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New composite based on polypyrrole (PPy) and bismuth oxide (α-Bi2O3) was investigated as supercapacitor electrode. The α-Bi2O3 was obtained by hydrothermal route at 500 ºC for 2 h. Cyclic voltammetry was used to electropolymerize PPy on graphite electrode (GE) or on GE/α-Bi2O3. The X-ray diffraction profile of Bi2O3 revealed the α-Bi2O3 monoclinic structure with space group P21/c.The scanning and transmission electron microscopy images showed that PPy coated α-Bi2O3. Raman spectra showed that PPy inhomogeneously coated α-Bi2O3, but it was still possible to obtain a α-Bi2O3 @PPy core-shell hybrid composite with highly ordered α-Bi2O3 with electronic interaction between the oxide and the polymer chain of the polymer. The GE/α-Bi2O3@PPy composite electrode (type I supercapacitor) displayed a predominantly capacitive profile with low impedance values and good electrochemical stability after 50 charge and discharge cycles. The specific capacitance of α-Bi2O3 @PPy composite was found in the range of 634 to 301 F g-1 to gravimetric current of 3 and 10 A g-1, respectively.

The quantum Hall effect is a macroscopic quantum phenomenon in a two-dimensional electron system. The two-dimensional electron system in SrTiO3 has sparked a great deal of interest, mainly because of the strong electron correlation effects expected from the 3d orbitals. Here we report the observation of the quantum Hall effect in a dilute La-doped SrTiO3-two-dimensional electron system, fabricated by metal organic molecular-beam epitaxy. The quantized Hall plateaus are found to be solely stemming from the low Landau levels with even integer-filling factors, ν=4 and 6 without any contribution from odd ν's. For ν=4, the corresponding plateau disappears on decreasing the carrier density. Such peculiar behaviours are proposed to be due to the crossing between the Landau levels originating from the two subbands composed of d orbitals with different effective masses. Our findings pave a way to explore unprecedented quantum phenomena in d-electron systems., Observation of quantum phenomena in correlated electron systems is challenging due to low mobility and high concentration of carriers. Here, Matsubara et al. report a two-dimensional electron system with high mobility-low carrier density in δ-doped SrTiO3, demonstrating quantum Hall effect in d-electron systems.

Simultaneous observations of microlensing events from multiple locations allow for the breaking of degeneracies between the physical properties of the lensing system, specifically by exploring different regions of the lens plane and by directly measuring the "microlens parallax". We report the discovery of a 30-55$M_J$ brown dwarf orbiting a K dwarf in microlensing event OGLE-2015-BLG-1319. The system is located at a distance of $\sim$5 kpc toward the Galactic bulge. The event was observed by several ground-based groups as well as by $Spitzer$ and $Swift$, allowing the measurement of the physical properties. However, the event is still subject to an 8-fold degeneracy, in particular the well-known close-wide degeneracy, and thus the projected separation between the two lens components is either $\sim$0.25 AU or $\sim$45 AU. This is the first microlensing event observed by $Swift$, with the UVOT camera. We study the region of microlensing parameter space to which $Swift$ is sensitive, finding that while for this event $Swift$ could not measure the microlens parallax with respect to ground-based observations, it can be important for other events. Specifically, for detecting nearby brown dwarfs and free-floating planets in high magnification events., 28 pages, 6 figures, 2 tables. Submitted to ApJ

We show a significant enhancement of specific capacity of a hybrid composite prepared with carbon nanotube (CNT), bone charcoal and Ag nanoparticle (NP) constituents which may be explained by a mechanism involving the electronic coupling of Fermi levels of the NP and defective CNT. This electronic coupling leads to an additional specific capacity which is given by (C NP xC CNT )/(C NP + C CNT ), where C NP and C CNT are the Li specific capacity of NP and CNT constituents, respectively. As a result, the specific capacity of defective carbon nanotube can be increased by twice with incorporation of only 0.8 wt.% of Ag NPs.

