114 research outputs found

    Redox-active charge carriers of conducting polymers as a tuner of conductivity and its potential window

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    Electric conductivity of conducting polymers has been steadily enhanced towards a level worthy of being called its alias, "synthetic metal". PEDOT:PSS (poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonate)), as a representative conducting polymer, recently reached around 3,000â�...S cm -1, the value to open the possibility to replace transparent conductive oxides. The leading strategy to drive the conductivity increase is solvent annealing in which aqueous solution of PEDOT:PSS is treated with an assistant solvent such as DMSO (dimethyl sulfoxide). In addition to the conductivity enhancement, we found that the potential range in which PEDOT:PSS is conductive is tuned wider into a negative potential direction by the DMSO-annealing. Also, the increase in a redox-active fraction of charge carriers is proposed to be responsible for the enhancement of conductivity in the solvent annealing process.open3

    Comparison of the CBA-H and SF-36 for the screening of the psychological and behavioural variables in chronic dialysis patients

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    The aim of the study was to perform an analysis of the emotional reactions, perception of stressful life and behavioural changes related to Haemodialysis (HD) in order to identify those variables that can improve lifestyle and the adherence to treatment. Some psycho- metric assessment, such as the Cognitive Behavioural Assessment, Hospital Form, (CBA- H) and the Health Survey (SF-36), which provides two indexes: the Physical Component Score (PCS) and the Mental Component Score (MCS), are suitable to assess a patient’s psychological and behavioural style and their health-related quality of life. The study involved 37 Italian out-patients with end-stage renal disease under HD therapy. We calcu- lated the Spearman correlation between variables of CBA-H, SF-36, age and time on HD. We also performed a multivariate linear regression using the CBA-H variables as predictors and PCS and MCS as dependent variables. From the CBA-H, 95% of participants self- reported psychological characteristics comparable to Type A personality, which identifies an anxious, hyperactive and hostile subject. Physical limitations were found to be directly pro- portional to the time on dialysis (rs = -0.42). The condition of perceived stress worsens the state of mental health (rs = -0.68) and general health perception (rs = -0.44). The condition of vital exhaustion correlates both the PCS and the MCS (p<0.01) with possible outcomes of physical and mental illness. The psychological wellbeing of a dialyzed patient could be due to the combination of several factors, including life parameters, the positive perception of psychosocial outcomes, and the perceived quality of life. A multidisciplinary team (neurolo- gists, psychiatrists, psychologists, and nurses) is essential to plan effective psychological and psychotherapeutic interventions to improve a mind-body integration

    H-ATLAS/GAMA: The nature and characteristics of optically red galaxies detected at submillimetre wavelengths

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    We combine Herschel/SPIRE sub-millimeter (submm) observations with existing multi-wavelength data to investigate the characteristics of low redshift, optically red galaxies detected in submm bands. We select a sample of galaxies in the redshift range 0.01≀\leqz≀\leq0.2, having >5σ\sigma detections in the SPIRE 250 micron submm waveband. Sources are then divided into two sub-samples of redred and blueblue galaxies, based on their UV-optical colours. Galaxies in the redred sample account for ≈\approx4.2 per cent of the total number of sources with stellar masses M∗≳_{*}\gtrsim1010^{10} Solar-mass. Following visual classification of the redred galaxies, we find that ≳\gtrsim30 per cent of them are early-type galaxies and ≳\gtrsim40 per cent are spirals. The colour of the redred-spiral galaxies could be the result of their highly inclined orientation and/or a strong contribution of the old stellar population. It is found that irrespective of their morphological types, redred and blueblue sources occupy environments with more or less similar densities (i.e., the ÎŁ5\Sigma_5 parameter). From the analysis of the spectral energy distributions (SEDs) of galaxies in our samples based on MAGPHYS, we find that galaxies in the redred sample (of any morphological type) have dust masses similar to those in the blueblue sample (i.e. normal spiral/star-forming systems). However, in comparison to the redred-spirals and in particular blueblue systems, redred-ellipticals have lower mean dust-to-stellar mass ratios. Besides galaxies in the redred-elliptical sample have much lower mean star-formation/specific-star-formation rates in contrast to their counterparts in the blueblue sample. Our results support a scenario where dust in early-type systems is likely to be of an external origin

    Planck intermediate results. XIX. An overview of the polarized thermal emission from Galactic dust

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    This paper presents an overview of the polarized sky as seen by Planck HFI at 353 GHz, which is the most sensitive Planck channel for dust polarization. We construct and analyse maps of dust polarization fraction and polarization angle at 1° resolution, taking into account noise bias and possible systematic effects. The sensitivity of the Planck HFI polarization measurements allows for the first time a mapping of Galactic dust polarized emission on large scales, including low column density regions. We find that the maximum observed dust polarization fraction is high (pmax = 19.8%), in particular in some regions of moderate hydrogen column density (NH < 2 × 1021 cm-2). The polarization fraction displays a large scatter at NH below a few 1021 cm-2. There is a general decrease in the dust polarization fraction with increasing column density above NH ≃ 1 × 1021 cm-2 and in particular a sharp drop above NH ≃ 1.5 × 1022 cm-2. We characterize the spatial structure of the polarization angle using the angle dispersion function. We find that the polarization angle is ordered over extended areas of several square degrees, separated by filamentary structures of high angle dispersion function. These appear as interfaces where the sky projection of the magnetic field changes abruptly without variations in the column density. The polarization fraction is found to be anti-correlated with the dispersion of polarization angles. These results suggest that, at the resolution of 1°, depolarization is due mainly to fluctuations in the magnetic field orientation along the line of sight, rather than to the loss of grain alignment in shielded regions. We also compare the polarization of thermal dust emission with that of synchrotron measured with Planck, low-frequency radio data, and Faraday rotation measurements toward extragalactic sources. These components bear resemblance along the Galactic plane and in some regions such as the Fan and North Polar Spur regions. The poor match observed in other regions shows, however, that dust, cosmic-ray electrons, and thermal electrons generally sample different parts of the line of sight. Reproduced with permission, © ESO, 201
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