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The dynamics of a nuclear open quantum system could be revealed in the correlations between the breakup fragments of halo nuclei. The breakup mechanism of a proton halo nuclear system is of particular interest as the Coulomb polarization may play an important role, which, however, remains an open question. Here we use a highly efficient silicon detector array and measure the correlations between the breakup fragments of 8B incident on 120Sn at near-barrier energies. The energy and angular correlations can be explained by a fully quantum mechanical method based on the state-of-the-art continuum discretized coupled channel calculations. The results indicate that, compared to the neutron halo nucleus 6He, 8B presents distinctive reaction dynamics: the dominance of the elastic breakup. This breakup occurs mainly via the short-lived continuum states, almost exhausts the 7Be yield, indicating the effect of Coulomb polarization on the proton halo state. The correlation information reveals that the prompt breakup mechanism dominates, occurring predominantly on the outgoing trajectory. We also show that, as a large environment, the continuum of 8B breakup may not significantly influence elastic scattering and complete fusion.

In 1985, Hussein and McVoy [Nuc. Phys. A445 (1985) 124] elucidated a formula for the evaluation of the nonelastic breakup (“stripping”) contribution in inclusive breakup reactions. The formula, based on the spectator core model, acquires a particularly simple and appealing form in the eikonal limit, to the extent that it has become the standard procedure to analyze single-nucleon knockout reactions at intermediate energies. In this contribution, a critical assessment of this formula is presented and its connection with other, noneikonal expressions discussed. Some calculations comparing the different formulae are also presented for the one-nucleon removal of $$^{14}$$ O+ $$^{9}$$ Be reaction at several incident energies.

Analyzing the research productivity of a country, an academic institution or even a single research group contributes to understand how science evolves and discovers new research perspectives, since such efforts usually reveal key aspects that can be improved, avoided or even applied to other contexts. In this article, we present a detailed analysis of the top Brazilian Computer Science graduate programs. The analysis involves profile data on faculty members (e.g., career length and number of mentored students) and on the quality of their research efforts, assessed using the quality of their publications and collaboration patterns. The objective is to uncover factors that explain the strengths and weaknesses of graduate programs. Results show that the highest ranked programs include more experienced faculty members, who have mentored more Ph.D. students. We also show that programs target distinct publication venues, with the best ranked ones focusing on higher quality conferences and journals. By analyzing collaboration patterns, we show that intra-program relationships occur quite naturally whereas inter-program ones are still very incipient.

Environmental exposure to pollutants, especially polycyclic aromatic hydrocarbons (PAHs), could lead to carcinogenesis development. However, there is a gap on the mechanisms involved in this effect. Therefore, the aim of this study was to investigate the potential relationship between exposure to environmental air pollution and inflammation process in DNA damage in taxi drivers. This study included 45 taxi drivers and 40 controls; non-smokers composed both groups. Biological monitoring was performed through quantification of urinary 1-hydroxypyrene (1-OHP). ICAM-1 (CD54) expression, NTPDase activity, inflammatory cytokine (IL-1β, IL-6, IL-10, TNF-α and IFN-γ) levels, and comet and micronucleus assays were evaluated. The results demonstrated that 1-OHP levels, ICAM-1 expression, NTPDase activity, and DNA damage biomarkers (% tail DNA and micronucleus frequency) were increased in taxi drivers compared to the control group (p

The problem of the calculation of inclusive breakup cross sections in nuclear reactions is reexamined. For that purpose, the theory proposed by Ichimura et al. (Phys Rev C 32:431, 1985) is revisited, both in its prior and post representations. We briefly outline the connection of this theory with that proposed by Udagawa and Tamura (Phys Rev C 24:1348, 1981) and apply both theories to the inclusive breakup of $$^6$$ Li on $$^{209}$$ Bi at near-barrier energies, comparing also with available data. The relative importance of elastic versus non-elastic breakup, as a function of the incident energy and of the projectile separation energy, is also investigated.

Studying research productivity is a challenging task that is important for understanding how science evolves and crucial for agencies (and governments). In this context, we propose an approach for quantifying the scientific performance of a community (group of researchers) based on the similarity between its publication profile and a reference community's publication profile. Unlike most approaches that consider citation analysis, which requires access to the content of a publication, we only need the researchers' publication records. We investigate the similarity between communities and adopt a new metric named Volume Intensity. Our goal is to use Volume Intensity for measuring the internationality degree of a community. Our experimental results , using Computer Science graduate programs and including both real and random scenarios, show we can use publication profile as a performance indicator.

