Expression of beta human chorionic gonadotrophin by non-trophoblastic non-endocrine 'normal' and malignant epithelial cells.

Expression of hCG and its free subunits by non-trophoblastic tumours is well recognised. Previously we reported hCG secretion by normal and malignant bladder epithelial cells in vitro. Here we examined culture medium from 83 different cell lines derived mainly from common epithelial tumours. Thirty-two of the cell lines were found to secrete hCG-like material into their culture media. Partial immunochemical characterisation showed that of these only choriocarcinoma and fetal tissue cell lines produced intact hCG and alpha subunit. The remaining 28 hCG-expressing epithelial cell lines, which are of mucosal origin, only secreted free beta subunit. Expression of free beta hCG by non-trophoblastic nonendocrine cells would appear to be especially characteristic of mucosal epithelia from the genitourinary and oral/respiratory tracts. Furthermore, this phenomenon may be characteristic of epithelium with transitional and/or squamous cell-like properties

First observation of Bs0 → D*s2+Xμ-ν decays

Using data collected with the LHCb detector in proton–proton collisions at a centre-of-mass energy of 7 TeV, the semileptonic decays B0s→D+sXμ−ν and B0s→D0K+Xμ−ν are detected. Two structures are observed in the D0K+ mass spectrum at masses consistent with the known Ds1(2536)+ and D∗s22573)+ mesons. The measured branching fractions relative to the total B0s semileptonic rate are B(B0s→D∗+s2Xμ−ν)/B(B0s→Xμ−ν) = (3.3±1.0±0.4)%, and B(B0s→D+s1Xμ−ν)/B(B0s→Xμ−ν) = (5.4±1.2±0.5)%, where the first uncertainty is statistical and the second is systematic. This is the first observation of the D∗+s2 state in B0s decays; we also measure its mass and width

Measurement of the Bs0-Bs0 oscillation frequency δms in Bs0→Ds-(3)π decays

The Bs0-Bs0 oscillation frequency δms is measured with 36 pb-1 of data collected in pp collisions at s=7TeV by the LHCb experiment at the Large Hadron Collider. A total of 1381 Bs0→Ds-π+ and Bs0→Ds-π+π-π + signal decays are reconstructed, with average decay time resolutions of 44 fs and 36 fs, respectively. An oscillation signal with a statistical significance of 4.6σ is observed. The measured oscillation frequency is δm s=17.63±0.11(stat)±0.02(syst)ps -1

Effective interactions and shell model studies of heavy tin isotopes

We present results from large-scale shell-model calculations of even and odd tin isotopes from 134Sn to 142}Sn with a shell-model space defined by the 1f7/2,2p3/2,0h9/2,2p1/2,1f5/2,0i13/2 single-particle orbits. An effective two-body interaction based on modern nucleon-nucleon interactions is employed. The shell-model results are in turn analyzed for their pairing content using a generalized seniority approach. Our results indicate that a pairing-model picture captures a great deal of the structure and the correlations of the lowest lying states for even and odd isotopes.Comment: 7 pages, revtex latex style, submitted to PR

Absolute luminosity measurements with the LHCb detector at the LHC

Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. Using data taken in 2010, LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the LHC with a centre-of-mass energy of 7 TeV. In addition to the classic ''van der Meer scan'' method a novel technique has been developed which makes use of direct imaging of the individual beams using beam-gas and beam-beam interactions. This beam imaging method is made possible by the high resolution of the LHCb vertex detector and the close proximity of the detector to the beams, and allows beam parameters such as positions, angles and widths to be determined. The results of the two methods have comparable precision and are in good agreement. Combining the two methods, an overal precision of 3.5% in the absolute luminosity determination is reached. The techniques used to transport the absolute luminosity calibration to the full 2010 data-taking period are presented

Micromagnetic simulations of interacting dipoles on a fcc lattice: Application to nanoparticle assemblies

Micromagnetic simulations are used to examine the effects of cubic and axial anisotropy, magnetostatic interactions and temperature on M-H loops for a collection of magnetic dipoles on fcc and sc lattices. We employ a simple model of interacting dipoles that represent single-domain particles in an attempt to explain recent experimental data on ordered arrays of magnetoferritin nanoparticles that demonstrate the crucial role of interactions between particles in a fcc lattice. Significant agreement between the simulation and experimental results is achieved, and the impact of intra-particle degrees of freedom and surface effects on thermal fluctuations are investigated.Comment: 10 pages, 9 figure

Homotopy Theory of Strong and Weak Topological Insulators

We use homotopy theory to extend the notion of strong and weak topological insulators to the non-stable regime (low numbers of occupied/empty energy bands). We show that for strong topological insulators in d spatial dimensions to be "truly d-dimensional", i.e. not realizable by stacking lower-dimensional insulators, a more restrictive definition of "strong" is required. However, this does not exclude weak topological insulators from being "truly d-dimensional", which we demonstrate by an example. Additionally, we prove some useful technical results, including the homotopy theoretic derivation of the factorization of invariants over the torus into invariants over spheres in the stable regime, as well as the rigorous justification of replacing $T^d$ by $S^d$ and $T^{d_k}\times S^{d_x}$ by $S^{d_k+d_x}$ as is common in the current literature.Comment: 11 pages, 3 figure