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The neutral beam (NB) fast ion confinement in the Large Helical Device (LHD) is studied for several full field (
) magnetic configurations by a combination of neutron measurement and simulations. To investigate the NB fast ion confinement, we have performed a series of short-pulse NB injection experiments. The experiment results are analysed by the integrated code TASK3D-a. From this investigation, the effective particle diffusion coefficients of the tangential and perpendicular NBs are approximately
in the standard configuration. It is clarified that the NB fast ion confinement improves when the plasmas are shifted inward. Moreover, it is also found that the simulation, which considers the deuteron dilution effect due to the presence of impurity ions, can describe a neutron emission rate consistent with the measurement.
Measurements in the infrared wavelength domain allow direct assessment of the physical state and energy balance of cool matter in space, enabling the detailed study of the processes that govern the formation and evolution of stars and planetary systems in galaxies over cosmic time. Previous infrared missions revealed a great deal about the obscured Universe, but were hampered by limited sensitivity.
SPICA takes the next step in infrared observational capability by combining a large 2.5-meter diameter telescope, cooled to below 8 K, with instruments employing ultra-sensitive detectors. A combination of passive cooling and mechanical coolers will be used to cool both the telescope and the instruments. With mechanical coolers the mission lifetime is not limited by the supply of cryogen. With the combination of low telescope background and instruments with state-of-the-art detectors SPICA provides a huge advance on the capabilities of previous missions.
SPICA instruments offer spectral resolving power ranging from R ~50 through 11 000 in the 17–230 μm domain and R ~28.000 spectroscopy between 12 and 18 μm. SPICA will provide efficient 30–37 μm broad band mapping, and small field spectroscopic and polarimetric imaging at 100, 200 and 350 μm. SPICA will provide infrared spectroscopy with an unprecedented sensitivity of ~5 × 10−20 W m−2 (5σ/1 h)—over two orders of magnitude improvement over what earlier missions. This exceptional performance leap, will open entirely new domains in infrared astronomy; galaxy evolution and metal production over cosmic time, dust formation and evolution from very early epochs onwards, the formation history of planetary systems.
IR spectroscopy in the range 12–230 μm with the SPace IR telescope for Cosmology and Astrophysics (SPICA) will reveal the physical processes governing the formation and evolution of galaxies and black holes through cosmic time, bridging the gap between the James Webb Space Telescope and the upcoming Extremely Large Telescopes at shorter wavelengths and the Atacama Large Millimeter Array at longer wavelengths. The SPICA, with its 2.5-m telescope actively cooled to below 8 K, will obtain the first spectroscopic determination, in the mid-IR rest-frame, of both the star-formation rate and black hole accretion rate histories of galaxies, reaching lookback times of 12 Gyr, for large statistically significant samples. Densities, temperatures, radiation fields, and gas-phase metallicities will be measured in dust-obscured galaxies and active galactic nuclei, sampling a large range in mass and luminosity, from faint local dwarf galaxies to luminous quasars in the distant Universe. Active galactic nuclei and starburst feedback and feeding mechanisms in distant galaxies will be uncovered through detailed measurements of molecular and atomic line profiles. The SPICA’s large-area deep spectrophotometric surveys will provide mid-IR spectra and continuum fluxes for unbiased samples of tens of thousands of galaxies, out to redshifts of z ~ 6.
A far-infrared observatory such as the SPace Infrared telescope for Cosmology and Astrophysics, with its unprecedented spectroscopic sensitivity, would unveil the role of feedback in galaxy evolution during the last ~10 Gyr of the Universe (z = 1.5–2), through the use of far- and mid-infrared molecular and ionic fine structure lines that trace outflowing and infalling gas. Outflowing gas is identified in the far-infrared through P-Cygni line shapes and absorption blueshifted wings in molecular lines with high dipolar moments, and through emission line wings of fine-structure lines of ionised gas. We quantify the detectability of galaxy-scale massive molecular and ionised outflows as a function of redshift in AGN-dominated, starburst-dominated, and main-sequence galaxies, explore the detectability of metal-rich inflows in the local Universe, and describe the most significant synergies with other current and future observatories that will measure feedback in galaxies via complementary tracers at other wavelengths.
