• Journal of Pharmaceutical Investigation
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• v.25 no.2
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• pp.129-136
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• 1995

In order to reduce the systemic side effects and the gastrointestinal irritation of indomethacin following its oral administration, the drug was formulated as a transdermal gel using poloxamer 407. In vitro diffusion cells fitted with excised rat skins were used to evaluate the effects of formulation variables on skin permeation of indomethacin from poloxamer gels. The formulation variables were the concentrations of indomethacin, poloxamer 407 and ethanol, and the gel pH. The increase of the drug amount in the gel from 0.5% to 2.0% induced a direct but nonlinear increase in the skin permeation rate of indomethacin. The increase of poloxamer concentration from 17.5% to 25% in the gel resulted in a decrease of skin permeation rate of indomethacin, which was due to a reduction in the amount of free drug molecules available for permeation through skin by entrapping more drug molecules within the micelles formed by poloxamer. The increase of ethanol concentration from 10% to 20% in the gel resulted in a linear increase of permeation rate of indomethacin through skin, possibly due to the penetration enhancing effect of ethanol. The skin permeation of indomethacin was substantially influenced by the gel pH, exhibiting a maximum at pH 4.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.8
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• pp.627-635
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• 2012

This study aims at developing an artificial neural network(ANN)-based predictive and adaptive temperature control method to control the openings at internal and external skins, and heating systems used in a building with double skin envelope. Based on the predicted indoor temperature, the control logic determined opening conditions of air inlets and outlets, and the operation of the heating systems. The optimization process of the initial ANN model was conducted to determine the optimal structure and learning methods followed by the performance tests by the comparison with the actual data measured from the existing double skin envelope. The analysis proved the prediction accuracy and the adaptability of the ANN model in terms of Root Mean Square and Mean Square Errors. The analysis results implied that the proposed ANN-based temperature control logic had potentials to be applied for the temperature control in the double skin envelope buildings.

• Structural Engineering and Mechanics
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• v.5 no.4
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• pp.355-368
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• 1997

Fiber reinforced plastic (FRP) rods are used as reinforcement (prestressed or not) to concrete. FRP composites can also be combined with steel to form hybrid reinforcing rods that take advantage of the properties of both materials. In order to effectively utilize these rods, their bond behavior with concrete must be understood. The objective of this study is to characterize and model the bond behavior of hybrid FRP rods made with epoxy-impregnated aramid or poly-vinyl alcohol FRP skins directly braided onto a steel core. The model closely examines the split failure of the concrete by quantifying the relationship between slip of the rods resulting transverse stress field in concrete. The model is used to derive coefficients of friction for these rods and, from these, their development length requirements. More testing is needed to confirm this model, but in the interim, it may serve as a design aide, allowing intelligent decisions regarding concrete cover and development length. As such, this model has helped to explain and predict some experimental data from concentric pull-out tests of hybrid FRP rods.

• Structural Engineering and Mechanics
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• v.5 no.4
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• pp.339-353
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• 1997

Fiber reinforced plastic (FRP) rods provide certain benefits over steel as concrete reinforcement, such as corrosion resistance, magnetic and electrical insulation, light weight, and high strength. FRP composites can be combined with a steel core to form hybrid reinforcing rods that take advantage of properties of both materials. The objective of this study was to characterize the bond behavior of hybrid FRP rods made with braided epoxy-impregnated aramid or poly-vinyl alcohol FRP skins. Eleven rod types were tested using two concrete strengths. Specific topics examined were bond strength, slip, and type of failure in concentric pull-out tests from concrete cubes. From analysis of identical pull-out tests on both hybrid and steel rods, information on relative bond strength and behavior were obtained. It is concluded that strength is similar but slip in hybrid rods is much higher. Hybrid rods failed either by pull-out or splitting the concrete block (with or without yielding of the steel core). Experimental data showed consistency with similar test results presented in the literature.

• Environmental Mutagens and Carcinogens
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• v.25 no.2
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• pp.66-70
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• 2005

Telomerase, a specialized RNA-directed DNA polymerase that extends telomeres of eukaryotic chromosomes, has activity in most malignant tumors and provides a mechanism for the unlimited potential for division of neoplastic cells. Although telomerase is known to be a regulated enzyme, the factors and mechanisms involved in telomerase regulation are not well understood. In the present study, we compared the effect of 12-O­tetradecanoyl-phorbol-13-acetate (TPA) and non-phorbol ester tumor promoters such as okadaic acid, anthralin and benzoyl peroxide on the expression of telomerase in the mouse skin carcinogenesis system, a well characterized model for studying pre-malignant and malignant progression. We found that most early papillomas harvested after 10 weeks of TPA promotion showed telomerase activity. Other papillomas harvested after 10 weeks of okadaic acid, anthralin and benzoyl peroxide promotion and after single treatment of DMBA only also showed telomerase activity, respectively. On the other hand, normal and all skins surrounded by papillomas harvested after 10 weeks of these promoters has no telomerase activity. Taken together these results, there appears to be no clear association between the level of telomerase activity and protein phosphorylation in mouse skin papillomas and telomerase may be useful as bio-markers in early detection of tumors.

