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.

Energy-Efficient Algorithm for Reliable Routing of Wireless Sensor Networks

Abstract: Quality of service (QoS) routing is one of the critical challenges in wireless sensor networks (WSNs), especially for surveillance systems. Multihop data transmission of WSNs, due to the high packet loss and energy-efficiency, requires reliable links for end-to-end data delivery. Current multipath routing works can provision QoS requirements like end-to-end reliability and delay, but suffer from a significant energy cost. To improve the efficiency of the network with multiconstraints QoS parameters, in this paper we model the problem as a multiconstrained optimal path problem and propose a distributed learning automaton (DLA) based algorithm to preserve it. The proposed approach leverages the advantage of DLA to find the smallest number of nodes to preserve the desired QoS requirements. It takes several QoS routing constraints like end-to-end reliability and delay into account in path selection. We simulate the proposed algorithm, and the obtained results verify the effectiveness of our solution. The results demonstrate that our algorithm has a better performance than current state-of-the-art competitive algorithms in terms of end-to-end delay and energy-efficiency.

Repurposing the antimycotic drug flucytosine for suppression of Pseudomonas aeruginosa pathogenicity

Abstract: Although antibiotic resistance represents a public health emergency, the pipeline of new antibiotics is running dry. Repurposing of old drugs for new clinical applications is an attractive strategy for drug development. We used the bacterial pathogen Pseudomonas aeruginosa as a target for the screening of antivirulence activity among marketed drugs. We found that the antimycotic agent flucytosine inhibits the expression of the iron-starvation σ-factor PvdS, thereby repressing the production of major P. aeruginosa virulence factors, namely pyoverdine, PrpL protease, and exotoxin A. Flucytosine administration at clinically meaningful dosing regimens suppressed P. aeruginosa pathogenicity in a mouse model of lung infection. The in vitro and in vivo activity of flucytosine against P. aeruginosa, combined with its desirable pharmacological properties, paves the way for clinical trials on the anti-P. aeruginosa efficacy of flucytosine in humans.

HIV-1 Nef Induces the Release of Inflammatory Factors from Human Monocyte/Macrophages: Involvement of Nef Endocytotic Signals and NF-κB Activation

Abstract: It has been recently reported that the endogenous expression of HIV-1 Nef in human monocyte/macrophages induces the release of chemokines and other as yet unidentified soluble factors leading to multiple effects of pathogenic significance, such as the recruitment and activation of quiescent lymphocytes. However, the description of underlying molecular mechanisms remained elusive. We recently demonstrated that human monocyte-derived macrophages (MDM) efficiently internalize soluble rNef, thereby inducing effects largely resembling those observed in cells endogenously expressing Nef. By exploiting the rNef/MDM model, we sought to gain more insights on the molecular mechanisms underlying the response of MDM to Nef. Array analysis for the detection of transcripts from a large number of monokines, chemokines, cytokines, and receptors thereof showed that MDM promptly responded to rNef treatment by increasing the transcription of genes for several inflammatory factors. Analysis of supernatants revealed that rNef treatment induced the release of macrophage inflammatory proteins 1alpha and 1beta, IL-1beta, IL-6, and TNF-alpha. Conversely, rNefs mutated in domains critical for the interaction with the endocytotic machinery (i.e., EE155-156QQ, and DD174-175AA) were ineffective. Interestingly, we found that the Nef-dependent release of inflammatory factors correlated with the activation of the NF-kappaB transcription factor, mainly in its p50/p50 homodimeric form, and in a de novo protein synthesis-independent manner. Our data add new hints supporting the idea that the presence of Nef is per se heavily detrimental for monocyte/macrophages and relative cross-talking cell types.

The WISSH Quasars Project I. Powerful ionised outflows in hyper-luminous quasars

Abstract: Models and observations suggest that both the power and effects of AGN feedback should be maximised in hyper-luminous (L Bol > 1047 erg s-1 ) quasars, i.e. objects at the brightest end of the AGN luminosity function. In this paper, we present the first results of a multiwavelength observing programme, focusing on a sample of WISE/SDSS selected hyper-luminous (WISSH) broad-line quasars at z ≈ 1.5–5. The WISSH quasars project has been designed to reveal the most energetic AGN-driven outflows, estimate their occurrence at the peak of quasar activity, and extend the study of correlations between outflows and nuclear properties up to poorly investigated, extreme AGN luminosities, i.e. L Bol ~ 1047 − 1048 erg s-1 . We present near-infrared, long-slit LBT/LUCI1 spectroscopy of five WISSH quasars at z ≈ 2.3 − 3.5, showing prominent [OIII] emission lines with broad (FWHM ~1200–2200 km s-1 ) and skewed profiles. The luminosities of these broad [OIII] wings are the highest measured so far, with L [OIII ] broad ≳ 5 × 1044 erg s-1 , and reveal the presence of powerful ionised outflows with associated mass outflow rates Ṁ ≳ 1700M ⊙ yr-1 and kinetic powers Ė kin ≳ 1045 erg s-1 . Although these estimates are affected by large uncertainties because of the use of [OIII] as a tracer of ionised outflows and the very basic outflow model adopted here, these results suggest that in our hyper-luminous targets the AGN is highly efficient at pushing large amounts of ionised gas outwards. Furthermore, the mechanical outflow luminosities measured for WISSH quasars correspond to higher percentages (~1–3%) of L Bol than those derived for AGN with lower L Bol . Our targets host very massive (M BH ≳ 2 × 109 M ⊙ ) black holes that are still accreting at a high rate (i.e. a factor of ~0.4–3 of the Eddington limit). These findings clearly demonstrate that WISSH quasars offer the opportunity to probe the extreme end of both luminosity and supermassive black holes (SMBH) mass functions and revealing powerful ionised outflows that are able to affect the evolution of their host galaxies.