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Michael F. L'Annunziata: Handbook of Radioactivity Analysis, Second Edition, Academic Press

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In this paper we analyse the most important mechanisms of the Hungarian economy with the help of a medium-sized quarterly macroeconomic model developed jointly by the Economic Policy Department of the Ministry of Finance and the Institute of Economics of the Hungarian Academy of Sciences. After introducing the building blocks of the model we investigate, within a scenario analysis, the effects of the main factors behind the macroeconomic and budgetary processes. The sources of uncertainty — defined in a broad sense — are categorised into three groups: changes in the external environment (e.g. an adverse external business cycle shock or an exchange rate shock), uncertainties in the estimated behaviour of economic agents (e.g. in the speed of wage adjustment or in the extent of consumption smoothing), and economic policy decisions (such as the increase of public sector wages). Taking into account the complex relationships between the various areas of the economy, we analyse the short and medium term consequences of such shocks and uncertainties on GDP, its components, the general government deficit and the public debt. We also show that the macroeconomic consequences of the uncertainties are not independent of each other: for instance, the effects of an exchange rate shock are influenced by the speed of wage adjustment.

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Abstract  

The retention of the radioactive noble gases takes place on the charcoal adsorber by dynamic adsorption, meanwhile their radioactivity decrease according to their half-life-times. For the optimal operation of the adsorber units the on-line control and analysis of the retention properties would be required. Therefore a procedure has been developed for the determination of the retention times and the dynamic adsorption coefficients for the specific noble gas isotopes. The method is based on the continuous analysis of the in- and out-flow of the adsorber system by -ray spectroscopy using semiconductor detectors. After the successful laboratory test, the procedure was installed and the retention properties of a charcoal based radioactive gas adsorber system were determined. For the evaluation of the data, a theoretical model was developed, which was used for the calculation of the dynamic retention coefficients of the noble gas isotopes.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: R. Chobola, R. Chobola, P. Mell, P. Mell, L. Daróczi, L. Daróczi, A. Vincze, and A. Vincze

Summary  

A relatively simple chemical separation procedure has been developed for the simultaneous determination of89Sr and 9 0Sractivities in water samples and on aerosol-filters of the Nuclear Power Plant (NPP) Paks origin. The procedure combines the cation-exchange chromatographic (Dowex 50 WX 8 resin) and solid phase extraction (EIChroM Sr.SpecÔ, DC18C6 crown ether) steps. The beta-radiation of radionuclides can be measured directly after the chemical separation by LSC. The activities of89Sr,90Sr and90Y are calculated from an over determined set of equations using a method of constrained optimization technique. The equations are based on LSC measurements performed in three counting windows plus the90Sr-90Y decay law. The chemical yield of strontium is determined by ICP-AES. The lowest limits of detectable activity, for the measurement time of 600 minutes, are 30 mBq/sample and 18 mBq/sample for89Sr and90Sr, respectively.

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A comparative analysis of human and experimental animal (canine) tissues was performed to characterize and describe cellular and histological responses during the processes of newly forming intravascular tissues after stent implantation. Routine histological and immunohistochemical evaluation of 20 human samples and 9 samples from animal models were used one day, one week and one month after the stent implantation. After one day of implantation, there was no difference between the human and canine peripheral arteries, suggesting a similar cellular and histological response in the early phase. In contrast, after one week of implantation, during the proliferative phase the repairing human tissue showed less intensive production of inflammatory cells and more intensive increase in number of vascular cells than did the canine model. In addition, cellular changes normally restituted by the end of one month in canine peripheral arteries, but vascular cells persisted in human atherosclerotic arteries. In conclusion, results of this study suggest differences in both phases of vascular repair in the post-stented period, because both proliferative and regressive phases showed histological differences in canine and human samples. In canine, the restitution of vascular wall was completed by the end of first month but persistent vascular cell proliferation was visible in the human peripheral arteries. It can be suggested that delayed cellular response might indicate restenosis but also can be considered considered as a progression of the original arterial disease.

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Automated behavioural observations are routinely used in many fields of biology, including ethology, behavioural ecology and physiology. When preferences for certain resources are investigated, the focus is often on simple response variables, such as duration and frequency of visits to choice chambers. Here we present an automated motion detector system that use passive infrared sensors to eliminate many drawbacks of currently existing methods. Signals from the sensors are processed by a custom-built interface, and after unnecessary data is filtered by a computer software, the total time and frequency of the subject’s visits to each of the choice chambers are calculated. We validate the detector system by monitoring (using the system) and in the same time video recording mating preferences of zebra finches in a four-way choice apparatus. Manual scoring of the video recordings showed very high consistency with data from the detector system both for time and for frequency of visits. Furthermore, the validation revealed that if we used micro-switches or light barriers, the most commonly applied automatic detection techniques, this would have resulted in approximately 22% less information compared to our lossless system. The system provides a low-cost alternative for monitoring animal movements, and we discuss its further applicability.

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Acta Linguistica Academica
Authors: Tommi A. Pirinen, Francis M. Tyers, Eszter Simon, and Veronika Vincze
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Abstract  

In this paper, the development of a new-type of resin is presented, which contains selective complexing and scintillating molecules in a chemically bonded form. The resin material is produced via radiation polymerization of a solution of 2-(4-allyloxy-phenyl)-5-phenyl oxazole, 5-(allyloxy-phenyl)-2-[4-(5-phenyl-oxazole-2-il)-phenyl] oxazole, diethylene glycol dimethacrylate (DEGMA), styrene and the allyl derivative of a 18C6 crown ether-dicarbolic acid complexing agent. The product is a macroporous polymer matrix that shows fluorescent properties and ion binding capacity excellent for radioanalytical purposes.

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In earlier works we have found that in the mammalian pineal organ, a part of autonomic nerves - generally thought to mediate light information from the retina - form vasomotor endings on smooth muscle cells of vessels. We supposed that they serve the vascular support for circadian and circannual periodic changes in the metabolic activity of the pineal tissue. In the present work, we investigated whether peripheral nerves present in the photoreceptive pineal organs of submammalians form similar terminals on microvessels. In the cyclostome, fish, amphibian, reptile and bird species investigated, autonomic nerves accompany vessels entering the arachnoidal capsule and interfollicular meningeal septa of the pineal organ. The autonomic nerves do not enter the pineal tissue proper but remain in the perivasal meningeal septa isolated by basal lamina. They are composed of unmyelinated and myelinated fibers and form terminals around arterioles, veins and capillaries. The terminals contain synaptic and granular vesicles. Comparing various vertebrates, more perivasal terminals were found in reptiles and birds than in the cyclostome, fish and amphibian pineal organs. Earlier, autonomic nerves of the pineal organs were predominantly investigated in connection with the innervation of pineal tissue. The perivasal terminals found in various submammalians show that a part of the pineal autonomic fibers are vasomotoric in nature, but the vasosensor function of some fibers cannot be excluded. We suppose that the vasomotor regulation of the pineal microvessels in the photosensory submamalian pineal - like in mammals - may serve the vascular support for circadian and circannual periodic changes in the metabolic activity of the pineal tissue. The higher number of perivasal terminals in reptiles and birds may correspond to the higher metabolic activity of the tissues in more differentiated species.

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