162 research outputs found

    The Halo and Rings of the Planetary Nebula NGC 40 in the Mid-Infrared

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    We present imaging and spectroscopy of NGC 40 acquired using the Spitzer Space Telescope (Spitzer), and the Infrared Space observatory (ISO). These are used to investigate the nature of emission from the central nebular shell, from the nebular halo, and from the associated circumnebular rings. It is pointed out that a variety of mechanisms may contribute to the mid-infrared (MIR) fluxes, and there is evidence for a cool dust continuum, strong ionic transitions, and appreciable emission by polycyclic aromatic hydrocarbons (PAHs). Prior observations at shorter wavelengths also indicate the presence of warmer grains, and the possible contribution of H2 transitions. It is suggested that an apparent jet-like structure to the NE of the halo represents one of the many emission spokes that permeate the shell. The spokes are likely to be caused by the percolation of UV photons through a clumpy interior shell, whilst the jet-like feature is enhanced due to locally elevated electron densities; a result of interaction between NGC 40 and the interstellar medium. It is finally noted that the presence of the PAH, 21 microns and 30 microns spectral features testifies to appreciable C/O ratios within the main nebular shell. Such a result is consistent with abundance determinations using collisionally excited lines, but not with those determined using optical recombination linesComment: 13 pages, 8 figures, Accepted for publication in MNRAS. 37 pages in arXi

    The K2-3 system revisited: testing photoevaporation and core-powered mass loss with three small planets spanning the radius valley

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    Multi-planet systems orbiting M dwarfs provide valuable tests of theories of small planet formation and evolution. K2-3 is an early M dwarf hosting three small exoplanets (1.5-2.0 Earth radii) at distances of 0.07-0.20 AU. We measure the high-energy spectrum of K2-3 with HST/COS and XMM-Newton, and use empirically-driven estimates of Ly-alpha and extreme ultraviolet flux. We use EXOFASTv2 to jointly fit radial velocity, transit, and SED data. This constrains the K2-3 planet radii to 4% uncertainty and the masses of K2-3b and c to 13% and 30%, respectively; K2-3d is not detected in RV measurements. K2-3b and c are consistent with rocky cores surrounded by solar composition envelopes (mass fractions of 0.36% and 0.07%), H2O envelopes (55% and 16%), or a mixture of both. However, based on the high-energy output and estimated age of K2-3, it is unlikely that K2-3b and c retain solar composition atmospheres. We pass the planet parameters and high-energy stellar spectrum to atmospheric models. Dialing the high-energy spectrum up and down by a factor of 10 produces significant changes in trace molecule abundances, but not at a level detectable with transmission spectroscopy. Though the K2-3 planets span the small planet radius valley, the observed system architecture cannot be readily explained by photoevaporation or core-powered mass loss. We instead propose 1) the K2-3 planets are all volatile-rich, with K2-3d having a lower density than typical of super-Earths, and/or 2) the K2-3 planet architecture results from more stochastic processes such as planet formation, planet migration, and impact erosion.Comment: 15 pages, 7 figure, published in AJ, HLSPs at https://archive.stsci.edu/hlsp/mstarpanspe

    SOD2 polymorphisms: unmasking the effect of polymorphism on splicing

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    BACKGROUND: The SOD2 gene encodes an antioxidant enzyme, mitochondrial superoxide dismutase. SOD2 polymorphisms are of interest because of their potential roles in the modulation of free radical-mediated macromolecular damage during aging. RESULTS: We identified a new splice variant of SOD2 in human lymphoblastoid cell lines (LCLs). The alternatively spliced product was originally detected by exon trapping of a minigene in order to examine the consequences of an intronic polymorphism found upstream of exon 4 (nucleotide 8136, 10T vs 9T). Examination of the transcripts derived from the endogenous loci in five LCLs with or without the intron 3 polymorphism revealed low levels of an in-frame deletion of exon 4 that were different from those detected by the exon trap assay. This suggested that exon trapping of the minigene unmasked the effect of the 10T vs 9T polymorphism on the splicing of the adjacent exon. We also determined the frequencies of single nucleotide polymorphisms in a sample of US African-Americans and non-African-Americans ages 65 years and older who participated in the 1999 wave of the National Long Term Care Survey (NLTCS). Particularly striking differences between African-Americans and non-African-Americans were found for the frequencies of genotypes at the 10T/9T intron 3 polymorphism. CONCLUSION: Exon trapping can unmask in vitro splicing differences caused by a 10T/9T intron 3 polymorphism. Given the recent evidence that SOD2 is in a region on chromosome 6 linked to susceptibility to hypertension, it will be of interest to investigate possible associations of this polymorphism with cardiovascular disorders

    Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context

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    Long noncoding RNAs (lncRNAs) are commonly dys-regulated in tumors, but only a handful are known toplay pathophysiological roles in cancer. We inferredlncRNAs that dysregulate cancer pathways, onco-genes, and tumor suppressors (cancer genes) bymodeling their effects on the activity of transcriptionfactors, RNA-binding proteins, and microRNAs in5,185 TCGA tumors and 1,019 ENCODE assays.Our predictions included hundreds of candidateonco- and tumor-suppressor lncRNAs (cancerlncRNAs) whose somatic alterations account for thedysregulation of dozens of cancer genes and path-ways in each of 14 tumor contexts. To demonstrateproof of concept, we showed that perturbations tar-geting OIP5-AS1 (an inferred tumor suppressor) andTUG1 and WT1-AS (inferred onco-lncRNAs) dysre-gulated cancer genes and altered proliferation ofbreast and gynecologic cancer cells. Our analysis in-dicates that, although most lncRNAs are dysregu-lated in a tumor-specific manner, some, includingOIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergis-tically dysregulate cancer pathways in multiple tumorcontexts

    Pan-cancer Alterations of the MYC Oncogene and Its Proximal Network across the Cancer Genome Atlas

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    Although theMYConcogene has been implicated incancer, a systematic assessment of alterations ofMYC, related transcription factors, and co-regulatoryproteins, forming the proximal MYC network (PMN),across human cancers is lacking. Using computa-tional approaches, we define genomic and proteo-mic features associated with MYC and the PMNacross the 33 cancers of The Cancer Genome Atlas.Pan-cancer, 28% of all samples had at least one ofthe MYC paralogs amplified. In contrast, the MYCantagonists MGA and MNT were the most frequentlymutated or deleted members, proposing a roleas tumor suppressors.MYCalterations were mutu-ally exclusive withPIK3CA,PTEN,APC,orBRAFalterations, suggesting that MYC is a distinct onco-genic driver. Expression analysis revealed MYC-associated pathways in tumor subtypes, such asimmune response and growth factor signaling; chro-matin, translation, and DNA replication/repair wereconserved pan-cancer. This analysis reveals insightsinto MYC biology and is a reference for biomarkersand therapeutics for cancers with alterations ofMYC or the PMN

    Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas

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    This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin

    Spatial Organization and Molecular Correlation of Tumor-Infiltrating Lymphocytes Using Deep Learning on Pathology Images

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    Beyond sample curation and basic pathologic characterization, the digitized H&E-stained images of TCGA samples remain underutilized. To highlight this resource, we present mappings of tumorinfiltrating lymphocytes (TILs) based on H&E images from 13 TCGA tumor types. These TIL maps are derived through computational staining using a convolutional neural network trained to classify patches of images. Affinity propagation revealed local spatial structure in TIL patterns and correlation with overall survival. TIL map structural patterns were grouped using standard histopathological parameters. These patterns are enriched in particular T cell subpopulations derived from molecular measures. TIL densities and spatial structure were differentially enriched among tumor types, immune subtypes, and tumor molecular subtypes, implying that spatial infiltrate state could reflect particular tumor cell aberration states. Obtaining spatial lymphocytic patterns linked to the rich genomic characterization of TCGA samples demonstrates one use for the TCGA image archives with insights into the tumor-immune microenvironment

    Identification and thermochemical analysis of high-lignin feedstocks for biofuel and biochemical production

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    Background - Lignin is a highly abundant biopolymer synthesized by plants as a complex component of plant secondary cell walls. Efforts to utilize lignin-based bioproducts are needed. Results - Herein we identify and characterize the composition and pyrolytic deconstruction characteristics of high-lignin feedstocks. Feedstocks displaying the highest levels of lignin were identified as drupe endocarp biomass arising as agricultural waste from horticultural crops. By performing pyrolysis coupled to gas chromatography-mass spectrometry, we characterized lignin-derived deconstruction products from endocarp biomass and compared these with switchgrass. By comparing individual pyrolytic products, we document higher amounts of acetic acid, 1-hydroxy-2-propanone, acetone and furfural in switchgrass compared to endocarp tissue, which is consistent with high holocellulose relative to lignin. By contrast, greater yields of lignin-based pyrolytic products such as phenol, 2-methoxyphenol, 2-methylphenol, 2-methoxy-4-methylphenol and 4-ethyl-2-methoxyphenol arising from drupe endocarp tissue are documented. Conclusions - Differences in product yield, thermal decomposition rates and molecular species distribution among the feedstocks illustrate the potential of high-lignin endocarp feedstocks to generate valuable chemicals by thermochemical deconstruction

