• 한국ITS학회:학술대회논문집
• /
• 2005.11a
• /
• pp.180-182
• /
• 2005

• Journal of the Korean Society of Clothing and Textiles
• /
• v.17 no.2
• /
• pp.329-338
• /
• 1993

The purpose of this study was to design an instrument to simulate the Human-Clothing-Environment system and evaluate the water vapour transport properties of sweat absorbent PET fabrics. The instrument was composed of sweat generating part, clothing part which can simulate clothing layers, and enviromental part. As specimens, sweat absorbent PET, regular PET, cotton, nylon and acrylics fabrics were included. For the water vapour transport(WVT), relative humidities and temperatures were measured by film type humidity sensors and thermocouples, respectively. Water vapour pressures were calculated with measured RH's and temperatures. For the liquid water transport, wickability and demand wettability were measured. Results showed that there was a difference in terms of water vapour transport mechanism depending on the fiber type ; sweat absorbent PET showed higher WVT at the transient period then equilibrated, whereas other fabrics showed lower WVT at the transient period then increased continuously. These differences are expected to affect to the difference in the comfort properties of clothings. Sweat absorbent PET showed higher demand wettability and wickability than other fabrics. Wide application of the instrument was also suggested.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2004.04a
• /
• pp.243-247
• /
• 2004

Tile development of a porous iron-oxide coated sand filter system can be modelled with the analytical solution of tile transport equation in order to obtain the operating parameters and investigate the mechanism of arsenic removal. The adsorbed amount from the model simulation showed the limitation of adsorption removal during arsenic transport. A loss reaction term in the transport equation plays a role in the mass loss in column conditions, and then resulted into the better model fitting, particularly, for arsenate. Further, the competitive oxyanions delayed the breakthrough near MCL (10 $\mu$g/L) due to the competitive adsorption. This is the reason why arsenate can be strongly attracted in tile interface of an iron-oxide coated sand, and competing oxyanions can occupy the adsorption sites. Therefore, arsenic retention was regulated by non-equilibrium of arsenic adsorption in a porous iron-oxide coated sand media. The transport-limited process seemed to be affect the arsenic adsorption by coated sand.

• Journal of Nutrition and Health
• /
• v.30 no.6
• /
• pp.658-668
• /
• 1997

Path of a small hydrophobic molecule through the aqueous cytoplasma is not linear. Partition may favor membrane binding by several orders of magnitude : thus significant membrane association will markedly decrease the cytosolic transport rate. The presence of high concentration of soluble binding proteins for these hydrophobic molecules would compete with membrane association and thereby increase transport rate. For long chain fatty acid molecules, a family of cytosolic binding proteins collectively known as the fatty acid binding proteins(FABP), are thought to act as intracellular transport proteins. This paper examines the mechanism of transfer of fluorescent antyroyloxy-labeled fatty acids(AOFA) from purified FABPs to phosholipid membranes. With the exception of the liver FABP, AOFA is transferred from FABP by collisional interaction of the protein with a acceptor membrane. The rate of transfer increased markedly when membranes contain anionic phospholipids. This suggests that positively charged residues on the surface of the FABP may interact with the membranes. Neutralization of the surface lysine residues of adipocyte FABP decreased fatty acid transfer rate, and transfer was found to proceed via aqueous diffusion rather than collisional interaction. Site specific mutagenesis has further shown that the helix-turn-helix domain of the FABP is critical for interaction with anionic acceptor membranes. Thus cytosolic FABP may function in intracellular transport of fatty acid to decrease their membranes association as well as to target fatty acid to specific subcellular sites of utilization.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 2001.11a
• /
• pp.91-91
• /
• 2001

Nramp2, also known as DMT1 and DCT1, is a 12-transmembrane domain protein responsible for dietary iron uptake as well as metal ions such as lead, manganese, zinc, copper, nickel, cadmium, and cobalt. High expression of DMT1 increase lead uptake, and DMT1-dependent lead transport was H -dependent and inhibited by iron ions. The molecular mechanism of lead transport in CNS is as yet unknown. although interactions between iron and lead at the level of absorption have been known for some time. The process of lead uptake into astrocytes was not known yet. Nramp2 may mediate transport of heavy metal into astrocytes. We investigated whether Nramp2 mediate transport of lead into astrocytes. And we do whether Nramp2 was expressed highly by deprivation of iron in Astrocytes, and lead uptake into astrocytes was influenced by expression of Nramp2. Immortalized human fetal astrocyte(SV-FHA) cells were cultured in medium containing Dulbecco's modified Eagle's medium and treated with Deferoxamine. Northern blot analysis was done for determining mRNA level of DMT1 and lead uptake assay was done in incubation condition of pH 5.5 and 7.4.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.19 no.5
• /
• pp.1330-1336
• /
• 2005

This study was carried out to investigate the motor activity and glucose transport and metabolism of Gaewool-Whadam-Jian(GWJ) in rat gastro-intestinal tract. The motor activity of the rat gastro-intestinal tract has been investigated by means of measuring barium sulfate passage degrees. Atropine treatment significantly delayed barium sulfate transit, and GWJ pretreatment increased intestinal motor activity, but not significant. GWJ administration showed no toxicity to kidney and liver. Transport and metabolism of glucose were studied in everted sac of rat small intestine with incubation under several conditions. The transport and metabolism of glucose were greater at jejunum than ileum. So, everted jejunum of rat were used to study the effect of GWJ. When GWJ were treated, the concentration of glucose were higher than untreated group. This result was thought to be influenced by the glucose in GWJ. When 2, 4 dinitrophenol and phlorizin were treated, the transport and metabolism of glucose were decreased, but GWJ treated together, the concentration of glucose in serosal solution increased. Gastric juice secretion and total acidity significantly decreased by administration of GWJ through duodenum region. The mechanism of effect of GWJ was still unidentified, Dut through continuous investigation, the effect of GWJ should be investigated.

