• Journal of Periodontal and Implant Science
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• v.50 no.4
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• pp.238-250
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• 2020

Purpose: This study aimed to evaluate the biocompatibility and the mechanical properties of ultraviolet (UV) cross-linked and biphasic calcium phosphate (BCP)-added collagen membranes and to compare the clinical results of ridge preservation to those obtained using chemically cross-linked collagen membranes. Methods: The study comprised an in vitro test and a clinical trial for membrane evaluation. BCP-added collagen membranes with UV cross-linking were prepared. In the in vitro test, scanning electron microscopy, a collagenase assay, and a tensile strength test were performed. The clinical trial involved 14 patients undergoing a ridge preservation procedure. All participants were randomly divided into the test group, which received UV cross-linked membranes (n=7), and the control group, which received chemically cross-linked membranes (n=7). BCP bone substitutes were used for both the test group and the control group. Cone-beam computed tomography (CBCT) scans were performed and alginate impressions were taken 1 week and 3 months after surgery. The casts were scanned via an optical scanner to measure the volumetric changes. The results were analyzed using the nonparametric Mann-Whitney U test. Results: The fastest degradation rate was found in the collagen membranes without the addition of BCP. The highest enzyme resistance and the highest tensile strength were found when the collagen-to-BCP ratio was 1:1. There was no significant difference in dimensional changes in the 3-dimensional modeling or CBCT scans between the test and control groups in the clinical trial (P>0.05). Conclusions: The addition of BCP and UV cross-linking improved the biocompatibility and the mechanical strength of the membranes. Within the limits of the clinical trial, the sites grafted using BCP in combination with UV cross-linked and BCP-added collagen membranes (test group) did not show any statistically significant difference in terms of dimensional change compared with the control group.

• Journal of Environmental Science International
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• v.27 no.8
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• pp.621-629
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• 2018

Many chemically active species such as ${\cdot}H$, ${\cdot}OH$, $O_3$, $H_2O_2$, hydrated $e^-$, as well as ultraviolet rays, are produced by Dielectric Barrier Discharge (DBD) plasma in water and are widely use to remove non-biodegradable materials and deactivate microorganisms. As the plasma gas containing chemically active species that is generated from the plasma reaction has a short lifetime and low solubility in water, increasing the dissolution rate of this gas is an important challenge. To this end, the plasma gas and water within reactor were mixed using the air-automizing nozzle, and then, water-gas mixture was injected into water. The dissolving effect of plasma gas was indirectly confirmed by measuring the RNO (N-Dimethyl-4-nitrosoaniline, indicator of the formation of OH radical) solution. The plasma system consisted of an oxygen generator, a high-voltage power supply, a plasma generator and a liquid-gas mixing reactor. Experiments were conducted to examine the effects of location of air-automizing nozzle, flow rate of plasma gas, water circulation rate, and high-voltage on RNO degradation. The experimental results showed that the RNO removal efficiency of the air-automizing nozzle is 29.8% higher than the conventional diffuser. The nozzle position from water surface was not considered to be a major factor in the design and operation of the plasma reactor. The plasma gas flow rate and water circulation rate with the highest RNO removal rate were 3.5 L/min and 1.5 L/min, respectively. The ratio of the plasma gas flow rate to the water circulation rate for obtaining an RNO removal rate of over 95% was 1.67 ~ 4.00.

• Journal of the Korean Society of Costume
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• v.58 no.4
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• pp.128-138
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• 2008

The purposes of this study were to identify the effects of body satisfaction and self-esteem on the make-up degree of middle and high school girls. Self-administered questionnaire was used for data collection from 432 students. The results were as follows: 1) Most of middle and high school girls were in height of 161-165cm and weight of 56-60kg. Satisfaction level of middle and high school girls with their eyes was the highest and that of weight was the lowest. They showed strong intention to modify their appearances and were dissatisfied with their body. 2) Middle and high school girls' satisfaction level of home life self-esteem was the highest, but that of school life was the lowest. 3) Middle and high school girls used cosmetics to protect their skins and paid much attention to their skins. They collected cosmetics informations from their friends or family members, and began to use point make-ups from their middle school years. They purchased cosmetics at cosmetic specialty store or internet shopping mall frequently. Most of them spent less than 10,000 won monthly for cosmetics, and used lip gloss and ultraviolet rays interceptors over their face with basic cosmetics. 4) Expenditures for cosmetics, self-esteem on their appearances, and pocket money affected on make-up degree. Middle and high school girls who spent more money for cosmetics and more pocket money with higher self~esteem on their appearances showed higher degree of make-ups.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.12
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• pp.1849-1856
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• 2010

