The Changing Effect of HMO Market Structure: An Analysis of Penetration, Concentration, and Ownership Between 1994-2005

We analyze the role of three aspects of HMO market structure -- HMO penetration, HMO plan concentration, and HMO for-profit share on explaining hospital cost and revenue growth during the HMO expansion period (1994-1999) and backlash period (2000-2005). We find that HMO penetration effects differ over time: a 10 percentage point increase in HMO enrollment leads to 2.5 percent reduction in cost and revenues in the expansion period but only 0.4-1 percent reduction in the backlash period. Furthermore, this HMO backlash effect can be attributed to HMO dis-enrollment as well as the changing nature of HMO product. We find that revenue increases at a slower rate (by about 5 percent) in markets with relatively concentrated HMO markets power and more competitive hospital markets. Finally, increased for-profit HMO presence is associated with smaller cost and revenue growth, and the effect differs between low and high penetration markets.

Arp 302: Non-starburst Luminous Infrared Galaxies

Arp 302, a luminous infrared source (L_{IR} = 4.2x10^{11} Lsun), consisting of two spiral galaxies (VV340A and VV340B) with nuclear separation of 40'', has the highest CO luminosity known. Observations with the BIMA array at 5'' X 7'' resolution reveal that the CO emission is extended over 23.0 kpc in the edge-on spiral galaxy, VV340A, corresponding to 6.7x10^{10} Msun of H_2. In the companion face-on galaxy, VV340B, the CO emission is extended over ~10.0 kpc, with 1.1x10^{10} Msun of H_2. The large CO extent is in strong contrast to starburst systems, such as Arp 220, in which the CO extent is typically $\le$ 1 kpc. Furthermore, $L_{IR}/M$(H_2) is found to be $\le$ 6.0 Lsun/Msun throughout both galaxies. Thus the high IR luminosity of Arp 302 is apparently not due to starbursts in the nuclear regions, but is due to its unusually large amount of molecular gas forming stars at a rate similar to giant molecular clouds in the Milky Way disk. Arp 302 consists of a pair of very gas-rich spiral galaxies that may be interacting and in a phase before a likely onset of starbursts.Comment: AAS Latex plus two postscript figures. ApJ Letters (accepted

HST observations of the blue compact dwarf SBS 0335-052: a probable young galaxy

We present HST WFPC2 V and I images and GHRS UV spectrophotometry of the spectral regions around Ly$_alpha$ and OI 1302 of the extremely metal-deficient (Z~Zsun/41) blue compact dwarf (BCD) galaxy SBS 0335-052. All the star formation in the BCD occurs in six super-star clusters (SSC) with ages =< 3-4 Myr. Dust is clearly present and mixed spatially with the SSCs. There is a supershell of radius ~380 pc, delineating a large supernova cavity. The instantaneous star formation rate is ~0.4 Msun yr^-1. Strong narrow Ly$\alpha$ emission is not observed. Rather there is low intensity broad (FWZI = 20 A) Ly$\alpha$ emission superposed on even broader Ly$\alpha$ absorption by the HI envelope. This broad low-intensity emission is probably caused by resonant scattering of Ly$\alpha$ photons. The BCD appears to be a young galaxy, undergoing its very first burst of star formation. This conclusion is based on the following evidence: 1) the underlying extended low-surface-brightness component is very irregular and filamentary, suggesting that a significant part of the emission comes from ionized gas; 2) it has very blue colors (-0.34 =< (V-I)$_0$ =< 0.16), consistent with gaseous emission colors; 3) the OI 1302 line is not detected in absorption in the GHRS spectrum, setting an upper limit for N(O)/N(H) in the HI envelope of the BCD of more than 3000 times smaller than the value in Orion.Comment: 20 pages and 6 Postscript figures. Submitted to Astrophysical Journa

Single spin asymmetry measurements for π0\pi^0 inclusive productions in p+p↑→π0+Xp+p_{\uparrow} \to \pi^0 + X and \pi^-+\p_{\uparrow}\to \pi^0+X reactions at 70 and 40 GeV respectively

The inclusive $\pi^0$ asymmetries were measured in reactions $p+p\uparrow \to \pi^0+X$ and $\pi^-+p\uparrow \to \pi^0+X$ at 70 and 40 GeV/c respectively. The measurements were made at the central region (for the first reaction) and asymmetry is compatible with zero in the entire measured $p_T$ region. For the second reaction the asymmetry is zero for small $x_F$ region ($-0.4<x_F<-0.1, 0.5<p_T(GeV/c) <1.5$) and increases with growth of $\mid x_F\mid$. Averaged over the interval $-0.8<x_F<-0.4, 1<p_T(GeV/c)<2$ the asymmetry was $-(13.8\pm 3.8)$.Comment: 4 pages, 2 figures; Presented at SPIN-2004 at Trieste, October 10-16,200

BCL6 enables Ph+ acute lymphoblastic leukaemia cells to survive BCR-ABL1 kinase inhibition.

Tyrosine kinase inhibitors (TKIs) are widely used to treat patients with leukaemia driven by BCR-ABL1 (ref. 1) and other oncogenic tyrosine kinases. Recent efforts have focused on developing more potent TKIs that also inhibit mutant tyrosine kinases. However, even effective TKIs typically fail to eradicate leukaemia-initiating cells (LICs), which often cause recurrence of leukaemia after initially successful treatment. Here we report the discovery of a novel mechanism of drug resistance, which is based on protective feedback signalling of leukaemia cells in response to treatment with TKI. We identify BCL6 as a central component of this drug-resistance pathway and demonstrate that targeted inhibition of BCL6 leads to eradication of drug-resistant and leukaemia-initiating subclones

Mapping IR Enhancements in Closely Interacting Spiral-Spiral Pairs. I. ISO~CAM and ISO~SWS Observations

Mid-infrared (MIR) imaging and spectroscopic observations are presented for a well defined sample of eight closely interacting (CLO) pairs of spiral galaxies that have overlapping disks and show enhanced far-infrared (FIR) emission. The goal is to study the star formation distribution in CLO pairs, with special emphasis on the role of 'overlap starbursts'. Observations were made with the Infrared Space Observatory (ISO) using the CAM and SWS instruments. The ISO~CAM maps, tracing the MIR emission of warm dust heated by young massive stars, are compared to new ground based H$\alpha$ and R-band images. We identify three possible subgroups in the sample, classified according to the star formation morphology: (1) advanced mergers (Arp~157, Arp~244 and Arp~299), (2) severely disturbed systems (Arp~81 and Arp~278), and (3) less disturbed systems (Arp~276, KPG 347 and KPG 426). Localized starbursts are detected in the overlap regions in all five pairs of subgroups (1) and (2), suggesting that they are a common property in colliding systems. Except for Arp~244, the 'overlap starburst' is usually fainter than the major nuclear starburst in CLO pairs. Star formation in 'less disturbed systems' is often distributed throughout the disks of both galaxies with no 'overlap starburst' detected in any of them. These systems also show less enhanced FIR emission, suggesting that they are in an earlier interaction stage than pairs of the other two subgroups where the direct disk collisions have probably not yet occurred.Comment: 27 pages text, 4 JPEG figures, 3 PS figures. To be accepted by ApJ. High quality figures (included in a PS file of the paper) can be found in http://spider.ipac.caltech.edu/staff/cxu/papers/ss_iso.ps.g