• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.33 no.4
• /
• pp.227-230
• /
• 2007

The multi-lamellar and liquid crystal structures have drawn great public attention in the functional cosmetic and skin-related medicinal areas recently. The structure of an emulsion containing aqueous phase as a binding water and fixed oil phase components forming an association compound of the multi-lamellar structure can reconstruct the intercellular lipid lamellar structure in the stratum corneum and restore barrier function of the skin. In this study, we investigated the beneficial effect of bio-mimic liquid crystal emulsions (BLCE) containing higher fatty alcohol, lecithin, and cholesterol on the skin barrier function, and evaluated its cytotoxicity.

• Composites Research
• /
• v.16 no.4
• /
• pp.59-65
• /
• 2003

FEM analysis of the smart skin structure, and application of the sandwich structures investigated. The honeycomb manufactures only provide stillness of thickness direction and transverse shear modulus. Although these are dominant mechanical properties. the other mechanical properties are needed in FEM analysis. Hence, this work shows procedures of obtaining those mechanical properties. Honeycomb material was assumed to be ar, isotropic material and properties are estimated by its dominant honeycomb properties. The other honeycomb properties are then obtained by mechanical properties of Nomex. Buckling test and three point bending test were simulated by ABAQUS. Both the shell and solid element models were used. The results were compared with experimental results and analytical approaches. They showed good agreements. This study shows a guideline of FEM analysis of smart skin structure using commercial a FEM package.

• International Journal of High-Rise Buildings
• /
• v.7 no.1
• /
• pp.17-32
• /
• 2018

This paper explores the function of a structural skin with an embossed surface applicable to use for tall building structures. The major diagrid system with a secondary embossed surface structure provides an enhanced perimeter structural system by increasing tube section areas and reduces aerodynamic loads by disorienting major organized structure of winds. A parametric study used to investigate an optimized configuration of the embossed structure revealed that the embossed structure has a structural advantage in stiffening the structure, reducing lateral drift to 90% compared to a non-embossed diagrid baseline model, and results of wind load analysis using computational fluid dynamics, demonstrated the proposed embossed system can reduce. The resulting undulating embossed skin geometry presents both opportunities for incorporating versatile interior environments as well as unique challenges for daylighting and thermal control of the envelope. Solar and thermal control requires multiple daylighting solutions to address each local façade surface condition in order to reduce energy loads and meet occupant comfort standards. These findings illustrate that although more complex in geometry, architects and engineers can produce tall buildings that have less impact on our environment by utilizing structural forms that reduce structural steel needed for stiffening, thus reducing embodied $CO^2$, while positively affecting indoor quality and energy performance, all possible while creating a unique urban iconography derived from the performance of building skin.

• Tribology and Lubricants
• /
• v.29 no.5
• /
• pp.304-309
• /
• 2013

Shark skin has functionalities such as self-cleaning and antifouling; it also exhibits excellent drag reduction owing to a hierarchical structure of microgrooves and nanometer-long chain mucus drag reduction interfaces around the shark body. In this study, the wettability of a shark skin surface and its replicas are evaluated. First, a shark skin template is taken from a real shark. Then, shark skin replicas are produced directly from a shark skin template, using a micromolding technique. The quantitative replication precision of the shark skin replicas is evaluated by comparing the geometry of the shark skin template to the replica using 2D surface profiles. Contact angles at the solid-air-water interfaces are evaluated for the shark skin template and its replicas under two conditions: with and without hydrophobic coating. The results show that the microriblets on shark skin improve the hydrophobic feature and play a critical role in self-cleaning.

• Proceedings of the SCSK Conference
• /
• 2003.09a
• /
• pp.387-412
• /
• 2003

Influence of gelatinase on basement membrane (BM) structure was investigated by using a skin equivalent (SE) model. The results showed that (1) gelatinase produced by cells degraded the BM and (2) the addition of matrix metalloproteinase-specific inhibitor to the SE medium accelerated the formation of BM structure, indicating that gelatinase is involved in BM impairment. The activity of gelatinase was also studied in healthy human facial skin tissues. The result of in situ zymography revealed gelatinase activity around the basal layer of the epidermis, where BM integrity was severely compromised. Therefore, this enzyme was suggested to be associated with BM decomposition in human facial skin. To assess the behavior of gelatinase in stratum corneum (SC) non-invasively, an immunological study was performed. Since positive immunostaining of pro-gelatinase B was observed in SC stripped from sun-exposed skin, whereas no positive staining detected in SC of non-irradiated skin, gelatinase in the epidermis could be non-invasively detected by measuring gelatinase in SC. Gelatinase in SC of healthy female volunteers was monitored using a special film that sensitively and conveniently detects gelatinase. Ninetr percent of SC from facial skin (l00 women, 40's-50's) was gelatinase-positive. On the other hand, SC from non-irradiated skin was negative. These results strongly suggest that (1) gelatinase is constantly produced in the facial epidermis of most middle-aged woman during their daily life, and (2) the enzyme might be involved in the aging-related degeneration of both BM and the matrix fibers of the upper layer of the dermis, acting as a very important aging factor. Strong inhibitory activity against gelatinase was found in turmeric extract and identified curcumin as the major ingredient. Topical application of cream containing turmeric extract significantly decreased the number of gelatinase-positive SC clusters in human facial skins. These results indicated that turmeric is an effective ingredient to prevent skin from photo aging by suppressing chlonically upregulated gelatinase activity by UV and to improve skin condition.

