232 research outputs found

    Characterizing criminal recidivists by means of tests- of cognition

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    Previous investigations providing psychological tests for identifying the adult, habitual criminal have neglected the concrete-abstract facets of cognition. The present study explores the usefulness of the concrete-abstract dimension for such a purpose by means of the Kahn Test of Symbol Arrangement (the K.T.S.A.), and a Symbolization Test for Criminals (the S.T.C.), which was constructed by the author. Two selected groups were employed; an incarcerated 'criminal recidivists' group and a control group of 'non- criminals' from a vocational rehabilitation centre. The groups were matched for social-class and level of education. Controls as a group, however, were significantly older and scored higher on intelligence (p<.0l). Product moment correlations and analysis of co-variance indicated that the performance of both groups on these tests was independent of age and intelligence (measured by the AH4 part II). The results showed that controls scored significantly higher (more abstract responses) than criminals, on both tests. The criminals displayed a typical pattern of more concrete and repetitive types of symbolizations and fewer abstract responses. This has led to the formulation of typical K.T.S.A. and S.T.C. criminal ‘Symbol-Pattern’ which identified correctly 72% and 77% of all participants, respectively (chi-square, p < .001). A combined K.T.S.A + S.T.C. score elicited the best classification (80% correct identifications, chi-square, p < .001).).The results were interpreted in terms of the hypothesis that criminality is associated with an "arrested cognitive (and emotional) development on the decriminalization process", i.e. the process of socialisation. Future refinements of the S.T.C. were also discussed

    Recovering 3D structural properties of galaxies from SDSS-like photometry

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    Because of the 3D nature of galaxies, an algorithm for constructing spatial density distribution models of galaxies on the basis of galaxy images has many advantages over surface density distribution approximations. We present a method for deriving spatial structure and overall parameters of galaxies from images and estimate its accuracy and derived parameter degeneracies on a sample of idealised model galaxies. The test galaxies consist of a disc-like component and a spheroidal component with varying proportions and properties. Both components are assumed to be axially symmetric and coplanar. We simulate these test galaxies as if observed in the SDSS project through ugriz filters, thus gaining a set of realistically imperfect images of galaxies with known intrinsic properties. These artificial SDSS galaxies were thereafter remodelled by approximating the surface brightness distribution with a 2D projection of a bulge+disc spatial distribution model and the restored parameters were compared to the initial ones. Down to the r-band limiting magnitude 18, errors of the restored integral luminosities and colour indices remain within 0.05 mag and errors of the luminosities of individual components within 0.2 mag. Accuracy of the restored bulge-to-disc ratios (B/D) is within 40% in most cases, and becomes worse for galaxies with low B/D, but the general balance between bulges and discs is not shifted systematically. Assuming that the intrinsic disc axial ratio is < 0.3, the inclination angles can be estimated with errors < 5deg for most of the galaxies with B/D < 2 and with errors < 15deg up to B/D = 6. Errors of the recovered sizes of the galactic components are below 10% in most cases. In general, models of disc components are more accurate than models of spheroidal components for geometrical reasons.Comment: 15 pages, 13 figures, accepted for publication in RA

    Modeling the spectrum of V4334 Sgr (Sakurai's Object)

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    Theoretical spectral energy distributions were computed for a grid of hydrogen-deficient and carbon-rich model atmospheres of T(eff) in the range of 5000-6250 K and log g = 1.0 - 0.0 by the technique of opacity sampling, taking into account continuous, molecular band and atomic line absorption. These energy distributions were compared with the spectrum of V4334 Sgr (Sakurai's object) of April, 1997 in the wavelength interval 300-1000 nm. We show that (1) the shape of the theoretical spectra depends strongly on T(eff) but only very weakly on the hydrogen abundance; (2) the comparison of the observed and computed spectra permits to estimate T(eff) approximately 5500 K for V4334 Sgr in April, 1997, and its interstellar reddening (plus a possible circumstellar contribution) E(B-V) approximately 0.70.Comment: 7 pages, 8 figures, LaTeX, accepted by Astronomy and Astrophysic

