• The Korean Journal of Physiology and Pharmacology
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• v.16 no.1
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• pp.17-24
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• 2012

The hypothalamus-pituitary-adrenocortex (HPA) axis is the central mediator of the stress response. The supramammillary (SuM) region is relatively unique among the hypothalamic structures in that it sends a large, direct projection to the hippocampal formation. It has been shown that mild stress could activate the SuM cells that project to the hippocampus. However, the role of these cell populations in modulating the stress response is not known. The present study examined the effect of stress on different populations of SuM cells that project to the hippocampus by injecting the fluorescent retrograde tracer, fluorogold (FG), into the hippocampus and utilizing the immunohistochemistry of choline acetyltransferase (ChAT), corticotrophin releasing factor (CRF), serotonin (5-HT), glutamate decarboxylase (GAD), tyrosine hydroxylase (TH) and NADPH-d reactivity. Immobilization (IMO) stress (2 hr) produced an increase in the expression of ChAT- immunoreactivity, and tended to increase in CRF, 5-HT, GAD, TH-immunoreactivity and nitric oxide (NO)-reactivity in the SuM cells. Fifty-three percent of 5-HT, 31% of ChAT and 56% of CRF cells were double stained with retrograde cells from the hippocampus. By contrast, a few retrogradely labeled cells projecting to the hippocampus were immunoreactive for dopamine, ${\gamma}$-aminobutyric acid (GABA) and NO. These results suggest that the SuM region contains distinct cell populations that differentially respond to stress. In addition, the findings suggest that serotonergic, cholinergic and corticotropin releasing cells projecting to the hippocampus within the SuM nucleus may play an important role in modulating stress-related behaviors.

• Journal of Broadcast Engineering
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• v.15 no.3
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• pp.332-345
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• 2010

A unified image enhancement method is proposed for high-resolution image which based on color constancy and histogram equalization using edge region. To speed up the method, smaller image is used when parameters of color constancy and histogram equalization are determined. In the color constancy process, nth-derivative of gaussian is applied to x and y axis separately in order to estimate the color of the illumination rapidly. In the histogram equalization process, the histogram obtained from near-edge region is used for the histogram equalization. In the experiments, high-resolution images taken by digital camcorder are used for verifying the performance of the proposed method.

• Journal of KIISE:Databases
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• v.35 no.4
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• pp.345-355
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• 2008

SIFT is popularly used in computer vision application such as object recognition, motion tracking, and 3D reconstruction among various shape descriptors. However, it is not easy to apply SIFT into the image similarity search as it is since it uses many high dimensional keypoint vectors. In this paper, we present a SIFT based image similarity search method using an edge image pyramid and an interesting region detection. The proposed method extracts keypoints, which is invariant to contrast, scale, and rotation of image, by using the edge image pyramid and removes many unnecessary keypoints from the image by using the hough transform. The proposed hough transform can detect objects of ellipse type so that it can be used to find interesting regions. Experimental results demonstrate that the retrieval performance of the proposed method is about 20% better than that of traditional SIFT in average recall.

• Journal of the Korea Society of Computer and Information
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• v.12 no.3
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• pp.105-113
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• 2007

In this paper, an image segmentation method which is based on edge salience map and region merging is presented. The edge salience map is calculated by combining a texture edge map with a color edge map. The texture edge map is computed over multiple spatial orientations and frequencies by using Gabor filter. A color edge is computed over the H component of the HSI color model. Then the Watershed transformation technique is applied to the edge salience map to and homogeneous regions where the dissimilarity of color and texture distribution is relatively low. The Watershed transformation tends to over-segment images. To merge the over-segmented regions, first of all, morphological operation is applied to the edge salience map to enhance a contrast of it and also to find mark regions. Then the region characteristics, a Gabor texture vector and a mean color, in the segmented regions is defined and regions that have the similar characteristics, are merged. Experimental results have demonstrated the superiority in segmentation results for various images.

