801 research outputs found
The Stripe 82 1-2 GHz Very Large Array Snapshot Survey: Multiwavelength Counterparts
We have combined spectrosopic and photometric data from the Sloan Digital Sky
Survey (SDSS) with GHz radio observations, conducted as part of the
Stripe 82 GHz Snapshot Survey using the Karl G. Jansky Very Large Array
(VLA), which covers sq degrees, to a flux limit of 88 Jy rms.
Cross-matching the radio source components with optical data via
visual inspection results in a final sample of cross-matched objects,
of which have spectroscopic redshifts and objects have
photometric redshifts. Three previously undiscovered Giant Radio Galaxies
(GRGs) were found during the cross-matching process, which would have been
missed using automated techniques. For the objects with spectroscopy we
separate radio-loud Active Galactic Nuclei (AGN) and star-forming galaxies
(SFGs) using three diagnostics and then further divide our radio-loud AGN into
the HERG and LERG populations. A control matched sample of HERGs and LERGs,
matched on stellar mass, redshift and radio luminosity, reveals that the host
galaxies of LERGs are redder and more concentrated than HERGs. By combining
with near-infrared data, we demonstrate that LERGs also follow a tight
relationship. These results imply the LERG population are hosted by population
of massive, passively evolving early-type galaxies. We go on to show that
HERGs, LERGs, QSOs and star-forming galaxies in our sample all reside in
different regions of a WISE colour-colour diagram. This cross-matched sample
bridges the gap between previous `wide but shallow' and `deep but narrow'
samples and will be useful for a number of future investigations.Comment: 17 pages, 19 figures. Resubmitted to MNRAS after the initial comment
Droppings From Captive Coturnix coturnix (Galliformes: Phasianidae) as a Fly Breeding Resource
The aim of this study was to describe the fauna of flies associated with captive Coturnix coturnix (L.) (Galliformes: Phasianidae) droppings. Samples of 150 g of quail droppings were exposed in the quail house for 48 h in plastic containers to promote eventual access of flies, and then placed in emergence traps. The number of adults and species emerging was recorded daily. This procedure was carried out in spring 2008 and spring and autumn 2009. In total, 2,138 adults belonging to Muscidae, Calliphoridae, Piophilidae, Phoridae, Fanniidae, and Milichiidae families were collected. The most numerous family was Muscidae (representing >82% of the total specimens), with Musca domestica L. being the most abundant species followed by Ophyra aenescens (Wiedemann) (both Diptera: Muscidae). Quail breeding should include adequate droppings management policies to avoid potential sanitary issues related to fly productionFil: Battan Horenstein, Moira. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Instituto de Diversidad y Ecologia Animal; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; ArgentinaFil: Lynch Ianello, I.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinar de Biología Vegetal (p). Grupo Vinculado Centro de Relevamiento y Evaluacion de Recursos Agricolas y Naturales; ArgentinaFil: de Dió, B.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinar de Biología Vegetal (p). Grupo Vinculado Centro de Relevamiento y Evaluacion de Recursos Agricolas y Naturales; ArgentinaFil: Gleiser, Raquel M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinar de Biología Vegetal (p). Grupo Vinculado Centro de Relevamiento y Evaluacion de Recursos Agricolas y Naturales; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentin
Towards the fabrication of phosphorus qubits for a silicon quantum computer
The quest to build a quantum computer has been inspired by the recognition of
the formidable computational power such a device could offer. In particular
silicon-based proposals, using the nuclear or electron spin of dopants as
qubits, are attractive due to the long spin relaxation times involved, their
scalability, and the ease of integration with existing silicon technology.
