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Abstract  

Radioisotope induced X-ray fluorescence analysis is a rather simple and convenient method for investigating ashed plant material. In order to reduce matrix effects, thin samples (2 mg/cm2) are analyzed to obtain a reasonable compromise between maximum sensitivity and the lowest possible absorption effects. Concentrations are determined by standard addition method. A precision of 6–8% can be achieved. As an application, analytical results are given for whole grains of several sorts of wheat.

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Abstract  

We have been working on mercury collection from flue gas by amalgamation and subsequent XRF analysis. Previous results showed unexpectedly high relative standard deviation (30%) in collection efficiency when silver-coated filters were exposed to gas phase mercury in a pilot-scale test chamber. Filters were analyzed by micro-XRF, TXRF and conventional XRF to explore the source of scattering. It was concluded that mercury had inhomogeneously adsorbed in the filter as the cause of this variation, leading to a positive bias of 50% in efficiency value. Results reported in this paper suggest the TXRF method is accurate to within ±10% when X-ray counting statistics are not the limiting factor. Application of this filter in flue gas measurement will be presented.

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We studied the early vegetation dynamics in former croplands (sunflower and cereal fields) sown with a low-diversity seed mixture (composed of 2 native grass species) in Egyek-Pusztakócs, Hortobágy National Park, East-Hungary. The percentage cover of vascular plants was recorded in 4 permanent plots per field on 7 restored fields between 2006 and 2009. Ten aboveground biomass samples per field were also collected in June in each year. We addressed two questions: (i) How do seed sowing and annual mowing affect the species richness, biomass and cover of weeds? (ii) How fast does the cover of sown grasses develop after seed sowing? Weedy species were characteristic in the first year after sowing. In the second and third year their cover and species richness decreased. From the second year onwards the cover of perennial grasses increased. Spontaneously immigrating species characteristic to the reference grasslands were also detected with low cover scores. Short-lived weeds were suppressed as their cover and biomass significantly decreased during the study. The amount of litter and sown grass biomass increased progressively. However, perennial weed cover, especially the cover of Cirsium arvense increased substantially. Our results suggest that grassland vegetation can be recovered by sowing low diversity mixtures followed up by yearly mowing. Suppression of perennial weed cover needs more frequent mowing (multiple times a year) or grazing.

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Abstract

Kidney neoplasms can occur after kidney transplantation in low percentage. In this report we delineate a rare case of neoplasm in the transplanted kidney detected on screening ultrasonographic examination. Due to the intercalyceal location of the tumor percutaneous radiofrequency ablation was planned with continuous cooling the collecting system avoiding the thermal damage. To the best of our knowledge this method has never been reported applying in transplanted kidney. The two-month CT follow-up verified no residual tumor and the kidney function remained in normal range during this period. These facts imply that the method can be safely applied.

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Acta Botanica Hungarica
Authors: P. Török, E. Tóth, K. Tóth, O. Valkó, B. Deák, B. Kelbert, P. Bálint, Sz. Radócz, A. Kelemen, J. Sonkoly, T. Miglécz, G. Matus, A. Takács, V. A. Molnár, K. Süveges, L. Papp, L. Papp Jr., Z. Tóth, B. Baktay, G. Málnási Csizmadia, I. Oláh, E. Peti, J. Schellenberger, O. Szalkovszki, R. Kiss, and B. TÓthmérész

For understanding local and regional seed dispersal and plant establishment processes and for considering the ecotypes and other forms of specific variability, hard data of locally or regionally measured traits are necessary. We provided newly measured seed weight data of 193 taxa, out of which 24 taxa had not been represented in the SID, LEDA or BiolFlor databases. Our new measurements and formerly published data of locally collected seed weight records together covers over 70% of the Pannonian flora. However, there is still a considerable lack in seed weight data of taxonomically problematic genera, even though they are represented in the Pannonian flora with a relatively high number of species and/or subspecies (e.g. Sorbus, Rosa, Rubus, Crataegus and Hieracium). Our regional database contains very sporadic data on aquatic plants (including also numerous invasive species reported from Hungary and neighbouring countries) and some rare weeds distributed in the southwestern part of the country. These facts indicate the necessity of further seed collection and measurements.

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Acta Botanica Hungarica
Authors: R. Kiss, J. Sonkoly, P. Török, B. Tóthmérész, B. Deák, K. Tóth, K. Lukács, L. Godó, A. Kelemen, T. Miglécz, Sz. Radócz, E. Tóth, N. Balogh, and O. Valkó

Seeds ensure the survival and dispersal of the majority of vascular plant species. Seeds require species-specific germination conditions and display very different germination capacities using different germination methods. Despite the importance of plant generative reproduction, little is known about the germination capacity of the seeds of the Pannonian flora, particularly under field conditions. Our aim was to reduce this knowledge gap by providing original data on the germination capacity of 75 herbaceous species. We reported the germination capacity of 8 species for the first time. We also highlighted the year-to-year differences in the germination capacity of 11 species which could be highly variable between years. The data regarding the germination capacity of target species, as well as weeds and invasive species, can be informative for nature conservation and restoration projects. Our findings support the composition of proper seed mixtures for ecological restoration and also highlight the importance of testing seed germination capacity before sowing.

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