421 results on '"H. McIntosh"'
Search Results
2. Optimized Photometric Redshifts for the Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey (CANDELS)
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Dritan Kodra, Brett H. Andrews, Jeffrey A. Newman, Steven L. Finkelstein, Adriano Fontana, Nimish Hathi, Mara Salvato, Tommy Wiklind, Stijn Wuyts, Adam Broussard, Nima Chartab, Christopher Conselice, M. C. Cooper, Avishai Dekel, Mark Dickinson, Henry C. Ferguson, Eric Gawiser, Norman A. Grogin, Kartheik Iyer, Jeyhan Kartaltepe, Susan Kassin, Anton M. Koekemoer, David C. Koo, Ray A. Lucas, Kameswara Bharadwaj Mantha, Daniel H. McIntosh, Bahram Mobasher, Camilla Pacifici, Pablo G. Pérez-González, and Paola Santini
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Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
We present the first comprehensive release of photometric redshifts (photo-z's) from the Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey (CANDELS) team. We use statistics based upon the Quantile-Quantile (Q--Q) plot to identify biases and signatures of underestimated or overestimated errors in photo-z probability density functions (PDFs) produced by six groups in the collaboration; correcting for these effects makes the resulting PDFs better match the statistical definition of a PDF. After correcting each group's PDF, we explore three methods of combining the different groups' PDFs for a given object into a consensus curve. Two of these methods are based on identifying the minimum f-divergence curve, i.e., the PDF that is closest in aggregate to the other PDFs in a set (analogous to the median of an array of numbers). We demonstrate that these techniques yield improved results using sets of spectroscopic redshifts independent of those used to optimize PDF modifications. The best photo-z PDFs and point estimates are achieved with the minimum f-divergence using the best 4 PDFs for each object (mFDa4) and the Hierarchical Bayesian (HB4) methods, respectively. The HB4 photo-z point estimates produced $\sigma_{\rm NMAD} = 0.0227/0.0189$ and $|\Delta z/(1+z)| > 0.15$ outlier fraction = 0.067/0.019 for spectroscopic and 3D-HST redshifts, respectively. Finally, we describe the structure and provide guidance for the use of the CANDELS photo-z catalogs, which are available at https://archive.stsci.edu/hlsp/candels., Comment: 35 pages, 19 figures, published in ApJ, data available at https://archive.stsci.edu/hlsp/candels
- Published
- 2022
- Full Text
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3. Exploring the Relationship Between Music and Emotions with Machine Learning
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Tyler H. McIntosh
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Cognitive science ,Music and emotion ,Psychology - Published
- 2021
4. Is Expenditure to Assess the Feasibility of Constructing or Acquiring Capital Assets Deductible?
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H McIntosh and John Prebble
- Abstract
No description supplied
- Published
- 2020
5. Deducting Expenditure to Assess the Feasibility of Constructing Capital Assets: Opinions from Inland Revenue, the High Court, and the Court of Appeal
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H McIntosh and John Prebble
- Abstract
No description supplied
- Published
- 2020
6. FDG PET-CT imaging for pre operative staging in patients with colorectal cancer
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David Weller, Francesca M Chappell, Julie Glanville, J Brush, Andrew G Renehan, Marshall Dozier, Fay Crawford, Malcolm G. Dunlop, and H McIntosh
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medicine.medical_specialty ,Colorectal cancer ,business.industry ,medicine ,Fdg pet ct ,In patient ,Pharmacology (medical) ,Radiology ,medicine.disease ,business ,Pre operative staging - Published
- 2020
7. Supplementation with Brazil nuts and green tea extract regulates targeted biomarkers related to colorectal cancer risk in humans
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Graeme P. Young, Libby Bambaca, Richard K. Le Leu, Graeme H. McIntosh, Ying Hu, Geetha Gopalsamy, Ross A. McKinnon, Roshini Somashekar, and Xing Q. Meng
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Male ,Risk ,0301 basic medicine ,Food Handling ,Colorectal cancer ,Medicine (miscellaneous) ,Inflammation ,Green tea extract ,Pharmacology ,medicine.disease_cause ,Camellia sinensis ,Selenium ,03 medical and health sciences ,0302 clinical medicine ,food ,Functional Food ,South Australia ,Biomarkers, Tumor ,medicine ,Anticarcinogenic Agents ,Humans ,Nuts ,Intestinal Mucosa ,Aged ,Nutrition and Dietetics ,Plant Extracts ,business.industry ,Selenoprotein P ,Rectum ,Methylation ,Middle Aged ,medicine.disease ,food.food ,Plant Leaves ,030104 developmental biology ,030220 oncology & carcinogenesis ,Dietary Supplements ,Bertholletia ,DNMT1 ,Feasibility Studies ,Female ,medicine.symptom ,Colorectal Neoplasms ,business ,Carcinogenesis ,Brazil nut - Abstract
Se and green tea have been shown in epidemiological, observational and preclinical studies to be inversely related to the risk of developing colorectal cancer (CRC). However, there are limited studies to evaluate their regulatory effects on genes/proteins that relate to CRC oncogenesis in human subjects, such as selenoproteins, WNT signalling pathway, inflammation and methylation. This study examined the effects of supplementation of Se using Brazil nuts and green tea extract (GTE) capsules, alone and in combination, on targeted biomarkers. In total, thirty-two volunteers (>50 years of age) with plasma Se≤1·36 µmol/l were randomised to one of three treatment groups: nine to Se (approximately 48 µg/d) as six Brazil nuts, eleven to four GTE capsules (800 mg (-)-epigallocatechin-3-gallate) and twelve to a combination of Brazil nuts and GTE. Blood and rectal biopsies were obtained before and after each intervention. Plasma Se levels, rectal selenoprotein P (SePP) and β-catenin mRNA increased significantly in subjects consuming Brazil nuts alone or in combination, whereas rectal DNA methyltransferase (DNMT1) and NF-κB mRNA were reduced significantly in subjects consuming GTE alone or in combination. None of the interventions significantly affected rectal acetylated histone H3 or Ki-67 expression at the protein level or plasma C-reactive protein. Effects of the combination of Brazil nuts and GTE did not differ from what would be expected from either agent alone. In conclusion, supplementation of Brazil nuts and/or GTE regulates targeted biomarkers related to CRC oncogenesis, specifically genes associated with selenoproteins (SePP), WNT signalling (β-catenin), inflammation (NF-κB) and methylation (DNMT1). Their combination does not appear to provide additional effects compared with either agent alone.
- Published
- 2016
8. Studying the Physical Properties of Tidal Features I. Extracting Morphological Substructure in CANDELS Observations and VELA Simulations
- Author
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Camilla Pacifici, Anton M. Koekemoer, Luther Landry, Rubyet Evan, Vicente Rodriguez-Gomez, Raymond C. Simons, Nimish P. Hathi, Gregory F. Snyder, Cody Ciaschi, Joel R. Primack, Daniel Ceverino, Daniel H. McIntosh, Scott E. Thompson, Henry C. Ferguson, Yicheng Guo, Eric F. Bell, Marc Rafelski, Kameswara Bharadwaj Mantha, Logan B. Fries, and Elizabeth J. McGrath
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Physics ,010308 nuclear & particles physics ,James Webb Space Telescope ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Vela ,Residual ,Viewing angle ,01 natural sciences ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Galaxy formation and evolution ,Surface brightness ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Parametric statistics - Abstract
The role of major mergers in galaxy evolution remains a key open question. Existing empirical merger identification methods use non-parametric and subjective visual classifications which can pose systematic challenges to constraining merger histories. As a first step towards overcoming these challenges, we develop and share publicly a new Python-based software tool that identifies and extracts the flux-wise and area-wise significant contiguous regions from the model-subtracted "residual" images produced by popular parametric light-profile fitting tools (e.g., GALFIT). Using Hubble Space Telescope ($HST$) $H$-band single-S\'ersic residual images of $17$ CANDELS galaxies, we demonstrate the tool's ability to measure the surface brightness and improve the qualitative identification of a variety of common residual features (disk structures, spiral substructures, plausible tidal features, and strong gravitational arcs). We test our method on synthetic $HST$ observations of a $z\sim 1.5$ major merger from the VELA hydrodynamic simulations. We extract $H$-band residual features corresponding to the birth, growth, and fading of tidal features during different stages and viewing orientations at CANDELS depths and resolution. We find that the extracted features at shallow depths have noisy visual appearance and are susceptible to viewing angle effects. For a VELA $z\sim 3$ major merger, we find that James Webb Space Telescope NIRCam observations can probe high-redshift tidal features with considerable advantage over existing $HST$ capabilities. Further quantitative analysis of plausible tidal features extracted with our new software hold promise for the robust identification of hallmark merger signatures and corresponding improvements to merger rate constraints., Comment: 18 pages, 11 Figures, and accepted for publication in MNRAS. The data products discussed in this paper along with the software are publicly available at https://github.com/AgentM-GEG/residual_feature_extraction
- Published
- 2019
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9. The relationship between star formation activity and galaxy structural properties in CANDELS and a semi-analytic model
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Edward N. Taylor, P. Kurczynski, Sandra M. Faber, Anton M. Koekemoer, Ryan Brennan, Guillermo Barro, Stijn Wuyts, Rachel S. Somerville, Daniel H. McIntosh, Viraj Pandya, Henry C. Ferguson, Eric F. Bell, Avishai Dekel, Asa F. L. Bluck, Jeffrey A. Newman, and Joel R. Primack
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FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Galaxy merger ,Disc galaxy ,01 natural sciences ,0103 physical sciences ,Galaxy formation and evolution ,Interacting galaxy ,010303 astronomy & astrophysics ,Lenticular galaxy ,Astrophysics::Galaxy Astrophysics ,Physics ,Galaxies: bulges ,Galaxies: star formation ,010308 nuclear & particles physics ,Star formation ,Galaxies: evolution ,Astronomy ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Galaxies: interactions ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,bulges ,Quasars: super-massive black holes ,Galaxies: star formation [Galaxies] ,Elliptical galaxy - Abstract
Monthly Notices of the Royal Astronomical Society, 465 (1), ISSN:0035-8711, ISSN:1365-2966, ISSN:1365-8711
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- 2016
10. Beyond spheroids and discs: classifications of CANDELS galaxy structure at 1.4 <z< 2 via principal component analysis
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Conor McPartland, Jeyhan S. Kartaltepe, Anton M. Koekemoer, Casey Papovich, Jennifer M. Lotz, Daniel H. McIntosh, Norman A. Grogin, Shoubaneh Hemmati, Michael Peth, Peter E. Freeman, Joel R. Primack, Yicheng Guo, Dale D. Kocevski, S. Alireza Mortazavi, Gregory F. Snyder, Guillermo Barro, Hooshang Nayyeri, and Raymond C. Simons
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Physics ,010308 nuclear & particles physics ,Star formation ,media_common.quotation_subject ,Structure (category theory) ,Astronomy ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Astrophysics - Astrophysics of Galaxies ,01 natural sciences ,Asymmetry ,Galaxy ,Space and Planetary Science ,Bulge ,0103 physical sciences ,Principal component analysis ,010303 astronomy & astrophysics ,Lenticular galaxy ,Astrophysics::Galaxy Astrophysics ,Spiral ,media_common - Abstract