• KIEAE Journal
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• v.9 no.2
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• pp.73-80
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• 2009

In the early twentieth century, many architects still practised eclectic design elements. Emergence of new building materials such as steel, concrete and glass were not yet found fresh roles in architectural design. It was Brussels that the use of modern materials gave rise to their new forms and gave influence to not only building skins but also spatial organization. Art Nouveau architecture is often seen as revolutionary and pioneering modern architecture against eclectic classicism prevalent in the 18th and 19th centuries. Despite the fact that some scholars point out that Art Nouveau is more a transient phenomenon than modern architecture proper, no one would deny that Art Nouveau carries a good deal of modern characteristics. This paper intends to show rather ambivalent perspectives upon Art Nouveau architecture. Although it insinuates overly dynamic nature in architectural languages, it does not hamper us from reading Art Nouveau as a vital component of modern architecture. Through a careful analysis of the early domestic designs of Victor Horta, it becomes evident that his work can provide modern architecture a meaningful alibi for its growth. Victor Horta's house design is well known to the public, both for his classical tastes and for its changing implementation. Horta's modern quality is never adequately recognized, partly due to his eye catching modern iron properties and sinuous ornamentation. This paper tries to offer an insight into the complicated stage set of the fin-de-$si{\grave{e}}cle$ through the work of Victor Horta whose influence has been immense in the making of modern architecture.

• KSBB Journal
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• v.32 no.3
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• pp.174-178
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• 2017

Fungal mycelium-based composite materials (FMBC) are a new biomaterial to replace the existing composite materials. To compete with lightweight, high-performance composite materials represented by fiber-reinforced plastic (FRP), various physical and chemical properties and functionality must be secured. Especially, the composite materials made by using mycelium of mushroom is called mushroom plastic. Currently, Ecovative, Grado Zero Espace and MycoWorks in USA and Europe are launching new products. Products utilizing FMBC can be launched in the market for construction materials, automobile interior materials and artificial leather substitutes. In spite of this high possibility, mass production using FMBC has not yet been reported. This review introduces the FMBC, a material that can replace existing plastics, inorganic building materials and animal skins in an environmentally and economically viable way, and looks at the possibility of future biomaterials by summarizing recent research contents.

• Archives of Plastic Surgery
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• v.32 no.3
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• pp.357-362
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• 2005

The aim of this study is to elucidate the effect of keratinase on epidermis of rat skin. Twenty-five male Sprague-Dolly rats were used. The hair on the back were removed and $2{\times}2cm$ area was marked. The rats were divided five groups; 1) Control group(Co), 2) Cleansing gel group(Cl), 3) Cleansing gel+keratinase group, 4) Exfoliant gel group(Ex), and 5) Exfoliant gel+ keratinase group(Ex+K). The solutions were applied to the back area twice a day for five days. On fifth day, the skins were harvested, fixed and prepared for histologic sections. The thickness of keratin layer, living epidermis, dermis, and cell layer number of living epidermis were measured. In the group containing keratinase(Cl+K, Ex+K), the thickness of keratin layer and living layer were thinner than other groups. However, there were no significant differences of the cell layer number of living epidermis and thickness of the dermis among the five groups. We think the keratinase may have the effect thinning the keratin layer as well as the thickness of living epidermis, without effecting the living cell and dermal component. The keratinase containing soap may be of benefit to remove the excess keratin layers in human.

• Steel and Composite Structures
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• v.27 no.3
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• pp.371-388
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• 2018

In this paper, a new model based on nonlocal high order theory is proposed to study the size effect on the bending of nano-sandwich beams with a compliance core. In this model, in contrast to most of the available sandwich theories, no prior assumptions are made with respect to the displacement field in the core. Herein the displacement and the stress fields of the core are obtained through an elasticity solution. Equations of motion and boundary conditions for nano-sandwich beam are derived by using Hamilton's principle and an analytical solution is presented for simply supported nano-sandwich beam. The results are validated with previous studies in the literature. These results can be utilized in the study of nano-sensors and nano-actuators. The effect of nonlocal parameter, Young's modulus of the core and aspect ratio on the deflection of the nano-sandwich beam is investigated. It is concluded that by including the small-scale effects, the deflection of the skins is increased and by increasing the nonlocal parameter, the influence of small-scale effects on the deflections is increased.

• Biomolecules & Therapeutics
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• v.4 no.1
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• pp.36-45
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• 1996

The antihistaminic action of eighteen herbal medicines was investigated by the radioligand binding and functional assays. The hexane fractions of Trichosanthis radix, Mori cortex radicis and Evodiae fructus dosedependently inhibited [$^3$H] mepyramine binding to H$_1$, receptor in guinea-pig brain homogenates and histamine-induced contraction of isolated guinea-pig ileum. Antihistaminic action of the hexane and ethyl acetate fractions of Mori cortex radicis and the hexane fraction of Evodiae fructus was more potent than their antimuscarinic action evaluated from the inhibition of [$^3$H]QNB binding and carbachol response. The ethyl acetate and chloroform fractions from Scutellariae radix also inhibited histamine-induced contraction, but antihistaminic potencies of these fractions were almost identical with their antimuscarinic potencies. The hexane fractions of Mori cortex radicis and Evodiae fructus inhibited selectively the increase of histamine-induced cutaneous vascular Permeability in the rat dorsal skins. However, the ethyl acetate fraction from Scutellariae radix inhibited eqipotently the effects of histamine and serotonin on the vascular permeability. These results demonstrate that the hexane and ethyl acetate fractions of Mori cortex radicis and the hexane fraction of Evodiae fructus have the selective histamine H$_1$receptor blocking activity.