• Journal of Microbiology
• /
• v.41 no.2
• /
• pp.78-82
• /
• 2003

We identified two proteins in Haemophilus influenzae Rd that exhibited high similarity to two major serine transporters of Escherichia coli (SstT and SdaC). Then, we investigated serine transport in H. influenzae Rd and detected $Na^{+}$-stimulated L-serine transport activity. The optimum NaCl concentration for this stimulation was about 20 mM. The uptake of $Na^{+}$ by H. influenzae Rd was found to be elicited by L-serine influx, which supports the idea that L-serine is transported by a mechanism of $Na^{+}$/serine symport. No uptake of $H^{+}$ elicited by L-serine influx was detected. $Na^{+}$/serine symport activity was not inhibited by other amino acids such as L-threonine or D-serine. Two distinct Km values were obtained from the kinetic analysis of serine transport. Thus, two serine transport pathways may exist in H. influenzae Rd, and it appears that both systems are stimulated by $Na^{+}$.

• Journal of environmental and Sanitary engineering
• /
• v.10 no.3
• /
• pp.45-55
• /
• 1995

This study was carried out to elucidate the toxic mechanism of cadmium in peripheral nerve. An animal model of cadmium neuropathy was induced by feeding diet containing cadmium to Sprague- Dawley rat (or two weeks. Four weeks aged Sprague- Dawley rats were divided into four groups : normal control group, 10ppm- cadmium treated group, 100ppm- cadmium treated group, 1000ppm- cadmium treated group, reference drug- treated group. All rats were sacrificed at the end of two weeks for assessing the development of cadmium neuropathy, These results obtained were summarized as follows : 1. Cadmium reduced peripheral flow of both acetylcholinesterase and cholinesterase in rat sciatic nerve. 2. The toxic mechanism of cadmium might be the result of an reduction of myo-inositol concentration in peripheral nervous system 3. Reduction in myo-inositol content of peripheral nerve resulted from the inhibition of sodium- Potassium ATPase activity, which is responsible for myo-inositol transport, by cadmium 4. Oral administration of myo-inositol improved the flow of both acetylcholinesterase and cholinesterasenerve in cadmium intoxicated rat. These results suggest that mild cadmium neuropathy might be diagnosed by checking nervous myo-inositol content and oral administraion of myo-inositol might prevent the development of severe cadmium neuropathy with special reference to detective axonal transport.

• Korean Journal of Materials Research
• /
• v.26 no.1
• /
• pp.35-41
• /
• 2016

The electrical transport properties of $La_{0.5}Sr_{0.5}CrO_3$ below room temperatures were investigated by dielectric, dc resistivity, magnetic properties and thermoelectric power. Below $T_c$, $La_{0.5}Sr_{0.5}CrO_3$ contains a dielectric relaxation process in the tangent loss and electric modulus. The $La_{0.5}Sr_{0.5}CrO_3$ involves the transition from high temperature thermal activated conduction process to low temperature one. The transition temperature corresponds well to the Curie point. The relaxation mechanism has been discussed in the frame of electric modulus spectra. The scaling behavior of the modulus suggests that the relaxation mechanism describes the same mechanism at various temperatures. The low temperature conduction and relaxation takes place in the ferromagnetic phase. The ferromagnetic state in $La_{0.5}Sr_{0.5}CrO_3$ indicates that the electron - magnon interaction occurs, and drives the carriers towards localization in tandem with the electron - lattice interaction even at temperature above the Curie temperature.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.7 no.3
• /
• pp.471-489
• /
• 2013

Data compression at the transport layer could both reduce transmitted bytes over network links and increase the transmitted application data (TCP PDU) in one RTT at the same network conditions. Therefore, it is able to improve transmission efficiency on Internet, especially on the networks with limited bandwidth or long delay links. In this paper, we propose an on-the-fly TCP data compression scheme, i.e., the TCPComp, to enhance TCP performance. This scheme is primarily composed of the compression decision mechanism and the compression ratio estimation algorithm. When the application data arrives at the transport layer, the compression decision mechanism is applied to determine which data block could be compressed. The compression ratio estimation algorithm is employed to predict compression ratios of upcoming application data for determining the proper size of the next data block so as to maximize compression efficiency. Furthermore, the assessment criteria for TCP data compression scheme are systematically developed. Experimental results show that the scheme can effectively reduce transmitted TCP segments and bytes, leading to greater transmission efficiency compared with the standard TCP and other TCP compression schemes.