Glass/resin/glass laminate structures are used in the automobile, biological, and display industries. The sandwich structures are used in the micro/nanoimprint process to fabricate a variety of functional components and devices in fields such as display, optics, MEMS, and bioindustry. In the process, micrometer- or nanometer-scale patterns are transferred onto the substrate using UV curing resins. The demodling process has an important impact on productivity. In this study, we investigated the fracture behavior of glass/resin/glass laminates fabricated via UV curing. We performed measurements of the adhesion force and the interfacial energy between the mold and resin materials using the four-point flexural test. The bending-test measurements and the load-displacement curves of the laminates indicate that the fracture behavior is influenced by the interfacial energy between the mold and resin and the resin thickness.

• Toxicological Research
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• v.31 no.4
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• pp.363-369
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• 2015

We evaluated the antioxidant activity and anti-wrinkle effects of Aceriphyllum rossii leaf ethanol extract (ARLEE) in vitro using human dermal fibroblasts. The total polyphenol and flavonoid contents of ARLEE were 578.6 and 206.3 mg/g, respectively. At a concentration of $250{\mu}g/mL$, the electron-donating ability of ARLEE was 87.1%. In comparison with the vehicle, ARLEE treatment at $100{\mu}g/mL$ significantly increased type I procollagen synthesis (p < 0.01) by 50.7%. In vitro ARLEE treatment (10 mg/mL) inhibited collagenase and elastase activity by 97.1% and 99.2%, respectively. Compared with the control, ascorbic acid treatment at $100{\mu}g/mL$ significantly decreased matrix metalloproteinase (MMP)-1 protein expression (p < 0.01) by 37.0%. ARLEE treatment at $50{\mu}g/mL$ significantly decreased MMP-1 protein expression (p < 0.01) by 46.1%. Ascorbic acid and ARLEE treatments at $100{\mu}g/mL$ significantly decreased MMP-1 mRNA expression (p < 0.01) by 26.1% and 36.1%, respectively. From these results, we conclude that ARLEE has excellent antioxidant activity and even better anti-wrinkle effects than ascorbic acid in human dermal fibroblasts. These results suggest that ARLEE could be used in functional cosmetics for the prevention or alleviation of skin wrinkles induced by ultraviolet rays.

• Environmental Analysis Health and Toxicology
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• v.24 no.3
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• pp.219-229
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• 2009

The purpose of this study is to evaluate the skin whitening effect of Scirpi rhizama ethanol extract (SREE) in an animal model. For the experiment of the study, three brown guinea pigs weighing about 450 g to 550 g were exposed to ultraviolet-B rays on the backs at 500 $mJ/cm^2$ once a week, three consecutive weeks and the total quantity of light was 1,500 $mJ/cm^2$. The artificial tanning spots were divided into six different groups including normal (N), control (C), vehicle control (VC), positive control (PC), experimental 1 (E1, 1% SREE), experimental 2 (E2, 2% SREE) groups. Then, 30 ${\mu}L$ of SREE was transdermaly applied on the artificial tanning spots twice a day and 5 days a week for 8 weeks. With the result of a gross observation, it was found that the degree of pigmentation became apparently thinner in the group applied with E2, compared to the control or the vehicle control group. The melanin index of E2 group was significant lower than the control or the vehicle control group. In the observation with a light microscope, it was found that the degree of melanin pigmentation and S-100 protein expression considerably decreased in the groups applied with SREE, compared to the control or the vehicle control group. With the numerical analysis of melanin pigmentation and S-100 protein expression by using image-analysis software, it was found that the tendency was coincide with the results of microscopic observation.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.1
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• pp.117-122
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• 2004