Important but rare and subtle processes driving galaxy morphology and star-formation may be missed by traditional spiral, elliptical, irregular or S\'ersic bulge/disk classifications. To overcome this limitation, we use a principal component analysis of non-parametric morphological indicators (concentration, asymmetry, Gini coefficient, $M_{20}$, multi-mode, intensity and deviation) measured at rest-frame $B$-band (corresponding to HST/WFC3 F125W at 1.4 $< z 10^{10} M_{\odot}$) galaxy morphologies. Principal component analysis (PCA) quantifies the correlations between these morphological indicators and determines the relative importance of each. The first three principal components (PCs) capture $\sim$75 per cent of the variance inherent to our sample. We interpret the first principal component (PC) as bulge strength, the second PC as dominated by concentration and the third PC as dominated by asymmetry. Both PC1 and PC2 correlate with the visual appearance of a central bulge and predict galaxy quiescence. PC1 is a better predictor of quenching than stellar mass, as as good as other structural indicators (S\'ersic-n or compactness). We divide the PCA results into groups using an agglomerative hierarchical clustering method. Unlike S\'ersic, this classification scheme separates compact galaxies from larger, smooth proto-elliptical systems, and star-forming disk-dominated clumpy galaxies from star-forming bulge-dominated asymmetric galaxies. Distinguishing between these galaxy structural types in a quantitative manner is an important step towards understanding the connections between morphology, galaxy assembly and star-formation., Comment: 31 pages, 24 figures, accepted for publication in MNRAS
- Published
- 2016
11. Hemodynamics of the renal artery ostia with implications for their structural development and efficiency of flow
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Mesude Ozturk, Dimitrios V. Papavassiliou, Edgar A. O'Rear, William H. McIntosh, and Linden A. Down
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Models, Anatomic ,Pressure drop ,Physics ,Cardiac output ,Physiology ,Hemodynamics ,Models, Cardiovascular ,Geometry ,Blood flow ,Curvature ,Renal Artery ,Physiology (medical) ,medicine.artery ,medicine ,Shear stress ,Humans ,Computer Simulation ,Cardiac Output ,Renal artery ,Fillet (mechanics) ,Aorta ,Blood Flow Velocity ,Dimensionless quantity - Abstract
BACKGROUND Energy losses at tube or blood vessel orifices depend on the extent of flare as measured by the dimensionless ratio of the fillet radius of curvature to diameter (r/D). OBJECTIVE The goal of this study was to assess the effect of ostial fillet radii on energy losses at the aorta-renal artery junctions since as much as a quarter of cardiac output passes through the kidneys. METHOD Pressure loss coefficients K for the renal artery ostia as a function of r/D have been determined for representative anatomical variants using finite volume simulations. Estimates of fillet radii in humans from image analysis were employed in simulations for comparison of loss coefficients. RESULTS Values for K drop 45% as r/D increases over the range 0-1.3. Image analysis indicates that the ostia are not symmetric in humans with (r/D)superior much larger than (r/D)inferior. Simulations show the loss coefficient depends almost entirely on the superior fillet radius. CONCLUSIONS Superior fillet radii for both renal arteries are similar to the optimal value to reduce energy losses while the inferior radii are not. Ostial asymmetry may have been induced by higher levels of shear stress present on the superior portion of a developing symmetric ostium of small r/D.
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- 2015
12. Characterization of Lepidopteran Cell Lines by Isoelectric Focusing and Phosphoglucoisomerase*
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Carlo M. Ignoffo and Arthur H. McIntosh
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Biochemistry ,Isoelectric focusing ,Cell culture ,Chemistry ,Characterization (materials science) - Published
- 2018
13. Production of Baculoviruses for Insect Control Using Cell Culture*
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Cynthia L. Goodman and Arthur H. McIntosh
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Cell culture ,media_common.quotation_subject ,Production (economics) ,Insect ,Biology ,media_common ,Cell biology - Published
- 2018
14. Specificity of Baculoviruses*
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H McIntosh Arthur and J Grasela James
- Subjects
Biology - Published
- 2018
15. CANDELS: Elevated Black Hole Growth in the Progenitors of Compact Quiescent Galaxies at z~2
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Anton M. Koekemoer, Paola Santini, Joshua A. Young, Omar Almaini, Dale D. Kocevski, Norman A. Grogin, Henry C. Ferguson, Elizabeth J. McGrath, Guillermo Barro, Pablo Guillermo Pérez González, Antonis Georgakakis, Jennifer L. Donley, S. M. Faber, Jonathan R. Trump, Arjen van der Wel, Stijn Wuyts, Janine Pforr, Matthew Hawkins, Nimish P. Hathi, Rachel S. Somerville, Joel R. Primack, Avishai Dekel, Christopher J. Conselice, Bahram Mobasher, Mauro Giavalisco, David M. Alexander, Francesca Civano, Christina C. Williams, David C. Koo, Daniel H. McIntosh, Haojing Yan, Kirpal Nandra, Guenther Hasinger, and Mauro Stefanon
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ACTIVE GALACTIC NUCLEI ,Active galactic nucleus ,PHASE-3 BILLION YEARS ,Astrophysics::High Energy Astrophysical Phenomena ,Population ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,HIGH-REDSHIFT GALAXIES ,Extended Groth Strip ,0103 physical sciences ,STAR-FORMING GALAXIES ,Galaxy formation and evolution ,SOURCE IDENTIFICATION ,education ,ELLIPTIC ,010303 astronomy & astrophysics ,evolution [galaxies] ,Astrophysics::Galaxy Astrophysics ,Physics ,education.field_of_study ,Supermassive black hole ,010308 nuclear & particles physics ,Astronomy and Astrophysics ,DEEP SURVEY ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Redshift ,galaxies [X-rays] ,GALAXIES ,Black hole ,EXTENDED GROTH STRIP ,Physics and Astronomy ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,active [galaxies] ,STELLAR-MASS ,INSIDE-OUT - Abstract
We examine the fraction of massive ($M_{*}>10^{10} M_{\odot}$), compact star-forming galaxies (cSFGs) that host an active galactic nucleus (AGN) at $z\sim2$. These cSFGs are likely the direct progenitors of the compact quiescent galaxies observed at this epoch, which are the first population of passive galaxies to appear in large numbers in the early Universe. We identify cSFGs that host an AGN using a combination of Hubble WFC3 imaging and Chandra X-ray observations in four fields: the Chandra Deep Fields, the Extended Groth Strip, and the UKIDSS Ultra Deep Survey field. We find that $39.2^{+3.9}_{-3.6}$\% (65/166) of cSFGs at $1.4, Comment: Published in the Astrophysical Journal
- Published
- 2017
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16. Arm and interarm abundance gradients in CALIFA spiral galaxies
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A. de Lorenzo-Cáceres, Lluís Galbany, R. García-Benito, Yago Ascasibar, Tomás Ruiz-Lara, Angel R. Lopez-Sanchez, D. Mast, L. Costantin, L. Sánchez-Menguiano, R. A. Marino, Cristina Catalán-Torrecilla, Victor P. Debattista, C. J. Walcher, Patricia Sanchez-Blazquez, Oscar Cavichia, C. Kehrig, M. Cano-Díaz, Jairo Méndez-Abreu, Daniel H. McIntosh, Mercedes Mollá, I. Pérez, Estrella Florido, Joss Bland-Hawthorn, Sebastián F. Sánchez, R. M. González Delgado, I. Márquez, Ministerio de Economía, Industria y Competitividad (España), Junta de Andalucía, Consejo Nacional de Ciencia y Tecnología (México), National Science Foundation (US), Swiss National Science Foundation, and European Research Council
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Astrofísica ,Galaxies: abundances ,Galaxies: evolution ,Galaxies: ISM ,Galaxies: spiral ,Techniques: imaging spectroscopy ,Techniques: spectroscopic ,Astronomy and Astrophysics ,Space and Planetary Science ,Ciencias Físicas ,FOS: Physical sciences ,abundances [Galaxies] ,F500 ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Disc galaxy ,01 natural sciences ,spectroscopic [Techniques] ,purl.org/becyt/ford/1 [https] ,Abundance (ecology) ,0103 physical sciences ,ISM [Galaxies] ,Field spectroscopy ,010303 astronomy & astrophysics ,Spiral ,Astrophysics::Galaxy Astrophysics ,Physics ,spiral [Galaxies] ,Spiral galaxy ,010308 nuclear & particles physics ,F510 ,imaging spectroscopy [Techniques] ,Design systems ,Chemical distribution ,purl.org/becyt/ford/1.3 [https] ,evolution [Galaxies] ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Astronomía ,Astrophysics of Galaxies (astro-ph.GA) ,CIENCIAS NATURALES Y EXACTAS - Abstract
Spiral arms are the most singular features in disc galaxies. These structures can exhibit different patterns, namely grand design and flocculent arms, with easily distinguishable characteristics. However, their origin and the mechanisms shaping them are unclear. The overall role of spirals in the chemical evolution of disc galaxies is another unsolved question. In particular, it has not been fully explored if the H ii regions of spiral arms present different properties from those located in the interarm regions. Here we analyse the radial oxygen abundance gradient of the arm and interarm star forming regions of 63 face-on spiral galaxies using CALIFA Integral Field Spectroscopy data. We focus the analysis on three characteristic parameters of the profile: slope, zero-point, and scatter. The sample is morphologically separated into flocculent versus grand design spirals and barred versus unbarred galaxies. We find subtle but statistically significant differences betweenthe arm and interarm distributions for flocculent galaxies, suggesting that the mechanisms generating the spiral structure in these galaxies may be different to those producing grand design systems, for which no significant differences are found. We also find small differences in barred galaxies, not observed in unbarred systems, hinting that bars may affect the chemical distribution of these galaxies but not strongly enough as to be reflected in the overall abundance distribution. In light of these results, we propose bars and flocculent structure as two distinct mechanisms inducing differences in the abundance distribution between arm and interarm star forming regions.© ESO, 2017., We acknowledge financial support from the Spanish Ministerio de Economia y Competitividad (MINECO) via grants AYA2012-31935 and AYA2014-53506-P, and from the >Junta de Andalucia> local government through the FQM-108 project. We also acknowledge support from the ConaCyt funding program 180125 and DGAPA IA100815. V.P.D. is supported by STFC Consolidated grant #ST/M000877/1. V.P.D. acknowledges being a part of the network supported by the COST Action TD1403 >Big Data Era in Sky and Earth Observation>. L.G. was supported in part by the US National Science Foundation under Grant AST-1311862. R.A.M. acknowledges support from the Swiss National Science Foundation. J.M.A. acknowledges support from the European Research Council Starting Grant (SEDmorph; P.I. V. Wild) and MINECO through the grant AYA2013-43188-P. I.M. acknowledges support from the Junta de Andalucia through project TIC114, and the MINECO through projects AYA2013-42227-P and AYA2016-76682C3-1-P. Y.A. is financially supported by the Ramon y Cajal programme (contract RyC-2011-09461) and project AYA2016-79724-C4-1-P from the Spanish MINECO, as well as the exchange programme SELGIFS FP7-PEOPLE-2013-IRSES-612701 funded by the EU. R.M.G.D. acknowledges support from the Spanish grant AYA2010-15081, and from the >Junta de Andalucia> FQ1580 project.
