Tumour markers in breast cancer.

The clinical usefulness of 8 potential tumour markers has been evaluated in 69 patients with Stage I and II breast cancer and 57 patients with Stage III and IV. Serum CEA concentrations were raised in 13% of patients with local and 65% of those with advanced breast cancer. In patients with clinical evidence of progression or regression of tumour, serum CEA levels changed appropriately in 83% of cases. Taking 4 of the markers (carcinoembryonic antigen (CEA), lactalbumin, alpha subunit and haptoglobin) serum concentrations of one or more were raised in 33% of patients with local disease and 81% of those with advanced breast cancer. However, marker concentrations were often only marginally raised, and are unlikely to provide sensitive guide to tumour burden. CEA, lactalbumin and alpha subunit were detectable in 68%, 43% and 40% respectively of extracts of primary breast cancers

VLT Spectropolarimetry of the fast expanding Type Ia SN2006X

Using VLT-FORS1 we performed optical spectropolarimetric observations of the Type Ia SN2006X on 7 pre-maximum epochs (day -10 to day -1) and one post-maximum epoch (+39 days). The SN shows strong continuum interstellar polarization reaching about 8% at 4000A, characterized by a wavelength dependency that is substantially different from that of the Milky-Way dust mixture. Several SN features, like SiII 6355A and the CaII IR triplet, present a marked evolution. The CaII near-IR triplet shows a pronounced polarization (~1.4%) already on day -10 in correspondence with a strong high-velocity feature (HVF). The SiII polarization peaks on day -6 at about 1.1% and decreases to 0.8% on day -1. By day +39 no polarization signal is detected for the SiII line, while the CaII IR triplet shows a marked re-polarization at the level of 1.2%. As in the case of another strongly polarized SN (2004dt), no polarization was detected across the OI 7774A absorption. The fast-expanding SN2006X lies on the upper edge of the relation between peak polarization and decline rate, and it confirms previous speculations about a correlation between degree of polarization, expansion velocity, and HVF strength. The polarization of CaII detected in our last epoch, the most advanced ever obtained for a Type Ia SN, coincides in velocity with the outer boundary of the Ca synthesized during the explosion (15,000-17,000 km/s) in delayed-detonation models. This suggests a large scale chemical inhomogeneity as produced by off-center detonations, a rather small amount of mixing, or a combination of both effects. In contrast, the absence of polarization at the inner edge of the Ca-rich layer (8000-10,000 km/s) implies a substantial amount of mixing in these deeper regions.Comment: 28 pages, 39 figures, accepted for publication in Astronomy and Astrophysic

Planum temporale asymmetry in people who stutter

Previous studies have reported that the planum temporale - a language-related structure that normally shows a leftward asymmetry - had reduced asymmetry in people who stutter (PWS) and reversed asymmetry in those with severe stuttering. These findings are consistent with the theory that altered language lateralization may be a cause or consequence of stuttering. Here, we re-examined these findings in a larger sample of PWS. We evaluated planum temporale asymmetry in structural MRI scans obtained from 67 PWS and 63 age-matched controls using: 1) manual measurements of the surface area; 2) voxel-based morphometry to automatically calculate grey matter density. We examined the influences of gender, age, and stuttering severity on planum temporale asymmetry. The size of the planum temporale and its asymmetry were not different in PWS compared with Controls using either the manual or the automated method. Both groups showed a significant leftwards asymmetry on average (about one-third of PWS and Controls showed rightward asymmetry). Importantly, and contrary to previous reports, the degree of asymmetry was not related to stuttering severity. In the manual measurements, women who stutter had a tendency towards rightwards asymmetry but men who stutter showed the same degree of leftwards asymmetry as male Controls. In the automated measurements, Controls showed a significant increase in leftwards asymmetry with age but this relationship was not observed in PWS. We conclude that reduced planum temporale asymmetry is not a prominent feature of the brain in PWS and that the asymmetry is unrelated to stuttering severity. [Abstract copyright: Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Fuzzy Supernova Templates I: Classification

Modern supernova (SN) surveys are now uncovering stellar explosions at rates that far surpass what the world's spectroscopic resources can handle. In order to make full use of these SN datasets, it is necessary to use analysis methods that depend only on the survey photometry. This paper presents two methods for utilizing a set of SN light curve templates to classify SN objects. In the first case we present an updated version of the Bayesian Adaptive Template Matching program (BATM). To address some shortcomings of that strictly Bayesian approach, we introduce a method for Supernova Ontology with Fuzzy Templates (SOFT), which utilizes Fuzzy Set Theory for the definition and combination of SN light curve models. For well-sampled light curves with a modest signal to noise ratio (S/N>10), the SOFT method can correctly separate thermonuclear (Type Ia) SNe from core collapse SNe with 98% accuracy. In addition, the SOFT method has the potential to classify supernovae into sub-types, providing photometric identification of very rare or peculiar explosions. The accuracy and precision of the SOFT method is verified using Monte Carlo simulations as well as real SN light curves from the Sloan Digital Sky Survey and the SuperNova Legacy Survey. In a subsequent paper the SOFT method is extended to address the problem of parameter estimation, providing estimates of redshift, distance, and host galaxy extinction without any spectroscopy.Comment: 26 pages, 12 figures. Accepted to Ap

