• Journal of the Society of Cosmetic Scientists of Korea
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• v.29 no.2 s.43
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• pp.67-77
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• 2003

Two categories of cosmetic products, cosmetics and quasi-drugs, have been established by the Ministry of Health, Labor and Welfare (MHLW) in Japan. Japanese pharmaceutical law has defined that products categorized as cosmetics do not exhibit any effects on human skin. In fact, cosmetic products are not permitted to claim any efficacy. On the other hand, products in the quasi-drug category can claim several efficacies such as anti-inflammatory effects, whitening/lightning effects, hair growth effects and so on. Unfortunately, the Japanese MHLW has not yet approved the efficacy of anti-aging/anti-wrinkle effects as a claim point. However, the population is aging, and the demand for anti-aging/anti-wrinkle products is increasing year by year. Japanese cosmetic companies have proposed to the MHLW that anti-aging/anti-wrinkle agents be approved as a claim concept of a quasi-drug. However, unified evaluation methods for anti-aging/anti-wrinkle effects have not been established. Currently, each company evaluates the efficacy of products/materials using their own original methods. Thus, to request approval of the MHLW, the establishment of a unified evaluation method is needed. Consequently, the Japan Cosmetic Industry Association (JCIA) has established a task force to develop guidelines for evaluating anti-wrinkle effects in 1998. In conclusion, the JCIA would like to adopt visual and image analysis scales to evaluate the anti-wrinkle effects objectively. Generally, wrinkles are roughly classified into three groups as fine wrinkles, linear deep wrinkles and crow's feet. However, academic societies of dermatology or cosmetics have not yet established a definition of wrinkles in Japan. Thus, in advance of setting up an evaluation method, the definition of wrinkles f3r evaluation must be decided. Wrinkles are defined by the task force of the JCIA as follows; furrows that people can recognize visually and that appear on the forehead, the corners of the eyes and the backs of the neck with aging. In addition, furrows are emphasized by exposure to solar light and by dry conditions. Visual evaluation is the most sensitive method and can be applied to most types of wrinkles. However, visual evaluation is hard to express digitally as results. Besides, in the case of image analysis, comparisons of data obtained from distinct examinations can not be done, because data from image analysis are relative values. Thus, to enhance the reliability of the evaluations, the adoption of an objective scale was required. The principle of the evaluation method is to analyze images taken from silicone replicas of wrinkle areas using several parameters, such as the proportion of the wrinkle $area({\%})$, the mean depth of the wrinkles (mm), the mean depth of the deepest wrinkle (m) and the deepest point on the deepest wrinkle. Lights are shown on the skin replica from an orthogonal direction of the main orientation of the wrinkle, and the resulting shadow images are quantified by the image analysis method. To increase the precision of the data or to allow comparisons of independent examinations, a scale with furrows of several depths, 200, 400, 600, 800, and $1000{\mu}m$, is adapted in the evaluation system. I will explain the guidelines established by the JCIA in the presentation.

• Journal of Korean Dental Science
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• v.7 no.2
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• pp.49-57
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• 2014

Purpose: To evaluate the effect of different surface treatment methods (yttria-tetragonal zirconia polycrystal [Y-TZP] primers, air-abrasion, and tribochemical surface treatment) on the shear bond strength between (Y-TZP) ceramics and etch-and-rinse non-10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing resin cements. Materials and Methods: Y-TZP ceramic surfaces were ground flat with 600-grit silicone carbide abrasives paper and then divided into seven groups of ten. They were treated as the following: untreated (control), Monobond Plus (IvoclarVivadent), Z-PRIME Plus (Bisco Inc.), ESPE Sil with CoJet (3M ESPE), air-abrasion, Monobond Plus with air-abrasion, and Z-PRIME Plus with air-abrasion. The surface of Y-TZP specimens was analyzed under a scanning electron microscope (SEM). Non-MDP-containing cements were placed on the surface-treated Y-TZP specimens. After thermocycling, shear bond strength test was performed. Bond strength values were statistically analyzed using one-way analysis of variance and Student-Newman-Keuls multiple comparison test (P<0.05). Result: The Z-PRIME Plus treatment in combination with air-abrasion produced the highest bond strength ($14.94{\pm}1.70MPa$) followed by Monobond Plus combined with air-abrasion ($10.70{\pm}1.71MPa$), air-abrasion ($10.47{\pm}1.60MPa$), ESPE Sil after CoJet treatment ($10.38{\pm}0.87MPa$), Z-PRIME Plus application ($10.00{\pm}1.70MPa$), and then Monobond Plus application ($9.25{\pm}0.86MPa$). The control ($6.70{\pm}1.49MPa$) indicated the lowest results (P<0.05). The SEM results showed different surface morphologies according to surface treatment methods compared with the Y-TZP control. Conclusion: The shear bond strength between the Y-TZP ceramic and the non-MDP-containing resin cement was the greatest when the surface was treated with air-abrasion and MDP-containing Z-PRIME Plus primer.

