Kinetic parameters of the uranium luminescence in Lif crystals

The results of researches with nanosecond time resolution of kinetic characteristics of luminescence buildup and decay in crystals LiF(U)-O at 300 K under action of both laser pulse with energy 3,68 eV and electron pulse with energy 300 keV have been presented. Influence of excite method on kinetic characteristics of uranium luminescence buildup and influence of uranium on kinetic characteristics of oxygen luminescence in crystal were establishe

Thermal stability of color centers in LiF crystals: dependence on radiation type and dose

Accumulation of radiation defects at irradiation is the complex result of consecutive and mutually independent events: formation of primary pair, spatial separation of its components and their transformation into stable ones under experimental conditions [1]..

Thermal stability of color centers in LiF crystals: dependence on radiation type and dose

Accumulation of radiation defects at irradiation is the complex result of consecutive and mutually independent events: formation of primary pair, spatial separation of its components and their transformation into stable ones under experimental conditions [1]..

Nanodefects in Highly Imperfect Optical Crystals

Experiments were carried out within the framework of the development program of the National Research Tomsk Polytechnic University in the project of the leading universities of theworld 5–100 (Project № VIU-OM-205/2018)

Tungsten Activated Ceramics Based on Metal Fluorides

This work is aimed at establishing the possibility of introducing W ions into ceramics based on alkaline earth metal fluorides by the radiation synthesis method, which differs significantly in the totality of processes from the currently used thermal methods

Structure and Dynamics of Thermosensitive pDNA Polyplexes Studied by Time-Resolved Fluorescence Spectroscopy

Combining multiple stimuli-responsive functionalities into the polymer design is an attractive approach to improve nucleic acid delivery. However, more in-depth fundamental understanding how the multiple functionalities in the polymer structures are influencing polyplex formation and stability is essential for the rational development of such delivery systems. Therefore, in this study the structure and dynamics of thermosensitive polyplexes were investigated by tracking the behavior of labeled plasmid DNA (pDNA) and polymer with time-resolved fluorescence spectroscopy using fluorescence resonance energy transfer (FRET). The successful synthesis of a heterofunctional poly(ethylene glycol) (PEG) macroinitiator containing both an atom transfer radical polymerization (ATRP) and reversible addition-fragmentation chain-transfer (RAFT) initiator is reported. The use of this novel PEG macroinitiator allows for the controlled polymerization of cationic and thermosensitive linear triblock copolymers and labeling of the chain-end with a fluorescent dye by maleimide-thiol chemistry. The polymers consisted of a thermosensitive poly(N-isopropylacrylamide) (PNIPAM, N), hydrophilic PEG (P), and cationic poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA, D) block, further referred to as NPD. Polymer block D chain-ends were labeled with Cy3, while pDNA was labeled with FITC. The thermosensitive NPD polymers were used to prepare pDNA polyplexes, and the effect of the N/P charge ratio, temperature, and composition of the triblock copolymer on the polyplex properties were investigated, taking nonthermosensitive PD polymers as the control. FRET was observed both at 4 and 37 degrees C, indicating that the introduction of the thermosensitive PNIPAM block did not compromise the polyplex structure even above the polymer's cloud point. Furthermore, FRET results showed that the NPD- and PD-based polyplexes have a less dense core compared to polyplexes based on cationic homopolymers (such as PEI) as reported before. The polyplexes showed to have a dynamic character meaning that the polymer chains can exchange between the polyplex core and shell. Mobility of the polymers allow their uniform redistribution within the polyplex and this feature has been reported to be favorable in the context of pDNA release and subsequent improved transfection efficiency, compared to nondynamic formulations.Peer reviewe

Structural and luminescent characteristics of YAG phosphors synthesized in the radiation field

YAG:Ce, YAGG:Ce ceramics were obtained by sintering the oxide powders in the radiation field. The results of investigations of the structure, composition and luminescence of ceramics are presented. The luminescence characteristics of powders exactly correspond to the phosphors luminescence used in practice obtained by solid-state synthesis methods. It has been established that in the used radiation exposure modes the main factor determining the efficiency of the synthesis is the ionization density

