• Journal of Chest Surgery
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• v.52 no.5
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• pp.335-341
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• 2019

Background: The endovascular approach to aortic disease treatment has been increasingly utilized in the past 2 decades. This study aimed to determine the long-term results of using the Seal thoracic stent graft. Methods: We retrospectively reviewed the outcomes of patients who underwent thoracic endovascular aortic repair or a hybrid procedure using the Seal thoracic stent graft (S&G Biotech, Seongnam, Korea) from January 2008 to July 2018 at a single institution. We investigated in-hospital mortality and the incidence of postoperative complications. We also investigated the mid-term survival rate and incidence of aorta-related complications. Results: Among 72 patients with stent grafts, 15 patients underwent the hybrid procedure and 21 underwent emergency surgery. The mean follow-up period was $37.86{\pm}30.73$ months (range, 0-124 months). Five patients (6.9%) died within 30 days. Two patients developed cerebrovascular accidents. Spinal cord injury occurred in 2 patients. Postoperative renal failure, postoperative extracorporeal membrane oxygenation support, and pneumonia were reported in 3, 1, and 6 patients, respectively. Stent-related aortic complications were observed in 5 patients (6.8%). The 1- and 5-year survival and freedom from stent-induced aortic event rates were 81.5% and 58.7%, and 97.0% and 89.1%, respectively. Conclusion: The use of the Seal thoracic stent graft yielded good mid-term results. Further studies are needed to examine the long-term outcomes of this device.

• Journal of the Korean Society of Radiology
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• v.13 no.1
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• pp.73-80
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• 2019

Neutrons are generated by the nuclear reaction, which is absorbed into the concrete wall and causes the activation during cyclotron operation. The purpose of this study is to investigate the effect of neutron activation and radiative concrete on concrete type. This experiment used Monte Carlo simulation and RESRAD model. The results of the experiment showed that the higher the content of Fe in concrete, the greater the shielding rate. The effect of $^{56}Fe(n,\;2np)^{54}Mn$ reaction on workers is also increased. However, radioactive nuclides have low activity and have very low impact on workers. Radioactive concrete should be treated as general wastes with less than its self-disposal tolerance level, and it should be recycled to the surface such as road repair rather than landfill to minimize the effect of $^{14}C$.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.2
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• pp.21-28
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• 2019

Handmade hydrated lime has been used for preservation and repair of architectural heritage in Korea. However, the effect of the amount of water used for slaking quicklime on the physical and chemical properties of the hydrated lime, which is the result of the slaking process, has not been clearly understood. In this study, particle size distribution, chemical composition and crystalline phases of the hydrated lime are investigated by varying the amount of water used for the slaking. In addition, temperature history during the slaking process is examined. For this, various experiments, such as laser diffraction analysis, X-ray fluorescence, X-ray diffraction, thermogravimetric analysis, and temperature recording using a thermocouple, were performed. When the quicklime came into contact with water, its temperature reached $100^{\circ}C$ within 10 min due to sudden exothermic reaction of calcium oxide, and this temperature was maintained for about 30 min. The water to lime ratio influenced the cooling rate during the slaking process; that is, the more water was used, the longer it took to reach an ambient temperature. The amount of water for the slaking did not have a noticeable effect on the contents of major components of the hydrated lime such as calcium hydroxide and calcium carbonate, but when slaked with more amount of water, average particle size of the lime tended to decrease. The experimental results in this study can be used as references for developing guidelines on the safety or appropriate amount of water in the lime slaking process.

• Journal of Trauma and Injury
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• v.34 no.2
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• pp.81-86
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• 2021

Purpose: This study investigated the clinical outcomes of trauma patients with blunt thoracic aortic injuries at a single institution. Methods: During the study period, 9,501 patients with traumatic aortic injuries presented to Trauma Center of Gil Medical Center. Among them, 1,594 patients had severe trauma, with an Injury Severity Score (ISS) of >15. Demographics, physiological data, injury mechanism, hemodynamic parameters associated with the thoracic injury according to chest computed tomography (CT) findings, the timing of the intervention, and clinical outcomes were reviewed. Results: Twenty-eight patients had blunt aortic injuries (75% male, mean age, 45.9±16.3 years). The majority (82.1%, n=23/28) of these patients were involved in traffic accidents. The median ISS was 35.0 (interquartile range 21.0-41.0). The injuries were found in the ascending aorta (n=1, 3.6%) aortic arch (n=8, 28.6%) aortic isthmus (n=18, 64.3%), and descending aorta (n=1, 3.6%). The severity of aortic injuries on chest CT was categorized as intramural hematoma (n=1, 3.6%), dissection (n=3, 10.7%), transection (n=9, 32.2%), pseudoaneurysm (n=12, 42.8%), and rupture (n=3, 10.7%). Endovascular repair was performed in 71.4% of patients (45% within 24 hours), and two patients received surgical management. The mortality rate was 25% (n=7). Conclusions: Traumatic thoracic aortic injuries are life-threatening. In our experience, however, if there is no rupture and extravasation from an aortic injury, resuscitation and stabilization of vital signs are more important than an intervention for an aortic injury in patients with multiple traumas. Further study is required to optimize the timing of the intervention and explore management strategies for blunt thoracic aortic injuries in severe trauma patients needing resuscitation.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.20 no.2
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• pp.109-116
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• 2010

