Access to consciousness of briefly presented visual events is modulated by transcranial direct current stimulation of left dorsolateral prefrontal cortex

Adaptive behaviour requires the ability to process goal-relevant events at the expense of irrelevant ones. However, perception of a relevant visual event can transiently preclude access to consciousness of subsequent events — a phenomenon called attentional blink (AB). Here we investigated involvement of the left dorsolateral prefrontal cortex (DLPFC) in conscious access, by using transcranial direct current stimulation (tDCS) to potentiate or reduce neural excitability in the context of an AB task. In a sham-controlled experimental design, we applied between groups anodal or cathodal tDCS over the left DLPFC, and examined whether this stimulation modulated the proportion of stimuli that were consciously reported during the AB period. We found that tDCS over the left DLPFC affected the proportion of consciously perceived target stimuli. Moreover, anodal and cathodal tDCS had opposing effects, and exhibited different temporal patterns. Anodal stimulation attenuated the AB, enhancing conscious report earlier in the AB period. Cathodal stimulation accentuated the AB, reducing conscious report later in the AB period. These findings support the notion that the DLPFC plays a role in facilitating information transition from the unconscious to the conscious stage of processing

DW Cancri in x-rays

We report on the $XMM$-Newton observation of DW Cnc, a candidate intermediate polar candidate whose historical optical light curve shows the existence of periods at $\simeq 38$, $\simeq 86$ and $\simeq 69$ minutes which were interpreted as the white dwarf spin, the orbital and the spin-orbit beat periodicities. By studying the $0.3-10$ keV light curves, we confirm the existence of a period at $\simeq 38$ minutes and find in the OM light curve a signature for a period at $75\pm 21$ minutes which is consistent with both the orbital and spin-orbit beat. { These findings allow us to unveil without any doubt, the nature of DW Cnc as an accreting intermediate polar. The EPIC and RGS source spectra were analyzed and a best fit model, consisting of a multi-temperature plasma, was found. The maximum temperature found when fitting the data is $kT_{max}\simeq 31$ keV which can be interpreted as an upper limit to the temperature of the shock.Comment: 2019. Accepted for publication on MNRAS. 5 figures, 1 table. Updated as, by mistake, an author affiliation was missing from the lis

INTEGRATING OPTICAL AND RADAR IMAGERY TO ENHANCE RIVER DROUGHT MONITORING

Drought events are growingly affecting European and Italian territories, hampering local environments and biodiversity, such as the ones relying on rivers for their subsistence. Monitoring of rivers is becoming an important issue to face drought crisis and may be exploited with different tools. Among the most commons, satellite imagery is exploited to map water coverage, basing on optical or radar sources. This work proposes a combination of the two sensors to overcome possible limitations of the single dataset exploitation, reaching a reliable result. The methodology is applied to a stretch of Po River in Lombardy region (Italy). Through Google Earth Engine platform, optical satellite Sentinel-2 and radar satellite Sentinel-1 data are processed. The combination of the radar data and of the optical spectral indices is carried out through a pixel-based supervised classification, with a Random Forest classifier. Maps of water coverage are obtained, numerical outcomes of water surface evaluation are recorded and validated by the mean of reference hydrometric data. A multitemporal analysis is then reported, aiming to prove the efficiency of the procedure. All iterations show reliable accuracies and correlation among water surface estimation and water table measurements in two sections of interest. In perspective, the proposed methodology will be implemented in tools for supporting drought monitoring to be integrated in environmental public administration policies

A systematic review of genetic polymorphisms associated with binge eating disorder

