290 research outputs found
H2O maser motions and the distance of the star forming region G192.16-3.84
We present the results of astrometic observations of H2O masers associated
with the star forming region G192.16-3.84 with the VLBI Exploration of Radio
Astrometry (VERA). The H2O masers seem to be associated with two young stellar
objects (YSOs) separated by \sim1200 AU as reported in previous observations.
In the present observations, we successfully detected an annual parallax of
0.66 \pm 0.04 mas for the H2 O masers, which corresponds to a distance to
G192.16-3.84 of D = 1.52 \pm 0.08 kpc from the Sun. The determined distance is
shorter than the estimated kinematic distance. Using the annual parallax
distance and the estimated parameters of the millimeter continuum emission, we
estimate the mass of the disk plus circumstellar cloud in the southern young
stellar object to be 10.0+4.3M\cdot. We also estimate the galactocentric
distance and the peculiar motion -3.6 of G192.16-3.84, relative to a circular
Galactic rotation: R\star = 9.99 \pm 0.08 kpc, Z\star = -0.10 \pm 0.01 kpc, and
(U\star,V\star,W\star)=(-2.8\pm1.0,-10.5\pm0.3,4.9\pm2.7)[kms-1]respectively.
The peculiar motion of G192.16-3.84 is within that typically found in recent
VLBI astrometric results. The angular distribution and three-dimensional
velocity field of H2O maser features associated with the northern YSO indicate
the existence of a bipolar outflow with a major axis along the
northeast-southwest direction.Comment: 9 pages, 2 figures and 4 tables. Accepted for publication on PAS
Specific binding of okadaic acid, a new tumor promoter in mouse skin
AbstractThe tumor promoter okadaic acid binds specifically to a particulate as well as a cytosolic fraction of various mouse tissues, e.g., skin, brain, lung and colon. The KD value was 21.7 nM for receptors in the particulate fraction and 1.0 nM for those in the cytosolic fraction of mouse skin. The specific binding of [3H]okadaic acid to the particulate fraction of mouse skin was inhibited dose-dependently by okadaic acid, but not okaidaic acid tetramethyl ether, an inactive compound, or by other tumor promoters, such as 12-O-tetradecanoylphorbol-13-acetate and teleocidin. The results suggest a new pathway of tumor promotion mediated through the okadaic acid receptor(s)
VLBI Monitoring of 3C 84 (NGC 1275) in Early Phase of the 2005 Outburst
Multi-epoch Very Long Baseline Interferometry (VLBI) study of the sub-pc
scale jet of 3C 84 is presented. We carried out 14-epoch VLBI observations
during 2006-2009 with the Japanese VLBI Network (JVN) and the VLBI Exploration
of Radio Astrometry (VERA), immediately following the radio outburst that began
in 2005. We confirmed that the outburst was associated with the central ~1 pc
core, accompanying the emergence of a new component. This is striking evidence
of the recurrence of jet activity. The new component became brighter during
2008, in contrast to the constant gamma-ray emission that was observed with the
Fermi Gamma-ray Space Telescope during the same time. We found that the
projected speed of the new component is 0.23c from 2007/297 (2007 October 24)
to 2009/114 (2009 April 24). The direction of movement of this component
differs from that of the pre-existing component by ~40 degree. This is the
first measurement of kinematics of a sub-pc jet in a gamma-ray active phase.
Possible detection of jet deceleration and the jet kinematics in connection
with the gamma-ray emission is discussed.Comment: 5 pages, 3 figures. Accepted for publication in PAS
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