• Nuclear Engineering and Technology
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• v.55 no.1
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• pp.270-277
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• 2023

Exposure to ionizing radiation induces free radicals in human nails. These free radicals generate a radiation-induced signal (RIS) in electron paramagnetic resonance (EPR) spectroscopy. Compared with the RIS of tooth enamel samples, that in human nails is more affected by moisture and heat, but has the advantages of being sensitive to radiation and easy to collect. The fingernail as a biological sample is applicable in retrospective dosimetry in cases of localized hand exposure accidents. In this study, the dosimetric characteristics of fingernails were analyzed in fingernail clippings collected from Korean donors. The dose response, fading of radiation-induced and mechanically induced signals, treatment method for evaluation of background signal, minimum detectable dose, and minimum detectable mass were investigated to propose a fingernail-EPR dosimetry protocol. In addition, to validate the practicality of the protocol, blind and field experiments were performed in the laboratory and a non-destructive testing facility. The relative biases in the dose assessment result of the blind and field experiments were 8.43% and 21.68% on average between the reference and reconstructed doses. The results of this study suggest that fingernail-EPR dosimetry can be a useful method for the application of retrospective dosimetry in cases of radiological accidents.

• Structural Engineering and Mechanics
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• v.86 no.6
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• pp.705-714
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• 2023

In order to establish a dynamic model test method of bridge pylons subjected to ocean waves, the similarity method of hydroelastic model test for bridge pylons were analyzed systematically, and a model design and production method was proposed. Using this method, a dynamic test model of a bridge pylon was made, and then a free vibration test on the model structure and a dynamic response test of the model structure under wave actions were conducted in a wave flume. The results of the free vibration test show that the primary natural frequencies of the structure by the model test are close to the design frequencies of the prototype structure, indicating that the dynamic characteristics of the bridge pylon are well simulated by the model structure. The results of the dynamic response test show that wave induced base shear forces and motion responses on the model structure are consistent with the numerical results of the prototype structure. The model test results confirm that the proposed model test design method is feasible and applicable. It has application and reference significances for model testing studies of such marine bridge structures.

• Ocean Systems Engineering
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• v.13 no.3
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• pp.287-312
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• 2023

The global performance of a 15 MW floating offshore wind turbine, a newly designed semisubmersible floating foundation with multiple heave plates by CNOOC, is investigated with two independent turbine-floater-mooring coupled dynamic analysis programs CHARM3D-FAST and OrcaFlex. The semisubmersible platform hosts IEA 15 MW reference wind turbine modulated for VolturnUS-S and hybrid type (chain-wire-chain with clumps) 3×2 mooring lines targeting the water depth of 100 m. The numerical free-decay simulation results are compared with physical experiments with 1:64 scaled model in 3D wave basin, from which appropriate drag coefficients for heave plates were estimated. The tuned numerical simulation tools were then used for the feasibility and global performance analysis of the FOWT considering the 50-yr-storm condition and maximum operational condition. The effect of tower flexibility was investigated by comparing tower-base fore-aft bending moment and nacelle translational accelerations. It is found that the tower-base bending moment and nacelle accelerations can be appreciably increased due to the tower flexibility.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5747-5752
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• 2012

Purpose: The main objective of the present study was to evaluate the efficacy and toxicity of concurrent chemoradiotherapy followed by adjuvant chemotherapy compared with concurrent chemoradiotherapy alone in the treatment of locoregionally advanced nasopharyngeal carcinoma. Methods: The search strategy included Pubmed, Embase, the Cochrane Library, China National Knowledge Internet Web, Chinese Biomedical Database and Wanfang Database. We also searched reference lists of articles and the volumes of abstracts of scientific meetings. Randomized controlled trials (RCTs) that compared concurrent chemoradiotherapy followed by adjuvant chemotherapy with concurrent chemoradiotherapy alone in locoregionally advanced nasopharyngeal carcinoma were included. Meta-analysis was performed with RevMan 5.1.0. The Grading of Recommendations Assessment, Development, and Evaluation system (GRADE) was used to rate the level of evidence. Results: Five studies were included. Risk ratios of 1.02 (95%CI 0.89-1.15), 0.93 (95%CI 0.72-1.21), 1.07 (95%CI 0.87-1.32), 0.95 (95%CI 0.80-1.13) were observed for 3 years overall survival, 5 years failure-free survival, 5 years locoregional failure-free survival and 5 years distant metastasis failure-free survival. There were no treatment-related deaths in both groups of five studies. Hematologic and gastrointestinal toxicity were the most significant for patients during adjuvant chemotherapy. The level of evidence was low. Conclusion: Compared with concurrent chemoradiotherapy alone, concurrent chemotherapy followed by adjuvant chemotherapy did not improve prognosis. More toxicity was found during adjuvant chemotherapy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.7
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• pp.3207-3215
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• 2012

