• Geomechanics and Engineering
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• v.18 no.3
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• pp.225-234
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• 2019

A numerical stepwise approach for cavity expansion problem in strain-softening rock or soil mass is investigated, which is compatible with Mohr-Coulomb and generalized Hoek-Brown failure criteria. Based on finite difference method, plastic region is divided into a finite number of concentric rings whose thicknesses are determined internally to satisfy the equilibrium and compatibility equations, the material parameters of the rock or soil mass are assumed to be the same in each ring. For the strain-softening behavior, the strength parameters are assumed to be a linear function of deviatoric plastic strain (${\gamma}p^*$) for each ring. Increments of stress and strain for each ring are calculated with the finite difference method. Assumptions of large-strain for soil mass and small-strain for rock mass are adopted, respectively. A new numerical stepwise approach for limited pressure and plastic radius are obtained. Comparisons are conducted to validate the correctness of the proposed approach with Vesic's solution (1972). The results show that the perfectly elasto-plastic model may underestimate the displacement and stresses in cavity expansion than strain-softening coefficient considered. The results of limit expansion pressure based on the generalised H-B failure criterion are less than those obtained based on the M-C failure criterion.

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.341-349
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• 2018

The aim of this study was to evaluate autophagy-enhancing and neuroprotective effects of Wonji-Gobon mixture (WGM), a traditional Chinese prescription medication, in Parkinson's disease (PD) mouse models. Our investigation found that WGM increased the expression of both Beclin1 and LC3b-II proteins as measured with western blot in the BV2 cell line; both proteins play a role in autophagy. WGM also increased the autophagy expression as measured by fluorescence-activated cell-sorting analysis in the BV2 cell line. In 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced PD models, WGM significantly increased the amount of dopamine in a striatum-substantia nigra suspension, produced notable results in the forced swim test, and increased serotonin as measured by high-performance liquid chromatography analysis; these results are indicative of neuroprotective effects. In summary, our findings indicate that WGM treatment has neuroprotective effects that are partially mediated by autophagy enhancement.

• Journal of Korean Public Health Nursing
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• v.32 no.3
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• pp.388-399
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• 2018

Purpose: The aim of this qualitative study was to identify the experiences of smoking and smoking cessation in out-of-school youth. Methods: The participants were 12 out-of-school youths belonging the Youth support Center located in A and B area. The data were collected from January 8 to 15, 2018, using a FGI(Focus Group Interview). The main sub-domains of the experiences of smoking and smoking cessation in out-of-school youth by 7 questions were categorized from the intrapersonal, interpersonal, organizational, and community factors in ecological model. Results: The motivation, continuity, disadvantage of smoking experiences of out-of-school youth were analyzed in 10 sub-domains (curiosity, friend's invitation, mood of adapted group, habit, relieving stress, providing breaks, friendship, physical damage, loss of money, a bad sight of smoker). The reason, difficulty, advantage, reason for restarting smoking cessation experiences of out-of-school youth were analyzed in 15 sub-domains (physical damage, for future hope, invitation of others, influence of family, weight gain, emotional stress, worsening friendship, improvement physical condition, saving money, better relationships, not with bad friends, withdrawal, smoking of friends, drinking, separated a lover). Conclusion: Based on the results, it is expected that a Specialized Smoking Cessation Education Program will be developed for out-of-school youth's health activities in ecological factors.

• Current Optics and Photonics
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• v.3 no.1
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• pp.54-65
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• 2019

To develop a biomarker predicting tumor treatment efficacy is helpful to reduce time, medical expenditure, and efforts in oncology therapy. In clinics, microvessel density using immunohistochemistry has been proposed as an indicator that correlates with both tumor size and metastasis of cancer. In the preclinical study, we hypothesized that vascular morphometrics using optical coherence tomography angiography (OCTA) could be potential indicators to estimate the treatment efficacy of breast cancer. To verify this hypothesis, a 13762-MAT-B-III rat breast tumor was grown in a dorsal skinfold window chamber which was applied to a nude mouse, and the change in vascular morphology was longitudinally monitored during tumor growth and metronomic cyclophosphamide treatment. Based on the daily OCTA maximum intensity projection map, multiple vessel parameters (vessel skeleton density, vessel diameter index, fractal dimension, and lacunarity) were compared with the tumor size in no tumor, treated tumor, and untreated tumor cases. Although each case has only one animal, we found that the vessel skeleton density (VSD), vessel diameter index and fractal dimension (FD) tended to be positively correlated with tumor size while lacunarity showed a partially negative correlation. Moreover, we observed that the changes in the VSD and FD are prior to the morphological change of the tumor. This feasibility study would be helpful in evaluating the tumor vascular response to treatment in preclinical settings.

• Toxicological Research
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• v.35 no.4
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• pp.353-359
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• 2019

The purpose of this study was to investigate the effect of $7-MEGA^{TM}$ 500 on the improvement of skin aging in an UVB-induced photo-aging model of hairless mice. The dorsal skin of hairless mice was exposed to UVB three times a week for 12 weeks to induce skin wrinkle. After inducing the wrinkle, $7-MEGA^{TM}$ 500 was orally administered once a day for 4 weeks. Skin thickness, skin barrier function, and wrinkle indicators were improved by treatment with $7-MEGA^{TM}$ 500. Both gene and protein expression levels of MMP-3 and c-Jun in skin were significantly decreased by $7-MEGA^{TM}$ 500. Therefore, the intake of $7-MEGA^{TM}$ 500 is thought to have a positive effect on the improvement of skin aging, although further studies are needed.

