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Paola Testa

Publications and source records attributed to Paola Testa.

2 recordsLinked to original sources

Mitral supravalvular ring: a case report.

Supravalvular mitral stenosis is a rare condition characterized by an abnormal ridge, with one or two orifices, covering and obstructing the mitral valve. Preoperative diagnosis is difficult with transtoracic echo (TTE), angiography and magnetic resonance imaging (MRI). In this case, a 36-year-old male, was admitted to our Heart department: He experienced progressive dyspnea on effort and at rest. Diagnosis was made by transesophageal echocardiography which showed, on apical 4-chamber section, an annular structure attached since a membrane to the atrial wall anterior mitral valve leaflet and just proximal to the posterior mitral leaflet. Pre-operative identification of the supravalvular mitral ring is the target for obtaining good surgical results. Cineangiography and MRI both failed in reaching this objective, whereas, transesophageal echocardiography is the best method to identify this congenital heart disease. Using TEE the identification is not only possible but also easier.

Adult↗

The 'solar model problem' solved by the abundance of neon in nearby stars.

The interior structure of the Sun can be studied with great accuracy using observations of its oscillations, similar to seismology of the Earth. Precise agreement between helioseismological measurements and predictions of theoretical solar models has been a triumph of modern astrophysics. A recent downward revision by 25-35 per cent of the solar abundances of light elements such as C, N, O and Ne (ref. 2) has, however, broken this accordance: models adopting the new abundances incorrectly predict the depth of the convection zone, the depth profiles of sound speed and density, and the helium abundance. The discrepancies are far beyond the uncertainties in either the data or the model predictions. Here we report neon-to-oxygen ratios measured in a sample of nearby solar-like stars, using their X-ray spectra. The abundance ratios are all very similar and substantially larger than the recently revised solar value. The neon abundance in the Sun is quite poorly determined. If the Ne/O abundance in these stars is adopted for the Sun, the models are brought back into agreement with helioseismology measurements.

Journal Article↗