• Polymer(Korea)
• /
• v.34 no.1
• /
• pp.8-13
• /
• 2010

The physical properties of polymeric foams depend on the density of foams, physical properties of base polymers, the content of open cells, and cell structures including the size and its distribution, the shape of cell, and the thickness of skin layer. The foam density is affected by the chemistry of raw materials, the concentration of crosslinking agent and the blowing agent as well as the operating parameters during production process. In this study, the basic formulations of foams are composed of polyester polyol, MDI, amine catalyst, tin catalyst, silicone surfactant, and water. Cross-linking density of polyurethane was increased by using chain extenders. Also, the mechanical properties of polyurethane foam were improved by using the inorganic fillers (silica 1,2 and talc 1,2) having different $SiO_2$ contents and particle sizes. We investigated the properties of modulus, tensile strength, compressive strength and hardness of foams obtained by changing kind of inorganic filler and chain extender, and observed the distribution of inorganic filler as well as variation of cell size within the foams by electron microscopy.

• Membrane Journal
• /
• v.10 no.3
• /
• pp.130-138
• /
• 2000

Polyethersulfone (PES) asymmetric membranes for gas separation were prepared by dry/wet phase inversion method and their separation properties for CO$_2$ and N$_2$ gases were investigated. The effects of important variables such as composition of casting solution and evaporation time in preparation of asymmetric gas membrane on membrane morphology and the separation properties were analyzed and the optimum condition of membrane preparation was established. To compensate the defects like pinholes existed on skin layer of the membrane prepared, the membranes were coated with silicone resin. By comparing separation properties after coating with those before coating, we found that the coating of silicone resin was effective to enhance the separation properties. The casting solution mainly used in this study consisted of PES, N-methyl-2-pyrrolidone, acetone, ethanol and distilled water was used as coagulation agent. It was shown that the selectivity for CO$_2$/N$_2$ was getting higher but the permeability decreases, as the contents of PES and volatile organic solvent and evaporation time increased. The selectivity for CO$_2$/N$_2$ and permeability of CO$_2$ of the membrane prepared under the optimum condition were found to be 61 and 21 GPU, respectively.

• Korean Chemical Engineering Research
• /
• v.43 no.4
• /
• pp.482-486
• /
• 2005

The biodegradable poly(${\varepsilon}$-caprolactone)(PCL)/poly(ethylene imine)(PEI) microcapsules containing $Al_2O_3$ and fragrant oil were prepared with different PEI contents. The effects of stirring rate and concentration of the surfactant on the diameter and morphologies of microcapsules were investigated by using scanning electron microscope (SEM). Thermal behaviors were studied by using a differential scanning calorimetry(DSC), and the release behaviors of fragrant oil from microcapsule were characterized by UV/vis. spectrophotometer. As a result, the average particle size of the microcapsules decreased with increasing the stirring rate or concentration of the surfactant. The surface morphologies of the microcapsules were changed from smooth surfaces to skin-like rough surfaces as increasing the PEI content. These results were mainly due to the increased hydrophilic groups at the microcapsule surfaces, resulting in increasing the release rate of fragrant oil in the microcapsules studied.

• Archives of Plastic Surgery
• /
• v.40 no.2
• /
• pp.91-96
• /
• 2013

Background A thinned anterolateral thigh (ALT) flap is often harvested to achieve optimal skin resurfacing. Several techniques have been described to thin an ALT flap including an adipocutaneous flap, an adipofascial flap and delayed debulking. Methods By systematically reviewing all of the available literature in English and French, the present manuscript attempts to identify the common surgical indications, complications and donor site morbidity of the adipofascial variant of the ALT flap. The studies were identified by performing a systematic search on Medline, Ovid, EMBASE, the Cochrane Database of Systematic Reviews, Current Contents, PubMed, Google, and Google Scholar. Results The study selection process was adapted from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement, and 15 articles were identified using the study inclusion criteria. These articles were then reviewed for author name(s), year of publication, flap dimensions and thickness following defatting, perforator type, type of transfer, complications, thinning technique, number of cases with a particular area of application and donor site morbidity. Conclusions The adipofascial variant of the ALT flap provides tissue to fill large defects and improve pliability. Its strong and safe blood supply permits adequate immediate or delayed debulking without vascular complications. The presence of the deep fascia makes it possible to prevent sagging by suspending and fixing the flap for functional reconstructive purposes (e.g., the intraoral cavity). Donor site morbidity is minimal, and thigh deformities can be reduced through immediate direct closure or liposuction and direct closure. A safe blood supply was confirmed by the rate of secondary flap debulking.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.26 no.1
• /
• pp.1-18
• /
• 2013