    s-Process Nucleosynthesis in Carbon Stars

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    We present the first detailed and homogeneous analysis of the s-element content in Galactic carbon stars of N-type. Abundances of Sr,Y, Zr (low-mass s-elements, or ls) and of Ba, La, Nd, Sm and Ce (high-mass s-elements, hs) are derived using the spectral synthesis technique from high-resolution spectra. The N-stars analyzed are of nearly solar metallicity and show moderate s-element enhancements, similar to those found in S stars, but smaller than those found in the only previous similar study (Utsumi 1985), and also smaller than those found in supergiant post-AGB stars. This is in agreement with the present understanding of the envelope s-element enrichment in giant stars, which is increasing along the spectral sequence M-->MS-->S-->SC-->C during the AGB phase. We compare the observational data with recent ss-process nucleosynthesis models for different metallicities and stellar masses. Good agreement is obtained between low mass AGB star models (M < 3 M_o) and s-elements observations. In low mass AGB stars, the 13C(alpha, n)16O reaction is the main source of neutrons for the s-process; a moderate spread, however, must exist in the abundance of 13C that is burnt in different stars. By combining information deriving from the detection of Tc, the infrared colours and the theoretical relations between stellar mass, metallicity and the final C/O ratio, we conclude that most (or maybe all) of the N-stars studied in this work are intrinsic, thermally-pulsing AGB stars; their abundances are the consequence of the operation of third dredge-up and are not to be ascribed to mass transfer in binary systems.Comment: 31 pages, 10 figures, 6 tables. Accepted in Ap

    The evolutionary status of the semiregular variable QYSge

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    Repeated spectroscopic observations made with the 6m telescope of yielded new data on the radial-velocity variability of the anomalous yellow supergiant QYSge. The strongest and most peculiar feature in its spectrum is the complex profile of NaI D lines, which contains a narrow and a very wide emission components. The wide emission component can be seen to extend from -170 to +120 km/s, and at its central part it is cut by an absorption feature, which, in turn, is split into two subcomponents by a narrow (16km/s at r=2.5) emission peak. An analysis of all the Vr values leads us to adopt for the star a systemic velocity of Vr=-21.1 km/s, which corresponds to the position of the narrow emission component of NaI. The locations of emission-line features of NaI D lines are invariable, which point to their formation in regions that are external to the supergiant's photosphere. Differential line shifts of about 10km/s are revealed. The absorption lines in the spectrum of QYSge have a substantial width of FWHM~45 km/s. The method of model atmospheres is used to determine the following parameters: Teff=6250K, lg g=2.0, and microturbulence Vt=4.5km/s. The metallicity of the star is found to be somewhat higher than the solar one with an average overabundance of iron-peak elements of [Met/H]=+0.20. The star is found to be slightly overabundant in carbon and nitrogen, [C/Fe]=+0.25, [N/Fe]=+0.27. The alpha-process elements Mg, Si, and Ca are slightly overabundant [alpha/H]=+0.12. The strong sodium excess, [Na/Fe]=+0.75, is likely to be due to the dredge-up of the matter processed in the NeNa cycle. Heavy elements of the s-process are underabundant relative to the Sun. On the whole, the observed properties of QYSge do not give grounds for including this star into the group of RCrB or RVTau-type type objects.Comment: 29 pages, 8 figures, 4 tables; accepted by Astrophys. Bulleti

    Peculiarities and variations in the optical spectrum of the post-AGB star V448Lac=IRAS22223+4327

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    Repeated observations with high spectral resolution acquired in 1998-2008 are used to study the temporal behavior of the spectral line profiles and velocity field in the atmosphere and circumstellar envelope of the post-AGB star V448Lac. Asymmetry of the profiles of the strongest absorption lines with low-level excitation potentials less 1eV and time variations of these profiles have been detected, most prominently the profiles of the resonance lines of BaII, YII, LaII, SiII. The peculiarity of these profiles can be explained using a superposition of stellar absorption line and shell emission lines. Emission in the (0;1) 5635A Swan band of the C2 molecule has been detected in the spectrum of V448Lac for the first time. The core of the Halpha line displays radial velocity variations with an amplitude ~8 km/s. Radial velocity variations displayed by weakest metallic lines with lower amplitudes, 1-2 km/s, may be due to atmospheric pulsations. Differential line shifts, 0 -- 8 km/s, have been detected on various dates. The position of the molecular spectrum is stationary in time, indicating a constant expansion velocity of the circumstellar shell, Vexp=15.2 km/s, as derived from the C2 and NaI lines.Comment: 19 pages, 8 figures, 1 tabl

    Rational Design of Pathogen-Mimicking Amphiphilic Materials as Nanoadjuvants

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    An opportunity exists today for cross-cutting research utilizing advances in materials science, immunology, microbial pathogenesis, and computational analysis to effectively design the next generation of adjuvants and vaccines. This study integrates these advances into a bottom-up approach for the molecular design of nanoadjuvants capable of mimicking the immune response induced by a natural infection but without the toxic side effects. Biodegradable amphiphilic polyanhydrides possess the unique ability to mimic pathogens and pathogen associated molecular patterns with respect to persisting within and activating immune cells, respectively. The molecular properties responsible for the pathogen-mimicking abilities of these materials have been identified. The value of using polyanhydride nanovaccines was demonstrated by the induction of long-lived protection against a lethal challenge of Yersinia pestis following a single administration ten months earlier. This approach has the tantalizing potential to catalyze the development of next generation vaccines against diseases caused by emerging and re-emerging pathogens
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