Optical detection of paramagnetic centres in activated oxyfluoride glass-ceramics

Electron paramagnetic resonance (EPR), magnetic circular dichroism (MCD) and EPR detected via MCD (MCD-EPR) investigations have been performed on rare-earth activated oxyfluoride glasses and glass-ceramics. Er3+, Gd3+, and Mn2+ activators in oxyfluoride glass-ceramics show paramagnetic MCD behaviour and the MCD-EPR has been detected. The results of the MCD-EPR measurements for the Er-doped oxyfluoride glass-ceramics showed that Er3+ ions in the CaF2 crystallites in these ceramics embed only in the cubic symmetry environment, similarly to the previous observations of cubic Gd3+ centres in the glass-ceramics containing CaF2. Finally, the correlation of optics and paramagnetic centres is discussed for Mn-doped YAlO3 ceramics.Latvian-Ukrainian Joint Research Project (No LV-UA/2016/1 in Latvia and No M/78-2016 in Ukraine); Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART

Luminescence Properties and Decay Kinetics of Mn 2+ and Eu 3+ Co-Dopant Ions in MgGa 2 O 4 Ceramics

A. Luchechko gratefully acknowledges a grant from the Institute of Physics PAS for a research visit to the institute, while A.I. Popov has been supported by project LZP-2018/1-0214 from the Latvian Council of Science.The MgGa 2 O 4 ceramics co-doped with Mn 2+ and Eu 3+ ions were synthesized via a higherature solid-state reaction technique. The samples with various Eu 3+ concentrations were characterised using high-resolution photoluminescence (PL) spectroscopy. The PL spectra show weak matrix emission in a blue spectral region with dominant excitation band around 380 nm. Manganese ions are highly excited deeply in UV region and exhibit emission band peaked at 502 nm. The Eu 3+ ions show characteristic f-f excitation and emission lines. The energy transfer between host defects and activator ions was observed. Luminescence decay curves of Mn 2+ and Eu 3+ emission showed complex kinetics with both Eu 3+ -ion concentration and excitation wavelength changes.Latvian Council of Science LZP-2018/1-0214; Latvian–Ukrainian Joint Research Project LV-UA/2016/1,M/.8-2018; project DB/RIDER0117U004443; Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART

Thermally induced fading of Mn-doped YAP nanoceramic

We study pomax games, a family of combinatorial games which are always integer-valued. Specifically, we study games played on Young diagrams and Boolean lattices. We find a linear algorithm for computing the values of pomax games played on Young diagrams with only two rows. Some of the statements involved in this proof hold also for games on general Young diagrams. For pomax games on Boolean lattices, we introduce the concept of upper and lower games and use that as a tool to study the distribution of possible game values. We prove that games that equal any sufficiently small even integer can always be found, and that the density of distinct game values converges when the game size tends to infinity. Based on computational evidence, we conjecture that if the upper and lower games of some game are identical, then the value of that game is the sum of the upper and lower game.Vi studerar pomaxspel, en familj av heltalsvärda kombinatoriska spel. Mer specifikt studerar vi dessa spel då de spelas på Youngdiagram och Boolska lattis. Vi hittar en linjär algoritm för att beräkna värdet av pomaxspel på Youngdiagram med som mest två rader. Vissa av de ingående resultaten håller även for spel på allmänna Youngdiagram. Gällande pomaxspel pa Boolska lattis introducerar vi koncepten övre och undre spel, och använder detta for att analysera fördelningen av möjliga spelvärden. Vi visar att det alltid finns spel av varje tillräckligt litet jämnt värde, och att densiteten av distinkta spelvärden konvergerar då spelstorleken går mot oändligheten. Baserat på beräkningar förmodar vi att om det övre och undre spelet hörande till något spel ar identiska, så är detta spel lika med summan av det övre och undre spelet

snoRNA box C/D levels in leukemia cells in chromosomal abnormalities after irradiation

The study objective. This paper reviews the express of C/D box snoRNAs (small nucleolar RNAs) and possibility of their use as biomarkers of radioresistance in chromosomal abnormalities. Material and Methods. The study compared the values of log2FC express of snoRNA C/Dbox in radiosensitive (HL-60) and radioresistant (K562) cell lines with different levels of chromosomal abnormalities. The cells were irradiated with X-ray radiation once at a dose of 4 Gy. The expression of snoRNA C/D was evaluated 1, 4 and 24 hours after irradiation, using new generation sequencing (NGS) MiSeq. Results. Different log2FC values were obtained in HL-60 and K562 cell lines 1 hour, 4 and 24 hours after irradiation. Positive expression of C/D snoRNA prevails in HL-60 throughout the experiment. In K562, the predominance of positive values of C/D snoRNA expression was observed 4 hours after irradiation, and negative values of log2FC were observed 24 hours later. the more anomalies there were in the chromosome, the greater the difference in expression we observed. at the same time, the number of C/D snoRNA changed maximally 24 hours after irradiation in the studied cell lines. We noted a greater number of C/D snoRNAs in the HL-60 cell line, and only 3 expressed C/D snoRNAs in the 15th marker chromosome in K562 out of 16 in HL-60 in the same chromosome. Conclusion. Our study showed a low informative value of using C/D snoRNAs family as markers of radiosensitivity in the presence of chromosomal abnormalities in cancer cells