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Kovács and Papšová (1986) described a Pelsonian conodont fauna from the base of the Misina Hill key geologic section (Mecsek Mts, South Hungary), extracted from the host-rock of a Schreyerites? binodosus specimen published by Detre (1973). In the present paper the conodont fauna of the entire key section is described on the basis of 26 samples (from No. Bh-1 to Bh-26). A detailed taxonomic review of Gondolella bulgarica, G. hanbulogi and G. bifurcata is given, which are distinguished at species level (following the detailed morphotaxonomic study by Germani 2000), although all morphological transitions between the three taxa are present. They are united into the "G. bulgarica Group". Correlated with the Pelsonian type sections in the Balaton Highland (Aszófo, Felsoörs), the entire exposed sections of the Bertalanhegy and Dömörkapu Limestone Members belong to the upper part of the Pelsonian, e.g. to the Binodosus Zone. The Illyrian evaporitic "Middle Muschelkalk" event appears to be represented by a hiatus in the Mecsek "Muschelkalk" succession.

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Fungi, in particular Aspergilli, are well known for their potential to overproduce a variety of organic acids. These microorganisms have an intrinsic ability to accumulate these substances and it is generally believed that this provides the fungi with an ecological advantage, since they grow rather well at pH 3 to 5, while some species even tolerate pH values as low as 1. 5. Organic acid production can be stimulated and in a number of cases conditions have been found that result in almost quantitative conversion of carbon substrate into acid. This is exploited in large-scale production of a number of organic acids like citric-, gluconic- and itaconic acid. Both in production volume as well as in knowledge available, citrate is by far the major organic acid. Citric acid (2-hydroxy-propane-1, 2, 3-tricarboxylic acid) is a true bulk product with an estimated global production of over 900 thousand tons in the year 2000. Till the beginning of the 20th century, it was exclusively extracted from lemons. Since the global market was dominated by an Italian cartel, other means of production were sought. Chemical synthesis was possible, but not suitable due to expensive raw materials and a complicated process with low yield. The discovery of citrate accumulation by Aspergillus niger led to a rapid development of a fermentation process, which only a decade later accounted for a large part of the global production. The application of citric acid is based on three of its properties: (1) acidity and buffer capacity, (2) taste and flavour, and (3) chelation of metal ions. Because of its three acid groups with pKa values of 3. 1, 4. 7 and 6. 4, citrate is able to produce a very low pH in solution, but is also useful as a buffer over a broad range of pH values (2 to 7). Citric acid has a pleasant acid taste which leaves little aftertaste. It sometimes enhances flavour, but is also able to mask sweetness, such as the aspartame taste in diet beverages. Chelation of metal ions is a very important property that has led to applications such as antioxidant and preservative. Moreover, it is a “natural” substance and fully biodegradable.

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The conodont fauna published by Bóna (1976) from the Triassic of Villány Hills has been revised. It contains an association of Gondolella bifurcata, G. bulgarica and G. hanbulogi, the same as from coeval basinal deposits of the adjacent Mecsek Hills (Kovács and Rálisch-Felgenhauer, this volume), thus the Upper Pelsonian age assignment by Bóna (1976) is confirmed.

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Studia Slavica
Authors:
Sándor János Tóth
,
Tünde Tuska
,
Erzsébet Uhrin
, and
Mária Zsilák

This paper is intended to be a summary analyzing the use of the Slovakian language in Tótkomlós. The joint study organized by the Research Institute for Linguistics at the Hungarian Academy of Sciences and the Research Centre of Slovaks in Hungary was based on the empiric questionnaire method and followed by the elaboration of statistic data. As a result of the research, interesting conclusions can be drawn regarding the interrelation of language choice, code switching, bilingualism, and attitudes towardsdialects.

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Cereal Research Communications
Authors:
Ferenc Simon
,
Miklós Nádasy
,
Zsolt Marczali
,
Erzsébet Nádasy
, and
Sándor Keszthelyi
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Acta Microbiologica et Immunologica Hungarica
Authors:
L. Karaffa
,
Erzsébet Fekete
,
Erzsébet Sándor
,
Adél Sepsi
,
B. Seiboth
,
A. Szentirmai
, and
C. P. Kubicek
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Acta Microbiologica et Immunologica Hungarica
Authors:
Gábor Görcsös
,
László Irinyi
,
László Radócz
,
Gábor Tarcali
, and
Erzsébet Sándor

The ascomycetous fungus Cryphonectria parasitica (Murr.) is one of the most important fungal pathogens of chestnut (Castanea sativa Mill.), causing chestnut blight. It is originated from Eastern Asia and was introduced into North America, and later into Europe. Almost 100 C. parasitica isolates were collected mainly from the Carpathian Basin to study their diversity and phylogenetic relationships. Three nuclear molecular markers were tested: (i) internal transcribed spacers (ITS), (ii) translation elongation factor 1 subunit alpha (tef1), and (iii) six microsatellite loci. The ITS region proved to be highly polymorphic but this kind of variability did not reflect the geographical regions of the isolates, while the tef1 sequences were identical in all isolates. Microsatellite haplotype diversity was relatively high (0.923–0.984) calculated for the fungal populations of the Carpathian Basin. This may have resulted from the multiple introductions from diverse origins of the populations, close to the first site of observation in Northern Italy. The BAPS analysis of the microsatellite markers occasionally grouped together samples from remote geographical origin, suggesting human assistance in the introduction of new C. parasitica haplotypes from distinct areas.

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