The value of the left apical cap in the diagnosis of aortic rupture: a prospective and retrospective study.

The authors conducted a prospective and retrospective study of the radiographic findings in 45 patients with traumatic rupture of the aorta. In 7 cases, a left apical cap was the only clearly visible abnormality. In 11 cases a cap was present together with a poorly defined aortic knob, while in 13 cases both were seen along with mediastinal widening.

Experimental evidence of an x-ray laser.

A three-stage neodymium:glass laser has been used to produce collimated x-radiation from an aqueous copper(II) sulfate gel. The 1.06-mum Q-switch pulse from the neodymium laser was focused by a cylindrical lens to a horizontal line traversing a microscope slide sandwich that contained a thin film of gel.

Comparison of the X-ray crystallography of undecafluorocyclohexane, C(6)HF(11), with that of dodecafluorocyclohexane, C(6)F(12).

A comparison of undecafluorocyclohexane and dodecafluorocyclohexane shows that both exist at 23 degrees in face-centred cubic cells with edges a(0) = 10.00 +/- 0.02 A for C(6)HF(11) and a(0) = 10.