• The Korean Journal of Physiology and Pharmacology
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• v.3 no.3
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• pp.283-291
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• 1999

We have synthesized novel platinum (II) coordination complex containing cis-1,2-diaminocyclohexane (DACH) as a carrier ligand and 1,2-bis(diphenylphosphino)ethane (DPPE) as leaving group. Furthermore, nitrate was added to improve the water-solubility. A new series of [Pt(cis-DACH)(DPPE)] $2NO_3(PC)$ was evaluated its antitumor activity on various MKN-45 human gastric adenocarcinoma cell-lines and normal primary cultured kidney cells. The new platinum complex demonstrated high efficacy in the cytotoxicity on MKN-45 cell-lines as well as adriamycin-resistant (MKN-45/ADR) and cisplatin-resistant (MKN-45/CDDP) cells. The cytotoxicities of PC were found quite less than those of cisplatin in rabbit proximal renal tubular cells, human renal cortical cells and human renal cortical tissues using MTT assay, $[^3H]-thymidine$ uptake and glucose consumption tests. Based on these results, this novel platinum (II) coordination complex, was considered as better a valuable lead for improving antitumor activities with low nephrotoxicities in the development of a new clinically available anticancer chemotherapeutic agents.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.283-286
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• 2003

The electric traction load is quite differ from general power system load which is single-phase, high-speed heavy load receiving power from 3-phase power system and also has variable load characteristics over time and space. Therefore, there are inevitably power quality problems such as steady state or transient voltage drop, voltage imbalance and harmonic distortion. In addition, it is expected that transient voltage sag could affect the safety of feeding system. Thus, in this paper transient analysis and voltage sag compensation of AT(Auto Transformer) feeding system are studied. The fault study of traction network is analysed by using PSCAD/SMTDC simulation tool. In addition, application of DVR in electric traction system is proposed to compensate the voltage sag of traction network which is occurred by the fault of utility source. The results of fault study will be a useful research works for operation and setting of electric traction relay. Also, it can be shown that application of the DVR in electric system is very useful to compensate the voltage sag from the result of related simulated work. The results of study will be a useful research works for management and planning of power quality in electric traction system.

• Elastomers and Composites
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• v.49 no.4
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• pp.275-283
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• 2014

Butyl rubber is used as an adhesive and it is mainly used in the form of sheets. The goal of this study is to design an extrusion die for the butyl rubber sheets using computer simulation. The extrusion die for the butylrubber sheets consists of manifold area and land area. In the manifold area, flows are spread from the entrance of the extrusion die to the land area. In the land area, flows become stable to the flow direction and uniform sheet can be obtained. Island area is being installed in the land area to get uniform flow. Four parameters, angle of manifold, length of manifold, length of land and island, were examined in the computer simulation. The optimum geometry of the extrusion die is derived which has a uniform flow in the width direction of the die.

• Transactions on Electrical and Electronic Materials
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• v.13 no.1
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• pp.39-42
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• 2012

To study the physical and chemical properties, solid solutions of $(Sr_{1-x}Ba_x)NdFe{^{3+}}_{1-\tau}Fe{^{4+}}_{\tau}O_{4-y}$ system with x=0.0(SBN-0), 0.1(SBN-1), 0.2(SBN-2) and 0.3(SBN-3) were synthesized in air at 1,473 K and annealed in air at 1,073 K for 24 h. X-ray powder diffraction assured that the four samples had tetragonal symmetries (I4/mmm). Their lattice volumes increased gradually with x values. Nonstoichiometric chemical formulas were formulated using the data such as $\tau$(amount of $Fe^{4+}$ ion) and y(oxygen deficiency) values using Mohr salt analysis. It was found out that all the four samples had excessive oxygen (4-y>4.0). All the samples started to lose some of their oxygen at around 613K(TG/DTA thermal analysis). They exhibited semiconductivities in the temperature range of around 283-1173K. All the four specimens had sufficient tensile strength to endure the force of 19.6 N (2 kg of weights) and the conductivity values of the ECIAs which were painted on pieces of glass with the area of $150mm^2$ ($10mm{\times}15mm$) and it was in the order of ECIA-0${\rightarrow}$ECIA-1${\rightarrow}$ECIA-2${\rightarrow}$ECIA-3 at a constant temperature.

