815 research outputs found
FeII/MgII Emission Line Ratios of QSOs. II. z>6 Objects
Near-infrared spectra of four QSOs located at are obtained with the
OH-airglow suppressor mounted on the Subaru telescope. The FeII/MgII
emission-line ratios of these QSOs are examined by the same fitting algorithm
as in our previous study of QSOs. The fitting results show that two out
of the four QSOs have significant FeII emission in their rest-UV spectra,
while the other two have almost no FeII features. We also applied our fitting
algorithm to more than 10,000 SDSS QSOs and found two trends in the
distribution of FeII/MgII against redshift: (1) the upper envelope of the
FeII/MgII distribution at shows a probable declination toward high
redshift, and (2) the median distribution settles into lower ratios at with small scatter compared to the other redshift. We discuss an Fe/Mg
abundance evolution of QSOs with a substantial contribution from the diverse
nature of the broad-line regions in high-redshift QSOs.Comment: 12 pages, 2 figures. Accepted for publication in ApJ (10 October
2004, v614
Ground-state properties of the one-dimensional attractive Hubbard model with confinement: a comparative study
We revisit the one-dimensional attractive Hubbard model by using the
Bethe-ansatz based density-functional theory and density-matrix renormalization
method. The ground-state properties of this model are discussed in details for
different fillings and different confining conditions in weak-to-intermediate
coupling regime. We investigate the ground-state energy, energy gap, and
pair-binding energy and compare them with those calculated from the canonical
Bardeen-Cooper-Schrieffer approximation. We find that the Bethe-ansatz based
density-functional theory is computationally easy and yields an accurate
description of the ground-state properties for weak-to-intermediate interaction
strength, different fillings, and confinements. In order to characterize the
quantum phase transition in the presence of a harmonic confinement, we
calculate the thermodynamic stiffness, the density-functional fidelity, and
fidelity susceptibility, respectively. It is shown that with the increase of
the number of particles or attractive interaction strength, the system can be
driven from the Luther-Emery-type phase to the composite phase of
Luther-Emery-like in the wings and insulating-like in the center.Comment: 13 pages with 10 figures and 2 table
Expression of vesicular glutamate transporters in sensory and autonomic neurons innervating the mouse urinary bladder
Purpose: Vesicular glutamate transporters (VGLUTs), essential for loading glutamate into synaptic vesicles, are present in various neuronal systems. However, the expression of VGLUTs in neurons innervating the urinary bladder has not yet been analyzed. Here, we study the presence of VGLUTs type-1, -2 and -3 (VGLUT1, VGLUT2 and VGLUT3, respectively) in mouse urinary bladder neurons. Materials and Methods: Expression of VGLUT1, VGLUT2 and calcitonin gene-related peptide (CGRP) was analyzed by immunohistochemistry in retrogradely labeled primary afferent and autonomic neurons of BALB/C mice after injecting Fast Blue in the urinary bladder wall. To study VGLUT3, retrograde tracing of the urinary bladder was performed in transgenic mice where VGLUT3 is identified by detection of enhanced green fluorescent protein (EGFP). Results: Most urinary bladder DRG neurons expressed VGLUT2. A smaller percentage of neurons also expressed VGLUT1 or VGLUT3. Coexpression with CGRP was only observed for VGLUT2. Occasional VGLUT2-immunoreactive (IR) neurons were seen in the major pelvic ganglion (MPG). Abundant VGLUT2-IR nerves were detected in the urinary bladder dome, trigone and also the urethra; VGLUT1-IR nerves were discretely present. Conclusions: We present novel data on the expression of VGLUTs in sensory and autonomic neurons innervating the mouse urinary bladder. The frequent association of VGLUT2 and CGRP in sensory neurons suggests interactions between glutamatergic and peptidergic neurotransmissions, potentially influencing commonly perceived sensations in the urinary bladder, such as discomfort and pain.Fil: Brumovsky, Pablo Rodolfo. Universidad Austral. Facultad de Ciencias Biomédicas. Laboratorio de Investigaciones Biomédicas; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; Argentina. University of Pittsburgh. Department of Anesthesiology. Pittsburgh Center for Pain Research; Estados UnidosFil: Seal, Rebecca P.. University of Pittsburgh. Department of Anesthesiology. Pittsburgh Center for Pain Research; Estados UnidosFil: Lundgren, Kerstin H.. University of Cincinnati. Department of Neurology; Estados UnidosFil: Seroogy, Kim B.. University of Cincinnati. Department of Neurology; Estados UnidosFil: Watanabe, Masahiko. Hokkaido University School of Medicine. Department of Anatomy; JapónFil: Gebhart, G. F.. University of Pittsburgh. Department of Anesthesiology. Pittsburgh Center for Pain Research; Estados Unido
The Apparent Host Galaxy of PKS 1413+135: HST, ASCA and VLBA Observations
PKS 1413+135 (z=0.24671) is one of very few radio-loud AGN with an apparent
spiral host galaxy. Previous authors have attributed its nearly exponential
infrared cutoff to heavy absorption but have been unable to place tight limits
on the absorber or its location in the optical galaxy. In addition, doubts
remain about the relationship of the AGN to the optical galaxy given the
observed lack of re-emitted radiation. We present new HST, ASCA and VLBA
observations which throw significant new light on these issues. The HST
observations reveal an extrremely red color (V-H = 6.9 mag) for the active
nucleus of PKS 1413+135, requiring both a spectral turnover at a few microns
due to synchrotron aging and a GMC-sized absorber. We derive an intrinsic
column N_H = 4.6^{+2.1}_{-1.6} times 10^{22}cm^{-2} and covering fraction f =
0.12^{+0.07}_{-0.05}. As the GMC is likely in the disk of the optical galaxy,
our sightline is rather unlikely (P ~ 2 times 10^{-4}). The properties of the
GMC typical of GMCs in our own galaxy. The HI absorber appears centered 25
milliarcseconds away from the nucleus, while the X-ray and nearly all of the
molecular absorbers must cover the nucleus, implying a complicated geometry and
cloud structure, with a molecular core along our line of sight to the nucleus.
