4 research outputs found

    Effects of initial-state dynamics on collective flow within a coupled transport and viscous hydrodynamic approach

    Full text link
    We evaluate the effects of preequilibrium dynamics on observables in ultrarelativistic heavy-ion collisions. We simulate the initial nonequilibrium phase within A MultiPhase Transport (AMPT) model, while the subsequent near-equilibrium evolution is modeled using (2+1)-dimensional relativistic viscous hydrodynamics. We match the two stages of evolution carefully by calculating the full energy-momentum tensor from AMPT and using it as input for the hydrodynamic evolution. We find that when the preequilibrium evolution is taken into account, final-state observables are insensitive to the switching time from AMPT to hydrodynamics. Unlike some earlier treatments of preequilibrium dynamics, we do not find the initial shear viscous tensor to be large. With a shear viscosity to entropy density ratio of 0.120.12, our model describes quantitatively a large set of experimental data on Pb+Pb collisions at the Large Hadron Collider(LHC) over a wide range of centrality: differential anisotropic flow vn(pT) (n=2−6)v_n(p_T) ~(n=2-6), event-plane correlations, correlation between v2v_2 and v3v_3, and cumulant ratio v2{4}/v2{2}v_2\{4\}/v_2\{2\}.Comment: 10 pages, v2: minor revisio

    Characterization of the cell growth inhibitory effects of a novel DNA-intercalating bipyridyl-thiourea-Pt(II) complex in cisplatin-sensitive and-resistant human ovarian cancer cells

    No full text
    The cellular effects of a novel DNA-intercalatingagent, the bipyridyl complex of platinum(II) with diphenylthiourea, [Pt(bipy)(Ph2-tu)2]Cl2, has been analyzed in thecisplatin (cDDP)\u2014sensitive human ovarian carcinoma cellline, 2008, and its\u2014resistant variant, C13* cells, in which thehighest accumulation and cytotoxicity was found among sixrelated bipyridyl thiourea complexes. We also show here thatthis complex causes reactive oxygen species to form andinhibits topoisomerase II activity to a greater extent in thesensitive than in the resistant line. The impairment of thisenzyme led to DNA damage, as shown by the comet assay.As a consequence, cell cycle distribution has also beengreatly perturbed in both lines. Morphological analysisrevealed deep cellular derangement with the presence of cellular masses, together with increased membrane permeability and depolarization of the mitochondrial membrane. Some of these effects, sometimes differentially evident between the two cell lines, might also be related to the decrease of total cell magnesium content caused by this thiourea complex both in sensitive and resistant cells, though the basal content of this ion was higher in the cDDP-resistant line. Altogether these results suggest that this compound exerts its cytotoxicity by mechanisms partly mediated by the resistance phenotype. In particular, cDDP-sensitive cells were affected mostly by impairing topoisomerase II activity and by increasing membrane permeability and the formation of reactive oxygen species; conversely, mitochondrial impairment appeared to play the most important role in the action of complex F in resistant cells

    Pretreatment MRI Radiomics Based Response Prediction Model in Locally Advanced Cervical Cancer

    No full text
    The aim of this study was to create a radiomics model for Locally Advanced Cervical Cancer (LACC) patients to predict pathological complete response (pCR) after neoadjuvant chemoradiotherapy (NACRT) analysing T2-weighted 1.5 T magnetic resonance imaging (MRI) acquired before treatment start. Patients with LACC and an International Federation of Gynecology and Obstetrics stage from IB2 to IVA at diagnosis were retrospectively enrolled for this study. All patients underwent NACRT, followed by radical surgery; pCR―assessed on surgical specimen―was defined as absence of any residual tumour. Finally, 1889 features were extracted from MR images; features showing statistical significance in predicting pCR at the univariate analysis were selected following an iterative method, which was ad-hoc developed for this study. Based on this method, 15 different classifiers were trained considering the most significant features selected. Model selection was carried out using the area under the receiver operating characteristic curve (AUC) as target metrics. One hundred eighty-three patients from two institutions were analysed. The model, showing the highest performance with an AUC of 0.80, was the random forest method initialised with default parameters. Radiomics appeared to be a reliable tool in pCR prediction for LACC patients undergoing NACRT, supporting the identification of patient risk groups, which paves treatment pathways tailored according to the predicted outcome

    Mother-to-Infant Microbial Transmission from Different Body Sites Shapes the Developing Infant Gut Microbiome

    No full text
    The acquisition and development of the infant microbiome are key to establishing a healthy host-microbiome symbiosis. The maternal microbial reservoir is thought to play a crucial role in this process. However, the source and transmission routes of the infant pioneering microbes are poorly understood. To address this, we longitudinally sampled the microbiome of 25 mother-infant pairs across multiple body sites from birth up to 4 months postpartum. Strain-level metagenomic profiling showed a rapid influx of microbes at birth followed by strong selection during the first few days of life. Maternal skin and vaginal strains colonize only transiently, and the infant continues to acquire microbes from distinct maternal sources after birth. Maternal gut strains proved more persistent in the infant gut and ecologically better adapted than those acquired from other sources. Together, these data describe the mother-to-infant microbiome transmission routes that are integral in the development of the infant microbiome
    corecore