2,740 research outputs found

    Super star cluster feedback driving ionization, shocks and outflows in the halo of the nearby starburst ESO 338-IG04

    Full text link
    Stellar feedback strongly affects the interstellar medium (ISM) of galaxies. Stellar feedback in the first galaxies likely plays a major role in enabling the escape of LyC photons, which contribute to the re-ionization of the Universe. Nearby starburst galaxies serve as local analogues allowing for a spatially resolved assessment of the feedback processes in these galaxies. We characterize the feedback effects from the star clusters in the local high-redshift analogue ESO 338-IG04 on the ISM and compare the results with the properties of the most massive clusters. We use high quality VLT/MUSE optical integral field data to derive the physical properties of the ISM such as ionization, density, shocks, and perform new fitting of the spectral energy distributions of the brightest clusters in ESO 338-IG04 from HST imaging. ESO 338-IG04 has a large ionized halo which we detect to a distance of 9 kpc. We identify 4 Wolf-Rayet (WR) clusters based on the blue and red WR bump. We follow previously identified ionization cones and find that the ionization of the halo increases with distance. Analysis of the galaxy kinematics shows two complex outflows driven by the numerous young clusters in the galaxy. We find a ring of shocked emission traced by an enhanced [OI]/Hα\alpha ratio surrounding the starburst and at the end of the outflow. Finally we detect nitrogen enriched gas associated with the outflow, likely caused by the WR stars in the massive star clusters. Photo-ionization dominates the central starburst and sets the ionization structure of the entire halo, resulting in a density bounded halo, facilitating the escape of LyC photons. Outside the central starburst, shocks triggered by an expanding super bubble become important. The shocks at the end of the outflow suggest interaction between the hot outflowing material and the more quiescent halo gas.Comment: Accepted for publication in Astronomy and Astrophysics, 22 pages, 15 figure

    Monitoring and recording changes in natural landscapes: A case study from two coastal wetlands in se italy

    Get PDF
    This study analyzed and evaluated the changes that occurred in two coastal wetlands, characterized by complex and fragmented landscape patterns, in Southern Italy, which were moni-tored over a period of seven years from 2007 to 2014. Furthermore, the performances of two Land Cover (LC) and habitat taxonomies, compared for their suitability in mapping the identified changes, were assessed. A post-mapping method was adopted to detect the habitat/LC changes that occurred in the study period. Various changes were identified, both inter-class changes (class conversions) and intra-class changes (class modifications), and quantified by means of transition matrices. Conversions were easily mapped, while the modification mapping depended on the taxonomy adopted: the Land Cover Classification System (LCCS) allowed the detection of morpho-structural changes in woody vegetation, but the European Nature Information System (EUNIS) showed a higher thematic resolution for the salt marsh types. The detected changes were related to specific impacts, pressures and underlying factors. Landscape indices highlighted different trends in landscape richness and complexity in the two sites. Changes are occurring very quickly in the observed coastal sites and the ongoing dynamics are strictly related to their small size and complexity. For effective monitoring and detection of change in these environments, the coupling of EUNIS and LCCS is suggested

    Measles among healthcare workers in Italy. Is it time to act?

    Get PDF
    Vaccination of healthcare workers (HCWs) against measles is strongly recommended in Europe. In this study, we examined the impact of measles on Italian HCWs by systematically and quantitatively analyzing measles cases involving HCWs over time and by identifying the epidemiological characteristics of the respective measles outbreaks. We retrieved data on measles cases from the Italian national integrated measles and rubella surveillance system from January 2013 to May 2019. Additionally, we performed a systematic review of the literature and an analysis of the measles and rubella aggregate outbreaks reporting forms from 2014 to 2018. Our review suggests that preventing measles infection among HCWs in disease outbreaks may be crucial for the elimination of measles in Italy. National policies aiming to increase HCW immunization rates are fundamental to the protection of HCWs and patients, will limit the economic impact of outbreaks on the institutions affected and will help achieve the elimination goal

    Safety and activity of trastuzumab-containing therapies for the treatment of metastatic breast cancer: our long-term clinical experience (GOIM study).

