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Abstract  

For the selective removal of the matrix activity (24Na,32P and42K) in the neutron activation analysis of biomedical samples the inorganic separators “hydrated antimony pentoxide”, zirconium phosphate, and titanium phosphate were prepared. The sorption parameters of the samples were determined via elution chromatography techniques, with appropriate tracers. The basic principles of the sorption processes were investigated, and the experimental conditions were optimized. These inorganic separators were then applied, combined with a distillation procedure and an ion-exchange separation, for the determination of the following trace elements in animal blood samples: Mn, Co, Cu, Fe and Zn.

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Abstract  

The complexes of six organic carboxylic acids (containing {O,O} donor atoms) with Bu2Sn(IV)2+ and Ph3Sn(IV)+ with ligand to metal ratios of 1 : 1 and 1 : 2, were prepared by two different methods. The FtIR and Raman spectra clearly demonstrated that the organotin(IV) moieties react with the {O,O} atoms of the ligands. It was found that in most cases the -COO-group was chelated to the central metal ions, but monodentate coordination was also sometimes observed. Complex formation was accompanied by a rearrangement of the hydrogen-bonding network existing in the ligands. The complexes probably have polymeric structures. Comparison of the experimental Mössbauer D values with those calculated on the basis of the point charge model formalism revealed that the organotin(IV) moiety has a trigonal-bipyramidal (tbp) geometry, and in certain cases a tetrahedral (tetr) geometry too. Finally, the local structure of the maleic acid complex formed with Bu2Sn(IV)2+ was determined by an EXAFS method.

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Abstract  

The complexes of four oxime analogues of amino acids and peptides (containing {O,N} donor atoms) with Bu2SnO were prepared, with ligand to metal ratios of 1 : 1 or 1 : 2, by two different methods. The FT-IR and Raman spectra clearly demonstrated that the organotin(IV) moieties react with the {O,N} atoms of the ligands. It was found that in most cases the -COO- group is coordinated to the central metal ion in a monodentate mode. Complex formation was accompanied by a rearrangement of the hydrogen-bonding network existing in the ligands. The complexes probably have monomeric structures. Comparison of the experimental Mössbauer values with those calculated on the basis of the point charge model (pqs) formalism revealed that the organotin(IV) moiety has octahedral (oct) geometry, and in certain cases trigonal-bipyramidal (tbp) geometry too.

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Abstract  

A number of complexes of ligands containing {O,N,S} donor atoms (2,3,4,6-tetra-O-acetyl-b-D-thioglucopyranoside, 1-thio-b-D-glucose, 2-aminomercaptopurine, 4-amino-2-mercaptopyrimidine and 2-amino-6-mercaptopurine-9-D-riboside) with di-n-butyltin(IV) oxide, diphenyltin(IV) oxide, tribenzyltin(IV) chloride, and trimethyltin(IV) chloride were prepared in the solid state. It was found that the complexes contain the organotin(IV) moiety and the ligand in a ratio of 1:1 or 2:1. The FTIR and Raman spectra clearly demonstrated that the organotin(IV) moieties react with the {S} atom of the ligands, while di-n-butyltin(IV) oxide is coordinated to the deprotonated hydroxy group. In several cases, the basic part of the ligands also participates in complex formation. Comparison of the experimental Mössbauer D values with those calculated on the basis of the pqs concept revealed that the organotin(IV) moiety has trigonal-bipyramidal geometry, and in certain cases tetrahedral geometry too. Some of the complexes contain the organotin(IV) cation in two different surroundings.

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Acta Microbiologica et Immunologica Hungarica
Authors: L. Kredics, Zsuzsanna Antal, A. Szekeres, L. Hatvani, L. Manczinger, Cs. Vágvölgyi and Erzsébet Nagy

Cellulolytic, xylanolytic, chitinolytic and b-1,3-glucanolytic enzyme systems of species belonging to the filamentous fungal genus Trichoderma have been investigated in details and are well characterised. The ability of Trichoderma strains to produce extracellular proteases has also been known for a long time, however, the proteolytic enzyme system is relatively unknown in this genus. Fortunately, in the recent years more and more attention is focused on the research in this field. The role of Trichoderma proteases in the biological control of plant pathogenic fungi and nematodes has been demonstrated, and it is also suspected that they may be important for the competitive saprophytic ability of green mould isolates and may represent potential virulence factors of Trichoderma strains as emerging fungal pathogens of clinical importance. The aim of this review is to summarize the information available about the extracellular proteases of Trichoderma. Numerous studies are available about the extracellular proteolytic enzyme profiles of Trichoderma strains and about the effect of abiotic environmental factors on protease activities. A number of protease enzymes have been purified to homogeneity and some protease encoding genes have been cloned and characterized. These results will be reviewed and the role of Trichoderma proteases in biological control as well as their advantages and disadvantages in biotechnology will be discussed.

