846 research outputs found
Continued strength at Tenth District banks
Commercial banks in Tenth District states continued to perform well in the first half of 1994. Profitability leveled off at a high level, asset quality improved, and loan growth accelerated. Based on these performance measures, banks in district states once again outperformed banks in the rest of the nation.Bank profits ; Federal Reserve District, 10th
Gravitational Lensing Statistics in Universes Dominated by Dark Energy
We study lens statistics in flat, low-density universes with different
equations of state for the dark energy component. Dark energy
modifies the distance-redshift relation and the mass function of dark matter
halos leading to changes in the lensing optical depth as a function of image
separation. Those effects must, however, be distinguished from effects
associated with the structure of dark matter halos. Baryonic cooling causes
galaxy-mass halos to have different central density profiles than group- and
cluster-mass halos, which causes the distribution of normal arcsecond-scale
lenses to differ from the distribution of ``wide-separation'' (\Delta\theta
\gtrsim 4\arcsec) lenses. Fortunately, the various parameters related to
cosmology and halo structure have very different effects on the overall image
separation distribution: (1) the abundance of wide-separation lenses is
exremely sensitive (by orders of magnitude) to the distribution of
``concentration'' parameters for massive halos modeled with the
Navarro-Frenk-White profile; (2) the transition between normal and
wide-separation lenses depends mainly on the mass scale where baryonic cooling
ceases to be efficient; and (3) dark energy has effects at all image separation
scales. While current lens samples cannot usefully constrain all of the
parameters, ongoing and future imaging surveys should discover hundreds or
thousands of lenses and make it possible to disentangle the various effects and
constrain all of the parameters simultaneously. (abridged)Comment: 15 pages, 11 figures, accepted for publication in Ap
The quasar Q0957+561: Lensed CO emission from a disk at z~1.4?
In recent years large efforts have been made to detect molecular gas towards
high redshifted objects. Up to now the literature reports on only two cases of
CO-detection in quasars at a redshift between 1 and 2 - Q0957+561, a
gravitationally lensed system at z=1.41 (Planesas et al. 1999), and HR10 at
z=1.44 (Andreani et al. 2000). According to Planesas et al. (1999), 12CO(2-1)
emission was detected towards both the lensed images of Q0957+561 with the IRAM
Plateau de Bure Interferometer (PdBI). In contrast to the optical spectra of
the two images which support the idea that they are images of one and the same
object, the CO-spectra were surprisingly different: the southern image (named
CO-B) shows a single blueshifted line whereas a double-peaked line profile with
a blue- and a redshifted part appears towards the northern image (CO-A). Based
on the observations and on simulations with a gravitational lens program, we
are tempted to argue that the line profile traces the presence of molecular gas
of a disk in the host galaxy around the quasar. We have now new observations
with the PdBI providing the necessary sensitivity to corroborate our disk
model.Comment: 4 pages, 1 figure, to appear in "Proceedings of the 4th
Cologne-Bonn-Zermatt-Symposium", ed. S. Pfalzner, C. Kramer, C. Straubmeier,
and A. Heithausen (Springer Verlag
Hepatic amoebiasis
Thirty-two cases of hepatic amoebiasis with some unusual features are presented. The clinical spectrum and the value of investigations such as liver scanning, angiography and slide agglutination test are presented. Therapy is outlined.S. Afr. Med. J., 48, 1159 (1974
Detection of microgauss coherent magnetic fields in a galaxy five billion years ago
Magnetic fields play a pivotal role in the physics of interstellar medium in
galaxies, but there are few observational constraints on how they evolve across
cosmic time. Spatially resolved synchrotron polarization maps at radio
wavelengths reveal well-ordered large-scale magnetic fields in nearby galaxies
that are believed to grow from a seed field via a dynamo effect. To directly
test and characterize this theory requires magnetic field strength and geometry
measurements in cosmologically distant galaxies, which are challenging to
obtain due to the limited sensitivity and angular resolution of current radio
telescopes. Here, we report the cleanest measurements yet of magnetic fields in
a galaxy beyond the local volume, free of the systematics traditional
techniques would encounter. By exploiting the scenario where the polarized
radio emission from a background source is gravitationally lensed by a
foreground galaxy at z = 0.439 using broadband radio polarization data, we
detected coherent G magnetic fields in the lensing disk galaxy as seen 4.6
Gyrs ago, with similar strength and geometry to local volume galaxies. This is
the highest redshift galaxy whose observed coherent magnetic field property is
compatible with a mean-field dynamo origin.Comment: 29 pages, 5 figures (including Supplementary Information). Published
in Nature Astronomy on August 28, 201
Golden gravitational lensing systems from the Sloan Lens ACS Survey. I. SDSS J1538+5817: one lens for two sources
We present a lensing and photometric study of the exceptional system SDSS
J1538+5817, identified by the SLACS survey. The lens is a luminous elliptical
at redshift z=0.143. Using HST public images in two different filters, the
presence of two background sources lensed into an Einstein ring and a double
system is ascertained. Our new spectroscopic observations, performed at the
NOT, reveal that the two sources are located at the same redshift z=0.531. We
investigate the total mass distribution of the lens between 1 and 4 kpc from
the galaxy center by means of parametric and non-parametric lensing codes that
describe the multiple images as point-like objects. Several disparate lensing
models agree on: (1) reproducing accurately the observed image positions; (2)
predicting a nearly axisymmetric total mass distribution, centered and oriented