• Physical Therapy Korea
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• v.13 no.4
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• pp.71-78
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• 2006

This study examined the effects of socket flexion angle in trans-tibial prosthesis on stump/socket interface pressure. Ten trans-tibial amputees voluntarily participated in this study. F-socket system was used to measure static and dynamic pressure in stump/socket interface. The pressure was measured at anterior area (proximal, middle, and distal) and posterior area (proximal, middle, and distal) in different socket flexion angles ($5^{\circ}$, $0^{\circ}$, and $10^{\circ}$). Paired t-test was used to compare pressure differences in conventional socket flexion angle of $5^{\circ}$ with pressures in socket flexion angles of $0^{\circ}$ and $10^{\circ}$ (${\alpha}$=.05). Mean pressure during standing in socket flexion angle of $10^{\circ}$ decreased significantly in anterior middle area (19.7%), posterior proximal area (10.4%), and posterior distal area (16.3%) compared with socket flexion angle of $5^{\circ}$. Mean pressure during stance phase in socket flexion angle of $0^{\circ}$ increased significantly in anterior proximal area (19.3%) and decreased significantly in anterior distal area (19.7%) compared with socket flexion angle of $5^{\circ}$. Mean pressure during stance phase in socket flexion angle of $10^{\circ}$ decreased significantly in anterior proximal area (19.6%) and increased significantly in anterior distal area (8.2%) compared with socket flexion angle of $5^{\circ}$. Peak pressure during gait in socket flexion angle of $0^{\circ}$ increased significantly in anterior proximal area (23.0%) compared with socket flexion angle of $5^{\circ}$ and peak pressure during gait in socket flexion angle of $10^{\circ}$ decreased significantly in anterior proximal area (22.7%) compared with socket flexion angle of $5^{\circ}$. Mean pressure over 80% of peak pressure ($MP_{80+}$) during gait in socket flexion angle of $0^{\circ}$ increased significantly in anterior proximal area (23.9%) and decreased significantly in anterior distal area (22.5%) compared with socket flexion angle of $5^{\circ}$. $MP_{80+}$ during gait in socket flexion angle of $10^{\circ}$ decreased significantly in anterior distal area (34.1%) compared with socket flexion angle of $5^{\circ}$. Asymmetrical pressure change patterns in socket flexion angle of $0^{\circ}$ and $10^{\circ}$ were revealed in anterior proximal and distal region compared with socket flexion angle of $5^{\circ}$. To provide comfortable and safe socket for trans-tibial amputee, socket flexion angle must be considered.

• Proceedings of the Korean Environmental Health Society Conference
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• 2001.11a
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• pp.19-29
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• 2001

Nutrients are key environmental factors in marine ecosystem. They limit algal growth when at low concentrations and cause algal bloom when at high contents. They also control the growth and succession of many other biota including bacteria and zooplankton, either directly or indirectly. Nutrient contents therefore affect both the structure and functions of marine ecosystem. To study the contents and distribution of nutrients in Chinese Bohai Sea, two cruise surveys were undertaken in August 2000 (summer) and January 2001 (winter), respectively. A total of 595 water samples were collected from 91 sites. After collection the samples were transported to the laboratory and five nutrients, i.e., nitrate, nitrite, ammonia, phosphate and silicate, were analyzed. The results showed that tile average concentration of total inorganic nitrogen (TIN) in Bohai Sea in winter (6.5293.717 ${\mu}$mol$.$l$\^$-1/) was significantly higher than that in summer (3.717 ${\mu}$mol$.$l$\^$-1/). The phosphorus concentration in winter (0.660 ${\mu}$mol$.$l$\^$-1/) was also significantly higher than that in summer (0.329 ${\mu}$mol$.$l$\^$-1/). Mean silicate concentration in winter (7.858 ${\mu}$mol$.$l$\^$-1/) was not significantly different from that in summer (7.200 ${\mu}$mol$.$l$\^$-1/). Nutrients also varied considerable among different areas within Bohai Sea. TIN concentration in Laizhou Bay (4.444 ${\mu}$mol$.$l$\^$-1/), for example, was significantly higher than those in Bohai Bay (2.270 ${\mu}$mol$.$l$\^$-1/) and Bohai Straight (2.431 ${\mu}$mol$.$l$\^$-1/), which probably reflects tile discharge of large amounts of nitrogen into Laizhou Bay via Yellow River. The nutrients also showed vertical distribution pattern. In summer, nutrients in bottom layer were generally higher than those in surface and medium layers. In winter, however. nutrients in different layers were not significantly different Compared with historic data, TIN contents increased continuously since early 1980s, phosphorus arid silicone contents, nevertheless, fell down to some degree. Based on atomic ratios of different nutrients, nitrogen is still the main limiting factor for algal growth in Bohai Sea.