    Get PDF
    Background: Trastuzumab is widely used as the treatment of choice for HER2-positive metastatic breast cancer (MBC). Patients and methods: Seventy patients, median age 57 years and range 31–81 years, were included in our retrospective analysis with the aim to evaluate safety and activity of trastuzumab-containing therapies. Results: We observed for first-line treatment response rate (RR) 41%, stable disease (SD) 47% and time to progression (TTP) 8 months (range 1–44). Corresponding numbers for second line were RR 23%, SD 62% and (TTP) 9 months (range 3–23) and beyond second line RR 22%, SD 78% and (TTP) 9 months (range 4–19). Overall survival was 19.2 months (3–62 months). The median cumulative dose of trastuzumab administrated was 5286 mg (464–17 940 mg). Trastuzumab was well tolerated. Median left ventricular ejection function (LVEF) at baseline was 62% and at the end of treatment was 59%. The more relevant adverse events consisted of an asymptomatic decrease in LVEF to 40% (baseline 60%) and a grade 3 symptomatic increase in bilirubin. Conclusion: Trastuzumab-containing therapies in MBC show a good safety and toxicity profile and a remarkable activity even in heavily pretreated women. Patients should benefit from continued trastuzumab therapy, as shown by the maintenance of (TTP) even beyond second-line treatment

    Spin and lattice excitations of a BiFeO3 thin film and ceramics

    Full text link
    We present a comprehensive study of polar and magnetic excitations in BiFeO3 ceramics and a thin film epitaxially grown on an orthorhombic (110) TbScO3 substrate. Infrared reflectivity spectroscopy was performed at temperatures from 5 to 900 K for the ceramics and below room temperature for the thin film. All 13 polar phonons allowed by the factor-group analysis were observed in theceramic samples. The thin-film spectra revealed 12 phonon modes only and an additional weak excitation, probably of spin origin. On heating towards the ferroelectric phase transition near 1100 K, some phonons soften, leading to an increase in the static permittivity. In the ceramics, terahertz transmission spectra show five low-energy magnetic excitations including two which were not previously known to be infrared active; at 5 K, their frequencies are 53 and 56 cm-1. Heating induces softening of all magnetic modes. At a temperature of 5 K, applying an external magnetic field of up to 7 T irreversibly alters the intensities of some of these modes. The frequencies of the observed spin excitations provide support for the recently developed complex model of magnetic interactions in BiFeO3 (R.S. Fishman, Phys. Rev. B 87, 224419 (2013)). The simultaneous infrared and Raman activity of the spin excitations is consistent with their assignment to electromagnons

    Evolution of magnetic phases and orbital occupation in (SrMnO3)n/(LaMnO3)2n superlattices

    Full text link
    The magnetic and electronic modifications induced at the interfaces in (SrMnO3_{3})n_{n}/(LaMnO3_{3})2n_{2n} superlattices have been investigated by linear and circular magnetic dichroism in the Mn L2,3_{2,3} x-ray absorption spectra. Together with theoretical calculations, our data demonstrate that the charge redistribution across interfaces favors in-plane ferromagnetic (FM) order and eg(x2−y2)e_{g}(x^{2}-y^{2}) orbital occupation, in agreement with the average strain. Far from interfaces, inside LaMnO3_3, electron localization and local strain favor antiferromagnetism (AFM) and eg(3z2−r2)e_{g}(3z^{2}-r^{2}) orbital occupation. For n=1n=1 the high density of interfacial planes ultimately leads to dominant FM order forcing the residual AFM phase to be in-plane too, while for n≥5n \geq 5 the FM layers are separated by AFM regions having out-of-plane spin orientation.Comment: accepted for publication as a Rapid Communication in Physical Review

