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  • Author or Editor: Cs. Varga x
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Abstract  

We prove the existence of multiple solutions of certain systems of hemivariational inequalities, using a recent idea of B. Ricceri. As a consequence of our main theorem we obtain the existence of multiple solutions of Schrödinger type systems. Another application involves the principle of symmetric criticality.

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The present study was carried out at a dune slack meadow near Mórahalom town in the Southern part of the Great Hungarian Plain. The area of the grassland is approximately 840,000 m 2 . The vegetation is mosaic-like in accordance with the variable microrelief and water content. The lower part of the grassland consists of various types of saltmarshes and wet meadows and at the upper microrelief, Pannonic sand steppe patches occur. True bug assemblages were sampled at 16 patches using 5×50 sweeps at each sampling site. The sampling was repeated three times in both 2007 and 2008. The area, the perimeter, the shape index of the sampled patches as well as the diversity of the surrounding patches were assessed as “landscape parameters”. The plant species number and diversity of the sampled patches were estimated from the data of 5×5 m coenological quadrats. Altogether 66,087 adult individuals belonging to 153 species were collected. The ordination methods showed that the true bug assemblages of the sampling patches differ from each other in accordance with the vegetation type. These assemblages differed in their species composition and diversity as well as in their assemblage structure. The results suggested that the vegetation type based on plant species composition determined the true bug assemblages.

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The polysialylated, embryonic form of the neuronal cell adhesion molecule (PSA-NCAM) is known to participate in a whole series of synaptic rearrangements even in adult animals. The possible role of this molecule in neuroplastic changes of the adult rat somatosensory cortex induced by unilateral transection of the infraorbital branch of the trigeminal nerve was studied with PSA-NCAM immunostaining at light microscopic level. Two- and three-month-old CFY albino rats were sacrificied on days 1, 4, 6, 14 and 21 following operation and PSA-NCAM immunoreaction was examined at three levels of the vibrissa-cortex neuraxis, namely, in the principal nucleus of the trigeminal nerve, in the ventral posteromedial nucleus of the thalamus and in the somatosensory cortex. The lower levels of the neuraxis remained free of PSA-NCAM labeling, similarly to control, intact animals. However, a large number of scattered small neurons became PSA-NCAM immunoreactive in layers IV–VI on both ipsi- and contralateral sides of the somatosensory cortex from day 6 onwards, suggesting a possible transynaptic regulation of NCAM sialylation state.

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Four important Hungarian common carp (Cyprinus carpio L.) breeds (Attala mirror, Attala scaled, Hortobágy scaled and Szeged mirror) harvested from different fish farms were analysed in this study. Main body indices, slaughter characteristics, fillet fat content, and conventional fish flesh quality characteristics were measured and compared. The slaughter value of the mirror strains tended to exceed that of the scaled type carps. For the calculated body indices (profile, cross-sectional, head and tail index) the influence of strain was statistically proven. Fillet fat content was significantly (P<0.01) affected by strains/ponds. The pH value of the fillet was significantly influenced by the strain as a fixed factor. Large, strain dependent variability was proven in fat content besides identical fillet dry matter contents. It was assumed that culture conditions and strain largely influence and lead to a marked variability of the body composition and flesh quality of the most important Hungarian fish species.

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Basket willow (Salix viminalis L.) was grown in open-field experiment. The brown forest soil (sand texture, pHKCl 7.7, humus 1.6%, CEC 11.5 cmolc/kg; Cd-0.11, Cu-7.1, Pb-8.1, Zn-25.0 mg/kg in aqua regia extract) was treated with municipal sewage sludge compost (MSSC) (25 t/ha wet weight, 12.8 t/ha dry weight in 2009; 50 and 100 t/ha wet weight, 25.4 t/ha and 50.8 t/ha dry weight in 2008). The MSSC was moderately contaminated with toxic metals (Cd-<0.5, Cu-140, Pb-19, Zn-440 mg/kg in aqua regia extract in 2008, and Cd-<0.5, Cu-299, Pb-69, Zn-865 mg/kg in aqua regia extract in 2009). Accumulation of Zn in treated willow leaves doubled 4 months after 25 t/ha MSSC application, while in treated twig tips 30% less Zn was found than in control. Zn (max. 133 mg/kg d.w.), Cd (max. 1.15 mg/kg d.w.) and Cu (max. 7.73 mg/kg d.w.) accumulations in leaves or twig tips of basket willow were 16 months after 50 or 100 t/ha MSSC application. Twenty months after MSSC application in the harvested twigs (shoots without leaves) of 50 or 100 t/ha MSSC-treated cultures the Zn concentrations were only 9.8–14.3% higher than in controls. We suppose that there is not a direct danger of considerable Zn accumulation in the bioash after incineration of MSSC-treated willow shoots in biomass power plants.

