High-Energy Vacuum Birefringence and Dichroism in an Ultrastrong Laser Field.

A long-standing prediction of quantum electrodynamics, yet to be experimentally observed, is the interaction between real photons in vacuum. As a consequence of this interaction, the vacuum is expected to become birefringent and dichroic if a strong laser field polarizes its virtual particle-antiparticle dipoles. Here, we derive how a generally polarized probe photon beam is influenced by both vacuum birefringence and dichroism in a strong linearly polarized plane-wave laser field.

The Dynamic Albedo of Neutrons (DAN) experiment for NASA's 2009 Mars Science Laboratory.

We present a summary of the physical principles and design of the Dynamic Albedo of Neutrons (DAN) instrument onboard NASA's 2009 Mars Science Laboratory (MSL) mission. The DAN instrument will use the method of neutron-neutron activation analysis in a space application to study the abundance and depth distribution of water in the martian subsurface along the path of the MSL rover.

CT cystography versus conventional cystography in evaluation of bladder injury.

Objective: The objective of this study was to evaluate prospectively the use of CT cystography, using retrograde filling of the bladder with diluted iodinated contrast material, versus conventional cystography to identify bladder injury in patients with hematuria after blunt abdominal trauma.

Subjects And Methods: Inclusion criteria consisted of the adult hemodynamically stable abdominal trauma patient with hematuria referred for abdominopelvic CT and also being considered for cystography. An initial abdominopelvic CT scan using IV iodinated contrast material was obtained, as would have been done routinely in the trauma victim.

Emphysematous pyelonephritis: a 5-year experience with 13 patients.

Emphysematous pyelonephritis is a life-threatening necrotizing renal infection characterized by the production of gas. Of 8,105 admissions to our diabetes service during the last 5 years we identified 13 cases. The patients were managed aggressively with fluids and antibiotics, followed by immediate nephrectomy.

Staghorn calculis: its clinical presentation, complications and management.

There were 95 patients (105 kidneys) with staghorn calculi evaluated clinically and 84 kidneys were studied on a pathologic basis. Only 1 percent of the patients could be defined as having a silent stone calculus. Clinical complications occurred in 53 per cent of the patients.