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We have done a CO(1-0) imaging survey of the central regions of nearby spiral galaxies using the Nobeyama and Owens Valley Millimeter Arrays. The survey aims to reveal the nuclear gas properties in normal galaxies that have been paid relatively little attention compared to Seyferts, mergers, and ultraluminous IRAS galaxies. The sample consists of 20 galaxies that meet the following criteria: (1) i < 70° (2) δ > +5° (3) ICOdV ≥ 10 K(T∗A)km s−1 in the FCRAO Extragalactic CO Survey (4) no evidence of significant perturbation (e.g. merging). No selection was made on the basis of nuclear activity or IRAS data. The average distance of the galaxies is 15 Mpc and the average linear resolution is 300 pc.
Zizina emelina (de l'Orza) is listed on Japan's Red Data List as an endangered species because of loss of its principal food plant and habitat. We compared parts of the mitochondrial and nuclear genes of this species to investigate the level of genetic differentiation among the 14 extant populations. We also examined infection of the butterfly with the bacterium Wolbachia to clarify the bacterium's effects on the host population's genetic structure. Mitochondrial and nuclear DNA analyses revealed that haplotype composition differed significantly among most of the populations, and the fixation index FST was positively correlated with geographic distance. In addition, we found three strains of Wolbachia, one of which was a male killer; these strains were prevalent in several populations. There was linkage between some host mitochondrial haplotypes and the three Wolbachia strains, although no significant differences were found in a comparison of host mitochondrial genetic diversity with nuclear genetic diversity in Wolbachia-infected or -uninfected populations. These genetic analyses and Wolbachia infection findings show that Z. emelina has little migratory activity and that little gene flow occurs among the current populations.
The HYPER-II device has been constructed in Kyushu University to investigate the flow structure formation in an ion-unmagnetized plasma, which is an intermediate state of plasma and consists of unmagnetized ions and magnetized electrons. High density plasmas are produced by electron cyclotron resonance heating, and the flow field structure in an inhomogeneous magnetic field is investigated with a directional Langmuir probe method and a laser-induced fluorescence method. The experimental setup has been completed and the diagnostic systems have been installed to start the experiments. A set of coaxial electrodes will be introduced to control the azimuthal plasma rotation, and the effect of plasma rotation to generation of rectilinear flow structure will be studied. The HYPER-II experiments will clarify the overall flow structure in the inhomogeneous magnetic field and contribute to understanding characteristic feature of the intermediate state of plasma.
Monitor of All-sky X-ray Image (MAXI) on board International Space Station is capable of
observing gamma-ray bursts (GRBs) and sending notices of GRBs or other transient events,
using real time connection to the ground. MAXI observed 32 GRBs or short X-ray transients
as of the end of September 2012. Among them, eleven events were simultaneously detected by
other satellites. The observed rate of the MAXI GRBs is about one event per month. This
rate is comparable to a past observation with larger effective area and larger field of
view. The fact indicates that MAXI has better sensitivity to observe GRBs because of low
background. The distribution of the spectral hardness of MAXI GRBs is similar to the
results of a past instrument, which is sensitive to similar energy range.
We have employed a 2.45 GHz electron cyclotron resonance (ECR) plasma source to deposit single-crystal thin films of titanium nitride onto MgO substrates of (100) orientation. During deposition the ECR plasma beam delivering a mixture of excited species of molecular and atomic nitrogen ions, strikes a substrate while an electron beam deposits on the same substrate species of titanium. We have studied the formation of films at substrate temperatures of 200, 400, and 600°C, as well as at room temperature. X-Ray diffraction (XRD) revealed that a cubic Bl phase of titanium nitride forms predominantly at all the temperatures explored. Both channeling and Rutherford backscattering spectroscopy (RBS) showed epitaxial layers forming at the temperature as low as 400°C. The minimum relative backscattering yield, χmin decreased as the temperature increased, with the best result of 7.3% obtained for the film deposited at 600°C. Biasing the substrates with either negative or positive voltage at room temperature directly affects film crystallography.
Mullite (3Al2O3·2SiO2) has a low thermal expansion coefficient and a low dielectric constant making it a favorable material for substrate applications. Sintering of pure mullite ceramics is difficult, however, even above 1700°C. Thus, mullite-glass ceramics containing glass additives (Al2O3-MgO-SiO2 glass) which could be sintered at about 1600°;C were fabricated and their properties were investigated. The ternary system diagram of Al2O3-MgO-SiO2 shows that high SiO2 content glass depos its cristobalite at 200 to 270°C, which causes a substantial volume change, resulting in ceramic substrate cracking. Therefore it is particularly important to prevent crystallization of cristobalite from the glass phase in mullite-glass ceramics. The glass phase softens or partially fuses above 1600°C, and cristobalite formation in the glass phase occurs in the cooling process during firing. In order to obtain good substrates of mullite-glass ceramics, a higher temperature for sintering and faster cooling rate after firing are preferable. Analytical results by X-ray, SEM and EPMA show that mullite dissolves in the glass phase at a higher sintering temperature and more mullite crystallizes in the cooling process with a lower rate. The content of Al2O3 in the glass phase, therefore, increases with the increased sintering temperature and cooling rate, which may restrain crystallization of cristobalite. By adjusting of the composition of mullite and glass phase, mullite-glass ceramics with low dielectric constant (5.9), thermal expansion coefficient (3.5×10−6/°C) close to that of silicon chips, and high bending strength (210MPa) have been developed. These substrates made of mullite-glass ceramics are suitable for mounting silicon devices of computer processors.
