• Food Science of Animal Resources
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• v.28 no.3
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• pp.276-282
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• 2008

It is estimated that over 80% of deer antlers produced in the world are consumed in Korea. However, mislabeling or fraudulent replacement of costly antlers with cheaper ones is one of the most common problems in the domestic antler market. Therefore, there is a great need for the development of technology to identify species of antlers. This study was carried out to develop an accurate and reliable method for the identification and authentication of species or subspecies of antlers using DNA sequence analysis and comparison of mitochondrial cytochrome band D-loop region genes among antlers of five deer species, Cervus elaphus sibericus, Cervus elaphus canadensis, Cervus nippon, Cervus elaphus bactrianus and Rangifer tarandus. A variable region of cytochrome band D-loop genes was amplified using PCR with specifically designed primers and sequenced directly. The cytochrome band D-loop region genes showed different DNA sequences between the species of antlers and thus it is possible to differentiate between species on the basis of sequence variation. To distinguish between reindeer (Rangifer tarandus) antlers and other deer antlers, PCR amplicons of the cytochrome b gene were digested with the restriction enzymes NlaIV and TaqI, respectively, which generates a species-specific DNA profile of the reindeer. In addition, samples of 32 sliced antlers labeled Cervus elaphus sibericus from commercial markets were collected randomly and the mt DNA D-loop region of these antler samples was sequenced. Among the antler samples investigated, only 62.5% were from Cervus elaphus sibericus, and others were from Cervus elaphus bactrianus (25.0%), elk (Cervus elaphus canadensis) and reindeer (Rangifer tarandus). Our results suggest that DNA sequencing of mt DNA and PCR-RFLP methods using NlaIV and TaqI enzymes are useful for the identification and discrimination of deer antler species by routine analysis.

• Journal of radiological science and technology
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• v.31 no.3
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• pp.287-292
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• 2008

Position information of radiation interactions in detection material is essential to reconstruct a radiation source image. With most position sensing techniques, the position information of a single interaction inside the detectors can be precisely obtained. Each interaction position of multi-scattering inside scintillators, however, can not be individually measured and only the average of the scattering positions can be obtained, which causes the uncertainty in the measured interaction position. In this paper, the position uncertainties due to the multi-scattering were calculated by Monte Carlo simulation. The simulation model was a 50 by 50 by 5 mm $LaCl_3$(Ce) scintillator(pixel size is 2 by 2 by 5mm) which was utilized for the dual collimation camera. The dual collimation camera uses the information from both photoelectric effect and Compton scattering, and therefore, position uncertainties for both partial and full energy deposition of radiation interactions are calculated. In the case of partial energy deposition(PED), the standard deviations of positions are less than $1{\sim}2mm$, which means the uncertainty caused by multi-scattering is not significant. Because the effect of the multi-scattering with PED is insignificant, the multi-scattering has little effect on the performance of Compton imaging of dual collimation camera. In the case of full energy deposition(FED), however, the standard deviation of the positions is about twice that of the pixel size of the 1stdetector, except for 122keV incident radiations. Therefore, the standard deviations caused by multi-scatterings should be considered in the design of the coded mask of the dual collimation camera to avoid artifact on the reconstructed image. The position uncertainties of the FEDs are much larger than those of the PEDs for all radiation energies and the ratio of PEDs to FEDs increases when the incident radiation energy increases. The position uncertainties of both PEDs and FEDs are dependent on the incident radiation energy.

• Geophysics and Geophysical Exploration
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• v.8 no.1
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• pp.50-58
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• 2005

Recently, the imaging of geological structures beneath water-covered areas has been in great demand because of numerous tunnel and bridge construction projects on river or lake sites. An electrical resistivity survey can be effective in such a situation because it provides a subsurface image of faults or weak zones beneath the water layer. Even though conventional resistivity surveys in water-covered areas, in which electrodes are installed on the water bottom, do give high-resolution subsurface images, much time and effort is required to install electrodes. Therefore, an easier and more convenient method is sought to find the strike direction of the main zones of weakness, especially for reconnaissance surveys. In this paper, we investigate the applicability of the streamer resistivity survey method, which uses electrodes in a streamer cable towed by ship or boat, for delineating a fault zone. We do this through numerical experiments with models of water-covered areas. We demonstrate that the fault zone can be imaged, not only by installing electrodes on the water bottom, but also by using floating electrodes, when the depth of water is less than twice the electrode spacing. In addition, we compare the signal-to-noise ratio and resolving power of four kinds of electrode arrays that can be adapted to the streamer resistivity method. Following this numerical study, we carried out both conventional and streamer resistivity surveys for the planned tunnel construction site located at the Han River in Seoul, Korea. To obtain high-resolution resistivity images we used the conventional method, and installed electrodes on the water bottom along the planned route of the tunnel beneath the river. Applying a two-dimensional inversion scheme to the measured data, we found three distinctive low-resistivity anomalies, which we interpreted as associated with fault zones. To determine the strike direction of these three fault zones, we used the quick and convenient streamer resistivity.