4,161 research outputs found

    PATENT LICENSING BY MEANS OF AN AUCTION: INTERNAL VS. EXTERNAL PATENTEE

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    An independent research laboratory owns a patented process innovation that can be licensed by means of an auction to two Cournot duopolists producing differentiated goods. For large innovations and close enough substitute goods the patentee auctions o¤ only one license, preventing the full diffusion of the innovation. For this range of parameters, however, if the laboratory merged with one of the firms in the industry, full technology diffusion would be implemented as the merged entity would always license the innovation to the rival firm. This explains that, in this context, a vertical merger is both profitable and welfare improving.Patent licensing, two-part tariff contracts, vertical mergers

    Are the virial masses of clusters smaller than we think?

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    The constraints that the available X-ray spectral and imaging data place on the mass distribution and mass to light ratio of rich clusters are considered. It was found for the best determined cases that the mass to light ratio is less than 125 h sub 50 at radii exceeding 1 h sub 50 Mpc. The mass to light ratio is approximately constant at radii exceeding 1 h sub 50 Mpc but may rise to values of roughly 200 h sub 50 in the central regions. The fraction of the total mass that is in baryons, primarily the hot X-ray emitting gas, is roughly 30% thus setting the mass to light ratio of the dark material to roughly 70. The model that fits the X-ray data for Coma is in good agreement with the observed optical velocity dispersion vs. radius data

    Spitzer Observations of Gamma-Ray Burst Host Galaxies: A Unique Window into High Redshift Chemical Evolution and Star-formation

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    We present deep Spitzer 3.6 micron observations of three z~5 GRB host galaxies. Our observations reveal that z~5 GRB hosts are a factor of 3 less luminous than the median rest-frame V-band luminosity of spectroscopically confirmed z~5 galaxies in the GOODS fields and the UDF. The strong connection between GRBs and massive star formation implies that not all star-forming galaxies at these redshifts are currently being accounted for in deep surveys and GRBs provide a unique way to measure the contribution to the star-formation rate density from galaxies at the faint end of the galaxy luminosity function. By correlating the co-moving star-formation rate density with co-moving GRB rates at lower redshifts, we estimate a lower limit to the star-formation rate density of 0.12+/-0.09 and 0.09+/-0.05 M_sun/yr/Mpc^3 at z~4.5 and z~6, respectively. Finally, we provide evidence that the average metallicity of star-forming galaxies evolves as (stellar mass density)^(0.69+/-0.17) between z5z\sim5 and z0z\sim0, probably indicative of the loss of a significant fraction of metals to the intergalactic medium, particularly in low-mass galaxies.Comment: ApJ, in pres

    Use of hospital services by age and comorbidity after an index heart failure admission in England: an observational study

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    © Published by the BMJ Publishing Group Limited.Objectives To describe hospital inpatient, emergency department (ED) and outpatient department (OPD) activity for patients in the year following their first emergency admission for heart failure (HF). To assess the proportion receiving specialist assessment within 2â €...weeks of hospital discharge, as now recommended by guidelines. Design Observational study of national administrative data. Setting All acute NHS hospitals in England. Participants 82â €...241 patients with an index emergency admission between April 2009 and March 2011 with a primary diagnosis of HF. Main outcome measures Cardiology OPD appointment within 2â €...weeks and within a year of discharge from the index admission; emergency department (ED) and inpatient use within a year. Results 15.1% died during the admission. Of the 69â €...848 survivors, 19.7% were readmitted within 30â €...days and half within a year, the majority for non-HF diagnoses. 6.7% returned to the ED within a week of discharge, of whom the majority (77.6%) were admitted. The two most common OPD specialties during the year were cardiology (24.7% of the total appointments) and anticoagulant services (12.5%). Although half of all patients had a cardiology appointment within a year, the proportion within the recommended 2â €...weeks of discharge was just 6.8% overall and varied by age, from 2.4% in those aged 90+ to 19.6% in those aged 18-45 (p<0.0001); appointments in other specialties made up only some of the shortfall. More comorbidity at any age was associated with higher rates of cardiology OPD follow-up. Conclusions Patients with HF are high users of hospital services. Postdischarge cardiology OPD follow-up rates fell well below current National Institute for Health and Care Excellence guidelines, particularly for the elderly and those with less comorbidity