• The Research Journal of the Costume Culture
• /
• v.21 no.5
• /
• pp.629-638
• /
• 2013

The purpose of this study is to predict skincare behavior from the perspective of theories about planned behaviors and a systematic structure for identifying influences on human behavior; Consequently, this study attempted to undertake a concrete analysis of influences on skin care behavior. The results showed that: an attempt was made to analyze structural equation modeling as to whether or not to apply Ajzen's theory of planned behavior to skin care behavior. This study found the possibility that the theory of planned behavior might be applicabled to the research model composed of skin care attitude, the norms of skin care, behavioral control on skin care, behavioral intentions of skin care, and skin care behavior at the appropriate level in their entirety. This study found that external control factors of skin care behavior had the highest effect on skin care behavior among other factors.

• Animal cells and systems
• /
• v.11 no.2
• /
• pp.155-160
• /
• 2007

The skin of the Korean bullheads, Pseudobagrus brevicorpus and P. koreanus, is composed of epidermis, dermis and subcutis. The epidermis has three layers, the outermost layer, middle layer and stratum germinativum. The epidermis consists of two types of gland cells, an unicellular mucous cell of sulfomucin and a large club cell having sometimes two nuclei. The epidermis has numerous intraepithelial blood vessels in P. brevicorpus but not at all in P. koreanus. Lymphatic spaces containing lymphocytes are well developed in mainly the stratum germinativum. The dermis lacks scales and consists mostly of bundles of coarse collagen fibers. The collagen bundles are arranged in parallel to each other in the dorsum and lateral region toward the dorsum, but vertically at intervals in the abdomen and lateral region toward the abdomen. Considering this unique skin structure, the two species are likely to exercise cutaneous respiration as a dual respiratory system to overcome hypoxic conditions which frequently occurs in their habitats.

• Korean Journal of Ichthyology
• /
• v.12 no.1
• /
• pp.25-32
• /
• 2000

The structure of skin was studied in Iksookimia longicorpus based on the micro-anatomical investigation of skin fragments taken from four regions. The epidermis was distinguished by two types of skin glands, a small mucous cell and a large club cell. The mucous cell was acid sulfomucins (some sialomueins) but the club cell did not give any histochemical tests for mucosubstances. The presence of a well defined lymphatic system with small lymphocytes was established in the stratum germinativum layer of the epidermis. A large number of blood capillaries run very close to each other just below the basement membrane, and a definite area giving AB and PAS positive was present between the basement membrane and scale.

• Journal of fish pathology
• /
• v.5 no.2
• /
• pp.159-164
• /
• 1992

The skin of fishes is also the important external barrier against a variety of the environmental detrimental agents, allowing normal internal physiological function, so its condition is very important in many disease processes. Since fishes are aquatic, morphologically and physiologically they posses specific characteristics lacking in terrestial animals. Thus, it is necessary to keep in mind various specific histologic characteristics for a precise interpretation of the histopathological lesions. In the normal environment the fish skin is more subtly adapted for its physiological requirements as a limiting barrier than the skin of higher terrestial vertebrates. However, its delicacy makes it high vulnerable to damage in fish culture facilities or polluted waters. Although changes in the skin of fish such as discoloration, ulcerative lesions, are the the most readily observed clinical features of fish, there is a wide variety of possible responses, which are best considered in terms of their site within the skin. Up to now, there are relatively few sytematically described information on the histological structure of the teleost skin as well as integrated reviews of the range of pathological processes that can occur in teleost skin. Therefore it was tried in this article to rearrange the information already described by other investigators on the histological structure and histopathological changes of teleost skin.

• Animal cells and systems
• /
• v.4 no.4
• /
• pp.315-318
• /
• 2000

Structure of the skin in amphibious fish, Periophthalmus modestus, was described in relation to cutaneous respiration. The epidermis has no gland cell. The epidermis consists of three regions: outermost layer of one to five layers of flattened epithelial cells, middle layer of swollen epithelial cells instead of glandular cells and stratum germinativum of cuboidal cells. There are numerous blood capillaries in the outermost layer of the epidermis and diffusion distance between the blood of capillaries and the epidermis is about 1.4 Um. The middle layer of the epidermis appears to be a web-like structure due to the swollen epithelial cells. The stratum germinativum has a well-developed lymphatic space containing lymphocytes. There are numerous blood capillaries and elliptical area with acid mucopolysaccharides in stratum laxum of the dermis. The skin of Periophthalmus modestus may be an accessory respiratory organ for oxygen uptake during terrestrial or aquatic life.