3,487 research outputs found

    The molecular polar disc in NGC 2768

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    We present CO(1-0) and CO(2-1) maps of the molecular polar disc in the elliptical galaxy NGC 2768 obtained at the IRAM Plateau de Bure Interferometer. The maps have a resolution of 2.6" x 2.3" and 1.2" x 1.2" for the CO(1-0) and CO(2-1) lines, respectively. The CO maps complete the unique picture of the interstellar medium (ISM) of NGC 2768; the dust, molecular gas, ionised gas and neutral hydrogen (HI) trace the recent acquisition of cold and cool gas over two orders of magnitude in radii (and much more in density). In agreement with the other ISM components, the CO distribution extends nearly perpendicularly to the photometric major axis of the galaxy. Velocity maps of the CO show a rotating polar disc or ring in the inner kiloparsec. This cool gas could lead to kinematic substructure formation within NGC 2768. However, the stellar velocity field and H-beta absorption linestrength maps from the optical integral-field spectrograph SAURON give no indication of a young and dynamically cold stellar population coincident with the molecular polar disc. Very recent or weak star formation, undetectable in linestrengths, nevertheless remains a possibility and could be at the origin of some of the ionised gas observed. Millimetre continuum emission was also detected in NGC 2768, now one of only a few low-luminosity active galactic nuclei with observed millimetre continuum emission.Comment: Accepted for publication in MNRAS, 11 pages, 8 figure

    Country characteristics and the incidence of capital income taxation on wages: an empirical assessment

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    This paper examines the incidence of corporate income taxes on wages using data from the US Bureau of Labor Statistics for 13 OECD countries. Within a wage-bargaining framework, our econometric analysis shows that a substantial share of the corporate tax burden is shifted from capital to labour. However, the magnitude of this shift is influenced importantly by country characteristics affecting the process of wage determination, such as the degree of capital mobility, a country's relative influence over the world price of output and trade unions’ strength

    A multi-scale study of infrared and radio emission from Scd galaxy M33

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    We investigate the energy sources of the infrared (IR) emission and their relation to the radio continuum emission at various spatial scales within the Scd galaxy M33. We use the wavelet transform to analyze IR data at the Spitzer wavelengths of 24, 70, and 160μ\mum, as well as recent radio continuum data at 3.6cm and 20cm. An Hα\alpha map serves as a tracer of the star forming regions and as an indicator of the thermal radio emission. We find that the dominant scale of the 70μ\mum emission is larger than that of the 24μ\mum emission, while the 160μ\mum emission shows a smooth wavelet spectrum. The radio and Hα\alpha maps are well correlated with all 3 MIPS maps, although their correlations with the 160μ\mum map are weaker. After subtracting the bright HII regions, the 24 and 70μ\mum maps show weaker correlations with the 20cm map than with the 3.6cm map at most scales. We also find a strong correlation between the 3.6cm and Hα\alpha emission at all scales. Comparing the results with and without the bright HII regions, we conclude that the IR emission is influenced by young, massive stars increasingly with decreasing wavelength from 160 to 24μ\mum. The radio-IR correlations indicate that the warm dust-thermal radio correlation is stronger than the cold dust-nonthermal radio correlation at scales smaller than 4kpc. A perfect 3.6cm-Hα\alpha correlation implies that extinction has no significant effect on Hα\alpha emitting structures.Comment: 15 pages, 10 figures, accepted for publication in the Astronomy and Astrophysics Journa

    The New Spectacle : How effective is mobile Augmented Reality as tool for the manifestation of dissent?

