• Journal of Pharmacopuncture
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• v.18 no.3
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• pp.75-79
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• 2015

Objectives: As the peripheral part of the primo vascular system (PVS) is difficult to visualize, we used a vascular casting material Mercox injected directly into the skin to take advantage of a simple procedure to visualize PVS structures as primo vessels (PVs) and primo nodes (PNs) in the skin. Methods: Two colors of the polymer Mercox were injected into mouse skin. After a partial maceration of the whole body with potassium hydroperoxide solution, we anatomized it under a stereomicroscope to trace the Mercox that had been injected into the PVS. Results: Injection of Mercox directly into the skin allowed the PVs and the PNs to be visualized. This approach can fill the PVS when the material is ejected out of the PVs or PNs. The shapes, sizes, and topographic positions of the nodes and the vessels are the hallmarks used to identify the PVS in skin when Mercox is used as a tracer. Conclusion: The direct injection of the casting material Mercox into skin, with modified partial maceration procedures, is a promising method for visualizing the PVs and the PNs in the peripheral part of the PVS in skin. The polymer Mercox can penetrate through the primo pores of the primo vascular wall and fill the PVs and the PNs. The data prove that PVs and PNs exist on the hypodermal layer of the skin.

• Applied Chemistry for Engineering
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• v.19 no.6
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• pp.633-639
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• 2008

Polysulfone membranes were prepared via the phase inversion process. Toluene was added as a nonsolvent additive in the casting solution containing a mixture of polysulfone and n-methylpyrrolidone. When prepared via the diffusion-induced process using isopropanol as a precipitation nonsolvent, the solidified membranes revealed a similar asymmetric structure irrespective of the addition of toluene, presenting both a dense skin layer and a sponge-like support layer. The added toluene played a role of enhancing liquid-liquid phase separation of the casting solution, and skin layer thickness of a prepared membrane increased with toluene content in the casting solution. On membrane performance, the solute rejection showed a uniform behavior irrespective of the addition of toluene. However, in spite of the significant increase in dense skin layer thickness, the water permeation through the membrane prepared with 60 wt% toluene revealed five times as much flux, compared with that of the membrane prepared without toluene additive.

• Journal of Pharmaceutical Investigation
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• v.28 no.1
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• pp.1-5
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• 1998

The effect of synthetic polymer membranes on the permeation rate of dideoxynucleoside-type anti-HIV drugs through hairless rat skin was studied using ethylene/vinyl acetate copolymer (EVA) and ethylene/methyl acrylate copolymer (EMA) membranes fabricated by solvent casting method. In vitro skin permeation kinetics study of DDC (2',3'-dideoxythymidine), DDI (2',3'-dideoxyinosine) and AZT (3'-azido-3'-deoxythymidine) across the (membrane/skin) composite was conducted for 24 hours at $37^{\circ}C$ using the Valia-Chien skin permeation system. The results showed that skin permeation rate of each drug across the (skin/membrane) composite was mainly dependent on the property of the membrane. Proper selection of the polymeric membrane which resembles hydrophilicity/lipophilicity of the delivering drug was important in controlling the skin permeation rate.

• KEPCO Journal on Electric Power and Energy
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• v.7 no.2
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• pp.237-240
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• 2021

Failure of a suspension clamp made of hot dip galvanized cast iron in 154kV transmission tower was investigated. Metallurgical analysis of a crack of the clamp was performed using a digital microscope, an optical microscope, and a scanning electron microscope. It was revealed that the crack surface was covered by continuous zinc layer. Distinctive casting skin was found underneath both the outer surface and crack surface. The result showed that pre-existing crack had been formed in the fabrication, and liquid metal embrittlement during hot dip galvanization may assist crack propagation.

• Membrane Journal
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• v.24 no.1
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• pp.50-62
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• 2014

An asymmetric microfiltration membranes were prepared with polysulfone by an immersion precipitation phase inversion method. Microfiltration membranes were prepared by polysulfone/N-methyl-2-pyrrolidone/polyvinylpyrrolidone/phosphoric acid casting solution and water coagulant. The vapor induced phase inversion method was used to prepare the membranes. The pore size and the morphology were changed by the phosphoric acid additive, the temperature of casting plate and the exposure time at the relative humidity of 74%. The morphology of membranes was investigated by scanning electron microscopy and microflow permporometer. By the addition of the phosphoric acid additive in the casting solution, the morphology of the prepared membranes were changed from a dense sponge structure to a loose asymmetric sponge structure. Due to the addition of catalytic amount of phosphoric acid to NMP casting solution, the mean pore size increased almost $0.2{\mu}m$ and the water flux increased about 3,000 LMH. The temperature of casting plate and exposure time had a apparent effect on the skin layer structure and the pore size and the porosity of the membrane.

