• International Journal of Aerospace System Engineering
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• v.6 no.1
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• pp.1-7
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• 2019

In the present study, structural safety and stability on the main wing and tail planes of the 1.2 ton WIG(Wing in Ground Effect) flight vehicle, which will be a high speed maritime transportation system for the next generation, was performed. The carbon-epoxy composite material was used in design of wing structure. The skin-spar with skin-stressed structural type was adopted for improvement of lightness and structural stability. As a design procedure for this study, the design load was estimated with maximum flight load. From static strength analysis results using finite element method of the commercial codes. From the stress analysis results of the main wing, it was confirmed that the upper skin structure between the second rib and the third rib was unstable for the buckling load. Therefore in order to solve this problem, three stiffeners at the buckled region were added. After design modification, even though the weight of the wing was a little bit heavier than the target weight, the structural safety and stability was satisfied for design requirements.

• Archives of Plastic Surgery
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• v.41 no.6
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• pp.661-667
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• 2014

Background Tissue expansion is an effective and valuable technique for the reconstruction of large skin lesions and scars. This study aimed to evaluate the applicability and safety of a newly designed skin expanding bioreactor system for maximizing the graft area and minimizing the donor site area. Methods A computer-controlled biaxial skin bioreactor system was used to expand skin in two directions while the culture media was changed daily. The aim was to achieve an expansion speed that enabled the skin to reach twice its original area in two weeks or less. Skin expansion and subsequent grafting were performed for 10 patients, and each patient was followed for 6 months postoperatively for clinical evaluation. Scar evaluation was performed through visual assessment and by using photos. Results The average skin expansion rate was $10.54%{\pm}6.25%$; take rate, $88.89%{\pm}11.39%$; and contraction rate, $4.2%{\pm}2.28%$ after 6 months. Evaluation of the donor and recipient sites by medical specialists resulted in an average score of 3.5 (out of a potential maximum of 5) at 3 months, and 3.9 at 6 months. The average score for patient satisfaction of the donor site was 6.2 (out of a potential maximum of 10), and an average score of 5.2 was noted for the recipient site. Histological examination performed before and after the skin expansion revealed an increase in porosity of the dermal layer. Conclusions This study confirmed the safety and applicability of the in vitro skin bioreactor, and further studies are needed to develop methods for increasing the skin expansion rate.

• Journal of Environmental Health Sciences
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• v.39 no.6
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• pp.505-512
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• 2013

Objectives: Ultraviolet (UV) radiation may cause skin cancer, photo-ageing, erythema, and sunburn. Benzophenone (BP) is commonly used to protect skin from UV radiation. In Korea, sunscreen, sunblock, socalled 'blemish balm' (BB) and 'color correcting' (CC) creams, and foundation may contain from 0.5 to 5% benzophenone in order to protect skin from UV radiation. The purpose of this study is to understand the levels of benzophenone derivatives in urine among a group of university students and identify the contribution of cosmetics use. Methods: Forty volunteers (20 women and 20 men) were asked about skin type, frequency of use of cosmetics, and recognition of related health effects, etc. in a survey. Subjects were divided into several subgroups and were compared for concentration of benzophenone-1 (BP-1) and benzophenone-3 (BP-3). Their urine was pretreated with enzyme hydrolysis and solid phase extraction. Determinations of BP-1 and BP-3 in the urine were made with LC-MS/MS. Results: Among the study subjects, 82.5% used basic cosmetics at least once per day, and 77.5% used sunscreens at least once per day. The concentrations of BP-1 and BP-3 of the males were 4.36 ng/mL and 9.16 ng/mL, respectively. Those of the females were 3.98 ng/mL and 5.07 ng/mL, respectively. The use of cosmetics was positively related to urinary benzophenone levels. Conclusions: BP-1 and BP-3 were widely detected among the university students. Cosmetic use was identified as a potential source. Implications of such exposure deserve further investigation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.32 no.4
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• pp.271-276
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• 2018

The purpose of pilot clinical trial is to evaluate the efficacy and safety of acupuncture therapy on TEWL(Transepidermal Water Loss) and skin hydration. A total of 36 human who visited Dongshin University Oriental Medical Center from October 2nd, 2015 to July 31st, 2016 were included in the pilot clinical trial. Acupuncture therapy was performed at Gokji(LI11) and Daechu(GV14). We observed change of TEWL(Transepidermal Water Loss), skin hydration before and after acupuncture therapy. In the primary endpoint, index of TEWL showed a statistically significant decline($8.01{\pm}2.55{\rightarrow}6.58{\pm}1.97g/h/m2$, $7.40{\pm}2.65{\rightarrow}4.99{\pm}1.89g/h/m2$). Index of skin hydration showed statistical significance($52.83{\pm}6.53{\rightarrow}56.82{\pm}7.24$, $63.50{\pm}8.57{\rightarrow}64.96{\pm}8.48$). To evaluate the safety, vital sign check were conducted and showed no statistically significant result. And there were no severe adverse events during this study. According to the above pilot clinical trial, it is suggested acupuncture therapy were effective for skin moisturizing.

• Toxicological Research
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• v.29 no.2
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• pp.87-90
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• 2013

The potential role of topical valproate (VPA) in hair regrowth has been recently suggested. However, safety reports of VPA as a topical formulation are lacking. Therefore, in the present study, we investigated whether VPA causes skin irritation in humans. We first performed a cell viability test and showed that VPA did not exhibit toxicity toward HaCaT keratinocytes, fibroblasts, and RBL-3H mast cells. We then performed clinical patch test and skin irritation test through transdermal drug delivery with the help of microneedle rollers. No significant findings were obtained in the clinical patch test. In the skin irritation test, only 1 patient showed erythema at 1 hr, but the irritation reaction faded away within a few hours. Erythema and edema were not observed at 24 hr. We concluded that VPA has minimal potential to elicit skin irritation. Therefore, we consider that VPA can safely be applied to human skin.

