We present recent observation results of Sgr A* at millimeter obtained with VLBI arrays in Korea and Japan.

7 mm monitoring of Sgr A* is part of our AGN large project. The results at 7 epochs during 2013-2014, including high resolution maps, flux density and two-dimensional size measurements are presented. The source shows no significant variation in flux and structure related to the G2 encounter in 2014. According to recent MHD simulations by kawashima et al., flux and magnetic field energy can be expected to increase several years after the encounter; We will keep our monitoring in order to test this prediction.

Astrometric observations of Sgr A* were performed in 2015 at 7 and 3.5 millimeter simultaneously. Source-frequency phase referencing was applied and a combined ”core-shift” of Sgr A* and a nearby calibrator was measured. Future observations and analysis are necessary to determine the core-shift in each source.

The Ultra-Fast Flash Observatory (UFFO), which will be launched onboard theLomonosov spacecraft, contains two crucial instruments: UFFO BurstAlert & Trigger Telescope (UBAT) for detection and localization of Gamma-Ray Bursts(GRBs) and the fast-response Slewing Mirror Telescope (SMT) designed for the observationof the prompt optical/UV counterparts. Here we discuss the in-space calibrations of theUBAT detector and SMT telescope. After the launch, the observations of the standard X-raysources such as pulsar in Crab nebula will provide data for necessary calibrations ofUBAT. Several standard stars will be used for the photometric calibration of SMT. Thecelestial X-ray sources, e.g. X-ray binaries with bright optical sourcesin their close angular vicinity will serve for the cross-calibration of UBAT and SMT.

The Ultra-Fast Flash Observatory (UFFO) Pathfinder for Gamma-Ray Bursts (GRBs) consistsof two telescopes. The UFFO Burst Alert & Trigger Telescope (UBAT) handles thedetection and localization of GRBs, and the Slewing Mirror Telescope (SMT) conducts themeasurement of the UV/optical afterglow. UBAT is equipped with an X-ray detector, analogand digital signal readout electronics that detects X-rays from GRBs and determines thelocation. SMT is equipped with a stepping motor and the associated electronics to rotatethe slewing mirror targeting the GRBs identified by UBAT. First the slewing mirror pointsto a GRB, then SMT obtains the optical image of the GRB using the intensified CCD and itsreadout electronics. The UFFO Data Acquisition system (UDAQ) is responsible for theoverall function and operation of the observatory and the communication with the satellitemain processor. In this paper we present the design and implementation of the electronicsof UBAT and SMT as well as the architecture and implementation of UDAQ.

The UFFO (Ultra-Fast Flash Observatory) is a GRB detector on board the Lomonosovsatellite, to be launched in 2013. The GRB trigger is provided by an X-ray detector,called UBAT (UFFO Burst Alarm & Trigger Telescope), which detects X-rays from the GRBand then triggers to determine the direction of the GRB and then alerts the Slewing MirrorTelescope (SMT) to turn in the direction of the GRB and record the optical photon fluxes.This report details the calibration of the two components: the MAPMTs and the YSO crystalsand simulations of the UBAT. The results shows that this design can observe a GRB within afield of view of ±35° and can trigger in a time scale as short as 0.2 – 1.0 safter the appearance of a GRB X-ray spike.

The Ultra-Fast Flash Observatory (UFFO) is a space observatory for optical follow-ups ofgamma ray bursts (GRBs), aiming to explore the first 60 seconds of GRBs optical emission.UFFO is utilized to catch early optical emissions from GRBs within few sec after triggerusing a Gimbal mirror which redirects the optical path rather than slewing entirespacecraft. We have developed a 15 cm two-axis Gimbal mirror stage for the UFFO-Pathfinderwhich is going to be on board the Lomonosov satellite which is to be launched in 2013. Thestage is designed for fast and accurate motion with given budgets of 3 kg of mass and 3Watt of power. By employing stepping motors, the slewing mirror can rotate faster than 15deg/sec so that objects in the UFFO coverage (60 deg × 60 deg) can be targeted in~1 sec. The obtained targeting resolution is better 2 arcmin using a close-loopcontrol with high precision rotary encoder. In this presentation, we will discuss detailsof design, manufacturing, space qualification tests, as well as performance tests.

