Transcription and genome architecture are interdependent, but it is still unclear how nucleosomes in the chromatin fiber interact with nascent RNA, and which is the relative nuclear distribution of these RNAs and elongating RNA polymerase II (RNAP II). Using super-resolution (SR) microscopy, we visualized the nascent transcriptome, in both nucleoplasm and nucleolus, with nanoscale resolution. We found that nascent RNAs organize in structures we termed RNA nanodomains, whose characteristics are independent of the number of transcripts produced over time. Dual-color SR imaging of nascent RNAs, together with elongating RNAP II and H2B, shows the physical relation between nucleosome clutches, RNAP II, and RNA nanodomains. The distance between nucleosome clutches and RNA nanodomains is larger than the distance measured between elongating RNAP II and RNA nanodomains. Elongating RNAP II stands between nascent RNAs and the small, transcriptionally active, nucleosome clutches. Moreover, RNA factories are small and largely formed by few RNAP II. Finally, we describe a novel approach to quantify the transcriptional activity at an individual gene locus. By measuring local nascent RNA accumulation upon transcriptional activation at single alleles, we confirm the measurements made at the global nuclear level.

In this paper, we contribute to the enhancement of routing in unstructured Peer-to-Peer (P2P) systems. Our contribution aims to propose an alternative to the repetitive interactions between peers in discovery which waste considerable time. We propose a methodology that seeks effectiveness and swiftness. Contrary to classic and heuristic-based routing strategies, the main goal of our proposition is that every peer prepares a database at the integration phase. The database includes information about peers, locations, routes to every destination, etc. Every peer possesses its own database and is able to update it whenever a change occurs in the system. Changes refer to the integration of new peers and the dissociation of existing ones. Theoretically, the communication between peers will become significantly quicker since every peer knows enough information about the other peers forming the system. The application of our strategy demonstrates its fitness to the proposed system model in addition to its celerity and relevance.

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In this paper, we propose an indicator to systems-of-systems (SoS) structural analysis through dependencies evaluation which is based on interoperability and exchange inefficiency assessments, with dependencies representing links between component systems within the SoS. Interoperability is a quality that can be viewed from various perspectives. Therefore, we propose an illustrative classification for interoperability that embraces: barriers, scopes and levels. Our study involves a set of metrics to assess each interdependency’s interoperability barriers within the SoS through interoperability levels. Two different case studies, from the Moroccan economic infrastructure, are presented to apply the proposed approach. Results are cross-compared and evaluated.