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The effect of four NPK fertilizer rates (NPK[1:1:1]: 0, 300, 600, 900 kg active ingredients·ha -1 ) was studied on the growth of maize and on weed infestation - bio-mass production and nutrient uptake of weeds - in four replications in a 35-year old long-term maize continuous cropping field experiment (Keszthely, Hungary). The weed flora was recorded on 1 June, 2003 in the 6-8-leaf development stage of maize. The effect of the increasing rates of fertilizers was analyzed and evaluated from the results of biomass production as well as the nutrient uptake of weeds and maize, respectively. On the experimental plots 9 weed species were registered at the date of sampling, from which 4 species were perennial and 5 species were annual ones. All the weeds were collected from 1 m² areas of each plot and the different weed species were separated from each other. The fresh and dry weights of the canopy of maize and the different weed species were measured. The nutrient (NPK) contents of maize and weed samples were measured in the laboratory. Total and species scale nutrient concentration, as well as per-unit nutrient uptake of maize and weeds were compared. The increasing rates of mineral fertilizers had a significant effect on the biomass production and on the nutrient uptake of weeds. Significant differences were also found between the biomass production and nutrient uptake of the different weed species.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: G. Fürjes, G. Tóth, B. Peitl, R. Pórszász, B. Lelesz, R. Sári, A. Tóth, Z. Szilvássy, and J. Németh

Abstract  

In the present paper the development and application of a novel thrittene radioimmunoassay (RIA) are described. 125I-labeling of Tyr(0)-thrittene was performed by the iodogen-method and the mono-iodinated peptide, as RIA tracer, was separated by reversed-phase high performance liquid chromatography (HPLC). The RIA results show that the antiserum used in the radioimmunoassay turned to be C-terminal specific, without significant affinity to other members of the somatostatin peptide hormone family. Detection limit of the assay was 0.2 fmol/ml. This highly specific and sensitive thrittene RIA was used to investigate the distribution of thrittene in the rat gastrointestinal tract and other tissue samples. Different areas of the gastrointestinal tract and other tissues were removed from rats and after extraction the samples were processed for thrittene radioimmunoassay. Highest concentrations were found in the duodenum samples followed by jejunum and ileum, however, all the examined tissues contained highly enough thrittene for the measurement.

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Agrokémia és Talajtan
Authors: Tibor Tóth, T. Németh, T. Fábián, T. Hermann, E. Horváth, Z. Patocskai, F. Speiser, Sz. Vinogradov, and G. Tóth

An internet-based land valuation system is being developed to replace the scientifically obsolete Hungarian land valuation system, the so-called AK (“Gold Crown”) ratings. The new system is supported by a GIS and it is unique in its capability of providing an up-to-date index of soil quality and land value. The geographical information is provided by national map databases on genetic soil maps and soil attributes at the scale of 1:10.000, combined with cadastral maps, digital terrain model, topographic map, orthophotos of aerial photographs and agronomic field records. The automated algorithms are easy to update, can be made legally binding and can provide a transparent system for land taxation, calculation of subsidies, appropriation. Given that detailed (1:10,000 or finer) soil map coverage will be completed for all lands of Hungary (at date only 60% of the croplands have soil maps), this way a multifunctional system will be available that promotes an optimum use of land resources. 

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Agrokémia és Talajtan
Authors: G. Gelybó, E. Tóth, C. Farkas, Á. Horel, I. Kása, and Z. Bakacsi

Climate change is expected to have a vigorous impact on soils and ecosystems due to elevated temperature and changes in precipitation (amount and frequency), thereby altering biogeochemical and hydrological cycles. Several phenomena associated with climate change and anthropogenic activity affect soils indirectly via ecosystem functioning (such as higher atmospheric CO2 concentration and N deposition). Continuous interactions between climate and soils determine the transformation and transport processes. Long-term gradual changes in abiotic environmental factors alter naturally occurring soil forming processes by modifying the soil water regime, mineral composition evolution, and the rate of organic matter formation and degradation. The resulting physical and chemical soil properties play a fundamental role in the productivity and environmental quality of cultivated land, so it is crucial to evaluate the potential outcomes of climate change and soil interactions. This paper attempts to review the underlying long-term processes influenced by different aspects of climate change. When considering major soil forming factors (climate, parent material, living organisms, topography), especially climate, we put special attention to soil physical properties (soil structure and texture, and consequential changes in soil hydrothermal regime), soil chemical properties (e.g. cation exchange capacity, soil organic matter content as influenced by changes in environmental conditions) and soil degradation as a result of longterm soil physicochemical transformations. The temperate region, specifically the Carpathian Basin as a heterogeneous territory consisting of different climatic and soil zones from continental to mountainous, is used as an example to present potential changes and to assess the effect of climate change on soils. The altered physicochemical and biological properties of soils require accentuated scientific attention, particularly with respect to significant feedback processes to climate and soil services such as food security.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: I. Boros, G. Horváth, S. Lehel, T. Márián, Z. Kovács, J. Szentmiklósi, G. Tóth, and L. Trón

