968 research outputs found
A New Test for the Absorption Mechanism of GPS Radio Sources Using Polarization Properties
We consider the use of polarization properties as a means to discriminate
between Synchrotron Self-Absorption (SSA) and Free--Free Absorption (FFA) in
GHz-Peaked Spectrum (GPS) sources. The polarization position angle (PA) of
synchrotron radiation at high frequencies for the optically thin regime is
perpendicular to the magnetic field, whereas it is parallel to the magnetic
field at low frequencies for the optically thick regime. Therefore, SSA
produces a change in PA of across the spectral peak, while FFA
does not result in such a change. We analyzed polarization data from VLA
observations for six GPS sources to see if such a change in PA was present. Our
results indicate that there is no significant evidence for change
in PA across the spectral peak, suggesting that FFA is more likely than SSA for
low-frequency cutoffs in these sources
Distribution of Faraday Rotation Measure in Jets from Active Galactic Nuclei II. Prediction from our Sweeping Magnetic Twist Model for the Wiggled Parts of AGN Jets and Tails
Distributions of Faraday rotation measure (FRM) and the projected magnetic
field derived by a 3-dimensional simulation of MHD jets are investigated based
on our "sweeping magnetic twist model". FRM and Stokes parameters were
calculated to be compared with radio observations of large scale wiggled AGN
jets on kpc scales. We propose that the FRM distribution can be used to discuss
the 3-dimensional structure of magnetic field around jets and the validity of
existing theoretical models, together with the projected magnetic field derived
from Stokes parameters. In the previous paper, we investigated the basic
straight part of AGN jets by using the result of a 2-dimensional axisymmetric
simulation. The derived FRM distribution has a general tendency to have a
gradient across the jet axis, which is due to the toroidal component of the
magnetic field generated by the rotation of the accretion disk. In this paper,
we consider the wiggled structure of the AGN jets by using the result of a
3-dimensional simulation. Our numerical results show that the distributions of
FRM and the projected magnetic field have a clear correlation with the large
scale structure of the jet itself, namely, 3-dimensional helix. Distributions,
seeing the jet from a certain direction, show a good matching with those in a
part of 3C449 jet. This suggests that the jet has a helical structure and that
the magnetic field (especially the toroidal component) plays an important role
in the dynamics of the wiggle formation because it is due to a current-driven
helical kink instability in our model.Comment: Accepted for publication in Ap
Active nematic liquid crystals under a quenched random field
Coupling between flow and orientation is a central issue in understanding the
collective dynamics of active biofilaments and cells. Active stressess
generated by motor activity destroy (quasi-)long-range orientational order and
induce chaotic vortex flows. In cellular and subcellular environment, alignment
is also hindered by heterogeneous filamentous structures in extracellular
matrix and various organelles in a cell. Here we address the effects of a
quenched random field on the flow patterns and orientational order in
two-dimensional active nematic liquid crystals. We found that the director
dynamics is frozen above a critical disorder strength. For sufficiently strong
randomness, the orientational correlation function decays exponentially with
the distance, reproducing the behavior of passive random-field nematics. In
contrast, the flow velocity decreases only gradually as the randomness is
increased, and develops a logarithmic spatial correlation for strong disorder.
The threshold between the activity- and disorder-dominated regimes is specified
and its dependence on the activity parameter is discussed.Comment: 6 pages, 4 figure
For Vol.70, No.5 pp405-408 A Multicenter, Prospective, Randomized Controlled Trial Evaluating the Efficacy of Rectal Diclofenac and Sublingual Nitrate as a Combined Prophylactic Treatment for Post-ERCP Pancreatitis
In the article by Tomoda T et al. entitled “A Multicenter, Prospective, Randomized Controlled Trial Evaluating the Efficacy of Rectal Diclofenac and Sublingual Nitroglycerin as a Combined Prophylactic Treatment for Post-ERCP Pancreatitis”, which appeared in the October 2016 issue, Vol. 70, No. 5, pp405-408, the word “nitroglycerin” should be corrected to “nitrate” throughout the manuscript
Hyper-luminous Dust Obscured Galaxies discovered by the Hyper Suprime-Cam on Subaru and WISE
We present the photometric properties of a sample of infrared (IR) bright
dust obscured galaxies (DOGs). Combining wide and deep optical images obtained
with the Hyper Suprime-Cam (HSC) on the Subaru Telescope and all-sky mid-IR
(MIR) images taken with Wide-Field Infrared Survey Explorer (WISE), we
discovered 48 DOGs with and , where
, , and [22] represent AB magnitude in the -band,
-band, and 22 m, respectively, in the GAMA 14hr field
( 9 deg). Among these objects, 31 ( 65 %) show power-law
spectral energy distributions (SEDs) in the near-IR (NIR) and MIR regime, while
the remainder show a NIR bump in their SEDs. Assuming that the redshift
distribution for our DOGs sample is Gaussian, with mean and sigma = 1.99
0.45, we calculated their total IR luminosity using an empirical relation
between 22 m luminosity and total IR luminosity. The average value of the
total IR luminosity is (3.5 1.1) L, which
classifies them as hyper-luminous infrared galaxies (HyLIRGs). We also derived
the total IR luminosity function (LF) and IR luminosity density (LD) for a
flux-limited subsample of 18 DOGs with 22 m flux greater than 3.0 mJy and
with -band magnitude brighter than 24 AB magnitude. The derived space