The genetic polymorphisms involved in the physiopathology of binge eating disorder (BED) are currently unclear. This systematic review aims to highlight and summarize the research on polymorphisms that is conducted in the BED. We looked for observational studies where there was a genetic comparison between adults with BED, in some cases also with obesity or overweight, and healthy controls or obesity/overweight without BED. Our protocol was written using PRISMA. It is registered at PROSPERO (identification: CRD42020198645). To identify potentially relevant documents, the following bibliographic databases were searched without a time limit, but until September 2020: PubMed, PsycINFO, Scopus, and Web of Science. In total, 21 articles were included in the qualitative analysis of the systematic review, as they met the eligibility criteria. Within the selected studies, 41 polymorphisms of 17 genes were assessed. Overall, this systematic review provides a list of potentially useful genetic polymorphisms involved in BED: 5-HTTLPR (5-HTT), Taq1A (ANKK1/DRD2), A118G (OPRM1), C957T (DRD2), rs2283265 (DRD2), Val158Met (COMT), rs6198 (GR), Val103Ile (MC4R), Ile251Leu (MC4R), rs6265 (BNDF), and Leu72Met (GHRL). It is important to emphasize that Taq1A is the polymorphism that showed, in two different research groups, the most significant association with BED. The remaining polymorphisms need further evidence to be confirmed

Correcting the extended-source calibration for the <i>Herschel</i>-SPIRE Fourier-transform spectrometer

We describe an update to the Herschel-Spectral and Photometric Imaging Receiver (SPIRE) Fourier-transform spectrometer (FTS) calibration for extended sources, which incorporates a correction for the frequency-dependent far-field feedhorn efficiency, ηff. This significant correction affects all FTS extended-source calibrated spectra in sparse or mapping mode, regardless of the spectral resolution. Line fluxes and continuum levels are underestimated by factors of 1.3–2 in thespectrometer long wavelength band (447–1018 GHz; 671–294 μm) and 1.4–1.5 in the spectrometer short wavelength band (944–1568 GHz; 318–191 μm). The correction was implemented in the FTS pipeline version 14.1 and has also been described in the SPIRE Handbook since 2017 February. Studies based on extended-source calibrated spectra produced prior to this pipeline version should be critically reconsidered using the current products available in the Herschel Science Archive. Once the extended-source calibrated spectra are corrected for ηff, the synthetic photometry and the broad-band intensities from SPIRE photometer maps agree within 2–4 per cent – similar levels to the comparison of point-source calibrated spectra and photometry from point-source calibrated maps. The two calibration schemes for the FTS are now self-consistent: the conversion between the corrected extended-source and point-source calibrated spectra can be achieved with the beam solid angle and a gain correction that accounts for the diffraction loss

Towards automation of river water surface detection

European rivers are increasingly impacted by frequent and lasting dry periods, with consequences on jeopardized ecosystems and local economies. Tools for monitoring the evolution of such impacts may be profitable exploited by public administration to assess environmental conditions and draw safeguard policies. This work presents the evolution of a methodology which integrates optical and radar imagery, by Copernicus Sentinel constellations, to map river water surfaces. Despite the base methodology being developed as a man-supervised classification, with necessity for the user to manually define training polygons, the proposed advancements will allow the system to automate training sample extraction. The process is based on the realization of binary masks, originated by processing optical and radar imagery with a BMax Otsu algorithm for image segmentation. The masks are then furtherly refined to obtain a reliable set of classified pixels, from which the training samples are extracted. A sensitivity analysis is performed for assessing the optimal amount of pixels to be considered, with respect to the total area of interest. Furthermore, the performances of several Machine Learning supervised classification algorithms are compared, leading to the selection of the best algorithm to be considered for future developments of the methodology

HerMES: Current Cosmic Infrared Background Estimates Can be Explained by Known Galaxies and their Faint Companions at z < 4

