• Journal of Plant Biotechnology
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• v.5 no.4
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• pp.239-244
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• 2003

A protocol has been developed for rapid large scale clonal propagation of an aromatic endangered medicinal plant, Hemidesmus indicus R. Br. with the elimination of the problems such as premature leaf fall and callus formation during caulogenesis and rhizogenesis. Multiple shoots were induced from shoot tip and nodal explants on Murashige and Skoog (MS) medium supplemented with 1 mg/L Benzylaminopurine (BAP) and 0.5 mg/L Napthaleneaceticacid (NAA). Addition of 15 mg/L adenine sulphate to the above medium checked leaf abscission completely, reduced the time required for caulogenesis and restored morphogenetic potential after several subcultures. The in vitro grown propagules were rooted in 1/2 MS medium supplemented with 2 mg/L Indolebutyric acid (IBA) +1 mg/L NAA and sucrose 0.7% (w/v). Addition of charcoal at 100 mg/L to the rooting medium quickened root initiation with a complete check on callus formation. The effect of sucrose concentration on both caulogenesis and rhizogenesis was also studied. The resultant plantlets were acclimatized and grown in fields where ninety eight percent of the rooted shoots survived and grew normally. The estimation of the secondary metabolite content in the shoots of the regenerated plant and the mother plant indicated that the concentration of the three secondary metabolites lupeol, vanillin and rutin was similar.

• Journal of the Institute of Convergence Signal Processing
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• v.14 no.1
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• pp.1-5
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• 2013

The two major problems related to the blood flow in replaced prosthetic heart valve are thrombus formation and hemolysis. Reliability of prosthetic valve is very important because its failure means the death of patient. There are many factors affecting the valvular failures and their representatives are mechanical failure and thrombosis, so early noninvasive detection is essentially required. The purpose of this study is to detect the various thromboses formation by using acoustic signal acquisition and its spectral analysis on the frequency domain. We made the thrombosis models using Polydimethylsiloxane (PDMS) and they are thrombosis model on the disc, around the sewing ring and fibrous tissue growth across the orifice of valve. Using microphone and amplifier, we measured the acoustic signal from the prosthetic valve, which is attached to the pulsatile mock circulation system. A/D converter sampled the acoustic signal and the spectral analysis is the main algorithm for obtaining spectrum. Then the spectrum of normal and 5 different kinds of abnormal valve were obtained. Each spectrum waveform shows a primary and secondary peak. The secondary peak changes according to the thrombus model. To quantitatively distinguish the frequency peak of the normal valve from that of the thrombosed valves, analysis using a neural network was employed. Acoustic measurement has been used as a noninvasive diagnostic tool and is thought to be a good method for detecting possible mechanical failure or thrombus.

• Journal of Microbiology and Biotechnology
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• v.26 no.11
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• pp.2006-2011
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• 2016

The marine sponges Hyrtios and Haliclona species, both of which are known to produce secondary bioactive metabolites, were used to extract 1304KO-327 and 1304KO-328. Such secondary metabolites are potentially antibacterial, antiviral, anti-inflammatory, antitumoral, antifungal, and antiplasmodial. In the present study, the effects of 1304KO-327 and 1304KO-328 were studied for their clinical and pathological importance. The cytotoxicity of 1304KO-327 and 1304KO-328 was assessed via MTT(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay on HT-29, Caco-2, and Raw 264.7 cells. Rotavirus-infected Caco-2 cells were used to prove the antiviral effects of the marine sponge extracts. The test results cogently proved that the virus-inhibiting effects of the sponge extracts improved with extract concentration. Anti-inflammatory effects of the marine sponge extracts were tested on Lipopolysaccharide-treated Raw 264.7 cells. Nitric oxide and cytokine were produced by treatment of the cells with LPS and the inhibiting effects of the sponge extracts on $IL-1{\beta}$ formation were investigated. This study found that the NO production was decreased dose dependently, and $IL-1{\beta}$ formation was significantly reduced by the marine sponge extracts.

