• The Journal of Korean Physical Therapy
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• 제14권4호
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• pp.163-171
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• 2002

Neuromuscular junction consist of presynaptic membrane, synaptic cleft and postsynaptic membrane. In the neuromuscular junction, presynaptic membrane is the motor nerve terminal, have many synaptic vesicle. Postsynaptic membrane is the motor end plate of muscle fiber and the most striking structural features are the deep infolding of the sarcolemma. Between the nerve and muscle cells, there is a synaptic cleft of some 50-100nm. This review shows the ultrastructure and function of neuromuscular junction, summarizes the current knowledge.

• 한국축산식품학회지
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• 제31권1호
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• pp.1-8
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• 2011

A unique biophysical membrane which surrounds the milk fat globules is called the milk fat globule membrane (MFGM). Various researches were studied about origin, composition, structure and bioactive components of MFGM. Bioactive protein components of MFGM play an important beneficiary function such as defense mechanism in new born. Among the bioactive lipid components from MFGM phospholipids showed health enhancing functions. The phospholipids also help in the production of certain dairy product from deterioration. MFGM phospholipids also showed antioxidant activity in some dairy products such as butter and ghee produced from milk of buffalo. Based on the beneficial effects, researchers developed MFGM as functional ingredients in various food products. This current review focuses on health enhancing function of MFGM and its components in various dairy products.

• Journal of Advanced Marine Engineering and Technology
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• 제28권6호
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• pp.993-999
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• 2004

The estimation of fatigue life at the design stage of membrane type LNG tank is very important in order to arrive at feasible and cost effective solutions considering the total lifetime of the tank. In this study, the practical procedure of fatigue life prediction by use of cumulative damage factors based on Miner-Palmgren hypothesis and probability density function has been shown with the corner region of Gaz Transport Membrane type LNG tank being used as an example. In particular the parameters of Weibull distribution that determine the stress spectrum are discussed. The main results obtained from this study are as follows: 1. The recommended value for the shape parameter of Weibull distribution for the LNG tank is 1.1 in case of using the direct calculation method proposed in this study. 2. The calculated fatigue life is influenced by the shape parameter of Weibull distribution and stress block. The safe fatigue design can be achieved by using higher value of shape parameter and the stress blocks divided into more stress blocks.

• International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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• 제6권1호
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• pp.7-14
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• 2003

The interaction of monochromatic incident waves with a submerged horizontal porous membrane is investigated in the context of two-dimensional linear hydro-elastic theory. It is assumed that the membrane is made of material with very fine pores so that the normal velocity of the fluid passing through the porous membrane is linearly proportional to the pressure difference between two sides of the membrane (e.g. Darcy's law). Using the Eigen-function expansion method, the wave-blocking performance of a submerged horizontal porous membrane is tested with various membrane tensions, porosities, lengths, and submerged depths. It is found that an optimal combination of design parameters exists for given water depth and wave characteristics.

• Korean Membrane Journal
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• 제4권1호
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• pp.12-19
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• 2002

Nanofiltration of aqueous dye solutions was carried out using polyamide (PA) nanofiltration (NF) composite membranes. The PA composite membranes were prepared by the interfacial polymerization of piperazine (PIP) and trimesoyl chloride (TMC) on the surface of microporous polysulfone (PSf) ultrafi1tration (UF) membranes. After characterization in terms of their permeation performance and surface ionic property, they were used for the separation of dye solutions such as Direct Red 75, 80, 81, and Direct Yellow 8 and 27. The separation conditions were varied to study the factors affecting on the permeation performance of the membranes: different concentrations of dye solutions, operating temperature and time, and flow rate of a feed solution. The surface property of the membrane, especially its ionic property, as a function of operating time was examined with a zeta-potentiometer and the relationship between the surface chemistry of the membrane and its permeation properties was also studied.

• Membrane and Water Treatment
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• 제11권2호
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• pp.97-109
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• 2020

Membrane fouling is the main drawback of membrane technology. Frequent membrane cleaning and membrane replacement are, therefore, required to reduce membrane fouling that causes permeate flux reduction, lower rejection, or higher operating pressure. Studies have proved that the alteration of membrane properties is the key controlling factor in lessening membrane fouling. Among stimuli-responsive membranes, thermo-responsive membrane is the most popular, with a drastic phase transition and swelling-shrinking behavior caused by the temperature change. In this study, the thermo-responsive ability of two commercial membranes, PolyCera® Titan membrane and PolyCera® Hydro membrane, at different temperatures was studied on the antifouling function of the membrane in palm oil mill effluent (POME) treatment. The evaluation of the membrane's thermo-responsive ability was done through three cycles of adsorption (fouling) and desorption (defouling) processes in a membrane filtration process. The experimental result depicted that PolyCera® Hydro membrane had a higher membrane permeability of 67.869 L/㎡.h.bar than PolyCera® Titan membrane at 46.011 L/㎡.h.bar. However, the high membrane permeability of PolyCera® Hydro membrane was compensated with low removal efficiency. PolyCera® Titan membrane with a smaller mean pore size had better rejection performance than PolyCera® Hydro membrane for all tested parameters. On the other hand, PolyCera® Titan membrane had a better hydrodynamic cleaning efficiency than PolyCera® Hydro membrane regardless of the hydrodynamic cleaning temperature. The best hydrodynamic cleaning performed by PolyCera® Titan membrane was at 35℃ with the flux recovery ratio (FRR) of 99.17 ± 1.43%. The excellent thermo-responsive properties of the PolyCera® Titan membrane could eventually reduce the frequency of membrane replacement and lessen the use of chemicals for membrane cleaning. This outstanding exploration helps to provide a solution to the chemical industry and membrane technology bottleneck, which is the membrane fouling, thus reducing the operating cost incurred by the membrane fouling.

