Mixed oligopoly, public firm behavior, and free private entry

© 2012 Elsevier B.V. All rights reservedWe analyze a mixed oligopoly with free entry by private firms, assuming that a public firm maximizes an increasing function of output, subject to a break-even constraint. We establish an irrelevance result: whenever a mixed oligopoly is viable, then aggregate output, aggregate costs and welfare are the same with and without the public firm. However, replacing a viable mixed oligopoly with a public monopoly yields higher net welfare. Implications for privatization policy are suggested

XMM-Newton observation of the persistent Be/neutron-star system X Persei at a high-luminosity level

We report on the XMM-Newton observation of the HMXRB X Persei, the prototype of the persistent and low-luminosity Be/neutron star pulsars, which was performed on February 2003. The source was detected at a luminosity level of ~ 1.4x10^35 erg/s, which is the highest level of the latest three decades. The pulsation period has increased up to 839.3 s, thus confirming the overall spin-down of the NS detected in the previous observations. The folded light-curve has a complex structure, with features not observed at lower luminosities, and shows a significant energy dependence. The spectral analysis reveals the presence of a significant excess at low energies over the main power-law spectral component, which can be described by a black-body spectrum of high temperature (kT_BB ~ 1.5 keV) and small emitting region (R_BB ~ 340 m); its properties are consistent with a polar-cap origin. Phase-resolved spectroscopy shows that the emission spectrum varies along the pulse period, but it is not possible to prove whether the thermal component is pulsed or not.Comment: 8 pages, 8 figures, 4 tables. Accepted for publication by Astronomy & Astrophysic

Sculptors’ Papers from the Henry Moore Institute Archive

Why do public art commissions spark such controversy? The stories behind radical proposals for public sculptures in London – some realised, others thwarted – are drawn from the Henry Moore Institute’s rich collection of sculptors’ papers. Laurence Bradshaw’s (1899–1978) iconic Karl Marx memorial (1956) became an ideological site prompting both pilgrimage and attack. Jacob Epstein’s (1880–1959) explicit nudes for the British Medical Association became a battleground for Modernism and are the subject of a new work by Neal White (b. 1966). Other featured artists include Rose Finn-Kelcey, Alfred Frank Hardiman, Paul Neagu and Oscar Nemon whose drawings and documents reveal sculpture’s passage into public life

High resolution radio study of the Pulsar Wind Nebula within the Supernova Remnant G0.9+0.1

We have conducted a radio study at 3.6, 6 and 20 cm using ATCA and VLA and reprocessed XMM-Newton and Chandra data of the pulsar wind nebula (PWN) in the supernova remnant (SNR) G0.9+0.1. The new observations revealed that the morphology and symmetry suggested by Chandra observations (torus and jet-like features) are basically preserved in the radio range in spite of the rich structure observed in the radio emission of this PWN, including several arcs, bright knots, extensions and filaments. The reprocessed X-ray images show for the first time that the X-ray plasma fills almost the same volume as the radio PWN. Notably the X-ray maximum does not coincide with the radio maximum and the neutron star candidate CXOU J174722.8-280915 lies within a small depression in the radio emission. From the new radio data we have refined the flux density estimates, obtaining S(PWN) ~ 1.57 Jy, almost constant between 3.6 and 20 cm. For the whole SNR (compact core and shell), a flux density S(at 20 cm)= 11.5 Jy was estimated. Based on the new and the existing 90 cm flux density estimates, we derived alpha(PWN)=-0.18+/-0.04 and alpha(shell)=-0.68+/- 0.07. From the combination of the radio data with X-ray data, a spectral break is found near nu ~ 2.4 x 10^(12) Hz. The total radio PWN luminosity is L(radio)=1.2 x 10^(35) erg s^(-1) when a distance of 8.5 kpc is adopted. By assuming equipartition between particle and magnetic energies, we estimate a nebular magnetic field B = 56 muG. The associated particle energy turns out to be U(part)=5 x 10^(47) erg and the magnetic energy U(mag)=2 x 10^(47) erg. Based on an empirical relation between X-ray luminosity and pulsar energy loss rate, and the comparison with the calculated total energy, a lower limit of 1100 yr is derived for the age of this PWN.Comment: 10 pages,8 figures, accepted for publication in A&A, June 13 200

Electrocardiographic safety evaluation of dihydroartemisinin piperaquine in the treatment of uncomplicated falciparum malaria.

Dihydroartemisinin-piperaquine (DP) could become a leading fixed combination malaria treatment worldwide. Although there is accumulating evidence of efficacy and safety from clinical trials, data on cardiotoxicity are limited. In two randomized controlled trials in Thailand, 56 patients had ECGs performed before treatment, 4 hours after the first dose, and 4 hours after the last dose. The mean (95% CI) changes in QTc interval (Bazett's correction) were 2 (-6 to 9) ms and 14 (7 to 21) ms, respectively. These small changes on the third day of treatment are similar to those observed elsewhere in the convalescent phase following antimalarial treatment with drugs known to have no cardiac effects and are therefore likely to result from recovery from acute malaria and not the treatment given. At therapeutic doses, DP does not have clinically significant effects on the electrocardiogram