- Published
- 2017
17. A new population of recently quenched elliptical galaxies in the SDSS
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C. Wagner, Anna Pasquali, Andrew Cooper, Allison M. Christian, Tim Haines, Anna Gallazzi, Frank C. van den Bosch, Dušan Kereš, Daniel H. McIntosh, Justin Mann, and Eric F. Bell
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Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,media_common.quotation_subject ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Spectral line ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,media_common ,Physics ,Number density ,010308 nuclear & particles physics ,Center (category theory) ,Astronomy ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Universe ,Galaxy ,Space and Planetary Science ,Sky ,Astrophysics of Galaxies (astro-ph.GA) ,Elliptical galaxy ,Halo ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We use the Sloan Digital Sky Survey to investigate the properties of massive elliptical galaxies in the local Universe (z\leq0.08) that have unusually blue optical colors. Through careful inspection, we distinguish elliptical from non-elliptical morphologies among a large sample of similarly blue galaxies with high central light concentrations (c_r\geq2.6). These blue ellipticals comprise 3.7 per cent of all c_r\geq2.6 galaxies with stellar masses between 10^10 and 10^11 h^{-2} {\rm M}_{\sun}. Using published fiber spectra diagnostics, we identify a unique subset of 172 non-star-forming ellipticals with distinctly blue urz colors and young (< 3 Gyr) light-weighted stellar ages. These recently quenched ellipticals (RQEs) have a number density of 2.7-4.7\times 10^{-5}\,h^3\,{\rm Mpc}^{-3} and sufficient numbers above 2.5\times10^{10} h^{-2} {\rm M}_{\sun} to account for more than half of the expected quiescent growth at late cosmic time assuming this phase lasts 0.5 Gyr. RQEs have properties that are consistent with a recent merger origin (i.e., they are strong `first-generation' elliptical candidates), yet few involved a starburst strong enough to produce an E+A signature. The preferred environment of RQEs (90 per cent reside at the centers of < 3\times 10^{12}\,h^{-1}{\rm M}_{\sun} groups) agrees well with the `small group scale' predicted for maximally efficient spiral merging onto their halo center and rules out satellite-specific quenching processes. The high incidence of Seyfert and LINER activity in RQEs and their plausible descendents may heat the atmospheres of small host halos sufficiently to maintain quenching., 26 pages, 9 figures. Revised version; accepted for publication in MNRAS
- Published
- 2014
18. GEMS: The surface brightness and surface mass density evolution of disk galaxies
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Andrea Borch, Daniel H. McIntosh, Chien Y. Peng, Rachel S. Somerville, John A. R. Caldwell, Knud Jahnke, Catherine Heymans, Lutz Wisotzki, Steven V. W. Beckwith, Klaus Meisenheimer, Hans-Walter Rix, B. Haeussler, Marco Barden, Sebastián F. Sánchez, Christian Wolf, Eric F. Bell, and Shardha Jogee
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Physics ,Institut für Physik und Astronomie ,Astronomy and Astrophysics ,Astrophysics ,Radius ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Virial theorem ,Redshift ,Galaxy ,Disk size ,Space and Planetary Science ,Halo ,Astrophysics::Earth and Planetary Astrophysics ,Scaling ,Astrophysics::Galaxy Astrophysics - Abstract
We combine HST imaging from the GEMS ( Galaxy Evolution from Morphologies and SEDs) survey with photometric redshifts from COMBO-17 to explore the evolution of disk-dominated galaxies since z less than or similar to 1.1. The sample is composed of all GEMS galaxies with Sersic indices n < 2.5, derived from fits to the galaxy images. We account fully for selection effects through careful analysis of image simulations; we are limited by the depth of the redshift and HST data to the study of galaxies with M-V less than or similar to -20, or equivalently, log (M/M-circle dot) greater than or similar to 10. We find strong evolution in the magnitude-size scaling relation for galaxies with M-V less than or similar to -20, corresponding to a brightening of similar to 1 mag arcsec(-2) in rest-frame V band by z similar to 1. Yet disks at a given absolute magnitude are bluer and have lower stellar mass-to-light ratios at z similar to 1 than at the present day. As a result, our findings indicate weak or no evolution in the relation between stellar mass and effective disk size for galaxies with log (M/M-circle dot) greater than or similar to 10 over the same time interval. This is strongly inconsistent with the most naive theoretical expectation, in which disk size scales in proportion to the halo virial radius, which would predict that disks are a factor of 2 denser at fixed mass at z similar to 1. The lack of evolution in the stellar mass-size relation is consistent with an "inside-out'' growth of galaxy disks on average (galaxies increasing in size as they grow more massive), although we cannot rule out more complex evolutionary scenarios
- Published
- 2016
19. Reference gene selection and RNA preservation protocol in the cat flea, Ctenocephalides felis, for gene expression studies
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Erich W. Zinser, Ewan M. Campbell, Debra J. Woods, Catriona H. Mcintosh, John Baird, and Alan S. Bowman
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0106 biological sciences ,0301 basic medicine ,Veterinary medicine ,Cat flea ,Preservation, Biological ,01 natural sciences ,03 medical and health sciences ,Ribosomal protein ,Reference genes ,Gene expression ,Animals ,Ctenocephalides ,Genetics ,biology ,Felis ,Gene Expression Profiling ,RNA ,Reference Standards ,biology.organism_classification ,010602 entomology ,030104 developmental biology ,Infectious Diseases ,Animal Science and Zoology ,Parasitology ,PEST analysis ,Entomology - Abstract
SUMMARYThe cat flea, Ctenocephalides felis, is a major pest species on companion animals thus of significant importance to the animal health industry. The aim of this study was to develop sampling and storage protocols and identify stable reference genes for gene expression studies to fully utilize the growing body of molecular knowledge of C. felis. RNA integrity was assessed in adult and larvae samples, which were either pierced or not pierced and stored in RNAlater at ambient temperature. RNA quality was maintained best in pierced samples, with negligible degradation evident after 10 days. RNA quality from non-pierced samples was poor within 3 days. Ten candidate reference genes were evaluated for their stability across four group comparisons (developmental stages, genders, feeding statuses and insecticide-treatment statuses). Glyceraldehyde 3 phosphate dehydrogenase (GAPDH), 60S ribosomal protein L19 (RPL19) and elongation factor-1α (Ef) were ranked highly in all stability comparisons, thus are recommended as reference genes under similar conditions. Employing just two of these three stable reference genes was sufficient for accurate normalization. Our results make a significant contribution to the future of gene expression studies in C. felis, describing validated sample preparation procedures and reference genes for use in this common pest.
