Effective Lagrangian Approach to Weak Radiative Decays of Heavy Hadrons

Motivated by the observation of the decay $\bar{B}\to \bar{K}^*\gamma$ by CLEO, we have systematically analyzed the two-body weak radiative decays of bottom and charmed hadrons. There exist two types of weak radiative decays: One proceeds through the short-distance $b\to s\gamma$ transition and the other occurs through $W$-exchange accompanied by a photon emission. Effective Lagrangians are derived for the $W$-exchange bremsstrahlung processes at the quark level and then applied to various weak electromagnetic decays of heavy hadrons. Predictions for the branching ratios of $\bar{B}^0\to D^{*0} \gamma,~\Lambda_b^0\to\Sigma_c^0\gamma,~\Xi_b^0\to \Xi_c^0\gamma$ and \Xi_b^0\to\xip_c^0\gamma are given. In particular, we found ${\cal B}(\bar{B}^0 \to D^{*0}\gamma)\approx 0.9\times 10^{-6}$. Order of magnitude estimates for the weak radiative decays of charmed hadrons: $~D^0\to \bar{K}^{*0}\gamma,~\Lambda_c^+\to\Sigma^+\gamma$ and $\Xi_c^0\to\Xi^0\gamma$ are also presented. Within this approach, the decay asymmetry for antitriplet to antitriplet heavy baryon weak radiative transitions is uniquely predicted by heavy quark symmetry. The electromagnetic penguin contribution to $\Lambda_b^0\to\Lambda\gamma$ is estimated by two different methods and its branching ratio is found to be of order $1\times 10^{-5}$. We conclude that weak radiative decays of bottom hadrons are dominated by the short-distance $b\to s\gamma$ mechanism.Comment: 28 pages + 3 figures (not included), CLNS 94/1278, IP-ASTP-04-94. [Main changes in this revised version: (i) Sect 2 and subsection 4.1 are revised, (ii) A MIT bag method for calculating the decay rate of $Lambda_b \to\Lambda+gamma$ is presented, (iii) All predictions are updated using the newly available 1994 Particle Data Group, and (iv) Appendix and subsections 3.3 and 4.4 are deleted.

Chromophobe renal cell cancer - review of the literature and potential methods of treating metastatic disease

Chromophobe renal cell carcinoma (ChRCC) is a subtype of renal cell carcinoma (RCC). ChRCC is diagnosed mainly in 6th decade of life. An incidence of ChRCC is similar in both men and woman. Eighty six percent of ChRCCs cases are diagnosed in stage 1 or 2. Prognosis of ChRCC is better than in other types of RCC. Five- and 10-year disease free survival (DFS) for ChRCC was 83.9% and 77.9%, respectively. Expression of immunohistological markers: cytokeratins (CK), vimentin, epithelial membrane antigen (EMA), CD10 could be potentially helpful in diagnosis of different subtypes of RCC. From all conventional RCC, CD 117 was detected (overexpression) in membrane of cells ChRCC

From peculiar morphologies to Hubble-type spirals: the relation between galaxy dynamics and morphology in star-forming galaxies at z similar to 1.5

We present an analysis of the gas dynamics of star-forming galaxies at z ∼ 1.5 using data from the KMOS Galaxy Evolution Survey. We quantify the morphology of the galaxies using HST CANDELS imaging parametrically and non-parametrically. We combine the H α dynamics from KMOS with the high-resolution imaging to derive the relation between stellar mass (M∗) and stellar specific angular momentum (j∗). We show that high-redshift star-forming galaxies at z ∼ 1.5 follow a power-law trend in specific stellar angular momentum with stellar mass similar to that of local late-type galaxies of the form j∗ ∝ M0.53 ± 0.10 ∗ . The highest specific angular momentum galaxies are mostly disc-like, although generally both peculiar morphologies and disc-like systems are found across the sequence of specific angular momentum at a fixed stellar mass. We explore the scatter within the j∗ – M∗ plane and its correlation with both the integrated dynamical properties of a galaxy (e.g. velocity dispersion, Toomre Qg, H α star formation rate surface density SFR) and its parametrized rest-frame UV / optical morphology (e.g. Sersic ´ index, bulge to total ratio, clumpiness, asymmetry, and concentration). We establish that the position in the j∗ – M∗ plane is strongly correlated with the star-formation surface density and the clumpiness of the stellar light distribution. Galaxies with peculiar rest-frame UV / optical morphologies have comparable specific angular momentum to disc- dominated galaxies of the same stellar mass, but are clumpier and have higher star formation rate surface densities. We propose that the peculiar morphologies in high-redshift systems are driven by higher star formation rate surface densities and higher gas fractions leading to a more clumpy interstellar medium.This work was supported by the Science and Technology Facilities Council (ST/L00075X/1). SG acknowledges the support of the Science and Technology Facilities Council through grant ST/N50404X/1 for support. EI acknowledges partial support from FONDECYT through grant N◦ 1171710. We thank the FMOSCOSMOS team for their invaluable contributions to the KGES target selection. ALT acknowledges support from STFC (ST/L00075X/1 and ST/P000541/1), ERC Advanced Grant DUSTYGAL (321334), and a Forrest Research Foundation Fellowship. LC is the recipient of an Australian Research Council Future Fellowship (FT180100066) funded by the Australian Government. Parts of this research were conducted by the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013

