12,198 research outputs found
Leukocyte extract reduces HIV replication and modulates cellular factors involved in HIV infection: therapeutic meant
Efficacy and safety of the patient empowerment through predictive personalised decision support (pepper) system: an open-label randomised controlled trial
ALMA CN Zeeman Observations of AS 209: Limits on Magnetic Field Strength and Magnetically Driven Accretion Rate
While magnetic fields likely play an important role in driving the evolution of protoplanetary disks through angular momentum transport, observational evidence of magnetic fields has only been found in a small number of disks. Although dust continuum linear polarization has been detected in an increasing number of disks, its pattern is more consistent with that from dust scattering than from magnetically aligned grains in the vast majority of cases. Continuum linear polarization from dust grains aligned to a magnetic field can reveal information about the magnetic field´s direction, but not its strength. On the other hand, observations of circular polarization in molecular lines produced by Zeeman splitting offer a direct measure of the line-of-sight magnetic field strength in disks. We present upper limits on the net toroidal and vertical magnetic field strengths in the protoplanetary disk AS 209 derived from Zeeman splitting observations of the CN 2-1 line. The 3σ upper limit on the net line-of-sight magnetic field strength in AS 209 is 5.0 mG on the redshifted side of the disk and 4.2 mG on the blueshifted side of the disk. Given the disk´s inclination angle, we set a 3σ upper limit on the net toroidal magnetic field strength of 8.7 and 7.3 mG for the red and blue sides of the disk, respectively, and 6.2 and 5.2 mG on the net vertical magnetic field on the red and blue sides of the disk. If magnetic disk winds are a significant mechanism of angular momentum transport in the disk, magnetic fields of a strength close to the upper limits would be sufficient to drive accretion at the rate previously inferred for regions near the protostar.Fil: Harrison, Rachel. University of Illinois at Urbana; Estados UnidosFil: Looney, L. W.. University of Illinois at Urbana; Estados UnidosFil: Stephens, I. W.. Harvard-Smithsonian Center for Astrophysics; Estados UnidosFil: Li, Z.-Y.. University of Virginia; Estados UnidosFil: Teague, Richard. Department Of Astronomy; Estados UnidosFil: Crutcher, Richard. University of Illinois at Urbana; Estados UnidosFil: Yang, H.. Tsinghua University; ChinaFil: Cox, E. G.. Northwestern University; Estados UnidosFil: Fernandez Lopez, Manuel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; ArgentinaFil: Shinnaga, H.. Kagoshima University; Japó
NSVS06507557; a low-mass double-lined eclipsing binary
In this paper we present the results of a detailed spectroscopic and
photometric analysis of the V=13.4 low-mass eclipsing binary NSVS 06507557
with an orbital period of 0.515 d. We obtained a series of mid-resolution
spectra covering nearly entire orbit of the system. In addition we obtained
simultaneous VRI broadband photometry using a small aperture telescope. From
these spectroscopic and photometric data we have derived the system's orbital
parameters and determined the fundamental stellar parameters of the two
components. Our results indicate that NSVS 06507557 consists of a K9 and an M3
pre-main-sequence stars with masses of 0.660.09 \Msun and 0.280.05
\Msun and radii of 0.600.03 and 0.440.02 \Rsun, located at a distance
of 1119 pc. The radius of the less massive secondary component is larger
than that of the zero-age main-sequnce star having the same mass. While the
radius of the primary component is in agreement with ZAMS the secondary
component appers to be larger by about 35 % with respect to its ZAMS
counterpart. Night-to-night intrinsic light variations up to 0.2 have been
observed. In addition, the H, H lines and the forbidden
line of [O{\sc i}] are seen in emission. The Li{\sc i} 6708 \AA absorption line
is seen in most of the spectra. These features are taken to be the signs of the
classic T Tauri stars' characteristics. The parameters we derived are
consistent with an age of about 20 Myr according to the stellar evolutionary
models. The spectroscopic and photometric results are in agreement with those
obtained by theoretical predictions.Comment: 21 pages, 9 figures. Accepted by MNRA
A Primer on Resonances in Quantum Mechanics
After a pedagogical introduction to the concept of resonance in classical and
quantum mechanics, some interesting applications are discussed. The subject
includes resonances occurring as one of the effects of radiative reaction, the
resonances involved in the refraction of electromagnetic waves by a medium with
a complex refractive index, and quantum decaying systems described in terms of
resonant states of the energy. Some useful mathematical approaches like the
Fourier transform, the complex scaling method and the Darboux transformation
are also reviewed.Comment: 28 pages, 9 figures, lectures presented at the Advanced Summer School
in Physics 2008, Cinvestav, Mexic
In processu Petri Ludovici Gan super apprehensione de la Baronia de Torrellas, en el incidente de la reposicion, por Don Miguel de Torrellas y Bardaxi, Lopez, Ferna-dez de Heredia y Pomar
Precede al texto viñeta con la inscripción: "Jesus, Maria, Joseph"Precede a p.1, 1 h. pleg. con el arbol de la sucesión a la Baronia de TorrellasCopia digital : Diputación Provincial de Zaragoza. Servicio de Archivos y Bibliotecas, 2010Datos de tít, tomados de p.1 y mención de responsabilidad del final del textoTexto fechado al final del mismo en Zaragoza 1703Sign.: A-E\p2\sInic. grab. en p.
Can disordered mobile phone use be considered a behavioral addiction? An update on current evidence and a comprehensive model for future research
Despite the many positive outcomes, excessive mobile phone use is now often associated with potentially harmful and/or disturbing behaviors (e.g., symptoms of deregulated use, negative impact on various aspects of daily life such as relationship problems, and work intrusion). Problematic mobile phone use (PMPU) has generally been considered as a behavioral addiction that shares many features with more established drug addictions. In light of the most recent data, the current paper reviews the validity of the behavioral addiction model when applied to PMPU. On the whole, it is argued that the evidence supporting PMPU as an addictive behavior is scarce. In particular, it lacks studies that definitively show behavioral and neurobiological similarities between mobile phone addiction and other types of legitimate addictive behaviors. Given this context, an integrative pathway model is proposed that aims to provide a theoretical framework to guide future research in the field of PMPU. This model highlights that PMPU is a heterogeneous and multi-faceted condition
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