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Gödöllő, Hungary

Gemesi Z.,St Istvan University | Downing J.A.,Iowa State University | Cruse R.M.,Iowa State University | Anderson P.F.,Iowa State University
Journal of Environmental Quality | Year: 2011

We evaluated the relationships between landscape characteristics and lake water quality in receiving waters by regressing four water quality responses on landscape variables that were measured for whole watersheds and three different buffer distances (30, 60, and 120 m). Classical percolation theory was used to conceptualize nutrient pathways and to explain nonlinear responses. The response variables were total nitrogen (TN), total phosphorus (TP), chlorophyll-a (Chl-a), and Secchi transparency (SD). Landscape data were obtained from satellite image-derived maps of 130 watersheds in Iowa using geographic information systems software. We developed regression models with a stepwise protocol selecting the optimal number of significant explanatory variables. Configuration variables such as contagion, the cohesion of cropland and urban land, and the aggregation index of forest were very important and more important than variables assessing landscape composition (e.g., percentage farmland). Whole watershed models predicted between 15 and 67% of the variability in TN, TP, Chl-a, and SD. Proximity-explicit data offered only slightly improved statistical power over land cover data derived from the entire watershed for variables TN, Chl-a, and SD, but not for TP. Copyright © 2011 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved. Source

Kovacs A.,QS Biodiesel Ltd | Czinkota I.,St Istvan University | Toth J.,QS Biodiesel Ltd
JAOCS, Journal of the American Oil Chemists' Society | Year: 2012

The acidity of low and high free fatty acid containing feedstock varieties and biodiesel production intermediary products were tested using a variety of standard methods by the use of manual and automatic titration apparatus. The objective was to select the optimal test method for intermediary products in biodiesel processing and to optimize the selected technique by reducing the extent of bias.We found that there are two major reasons for variations in electrode potential readings. Colloid chemistry has an impact on the initial phase of titration by breakage and reformulation of the partially disperse system. Electric and magnetic fields in the titration beaker were the main reasons for sensitive fluctuations in electrode potentials in the potential range of interest for acid number readings. Refluxing the analyte with the diluting solvent proved to be an efficient technique to offset the influence of colloid processes. Addition of a filter electrolyte to the titration solvent allowed the filter fluctuations to be related to changes in uniformity of electric and magnetic fields in the titration beaker. Addition of filter electrolyte improved signal reliability than shading the external noises by wrapping the titration beaker in aluminium foil. Mathematical interpretation of potential readings revealed the extent of improvement in electrode potential fluctuation by the techniques employed. Both the aqueous and non-aqueous titration are suitable for accurate testing the acid number of biodiesel feedstock and intermediary products. © AOCS 2011. Source

Petroczki K.,St Istvan University | Fenyvesi L.,Hungarian Institute of Agricultural Engineering
Computers and Electronics in Agriculture | Year: 2014

Since the construction of a static and dynamic compressive testing instrument for examining biological materials, particularly fruits and tubercular roots, the need has arisen for the construction of a computer-controlled instrument that can bridge the gap between static and dynamic investigations in this field. The main utilisation possibilities of this instrument are demonstrated some measurement results with apple. The recently developed, easy-to-use instrument presented herein is suitable for serial measurements. In its present implementation, this instrument is capable of performing compressive testing with loading sticks of typical size with constant, linear slope and cosine force-time functions in single or cyclic mode. The force is generated by a PC-controlled servo system, and the deformation is measured by a laser sensor. The excitation force is 0-15. N within 1% FS accuracy in 0-300. Hz frequency range. Deformation measuring range is 10. mm with 12. μm resolution. The system contains a PC-based data logger. © 2013 Elsevier B.V. Source

Cent J.,Jagiellonian University | Mertens C.,St Istvan University | NiedziaLkowski K.,Polish Academy of Sciences | NiedziaLkowski K.,University of Leeds
Environmental Conservation | Year: 2013

The ecological network of Natura 2000, an European Union (EU) initiative to halt biodiversity loss across Europe, has dominated biodiversity governance in the new EU member states in recent years, as implementation was a condition of accession. Non-governmental organizations (NGOs) have generally assisted Natura 2000 implementation. In two Central and Eastern European countries (Poland and Hungary), NGOs became involved in different ways; this paper seeks to analyse and explain these national differences by researching the theoretical background of policy networks and advocacy coalitions in both countries. In Hungary, NGOs worked closely with governmental authorities and contributed significantly to site selection. In Poland, NGOs initially opposed government plans, but later moved toward close cooperation with public institutions; this resulted in a significant expansion in the area and number of designated Natura 2000 sites. In both countries, NGO influence increased during the Natura 2000 process owing to the establishment of multi-level policy networks with the European Commission and public institutions, based on resource dependencies and shared beliefs. In post-socialist countries, the progression from government-monopolized biodiversity conservation implies a growing importance and contribution of NGOs, and their ability to use resources appropriately in the new governance contexts. © Foundation for Environmental Conservation 2013. Source

Szasz A.,St Istvan University | Szasz A.,Chiba University
2014 31th URSI General Assembly and Scientific Symposium, URSI GASS 2014 | Year: 2014

Hyperthermia was the very first oncotherapy in human medicine. Despite its long history it has not achieved any breakthrough in clinical practices. The discovery of electromagnetism gave new hopes a century ago, however some controversies blocked its wide application. Oncothermia is a renewal, applying the synergy of the bioelectromagnetism with fractal physiology. Its basic approach makes selective energy absorption targeting the membrane rafts of the malignant cells. In this meaning this is a nanotechnology, treating the naturally present nano-particles (rafts) in 5 nm-range. The goal of the treatment is to induce apoptosis and drive the lost complex structure by possible re-synchronization of the autonomic malignant cells. The treatment tries avoid the constrains which induce unhelpful physiological reactions like the increase of the blood-flow which supports the tumor by nutrients and promotes metastatic processes. Oncothermia re-establishes the lost complexity of the malignant processes. © 2014 IEEE. Source

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