• Korean Membrane Journal
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• v.10 no.1
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• pp.1-7
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• 2008

Polystyrene-co-divinylbenzene (PS-co-DVB) asymmetric membranes were prepared. In order to control their structure and mechanical properties the degree of cross-linking and the composition of casting solution were varied. The rubber added PS-DVB membranes was also prepared to overcome the mechanical limitation of cross-linked membrane, and their mechanical properties were investigated. It was revealed that the concentration of polymer in the casting solution affected the determination of skin formation. When the PS-co-DVB membrane consists of styrene-butadiene (SB) rubber or liquid polybutadiene (PBD), the structures formed showed that the PS content in the PS/DVB system played an important role in determining the porous sublayer structure.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.49 no.1
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• pp.9-14
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• 2000

When current flows through a thick conductor such, most of the current flows along outside of the conductor, which is called skin effect. This paper represents a method calculating such a current distribution in the conductor region. The conductor region is divided into some pieces and each piece has its own unknown variable, i.e. current density. The governing equation which expresses Maxwell's equation is combined with the circuit equation with voltage source. The combined equation is solved to obtain current distribution in the conductor. This algorithm is applied to EMC(Electromagnetic Casting) to calculate current density with voltage source.

• Journal of Pharmaceutical Investigation
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• v.29 no.4
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• pp.343-348
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• 1999

The purpose of this study is to prepare the controlled release adhesive patch containing naproxen. Pressuresensitive adhesive (PSA)-type patch was fabricated by casting of polyisobutylene (PIE.) and mineral oil in toluene. Membrane-controlled release (MCR)-type patch was prepared by the attachment of the controlled release membrane on the PSAtype patch. The membrane was mainly composed of Eudragit, polyethylene glycol(PEG) and glycerin. The drug release profile and skin permeation test with various patches were evaluated in vitro. The release of naproxen from PIE-based PSAtype patch with various loading doses fitted Higuchi's diffusion equation. However, the permeation of naproxen through hairless mouse skin from PSA-type patch followed zero-order kinetics. In MCR-type patch, thickness of controlled release membrane affected on the drug release rate highly. In the composition of membrane, the release rate was decreased as the ratio of Eudragit increased. The drug release from the MCR-type patch followed zero order kinetics. The permeation of naproxen through hairless mouse skin from MCR-type patch showed lag time for the intial release period and didn't fit the zero-order kinetics

• Membrane Journal
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• v.18 no.4
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• pp.317-324
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• 2008

Polysulfone membranes were prepared via the phase inversion process. With propionic acid as a nonsolvent additive, polysulfone casting solutions were solidified in an isopropanol bath. Propionic acid (PA) worked as a thermodynamic enhancer for phase separation and as a rheological suppressor for kinetic hindrance. Morphology of the prepared membranes significantly varied with propionic acid content in the casting solution. The dense skin layer, which was identified in the membrane prepared without PA, almost disappeared in the membrane prepared trom PA 10wt%. With 30wt% PA, the membrane revealed the morphological gradient from a nodular skin structure to a sponge-like substructure, including the finger-like cavity. Water permeability increased with PA content, and polyethylene glycol rejection decreased with the nonsolvent content.

• Sim-seong Yeon-gu
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• v.29 no.2
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• pp.127-156
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• 2014

This thesis is an psychological study investigating the meanings of skin from the perspective of analytical psychology. Skin, as the outermost layer of our body, protects the body and carries out essential physiologic functions. It is an organ of the body and also psychological contents can be expressed on it in various forms. We can find sociocultural connotations of skin, some of which are demonstrated in our language. Skin may become a carrier of persona which defines a person's role in the society. And it can be a place where ego is expressed. Eros is the principle of relationship by Jung's definition and skin is the space where eros is realized intensely. Skin may carry meanings as a symbol of transformation. Skin disease can be interpreted as a message from Self in certain cases. The theme of casting off skin in myths and dreams can be an analogy of an individual's sacrifice for individuation, and putting on a skin may imply taking special properties in psychological level.