• Science & Technology Policy
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• v.16 no.3 s.159
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• pp.40-46
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• 2006

• Structural Engineering and Mechanics
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• v.72 no.5
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• pp.653-673
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• 2019

This work investigates a novel quasi-3D hyperbolic shear deformation theory is presented to discuss the buckling of new type of sandwich plates. This theory accounts for both shear deformation and thickness stretching effects by a hyperbolic variation of all displacements through the thickness. The enhancement of this formulation is due to the use of only five unknowns by including undetermined integral terms, contrary to other theories where we find six or more unknowns. It does not require shear correction factors and transverse shear stresses vary parabolically across the thickness. A new type of FGM sandwich plates, namely, both FGM face sheets and FGM hard core are considered. The governing equations and boundary conditions are derived using the principle of virtual displacements. Analytical solutions are obtained for a simply supported plate. The accuracy of the present theory is verified by comparing the obtained results with quasi-3D solutions and those predicted by higher-order shear deformation theories. The comparison studies show that the obtained results are not only more accurate than those obtained by higher-order shear deformation theories, but also comparable with those predicted by quasi-3D theories with a greater number of unknowns.

• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2835-2840
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• 2010

A series of $MoO_3/CeO_2-ZrO_2$ catalysts with different Mo content (8 - 20 wt %) were prepared by simple co-precipitation followed by impregnation method and were characterized by X-ray diffraction (XRD), infrared spectroscopy (IR), scanning electron microscopy (SEM), energy dispersive spectroscopic (EDS) techniques. The prepared materials were tested for catalytic activity by the synthesis of benzimidazole derivatives using condensation of aromatic aldehydes and o-phenylenediamine by conventional and microwave method. Obtained results reveal that the catalytic activity increases with increase in Mo wt % loading. The best catalytic activity was obtained with 20 wt % $MoO_3/CeO_2-ZrO_2$. The particle size or crystallite size was estimated using Debye-Scherrer equation. After completion of reaction, the catalyst can be recovered efficiently and reused with consistent activity.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.3
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• pp.107-114
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• 2022

Carboxymethyl cellulose/poly(ethylene glycol) (CMC/PEG) hydrogels crosslinked with citric acid (CA) are synthesized to evaluate the effect of CMC molecular weight (Mw), PEG and CA concentration on the optical property, swelling rate (SR), degradation rate (DR), and cytotoxicity and cell proliferation of hydrogels. For crosslinked CMC/PEG hydrogels, the FT-IR peak intensity associated with hydroxyl groups decreases due to PEG intercalation (esterification crosslinking) between CMC chains in a similar manner as the concentration of CA crosslinker increases. Crosslinked CMC (Mw = 90,000)/PEG hydrogels with 10 % CA dissolve regardless of PEG content. However, the SR of the CMC (Mw = 250,000)/PEG hydrogels decrease from 4923 % to 168 % with increasing PEG and CA concentrations from 0 to 20 % and from 0 to 25 %, respectively. As the Mw of CMC increases, the DR of the hydrogel is greatly improved. CMC (Mw = 250,000)/PEG10 hydrogels with 10 % CA exhibit the optimum properties of high absorbing capacity (3,200 %) with moderate DR (54 %), stiffness (1.39 ± 0.19 GPa), and cell viability (94.8 ± 1.3 %). CA-crosslinked CMC/PEG hydrogels are highly suitable for wound dressing or personal care applications due to their non-toxicity, good cell proliferation, SR, and mechanical properties.

• Nutrition Research and Practice
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• v.12 no.5
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• pp.406-414
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• 2018

BACKGROUND/OBJECTIVES: The objective of this study was to determine dysphagia risk among community-dwelling elderly people living at home. We also examined the impact of socio-demographic variables on dysphagia risk as well as the relationship between dysphagia risk and dietary characteristics. SUBJECTS/METHODS: The study sample included 568 community-dwelling individuals, aged 65 years and above, who were living independently in their own home in Seoul, Gyeonggi, or Gwangju in South Korea. We used a dysphagia risk assessment scale to screen for dysphagia risk and the Mini nutritional assessment to evaluate the nutritional status. Associations between dysphagia risk and other variables were assessed using logistic regression analysis. RESULTS: Of the 568 subjects, 350 (61.6%) were classified into the dysphagia risk group (DR) and 218 (38.4%) were classified into the normal group (non-DR). Being female (odds ratio (OR) = 1.82, 95% confidence interval (CI) = 1.28-2.59), being 75 years and older (OR = 2.40, 95% CI = 1.69-3.42), having a lower education level (OR = 2.29, 95% CI = 1.33-3.97), and having a lower perceived economic status (OR = 2.18, 95% CI = 1.32-3.60) were more frequently observed with dysphagia risk compared to those who did not have such characteristics. Lowered mastication ability (OR = 14.40, 95% CI = 4.43-46.95), being at risk of malnutrition or malnourished (OR = 2.72, 95% CI = 1.75-4.23), lowered appetite (OR = 3.27, 95% CI = 2.16-4.93), and decreased food intake (OR = 2.95, 95% CI = 1.83-4.78) were observed more frequently in the DR group than in the non-DR group when adjusting for potential confounding factors. CONCLUSIONS: It is necessary to develop and apply integrated programs to improve the dietary habits and nutritional status of elderly individuals at risk for dysphagia, especially for women aged 75 years or older with lower educational and economic levels.

