Effect of charging on CdSe/CdS dot-in-rods single-photon emission

The photon statistics of CdSe/CdS dot-in-rods nanocrystals is studied with a method involving post-selection of the photon detection events based on the photoluminescence count rate. We show that flickering between two states needs to be taken into account to interpret the single-photon emission properties. With post-selection we are able to identify two emitting states: the exciton and the charged exciton (trion), characterized by different lifetimes and different second order correlation functions. Measurements of the second order autocorrelation function at zero delay with post- selection shows a degradation of the single photon emission for CdSe/CdS dot-in-rods in a charged state that we explain by deriving the neutral and charged biexciton quantum yields.Comment: 10 pages, 5 figure

Photon correlations for colloidal nanocrystals and their clusters

Images of semiconductor `dot in rods' and their small clusters are studied by measuring the second-order correlation function with a spatially resolving ICCD camera. This measurement allows one to distinguish between a single dot and a cluster and, to a certain extent, to estimate the number of dots in a cluster. A more advanced measurement is proposed, based on higher-order correlations, enabling more accurate determination of the number of dots in a small cluster. Nonclassical features of the light emitted by such a cluster are analyzed.Comment: 4 pages, 4 figure

Acoustic quality of auditoria: Relationship between acoustical energy parameters and subjective perception

The acoustic design auditoria is founded on objective acoustic parameters determined on the basis of the computed or measured impulse response. Such objective parameters are related on the average response of the human ear to transient sounds, without considering the subjective perception of the individual, which, in turn, is related also to social and education aspects. The aim of this study is to investigate the relationship between individual sound perceptions and energy parameters. In detail, a questionnaire has been submitted to a sample of people listening to tracks of different musical genres. The questionnaire has been conceived to come up with a classification model for the audience allowing to express the listener's experience according to different indicators, such as overall acoustic quality and overall acoustic experience. Results of this experiment are analyzed by means of Random Forest non-parametric model belonging to the data mining algorithms. The final purpose of the study is to define which physical and acoustical characteristics are the most suitable to represent the subjective perceptions of the listeners

An RNA Polymerase III General Transcription Factor Engages in Cell Type-Specific Chromatin Looping

Transcription factors (TFs) bind DNA in a sequence-specific manner and are generally cell type-specific factors and/or developmental master regulators. In contrast, general TFs (GTFs) are part of very large protein complexes and serve for RNA polymerases’ recruitment to promoter sequences, generally in a cell type-independent manner. Whereas, several TFs have been proven to serve as anchors for the 3D genome organization, the role of GTFs in genome architecture have not been carefully explored. Here, we used ChIP-seq and Hi-C data to depict the role of TFIIIC, one of the RNA polymerase III GTFs, in 3D genome organization. We find that TFIIIC genome occupancy mainly occurs at specific regions, which largely correspond to Alu elements; other characteristic classes of repetitive elements (REs) such as MIR, FLAM-C and ALR/alpha are also found depending on the cell’s developmental origin. The analysis also shows that TFIIIC-enriched regions are involved in cell type-specific DNA looping, which does not depend on colocalization with the master architectural protein CTCF. This work extends previous knowledge on the role of TFIIIC as a bona fide genome organizer whose action participates in cell type-dependent 3D genome looping via binding to REs

Refugee protection in the region: a survey and evaluation of current trends

Cities, Migration and Global InterdependenceFdR – Publicaties niet-programma gebonde