• Toxicological Research
• /
• v.23 no.4
• /
• pp.405-413
• /
• 2007

This study was to investigate single and repeated-dose toxicities of Tensolin-$F^{(R)}$, an anti-wrinkle agent, in Sprague-Dawley (SD) rats or ICR mice. In single-dose oral toxicity study, the test materials were administered once by gavage to male and female SD rats at dose levels of 0 and 2,000 mg/kg. No dead animals and abnormal necropsy findings were found in control and Tensolin-$F^{(R)}$ treated group. Therefore, the approximate lethal dose of Tensolin-$F^{(R)}$ was considered to be higher than 2,000 mg/kg in rats. In the 4-week repeated oral toxicity study, the test material was administered once daily by gavage to male and female ICR mice at dose levels of 0, 25, 50 and 100 mg/kg/day for 4-weeks. In the results, no abnormality was observed in mortality, clinical findings, body weight changes, food and water consumptions, opthalmoscopic findings, necropsy findings, histopathological findings. In hematological analysis, there was a trend of increase in reticulocyte at male 25 mg/kg, although such changes were in normal ranges. On the other hand, there was a trend of decrease in hemoglobin at female 50, 100 mg/kg, such changes were in normal ranges. In addition, serum biochemical parameters including sodium, BUN and chloride increased at 25, 50 and 100 mg/kg. Relative organ weights of right testis, brain, lung and left epididymis were increased in 100 mg/kg groups of male rats in contrast to not change in female groups. However, these changes of relative organ weights, hematological and serum biochemical parameters were not accompanied with related signs such as histopathological changes or clinical findings. In conclusion, 4-week repeated oral dose of Tensolin-$F^{(R)}$ to ICR mice did not cause apparent toxicological change at the dose of 25, 50, 100 mg/kg body weight. Consequently the no-observed-adverse-effect level (NOAEL) for Tensolin-$F^{(R)}$ in ICR mice following gavage for at least 4-week is higher than 100 mg/kg/day.

• Journal of the Korean Applied Science and Technology
• /
• v.30 no.2
• /
• pp.272-279
• /
• 2013

The fermented puer tea leaves were high concentrated extracted with 50% ethanolic solution in this study. Also, evaluating the anti-oxidative activity and anti-aging effect of this extract, we expected to apply the cosmetic industry. The yield of fermented puer tea extract was 17.9%. The total polyphenol content was 37.5%, tannin content was 7.5%, polysaccharide was 17.9%, unknown compound was 22%, and water content was 8%. Anti-oxidative activity (in-vitro) of fermented puer tea extract by DPPH method was $33.7{\pm}1.8%$ in 30mg/mL, $39.4{\pm}2.2%$ in 50mg/mL respectively. Therefore, we could know that anti-oxidative activity of fermented puer tea extract was effect higher than tocopheryl acetate and greentea extract. The collagen synthesis activity (in-vitro) of fermented puer tea extract was increased with $102.9{\pm}9.9%$ in 1 mg/mL, $111.5{\pm}9.9%$ in 5 mg/mL, $122.7{\pm}12.2%$ in 10 mg/mL, $131.5{\pm}13.7%$ in 30 mg/mL (*p-value£0.05, n=3). Skin moisturizing activity of fermented puer tea extract after application 8 hours was increased 38.5% higher than control samples both tocopheryl acetate and greentea extract. Total moisturizing effect was increased about 32.7% compared to before treatment. Fermented puer tea extract of this study can be applied to the skin care cosmetics industry.

• Korean Journal of Materials Research
• /
• v.23 no.4
• /
• pp.233-239
• /
• 2013

We collected Seokganju minerals (regions in Gyeryong Mountain, Sangsin-ri, Banpo-myeon, Gongju Chungcheongnam-province), which were used as natural color pigments for grayish-blue during the 15th~16th centuries of the Joseon era, and investigated their crystallographic features to develop a black pigment having a spinel structure. By a Raman analysis, the color of Seokganju under transparent glaze as a pigment for painting was black because hematite ($Fe_2O_3$) in Seokganju was converted to magnetite ($Fe_3O_4$) However, Seokganju into the transparent glaze as a pigment was brown because of hematite ($Fe_2O_3$) and small amounts of maghemite (${\gamma}-Fe_2O_3$) in Seokganju minerals. Only Seokganju mineral is used, it is not suitable for black pigment into the transparent glaze. This study tried to develop a spinel crystal black pigment stabilized by Seokganju with CoO, $Cr_2O_3$, NiO, and $MnO_2$ at $1280^{\circ}C$. A Raman spectroscopy analysis was performed to verify the presence of Mn The results showed that it existed as spinel, and two crystal phases $CoFe_2O_4$ and $MnFe_2O_4$ were mixed. $CoFe_2O_4$ spinel has a dark grayish black color and $MnFe_2O_4$ spinel has a greenish black color, and these two appeared as black. The color of a specimen calcined by adding 6 wt% of pigment mixed with 5 wt% of $MnO_2$ added to lime glaze was analyzed with a UV spectrophotometer. When applying the color pigment, it appeared black stabilized with $L^*$24.23, $a^*$ 0.12, $b^*$ -2.29 at $1260^{\circ}C$ oxidative calcination, With $1240^{\circ}C$ reduction firing, it is appeared black stabilized with low brightness of $L^*$ 23.13, $a^*$ -1.12, $b^*$ 0.54.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.62 no.5
• /
• pp.39-46
• /
• 2020

