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Authors provide a 6-year study about aspects of development of Cameraria ohridella and its parasitoids in different leaf types of horse-chestnut trees. Investigations were carried out near Hédervár, North-West Hungary between 1999 and 2004.It was ascertained that in large leaves at low foliage levels as well as in large leaves exposed to direct sunlight developed more moths than in other leaf types of equal quantity (i.e. equal number of leaflets). On the other hand, there were not considerable differences between shaded and sun-exposed leaves in this regard if their quantity is measured in grams. Moreover, comparing the numbers of hatched moths per unit leaf weight, the values for minute leaves were the highest. The differences were explained on the basis of diverse microclimatic conditions in the mines, height preference of the moth or variations in dry weights per unit leaf area.Parasitism of Cameraria ohridella showed significant yearly differences between canopy levels and a tendency of changes during the years. Parasitism was higher in shaded than in sun-exposed leaves. Lowest values were found in minute leaves among all leaf types investigated what was explained with a presumed foraging behaviour of the parasitoids.Structure and species constitution of the parasitoid community and its changes in time are discussed in different leaf types. Temporal changes of several characteristics found in different leaf types refer to an adaptation process of the horse-chestnut leafminer.

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The horse-chestnut leafminer is a new pest which was established in North-West Hungary ca. 10 years prior to these investigations. Due to the very limited time, there are relatively few studies on the parasitoid community of the moth and its connection with the leafminer host. Authors used twig-isolators to find out which larval/pupal instars are mostly parasitized and by which chalcidoid species. They also made an attempt to calculate density curves of different developmental stages of the moth and to compare them with flight curves of the parasitoids. Experiences indicated that 4-week-old larval (pupal) instars were parasitized to the highest degree. The most frequent parasitoids were Pediobius saulius and Pnigalio agraules . Statements about a poor synchronization between moth and parasitoids were confirmed but possibility of a shift in swarming times on location was suggested. Different methods to calculate rate of parasitism were compared and evaluated.

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The heavy mineral assemblages and chemistry of detrital spinel grains from the Senonian basin of the Transdanubian Range (TR) were examined and compared with previous results from Jurassic and Lower Cretaceous successions of the Gerecse Mountains of the Transdanubian Range Unit. The heavy minerals recorded that in the area of Transdanubian Range the sedimentary cover, low-grade metamorphic and granitic rocks of the continental crust were eroded in the Coniacian and Santonian. Detritus of high-grade metamorphics was transported to the bathyal basin during Campanian time. The ophiolitic source area indicated by the presence of chrome spinel, ilmenite and magnetite still existed and persisted through the Late Cretaceous.  Compared to the low TiO2 content (lower than 0.2 wt%) of detrital spinels from Jurassic and Lower Cretaceous sediments of the Gerecse Mountains, the most characteristic features of spinels in the Senonian sediments are as follows: exceptionally high TiO2 content (about 0.5-4.7 wt%), relatively high amount of Cr2O3 (about 33-50.8 wt%) and high total iron (sumFeO=15-36 wt%). The data on detrital spinels from the Ajka Coal and Csehbánya Formations suggests that xenoliths (mainly dunites), which previously enclosed the spinel grains, may have been formed from alkalic-tholeiitic magma as crystal accumulates. This was the potential source rock of high TiO2-bearing spinel grains.

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This paper presents the so far only partially published research material of the late Bálint Zólyomi on one of his major fields of interest, the forest steppe vegetation. The phytosociological tables presented here were found in his bequest indicating that he was going to publish a grand synthesis on this topic, which, however, has not come true. Since no written text accompanied the original tables, a historical overview and a short explanation to the tables are also provided.

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Thermolysis of complex cyanides, XV

Decomposition of [Fe(CN)4 BIPY]n− and [Fe(CN)4 PHEN]n− complexes

Journal of Thermal Analysis and Calorimetry
Authors:
A. Horváth
,
B. Mohai
, and
F. Miko

The thermal decompositions of K2[Fe(CN)4 L]·4 H2O, H2[Fe(CN)4 L] and H[Fe(CN)L](L=1,1′-bipyridine, of 1,10-phenanthroline) were studied. The experimental results showed that the protonated ferrous complexes decompose with formation of HCN at lower temperature than the corresponding potassium salts. The decomposition of K2[Fe(CN)4 L] starts by removal of the ligand L. HCN elimination is followed by a redox reaction with formation of cyanogen in the case of H[FeIII(CN)4 L].

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Zs. Visy: A ripa Pannonica Magyarországon [Die ripa Pannonica in Ungarn]. Akadémiai Kiadó, Budapest 2000, 144 S., 180 Abb., 28 Karten; A. Pasquier (ed.): Olympie.Cycle de huit conférences or ganisé au Musée du Louvre par le Service Culturel du 18 janvier au 15 mars 1999, Paris. La documentation Française. Paris 2001, 282 s;

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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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The mechanisms leading to the development of eosinophilia were investigated in 65 patients with immunodermatological disorders, including the role of eosinophilotactic cytokines and the possible involvement of human T-cell leukemia virus, HTLV. HTLV-1 gag proviral sequences were revealed in two cases of lymphoproliferative disorders such as angiolymphoid hyperplasia with eosinophilia (ALHE) and CD4+ cutaneous lymphoma, respectively. Increased level of GM-CSF was detected in 33% of disorders studied. Elevated level of IL-5 and eotaxin was detected in 27% and 30%, respectively, of patients with bullous diseases. Elevated level of GM-CSF and eotaxin was found in 33% and 46%, respectively, of patients with inflammatory diseases. Neither of the four cytokines, however proved to be responsible alone or together for the induction of eosinophilia. The possible indirect role of human retroviruses through induction of eosinophilic chemotactic cytokines is hypothesized.

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Abstract  

The nuclear track technique (NTT) is used to enhance the porosity of silica micro-particles. The enhanced porosity is a result of the formation of surface and interior pores or tracks in the silica by the action of external and internal fission fragments. The fission tracks produced at the surface and within the interior of the micro-particles are a result of coating the particles with trace quantitities of uranium, instead of having trace quantities of uranium incorporated within the silica matrix.

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