138 research outputs found
Astrometry of HO Masers in Nearby Star-Forming Regions with VERA --- IV. L1448C
We have carried out multi-epoch VLBI observations with VERA (VLBI Exploration
of Radio Astrometry) of the 22~GHz HO masers associated with a Class 0
protostar L1448C in the Perseus molecular cloud. The maser features trace the
base of collimated bipolar jet driven by one of the infrared counter parts of
L1448C named as L1448C(N) or L1448-mm A. We detected possible evidences for
apparent acceleration and precession of the jet according to the
three-dimensional velocity structure. Based on the phase-referencing VLBI
astrometry, we have successfully detected an annual parallax of the HO
maser in L1448C to be 4.310.33~milliarcseconds (mas) which corresponds to
a distance of 23218~pc from the Sun. The present result is in good
agreement with that of another HO maser source NGC~1333 SVS13A in the
Perseus molecular cloud, 235~pc. It is also consistent with the photometric
distance, 220~pc. Thus, the distance to the western part of the Perseus
molecular cloud complex would be constrained to be about 235~pc rather than the
larger value, 300~pc, previously reported.Comment: 15 pages, 5 figures, accepted for publication in PAS
Initial distribution volume of glucose can be approximated using a conventional glucose analyzer in the intensive care unit
INTRODUCTION: We previously reported that initial distribution volume of glucose (IDVG) reflects central extracellular fluid volume, and that IDVG may represent an indirect measure of cardiac preload that is independent of the plasma glucose values present before glucose injection or infusion of insulin and/or vasoactive drugs. The original IDVG measurement requires an accurate glucose analyzer and repeated arterial blood sampling over a period of 7 min after glucose injection. The purpose of the present study was to compare approximated IDVG, derived from just two blood samples, versus original IDVG, and to test whether approximated IDVG is an acceptable alternative measure of IDVG in the intensive care unit. METHODS: A total of 50 consecutive intensive care unit patients were included, and the first IDVG determination in each patient was analyzed. Glucose (5 g) was injected through the central venous line to calculate IDVG. Original IDVG was calculated using a one-compartment model from serial incremental arterial plasma glucose concentrations above preinjection using a reference glucose analyzer. Approximated IDVG was calculated from glucose concentrations in both plasma and whole blood, using a combined blood gas and glucose analyzer, drawn at two time points: immediately before glucose injection and 3 min after injection. Subsequently, each approximated IDVG was calculated using a formula we proposed previously. RESULTS: The difference (mean ± standard deviation) between approximated IDVG calculated from plasma samples and original IDVG was -0.05 ± 0.54 l, and the difference between approximated IDVG calculated from whole blood samples and original IDVG was -0.04 ± 0.61 l. There was a linear correlation between approximated and original IDVG (r(2 )= 0.92 for plasma samples, and r(2 )= 0.89 for whole blood samples). CONCLUSION: Our findings demonstrate that there was good correlation between each approximated IDVG and original IDVG, although the two measures are not interchangeable. This suggests that approximated IDVG is clinically acceptable as an alternative calculation of IDVG, although approximated and original IDVGs are not equivalent; plasma rather than whole blood measurements are preferable
Report on the method for determining the location of the polar vortex boundary region
To determine the boundary region of the polar vortex objectively using the PV distribution on isentropic surfaces, the equivalent latitude(Eql) of the polar vortex boundary was calculated using a slightly modified form of the technique of E.R. Nash et al.(J. Geophys. Res., 101D, 9471, 1996). Using the NCEP/NCAR reanal- ysis data, the Eql of the polar vortex boundary region in the winter of 1999/2000 was calculated, and compared with the ozone mixing ratio in the lower stratosphere over Eureka observatory(80°N , 86°W ). The results indicate that this method determines the boundary region of the polar vortex well
Annual Parallax Measurements of an Infrared Dark Cloud MSXDC G034.43+00.24 with VERA
We have measured the annual parallax of the H2O maser source associated with
an infrared dark cloud MSXDC G034.43+00.24 from the observations with VERA
(VLBI Exploration of Radio Astrometry). The parallax is 0.643 +/- 0.049 mas,
corresponding to the distance of 1.56 +0.12/-0.11 kpc. This value is less than