Objective: Recently the demands for the effective and safe depigmentative and anti-aging agents of the skin have increased due to the medical, pharmaceutical and cosmetic reasons. The purpose of this study is to investigate the MKG(Methanol Extract of Kaempferia galanga) and their dermal bioactivity properties related to cosmeceuticals such as depigmentation. Methods: We assessed inhibitory effects of MKG on melanin production in B16/F10 melanoma cells, on mushroom tyrosinase activity, effects of MKG on the expression tyrosinase, TRP-1, TRP-2, GSK-$3{\beta}$, CREB, MITF in B16/F10 melanoma cells without cytotoxicity range. Cell viability was measured by MTT assay and tyrosinase activity was assessed using by DOPA staining, western-blot analysis. We measured inhibition of melanin synthesis and tyrosinase activity by down-regulation of melanogenic enzyme expressions in ${\alpha}$-MSH induced melanogenesis B16/F10 melanoma cells. Results: MKG inhibited tyrosinase-activity, total melanin contents and dendrite out-growth. MKG inhibited melanogenesis by down-regulation of tyorsinase, TRP-1, TRP-2, CREB, and MITF in B16/F10 cells. The treatment with MKG at the 12.5, $25{\mu}g/ml$ level significantly inhibited the melanin synthesis induced ${\alpha}$-MSH in B16/F10 melanoma cells compared with untreated control. Conclusion: These results suggest that MKG inhibit melanin biosynthesis which is involved in hyper-pigmentation. So MKG is considered to be used as a whitening components reducing cytotoxicity.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.20 no.1
• /
• pp.228-238
• /
• 1996

The purpose of this study was to evaluate the effect of chacteristics of knit fabrics on the microclimate of the skin simulating system. To determine the effect of characteristics of knit fabrics, vapor state of sweat pulse was simulated in the closed system. Different contents of fibers such as cotton, wool and polyester with different yarn size and knit types were chosen for specimens. The changes of humidity and temperature of air layer in the simulated systems were measured. Buffering indices, $K_d$ and $\beta_r$, were determined by considering $\alpha_p, \DeltaP_{max}, t_{max}, and tan\beta$. Physical properties of knit fabrics such as thickness, porosity, air resistance and moisture vapor transport were measured. Results showed that vapor pressure of wool was lower than cotton or polyester This was attributed to the hydrophilicity of wool which absorbed moisture rather quickly and retained in the knit fabric. The time to decrease vapor pressure was faster for polyester than cotton or wool. As a result, $K_d$ was in the order of wool> polye, item> cotton. $\beta_r$ of wool was rower than cotton or polyester due to its lowers porosity and slower desorption rate. For the yarn size, $K_d$ was in the order of 80's> 60's> 30's; thinner and lighter yarn showed better water vapor transport property. For knit type, buffering capacity of single jersey was better than interlock knit fabric. Statistical analysis showed that the air permeability was the most influential factor far the water vapor transport properties.

• Journal of the Korean housing association
• /
• v.19 no.5
• /
• pp.57-65
• /
• 2008

The purpose of this study is to figure out the relationship between the residence stories in high-rise condominium and residents' disease patterns throughout the dweller's medical reports. Research basic data are obtained from medical fee request of National Health Insurance Corporation. Data are limited to 'A' high-rise condominium and a medical treatment time to 3 years (2004. 1-2006, 12). Data for analysis are composed of total 346,286 medical records, 43,159 disease records, and 8,999 personal records. Data are stored by sex, age, building story, residence story, visiting year and month, treatment days, main disease type (KCD-4). Treatment number, disease type and asthma in disease records and personal records are statistically analyzed by residence story considering age. Findings are as follows: 1) Women have more medical treatments than men, 40-50 age group is more treated, and the residents of 6-25 stories are more received medical treatments. According to KCD-4, diseases of the respiratory system and diseases of the eye and adnexa are relatively treated higher than other diseases. 2) The diseases of he respiratory system, the eye and adnexa, the skin and subcutaneous issue, the ear and mastoid process, and the asthma have not relation to the high-storied residence through the data of disease records and personal records. But the analysis on the data of children, age 7 and less, showed a significant relation. to conclude, there is no relationship between the residence of high-stories in the condominium and residents' disease patterns, but there is a little probable to the relationship in the pre-school child.

