X-ray and UV observations of nova V598 Puppis between 147 and 255 days after outburst

Aims: The launch of Swift has allowed many more novae to be observed regularly over the X-ray band. Such X-ray observations of novae can reveal ejecta shocks and the nuclear burning white dwarf, allowing estimates to be made of the ejecta velocity. Methods: We analyse XMM-Newton and Swift X-ray and UV observations of the nova V598 Pup, which was initially discovered in the XMM-Newton slew survey. These data were obtained between 147 and 255 days after the nova outburst, and are compared with the earlier, brighter slew detection. Results: The X-ray spectrum consists of a super-soft source, with the soft emission becoming hotter and much fainter between days ~147 and ~172 after the outburst, and a more slowly declining optically thin component, formed by shocks with kT ~ 200-800 eV (corresponding to velocities of 400-800 km s^-1). The main super-soft phase had a duration of less than 130 days. The Reflection Grating Spectrometer data show evidence of emission lines consistent with optically thin emission of kT ~100 eV and place a limit on the density of the surrounding medium of log(n_e/cm^-3) < 10.4 at the 90 % level. The UV emission is variable over short timescales and fades by at least one magnitude (at lambda ~ 2246-2600 angstrom) between days 169 and 255.Comment: 6 pages, 5 figures, accepted for publication in A&

Keck-Nirspec Infrared OH Lines: Oxygen Abundances in Metal-Poor Stars Down to [Fe/H] = -2.9

Infrared OH lines at 1.5 - 1.7 um in the H band were obtained with the NIRSPEC high-resolution spectrograph at the 10m Keck Telescope for a sample of seven metal-poor stars. Detailed analyses have been carried out, based on optical high-resolution data obtained with the FEROS spectrograph at ESO. Stellar parameters were derived by adopting infrared flux method effective temperatures, trigonometric and/or evolutionary gravities and metallicities from FeII lines. We obtain that the sample stars with metallicities [Fe/H] < -2.2 show a mean oxygen abundance [O/Fe] ~ 0.54, for a solar oxygen abundance of epsilon(O) = 8.87, or [O/Fe] ~ 0.64 if epsilon(O) = 8.77 is assumed.Comment: To be published in ApJ 575 (August 10

Not Managing Expectations: A Grounded Theory of Intimate Partner Violence From the Perspective of Pakistani People

Intimate partner violence (IPV) is a major social and public health problem affecting people from different cultures and societies. Much research has been undertaken to understand the phenomenon, its determinants, and its consequences in numerous countries. However, there is a paucity of research on IPV in many areas of the world including Pakistan. The present study aimed to develop a theory of the meaning and process of IPV from the perspective of Pakistani men and women living in and outside Pakistan

Pre-nova X-ray observations of V2491 Cyg (Nova Cyg 2008b)

Classical novae are phenomena caused by explosive hydrogen burning on an accreting white dwarf. So far, only one classical nova has been identified in X-rays before the actual optical outburst occurred (V2487 Oph). The recently discovered nova, V2491 Cyg, is one of the fastest (He/N) novae observed so far. Using archival ROSAT, XMM-Newton and Swift data, we show that V2491 Cyg was a persistent X-ray source during its quiescent time before the optical outburst. We present the X-ray spectral characteristics and derive X-ray fluxes. The pre-outburst X-ray emission is variable, and at least in one observation it shows a very soft X-ray source.Comment: 4 pages, 2 figures. Astronomy and Astrophysics, in pres