- Published
- 2016
20. Gene knockdown by RNA interference in the cat flea (Ctenocephalides felis): Utilisingde novotranscriptome data for developing drug target identification strategies
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Catriona H McIntosh
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Gene knockdown ,biology ,RNA interference ,Felis ,Cat flea ,Drug target ,Identification (biology) ,biology.organism_classification ,Virology ,Ctenocephalides - Published
- 2016
21. Handsearching did not yield additional unique FDG-PET diagnostic test accuracy studies compared with electronic searches: a preliminary investigation
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Marshall Dozier, Maria Cikalo, H McIntosh, Julie Glanville, and Fay Crawford
- Subjects
medicine.medical_specialty ,Pathology ,Systematic review ,business.industry ,Medicine ,Review Literature as Topic ,Diagnostic test ,Medical physics ,business ,Education - Abstract
We explored the value of handsearching to identify diagnostic test accuracy (DTA) studies to inform systematic reviews of DTA. Handsearching was conducted alongside a systematic review of the DTA of 18F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) for colorectal cancer. Ten journals, identified by frequency analysis of studies from six imaging reviews, were handsearched for reports of DTA studies. The numbers of studies identified by handsearching and by database searching were compared. A total of 573 journal issues from ten journals were handsearched in 185 h. A total of 936 potential reports of DTA studies were identified: 25 were relevant to the FDG PET-CT review. 7/25 FDG PET-CT papers had not been identified by database searches. No papers met the systematic review inclusion criteria. The FDG-PET systematic review included 30 papers, from 24 different journals. Handsearching two of those journals identified 211 potential reports of DTA studies for all topics and 18 for FDG PET-CT. Handsearching identified previously unseen papers but did not yield unique relevant DTA studies for the specific review. DTA imaging studies are widely distributed, and it may be more efficient to choose journals to handsearch after the identification of some relevant studies. Copyright © 2012 John Wiley & Sons, Ltd.
- Published
- 2012
22. galapagos: from pixels to parameters
- Author
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Daniel H. McIntosh, Boris Häußler, Marco Barden, Chien Y. Peng, and Yicheng Guo
- Subjects
Physics ,Pixel ,010308 nuclear & particles physics ,Process (computing) ,Sorting ,Astronomy and Astrophysics ,Context (language use) ,Object (computer science) ,computer.software_genre ,01 natural sciences ,Data set ,Set (abstract data type) ,Space and Planetary Science ,0103 physical sciences ,Table (database) ,Data mining ,010303 astronomy & astrophysics ,computer - Abstract
Context. To automate source detection, two-dimensional light-profile S´ ersic modelling and catalogue compilation in large survey applications, we introduce a new code Galapagos, Galaxy Analysis over Large Areas: Parameter Assessment by GALFITting Objects from SExtractor. Aims. Based on a single setup, Galapagos can process a complete set of survey images. It detects sources in the data, estimates a local sky background, cuts postage stamp images for all sources, prepares object masks, performs Sfitting including neighbours and compiles all objects in a final output catalogue. Methods. For the initial source detection Galapagos applies SExtractor, while Galfit is incorporated for modelling Sprofiles. It measures the background sky involved in the S´ ersic fitting by means of a flux growth curve. Galapagos determines postage stamp sizes based on SExtractor shape parameters. In order to obtain precise model parameters Galapagos incorporates a complex sorting mechanism and makes use of modern CPU's multiplexing capabilities. It combines SExtractor and Galfit data in a single out- put table. When incorporating information from overlapping tiles, Galapagos automatically removes multiple entries from identical sources. Galapagos is programmed in the Interactive Data Language, IDL. Results. We test the stability and the ability to properly recover structural parameters extensively with artificial image simulations. Moreover, we apply Galapagos successfully to the STAGES data set. For one-orbit HST data, a single 2.2 GHz CPU processes about 1000 primary sources per 24 hours. Note that Galapagos results depend critically on the user-defined parameter setup. This paper provides useful guidelines to help the user make sensible choices.
- Published
- 2012
23. A new automatic method to identify galaxy mergers - I. Description and application to the Space Telescope A901/902 Galaxy Evolution Survey★
- Author
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Alfonso Aragón-Salamanca, Daniel H. McIntosh, Meghan E. Gray, Knud Jahnke, Fabio D. Barazza, Carlos D. Hoyos, Eric F. Bell, David T. Maltby, Christian Wolf, Asmus Boehm, Kyle Lane, Boris Häussler, and S. Jogee
- Subjects
Physics ,education.field_of_study ,010308 nuclear & particles physics ,Population ,Magnitude (mathematics) ,Astronomy and Astrophysics ,Sample (statistics) ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Galaxy merger ,Residual ,01 natural sciences ,Galaxy ,Space and Planetary Science ,0103 physical sciences ,Cluster (physics) ,Fraction (mathematics) ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
We present an automatic method to identify galaxy mergers using the morphological information contained in the residual images of galaxies after the subtraction of a Sersic model. The removal of the bulk signal from the host galaxy light is done with the aim of detecting the fainter minor mergers. The specific morphological parameters that are used in the merger diagnostic suggested here are the Residual Flux Fraction and the asymmetry of the residuals. The new diagnostic has been calibrated and optimized so that the resulting merger sample is very complete. However, the contamination by non-mergers is also high. If the same optimization method is adopted for combinations of other structural parameters such as the CAS system, the merger indicator we introduce yields merger samples of equal or higher statistical quality than the samples obtained through the use of other structural parameters. We explore the ability of the method presented here to select minor mergers by identifying a sample of visually classified mergers that would not have been picked up by the use of the CAS system, when using its usual limits. Given the low prevalence of mergers among the general population of galaxies and the optimization used here, we find that the merger diagnostic introduced in this work is best used as a negative merger test, i.e., it is very effective at selecting non-merging galaxies. As with all the currently available automatic methods, the sample of merger candidates selected is contaminated by non-mergers, and further steps are needed to produce a clean sample. This merger diagnostic has been developed using the HST/ACS F606W images of the A901/02 cluster (z=0.165) obtained by the STAGES team. In particular, we have focused on a mass and magnitude limited sample (log M/M_{O}>9.0, R_{Vega}
- Published
- 2011
24. Baculovirus infection influences host protein expression in two established insect cell lines
- Author
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Holly J. R. Popham, Cynthia L. Goodman, Arthur H. McIntosh, and James J. Grasela
- Subjects
Baculoviridae ,Physiology ,Sequence analysis ,viruses ,Cell ,Moths ,Cell Line ,medicine ,Animals ,Electrophoresis, Gel, Two-Dimensional ,biology ,Heliothis virescens ,Gene Expression Profiling ,fungi ,Computational Biology ,Sequence Analysis, DNA ,biology.organism_classification ,Virology ,Molecular biology ,Gene expression profiling ,Autographa californica ,medicine.anatomical_structure ,Gene Expression Regulation ,Cell culture ,Larva ,Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ,Insect Science ,Insect Proteins ,Helicoverpa zea - Abstract
We identified host proteins that changed in response to host cell susceptibility to baculovirus infection. We used three baculovirus–host cell systems utilizing two cell lines derived from pupal ovaries, Hz-AM1 (from Helicoverpa zea) and Hv-AM1 (from Heliothis virescens). Hv-AM1 cells are permissive to Autographa californica multiple nucleopolyhedrovirus (AcMNPV) and semi-permissive to H. zea single nucleopolyhedrovirus (HzSNPV). Hz-AM1 cells are non-permissive to AcMNPV. We challenged each cell line with baculovirus infection and after 24 h determined protein identities by MALDI TOF/TOF mass spectrometry. For Hv-AM1 cells, 21 proteins were identified, and for Hz-AM1 cells, 19 proteins were newly identified (with 8 others having been previously identified). In the permissive relationship, 18 of the proteins changed in expression by 70% or more in AcMNPV infected Hv-AM1 cells as compared with non-infected controls; 12 were significantly decreased and 6 cellular proteins were significantly increased. We also identified 3 virus-specific proteins. In the semi-permissive infections, eight proteins decreased by 2-fold or more. Non-permissive interactions did not lead to substantial changes in host cell protein expression. We hypothesize that some of these proteins act in determining host cell specificity for baculoviruses.
- Published
- 2010
25. The environmental dependence of the stellar-mass-size relation in STAGES galaxies
- Author
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Daniel H. McIntosh, Eelco van Kampen, Meghan E. Gray, Alfonso Aragón-Salamanca, Chien Y. Peng, Knud Jahnke, Christian Wolf, Marco Barden, B. Haeussler, David T. Maltby, and Asmus Boehm
- Subjects
Physics ,Effective radius ,education.field_of_study ,Spiral galaxy ,Stellar mass ,010308 nuclear & particles physics ,Population ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Galaxy ,Spitzer Space Telescope ,Space and Planetary Science ,0103 physical sciences ,Cluster (physics) ,Galaxy formation and evolution ,Astrophysics::Earth and Planetary Astrophysics ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
We present the stellar mass-size relations for elliptical, lenticular, and spiral galaxies in the field and cluster environments using HST/ACS imaging and data from the Space Telescope A901/2 Galaxy Evolution Survey (STAGES). We use a large sample of ~1200 field and cluster galaxies, and a sub-sample of cluster core galaxies, and quantify the significance of any putative environmental dependence on the stellar mass-size relation. For elliptical, lenticular, and high-mass (log M*/M_sun > 10) spiral galaxies we find no evidence to suggest any such environmental dependence, implying that internal drivers are governing their size evolution. For intermediate/low-mass spirals (log M*/M_sun < 10) we find evidence, significant at the 2-sigma level, for a possible environmental dependence on galaxy sizes: the mean effective radius a_e for lower-mass spirals is ~15-20 per cent larger in the field than in the cluster. This is due to a population of low-mass large-a_e field spirals that are largely absent from the cluster environments. These large-a_e field spirals contain extended stellar discs not present in their cluster counterparts. This suggests the fragile extended stellar discs of these spiral galaxies may not survive the environmental conditions in the cluster. Our results suggest that internal physical processes are the main drivers governing the size evolution of galaxies, with the environment possibly playing a role affecting only the discs of intermediate/low-mass spirals.
