We report a novel experimental technique for the comparison of ionization processes in ultrafast laser pulses irrespective of pulse ellipticity. Multiple ionization of xenon by 50 fs 790 nm, linearly and circularly polarized laser pulses is observed over the intensity range 10 TW/cm 2 to 10 PW/cm 2 using Effective Intensity Matching (EIM), which is coupled with Intensity Selective Scanning (ISS) to recover the geometry-independent probability of ionization. Such measurements, made possible by quantifying diffraction effects in the laser focus, are compared directly to theoretical predictions of multiphoton, tunnel and field ionization, and a remarkable agreement demonstrated. EIM-ISS allows the straightforward quantification of the probability of recollision ionization in a linearly polarized laser pulse. Furthermore, probability of ionization is discussed in terms of the Keldysh adiabaticity parameter γ, and the influence of the precursor ionic states present in recollision ionization is observed for the first time.

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In recent years there have been many studies of multiple ionization of closed shell rare gas atoms by intense laser fields. Until now no similar work has been done in the study of more diverse targets such as negative ions where low binding energies and strong electron correlations could yield distinctive behaviour. We present the first results of ionization of more than one electron from a range of atomic negative ions by intense laser pulses. Although these pulses are long by modern standards, and tend to produce sequential ionization in atoms, the positive ion yields from the negative ions do not depend predictably on the ionization potentials. This suggests that there may, intriguingly, be an alternative mechanism enhancing double ionization at low intensities.

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It is increasingly recognized that patients with cardiovascular disease may also suffer from concurrent psychological problems. Many patients present to emergency services and cardiologists with a history of panic disorder. Because of the similarity of presenting symptoms, these patients are often undiagnosed and consequently have slower recovery times and are costly to the healthcare system. Panic disorder is a significant public health problem; however, it is a treatable condition. Healthcare providers should be aware of its occurrence in cardiovascular disease. This case study describes the use of psychosocial interventions, such as the cognitive behavior therapy, in the management of panic disorder after coronary artery bypass graft. A 64-year-old man was treated with 9 sessions of cognitive behavior therapy over a 5-month period. Baseline assessment showed significant distress and deficit in functioning. Following intervention, there was marked reduction in objective and subjective measurement of distress and overall improvement in functioning. Healthcare providers, particularly nurses, need to consider the integration of psychosocial interventions into areas of critical care to provide effective and holistic care. Preoperative screening would be helpful as well.