RESUMEN
We discuss the possibility of generating noncritical quadrature squeezing by spontaneous polarization symmetry breaking. We first consider Type II frequency-degenerate optical parametric oscillators but discard them for a number of reasons. Then we propose a four-wave-mixing cavity, in which the polarization of the output mode is always linear but has an arbitrary orientation. We show that in such a cavity, complete noise suppression in a quadrature of the output field occurs, irrespective of the parameter values.
RESUMEN
Long-term results of the surgical treatment of cardiac myxomas are not completely understood due to its recurrence. We review our experience in 27 operated cases with a follow-up to 22 years (mean 6.5 years), in order to throw light on results and review the problem of recurrence. One patient had a previous recurrent myxoma. At surgery we resect all the tumors and their attachment bases. We prefer a biatrial approach, ample resection and exploration of all cardiac chambers. Hospital mortality was 3.7% (1 case of associated aortic valve replacement) and late mortality 7%. Long-term results were satisfactory, without recurrences. The postoperative life expectancy of these patients seems similar to that of the normal population, except in cases of recurrence or associated valve replacement. Recurrence is very low (4.7% in 526 cases reported in the literature), except in the case of young patients and recurrent, familial, multiple or complex myxomas. The multigrowth potential of the tumor seems more important than an inadequate surgical resection.