as the light distribution; (3) measuring a value of 8.11 x 10^{10} M_{Sun} for
the total mass projected within the Einstein radius of 2.5 kpc; (4) estimating
a total mass density profile slightly steeper than an isothermal one. A fit of
the SDSS multicolor photometry with CSP models provides a value of 20 x 10^{10}
M_{Sun} for the total stellar mass of the galaxy and of 0.9 for the fraction of
projected luminous over total mass enclosed inside the Einstein radius. By
combining lensing and photometric mass measurements, we differentiate the lens
mass content in terms of luminous and dark matter components. This
two-component modeling, which is viable only in extraordinary systems like SDSS
J1538+5817, leads to a description of the global properties of the galaxy dark
matter halo. Extending these results to a larger number of lenses would improve
considerably our understanding of galaxy formation and evolution processes in
the LCDM scenario.Comment: 21 pages, 16 figures, accepted by The Astrophysical Journa
PG 1115+080: variations of the A2/A1 flux ratio and new values of the time delays
We report the results of our multicolor observations of PG 1115+080 with the
1.5-m telescope of the Maidanak Observatory (Uzbekistan, Central Asia) in
2001-2006. Monitoring data in filter R spanning the 2004, 2005 and 2006 seasons
(76 data points) demonstrate distinct brightness variations of the source
quasar with the total amplitude of almost 0.4 mag. Our R light curves have
shown image C leading B by 16.4d and image (A1+A2) by 12d that is inconsistent
with the previous estimates obtained by Schechter et al. in 1997 - 24.7d
between B and C and 9.4d between (A1+A2) and C. The new values of time delays
in PG 1115+080 must result in larger values for the Hubble constant, thus
reducing difference between its estimates taken from the gravitational lenses
and with other methods. Also, we analyzed variability of the A2/A1 flux ratio,
as well as color changes in the archetypal "fold" lens PG 1115+080. We found
the A1/A2 flux ratio to grow during 2001-2006 and to be larger at longer
wavelengths. In particular, the A2/A1 flux ratio reached 0.85 in filter I in
2006. We also present evidence that both the A1 and A2 images might have
undergone microlensing during 2001-2006, with the descending phase for A1 and
initial phase for A2. We find that the A2/A1 flux ratio anomaly in PG 1115 can
be well explained both by microlensing and by finite distance of the source
quasar from the caustic fold.Comment: 14 pages, 7 figures, 8 tables, Accepted for publication in MNRA
Late noninvasive evaluation of cardiac performance in mildly symptomatic older patients with Ebstein's anomaly of tricuspid valve: Role of radionuclide imaging
AbstractTen patients 8 to 54 years of age with isolated Ebstein's anomaly of the tricuspid valve were evaluated by electrocardiography, maximal exercise treadmill testing, 24 h electrocardiographs (ECG) monitoring, echocardiography and rest radionuclide imaging of the left ventricle. The patients presented after the 1st year of life and had not undergone surgical intervention. All except one were in functional class II. No patient had preexcitation on the surface ECG, but abnormal tachyarrhythmias or bradyarrhythmias were seen in five patients on 24 h ECG monitoring. Subnormal exercise performance was observed in five patients.Echocardiography demonstrated typical variable tricuspid valve displacement and paradoxic interventricular septal motion. Left ventricular end-diastolic dimensions were normal in all patients, but posterior wall motion was reduced in two. Moderate to severe tricuspid regurgitation with a Doppler jet velocity <2.5 m/s was demonstrated in eight patients. Left ventricular radionuclide scintigraphy revealed a subnormal ejection fraction (<50%) in 5 of 10 patients; these 5 had previously shown suboptimal exercise performance.The two youngest patients (<15 years) had no arrhythmia, normal exercise performance and normal left ventricular ejection fraction. There was no correlation between the degree of tricuspid valve displacement or régurgitation and the presence of rhythm disturbance, exercise performance or radionuclide left ventricular function.Late evaluation of patients with Ebstein's anomaly may demonstrate significant unsuspected abnormalities in cardiac rhythm, exercise performance and left ventricular function. Radionuclide scintigraphy is a useful noninvasive technique for assessing left ventricular dysfunction in these patients
Forest carbon projects in the Ukrainian carpathians: An assessment of potential community impacts and benefits
Reducing emissions from deforestation and degradation (REDD+) is a frequently promoted climate change mitigation strategy. As forest carbon projects proceed, we are learning how they affect local sovereignty and resource access, particularly in developing economies. Central and Eastern Europe’s temperate forests offer potential for projects, yet little is known about how the sociopolitical context of these transitional economies may influence project success. In this article, we enhance understanding of potential community impacts and explore opportunities for fair benefit distribution in Ukraine’s Carpathian Mountain region. Through a thematic qualitative and interpretive analysis of interviews and observational data, we: (1) describe what community-level forest uses and tenure rights may be affected by forest carbon projects; and (2) explore the opportunities and obstacles of fair benefit distribution and community engagement in projects in the region. Our data show that local communities in the region are important forest-dependent stakeholders, relying on the forest for fuelwood, non-timber forest products, recreation, and other intangible benefits. This indicates the need for strong social safeguards in developing forest carbon projects. While no mechanisms exist for direct revenue sharing, communities could derive other benefits that improve the local social, economic, and ecological situation. Our results further suggest that lessons from projects in developing economies can be informative to project development in post-socialist, transitioning economies
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