Generalized Slow Roll Conditions and the Possibility of Intermediate Scale Inflation in Scalar-Tensor Theory

Generalized slow roll conditions and parameters are obtained for a general form of scalar-tensor theory (with no external sources), having arbitrary functions describing a nonminimal gravitational coupling F(\phi), a Kahler-like kinetic function k(\phi), and a scalar potential V(\phi). These results are then used to analyze a simple toy model example of chaotic inflation with a single scalar field \phi and a standard Higgs potential and a simple gravitational coupling function. In this type of model inflation can occur with inflaton field values at an intermediate scale of roughly 10^{11} GeV when the particle physics symmetry breaking scale is approximately 1 TeV, provided that the theory is realized within the Jordan frame. If the theory is realized in the Einstein frame, however, the intermediate scale inflation does not occur.Comment: 14 pages, no figs. Accepted to Classical and Quantum Gravit

Time-resolved Spectroscopy of the M15 X-ray Binary AC211/X2127+119

We present time-resolved spectroscopy acquired during two epochs (spaced apart by ~15 days) of the eclipsing Low Mass X-ray Binary AC211/X2127+119 in the globular cluster M15. The spectra show variations in the HeII 4686 emission line not only modulated on the orbital period, but also on time-scales of a few days. During the first epoch of observation, the emission line shows a strong S-wave superimposed on the average double-peaked profile. The line exhibits no evidence of rotational disturbance at the orbital phases when the eclipse is observed in the optical continuum. During the second epoch, no double-peak or S-wave component is present. The HeI absorption lines detected by other authors are not present in our spectra. A Doppler image of the HeII 4686 for the first epoch supports the presence of the accretion disc. No hotspot is detected, although enhanced emission at V_X=30km/s, V_Y=160 km/s is observed. We discuss the implications of this emission in the context of an X-ray heated donor star, in which case a high mass ratio and neutron star primary are implied. Finally, we speculate on the possibility of a misaligned secondary star in AC211.Comment: 12 pages, 5 figures, accepted by MNRA

Adsorption of proteins to thin-films of PDMS and its effect on the adhesion of human endothelial cells

This paper describes a simple and inexpensive procedure to produce thin-films of poly(dimethylsiloxane). Such films were characterized by a variety of techniques (ellipsometry, nuclear magnetic resonance, atomic force microscopy, and goniometry) and used to investigate the adsorption kinetics of three model proteins (fibrinogen, collagen type-I, and bovine serum albumin) under different conditions. The information collected from the protein adsorption studies was then used to investigate the adhesion of human dermal microvascular endothelial cells. The results of these studies suggest that these films can be used to model the surface properties of microdevices fabricated with commercial PDMS. Moreover, the paper provides guidelines to efficiently attach cells in BioMEMS devices.Fil: Chumbimuni Torres, Karin Y.. The University of Texas at San Antonio; Estados UnidosFil: Coronado, Ramon E.. The University of Texas at San Antonio; Estados UnidosFil: Mfuh, Adelphe M.. The University of Texas at San Antonio; Estados UnidosFil: Castro Guerrero, Carlos. The University of Texas at San Antonio; Estados UnidosFil: Silva, María Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Negrete, George R.. The University of Texas at San Antonio; Estados UnidosFil: Bizios, Rena. The University of Texas at San Antonio; Estados UnidosFil: Garcia, Carlos D.. The University of Texas at San Antonio; Estados Unido

On the binary nature of 1RXS J162848.1-415241

We present spectroscopy of the optical counterpart to 1RXS J162848.1-41524, also known as the microquasar candidate MCQC J162847-4152. All the data indicate that this X-ray source is not a microquasar, and that it is a single-lined chromospherically active binary system with a likely orbital period of 4.9 days. Our analysis supports a K3IV spectral classification for the star, which is dominant at optical wavelengths. The unseen binary component is most likely a late-type (K7-M) dwarf or a white dwarf. Using the high resolution spectra we have measured the K3 star's rotational broadening to be vsini = 43 +/- 3 km/s and determined a lower limit to the binary mass ratio of q(=M2/M1)>2.0. The high rotational broadening together with the strong CaII H & K / Halpha emission and high-amplitude photometric variations indicate that the evolved star is very chromospherically active and responsible for the X-ray/radio emission.Comment: 15 pages, 5 figures, accepted for publication in Ap

EPIDEMIOLOGICAL STUDY OF SPANISH RECREATIONAL RUNNERS

The objective of this study was to analyze how different training aspects and biological factors in running affect the probability of suffering an injury and which muscles and joints are more susceptible to develop an injury. A total of 408 subjects, 206 cases and 202 controls, participated in the investigation. The inferior body was more prone to an injury, especially the muscles and tendons associated with the knee and the shank. Several characteristics of the runner and his/her training habits like the sex, age, experience, motivation and mileage have an impact on the injury risk. This information is very useful because biomechanists and coaches can design programs to improve the technique of the runners and reduce the risk of an injury