• 대한한방내과학회지
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• 제18권1호
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• pp.147-155
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• 1997

This study was undertaken to determine whether Salviae-radix (SVR) exraction exerts benefical effect against oxidant-induced inhibition of tetraethylammonium (TEA) uptake which is actively secreted by renal proximal tubules. TEA uptake increased as function of incubation time to 60 min. When renal cortical slices were exposed to 50 mM $H_2O_2$, TEA uptake was significantly inhibited. The inhibition was significantly protected by addition of 0.5% SVR extraction. The benefical effect of SVR was dose-dependent over the concentration range of 0.1-1%; $H_2O_2$ (50 mM)-induced inhibition of TEA uptake was completely protected by 0.5-1% SVR extraction. $H_2O_2$ increased LDH release which was accompanied by an increase in lipid peroxidation in renal cortical slices. These changes were prevented by 0.5% SVR. These results suggest that SVR exerts benefical effect against oxidant-induced impairment of membrane transport function, this effect may be due to by an antioxidant action.

• Journal of Microbiology and Biotechnology
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• 제30권12호
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• pp.1835-1842
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• 2020

Ergosterol, an essential constituent of membrane lipids of yeast, is distributed in both the cell membrane and intracellular endomembrane components such as vacuoles. Honokiol, a major polyphenol isolated from Magnolia officinalis, has been shown to inhibit the growth of Candida albicans. Here, we assessed the effect of honokiol on ergosterol biosynthesis and vacuole function in C. albicans. Honokiol could decrease the ergosterol content and upregulate the expression of genes related with the ergosterol biosynthesis pathway. The exogenous supply of ergosterol attenuated the toxicity of honokiol against C. albicans. Honokiol treatment could induce cytosolic acidification by blocking the activity of the plasma membrane Pma1p H+-ATPase. Furthermore, honokiol caused abnormalities in vacuole morphology and function. Concomitant ergosterol feeding to some extent restored the vacuolar morphology and the function of acidification in cells treated by honokiol. Honokiol also disrupted the intracellular calcium homeostasis. Amiodarone attenuated the antifungal effects of honokiol against C. albicans, probably due to the activation of the calcineurin signaling pathway which is involved in honokiol tolerance. In conclusion, this study demonstrated that honokiol could inhibit ergosterol biosynthesis and decrease Pma 1p H+-ATPase activity, which resulted in the abnormal pH in vacuole and cytosol.

• 대한약침학회지
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• 제4권2호
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• pp.49-56
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• 2001

This study was undertaken to determine whether Scutellaria baicalensis Georgi (SbG) extract exerts the protective effect against $HgCl_2$-induced alterations in membrane transport function in rabbit renal cortical slices. The slices were treated with 0.1 mM $HgCl_2$ for 60 min at $37^{\circ}C$. $HgCl_2$ caused an inhibition in PAH uptake by renal cortical slices. Such an effect was accompanied by depressed $Na^+-K^+$-ATPase activity and ATP depletion. SbG prevented $HgCl_2$-induced inhibition of PAH uptake in a dose-dependent manner at the concentration ranges of 0.01-0.1%. $HgCl_2$-induced inhibition of $Na^+-K^+$-ATPase activity and ATP depletion were significantly prevented by 0.05% SbG. These results suggest that SbG prevents $HgCl_2$-induced alterations in membrane transport function in rabbit renal cortical slices. Such protective effects of SbG may be attributed to inhibition of peroxidation of membrane lipid.

• 자연, 터널 그리고 지하공간
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• 제21권2호
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• pp.103-116
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• 2019

Permanent sprayed concrete tunnel linings waterproofed with bonded membranes have been used at a number of important traffic projects over the last decade. Research has been carried out in several teams in order to increase the understanding of the function, properties and behavior of such linings under different loading and boundary conditions. The basic layout of this lining gives fundamental different system properties compared to the traditional lining systems. The main differences pertain to the groundwater exposure and the resulting hydraulic loading, the response of the concrete and membrane materials to this loading, as well as the geomechanically induced loading of the lining structure. The current understanding of the function and properties of such lining structures is presented in the paper based on review of recent research carried out in Norway, as well as field observations and monitoring carried over a several years. The influence of the water exposure on the final condition of the concrete and membrane materials has proven to be of vital importance for proper material testing and acceptance, assessments of the mechanical contribution of the bonded membrane, as well as assessments of the longterm durability of such linings. Obtaining realistic material parameters for the concrete and membrane materials subject to the boundary conditions posed by the groundwater exposure in an undrained structure is emphasized. Finally, some recent results from currently ongoing research on such linings, particularly the hydraulic response of the rock mass and the long term behavior of the concrete and membrane materials are presented.