A large outbreak of enterohaemorrhagic Escherichia coli (EHEC) O111 and O157 occurred in Japan in April 2011. We conducted an unmatched case-control study and trace-back investigation to determine the source of EHEC O111 infection and risk factors for severe complications. Pulsed-field gel electrophoresis was performed to help define cases. A total of 86 individuals met the case definition. Of these, 40% experienced haemolytic uraemic syndrome (HUS), 24% acute encephalopathy, and 6% died. Illness was significantly associated with eating the raw beef dish yukhoe (odds ratio 19·64, 95% confidence interval 7·03–54·83), the likely food vehicle. EHEC O111 and its closely related stx-negative variants were found in the beef. HUS occurred most frequently in individuals aged 5–9 years, and this age group was significantly associated with acute encephalopathy. The prevalence of HUS and acute encephalopathy was higher than in previous non-O157-related outbreaks, indicating a high risk of severe complications.
Eimeria tenella is recognized worldwide as a significant pathogen in the poultry industry. However, a lack of methods for isolating developing schizonts has hindered the use of transcriptome analyses to discover novel and developmentally regulated genes. In the present study, we characterized the long-term successive development of E. tenella in infected chicken caeca and assessed the utility of laser microdissection (LMD) for the isolation of schizont RNA. Developmental stages, including those of the first, second, and third-generation schizonts and gametocytes, were synchronous. Using LMD, only the mature second-generation schizonts were successfully excised from the lamina propria, and non-degraded RNA was purified from the schizonts. E. tenella-specific genes were amplified by reverse transcription polymerase chain reaction (RT-PCR). These results augment our understanding of the E. tenella life cycle, and reveal LMD as a potentially useful tool for gene expression analyses of the intracellular stages of E. tenella.
Metal abundances of the hot X-ray emitting interstellar medium (ISM) include important information to understand the history of star formation and evolution of galaxies. The metals are mainly synthesized by Type Ia (SNe Ia) and stellar mass loss in elliptical galaxies. The productions of stellar mass loss reflect stellar metallicity. SNe Ia mainly product Fe. Therefore, the abundance pattern of ISM can play key role to investigate the metal enrichment history.
We surveyed emm genotypes of group A streptococcus (GAS) isolates from patients with severe invasive streptococcal infections during 2001–2005 and compared their prevalence with that of the preceding 5 years. Genotype emm1 remained dominant throughout 2001 to 2005, but the frequency rate of this type decreased compared with the earlier period. Various other emm types have appeared in recent years indicating alterations in the prevalent strains causing severe invasive streptococcal infections. The cover of the new 26-valent GAS vaccine fell from 93·5% for genotypes of isolates from 1996–2000 to 81·8% in 2001–2005.
The number of patients with severe invasive group-G streptococcal (Streptococcus dysgalactiae subsp. equisimilis) infections has been increasing in Japan. The emm genotypes and SmaI-digested pulsed-field gel electrophoresis DNA profiles were variable among the strains isolated, suggesting there has not been clonal expansion of a specific subpopulation of strains. However, all strains carried scpA, ska, slo and sag genes, some of which may be involved in the pathogenesis of the disease.
We surveyed T serotypes and emm genotypes of Streptococcus pyogenes isolates from streptococcal toxic shock-like syndrome (TSLS) patients. T1 (emm1) remained dominant through 1992 to 2000, but the dominant T3 (emm3.1) strains from 1992 to 1995 disappeared during 1996–2000. Strains of several emm genotypes emerged during 1996–2000, indicating alterations in the prevalent strains causing TSLS.
We describe preliminary results from our study of multi-scale structures in Centaurus A (NGC 5128) obtained using the Chandra X-ray Observatory HRC-I observations. The high-angular resolution Chandra images reveal X-ray multi-scale structures in this object with unprecedented detail and clarity. The region surrounding the Cen A nucleus, believed to be associated with a supermassive black hole, shows structures on arcsecond scales clearly resolved from the central source.