• Journal of Korean Society on Water Environment
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• v.21 no.3
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• pp.277-283
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• 2005

This paper aimed to compare the daily water quality as well as the hydrological data gathered for the past two years (2000 to 2001) between the two influent rivers of Paldang reservoir. The analysis also has been carried out to draw out the factors that affect the water quality at the dam site, where the main drinking water drawing point is located. The relationship between total amount of monthly rainfall and monthly inflow showed $r^2=0.74$ (p<0.05). The highest peak of inflow of influent rivers recorded in August and September (in the year of 2000) and July and August (2001). Average inflows of influent rivers in 2000 and 2001 are calculated at 209.0, 161.5 CMS (Bughangang), 268.6, 148.2 CMS(Namhangang), and 7.8, 5.0 CMS (Gyeongancheon). The formula which was driven from the relationship between inflow and COD load of influent rivers, explained that COD concentration in general increased with the inflow. But during the rainy seasons (July, August, and September), COD concentration decreased according to the increase of inflow. The daily rainfall and COD concentration(or load) during the rainy season (August and September in the year of 2000, July and August in 2001) indicated that the peak of COD load correspond with the rainfall, which decreased sharply after 3 or 4 days. The reason was thought that the high COD load was diluted rapidly by the rain flow. Water temperature, pH and conductivity measured at dam site decreased obviously when the inflow sharply increased. Peak period of total phosphorus concentration coincided with that of inflow. In rainy season, chlorophyll-a concentration decreased obviously as the inflow increased. The reason can be ascribed to the flushing effect caused by the operation of floodgate.

• Biomolecules & Therapeutics
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• v.27 no.3
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• pp.283-289
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• 2019

Brain aging induces neuropsychological changes, such as decreased memory capacity, language ability, and attention; and is also associated with neurodegenerative diseases. However, most of the studies on brain aging are focused on neurons, while senescence in astrocytes has received less attention. Astrocytes constitute the majority of cell types in the brain and perform various functions in the brain such as supporting brain structures, regulating blood-brain barrier permeability, transmitter uptake and regulation, and immunity modulation. Recent studies have shown that SIRT1 and SIRT2 play certain roles in cellular senescence in peripheral systems. Both SIRT1 and SIRT2 inhibitors delay tumor growth in vivo without significant general toxicity. In this study, we investigated the role of tenovin-1, an inhibitor of SIRT1 and SIRT2, on rat primary astrocytes where we observed senescence and other functional changes. Cellular senescence usually is characterized by irreversible cell cycle arrest and induces senescence- associated ${\beta}$-galactosidase (SA-${\beta}$-gal) activity. Tenovin-1-treated astrocytes showed increased SA-${\beta}$-gal-positive cell number, senescence-associated secretory phenotypes, including IL-6 and IL-$1{\beta}$, and cell cycle-related proteins like phospho-histone H3 and CDK2. Along with the molecular changes, tenovin-1 impaired the wound-healing activity of cultured primary astrocytes. These data suggest that tenovin-1 can induce cellular senescence in astrocytes possibly by inhibiting SIRT1 and SIRT2, which may play particular roles in brain aging and neurodegenerative conditions.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.1
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• pp.61-69
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• 2019

All the parts of lotus, including the seed, rhizome, leaf, stalk, petal, anther, pericarp, and fruit receptacle, have been used in traditional medicine system as a health beneficial supplement. However the most usually used from lotus plant is only the root. Therefore in this study, it will be discussed more the utilization of other parts of the lotus, namely the flower of lotus. The petals and stamens of lotus actually are also rich in bioactive components such as flavonoids and alkaloids, are used in the treatment of tissue inflammation, cancer, skin disease, and also for us as antidotes. One of the biotechnological process that can be used to improve the nutritional content, sensory, and also antioxidant activities is fermentation process. The final product desired from the fermentation process in this study is vinegar. The microbial strain powder used is Uinkin fermented powder with three variations of fermentation. The variations given in this study were initial sugar 32%, 24%, and 14% with the same fermentation temperature, $35^{\circ}C$ for 3 months. The results obtained showed that the pH value and sugar content of products during the fermentation process were decreasing during the fermentation process, with total polyphenol content of $283.7{\pm}97.6mg/100g\;QAE$, and total flavonoid content of $3.3{\pm}0.0mg/100g\;QAE$. For the DPPH radical scavenging ability of the fermentation product also increased in a concentration dependent manner, with ORAC activity of the product showed a high activity of $20.7{\pm}0.41{\mu}M$ TE. Therefore, fermentation process can be the one of method for improving the product. The efficiency of lotus flower vinegar fermentation can be reached with an initial sugar condition of 25% (sample B).