Return to Hanging Rock: Lost Children in a Gothic Landscape

Using the philosophical position of phenomenology this article examines the ways in which ideas of wildness combine with Australian Gothic tropes such as the white colonial lost child and the bush as a haunted locale to compose key features of an Australian Ecogothic. Joan Lindsay’s enigmatic novel Picnic at Hanging Rock (1967) has prompted scholars such as Lesley Kathryn Hawkes to describe how in Australian literature for both adults and children ‘the environment is far more than a setting or backdrop against which the plot takes place’ (Hawkes, 2011,67). On St Valentine’s Day in 1900 three young Australian girls and their teacher disappear from a school picnic at the ancient site of Mount Macedon in Victoria. The analysis, which focuses on Lindsay’s posthumously published chapter eighteen (1987) examines how elements of the material, sensing world combine with the mythological or sacred to connect the human protagonists with the gothic landscape they inhabit. The resulting intersubjectivity problematizes colonial ideology and unsettles notions of national identity. Using the philosophical position of phenomenology this article examines the ways in which ideas of wildness combine with Australian Gothic tropes such as the white colonial lost child and the bush as a haunted locale to compose key features of an Australian Ecogothic. Joan Lindsay’s enigmatic novel Picnic at Hanging Rock (1967) has prompted scholars such as Lesley Kathryn Hawkes to describe how in Australian literature for both adults and children ‘the environment is far more than a setting or backdrop against which the plot takes place’ (Hawkes, 2011,67). On St Valentine’s Day in 1900 three young Australian girls and their teacher disappear from a school picnic at the ancient site of Mount Macedon in Victoria. The analysis, which focuses on Lindsay’s posthumously published chapter eighteen (1987) examines how elements of the material, sensing world combine with the mythological or sacred to connect the human protagonists with the gothic landscape they inhabit. The resulting intersubjectivity problematizes colonial ideology and unsettles notions of national identity

Analytical Bethe Ansatz for closed and open gl(n)-spin chains in any representation

We present an "algebraic treatment" of the analytical Bethe Ansatz. For this purpose, we introduce abstract monodromy and transfer matrices which provide an algebraic framework for the analytical Bethe Ansatz. It allows us to deal with a generic gl(n)-spin chain possessing on each site an arbitrary gl(n)-representation. For open spin chains, we use the classification of the reflection matrices to treat all the diagonal boundary cases. As a result, we obtain the Bethe equations in their full generality for closed and open spin chains. The classifications of finite dimensional irreducible representations for the Yangian (closed spin chains) and for the reflection algebras (open spin chains) are directly linked to the calculation of the transfer matrix eigenvalues. As examples, we recover the usual closed and open spin chains, we treat the alternating spin chains and the closed spin chain with impurity

Measurement of the rate of nu_e + d --> p + p + e^- interactions produced by 8B solar neutrinos at the Sudbury Neutrino Observatory

Solar neutrinos from the decay of $^8$B have been detected at the Sudbury Neutrino Observatory (SNO) via the charged current (CC) reaction on deuterium and by the elastic scattering (ES) of electrons. The CC reaction is sensitive exclusively to nu_e's, while the ES reaction also has a small sensitivity to nu_mu's and nu_tau's. The flux of nu_e's from ^8B decay measured by the CC reaction rate is \phi^CC(nu_e) = 1.75 +/- 0.07 (stat)+0.12/-0.11 (sys.) +/- 0.05(theor) x 10^6 /cm^2 s. Assuming no flavor transformation, the flux inferred from the ES reaction rate is \phi^ES(nu_x) = 2.39+/-0.34 (stat.)+0.16}/-0.14 (sys) x 10^6 /cm^2 s. Comparison of \phi^CC(nu_e) to the Super-Kamiokande Collaboration's precision value of \phi^ES(\nu_x) yields a 3.3 sigma difference, providing evidence that there is a non-electron flavor active neutrino component in the solar flux. The total flux of active ^8B neutrinos is thus determined to be 5.44 +/-0.99 x 10^6/cm^2 s, in close agreement with the predictions of solar models.Comment: 6 pages (LaTex), 3 figures, submitted to Phys. Rev. Letter

Somatic hypermutation and affinity maturation analysis using the 4-hydroxy-3-nitrophenyl-acetyl (NP) system