    The Risk of Toxicities from Trastuzumab, Alone or in Combination, in an Elderly Breast Cancer Population

    Get PDF
    Abstract Background: Breast cancer in the elderly is associated with high recurrence and death rates, due mostly to undertreatment. Human epidermal growth factor receptor type 2 (HER2) overexpression is infrequent in older patients. Trastuzumab- based chemotherapy is often withheld from elderly patients because of its cardiotoxicity. Patients and Methods: Medical records of consecutive HER2-positive breast cancer patients aged 65 70 years old treated between 2005 and 2010 in the participating centers were retrospectively reviewed. All patients underwent multidimensional geriatric assessment (MGA). Results: Among 59 patients identified, 51 patients were evaluable (median age 76 years). The rate of any adverse event was 20% (10/51). The most relevant cardiac adverse event consisted of symptomatic congestive heart failure (CHF; n = 1, 2%) followed by asymptomatic decreases of left ventricular ejection fraction (LVEF; n = 6, 12%). Other toxicities included moderate hypersensitivity reactions during trastuzumab infusions (n = 3, 6%). Hypertension, obesity, prior anthracyclines exposure and concurrent chemotherapy were associated with a higher incidence of toxic events. Previous radiotherapy, concurrent endocrine therapy and different trastuzumab-based regimens did not seem to influence toxicity. Conclusions: Our data suggest that trastuzumab has a good safety profile in nonfrail women aged 70 years and older. These favorable findings may be related to a limited number of anthracycline pretreatments, patient selection and a close cardiologic monitoring

    The role of Aurora-A inhibitors in cancer therapy.

    Get PDF
    Recently, new chemotherapy agents which target the non-structural components of mitosis have been developed. An important protein involved in several mitotic phases is the Aurora-A protein. By means of the phosphorylation of different substrates, Aurora-A regulates the correct development of the various phases of mitosis. The kinase activity of this protein makes Aurora-A an excellent candidate as an oncogene. The first data of Aurora-A involvement in cancer regarded the identification of Aurora-A overexpression in primary breast and colon tumour samples. With regard to the predictive role of Aurora-A, it has been shown that its overexpression disrupts the spindle checkpoint activated by paclitaxel (Taxol) or nocodazole treatment, thus inducing the cells to become resistant to these drugs. The development therefore of small molecules with an Aurora-A inhibition function may make it possible to reduce or block the oncogenic activity of Aurora-A and in addition may improve the survival of oncological patients showing resistance to paclitaxel or nocodazole treatment. Three novel Aurora kinase inhibitors have recently been described--Hesperadin, ZM447439 and VX-680. All these three drugs have been designed to target the ATP-binding site of Aurora kinase, so they inhibit all three Aurora kinase family members showing a similar phenotype when tested in cell-based assays. Among these three different molecules, VX-680 has shown promising results in in vitro and in vivo studies. In conclusion, it is clear that we are entering a new era in anti-mitotic therapy with the identification and now clinical translation of new targets in mitosis beyond tubulin but many questions remain with regard to Aurora function

    Systematization of tensor mesons and the determination of the 2++2^{++} glueball

    Full text link
    It is shown that new data on the (JPC=2++)(J^{PC}=2^{++})-resonances in the mass range M∼1700−2400M\sim1700-2400 MeV support the linearity of the (n,M2)(n,M^2)-trajectories, where nn is the radial quantum number of quark--antiquark state. In this way all vacancies for the isoscalar tensor qqˉq\bar q-mesons in the range up to 2450 MeV are filled in. This allows one to fix the broad f2f_2-state with M=2000±30M=2000\pm30 MeV and Γ=530±40\Gamma=530\pm40 MeV as the lowest tensor glueball. PACS numbers: 14.40.-n, 12.38.-t, 12.39.-MkComment: 10 pages, 1 figur
    • …
    corecore