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Acta Alimentaria
Authors:
J. Varga
,
S. Kocsubé
,
Gy. Szigeti
,
V. Man
,
B. Tóth
,
Cs. Vágvölgyi
, and
T. Bartók

Black mould rot caused by black Aspergilli is an important post-harvest disease of onion worldwide. Usually Aspergillus niger is cited as the causative agent based on morphological criteria. In this study, the mycobiota and fumonisin contamination of mouldy onion bulbs purchased in Hungary were examined. All except one of the examined mouldy samples were found to be contaminated with black Aspergilli, which could be isolated both from the outer dry and the inner fleshy scales of onion bulbs. Species assignment of the isolates was carried out using sequence analysis of part of the calmodulin gene. Sequence data revealed that all 35 black Aspergilli isolated from onions belong to the Aspergillus awamori species. The range of fumonisin isomers present in the onion samples was also examined using reversed-phase high-performance liquid chromatography/electrospray ionization-ion trap mass spectrometry. Two of the examined onion samples were found to be contaminated with fumonisins at a rate of about 0.3 mg kg−1. This is the first report on fumonisin contamination of onion bulbs. The fumonisin isomers observed include fumonisins B2–4, 3-epi-FB4, iso-FB1 (FB6) and an iso-FB2,3 form. The range of fumonisin isomers detected in the onion bulbs indicates that probably A. awamori is responsible both for mould rot and fumonisin contamination of onions in Hungary.

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The aim of our study was to survey the geosmin (GSM) and 2-methylisoborneol (MIB) concentrations of the sediment and that of common carp (Cyprinus carpio) flesh in three different Hungarian fish farms (clayey, marshy, and sodic ponds).

Results showed that the concentrations of off-flavour compounds of the sediment and fish fillets were related to the natural environment. The GSM concentration of bottom soil samples was higher, than MIB in each fish farm. Both off-flavour compounds were the highest in the marshy fish pond and the lowest in the sodic pond. In case of fish flesh, significant differences were found between the farms in GSM level and fat content. In the fish flesh the same tendency was found as in the sediments, but surprisingly, MIB concentration was higher in the fillets, referring to accumulation.

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Fatty acid (FA) composition of the fillet and the intestinal content of dwarf common carp (Cyprinus carpio carpio) living in Lake Hévíz was determined in wintertime collected samples and results were compared to widespread literature data on carp. Fillet FA profile of the thermally adapted (28 °C) Hévíz dwarf carps differed from profiles originated from divergent culture and feeding conditions in the overall level of saturation. Fillet myristic acid proportions largely exceeded all literature data in spite of poor dietary supply. Fillet fatty acid results indicate the effects of thermal adaptation (high saturation level) and the correlative effects of feed components rich in omega-3 fatty acids, with special respect to docosahexaenoic acid. With the application of discriminant factor analysis the Hévíz sample was accurately differentiated from the literature data on carp fillet fatty acid profile, mostly based on C14:0, C18:1 n9, C18:2 n6, C20:1 n9 and C20:4 n6 FAs. In summary, fillet FA profile suggested thermal adaptation, location specificity and the ingestion of algal and bacterial material.

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Abstract

Tendencies of foodborne outbreaks show that the number of illnesses caused by Campylobacter spp. has been increasing recently in the European Union and in Hungary as well. However, the epidemiological statuses of Member States are diverse. There are several aspects to be investigated by competent authorities before the introduction of interventions. Methods supporting food safety decision making range from quick and easy techniques to complex, resource consuming approaches. The aim of the present study was the implementation of an evaluation and ranking system for a risk and its causes occurring in the broiler production chain. Data and information available in scientific literature were converted to a structured easy-to-use evaluation that supports decision making and helps structured data processing.

Open access
Acta Alimentaria
Authors:
E. Sedaghati
,
M. Nikkhah
,
R. Zare
,
K. Fotuhifar
,
S. Kocsubé
,
Cs. Vágvölgyi
, and
J. Varga

Ochratoxin A is a mycotoxin produced by Aspergillus and Penicillium species. This mycotoxin is a common contaminant of various foods including cereal products, spices, dried fruits, coffee, beer and wine. Besides species assigned to Aspergillus section Circumdati, black Aspergilli including A. niger, A. carbonarius and A. sclerotioniger are also able to produce this mycotoxin. Black Aspergilli have been found to be the predominant fungi contaminating pistachio nuts worldwide. We examined the species distribution of black Aspergilli on Iranian pistachio nuts. Sequence-based identifications have been carried out using partial calmodulin sequence data. Our data indicate that instead of the potential ochratoxin and fumonisin producing A. niger species, A. tubingensis dominates on Iranian pistachio nuts. This species is unable to produce either of these mycotoxins, consequently do not contribute to mycotoxin contamination of pistachio nuts in Iran. Further studies are in progress to clarify the role of other Aspergilli in ochratoxin contamination of pistachio in Iran.

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