• The Journal of the Korea Contents Association
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• v.5 no.6
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• pp.87-96
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• 2005

In this paper, a selective visual attention module based on motion stimuli is introduced for the purpose of detecting ROI(region of interest) or FOA(focus of attention) in motion pictures. Analysis of motion fields in our approach is in direct contrast to some of the previous studies of selective visual attention module. Motion that presents temporal visual saliency in an aspect between two successive frames is analyzed based on psychological studies in 'DORF(double opponent receptive fields)' and 'NF(noise filtration)' in MT(middle temporal cortex). Analyzed results are integrated based on the theory of 'motion integration' in MT to obtain a single conspicuous region. Experiments through a human subjective evaluation showed generally accepted results.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.1
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• pp.38-50
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• 1999

Currently many devices reproduce electronic images in the various ways. However the color that is reproduced in any device is different from the original color due to the difference in the gamut between devices. In this paper, an image dependent gamut mapping method is proposed. This method clips the chroma with compensating for the change of lightness caused by the lightness scaling. The anchor point, which is the center point in the mapping, is set as a lower point by the proposed method than a point by the conventional mapping method. This reduces the color difference between point. In addition, to heighten the color contrast on the constant hue, the different two mapping methods are applied to the printer gamut which is divided in two region, bright region and dark region. Consequently, the printer output image was highly consistent with the corresponding monitor image.

• Structural Engineering and Mechanics
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• v.25 no.4
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• pp.481-500
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• 2007

The dynamic instability of doubly curved panels, subjected to non-uniform tensile in-plane harmonic edge loading $P(t)=P_s+P_d\;{\cos}{\Omega}t$ is investigated. The present work deals with the problem of the occurrence of combination resonances in contrast to simple resonances in parametrically excited doubly curved panels. Analytical expressions for the instability regions are obtained at ${\Omega}={\omega}_m+{\omega}_n$, (${\Omega}$ is the excitation frequency and ${\omega}_m$ and ${\omega}_n$ are the natural frequencies of the system) by using the method of multiple scales. It is shown that, besides the principal instability region at ${\Omega}=2{\omega}_1$, where ${\omega}_1$ is the fundamental frequency, other cases of ${\Omega}={\omega}_m+{\omega}_n$, related to other modes, can be of major importance and yield a significantly enlarged instability region. The effects of edge loading, curvature, damping and the static load factor on dynamic instability behavior of simply supported doubly curved panels are studied. The results show that under localized edge loading, combination resonance zones are as important as simple resonance zones. The effects of damping show that there is a finite critical value of the dynamic load factor for each instability region below which the curved panels cannot become dynamically unstable. This example of simultaneous excitation of two modes, each oscillating steadily at its own natural frequency, may be of considerable interest in vibration testing of actual structures.

• Proceedings of the Botanical Society of Korea Conference
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• 1987.07a
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• pp.261-282
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• 1987

Plants store a significant amount of their nitrogen, sulfur and carbon reserves as storage proteins in seed tissues. The major proteins present in rice seeds are the glutelins. Glutelins are initially synthesized at 4-6 days postanthesis and deposited into protein bodies via Golgi apparatus. Based on nucleic acid sequences and Southern blot analysis, the three isolated glutelin genomic clones were representative members of three gene subfamilies each containing 5 to 8 copies. A comparison of DNA sequences displayed by relevant regions of these genomic clones showed that two subfamilies, represented by clones, Gt1 and Gt2, were closely, related and probably evolved by more recent gene duplication events. The 5' flanking and coding sequences of Gt1 and Gt2 displayed at least 87% homolgy. In contrast, Gt3 showed little or no homolgy in the 5' flanking sequences upstream of the putative CAAT boxes and exhibited significant divergence in all other portions of the gene. Conserved sequences in the 5' flanking regions of these genes were identified and discussed in light of their potential regulatory role. The derived primary sequences of all three glutelin genomic clones showed significant homology to the legume 11S storage proteins indicating a common gene origin. A comparison of the derived glutelin primary sequences showed that mutations were clustered in three peptide regions. One peptide region corresponded to the highly rautable hypervariable region of legume peptide region of legume 11S storage proteins, a potential target area for protein modification. Expression studies indicated that glutelin mRNA transcripts are differentially accumulated during endosperm development. Promoterss of Gt2 and Gt3 were functional as they direct transient expression of chloramphenicol acetyltransferase in cultured plant cell.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.110.2-110.2
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• 2012