Exessive UV radiation causes a lot of problems in our skin. In order to find out the alternative UV absorber that can safely be used in cosmetics, we have screened various natural extracts in terms of their UV absorbing effect. Some natural extracts, which possess antioxidative activities, have also been found to retard the oxidation process in our experiment. Natural compound such as 7-hydroxycymopol, baicalein, etc. could be transformed into adjuvant UV absorber by chemical modification. In cosmetics, its chemical stability against UV radiation, exposure to oxygen and other factors could be improved by using the silicone or W/S type emulsion. The values of MED (minimal erythema dose) were improved to 0.10 ${\pm}$ 0.02∼0.11 ${\pm}$ 0.02 by adding this natural extract into the cosmetic formulations. In conclusion, the results of the present study show that natural extracts could be used as an adjuvant UV absorber, if they are stabilized.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.6
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• pp.714-720
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• 2017

Exposure to ultraviolet (UV) radiation is associated with the development of adverse effects in skin. Among the three types of UV rays, UV-B causes the most damaging effects, inducing sunburn and penetrating the outer skin, resulting in DNA mutations and skin cancer. The objective of this study was to formulate a UV-protective film by incorporating Ecklonia cava extracts. Cells covered with the film were exposed to UV-B (50, 80, and $100mJ/cm^2$). To determine the protective effects of the film, we evaluated cell viability, intracellular ROS generation, and apoptosis. We found that all E. cava extracts absorbed UV light and exhibited protective effects against UV-B-induced photodamage. Among the protective films examined in this study, that incorporating an E. cava 70% ethanol extract (70EX) formed the most effective protection against UV-B in HaCaT cells. These findings suggest that the application of film containing E. cava extract could prevent UV-B-induced photodamage, and offer protection against the detrimental effects of UV radiation, thus maintaining physiological condition.

• The Journal of the Korea Contents Association
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• v.11 no.8
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• pp.14-22
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• 2011

It is important for the strategy of service to provide the health information in the environment that the healthcare has been changed focusing on the preventive medicine. Recently, the various applications of u-healthcare have been presented by researchers. In this paper, we proposed the health information monitoring system using the context sensors based band. By wearing the proposed hand, the health status is gathered and vital signals are transmitted to the connected UMPC. It can be easily monitored according to the user locations in real time. To provide the health index according to the temperature, the air conditioning, the illumination, the humidity, and the ultraviolet rays, we use the various XML links extracted from RSS of the Korea Meteorological Administration. The health information is analyzed in terms of factors, such as, the asthma index, the stroke index, the skin disease index, the pulmonary disease index, the pollen concentration index, and the city high temperature index. Ultimately, this paper suggests empirical application to verify the adequacy and the validity with the proposed system. Accordingly, the satisfaction and the quality of services will be improved the healthcare.

• Korean Journal of Rural Living Science
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• v.8 no.2
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• pp.119-124
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• 1997

In this study we tried to give a decision on propriety of working conditions, to present ideas on reducing work loads, and to grope for efficiency of agricultural works. For this we examined the actual working conditions of cultivating welsh onion in the summer ground. And we improved harmful factors that affect farmer's health by considering results of previous study and farmer's subjective sensation. And we measured. compared, and analyzed the farmer's work loads before and after improvement. The results of this study are as follows ; 1. According to examine the actual working conditions of cultivating welsh onion in the summer ground, farmers have experienced physical and mental chronic fatigue on the basis of farmer's appel to eye - fatigue and sun - burned skin on hot working environment including excessive ultraviolet rays, the rough ground condition, inconsistent arrangement of working stand and sorter, heavy - weared habits, and unsuitable working posture. 2. When we improved harmful factors that affect farmer's health, conformed the effects on important work efficiency index such as heart rate, electromyovolume, body temperature, and microclimate inside clothing and work loads were decreased by eliminating the hillock and obstacles of ground, decreasing the clothing weight, using proper clothing appliances such as hat and sunglasses, controlling height of working stand and sorter suitably, improving the working postures and methods as using assistant appliances, alloting the working time and sequence effectively and presenting the light gymnastic exercises and rest for fatigue restoration.