Roma Tre University

About: Roma Tre University is a education organization based out in Rome, Lazio, Italy. It is known for research contribution in the topics: Large Hadron Collider & Galaxy. The organization has 4434 authors who have published 15352 publications receiving 374888 citations. The organization is also known as: Universita degli Studi Roma Tre & RomaTre.

The XMM–Newton long look of NGC 1365: uncovering of the obscured X-ray source

Abstract: We present an analysis of the extreme obscuration variability observed during an XMM–Newton 5-d continuous monitoring of the active galactic nuclei (AGN) in NGC 1365. The source was in a reflection-dominated state in the first ∼1.5 d, then a strong increase in the 7–10 keV emission was observed in ∼10 h, followed by a symmetric decrease. The spectral analysis of the different states clearly shows that this variation is due to an uncovering of the X-ray source. From this observation, we estimate a size of the X-ray source DS < 1013 cm, a distance of the obscuring clouds R∼ 1016 cm and a density n∼ 1011 cm−3. These values suggest that the X-ray absorption/reflection originates from the broad-line region clouds. This is also supported by the resolved width of the iron narrow Kα emission line, consistent with the width of the broad Hβ line.

Unravelling the Genome-Wide Contributions of Specific 2-Alkyl-4-Quinolones and PqsE to Quorum Sensing in Pseudomonas aeruginosa.

Abstract: The pqs quorum sensing (QS) system is crucial for Pseudomonas aeruginosa virulence both in vitro and in animal models of infection and is considered an ideal target for the development of anti-virulence agents. However, the precise role played by each individual component of this complex QS circuit in the control of virulence remains to be elucidated. Key components of the pqs QS system are 2-heptyl-4-hydroxyquinoline (HHQ), 2-heptyl-3-hydroxy-4-quinolone (PQS), 2-heptyl-4-hydroxyquinoline N-oxide (HQNO), the transcriptional regulator PqsR and the PQS-effector element PqsE. To define the individual contribution of each of these components to QS-mediated regulation, transcriptomic analyses were performed and validated on engineered P. aeruginosa strains in which the biosynthesis of 2-alkyl-4-quinolones (AQs) and expression of pqsE and pqsR have been uncoupled, facilitating the identification of the genes controlled by individual pqs system components. The results obtained demonstrate that i) the PQS biosynthetic precursor HHQ triggers a PqsR-dependent positive feedback loop that leads to the increased expression of only the pqsABCDE operon, ii) PqsE is involved in the regulation of diverse genes coding for key virulence determinants and biofilm development, iii) PQS promotes AQ biosynthesis, the expression of genes involved in the iron-starvation response and virulence factor production via PqsR-dependent and PqsR-independent pathways, and iv) HQNO does not influence transcription and hence does not function as a QS signal molecule. Overall this work has facilitated identification of the specific regulons controlled by individual pqs system components and uncovered the ability of PQS to contribute to gene regulation independent of both its ability to activate PqsR and to induce the iron-starvation response.

Search for a light charged Higgs boson in the decay channel H+ -> c(s)over-bar in t(t)over-bar events using pp collisions at root s=7 TeV with the ATLAS detector

Abstract: A search for a charged Higgs boson (H+) in t (t) over bar decays is presented, where one of the top quarks decays via t -> H(+)b, followed by H+ -> two jets (c (s) over bar). The other top qu ...

Latest advances on solar thermal collectors: A comprehensive review

Abstract: The need to put in place alternative energy policies stems from the awareness that fossil fuels are exhaustible and harmful to the environment. For this reason, during the last decades the scientific world has focused on systems able to use and convert renewable energy sources, particularly solar radiation. Nowadays, solar thermal collectors use solar energy to distribute low-cost domestic and industrial heating. In this review a comprehensive analysis of peer-reviewed journals and relevant papers on solar thermal collectors is provided. Descriptions of the different types of solar collectors are provided. Theoretical analyses, latest developments related to the functional elements, and hybrid systems have been considered throughout this analysis. Performance test methods for solar thermal collectors and standards are discussed. This cross-review aims to assist researchers, engineers and manufacturers in keeping them abreast of latest developments in the field of solar thermal collectors.

Search for heavy neutrinos and right-handed W bosons in events with two leptons and jets in pp collisions at √s =7 TeV with the ATLAS detector

Abstract: This letter reports on a search for hypothetical heavy neutrinos, N, and right-handed gauge bosons, W-R, in events with high transverse momentum objects which include two reconstructed leptons and ...