- Published
- 2009
26. Relating basic properties of bright early-type dwarf galaxies to their location in Abell 901/902
- Author
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F. D. Barazza, C. Wolf, M. E. Gray, S. Jogee, M. Balogh, D. H. McIntosh, D. Bacon, M. Barden, E. F. Bell, A. Böhm, J. A. R. Caldwell, B. Häussler, A. Heiderman, C. Heymans, K. Jahnke, E. van Kampen, K. Lane, I. Marinova, K. Meisenheimer, C. Y. Peng, S. F. Sanchez, A. Taylor, L. Wisotzki, and X. Zheng
- Subjects
Digital Sky Survey ,Stellar Populations ,Cosmology and Gravitation ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Star-Formation Histories ,Population ,Color-Magnitude Relation ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Elliptic Galaxies ,01 natural sciences ,Luminosity ,Spheroidal Galaxies ,0103 physical sciences ,galaxies: formation ,Astrophysics::Solar and Stellar Astrophysics ,Space-Telescope ,Surface brightness ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Dwarf galaxy ,Physics ,education.field_of_study ,Spiral Galaxies ,010308 nuclear & particles physics ,Coma Cluster ,Astronomy and Astrophysics ,galaxies: dwarf ,Galaxy ,Ram pressure ,Space and Planetary Science ,galaxies: clusters: individual: Abell 901/902 ,Magnitude (astronomy) ,Virgo-Cluster Survey ,Elliptical galaxy ,galaxies: structure ,Astrophysics::Earth and Planetary Astrophysics ,galaxies: evolution ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present a study of the population of bright early-type dwarf galaxies in the multiple-cluster system Abell 901/902. We use data from the STAGES survey and COMBO-17 to investigate the relation between the color and structural properties of the dwarfs and their location in the cluster. The definition of the dwarf sample is based on the central surface brightness and includes galaxies in the luminosity range -16 >= M_B >~-19 mag. Using a fit to the color magnitude relation of the dwarfs, our sample is divided into a red and blue subsample. We find a color-density relation in the projected radial distribution of the dwarf sample: at the same luminosity dwarfs with redder colors are located closer to the cluster centers than their bluer counterparts. Furthermore, the redder dwarfs are on average more compact and rounder than the bluer dwarfs. These findings are consistent with theoretical expectations assuming that bright early-type dwarfs are the remnants of transformed late-type disk galaxies involving processes such as ram pressure stripping and galaxy harassment. This indicates that a considerable fraction of dwarf elliptical galaxies in clusters are the results of transformation processes related to interactions with their host cluster., 12 pages, 8 figures, accepted for publication in A&A, typo corrected in abstract
- Published
- 2009
27. Uptake in cancer screening programmes
- Author
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H McIntosh, Julietta Patnick, David Weller, and Allen J. Dietrich
- Subjects
Marketing of Health Services ,Informed choice ,education.field_of_study ,business.industry ,Reminder Systems ,Environmental resource management ,Population ,MEDLINE ,Patient Acceptance of Health Care ,Health services ,Harm ,Patient Education as Topic ,Oncology ,Nursing ,Neoplasms ,Cancer screening ,Humans ,Mass Screening ,Medicine ,business ,education ,Minority Groups - Abstract
For cancer screening programmes to bring about reductions in mortality, a substantial proportion of the population must participate. Programmes with low uptake can be ineffective and can promote inequalities in health-service provision. Strategies to promote uptake are multifaceted, reflecting differences in the cancers targeted, invitees, health-service contexts, and the tests themselves. Accordingly, there is no universal approach. Strategies should accommodate the many factors that can influence uptake and should incorporate the need to promote informed choice. Screening has the potential to cause harm, and there is an ethical imperative to seek out strategies that provide balanced information on cancer screening. Further research is needed to assess newer approaches to promoting uptake, such as IT-based programmes, and to identify strategies that are balanced, self-sustaining, and affordable.
- Published
- 2009
28. Predisposing Factors Related to Adolescent Sexuality Among Students in Rural and Urban School-Based Health Centers in Eastern North Carolina
- Author
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Omur Cinar Elci, Justin B. Moore, and Kristin H. McIntosh
- Subjects
Male ,Rural Population ,Adolescent ,Urban Population ,Demographics ,Sexual Behavior ,Ethnic group ,Ambulatory Care Facilities ,Young Adult ,Sexually active ,Risk Factors ,Surveys and Questionnaires ,Environmental health ,North Carolina ,Humans ,Medicine ,Child ,School-based health centers ,Schools ,Unsafe Sex ,business.industry ,Health Policy ,Public Health, Environmental and Occupational Health ,Odds ratio ,Confidence interval ,Adolescent Behavior ,Female ,Health education ,Adolescent sexuality ,business - Abstract
This study examined possible predisposing factors that may contribute to rural adolescents' early sexual behavior. Sexual behaviors, demographics, family structure, history of abuse, sexually active friends, and substance use were analyzed in 410 rural and urban adolescents, aged 10 to 19 years, who were enrolled in a school-based health center in North Carolina between 2005 and 2007. Results indicated that Black students residing in single-parent urban households were more likely to engage in sex earlier than other analyzed ethnic groups (odds ratio [OR] = 5.2; 95% confidence interval [CI] = 1.1-23.6). As age increased, risk of engaging in sex also increased. Rural students reporting history of abuse had a higher risk of engaging in early sexual behaviors than urban students (OR = 2.6; 95% CI = 1.0-6.8) with a similar history. Students residing in a single-or no-parent household had requested more health education services than those residing in a dual-parent household. An inverse association was observed between the amount of parental communication among urban adolescents and engagement in risky sexual behaviors (OR = 0.3; 95% CI = 0.1-0.9). Rural/urban location and student race should be considered as moderators of the relationships between demographic characteristics and sexual behaviors in adolescents enrolled in a school-based health center.
- Published
- 2009
29. THE EVOLUTION OF THE SCATTER OF THE COSMIC AVERAGE COLOR-MAGNITUDE RELATION: DEMONSTRATING CONSISTENCY WITH THE ONGOING FORMATION OF ELLIPTICAL GALAXIES
- Author
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Daniel H. McIntosh, Christine Ruhland, Boris Häußler, Marco Barden, Eric F. Bell, and Edward N. Taylor
- Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,010504 meteorology & atmospheric sciences ,Population ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,0103 physical sciences ,Galaxy formation and evolution ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Luminosity function (astronomy) ,Physics ,education.field_of_study ,Star formation ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Redshift ,Galaxy ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Chandra Deep Field South ,Elliptical galaxy ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present first measurements of the evolution of the scatter of the cosmic average early-type galaxy color-magnitude relation (CMR) from z=1 to the present day, finding that it is consistent with models in which galaxies are constantly being added to the red sequence through truncation of star formation in blue cloud galaxies. We used a sample of over 700 red sequence, structurally-selected early-type galaxies (defined to have Sersic index >2.5) with redshifts 0, Comment: 13 pages, 13 figures, ApJ in press
- Published
- 2009
30. The STAGES view of red spirals and dusty red galaxies: mass-dependent quenching of star formation in cluster infall
- Author
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Alfonso Aragón-Salamanca, John A. R. Caldwell, Marco Barden, Andy Taylor, Eric F. Bell, Michael L. Balogh, David Bacon, Klaus Meisenheimer, Casey Papovich, Eelco van Kampen, Kyle Lane, Anna Gallazzi, Meghan E. Gray, Daniel H. McIntosh, Catherine Heymans, Asmus Boehm, Xianzhong Zheng, Lutz Wisotzki, Christian Wolf, Chien Y. Peng, B. Haeussler, Fabio D. Barazza, Sebastián F. Sánchez, Shardha Jogee, and Knud Jahnke
- Subjects
Cosmology and Gravitation ,galaxies: spiral ,Digital Sky Survey ,Stellar mass ,Population ,Color-Magnitude Relation ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Low-Redshift Clusters ,01 natural sciences ,infrared: galaxies ,Large-Scale Structure ,surveys ,Morphology-Density Relation ,0103 physical sciences ,Cluster (physics) ,Astrophysics::Solar and Stellar Astrophysics ,education ,Evolution Survey Cosmos ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Physics ,education.field_of_study ,stars: formation ,010308 nuclear & particles physics ,Star formation ,Astrophysics (astro-ph) ,Sigma ,Active Galactic Nuclei ,Astronomy and Astrophysics ,Luminosity Function ,Redshift ,Galaxy ,Virgo Cluster ,Stars ,galaxies: clusters: general ,Environmental Dependence ,Space and Planetary Science ,galaxies: evolution - Abstract
We investigate the properties of optically passive spirals and dusty red galaxies in the A901/2 cluster complex at redshift ~0.17 using restframe near-UV-optical SEDs, 24 micron IR data and HST morphologies from the STAGES dataset. The cluster sample is based on COMBO-17 redshifts with an rms precision of sigma_cz~2000 km/sec. We find that 'dusty red galaxies' and 'optically passive spirals' in A901/2 are largely the same phenomenon, and that they form stars at a substantial rate, which is only 4x lower than that in blue spirals at fixed mass. This star formation is more obscured than in blue galaxies and its optical signatures are weak. They appear predominantly in the stellar mass range of log M*/Msol=[10,11] where they constitute over half of the star-forming galaxies in the cluster; they are thus a vital ingredient for understanding the overall picture of star formation quenching in clusters. We find that the mean specific SFR of star-forming galaxies in the cluster is clearly lower than in the field, in contrast to the specific SFR properties of blue galaxies alone, which appear similar in cluster and field. Such a rich red spiral population is best explained if quenching is a slow process and morphological transformation is delayed even more. At log M*/Msol, Accepted for publication in MNRAS
- Published
- 2009
31. Establishment of a monarch butterfly (Danaus plexippus, Lepidoptera: Danaidae) cell line and its susceptibility to insect viruses
- Author
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Arthur H. McIntosh and James J. Grasela
- Subjects
Baculoviridae ,animal structures ,fungi ,Biology ,biology.organism_classification ,Virology ,Virus ,Lepidoptera genitalia ,Danaus ,Monarch butterfly ,Cell culture ,Insect Science ,Botany ,Trichoplusia ,Fetal bovine serum - Abstract
A cell line from the monarch butterfly Danaus plexippus designated BCIRL-DP-AM/JG was established from adult ovaries. The cell line consisted mainly of round cells and took a prolonged period of time in the growth medium ExCell 401 containing 10% fetal bovine serum and antibiotics before it could be subcultured on a regular basis. The cell line had a population doubling time of 32 h and was susceptible to four baculoviruses (MNPV) but was refractile to a fifth baculovirus, a single nucleopolyhedrovirus (HzSNPV). PxMNPV was the most infectious of the MNPV for BCIRL-DP-AM/JG cell line of D. plexippus producing a titer of 5.9×107 TCID50/ml. The non-occluded Hz-1 virus was also infectious for the D. plexippus cell line. The occlusion bodies produced by the BCIRL-DP-AM/JG cell line were infectious for 24 h old Trichoplusia ni larvae and gave LC50 values equivalent to or better than the LC50 for OB produced in the other susceptible cell lines by the MNPV under study. The identity of the monarch butterfly cell line was established by DAF-PCR.