• Journal of Environmental Science International
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• v.1 no.1
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• pp.19-33
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• 1992

The high oxidants, which occur the daily maximum concentrations in the afternoon, are transported into the other region via long range transport mechanisms or trapped within the shallow mixing boundary layer and then removed physically (deposition, transport by mountain wind, etc.) and chemically (reaction with local sources). Therefore, modeling formation of photochemical oxidants requires a complex description of both chemical and meteorolog ital processecs . In this study, as a part of air quality studies, we reviewed various aspects of photochemical modeling on the basis of currently available literature. The result of the review shows that the model is based on a set of coupled continuity equations describing advection, diffusion, transport, deposition, chemistry, emission. Also photochemical oxidant models require a large amount of input data concerned with all aspects of the ozone life cycle. First, emission inventories of hydrocarbon and nitrogen oxides, with appropriate spatial and temporal resolution. Second, chemical and photochemical data allowing the quantitative description of the formation of ozone and other photochemically-generated secondary pollutants. Third, dry deposition mechanisms particularly for ozone, PAN and hydrogen peroxide to account for their removal by absorption on the ground, crops, natural vegetation, man-made and water surfaces. Finally, meteorological data describing the transport of primary pollutants away from their sources and of secondary pollutants towards the sensitive receptors where environmental damage may occur. In order to improve our present study, shortcomings and limitation of existing models are pointed out and verification Process through observation is emphasized.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.5
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• pp.358-364
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• 1998

Retrograde well is a new process for ULSI fabrication. High energy ion implantation has been used for retrograde well formation. In this paper the forming condition for retrograde well using high energy ion implantation is compared with that for conventional well. TW signals for retrograde p-,n-well($900^{\circ}C$),after annealing are similar trends to those of conventional ones($1150^{\circ}C$), however the signals for RTA have the highest value because of small thermal budget. Junction depths of retrograde well are varied from about 1.2 to $3.0\{mu}m$ as for conventional well. The peak concentrations of retrograde well, however, are about 10 times higher in values than those of conventional ones so that they can be used as any types of potential barriers or gettering sites. The critical dose for phosphorus implantation in our experiments is between $3\times10^{13} and 1\times10^{14}/cm^2$. Under the above critical dose, there are many secondary defects near projected range such as dislocation lines and dislocation loops.

• Korean Journal of Materials Research
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• v.12 no.7
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• pp.580-586
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• 2002

The effect of processing and designing variables such as pouring temperature(1400 or $1500^{\circ}C$), inoculation and risering design(T and H type) on the formation of defects such as external depression, primary and secondary shrinkage cavities in GC150 gray cast iron was investigated. In T type risering design, external depression or primary shrinkage cavity due to liquid contraction was formed in all of the eight cases. Regardless of its modulus value, the riser could not function properly in T type risering design because directional solidification was not promoted toward the riser. On the other hand, the four cases of H type risering design in which thermal sleeves were set onto the risers produced defect-free castings. In both types of the risering designs, secondary shrinkage cavity caused by solidification contraction was not observed in the casting because of the expansion pressure due to graphite precipitation and the application of rigid pep-set mold. The degree of external depression or primary shrinkage cavity was reduced with lowered pouring temperature. The effect of inoculation was diminished because of the high carbon equivalent of GC 150 gray cast iron.

• Journal of the Korean Society for Railway
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• v.6 no.2
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• pp.122-128
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• 2003

The acceptance test of KTX has been performed in Korea. During the test, lateral vibration of carbody over the accepted value called sway was found. Many activities have been taken to find the cause of the vibration and the counter-measure. KTX has 20 car trainset formation whose trailer cars are linked by articulate bogies. So this study is performed to see the effects of long trainset formation on vehicle dynamics and the train stability by 16 car vehicle model. Firstly the reliable vehicle model which shows well the tendencies appeared in the tests on the high speed test line is required to find the cause of lateral vibration and the countermeasure. Vehicle model was made for the analysis with VAMPIRE. The analysis results show that secondary air spring lateral stiffness is the most significant parameter to cause carbody lateral vibration. Mode analysis results show that the least damped mode shape is similar to the vibration pattern shown in the tests that the amplitude of the motion increases along the train set and decreases in the tail part. The lateral vibration was "appeared at the speed range between 100km/h and 200km/h and disappeared at the low speed and the high speed.