    The MicroJansky Radio Galaxy Population

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    We use highly spectroscopically complete observations of the radio sources from the VLA 1.4 GHz survey of the HDF-N region to study the faint radio galaxy population and its evolution. We spectrally classify the sources into four spectral types: absorbers, star formers, Seyfert galaxies, and broad-line AGNs, and we analyze their properties by type. We supplement the spectroscopic redshifts with photometric redshifts measured from the rest-frame UV to MIR spectral energy distributions. Using deep X-ray observations of the field, we do not confirm the existence of an X-ray-radio correlation for star-forming galaxies. We also do not observe any correlations between 1.4 GHz flux and R magnitude or redshift. We find that the radio powers of the host galaxies rise dramatically with increasing redshift, while the optical properties of the host galaxies show at most small changes. Assuming that the locally determined FIR-radio correlation holds at high redshifts, we estimate total FIR luminosities for the radio sources. We note that the FIR luminosity estimates for any radio-loud AGNs will be overestimates. Considering only the radio sources with quasar-like bolometric luminosities, we find a maximum ratio of candidate highly-obscured AGNs to X-ray-luminous (>10^42 ergs/s) sources of about 1.9. We use source-stacking analyses to measure the X-ray surface brightnesses of various X-ray and radio populations. We find the contributions to the 4-8 keV light from our candidate highly-obscured AGNs to be very small, and hence these sources are unable to account for the light that has been suggested may be missing at these energies.Comment: 20 pages, Accepted by The Astrophysical Journal (scheduled for 1 Jan 2007), color figures 2 and 3 can be found at http://www.astro.wisc.edu/~barger/radiopaper.htm

    Arrhenius parameters in the solvolysis of alkyl chlorides and bromides

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    The reactivities of alkyl halides, BX, in nucleophilic substitution reactions increase in the order RF C-C1 > C-Br > C-I. On the other hand some authors have concluded that a change in the entropy of activation, ΔS(^+) , plays the most important part in controlling reaction rate in this series. In many cases, however, the activation parameters of the different halides referred to different temperatures. Such comparisons may be misleading since recent work has clearly shown that E and ΔS(^+) can vary with temperature; any valid comparison of these parameters must, therefore, involve quantities which all refer to the same temperature.' A study of the reactions of several pairs of alkyl chlorides and bromides with aqueous acetone is now reported. Reaction rates, activation parameters and the temperature coefficients of these parameters have been determined and the results show that, for hydrolysis at the same temperature, the change in rate caused by replacing an alkyl chloride by the corresponding bromide arises almost entirely from a change in the activation energy; this applies to both S(_N)1 and S(_N)2 reactions. It has recently been suggested that the value of ΔC(^+)/ΔS(^+), where ΔC(^+) is the heat capacity of activation, should be independent of the nature of the substrate in SNl solvolysis and that this ratio will have a lower value for solvolysis by mechanism S(_N)2 under the same experimental conditions. This suggestion was based on results observed with alkyl chlorides. All the alkyl chlorides and bromides now studied behave in accordance with the requirements of this hypothesis. During this work the solvolysis of benzyl bromide was studied and the results indicated that this substance reacted by mechanism S(_N)2. This is of interest, for although the hydrolysis of benzyl chloride occurs near the point which marks the transition from reaction by mechanism S(_N)2 to reaction by mechanism S(_N)1, the replacement of the chlorine atom by a bromine atom does not appear to cause a major mechanistic change

    A new multi-modal dataset for human affect analysis

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    In this paper we present a new multi-modal dataset of spontaneous three way human interactions. Participants were recorded in an unconstrained environment at various locations during a sequence of debates in a video conference, Skype style arrangement. An additional depth modality was introduced, which permitted the capture of 3D information in addition to the video and audio signals. The dataset consists of 16 participants and is subdivided into 6 unique sections. The dataset was manually annotated on a continuously scale across 5 different affective dimensions including arousal, valence, agreement, content and interest. The annotation was performed by three human annotators with the ensemble average calculated for use in the dataset. The corpus enables the analysis of human affect during conversations in a real life scenario. We first briefly reviewed the existing affect dataset and the methodologies related to affect dataset construction, then we detailed how our unique dataset was constructed

    Detection of Massive Forming Galaxies at Redshifts Greater than One

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    The complex problem of when and how galaxies formed has not until recently been susceptible of direct attack. It has been known for some time that the excessive number of blue galaxies counted at faint magnitudes implies that a considerable fraction of the massive star formation in the universe occurred at z < 3, but, surprisingly, spectroscopic studies of galaxies down to a B magnitude of 24 found little sign of the expected high-z progenitors of current massive galaxies, but rather, in large part, small blue galaxies at modest redshifts z \sim 0.3. This unexpected population has diverted attention from the possibility that early massive star-forming galaxies might also be found in the faint blue excess. From KECK spectroscopic observations deep enough to encompass a large population of z > 1 field galaxies, we can now show directly that in fact these forming galaxies are present in substantial numbers at B \sim 24, and that the era from redshifts 1 to 2 was clearly a major period of galaxy formation. These z > 1 galaxies have very unusual morphologies as seen in deep HST WFPC2 images.Comment: 10 pages LaTeX + 5 PostScript figures in uuencoded gzipped tar file; aasms4.sty, flushrt.sty, overcite.sty (the two aastex4.0 and overcite.sty macros are available from xxx.lanl.gov) Also available (along with style files) via anonymous ftp to ftp://hubble.ifa.hawaii.edu/pub/preprints . E-print version of paper adds citation cross-references to other archived e-prints, where available. To appear in Nature October 19, 199
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