density for this subsample is log = -6.59 0.11 [Mpc]. The
IR LF for DOGs including data obtained from the literature is well fitted by a
double-power law. The derived lower limit for the IR LD for our sample is
3.8 10 [L Mpc] and
its contributions to the total IR LD, IR LD of all ultra-luminous infrared
galaxies (ULIRGs), and that of all DOGs are 3 %, 9 %, and 15 %,
respectively.Comment: 15 pages, 15 figures, and 3 tables, accepted for publication in PASJ
(Subaru special issue
A brainstem anosognosia of hemiparesis
A woman had anosognosia for hemiplegia as a manifestation of brainstem infarction. She had no mental or neuropsychological disturbances, and had involvement of the brainstem in the frontal/parietal-subcortical circuits to the right cerebral hemisphere. Brainstem lesions that disrupt frontal/parietal-subcortical areas may affect anosognosia for hemiplegia
Camptocormia in Parkinson's Disease
Objectives. Abnormalities of posture represent one of the main features of Parkinson's disease (PD). Among them, camptocormia has been considered as rare in PD. We investigated frequency and clinical features of camptocormia in PD patients. Methods. 153 PD patients (mean 68.5 ± 10.7 years old, duration 5.9 ± 2.4 years) outpatiently recruited. After neurologic examination, patients were rated on the Unified PD Rating Scale motor scale (UPDRS Part III), minimental state examination (MMSE). Also we evaluated patients with camptocormia by MRI. Of the 153 PD patients, 27 had camptocormia (mean age, 67.9 ± 7.9 years old; disease duration, 6.1 ± 3.9 years). For further evaluation, we recruited age- and sex-matched 27 PD patients without camptocormia (11 men and 16 women; mean age ± SD, 69.2 ± 10.1 years, duration 6.0 ± 2.7 years) These selected 54 patients completed several self-assessments. Lumbar and thoracic paraspinal muscles were studied by EMG. Results. There were no significant differences in age, duration, severity, and drug dose between patients with and without camptocormia. Analysis of NMSS subitems indicated that PD patients tended to show lower scores for sleep/fatigue, attention/memory, and miscellaneous items. Conclusions. We found significant differences concerning nonmotor signs and symptoms evaluated by FAB, PDQ-8, FSQ, VAS-F, and NMSS between patients with and without camptocormia. Our findings indicate that camptocormia is a relatively common sign in PD and that patients with camptocormia scores on the PDQ-8 compared with PD patients without camptocormia. This suggests that improvements in camptocormia of PD patients may improve their QOL
AN EPIDEMIOLOGICAL OBSERVATION OF JAPANESE B ENCEPHALITIS PREVAILED OVER OKAYAMA PREFECTURE DURING THE PAST 8 YEAR FROM 1946 TILL 1953
From the epidemiological point of view, an observation was made on the features of Japanese B encephalitis, which occurred and prevailed in Okayama Prefecture, where the outbreak of this disease has been reported all these 8 years from 1946 till 1953. Almost every year, the number of patients in this prefecture exceeded the average one of the whole country. In addition, it seemed to indicate serious outbreak with the period of
about 10 years. Every outbreak has taken place between mid-August and early September. Both children and aged people were susceptible to this disease, the mortality being low in children and somewhat high in the aged patients. Male patients were more numerous than female patients. It is interesting to note that, when the local origin of the patients was investigated, it appeared that many children patients were of the southern parts of the prefecture and many aged patients of the northern parts, where the mortality caused by the disease is somewhat higher. Further investigation in this respect will be done in the future. The peak of this disease was usually seen to be reached in the south about two weeks earlier than in the north. Thus it may well be said that the features of the prevalence of this disease have an intimate relation with the climatic condition. The differential diagnosis of this disease was found to be difficult when accompanied with tuberculolus meningitis, ekiri, dysentery and some other disease with encephalitic or meningitic symptom
First Data Release of the Hyper Suprime-Cam Subaru Strategic Program
The Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) is a three-layered
imaging survey aimed at addressing some of the most outstanding questions in
astronomy today, including the nature of dark matter and dark energy. The
survey has been awarded 300 nights of observing time at the Subaru Telescope
and it started in March 2014. This paper presents the first public data release
of HSC-SSP. This release includes data taken in the first 1.7 years of
observations (61.5 nights) and each of the Wide, Deep, and UltraDeep layers
covers about 108, 26, and 4 square degrees down to depths of i~26.4, ~26.5, and
~27.0 mag, respectively (5sigma for point sources). All the layers are observed
in five broad bands (grizy), and the Deep and UltraDeep layers are observed in
narrow bands as well. We achieve an impressive image quality of 0.6 arcsec in
the i-band in the Wide layer. We show that we achieve 1-2 per cent PSF
photometry (rms) both internally and externally (against Pan-STARRS1), and ~10
mas and 40 mas internal and external astrometric accuracy, respectively. Both
the calibrated images and catalogs are made available to the community through
dedicated user interfaces and database servers. In addition to the pipeline
products, we also provide value-added products such as photometric redshifts
and a collection of public spectroscopic redshifts. Detailed descriptions of
all the data can be found online. The data release website is
https://hsc-release.mtk.nao.ac.jp/.Comment: 34 pages, 20 figures, 7 tables, moderate revision, accepted for
publication in PAS
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