Generation of Large Vortex-Free Superfluid Helium Nanodroplets.

Superfluid helium nanodroplets are an ideal environment for the formation of metastable, self-organized dopant nanostructures. However, the presence of vortices often hinders their formation. Here, we demonstrate the generation of vortex-free helium nanodroplets and explore the size range in which they can be produced.

Phase-of-the-Phase Electron Momentum Spectroscopy on Single Metal Atoms in Helium Nanodroplets.

Magnesium atoms fully embedded in helium nanodroplets are exposed to two-color laser pulses, which trigger multiphoton above-threshold ionization (ATI). This allows exemplary study of the contribution of a dense, neutral, and finite medium on single electron propagation. The angular-resolved photoelectron spectra show striking differences with respect to results obtained on free atoms.

Comparison of Electron and Ion Emission from Xenon Cluster-Induced Ignition of Helium Nanodroplets.

The charging dynamics of helium droplets driven by embedded xenon cluster ignition in strong laser fields is studied by comparing the abundances of helium and highly charged Xe ions to the electron signal. Femtosecond pump-probe experiments show that near the optimal delay for highly charged xenon the electron yield increases, especially at low energies. The electron signature can be traced back to the ionization of the helium environment by Xe seed electrons.

Cardiovascular screening with electrocardiography and echocardiography in collegiate athletes.

Background: Current guidelines for preparticipation screening of competitive athletes in the US include a comprehensive history and physical examination. The objective of this study was to determine the incremental value of electrocardiography and echocardiography added to a screening program consisting of history and physical examination in college athletes.

Methods: Competitive collegiate athletes at a single university underwent prospective collection of medical history, physical examination, 12-lead electrocardiography, and 2-dimensional echocardiography.

The impact of arrhythmias in acute heart failure.

Background: Arrhythmias are common in chronic heart failure and affect outcomes. The incidence and significance of new arrhythmias in acute heart failure, however, are largely unknown.

Methods And Results: The Outcomes of a Prospective Trial of Intravenous Milrinone for Exacerbations study randomized 949 patients with decompensated heart failure to receive intravenous milrinone or placebo.

Depressive Disorder in Older Medical Inpatients on General Medicine and Cardiology Services at a University Teaching Hospital.

The authors examined the prevalence, characteristics, and correlates of depressive disorder among medical inpatients age 60 or over at a private teaching hospital. Seventy-six of 129 patients admitted to the general medicine and cardiology services at Duke University Hospital were screened for depressive disorder using DSM-III-R criteria. Depressive disorders were diagnosed in 34.