Hypermucoviscous (HV) isolates of Klebsiella pneumoniae have been linked to virulence potential in experimental infections. We examined 33 isolates of K. pneumoniae from patients with bacteraemia for the HV phenotype on agar culture, and determined their virulence potential by screening for capsular (K) serotype by polymerase chain reaction and the presence of seven virulence factor genes. Fourteen (42·4%) isolates expressed the HV phenotype and 11 of these were serotype K1 or K2; these serotypes were not identified in HV-negative isolates. The genes rmpA, rmpA2, aerobactin, wabG and allS were significantly more frequent in HV than non-HV isolates. Multilocus sequence typing identified 21 sequence types (ST), eight of which were found in HV-positive isolates and the clonal relatedness of isolates of the most frequent types (ST23 and ST11) from different hospitals was confirmed by pulsed-field gel electrophoresis. The HV phenotype was more associated with community-acquired infection with a lower frequency of fatal underlying illness, but with significantly more focal infections, notably liver abscesses. Clinicians should be aware of such clinical impacts of the HV phenotype.

The incidence and severity of Clostridium difficile infections (CDI) have increased in Western countries. However, there are limited data regarding the epidemiology of CDI in Eastern countries. This nationwide study was conducted in 17 hospitals to determine temporal trends in CDI incidence (from 2004 to 2008) in South Korea. The total incidence of CDI in Korea was 1·7 cases/1000 adult admissions in 2004, and 2·7/1000 cases in 2008 (P = 0·028). When analysing the clinical features of 1367 CDI patients diagnosed in 2008, oral metronidazole was effective as a first-line treatment for CDI (61·9%). Relapse rate was 8·9% and complicated CDI was only observed in 3·6%. The incidence of CDI increased significantly in Korea from 2004 to 2008. Although the clinical features were milder than in Western countries, the increasing burden of CDI needs ongoing surveillance systems.

The Ultra-Fast Flash Observatory (UFFO) is a space mission to detect the early moments of an explosion from Gamma-ray bursts (GRBs), thus enhancing our understanding of the GRB mechanism. It consists of the UFFO Burst & Trigger telescope (UBAT) for the recognition of GRB positions using hard X-ray from GRBs. It also contains the Slewing Mirror Telescope (SMT) for the fast detection of UV-optical photons from GRBs. It is designed to begin the UV-optical observations in less than a few seconds after the trigger. The UBAT is based on a coded-mask X-ray camera with a wide field of view (FOV) and is composed of the coded mask, a hopper and a detector module. The SMT has a fast rotatable mirror which allows a fast UV-optical detection after the trigger. The telescope is a modified Ritchey-Chrétien telescope with the aperture size of 10 cm diameter, and an image intensifier readout by CCD. The UFFO pathfinder is scheduled to launch into orbit on 2012 June by the Lomonosov spacecraft. It is a scaled-down version of UFFO in order to make the first systematic study of early UV/optical light curves, including the rise phase of GRBs. We expect UBAT to trigger ~44 GRBs/yr and expect SMT to detect ~10 GRBs/yr.

Thyroid hemiagenesis is a rare abnormality in which one thyroid lobe fails to develop. Most of the patients diagnosed have an associated thyroid disease. We report the case of a 32-year-old woman who presented with a left thyroid mass which had been gradually increasing in size over a period of two years. A thyroid scan revealed the absence of the right thyroid lobe and isthmus, and a hypoactive nodule was evident in the lower pole of the left lobe. Ultrasonography confirmed the right lobe and the isthmus agenesis. The operative findings confirmed hemiagenesis of the right lobe and nodular hyperplasia in the left lobe.

The purpose of this report is to present a patient with hemiagenesis of the thyroid gland who concomitantly had nodular hyperplasia; we also stress the importance of pre-operative differentiation between benign lesions and malignancy in order to aid critical decision making and to facilitate preservation of thyroid function if possible.

In this paper, we present the results of Plasma Enhanced Chemical Vapor Deposition gate oxide (SiO2) integrity on ELC (excimer laser crystallized), MILC (metal induced lateral crystallized) and SPC (solid phase crystallized) polysilicon films. We observed that gate oxide strength of poly Si TFT strongly depends on the crystallization method for the active silicon layer. In the case of ELC films, asperities on the silicon surface reduce the SiO2 breakdown field significantly. The metallic contaminants in MILC films are responsible for a deleterious impact on gate oxide integrity. Among the three cases, the SiO2 breakdown field was the highest for the SPC silicon films. The breakdown fields at the 50% failure points in Weibull plots for the ELC, MILC and SPC cases were 5.1MV/cm, 6.2MV/cm, 8.1MV/cm, respectively. We conclude that the roughness and metallic contamination of the poly Si films are the main factors that cause en-hanced breakdown of SiO2 films.

