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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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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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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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It is a prime aim to ensure a suitable comfort level in case of office buildings. The productivity of office employees is directly influenced by the comfort. Thermal discomfort and poor indoor air quality deteriorate the intensity and quality of human work. We investigated the comfort in office buildings with on-site measurements during the summer season. The office buildings were operating with different HVAC (Heating, Ventilating and Air-Conditioning) systems: ducted fan-coil with suspended ceiling, installation, non-ducted fan-coil with floor-mounted installation, active chilled beam with fresh air supply.

We evaluated the thermal comfort under PMV (Predicted Mean Vote), PPD (Predicted Percentage of Dissatisfied), the local discomfort based on DR (Draught Rate) and the IAQ (Indoor Air Quality) based on carbon dioxide concentration. The comfort measurements were evaluated. The measurements were evaluated with scientific research methods, comfort categories based on the requirements of CR 1752. The results of this comparison were presented in this article.

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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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Rats were treated with a combination of insecticide agents in different timing schemes. In acute administration, 1/5 LD50 of the three insecticides: dimethoate, propoxur and cypermethrin, or their combination, was given once by gavage. In the developmental model, female rats received oral doses of 1/25 LD50 of the above insecticides in combination in three timing schemes including pregnancy and lactation. Responses in the somatosensory cortex and in the tail nerve, evoked by peripheral electric stimulation, were recorded in acute preparation under urethane anesthesia. It was tested whether the parameters of the cortical and peripheral evoked response are dependent on the frequency and whether this dependence is different in control and treated animals. The latency increase of the cortical responses with increasing stimulation frequency was significantly stronger in rats treated acutely with cypermethrin and the combination, and in rats receiving the combination during both intra- and extrauterine development. On the duration, the effects were less clear. Frequency dependent increase of the tail nerve action potential latency was significantly intensified by cypermethrin, and the amplitude decrease, by cypermethrin and dimethoate. Fatigue of this response during a stimulation series was also altered by the insecticides. Frequency dependence and fatigue possibly reflect the actual state of the nervous system and may have the potency to be developed to functional biomarkers.

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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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