This study evaluated the nitrogen oxide (NO_x) removal efficiency by air purification concrete blocks with titanium dioxide (TiO₂). The concrete in the mixtures had a 30% water:cement ratio, to which TiO₂ was added at 0%, 5%, and 10% of cement weight. The compressive strength reduction rate and removal efficiency of NO_x were investigated. The result of the compressive strength test in the study indicated that addition rate of TiO₂ did not lead to signifcant effect. In terms of the average removal efficiency of NO_x, mix No. 1 using a TiO₂ mixing ratio of 0% had a removal efficiency of 0.57% on average; thus, the removal effect w as not significant. For the other samples prepared by mixing, the average removal efficiencies for mix No. 2 (5% TiO₂) were 58.86% and 62.05% for normal and washing surface treatments, respectively, and those of sample No. 3 (10% TiO₂) were 59.94% and 67.61%. mixs No. 4 (5%) and No. 5 (10%), in which TiO₂ diluted with distilled water was sprayed onto the block surface, had an average NO_x removal efficiency of 61.72% and 68.48%, respectively. In terms of NOx removal efficiency, Mixs No. 3 and No. 5 with 10% TiO₂ were better than Mixs No. 2 and No. 4 with 5% TiO₂. In addition, analyzing the NO_x removal efficiency results from the fixing method, it was capable to apply mixing (washing) and the diluted spray methods. Therefore, it was found that the diluted spray method applied in this study can be employed in any manufacture of air purification concrete blocks.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.14 no.3
• /
• pp.253-266
• /
• 2016

In accordance with the classification system of radioactive waste in Korea, all the disused sealed radioactive sources (DSRSs) fall under the category of EW, VLLW or LILW, and should be managed in compliance with the restrictions for the disposal method. In this study, the management and disposal method are drawn in consideration of half-life of radionuclides contained in the source and A/D value (i.e. the activity A of the source dividing by the D value for the relevant radionuclide, which is used to provide an initial ranking of relative risk for sources) in addition to the domestic classification scheme and disposal method, based on the characteristic analysis and review results of the management practices in IAEA and foreign countries. For all the DSRSs that are being stored (as of March 2015) in the centralized temporary disposal facility for radioisotope wastes, applicability of the derivation result is confirmed through performing the characteristic analysis and case studies for assessing quantity and volume of DSRSs to be managed by each method. However, the methodology derived from this study is not applicable to the following sources; i) DSRSs without information on the radioactivity, ii) DSRSs that are not possible to calculate the specific activity and/or the source-specific A/D value. Accordingly, it is essential to identify the inherent characteristics for each of DSRSs prior to implementation of this management and disposal method.

• Journal of agriculture & life science
• /
• v.44 no.5
• /
• pp.129-135
• /
• 2010

This experiment was carried out to commercialize an irrigation control system by finding out problems and solving them in application of a nutrient supply system through this experiment. Its efficiency had been tested through hydroponic cultivation of tomato and cucumber using this system in the farmer's plastic house (1-2W, 20a : Yanggyo-ri, Oseong-myeon Gyeonggi-do) from November. 2006, too. In the first cultivation, tomato seeds (cultivar Coco, Takii Seed Co. Japan) were sowed on November 8, 2006, and transplanted on January 8, 2007. and then, in the second, cucumber (Chuichong, Nongwoo Seed Co.) were cultivated in the same plastic house (sowing date : June 27, transplanting date : July 13). In the third, another cucumber cultivar (Jo-woon, Dongbu-hannong Seed Co.) were cultivated (sowing date : September 5, transplanting date : September 23). All of seedlings were transplanted on perlite bag ($W340{\times}L1,200{\times}H150mm$, 40L). By using this system, 971 boxes (5 kg/box) of tomato were produced and sold, and then total income was 5,466 thousand won per 10a. On the second cultivation, total amount of cucumber production was 489 boxes (50 ea/box), and total income was 7,380 thousand won. On the third cultivation, total amount of production was 67 boxes (100 ea/box), and total income was 1,854 thousand won. On the other hand, this system saved irrigated water by 50% ($4,000{\rightarrow}2,000L/10a/day$) in tomato cultivation, and by 44%($4,500{\rightarrow}2,500L/10a/day$) in cucumber cultivation. It also saved cost of nutrients by 50% in tomato ($1,648{\rightarrow}824thousand\;won/10a$), and 44% in cucumber ($1,648{\rightarrow}725thousand\;won/10a$). Furthermore this irrigation system maintained moisture content in perlite bag stable during cultivation period. Therefore, this system was successfully applied on farmer's greenhouse without a problem and can be commercialized for farmers.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.47 no.2
• /
• pp.139-145
• /
• 2021

