A radio continuum survey of the southern sky at 1420 MHz. Observations and data reduction

We describe the equipment, observational method and reduction procedure of an absolutely calibrated radio continuum survey of the South Celestial Hemisphere at a frequency of 1420 MHz. These observations cover the area 0h < R.A. < 24h for declinations less than -10 degree. The sensitivity is about 50 mK T_B (full beam brightness) and the angular resolution (HPBW) is 35.4', which matches the existing northern sky survey at the same frequency.Comment: 9 pages with 9 figures, A&A, in pres

Does Social Presence or the Potential for Interaction reduce Social Gaze in Online Social Scenarios? Introducing the "Live Lab" paradigm.

Research has shown that people’s gaze is biased away from faces in the real-world but towards them when they are viewed onscreen. Non-equivalent stimulus conditions may have represented a confound in this research however, as participants viewed onscreen stimuli as pre-recordings where interaction was not possible, compared to real-world stimuli which were viewed in real-time where interaction was possible. We assessed the independent contributions of online social presence and ability for interaction on social gaze by developing the “live lab” paradigm. Participants in three groups (N = 132) viewed a confederate either as a) a live webcam stream where interaction was not possible (one-way), b) a live webcam stream where an interaction was possible (two-way) or c) as a prerecording. Potential for interaction, rather than online social presence, was the primary influence on gaze behaviour: Participants in the pre-recorded and one-way conditions looked more to the face than those in the two-way condition, particularly when the confederate made “eye contact”. Fixation durations to the face were shorter when the scene was viewed live, particularly during a bid for eye contact Our findings support the dual function of gaze, but suggest that online social presence alone is not sufficient to activate social norms of civil inattention. Implications for the reinterpretation of previous research are discussed

A comparison of sacral neuromodulation vs. transvaginal electrical stimulation for the treatment of refractory overactive bladder: The impact on quality of life, body image, sexual function, and emotional well-being

Overactive bladder syndrome (OAB) is defined by the presence of urinary urgency, with or without urge incontinence, usually accompanied by an increase in urinary frequency and nocturia in the absence of urinary tract infections (UTI) or other diseases. The overall prevalence of OAB symptoms in the female population is reported to be 16.6% and increases with advancing age and menopause. The aetiology of OAB is not fully understood and is likely to affect a heterogeneous population of patients due to changes to their central and peripheral nervous systems. Although OAB is frequently associated with female sexual dysfunction (FSD), its real impact on sexual function in women has been evaluated only in a few studies. The first line of treatment for OAB includes behavioural modification and physical therapy, either as monotherapies or in combination. Many patients who have not had success in managing their symptoms with more conservative therapies may decide to resort to third-line treatments for refractory OAB. These treatments include neuromodulation therapies, particularly transvaginal electrical stimulation (TES) and sacral neuromodulation (SN). The aim of this short commentary is to provide an overview of the effectiveness of these treatments and of their impact on quality of life, body image, sexual function, and emotional well-being

Bouncing and emergent cosmologies from Arnowitt-Deser-Misner RG flows

Asymptotically safe gravity provides a framework for the description of gravity from the trans-Planckian regime to cosmological scales. According to this scenario, the cosmological constant and Newton’s coupling are functions of the energy scale whose evolution is dictated by the renormalization group (RG) equations. The formulation of the RG equations on foliated spacetimes, based on the Arnowitt-Deser-Misner (ADM) formalism, furnishes a natural way to construct the RG energy scale from the spectrum of the Laplacian operator on the spatial slices. Combining this idea with an RG improvement procedure, in this work we study quantum gravitational corrections to the Einstein-Hilbert action on Friedmann-Lemaître-Robertson-Walker backgrounds. The resulting quantum-corrected Friedmann equations can give rise to both bouncing cosmologies and emergent Universe solutions. Our bouncing models do not require the presence of exotic matter and emergent Universe solutions can be constructed for any allowed topology of the spatial slices