Comparative analysis of anxiety-depressive spectrum disorders in patients with rheumatic diseases

Research objective - comparative analysis of incidence and structure of anxiety-depressive spectrum disorders (ADD) in patients with various rheumatic diseases (RD). Materials and methods. 613 patients with RD were enrolled in the study: 180 with a reliable diagnosis of systemic lupus erythematosus (SLE), 128 with rheumatoid arthritis (RA), 110 with systemic sclerosis (SSc), 115 with Behcet's disease (BD), 80 with primary Sjögren's syndrome (pSS). Female prevailed in all groups (95% of patients with pSS, 88,2% - SSc, 87,2% - RA, 85,5% of SLE) except BD patients (70% male). The mean age was 42.3±1.54 years and was lower in patients with BD (33.3±0.98 years) and SLE (34.6±0.93 years) compared to patients with SSc (49.9±2.47 years), RA (47.4±0.99 years) and pSS (46.2±2.3 years). The mean RD duration was 130,0±8,65 months and was more at BD - 148,5±10,4 months, pSS - 141,6±8,92 months, RA - 138,4±10,1months, and less at SLE - 134,9±8,8 months and SSc - 87,0±5,04 months. The mean SLE activity index SLEDAI was 9,13±0,63 points (high), RA (DAS28) - 5,26±0,17 points (high), BD (BDCAF) - 3,79±0,2 points (moderate) and SSc by G. Valentini - 1,1±0,20 points (moderate). Glucocorticoids took 100% of patients with pSS, 91,1% - SLE, 90% - SSc, 87% - BD and 67,2% - RA patients; conventional disease modifying anti-rheumatic drugs (cDMARDs) took 90% of patients with SSc, 84% - BD, 79,6% - RA, 68% - pSS, 40,6% - SLE. Biologic DMARDs took 32% of patients with RA, 17,4% - BD, 7,3% - SSc and 7,2% - SLE. Mental disorders were diagnosed by psychiatrist as a result of screening by the hospital anxiety and depression scale (HADS) and in semi-structured interview in accordance with the ICD-10/ DSM-IV. The severity of depression was evaluated by Montgomery-Asberg Depression Rating Scale (MADRS) and anxiety - by Hamilton Anxiety Rating Scale (HAM-A). Projective psychological methods were used for cognitive impairment detection. Results. Screening of depressive disorders (HADS-D≥8) was positive in 180 (29,4%) patients with RD, including 74 (41%) patients with SLE, 38 (35%) - SSc, 29 (23%) - RA, 23 (20%) - BD and 16 (20%) - pSS; anxiety disorders (HADS-A≥8) - in 272 (44,4%) patients, including 66 (52%) patients with RA, 40 (50%) - pSS, 77 (43%) - SLE, 45 (41%) - SSc and 44 (38%) - BD. In accordance with the ICD-10/ DSM-IV depressive disorders have been identified in 389 (63%) patients, including 94 (73%) patients with RA, 71 (64,5%) - SSc, 69 (60%) - BD, 90 (50%) - SLE and 39 (49%) - pSS; anxiety disorders - in 377 (61,5%) patients, including 20 (25%) patients with pSS, 44 (24,5%) - SLE, 29 (23%) - RA, 20 (17%) - BD and 7 (6,4%) - SSc. Conclusion. Anxiety-depressive spectrum disorders are typical for most patients with RA, SLE, SSc, pSS and BD. ADDs diagnosis in RD patients with the use of the HADS did not reveal a significant proportion. To obtain objective data on the frequency and structure of ADDs, psychopathological and clinical psychological diagnosis is necessary

Structural and luminescent characteristics of YAG phosphors synthesized in the radiation field

YAG:Ce, YAGG:Ce ceramics were obtained by sintering the oxide powders in the radiation field. The results of investigations of the structure, composition and luminescence of ceramics are presented. The luminescence characteristics of powders exactly correspond to the phosphors luminescence used in practice obtained by solid-state synthesis methods. It has been established that in the used radiation exposure modes the main factor determining the efficiency of the synthesis is the ionization density