• Nutrition Research and Practice
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• v.17 no.2
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• pp.269-283
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• 2023

BACKGROUND/OBJECTIVES: This study aimed to examine the food security status of urban poor adolescents and its association with diet quality. SUBJECTS/METHODS: A cross-sectional survey was conducted among 188 adolescents aged 13-18 yrs living in Kuala Lumpur, Malaysia. Household food insecurity and dietary intake data were collected using the Radimer/Cornell hunger and food insecurity instrument and 2-day 24-h dietary recalls, respectively. Diet quality was determined using the Malaysian Healthy Eating Index (HEI). Weight and height were measured and body mass index-for-age, as well as height-for-age z scores were calculated. RESULTS: The present study revealed that 47.9% of the adolescents experienced household food insecurity, 24.5% experienced individual food insecurity, 18.6% household food security, and 9.0% child hunger. The mean score of diet quality was 56.83 ± 10.09, with a significantly lower HEI score among food insecure adolescents (household food insecure, individual food insecure, and child hunger) than household food secure adolescents (P = 0.001). The differences between food secure and food insecure households were found to be significant for energy (P = 0.001) and nutrients including proteins (P = 0.006), carbohydrates (P = 0.005), dietary fiber (P = 0.001), folate (P < 0.001), and vitamin C (P = 0.006). The multiple linear regression showed that adolescents who experienced food insecurity (β = -0.328; P = 0.003) were found to be significantly associated with poor diet quality (F = 2.726; P < 0.01), wherein 13.3% of the variation in the diet quality was explained by the food security status. CONCLUSIONS: Experiencing food insecurity contributed to poor diet quality among urban poor adolescents. Further longitudinal studies are needed to comprehensively understand this association to improve food insecurity and diet quality among urban poor communities.

• Korean Journal of Agricultural Science
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• v.51 no.3
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• pp.283-294
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• 2024

The objective of this study was to investigate the effect of supplementing concentrates in a forage-based diet on methane emissions of pregnant Hanwoo heifers. Twenty-one pregnant Hanwoo heifers (481 ± 42.4 kg) were divided into two groups: 1) a group receiving forage only (control, CON) and 2) the other group receiving forage with 4 kg of a concentrate mix (treatment, TRT). Methane (CH₄) concentration was measured using a laser methane detector, following an 18-d adaptation period, according to previously established protocols. Feed intake was recorded throughout the experimental period. Ruminal fluid was collected and analyzed for pH, ammonia-nitrogen (NH₃-N), and volatile fatty acid (VFA). The TRT exhibited higher dry matter and neutral detergent fiber intake than CON (p < 0.05) with elevated NH₃-N (p < 0.001) and total VFA concentrations (p = 0.013). The proportions of butyrate, valerate, and iso-valerate were higher in TRT than CON (p < 0.05). Notably, CH₄ concentrations per kg dry matter intake was lower in the TRT group, both from respiration and eructation (p < 0.05). In conclusion, supplementing concentrates in a low-quality forage-based diet for pregnant Hanwoo heifers fulfills nutrient requirements and reduces CH₄ emissions, suggesting a potential strategy to reduce environmental impact of Hanwoo production.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.46 no.3
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• pp.283-294
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• 2020

In this study, in order to increase the utilization of Citrus junos seeds, which account for 13% of the weight ratio of Citrus junos ripened fruit, but are mostly discarded and not utilized, the efficacy of skin beauty of Citrus junos seed oil extracted by cold pressing was studied. Citrus junos seed oil was found to contain approximately 74% of unsaturated fatty acids consisting mainly of oleic acid and linoleic acid, and limonene, which is mainly contained in Citrus junos peel, contained a very low content of about 0.0187%. As a result of evaluating the DPPH radical scavenging activity of Citrus junos seed oil, 26% of DPPH radical scavenging ability was confirmed at 5% concentration of Citrus junos seed oil. To confirm the anti-inflammatory effect, as a result of testing RAW 264.7 cytotoxicity test and NO production for Citrus junos seed oil, NO production was suppressed by 53% at a concentration of 0.05% that does not show cytotoxicity. In addition, in the RBL-2H3 cytotoxicity and β-hexosaminidase release inhibitory efficacy test for anti-allergic efficacy confirmation, it was confirmed that β-hexosaminidas release was suppressed by 26% at a concentration of 0.05% that did not show cytotoxicity. Lastly, in the human skin application test result of O/W emulsion containing 5% of Citrus junos seed oil, it showed higher skin moisturizing effect than the control emulsion containing the same amount of caprylic/capric triglyceride. Therefore, it is thought that Citrus junos seed oil might be used as a excellent skin care material.