ARCADE 2 Observations of Galactic Radio Emission

We use absolutely calibrated data from the ARCADE 2 flight in July 2006 to model Galactic emission at frequencies 3, 8, and 10 GHz. The spatial structure in the data is consistent with a superposition of free-free and synchrotron emission. Emission with spatial morphology traced by the Haslam 408 MHz survey has spectral index beta_synch = -2.5 +/- 0.1, with free-free emission contributing 0.10 +/- 0.01 of the total Galactic plane emission in the lowest ARCADE 2 band at 3.15 GHz. We estimate the total Galactic emission toward the polar caps using either a simple plane-parallel model with csc|b| dependence or a model of high-latitude radio emission traced by the COBE/FIRAS map of CII emission. Both methods are consistent with a single power-law over the frequency range 22 MHz to 10 GHz, with total Galactic emission towards the north polar cap T_Gal = 0.498 +/- 0.028 K and spectral index beta = -2.55 +/- 0.03 at reference frequency 1 GHz. The well calibrated ARCADE 2 maps provide a new test for spinning dust emission, based on the integrated intensity of emission from the Galactic plane instead of cross-correlations with the thermal dust spatial morphology. The Galactic plane intensity measured by ARCADE 2 is fainter than predicted by models without spinning dust, and is consistent with spinning dust contributing 0.4 +/- 0.1 of the Galactic plane emission at 22 GHz.Comment: 10 poges, 9 figures. Submitted to The Astrophysical Journa

A polarized synchrotron template for CMBP experiments after WMAP data

We build template maps for the polarized Galactic--synchrotron emission on large angular scales (FWHM =~7$^\circ$), in the 20-90 GHz microwave range, by using WMAP data. The method, presented in a recent work, requires a synchrotron total intensity survey and the {\it polarization horizon} to model the polarized intensity and a starlight polarization map to model polarization angles. The basic template is obtained directly at 23 GHz with about 94% sky--coverage by using the synchrotron map released by the WMAP team. Extrapolations to 32, 60 and 90 GHz are performed by computing a synchrotron spectral index map, which strongly reduces previous uncertainties in passing from low (1.4 GHz) to microwave frequencies. Differing from low frequency data, none of our templates presents relevant structures out of the Galactic Plane. Our map at 90 GHz suggests that the synchrotron emission at high Galactic latitudes is low enough to allow a robust detection of the $E$--mode component of the cosmological signal on large--scale, even in models with low--reionization ($\tau = 0.05$). Detection of the weaker $B$--mode on the largest scales ($\ell < 10$) might be jeopardized unless the value $\tau = 0.17$ found by WMAP is confirmed, and $T/S > 0.1$. For lower levels of the gravitational--wave background the $B$--mode seems to be accessible only at the $\ell \sim 100$ peak and in selected low--synchrotron emission areas.Comment: 13 pages, 14 figures, accepted for pubblications by MNRAS. For a version with full resolution color figures see http://sp0rt.bo.iasf.cnr.it:8080/Docs/Public/papers.ph

Advanced modelling of the Planck-LFI radiometers

The Low Frequency Instrument (LFI) is a radiometer array covering the 30-70 GHz spectral range on-board the ESA Planck satellite, launched on May 14th, 2009 to observe the cosmic microwave background (CMB) with unprecedented precision. In this paper we describe the development and validation of a software model of the LFI pseudo-correlation receivers which enables to reproduce and predict all the main system parameters of interest as measured at each of the 44 LFI detectors. These include system total gain, noise temperature, band-pass response, non-linear response. The LFI Advanced RF Model (LARFM) has been constructed by using commercial software tools and data of each radiometer component as measured at single unit level. The LARFM has been successfully used to reproduce the LFI behavior observed during the LFI ground-test campaign. The model is an essential element in the database of LFI data processing center and will be available for any detailed study of radiometer behaviour during the survey.Comment: 21 pages, 15 figures, this paper is part of the Prelaunch status LFI papers published on JINST: http://www.iop.org/EJ/journal/-page=extra.proc5/jins