the half of the previous kinematic distance of 3.7 kpc. We revise the core mass
estimates of MSXDC G034.43+00.24, based on virial masses, LTE masses and dust
masses and show that the core masses decrease from the previous estimations of
~1000 Mo to hundreds of Mo. The spectral type derived from the luminosity also
changes from O9.5 to B1 in the case of MM1. This spectral type is still
consistent with that of the massive star. The radial velocity derived from the
flat rotation model is smaller than the observed velocity, which corresponds to
the peculiar motion of ~40 km/s in the line-of-sight direction.Comment: 14 pages, 11 figures, accepted to PASJ (vol. 63, No. 3
Preoperative Butyrylcholinesterase Level as an Independent Predictor of Overall Survival in Clear Cell Renal Cell Carcinoma Patients Treated with Nephrectomy
The prognostic factors for the overall survival (OS) of clear cell renal cell carcinoma (ccRCC) patients treated with nephrectomy are not well defined. In the present study, we investigated the prognostic significance of preoperative butyrylcholinesterase (BChE) levels in 400 ccRCC patients undergoing radical or partial nephrectomy from 1992 to 2013 at our institution. Univariate and multivariate analyses were performed to determine the clinical factors associated with OS. Among the enrolled patients, 302 were diagnosed with organ-confined disease only (T1-2N0M0), 16 with lymph node metastases, and 56 with distant metastases. The median preoperative BChE level was 250 U/L (normal range, 168–470 U/L), and median follow-up period was 36 months. The 3-year OS rate in patients with preoperative BChE levels of ≥100 U/L was significantly higher than in those with levels of <100 U/L (89.3% versus 77.7%, P=0.004). On univariate analysis, performance status; anemia; hypoalbuminemia; preoperative levels of BChE, corrected calcium, and C-reactive protein; and distant metastasis status were significantly associated with OS. Multivariate analysis revealed that preoperative BChE levels and distant metastasis status were significantly associated with OS. Our findings suggest a possible role of preoperative BChE levels as an independent predictor of OS after nephrectomy in ccRCC patients
Astrometry of Water Maser Sources in Nearby Molecular Clouds with VERA - II. SVS 13 in NGC 1333
We report on the results of multi-epoch VLBI observations with VERA (VLBI
Exploration of Radio Astrometry) of the 22 GHz H2O masers associated with the
young stellar object SVS 13 in the NGC 1333 region. We have carried out
phase-referencing VLBI astrometry and measured an annual parallax of the maser
features in SVS 13 of 4.25+/-0.32 mas, corresponding to the distance of
235+/-18 pc from the Sun. Our result is consistent with a photometric distance
of 220 pc previously reported. Even though the maser features were detectable
only for 6 months, the present results provide the distance to NGC 1333 with
much higher accuracy than photometric methods. The absolute positions and
proper motions have been derived, revealing that the H2O masers with the LSR
(local standard of rest) velocities of 7-8 km s-1 are most likely associated
with VLA4A, which is a radio counterpart of SVS 13. The origin of the observed
proper motions of the maser features are currently difficult to attribute to
either the jet or the rotating circumstellar disk associated with VLA4A, which
should be investigated through future high-resolution astrometric observations
of VLA4A and other radio sources in NGC 1333.Comment: 9 pages, 5 figures. PASJ, in press (2008, Vol. 60, No. 1
Astrometry of Galactic Star Forming Region Sharpless 269 with VERA : Parallax Measurements and Constraint on Outer Rotation Curve
We have performed high-precision astrometry of H2O maser sources in Galactic
star forming region Sharpless 269 (S269) with VERA. We have successfully
detected a trigonometric parallax of 189+/-8 micro-arcsec, corresponding to the
source distance of 5.28 +0.24/-0.22 kpc. This is the smallest parallax ever
measured, and the first one detected beyond 5 kpc. The source distance as well
as proper motions are used to constrain the outer rotation curve of the Galaxy,
demonstrating that the difference of rotation velocities at the Sun and at S269
(which is 13.1 kpc away from the Galaxy's center) is less than 3%. This gives
the strongest constraint on the flatness of the outer rotation curve and
provides a direct confirmation on the existence of large amount of dark matter
in the Galaxy's outer disk.Comment: 7 pages and 4 figures, Accepted by PASJ (Vol. 59, No. 5, October 25,
2007 issue
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