We report contributions to cosmic infrared background (CIB) intensities originating from known galaxies and their faint companions at submillimeter wavelengths. Using the publicly-available UltraVISTA catalog, and maps at 250, 350, and 500 {\mu}m from the \emph{Herschel} Multi-tiered Extragalactic Survey (HerMES), we perform a novel measurement that exploits the fact that uncatalogued sources may bias stacked flux densities --- particularly if the resolution of the image is poor --- and intentionally smooth the images before stacking and summing intensities. By smoothing the maps we are capturing the contribution of faint (undetected in K_S ~ 23.4) sources that are physically associated, or correlated, with the detected sources. We find that the cumulative CIB increases with increased smoothing, reaching 9.82 +- 0.78, 5.77 +- 0.43, and 2.32 +- 0.19$\, \rm nW m^{-2} sr^{-1}$ at 250, 350, and 500 {\mu}m at 300 arcsec FWHM. This corresponds to a fraction of the fiducial CIB of 0.94 +- 0.23, 1.07 +- 0.31, and 0.97 +- 0.26 at 250, 350, and 500 {\mu}m, where the uncertainties are dominated by those of the absolute CIB. We then propose, with a simple model combining parametric descriptions for stacked flux densities and stellar mass functions, that emission from galaxies with log(M/Msun) > 8.5 can account for the most of the measured total intensities, and argue against contributions from extended, diffuse emission. Finally, we discuss prospects for future survey instruments to improve the estimates of the absolute CIB levels, and observe any potentially remaining emission at z > 4.Comment: Accepted to ApJL. 6 Pages, 3 figure

Serendipitous detection of an overdensity of Herschel-SPIRE 250 micron sources south of MRC1138-26

We report the serendipitous detection of a significant overdensity of Herschel-SPIRE 250 micron sources in the vicinity of MRC1138-26. We use an adaptive kernel density estimate to quantify the significance, including a comparison with other fields. The overdensity has a size of ~3.5-4' and stands out at ~5sigma with respect to the background estimate. No features with similar significance were found in four extragalactic control fields: GOODS-North, Lockman, COSMOS and UDS. The chance of having a similar overdensity in a field with the same number but randomly distributed sources is less than 2%. The clump is also visible as a low surface brightness feature in the Planck 857 GHz map. We detect 76 sources at 250 micron (with a signal-to-noise ratio greater than 3), in a region of 4' radius; 43 of those are above a flux density limit of 20 mJy. This is a factor of 3.6 in excess over the average in the four control fields, considering only the sources above 20 mJy. We also find an excess in the number counts of sources with 250 micron flux densities between 30 and 40 mJy, compared to deep extragalactic blank-field number counts. Assuming a fixed dust temperature (30 K) and emissivity (beta=1.5) a crude, blackbody-derived redshift distribution, zBB, of the detected sources is significantly different from the distributions in the control fields and exhibits a significant peak at zBB ~ 1.5, although the actual peak redshift is highly degenerate with the temperature. We tentatively suggest, based on zBB and the similar S250/S350 colours of the sources within the peak, that a significant fraction of the sources in the clump may be at a similar redshift. Since the overdensity lies ~7' south of the z=2.16 Spiderweb protocluster MRC1138-26, an intriguing possibility (that is presently unverifiable given the data in hand) is that it lies within the same large-scale structure.(abridged)Comment: 10 pages, 8 figures, accepted for publication in MNRA

Poly-essential and general Hyperelastic World (brane) models

This article provides a unified treatment of an extensive category of non-linear classical field models whereby the universe is represented (perhaps as a brane in a higher dimensional background) in terms of a structure of a mathematically convenient type describable as hyperelastic, for which a complete set of equations of motion is provided just by the energy-momentum conservation law. Particular cases include those of a perfect fluid in quintessential backgrounds of various kinds, as well as models of the elastic solid kind that has been proposed to account for cosmic acceleration. It is shown how an appropriately generalised Hadamard operator can be used to construct a symplectic structure that controles the evolution of small perturbations, and that provides a characteristic equation governing the propagation of weak discontinuities of diverse (extrinsic and extrinsic) kinds. The special case of a poly-essential model - the k-essential analogue of an ordinary polytropic fluid - is examined and shown to be well behaved (like the fluid) only if the pressure to density ratio $w$ is positive.Comment: 16 pages Latex, Contrib. to 10th Peyresq Pysics Meeting, June 2005: Micro and Macro Structures of Spacetim