Type Ia Supernovae as Stellar Endpoints and Cosmological Tools

Empirically, Type Ia supernovae are the most useful, precise, and mature tools for determining astronomical distances. Acting as calibrated candles they revealed the presence of dark energy and are being used to measure its properties. However, the nature of the SN Ia explosion, and the progenitors involved, have remained elusive, even after seven decades of research. But now new large surveys are bringing about a paradigm shift --- we can finally compare samples of hundreds of supernovae to isolate critical variables. As a result of this, and advances in modeling, breakthroughs in understanding all aspects of SNe Ia are finally starting to happen.Comment: Invited review for Nature Communications. Final published version. Shortened, update

The Transitional Stripped-Envelope SN 2008ax: Spectral Evolution and Evidence for Large Asphericity

Supernova (SN) 2008ax in NGC 4490 was discovered within hours after shock breakout, presenting the rare opportunity to study a core-collapse SN beginning with the initial envelope-cooling phase immediately following shock breakout. We present an extensive sequence of optical and near-infrared spectra, as well as three epochs of optical spectropolarimetry. Our initial spectra, taken two days after shock breakout, are dominated by hydrogen Balmer lines at high velocity. However, by maximum light, He I lines dominated the optical and near-infrared spectra, which closely resembled those of normal Type Ib supernovae (SNe Ib) such as SN 1999ex. This spectroscopic transition defines Type IIb supernovae, but the strong similarity of SN 2008ax to normal SNe Ib beginning near maximum light, including an absorption feature near 6270A due to H-alpha at high velocities, suggests that many objects classified as SNe Ib in the literature may have ejected similar amounts of hydrogen as SN 2008ax, roughly a few x 0.01 M_sun. Early-time spectropolarimetry (6 and 9 days after shock breakout) revealed strong line polarization modulations of 3.4% across H-alpha, indicating the presence of large asphericities in the outer ejecta. The continuum shares a common polarization angle with the hydrogen, helium, and oxygen lines, while the calcium and iron absorptions are oriented at different angles. This is clear evidence of deviations from axisymmetry even in the outer ejecta. Intrinsic continuum polarization of 0.64% only nine days after shock breakout shows that the outer layers of the ejecta were quite aspherical. A single epoch of late-time spectropolarimetry, as well as the shapes of the nebular line profiles, demonstrate that asphericities extended from the outermost layers all the way down to the center of this SN. [Abridged]Comment: 24 pages, 21 figures, 4 tables, appendix, minor revisions to match version accepted by Ap

WD + MS systems as the progenitor of SNe Ia

We show the initial and final parameter space for SNe Ia in a ($\log P^{\rm i}, M_{\rm 2}^{\rm i}$) plane and find that the positions of some famous recurrent novae, as well as a supersoft X-ray source (SSS), RX J0513.9-6951, are well explained by our model. The model can also explain the space velocity and mass of Tycho G, which is now suggested to be the companion star of Tycho's supernova. Our study indicates that the SSS, V Sge, might be the potential progenitor of supernovae like SN 2002ic if the delayed dynamical-instability model due to Han & Podsiadlowski (2006) is appropriate. Following the work of Meng, Chen & Han (2009), we found that the SD model (WD + MS) with an optically thick wind can explain the birth rate of supernovae like SN 2006X and reproduce the distribution of the color excess of SNe Ia. The model also predicts that at least 75% of all SNe Ia may show a polarization signal in their spectra.Comment: 6 pages, 2 figures, accepted for publication in Astrophysics & Space Science (Proceeding of the 4th Meeting on Hot Subdwarf Stars and Related Objects, edited by Zhanwen Han, Simon Jeffery & Philipp Podsiadlowski

SN 2014ab: An Aspherical Type IIn Supernova with Low Polarization

We present photometry, spectra, and spectropolarimetry of supernova (SN) 2014ab, obtained through $\sim 200$ days after peak brightness. SN 2014ab was a luminous Type IIn SN ($M_V < -19.14$ mag) discovered after peak brightness near the nucleus of its host galaxy, VV 306c. Prediscovery upper limits constrain the time of explosion to within 200 days prior to discovery. While SN 2014ab declined by $\sim 1$ mag over the course of our observations, the observed spectrum remained remarkably unchanged. Spectra exhibit an asymmetric emission-line profile with a consistently stronger blueshifted component, suggesting the presence of dust or a lack of symmetry between the far side and near side of the SN. The Pa$\beta$ emission line shows a profile very similar to that of H$\alpha$, implying that this stronger blueshifted component is caused either through obscuration by large dust grains, occultation by optically thick material, or a lack of symmetry between the far side and near side of the interaction region. Despite these asymmetric line profiles, our spectropolarimetric data show that SN 2014ab has little detected polarization after accounting for the interstellar polarization. This suggests that we are seeing emission from a photosphere that has only small deviation from circular symmetry face-on. We are likely seeing a SN IIn with nearly circular symmetry in the plane normal to our line of sight, but with either large-grain dust or significant asymmetry in the density of circumstellar material or SN ejecta along our line of sight. We suggest that SN 2014ab and SN 2010jl (as well as other SNe IIn) may be similar events viewed from different directions.Comment: 20 pages, 19 figure