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Abstract  

We prove that the family of all invariant sets of iterated systems of contractions R NR N is a nowhere dense F σ type subset in the space of the nonempty compact subsets of R N equipped with the Hausdorff metric.

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Acta Botanica Hungarica
Authors: Á. K. Kiss, L. Gy. Szabó, and K. Szabó

Komárek, J. and Anagnostidis, K. (2005): Cyanoprokaryota. 2. Teil: Oscillatoriales. - In: Büdel, B., Krienitz, L., Gärtner, G. and Schagerl, M. (eds): Süßwasserflora von Mitteleuropa, Band 19/2. Spektrum Akademischer Verlag, Elsevier GmbH, München, 759 pp.; Ross, I. A. (2005): Medicinal plants of the world - chemical constituents, traditional and modern medicinal uses. Volume 3. - Humana Press, Totowa, New Jersey, 623 pp. (ISBN 1-59259-887-0); Siver, P. A., Hamilton, P. B., Stachura-Suchoples, K. and Kociolek, J. P. (2005): Diatoms of North America: The freshwater flora of Cape Cod, Massachusetts, U.S.A. - In: Lange-Bertalot, H. (ed.): Iconographia Diatomologica. Annotated Diatom Micrographs. Vol. 14. A. R. G. Gantner Verlag K. G. Ruggel, 463 pp.;

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Secondary sexual characteristics such as softening and rounding of the abdomen as well as reddening and protrusion of the anal papilla and vent can be of help to breeders in selecting common carp (Cyprinus carpio) females prepared for propagation. To assess the reliability of this method, long-term data obtained on induced spawning of common carp at a large-scale fish hatchery were evaluated. The average spawning ratio of 2,620 females receiving hormonal injections was 79.8%. The average pseudogonadosomatic index (PGSI) calculated from data on the egg production of 2,086 females was 16.3 ± 5.87% (mean ± SD) for the same period. There was a correlation between fish weight and the time of induction determined by the breeder on the basis of external morphological characteristics. The similarity of the responses of females, including both spawning ratio and PGSI, among the different weight categories proved the reliability of this method for identification.

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Papaver somniferum produces secondary metabolites, which have important roles in their self-defence processes, in plant biochemistry and in allelochemistry. We can see that different stress effects change the quantity of alkaloids. The object of the experiments is, in what manner changes the content of alkaloids of poppy in case of irregular stress effects. Papaver somniferum (cv. 'Kék Duna', Budakalász) plants were grown for 2 months from seeds in quartz-sand (in natural light, temperature: 24-28 °C, in Knop's nutritive solution). In this paper we studied the alkaloid of poppy treated with two kind of stress factors: mycotoxin and drought, respectively. Both the quantity and the spectrum of alkaloids were measured after different separation procedures. Thin layer chromatography (TLC and HPTLC) and high performance liquid chromatography (HPLC) were applied. Content of the level of formaldehyde (HCHO) also increases in plants with different stress effects. Our presupposition is that the formation of methyl groups of poppy alkaloids takes place through HCHO. It gave us an opportunity to examine changing of formaldehyde (HCHO) level in biotic and abiotic stress situation. Formaldehyde in dimedone adduct form can be detected in injured tissues of Papaver somniferum. As a consequence, the stress effects can be detected in poppy plants by two kinds of method. At first we measured content of alkaloids. Drought stress produced a higher level of the alkaloids, but the mycotoxin stress did not show significant results.

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Abstract  

Formation of oxidizing and reducing radicals has been studied by pulse radiolysis of [Fe(CN)6]4––BrO 3 –CN system in ethylene glycol — water solvent mixture. Oxidizing ·BrO2 and BrO radicals formed by electron scavenging with ·BrO 3 were identified and their reactions were investigated. The reaction of hydroxyl radicals with ethylene glycol leads to formation of reactive radicals with reducing properties and of compounds which reduce slowly in dark the ferricyanide formed in the reaction of ·BrO2 radical with ferrocyanide.

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Acta Botanica Hungarica
Authors: M. Kumar Singh, L. Balogh, and K. Szabó

Sanita di Toppi, L. and Pawlik-Skowronska, B. (eds) (2003): Abiotic stresses in plants. - Kluwer Academic Publishers, Dordrecht, The Netherlands, 231 pp. (ISBN 1-4020-1648-4); Weber, E. (2003): Invasive plant species of the world: A reference guide to environmental weeds. - CAB International Publishing, Wallingford, 548 pp. (ISBN 0-85199-695-7); Werum, M. and Lange-Bertalot, H. (2004): Diatoms in springs from Central Europe and elsewhere under the influence of hydrogeology and anthropogenic impacts. pp. 9-417. Reichardt, E. (2004): Eine bemerkenswerte Diatomeenassoziation in einem Quellhabitat im Grazer Bergland, Österreich. pp. 419-480. - In: Lange-Bertalot, H. (ed.): Iconographia Diatomologica. Annotated Diatom Micrographs. Vol. 13. Ecology-Hydrogeology-Taxonomy. A. R. G. Gantner Verlag K. G. Ruggel, 480 pp.;

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The authors’ aim is to reveal the reflection of Hungarian political and economic transformation in the public health nutrition during the last two and a half decades. Results of the four representative, nationwide dietary surveys completed in this period have been analysed for macro-, micronutrient intakes and overweight/obesity. The food consumption-related vital statistics provided by Hungarian Central Statistical Office were also analysed and compared. There are certain signs of favourable improvements: slight decrease of energy intake in females, growing share of plant protein, less saturated, more polyunsaturated fatty acid intake, less sugar. These findings are in parallel with some positive general statistical issues: the extension of life expectancy, lesser acute myocardial infarction, atherosclerosis and stomach cancer mortality, more vegetables and fruit, lesser lard, more oil consumption. On the other hand, there are several detrimental nutritional issues that influence the health status of Hungarian population: still high energy, fat and cholesterol intake, low complex carbohydrates, too much sodium (salt), insufficiencies in some vitamin, macro- and microelements intake. The number of overweight/obese people takes up fairly high level. The surveys somewhat revealed the role of nutrition in the health status of population and now a particle of possibility for its improvement is available

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Abstract  

The influence of -radiation on the d.c. conductivity of poly(3-hexadecylthiophene) (PHDT) doped with FeCl3 in chloroform, toluene, ethanol and nitrobenzene atmospheres has been studied. A different course of d.c. conductivity changes taking place in the atmosphere of solvent vapors (chloroform, toluene) and precipitants (ethanol, nitrobenzene) has been found. The character of changes can be influenced by polymer cross-linking initiated by -radiation.

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