12,911 research outputs found

    Thinking culturally about place

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    This paper explains the bases for an alternative approach to place branding and marketing, based on the disciplines of Cultural Mapping and Cultural Planning. After an introduction of key cultural mapping and planning concepts and issues, the paper discusses some innovative practical examples of culturally sensitive place branding and marketing from Sweden and the UK, and concludes by outlining some components of a possible future agenda for action

    Imprints of gravitational lensing in the Planck CMB data at the location of WISExSCOS galaxies

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    We detect weak gravitational lensing of the cosmic microwave background (CMB) at the location of the WISExSCOS (WxS) galaxies using the publicly available Planck lensing convergence map. By stacking the lensing convergence map at the position of 12.4 million galaxies in the redshift range 0.1z0.3450.1\le z \le 0.345, we find the average mass of the galaxies to be M200crit_{200_{\rm crit}} = 6.25 ±\pm 0.6 ×1012 M\times 10^{12}\ M_{\odot}. The null hypothesis of no-lensing is rejected at a significance of 17σ17\sigma. We split the galaxy sample into three redshift slices each containing \sim4.1 million objects and obtain lensing masses in each slice of 4.18 ±\pm 0.8, 6.93 ±\pm 0.9, and 18.84 ±\pm 1.2 \times\ 10^{12}\ \mbox{M}_{\odot}. Our results suggest a redshift evolution of the galaxy sample masses but this apparent increase might be due to the preferential selection of intrinsically luminous sources at high redshifts. The recovered mass of the stacked sample is reduced by 28% when we remove the galaxies in the vicinity of galaxy clusters with mass M200crit_{200_{\rm crit}} = 2 \times 10^{14}\ \mbox{M}_{\odot}. We forecast that upcoming CMB surveys can achieve 5% galaxy mass constraints over sets of 12.4 million galaxies with M200crit_{200_{\rm crit}} = 1×1012 M1 \times 10^{12}\ M_{\odot} at z=1z=1.Comment: 7 pages, 2 figures, 2 tables: updates: correlations between z-bins included: accepted for publication in PR

    Constraining gravity at large scales with the 2MASS Photometric Redshift catalogue and Planck lensing

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    We present a new measurement of structure growth at z0.08z \simeq 0.08 obtained by correlating the cosmic microwave background (CMB) lensing potential map from the \textit{Planck} satellite with the angular distribution of the 2MASS Photometric Redshift galaxies. After testing for, and finding no evidence for systematic effects, we calculate the angular auto- and cross-power spectra. We combine these spectra to estimate the amplitude of structure growth using the bias-independent DGD_G estimator introduced by Giannantonio et al. 2016. We find that the relative amplitude of DGD_G with respect to the predictions based on \textit{Planck} cosmology is AD(z=0.08)=1.00±0.21A_D(z=0.08) = 1.00 \pm 0.21, fully consistent with the expectations for the standard cosmological model. Considering statistical errors only, we forecast that a joint analysis between an LSST-like photometric galaxy sample and lensing maps from upcoming ground-based CMB surveys like the Simons Observatory and CMB-S4 can yield sub-percent constraints on the growth history and differentiate between different models of cosmic acceleration.Comment: 14 pages, 8 figures, 1 table, updated to match published version on Ap

    Rotating Globular Clusters

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    Internal rotation is considered to play a major role in the dynamics of some globular clusters. However, in only few cases it has been studied by quantitative application of realistic and physically justified global models. Here we present a dynamical analysis of the photometry and three-dimensional kinematics of omega Cen, 47 Tuc, and M15, by means of a recently introduced family of self-consistent axisymmetric rotating models. The three clusters, characterized by different relaxation conditions, show evidence of differential rotation and deviations from sphericity. The combination of line-of-sight velocities and proper motions allows us to determine their internal dynamics, predict their morphology, and estimate their dynamical distance. The well-relaxed cluster 47 Tuc is very well interpreted by our model; internal rotation is found to explain the observed morphology. For M15, we provide a global model in good agreement with the data, including the central behavior of the rotation profile and the shape of the ellipticity profile. For the partially relaxed cluster omega Cen, the selected model reproduces the complex three-dimensional kinematics; in particular the observed anisotropy profile, characterized by a transition from isotropy, to weakly-radial anisotropy, and then to tangential anisotropy in the outer parts. The discrepancy found for the steep central gradient in the observed line-of-sight velocity dispersion profile and for the ellipticity profile is ascribed to the condition of only partial relaxation of this cluster and the interplay between rotation and radial anisotropy.Comment: 19 pages, 14 figures, accepted for publication in the Astrophysical Journa

    Technical Note: REFIR-PAD level 1 data analysis and performance characterization

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    The outgoing long-wave radiation from the Earth's atmosphere in the far infrared spectral region is mostly unexplored, while is well recognized that the water vapour contribution to greenhouse trapping is dominant in this region. The Radiation Explorer in the Far InfraRed (REFIR) study has proven the feasibility of a space-borne Fourier transform spectrometer able to perform the measurement in the 100–1100 cm<sup>−1</sup> range with a resolution of 0.5 cm<sup>−1</sup>. Following this work a prototype of the spectrometer named REFIR-PAD (Prototype for Applications and Development) has been developed to observe the atmospheric radiance from both ground-based sites and from stratospheric balloon platforms. In this work we describe the REFIR-PAD level 1 data analysis procedure, that, starting from raw instrumental data produces the calibrated atmospheric spectral radiance. Performances of the procedure are also described

