2,226 research outputs found

    A multi-wavelength view of the central kiloparsec region in the Luminous Infrared Galaxy NGC1614

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    The Luminous Infrared Galaxy NGC1614 hosts a prominent circumnuclear ring of star formation. However, the nature of the dominant emitting mechanism in its central ~100 pc is still under debate. We present sub-arcsecond angular resolution radio, mid-infrared, Pa-alpha, optical, and X-ray observations of NGC1614, aimed at studying in detail both the circumnuclear ring and the nuclear region. The 8.4 GHz continuum emission traced by the Very Large Array (VLA) and the Gemini/T-ReCS 8.7 micron emission, as well as the Pa-alpha line emission, show remarkable morphological similarities within the star-forming ring, suggesting that the underlying emission mechanisms are tightly related. We used an HST/NICMOS Pa-alpha map of similar resolution to our radio maps to disentangle the thermal free-free and non-thermal synchrotron radio emission, from which we obtained the intrinsic synchrotron power-law for each individual region within the central kpc of NGC1614. The radio ring surrounds a relatively faint, steep-spectrum source at the very center of the galaxy, suggesting that the central source is not powered by an AGN, but rather by a compact (r < 90 pc) starburst. Chandra X-ray data also show that the central kpc region is dominated by starburst activity, without requiring the existence of an AGN. We also used publicly available infrared data to model-fit the spectral energy distribution of both the starburst ring and a putative AGN in NGC1614. In summary, we conclude that there is no need to invoke an AGN to explain the observed bolometric properties of the galaxy.Comment: 13 pages, 7 figures, 5 tables. Accepted for publication in Ap

    Exosomes in head and neck cancer. Updating and revisiting

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    Exosomes have gone from being considered simple containers of intracellular waste substances to be considered important carriers of cellular signals. Its broad capacity to promote tumour growth, both in situ and metastatic, has greatly intensified scientific research on them. In the same way and depending on its content, its tumour suppressive properties have opened a window of light and hope in the fight against cancer. In the present review we try to gather in a simple and understandable way the most relevant knowledge to date on the role of exosomes in oral squamous cell carcinoma, helping to understand their process of formation, release and activity on the tumour microenvironment

    Carbon input threshold for soil carbon budget optimization in eroding vineyards

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    Previous studies have documented that, relative to conventional tillage (CT), alternative soil management (reduced tillage, mulching, or cover crops) decreases soil erosion and increases soil organic matter (SOM) in vineyards. These previous studies, however, failed to consider the loss of soil organic carbon (SOC) with erosion that could occur with the adoption of agro-environmental measures (AEM) in a semiarid environment. Accordingly, the aims of this study were to determine whether changes in SOC content under AEM management are always positive and to develop a conceptual model for estimating the "SOC threshold". The SOC threshold was defined as that level of SOC in an AEM-managed vineyard above which erosion will result in greater loss of C than occur in a comparable vineyard with CT management. SOC was analyzed at a 100 paired sites (vineyards with AEM management vs. CT). The results showed that in some cases the loss of C was higher with AEM than with CT. Overall, the results indicate that the SOC threshold may be a key parameter in determining the best AEM measures for vineyards that are on slopes and therefore vulnerable to erosion

    STUDY OF THE O-18+Ni-64 TWO-NEUTRON TRANSFER REACTION AT 84 MeV BY MAGNEX

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    A study of the two-neutron transfer reaction of the O-18 + Ni-64 system at 84 MeV incident energy to the ground and first 2(+) excited state of the residual Ni-66 nucleus is presented. The experiment was performed at the INFN-LNS (Italy) by using the large acceptance MAGNEX spectrometer. Theoretical models are used in order to disentangle the competition between long-range and short-range correlations

