The spin-orbit alignment of the transiting exoplanet WASP-3b from Rossiter-McLaughlin observations

We present an observation of the Rossiter-McLaughlin effect for the planetary system WASP-3. Radial velocity measurements were made during transit using the SOPHIE spectrograph at the 1.93-m telescope at Haute-Provence Observatory. The shape of the effect shows that the sky-projected angle between the stellar rotation axis and planetary orbital axis (?) is small and consistent with zero within . WASP-3b joins the ~two-thirds of planets with measured spin-orbit angles that are well aligned and are thought to have undergone a dynamically gentle migration process such as planet-disc interactions. We find a systematic effect which leads to an anomalously high determination of the projected stellar rotational velocity (vsini = 19.6+2.2-2.1kms-1) compared to the value found from spectroscopic line broadening (vsini = 13.4 +/- 1.5kms-1). This is thought to be caused by a discrepancy in the assumptions made in the extraction and modelling of the data. Using a model developed by Hirano et al. designed to address this issue, we find vsini to be consistent with the value obtained from spectroscopic broadening measurements (vsini = 15.7+1.4-1.3kms-1).

Making Sense of Leaving Care: The contribution of Bridges Model of Transition to Understanding the Psycho-social process.

This paper is based on research into the transition of young people leaving public care in Romania. Using this specific country example, the paper aims to contribute to present understandings of the psycho-social transition of young people from care to independent living by introducing the use of Bridges (2002) to build on existing theories and literature. The research discussed involved mixed methods design and was implemented in three phases: semi-structured interviews with 34 care leavers, focus groups with 32 professionals, and a professional-service user working group. The overall findings confirmed that young people experience two different, but interconnected transitions - social and psychological - which take place at different paces. A number of theoretical perpectives are explored to make sense of this transition including attachment theory, focal theory and identity. In addition, a new model for understanding the complex process of transitions was adapted from Bridges’ (2002) to capture the clear complexity of transition which the findings demonstrated in terms of their psycho-social transition. The paper concludes with messages for leaving and after care services with an emphasis on managing the psycho-social transition from care to independent living.

A material model for multiaxial stretching and stress relaxation of polypropylene under process conditions

Polypropylene sheets have been stretched at 160 °C to a state of large biaxial strain of extension ratio 3, and the stresses then allowed to relax at constant strain. The state of strain is reached via a path consisting of two sequential planar extensions, the second perpendicular to the first, under plane stress conditions with zero stress acting normal to the sheet. This strain path is highly relevant to solid phase deformation processes such as stretch blow moulding and thermoforming, and also reveals fundamental aspects of the flow rule required in the constitutive behaviour of the material. The rate of decay of stress is rapid, and such as to be highly significant in the modelling of processes that include stages of constant strain. A constitutive equation is developed that includes Eyring processes to model both the stress relaxation and strain rate dependence of the stress. The axial and transverse stresses observed during loading show that the use of a conventional Levy-Mises flow rule is ineffective, and instead a flow rule is used that takes account of the anisotropic state of the material via a power law function of the principal extension ratios. Finally the constitutive model is demonstrated to give quantitatively useful representation of the stresses both in loading and in stress relaxation.

Using Process Algebra to Model Radiation Induced Bystander Effects

Radiation induced bystander effects are secondary effects caused by the production of chemical signals by cells in response to radiation. We present a Bio-PEPA model which builds on previous modelling work in this field to predict: the surviving fraction of cells in response to radiation, the relative proportion of cell death caused by bystander signalling, the risk of non-lethal damage and the probability of observing bystander signalling for a given dose. This work provides the foundation for modelling bystander effects caused by biologically realistic dose distributions, with implications for cancer therapies.