521 research outputs found
V1135 Herculis: a double-lined eclipsing binary with an Anomalous Cepheid
BVR light curves and radial velocities for the double-lined eclipsing binary
V1135\,Her were obtained. The brighter component of V1135\,Her is a Cepheid
variable with a pulsation period of 4.224330.00026 days. The orbital
period of the system is about 39.997820.00233 days, which is the shortest
value among the known Type\,II Cepheid binaries. The observed B, V, and R
magnitudes were cleaned for the intrinsic variations of the primary star. The
remaining light curves, consisting of eclipses and proximity effects, are
obtained. Our analyses of the multi-colour light curves and radial velocities
led to the determination of fundamental stellar properties of both components
of the interesting system V1135\,Her. The system consists of two evolved stars,
G1+K3 between giants and supergiants, with masses of M=1.4610.054
\Msun ~and M=0.5040.040 {\Msun} and radii of R=27.10.4
{\Rsun} and R=10.40.2 {\Rsun}. The pulsating star is almost filling
its corresponding Roche lobe which indicates the possibility of mass loss or
transfer having taken place. We find an average distance of d=7500450 pc
using the BVR magnitudes and also the V-band extinction. Location in the Galaxy
and the distance to the galactic plane with an amount of 1300 pc indicate that
it probably belongs to the thick-disk population. Most of the observed and
calculated parameters of the V1135\,Her and its location on the color-magnitude
and period-luminosity diagrams lead to a classification of an Anomalous
Cepheid.Comment: 25 pages, 9 Tables, 9 Figures, Accepted Revista Mexicana de
Astronom\'ia y Astrof\'isica. arXiv admin note: substantial text overlap with
arXiv:1211.120
Spin-polarized transport in ferromagnetic multilayered semiconductor nanostructures
The occurrence of inhomogeneous spin-density distribution in multilayered
ferromagnetic diluted magnetic semiconductor nanostructures leads to strong
dependence of the spin-polarized transport properties on these systems. The
spin-dependent mobility, conductivity and resistivity in
(Ga,Mn)As/GaAs,(Ga,Mn)N/GaN, and (Si,Mn)/Si multilayers are calculated as a
function of temperature, scaled by the average magnetization of the diluted
magnetic semiconductor layers. An increase of the resistivity near the
transition temperature is obtained. We observed that the spin-polarized
transport properties changes strongly among the three materials.Comment: 3 pages, 4 figure
Pooled Analysis of Resistance Patterns of Escherichia coli Strains Isolated From Urine Cultures in Turkey: Comparison of 1997–2001 and 2002–2007 Periods
WOS: 00026328780028
Colorado State University (CSU) accelerator and FEL facility
The Colorado State University (CSU) Accelerator Facility will include a 6-MeV L-Band (1.3 GHz) electron linear accelerator (linac) with a free-electron laser (FEL) system capable of producing Terahertz (THz) radiation, a laser laboratory, a microwave test laboratory, and a magnetic test laboratory. The photocathode-driven linac will be used in conjunction with a hybrid undulator capable of producing THz radiation. Here, a summary of the systems used at the CSU Accelerator Facility is discussed. The building construction is completed and equipment move-in has begun. The first beam is expected to occur by mid 2015
A rare cause of intraabdominal hematoma: rupture of mesenteric artery branch aneurysm
Superior mesenteric artery (SMA) aneurysm is the third most common splanchnic artery aneurysm. Unlike other splanchnic artery aneurysm, isolated aneurysms of the SMA branches are rare. They are usually asymptomatic and difficult to detect until they rupture and cause abdominal pain and hypovolemic shock. Thus, most cases are diagnosed after the occurrence of complications. In this report, we described a 76 year-old woman who had two saccular aneurysms in the superior mesenteric arterial branch(es). One of them was ruptured and partly thrombosed. The patient had acute renal failure secondary to massive intraabdominal hemorrhage
Hysteresis in the Random Field Ising Model and Bootstrap Percolation
We study hysteresis in the random-field Ising model with an asymmetric
distribution of quenched fields, in the limit of low disorder in two and three
dimensions. We relate the spin flip process to bootstrap percolation, and show
that the characteristic length for self-averaging increases as in 2d, and as in 3d, for disorder
strength much less than the exchange coupling J. For system size , the coercive field varies as for
the square lattice, and as on the cubic lattice.
Its limiting value is 0 for L tending to infinity, both for square and cubic
lattices. For lattices with coordination number 3, the limiting magnetization
shows no jump, and tends to J.Comment: 4 pages, 4 figure
Retrospective evaluation of clinical and pathological features, as well as diagnostic and treatment protocols of primary vaginal malignancy
Objectives: Our study aimed to determine the epidemiological characteristics and diagnostic and treatment protocols of primary vaginal carcinoma. Also, we compared the clinical and pathological features of primary vaginal carcinoma which intersect with cervical and vulvar carcinomas.
Material and methods: Sixteen patients with primary vaginal carcinoma, admitted to the Department of Gynecologic Oncology, Izmir Tepecik Training and Research Hospital between January 1983 and December 2012, were evaluated retrospectively. FIGO (International Federation of Gynecology and Obstetrics) Surgical staging was performed. The SPSS (Statistical Package for Social Sciences) program was used for statistical analyses.
Results: The histological distribution of the 16 patients with primary vaginal carcinoma was as follows: 9 patients (56.3%) with squamous cell carcinoma (SCC), 5 (31.3%) with rhabdomyosarcoma, and 2 (12.5%) with adenocarcinoma.
Conclusion: The stage of the disease was found the be the main factor affecting the survival
Charge and spin distributions in GaMnAs/GaAs Ferromagnetic Multilayers
A self-consistent electronic structure calculation based on the
Luttinger-Kohn model is performed on GaMnAs/GaAs multilayers. The Diluted
Magnetic Semiconductor layers are assumed to be metallic and ferromagnetic. The
high Mn concentration (considered as 5% in our calculation) makes it possible
to assume the density of magnetic moments as a continuous distribution, when
treating the magnetic interaction between holes and the localized moment on the
Mn(++) sites. Our calculation shows the distribution of heavy holes and light
holes in the structure. A strong spin-polarization is observed, and the charge
is concentrated mostly on the GaMnAs layers, due to heavy and light holes with
their total angular momentum aligned anti-parallel to the average
magnetization. The charge and spin distributions are analyzed in terms of their
dependence on the number of multilayers, the widths of the GaMnAs and GaAs
layers, and the width of lateral GaAs layers at the borders of the structure.Comment: 12 pages,7 figure
- …