Fabrication of such devices however requires atomic scale manipulation - an
immense technological challenge. We demonstrate that it is possible to
fabricate an atomically-precise linear array of single phosphorus bearing
molecules on a silicon surface with the required dimensions for the fabrication
of a silicon-based quantum computer. We also discuss strategies for the
encapsulation of these phosphorus atoms by subsequent silicon crystal growth.Comment: To Appear in Phys. Rev. B Rapid Comm. 5 pages, 5 color figure
Transgressing the moral economy: Wheelerism and management of the nationalised coal industry in Scotland
This article illuminates the links between managerial style and political economy in post-1945 Britain, and explores the origins of the 1984–1985 miners' strike, by examining in longer historical context the abrasive attitudes and policies of Albert Wheeler, Scottish Area Director of the National Coal Board (NCB). Wheeler built on an earlier emphasis on production and economic criteria, and his micro-management reflected pre-existing centralising tendencies in the industries. But he was innovative in one crucial aspect, transgressing the moral economy of the Scottish coalfield, which emphasised the value of economic security and changes by joint industrial agreement
Frequency-Invariant Representation of Interaural Time Differences in Mammals
Interaural time differences (ITDs) are the major cue for localizing low-frequency sounds. The activity of neuronal populations in the brainstem encodes ITDs with an exquisite temporal acuity of about . The response of single neurons, however, also changes with other stimulus properties like the spectral composition of sound. The influence of stimulus frequency is very different across neurons and thus it is unclear how ITDs are encoded independently of stimulus frequency by populations of neurons. Here we fitted a statistical model to single-cell rate responses of the dorsal nucleus of the lateral lemniscus. The model was used to evaluate the impact of single-cell response characteristics on the frequency-invariant mutual information between rate response and ITD. We found a rough correspondence between the measured cell characteristics and those predicted by computing mutual information. Furthermore, we studied two readout mechanisms, a linear classifier and a two-channel rate difference decoder. The latter turned out to be better suited to decode the population patterns obtained from the fitted model
The Bulgeless Seyfert/LINER Galaxy NGC 3367: Disk, Bar, Lopsidedness and Environment
NGC3367 is a nearby isolated active galaxy that shows a radio jet, a strong
bar and evidence of lopsidedness. We present a quantitative analysis of the
stellar and gaseous structure of the galaxy disk and a search for evidence of
recent interaction based on new UBVRI Halpha and JHK images and on archival
Halpha Fabry-Perot and HI VLA data. From a coupled 1D/2D GALFIT bulge/bar/disk
decomposition an (B/D ~ 0.07-0.1) exponential pseudobulge is inferred in all
the observed bands. A NIR estimate of the bar strength = 0.44
places NGC 3367 bar among the strongest ones. The asymmetry properties were
studied using (1) optical and NIR CAS indexes (2) the stellar (NIR) and gaseous
(Halpha, HI) A_1 Fourier mode amplitudes and (3) the HI integrated profile and
HI mean intensity distribution. While the average stellar component shows
asymmetry values close to the average found in the Local Universe for isolated
galaxies, the young stellar component and gas values are largely decoupled
showing significantly larger A_1 mode amplitudes suggesting that the gas has
been recently perturbed. Our search for (1) faint stellar structures in the
outer regions (up to u_R ~ 26 mag arcsec^{-2}), (2) (Halpha) star-forming
satellite galaxies and (3) regions with different colors (stellar populations)
along the disk all failed. Such an absence is interpreted using recent
numerical simulations to constrain a tidal event with an LMC like galaxy to
some dynamical times in the past or to a current very low mass, gas rich
accretion. We conclude that a cold accretion mode (gas and small/dark galaxies)
may be responsible of the nuclear activity and peculiar (young stars and gas)
morphology regardless of the highly isolated environment. Black hole growth in
bulgeless galaxies may be triggered by cosmic smooth mass accretion.Comment: 27 pages, 12 figures, accepted for publication in The Astronomical
Journa
BRCA1 promoter methylation and clinical outcomes in ovarian cancer: an individual patient data meta-analysis
BACKGROUND
BRCA1 methylation has been associated with homologous recombination deficiency, a biomarker of platinum sensitivity. Studies evaluating BRCA1-methylated tubal/ovarian cancer (OC) do not consistently support improved survival following platinum chemotherapy. We examine the characteristics of BRCA1-methylated OC in a meta-analysis of individual participant data.
METHODS
2636 participants' data across 15 studies were analyzed. BRCA1-methylated tumors were defined according to their original study. Associations between BRCA1 methylation and clinico-pathological characteristics were evaluated. The effects of methylation on overall survival (OS) and progression-free survival (PFS) were examined using mixed-effects models. All statistical tests were two-sided.
