The Fresh-Finger Property

The unified property roughly states that searching for an element is fast when the current access is close to a recent access. Here, "close" refers to rank distance measured among all elements stored by the dictionary. We show that distance need not be measured this way: in fact, it is only necessary to consider a small working-set of elements to measure this rank distance. This results in a data structure with access time that is an improvement upon those offered by the unified property for many query sequences

Molecular Hydrogen emission from disks in the eta Chamaeleontis cluster

Disks in the 6 Myr old cluster eta Chamaeleontis were searched for emission from hot H2. Around the M3 star ECHAJ0843.3-7905 we detect circumstellar gas orbiting at ~2 AU. If the gas is UV-excited, the ro-vibrational line traces a hot gas layer supported by a disk of mass ~0.03Msolar, similar to the minimum mass solar nebula. Such a gas reservoir at 6 Myr would promote the formation and inwards migration of gas giant planets.Comment: Accepted for publication in MNRAS. 9 page

Child Abuse and Neglect in the UK Today

This report presents new research findings from the NSPCC on child maltreatment in the United Kingdom, looking specifically at the prevalence and impact of severe maltreatment. We found that the rates of child maltreatment reported by young adults aged 18–24 were lower in 2009 than in 1998, suggesting maltreatment may be less prevalent today. However, significant minorities of children and young people in the UK today are experiencing severe maltreatment and this is associated with poorer emotional wellbeing, self-harm, suicidal ideation and delinquent behaviour