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    Hordes of Networked AR Creatives deploy Viral Virtual Media to overlay, then overwhelm closed Social Systems lodged in Physical Hierarchies (Manifest.AR 2011). The above quote taken from the Manifest.AR’s (2011) collective manifesto demonstrates the power its founders attributed to augmented reality technology (AR); in particular, its ability to disrupt closed physical hierarchies through a form of technologically induced ‘détournement’. Détournement is a stratagem devised, or at least, coined, by Debord (1967) as a method to resist and undermine the pervading spectacle of capitalist society “by challenging the meaning of something taken for granted”

    H-alpha Imaging of Early-type (Sa-Sab) Spiral Galaxies II. Global Properties

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    New results, based on one of the most comprehensive H-alpha imaging surveys of nearby Sa-Sab spirals completed to date, reveals early-type spirals to be a diverse group of galaxies that span a wide range in massive star formation rates. While the majority of Sa-Sab galaxies in our sample are forming stars at a modest rate, a significant fraction (~29%) exhibit star formation rates greater than 1 M(solar/yr), rivaling the most prolifically star forming late-type spirals. A similar diversity is apparent in the star formation history of Sa-Sab spirals as measured by their H-alpha equivalent widths. Consistent with our preliminary results presented in the first paper in this series, we find giant HII regions (L(H-alpha)>10^{39}erg/s) in the disks of 37% of early-type spirals. We suspect that recent minor mergers or past interactions are responsible for the elevated levels of H-alpha emission and perhaps, for the presence of giant HII regions in these galaxies.Comment: 42 pages and 17 figures (6 in jpg format, available upon request from the authors as postscript); to appear in the June issue of A

    Structural and solution speciation studies on selected [Cu(NN)(OO)] complexes and an investigation of their biomimetic activity, ROS generation and their cytotoxicity in normoxic, hypoxic and anoxic environments in MCF-7 breast cancer-derived cells

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    Reactive oxygen species(ROS) generation with subsequent DNA damage is one of the principle mechanisms of action assigned to copper-based anticancer complexes. The efficacy of this type of chemotherapeutic may be reduced in the low oxygen environment of tumours. In this study the cytotoxicity of three complexes, [Cu(dips)(phen)] (1), [Cu(ph)(phen)]·2H2O (2) and [Cu(ph)(bpy)]·H2O (3) (disp: 3,5-diisopropylsalicylate, phen: 1,10- phenanthroline, ph: phthalate, bpy: 2,2′-bipyridyl) were assessed for anticancer activity in the breast-cancer derived MCF-7 line under normoxic, hypoxic and anoxic conditions. In an immortalised keratinocyte HaCaT cell line, the cytotoxicity of complexes 2 and 3 was significantly reduced under both normoxic and hypoxic conditions, whilst the cytotoxicity of complex 1 was increased under hypoxic conditions. The ability of the complexes to generate ROS in the MCF-7 cell line was evaluated as was their ability to act as superoxide dismutase(SOD) and catalase mimics using a yeast cell assay. ROS generation was significant for complexes 2 and 3, less so for complex 1 though all three complexes had SOD mimetic ability. Given the ternary nature of the complexes, solution speciation studies were undertaken but were only successful for complex 3, due to solubility issues with the other two complexes. The concentration distribution of various species, formed in aqueous solution, was evaluated as a function of pH and confirmed that complex 3 is the dominant species at physiological pH in the mM concentration range. However, as its concentration diminishes, it experiences a progressive dissociation, leading to the formation of binary complexes of bpy alongside unbound phthalate. © 2023 The Author

    Legal systems, national governance and renewable energy investment : evidence from around the world

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    This paper examines renewable energy (RE) investment and the role of a country’s legal system in shaping investment decisions. Analysing data from 236 renewable energy companies between 2000 and 2017 across the world, our study establishes that those in a common law system are more responsive to growth opportunities in RE investment, while facing greater financial constraints than their counterparts in civil law systems. Our study demonstrates that the global imbalance in RE development is caused by the influence of a country’s legal system, which determines the regulatory and business ethos that impacts on the trajectory of investment, and by the varying degrees of accountability implicit in a country’s governance environment. Our research raises the implication that the opportunity costs of forgone economic gains are in direct conflict with long-term environmental goals, retarding the transition from carbon-based to sustainable sources of energy, and provides insights into how development can be stimulated by fiscal incentives, favourable regulations, societal engagement, improved access to finance and the alignment of national strategies. Our findings contribute to the economic literature of legal origin theory and establish fundamental principles for refining global RE development strategy and confronting the challenge of climate change
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