In this paper, we study the bending and free vibration analysis of nano plate, using a nonlocal elasticity theory of Eringen with a third-order shear deformation theory. This theory has ability to capture the both small scale effects and quadratic variation of shear strain and consequently shear stress through the plate thickness. Analytical solutions of bending and vibration of a laminated composite nano plate are presented using this theory to illustrate the effect of nonlocal theory on deflection of the nano plates. The relations between nonlocal third-order and local theories are discussed by numerical results. Further, effects of (i) nonlocal parameters, (ii) laminate schemes, (iii) directions of the fiber angle and (iv) number of layers on nondimensional deflections are investigated. In order to validate the present solutions, the reference solutions are used and discussed. The results of anisotropic nano plates using the nonlocal theory may be the benchmark test for the bending analysis.

• Archives of Plastic Surgery
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• v.42 no.6
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• pp.769-775
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• 2015

Background The radial forearm flap is a versatile, widely used flap. However, the possibility of donor site complications has led to concern over its use. Some surgeons prefer using other flaps whose donor sites can be closed primarily with less morbidity, including avoiding unpleasant scarring. However, in our experience, donor site stability of the radial forearm flap can be reliably achieved by using well-implemented specific procedures. Here, we present a collection of donor site cases of the radial forearm flap and investigate factors that affect the aesthetic results as the basis for a reference for selecting a radial forearm flap. Methods In this retrospective study, we reviewed 171 cases in which a radial forearm flap was used for free tissue transfer after resecting head and neck cancer. We focused on donor site morbidity rates. Each operation involved a detailed procedure designed to minimize donor site morbidity. Moreover, statistical investigations were conducted for 22 cases to determine factors affecting the scar appearance. Results Only one case developed total skin graft necrosis as a major complication. Scar-related aesthetic results were acceptable, and the body-mass index, body weight, diabetes, and cardiac problems were significant factors related to the appearance of scars. Conclusions Performing the radial forearm flap using a well-implemented detailed technique helps achieve acceptable donor site morbidity results. The aesthetic results were more promising for patients without excess body weight, diabetes, or cardiac problems. Therefore, anxiety about donor site morbidity should not be a reason to avoid selecting the radial forearm flap in suitable patients.

• CELLMED
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• v.6 no.2
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• pp.11.1-11.7
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• 2016

The aimed of the presence study was to determine the antiulcer potential of virgin coconut oil (VCO), either extracted by wet process (VCO_A) or fermentation process (VCO_B), and to compare their effectiveness against the copra oil (CO) using the HCl/ethanol-induced gastric ulcer model. Earlier, the oils underwent chemical analysis to determine the free fatty acids composition, physicochemical properties and anti-oxidant capability. In the antiulcer study, rats (n=6) were pre-treated orally for 7 consecutive days with distilled water (vehicle), 100 mg/kg ranitidine (positive group) or the respective oils (10, 50, and 100% concentration). One hour after the last test solutions administration on Day 7^th, the animals were subjected to the gastric ulcer assay. Macroscopic and microscopic analyses were performed on the collected rat's stomachs. From the results obtained, the chemical analysis revealed i) the presence of high content of lauric acid followed by myristic acid and palmitic acid in all oils and; ii) the significant (^*p< 0.05) different in anisidine- and peroxide-value, percentage of free fatty acid, total phenolic content and total antioxidant activity among the oils. The animal study demonstrated that all oil possess significant (^*p< 0.05) antiulcer activity with VCO_B being the most effective oil followed by VCO_A and CO. The macroscopic observations were supported by the microscopic findings. Interestingly, all oils were more effective than 100 mg/kg ranitidine (reference drug). In conclusion, coconut oils exert remarkable antiulcer activity depending on their methods of extraction, possibly via the modulation of its antioxidant and anti-inflammatory activity.

• The Journal of Korean Medicine
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• v.28 no.1 s.69
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• pp.137-147
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• 2007

