• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.2335-2347
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• 2023

As medical facilities are usually built at urban areas, special concrete aggregates and evaluation methods are needed to optimize the design of concrete walls by balancing density, thickness, material composition, cost, and other factors. Carbon treatment rooms require a high radiation shielding requirement, as the neutron yield from carbon therapy is much higher than the neutron yield of protons. In this case study, the maximum carbon energy is 430 MeV/u and the maximum current is 0.27 nA from a hybrid particle therapy system. Hospital or facility construction should consider this requirement to design a special heavy concrete. In this work, magnetite is adopted as the major aggregate. Density is determined mainly by the major aggregate content of magnetite, and a heavy concrete test block was constructed for structural tests. The compressive strength is 35.7 MPa. The density ranges from 3.65 g/cm³ to 4.14 g/cm³, and the iron mass content ranges from 53.78% to 60.38% from the 12 cored sample measurements. It was found that there is a linear relationship between density and iron content, and mixing impurities should be the major reason leading to the nonuniform element and density distribution. The effect of this nonuniformity on radiation shielding properties for a carbon treatment room is investigated by three groups of Monte Carlo simulations. Higher density dominates to reduce shielding thickness. However, a higher content of high-Z elements will weaken the shielding strength, especially at a lower dose rate threshold and vice versa. The weakened side effect of a high iron content on the shielding property is obvious at 2.5 µSv=h. Therefore, we should not blindly pursue high Z content in engineering. If the thickness is constrained to 2 m, then the density can be reduced to 3.3 g/cm³, which will save cost by reducing the magnetite composition with 50.44% iron content. If a higher density of 3.9 g/cm³ with 57.65% iron content is selected for construction, then the thickness of the wall can be reduced to 174.2 cm, which will save space for equipment installation.

• The Korean Journal of Pain
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• v.31 no.1
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• pp.3-9
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• 2018

Long QT syndrome is a cardiac repolarization disorder and is associated with an increased risk of torsades de pointes. The acquired form is most often attributable to administration of specific medications and/or electrolyte imbalance. This review provides insights into the risk for QT prolongation associated with drugs frequently used in the treatment of chronic pain. In the field of pain medicine all the major drug classes (i.e. NSAIDs, opioids, anticonvulsive and antidepressant drugs, cannabinoids, muscle relaxants) contain agents that increase the risk of QT prolongation. Other substances, not used in the treatment of pain, such as proton pump inhibitors, antiemetics, and diuretics are also associated with long QT syndrome. When the possible benefits of therapy outweigh the associated risks, slow dose titration and electrocardiography monitoring are recommended.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2006.08a
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• pp.119-119
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• 2006

• Proceedings of the Korean Society of Medical Physics Conference
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• 2006.08a
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• pp.81-81
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• 2006

• Proceedings of the Korean Society of Medical Physics Conference
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• 2006.08a
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• pp.57-57
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• 2006

• Proceedings of the Korean Society of Medical Physics Conference
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• 2006.08a
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• pp.86-86
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• 2006

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.18 no.2
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• pp.102-107
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• 2007

Laryngopharyngeal reflux disease (LPRD) is the result of retrograde flow of gastric contents to the laryngopharynx. Laryngoscopic findings and special questionnaires are first step of diagnosis of LPRD. Empiric trials of Proton pump inhibitor' test (PPI test) is recommended as treatment and diagnosis. However confirmation of reflux is then recommended primarily in patients with persistent symptoms despite acid-suppressive therapy. The 24 hour ambulatory double pH monitoring has been a gold standard method in diagnosis of LPRD even though it has some limitation. The combined multichannel intraluminal impedance and pH monitoring is a new-rising test tool. It can detect acid/non-acid, liquid/gaseous reflux and clearance of refluxate. The water siphon test is also used for diagnosis of LPRD.

• Archives of Pharmacal Research
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• v.24 no.6
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• pp.485-498
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• 2001

Helicobacter pylori is one of the most commonly encountered human pathogens. It has been shown to be closely associated with peptic ulcer disease (PUD), gastric adenocarcinoma, and the gastric mucosa-associated lymphoid tissue (MALT) that may lead to gastric lymphoma. The current diagnostic methods include histology, microbiological culture, classic serology unease activity detection, polymerase chain reaction (PCR) and stool antigen detection. Its treatment modality options are multiple; however, a triple regimen consisting of a proton pump inhibitor (PPI), and two antibiotics for 10 to 14 days is preferred. Drug resistance is a growing problem in this organism and new therapeutic options are currently limited .

• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.1494-1497
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• 2007

양성자가속기는 재료산업, 반도체산업, 생명산업, 등 다양한 산업에 폭 넓게 이용되고 있다. 양성자가속기의 이용 분야에서 양성자 요법도 빼놓을 수 없는 중요한 분야이다. 양성자가속기의 제어 소프트웨어는 일반적으로 EPICS라는 개발 도구를 이용하여 개발하는데 반하여 양성자 요법에서는 제어시스템으로 IBA에서 개발된 PTS(Proton Therapy System)이 사용된다. 대형 양성자 가속기는 산업용과 의료용으로 다양하게 사용될 수 있으므로 EPICS로 개발된 제어소프트웨어와 IBA의 PTS가 호환성이 있든지 아니면 의료용의 양성자 요법 시스템용 제어소프트웨어까지 EPICS로 개발할 필요가 있다. 본 논문은 EPICS로 양성자 요법 시스템의 제어소프트웨어의 사용자 인터페이스를 구현한 결과를 소개한다.

• Journal of the Korean Society of Radiology
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• v.8 no.6
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• pp.325-332
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• 2014

Metallic nanoparticles have attractive properties in biomedical applications such as diagnostics and therapeutics. Cross linked dextran coated iron oxide nanoparticles (SPIONs) and silica coated gadolinium oxide nanoparticles (SPGONs) have been synthesized as a radiosensitizer in the proton beam cancer therapy. The dextran and silicaused for the protective moieties on the SPIONs and SPGONs respectively. Size distributions of synthesized nanoparticles were confirmed 3~5 nm for SPIONs and 30~100 nm for SPGONs by transmission electron microscope (TEM). Cell survival fraction measurement and Western blot assay were performed to evaluate the radiosensitization effects of synthesized radiosensitizer. The calculated radiosensitization of SPIONs and SPGONs at 90 % cell death from the measured cell survival curves were 1.23 and 1.03 respectively. Western blotting results also show the same consistent results that the amount of released cytochrome c from mitochondria was considerably increased for the cancer cells taken up SPIONs.