• Asian-Australasian Journal of Animal Sciences
• /
• v.16 no.9
• /
• pp.1348-1354
• /
• 2003

The feeding value of high-oil corn fed to Taiwan Country (TC) chicken was examined by measuring apparent metabolizable energy (AME), growth performance, sexual maturity, carcass characteristics, and plasma pigmentation. In a completely randomized design, 870 sex-intermingled one-wk-old chicks were assigned to one of 30 floor pens, 29 birds per pen, and each pen randomly assigned to one of five dietary treatments. The experiment was ended when birds were 16 wk of age. The five dietary treatments varied in main fat sources, which were corn oil (CO), high-oil corn (HOC), lard (LRD), whole soybean (WSB) and yellow corn (YC), respectively. All the diets were formulated isonitrogenously, isocalorically, and of equal lysine and methionine contents except YC, in which equal amounts of YC replaced HOC. The results indicated that feed conversion in HOC was 8% higher (p<0.05) than YC whereas the calculated AME of HOC was only 3.5% to 4.0% higher than that of YC. No significant differences were observed in body weight, body weight gain, feed consumption, feed conversion ratio and ME efficiency for body weight gain among CO, HOC, LRD, and WSB. No significant differences existed in both skin and muscle pigmentation of breast among the five dietary treatments. No significance differences existed in plasma carotenoid content measured at various ages among the five dietary treatments except that birds fed with HOC had less (p<0.05) plasma carotenoids at 16 wk-old. The results indicate that if the price of high-oil corn is no more than 1.05 times that of yellow corn, the dietary cost per kg of body weight gain for TC chickens fed diets containing high-oil corn will be less, although their body weight may be lighter compared to chickens fed diets formulated with other fat sources.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.4
• /
• pp.1875-1879
• /
• 2016

Background: Breast cancer is the most common cancer among women worldwide. A very important factor in the timely treatment and prevention of progression is high breast cancer awareness. Rural women are at risk of latte stage breast cancer due to poor education and lack of access to medical facilities. Materials and Methods: This cross-sectional-descriptive study was conducted on 266 women (out of 300) aged over 18 in rural areas of Zabol, Southeastern Iran during July 2015 to October 2015. The data collection tool was a researcher-made questionnaire that measured participant knowledge of breast cancer in four aspects (general awareness, risk factors, mammography, and symptoms). SPSS 22 was used for statistical analysis. Results: Out of 266 participants, age information was available for 261. The age range was between 19 and 62, with a mean of $27{\pm}2.1years$. Most participants (154, 57.9%) had an average overall awareness of breast cancer. In the general awareness dimension, most participants (130, 48.9%) had poor scores. Most (166, 62.4%) also had average awareness about risk factors and many (137, 51.5%) had good awareness about mammography. Most participants did not know that changes in breast shape (232, 88.2%), dimpling of breast skin (192, 72.3%) and nipple discharge (183, 69.6%) are the main symptoms of breast cancer. ANOVA statistical analysis showed a significant relationship between awareness level and participant education and occupation (P<0.05). Conclusions: This study indicated average awareness of participants about breast cancer. Since rural women have lower levels of education, it is recommended that educational courses with contents about breast cancer, its risk factors, and symptoms be held for these women.

• Korean Journal of Human Ecology
• /
• v.13 no.1
• /
• pp.111-122
• /
• 2004

The purpose of the study lied on supporting the reeducation program which was focused on the demand with the clients by analyzing the recognition on the real situations of the reeducation on the hair designers in the nation. As a result on the subject, the responders said they could usually learn new information through the various seminars that were held by beauty product suppliers and companies, and most of the high school or under high school level designers have participated in various seminars while the designers who graduated from a junior college or universities had experienced new trends at life time education establishments(p<0.01). A hair designer who was single and paid low salary usually depended on the course inside the shop(p<0.01), and most of the information they got was through the suppliers of the beauty products. In that case, regular sources of information, such as educational establishments, informative magazines, Internet were highly recommended. A reason for unsatisfactory reeducation was due to lack of time and a reason for not participating the seminar was also due to time shortage caused by regular working hours, which was reflecting the real situation of the hair designers. As a suggestion for the reeducation establishment, most of the responders wanted vocational schools or life-time educational center. They wanted a fixed regular period for reeducation, especially over the weekend for after working hours. It means they want long-time systematic education. Considering the results, a course which is organized for a long-time systematic purpose is suggested for the hair dressers who want to be professionals in the field with the class equipped with contents of the classes, period, and place. For the purpose to be realized, improvement of the working hours in needed and it will be an incentive to make the hair designers satisfied with their work.