• Bulletin of the Korean Chemical Society
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• v.30 no.8
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• pp.1845-1850
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• 2009

We have performed replica-exchange molecular dynamics (REMD) simulations on the dimer formation of fibrilforming segments of $\alpha$-Synuclein (residues 71 - 82) using implicit solvation models with two kinds of force fields- AMBER parm99SB and parm96. We observed spontaneous formation of dimers from the extensive simulations, demonstrating the self-aggregating and fibril forming properties of the peptides. Secondary structure profile and clustering analysis showed that dimers with antiparallel $\beta$-sheet conformations, stabilized by well-defined hydrogen boding, are major species corresponding to global free energy minimum. Parallel dimers with partial $\beta$-sheets are found to be off-pathway intermediates. The relative instability of the parallel arrangements is due to the repulsive interactions between bulky and polar side chains as well as weaker backbone hydrogen bonds.

• Horticultural Science & Technology
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• v.28 no.6
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• pp.1039-1050
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• 2010

Carrot is one of the useful crops used abundantly in cooking in Western as well as Asia regions such as China and Korea. However, seed coats have hairs which should be removed to increase germination rate. Furthermore, because of seed hairs, farmers face several additional losses, such as time consumption, manpower, capital and so on, for seed handling. To prevent these problems, study of gene related hair formation using short-hair seed lines is required. We analyzed genes related to hair formation from seed through expressed sequenced tag (EST) profiling, based on the fact that the development of carrot seed hair is related to cellulose synthesis pathway in secondary cell wall synthesis stage. To study the gene expression related to hair formation of the carrot seed, a cDNA library was constructed by using the early maturation stage of the short-hair line (659-1) and hairy seed line (677-14). In short-hair (659-1) and hairy seed (677-14) lines, results from of EST profiling through BLASTX search analysis using the NCBI database showed that 172 and 224 unigenes had significant homology with known protein sequences, whereas 233 and 192 unigenes were not, respectively. All ESTs were grouped into 16 categories according to their putative functions. Twenty nine unigenes among all ESTs were considered to be genes regulating seed hair development from cellulose synthesis pathway during secondary cell wall synthesis stage; in results, 14 unigenes related to seed hair development were found only in hairy seed line.

• Korean Journal of Materials Research
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• v.6 no.7
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• pp.733-741
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• 1996

In this study MeV Si self ion implantations were done to reveal the intrinsic behavior of defect formation by excluding the possibility of chemical interactions between substrate atoms and dopant ones. Self implantations were conducted using Tandem Accelerator with energy ranges from 1 to 3 MeV. Defect formation by high energy ion implantation has a significant characteristics in that the lattice damage is concentrated near Rp and isolated from the surface. In order to investigate the energy dependence on defect formation, implantation energies were varied from 1 to 3 MeV under a constant dose of $1{\times}10^{15}/cm^2$. RBS channe!ed spectra showed that the depth at which as-implanted damaged layer formed increases as energy increases and that near surface region maintains better crystallinity as energy increases. Cross sectional TEM results agree well with RBS ones. In a TEM image as-implanted damaged layer appears as a dark band, where secondary defects are formed upon annealing. In the case of 2 MeV $Si^+$ self implantation a critical dose for the secondary defect formation was found to be between $3{\times}10^{14}/cm^24$ and $5{\times}10^{14}/cm^2$. Upon annealing the upper layer of the dark band was removed while the bottom part of the dark band did not move. The observed defect behavior by TEM was interpreted by Monte Carlo computer simulations using TRIM-code. SIMS analyses indicated that the secondary defect formed after annealing gettered oxygen impurities existed in silicon.