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Acta Geodaetica et Geophysica Hungarica
Authors: K. I. Kis, P. T. Taylor, G. Wittmann, H. R. Kim, B. Toronyi and T. Mayer-Gürr

To solve a geophysical inverse problem means applying measurements to determine the parameters of the selected model. The inverse problem is formulated as the Bayesian inference. The Gaussian probability density functions are applied in the Bayes's equation. The CHAMP satellite gravity data are determined at the altitude of 400 km altitude over the South part of the Pannonian Basin. The model of interpretation is the right vertical cylinder. The parameters of the model are obtained from the minimum problem solved by the Simplex method.

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Acta Physiologica Hungarica
Authors: Éva Zöllei, Dóra Paprika, T Wittmann, A Rosztóczy, R Róka, Z Gingl and L Rudas

We compared the cardiovascular responses in 10 patients with established gastro-oesophageal reflux disease (Group 1) and 10 control subjects (Group 2) during oesophageal saline and 0.1 mol/l hydrochloric acid instillation. Indices of heart rate and blood pressure variability and baroreflex gain (derived from linear spontaneous sequences and cross spectral analysis) were calculated. In Group 1 the standard deviation of RR intervals (SDRR: 46 ms vs. 51 ms, p=0.030) and the root mean square of successive differences (RMSSD: 24 ms vs. 26 ms, p=0.027) were significantly lower during acid infusions, than during saline. We found no significant difference in minimum, maximum and mean RR intervals and systolic blood pressures and in the percentage of RR intervals, which differed from adjacent cycles by more than 50 ms (PNN50). The power spectra of RR intervals in the high frequency band tended to be lower during acid infusion (p=0.055). There was no significant difference in blood pressure spectra, neither in low nor in high frequency band. In Group 2 there was no significant difference between any parameters measured during acid and saline. The baroreflex gain was not changed during the studied conditions in any group.

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