Relativistic superfluid models for rotating neutron stars

This article starts by providing an introductory overview of the theoretical mechanics of rotating neutron stars as developped to account for the frequency variations, and particularly the discontinuous glitches, observed in pulsars. The theory suggests, and the observations seem to confirm, that an essential role is played by the interaction between the solid crust and inner layers whose superfluid nature allows them to rotate independently. However many significant details remain to be clarified, even in much studied cases such as the Crab and Vela. The second part of this article is more technical, concentrating on just one of the many physical aspects that needs further development, namely the provision of a satisfactorily relativistic (local but not microscopic) treatment of the effects of the neutron superfluidity that is involved.Comment: 42 pages LateX. Contribution to Physics of Neutron Star Interiors, ed. D. Blasche, N.K. Glendenning, A. Sedrakian (ECT workshop, Trento, June 2000

Phase II study of continuous daily sunitinib dosing in patients with previously treated advanced non-small cell lung cancer

Background:Sunitinib malate (SUTENT) has promising single-agent activity given on Schedule 4/2 (4 weeks on treatment followed by 2 weeks off treatment) in advanced non-small cell lung cancer (NSCLC).Methods:We examined the activity of sunitinib on a continuous daily dosing (CDD) schedule in an open-label, multicentre phase II study in patients with previously treated, advanced NSCLC. Patients ⩾18 years with stage IIIB/IV NSCLC after failure with platinum-based chemotherapy, received sunitinib 37.5 mg per day. The primary end point was objective response rate (ORR). Secondary end points included progression-free survival (PFS), overall survival (OS), 1-year survival rate, and safety.Results:Of 47 patients receiving sunitinib, one patient achieved a confirmed partial response (ORR 2.1% (95% confidence interval (CI) 0.1, 11.3)) and 11 (23.4%) had stable disease (SD) ⩾8 weeks. Five patients had SD>6 months. Median PFS was 11.9 weeks (95% CI 8.6, 14.1) and median OS was 37.1 weeks (95% CI 31.1, 69.7). The 1-year survival probability was 38.4% (95% CI 24.2, 52.5). Treatment was generally well tolerated.Conclusions:The safety profile and time-to-event analyses, albeit relatively low response rate of 2%, suggest single-agent sunitinib on a CDD schedule may be a potential therapeutic agent for patients with advanced, refractory NSCLC

Possible Explanation Why \tau_{B^{\pm}}\sim\tau_{B^0} But \tau_{D^{\pm}}\sim \tau_{D^0}

Data show that \tau_{B^{\pm}}\sim\tau_{B^0}, but \tau_{D^{\pm}}\sim 2\tau_{D^0}. The naive interpretation which attributes \tau_{D^{\pm}}\sim 2\tau_{D^0} to a destructive interference between two quark diagrams for D^{\pm} decays, definitely fails in the B-case. We investigate Close and Lipkin's suggestion that the phases for producing radially excited states \psi_{2s} in the decay products of B-mesons can possess an opposite sign to the integrals for \psi_{1s} decay products. Their contributions can partially compensate each other to result in \tau_{B^{\pm}}\sim\tau_{B^0}. Since D-mesons are much lighter than B-mesons, such possibilities do not exist in D-decays.Comment: 14 pages, latex, 4 ps figures. to appear in Phys. Rev.

Masitinib (AB1010), a Potent and Selective Tyrosine Kinase Inhibitor Targeting KIT

International audienceBackground: The stem cell factor receptor, KIT, is a target for the treatment of cancer, mastocytosis, and inflammatory diseases. Here, we characterise the in vitro and in vivo profiles of masitinib (AB1010), a novel phenylaminothiazole-type tyrosine kinase inhibitor that targets KIT. Methodology/Principal Findings: In vitro, masitinib had greater activity and selectivity against KIT than imatinib, inhibiting recombinant human wild-type KIT with an half inhibitory concentration (IC50) of 200 ± 40 nM and blocking stem cell factor-induced proliferation and KIT tyrosine phosphorylation with an IC50 of 150 ± 80 nM in Ba/F3 cells expressing human or mouse wild-type KIT. Masitinib also potently inhibited recombinant PDGFR and the intracellular kinase Lyn, and to a lesser extent, fibroblast growth factor receptor 3. In contrast, masitinib demonstrated weak inhibition of ABL and c-Fms and was inactive against a variety of other tyrosine and serine/threonine kinases. This highly selective nature of masitinib suggests that it will exhibit a better safety profile than other tyrosine kinase inhibitors; indeed, masitinib-induced cardiotoxicity or genotoxicity has not been observed in animal studies. Molecular modelling and kinetic analysis suggest a different mode of binding than imatinib, and masitinib more strongly inhibited degranulation, cytokine production, and bone marrow mast cell migration than imatinib. Furthermore, masitinib potently inhibited human and murine KIT with activating mutations in the juxtamembrane domain. In vivo, masitinib blocked tumour growth in mice with subcutaneous grafts of Ba/F3 cells expressing a juxtamembrane KIT mutant. Conclusions: Masitinib is a potent and selective tyrosine kinase inhibitor targeting KIT that is active, orally bioavailable in vivo, and has low toxicit

