• Molecules and Cells
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• v.41 no.1
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• pp.27-34
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• 2018

The cytoplasm in mammalian cells is a battlefield between the host and invading microbes. Both the living organisms have evolved unique strategies for their survival. The host utilizes a specialized autophagy system, xenophagy, for the clearance of invading pathogens, whereas bacteria secrete proteins to defend and escape from the host xenophagy. Several molecules have been identified and their structural investigation has enabled the comprehension of these mechanisms at the molecular level. In this review, we focus on one example of host autophagy and the other of bacterial defense: the autophagy receptor, NDP52, in conjunction with the sugar receptor, galectin-8, plays a critical role in targeting the autophagy machinery against Salmonella; and the cysteine protease, RavZ secreted by Legionella pneumophila cleaves the LC3-PE on the phagophore membrane. The structure-function relationships of these two examples and the directions of future research will be discussed.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.27.4-27.4
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• 2017

(1) The correlation between the mass of supermassive black holes (SMBHs) and the properties of their host galaxies suggests that SMBHs and host galaxies are closely linked in their formation and evolution. While the exact origin of their relationship is still under debate, theoretical models often invoke feedback from active galactic nuclei as a crucial mechanism for establishing the BH-host correlation. In the first part of my talk, I will present possible observational biases in the BH-host relation, and methods to overcome these biases. I will also report our efforts to find observational sign of the AGN feedback in high-z young luminous AGNs. (2) While intermediate-mass black hole (IMBH) is thought be cosmologically important class to understand the link between stellar mass black holes and SMBHs, it is extremely rare in the present-day Universe. In the second part of this talk, I will report a Gemini/GMOS-N IFU study of an ultraluminous X-ray source in NGC 5252, which is a possible candidate of an off-nuclear non-stellar black hole.

• The Plant Pathology Journal
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• v.20 no.1
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• pp.22-29
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• 2004

Many important horticultural and field crops are susceptible to virus infections or may possess a degree of resistance to some viruses, but become infected by others. Plant viruses enter cells through the presence of wounds, and replicate intracellularly small genomes that encode genes required for replication, cell-to-cell movement and encapsidation. There are numerous evidences from specific virus-host interactions to require the involvement of host factors and steps during viral replication cycle. However, viruses should deal with host defense responses either by general or specific mechanisms, targeting viral components or genome itself. On the other hand, the host plants have also adapted to defend themselves against viral attack by operating different lines of resistance responses. The defense-related interactions provide new insights into the complex molecular strategies for hosts for defense and counter-defense employed by viruses.

• Journal of the Korean Ceramic Society
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• v.26 no.4
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• pp.521-531
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• 1989

The dependence of the chemical durability of simulated waste glasses containing the simplified waste similar to the SRP waste on compositions of host glasses, amounts of waste loading, and kinds of leachants has been investigated as a basic study on the waste immobilization through vitrification. The maximum limit of the amount of waste loading for glassforming with the host sodium borosilicate glasses selected in this study was 50wt%. The chemical durability of waste glasses whose host glass belonged to the immiscible composition region was much higher than that of waste glasses whose host glass belonged to the miscible composition region. The former waste glass showed lower chemical durability in deionized and silicate waters than in brine, while the latter glass showed the lowest chemical durability in deionized and silicate waters than in brine, while the latter glass showed the lowest chemical durability in silicate water. It was also observed that the total leaching rates in brine were noticeably small in comparison with those in other solutions. The composition of the host borosilicate glass which was suitable for the treatment of the waste through vitrification was found to be 25 Na2O-5B2O3-70SiO2(wt.%).