    Crop Updates 2002 - Farming Systems

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    This session covers forty one papers from different authors: INTRODUCTION 1. Future Farming Systems session for Crop Updates 2002 Peter Metcalf, FARMING SYSTEMS SUBPROGRAM MANAGER GRAINS PROGRAM Department of Agriculture 2. Perennial pastures in annual cropping systems: Lucerne and beyond, the ‘Big Picture’, Mike Ewing, Deputy CEO CRC for Plant-based Management of Dryland Salinity, Department of Agriculture 3. Perennial pastures in annual cropping systems: lucerne and beyond, Roy Latta and Keith Devenish, Department of Agriculture 4. Establishing Lucerne with a cover crop, Diana Fedorenko1, Clayton Butterly1, Chantelle Butterly1, Kim and Neil Diamond2, Stuart McAlpine2, Bill Bowden1, Jessica Johns3, 1Centre for Cropping Systems, Northam, 2Farmer, Buntine, 3Department of Agriculture 5. Overcropping: Chemical suppression of Lucerne, Terry Piper1, Diana Fedorenko1, Clayton Butterly1, Chantelle Butterly1, Stuart McAlpine2, Jessica Johns3, 1Centre for Cropping Systems, Northam, 2Farmer, Buntine, 3Department of Agriculture 6. Overcropping: Effect of Lucerne density on crop yield, Diana Fedorenko1, Bill Bowden1, Clayton Butterly1, Chantelle Butterly1, Stuart McAlpine2, Terry Piper1,1Centre for Cropping Systems, Department of Agriculture, Northam, 2Farmer, Buntine 7. Residual effect of weed management in the third year of Lucerne on the following wheat crop, Diana Fedorenko1, Clayton Butterly1, Chantelle Butterly1, Stuart McAlpine2,Terry Piper1, David Bowran1, Jessica Johns3,1Centre for Cropping Systems, Northam, 2Farmer, Buntine, 3Department of Agriculture 8. Production of Lucerne and serradella in four soil types, Diana Fedorenko1 Clayton Butterly1, Chantelle Butterly1, Robert Beard2 1Centre for Cropping Systems, Department of Agriculture, 2Farmer, Cunderdin 9. The effect of spray topping on newly established Lucerne, Keith Devenish, Agriculture Western Australia 10. Leakage from phase rotations involving Lucerne, Phil Ward, CSIRO Plant Industry 11. Fungal diseases present in Western Australian Lucerne crops, Dominie Wright and Nichole Burges, Department of Agriculture 12. Survey of Western Australian Lucerne stands reveals widespread virus infection, Roger Jones and Danae Harman, Crop Improvement Institute, Department of Agriculture, and Centre for Legumes in Mediterranean Agriculture, University of WA ANNUAL PASTURE SYSTEMS 13. The use of Twist Fungus as a biosecurity measure against Annual Ryegrass Toxicity (ARGT), Greg Shea, GrainGuard Coordinator and George Yan, Biological and Resource Technology 14.Limitations and opportunities for increasing water use by annual crops and pastures, David Tennant1, Phil Ward2and David Hall1 1Department of Agriculture, 2CSIRO, Plant Industries, Floreat Park 15. Developing pasture species mixtures for more productive and sustainable cropping systems – 2001 crop performance, Anyou Liu, Clinton Revell and Candy Hudson, Centre for Cropping Systems, Department of Agriculture 16. Developing pasture species mixtures for more productive and sustainable cropping systems – weed management in regenerating mixtures, Anyou Liu and Clinton Revell, Centre for Cropping Systems, Department of Agriculture 17. Aphid tolerance of annual pasture legumes, Andrew Blake, Natalie Lauritsen, Department of Agriculture 18. Selecting the right variety for phase pasture systems, Keith Devenish, Department of Agriculture 19. Responses of alternative annual pasture and forage legumes to challenge with infectious subterranean clover mottle virus, John Fosu-Nyarko, Roger Jones, Lisa Smith, Mike Jones and Geoff Dwyer, State Agricultural Biotechnology Centre and Centre for Bioinformatics and Biological Computing, Murdoch University, Department of Agriculture, and Centre for Legumes in Mediterranean Agriculture SOIL AND LAND MANAGEMENT 20. Nutrition in 2002: Decisions to be made as a result of last season, Bill Bowden,Western Australia Department of Agriculture 21. Profitability of deep banding lime, Michael O\u27Connell, Chris Gazey and David Gartner, Department of Agriculture 22. Lime efficiency percentage
the new measure of lime effectiveness for Western Australia, Amanda Miller, Department of Agriculture 23. Boron – should we be worried about it, Richard W. BellA, K. FrostA, Mike WongBand Ross BrennanC ASchool of Environmental Science, Murdoch University, BCSIRO Land and Water, CDepartment of Agriculture 24. Impact of claying and other amelioration on paddock profit, N.J. Blake1, G. McConnell2, D. Patabendige1and N. Venn11Department of Agriculture, 2PlanFarm P/L 25. Raised bed farming in the 2001 growing season, Derk Bakker, Greg Hamilton, Dave Houlbrooke and Cliff Spann, Department of Agriculture 26. Economics of tramline farming systems, Paul Blackwell and Bindi Webb, Department of Agriculture, Stuart McAlpine, Liebe Group. 27. Relay planting from Tramlines to increase water use and productivity os summer crops, Dr Paul Blackwell, Department of Agriculture, Neil and Kim Diamond, Buntine. Liebe Group 28.Evidence-based zone management of paddock variability to improve profits and environmental outcomes, M.T.F. WongA, D. PatabendigeB, G. LyleA and K. WittwerA ACSIRO Land and Water, BDepartment of Agriculture 29. How much soil water is lost over summer in sandy soils? Perry Dolling1, Senthold Asseng2, Ian Fillery2, Phil Ward2and Michael Robertson3 1University of Western Australia/Department of Agriculture Western Australia/CSIRO, 2CSIRO Plant Industry 3CSIRO Sustainable Ecosystems, Indooroopilly, Queensland FARMER DECISION SUPPORT AND ADOPTION 30. Economic comparisons of farming systems for the medium rainfall northern sandplain, No 1, Caroline Peek and David Rogers, Department of Agriculture 31. Sensitivity analysis of farming systems for the medium rainfall northern sandplain No 2, Caroline Peek and David Rogers, Department of Agriculture 32. Transition analysis of farming systems in the medium rainfall northern sandplain. No 3, Caroline Peek and David Rogers, Department of Agriculture 33. Implementing on-farm quality assurance, Peter Portmann, Manager Research and Development, The Grain Pool of Western Australia 34. On-farm research – principles of the ‘Test As You Grow’ kit, Jeff Russell, Department of Agriculture 35. Broadscale wheat variety comparisons featuring Wyalkatchem, Jeff Russell, Department of Agriculture 36. GrainGuardÔ - A biosecurity plan for the Canola Industry,Greg Shea Department of Agriculture 37. Are Western Australian broadacre farms efficient? Ben Henderson, University of Western Australia, Ross Kingwell, Department of Agriculture and University of Western Australia DISEASE MODELLING WORKSHOP 38. WORKSHOP: Pest and disease forecasts for you! An interactive forum, Tresslyn Walmsley, Jean Galloway, Debbie Thackray, Moin Salam and Art Diggle, Centre for Legumes in Mediterranean Agriculture and Department of Agriculture 39. Blackspot spread: Disease models are based in reality (Workshop paper 1), JeanGalloway,Department of Agriculture 40. Blackspot spread: Scaling-up field data to simulate ‘Baker’s farm’ (Workshop paper 2), Moin U. Salam, Jean Galloway, Art J. Diggle and William J. MacLeod, Department of Agriculture, Western Australia 41. A decision support system for control of aphids and CMV in lupin crops (Workshop paper 3), Debbie Thackray, Jenny Hawkes and Roger Jones, Centre for Legumes in Mediterranean Agriculture and Department of Agricultur