We present an account of the current status of the theoretical treatment of inclusive $(d,p)$ reactions in the breakup-fusion formalism, pointing to some applications and making the connection with current experimental capabilities. Three independent implementations of the reaction formalism have been recently developed, making use of different numerical strategies. The codes also originally relied on two different but equivalent representations, namely the prior (Udagawa-Tamura, UT) and the post (Ichimura-Austern-Vincent, IAV) representations. The different implementations have been benchmarked, and then applied to the Ca isotopic chain. The neutron-Ca propagator is described in the Dispersive Optical Model (DOM) framework, and the interplay between elastic breakup (EB) and non-elastic breakup (NEB) is studied for three Ca isotopes at two different bombarding energies. The accuracy of the description of different reaction observables is assessed by comparing with experimental data of $(d,p)$ on $^{40,48}$Ca. We discuss the predictions of the model for the extreme case of an isotope ($^{60}$Ca) currently unavailable experimentally, though possibly available in future facilities (nominally within production reach at FRIB). We explore the use of $(d,p)$ reactions as surrogates for $(n,\gamma)$ processes, by using the formalism to describe the compound nucleus formation in a $(d,p\gamma)$ reaction as a function of excitation energy, spin, and parity. The subsequent decay is then computed within a Hauser-Feshbach formalism. Comparisons between the $(d,p\gamma)$ and $(n,\gamma)$ induced gamma decay spectra are discussed to inform efforts to infer neutron captures from $(d,p\gamma)$ reactions. Finally, we identify areas of opportunity for future developments, and discuss a possible path toward a predictive reaction theory.

The reaction 12C(7Be,3He) has been studied at E(7Be) = 34 MeV. Angular distributions to levels with excitation energies up to 21 MeV in the residual 16O have been measured at θlab = 13–50 degrees. This reaction selectively populates states known to have a large 12C+α component in their structure, implying that direct processes dominates at this energy.

A recently proposed procedure for discretizing the continuum is applied to study structure and collision processes of weakly bound nuclei. In particular this paper is concentrated in the deuteron.

The p-6He inelastic scattering at 700 MeV u-1 is studied using Multiple Scattering expansion of the total Transition amplitude (MST) framework with a pseudo-state representation of 6He continuum. We show that the differential cross sections calculated with two different pseudo-state bases are in good agreement.

Retinopathy of prematurity (ROP) is a common cause of blindness in preterm infants worldwide, despite laser treatment. Animal models of oxygeninduced retinopathy (OIR) have been developed to investigate physiological events that lead to the occurrence of this disease. It is known that endothelial progenitor cells (EPCs), derived from bone-marrow, are involved in vascular repair and neovascularization. In the present study we investigate the retinal expression of the SDF-1/ CXCR4 axis, its role in the recruitment of EPCs to the hypoxic retina, and the relationship between these cells and the development of neovascularization in a 50/10 OIR rat model. Our results show increased production of SDF-1 by endothelial cells and neurons in OIR retinas, and enhanced expression of CXCR4 mainly in Muller cells. We have also found in peripheral blood of OIR rats a decreased number of colony-forming units of EPCs. Whether this is due to the presence of functionally impaired EPCs or to the inability of an exhausted bone-marrow to produce enough progenitor cells to cope with the high demands of the process of retinal neovacularization, remains unanswered. We demonstrate in this study that SDF-1/CXCR4 axis, EPCs dysfunction and probably Muller cells, are involved in retinal neovascularization in a 50/10 rat model of OIR. These results warrant further studies.

c-Abl protein tyrosine kinase activity is tightly regulated in vertebrate cells. Several mutations can activate Abl and convert it into an oncogene. In man, chromosomal translocations result in fusion proteins associated with chronic myelogenous leukemias and some acute lymphocytic leukemias. In viral forms of abl, gag sequences are fused to Abl portions resulting in a deletion of N-terminal sequences. To study c-Abl activity in a cellular environment likely to lack specific regulators, we have expressed human c-Abl in Schizosaccharomyces pombe in an inducible fashion. c-Abl causes growth arrest followed by death of the cells. Mutations in the SH2 domain or in the autophosphorylation site dramatically reduce the ability of Abl to confer the growth arrest phenotype and to phosphorylate endogenous proteins, suggesting a fundamental role of these structures in the activity of the enzyme. An SH3 domain deletion mutant of Abl is as active as c-Abl in yeast indicating that there is no intrinsic regulation of c-Abl occurring via the SH3 domain and suggesting that the inhibitory effect of the SH3 domain observed in cells of vertebrate origin is mediated by a factor that is absent in fission yeast. We have used this assay to functionally screen a human cDNA library for molecules able to counteract the lethal effect of c-Abl expression. We are currently in the process of characterising the isolated clones. We hope to identify among them the molecule(s) responsible for regulating c-Abl activity in human cells.

376 Postnatal Growth Restriction in VLBW Infants in Spanish NICUs. A Multicentric Study(SEN 1500 Network).