Enhanced RF Behavior Multi-Layer Thermal Insulation.

This paper shows that it is possible to exploit the modulated metasurface concept to control the unwanted coupling between antennas that are installed on the same satellite. The metasurface is combined with a Multi-Layer thermal Insulation blanket to reduce its specular reflection by spreading the energy incoherently in the surrounding space. In the design, sub-wavelength radiating elements printed on thin substrate have been used to make the metasurface response azimuthally independent, and to keep the weight of blanket down. The comparison between simulations and measurements confirms the validity of the idea.

Heart rate variability and functional severity of congestive heart failure secondary to coronary artery disease.

To investigate the behaviour of heart rate variability (HRV) with the advancing severity of heart failure (CHF) we studied 20 normal subjects and 80 coronary artery disease (CAD) patients in sinus rhythm. CAD patients were selected consecutively in order to form four equal groups of 20 subjects with different degrees of CHF according to the New York Heart Association (NYHA) functional classification. In each subject a 24 h ECG Holter tape was recorded and subsequently analysed to obtain measures of heart rate and HRV. We used several measures of HR and both spectral and non-spectral measures of HRV. Among these we employed the width of the R-R interval distribution over 24 h at three different heights (TV, 10%Var, 50%Var). The CAD group showed significantly lower HRV counts and smaller spectral components than controls. However, these differences were due to the presence of CHF rather than to CAD. Indeed, a progressive and significant increase in heart rate and a contemporary decrease in HRV was observed with the advancing severity of CHF. Class IV patients had the smallest HR variation; the spectral composition in this group was barely detectable. The decrease in time domain measures of HRV followed the increase in NYHA Class in a progressive and regular pattern, while the low frequency and high frequency spectral power showed the largest reduction from NYHA Class I to NYHA Class II patients. No significant change was demonstrated in NYHA Class I patients as compared to Controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence of anti-HCV antibodies in patients with chronic liver disease and its relationship to HBV and HDV infections.

The prevalence of anti-HCV, anti-HDV and of HBV markers has been investigated in a series of 209 consecutive patients (age 18-74 years) with chronic liver disease. Among 155 HBsAg negative patients (53 chronic hepatitis cases and 102 cirrhosis cases), anti-HCV were found in 69% of the cases. 67% of the 155 patients also carried anti-HBc, with no difference between patients positive or negative for anti-HCV. Among the 54 HBsAg positive patients, 10 (18.5%) also had anti-HCV, 22 (40.7%) were anti-HDV positive and 12 (22.2%) had serum HBV-DNA. One patient had concomitant anti-HDV and anti-HCV and another presented anti-HCV and serum HBV-DNA. 21/54 patients had liver cirrhosis on presentation and among these 17 (81%) were anti-HCV and/or anti-HDV positive. On the whole, 123/209 patients had liver cirrhosis on presentation and in 107 of them HCV infection may have played a role.

[Multiple coronary spasms in asymptomatic patient (author's transl)]. / Spasmi coronarici multipli in paziente asintomatico.

A 46 year old asymptomatic male showed ST elevations in the inferior leads during an occasional basal electrocardiogram. During an ECG monitoring at rest a high number of transient episodes of ischemic type was noted: all were unrelated to symptoms. During the same session the ST segment changes appeared either in inferior leads or antero-lateral leads in different episodes. The coronary arteriography revealed absence of significant coronary stenosis and multivessel spasms: the episodes of ischemic ECG changes disappeared only during nifedipine therapy. After a 4 year follow up period no symptoms or coronary events occurred.