Gammaherpesvirus-Driven Plasma Cell Differentiation Regulates Virus Reactivation from Latently Infected B Lymphocytes

Gammaherpesviruses chronically infect their host and are tightly associated with the development of lymphoproliferative diseases and lymphomas, as well as several other types of cancer. Mechanisms involved in maintaining chronic gammaherpesvirus infections are poorly understood and, in particular, little is known about the mechanisms involved in controlling gammaherpesvirus reactivation from latently infected B cells in vivo. Recent evidence has linked plasma cell differentiation with reactivation of the human gammaherpesviruses EBV and KSHV through induction of the immediate-early viral transcriptional activators by the plasma cell-specific transcription factor XBP-1s. We now extend those findings to document a role for a gammaherpesvirus gene product in regulating plasma cell differentiation and thus virus reactivation. We have previously shown that the murine gammaherpesvirus 68 (MHV68) gene product M2 is dispensable for virus replication in permissive cells, but plays a critical role in virus reactivation from latently infected B cells. Here we show that in mice infected with wild type MHV68, virus infected plasma cells (ca. 8% of virus infected splenocytes at the peak of viral latency) account for the majority of reactivation observed upon explant of splenocytes. In contrast, there is an absence of virus infected plasma cells at the peak of latency in mice infected with a M2 null MHV68. Furthermore, we show that the M2 protein can drive plasma cell differentiation in a B lymphoma cell line in the absence of any other MHV68 gene products. Thus, the role of M2 in MHV68 reactivation can be attributed to its ability to manipulate plasma cell differentiation, providing a novel viral strategy to regulate gammaherpesvirus reactivation from latently infected B cells. We postulate that M2 represents a new class of herpesvirus gene products (reactivation conditioners) that do not directly participate in virus replication, but rather facilitate virus reactivation by manipulating the cellular milieu to provide a reactivation competent environment

Unique establishment of procephalic head segments is supported by the identification of cis-regulatory elements driving segment-specific segment polarity gene expression in Drosophila

Anterior head segmentation is governed by different regulatory mechanisms than those that control trunk segmentation in Drosophila. For segment polarity genes, both initial mode of activation as well as cross-regulatory interactions among them differ from the typical genetic circuitry in the trunk and are unique for each of the procephalic segments. In order to better understand the segment-specific gene network responsible for the procephalic expression of the earliest active segment polarity genes wingless and hedgehog, we started to identify and analyze cis-regulatory DNA elements of these genes. For hedgehog, we could identify a cis-regulatory element, ic-CRE, that mediates expression specifically in the posterior part of the intercalary segment and requires promoter-specific interaction for its function. The intercalary stripe is the last part of the metameric hedgehog expression pattern that appears during embryonic development, which probably reflects the late and distinct establishment of this segment. The identification of a cis-regulatory element that is specific for one head segment supports the mutant-based observation that the expression of segment polarity genes is governed by a unique gene network in each of the procephalic segments. This provides further indication that the anterior-most head segments represent primary segments, which are set up independently, in contrast to the secondary segments of the trunk, which resemble true repetitive units

LISA Pathfinder: Understanding DWS noise performance for the LISA mission

ESA's L3 Laser Interferometer Space Antenna (LISA) mission contains a mechanism to compensate for out-of-plane angles between the received and emitted beams of the three satellites. Depending on the configuration of this Point-Ahead Angle Mechanism (PAAM) it is expected to contribute readout noise through Differential Wavefront Sensing (DWS). This was investigated with LISA Pathfinder (LPF) through a dedicated investigation. One of the two free-falling test masses was rotated via the on-board electrostatic actuators while the resulting angular noise in the differential interferometer between the two test masses was measured. For angles between −250 μrad to 250 μrad and corresponding contrast in the range of 59.4 % to 97.9 % an increased spectral density was found. The differential displacement noise remains almost unchanged for these misalignments.The Albert-Einstein-Institut acknowledges the support of the German Space Agency, DLR. The work is supported by the Federal Ministry for Economic Affairs and Energy based on a resolution of the German Bundestag (FKZ 50OQ0501 and FKZ 50OQ1601)