• The Korean Journal of Physiology and Pharmacology
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• v.22 no.5
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• pp.467-479
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• 2018

The aging process induces a plethora of changes in the body including alterations in hormonal regulation and metabolism in various organs including the heart. Aging is associated with marked increase in the vulnerability of the heart to ischemia-reperfusion injury. Furthermore, it significantly hampers the development of adaptive response to various forms of conditioning stimuli (pre/post/remote conditioning). Aging significantly impairs the activation of signaling pathways that mediate preconditioning-induced cardioprotection. It possibly impairs the uptake and release of adenosine, decreases the number of adenosine transporter sites and down-regulates the transcription of adenosine receptors in the myocardium to attenuate adenosine-mediated cardioprotection. Furthermore, aging decreases the expression of peroxisome proliferator-activated receptor gamma co-activator 1-alpha ($PGC-1{\alpha}$) and subsequent transcription of catalase enzyme which subsequently increases the oxidative stress and decreases the responsiveness to preconditioning stimuli in the senescent diabetic hearts. In addition, in the aged rat hearts, the conditioning stimulus fails to phosphorylate Akt kinase that is required for mediating cardioprotective signaling in the heart. Moreover, aging increases the concentration of $Na^+$ and $K^+$, connexin expression and caveolin abundance in the myocardium and increases the susceptibility to ischemia-reperfusion injury. In addition, aging also reduces the responsiveness to conditioning stimuli possibly due to reduced kinase signaling and reduced STAT-3 phosphorylation. However, aging is associated with an increase in MKP-1 phosphorylation, which dephosphorylates (deactivates) mitogen activated protein kinase that is involved in cardioprotective signaling. The present review describes aging as one of the major confounding factors in attenuating remote ischemic preconditioning-induced cardioprotection along with the possible mechanisms.

• Korean journal of food and cookery science
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• v.24 no.5
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• pp.626-635
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• 2008

The purpose principal objective of this study was to develop a muffin with the addition of jinuni bean powder. The whole Our analysis was conducted by using using Design Expert 7(Stat - Easy Co. Minneapolis). The jinuni bean muffin was produced by varying the contents of jinuni bean powder(A), sugar(B), and butter(C). According to the Response Surface Methodology(RSM), it showed we delineated 16 experimental points, including two replicants. The optimization We attempted to optimize of the jinuni bean muffins was studied with regard to its analysis of rheology and sensory evaluations. As a result of the redness, hardness, and sensory evaluations, characteristics such as color, appearance, flavor, softness, and overall quality showed a varied in accordance with a quadratic model, whereas lightness, yellowness, and cohesiveness, and gumminess showed evidenced a linear model pattern. Lightness, and yellowness decreased with the increases in the of jinuni bean powder content(p<0.0001), while whereas redness increased with the increases of in the content of jinuni bean powder(p<0.001), in case of over 80g, the redness tended to increase decrease again. In addition, hardness(p<0.05), gumminess(p<0.05), and cohesiveness(p<0.01) showed differed significantly differences with the increases of in the jinuni bean powder content. The results of our sensory evaluation results showed demonstrated significant values in color, appearance, flavor, softness,and overall quality values(p<0.05). The optimal formulation, as assessed by numerical and graphical methods, were was determined to be 50.05 g of jinuni bean powder, 78.56 g of sugar, and 90.97 g of butter.

• The Korean Journal of Food And Nutrition
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• v.27 no.6
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• pp.1132-1140
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• 2014

This study aimed to investigate the changes in antioxidant activities, quality characteristics, and storage stability of mayonnaise prepared with perilla oil with the addition of mulberry powder ranging from 0 to 5%. The antioxidant activities of perilla oil mayonnaise (PM), as determined by DPPH and ABTS radical scavenging activity, as well as FRAP and total phenolics content were improved by the addition of mulberry powder compared with the control sample. Antioxidant activities were dependent on the amount of mulberry powder added. Lipid oxidation of PM decreased with a higher amount of mulberry powder, based on measurements of peroxide value. The emulsion stability of PM increased with decreases in the amount of mulberry powder level. The a-value in PM color increased with increasing amount of mulberry powder. Sensory evaluation showed that the highest score in overall acceptability of PM was achieved with 4% mulberry.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.733-737
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• 2003