Objective : The objective of this study was to investigate the antioxidative effects of Carthami Flos extract. Methods : Total antioxidant status was examined by total antioxidant capacity(TAC) and total antioxidant response(TAR) against potent free radical reactions. The effect of Carthami Flos extract was examined far details of total phenolic content concentration at which 1,1-dipheny1-2-picrylhydrazyl(DPPH) radical scavenging activity was inhibited, the inhibitory effect on lipid peroxidation, and the effect on reactive oxygen species(ROS) generation. Results : TAC of Carthami Flos extract at the concentration of 5 mg/ml was 1.84 mM Trolox equivalent. 2. TAR of Carthami Flos extract, on the other hand, couldn't be determined due to interference from unidentified compounds. 3. Total phenolic content of Carthami Flos extract at the concentration of 5 mg/ml was 2.01 mM gallic acid equivalent. 4. Concentration of Carthami Flos extract at which DPPH radical scavenging activity was inhibited by 50% was 6.43 mg/ml as compared to 100% by Pyrogallol solution as a reference. 5. The inhibitory effect of the extract on lipid peroxidation was examined using rat liver mitochondria induced by FeS04/ascorbic acid. Carthami Flos extract at the concentration of 10 ms/ml slightly but significantly decreased TBARS concentration. The extract continued to prevent lipid peroxidation in a dose-dependent manner. 6. The effect of Carthami Flos extract on reactive oxygen species(ROS) generation was examined using a cell-free system induced by hydrogen peroxide/FeS04. Addition of 1 mg/ml of Carthami Flos extract significantly reduced dichlorofluorescein(DCF) fluorescence. Carthami Flos extract caused concentration-dependent attenuation of the increase in DCF fluorescence, indicating that the ektract significantly prevented ROS generation in vitro. Conclusion: : Antioxidant efffcts of Carffami ffor extract seem to be due, at least in part, to the prevention offree radical-induced oxidation, fellowed by inhibition of lipid peroxidation.

• The Journal of Korean Medicine
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• v.28 no.1 s.69
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• pp.148-158
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• 2007

Objective : The objective of this study was to investigate the antioxidant effects of Mori Folium extract. Methods Total antioxidant status was examined by total antioxidant capacity(TAC) and total antioxidant response(TAR) against potent free radical reactions. The effect of Mori Folium extract was examined by measuring total phenolic content, concentration at which 1,1-dipheny1-2-picrylhydrazyl(DPPH) radical scavenging activity was inhibited, inhibitory effect on lipid peroxidation, and the effect on reactive oxygen species(ROS) generation. Results : 1. TAC and TAR of Mori Folium extract at the concentration of 5 mg/ml were 1.61 and 1.24 mM Trolox equivalents, respectively. 2. Total phenolic content of Mori Folium extract at the concentration of 5 mg/Ml was 1.70 mM gallic acid equivalent. 3. Concentration of Mori Folium extract at which DPPH radical scavenging activity was inhibited by 50% was 2.29 m9/m4 as compared to 100% by Pyrogallol solution as a reference. 4. The inhibitory effect of the extract on lipid peroxidation was examined using rat liver mitochondria induced by FeSO$_4$/ascorbic acid. Mori Folium extract at the concentration of 10 mg/ml significantly decreased thiobarbituric acid reactive substances(TBARS) concentration. The extract prevented lipid peroxidation in a dose-dependent 5. The effect of Mori Folium extract on reactive oxygen species(ROS) generation was examined using a celt-free system induced by hydrogen peroxide FeSO$_4$. Addition of 1 mg/ml of Mori Folium extract significantly reduced dichlorofluorescein(DCf) fluorescence. The extract caused concentration-dependent attenuation of the increase in DCF fluorescence, indicating that the extract significantly prevented ROS generation in vitro. Conclusion ; The antioxidant effects of Mori Folium extract seem to be due, at least in part, to the prevention offree radical-induced oxidation, fllowed by inhibition of lipid peroxidation.

• Journal of Pharmacopuncture
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• v.10 no.2 s.23
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• pp.57-65
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• 2007

Objectives : The purpose of this study was to investigate the antioxidative effects of Ephedrae Herba extract. Methods : Total antioxidant status was examined by total antioxidant capacity(TAC), total antioxidant response(TAR) against potent free radical reactions, total phenolic content, DPPH radical scavenging activities, and the inhibitory effect of the extract on lipid peroxidation in rat liver mitochondria. Results : 1. TAC and TAR of Ephedrae Herba extract at the concentration of 5mg/ml were 3.76 and 1.65 mM Trolox equivalents , respectively. 2. Total phenolic content of Ephedrae Herba extract at the concenuation of 5mg/ml was 3.52 mM gallic acid equivalent. 3. Concentration of Ephedrae Herba extract at which DPPH radical scavenging activity was inhibited by 50% was 0.46mg/ml as compared to 100% by pyrogallol solution as a reference. 4. Ephedrae Herba extract at the concentration of 2mg/ml significantly decreased TBARS concentration by 97%, showing that Ephedrae Herba extract prevented lipid peroxidation at the low concentration. Conclusion : Thus antioxidant effects of Ephedrae Herba extract appear to be due to, at least in part, the prevention from free radicalsinduced oxidation, followed by inhibition of lipid peroxidation.