    Tradizione manoscritta e citazioni epigrafiche di Ovidio. Una nota su Trist. 1, 3, 25 e Pont. 1, 2, 111 alla luce di alcuni confronti epigrafici

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    This paper discusses two verses of Ovid’s Tristia (1, 3, 25) and Epistulae ex Ponto (1, 2, 111), for which the manuscript tradition is discordant. These lines are quoted in three epigraphic documents: CLE 1339 = ICVR, I 3903, CLE 1979 = ICVR, VIII 23529 and CLE 1988 = CIL, VI 37965. How reliable are the quotations in the Latin inscriptions? Do they help to reassess the Ovidian text? The main purpose of this study is to answer such questions, with respect to these particular cases

    Auto-oscillation threshold, narrow spectral lines, and line jitter in spin-torque oscillators based on MgO magnetic tunnel junctions

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    We demonstrate spin torque induced auto-oscillation in MgO-based magnetic tunnel junctions. At the generation threshold, we observe a strong line narrowing down to 6 MHz at 300K and a dramatic increase in oscillator power, yielding spectrally pure oscillations free of flicker noise. Setting the synthetic antiferromagnet into autooscillation requires the same current polarity as the one needed to switch the free layer magnetization. The induced auto-oscillations are observed even at zero applied field, which is believed to be the acoustic mode of the synthetic antiferromagnet. While the phase coherence of the auto-oscillation is of the order of microseconds, the power autocorrelation time is of the order of milliseconds and can be strongly influenced by the free layer dynamics

    Ocular hypertension in myopia: analysis of contrast sensitivity

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    Purpose: we evaluated the evolution of contrast sensitivity reduction in patients affected by ocular hypertension and glaucoma, with low to moderate myopia. We also evaluated the relationship between contrast sensitivity and mean deviation of visual field. Material and methods: 158 patients (316 eyes), aged between 38 and 57 years old, were enrolled and divided into 4 groups: emmetropes, myopes, myopes with ocular hypertension (IOP≥21 ±2 mmHg), myopes with glaucoma. All patients underwent anamnestic and complete eye evaluation, tonometric curves with Goldmann’s applanation tonometer, cup/disc ratio evaluation, gonioscopy by Goldmann’s three-mirrors lens, automated perimetry (Humphrey 30-2 full-threshold test) and contrast sensitivity evaluation by Pelli-Robson charts. A contrast sensitivity under 1,8 Logarithm of the Minimum Angle of Resolution (LogMAR) was considered abnormal. Results: contrast sensitivity was reduced in the group of myopes with ocular hypertension (1,788 LogMAR) and in the group of myopes with glaucoma (1,743 LogMAR), while it was preserved in the group of myopes (2,069 LogMAR) and in the group of emmetropes (1,990 LogMAR). We also found a strong correlation between contrast sensitivity reduction and mean deviation of visual fields in myopes with glaucoma (coefficient relation = 0.86) and in myopes with ocular hypertension (coefficient relation = 0.78). Conclusions: the contrast sensitivity assessment performed by the Pelli-Robson test should be performed in all patients with middle-grade myopia, ocular hypertension and optic disc suspected for glaucoma, as it may be useful in the early diagnosis of the disease. Introduction Contrast can be defined as the ability of the eye to discriminate differences in luminance between the stimulus and the background. The sensitivity to contrast is represented by the inverse of the minimal contrast necessary to make an object visible; the lower the contrast the greater the sensitivity, and the other way around. Contrast sensitivity is a fundamental aspect of vision together with visual acuity: the latter defines the smallest spatial detail that the subject manages to discriminate under optimal conditions, but it only provides information about the size of the stimulus that the eye is capable to perceive; instead, the evaluation of contrast sensitivity provides information not obtainable with only the measurement of visual acuity, as it establishes the minimum difference in luminance that must be present between the stimulus and its background so that the retina is adequately stimulated to perceive the stimulus itself. The clinical methods of examining contrast sensitivity (lattices, luminance gradients, variable-contrast optotypic tables and lowcontrast optotypic tables) relate the two parameters on which the ability to distinctly perceive an object depends, namely the different luminance degree of the two adjacent areas and the spatial frequency, which is linked to the size of the object. The measurement of contrast sensitivity becomes valuable in the diagnosis and follow up of some important eye conditions such as glaucoma. Studies show that contrast sensitivity can be related to data obtained with the visual perimetry, especially with the perimetric damage of the central area and of the optic nerve head

    Educação ambiental e o trabalho com valores nas reflexões de professores participantes de um curso de formação continuada

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    A educação ambiental tem sido considerada de fundamental importância para superação da crise ambiental contemporânea, esta resultante de um complexo de relações envolvendo o atual modelo econômico, a ciência e a tecnologia. Nessa proposta destaca-se sua dimensão valorativa, essencial para um trabalho mais abrangente. A pesquisa apresentada, desenvolvida a partir de uma abordagem qualitativa, analisa neste trabalho as reflexões de um grupo de professores da rede pública de ensino de um estado brasileiro, participantes de um curso de formação continuada sobre a educação ambiental e o trabalho com valores. A análise dos dados coletados através da filmagem dos encontros indica algumas das dificuldades encontradas pelos professores ao lidar com o tema, aspectos que devem ser considerados nos programas de formação docente relativos a essa temática
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