To develop a high-valuable Korean traditional rice wine having antihypertension, effects of some cereal kojis and legumes on alcohol fermentation and angiotensin I-converting enzyme (ACE) inhibitory activity of Korean traditional rice wine were investigated. Korean traditional rice wine brewed by addition of 10% Indian-millet koji into the mash showed the greatest ACE inhibitory activity of 43.0% and good ethanol productivity. The ACE inhibitory activity increased up to 69.2% by addition of 50% of mungbean powder and 1% of dandelion petal into the mash.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.189-189
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• 2008

Due to the environmental issue vast research is going on to replace the widely used lead contented piezoelectric materials. Bismuth sodium titanate (abbreviated as BNT) based bismuth sodium titanate-barium titanate (abbreviated as BNBT) ceramic was prepared by using modified method rather than conventional mixed oxide method. This modification was made to improve the properties of BNT based ceramic. In this procedure $BaTiO_3$ (abbreviated as BT) was prepared using conventional mixed oxide method. Analytical grade raw materials of $BaCO_3$ and $TiO_2$ were weighted and ball milled using ethanol medium. The mixed slurry was dried and sieved under 80 mesh. Then the powder was calcined at $1100^{\circ}C$ for 2 hours. This calcined BT powder was used in the preparation of BNBT. Stoichiometric amount of $Bi_2O_3$, $Na_2CO_3$, $TiO_2$ and BT were weighted and mixed by using ball mill. The used calcination temperature was $850^{\circ}C$ for 2 hours. Calcined powder was taken for another milling step. BNBT disks were pressed to 15 mm of diameter and then cold isostatical press (CIP) was used. Pressed samples were sintered at $1150^{\circ}C$ for 2 hours. The SEM microstructure analysis revealed that the grain shape of the sintered ceramic was polyhedral and grain boundary was well matched where as the sample prepared by conventional method showed irregular arrangement and grain boundary not well matched. And sintered density was better (5.78 g/cc) for the modified method. It was strongly observed that the properties of BNBT ceramic near MPB composition was found to be improved by the modified method compare to the conventional mixed oxide method. The piezoelectric constant dB of 177.33 pC/N, electromechanical coupling factor $k_p$ of 33.4%, dielectric constant $K_{33}^T$ of 688.237 and mechanical quality factor $Q_m$ of 109.37 was found.

• Journal of the Korean Chemical Society
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• v.61 no.6
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• pp.352-358
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• 2017

The addition of alginic acid, a natural polysaccharide, to improve the wettability and the reduction of protein adsorption of hydrogel contact lenses. Hydrogel contact lenses were manufactured with various monomers such as 2-methacryloyloxyethyl phosphorylcholine (MPC) and NVP (N-Vinyl-2-pyrrolidone). Alginic acid was added by by the initial mixing method and the interpenetrating polymer networks(IPN) method. Properties of contact lens such as contact angle, oxygen permeability, and protein adsorption amount were evaluated. The oxygen permeability and wettability of the IPN-treated alginate samples were higher than those of the samples that were not treated with IPN. The physical properties were improved as the concentration of IPN-treated alginic acid increased. Protein adsorption decreased by the addition of alginic acid and further decreased with IPN. In particular, contact lenses containing MPC and NVP significantly decreased protein adsorption. Therefore, the effect of alginate on the functional improvement of contact lens was confirmed.

