On Seas of Glory: Heroic Men, GreatShips, and Epic Battles of the American Navy

John Lehman, former secretary of the Navy and author of Command of the Seas (1988), has with this book produced a masterful outline of “the grandeur of the American naval tradition.” The truest examples of this “grandeur” are “best found in its people, fighting sailors, technical innovators and inspiring leaders.” From John Paul Jones and the Revolutionary War to the six-hundred-ship fleet of the Cold War, John Lehman brings us a wonderful episodic view of the U.S. Navy’s people and ships, and their collective contribution to the strength and character of the nation they have served

The unbiased frequency of planetary signatures around single and binary white dwarfs using Spitzer{\it Spitzer} and Hubble{\it Hubble}

This paper presents combined ${\it Spitzer}$ IRAC and ${\it Hubble}$ COS results for a double-blind survey of 195 single and 22 wide binary white dwarfs for infrared excesses and atmospheric metals. The selection criteria include cooling ages in the range 9 to 300 Myr, and hydrogen-rich atmospheres so that the presence of atmospheric metals can be confidently linked to ongoing accretion from a circumstellar disc. The entire sample has infrared photometry, whereas 168 targets have corresponding ultraviolet spectra. Three stars with infrared excesses due to debris discs are recovered, yielding a nominal frequency of $1.5_{-0.5}^{+1.5}$ per cent, while in stark contrast, the fraction of stars with atmospheric metals is $45\pm4$ per cent. Thus, only one out of 30 polluted white dwarfs exhibits an infrared excess at 3-4 $\mu$m in IRAC photometry, which reinforces the fact that atmospheric metal pollution is the most sensitive tracer of white dwarf planetary systems. The corresponding fraction of infrared excesses around white dwarfs with wide binary companions is consistent with zero, using both the infrared survey data and an independent assessment of potential binarity for well-established dusty and polluted stars. In contrast, the frequency of atmospheric pollution among the targets in wide binaries is indistinct from apparently single stars, and moreover the multiplicity of polluted white dwarfs in a complete and volume-limited sample is the same as for field stars. Therefore, it appears that the delivery of planetesimal material onto white dwarfs is ultimately not driven by stellar companions, but by the dynamics of planetary bodies.Comment: 15 pages, 6 figures, 3 tables; accepted for publication in MNRA

The First World War Centenary in the UK: ‘A Truly National Commemoration’?

Prime Minister David Cameron has called for ‘a truly national commemoration of the First World War’. This article shows this to be problematic, politicised and contested. This is in part due to the elision of English and British histories. Scottish, Welsh and Irish responses are noted, and the role and commemorations of ‘our friends in the Commonwealth’. There are tensions around interpretations of empire and race. There has been a failure to appreciate that the debates about the legacies of the First World War are deeply entangled with those of colonialism

A new species of Rhodomyrtus (Myrtaceae) with brochidodromous venation from north-eastern Queensland, Australia.

Rhodomyrtus verecunda A.J.Ford & Peter G. Wilson from north-east Queensland, Australia, is formally described and illustrated. Notes on habitat, distribution and conservation status are provided, as are details of how it can be distinguished from R. macrocarpa, the only other species of the genus in the region that lacks acrodromous venation. A revised key to the species of Rhodomyrtus in Australia is also presented

A Chandra Observation of M51: Active Nucleus and Nuclear Outflows

We present a Chandra ACIS-S observation of the nuclear region of the nearby spiral galaxy M51 (NGC 5194), which has a low-luminosity Seyfert 2 nucleus. The X-ray image shows the nucleus, southern extranuclear cloud, and northern loop, the morphology of the extended emission being very similar to those seen in radio continuum and optical emission line images. The X-ray spectrum of the nucleus is well represented by a model consisting of soft thermal plasma with kT ~0.5 keV, a very hard continuum, and an Fe Kalpha emission line at 6.45 keV with an equivalent width of >2 keV. The very strong Fe line and the flat continuum indicate that the nucleus is obscured by a column density in excess of 10^24 cm^-2 and the spectrum is dominated by reflected emission from cold matter near the nucleus. The X-ray spectra of the extranuclear clouds are well fitted by a thermal plasma model with kT ~0.5 keV. This spectral shape and morphology strongly suggest that the clouds are shock heated by the bi-polar outflow from the nucleus. The shock velocities of the extranuclear cloud and northern loop inferred from the temperatures of the X-ray gas are 690 km/s and 660 km/s, respectively. By assuming a steady-state situation in which the emission of the extranuclear clouds is powered by the jets, the mechanical energy in the jets is found to be comparable to the bolometric luminosity of the nucleus.Comment: 7 pages, 5 figures, Accepted for publication in the Astrophyscal Jouna

An evolutionary perspective on the kinome of malaria parasites

Malaria parasites belong to an ancient lineage that diverged very early from the main branch of eukaryotes. The approximately 90-member plasmodial kinome includes a majority of eukaryotic protein kinases that clearly cluster within the AGC, CMGC, TKL, CaMK and CK1 groups found in yeast, plants and mammals, testifying to the ancient ancestry of these families. However, several hundred millions years of independent evolution, and the specific pressures brought about by first a photosynthetic and then a parasitic lifestyle, led to the emergence of unique features in the plasmodial kinome. These include taxon-restricted kinase families, and unique peculiarities of individual enzymes even when they have homologues in other eukaryotes. Here, we merge essential aspects of all three malaria-related communications that were presented at the Evolution of Protein Phosphorylation meeting, and propose an integrated discussion of the specific features of the parasite's kinome and phosphoproteome

The Caledonian face test: A new test of face discrimination

yesThis study aimed to develop a clinical test of face perception which is applicable to a wide range of patients and can capture normal variability. The Caledonian face test utilises synthetic faces which combine simplicity with sufficient realism to permit individual identification. Face discrimination thresholds (i.e. minimum difference between faces required for accurate discrimination) were determined in an "odd-one-out" task. The difference between faces was controlled by an adaptive QUEST procedure. A broad range of face discrimination sensitivity was determined from a group (N=52) of young adults (mean 5.75%; SD 1.18; range 3.33-8.84%). The test is fast (3-4min), repeatable (test-re-test r2=0.795) and demonstrates a significant inversion effect. The potential to identify impairments of face discrimination was evaluated by testing LM who reported a lifelong difficulty with face perception. While LM's impairment for two established face tests was close to the criterion for significance (Z-scores of -2.20 and -2.27) for the Caledonian face test, her Z-score was -7.26, implying a more than threefold higher sensitivity. The new face test provides a quantifiable and repeatable assessment of face discrimination ability. The enhanced sensitivity suggests that the Caledonian face test may be capable of detecting more subtle impairments of face perception than available tests.Non