• Preventive Nutrition and Food Science
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• v.3 no.2
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• pp.203-209
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• 1998

The development of methods for the identification of irradiated foods helps enforce national and international regulations on labelling to ensure the consumer's free choice to buy irradiated or unirradiated foods. and the availabilityof such methods may assist the promotion of international trade in irradiated food products and help prevent abuse of the technology. A number of approaches to determine the physical , chemical, microbiological and biological changes that occur in foods treated with ionizing radiation have been studied. However no single method is universally applicable. Among physical measurements, the leading methods of indentification are electron spin resonance (ESR) spectroscopy and thermoluminescence(TL). ESR is an established non-destructive method for the analysis of free radicals from their traps and TL is the emission of light from irradiated mineral extracts by heating. Viscosity of carbohydrate polymers by causing chain breaks by irradiation, measuring the impedance of potatoes and detection of gases produced radiolytically are promising techniques for identification purposes. Irradiated water-containing foods show significant supercooling when monitored with a differential scanning calorimeter (DSC), which can be applied to identifying irradiated ones.

• Bulletin of the Korean Chemical Society
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• v.14 no.2
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• pp.191-195
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• 1993

Molecular orbital calculations at the extended Huckel level have been carried out for an electron deficient cluster, $Tl_3(FeL_3)_2{(FeL_4)_3}^{-3}$, where L=CO or $H^-$. The LUMO, $2a_2$", is destabilized by the secondary interaction of the LUMO with $1a_2$" on $(FeL_3)_2$ fragment. This is one of six skeletal bonding orbitals which are associated with $Tl-FeL_3$ bonds. Overlap population analysis has been applied to account for two kinds of Tl-Fe bonds. Replacement of the terminal $C_{3v}$, $FeL_4$, by the $C_{2v}$, $FeL_4$ units in cluster results in slight energy stabilization of the cluster.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.527-529
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• 2003

A fructosyltransferase from Leuconostoc mesenteroides TL1 was purified. The molecular mass of the enzyme was estimated to be 38 kDa based on the activity staining. The pH and temperature optima of the enzyme were 6.3 and $40^{\circ}C$, respectivly. Structural analysis of the polymer prepared from sucrose by the enzyme was determined by NMR Spectroscopy: It shows the heterogeneous linkages of levan-like fructan and dextran-like glucan.

• The Korean Journal of Nuclear Medicine
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• v.37 no.5
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• pp.278-287
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• 2003

Purpose: The performance of nitroglycerin-challenged Tc-99m-MIBI quantitative gated SPECT for the detection of viable myocardium was compared with rest/24-hour redistribution Tl-201 SPECT Materials and Methods: In 22 patients with coronary artery disease, rest Tl-20l/ dipyridamole stress Tc-99m-MIBI gated/24-hour redistribution Tl-201 SPECT were peformed, and gated SPECT was repeated on-site after sublingual administration of nitroglycerin (0.6 mg). Follow-up gated SPECT was done 3 months after coronary artery bypass graft surgery. For 20 segments per patient, perfusion at rest and 24-hour redistribution, and wall motion and thickening at baseline and nitroglycerin-challenged state were quantified. Quantitative viability markers were evaluated and compared;(1) rest thallium uptake, (2) thallium uptake on 24-hour redistribution SPECT, (3) systolic wall thickening at baseline, and (4) systolic wall thickening with nitroglycerin-challenge. Results: Among 100 revascularized dysfunctional segments, wall motion improved in 66 segments (66%) on follow-up gated myocardial SPECT after bypass surgery. On receiver operating characteristic (ROC) curve analysis, the sensitivity and specificity of rest and 24-hour delayed redistribution Tl-201 SPECT were 79%, 44% and 82%, 44%, respectively, at the optimal cutoff value of 50% of Tl-201 uptake. The sensitivity and specificity of systolic wall thickening at baseline and nitroglycerin-challenge were 49%, 50% and 64%, 65% at the optimal cutoff value of 15% of systolic wall thickening. Area under the ROC curve of nitroglycerin-challenged systolic wall thickening was significantly larger than that of baseline systolic wall thickening (p=0.004). Conclusion: Nitroglycerin-challenged quantitative gated Tc-99m-MIBI SPECT was a useful method for predicting functional recovery of dysfunctional myocardium.

• Food Science and Preservation
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• v.18 no.3
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• pp.294-301
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• 2011

The aim of this study was to investigate the changes in identification markers of irradiated foods after treatment of the full-overlapped gravitational field energy (FGFE). Wheat and soybean samples were irradiated at 0-5 kGy of Co-60 gamma energy, and analyzed for photostimulated and thermo luminescence characteristics (PSL and TL) and sprouting rate at 0 and 6th month after FGFE treatment. As a screening method for irradiated samples, PSL photon counts (PCs) for the non-irradiated samples appeared negative (<700 PCs), while irradiated samples gave positive (>5,000 PCs). But FGFE-treated irradiated samples appeared intermediate (700-5,000 PCs), showing decreased PCs during storage. The TL analysis on irradiated samples exhibited glow curve peaks in range of $150-200^{\circ}C$ and TL ratio ($TL_1/TL_2$) was also >0.1. Therefore, identification of irradiated samples was possible using thermoluminescence. But the glow curve range of FGFE-treated irradiated samples shifted from $150-200^{\circ}C$ to $180-230^{\circ}C$ and TL intensity was decreased 37-60% resulting from FGFE treatment. After 6 months of storage, all the samples showed a decrease in TL intensity, but identification was still possible. The sprouting rate of irradiated samples decreased by about 72%, whereas that of FGFE-treated irradiated samples showed by about 85%, as compared to non-irradiated samples. More detailed study is required to investigate sprouting phenomena for FGFE-treated samples.