• Journal of Plant Biology
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• v.28 no.4
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• pp.261-270
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• 1985

The portion of Cuscuta japonica haustorium which lies external to the host tissues, the upper haustorium, was investigated at the light- and electron-microscopic levels. The haustorium lightly contacted with the host was formed by the expansion of the epidermis and cortex of the stem at the contact side, and to have a group of meristematic cells within the haustorial cortex. When such a haustorium was closely contacted with the host, the meristematic region transformed into a primordial structure of the endophyte (endophyte primordium, EP) which may penetrate into the host tissues. EP consisted of the three kinds of cell group: dividing cells at the adaxial or proximal side; large, elongate cells (idioblasts) at the middle portion,; compressed cells at the abaxial or basal side. the idioblasts were characterized by the presence of large nucleus, dense cytoplasm, several small vacuoles, and abundant cell organelles including the multilamellar structures and cytosegresomes, and thus suggested to have a high metabolic activity. The features of the EP were discussed in relation to the possibility of the penetrating into host tissues.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.48.2-48.2
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• 2014

We present long-term optical to NIR data of the tidal disruption object, Swift J1644+57. The data were obtained with CQUEAN, UKIRT WFCAM observations. We analyze the morphology of the host galaxy of this object and decompose the bulge component using high resolution HST WFC3 images. We conclude that the host galaxy is bulge dominant. We also estimate the multi-band fluxes of the host galaxy through the light curves based on the long-term observational data. We fit the SED models to the multi-band fluxes of the host galaxy and determine its stellar mass. Finally, we estimate the mass of the central super massive black hole which is responsible for the tidal disruption event. The estimated stellar mass and black hole mass are ${\sim}10^{9.1}M_{\odot}$, ${\sim}10^{6.8}M_{\odot}$, respectively. We compare our results to other previous estimates.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.636-639
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• 2007

We have developed novel bipolar host materials, designed to have both electron transporting and hole transporting abilities, which show significant increase in luminance efficiency and decrease in driving voltage of green phosphorescent OLEDs. In case of the best host material, CheilGH-3, the driving voltage was decreased 27 % at a given constant luminance of $1000cd/m^2$. Also the luminance efficiency was enhanced 44 % and the power efficiency was almost doubled compared to the reference device using CBP as a host.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.9
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• pp.2373-2384
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• 1996

Connection caching technique is widely used to reduce the overhead incurred by frequency connection establishment in distributed computing environment using connection oriented protocol. We present an efficient connection caching scheme where we divide the system into several host groups and connection between the hosts in the same group is kept prior to others. In other words it makes the connection kept longer by sharing the connection use information between hosts in the same group. Every host group consists of hosts which have heavy intercommunication. And we present performance evaluation of the effect of host grouping upon connection caching and performance comparison of various grouping in several aspects includingmeanservice request interarrival time, mean service time, group size, grouping and type of group. Simulation results show that host grouping is effective in evrey performance criterion and proper grouping of hosts enhances the performance. We also present analysis results for Markov process model of our scheme which are consistent with the simulation results.

• Proceedings of the KIEE Conference
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• 1998.07g
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• pp.2473-2475
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• 1998

In this paper, we implemented RS232C serial communication by the 2 wires(Data,GND), and multiple access, by the applying Collision Sensing Multiple Access(CSMA) Protocol. Multiple access is implemented by assigning a unique ID to each controller. The multiple access control operation starts by sending a command packet from a host to another host and the command packet is composed of ID bytes of source and target host computer, data bytes and the check sum, byte. In host computer, after sending command packet, the collision from loop back data. If collision is detected, it means a command packet was collided with another command packet for another host. The packet communication of the controller enables the multiple acces of the controller through the common serial data link. The application of this serial communication through CSMA protocol and the usage of two wires, have an effect on saving the wires and convenient of layout work.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.475-476
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• 2015

We analyze the host galaxy of the tidal disruption object, Swift J1644+57, based on long-term optical to NIR data obtained with CQUEAN and UKIRT WFCAM observations. We decompose the bulge component using high resolution HST WFC3 images. We conclude that the host galaxy is bulge dominant. We investigate optical to NIR light curves and estimate the multi-band fluxes of the host galaxy. We fit spectral energy distribution (SED) models in order to determine the stellar mass. Finally, we estimate the mass of the black hole in the center of the host galaxy based on several scale relations.