A simple resonance enhanced laser ionization scheme for CO via the A1Π state.

We investigate the laser ionization process taking place when the CO molecule is exposed to vacuum ultraviolet (VUV) radiation resonant with the CO A1Π(v = 0) ← X1Σ+(v = 0) transition around 154 nm, along with the ultraviolet (UV) and visible (Red) radiation used to generate VUV by four-wave difference-frequency mixing. By measuring the CO+ ion recoil and a room temperature gas spectrum, it is possible to assign the ionization process as 1 + 1' + 1'' REMPI where the one-photon steps refer to the VUV, UV, and Red radiation, respectively. Resonance enhanced ionization of rotational states around J = 12 arise due to the overlap of the fixed wavelength UV (∼250 nm) with the R band-head of a transition assigned to CO E1Π(v = 6) ← A1Π(v = 0) with a term value of 104 787.5 cm-1. The REMPI process is efficient and polarization sensitive and should be useful in a wide range of studies involving nascent CO.

Memory performance in acute and weight-restored anorexia nervosa patients.

BACKGROUND: Anorexia nervosa (AN), at the stage of starvation and emaciation, is characterized by abnormalities in cognitive function, including memory performance. It is unclear whether memory impairment persists or is reversible following weight restoration, and whether memory function differs between AN subtypes. The aim of the present study was to investigate general memory performance in currently ill and fully weight-restored patients of different AN subtypes. METHOD: Memory performance was assessed using the Wechsler Memory Scale-Revised (WMS-R) in a total of 99 participants, including 34 restricting-type AN patients (AN-RESTR), 19 binge-eating/purging-type AN patients (AN-PURGE), 16 weight-restored AN patients (AN-W-R) and 30 healthy controls (CONTROL). Cognitive evaluation included a battery of standardized neuropsychological tasks for validating the findings on memory function. RESULTS: Deficits were found with respect to immediate and delayed story recall in currently ill AN patients irrespective of AN subtype. These deficits persisted in weight-restored AN patients. Currently ill and weight-restored AN patients did not differ significantly from healthy controls with respect to working memory or other measures of neuropsychological functioning. CONCLUSIONS: The findings suggest that impaired memory performance is either a stable trait characteristic or a scar effect of chronic starvation that may play a role in the development and/or persistence of the disorder.