Taking a “Deep Dive”: What Only a Top Leader Can Do

Unlike most historical accounts of strategic change inside large firms, empirical research on strategic management rarely uses the day-to-day behaviors of top executives as the unit of analysis. By examining the resource allocation process closely, we introduce the concept of a deep dive, an intervention when top management seizes hold of the substantive content of a strategic initiative and its operational implementation at the project level, as a way to drive new behaviors that enable an organization to shift its performance trajectory into new dimensions unreachable with any of the previously described forms of intervention. We illustrate the power of this previously underexplored change mechanism with a case study, in which a well-established firm overcame barriers to change that were manifest in a wide range of organizational routines and behavioral norms that had been fostered by the pre-existing structural context of the firm.Strategic Change, Resource Allocation Process, Top-down Intervention

Gamma-ray emission from dark matter wakes of recoiled black holes

A new scenario for the emission of high-energy gamma-rays from dark matter annihilation around massive black holes is presented. A black hole can leave its parent halo, by means of gravitational radiation recoil, in a merger event or in the asymmetric collapse of its progenitor star. A recoiled black hole which moves on an almost-radial orbit outside the virial radius of its central halo, in the cold dark matter background, reaches its apapsis in a finite time. Near or at the apapsis passage, a high-density wake extending over a large radius of influence, forms around the black hole. It is shown that significant gamma-ray emission can result from the enhancement of neutralino annihilation in these wakes. At its apapsis passage, a black hole is shown to produce a flash of high-energy gamma-rays whose duration is determined by the mass of the black hole and the redshift at which it is ejected. The ensemble of such black holes in the Hubble volume is shown to produce a diffuse high-energy gamma-ray background whose magnitude is compared to the diffuse emission from dark matter haloes alone.Comment: version to appear in Astrophysical Journal letters (labels on Fig. 3 corrected

Detection of Evolved High-Redshift Galaxies in Deep NICMOS/VLT Images

A substantial population of high redshift early-type galaxies is detected in very deep UBVRIJHK images towards the HDF-South. Four elliptical profile galaxies are identified in the redshift range z=1-2, all with very red SEDs, implying ages of >2 Gyrs for standard passive evolution. We also find later type IR-luminous galaxies at similarly high redshift, (10 objects with z>1, H1 Gyr. The number and luminosity-densities of these galaxies are comparable with the local E/SO-Sbc populations for \Omega_m>0.2, and in the absence of a significant cosmological constant, we infer that the major fraction of luminous Hubble-sequence galaxies have evolved little since z~2. A highly complete photometric redshift distribution is constructed to H=25 (69 galaxies) showing a broad spread of redshift, peaking at z~1.5, in reasonable agreement with some analyses of the HDF. Five `dropout' galaxies are detected at z~3.8, which are compact in the IR, ~0.5 kpc/h at rest 3500\AA. No example of a blue IR luminous elliptical is found, restricting the star-formation epoch of ellipticals to z>10 for a standard IMF and modest extinction.Comment: 7 pages, 3 figures, accepted for publication in Astrophysical Journal Letters, discussion of clustering added, color image available at http://astro.berkeley.edu/~tjb/nic3.htm

Inappropriate Antidiuresis: Examples of an Hyponatremic Syndrome Resembling Exogenous Vasopressin Administration in Man

We have reviewed some of the features of hyponatremic syndromes, unassociated with sodium retention and edema, but associated with primary water retention. The syndromes were probably caused by excessive vasopressin activity, in the presence of normal circulatory, renal and adreno-cortical function. Underlying diseases, including bronchogenic carcinoma, head injury, and tuberculous meningitis, illustrated the diverse etiologic bases of this condition

HER2/HER3 regulates lactate secretion and expression of lactate receptor mRNA through the MAP3K4 associated protein GIT1

One of the major features of cancer is Otto Warburg's observation that many tumors have increased extracellular acidification compared to healthy tissues. Since Warburg's observation, the importance of extracellular acidification in cancer is now considered a hallmark of cancer. Human MAP3K4 functions upstream of the p38 and JNK mitogen activated protein kinases (MAPKs). Additionally, MAP3K4 is required for cell migration and extracellular acidification of breast cancer cells in response to HER2/HER3 signaling. Here, we demonstrate that GIT1 interacts with MAP3K4 by immunoprecipitation, while cellular lactate production and the capacity of MCF-7 cells for anchorage independent growth in soft agar were dependent on GIT1. Additionally, we show that activation of HER2/HER3 signaling leads to reduced expression of lactate receptor (GPR81) mRNA and that both, GIT1 and MAP3K4, are necessary for constitutive expression of GPR81 mRNA. Our study suggests that targeting downstream proteins in the HER2/HER3-induced extracellular lactate signaling pathway may be a way to inhibit the Warburg Effect to disrupt tumor growth.NIEHS Training grant [ES007091]; Arizona Science Foundation [CAA 0226-08, ES006694, ES012007, ES04940]Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

HST STIS spectroscopy of the triple nucleus of M31: two nested disks in Keplerian rotation around a Supermassive Black Hole

