CDM accelerating cosmology as an alternative to Lambda CDM model

A new accelerating cosmology driven only by baryons plus cold dark matter (CDM) is proposed in the framework of general relativity. In this scenario the present accelerating stage of the Universe is powered by the negative pressure describing the gravitationally-induced particle production of cold dark matter particles. This kind of scenario has only one free parameter and the differential equation governing the evolution of the scale factor is exactly the same of the Lambda CDM model. For a spatially flat Universe, as predicted by inflation (Omega(dm) + Omega(baryon) = 1), it is found that the effectively observed matter density parameter is Omega(meff) = 1 - alpha, where alpha is the constant parameter specifying the CDM particle creation rate. The supernovae test based on the Union data (2008) requires alpha similar to 0.71 so that Omega(meff) similar to 0.29 as independently derived from weak gravitational lensing, the large scale structure and other complementary observations.

DEVELOPMENT AND VALIDITY OF THE DISORDERED EATING ATTITUDE SCALE (DEAS)

The aim of this study was to develop and validate the Disordered Eating Attitude Scale to measure disordered eating attitudes, defined as abnormal beliefs, thoughts, feelings, behaviors, and relationship regarding food. Exploratory factor analysis was performed and internal consistency assessed in a sample of female university students (N=196). Convergent validity was acceptable based on statistically significant correlations with the Eating Attitude Test-26 and Restraint Scale. Known-groups validity was determined by comparing the student sample`s mean scores against scores of an eating disorder group (N=51). The Disordered Eating Attitude Scale comprises 25 questions and five subscales explaining 54.3% of total variance. The total scores differentiated student, bulimia, and anorexia groups. The scale should prove useful for evaluating eating attitudes in various population groups and eating disordered patients.

VALLEY SPLITTING AND g-FACTOR IN AlAs QUANTUM WELLS

Here we present the results of magneto resistance measurements in tilted magnetic field and compare them with calculations. The comparison between calculated and measured spectra for the case of perpendicular fields enable us to estimate the dependence of the valley splitting as a function of the magnetic field and the total Lande g-factor (which is assumed to be independent of the magnetic field). Since both the exchange contribution to the Zeeman splitting as well as the valley splitting are properties associated with the 2D quantum confinement, they depend only on the perpendicular component of the magnetic field, while the bare Zeeman splitting depends on the total magnetic field. This information aided by the comparison between experimental and calculated gray scale maps permits to obtain separately the values of the exchange and the bare contribution to the g-factor.