Occupancy of rotational population in molecular spectra based on nonextensive statistics

The procedure to obtain gas temperature in plasmas is to fit the experimental rotational spectrum to a theoretical one based on the Boltzmann distribution. For many systems a single distribution fails to account for the occupation of the levels. Researchers have improved the fitting by coupling two distributions and obtaining two distinct temperatures. They assigned the lowest temperature to the gas. Here, we show that these systems should be described by Tsallis nonextensive statistics and its unique associated temperature. Experimental and simulated spectra are tested and excellent agreement is obtained.

Permanent junctional reciprocating tachycardia in infants and children: effectiveness of medical and non-medical treatment

BACKGROUND

The aim of this study was to identify, in children affected by permanent junctional reciprocating tachycardia (PJRT), the effective treatment.

METHODS

Seventeen children (9 males, 8 females, mean age 59 +/- 62 months, median 24) affected by PJRT were referred to our Institute between the years 1987 and 2000.

RESULTS

Pharmacological therapy was successfully used in 14 patients: flecainide and propranolol in 5 of them, amiodarone alone in 5 and associated with propranolol in 2, propafenone alone in 1 and in association with sotalol in 1. These drugs were given for a mean period of 54.5 +/- 49.8 months with resolution of the cardiomyopathy in 7/7 patients. Treatment had been continued for 3-6 months and there were no side effects. Nine patients were treated with radiofrequency transcatheter ablation, after 78 +/- 53.5 months of medical treatment, at a mean age of 150 +/- 16 months. The shortest endocardial ventriculo-atrial (VA) interval during tachycardia was recorded in all cases at the coronary sinus ostium (mean value of local VA-surface RP' interval -38 ms, range -24/-55 ms). Successful ablation of the anomalous pathway was obtained at this site in all patients (mean watts delivered 26 +/- 3 W, mean T degrees 64 +/- 5 degrees C). During the follow-up period (mean 21 +/- 17 months) 2 patients with recurrences of PJRT underwent a second successful procedure.

CONCLUSIONS

PJRT in pediatric patients can be successfully treated with antiarrhythmic drugs, this may allow delay of the highly effective radiofrequency ablation treatment until the children have reached an adequate growth.