    Status Update and Interim Results from the Asymptomatic Carotid Surgery Trial-2 (ACST-2)

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    Objectives: ACST-2 is currently the largest trial ever conducted to compare carotid artery stenting (CAS) with carotid endarterectomy (CEA) in patients with severe asymptomatic carotid stenosis requiring revascularization. Methods: Patients are entered into ACST-2 when revascularization is felt to be clearly indicated, when CEA and CAS are both possible, but where there is substantial uncertainty as to which is most appropriate. Trial surgeons and interventionalists are expected to use their usual techniques and CE-approved devices. We report baseline characteristics and blinded combined interim results for 30-day mortality and major morbidity for 986 patients in the ongoing trial up to September 2012. Results: A total of 986 patients (687 men, 299 women), mean age 68.7 years (SD ± 8.1) were randomized equally to CEA or CAS. Most (96%) had ipsilateral stenosis of 70-99% (median 80%) with contralateral stenoses of 50-99% in 30% and contralateral occlusion in 8%. Patients were on appropriate medical treatment. For 691 patients undergoing intervention with at least 1-month follow-up and Rankin scoring at 6 months for any stroke, the overall serious cardiovascular event rate of periprocedural (within 30 days) disabling stroke, fatal myocardial infarction, and death at 30 days was 1.0%. Conclusions: Early ACST-2 results suggest contemporary carotid intervention for asymptomatic stenosis has a low risk of serious morbidity and mortality, on par with other recent trials. The trial continues to recruit, to monitor periprocedural events and all types of stroke, aiming to randomize up to 5,000 patients to determine any differential outcomes between interventions. Clinical trial: ISRCTN21144362. © 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved
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