• Korean Journal of Pharmacognosy
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• v.42 no.1
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• pp.76-81
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• 2011

The study of irritation and toxicity of honeybee(Apis mellifera. L) venom collected by a bee venom collector applied topically to the skin and mucous membrane were carried out to prove the safety of honeybee venom in clinical use. Animal for the research was the rabbit and the solution for the test was made from honeybee venom. Six animals were used for the skin test and nine animals were used for the eye mucous membrane test. In results, both tests proved that honeybee venom makes no irritable reaction on skin and eye mucous membrane of rabbit. We consider that this result is helpful for saying about the safety of honeybee venom in clinical use.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.7 no.2
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• pp.279-288
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• 1997

The penetrating speeds of organic solvents into the nude mouse skin were measured by in vitro methods(diffusion cell methods) and in vivo methods(measuring internal residues of the organic solvents). The results were as follows: 1. The penetrating speeds of toluene, m-xylene, MEK, MIBK, ethanol, IPA and 2-bromopropane into the skin were $0.4832mg/cm^2/h$, $0.1738mg/cm^2/h$, $1.124mg/cm^2/h$, $0.6627mg/cm^2/h$, $1.747mg/cm^2/h$, $1.359mg/cm^2/h$, and 2-bromopropane $4.165mg/cm^2/h$ respectively. 2. The penetrating speeds of the mixtures of two, toluene and m-xylene, the mixture of three, IPA, ethyl acetate, and MIBK, the mixture of five, toluene, m-xylene, IPA, ethyl acetate, and MIBK were $0.172mg/cm^2/h$, $1.431mg/cm^2/h$, and $2.983mg/cm^2/h$ respectively. 3. The absorption speeds of 2-bromopropane and styrene which were measured by in vivo processes were $3.12mg/cm^2/h$ and $1.44mg/cm^2/h$ respectively. The absorption speed of 2-bromopropane mesured in vivo was 74.9% of that measured by in vitro methods, $4.165mg/cm^2/h$.

• Korean Journal of Veterinary Service
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• v.45 no.2
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• pp.133-137
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• 2022

Lumpy skin disease (LSD) is a severe cross-border infectious disease that causes fever, skin and visceral nodules in cattle. LSD is caused by the lumpy skin disease virus (LSDV), a dsDNA virus that belongs to the genus Capripoxvirus. Although LSD has been found only in Southern Africa traditionally, in the last decade it is spreading very quickly through the Middle East and into Eastern Europe and China. It usually affects cattle and water buffalos being transmitted by blood-feeding insects. As it causes a huge economic impact, LSD is a notifiable disease by World Organisation for Animal Health, and managed as the legal infectious disease class I in Korea. Therefore, the purpose of this study was to confirm the existence of LSDV antigens or antibodies in Korean livestock. We collected 1,200 blood samples from cattle (Korean native and dairy cattle) and Korean water deer in 4 major provinces of the country, then tested the existence of LSDV antigen and antibody. None (0.0%) of the 1,200 blood samples were positive for both antigen and antibody of LSDV. To the best of our knowledge, this is the first study that examines the prevalence of LSDV in Korea. Our study aims to report the LSDV occurrence situation obtained by surveillance in Korea and provide information that may help prevention of LSD epidemics.

• Toxicological Research
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• v.28 no.1
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• pp.51-56
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• 2012

A novel synthetic hexapeptide (SFKLRY-$NH_2$) that displays angiogenic activity has been identified by positional scanning of a synthetic peptide combinatorial library (PS-SPCL). This study was carried out to investigate the irritation of the SFKLRY-$NH_2$ on the skin. The tests were performed on the basis of Korea Food and Drug Administration (KFDA) guidelines. In results, cell toxicity is not appeared for SFKLRY-$NH_2$ in HaCaT cells and B16F10 cells. SFKLRY-$NH_2$ induced no skin irritation at low concentration ($10{\mu}m$), mild irritation at high concentration (10mM). We consider that this result is helpful for saying about the safety of SFKLRY-$NH_2$ in clinical use.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.1 s.160
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• pp.119-130
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• 2007

The objects of this study were to investigate responses and peculiarity during local cooling by parts of the human body and to show permissible safety limits without injurious to his health because of excessive cooling when he works hot environments. It were measured rectal temperature, skin temperature, heart rate, total body weight loss, local sweat in back and thigh, clothing microclimate and subjective sensation on 8 subjects and cooling parts were head, neck, chest, abdomen, back, waist, hip, upper arm, forearm, hand, thigh, calf and foot. According to above-mentioned the first experiment, we chose permissible safety limits by parts of the human body for one hour. In the second experiment, it was showed permissible safety limits by parts which examined their safety about health through 4 hours cooling test on 3 subjects. The results are as follows: 1. As a result of the first experiment, we chose permissible safety limits by parts, as follows, head $25^{\circ}C$, neck $20^{\circ}C$, chest $27^{\circ}C$, abdomen $25^{\circ}C$, back $20^{\circ}C$, waist $20^{\circ}C$, upper arm $20^{\circ}C$, forearm $20^{\circ}C$, hand $23^{\circ}C$, thigh $20^{\circ}C$, calf $20^{\circ}C$ and foot $23^{\circ}C$ in $37^{\circ}C$, 50%R.H. environment for 1 hour. 2. As a result of the second experiment, cooling on these safety limits temperatures except chest didn't have a bad effect on health. So it was proved that right permissible safety limits of chest was $28^{\circ}C$. From these results, it has been suggested that skin temperature didn't fall below permissible safety limits when human body was to be cool by parts.