SPIDER - IV. Optical and NIR color gradients in Early-type galaxies: New Insights into Correlations with Galaxy Properties

We present an analysis of stellar population gradients in 4,546 Early-Type Galaxies with photometry in $grizYHJK$ along with optical spectroscopy. A new approach is described which utilizes color information to constrain age and metallicity gradients. Defining an effective color gradient, $\nabla_{\star}$, which incorporates all of the available color indices, we investigate how $\nabla_{\star}$ varies with galaxy mass proxies, i.e. velocity dispersion, stellar (M_star) and dynamical (M_dyn) masses, as well as age, metallicity, and alpha/Fe. ETGs with M_dyn larger than 8.5 x 10^10, M_odot have increasing age gradients and decreasing metallicity gradients wrt mass, metallicity, and enhancement. We find that velocity dispersion and alpha/Fe are the main drivers of these correlations. ETGs with 2.5 x 10^10 M_odot =< M_dyn =< 8.5 x 10^10 M_odot, show no correlation of age, metallicity, and color gradients wrt mass, although color gradients still correlate with stellar population parameters, and these correlations are independent of each other. In both mass regimes, the striking anti-correlation between color gradient and alpha-enhancement is significant at \sim 4sigma, and results from the fact that metallicity gradient decreases with alpha/Fe. This anti-correlation may reflect the fact that star formation and metallicity enrichment are regulated by the interplay between the energy input from supernovae, and the temperature and pressure of the hot X-ray gas in ETGs. For all mass ranges, positive age gradients are associated with old galaxies (>5-7 Gyr). For galaxies younger than \sim 5 Gyr, mostly at low-mass, the age gradient tends to be anti-correlated with the Age parameter, with more positive gradients at younger ages.Comment: Accepted for Publication in the Astronomical Journa

Spectral properties of the X-ray binary pulsar LMC X-4 during different intensity states

We present spectral variations of the binary X-ray pulsar LMC X-4 observed with the RXTE/PCA during different phases of its 30.5 day long third period. Only out of eclipse data were used for this study. The 3-25 keV spectrum, modeled with high energy cut-off power-law and iron line emission is found to show strong dependence on the intensity state. Correlations between the Fe line emission flux and different parameters of the continuum are presented here.Comment: 4 pages, 4 figure

Implementing social health insurance in Ireland: Report of a meeting and workshop held in Dublin, on December 6th 2010

We considered two basic questions, 'Is it possible to implement Social Health Insurance in Ireland?', and 'How can this be done?'. Can Social Health Insurance be implemented in Ireland? Our answer is a very definite yes. Furthermore, there would be many opportunities, while working towards this end, to improve the performance of our health care system. How can it be implemented? This process will need to be actively managed. There are many difficulties in the Irish health services, but also many opportunities. The greatest strengths are the talented, well-trained and very committed staff. Getting and keeping the support of these staff, for the necessary changes in service delivery, will be critical. Ireland has the capacity to make these changes, but without high quality management, a detailed focussed plan for change, and political support, little will happen. Each step in the change needs to be planned to maintain services, improve service delivery, improve service accountability, and improve service governance. Each sector of the service will need someone to lead the change, and mind that service during the change. Primary care remains under-developed. The HSE plan to develop primary care teams (PCT) has not succeeded. There are several established PCTs which work well. In other areas there are informal arrangements for collaboration, which work well. Overall, there are many useful lessons to learn from the experience so far. Future developments will need to place general practice at the centre of primary care. The mechanisms for doing this will vary from place to place, but need to be developed urgently. Acute hospitals face a crisis of governance. Maurice Hayes' (1) recent report on Tallaght hospital gives an idea of the scale of the changes needed. Tallaght is, we believe, not atypical, and is reputed to be by no means the worst governed hospital in the system. This, alone, should provide a pressing motive for change. Redesigning Irish hospitals to a new mission of supporting primary care, of supporting care in the community where possible can, and must, be done. Long-term care for older people is also a challenge. We advise moving to an integrated needs based system with smooth transitions between different degrees of support at home, and different degrees of support in specialized housing facilities including nursing homes. A similar model should apply to other forms of long-term care, for example for people with a substantial disability. Information systems and management processes both need a major overhaul. The health service remains strikingly under-managed, and fixing this will need a substantial culture change within the services. Wide use of standardized formal project management processes will be vital. There is a separate plan being developed to improve health service IT systems, and implementing this needs to be a high priority. We have not considered other key sectors, for example mental health, disability services, and social services. This does not mean that these are unimportant, merely that we had limited time, and a great deal to cover

Discovery of a Peculiar Dip from GX 301-2

We present temporal and spectral properties of a unique X-ray dip in GX 301-2 as seen with Rossi X-ray Timing Explorer in May 2010. The X-ray pulsation from the source gradually declined prior to the dip, disappears for one spin cycle during the dip and is abruptly restored in the spin cycle immediately after the dip. Moreover, the phase-integrated spectrum of the source becomes softer before and during the dip and it quickly hardens again following the dip. Our findings indicate the fact that the mechanism for pulsations gradually turned off briefly and underlying dim and softer emission likely from the accretion column became observable in the brief absence of high level emission due to wind accretion.Comment: Accepted for publication in A&A Letter