We report on a novel 5µm thick vitrified film prepared from the amorphous powder of the mesogenic terbium(III) β-diketonate complex and supported on a quartz plate through melt-processing technique. ...For the first time a 16-fold increase in the mean photoluminescence intensity of Tb3+ ions in the film was observed after a prolonged irradiation of the film by 337nm pulsed nitrogen laser in air at room temperature. The analysis of optical spectroscopy data has shown that the main reason responsible for the observed phenomenon was a change in the inner coordination spheres of Tb3+ ions. It resulted in an increase in energy gaps between the emitting 5D4 level of the Tb3+ ions and triplet states of ligands. In this way the efficiency of the energy back transfer from the 5D4 level of the Tb3+ ions to the triplet state of the ligands was decreased and the mean photoluminescence intensity of the Tb3+ ions in the film was enhanced.
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Lanthanide β‐diketonate complexes are found to exhibit a smectic A and a nematic phase over a broad temperature range. Polarized luminescence is observed for the europium(III) complex dissolved in ...the nematic liquid‐crystal mixture E7 and for the aligned vitrified mesophase.
A new film material capable of transforming UV radiation into visible light was obtained from a highly anisometric EuIII complex with organic ligands in a polymethylmethacrylate (PMMA) matrix and ...then structurally characterized. An important advantage of the synthesized complex is its good solubility in organic solvents such as dichloromethane, chloroform, THF, toluene, etc. The ligand environment (flexible alkyl and cyclohexyl substituents) of the EuIII complex was selected to prevent crystallization, to inhibit the formation of defects in the structure of films and to provide its uniform distribution in the polymer during polymerization. As a result we obtain an EuIII complex of the film with remarkable thermal behavior: the complex melts to isotropic liquid without decomposition, it supercools at ambient temperature and it forms a stable amorphous material at low (up to −30°C) temperatures. The films were prepared by two methods: bulk polymerization and spin coating. A comparison of the differences of luminescent and optical characteristics of micro‐ and nanosized PMMA films doped with the anisometric EuIII complex is given. Based on X‐ray powder diffraction and small‐angle scattering data, it has been supposed that the association of EuIII complex molecules occurs in the voids of the PMMA matrix and is accompanied by the formation of a nanocrystalline phase. For films obtained by spin coating, a deeper microphase separation is demonstrated than by bulk polymerization. The dimensional characteristics of the nano‐associates were determined and a correlation between the method of preparation and the type of distribution of the EuIII complex in the PMMA matrix is established.
A new film material capable of transforming UV radiation into visible light was obtained from a new EuIII anisometric complex with organic ligands in a polymethylmethacrylate (PMMA) matrix and structurally characterized. From X‐ray powder diffraction and small‐angle scattering data, it is supposed that molecules of the EuIII complex occur in the voids of the PMMA matrix and this is accompanied by the formation of a nanocrystalline phase.
Satellite DNA (satDNA) constitutes a substantial part of eukaryotic genomes. In the last decade, it has been shown that satDNA is not an inert part of the genome and its function extends beyond the ...nuclear membrane. However, the number of model plant species suitable for studying the novel horizons of satDNA functionality is low. Here, we explored the satellitome of the model "basal" plant,
(Hedwig, 1801) Bruch & Schimper, 1849 (moss), which has a number of advantages for deep functional and evolutionary research. Using a newly developed pyTanFinder pipeline (https://github.com/Kirovez/pyTanFinder) coupled with fluorescence
hybridization (FISH), we identified five high copy number tandem repeats (TRs) occupying a long DNA array in the moss genome. The nuclear organization study revealed that two TRs had distinct locations in the moss genome, concentrating in the heterochromatin and knob-rDNA like chromatin bodies. Further genomic, epigenetic and transcriptomic analysis showed that one TR, named PpNATR76, was located in the intergenic spacer (IGS) region and transcribed into long non-coding RNAs (lncRNAs). Several specific features of PpNATR76 lncRNAs make them very similar with the recently discovered human lncRNAs, raising a number of questions for future studies. This work provides new resources for functional studies of satellitome in plants using the model organism
, and describes a list of tandem repeats for further analysis.
Structural modifications following long-term UV irradiation with a pulsed nitrogen laser led to a decrease/increase in the luminescence intensities of vitrified films with the thickness of 8/20µm, ...respectively. The films were prepared from a terbium(III) β-diketonate complex. Optical spectroscopic studies revealed that these features are associated with different structures of the films. The 20µm film includes the aggregates hindering the non-radiative relaxation of the T1 states of ligands. Such a phenomenon is not observed in the 8µm film. A comparative analysis of the luminescent data indicates that the redistribution of the T1 energies of the ligands under UV modification is the predominant reason for the changes of the luminescent properties of the films.