The 2.3 GHz continuum survey of the GEM project

We present a partial-sky survey of the radio continuum at 2.3 GHz within the scope of the Galactic Emission Mapping (GEM) project, an observational program conceived and developed to reveal the large-scale properties of Galactic synchrotron radiation through a set of self-consistent surveys of the radio continuum between 408 MHz and 10 GHz. The GEM experiment uses a portable and double-shielded 5.5-m radiotelescope in altazimuthal configuration to map 60-degree-wide declination bands from different observational sites by circularly scanning the sky at zenithal angles of 30 deg from a constantly rotating platform. The observations were accomplished with a total power receiver, whose front-end High Electron Mobility Transistor (HEMT) amplifier was matched directly to a cylindrical horn at the prime focus of the parabolic reflector. The Moon was used to calibrate the antenna temperature scale and the preparation of the map required direct subtraction and destriping algorithms to remove ground contamination as the most significant source of systematic error. We used 484 hours of total intensity observations from two locations in Colombia and Brazil to yield 66% sky coverage from DEC = -51.73 deg to DEC = +34.78 deg. The zero-level uncertainty of the combined survey is 103 mK with a temperature scale error of 5% after direct correlation with the Rhodes/HartRAO survey at 2326 MHz on a T-T plot. The sky brightness distribution into regions of low and high emission in the GEM survey is consistent with the appearance of a transition region as seen in the Haslam 408 MHz and WMAP K-band surveys. Preliminary results also show that the temperature spectral index between 408 MHz and the 2.3 GHz band of the GEM survey has a weak spatial correlation with these regions; but it steepens significantly from high to low emission regions with respect to the WMAP K-band survey.Comment: 20 pages, 21 figures, 6 tables. Extensively revised and enlarged version accepted for publication in Astronomy & Astrophysics. Smaller figure

Foreground removal from CMB temperature maps using an MLP neural network

One of the main obstacles in extracting the Cosmic Microwave Background (CMB) signal from observations in the mm-submm range is the foreground contamination by emission from galactic components: mainly synchrotron, free-free and thermal dust emission. Due to the statistical nature of the intrinsic CMB signal it is essential to minimize the systematic errors in the CMB temperature determinations. Following the available knowledge of the spectral behavior of the galactic foregrounds simple, power law-like spectra have been assumed. The feasibility of using a simple neural network for extracting the CMB temperature signal from the combined CMB and foreground signals has been investigated. As a specific example, we have analysed simulated data, like that expected from the ESA Planck Surveyor mission. A simple multilayer perceptron neural network with 2 hidden layers can provide temperature estimates, over more than 80 percent of the sky, that are to a high degree uncorrelated with the foreground signals. A single network will be able to cover the dynamic range of the Planck noise level over the entire sky.Comment: Accepted for publication in Astrophysics and Space Scienc

De-contamination of cosmological 21-cm maps

We present a method for extracting the expected cosmological 21-cm signal from the epoch of reionization, taking into account contaminating radiations and random instrumental noise. The method is based on the maximum a-posteriori probability (MAP) formalism and employs the coherence of the contaminating radiation along the line-of-sight and the three-dimensional correlations of the cosmological signal. We test the method using a detailed and comprehensive modeling of the cosmological 21-cm signal and the contaminating radiation. The signal is obtained using a high resolution N-body simulation where the gas is assumed to trace the dark matter and is reionized by stellar radiation computed from semi-analytic galaxy formation recipes. We model contaminations to the cosmological signal from synchrotron and free-free galactic foregrounds and extragalactic sources including active galactic nuclei, radio haloes and relics, synchrotron and free-free emission from star forming galaxies, and free-free emission from dark matter haloes and the intergalactic medium. We provide tests of the reconstruction method for several rms values of instrumental noise from $\sigma_{N}=1$ to 250 mK. For low instrumental noise, the recovered signal, along individual lines-of-sight, fits the true cosmological signal with a mean rms difference of $d_{rms}\approx 1.7\pm 0.6$ for $\sigma_{N}=1$ mK, and $d_{rms}\approx 4.2\pm 0.4$ for $\sigma_{N}=5$ mK. The one-dimensional power spectrum is nicely reconstructed for all values of $\sigma_{N}$ considered here, while the reconstruction of the two-dimensional power spectrum and the Minkowski functionals is good only for noise levels of the order of few mK.Comment: 19 pages, 17 figures, accepted for publication in MNRA