• Bulletin of the Korean Chemical Society
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• v.11 no.3
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• pp.209-214
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• 1990

A series of compounds consisting of 4'-oxybenzylidene-4-n-butylaniline, a mesogen, and a p-substituted phenoxyterephthaloyl structure a non-mesogen, interconnected through a central hexamethylene spacer were synthesized and their thermal behavior and liquid crystallinity were studied. p-Substituents included in this study are H, Cl, CN, $NO_2,\;n-C_4H_9O$ and phenyl groups. The compounds having phenyl and $n-C_4H_9O$ substituents are enantiotropic and form smectic-A(SA) and nematic (N) phases. The compound with $NO_2$ substituent is monotropic and forms only a nematic phase on heating the solid, whereas it forms nematic as well as $S_A$ phases on cooling the isotropic liquid. The rest compounds were found to be non-liquid crystalline. This is in great contrast to the fact that the monomesogenic model compound 4'-n-hexyloxybenzylidine-4-n-butylaniline forms $S_B,\;S_C,\;S_A$ and N phases enantiotropically.

• Genomics & Informatics
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• v.19 no.4
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• pp.43.1-43.12
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• 2021

Campylobacter jejuni is one of the most prevalent organisms associated with foodborne illness across the globe causing campylobacteriosis and gastritis. Many proteins of C. jejuni are still unidentified. The purpose of this study was to determine the structure and function of a non-annotated hypothetical protein (HP) from C. jejuni. A number of properties like physiochemical characteristics, 3D structure, and functional annotation of the HP (accession No. CAG2129885.1) were predicted using various bioinformatics tools followed by further validation and quality assessment. Moreover, the protein-protein interactions and active site were obtained from the STRING and CASTp server, respectively. The hypothesized protein possesses various characteristics including an acidic pH, thermal stability, water solubility, and cytoplasmic distribution. While alpha-helix and random coil structures are the most prominent structural components of this protein, most of it is formed of helices and coils. Along with expected quality, the 3D model has been found to be novel. This study has identified the potential role of the HP in 2-methylcitric acid cycle and propionate catabolism. Furthermore, protein-protein interactions revealed several significant functional partners. The in-silico characterization of this protein will assist to understand its molecular mechanism of action better. The methodology of this study would also serve as the basis for additional research into proteomic and genomic data for functional potential identification.

• Wind and Structures
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• v.37 no.3
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• pp.245-254
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• 2023

In this paper, the wind-induced response of Jiayuguan wooden building (world cultural heritage) in Northwest China was studied. ANSYS finite element software was used to establish four kinds of building models under different working conditions and carry out modal analysis. The simulation results were compared with the field dynamic test results, obtaining the model which reflects the real vibration characteristics of the wooden tower. Time history data of fluctuating wind speed was obtained by MATLAB programming. Time domain method and ANSYS were used to analyze the wind-induced vibration response time history of Jiayuguan wooden building, obtaining the displacement time history curve of the structure. It was suggested that the wind-induced vibration coefficient of Jiayuguan wooden building is 1.76. Through analysis of the performance of the building under equivalent static wind load, the maximum displacement occurs in the three-story wall, gold column and the whole roof area, and the maximum displacement of the building is 5.39 cm. The ratio of the maximum stress value to the allowable value of wood tensile strength is 45 %. The research results can provide reference for the wind resistant design and protection of ancient buildings with similar structure to Jiayuguan wooden tower.

• Transactions of Materials Processing
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• v.33 no.3
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• pp.169-177
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• 2024

Recently, hydrogen energy has been widely used because of strict regulations on greenhouse gas emissions. For using the hydrogen energy, it is required to supply hydrogen through a tube trailer. However hydrogen tube trailer can have excessive load problems during transportation due to reasons such as road shape and driving method, which may lead a risk of hydrogen leakage. So it is necessary to secure a high level of safety. The purpose of this study is to evaluate structural safety for the conservative design of hydrogen tube trailer. First, finite element(FE) modeling of the designed hydrogen tube trailer was performed. After that, safety evaluation method was established through static structural simulation based on the standard GC207 conditions. In addition, effectiveness of the designed model was confirmed through the results of the structural safety evaluation. Finally, driving simulation was used to derive acceleration graph according to time, which was considered as a dynamic property for the evaluation of conservative tube trailer safety evaluation. And dynamic structural simulation was conducted as a condition for actual transportation of tube trailer by applying dynamic properties. As a results, conservative safety was evaluated through dynamic structural simulation and the safety of hydrogen tube trailer was confirmed through satisfaction of the safety rate.

• Journal of Engineering Education Research
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• v.27 no.3
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• pp.14-25
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• 2024

The purpose of this study was to conduct a needs analysis among experts regarding the curriculum in the field of new and renewable energy for the future experts. To achieve this goal, purposive sampling was employed to select 30 experts from the reginal, industrial, academic, and research sectors in the new and renewable energy field, who participated in needs surveys and expert Delphi surveys. Needs assessments for 53 courses and suitability evaluations for 6 curriculums were conducted, and comprehensive advisory opinions were gathered. Data were analyzed using t-tests, Brich's needs assessment, the locus for focus model, and content analysis methods, with the assistance of MS Office Excel 2018 and SPSS 25.0 software. The key findings include: (a) 18 courses should be given top priority for operation, while 4 courses should be considered secondarily; (b) All 6 curriculums received positive evaluations; (c) Improvements are needed in curriculum development to cater to both generalist and specialist training needs, incorporating the acquisition of new technology and project-based learning experiences. The results of this study provide implications for the development of customized curriculums in the new and renewable energy industry.