EXPERIMENTAL TECHNIQUE TO MEASURE THORON GENERATION RATE OF BUILDING MATERIAL SAMPLES USING RAD7 DETECTOR

Thoron (220Rn) is the second most abundant radon isotope in our living environment. In some dwellings it is present in significant amount which calls for its identification and remediation. Indoor thoron originates mainly from building materials. In this work we have developed and tested an experimental technique to measure thoron generation rate in building material samples using RAD7 radon-thoron detector. The mathematical model of the measurement technique provides the thoron concentration response of RAD7 as a function of the sample thickness. For experimental validation of the technique an adobe building material sample was selected for measuring the thoron concentration at nineteen different sample thicknesses. Fitting the parameters of the model to the measurement results, both the generation rate and the diffusion length of thoron was estimated. We have also determined the optimal sample thickness for estimating the thoron generation rate from a single measurement

Fission products from the damaged Fukushima reactor observed in Hungary

Fission products, especially 131I, 134Cs and 137Cs from the damaged Fukushima Dai-ichi Nuclear Power Plant have been detected many places worldwide shortly after the accident caused by natural disaster. To observe the spatial and temporal variation of these isotopes in Hungary, aerosol samples have been collected at five locations from late March to early May 2011: Institute of Nuclear Research, Hungarian Academy of Sciences (ATOMKI, Debrecen, East-Hungary), Paks NPP (Paks, South-Central-Hungary) as well as at the vicinity of Aggtelek (Northeast-Hungary), Tapolca (West-Hungary) and Bátaapáti (Southwest-Hungary) settlements. In addition to the aerosol samples, dry/wet fallout samples have been collected at ATOMKI, and airborne elemental iodine and organic iodide samples have been collected at Paks NPP. The peak in the activity concentration of airborne 131I has been observed around 30 March (1-3 mBq/m3 both in aerosol samples and gaseous iodine traps) with slow decline afterwards. Aerosol samples of several hundred cubic meters of air showed 134Cs and 137Cs in detectable amounts along with 131I. The decay corrected inventory of 131I fallout at ATOMKI was 2.1±0.1 Bq/m2 at maximum in the observation period. Dose-rate contribution calculations show that the radiological impact of this event at Hungarian locations has been of no considerable concern

The Impact of Obesity on the Cardiovascular System

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Enhanced growth of tellurium nanowires under conditions of macromolecular crowding

The time-evolution of the mean excitonic wavelength demonstrating the enhanced ripening and growth rates of tellurium nanowires at increasing concentrations of the PVP crowder.</p

In vivo assessment of tumor targeting potential of 68Ga-labelled randomly methylated beta-cyclodextrin (RAMEB) and 2-hydroxypropyl-β-cyclodextrin (HPβCD) using positron emission tomography

Cyclodextrin derivates (CyDs) can form complexes with cyclooxygenase-2 induced tumor promoting prostaglandin E2 (PGE2). Based on our previous observations, 68Ga-labelled CyDs may represent promising radiopharmaceuticals in the positron emission tomography (PET) diagnostics of PGE2 positive tumors. We aimed at evaluating the tumor-targeting potential of 68Ga-NODAGA conjugated randomly methylated beta-cyclodextrin (68Ga-NODAGA-RAMEB) and 2-hydroxypropyl-β-cyclodextrin (68Ga-NODAGA-HPβCD) using in vivo PET imaging with experimental tumor models. Tumor radiopharmaceutical uptake was assessed applying PET and gamma counter in vivo and ex vivo respectively, following the administration of 18FDG, 68Ga-NODAGA-RAMEB or 68Ga-NODAGA-HPβCD via the lateral tail vein to the subsequent tumor-bearing animals: HT1080, A20, PancTu-1, BxPC3, B16-F10, Ne/De and He/De. All investigated tumors were identifiable with both 68Ga-labelled CyDs; however, in vivo results, in correlation with the ex vivo data, revealed that the PGE2 positive BxPC3, A20, Ne/De and He/De tumors presented the highest accumulation. In case of HT1080, A20, B16-F10 tumors significant differences were encountered between the accumulations of both 68Ga-labelled radiopharmaceuticals of the same tumor. Subcutaneously and the orthotopically transplanted Ne/De tumors differed significantly (p ≤ 0.01) regarding tracer uptake. 68Ga-labelled CyDs may open a novel field in the PET diagnostics of PGE2 positive primary tumors and metastases