•Tb(CPDK3-7)3phen was synthesized and two vitrified transparent films were prepared.•UV irradiation decreases/increases luminescence intensity of 8/20µm thick film•Only 20µm film includes aggregates hindering the non-radiative relaxation.•After UV irradiation T1 energies became mostly lower/ higher in the 8/20µm film.•Redistribution of T1 energies changes the luminescent properties of the films.
A novel temperature-sensitive luminescent material was fabricated from a powder of a mesogenic terbium(
iii
) β-diketonate complex, Tb(CPDK
3-7
)
3
phen (CPDK
3-7
= ...1-(4-(4-propylcyclohexyl)phenyl)decane-1,3-dione, phen = 1,10-phenanthroline) by a melt-processing technique. The material is a 20 μm thick vitrified film sandwiched between two quartz plates. The film effectively absorbs light in the wavelength range of 280-405 nm and exhibits a green narrow-band luminescence of Tb
3+
ions due to efficient ligand-to-metal energy transfer. The average luminescence decay time varies reversibly with temperature from 373 μs at 143 K to 33 μs at 253 K having the mean absolute sensitivity of −3.3 μs K
−1
. The simplicity in design, the high optical transmittance (around 90%) in the visible wavelength region of 450-800 nm, the insensitivity to atmospheric oxygen and the complete resistance to UV light provide technological and operational advantages of the proposed material. The findings demonstrated that the material is promising as a sensing element for luminescent thermometers suitable for long-term temperature monitoring in the range of 143-253 K.
A highly efficient sensing element based on a photostable vitrified film of the terbium(
iii
) β-diketonate complex for reusable luminescent thermometers suitable for long-term monitoring in the range of 143-253 K.
This article discusses the device for active-passive mechanotherapy of the ankle joint. The device is based on a controlled mobile platform on which the patient's foot is placed using special cuffs ...equipped with force meters, while the rotation angles of the platform are controlled by special sensors. Structurally the platform of the device is installed so that the rotation of the platform is always coincided with the center of the ankle joint, for which the parallel kinematics mechanism based on three linear electric drives is used. The control system of the device provides both active and passive movement of the platform. For realization of algorithm of controlling movement of mobile platform, the mathematical model is developed, it allows to establish connections between angular motions of mobile platform and linear drives of parallel mechanism. The algorithms for controlling the platform are considered.
Development of novel approaches for regulating the expression of angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) is becoming increasingly important within the ...context of the ongoing COVID-19 pandemic since these enzymes play a crucial role in cell infection. In this work we searched for putative ACE2 and TMPRSS2 expression regulation networks mediated by various miRNA isoforms (isomiR) across different human organs using publicly available paired miRNA/mRNA-sequencing data from The Cancer Genome Atlas (TCGA) project. As a result, we identified several miRNA families targeting ACE2 and TMPRSS2 genes in multiple tissues. In particular, we found that lysine-specific demethylase 5B (JARID1B), encoded by the KDM5B gene, can indirectly affect ACE2 / TMPRSS2 expression by repressing transcription of hsa-let-7e / hsa-mir-125a and hsa-mir-141 / hsa-miR-200 miRNA families which are targeting these genes.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract The default mode network (DMN) has been principally investigated using positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) and has received mixed support in ...electroencephalographic (EEG) studies. In particular, the existing evidence is too inconsistent to allow formulation of specific hypotheses linking DMN activity to traditional EEG frequency bands. In this study, we aimed to test whether blind decomposition methods are able to identify in EEG data spatial patterns resembling the DMN as it is described in PET and fMRI studies. Further we aimed to test a degree of task-relatedness of DMN patterns identified in the traditional EEG frequency bands. To answer these questions we collected data both in a resting state and during performance of two experimental tasks: an explicit judgment of facial affect and a social game task. Individual differences in amount of self-referential thoughts during the resting state were measured by a short self-report scale. Only alpha band spatial patterns simultaneously showed a considerable overlap with the DMN and high correlations with presumptive DMN function-related outcomes both in the resting state and during the social game task. Spontaneous self-referential thoughts were associated with enhanced alpha activity in the posterior DMN hub, whereas processing of DMN function-related external stimuli disrupted this activity and simultaneously caused partial alpha phase-locking to external events. This evidence implies that synchronization of internal mental processes, as opposed to the processing of external stimuli, might be the primary function of alpha oscillations which is bound to be related to activity of the DMN.
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