• Journal of Sensor Science and Technology
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• v.29 no.6
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• pp.388-393
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• 2020

In this study, a PbS quantum dots (QDs)-based H₂ gas sensor with a Pd electrode was proposed. QDs have a size of several nanometers, and they can exhibit a high surface area when forming a thin film. In particular, the NH₂ present in the ligand of PbS QDs and H₂ gas are combined to form NH₃⁺, subsequently the electrical characteristics of the QDs change. In addition to the resistance change owing to the reaction between Pd and H₂ gas, the resistance change owing to the reaction between the NH₂ of PbS QDs and H₂ gas increases the current signal at the sensor output, which can produce a high output signal for the same concentration of H₂ gas. Using the XRD and absorbance properties, the synthesis and particle size of the synthesized PbS QDs were analyzed. Using PbS QDs, the sensitivity was significantly improved by 44%. In addition, the proposed H₂ gas sensor has high selectivity because it has low reactivity with heterogeneous gases such as C₂H₂, CO₂, and CH₄.

• Food Science and Preservation
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• v.8 no.1
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• pp.66-73
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• 2001

This study was carried out to know whether $\beta$-galactosidase is directly important or not on fruit softening during the development of peach fruits compared to those in the stage stage. It was investigated that the flesh firmness, cell wall components, and the glycosidase activities of the peach fruits with a fast softening cultivar, 'Mibeakdo', a slow softening cultivar,'Yumyung'and a middle softening cultivar, 'Okubo$\beta$, at different developmental stages, on 13 May, 16 June, 16 July, and 5 August and on 28 August which harvested only 'Yumyung' fruits. In order to investigate the amounts of total sugar and non-cellulosic neutral sugar, the cell wall materials of each fruit were solubilized in distilled water, 0.05M CDTA, 0.05M Na$_2$CO$_3$, 4% KOH, and 24% KOH sequentially. During the fruit development, the fruit firmness of three cultivars decreased and the fruit firmness of 'Yumyung' was higher than that fo 'Mibeakdo' and 'Okubo' in the overall period. During the fruit development, the changes of total sugar amounts of each measured fractions were similar among peach cultivars. Arabinose and galactose were the predominant non-cellulosic neutral sugars in all the fractions including cell wall material of the three cultivars. There was an active relationship between the changes of flesh firmness in three cultivars and the mol % changes of rhamnose on 5 August which was the harvest date of 'Mibeakdo' and 'Okubo' fruits. The activity of soluble $\beta$-galactosidase was high at the early developmental stage and then dropped to a very low activity level in all cultivars. The activity of cell wall-bound $\beta$-galactosidase was high at the early developmental stage and then decreased continuously through the harvest date. In addition the changes of other glycosidase activities were similar among cultivars.

• Korean Journal of Medicinal Crop Science
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• v.8 no.3
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• pp.250-258
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• 2000

Hairy root cultures of Rheum undulatum L. induced by a co-culture with Agrobacterium rhizogenes ATCC15834 were established and the production of tannin in hairy roots was investigated. The growth of hairy roots was maximized in WPM liquid medium supplemented with 2 mg/L IAA, and 3% sucrose (pH 5.7). The highest yields of tannin were obtained from WPM medium containing 0.5 mg/L ABA, and 5% sucrose (pH 5.5). The growth and tannin production in hairy root cultures were influenced by the addition of elicitors to the medium. The addition of 50 mg/L chitosan enhanced the production of tannin with about 1.7 fold.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.4
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• pp.561-568
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• 2022

In this study, the mechanical properties and self-healing performance of cement mortar containing clinker binder, calcium sulfoaluminate(CSA), and sodium sulfate(Na₂SO₄) were evaluated. The mechanical properties of cement mortar were investigated by measuring compressive strength and flexural strength, and the healing performance was evaluated through hydrostatic water permeability test and gas diffusion test. In addition, the healing products precipitated in the cracks were visually observed through an optical microscope and a scanning electron microscope(SEM). As a result, the incorporation of the clinker binder-based inorganic additives improved the initial and 28-day strength by about 20 %. Depending on the healing performance evaluation method, there was a difference in the healing rate, and the healing rate showed a tendency to be underestimated. Nevertheless, CaCO₃ was precipitated as the main healing product inside the 0.3 mm crack when the inorganic additives were mixed with cement mortar, improving the self-healing performance.