• Proceedings of the Korean Society of Medical Physics Conference
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• 2005.04a
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• pp.35-38
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• 2005

In our country, the skin image and MR Microscopy research has been processed but there were not their outstanding results. So this study start to improve the techniques can get high resolution skin images and to make RF surface coils. Volume coils are sometimes unavailable, or do not provide adequate RF power or SNR for some applications. In high resolution skin and tissue structure images current coils have a technical limitation. It is well known that standard single-loop surface coils, although offering high SNR characteristics, have poor B1 homogeneity. As the RF surface coil need change its geometry we get improved images. So, The magnetic field simulation that is first step to make and design RF surface coil will support reference data.

• Archives of Plastic Surgery
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• v.44 no.4
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• pp.313-318
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• 2017

Background Jeju Island is geographically and socioeconomically distinct from the mainland of South Korea. Thus, the presentation and management of non-melanocytic skin cancers (NMSC) of the head and neck may differ from those in other regions of the country. We compared the clinical characteristics and treatment modalities of NMSC on Jeju Island with the findings of similar regional studies. Methods Patient data, including age, sex, diagnosis, tumor site, treatment, and recurrence, were obtained from the medical and pathology records of patients diagnosed with NMSC between January 2010 and June 2015. Results In total, 190 patients (57 men) with a mean age of 75 years (range, 42-97) were assessed. Overall, 203 NMSCs were diagnosed, including 123 basal cell carcinomas and 80 squamous cell carcinomas. The tumor sites included the nose, cheeks, periorbital area, and lips (n=55, 54, 25, and 20, respectively). We identified 92 T1-stage and 60 T2-stage tumors, and 120 cases were treated with wide surgical resection and 17 cases were treated with radiation therapy at the medical center. Of the 120 cases treated surgically, 69 required reconstructive surgery using a local skin flap, 22 required full-thickness skin grafting, and 12 underwent primary closure. Basal and squamous cell carcinomas recurred in 2 and 1 cases, respectively. Conclusions Compared to the reports from other regions, the average patient age was 10 years higher, with a marked female preponderance. While the proportion of squamous cell carcinoma was higher than in other regions, the tumor distribution and surgical management profiles were similar.

• Journal of the Korean Applied Science and Technology
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• v.28 no.2
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• pp.170-177
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• 2011

Transdermal drug delivery(TDS) offers many important advantages. For instance, it is easy and painless, it protects the active compound from gastric enzymes, and it avoids the hepatic first-pass effect. Also, it is simple to terminate the therapy if any adverse or undesired effect occurs. But skin is a natural barrier, and only a few drugs can penetrate the skin easily and in sufficient quantities to be effective. Therefore, in recent years, numerous studies have been conducted in the area of penetration enhancement. The most commonly used transdermal system is the skin patch using various types of technologies. Compared with other method of dosage, it is possible to use for a long term. It is also possible to stop the drug dosage are stopped if the drug dosage lead to side effect. Polysaccharide, such as xanthan gum and algin were selected as base materials of TDS. Also, these polymers were characterized in terms of enhancers and drug contents. Among these polysaccharide, the permeation rate of Paroxetine such as lipophilic drug was the fastest in xanthan gum matrix in vitro. We used glycerin, PEG400 and PEG800 as enhancers. Since dermis has more water content(hydration) than the stratum corneum, skin permeation rate at steady state was highly influenced when PEG400 was more effective for lipophilic drug. Proper selection of the polymeric materials which resemble and enhance properties of the delivering drug was found to be important in controlling the skin permeation rate.

• Journal of the Korean Applied Science and Technology
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• v.27 no.4
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• pp.407-414
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• 2010