We investigate a cool loop and a dark lane over a limb active region on 2007 March 14 by the Hinode/EUV Imaging Spectrometer (EIS). The cool loop is clearly seen in the EIS spectral lines formed at the transition region temperature (log T = 5.8). The dark lane is characterized by an elongated faint structure in coronal spectral lines (log T = 5.8 - 6.1) and rooted on a bright point. We examine their electron densities, Doppler velocities, and non-thermal velocities as a function of distance from the limb using the spectral lines formed at different temperatures (log T = 5.4 - 6.4). The electron densities of the cool loop and the dark lane are derived from the density sensitive line pairs of Mg VII, Fe XII, and Fe XIV spectra. Under the hydrostatic equilibrium and isothermal assumption, we determine their temperatures from the density scale height. Comparing the scale height temperatures to the peak formation temperatures of the spectral lines, we note that the scale height temperature of the cool loop is consistent with a peak formation temperature of the Mg VII (log T = 5.8) and the scale height temperature of the dark lane is close to a peak formation temperature of the Fe XII and Fe XIII (log T = 6.1 - 6.2). It is interesting to note that the structures of the cool loop and the dark lane are most visible in these temperature lines. While the non-thermal velocity in the cool loop slightly decreases (less than 7 km $s^{-1}$) along the loop, that in the dark lane sharply falls off with height. The variation of non-thermal velocity with height in the cool loop and the dark lane is contrast to that in off-limb polar coronal holes which are considered as source of the fast solar wind. Such a decrease in the non-thermal velocity may be explained by wave damping near the solar surface or turbulence due to magnetic reconnection near the bright point.

• 한국균학회소식:학술대회논문집
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• 2006.10a
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• pp.24-28
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• 2006

Author have studies lichen flora of the most important ice-free areas of Continental Antarctic: Bunger Hills, and the vicinity of Prudz Bay (Larsemann Hills, and Radok Lake in Prince Charles Mountains). Totally 44 lichen species from 22 genera were reported for Bunger Hills and 50 lichen species from 22 genera and 10 families: Acarosporaceae, Lecanoraceae, Lecideaceae, Parmeliaceae, Pertusariaceae, Physciaceae, Rhizocarpaceae, Stereocaulaceae, Theloschistaceae, and Umbilicariaceaewere reported for the Prudz Bay Region. 20 lichen species were found in the region for the first time. Phytogeographic analysis indicated a relatively high proportion of species with bipolar distribution - about 50% of recorded lichen species. About 30% of lichens normally don't extend into maritime zone occurring in continental Antarctic only. The most common lichen families in the region are Buelliaceae, Lecanoraceae and Teloschistaceae. The water supply and not a temperature is the critical factor for lichens in the Continental Antarctic. Moisture appears to be supplied for lichens not only from snow-melt water but mainly from air. In Maritime Antarctic, due to high air humidity macrolichens form communities everywhere (Himantormia, Usnea and Umbilicaria). In oases of Continental Antarctic extensive sites are lacking in lichen cover, even if the ground is normally snow free. Lichens occur at humid sites with moisture which were brought by winds over the ice cap and poorly developed or absent in dry areas. Of particular significance for lichens are substrate characteristics, animals influence and salinity brought by wind in coastal areas. Most rich lichen vegetation developed in oases around nests of snow petrels, where the melt water is enriched by nutrients. In contrast, the most pure vegetation is on mobile sand and gravel and in salted coastal habitats.