- Published
- 2009
32. Correlations of the IR Luminosity and Eddington Ratio with a Hard X-Ray-Selected Sample of Active Galactic Nuclei
- Author
-
J. Tueller, R. F. Mushotzky, Lisa M. Winter, and Daniel H. McIntosh
- Subjects
Physics ,Active galactic nucleus ,Astrophysics::High Energy Astrophysical Phenomena ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Redshift ,Luminosity ,law.invention ,Telescope ,Photometry (optics) ,Wavelength ,Space and Planetary Science ,law ,K band ,Astrophysics::Solar and Stellar Astrophysics ,Continuum (set theory) ,Astrophysics::Galaxy Astrophysics - Abstract
We use the SWIFT Burst Alert Telescope (BAT) sample of hard x-ray selected active galactic nuclei (AGN) with a median redshift of 0.03 and the 2MASS J and K band photometry to examine the correlation of hard x-ray emission to Eddington ratio as well as the relationship of the J and K band nuclear luminosity to the hard x-ray luminosity. The BAT sample is almost unbiased by the effects of obscuration and thus offers the first large unbiased sample for the examination of correlations between different wavelength bands. We find that the near-IR nuclear J and K band luminosity is related to the BAT (14 - 195 keV) luminosity over a factor of $10^3$ in luminosity ($L_{IR} \approx L_{BAT}^{1.25}$)and thus is unlikely to be due to dust. We also find that the Eddington ratio is proportional to the x-ray luminosity. This new result should be a strong constraint on models of the formation of the broad band continuum.
- Published
- 2008
33. Bermuda
- Author
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H. M. Komansky, H. McIntosh, and D. Kessaram
- Published
- 2008
34. Influence of selenised dairy proteins on biomarkers of colon cancer risk
- Author
-
Graeme H. McIntosh
- Subjects
Programmed cell death ,Pathology ,medicine.medical_specialty ,Nutrition and Dietetics ,Selenocysteine ,Colorectal cancer ,Azoxymethane ,Public Health, Environmental and Occupational Health ,Medicine (miscellaneous) ,chemistry.chemical_element ,Pharmacology ,Biology ,medicine.disease ,medicine.disease_cause ,Bioavailability ,chemistry.chemical_compound ,chemistry ,Apoptosis ,medicine ,Carcinogenesis ,Selenium - Abstract
Selenium is an essential trace element for mammals, and a component of at least 25 selenoproteins which incorporate the amino acid selenocysteine (Sec). These proteins include a number with oxidoreductase functions. An examination of the selenoproteins and their influence on carcinogenesis in an animal model may assist in determining their relevance in chemoprevention. Food sources offer a number of organic forms of selenium, with selenomethionine a common component, as in selenised yeasts. A selenium-rich dairy protein product has been developed (TaturaBioSe, Tatura Milk Industries, Tatura, Victoria) which could improve selenium status in populations considered marginal or deficient. It could also provide higher intakes (e.g. several fold above recommended dietary intake recommendations) of potential benefit as chemopreventive to those at greater risk of some selenium-responsive diseases, such as some sporadic colorectal cancers. Clinical studies are showing it to be a safe, palatable product for consumption in the form provided. Dairy protein selenium at 1 ppm in diet had a significant chemopreventive effect compared with control (0.05 ppm Se) in an azoxymethane model of colon cancer. Colon tumour incidence in rats was down by 29%, and tumour burden (colon tumours/rat) was halved, effects not observed when an equivalent Se concentration was provided as yeast selenium. When assessed by plasma Se concentration, this dairy protein form of selenium showed greater bioavailability (as assessed by plasma selenium) as well as efficacy in chemoprevention. Programmed cell death (apoptosis) was increased in colonic crypts and crypt height significantly diminished. The influence on early changes in carcinogenesis provides an insight into possible mechanism(s) of action. Histological and biochemical assays (e.g. monitoring oxidoreductase enzymes) could potentially provide early biomarkers with clinical relevance.
- Published
- 2008
35. Bioavailability of selenium from selenium-enriched milk assessed in the artificially reared neonatal pig
- Author
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P. T. Doyle, G. P. Walker, Graeme P. Young, C. Richard Stockdale, Frank R. Dunshea, Graeme H. McIntosh, J. W. Heard, C. M. Leddin, and Raffaele Uglietta
- Subjects
chemistry.chemical_classification ,Nutrition and Dietetics ,Glutathione peroxidase ,Selenoprotein P ,Fortification ,food and beverages ,chemistry.chemical_element ,Selenate ,Bioavailability ,Whole milk ,chemistry.chemical_compound ,Animal science ,chemistry ,Dry matter ,Selenium - Abstract
There is interest in pre-farm gate fortification of the diet with highly bioavailable selenium (Se) to improve public health, so the aim of the present study was to determine the bioavailabilities of Se from Se-enriched whole milk and milk replacers supplemented with exogenous Se in neonatal pigs. Milk enriched with Se (1070 mg Se/kg dry matter (DM); HSeM) was obtained from cows supplemented with selenised yeast while the control milk diet (135 mg Se/kg DM; LSeM) was made using milk powder from non-supplemented cows. Additional diets were formulated by adding selenised yeast (HSP) or selenate (HSN) to the LSeM diet to give final Se concentrations of 1070 mg Se/kg DM. Neonatal pigs were trained to drink milk and then randomly allocated to their four respective diets and slaughter times (0, 7, 14, 28 and 42 days of feeding). Plasma Se increased over the first 21 days in pigs consuming HSeM, reaching a value over three times higher than the LSeM pigs. Plasma Se concentrations plateaued at 45, 125, 122 and 170 mg/mL for LSeM, HSN, HSP and HSeM pigs, respectively (P < 0.001). After 28 days, muscle Se plateaued at 47, 106, 237 and 486 mg/kg for LSeM, HSN, HSP and HSeM pigs, respectively (P < 0.001). Colonic selenoprotein P gene expression was greater (P = 0.024) in pigs fed HSeM compared with LSeM while the HSP and HSN were intermediate. These data suggest that Se in milk from cows fed selenised yeast is highly bioavailable and may offer a means of delivering supplemental Se to humans.
- Published
- 2008
36. Pulse oximetry index: a simple arterial assessment for patients with venous disease
- Author
-
M. Zamiri, W. S. Douglas, H. Mcintosh, M. Loney, J. Bianchi, and Robert S. Dawe
- Subjects
Adult ,Male ,Nursing (miscellaneous) ,Brachial Artery ,Arterial Occlusive Diseases ,Severity of Illness Index ,Venous leg ulcer ,Varicose Ulcer ,medicine.artery ,medicine ,Humans ,Mass Screening ,In patient ,Oximetry ,Prospective Studies ,Brachial artery ,Prospective cohort study ,Nursing Assessment ,Aged ,Aged, 80 and over ,Peripheral Vascular Diseases ,Ultrasonography, Doppler, Duplex ,medicine.diagnostic_test ,business.industry ,Contraindications ,Patient Selection ,Middle Aged ,Skin Care ,medicine.disease ,body regions ,Pulse oximetry ,Leg ulcer ,Nursing Evaluation Research ,Scotland ,Anesthesia ,Linear Models ,Female ,Fundamentals and skills ,Venous disease ,business ,Stockings, Compression ,Ankle–brachial pressure index - Abstract
Objective: To provide additional safety data comparing ankle brachial pressure index (ABPI) and pulse oximetry (Lanarkshire Oximetry Index, LOI) as measures of arterial circulation in patients with venous disease of the leg. Method: A total of 107 (195 legs) attending hospital leg ulcer clinics participated in this prospective open study. We attempted to measure brachial and foot arterial pressures in all patients using both the handheld Doppler method (ABPI) and pulse oximeter method (LOI). Features of patients with limbs in which either the ABPI or LOI could not be assessed were documented. ABPI and LOI values were compared, and agreement between the two assessment methods was assessed. Results: We found the LOI measurement to be a simpler technique than Doppler ABPI measurement, with an endpoint less prone to the subjective variability associated with the Doppler method. Of the 195 legs assessed, we obtained LOI in 10 in which an ABPI could not be recorded. LOI could not be recorded in only one leg. There was a linear association (pConclusion: Pulse oximetry LOI is a simple alternative to Doppler ABPI in the screening of patients for arterial disease that could be a contraindication to, or require modification of, compression therapy. It can be measured in some legs that cannot be assessed by Doppler ultrasound. Declaration of interest: None.
- Published
- 2008
37. Poor reporting and inadequate searches were apparent in systematic reviews of adverse effects
- Author
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Yoon K. Loke, Su Golder, and H McIntosh
- Subjects
medicine.medical_specialty ,Evidence-based practice ,Drug-Related Side Effects and Adverse Reactions ,Epidemiology ,business.industry ,Clinical effectiveness ,Alternative medicine ,Information Storage and Retrieval ,Evidence-based medicine ,Databases, Bibliographic ,Review Literature as Topic ,Systematic review ,Meta-Analysis as Topic ,Vocabulary, Controlled ,Meta-analysis ,Outcome Assessment, Health Care ,medicine ,Meta analisis ,Humans ,Intensive care medicine ,Adverse effect ,business - Abstract
Objective Systematic reviews incorporating adverse effects are assuming increasing importance as questions raised extend beyond clinical effectiveness to all effects (beneficial and harmful). The aim of this study was to survey the methods used to identify relevant studies for systematic reviews of adverse effects. Study Design and Setting All records within the Database of Abstracts of Reviews of Effects and the Cochrane Database of Systematic Reviews were scanned for systematic reviews in which the primary outcomes were adverse effects. Two information professionals independently assessed the methods used to identify relevant research as reported in the 277 reviews that met the inclusion criteria. Results A major weakness of the reviews was inadequate reporting of the search strategies used. In addition, of the reviews that did report a search strategy, few used the sensitive search strategies recommended for systematic reviews. The majority of reviews did not search more than one or two databases, and few other methods of identifying information were used. Conclusion This investigation shows the variation in the searching element of systematic reviews of adverse effects and demonstrates that the reporting of the methods used to identify research in such reviews could be vastly improved.