Somatic hypermutation of immunoglobulin variable region (IgV) genes and affinity maturation of the antibody response are the hallmarks of the germinal center (GC) reaction in T cell-dependent immune responses. Determining the consequences of the experimental manipulation of the GC response on somatic hypermutation and affinity maturation requires the availability of a system that allows measuring these parameters. Immunization of mice of the C57/Bl6 genetic background with the hapten 4-hydroxy-3-nitrophenyl-acetyl (NP) coupled to a carrier protein leads to the predominant usage of one particular IgV heavy chain gene segment, V186.2, among the responding B cells. Moreover, a specific somatic mutation in codon 33 of V186.2 that leads to a tryptophan to leucine amino acid exchange increases the affinity of the corresponding antibody by ~10-fold, thus representing a molecular marker for affinity maturation. In addition, due to the simplicity of the antigen and the virtual absence of NP-specific plasma cells prior to immunization, NP-based immunizations represent ideal tools to quantify the plasma cell response by measuring NP-specific antisera by ELISA and the generation of NP-specific plasma cells by ELISPOT analysis. We here describe approaches to (1) measure the anti-NP plasma cell response by ELISA and ELISPOT analysis, and to (2) amplify and sequence V186.2 rearrangements from GC B cells and plasma cells to determine the level of somatic hypermutation and the extent of affinity maturation in the anti-NP response

Chemical Abundances from Inversions of Stellar Spectra: Analysis of Solar-Type Stars with Homogeneous and Static Model Atmospheres

Spectra of late-type stars are usually analyzed with static model atmospheres in local thermodynamic equilibrium (LTE) and a homogeneous plane-parallel or spherically symmetric geometry. The energy balance requires particular attention, as two elements which are particularly difficult to model play an important role: line blanketing and convection. Inversion techniques are able to bypass the difficulties of a detailed description of the energy balance. Assuming that the atmosphere is in hydrostatic equilibrium and LTE, it is possible to constrain its structure from spectroscopic observations. Among the most serious approximations still implicit in the method is a static and homogeneous geometry. In this paper, we take advantage of a realistic three-dimensional radiative hydrodynamical simulation of the solar surface to check the systematic errors incurred by an inversion assuming a plane-parallel horizontally-homogeneous atmosphere. The thermal structure recovered resembles the spatial and time average of the three-dimensional atmosphere. Furthermore, the abundances retrieved are typically within 10% (0.04 dex) of the abundances used to construct the simulation. The application to a fairly complete dataset from the solar spectrum provides further confidence in previous analyses of the solar composition. There is only a narrow range of one-dimensional thermal structures able to fit the absorption lines in the spectrum of the Sun. With our carefully selected dataset, random errors are about a factor of two smaller than systematic errors. A small number of strong metal lines can provide very reliable results. We foresee no major difficulty in applying the technique to other similar stars, and obtaining similar accuracies, using spectra with a resolving power about 50,000 and a signal-to-noise ratio as low as 30.Comment: 65 pages, figures included; uses aastex; to appear in The Astrophysical Journa

Biggish Data: Friedrich Engels, Material Ecology, and Victorian Data

Through Friedrich Engels’ The Condition of the Working Class in England (1845), this article examines two prominent themes in environmental humanities – vital ecological materialism and ‘big data’. Engels’ vivid descriptions of factories, houses, and environment shared the central tenets of ‘material ecology’ – ‘thing power’ (Jane Bennett); ‘intra-actions’ of social and material agency (Karen Barad); ‘trans-corporeality’ (Stacy Alaimo) – and met Bennett’s call to align vital and historical materialism. The main body of the paper connects his analysis both to current debates about integrating ‘big data’ into social science and the humanities and to comparable nineteenth-century developments in statistics and data visualisation. Engels articulated the working-class condition by blending four distinct modes of investigation: big data; qualitative survey research; literary thick description; and theory (the nascent critique of capitalist political economy). Such a mix remains rich with possibilities for sociology and humanities not only in communicating but in generating knowledge about complex ecologies