Abstract  

[11C]-labeled form of ten A2a adenosine receptor specific 8-styryl-7-methyl-xanthine derivatives ([11C]-caffeines) were synthesised by N-methylation of the corresponding 8-styryl-xanthine derivatives using [11C]-methyl iodide in optimized reaction conditions. The results show that the [11C]-methylations take place with excellent radiochemical yields (35–93%), and can be utilised easily in online preparations. These labeled ligands may facilitate the positron emission tomographic (PET) investigation of adenosine A2a receptors.

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Abstract  

The purpose of this investigation was to further elucidate calorimetric properties of cartilage samples from femoral head necrosis and osteoarthritis from live surgeries. The natural course of this disease is one of steady progression with eventual collapse of the femoral head, followed by secondary osteoarthritis in the hip joint. All samples showed a clear denaturation peak on the calorimetric curve. Cartilage obtained from necrotic femoral head required the lowest amount of energy for decomposition. The use differential scanning calorimetry as part of thermal analysis was a reliable method for differentiating.

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Abstract  

The glenohumeral joint is not a classical mass bearing joint, the treatment of primary osteoarthritis is conservative. In all other cases, when the arthritis is associated with unbalance of the soft tissues, the treatment solution of this pathology is arthroplasty. The purpose of this study was to examine the altered metabolism in human degenerated cartilage of the shoulder joint. With the rise of temperature an endothermic reaction was observed in all cases. The use differential scanning calorimetry as part of thermal analysis was a reliable method for differentiating normal hyaline cartilage from degenerated samples.

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Abstract  

The purpose of this study was to further characterize the altered metabolism spondylolisthesis that promotes disease progression. Degenerative human cartilage (intervertebral disc, facet joint and vertebral end-plate) was obtained during 15 posterior lumbar spine interbody fusion procedures performed at the University of Szeged. The thermal properties of samples were determined by differential scanning calorimetry (Mettler-Toledo DSC 821e). Greatest change in the enthalpy was observed in the intervertebral disc samples: −1600.78 J g−1. Denaturation caused by heating in the normal human hyaline cartilage needed −1493.31 J g−1 energy. Characterization of the altered metabolism that promotes disease progression should lead to future treatment options.

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Abstract  

During recent years, knowledge of rheumatoid arthritis has increased, and management of the disease has improved. A limited number of papers have been published before on the subject of thermal analysis of degenerative cartilage but rheumatoid arthritis (RA) has not been studied previously. A new protocol had to be established before the investigation. The purpose of this study was to further characterize the altered metabolism in human RA cartilage that promotes disease progression. Previously, these methods have not been used for this purpose. The use of thermal analysis could be an effective method for controlling the relationship between biomarkers and disease progression.

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Abstract  

Within the frame of a joint project, the accumulation of the uranium and transuranium (TRU) species on some structural materials used at Soviet made VVER-type pressurized water reactors (such as heat exchanger tube of steam generators and stainless steel canister material) has been studied. The experiments were carried out in a laboratory model system. During the sorption studies, boric acid coolants provided by the Paks Nuclear Power Plant (Paks NPP) were circulated for a period of 30 h. Solution and tube samples obtained in the course of above experiments were analyzed by independent methods (α- and γ-spectrometry, ICP-MS, SEM-EDX, voltammetry and XPS). The experimental results reveal that: (i) the surface excess of the TRU nuclides studied is extremely low (less than 1% of a monolayer coverage); (ii) the surface excess of uranium species measured on the SG tube surfaces is significantly higher, after 30 h sorption period (Γsample = 1.0 μg cm−2 U ≅ 3.7 × 10−9 mol cm−2 UO2) exceeds a monolayer coverage; (iii) the mechanistic features of the contamination processes (specific or non-specific adsorption, deposition of colloidal and/or disperse particles) depend decisively upon the nature of the studied radionuclides and the chemical structure and composition of the oxide layer formed on stainless steel surfaces.

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