Theoretical model of donor-donor and donor-acceptor energy transfer on a nanosphere.

In this study, we introduce a novel advancement in the field of theoretical exploration. Specifically, we investigate the transfer and trapping of electronic excitations within a two-component disordered system confined to a finite volume. The implications of our research extend to energy transfer phenomena on spherical nanoparticles, characterized by randomly distributed donors and acceptors on their surface.

General model of nonradiative excitation energy migration on a spherical nanoparticle with attached chromophores.

Theory of multistep excitation energy migration within the set of chemically identical chromophores distributed on the surface of a spherical nanoparticle is presented. The Green function solution to the master equation is expanded as a diagrammatic series. Topological reduction of the series leads to the expression for emission anisotropy decay.

Correction to Nonradiative Energy Migration in Spherical Nanoparticles Theoretical Model and Monte Carlo Study.

[This corrects the article DOI: 10.1021/acs.jpcc.

Nonconventional 1,8-Diazafluoren-9-One Aggregates for Green Light Enhancement in Hybrid Biocompatible Media.

Organic aggregates currently play a prominent role, mainly for their unique optoelectronic properties in the aggregated state. Such properties can be related to the aggregates' structure and the molecular packing mode. In the literature, we have well-established models of H and J aggregates defined based on the molecular exciton model.

New Core-Shell Nanostructures for FRET Studies: Synthesis, Characterization, and Quantitative Analysis.

This work describes the synthesis and characterization of new core-shell material designed for Förster resonance energy transfer (FRET) studies. Synthesis, structural and optical properties of core-shell nanostructures with a large number of two kinds of fluorophores bound to the shell are presented. As fluorophores, strongly fluorescent rhodamine 101 and rhodamine 110 chloride were selected.

Predicting Performance of Lightweight Concrete with Granulated Expanded Glass and Ash Aggregate by Means of Using Artificial Neural Networks.

Lightweight concrete (LWC) is a group of cement composites of the defined physical, mechanical, and chemical performance. The methods of designing the composition of LWC with the assumed density and compressive strength are used most commonly. The purpose of using LWC is the reduction of the structure's weight, as well as the reduction of thermal conductivity index.

Wear and friction properties of experimental Ti-Si-Zr alloys for biomedical applications.

Titanium alloys are widely used in biomedical applications due to their higher biocompatibility in comparison to other metallic biomaterials. However, they commonly contain aluminum and vanadium, whose ions may be detrimental to the nervous system. Furthermore, they suffer from poor wear resistance, which limits their applications.

Förster resonance energy transfer and trapping in selected systems: analysis by Monte-Carlo simulation.

Monte-Carlo simulation method is described and applied as an efficient tool to analyze experimental data in the presence of energy transfer in selected systems, where the use of analytical approaches is limited or even impossible. Several numerical and physical problems accompanying Monte-Carlo simulation are addressed. It is shown that the Monte-Carlo simulation enables to obtain orientation factor in partly ordered systems and other important energy transfer parameters unavailable directly from experiments.

Long-distance FRET analysis: a Monte Carlo simulation study.

A new method for extending the utilizable range of Förster resonance energy transfer (FRET) is proposed and tested by the Monte Carlo technique. The obtained results indicate that the efficiency of FRET can be significantly enhanced at a given distance if the energy transfer takes place toward multiple acceptors that are closely located on a macromolecule instead of a single acceptor molecule as it is currently used in FRET analysis. On the other hand, reasonable FRET efficiency can be obtained at significantly longer distances than in the case of a single acceptor.

How often pulmonary embolism mimics acute coronary syndrome?

Background: The clinical picture of acute pulmonary embolism (APE) is often uncharacteristic and may mimic acute coronary syndrome (ACS) or lung diseases, leading to misdiagnosis. In 50% of patients, APE is accompanied by chest pain and in 30-50% of the patients markers of myocardial injury are elevated.

Aim: To perform a retrospective assessment of how often clinical manifestations and investigations (ECG findings and elevated markers of myocardial injury) in patients with APE may be suggestive of ACS.

Acute pulmonary embolism registry in the Małopolska region - clinical course.

Background: Acute pulmonary embolism (APE) is a life-threatening disease. Mortality in APE still remains very high in spite of progress in diagnostic tools. Mortality rate is about 30% in patients with unrecognised APE.

Electronic excitation energy migration in partly ordered polymeric films.

Multistep intermolecular energy migration between elongated fluorophores (carbocyanines) in uniaxially oriented polymer films is studied based on fluorescence depolarization and Monte-Carlo simulations. Contrary to disordered systems it is found experimentally that the concentration depolarization of fluorescence in uniaxially oriented films is extremely weak despite effective energy migration. Based on the concentration depolarization experiment in the ordered matrix it is possible to estimate the angle between absorption and fluorescence transition moments of carbocyanines.

N-(2,4-Dimethoxybenzylideneamino)guanidinium dihydrogenphosphate.

In the asymmetric unit of the title compound, C10H15N4O2+.H2PO4-, there are two protonated aminoguanidinium cations and two dihydrogenphosphate anions. The positive charge on the protonated amidine group is delocalized over the three C-N bonds in a manner similar to that found in guanidinium salts.

Excitation energy transport and trapping in concentrated solid solutions of flavomononucleotide.

Excitation energy transport and trapping is studied for monomer-fluorescent dimer system of flavomononucleotide (FMN) in polyvinyl alcohol films (PVA). It is shown that the theory neglecting reverse energy transfer (RET) from dimers to monomers does not allow for the explanation of concentration quenching and concentration depolarization results presented herein. Much better agreement has been obtained using generalized energy transport theory in which fluorescent dimers are treated as imperfect traps for excitation energy.

Nonradiative excitation energy transport in one-component disordered systems.

High-accuracy Monte Carlo simulations of the time-dependent excitation probabilityG (s) (t) and steady-state emission anisotropyr M /r 0M for one-component three-dimensional systems were performed. It was found that the values ofr M /r 0M obtained for the averaged orientation factor[Formula: see text] only slightly overrate those obtained for the real values of the orientation factor κ ik (2) . This result is essentially different from that previously reported.

Direct and reverse energy transport in systems of monomers and imperfect traps: Monte Carlo simulations.

A Monte Carlo simulation of the concentration dependence of the fluorescence quantum yield ŋM and emission anisotropyr M of a system containing dye molecules in the form of monomers M and clusters T (statistical pairs and trimers) playing the role of the imperfect traps for nonradiative excitation energy transfer (NET) has been carried out. The simulation has been made for determined values of Förster critical distancesR 0 (MM) andR 0 (MT) and for several values ofR 0 (TM) andR 0 (TT) , assuming that the energy may be transferred from M(*) to T as well as from T(*) to M (reverse nonradiative energy transfer, RNET). It was shown that the RNET process in the range of high concentrations may strongly change the values ofr M as well as those of ŋM.

Investigations of the excitation energy transport mechanism in donor-acceptor systems.

Measurements of fluorescence quantum yield ηD/ηoD of Na-fluorescein (donor; D) versus concentration of rhodamine B (acceptor; A) in viscous solutions have been carried out. The donor concentration in these solutions was as follows:C D=2·10(-2) M (system I), 1.5·10(-2) M (II), 10(-2) M (III), 3·10(-3) M (IV), and 5·10(-5) M (V).