• Journal of Digital Convergence
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• v.17 no.8
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• pp.257-264
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• 2019

This study was conducted to investigate the effect of 70% ethanol extract (DR) on the mast cell-mediated allergic contact dermatitis induced by dinitrofluorobenzene in BALB / c mice, which affects the cell activity by antigen in RBL-2H3 mast cells Respectively. The ethanol extracts of RBL-2H3 cells activated by DNP-HSA and anti-DNP IgE antibodies inhibited the secretion of ${\beta}$-hexosaminidase, histamine, and IL-4 and $TNF-{\alpha}$ Production was suppressed. In the DNFB-induced contact allergic dermatitis animal model, treatment with ethanol extract reduced ear swelling and inhibited serum histamine and IL-4 secretion, and DR treatment effectively prevented mast cell infiltration in dermatitis-induced areas. As a result, the ethanol extract may be used as a therapeutic agent for mast cell-mediated allergic diseases such as atopic dermatitis.

• Progress in Medical Physics
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• v.19 no.4
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• pp.298-304
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• 2008

Current digital radiographic systems are rapidly growing in clinical applications. The purpose of this study was to evaluate the diagnostic performance of computed radiography (CR) and digital radiography (DR) at different tube voltages in the detection of simulated chest lesions. Patterns of simulated interstitial lung disease, incipient infiltration, and nodules were superimposed over an anthropomorphic chest phantom. A simulated chest phantom radiograph was obtained with CR and DR at different tube voltages (70 kV, 90 kV, and 120 kV). A total of 18,000 observations were analyzed using a receiver operating characteristic (ROC) analysis. The detection of all lesions showed higher $A_z$ values at 70 kV than 120 kV with CR. For the DR, mean $A_z$ values at 70 kV were higher than other tube voltages not all lesions but for micro-nodule interstitial lung disease, linear interstitial lung disease, and incipient infiltration. Based on these results, a clinical study should be performed to judge the use of suitable tube voltage according to the type of detector system and lesions.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.489-494
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• 2013

Background: Lung cancer is one of the commonest and most lethal cancers throughout the world. The epidemiological and pathological profile varies among different ethnicities and geographical regions. At present adenocarcinoma is the commonest histological subtype of non-small cell lung cancer (NSCLC) in most of the Western and Asian countries. However, in India squamous cell carcinoma has been reported as the commonest histological type in most of the series. The aim of the study was to analyze the current clinico-pathological profile and survival of lung cancer at our centre. Materials and Methods: We analyzed 434 pathologically confirmed lung cancer cases registered at our centre over a period of three years. They were evaluated for their clinical and pathological profiles, treatment received and outcome. The available histology slides were reviewed by an independent reviewer. Results: Median age was 55 years with a male:female ratio of 4.6:1. Some 68% of patients were smokers. There were 85.3% NSCLC and 14.7% SCLC cases. Among NSCLCs, adenocarcinoma was the commonest histological subtype after the pathology review. Among NSCLC, 56.8% cases were of stage IV while among SCLC 71.8% cases had extensive stage disease. Some 29% of patients did not receive any anticancer treatment. The median overall and progression free survivals of the patients who received treatment were 12.8 and 7.8 months for NSCLC and 9.1 and 6.8 months for SCLC. Conclusions: This analysis suggests that adenocarcinoma may now be the commonest histological subtype also in India, provided a careful pathological review is done. Most of the patients present at advanced stage and outcome remains poor.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.964-970
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• 1999

Fatty acid composition and sensory characteristics of six commercial chickens(CC-RcDR, RcLR, BcBR, BcDR, BcLR, RcBR), one broiler(Arbor Acre) and three Korean native chickens(KNC-D, L, B) were evaluated. In the fatty acid composition at marketing age, KNC had generally higher unsaturated fatty acid ratio than the others. B, BcBR and BcDR showed the highest in unsaturated fatty acid but the lower than others in saturated fatty acid composition. The results of sensory test showed significant difference(P<0.05) only in the leg. B and RcBR had the highest score and Arbor Acre lowest score in juiciness. In tenderness. B had the highest score and RcDR lowest score. In the case of acceptability, KNC generally had high score. Particularly B had the highest score. Among CC, RcBR had the highest score. There were no significant differences in flavor and aroma.

• Carbon letters
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• v.3 no.4
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• pp.192-197
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• 2002

Microstructure plays an important role in controlling the fracture behaviour of carbon-carbon composites and hence their mechanical properties. In the present study effort was made to understand how the different interfaces (fiber/matrix interactions) influence the development of microstructure of the matrix as well as that of carbon fibers as the heat treatment temperature of the carbon-carbon composites is raised. Three different grades of PAN based carbon fibres were selected to offer different surface characteristics. It is observed that in case of high-strength carbon fiber based carbon-carbon composites, not only the matrix microstructure is different but the texture of carbon fiber changes from isotropic to anisotropic after HTT to $2600^{\circ}C$. However, in case of intermediate and high modulus carbon fiber based carbon-carbon composites, the carbon fiber texture remains nearly isotropic at $2600^{\circ}C$ because of relatively weak fiber-matrix interactions.