell A549, ovarian cancer cell SK-OV-3, skin cancer cell SK-MEL-2 and central nerve system cancer cell XF498 were 8.24, 10.60, 8.83, $9.85\mug/ml$ respectively. GERI-BPO02-A has also revealed cytotoxicity against P-glycoproteinexpressed human colon cancer cell HCT15 and its multidrug-resistant subline HCT15/CL02, and its cytotoxicity was not affected by P-glycoprotein. We have also tested cytotoxicities of structurally related compounds of GERI-BPO02-A such as diphenylmethane, 1,1-bis(3,4dimethylphenyl)ethane, 2,2-diphenylpropane, 2-benzylpyridine, 3-benzylpyridine, $4,4^I-di-tert-butylphenyl$, bibenzyl, $2,2^I-dimethylbibenzyl$, cis-stilbene, trans-stilbene, 3-tert-butyl-4-hydroxy-5-methylphenyisulfide, sulfadiazine and sulfisomidine for studying of structure and activity relationship, and from these data we could suppose that hydroxyl group of GERI-BPO02A conducted important role in its cytotoxicity.

• 대한두개안면성형외과학회지
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• 제10권2호
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• pp.86-90
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• 2009

Purpose: Inferior blow-out fracture is the common facial fracture. Unsatisfactory functional and aesthetic outcomes are frequent when it is treated inappropriately. If fractures are extended and reach the posterior end of orbital floor, enophthalmos frequently followed as complication. The purpose of this study was to evaluate reduction technique of extensive inferior blow-out fracture with ballooning of foley catheter through endoscopic transnasal approach and implantation of $Medpor^{(R)}$ through subciliary approach. Methods: A retrospective study was performed on 14 patients with extensive inferior blow-out fracture who underwent ballooning of foley catheter through endoscopic transnasal approach with implantation of $Medpor^{(R)}$ through subciliary approach. Patients were operated from May 2005 to November 2007. Data for 14 patients were acquired from patient's charts. Preoperative and postoperative data for enophthalmos, diplopia, limitation of extraocular motion were reviewed. Preoperative and postoperative CT scan were also checked. The patients were followed up from 4 to 18 months. Results: The enophthalmos was corrected in all patients. Among 7 patients with diplopia preoperatively, diplopia was resolved in three patients postoperatively. The diplopia persisted in four patients and two of them also had limitation of extraocular motion postoperatively. The limitation of extraocular motion occurred in seven patients preoperatively. But five patients recovered after operation immediately. These symptoms were resolved about three months after the operation. Conclusion: The ballooning of foley catheter through endoscopic transnasal approach with implantation of $Medpor^{(R)}$ through subciliary approach can be considered one of the appropriate technique for extensive inferior blowout fracture.

• Archives of Plastic Surgery
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• 제43권6호
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• pp.575-581
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• 2016

Background Open thyroidectomy is conventionally performed at the anterior side of neck, which is a body part with a comparatively great degree of open exposure; due to this, postoperative scarring may cause distress in patients. We aimed to compare the effects of ablative and nonablative fractional laser treatments on thyroidectomy scars. We examined medical records in a retrospective manner and analyzed scars based on their digital images by using the modified Manchester Scar Scale (mMSS). Methods Between February 2012 and May 2013, 55 patients with thyroidectomy scars were treated with ablative (34 patients) or nonablative (21 patients) fractional laser. Each patient underwent 4 laser treatment sessions in 3-4 week intervals, 1-2 months postoperatively. Scar improvement was assessed using patient images and the mMSS scale. Results The mean decrease in scar score was 3.91 and 3.47 in the ablative and nonablative groups, respectively; the reduction between 2 groups did not exhibit any significant difference (P=0.16). We used the scale once again to individually evaluate scar attributes. The nonablative group accounted for a considerably higher color score value (P=0.03); the ablative group accounted for a considerably higher contour score value (P<0.01). Patient satisfaction was high and no complications occurred. Conclusions Both types of fractional laser treatments can be used successfully for thyroidectomy scar treatment with minimal complications; however, results indicate that higher effectiveness may be obtained from the use of ablative and nonablative lasers for hypertrophic scars and early erythematous scars, respectively. Therefore, the appropriate laser for scar treatment should be selected according to its specific characteristics.

