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Tabula Hungariae (1528), created by Lazarus (Secretarius), is an almost 500 year-old map depicting the whole Pannonian Basin. It has been used for several geographic and regional science studies because of its highly valued information context. From geoscientific point of view this information can also be evaluated. In this contribution an attempt is made to analyse in some extent the paleo-hydrogeography presented in the map, reconsidering the approach of previous authors, assuming that the mapmaker did not make large, intolerable errors and the known problems of the cartographic implementation are rather exceptional.According to the map the major lakes had larger extents in the 16th century than today, even a large lake (Lake Becskerek) ceased to exist. Concerning the fluvial pattern, a detailed analysis is possible for the Danube. Important changes can be implied at the Danube Bend, and there was a stronger tendency of island formation (i.e., tendency towards braided style) downstream from the present day Budapest. In most of the cases the assumption of the depicted islands is feasible. The existence of a few paleo-islands not present today can be validated by historical sources as well. Furthermore, the river Sárvíz, today a less important watercourse, might have had more importance in the transport at that time, probably due to its larger water discharge.Summarizing the observations it seems that these are indications of larger discharge values and/or a wetter climate in the Central Pannonian Basin in the 16th century.

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Abstract  

Sufficient conditions of covariance type are presented for weighted averages of random variables with arbitrary dependence structure to converge to 0, both for logarithmic and general weighting. As an application, an a.s. local limit theorem of Csáki, Földes and Révész is revisited and slightly improved.

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The aim of this paper is to represent any continuous local martingale as an almost sure limit of a nested sequence of simple, symmetric random walk, time changed by a discrete quadratic variation process. One basis of this is a similar construction of Brownian motion. The other major tool is a representation of continuous local martingales given by Dambis, Dubins and Schwarz (DDS) in terms of Brownian motion time-changed by the quadratic variation. Rates of convergence (which are conjectured to be nearly optimal in the given setting) are also supplied. A necessary and sufficient condition for the independence of the random walks and the discrete time changes or equivalently, for the independence of the DDS Brownian motion and the quadratic variation is proved to be the symmetry of increments of the martingale given the past, which is a reformulation of an earlier result by Ocone [8].

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Acta Alimentaria
Authors: D. Székely, L. Szalóki-Dorkó, M. Stéger-Máté, B. Szabó-Nótin, J. Ivanics, and J. Monspart-Sényi

The beetroot is typically on the table in winter in form of pickles or juice, but for its nutritional values it would deserve more common consumption. Its curative effect in great part is due to the several vitamins, minerals, and compounds with antioxidant activity. But the division of biological active compounds is very different in the parts of the root. Based on our results, we could compare the differences between the morphology and some inner contents (soluble solid content, colour, betacyanin, betaxanthin, and polyphenol contents, antioxidant activity, and some flavonoids) of two beetroot cultivars. The results of the morphological investigations showed that the ‘Cylindre’ cultivar had more favourable crop parameters than the ‘Alto F1’ cultivar. In the ‘Cylindre’ cultivar the polyphenol content and the antioxidant capacity were significantly higher than in the ‘Alto F1’ cultivar. By determination of the betanin contents of the investigated beetroots, our results showed both betacyanin and betaxanthin contents were higher in the ‘Cylindre’ cultivar. The chlorogenic acid, gallic acid, the cumaric acid have been identified based on the peaks of HPLC in the studied beetroot cultivars.

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Acta Biologica Hungarica
Authors: L. Horváth, Cs. Székely, Zs. Boczonádi, E. Mészáros, M. Bercsényi, B. Urbányi, and T. Müller

European eel is a catadromous fish species, which means that after living in freshwater premature individuals adapt to sea water, and migrate to the Sargasso Sea for spawning. Although male eel can be sexually matured even in freshwater, to date, it was believed that female eel can be matured only in seawater. Here we show that the process of sexual maturation may be induced in freshwater by treating female eels with carp pituitary (GSI = 9.87±1.55%). It is thus proposed that seawater condition is not an obligatory environment for stimulating gametogenesis and for artificial maturation of the European eel in neither gender.

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Acta Physiologica Hungarica
Authors: N Szegedi, E Zima, M Clemens, A Szekely, RG Kiss, G Szeplaki, L Geller, B Merkely, Z Csanadi, and G Duray

Background

Catheter ablation is a proven therapy of focal atrial tachycardia. However limited information is available about the additional value of electroanatomical over conventional mapping methods for this specific arrhythmia.

Methods

Consecutive catheter ablation procedures of FAT were analyzed in two cardiology centres. Only conventional mapping was used in 30 of the 60 procedures whereas additionally CARTO mapping was performed in another 30 procedures. Acute, six-month success rate, and procedural data were analyzed.

Results

Localization of ectopic foci is congruent with previously published data. There was no statistically significant difference between procedure time and fluoroscopy time using additionally CARTO mapping, compared to conventional mapping only. Acute success rate was higher in procedures guided by CARTO mapping than in procedures based on conventional mapping (27/30 vs. 18/30, p = 0.0081). During the 6-month follow-up period there was a better outcome (p = 0.045) in case of CARTO guided procedures (success: 11 cases, partial success: 12 cases, failure: 4 cases) compared to conventional mapping (success: 4 cases, partial success: 18 cases, failure: 7 cases).

Conclusions

Catheter ablation of focal atrial tachycardias using the CARTO electroanatomical mapping system seems to provide higher acute and 6-month success rate compared to ablation using conventional mapping methods only.

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