New radio halos and relics in clusters of galaxies

We present here new images of relics and halo sources in rich cluster of galaxies and the correlation between the halo radio surface brightness versus the cluster bolometric X-ray luminosity.Comment: 2 pages, 4 figures. To appear in the Proceedings of the International Conference: "The Origin and Evolution of Cosmic Magnetism"; Bologna 29 August - 2 September 2005; eds R. Beck, G. Brunetti, L. Feretti, and B. Gaensler (Astronomische Nachrichten, 2006

Stream dynamics between 1 AU and 2 AU: A detailed comparison of observations and theory

A radial alignment of three solar wind stream structures observed by IMP-7 and -8 (at 1.0 AU) and Voyager 1 and 2 (in the range 1.4 to 1.8 AU) in late 1977 is presented. It is demonstrated that several important aspects of the observed dynamical evolution can be both qualitatively and quantitatively described with a single-fluid 2-D MHD numerical model of quasi-steady corotating flow, including accurate prediction of: (1) the formation of a corotating shock pair at 1.75 AU in the case of a simple, quasi-steady stream; (2) the coalescence of the thermodynamic and magnetic structures associated with the compression regions of two neighboring, interacting, corotating streams; and (3) the dynamical destruction of a small (i.e., low velocity-amplitude, short spatial-scale) stream by its overtaking of a slower moving, high-density region associated with a preceding transient flow. The evolution of these flow systems is discussed in terms of the concepts of filtering and entrainment

Diffuse radio emission in the complex merging galaxy cluster Abell 2069

Galaxy clusters with signs for a recent merger show in many cases extended diffuse radio features. This emission originates from relativistic electrons which suffer synchrotron losses due to the intra-cluster magnetic field. The mechanisms of the particle acceleration and the properties of the magnetic field are still poorly understood. We search for diffuse radio emission in galaxy clusters. Here, we study the complex galaxy cluster Abell 2069, for which X-ray observations indicate a recent merger. We investigate the cluster's radio continuum emission by deep Westerbork Synthesis Radio Telescope (WSRT) observations at 346 MHz and a Giant Metrewave Radio Telescope (GMRT) observation at 322 MHz. We find an extended diffuse radio feature roughly coinciding with the main component of the cluster. We classify this emission as a radio halo and estimate its lower limit flux density to 25 +/- 9 mJy. Moreover, we find a second extended diffuse source located at the cluster's companion and estimate its flux density to 15 +/- 2 mJy. We speculate that this is a small halo or a mini-halo. If true, this cluster is the first example of a double-halo in a single galaxy cluster.Comment: 6 pages, 3 figures, accepted for publication in A&

Contributions to the Fourth Solar Wind Conference

Recent results in interplanetary physics are examined. These include observations of shock waves and post-shock magnetic fields made by Voyager 1, 2; observations of the electron temperature as a function of distance between 1.36 AU and 2.25 AU; and observations of the structure of sector boundaries observed by Helios 1. A theory of electron energy transport in the collisionless solar wind is presented, and compared with observations. Alfven waves and Alvenic fluctuations in the solar wind are also discussed

IL-17 polarization of MAIT cells is derived from the activation of two different pathways

MAIT cells are expanded in salivary glands of patients with Sjogren's syndrome and are IL-17 polarized. IL-7 and IL-23 induce IL-17 production activating two different pathways: IL-7 stimulation induces in fact a significant STAT3 and HIF1alpha upregulation, conversely, IL-23 stimulation significantly induces RORc overexpression in MAIT cells of patients with Sjogren's syndrome

Assessment of urinary mutagens presence in a population of non smokers

The paper presents the early results of a study involving a group of 312 non smoking and not professionally exposed subjects (144 males and 168 females) in order to evaluate the probable presence of urinary mutagens possibly derived from aspecific exposures. Urine samples were assayed by the Ames test on the YG1024 Salmonella typhimurium strain in the presence of S9 mix with plate incorporation method with preincubation. At the moment of sample collection, the subjects were invited to fill a questionnaire on their main characteristics and lifestyle. On the basis of laboratory data analysis, it emerged that, on 288 samples with a valuable mutagenic activity, 20 urinary extracts (8 of which were males and 12 were females) showed mutagenicity levels twice as much as spontaneous revertants. Diet and indoor exposure to passive smoking, fireplace and cooking fume exposure seemed to play a major role among the lifestyle behaviours investigated in generating positive mutagenic response with a statistically significant difference between positive and negative samples induction (Chi square, P = 0.0057 and P = 0.0168 respectively). After correction of induced revertants by means of creatinine excretion determination, it appeared that females, who had the higher mean urinary mutagenic activity, showed a mutagenicity level twice as much as men (364 ± 491 revertants/mmole creatinine for males against 605 ± 868 revertants/mmole creatinine in females, Mann-Whitney U-test, z = -3.97, P inf. 0.0001) possibly in consequence of their greater cooking fumes exposure. The study, that carefully evaluated the characteristics of involved subjects, reveals the presence, even though modest, of mutagens in urine of an apparently not significantly exposed population. In addition, standardization of method leads to suppose little feasible a confounding influence of considered features. Moreover, it would be therefore rather interesting to study the effect of low exposure time persistence