• The Journal of Advanced Prosthodontics
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• v.12 no.2
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• pp.100-106
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• 2020

PURPOSE. The purpose of this in vitro study was to evaluate the fitting accuracy of single crowns made from a novel presintered Co-Cr alloy prepared with a computer-aided design and computer-aided manufacturing (CAD/CAM) technique, as compared with crowns manufactured by other digital and the conventional casting technique. Additionally, the influence of oxide layer on the fitting accuracy of specimens was tested. MATERIALS AND METHODS. A total of 40 test specimens made from Co-Cr alloy were investigated according to the fitting accuracy using a replica technique. Four different methods processing different materials were used for the manufacture of the crown copings (milling of presintered (Ceramill Sintron-group_cer_sin) or rigid alloy (Tizian NEM-group_ti_nem), selective laser melting (Ceramill NPL-group_cer_npl), and casting (Girobond NB-group_gir_nb)). The specimens were adapted to a resin model and the outer surfaces were airborne-particle abraded with aluminum oxide. After the veneering process, the fitting accuracy (absolute marginal discrepancy and internal gap) was evaluated by the replica technique in 2 steps, before removing the oxide layer from the intaglio surface of the crowns, and after removing the layer with aluminum oxide airborne-particle abrasion. Statistical analysis was performed by multifactorial analysis of variance (ANOVA) (α=.05). RESULTS. Mean absolute marginal discrepancy ranged between 20 ㎛ (group_cer_npl for specimens of Ceramill NPL) and 43 ㎛ (group_cer_sin for crowns of Ceramill Sintron) with the oxide layer and between 19 ㎛ and 28 ㎛ without the oxide layer. The internal gap varied between 33 ㎛ (group_ti_nem for test samples of Tizian NEM) and 75 ㎛ (group_gir_nb for the base material Girobond NB) with the oxide layer and between 30 ㎛ and 76 ㎛ without the oxide layer. The absolute marginal discrepancy and the internal gap were significantly influenced by the fabrication method used (P<.05). CONCLUSION. Different manufacturing techniques had a significant influence on the fitting accuracy of single crowns made from Co-Cr alloys. However, all tested crowns showed a clinically acceptable absolute marginal discrepancy and internal gap with and without oxide layer and could be recommended under clinical considerations. Especially, the new system Ceramill Sintron showed acceptable values of fitting accuracy so it can be suggested in routine clinical work.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.241-241
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• 2008

Macrofore formation in silicon and other semiconductors using electrochemical etching processes has been, in the last years, a subject of great attention of both theory and practice. Its first reason of concern is new areas of macropore silicone applications arising from microelectromechanical systems processing (MEMS), membrane techniques, solar cells, sensors, photonic crystals, and new technologies like a silicon-on-nothing (SON) technology. Its formation mechanism with a rich variety of controllable microstructures and their many potential applications have been studied extensively recently. Porous silicon is formed by anodic etching of crystalline silicon in hydrofluoric acid. During the etching process holes are required to enable the dissolution of the silicon anode. For p-type silicon, holes are the majority charge carriers, therefore porous silicon can be formed under the action of a positive bias on the silicon anode. For n-type silicon, holes to dissolve silicon is supplied by illuminating n-type silicon with above-band-gap light which allows sufficient generation of holes. To make a desired three-dimensional nano- or micro-structures, pre-structuring the masked surface in KOH solution to form a periodic array of etch pits before electrochemical etching. Due to enhanced electric field, the holes are efficiently collected at the pore tips for etching. The depletion of holes in the space charge region prevents silicon dissolution at the sidewalls, enabling anisotropic etching for the trenches. This is correct theoretical explanation for n-type Si etching. However, there are a few experimental repors in p-type silicon, while a number of theoretical models have been worked out to explain experimental dependence observed. To perform ordered macrofore formaion for p-type silicon, various kinds of mask patterns to make initial KOH etch pits were used. In order to understand the roles played by the kinds of etching solution in the formation of pillar arrays, we have undertaken a systematic study of the solvent effects in mixtures of HF, N-dimethylformamide (DMF), iso-propanol, and mixtures of HF with water on the macrofore structure formation on monocrystalline p-type silicon with a resistivity varying between 10 ~ 0.01 $\Omega$ cm. The etching solution including the iso-propanol produced a best three dimensional pillar structures. The experimental results are discussed on the base of Lehmann's comprehensive model based on SCR width.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.310-316
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• 2012