We consider an information system where its throughput deteriorates due to security threats and evaluate information security investment portfolios. We assume that organizations adopt information security countermeasures (or portfolios consisted of countermeasures) to lessen the damage resulted from the productivity (or throughput) deterioration. A probability model is used to derive the system throughput and the average number of repairs according to the occurrence rate of security threats. Considering the revenue from throughput, the repair cost, and the investment for the security system, the net present value for each portfolio is derived. Organizations can compare information security investment portfolios and select the optimal portfolio.

• Journal of Microbiology and Biotechnology
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• v.32 no.2
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• pp.238-247
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• 2022

Since the skin covers most surfaces of the body, it is susceptible to damage, which can be fatal depending on the degree of injury to the skin because it defends against external attack and protects internal structures. Various types of artificial skin are being studied for transplantation to repair damaged skin, and recently, the production of replaceable skin using three-dimensional (3D) bioprinting technology has also been investigated. In this study, skin tissue was produced using a 3D bioprinter with human skin cell lines and cells extracted from mouse skin, and the printing conditions were optimized. Gelatin was used as a bioink, and fibrinogen and alginate were used for tissue hardening after printing. Printed skin tissue maintained a survival rate of 90% or more when cultured for 14 days. Culture conditions were established using 8 mM calcium chloride treatment and the skin tissue was exposed to air to optimize epidermal cell differentiation. The skin tissue was cultured for 14 days after differentiation induction by this optimized culture method, and immunofluorescent staining was performed using epidermal cell differentiation markers to investigate whether the epidermal cells had differentiated. After differentiation, loricrin, which is normally found in terminally differentiated epidermal cells, was observed in the cells at the tip of the epidermal layer, and cytokeratin 14 was expressed in the lower cells of the epidermis layer. Collectively, this study may provide optimized conditions for bioprinting and keratinization for three-dimensional skin production.

• Archives of Plastic Surgery
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• v.49 no.2
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• pp.174-183
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• 2022

Management of traumatic skull base fractures and associated complications pose a unique reconstructive challenge. The goals of skull base reconstruction include structural support for the brain and orbit, separation of the central nervous system from the aerodigestive tract, volume to decrease dead space, and restoration of the three-dimensional appearance of the face and cranium with bone and soft tissues. An open bicoronal approach is the most commonly used technique for craniofacial disassembly of the bifrontal region, with evacuation of intracranial hemorrhage and dural repair performed prior to reconstruction. Depending on the defect size and underlying patient and operative factors, reconstruction may involve bony reconstruction using autografts, allografts, or prosthetics in addition to soft tissue reconstruction using vascularized local or distant tissues. The vast majority of traumatic anterior cranial fossa (ACF) injuries resulting in smaller defects of the cranial base itself can be successfully reconstructed using local pedicled pericranial or galeal flaps. Compared with historical nonvascularized ACF reconstructive options, vascularized reconstruction using pericranial and/or galeal flaps has decreased the rate of cerebrospinal fluid (CSF) leak from 25 to 6.5%. We review the existing literature on this uncommon entity and present our case series of n = 6 patients undergoing traumatic reconstruction of the ACF at an urban Level 1 trauma center from 2016 to 2018. There were no postoperative CSF leaks, mucoceles, episodes of meningitis, or deaths during the study follow-up period. In conclusion, use of pericranial, galeal, and free flaps, as indicated, can provide reliable and durable reconstruction of a wide variety of injuries.

• Journal of Korean Academy of Nursing
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• v.52 no.6
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• pp.608-623
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• 2022

Purpose: This study aimed to evaluate the effects of a combined biofeedback and brief emotion regulation (C-BABER) program for sexually abused adolescents. Methods: This study employed a non-equivalent control group pretest-posttest design. The participants included 26 sexually abused adolescents from eight Sunflower Centers of South Korea-with 13 in the experimental group and 13 in the control group. The experimental group received four sessions of the individual C-BABER program, each lasting 60 minutes. Results: Compared with the control group, sexually abused adolescents in the experimental group exhibited significant score differences in traumatic symptoms, including depression (Z = - 2.24, p = .025), dissociation (Z = - 2.21, p = .027), anxiety (Z = - 2.02, p = .044), and posttraumatic stress (Z = - 2.01 p = .045); and impulsivity, including positive urgency (Z = - 3.35, p = .001) and negative urgency (Z = - 2.28, p = .023). Additionally, the experimental group exhibited significant score differences in meta-mood, including emotional attention (Z = - 2.45, p = .014), emotional clarity (Z = - 2.30, p = .021), and emotional repair (Z = - 2.28, p = .022); and emotional regulation modes, including emotional suppression (Z = - 2.65, p = .008) and cognitive reappraisal (Z = - 1.98, p = .047). Regarding bio-attention, significant changes were identified in the experimental group for the bio-attention rate and attention maintenance time in the posttest compared to the pretest (p = .001). Conclusion: The C-BABER program for sexually abused adolescents is effective in decreasing traumatic symptoms and impulsivity, and in improving meta-mood, emotional regulation mode, and bio-attention. Therefore, we recommend providing sexually abused adolescents the C-BABER program to help them regulate their emotions and effectively adapt to their lives.

• Steel and Composite Structures
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• v.45 no.3
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• pp.389-408
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• 2022

Residual capacity is defined as the load carrying capacity of an RC column after undergoing severe damage. Evaluation of residual capacity of RC columns is necessary to avoid damage initiation in RC structures. The central aspect of the current research is to propose an empirical formula to estimate the residual capacity of RC columns after undergoing severe damage. This formula facilitates decision making of whether a replacement or a repair of the damaged column is adequate for further use. Available literature mainly focused on the simulation of explosion loads by using simplified pressure time histories to develop residual capacity of RC columns and rarely simulated the actual explosive. Therefore, there is a gap in the literature concerning general relation between blast damage of columns with different explosive loading conditions for a reliable and quick evaluation of column behavior subjected to blast loading. In this paper, the Arbitrary Lagrangian Eulerian (ALE) technique is implemented to simulate high fidelity blast pressure propagations. LS-DYNA software is utilized to solve the finite element (FE) model. The FE model is validated against the practical blast tests, and outcomes are in good agreement with test results. Multivariate linear regression (MLR) method is utilized to derive an analytical formula. The analytical formula predicts the residual capacity of RC columns as functions of structural element parameters. Based on intensive numerical simulation data, it is found that column depth, longitudinal reinforcement ratio, concrete strength and column width have significant effects on the residual axial load carrying capacity of reinforced concrete column under blast loads. Increasing column depth and longitudinal reinforcement ratio that provides better confinement to concrete are very effective in the residual capacity of RC column subjected to blast loads. Data obtained with this study can broaden the knowledge of structural response to blast and improve FE models to simulate the blast performance of concrete structures.

• Journal of Dental Anesthesia and Pain Medicine
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• v.23 no.2
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• pp.111-116
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• 2023

We provided general anesthesia management to a patient with advanced atrioventricular block, which was discovered in the remote period after open-heart surgery. A 21-year-old man with Noonan syndrome was scheduled to undergo excision of a median intramandibular tumor. At 2 months of age, the patient underwent endocardial repair for congenital heart disease. During our preoperative examination, an atrioventricular block was detected, which had not been previously noted. Emergency drugs were administered, and a transcutaneous pacemaker was placed. During anesthesia induction, mask ventilation was easy, and intubation was performed smoothly using a video laryngoscope. The transcutaneous pacemaker was activated in demand mode at a pacing rate of 50 cycles/min approximately throughout the anesthesia time, and the hemodynamic status remained stable. The effect of intraoperatively administered atropine was brief, lasting only a few seconds. Although body movements due to thoracoabdominal muscle spasm were observed during pacemaker activation, they did not interfere with surgery. In postoperative patients with congenital heart disease, an atrioventricular block may be identified in the remote period, and preoperative evaluation should be based on this possibility. In addition, during anesthesia management, it is important to prepare multiple measures to maintain hemodynamic status.