- Published
- 2008
38. Clinical information sources used by hospital doctors in Mongolia
- Author
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Jean H. McIntosh, Joanne Callen, and Battogtokh Buyankhishig
- Subjects
Adult ,Male ,Health Knowledge, Attitudes, Practice ,Decision Making ,education ,MEDLINE ,Developing country ,Health Informatics ,Special needs ,Access to Information ,Nursing ,Physicians ,Surveys and Questionnaires ,Computer literacy ,Humans ,Medicine ,Health policy ,Response rate (survey) ,Medical education ,Attitude to Computers ,business.industry ,Information technology ,Mongolia ,Middle Aged ,Cross-Sectional Studies ,Information source ,Female ,business ,Medical Informatics - Abstract
Background Information technology presents new opportunities to facilitate clinicians’ access to up-to-date clinical information. Developing countries have special needs in this area and the problems encountered in obtaining clinical information have not been well researched, particularly for hospital doctors. No previous study has examined which clinical information sources Mongolian hospital doctors’ use and the problems they may encounter in obtaining information. This study addressed an important knowledge gap by examining clinical information-seeking practices of Mongolian hospital doctors. The objectives of the study were to ascertain: (a) which clinical information sources were used in clinical decision-making; (b) the level of confidence in these information sources, and (c) the impact these information sources had on clinical decision-making. Also investigated was proficiency in English language and computer skills, as these factors could influence ability to obtain clinical information electronically. Methods Self-administered questionnaires were given to 263 doctors from the two largest hospitals in Ulaanbaatar, the capital city of Mongolia. Respondents answered questions about 10 information sources: colleagues; local and foreign textbooks; local and foreign journals; personal notes; computer-aided literature searches; Mongolian clinical practice guidelines; and brief updates and health policies developed in Mongolia. Parameters of interest included: frequency of use; confidence in the sources; and perceived impact of the sources on clinical decision-making. Results The response rate was 87% (229). The respondents indicated that discussion with colleagues was the most frequently used information source, foreign medical textbooks most commonly inspired high confidence, and discussion with colleagues was the source most often perceived as having a high impact on clinical decision-making. For all sources, high confidence and high impact were strongly associated with each other. Only 26% of respondents understood English well, and only 41% had excellent/good computer skills. English language and computer skills were strongly associated with undertaking computer-aided literature searches and with age. Female respondents were less likely than males to have excellent/good computer skills and less likely to undertake computer-aided literature searches. Conclusions Satisfying the clinical information needs of doctors in less developed countries is particularly challenging and even though improvements in information technology can facilitate access to knowledge, there still exist barriers. Health policies which promote computer skills and English language among doctors may contribute substantially to best medical practice in Mongolia.
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- 2008
39. Prostaglandins A1 and E1 influence gene expression in an established insect cell line (BCIRL-HzAM1 cells)
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David Stanley, Cynthia L. Goodman, Qisheng Song, Arthur H. McIntosh, and Shiheng An
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Time Factors ,In silico ,Moths ,Antiviral Agents ,Biochemistry ,Cell Line ,Fibrinolytic Agents ,Gene expression ,Animals ,Alprostadil ,Molecular Biology ,Ion transporter ,Prostaglandins A ,Ion Transport ,Two-dimensional gel electrophoresis ,biology ,Ovary ,fungi ,Pupa ,Lipid metabolism ,Metabolism ,Lipid Metabolism ,biology.organism_classification ,Gene Expression Regulation ,Insect Science ,Insect Proteins ,Female ,Helicoverpa zea ,Signal transduction ,Signal Transduction - Abstract
Prostaglandins (PGs) and other eicosanoids exert important physiological actions in insects and other invertebrates, including influencing ion transport and mediating cellular immune defense functions. Although these actions are very well documented, we have no information on the mechanisms of PGs actions in insect cells. Here we report on the outcomes of experiments designed to test our hypothesis that PGs modulate gene expression in an insect cell line established from pupal ovarian tissue of the moth Helicoverpa zea (BCIRL-HzAM1 cells). We treated cells with either PGA(1) or PGE(1) for 12 or 24h then analyzed cell lysates by 2-D electrophoresis. Analysis of the gels by densitometry revealed substantial changes in protein expression in some of the protein spots we analyzed. These spots were processed for mass spectrometric analysis by MALDI TOF/TOF, which yielded in silico protein identities for all 34 spots. The apparent changes in three of the proteins were confirmed by semi-quantative PCR, showing that the changes in mRNA expression were reflected in changes in protein expression. The 34 proteins were sorted into six categories, protein actions, lipid metabolism, signal transduction, protection, cell functions and metabolism. The findings support the hypothesis that one mechanism of PG action in insect cells is the modulation of gene expression.
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- 2008
40. Scaling Relations of Spiral Galaxies
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Avishai Dekel, Daniel A. Dale, Aaron A. Dutton, Daniel H. McIntosh, Stéphane Courteau, Lauren A. MacArthur, and F. C. van den Bosch
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Physics ,Spiral galaxy ,Stellar population ,010308 nuclear & particles physics ,Astrophysics (astro-ph) ,Dark matter ,FOS: Physical sciences ,Sigma ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Galaxy ,Luminosity ,Dark matter halo ,Space and Planetary Science ,0103 physical sciences ,Surface brightness ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
We construct a large data set of global structural parameters for 1300 field and cluster spiral galaxies and explore the joint distribution of luminosity L, optical rotation velocity V, and disk size R at I- and 2MASS K-bands. The I- and K-band velocity-luminosity (VL) relations have log-slopes of 0.29 and 0.27, respectively with sigma_ln(VL)~0.13, and show a small dependence on color and morphological type in the sense that redder, early-type disk galaxies rotate faster than bluer, later-type disk galaxies for most luminosities. The VL relation at I- and K-bands is independent of surface brightness, size and light concentration. The log-slope of the I- and K-band RL relations is a strong function of morphology and varies from 0.25 to 0.5. The average dispersion sigma_ln(RL) decreases from 0.33 at I-band to 0.29 at K, likely due to the 2MASS selection bias against lower surface brightness galaxies. Measurement uncertainties are sigma_ln(V)~0.09, sigma_ln(L)~0.14 and somewhat larger and harder to estimate for ln(R). The color dependence of the VL relation is consistent with expectations from stellar population synthesis models. The VL and RL residuals are largely uncorrelated with each other; the RV-RL residuals show only a weak positive correlation. These correlations suggest that scatter in luminosity is not a significant source of the scatter in the VL and RL relations. The observed scaling relations can be understood in the context of a model of disk galaxies embedded in dark matter halos that invokes low mean spin parameters and dark halo expansion, as we describe in our companion paper (Dutton et al. 2007). We discuss in two appendices various pitfalls of standard analytical derivations of galaxy scaling relations, including the Tully-Fisher relation with different slopes. (Abridged)., Comment: Accepted for publication at ApJ. The full document, with high-resolution B&W and colour figures, is available at http://www.astro.queensu.ca/~courteau/papers/VRL2007ApJ.pdf . Our data base for 1303 spiral galaxies is also available at http://www.astro.queensu.ca/~courteau/data/VRL2007.dat
- Published
- 2007
41. A Toolbox for Quantitative Gene Expression in Varroa destructor: RNA Degradation in Field Samples and Systematic Analysis of Reference Gene Stability
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Ewan M. Campbell, Alan S. Bowman, and Catriona H. Mcintosh
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0106 biological sciences ,0301 basic medicine ,RNA Stability ,lcsh:Medicine ,Gene Expression ,01 natural sciences ,Biochemistry ,Contractile Proteins ,Genes, Reporter ,Specimen Storage ,Deformed wing virus ,Reference genes ,Gene expression ,lcsh:Science ,2. Zero hunger ,Genetics ,Mites ,Multidisciplinary ,biology ,NADH dehydrogenase ,Bees ,Complementary DNA ,Insects ,Nucleic acids ,Varroa ,Sample collection ,Honey Bees ,Research Article ,Arthropoda ,Forms of DNA ,Varroidae ,Real-Time Polymerase Chain Reaction ,03 medical and health sciences ,Extraction techniques ,Animals ,business.industry ,Gene Expression Profiling ,lcsh:R ,Organisms ,Reproducibility of Results ,Biology and Life Sciences ,Proteins ,DNA ,biology.organism_classification ,Invertebrates ,Hymenoptera ,RNA extraction ,Actins ,Biotechnology ,Gene expression profiling ,Research and analysis methods ,010602 entomology ,Cytoskeletal Proteins ,030104 developmental biology ,Varroa destructor ,Storage and Handling ,biology.protein ,lcsh:Q ,business ,Transcriptome - Abstract
Varroa destructor is the major pest of Apis mellifera and contributes to the global honey bee health crisis threatening food security. Developing new control strategies to combat Varroa will require the application of molecular biology, including gene expression studies by quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR). Both high quality RNA samples and suitable stable internal reference genes are required for accurate gene expression studies. In this study, ten candidate genes (succinate dehydrogenase (SDHA), NADH dehydrogenase (NADH), large ribsosmal subunit, TATA-binding protein, glyceraldehyde-3-phosphate dehydrogenase, 18S rRNA (18S), heat-shock protein 90 (HSP90), cyclophilin, α-tubulin, actin), were evaluated for their suitability as normalization genes using the geNorm, Normfinder, BestKeeper, and comparative ΔCq algorithims. Our study proposes the use of no more than two of the four most stable reference genes (NADH, 18S, SDHA and HSP90) in Varroa gene expression studies. These four genes remain stable in phoretic and reproductive stage Varroa and are unaffected by Deformed wing virus load. When used for determining changes in vitellogenin gene expression, the signal-to-noise ratio (SNR) for the relatively unstable genes actin and α-tubulin was much lower than for the stable gene combinations (NADH + HSP90 +18S; NADH + HSP90; or NADH). Using both electropherograms and RT-qPCR for short and long amplicons as quality controls, we demonstrate that high quality RNA can be recovered from Varroa up to 10 days later stored at ambient temperature if collected into RNAlater and provided the body is pierced. This protocol allows the exchange of Varroa samples between international collaborators and field sample collectors without requiring frozen collection or shipping. Our results make important contributions to gene expression studies in Varroa by proposing a validated sampling protocol to obtain high quality Varroa RNA and the validation of suitable reference genes for expression studies in this globally important pest.