• Archives of Plastic Surgery
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• 제36권3호
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• pp.294-298
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• 2009

Purpose: The pharyngeal flap is one of the popular surgical method to treat the problem of velopharyngeal dysfunction. This study evaluated speech outcomes of patients who underwent superiorly based pharyngeal flap surgery based on timing of surgery. Methods: A restrospective review of 50 patients who underwent pharyngeal flap surgery for velopharyngeal insufficiency between September 1996 and January 2008 was undertaken. Thirty patients with an available preoprative and postoperative speech assessments with at least 6 months of follow-up were included in this study. We checked out the significance of speech improvement after surgery analysing preoperative and postoperative scoring of speech assessment. We also investigated the direct relationship between the age at surgery and the degree of speech improvement, and the improvement score in different age groups. Results: The mean score of preoperative speech was $52.6{\pm}7.4points$ and postoperative speech was $58.6{\pm}6.5points$, which presented significant postoperative speech improvement with an average of 5.9 points(p<0.01). There was a significant inverse relationship between the age at operation and speech improvement degree(p<0.01, r = -0.54). Comparing the age groups, the age group of 4 to 5 years presented statistically significant speech improvement(p<0.01). Conclusion: we propose that all patients indicated should take pharyngeal flap irrespective of age. In this study, the younger the age at surgery, the higher degree of speech improvement, for which we suggest that surgical approach should be undertaken as early as possible, especially younger than age 5 years.

• 펄프종이기술
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• 제41권4호
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• pp.73-81
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• 2009

The document archives like official documents, books, maps and historic paper artifacts are primarily based on the organic cellulosic materials. As the passage of time, these organic cellulosic materials are slowly deteriorated by various aging factors, like light, polluted air and biological fungi. Many researchers have been carried out the examination method of deteriorating origins, the mechanism of aging hysteresis, and the preserving method of archival materials. One of the most simple and easiest ways for conservation of organic archival documents is the proper storage under environmental control. Corrugated board for archival quality container has been developed and already used in advanced country, like Japan, USA, German, UK and Europe. In case of Korea, corrugated board for archival quality container has been used a decade ago, but totally imported. This study was tried to develop the corrugated board for archival quality container. Liner and corrugated medium were specially produced and finally manufactured to E flute corrugated board. The physical and strength properties of permanent base paper and corrugated board were evaluated, and compared with imported corrugated board. 4 kinds of corrugating adhesives were considered various in order to investigate optimum adhesive for flute development between liner and corrugating medium, and evaluate adhesion strength under conditions of storage and curing temperatures.

• Archives of Pharmacal Research
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• 제28권6호
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• pp.685-690
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• 2005

We recently reported that the ginseng saponin metabolite, compound K (20-O-$\beta$-D-glucopyra-nosyl-20(S)-protopanaxadiol, IH901), inhibits the growth of U937 cells through caspase-dependent apoptosis pathway. In this study, we further characterized the effects of compound K on U937 cells and found that, in addition to apoptosis, compound K induced the arrest of the G1 phase. The compound K treated U937 cells showed increased p21 expression; an inhibitory protein of cyclincdk complex. The up-regulation of p21 was followed by the inactivation of cyclin D and the cdk4 protein, which act at the early $G_1$ phase, and cyclin E, which acts at the late $G_1$ phase. Furthermore, compound K induced the activation of JNK and the transcription factor AP-1, which is a downstream target of JNK. These findings suggest that the up-regulation of p21 and activation of JNK in the compound K treated cells contribute to the arrest of the $G_1$ phase.