This paper reviews 22 cases of minor salivary gland carcinoma of the oral cavity or oropharynx which were treated at Kurume University Hospital between 1976 and 2005. Minor salivary gland carcinoma was observed in eight of 362 patients with cancer of the oral cavity (2 per cent), and in 14 of 275 patients with cancer of the oropharynx (5 per cent). The five-year and 10-year survival rates of patients with oropharyngeal minor salivary gland carcinoma were 90 per cent. No statistically significant difference was observed between survival rates for oropharyngeal minor salivary gland carcinoma and for oropharyngeal squamous cell carcinoma (p = 0.06). The five- and 10-year survival rates of patients with oral cavity minor salivary gland carcinoma were 75 and 37 per cent, respectively. No statistically significant difference was observed between survival rates for oral cavity minor salivary gland carcinoma and oral cavity squamous cell carcinoma.
Patients' survival results correlated well with the clinical stage of their lesions. A significant difference in survival was observed, comparing stage IV with stages I, II and III (p = 0.04). In contrast, no significant relationship was found between either survival and tumour type or survival and treatment. Adjuvant therapy is recommended for patients with grade III adenoid cystic carcinoma with perineural infiltration or intravascular infiltration.
Legionnaires' disease (LD) is a major cause of severe community-acquired pneumonia but the source and mode of transmission are not always apparent, especially in sporadic cases. We hypothesized that LD can be acquired from the air-conditioning systems of motor cars. Swabs were taken from the evaporator compartments of the air-conditioning system of scrapped cars. Healthy subjects who were mainly employees of regional transportation companies were tested for antibody to Legionella pneumophila serogroups 1–6; they also completed a questionnaire. Legionella species were detected in 11/22 scrapped cars by the loop-mediated isothermal amplification method. The prevalence of microplate agglutination titres ⩾1:32 was significantly higher in subjects who sometimes used car air-conditioning systems. Although we did not prove a direct link between Legionella spp. in the car evaporator and LD, our findings point to a potential risk of car air-conditioning systems in LD, which needs further investigation.
Atacama Submillimeter Telescope Experiment (ASTE) is a joint project between Japan and Chile for installing and operating a 10 m high precision telescope in the Atacama Desert in order to explore the southern sky through the submillimeter wavelength. We have achieved an accuracy of 19 μm (rms) for the main reflector surface and a stable radio pointing accuracy of about 2 arcsec (rms). A 350 GHz cartridge type SIS mixer receiver achieves good performance with a typical system noise temperature of 150 ~ 250 K in DSB and a main beam efficiency of 0.6 ~ 0.7 during winter nights.
A large scale CO(3-2) imaging survey of nearby galaxies using ASTE is now in progress. One of our goals is to compare our wide area CO(3-2) images with existing CO(1-0) data as well as distributions of massive star formation tracers (i.e., Hα and radio continuum emission) in order to understand the physical mechanism which controls the global star formation properties such as star formation efficiency. Initial CO(3-2) maps of some sample galaxies (M 83, NGC 604 in M 33, NGC 1672, & NGC 7130) are reported.
We have performed CO(J=3−2) emission observations with the Atacama Submillimeter Telescope Experiment (ASTE) toward the 5′ × 5′ (or 6.6 × 6.6 kpc at the distance D = 4.5 Mpc) region of the nearby barred spiral galaxy M 83. We successfully resolved the major structures, i.e., the nuclear starburst region, bar, and inner spiral arms in CO(J=3−2) emission at a resolution of 22'' (or 480 pc), showing a good spatial coincidence between CO(J=3−2) and 6 cm continuum emissions.
From a comparison of CO(J=3−2) data with CO(J=1−0) intensities measured with Nobeyama 45-m telescope, we found that the radial profile of CO(J=3−2)/CO(J=1−0) integrated intensity ratio R3−2/1−0 is almost unity in the central region (r<0.25 kpc), whereas it drops to a constant value, 0.6–0.7, in the disk region. The radial profile of star formation efficiencies (SFEs), determined from 6 cm radio continuum and CO(J=1−0) emission, shows the same trend as that of R3−2/1−0. At the bar-end (r ~ 2.4 kpc), the amounts of molecular gas and the massive stars are enhanced when compared with other disk regions, whereas there is no excess of R3−2/1−0 and SFE in that region. This means that a simple summation of the star forming regions at the bar-end and the disk cannot reproduce the nuclear starburst of M 83, implying that the spatial variation of the dense gas fraction traced by R3−2/1−0 governs the spatial variation of SFE in M 83.
Thirty rabies virus isolates from cows and vampire bats from different regions of São Paulo State, Southeastern Brazil and three rabies vaccines were studied genetically. The analysis was based on direct sequencing of PCR-amplified products of 600 nucleotides coding for the amino terminus of nucleoprotein gene. The sequences were checked to verify their genealogical and evolutionary relationships and possible implication for health programmes. Statistical data indicated that there were no significant genetic differences between samples isolated from distinct hosts, from different geographical regions and between samples collected in the last two decades. According to the HKA test, the variability observed in the sequences is probably due to genetic drift. Since changes in genetic material may produce modifications in the protein responsible for immunogenicity of virus, which may eventually cause vaccine failure in herds, we suggest that continuous efforts in monitoring genetic diversity in rabies virus field strains, in relation to vaccine strains, must be conducted.