著者人数: 51名, Accepted: 2004-12-10, 資料番号: SA1003414000

著者人数: 51名, Accepted: 2004-03-24, 資料番号: SA1003408000

著者人数: 46名, Accepted: 2003-05-20, 資料番号: SA1003406000

The deflated surfaces of the alluvial fans in Saheki crater reveal the most detailed record of fan stratigraphy and evolution found, to date, on Mars. During deposition of at least the uppermost 100 m of fan deposits, discharges from the source basin consisted of channelized flows transporting sediment (which we infer to be primarily sand- and gravel-sized) as bedload coupled with extensive overbank mud-rich flows depositing planar beds of sand-sized or finer sediment. Flow events are inferred to have been of modest magnitude (probably less than ∼60 m3/s), of short duration, and probably occupied only a few distributaries during any individual flow event. Occasional channel avulsions resulted in the distribution of sediment across the entire fan. A comparison with fine-grained alluvial fans in Chile’s Atacama Desert provides insights into the processes responsible for constructing the Saheki crater fans: sediment is deposited by channelized flows (transporting sand through boulder-sized material) and overbank mudflows (sand size and finer) and wind erosion leaves channels expressed in inverted topographic relief. The most likely source of water was snowmelt released after annual or epochal accumulation of snow in the headwater source basin on the interior crater rim during the Hesperian to Amazonian periods. We infer the Saheki fans to have been constructed by many hundreds of separate flow events, and accumulation of the necessary snow and release of meltwater may have required favorable orbital configurations or transient global warming.

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We present the first example of binary microlensing for which the parameter measurements can be verified (or contradicted) by future Doppler observations. This test is made possible by a confluence of two relatively unusual circumstances. First, the binary lens is bright enough (I=15.6) to permit Doppler measurements. Second, we measure not only the usual 7 binary-lens parameters, but also the 'microlens parallax' (which yields the binary mass) and two components of the instantaneous orbital velocity. Thus we measure, effectively, 6 'Kepler+1' parameters (two instantaneous positions, two instantaneous velocities, the binary total mass, and the mass ratio). Since Doppler observations of the brighter binary component determine 5 Kepler parameters (period, velocity amplitude, eccentricity, phase, and position of periapsis), while the same spectroscopy yields the mass of the primary, the combined Doppler + microlensing observations would be overconstrained by 6 + (5 + 1) - (7 + 1) = 4 degrees of freedom. This makes possible an extremely strong test of the microlensing solution. We also introduce a uniform microlensing notation for single and binary lenses, we define conventions, summarize all known microlensing degeneracies and extend a set of parameters to describe full Keplerian motion of the binary lenses., Comment: 51 pages, 8 figures, 2 appendices. Submitted to ApJ. Fortran codes for Appendix B are attached to this astro-ph submission and are also available at http://www.astronomy.ohio-state.edu/~jskowron/OGLE-2009-BLG-020/

Analysis techniques in LHCf are presented, in which all techniques are required to have a high resolution and efficiency in order to overcome the severe situation, small lateral aperture and longitudinally short length of the detector. In this paper, methods for reconstructing an energy of electromagnetic shower are discussed following the data flow of measured data and Monte Carlo simulations.

The LHCf experiment is designed to measure energies and transverse momenta of neutral particles emitted in the forward region of s = 14 TeV p‐p collision at ±140 m away from the interaction point1 (IP1) of LHC. The energy resolution is confirm to be within 5% and the position resolution is better than 0.2 mm for gamma‐rays with energies from 100 GeV to 200 GeV by the test beam results at the CERN‐SPS. LHCf has taken data at 2009 and 2010 at s = 900 GeV and 7 TeV collision. A brief summary of LHCf operation at LHC is also reported here.

LHCf measures the energy and transverse momentum of neutral particles produced in the forward region of the LHC interaction point. In high energy cosmic ray measurements, the results strongly depend on the hadron interaction model which is used in the air shower simulation. LHCf will take data at s = 0.9, 2.4, 7, 10 and 14 TeV collisions at LHC and provide crucial calibration points for the hadron interaction models.

Carbonaceous materials with different structures are prepared by carbonization of sugarcane bagasse. Depending on carbonization conditions, it is possible to obtain soot rich in flakes or in honeycomb-shaped micrometric particles, whose concentration has large influence on lithium storage into electrodes. The soot rich in honeycomb-shaped particles provides the best electrochemical performance, with a reversible specific capacity of 310 mAh g-1. The results suggest that the sugarcane bagasse can be potentially used in the design of anodic materials for lithium ion batteries. Materiais carbonaceos com diferentes estruturas são preparados da carbonização do bagaço da cana de açúcar. Os materiais obtidos são caracterizados utilizando-se microscopia de varredura eletrônica e técnicas eletroquímicas. Dependendo das condições de carbonização é possível obter fuligens ricas de partículas tipo flocos ou tipo colméia de abelha, cuja concentração tem grande influência sobre a armazenagem de lítio nos eletrodos. Para fuligens ricas de partículas do tipo colméia observa-se uma capacidade específica reversível da ordem de 310 mAh g-1. Os resultados sugerem que o bagaço da cana pode ser um percursor com potencial para o desenvolvimento de materiais anódicos para baterias de ions de lítio.