• 대한두개안면성형외과학회지
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• 제10권1호
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• pp.1-6
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• 2009

Purpose: This study presents a classification of pure medial and inferior blow-out fracture, and confirms the relationship between the types of fractures, postoperative complications and operative methods. Methods: Sixty patients were treated by transnasal endoscopic reduction with $Medpor^{(R)}$ implantation through subciliary incision and foley catheter insertion into maxillary sinus was done if there was extensive orbital floor fracture. Fractures were classified by number of coronal sections from posterior margin of fossa for lacrimal sac to orbital apex in CT. Type I is defined when the medial wall fracture is over 50% and inferior wall fracture below 50%. Type II, when below 50% medial wall fracture and over 50% floor fracture were present. If there were both over 50%, it was classified as Type III and both below 50% for Type IV. Extreme fracture involving orbital buttress was Type V and postoperative findings in all patients were examined. Results: Type I and V were most common and preoperative findings were more likely to present according to extent of inferior fracture. Diplopia remained in 2 cases after additional insertion of foley catheter, but enophthalmos over 2 mm were presented in 3 cases and diplopia in 3 cases were observed who were not treated with foley catheter. Conclusion: Postoperative complications were increased according to extent of fracture, especially buttress involvement. Additional insertion of foley catheter proved its effectiveness in decreasing postoperative complications.

• 대한두개안면성형외과학회지
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• 제21권4호
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• pp.237-243
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• 2020

Background: The scalp is an important functional and aesthetic structure that protects the cranial bone. Due to its inelastic characteristics, soft-tissue defects of the scalp make reconstruction surgery difficult. This study aims to provide an improved scalp reconstruction decision making algorithm for surgeons. Methods: This study examined patients who underwent scalp reconstruction within the last 10 years. The study evaluated several factors that surgeons use to select a given reconstruction method such as etiology, defect location, size, depth, and complications. An algorithmic approach was then suggested based on an analysis of these factors. Results: Ninety-four patients were selected in total and 98 cases, including revision surgery, were performed for scalp reconstruction. Scalp reconstruction was performed by primary closure (36.73%), skin graft (27.55%), local flap (17.34%), pedicled regional flap (15.30%), and free flap (3.06%). The ratio of primary closure to more complex procedure on loose scalps (51.11%) was significantly higher than on tight scalps (24.52%) (p=0.011). The choice of scalp reconstruction method was affected significantly by the defect size (R=0.479, p<0.001) and depth (p<0.001). There were five major complications which were three cases of flap necrosis and two cases of skin necrosis. Hematoma was the most common of the 29 minor complications reported, followed by skin necrosis. Conclusion: There are multiple factors affecting the choice of scalp reconstruction method. We suggest an algorithm based on 10 years of experience that will help surgeons establish successful surgical management for their patients.

• Archives of Reconstructive Microsurgery
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• 제9권1호
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• pp.27-36
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• 2000

February 1995 to September 1999, authors have experienced seven cases of infected nonunion of tibial fractures with associated soft tissue injury and skin defect, and have accomplished union in all cases by free vascularized fibular graft. All grafts healed with no radiographic evidence of bone necrosis or resorption and have been able to treat large bony defect and skin defect simultaneously. In this study, five cases of vascularized free fibular osteocutaneous flap transfer and two cases of free fibular graft are reported. All of seven cases were infected nonunion of tibia. The results were obtained as follows 1) The mean duration of the radiologic bone union was average 5.3months. 2) Grafted fibular has been hypertrophied, average 10.6 months. 3) In five cases of preservation of posterior cortex of tibia, bony union and hypertrophy of grafted bone were earlier than that two cases of complete segmental resection of tibia. 4) In two cases which only free vascularized fibular graft were performed because achievement of cutaneous flap was failed, authors found that soft tissue defect was filled with granulation tissue and split-thickness skin graft was possible over the granulation tissue after 3 weeks postoperatively.