The chromaticity of polyethylene glycol (PEG) generated from the recyling of a silicone slurry waste was improved by using activated carbon powder and a carbon filter. The color change of the PEG waste was investigated by changing the amount of adsorbent, adsorption time and temperature. The surface area of activated carbon did not have a significant impact on improving the color of the PEG waste. According to the results for the APHA color variation of the PEG waste changing the amount of the carbon adsorbent, the optimal usage to achieve the low APHA value was 100~150 mg-C/g-PEG. From the investigatnion on the effect of the adsorption temperature range from $25^{\circ}C$ to $100^{\circ}C$, it was found that the optimal temperatures were $40{\sim}50^{\circ}C$ in terms of achieving the lowest APHA value. The variation of the APHA color was investigated by changing the operation condition of the activated carbon filters. The use of ACF was a good way to enhance the chromaticity of the PEG waste. As a result, the APHA value of the PEG waste (APHA=53 at the initial waste) was reduced to be 10 through the ACF purification. It was also confirmed that the performance of the used carbon adsorbent can be recovered by the washing with purified water.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.1
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• pp.97-102
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• 2012

A hermetically sealed oil transformer is designed by applying expanding function of the tank due to the volume changes of the insulation oil according to the temperature rises. When the insulation oil expands, an increase in the volume of the corrugated fin prevents a pressure rise of the transformer. For a wind turbine transformer, a vegetable-oil-immersed transformer has the advantages of excellent biodegradation and fire-resistant properties like an exceptionally high fire point. When vegetable oil is substituted for mineral oil, however, the maximum winding temperature rises because of the decrease in the internal circulation flow rate resulting from the variations of the oil's physical characteristics, such as density and viscosity. The purpose of this study is to develop a hermetically sealed vegetable oil transformer that can be applied in a wind turbine and to analyze the thermal stability of the active part of the transformer to deal with pressure variations due to the temperature changes. In addition, thermal tests for the vegetable oil transformer have been performed, and the measured values are compared with the analysis results.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.18 no.1
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• pp.81-98
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• 1992

Hairless mice (Skh:HR-1) exposed to single doses (0.5, 1.0 and 3. OMED) of UV-B radiation were displayed remarkable changes of barrier function and surface morphology. Trans- epidermal water loss (TEWL) as an index of barrier function was measured by evaporimeter, and wrinkle density (WD) as an index of morphological alteration was measured by image analyzer. Significant changes of TEWL were not observed in the control and 0. SMED group, but 1.OMED and 3. OMED groups noted significant difference. TEWL of 3. OMED group was rapidly increased to the 3rd day and decreased until the 14th day when it reached nearly to normal level, Time-courses of TBWL for 1. OMEB and 3. OMED groups displayed similar pattern, but different only in the magnitude. WD were significantly decreased during the 3rd-5th day in all of the irradiated groups and then increased during the last period to the 14th day, but did not recover the normal level at the 14th day. Time-courses of WD for all groups exhibited similarity, and were entirely dependent on the exposed doses. We also observed histological changes which included hyperplasia, sunburn cell (SBC) formation, accumulation of polymorphonuclear leukocyte (PMNs), and loss of collagen of UVB- exposed hairless mouse skin. Changes of TEWL and WD are helpful in understanding of epidermal and dermal damages by single exposure of UVB.

• Journal of dental hygiene science
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• v.14 no.3
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• pp.405-410
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• 2014

The purpose of this study in vitro investigation was to compare the marginal and internal fit of Ni-Cr alloy metal ceramic crown before and after porcelain veneering. Furthermore, this study evaluated whether the influence of the porcelain firing on the precision of fit of dental prostheses. The maxillary right incisor was selected as an abutment for experiments. Ten working models were prepared. Ni-Cr alloy cores appropriate for each abutment were prepared by lost wax technique. The marginal area and four internal areas of the crowns were measured at two stages: before veneering process and after upper porcelain firing. Silicone replica techniques were used. The data were statistically analyzed with the paired t-test (${\alpha}=0.05$). $Mean{\pm}SD$ marginal and internal gap were $67.1{\pm}23.3{\mu}m$ for the nickle chrome alloy core group and $74.4{\pm}21.9{\mu}m$ for the metal ceramic crown group. There were statistically significant differences in all investigated areas (p<0.05). Within the limitations of this study, none of the Ni-Cr alloy metal crown values measured after porcelain firing process exceeded $120{\mu}m$, which is the clinically acceptable threshold.