Interestingly, the HST/NICMOS data require the AGN to be decentered relative to
the optical galaxy by 13 +/- 4 milliarcseconds. This could be interpreted as
suggestive of an AGN location far in the background compared to the optical
galaxy, but it can also be explained by obscuration and/or nuclear structure,
which is more consistent with the observed lack of multiple images.Comment: 27 pages, 8 figures; accepted to A
Soundness of Unravelings for Conditional Term Rewriting Systems via Ultra-Properties Related to Linearity
Unravelings are transformations from a conditional term rewriting system
(CTRS, for short) over an original signature into an unconditional term
rewriting systems (TRS, for short) over an extended signature. They are not
sound w.r.t. reduction for every CTRS, while they are complete w.r.t.
reduction. Here, soundness w.r.t. reduction means that every reduction sequence
of the corresponding unraveled TRS, of which the initial and end terms are over
the original signature, can be simulated by the reduction of the original CTRS.
In this paper, we show that an optimized variant of Ohlebusch's unraveling for
a deterministic CTRS is sound w.r.t. reduction if the corresponding unraveled
TRS is left-linear or both right-linear and non-erasing. We also show that
soundness of the variant implies that of Ohlebusch's unraveling. Finally, we
show that soundness of Ohlebusch's unraveling is the weakest in soundness of
the other unravelings and a transformation, proposed by Serbanuta and Rosu, for
(normal) deterministic CTRSs, i.e., soundness of them respectively implies that
of Ohlebusch's unraveling.Comment: 49 pages, 1 table, publication in Special Issue: Selected papers of
the "22nd International Conference on Rewriting Techniques and Applications
(RTA'11)
Histidine-rich Glycoprotein Could Be an Early Predictor of Vasospasm after Aneurysmal Subarachnoid Hemorrhage
Cerebral vasospasm (CVS) is a major contributor to the high morbidity and mortality of aneurysmal subarachnoid hemorrhage (aSAH) patients. We measured histidine-rich glycoprotein (HRG), a new biomarker of aSAH, in cerebrospinal fluid (CSF) to investigate whether HRG might be an early predictor of CVS. A total of seven controls and 14 aSAH patients (8 males, 6 females aged 53.4±15.4 years) were enrolled, and serial CSF and serum samples were taken. We allocated these samples to three phases (T1-T3) and measured HRG, interleukin (IL)-6, fibrinopeptide A (FpA), and 8-hydroxy-2’-deoxyguanosine (8OHdG) in the CSF, and the HRG in serum. We also examined the release of HRG in rat blood incubated in artificial CSF. In contrast to the other biomarkers examined, the change in the CSF HRG concentration was significantly different between the nonspasm and spasm groups (p<0.01). The rat blood/CSF model revealed a time course similar to that of the human CSF samples in the non-spasm group. HRG thus appears to have the potential to become an early predictor of CVS. In addition, the interaction of HRG with IL-6, FpA, and 8OHdG may form the pathology of CVS
Topological Dislocations and Mixed State of Charge Density Waves
We discuss the possibility of the ``mixed state'' in incommensurate charge
density waves with three-dimensional order. It is shown that the mixed state
can be created by applying an electric field perpendicular to the chains. This
state consists of topological dislocations induced by the external field and is
therefore similar to the mixed states of superfluids (type-II superconductor or
liquid Helium II). However, the peculiar coupling of charge density waves with
the electric field strongly modifies the nature of the mixed state compared to
the conventional superfluids. The field and temperature dependence of the
properties of the mixed state are studied, and some experimental aspects are
discussed.Comment: 10 pages, Revtex format, no figures, to appear in Phys. Rev. Let
The Korean Financial System: Overcoming the Global Financial Crisis and Addressing Remaining Problems
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