New biological treatments were being developed at a record place, but their potential could be compromised by a significant obstacle: the delivery of these drugs into a body. Pharmaceutical delivery is now nearly as important as product. New systems are being developed, and Drug Delivery Markets Series cover these new systems. Transdermal Delivery System(TDS) is often used as a method of drug dosage into the epidermic skin. An approach used to delivery drugs through the skin for therapeutic use as an alternative to oral, intravascular, subcutaneous and transmucosal routes. Various transdermal drug delivery technologies are described including the use of suitable formulations, carriers and penetration enhancers. The most commonly used transdermal system is the skin patch using various types of technologies. Compared with other methods of dosage, it is possible to use for a long term. It is also possible to stop the drug dosage are stopped if the drug dosage lead to side effect. Polysaccharides, such as karaya gum and glucomannan, were selected as base materials of TDS. Also, these polymers were characterized in terms of enhancers, drug contents. Among these polysaccharide, the permeation rate of karaya gum matrix was fastest in fibric acid(ciprofibrate) such as lipophilic drug in vitro. We used glycerin, PEG400 and PEG800 as enhancers. Since dermis has more water content(hydration) than the stratum corneum, skin permeation rate at steady state was highly influenced when PEG400 was more effective for lipophilic drug. Proper selection of the polymeric materials which resemble and enhance properties of the delivering drug was found to be important in controlling the skin permeation rate. Especially, this result suggests a possible use of polysaccharide gel ointment matrix as a transdermal delivery system of anti-hyperlipoproteinemic agent.

• Korean Journal of Agricultural Science
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• v.24 no.2
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• pp.290-297
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• 1997

Danored is considered as the most favorable grape variety for national wine manufacturing in terms of sugar, organic acid contents, annual production amount, as well as quality control convenience after harvest. This study was canied out to know the influence of suspended solid(SS) and skin contact time(SCT) with Danored variety on the white wine quality. The results are summarized as follows; 1. Suspended solid and skin contact time did not greatly influence on the chemical composition of Danored juice. But skin contact time provided slightly increaseness to the content of phenol compounds 2. Suspended solid accelerated fermentation rate of white wine manufacturing. Although the content of suspended solid are less amount than 0.3% in must, wine fermentation was completed to dryness in concentration of sugar. 3. When the content of suspended solid was around 3%, higher alcohol in white wine was increased by the 20%. This result is relatively small increasement compared to the other reported results. 4. Because Danored contained less amount of phenol compounds comparison with other grape varieties, browning capacity in white wine was much favorable to quite low concentration. Especially, phenolic compounds was decreased remarkably as one of fermentation characteristics of Danored variety. 5. As a result of sensory evaluation, wine quality was A-1> B-1> A-2> B-2 in its favorable ranking orders. It was so concluded that A-1 might be the most acceptable one from this study.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.5
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• pp.667-671
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• 1999

The purpose of this study was to determine the number of skin cold receptor in Korean adult as a part of the study to investigate thermal physiological characteristics of Korean. For this 10 healthy subjects were placed in a climatic chamber and received cold stimulation of 1$0^{\circ}C$ on skin surface of each measuring site with a thermo-stimulator. As a result of cold spot measurement we found 23 points/cm2 at face 13. points/cm2 at chest 16 points/cm2 at abdomen 11 points/cm2 at back 14 points/cm2 at upper arm 16 points/cm2 at forearm 18 points/cm2 at back of the hand 15 points/cm2 at thigh 8 points/cm2 at leg 12 points/cm2 at dorsum of foot 8 points/cm2 at sole of foot in male subjects and in female subjects we fund 18 points/cm2 at face 13 points/cm2 at forearm 11 points/cm2 at at back of the hand 8 points/cm2 at palm 9 points/cm2 at thigh 6 points/cm2 at leg 8 points/cm2 at dorsum of foot 2 points/cm2 at sole of foot. The distributions of cold spots varied in different regions of the body surface and was exceptionally dense in the facial skin. There were some differences among other researchers' results but the cause of those differences are not yet known those are due to individual or methodological difference.

• Journal of Biomedical Engineering Research
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• v.29 no.1
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• pp.59-65
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• 2008

Nowadays, implantable hearing aids have been developed to solve the problems of conventional hearing aids. In case of fully implantable hearing aids, an implantable microphone is necessary to receive sound signal beneath the skin. Normally, an implantable microphone has poor frequency response characteristics in high frequency bands of acoustic signal due to the high frequency attenuation effect of skin after implantation to human body. In this paper, the implantable microphone is designed to reduce the high frequency attenuation effect of a skin by putting its resonance frequency at the attenuated range through a finite element analysis (FEA) simulation. The designed implantable microphone through the simulated results has been fabricated by manufacturing process using bio-compatible materials. By the several in-vitro experiments with pig skin, it has been verified that the designed implantable microphone has a resonance frequency around the starting part of the attenuated range and reduces the attenuation effect.