    The effect of the crisis on material deprivation in Italy and Spain

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    The focus of this paper is on the analysis of the impact of the crisis on material deprivation in two South European countries: Italy and Spain. The countries chosen have been deeply hit by the economic downturn and the use of the available comparable microdata allows us to detect the most vulnerable collective in the crisis taking into account also gender differences. The microdata used are the Italian and Spanish Income and Living Conditions Surveys of 2007 and 2010. Our results confirm the growth of deprivation as a consequence of the economic crisis in both countries and show that women are more likely to face income poverty and deprivation

    Measuring the impact of the crisis on unemployment and household income

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    The current economic crisis has significantly increased unemployment rates and its effect is more persistent than expected, leading to an increase in long term unemployment and inactivity. Among other effects, the experience of unemployment results in a decrease in purchasing power, a loss of human capital, a discouraging effect among the long-term unemployed and the inactive as well as wide-ranging social costs as a worsening of inequality and well-being indicators. The assessment of the costs of unemployment on individuals and households' living conditions is usually carried out using microeconomic data from household surveys that are however issued with delay. Hence, they do not allow for a prompt analysis of the impact of the economic cycle to guide policy makers. In the case of the European Income and Living Conditions Surveys (EU SILC) the data are available with a delay of at least one year and, additionally, we have to consider that the income data refers to the year before the survey (for instance, in the Italian case the last available microdata at the moment of writing this paper are from 2011). To solve this problem we carried out a microsimulation analysis using the European Statistics on Income and Living Conditions Surveys together with the Labour Force Survey (LFS) microdata. Therefore, we propose a methodology based on different sources of microdata that could provide the analysts and the policy makers with a more immediate analysis of the costs of unemployment. This would prove to be extremely useful in a time of high unemployment and budgetary restrictions as the one in which we find ourselves in today. The microsimulation technique developed in this paper is based on the imputation of transition probabilities and simulated income. Unlike other techniques such as the re- weighting approach, the microsimulation technique adopted here allows us to take into account the changes occurred in the composition of the unemployed. To test the validity of the proposed methodology we apply it to Italy, a European country severely hit by the crisis. We focus on the Italian economy since this country is a member of the Eurozone and its labour market has particular structural characteristics: a high degree of inflexibility in wage determination, rigidity in hiring and firing practices, very low achievement in terms of female labour-force participation and a strong duality between fixed-term and open-ended contracts. The country has an employment protection system corresponding to the Mediterranean model that is characterized by a rather low coverage of unemployment benefit moreover, the wide use of temporary contracts in hiring young workers to avoid the much higher dismissal costs of permanent contracts coupled with the deep recession, have resulted in a youth unemployment rate standing well over the European average. In Section 2 we introduce the methodology that will be used to microsimulate the effect of the crisis on income distribution and income poverty in Section 3 by relying on European surveys. In order to check its validity, we do progress with its application to Italy in Section 4. The final section will offer conclusions

    Systemic Effects Induced by Hyperoxia in a Preclinical Model of Intra-abdominal Sepsis

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    Supplemental oxygen is a supportive treatment in patients with sepsis to balance tissue oxygen delivery and demand in the tissues. However, hyperoxia may induce some pathological effects. We sought to assess organ damage associated with hyperoxia and its correlation with the production of reactive oxygen species (ROS) in a preclinical model of intra-abdominal sepsis. For this purpose, sepsis was induced in male, Sprague-Dawley rats by cecal ligation and puncture (CLP). We randomly assigned experimental animals to three groups: control (healthy animals), septic (CLP), and sham-septic (surgical intervention without CLP). At 18 h after CLP, septic (n = 39), sham-septic (n = 16), and healthy (n = 24) animals were placed within a sealed Plexiglas cage and randomly distributed into four groups for continuous treatment with 21%, 40%, 60%, or 100% oxygen for 24 h. At the end of the experimental period, we evaluated serum levels of cytokines, organ damage biomarkers, histological examination of brain and lung tissue, and ROS production in each surviving animal. We found that high oxygen concentrations increased IL-6 and biomarkers of organ damage levels in septic animals, although no relevant histopathological lung or brain damage was observed. Healthy rats had an increase in IL-6 and aspartate aminotransferase at high oxygen concentration. IL-6 levels, but not ROS levels, are correlated with markers of organ damage. In our study, the use of high oxygen concentrations in a clinically relevant model of intra-abdominal sepsis was associated with enhanced inflammation and organ damage. These findings were unrelated to ROS release into circulation. Hyperoxia could exacerbate sepsis-induced inflammation, and it could be by itself detrimental. Our study highlights the need of developing safer thresholds for oxygen therapy