Vertically aligned carbon nanorods and multi walled carbon nanotubes (MWNTs) were synthesized by electron cyclotron resonance chemical vapor deposition (ECR-CVD) on Ni- coated glass substrates with the RF-self biasing of –100 and –200 V, respectively. High-resolution transmission electron microscopy indicated that the distance between adjacent graphene layers of carbon nanorods is much larger than that of well-graphitized MWNTs. In electron-energy-loss spectra, the energy of π+σ plasmon peak for the carbon nanorod shifts towards lower value of 23.8 eV, by comparison with the well-graphitized MWNT at 25.5 eV. In addition, the π palsmon peak at 6 eV is clearly defined for the well-graphitized MWNT, but not seen for the carbon nanorod. X-ray photoelectron spectroscopy also showed that the delocalization of π electrons gets more pronounced with the structural evolvement from the carbon nanorod to the well-graphitized MWNT. Therefore, it is suggested that ionic bombardment can provide sufficient internal energy for dehydrogenation from hydrocarbon molecules, and thus, well-graphitized MWNTs could be grown even at low temperatures.

One of the objectives of the present study was to investigate whether 1 % conjugated linoleic acid (CLA) in the diet reduced tumour incidence in the colon of 1,2-dimethylhydrazine (DMH)-treated rats. Colon cancer was induced by injecting 6-week-old, male, Sprague–Dawley rats with 15 mg/kg DMH twice per week for 6 weeks. They were fed either 1 % CLA or a control diet ad libitum for 30 weeks. Dietary CLA significantly decreased colon tumour incidence (P<0·05). Our second objective was to investigate whether apoptosis in the colon mucosa of DMH-treated rats was affected by the amount of dietary CLA and whether the changes in apoptosis were related to those in fatty acid-responsive biomarkers. For this purpose, rats were killed after being fed a diet containing 0 %, 0·5 %, 1 % or 1·5 % CLA for 14 weeks. CLA was undetected in the mucosa of rats fed the 0 % CLA diet and increased to 5·9 mg/g phospholipid in rats fed the 0·5 % diet. The apoptotic index estimated by the terminal deoxynucleotidyl transferase-mediated dUTP nick and labelling technique was increased by 251 % and the 1,2-diacylglycerol content was decreased by 57 % in rats fed 0·5 % CLA. No further changes in these variables were observed when CLA in the diet was raised to 1·0 % or 1·5 %. However, dietary CLA decreased mucosal levels of prostaglandin E2, thromboxane B2 and arachidonic acid in a dose-dependent manner. The present data indicate that dietary CLA can inhibit DMH-induced colon carcinogenesis by mechanisms probably involving increased apoptosis.

A new structure of triode type field emission displays based on single-walled carbon nanotube emitters is demonstrated. In this structure, gate electrodes are situated under cathode electrodes with an in-between insulating layer, so called under-gate type triode. Electron emission from the carbon nanotube emitters is modulated by changing gate voltages. A threshold voltage is approximately 70 V at the anode bias of 275 V.

We have grown vertically aligned carbon nanotubes on a large area of Co-Ni codeposited Si substrates by thermal chemical vapor deposition using C2H2 gas. The carbon nanotubes grown by the thermal chemical vapor deposition are multi-wall structure, and the wall surface of nanotubes is covered with defective graphite sheets or carbonaceous particles. The carbon nanotubes range from 50 to 120 nm in diameter and about 130 μm in length at 950 °C. Steric hindrance between nanotubes at an initial stage of the growth forces nanotubes to align vertically. The turn-on voltage was about 0.8 V/μm with a current density of 0.1 μA/cm2 and emission current reveals the Fowler-Nordheim mode.

We present performance results of 4-inch full-color field emission display (FED) devices which are constructed by using Spindt type arrays with 80,000,000 Mo-metal tips, spacers, uniquely-developed low voltage color phosphors. Spindt type microtips with less than 1.1 urn in hole size are fabricated using a total internal reflection (TIR) holographic lithograpy method. Each color phosphor is electrophoretically deposited on the ITO line. The spacer which is screen-printed is characterized by a 3-dimentional surface analysis system. Electron emission pattern and luminance test of each pixel without cross talk are analyzed under different gate voltages. In addition, the total pressure and residual gas distributions inside the panel are investigated at various gap sizes between the cathode and anode plates.

We present a new analytical model of amorphous silicon thin-film transistor (a-Si TFT) suitable for circuit simulators such as SPICE. The effects of localized gap state distributions of a-Si as well as temperatures on the a-Si TFT performances have been fully considered in the presented model. The parameters used in SPICE, such as transconductance, channel-length modulation, and power factor of source-drain current, are evaluated from the measured current-voltage and capacitance-voltage characteristics by employing the proposed extraction method. It has been found out that the analytical model is in good agreement with experimental data at both room temperature and elevated temperature and successfully implemented in a widely used circuit simulator.