We analyze the extreme high-magnification microlensing event OGLE-2008-BLG-279, which peaked at a maximum magnification of A ~ 1600 on 30 May 2008. The peak of this event exhibits both finite-source effects and terrestrial parallax, from which we determine the mass of the lens, M_l=0.64 +/- 0.10 M_Sun, and its distance, D_l = 4.0 +/- 0.6. We rule out Jupiter-mass planetary companions to the lens star for projected separations in the range 0.5-20 AU. More generally, we find that this event was sensitive to planets with masses as small as 0.2 M_Earth ~= 2 M_Mars with projected separations near the Einstein ring (~3 AU)., Comment: 25 pages, 7 figures, submitted to ApJ

To improve the planet detection efficiency, current planetary microlensing experiments are focused on high-magnification events searching for planetary signals near the peak of lensing light curves. However, it is known that central perturbations can also be produced by binary companions and thus it is important to distinguish planetary signals from those induced by binary companions. In this paper, we analyze the light curves of microlensing events OGLE-2007-BLG-137/MOA-2007-BLG-091, OGLE-2007-BLG-355/MOA-2007-BLG-278, and MOA-2007-BLG-199/OGLE-2007-BLG-419, for all of which exhibit short-term perturbations near the peaks of the light curves. From detailed modeling of the light curves, we find that the perturbations of the events are caused by binary companions rather than planets. From close examination of the light curves combined with the underlying physical geometry of the lens system obtained from modeling, we find that the short time-scale caustic-crossing feature occurring at a low or a moderate base magnification with an additional secondary perturbation is a typical feature of binary-lens events and thus can be used for the discrimination between the binary and planetary interpretations., 17 pages, 4 figures, 1 table

Kepler's supernova, discovered in October 1604, produced a remnant that has been well studied observationally in the radio, infrared, optical, and X-ray bands, and theoretically. Some models have predicted a TeV gamma-ray flux that is detectable with current Imaging Cherenkov Atmospheric Telescopes. We report on observations carried out in 2005 April with the CANGAROO-III telescope. No statistically significant excess was observed, and limitations on the allowed parameter range in the model are discussed., 6 pages 6 figures, to appear in ApJ, August 20, 2008, v683n2

We have observed the giant radio galaxy Centaurus A and the globular cluster $\omega$ Centauri in the TeV energy region using the CANGAROO-III stereoscopic system. The system has been in operation since 2004 withan array of four Imaging Atmospheric Cherenkov Telescopes (IACT) with $\sim$100-m spacings. The observations were carried out in March and April 2004. In total, approximately 10 hours data were obtained for each target.No statistically significant gamma-ray signal has been found above 420 GeV over a wide angular region (a one-degree radius from thepointing center) and we derive flux upper limits using all of the field of view.Implications for the total energy of cosmic rays and the density of the cold dark matter are considered., Comment: 7 pages, 6 figures, to appear in ApJ, emulateapj.cls

Sub-TeV gamma-ray emission from the North-West rim of the supernova remnant RX J0852.0$-$4622 was detected with the CANGAROO-II telescope and recently confirmed by the H.E.S.S. group. In addition, the H.E.S.S. data revealed a very wide (up to two degrees in diameter), shell-like profile of the gamma-ray emission. We have carried out CANGAROO-III observations in January and February 2005 with three telescopes and show here the results of three-fold coincidence data. We confirm the H.E.S.S. results about the morphology and the energy spectrum, and find the energy spectrum in the NW-rim is consistent with that of the whole remnant., 9 pages, 13 figures, to appear in ApJ

We made stereoscopic observations of the Vela Pulsar region with two of the 10 m diameter CANGAROO-III imaging atmospheric Cherenkov telescopes in January and February, 2004, in a search for sub-TeV gamma-rays from the pulsar and surrounding regions. We describe the observations, provide a detailed account of the calibration methods, and introduce the improved and bias-free analysis techniques employed for CANGAROO-III data. No evidence of gamma-ray emission is found from either the pulsar position or the previously reported position offset by 0.13 degree, and the resulting upper limits are a factor of five less than the previously reported flux from observations with the CANGAROO-I 3.8 m telescope. Following the recent report by the H.E.S.S. group of TeV gamma-ray emission from the Pulsar Wind Nebula, which is $\sim$0.5 degree south of the pulsar position, we examined this region and found supporting evidence for emission extended over $\sim$0.6 degree., 13 pages, 26 figures, emulateapj.cls, to appear in ApJ

