RESUMEN
Quantum beat spectroscopy is combined with triple-resonance vibrational overtone excitation to measure the Stark coefficients (SCs) of the water molecule for 28 rovibrational levels lying from 27,600 to 41,000 cm(-1). These data provide a stringent test for assessing the accuracy of the available potential energy surfaces (PESs) and dipole moment surfaces (DMSs) of this benchmark molecule in this energy region, which is inaccessible by direct absorption. SCs, calculated using the combination of a high accuracy, spectroscopically determined PES and a recent ab initio DMS, are within the 1% accuracy of available experimental data for levels below 25,000 cm(-1), and within 4.5% for coefficients associated with levels up to 35,000 cm(-1). However, the error in the computed coefficients is over 60% for the very high rovibrational states lying just below the lowest dissociation threshold, due, it seems, to lack of a high accuracy PES in this region. The comparative analysis suggests further steps, which may bring the theoretical predictions closer to the experimental accuracy.
RESUMEN
A 14 year old girl, at age 8, had had a bipolar pulse generator implanted with myocardial leads. Because one of the myocardial leads fractured near the electrode, a second pair of myocardial leads were implanted. Thus, the patient had two pairs of myocardial leads and one demand pulse generator implanted. When the patient was readmitted to the hospital because of light-headedness, the ECG monitor revealed frequent suppression of pulse generator pulses when hand pressure was exerted over the pulse generator site. Converting the pulse generator into the asynchronous mode with a magnet prevented inhibition. The pacemaker pocket was reopened. The pulse generator could not be inhibited either by pulling on the active myocardial leads or by moving the pulse generator, but the pulse generator could be inhibited by manipulation of the inactive leads which produced electrical signals having amplitudes and frequencies which were in the bandwidth of the sensing circuit. The probable cause of the electrical signals was the irregular contact of the terminals of the inactive leads with the patient's abdominal muscles. Replacement of the demand pulse generator by an asynchronous type resulted in cessation of the patient's light-headedness.