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- 2015
42. Testing the Modern Merger Hypothesis via the Assembly of Massive Blue Elliptical Galaxies in the Local Universe
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Gregory Rudnick, C. Tremonti, Tim Haines, Daniel H. McIntosh, and Sebastián F. Sánchez
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Physics ,Luminous infrared galaxy ,Star formation ,Astronomy ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Galaxy merger ,Disc galaxy ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Peculiar galaxy ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Elliptical galaxy ,Lenticular galaxy ,Astrophysics::Galaxy Astrophysics - Abstract
The modern merger hypothesis offers a method of forming a new elliptical galaxy through merging two equal-mass, gas-rich disk galaxies fuelling a nuclear starburst followed by efficient quenching and dynamical stabilization. A key prediction of this scenario is a central concentration of young stars during the brief phase of morphological transformation from highly-disturbed remnant to new elliptical galaxy. To test this aspect of the merger hypothesis, we use integral field spectroscopy to track the stellar Balmer absorption and 4000\AA\ break strength indices as a function of galactic radius for 12 massive (${\rm M_{*}}\ge10^{10}{\rm M_{\odot}}$), nearby (${\rm z}\le0.03$), visually-selected plausible new ellipticals with blue-cloud optical colours and varying degrees of morphological peculiarities. We find that these index values and their radial dependence correlate with specific morphological features such that the most disturbed galaxies have the smallest 4000\AA\ break strengths and the largest Balmer absorption values. Overall, two-thirds of our sample are inconsistent with the predictions of the modern merger hypothesis. Of these eight, half exhibit signatures consistent with recent minor merger interactions. The other half have star formation histories similar to local, quiescent early-type galaxies. Of the remaining four galaxies, three have the strong morphological disturbances and star-forming optical colours consistent with being remnants of recent, gas-rich major mergers, but exhibit a weak, central burst consistent with forming $\sim5\%$ of their stars. The final galaxy possesses spectroscopic signatures of a strong, centrally-concentrated starburst and quiescent core optical colours indicative of recent quenching (i.e., a post-starburst signature) as prescribed by the modern merger hypothesis., Comment: 25 pages, 37 figures, accepted to MNRAS
- Published
- 2015
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43. A catalog of visual-like morphologies in the 5 CANDELS fields using deep-learning
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Dale D. Kocevski, Mariangela Bernardi, Guillermo Barro, Romaric Gravet, Daniel H. McIntosh, Marc Huertas-Company, Sandra M. Faber, David C. Koo, P. Dimauro, Pablo G. Pérez-González, Francesco Shankar, Simona Mei, Eric F. Bell, Jeyhan S. Kartaltepe, G. Cabrera-Vives, Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), AUTRES, Institut de recherches sur la catalyse et l'environnement de Lyon (IRCELYON), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Institut d'astrophysique spatiale (IAS), and Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Astrofísica ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Point source ,FOS: Physical sciences ,Classification scheme ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Surveys ,Image (mathematics) ,Galaxies: structure ,Fraction (mathematics) ,Limit (mathematics) ,Zero bias ,Astrophysics::Galaxy Astrophysics ,Physics ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,business.industry ,Deep learning ,Galaxies: high-redshift ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Astronomía ,Space and Planetary Science ,[SDU]Sciences of the Universe [physics] ,Astrophysics of Galaxies (astro-ph.GA) ,Artificial intelligence ,Catalogs ,business ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present a catalog of visual like H-band morphologies of $\sim50.000$ galaxies ($H_{f160w}\sim1.25$. The algorithm is trained on GOODS-S for which visual classifications are publicly available and then applied to the other 4 fields. Following the CANDELS main morphology classification scheme, our model retrieves the probabilities for each galaxy of having a spheroid, a disk, presenting an irregularity, being compact or point source and being unclassifiable. ConvNets are able to predict the fractions of votes given a galaxy image with zero bias and $\sim10\%$ scatter. The fraction of miss-classifications is less than $1\%$. Our classification scheme represents a major improvement with respect to CAS (Concentration-Asymmetry-Smoothness)-based methods, which hit a $20-30\%$ contamination limit at high z. The catalog is released with the present paper via the $\href{http://rainbowx.fis.ucm.es/Rainbow_navigator_public}{Rainbow\,database}$, Comment: Accepted for publication in ApjS. Figure 10 summarizes the excellent agreement between our classification and a pure visual one. Table 3 shows the content of the catalogs. The catalogs are available from the Rainbow database (http://rainbowx.fis.ucm.es/Rainbow_navigator_public) based on the selections from the CANDELS team and cross-matched with 3D-HST v4.1 catalogs
- Published
- 2015
- Full Text
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44. Anticancer properties of panduratin A isolated from Boesenbergia pandurata (Zingiberaceae)
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Graham P. Jones, Chandra Kirana, Graeme H. McIntosh, and Ian R. Record
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Kaempferia ,food.ingredient ,biology ,Traditional medicine ,business.industry ,Azoxymethane ,biology.organism_classification ,Bioactive compound ,Boesenbergia ,chemistry.chemical_compound ,food ,chemistry ,Molecular Medicine ,Medicine ,Zingiberaceae ,Curcuma ,business ,Boesenbergia rotunda ,Aberrant crypt foci - Abstract
Extract of Boesenbergia pandurata (Kaempferia pandurata) (Zingiberaceae) has been used as a replacement for K. rotunda, the main ingredient of a popular traditional tonic called “jamu” especially for women in Indonesia. From our previous study, ethanolic extract of B. pandurata showed strong inhibitory effects on the growth of cancer cells, similar to ethanolic extract of Curcuma longa. C. longa and its bioactive compound, curcumin, have shown potential anticancer activity in in vitro and in vivo studies and have undergone clinical trials. Panduratin A, a chalcone derivative isolated from B. pandurata, was found to inhibit the growth of MCF-7 human breast cancer and HT-29 human colon adenocarcinoma cells with an IC50 of 3.75 and 6.56 µg/ml, respectively. Panduratin A arrested cancer cells labelled with Annexin-V and propidium iodide in the G0/G1 phase and induced apoptosis in a dose-dependent manner. In an animal model study, male Sprague–Dawley rats were fed with AIN diet containing ethanolic extracts prepared from the equivalent of 4% by weight of dried rhizomes of B. pandurata and C. longa. Aberrant crypt foci (ACFs) were induced by two subcutaneous doses (15 mg/kg body weight) of azoxymethane (AOM) 1 week apart. The rats were killed 10 weeks later, and the ACFs were assessed in the colon. At the dose given to rats, it appeared that the extracts were not toxic. Total ACFs were slightly reduced by B. pandurata extract compared to control group but not significantly different. Extract of B. pandurata may have a protective effect against colon cancer but additional studies using different models, such as a breast cancer model, need to be carried out.
- Published
- 2006
45. Color, Structure, and Star Formation History of Dwarf Galaxies over the Last ∼3 Gyr with GEMS and SDSS
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John A. R. Caldwell, Hans-Walter Rix, Marco Barden, Shardha Jogee, Eric F. Bell, Christian Wolf, Daniel H. McIntosh, Fabio D. Barazza, Klaus Meisenheimer, and Chien Y. Peng
- Subjects
Physics ,Brightness ,Star formation ,Astrophysics (astro-ph) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Advanced Camera for Surveys ,Galaxy ,Redshift ,Space and Planetary Science ,Galaxy formation and evolution ,Astrophysics::Solar and Stellar Astrophysics ,Stellar structure ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Galaxy Astrophysics ,Dwarf galaxy - Abstract
We present a study of the colors, structural properties, and star formation histories for a sample of ~1600 dwarfs over look-back times of ~3 Gyr (z=0.002-0.25). The sample consists of 401 distant dwarfs drawn from the Galaxy Evolution from Morphologies and SEDs (GEMS) survey, which provides high resolution Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) images and accurate redshifts, and of 1291 dwarfs at 10-90 Mpc compiled from the Sloan Digitized Sky Survey (SDSS). The sample is complete down to an effective surface brightness of 22 mag arcsec^-2 in z and includes dwarfs with M_g=-18.5 to -14 mag. Rest-frame luminosities in Johnson UBV and SDSS ugr filters are provided by the COMBO-17 survey and structural parameters have been determined by S\'ersic fits. We find that the GEMS dwarfs are bluer than the SDSS dwarfs by ~0.13 mag in g-r, which is consistent with the color evolution over ~2 Gyr of star formation histories involving moderate starbursts and long periods of continuous star formation. The full color range of the samples cannot be reproduced by single starbursts of different masses or long periods of continuous star formation alone. Furthermore, an estimate of the mechanical luminosities needed for the gas in the GEMS dwarfs to be completely removed from the galaxies shows that a significant number of low luminosity dwarfs are susceptible to such a complete gas loss, if they would experience a starburst. On the other hand, a large fraction of more luminous dwarfs is likely to retain their gas. We also estimate the star formation rates per unit area for the GEMS dwarfs and find good agreement with the values for local dwarfs., Comment: 31 pages, 13 figures, accepted for publication in the ApJ
- