• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.17 no.1
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• pp.59-66
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• 2024

In this paper, the method to design the antenna, which is suitable for an impulse-like waveform radiation, is presented. In general, the impulse-like waveform has its spectrum of around sub GHz bandwidth and the antenna should be properly designed for not only operating wide-bandwidth also reflecting the time domain characteristics for near-zone impulse radar applications. In this regard, Vivaldi antenna has been designed and characterized in terms of short-pulse radiating aspects in the time domain and verified by measured results. The designed antenna has shown to be operating within wide-bandwidth and to be stable for the input impedance from 1.8 to more than 10GHz. The far-zone radiating waveform has been investigated on each plane at the interval of 30degree and the designed antenna has shown to be a directive characteristic. It can be seen that those results proposed are widely applicable to the near area sensing applications such as ground-penetrating radar.

• Journal of Veterinary Science
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• v.25 no.1
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• pp.12.1-12.10
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• 2024

Background: Staphylococcus aureus and S. pseudintermedius are the major etiological agents of staphylococcal infections in humans, livestock, and companion animals. The misuse of antimicrobial drugs has led to the emergence of antimicrobial-resistant Staphylococcus spp., including methicillin-resistant S. aureus (MRSA) and methicillin-resistant S. pseudintermedius (MRSP). One novel therapeutic approach against MRSA and MRSP is a peptide nucleic acid (PNA) that can bind to the target nucleotide strands and block expression. Previously, two PNAs conjugated with cell-penetrating peptides (P-PNAs), antisense PNA (ASP)-cmk and ASP-deoD, targeting two essential genes in S. aureus, were constructed, and their antibacterial activities were analyzed. Objectives: This study analyzed the combined antibacterial effects of P-PNAs on S. aureus and S. pseudintermedius clinical isolates. Methods: S. aureus ATCC 29740 cells were treated simultaneously with serially diluted ASP-cmk and ASP-deoD, and the minimal inhibitory concentrations (MICs) were measured. The combined P-PNA mixture was then treated with S. aureus and S. pseudintermedius veterinary isolates at the determined MIC, and the antibacterial effect was examined. Results: The combined treatment of two P-PNAs showed higher antibacterial activity than the individual treatments. The MICs of two individual P-PNAs were 20 and 25 µM, whereas that of the combined treatment was 10 µM. The application of a combined treatment to clinical Staphylococcus spp. revealed S. aureus isolates to be resistant to P-PNAs and S. pseudintermedius isolates to be susceptible. Conclusions: These observations highlight the complexity of designing ASPs with high efficacy for potential applications in treating staphylococcal infections in humans and animals.

• Journal of the Korean Society of Radiology
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• v.81 no.5
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• pp.1204-1209
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• 2020

Cases of undifferentiated pleomorphic sarcoma of the thoracic aorta are rare, and usually present with embolic events, renovascular hypertension, or back pain. Mural-based undifferentiated pleomorphic sarcomas that present as ruptured saccular aneurysms are extremely rare and are difficult to differentiate from mycotic aneurysms or penetrating atherosclerotic ulcers. Herein, we report a case of histopathologically proven undifferentiated pleomorphic sarcoma arising from the wall of the descending thoracic aorta that manifested as a mass after thoracic endovascular aortic repair for the treatment of a ruptured saccular aneurysm. We present findings obtained by CT and PET to provide helpful information for the accurate diagnosis and appropriate treatment of future cases.

• Journal of the Korea Institute of Military Science and Technology
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• v.27 no.2
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• pp.222-229
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• 2024

As the operating condition for the penetrating missile has been more advanced, the survivability of main charge has been strongly required when the warhead impacts the target. Lots of efforts to desensitize explosives such as the development of insensitive molecular explosives or optimizing plastic-bonded explosives(PBX) systems has been made to enhance the survivability of main charge. However, these efforts face their limits as the weapon system require higher performance. Herein, we suggest a new strategy to secure the survivability of main charge. We applied structurally supportable aluminum honeycomb(HC) structure to cast PBX. The aluminum HC structure reinforces the mechanical strength of cast PBX and helps it to withstand external pressure without the reaction like detonation. In this study, impact resistance character, shock sensitivity and internal blast performance of PBXs reinforced with HC structure were investigated according to the application of aluminum HC structure. The newly suggested aluminum HC structure applied to cast PBX was proved to be a promising manufacturing method available for high-tech weapon systems.

• Journal of Trauma and Injury
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• v.37 no.1
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• pp.74-78
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• 2024

Inferior vena cava (IVC) injuries can have fatal outcomes and are associated with high mortality rates. Patients with IVC injuries require multiple procedures, including prehospital care, surgical techniques, and postoperative care. We present the case of a 67-year-old woman who stabbed herself in the abdomen with a knife, resulting in an infrarenal IVC injury. We shortened the transfer time by transporting the patient using a helicopter and decided to perform direct-to-operating room resuscitation by a trauma physician in the helicopter. The patient underwent laparotomy with IVC ligation for damage control during the first operation. The second- and third-look operations, including previous suture removal, IVC reconstruction, and IVC thrombectomy, were performed by a trauma surgeon specializing in cardiovascular diseases. The patient was discharged without major complications on the 19th postoperative day with rivaroxaban as an anticoagulant medication. Computed tomography angiography at the outpatient clinic showed that thrombi in the IVC and both iliac veins had been completely removed. Patients with IVC injuries can be effectively treated using a trauma system that includes fast transportation by helicopter, damage control for rapid hemostasis, and expert treatment of IVC injuries.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.44 no.3
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• pp.385-396
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• 2024

To enhance the accuracy of sinkhole detection using GPR, this study derived a convolutional neural network that can optimally extract sinkhole characteristics from GPR B-scan grayscale images. The pre-trained convolutional neural network is evaluated to be more than twice as effective as the vanilla convolutional neural network. In pre-trained convolutional neural networks, fast feature extraction is found to cause less overfitting than feature extraction. It is analyzed that the top-1 verification accuracy and computation time are different depending on the type of architecture and simulation conditions. Among the pre-trained convolutional neural networks, InceptionV3 are evaluated as most robust for sinkhole detection in GPR B-scan grayscale images. When considering both top-1 verification accuracy and architecture efficiency index, VGG19 and VGG16 are analyzed to have high efficiency as the backbone for extracting sinkhole feature from GPR B-scan grayscale images. MobileNetV3-Large backbone is found to be suitable when mounted on GPR equipment to extract sinkhole feature in real time.

• Journal of Trauma and Injury
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• v.37 no.3
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• pp.233-237
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• 2024

Bullet embolism is a potential complication of a gunshot wound, especially with a low-velocity missile. This is because the trajectory of the low-velocity bullet can be significantly slowed as it passes through tissue. An unusual form of travel can occur in which the bullet enters the vasculature but does not have enough kinetic energy to create a through-and-through wound, leading it to remain inside the vasculature. Once inside the vasculature, the bullet could migrate to different parts of the body, potentially causing complications such as ischemia, becoming a source of thromboembolism, or functioning as a nidus for infection. The management of a bullet embolism varies from case to case, as each patient with this issue has a unique body habitus that can result in infinite possibilities of the trajectory and destination of the bullet embolus. Additional damage to surrounding vasculature or tissue can occur, as well as embolization of the bullet to critical areas of the body. Here we present the case of a 72-year-old man who had a self-inflicted gunshot wound to the chest with a low-velocity bullet, which penetrated the right atrium of the heart. It traveled into the venous vasculature through the right atrium, into the inferior vena cava, and eventually settled in the right internal iliac vein. He refused further intervention and management after initial workup and resuscitation.

• Journal of Investigative Cosmetology
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• v.15 no.3
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• pp.263-273
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• 2019

The purpose of this study is to investigate antioxidant, whitening and anti-inflammatory effects of Centella asiatica extracts using supercritical extraction. In addition, Franz diffusion cell experiment was conducted using polymer micelle and cell permeation peptide for transdermal delivery. The DPPH radical scavenging test showed the highest DPPH radiated scavenging of C. asiatica water extract (CWE) and the SOD-like activity experiment represented that C. asiatica ethanol extract (CEE) was the highest SOD-like activity. However, C. asiatica supercritical extract (CSE) also showed good results in DPPH radical scavenging and SOD-like activity. In the inhibition test of melanin induced by α-MSH in B16 cells, CWE & CEE showed melanin inhibiting at high concentrations, but less than 20% at concentrations below 200 ㎍/mL. CSE represented melanin inhibiting at less than 50 ㎍/mL and almost 50% inhibition at the concentration. The inhibitory results of NO (nitric oxide) generation induced by LPS showed 88% by CWE at a concentration of 800 ㎍/mL compared to control treated only by LPS, 13% by CEE at a concentration of 200 ㎍/mL, 71% by CSE at a concentration of 100 ㎍/mL, and concentration-dependent increases in inhibits were found in CWE & CSE. For the skin permeability, in vitro experiment was conducted using polymer micelle and cell permeation peptide (R6) using the indicator material for CSE. The experiment showed that polymer micelle and cell permeation peptide effectively helped permeate the percutaneous tissue of CSE.

• Journal of Chest Surgery
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• v.40 no.12
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• pp.831-836
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• 2007

Background: Cardiac injuries are the most commonly overlooked injuries in patients who die from trauma. Patients who survive blunt cardiac rupture or penetrating injuries are rare and the incidence is not well defined. Many patients require urgent or emergency operations and operative mortality is very high. Material and Method: A retrospective review of 26 patients with cardiac injuries due to thoracic trauma undergoing emergency thoracotomy from January 1997 to December 2005. Result: There were 17 male and 9 female patients, with a mean age of $45.3{\pm}16.2\;(range:\;17{\sim}80)$. Thirteen patients (50%) were injured in motor vehicle accidents, and five patients (19%) in motorcycle accidents. Six patients (23%) were injured by knives, and two patients (8%) were injured by falling. Anatomic injuries included right atrium (12 [46%]), left atrium (1 [4%]), right ventricle (5 [19%]), left ventricle (5 [19%]), and cardiac chambers (2 [7%]). Diagnosis was made by computer tomography in 12 patients and sonography in 14 patients. The average times from admission to operating room was $89.2{\pm}86.7\;min\;(range:\;10{\sim}335)$. The average time for diagnosis was $51.3{\pm}13.6\;min\;(range:\;5{\sim}280)$. The mean Revised Trauma Score (RTS) was $6.7{\pm}0.8$, and the Glasgow Coma Scale (GCS), was $12.8{\pm}2.8$. The overall mortality rate was 12% (3 out of 26 patients). Conclusion: The mortality rate from cardiac injury is very high. The survival rate can be increased only by a high index of suspicion, aggressive expeditious diagnostic evaluation, and prompt appropriate surgical management.

• Journal of Chest Surgery
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• v.42 no.1
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• pp.46-52
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• 2009

Background: Vascular injuries to the extremities are potentially devastating and they can lead to limb loss and mortality if they are not appropriately managed. The vascular trauma caused by traffic and industrial accidents has recently increased according to the developing industry and transport system in Korea. Early recognition and treatment of these injuries are mandatory to achieve satisfactory outcomes. Material and Method: We retrospective reviewed 43 patients with vascular injuries that were due to blunt and penetrating trauma and they underwent emergency operations from January of 1998 to December of 2006. Result: There were 38 men and 5 women patients with a mean age of $42.0{\pm}16.8$ years (range: 17~77). The cause of vascular injuries were 28 traffic accidents (65%), 6 industrial accidents (14%), 6 glass injuries (14%) and 3 knife injuries (7%). The average time from admission to the operating room was $319.0{\pm}482.2$ minutes (range: 27~2,400 minutes). The average time from admission to discharge was $53.1{\pm}56.0$ days (range: 2~265 days). The anatomic injuries included the femoral artery in 16 cases (37%), the popliteal artery in 8 cases (19%), the brachial artery in 8 cases (19%), and the subclavian and axillary arteries in 7 cases (16%). The associated injuries were 23 bone fractures (53%), 18 muscle injuries (42%) 5 nerve injuries (12%) and 11 vein injuries (26%). The operation methods were 20 end to end anastomoses (46%), 16 interposition grafts (36%), 2 repairs with using patches (5%) and 5 others (12%). The number of amputations and cases of mortality were 3 cases (7%) and 4 cases (9%), respectively. Conclusion: Minimizing ischemia is an important factor for maximizing salvage of extremities. Prompt diagnosis and treatment can reduce the amputation and mortality rates.