The highest peak on Rila Mountain is Moussala (2925 m a. s. l.). Its climate conditions depend on the geographic location, peculiarities of relief, and atmospheric circulation, and a specific microclimate is formed. In alpine regions, conditions become extremely variable with the increase in altitude. Plants that are growing in alpine conditions are exposed to the combined impact of environmental factors such as altitude, prolonged UV irradiation, low temperature, etc. This study aims to compare and assess whether the pigment content of wild-growing species at Moussala peak changes in the two following years. As plant material was used following species: Saxifraga cymosa Waldst & Kit (Saxifragaceae), Anthemis carpatica Waldst. & Kit. ex Willd. (Asteraceae), Geum repens (Rosaceae), Doronicum columnae Ten.(Asteraceae), Achillea clusiana L. (Asteraceae), Allium sibiricum L. (Liliaceae) and Festuca valida (R.Uechtr.) Pénzes (Poaceae). Plants were collected from Moussala Peak in July-August, in two successive growing seasons of 2020 and 2021. Data for the average daily value of “Erythemal UV irradiance” response (UVE) for the experimental site at Rila Mountain (2925 m a. s. l.) were measured with a UV sensor. Average daily values for July and August are calculated. Photosynthetic pigment content was applied as an endpoint. It was obtained that genotype response varies depending on the environmental conditions of the studied year. Data for UV irradiation at Moussala peak for a period of two following years 2020-2021 show insignificant change. Radiation conditions at Moussala peak show that both years differed in UVE response, but this small change of UV irradiation for one year is probably insignificant. The levels of total chlorophylls, chl. a, chl. b and total carotenoids for most of the studied alpine plants measured for 2021 were insignificantly higher in comparison with those measured for 2020. Only for S. cymosa were evaluated significantly higher pigment levels in 2021 than those in 2020. The chlorophyll a/b ratio was stable for all studied wild species growing at this altitude. The chlorophyll a/b ratio also varies depending on the studied genotype and different radiation conditions of the years studied. Our preliminary data indicate a change in pigment content depending on the different environmental conditions in the respective years and alpine plants examined. Data for radiation conditions at Moussala peak show that both years differed in UVE response, but this small change of UV irradiation for one year is probably insignificant. Changes in pigment content in some of the studied alpine genotypes propose different adaptive strategies to overcome the environmental stress at this altitude. Because alpine conditions at Moussala peak are related to the various impacts of extreme environmental factors on the pigment content of plants, further studies are needed to understand the mechanisms of interaction of factors and plant response in the long-term aspect of time.

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Tsveta Angelova, Nikolai Tyutyundzhiev, Christo Angelov, Svetla Gateva, Gabriele Jovtchev, "Assessment of pigment content on wild growing plants in moussala peak", RAD Conf. Proc, vol. 6, 2022, pp. 1-7, http://doi.org/10.21175/RadProc.2022.01

Radionuclides of interest in nuclear medicine are generally produced in cyclotrons or nuclear reactors, with associated issues such as highly enriched target costs and undesired contaminants. The ISOLPHARM project (ISOL technique for radioPHARMaceuticals) explores the feasibility of producing extremely high specific activity β-emitting radionuclides as radiopharmaceutical precursors. This technique is expected to produce radiopharmaceuticals very hardly obtained in standard production facilities. Radioactive isotopes will be obtained from nuclear reactions induced by accelerating 40 MeV protons in a cyclotron to collide on a UCx target. By means of: high working temperatures and high vacuum conditions, the migration of the radioactive elements towards an ion source, a potential difference up to 40 kV, and a mass separation device, an isobaric beam of desired radionuclides will be produced and implanted on a deposition target. The availability of innovative isotopes can potentially open a new generation of radiopharmaceuticals, based on nuclides never studied so far. Among these, a very promising isotope could be Ag-111, a β- emitter with a half-life (7.45 d), an average β- energy of 360 keV, a tissue penetration of around 1 mm, and a low percentage of γ-emission. The proof of principle studies on Ag-111 production and radiolabeling are currently under investigation in the ISOLPHARM_EIRA project, where both its production and possible application as a radiopharmaceutical precursor will be evaluated in its computational/physics, radiochemistry, and radiobiology tasks. Currently, innovative macromolecules meeting the specific requirements for the chelation and targeted delivery of Ag-111 are being developed, which will be further tested in vitro on 2D and 3D models, as well as in vivo for their pharmacokinetics and therapeutic potential onto xenograft models.

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E. Vettorato, L. Morselli, M. Ballan, A. Arzenton, O. S. Khwairakpam, M. Verona, D. Scarpa, S. Corradetti, P. Caliceti, V. Di Marco, F. Mastrotto, G. Marzaro, N. Realdon, A. Zenoni, A. Donzella, M. Lunardon, L. Zangrando, M. Asti, G. Russo, E. Mariotti, D. Maniglio, A. Andrighetto, "A new production method of high specific activity radionuclides towards innovative radiopharmaceuticals: the isolpharm project", RAD Conf. Proc, vol. 6, 2022, pp. 8-14, http://doi.org/10.21175/RadProc.2022.02

In this paper, we discuss the method of setting the optimal working voltage on the photomultipliers of detectors containing thin plastic scintillation materials. These plastic scintillators may additionally include a zinc sulfide ZnS(Ag) layer for the separation of alpha and beta particles. The ionizing radiation on the thin plastic scintillators is not fully absorbed and therefore it is not possible to determine the position of the Compton edge. This is very important for energy calibration. We have proposed a simple method for this purpose and carried out all tests with the newly developed smart frisking probe. The results are presented.

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Aleš Jančář, Jiří Čulen, Filip Mravec, Zdeněk Matěj, "Method of setting optimal operating voltage for radiation detectors containing thin plastic scintillators", RAD Conf. Proc, vol. 6, 2022, pp. 15–20, http://doi.org/10.21175/RadProc.2022.03

Most of the detectors used for radon measurements rely on registering the alpha-rays coming from the ²²²Rn decay itself and those from its daughters ²¹⁸Po and ²¹⁴Po, as well. Although active alpha-detectors have very low background and good efficiency, they are relatively expensive and are not well suited for field work due to their sensitivity to the ambient air humidity. In this work, an alternative possibility for in situ systematic measurements (monitoring) of radon concentration is investigated. It is suggested to use simple and wide spread detectors - Geiger-Mueller (GM) counters which are sensitive to beta/gamma radiation of ²²²Rn daughters ²¹⁴Pb and ²¹⁴Bi. Long term measurements of the radiation background in uninhabited dwelling rooms were performed using simultaneously a classical radon alpha-particles detector (based on an ion chamber) and a beta/gamma detector (GM counter); the basic meteorological parameters at the site were also monitored. A very high correlation between the response of both detectors was found (r²~0.9) which indicates that the radon monitoring can be successfully performed by means of cheap and moisture resistant GM counters. The drawbacks and the limitations of this method are also discussed.

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Atanas Terziyski, Ludmil Tsankov, Stoyan Tenev, Vedrin Jeliazkov "Feasibility of in situ radon monitoring using common gm counters", RAD Conf. Proc, vol. 6, 2022, pp. 21–25, http://doi.org/10.21175/RadProc.2022.04