    Long-range versus short-range correlations in the two-neutron transfer reaction Ni 64 (O 18, O 16) Ni 66

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    Recently, various two-neutron transfer studies using the (18O,16O) reaction were performed with a large success. This was achieved because of a combined use of the microscopic quantum description of the reaction mechanism and of the nuclear structure. In the present work we use this methodology to study the two-neutron transfer reaction of the 18O+64Ni system at 84 MeV incident energy, to the ground and first 2+ excited state of the residual 66Ni nucleus. All the experimental data were measured by the large acceptance MAGNEX spectrometer at the Instituto Nazionale di Fisica Nucleare \u2013Laboratori Nazionali del Sud (Italy). We have performed exact finite range cross section calculations using the coupled channel Born approximation (CCBA) and coupled reaction channel (CRC) method for the sequential and direct two-neutron transfers, respectively. Moreover, this is the first time that the formalism of the microscopic interaction boson model (IBM-2) was applied to a two-neutron transfer reaction. From our results we conclude that for two-neutron transfer to the ground state of 66Ni, the direct transfer is the dominant reaction mechanism, whereas for the transfer to the first excited state of 66Ni, the sequential process dominates. A competition between long-range and short-range correlations is discussed, in particular, how the use of two different models (Shell model and IBM's) help to disentangle long- and short-range correlations

    Effect of antiseptic gels in the microbiologic colonization of the suture threads after oral surgery

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    Three different bioadhesive gels were evaluated in a double-blind randomized clinical trial in which microbial growth in the suture thread was assessed following post-surgical application of the aforementioned gels. Also assessed in this trial were, the intensity of post-surgical pain as well as the degree of healing of the patients' surgical wounds. A total of 21 patients (with 42 wisdom teeth) participated in this trial. Chlorhexidine gel, chlorhexidine-chitosan gel, and hyaluronic acid gel were evaluated, with a neutral water-based gel serving as the control agent. The aerobic and facultative anaerobic bacterial recovery on blood agar was lower in the placebo group than in the experimental groups. The most significant difference (p = 0.04) was observed in the chlorhexidine-chitosan group. in which the growth of Blood Agar and Mitis Salivarius Agar was significantly higher than in the placebo group. The intensity of post-surgical pain was very similar among all the groups. Significantly better healing rates were observed in the patients treated with chlorhexidine-chitosan gel when compared with those who used the placebo gel (p = 0.03), and in particular when compared with those patients who used hyaluronic acid gel (p = 0.01). Through our microbiological analyses, we were able to conclude that none of the bioadhesive gels tested resulted in beneficial reductions in the bacterial/fungal populations. However, the healing rates of patients who were treated with chlorhexidine-chitosan were better than those of the patients who used either the placebo gel or the hyaluronic acid gel

    Spin dynamics for bosons in an optical lattice

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    We study the internal dynamics of bosonic atoms in an optical lattice. Within the regime in which the atomic crystal is a Mott insulator with one atom per well, the atoms behave as localized spins which interact according to some spin Hamiltonian. The type of Hamiltonian (Heisenberg, Ising), and the sign of interactions may be tuned by changing the properties of the optical lattice, or applying external magnetic fields. When, on the other hand, the number of atoms per lattice site is unknown, we can still use the bosons to perform general quantum computation
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