RESULTS
430 (16.3%) tumors were BRCA1-methylated. BRCA1 methylation was associated with younger age and advanced-stage high-grade serous OC. There were no survival differences between BRCA1-methylated and non-BRCA1-methylated OC (median PFS = 20.0 vs 18.5 months, HR = 1.01, 95% CI = 0.87-1.16, P=0.98; median OS = 46.6 vs 48.0 months, HR = 1.02, 95% CI = 0.87-1.18, P=0.96). Where BRCA1/2 mutations were evaluated (n = 1248), BRCA1 methylation displayed no survival advantage over BRCA1/2 intact (BRCA1/2 wild type non-BRCA1-methylated) OC. Studies used different methods to define BRCA1 methylation. Where BRCA1 methylation was determined using methylation-specific PCR and gel electrophoresis (n = 834), it was associated with improved survival (PFS: HR = 0.80, 95% CI = 0.66-0.97, P=0.02; OS: HR = 0.80, 95% CI = 0.63-1.00, P=0.05) on mixed-effects modelling.
CONCLUSION
BRCA1-methylated OC displays similar clinico-pathological features to BRCA1-mutated OC, but is not associated with survival. Heterogeneity within BRCA1 methylation assays influences associations. Refining these assays may better identify cases with silenced BRCA1 function and improved patient outcomes
A Large Sky Survey with MeerKAT
We discuss the ground-breaking science that will be possible with a wide area survey, using
the MeerKAT telescope, known as MeerKLASS (MeerKAT Large Area Synoptic Survey). The
current specifications of MeerKAT make it a great fit for cosmological applications, which require
large volumes. In particular, a large survey over ~4,000 deg^2 for ~4,000 hours will potentially
provide the first ever measurements of the baryon acoustic oscillations using the 21cm intensity
mapping technique, with enough accuracy to impose constraints on the nature of dark energy. The
combination with multi-wavelength data will give unique additional information, such as the first
constraints on primordial non-Gaussianity using the multi-tracer technique, as well as a better
handle on foregrounds and systematics. The survey will also produce a large continuum galaxy
sample down to a depth of 5 µJy in L-band, unmatched by any other concurrent telescope, which
will allow to study the large-scale structure of the Universe out to high redshifts. Finally, the same
survey will supply unique information for a range of other science applications, including a large
statistical investigation of galaxy clusters, and the discovery of rare high-redshift AGN that can be
used to probe the epoch of reionization as well as produce a rotation measure map across a huge
swathe of the sky. The MeerKLASS survey will be a crucial step on the road to using SKA1-MID
for cosmological applications, as described in the top priority SKA key science projects
The variation in acute and community service provision of care of the elderly services across the Scotland: Findings from the Scottish Care of Older People (SCoOP) National Audit initial scoping survey
We gratefully acknowledge the support of the British Geriatrics Society (BGS) in raising awareness of this work and the BGS Scotland Council for dissemination of the scoping survey. We also would like to thank Mr Tiberiu Pana, Mr Jesus Perdomo, Dr Maryam Barma and Dr Adrian Wood for their assistance with the project. We would also like to thank the SCoOP Steering Committee Members and Dr Claire Copeland (NHS Forth Valley) for their contribution. The SCoOP Steering Group includes: Dr Louise Beveridge (NHS Tayside), Professor Corri Black (University of Aberdeen), Ms Penny Bond (Healthcare Improvement Scotland), Dr Jennifer Burns (NHS Greater Glasgow and Clyde), Dr Tony Byrne (NHS Forth Valley), Dr Andrew Coull (NHS Lothian), Dr Alison Donaldson (University of Aberdeen), Dr Alice Einarsson (NHS Grampian), Professor Graham Ellis (NHS Lanarkshire, Glasgow Caledonian University and Co-Chair), Ms Karen Goudie(Healthcare Improvement Scotland) , Dr Graeme Hoyle (NHS Grampian), Dr Allan MacDonald (NHS Highland), Dr Christine McAlpine (NHS Greater Glasgow and Clyde), Dr Morven McElroy (NHS Greater Glasgow and Clyde), Professor Phyo Kyaw Myint (University of Aberdeen, Co-Chair), Dr Terence J Quinn (University of Glasgow), Professor Sir Lewis Ritchie (University of Aberdeen), Dr Susan Shenkin (University of Edinburgh), Dr Ralph Thomas (NHS Fife) and Dr Andrew Watt (NHS Ayrshire and Arran).Peer reviewedPublisher PD
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