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The analysis was conducted on the national database of the station tests carried out between May 1996 and February 2001, using the Hungarian Large White (LW) and Hungarian Landrace (LR) breeds, and the A-line of the Ka-Hyb hybrid (MLW). Days of test, total amount of feed consumed and valuable cuts were taken into the analysis to test the random distribution of the animals' phenotypic measurements and predicted breeding values across the contemporary groups of origin. The phenotypic measurements of all traits were clearly positively associated with the herds of origin (b = 0.52-1.08). Animals with favourable phenotypic measurements originated from better herds. On the contrary, the predicted breeding values seemed to be independent of the herd effects (b= -0.16-0.08) and suggested a possible random distribution across the contemporary groups.

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The chemical composition of maize makes it suitable for a wide range of nonconventional uses, including utilisation as a new source of energy for the 21st century as a raw material for biofuel. The aim of the experiments was to amalgamate the application of genetic markers with conventional breeding methods to produce maize hybrids whose starch content and ecostability satisfied the demands of industrial use, while having yield potential and agronomic traits on a par with those of hybrids currently cultivated. The chemical quality of 220 lines was evaluated using the NIR spectrometric technique, and the five maize inbred lines with the lowest and highest starch contents were selected for genetic marker studies. The variety identification of the lines was carried out using the isoenzymes stipulated by UPOV. The following SSR (simple sequences repeat) markers were tested: phi 095, umc 1057, nc 004, phi 096, nc 007, umc 1564, phi 85, y1 SSR, umc 1178, nc 009, phi 070, umc 1066, umc 1741, umc 1069, phi 033, phi 061, wx, phi 032, phi 084 and phi 062. The analysis of the fragment patterns revealed three SSR markers that appeared to be correlated with the starch content of the maize lines. These were the primer pairs y1 SSR, umc 1069 and phi 062 . These results are only of a preliminary nature, however, as the incorporation of starch is probably regulated by several genes, and the studies suggest it is also influenced by several environmental factors. It also appears likely that the bioethanol yield is determined not only by the starch content, but also by other parameters. Further research should thus be expanded to include investigations into the structural and fermentability traits of starch molecules, including the characterisation of these traits using genetic markers.

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The objectives of this study were to examine the correlation between factors of great significance for crop production, especially between irrigation and fertilization, and to evaluate the effects of irrigation and fertilization on maize yields over four growing seasons (2001-2004) in a long-term field experiment set up at the Látókép Experimental Station of the Centre for Agricultural Sciences of Debrecen University. The results showed that irrigation and fertilization were strongly correlated with the yield. The effect of irrigation depended on the natural water and nutrient supplies of the soil, and on the specific fertilizer rates. The results indicated that both fertilization and irrigation had a significant effect on the yield. The correlation between the year and the crop production factors was also significant. The yield-increasing effect of irrigation and fertilization differed significantly in the experimental years.

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The cultivation technologies for the dominant crops in Hungary need to be improved both in the interests of environmental protection and to reduce cultivation costs. A long-term research project was initiated in order to determine the feasibility of conservation tillage systems. The aim of the experiments was to evaluate conservation farming systems in Hungary in order to achieve more economical and more environment-friendly agricultural land use. Four tillage systems, namely conventional tillage (mouldboard plough), conservation tillage I (primary tillage with a J.D. Disk Ripper), conservation tillage II (primary tillage with a J.D. Mulch Finisher) and no tillage (direct drilling), were compared on a clay loam meadow soil (Vertisol). The physical condition of the experimental soils was evaluated using a hand-operated static cone penetrometer. Parallel with the measurement of penetration resistance, the moisture content of the soil was also determined. The grain yield of maize hybrids (Kincs SC [1999], Occitán SC [2000], Pr 37M34 SC [2001], DeKalb 471 SC [2002]) was measured using a plot combine-harvester. The analysis of soil conditions confirmed that if the cultivation depth and intensity are reduced the compaction of soil layers close to the surface can be expected. The decrease in yields (8-33%) in direct drilling (NT) and shallow, spring cultivated (MF) treatments, despite the higher available water content, can be explained partly by the compacted status of the 15-25 cm soil layer.

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A destructive seed-borne pathogen, formerly described as Pleospora papaveracea affects opium poppy (Papaver somniferum L.) plants, grown in Hungary, causing considerable qualitative and quantitative losses. The symptoms of the disease were frequently observed in the field between 1999 and 2006. Seventeen Hungarian isolates were obtained from poppy and cultures were established on malt extract agar from naturally infected seeds, diseased foliage, pods and stem. The pathogens proved to be Crivellia papaveracea and a distinct taxon, Brachycladium papaveris based on morphological characterization of conidia, conidiophores and cultures, moreover molecular investigation of the ITS region. Significant morphological differences were observed among the isolates originating from distinct plant parts, however, cultural characteristics were similar. Molecular studies revealed that morphological and cultural differences or similarities do not correspond with taxonomic position of the isolates. Morphological variation of the isolates mainly depended on their origin and might be explained with the differences of microclimatic conditions.

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