• Archives of Craniofacial Surgery
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• v.13 no.2
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• pp.139-142
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• 2012

Purpose: To reconstruct the midface, local flaps such as nasolabial flaps have been frequently used. These local flaps, however, have the shortcomings of requiring a secondary operation or limitations in the movement of the flap. Thus, new methods have been developed. This paper reports a case wherein the basal cell carcinoma on the cheek was resected and the skin and soft tissue defect was successfully treated using a facial artery perforator flap. Methods: A 68-year-old female consulted the authors on the basal cell carcinoma that developed on her cheek. The mass was fully resected and revealed a $2.3{\times}2.3cm$ defective region. Using a Doppler ultrasonography, the facial artery path was traced, and using a loupe magnification, the facial artery perforator flap was elevated and the defective region was covered with the flap. Results: The flap developed early venous congestion, but it disappeared without any treatment. Six months after the surgery, the patient was satisfied with the postoperative result. Conclusion: The facial artery perforator flap has a thin pedicle. It offers a big arc of the rotation that allows free movement and one-stage operation. These strengths make the method useful for the reconstruction of the midface among other procedures.

• Archives of Plastic Surgery
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• v.37 no.1
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• pp.95-98
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• 2010

Purpose: One of the most common cause of upper extremity lymphedema is breast cancer surgery. We experienced the nerve entrapment syndrome which was associated with postmastectomy lymphedema. To the best of our knowledge, this is the first case report of lymphedema induced nerve entrapment syndrome on upper extremity in Korea. Methods: A 54-year-old woman presented with a tingling sensation on her right hand, which had been present for 1 year. On her history, she had a postmastectomy lymphedema on her right upper extremity for 20 years. Initial electromyography (EMG) showed that the ampulitude of the median, ulnar, and dorsal ulnar cutaneous nerve were decreased, and conduction block was also seen in median nerve across the wrist. In needle EMG, incomplete interference patterns were observed in the muscles innervated by median and ulnar nerves. In conclusion, electrophysiologic study and clinical findings suggested right median and ulnar neuropathy below the elbow. Therefore, we performed surgical procedures, which were release of carpal tunnel, Guyon's canal, and cubital tunnel. Results: The postoperative course was uneventful until the first two years. The tingling sensation and claw hand deformity were improved, however, the motor function decreased progressively. In 7 years after the operation, patient could not flex her wrist and thumb sufficiently. EMG which was performed recently showed that ulnar motor response was of low ampulitude. Moreover, median, ulnar, dorsal ulnar cutaneous, lateral antecubital cutaneous and median antebrachial cutaneous sensory response were unobtainable. Abnormal spontaneous activities were observed in upper arm muscles. In conclusion, multiple neuropathies were eventually developed at above elbow level. Conclusion: On treating nerve entrapments associated with lymphedema, medical professionals should be fully aware of the possibility of unpredictable results after the surgery, because of the pathophysiologic traits of chronic lymphedema.

• Archives of Plastic Surgery
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• v.36 no.1
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• pp.66-74
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• 2009

Purpose: The importance of the deformities in alar - columellar complex has been underestimated in Asian ethnic groups for the last decades. Fortunately, with increasing familiarity of the open rhinoplasty techniques, the anatomic details of the nasal tip have been pointed up. Definitely, having an interest and demand for improving the sub - normal relationship between the alar rim and columella are indebted for such growing of knowledge about nasal tip anatomy. However, it is true that any single procedure is not settled as versatile and fully confident modality to correct the retracted notching of the alar rim. With this article, I should like to propose another useful option for treating retracted ala. Methods: The author has tried to correct alar rim retraction by means of: (1) Triangular onlay septal cartilage graft on the lower lateral cartilage with the medial end fixed to the anterior surface of the lateral crus(Alar extension graft), (2) Inserting lateral end of the alar extension graft to the vestibular skin pocket in the form of a finger - in - groove, (3) using the vestibular skin in the form of an advancement flap, and (4) using the soft shield graft to prevent possible visible step - off of the alar margin. Results: The author applied an alar extension graft to 16 patients in order to correct a retracted ala for the last 27 months (August, 2003 - October, 2005). The distances from alar rim to long axis of nostril were improved to be within 2 mm in all of the cases, and also the shape of the alar rim changed to a round form. Nostril asymmetry (6%) in one case, temporary palpable step - off (18%) in three cases, temporary visible step - off (6%) in one case, and temporary paresthesia of the tip (25%) in four cases were observed. Conclusion: The alar extension graft is simple and efficacious. It does not need donor sites other than the operative field, and its results are predictable. In particular, since it may give structural intensity to a weak lower lateral cartilage, it may be preferentially used for the correction of a retracted ala that arises from hypoplastic lower lateral cartilage. Moreover intensified lower lateral cartilage also improves the esthetic shape of lobule.