Salvage treatment with ganciclovir in a splenectomized, polytransfused patient affected by systemic inflammatory response syndrome

A 23-year-old man was admitted to hospital with a 12-day history of daily fever. A clinical history revealed that 10 months previously, the patient had been splenectomized and polytransfused for a severe blunt trauma. On admission, laboratory data revealed significant leukocytosis (33,230/ul). The patient's general clinical conditions rapidly worsened into a severe systemic inflammatory response syndrome in four days. After 10 days of broad-spectrum antibiotic treatment, the temperature curve was unmodified and severe leukocytosis persisted (44,300 ul) with absolute lymphocytosis. Laboratory tests ruled out hematological diseases, pneumonia, abscesses and endocarditis. In the light of IgM positivity for CMV (unconfirmed by PCR) and with the support of a PubMed search, we commenced a salvage treatment with intravenous ganciclovir, suspecting a viral infection or reactivation. After two days of therapy, an immediate defervescence was observed with a remarkable clinical improvement. After 10 days, the clinical syndrome had been completely resolved and the patient was discharged in good, general clinical health

The social return on investment (SROI) of four microfinance projects

The paper develops an SROI (Social Return on Investment) analysis of four microfinance institutions (MFIs) located in Spain, Italy and Bosnia-Herzegovina. This work is part of the MeMI Project (\u201cMeasuring Microfinance Impact in the EU. Policy recommendations for Financial and Social Inclusion\u201d) funded by the EIBURS. It is an attempt to translate microcredit outcome indicators into a social return, quantified in monetary terms. After preliminary focus group analyses and staff interviews, data on outcomes of selected microcredit lines have been collected through a questionnaire administered to the borrowers. By comparing the monetary value of these outcomes (translated into an estimated impact) with the amount of related investment, we find that SROI is greater than 2 for all the credit lines analysed, meaning that every euro invested in microcredit generates at least 2 euros of social return. We also find SROI ranging between 2.33 and 6.97, mirroring the differences between MFIs in terms of target, operating model and country-level financial environment. Although the analysis is conducted on a limited number of cases and SROI calculation can be sharpened, it shows how different factors and outcomes drive the social return generated by microcredit

The MeerKAT Fornax Survey

We present the science case and observations plan of the MeerKAT Fornax Survey, an HI and radio continuum survey of the Fornax galaxy cluster to be carried out with the SKA precursor MeerKAT. Fornax is the second most massive cluster within 20 Mpc and the largest nearby cluster in the southern hemisphere. Its low X-ray luminosity makes it representative of the environment where most galaxies live and where substantial galaxy evolution takes place. Fornax's ongoing growth makes it an excellent laboratory for studying the assembly of clusters, the physics of gas accretion and stripping in galaxies falling in the cluster, and the connection between these processes and the neutral medium in the cosmic web. We will observe a region of 12 deg$^2$ reaching a projected distance of 1.5 Mpc from the cluster centre. This will cover a wide range of environment density out to the outskirts of the cluster, where gas-rich in-falling groups are found. We will: study the HI morphology of resolved galaxies down to a column density of a few times 1e+19 cm$^{-2}$ at a resolution of 1 kpc; measure the slope of the HI mass function down to M(HI) 5e+5 M(sun); and attempt to detect HI in the cosmic web reaching a column density of 1e+18 cm$^{-2}$ at a resolution of 10 kpc.Comment: Proceedings of Science, "MeerKAT Science: On the Pathway to the SKA", Stellenbosch, 25-27 May 201

Radio spectral study of the cluster of galaxies Abell 2255

Spectral index studies of halos, relics, and radio galaxies provide useful information on their origin and connection with merger processes. We present WSRT multi-wavelength observations of the galaxy cluster Abell 2255 at 25 cm, 85 cm, and 2 m. The spectral index images allowed us to study the integrated spectrum of halo and relic and to investigate the physical properties of the Beaver head-tail radio galaxy belonging to the cluster. In the radio halo, the spectral index is steeper at the center and flatter at the locations of the radio filaments, clearly detected at 25 cm. In the relics, the spectral index flattens, moving away from the cluster center. For the Beaver radio galaxy, the spectrum severely steepens from the head towards the end of the tail, because of the energy losses suffered by the relativistic particles. In the 2 m map, which is the first high-sensitivity image presented in the literature at such a long wavelength, a new Mpc-size emission region is detected between the known radio halo and the NW relic. Not detecting this feature in the more sensitive 85 cm observations implies that it must have a very steep spectrum (alpha <= -2.6). The observational properties of the radio halo suggest that either we are looking at a superposition of different structures (filaments in the foreground plus real halo in the background) seen in projection across the cluster center or that the halo is intrinsically peculiar. The newly detected extended region to the NW of the halo could be considered as an asymmetric extension of the halo itself. However, since radio halos are known in the literature as structures showing a regular morphology, the new feature could represent the first example of steep Mpc-size diffuse structures (MDS), detected around clusters at very low frequencies.Comment: 23 pages, 18 figures. A&A, in pres