Plant-derived exosome-like nanovesicles (PELNs) are known to include various biological activities and possess high biocompatibility. Because PELNs can influence immune responses, cell differentiation, and proliferation regulation, they can be applied in multiple industries. However, the studies on the skin physiological of exosome-like nanovesicles derived from plant callus are insignificant compared to nanovesicles derived from mammalian cells. In this study, callus was induced from apple fruit (Malus domestica), and exosome-like nanovesicles (ACELNs) were isolated for improving skin barrier and anti-aging. The yield of ACELNs was 6.42 × 10⁹ particles/mL, and the particle size was ranged from 100 to 200 nm. HDF cells and HaCaT cells were concentration-dependent, increased in cell, and decreased in cytotoxicity. The cornified envelope formation was significantly increased compared to the control group. The COL1A1 expression and the FBN1 expression in HDF cells were increased. In addition, the ACELNs promoted collagen biosynthesis in UVA-irradiated HDF cells. These results might be considered as potential materials that could improve skin barrier and prevent skin aging.

• Journal of the Society of Disaster Information
• /
• v.19 no.2
• /
• pp.344-351
• /
• 2023

Purpose: This study aimed to evaluate the effectiveness of a dielectric barrier discharge (DBD) plasma module for sterilizing airborne bacteria in indoor spaces and measure the concentration of ozone generated during plasma discharge. Method: The DBD plasma module was installed in a 76m³ space, and air samples were collected under various discharge times to compare the reduction of airborne bacteria. Result: The results showed a significant decrease in airborne bacteria, ranging from 92.057% to 99.999%, with an average ozone concentration of 0.04 ppm, below the reference value. Conclusion: The study suggests that plasma discharge can be used as a means of preventing the spread of airborne bacteria and viruses, while ensuring safety for human exposure.

• The Journal of Korean Academy of Prosthodontics
• /
• v.51 no.4
• /
• pp.276-283
• /
• 2013

Purpose: The purpose of this study was to investigate the fit and screw joint stability between Ready-made abutment and CAD-CAM custom-made abutment. Materials and methods: Osstem implant system was used. Ready-made abutment (Transfer abutment, Osstem Implant Co. Ltd, Busan, Korea), CAD-CAM custom-made abutment (CustomFit abutment, Osstem Implant Co. Ltd, Busan, Korea) and domestically manufactured CAD-CAM custom-made abutment (Myplant, Raphabio Co., Seoul, Korea) were fabricated five each and screws were provided by each company. Fixture and abutments were tightening with 30Ncm according to the manufacturer's instruction and then preloding reverse torque values were measured 3 times repeatedly. Kruskal-Wallis test was used for statistical analysis of the preloading reverse torque values (${\alpha}=.05$). After specimens were embedded into epoxy resin, wet cutting and polishing was performed and FE-SEM imaging was performed, on the contact interface. Results: The pre-loading reverse torque values were $26.0{\pm}0.30Ncm$ (ready-made abutment; Transfer abutment) and $26.3{\pm}0.32Ncm$ (CAD-CAM custom-made abutment; CustomFit abutment) and $24.7{\pm}0.67Ncm$ (CAD-CAM custom-made abutment; Myplant). The domestically manufactured CAD-CAM custom-made abutment (Myplant abutment) presented lower pre-loading reverse torque value with statistically significant difference than that of the ready-made abutment (Transfer abutment) and CAD-CAM custom-made abutment (CustomFit abutment) manufactured from the same company (P=.027) and showed marginal gap in the fixture-abutment interface. Conclusion: Within the limitation of the present in-vitro study, in domestically manufactured CAD-CAM custom-made abutment (Myplant abutment) showed lower screw joint stability and fitness between fixture and abutment.

• Journal of Animal Science and Technology
• /
• v.54 no.5
• /
• pp.363-368
• /
• 2012

This study was conducted to investigate the effects of dietary garlic and may flower powder on $CO_2$ and $CH_4$ emission by Hanwoo cows fed TMR (Total Mixed Ration) based diet. Animals were housed in a hood-type respiration chamber and the environmental temperature was maintained at $20^{\circ}C$. Gases were measured for 24 hours using the multi-detector instrument gas monitoring system (Mamos-300, Australia). The treatments composed of groups with no intake of garlic and may flower powder (Control), with intake of garlic at 0.5% of DM (T1), with intake of garlic at 1% of DM (T2), with intake of may flower at 0.5% of DM (T3), with intake of may flower at 1% of DM (T4), with intake of garlic and may flower at 0.5% of DM (T5) and with intake of garlic and may flower at 1% of DM (T6). The results indicated that $CO_2$ emission in T3 was 53% lower than that of control (p<0.05), and $CH_4$ emissions was 57% lower than control (p<0.05). Also, the hourly pattern of $CO_2$ and $CH_4$ emissions in T3 showed the least difference with all treatments. Gas emissions pattern peaked after 1 hour of feeding and this gap was wider in the afternoon than in the morning hours.