• Geomechanics and Engineering
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• v.9 no.3
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• pp.373-395
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• 2015

Comprehensive results from cyclic plate loading at a diameter of 300 mm supported by layers of geocell are presented. The plate load tests were performed in a test pit measuring $2000{\times}2000mm$ in plane and 700 mm in depth. To simulate half and full traffic loadings, fifteen loading and unloading cycles were applied to the loading plate with amplitudes of 400 and 800 kPa. The optimum embedded depth of the first layer of geocell beneath the loading plate and the optimum vertical spacing of geocell layers, based on plate settlement, are both approximately 0.2 times loading plate diameter. The results show that installation of the geocell layers in the foundation bed, increase the resilient behavior in addition to reduction of accumulated plastic and total settlement of pavement system. Efficiency of geocell reinforcement was decreased by increasing the number of the geocell layers for all applied stress levels and number of cycles of applied loading. The results of the testing reveal the ability of the multiple layers of geocell reinforcement to 'shakedown' to a fully resilient behavior after a period of plastic settlement except when there is little or no reinforcement and the applied cyclic pressure are large. When shakedown response is observed, then both the accumulated plastic settlement prior to a steady-state response being obtained and the resilient settlements thereafter are reduced. The use of four layers of geocell respectively decreases the total and residual plastic settlements about 53% and 63% and increases the resilient settlement 145% compared with the unreinforced case. The inclusion of the geocell layers also reduces the vertical stress transferred down through the pavement by distributing the load over a wider area. For example, at the end of the load cycle of the applied pressure of 800 kPa, the transferred pressure at the depth of 510 mm is reduced about 21.4%, 43.9%, 56.1% for the reinforced bases with one, two, and three layers of geocell, respectively, compared to the stress in the unreinforced bed.

• Steel and Composite Structures
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• v.23 no.4
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• pp.473-481
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• 2017

Steel plate shear wall (SPSW) system has been increasingly used for lateral loads resisting system since 1980s when the utilization of post-buckling strength of SPSW was realized. The structural response of SPSWs largely depends on the behavior of the surrounded beams. The beams are normally required to behave in the elastic region when the SPSW fully buckled and formed the tension field action. However, most modern design codes do not specify how this requirement can be achieved. This paper presents theoretical investigation and design procedures of manually calculating the plastic flexural capacity of the beams of SPSWs and can be considered as an extension to the previous work by Qu and Bruneau (2011). The reduction in the plastic flexural capacity of beam was considered to account for the presence of shear stress that was altered towards flanges at the boundary region, which can be explained by Saint-Venant's principle. The reduction in beam web was introduced and modified based on the research by Qu and Bruneau (2011), while the shear stress in the web in this research is excluded due to the boundary effect. The plastic flexural capacity of the beams is given by the superposition of the contributions from the flanges and the web. The developed equations are capable of predicting the plastic moment of the beams subjected to combined shear force, axial force, bending moment, and tension fields induced by yielded infill panels. Good agreement was found between the theoretical results and the data from previous research for flexural capacity of beams.

• Earthquakes and Structures
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• v.26 no.3
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• pp.175-189
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• 2024

Aiming at studying the plastic hinge (PH) evolution regularities and failure mode of rocking wall moment frame (RWMF) structure in earthquakes, the whole-working history analysis of seismic performance state of RWMF structure based on co-operation performance and PH evolution was carried out. Building upon the theoretical analysis of the elastic internal forces and deformations of RWMF structures, nonlinear finite element analysis (FEA) methods were employed to perform both Pushover analysis and seismic response time history analysis under different seismic coefficients (δ). The relationships among PH occurrence ratios (R_ph), inter-story drifts and δ were established. Based on the plotted curve of the seismic performance states, evaluation limits for the R_ph and inter-story drifts were provided for different performance states of RWMF structures. The results indicate that the R_ph of RWMF structures exhibits a nonlinear evolution trend of "fast at first, then slow" with the increasing of δ. The general pattern is characterized by the initial development of beam hinges in the middle stories, followed by the development towards the top and bottom stories until the beam hinges are fully formed. Subsequently, the development of column hinges shifts from the bottom and top stories towards the middle stories of the structure, ultimately leading to the loss of seismic lateral capacity with a failure mode of partial beam yield, demonstrating a global yielding pattern. Moreover, the limits for the R_ph and inter-story drifts effectively evaluate the five different performance states of RWMF structures.

