311 research outputs found
Soybean protein fraction digested with neutral protease preparation, "Peptidase R", produced by Rhizopus oryzae, stimulates innate cellular immune system in mouse
ArticleInternational Immunopharmacology. 9(7-8):931-936 (2009)journal articl
Candidal adherence to cultured human cells of varying origin
published_or_final_versio
CO(J = 1-0) Imaging of M51 with CARMA and the Nobeyama 45 m Telescope
We report the CO(J = 1-0) observations of the Whirlpool Galaxy M51 using both the Combined Array for Research in Millimeter Astronomy (CARMA) and the Nobeyama 45 m telescope (NRO45). We describe a procedure for the combination of interferometer and single-dish data. In particular, we discuss (1) the joint imaging and deconvolution of heterogeneous data, (2) the weighting scheme based on the root-mean-square (rms) noise in the maps, (3) the sensitivity and uv coverage requirements, and (4) the flux recovery of a combined map. We generate visibilities from the single-dish map and calculate the noise of each visibility based on the rms noise. Our weighting scheme, though it is applied to discrete visibilities in this paper, should be applicable to grids in uv space, and this scheme may advance in future software development. For a realistic amount of observing time, the sensitivities of the NRO45 and CARMA visibility data sets are best matched by using the single-dish baselines only up to 4-6 kλ (about 1/4-1/3 of the dish diameter). The synthesized beam size is determined to conserve the flux between the synthesized beam and convolution beam. The superior uv coverage provided by the combination of CARMA long baseline data with 15 antennas and NRO45 short spacing data results in the high image fidelity, which is evidenced by the excellent overlap between even the faint CO emission and dust lanes in an optical Hubble Space Telescope image and polycyclicaromatichydrocarbon emission in a Spitzer 8 μm image. The total molecular gas masses of NGC 5194 and 5195 (d = 8.2 Mpc) are 4.9 × 10^9 M_⊙ and 7.8 × 10^7 M_⊙, respectively, assuming the CO-to-H_2 conversion factor of X _(CO) = 1.8 × 10^(20) cm-2(K km s^(–1))^(–1). The presented images are an indication of the millimeter-wave images that will become standard in the next decade with CARMA and NRO45, and the Atacama Large Millimeter/Submillimeter Array
Dynamical Simulations of NGC 2523 and NGC 4245
We present dynamical simulations of NGC 2523 and NGC 4245, two barred
galaxies (types SB(r)b and SB(r)0/a, respectively) with prominent inner rings.
Our goal is to estimate the bar pattern speeds in these galaxies by matching a
sticky-particle simulation to the -band morphology, using near-infrared
-band images to define the gravitational potentials. We compare the
pattern speeds derived by this method with those derived in our previous paper
using the well-known Tremaine-Weinberg continuity equation method. The inner
rings in these galaxies, which are likely to be resonance features, help to
constrain the dynamical models. We find that both methods give the same pattern
speeds within the errors.Comment: 29 pages, 3 tables, 13 figures. Accepted for publication in The
Astronomical Journa
Pattern speed of main spiral arms in NGC 2997: Estimate based on very young stellar complexes
Deep JHK-Brg photometry of the southern arm of the grand-design spiral galaxy
NGC 2997 was obtained by ISAAC/VLT. All sources in the field brighter than K=19
mag were located. Color-color diagrams were used to identify young stellar
complexes among the extended sources. Ages can be estimated for the youngest
complexes and correlated with azimuthal distances from the spiral arms defined
by the K-band intensity variation. The extended sources with Mk <-12 mag
display a diffuse appearance and are more concentrated inside the arm region
than fainter ones, which are compact and uniformly distributed in the disk. The
NIR colors of the bright diffuse objects are consistent with them being young
starforming complexes with ages <10 Myr and reddened by up to 8 mag of visual
extinction. They show a color gradient as a function of their azimuthal
distance from the spiral arms. Interpreting this gradient as an age variation,
the pattern speed Op = 16 km/s/kpc of the main spiral was derived assuming
circular motion. The alignment and color gradient of the bright, diffuse
complexes strongly support a density wave scenario for NGC 2997. Only the
brightest complexes with Mk <-12 mag show a well aligned structure along the
arm, suggesting that a strong compression in the gas due to the spiral
potential is required to form these most massive aggregates, while smaller
starforming regions are formed more randomly in the disk. The sharp transition
between the two groups at Mk = -12 mag may be associated with expulsion of gas
when the first supernovae explode in the complex.Comment: 4 pages, 5 figures. Accepted for publication as A&A Lette
Characterization and Improvement of the Image Quality of the Data Taken with the Infrared Camera (IRC) Mid-Infrared Channels onboard AKARI
Mid-infrared images frequently suffer artifacts and extended point spread
functions (PSFs). We investigate the characteristics of the artifacts and the
PSFs in images obtained with the Infrared Camera (IRC) onboard AKARI at four
mid-infrared bands of the S7 (7{\mu}m), S11 (11{\mu}m), L15 (15{\mu}m), and L24
(24 {\mu}m). Removal of the artifacts significantly improves the reliability of
the ref- erence data for flat-fielding at the L15 and L24 bands. A set of
models of the IRC PSFs is also constructed from on-orbit data. These PSFs have
extended components that come from diffraction and scattering within the
detector arrays. We estimate the aperture correction factors for point sources
and the surface brightness correction factors for diffuse sources. We conclude
that the surface brightness correction factors range from 0.95 to 0.8, taking
account of the extended component of the PSFs. To correct for the extended PSF
effects for the study of faint structures, we also develop an image
reconstruction method, which consists of the deconvolution with the PSF and the
convolution with an appropriate Gaussian. The appropriate removal of the
artifacts, improved flat-fielding, and image reconstruction with the extended
PSFs enable us to investigate de- tailed structures of extended sources in IRC
mid-infrared images.Comment: 35 pages, 15 figures, accepted for publication in PAS
The Kinematically Measured Pattern Speeds of NGC 2523 and NGC 4245
We have applied the Tremaine-Weinberg continuity equation method to derive
the bar pattern speed in the SB(r)b galaxy NGC 2523 and the SB(r)0/a galaxy NGC
4245 using the Calcium Triplet absorption lines. These galaxies were selected
because they have strong inner rings which can be used as independent tracers
of the pattern speed. The pattern speed of NGC 2523 is 26.4 6.1 km
s kpc, assuming an inclination of 49.7 and a distance
of 51.0 Mpc. The pattern speed of NGC 4245 is 75.5 31.3 km s
kpc, assuming an inclination of 35.4 and a distance of 12.6
Mpc. The ratio of the corotation radius to the bar radius of NGC 2523 and NGC
4245 is 1.4 0.3 and 1.1 0.5, respectively. These values place the
bright inner rings near and slightly inside the corotation radius, as predicted
by barred galaxy theory. Within the uncertainties, both galaxies are found to
have fast bars that likely indicate dark halos of low central concentration.
The photometric properties, bar strengths, and disk stabilities of both
galaxies are also discussed.Comment: Accepted for publication in The Astronomical Journal, 11 figures, 2
table
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