We present HST spectroscopy of the nucleus of M31 obtained with STIS. Spectra taken around the CaT lines at 8500 see only the red giants in the double bright- ness peaks P1 and P2. In contrast, spectra taken at 3600-5100 A are sensitive to the tiny blue nucleus embedded in P2, the lower surface brightness red nucleus. P2 has a K-type spectrum, but the embedded blue nucleus has an A-type spectrum with strong Balmer absorption lines. Given the small likelihood for stellar collisions, a 200 Myr old starburst appears to be the most plausible origin of the blue nucleus. In stellar population, size, and velocity dispersion, the blue nucleus is so different from P1 and P2 that we call it P3. The line-of-sight velocity distributions of the red stars in P1+P2 strengthen the support for Tremaine s eccentric disk model. The kinematics of P3 is consistent with a circular stellar disk in Keplerian rotation around a super-massive black hole with M_bh = 1.4 x 10^8 M_sun. The P3 and the P1+P2 disks rotate in the same sense and are almost coplanar. The observed velocity dispersion of P3 is due to blurred rotation and has a maximum value of sigma = 1183+-201 km/s. The observed peak rotation velocity of P3 is V = 618+-81 km/s at radius 0.05" = 0.19 pc corresponding to a circular rotation velocity at this radius of ~1700 km/s. Any dark star cluster alternative to a black hole must have a half-mass radius <= 0.03" = 0.11 pc. We show that this excludes clusters of brown dwarfs or dead stars on astrophysical grounds.Comment: Astrophysical Journal, Sep 20, 2005, 21 pages including 20 figure

Probing the evolution of early-type cluster galaxies through chemical enrichment

A simple chemical enrichment model for cluster early-type galaxies is described in which the mechanisms considered in the evolutionary model are infall of primordial gas, outflows and a possible variation in the star formation efficiency. We find that - within the framework of our models - only outflows can generate a suitable range of metallicities. The chemical enrichment tracks can be combined with the latest population synthesis models to simulate clusters over a wide redshift range, for a set of toy models. The color-magnitude relation of local clusters is used as a constraint, fixing the correlation between absolute luminosity and ejected fraction of gas from outflows. It is found that the correlations between color or mass-to-light ratios and absolute luminosity are degenerate with respect to most of the input parameters. However, a significant change between monolithic and hierarchical models is predicted for redshifts z\simgt 1. The comparison between predicted and observed mass-to-light ratios yield an approximate linear bias between total and stellar masses: $M_{\rm Tot}\propto M_{\rm St}^{1.15\pm 0.08}$ in early-type galaxies. If we assume that outflows constitute the driving mechanism for the colors observed in cluster early type galaxies, the metallicity of the intracluster medium (ICM) can be linked to outflows. The color-magnitude constraint requires faint $M_V\sim -16$ galaxies to eject 85% of their gas, which means that most of the metals in the ICM may have originated in these dwarf galaxies.Comment: Accepted for publication in ApJ. Uses emulateapj.sty. 12 pages with 10 embedded EPS figure

Feedback Processes in Early-Type Galaxies

We present a phenomenological model of feedback in early-type galaxies that tracks the evolution of the interstellar medium gas mass, metallicity, and temperature. Modeling the star formation rate as a Schmidt law with a temperature-dependent efficiency, we find that intermittent episodes of star formation are common in moderate-size ellipticals. Our model is applicable in the case in which the thermalization time from SN is sufficiently long that spatial variations are relatively unimportant, an appropriate assumption for the empirical parameters adopted here. The departure from a standard scenario of passive evolution implies significantly younger luminosity-weighted ages for the stellar populations of low-mass galaxies at moderate redshifts, even though the more physically meaningful mass-weighted ages are changed only slightly. Secondary bursts of star formation also lead to a natural explanation of the large scatter in the NUV-optical relation observed in clusters at moderate redshift and account for the population of E+A galaxies that display a spheroidal morphology. As the late-time formation of stars in our model is due to the gradual cooling of the interstellar medium, which is heated to temperatures ~1 keV by the initial burst of supernovae, our conclusions do not rely on any environmental effects or external mechanisms. Furthermore, a simple estimate of the X-ray emission from this supernova heated gas leads to an L_X vs L_B correlation that is in good agreement with observed values. Thus feedback processes may be essential to understanding the observed properties of early-type galaxies from the optical to the X-ray.Comment: Accepted for publication in ApJ. Uses emulateapj.sty. 12 pages with 8 embedded EPS figure

The SAURON project. II. Sample and early results

Early results are reported from the SAURON survey of the kinematics and stellar populations of a representative sample of nearby E, S0 and Sa galaxies. The survey is aimed at determining the intrinsic shape of the galaxies, their orbital structure, the mass-to-light ratio as a function of radius, the age and metallicity of the stellar populations, and the frequency of kinematically decoupled cores and nuclear black holes. The construction of the representative sample is described, and its properties are illustrated. A comparison with long-slit spectroscopic data establishes that the SAURON measurements are comparable to, or better than, the highest-quality determinations. Comparisons are presented for NGC 3384 and NGC 4365 where stellar velocities and velocity dispersions are determined to a precision of 6 km/s, and the h3 and h4 parameters of the line-of-sight velocity distribution to a precision of better than 0.02. Extraction of accurate gas emission-line intensities, velocities and line widths from the datacubes is illustrated for NGC 5813. Comparisons with published line-strengths for NGC 3384 and NGC 5813 reveal uncertainties of < 0.1 A on the measurements of the Hbeta, Mgb and Fe5270 indices. Integral-field mapping uniquely connects measurements of the kinematics and stellar populations to the galaxy morphology. The maps presented here illustrate the rich stellar kinematics, gaseous kinematics, and line-strength distributions of early-type galaxies. The results include the discovery of a thin, edge-on, disk in NGC 3623, confirm the axisymmetric shape of the central region of M32, illustrate the LINER nucleus and surrounding counter-rotating star-forming ring in NGC 7742, and suggest a uniform stellar population in the decoupled core galaxy NGC 5813.Comment: 20 pages, 17 figures. To be published in MNRAS. Version with full resolution images available at http://www.strw.leidenuniv.nl/~dynamics/Instruments/Sauron/pub_list.htm