• Archives of Plastic Surgery
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• v.47 no.3
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• pp.217-222
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• 2020

Background Surgical reconstruction of chronic wounds is often infeasible due to infection, comorbidities, or poor viability of local tissues. The aim of this study was to describe the authors' technique for improving the regenerative and antimicrobial potential of a combination of modified nanofat and platelet-rich plasma (PRP) in nonhealing infected wounds. Methods Fourteen patients met the inclusion criteria. Fat tissue was harvested from the lower abdomen following infiltration of a solution of 1,000 mL of NaCl solution, 225 mg of ropivacaine, and 1 mg of epinephrine. Aspiration was performed using a 3-mm cannula with 1-mm holes. The obtained solution was decanted and mechanically emulsified, but was not filtered. Non-activated leukocyte-rich PRP (naLR-PRP) was added to the solution before injection. Patients underwent three sessions of injection of 8-mL naLR-PRP performed at 2-week intervals. Results Thirteen of 14 patients completed the follow-up. Complete healing was achieved in seven patients (53.8%). Four patients (30.8%) showed improvement, with a mean ulcer width reduction of 57.5%±13.8%. Clinical improvements in perilesional skin quality were reported in all patients, with reduced erythema, increased thickness, and increased pliability. An overall wound depth reduction of 76.6%±40.8% was found. Pain was fully alleviated in all patients who underwent re-epithelization. A mean pain reduction of 42%±33.3% (as indicated by visual analog scale score) was found in non-re-epithelized patients at a 3-month follow-up. Conclusions The discussed technique facilitated improvement of both the regenerative and the antimicrobial potential of fat grafting. It proved effective in surgically-untreatable infected chronic wounds unresponsive to conventional therapies.

• Journal of the Korean Society of Safety
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• v.32 no.1
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• pp.66-74
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• 2017

Masonry walls which are commonly used for partitions in low-rise reinforced concrete (RC) structures, can be easily exposed to high risks under strong earthquakes. Since the strength degradations cannot be protected under the ground motions, their applications cannot be recommended for building structures which are designed to possess high seismic performances. However, masonry-infilled walls are typically considered as non-structural elements in evaluating the seismic performance of building structures. In order to figure out this problem, this study performed experiments using two specimens-only RC frame and RC frame infilled with masonry walls- under static loading. Also, the study established analytical models representing fully infilled frames and bare frame, and compared their structural behavior with test results. In addition, analytical model representing partially infilled frames was established and analyzed. Test results indicated that strength and energy dissipating capacity were increased for IW-RN(fully infilled frames) compared to the NW(bare frame). The nonlinear static analysis of the three specimens was also conducted using the inelastic plastic hinge frame element and diagonal strut models, and the analytical results successfully simulated the nonlinear behaviour of the specimens in accordance with the test results.

• Journal of the Korean Burn Society
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• v.22 no.2
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• pp.30-33
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• 2019

Purpose: Wound healing and scar management of donor site after skin graft should not be overlooked. Patients continue to complain of dryness, itching sensation. Such discomfort can cause irritation to the patients and lead to delayed healing or secondary infection. Thus, the author predicted Eucalyptus Oil, which acts on Transient Receptor Potential Melastatin 8 would be effective in regulating scar by reducing itching sensation in donor site when combining conventional silicone materials. Methods: The study was performed on 30 patients who underwent split thickness skin graft with lateral thigh as donor site between January 2017 and August 2018. First, primary evaluation of fully epithelized donor site scar three weeks after surgery was conducted. Control group (n=15) applied silicone gel (Kelo-cote, USA) solely two times a day. study group (n=15) applied Eucalyptus oil, combined with silicone gel. After 3 months of follow up, donor scar was evaluated using Vancouver scar scale and VAS scores of subjective patient reports regarding pain and itching sensation. Results: It was confirmed that both groups showed stable scar improvement comparing scar quality for 3 months. After 3 months, scar quality in study group showed superiority in pigmentation, pliability and pruritus compared to control group. Conclusion: Application of Eucalyptus Oil combined with conventional silicone gel is favorable to scar management and may give additional benefit of alleviating pruritis symptoms.

• Journal of Korean Society of Steel Construction
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• v.25 no.1
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• pp.103-114
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• 2013

Recently, there is a growing interest on sustainable connection system that makes it possible to reuse of main structural members by concentrating most of the damage in the frame caused by strong horizontal force, such as earthquake, to damper. In this study proposed a new type of damage-controlled connection system applying these concepts and analysed the major structural performance of the proposed system through the full-scale cyclic loading test and nonlinear finite element analyses. According to the result, it derived the optimal damper/beam strength ratio that minimize the damage of main members and satisfy at least the fully plastic moment of the beam. And it was to verify the possibility of applying as seismic connection details.