• Journal of Ginseng Research
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• v.48 no.2
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• pp.211-219
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• 2024

Background: Recently, plant-derived exosome-like nanoparticles (PDENs) have been isolated, and active research was focusing on understanding their properties and functions. In this study, the characteristics and molecular properties of ginseng root-derived exosome-like nanoparticles (GrDENs) were examined in terms of skin protection. Methods: HPLC-MS protocols were used to analyze the ginsenoside contents in GrDENs. To investigate the beneficial effect of GrDENs on skin, HaCaT cells were pre-treated with GrDENs (0-2 × 10⁹ particles/mL), and followed by UVB irradiation or H₂O₂ exposure. In addition, the antioxidant activity of GrDENs was measured using a fluorescence microscope or flow cytometry. Finally, molecular mechanisms were examined with immunoblotting analysis. Results: GrDENs contained detectable levels of ginsenosides (Re, Rg1, Rb1, Rf, Rg2 (S), Gyp17, Rd, C-Mc1, C-O, and F2). In UVB-irradiated HaCaT cells, GrDENs protected cells from death and reduced ROS production. GrDENs downregulated the mRNA expression of proapoptotic genes, including BAX, caspase-1, -3, -6, -7, and -8 and the ratio of cleaved caspase-8, -9, and -3 in a dose-dependent manner. In addition, GrDENs reduced the mRNA levels of aging-related genes (MMP2 and 3), proinflammatory genes (COX-2 and IL-6), and cellular senescence biomarker p21, possibly by suppressing activator protein-1 signaling. Conclusions: This study demonstrates the protective effects of GrDENs against skin damage caused by UV and oxidative stress, providing new insights into beneficial uses of ginseng. In particular, our results suggest GrDENs as a potential active ingredient in cosmeceuticals to promote skin health.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.1
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• pp.45-57
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• 2015

Objectives: This study aims to compare the physicochemical characteristics, toxicological data with Occupational Exposure Limits (OELs) of chemicals under the Occupational Safety and Health Act(OSHA) regulated by the Ministry of Employment and Labor of Korea. Methods: Information on chemicals which have OELs on physicochemical characteristics and toxicological data was collected using Material Safety Data Sheet(MSDS) from Korea Occupational Safety and Health Agency(KOSHA) and the Korea Information System for Chemical Safety Management(KISChem) in 2014. Statistical analyses including correlation and simple regression were performed to compare the OELs with chemical characteristics including molecular weight, boiling point, odor threshold, vapor pressure, vapor density, solubility and octanol-water partition coefficient(OWPC) and toxicological data such as median lethal dose($LD_{50}$) and median lethal concentration($LC_{50}$). Results: A total of 656 chemicals have OELs under OSHA in Korea. The numbers of chemicals which have eight-hour time weighted average(TWA) and short term exposure limits(STEL) are 618 and 190, respectively. TWA was significantly correlated with boiling point and STEL was only correlated with vapor pressure among physicochemical characteristics. Solubility and OWPC between "skin" and "no skin" substances which indicate skin penetration were not significantly different. Both $LD_{50}$ and $LC_{50}$ were correlated with TWA, while the $LC_{50}$ was not with STEL. As health indicators, health rating and Emergency Response Planning Guidelines(ERPG) rating as recommended by the National Fire Protection Association(NFPA) and American Industrial Hygiene Association(AIHA) were associated with OELs and reflect the chemical hazards. Conclusions: We found relationships between OEL and chemical information including physicochemical characteristics and toxicological data. The study has an important meaning for understanding present regulatory OELs.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.46 no.3
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• pp.107-115
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• 2009

Skin color detection is used to classify input pixels into skin and non skin area, and it requires the classifier to have a high classification rate. In previous work, most classifiers used single color model for skin color detection. However the classification rate can be increased by using more than one color model due to the various characteristics of skin color distribution in different color models, and the MLP is also invested as a more efficient classifier with less parameters than other classifiers. But the input dimension and required parameters of MLP will be increased when using two color models in skin color detection, as a result, the increased parameters will cause the huge teaming time in MLP. In this paper, we propose a MLP based classifier with less parameters in two color models. The proposed partially connected MLP based on two color models can reduce the number of weights and improve the classification rate. Because the characteristic of different color model can be learned in different partial networks. As the experimental results, we obtained 91.8% classification rate when testing various images in RGB and CbCr models.