著者人数: 46名, Accepted: 2004-02-16, 資料番号: SA1003381000

The concentrations of telithromycin, a new ketolide antimicrobial agent, in alveolar macrophages (AMs) and bronchoalveolar epithelial lining fluid (ELF) were determined in order to investigate the transfer of the drug into target tissue, relative to plasma, following multiple oral doses of telithromycin. Twenty-four healthy male Japanese volunteers were randomly allocated to four groups. Each subject was given 600 or 800 mg of telithromycin once daily for 5 days, followed by bronchoalveolar lavage (BAL) 2 or 8 h after the last dose (group A and B: 600 mg, 2 and 8 h BAL time point; group C and D: 800 mg, 2 and 8 h BAL time point). The mean concentrations of the drug in AMs and ELF were 34.54 and 4.92 mg/liter in group A, 50.97 and 2.26 mg/liter in group B, 25.47 and 4.24 mg/liter in group C, and 108.22 and 4.31 mg/liter in group D, respectively, which markedly exceeded concentrations in plasma. These results demonstrated good transfer of telithromycin into AMs and ELF, suggesting good efficacy against common respiratory pathogens, including intracellular pathogens and atypical microorganisms.

A search for extra-solar planets was carried out in three gravitational microlensing events of high magnification, MACHO 98-BLG-35, MACHO 99-LMC-2, and OGLE 00-BUL-12. Photometry was derived from observational images by the MOA and OGLE groups using an image subtraction technique. For MACHO 98-BLG-35, additional photometry derived from the MPS and PLANET groups was included. Planetary modeling of the three events was carried out in a super-cluster computing environment. The estimated probability for explaining the data on MACHO 98-BLG-35 without a planet is, 14 pages, 16 embedded postscript figures, 3 PNG figures, revised version accepted by MNRAS

We have recently reported that long-term administration of erythromycin at a low dose reduced the number of neutrophils and concentrations of interleukin 8 (IL-8) in bronchoalveolar lavage fluid in patients with chronic lower respiratory tract disease. To investigate the mechanism of action of erythromycin, we evaluated its effect on IL-8 production in the 1 alpha,25-dihydroxyvitamin D3-stimulated human monocytic cell line THP-1. Erythromycin at a concentration of 10 micrograms/ml significantly reduced IL-8 production by THP-1 cells stimulated with lipopolysaccharide (10 ng/ml) and 1% normal human serum compared with the amount produced by untreated cells (untreated cells, 2,448 pg/ml; erythromycin-treated cells, 872 pg/ml). Our results suggest that erythromycin may impair IL-8 production by alveolar macrophages, ultimately reducing neutrophil accumulation in the airspace.

We have studied the lateral distribution of charged particles associated with giant air showers and the attenuation of the local particle density at 600 m from the core, S600, with atmospheric depth using data collected with the Akeno Giant Air Shower Array (AGASA). The lateral distribution at distances of more than 1 km from the core has been observed to be much steeper than that suggested by some of the earlier measurements. The shape of the lateral distribution function has been observed to depend on the zenith angle of showers but there is no significant evidence for the dependence on the primary energy, within the resolution of the array. The systematic errors in energy estimation due to the uncertainties in the lateral distribution and the attenuation length of S600 are smaller than statistical errors. These errors have been estimated to be approximately 5% and approximately 3% respectively for near vertical showers with sec theta =1.1, and approximately 10% and approximately 12% respectively for showers with sec theta =1.4.

T. Tanimori, T. Tsukagoshi, T. Kifune, P. G. Edwards, M. Fujimoto, T. Hara, N. Hayashida, Y. Matsubara, Y. Mizumoto, Y. Muraki, S. Ogio, J. R. Patterson, M. D. Roberts, G. Rowell, T. Suda, T. Tamura, M. Teshima, G. J. Thornton, Y. Watase and T. Yoshikoshi

Isovaleric acidemia (IVA) is caused by a genetic deficiency of isovaleryl-CoA dehydrogenase (IVD). At least five distinct variant IVD alleles are known. We isolated five overlapping IVD cDNA clones from a human placenta cDNA library. They covered the entire coding region, except the initiation codon, and 587 bp in the 3'-noncoding region plus the poly(A) tail. The structure of the initiation site was identified by the study of genomic DNA and by the sequence comparison with rat IVD. Human IVD shared 89.6, 35.8, and 31.6% identical amino acid residues with rat IVD and human short and medium chain acyl-CoA dehydrogenases, respectively. In the Northern blot analysis of normal human liver and fibroblast poly(A)+ RNA, three mRNA species of different sizes (4.6, 3.8, and 2.1 kb) hybridized to IVD cDNA. Three mRNA species with similar sizes were also detected in five IVA fibroblast lines of different genotypes (variants 1, 1 X 2, 2, 3, and 5), suggesting that these variants are each due to a point mutation or small deletion.