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  • Author or Editor: S. Horváth x
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The effects of cAMP-elevating compounds IBMX (3-isobutyl-1-methyl­xanthine) and isoproterenol, and that of rutin (an effective superoxide scavenger) were studied on orthovanadate- (a putative protein-phosphotyrosine phosphatase inhibitor) induced nitric oxide (NO) production in J774A.1 mouse macrophage cells. As we previously reported (Koncz and Horváth, 2000), rutin and sodium orthovanadate act synergistically to induce production of high amount of NO in J774A.1 cells. IBMX, an agent that can elevate cAMP level in the cells, can reduce the production of both the LPS- and rutin + orthovanadate-induced NO in macrophages. In contrast, isoproterenol, a non-selective ß-adrenergic receptor agonist, that reduced the LPS-induced NO production in macrophage cells, was unable to reduce the rutin + orthovanadate-induced NO production without negatively affecting cell viability. Moreover, isoproterenol dramatically enhanced the orthovanadate-induced NO synthesis in J774A.1 cells. Our previous study clarified that rutin and orthovanadate, in a specific concentration ratio of both, were able to produce hydrogen peroxide (H2O2). Using 2',7'-dichlorofluorescein-diacetate as a marker for H2O2, isoproterenol alone induced its oxidation but the rutin plus orthovanadate-induced H2O2 production was reduced by isoproterenol. These observations have revealed that, in some cases, H2O2 and superoxide (O2 -) scavengers can act in a reverse mode on macrophage cells depending on the presence or absence of orthovanadate.

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The invasive gelechiid moth, potato tuberworm Phthorimaea operculella (Zeller, 1873) was first recorded in Hungary (Komló, Baranya County) and Northern Croatia (Lug, Osijek-Baranja County) in December 2015. This quarantine species has not been reported from Hungary so far and it was known in Croatia only from the coastal region. The occurrence of Ph. operculella in the Carpathian basin is of great concern as this invader is able to cause negative impacts on the Hungarian potato cultivation. This occurrence of the species is one of the northernmost data in Europe so far.

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Abstract  

We prove that the tolerance lattice TolA of an algebra A from a congruence modular variety V is 0-1 modular and satisfies the general disjointness property. If V is congruence distributive, then the lattice Tol A is pseudocomplemented. If V admits a majority term, then Tol A is 0-modular.

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This article presents a new, simple and rapid embryo biopsy method. The blastomere for genetic analysis can be separated from a precompacted mouse embryo after a partial zona digestion with the use of a holding pipette. For the micromanipulation only two microcapillaries and micromanipulators are needed. The development of the biopsied embryos was studied during in vitro culture and in utero following embryo transfer. There was no significant difference between the treated and the control groups in the ratio of embryos that developed to the blastocyst stage, although the biopsied embryos were delayed in their development because they contained significantly fewer cells compared to the control ones at the same stage. Although there was no difference in the ratio of implantation, the development of the biopsied embryos in utero was also delayed 12-24 hours on the 9th day of pregnancy. No difference in development was visible from the 13th day of pregnancy. Statistically, no differences were found in the developmental ratio (number of developed fetuses/transferred embryos) of the control and treated embryos during gastrulation (9th day of pregnancy), at the beginning of organogenesis (13th day of pregnancy) and before birth (19th day of pregnancy). The embryo biopsy method presented here can be a new and useful tool for preimplantation genetic diagnosis.

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The coat protein (CP) gene from a necrotic strain of potato virus Y (PVY) has been engineered into two-old Hungarian cultivars, namely cv. Mindenes and Somogyi kifli. The integration of the coat protein gene was confirmed by polymerase chain reaction (PCR) using genomic DNA preparations. The transcription and the expression of the integrated CP gene was followed by Northern and Western blot. The pathogene derived resistance was demonstrated by mechanical inoculation of the trans­formant plants after the transfer of the regenerants into soil. The efficiency of the virus protection varied between different potatoes ranging to complete protection to no protection. All plants were tested in field conditions under the special licence, given the competent authority instructed by the Hungarian gene technology act. In two consecutive years three Mindenes independent transformants proved to be highly resistant against two different strains of PVY in provocative experiment.

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Periodica Mathematica Hungarica
Authors: S. Horváth, J. Kollár, G. Székely and T. Matolcsi
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Conservation treatments often take place at the scale of vegetation stands and affect within-stand heterogeneity and coexistence patterns of species first. Therefore, it is important to capture changes in these characteristics of vegetation to assess response to treatments early. We propose a method based on Juhász-Nagy’s information theory models, which is capable of describing fine-scale spatial structure of plant communities and characterizes temporal processes as a function of spatial pattern. The proposed multiscale approach handles structural complexity and its dependence on spatial scales with the help of a few coenological descriptors and helps to reveal how fine-scale vegetation pattern affects dynamics. The information statistical functions used in our study (species combination diversity, FD and associatum, As ) characterize the scale-dependent variability of multispecies coexistence (structural complexity) and multispecies spatial dependence (the degree of spatial organization). The maxima of these functions and the related characteristic areas (plot sizes) can be used to construct an abstract coenostate space, where spatiotemporal processes (degradation, regeneration) can be followed. We demonstrate the usefulness of the proposed methods for detecting degradation and monitoring vegetation changes in different stands (18 seminatural and 13 slightly degraded stands) of Brachypodium pinnatum dominated wooded steppe meadows in Hungary. The information theory measures captured changes of fine-scale vegetation patterns that remained unexplored by species richness and Shannon diversity. The maximum values of information statistical measures and the related characteristic areas detected differences between seminatural and slightly degraded stands. In the coenostate space, seminatural stands appeared to be less variable compared to degraded ones. Seminatural stands from various geographic locations were less dispersed in this space, i.e., less heterogeneous than degraded ones. The two regions of the coenostate-space defined by the set of seminatural and degraded stands were significantly different. Furthermore, we conclude that the region containing seminatural stands can be regarded as a reference region in this abstract space. Temporal variation of seminatural and degraded stands was also clearly different. Therefore, we recommend the approach for exploring the actual dynamic states of vegetation stands to be treated and for following consequences of treatments in order to determine effectiveness of the conservation action.

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Abstract

The identification of property changes and damage in various structures is one of the major points in the engineering society. This work contains the method and results of a long-term aging process implemented by an experimental system. We applied a chemical and heat artificial aging test on metal and plastic pipes to indicate the degradation levels and results with suitable measuring instruments. During our measurements of aged pipes vibration tests were performed to get information about the changing of the vibration spreading properties of different materials. We were searching for information about the property changing of widely used pipe materials to estimate the rate of degradation and the service life of these instruments more accurately.

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