There are three wide-field telescopes at the Bisei Spaceguard Center operated by the Japan Spaceguard Association. These telescopes are dedicated to detect near-earth asteroids and produce several tera-byte data per month. Since these data contain many main-belt asteroids, we will use them for an education program that will allow school pupils and the general public to find new main-belt asteroids. We are now developing a new software for its purpose.
An understanding of the biology of the cuticle in the larval stages of Ascariodea is of importance since the cuticle molecules not only possess a variety of functions related to survival but also have a potential role as a target for immunoprophylaxis. Thus, we made a preliminary characterization of surface proteins and antigens from 3rd-stage larvae (L3) and lung-stage larvae of Ascaris suum using two biotin-derivatives and two-dimensional polyacrylamide gel electrophoresis (2D–PAGE). The proteins labelled with biotin comprised a total of 37 and 32 spots, with molecular weights (Mr) ranging from 15 to 101kDa and isoelectric points (pI) from 3·8 to 7·6, in L3 and lung-stage larvae, respectively. The profiles revealed that the individual spots bound to one or both biotin derivatives. In addition, stage-common and stage-specific spots were found in L3 and lung-stage larvae. 2D–PAGE/immunoblotting analysis was performed with antisera from rabbits repeatedly inoculated with A. suum L3. Nineteen spots were recognized as surface antigens, with Mr ranging from 32 to 66kDa and pI from 4·9 to 7·6, from L3 and lung-stage larvae after alignment of the immunoblots with the profile of the surface proteins. These spots were found to include stage-common and stage-specific antigens. Identification of surface proteins by biotin labelling combined with 2D–PAGE allows a substantial shortening of sample preparation time for the target proteins, and will be a viable method for protein analysis of surface proteins and antigens of A. suum L3 and lung-stage larvae.
The chief activities of the Commission for this period were the organizing of two important meetings. The first was held as Joint Discussion 5 at the Kyoto General Assembly in August 1997. The proceedings have now appeared as “Preserving the Astronomical Windows”, edited by S. Isobe (1997).
A comprehensive study of transport properties and magnetism on β-MnO2 reveals the strong coupling between the conduction electrons and the localized spins which are supposed to form a magnetic helix below TN ∼ 92 K. We also show the direct evidences of the helical magnetism by means of the measurements of the anisotropy in the magnetic susceptibility and the observation of x ray magnetic scatterings on a single crystal of β-MnO2. These results are consistent with proper-type helix model proposed by Yoshimori [J. Phys. Soc. Jpn. 14, p. 807 (1959)]. This model also qualitatively agrees with the anisotropy in magnetoresistance that appears below TN. The pitch of the magnetic helix is not commensurate to the lattice and it is slightly temperature dependent. The intensity of several Bragg peaks drastically changes at TN suggesting that the magnetic ordering is accompanied by a lattice distortion.
ZnS nanocrystals doped with Mn2+ ions are prepared by a solution process and subsequent UV irradiation to produce the samples with different S/(Zn+Mn) ratios and/or surface modification by acrylic acids. Coordination states around Mn2+, ions were examined at 9 and 35 GHz by electron paramagnetic resonance spectroscopy. The Mn2+ sites in the vicinity of 2- vacancies or carboxyl groups are observed at the frequencies more than 9 or 35 GHz, respectively, for nanocrystals, but are not for the bulk sample of 250 nm diameter. Such Mn2+ sites enhance the photoluminescence due to d-d transition of Mn2+ ions through energy transfer from S2- vacancies or carboxyl groups, excited simultaneously by a light of 350 nm for exciting ZnS.
A sparingly soluble model drug, phenytoin (5,5-diphenyl-hydantoin, denoted as PT), was added during hydrolysis and polycondensation of tetra orthoethyl silicate (TEOS). The average size of the composite primary particles after in situ recrystallization of PT and gelation of silica was 2–3nm. The extent of hydrogen bond (HB) in PT was reduced after the complex formation (CF), while many PT molecules were attached by HB on the surface of silica gel. The apparent solubility to ethanol decreased to 29%∼18% by CF. The firstorder rate constant of dissolution of PT into H20 increased by CF up to 40 times. Addition of acrylamide also enhanced the dissolution rate. Mechanisms of faster dissolution were discussed in terms of the hydrogen bond reformation and microstructure.