• Journal of Surface Science and Engineering
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• v.33 no.2
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• pp.126-134
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• 2000

This study investigated the bath compositions and plating conditions and crystal structure used for achieving nickel-thallium-phosphorus deposits by means electroless plating. The electroless nickel-thallium-phosphorus deposits were achieved with a bath using sodium hypophosphite as the reducing agent and sodium citrate as the complexing agent. The depositing rate was 10.5mg.$cm^{2-1}$ .$hr^{-1 }$ from the optimistic bath composition, 0.1M nickel sulfate, 0.005M thallium sulfate, 0.2M sodium hypophosphite, and 0.05M sodium citrat and the recommended plating conditions, pH 5.5 and $90^{\circ}C$. The composition of alloy deposits determined by X-ray analysis (EDS) that the Thallium was increased with major increasing concentration of complexing agent and thallium ion in bath solution, it decreased according to the increasing concentrations of reduction agent in the bath solution, Bit Phosphorus showed a contrary to the thallium. It was observed from X-ray diffraction analysis, Scanning Electron Microscopy and Transmission Electron Microscopy. The crystalline structure of deposits was amorphous at the first deposited state but it was changed $Ni-T1-Ni_{5}$ $P_2$ polycrystalline when subjected to 1 hour heat treatment of more than $350^{\circ}C$. TEM observation demonstrated that the microstructure was identical to the result of the XRD at as deposited but it became $Ni-Tl-Ni_{5}$ $P_2$ polycrystalline when heated. And grain size was 10-50nm.

• Journal of Electrical Engineering and Technology
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• v.8 no.2
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• pp.364-370
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• 2013

In the current paper, we propose a new modeling algorithm to analyze the coupling between an incident electromagnetic field (EMF) and a twisted conducting line, which is a kind of non-uniform line. Typically, analysis of external field coupling to a uniform transmission line (TL) is implemented by the Baum-Liu-Tesche (BLT) equation so that the induced load responses can be obtained. However, it is difficult to apply this method to the analysis of a twisted conducting line. To overcome this limitation, we used a chain matrix composed of ABCD parameters. The proposed algorithm expands the dimension of the previous chain matrix to consider the EMF coupling effectiveness of each twisted pair, which is then applied to multi-conductor transmission line (MTL) theory. In addition, we included a comparative study that involves the results of each method applied in the conventional BLT equation and new proposed algorithm in the uniform two-wire TL case to verify the proposed method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.11
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• pp.1569-1574
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• 2011

In this study, the identification of the irradiated seafood cooking drips from Hizikia fusiformis, Enteroctopus dofleini and Thunnus thynnus was conducted. The physical detection methods used included photo-stimulated luminescence (PSL) and thermoluminescence (TL), and the chemical detection methods were hydrocarbons analysis. In the PSL study, all seafood cooking drip samples showed 260~510 photon counts; thus, the PSL method could not be used for the detection of irradiated seafood cooking drips. The TL method could be used for the detection of irradiated H. fusiformis and E. dofleini cooking drips. In both cooking drips, the shapes of the glow curves indicated a specific peak at 150$^{\circ}C$~250$^{\circ}C$, which made it possible to identify the irradiated samples. The hydrocarbons derived by gamma irradiation of T. thynnus cooking drip were not detected due to low concentration and inconsistent content of fatty acids in the untreated T. thynnus cooking drip.

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.227-232
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• 2012

Galectins are generally believed to be potential candidates for use in the development of novel antiinflammatory agents or as selective modulators of the immune response. In particular, galectin-9 exhibits some of the extracellular functions, including cell aggregation, adhesion, chemoattraction, activation, and apoptosis. Tl-galectin (Tl-gal, galectin-9 homologue gene) was isolated from an adult worm of the Toxascaris leonina. The full-length Tl-gal gene, which was incorporated into pET-28a, was overexpressed in E. coli and purified by nickel affinity and gel filtration chromatographies. The purified Tl-gal was crystallized using the hangingdrop vapor-diffusion method. The crystal belonged to the tetragonal space group $P4_1$, with unit-cell parameters of a = b = $75.7\AA$ and c = $248.4\AA$. The crystals were obtained at $20^{\circ}C$ and diffracted to a resolution of $3.0\AA$. The asymmetric unit contained four molecules of Tl-gal, which gave a crystal volume per protein mass (Vm) of $2.8\AA^3Da^{-1}$ and a solvent content of 54.1%.

• Animal cells and systems
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• v.12 no.4
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• pp.305-311
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• 2008

Age and growth of the mudskipper, Scartelaos gigas were investigated using the second actinost bone of the pectoral girdle, based on an analysis of 560 individuals collected from the mud flats in south west Korea. Specimens were collected semimonthly from March to September of 2003. Actinost and ring radii of each ring group showed a direct one-to-one relationship, with ring radius increasing in tandem with actinost radius. Monthly change in the marginal indices showed that ring formation occurred between May and July(mainly June), being supported by the monthly change in the gonadosomatic(highest in June) and hepatosomatic(lowest in July) indices. Because the species has not been found since November, when air temperature was less than about $10^{\circ}C$, it is thought to enter to hibernation. Therefore, it was suggested that the two new actinost rings may appear a year: one during the spawning season(May-July) and another during hibernation(since November). Although the growth of S. gigas must be limited to short periods each year from March to April and from August to October, its growth rate was considerably fast. The von Bertalanffy growth parameters of S. gigas were $TL_{\infty}$=179.36 mm, K=0.78 $year^{-1}$, $t_0$=-0.7762, and age-length key were $TL_1$=134.3 mm, $TL_2$=158.6 mm, $TL_3$=169.1 mm, $TL_4$=175.0 mm.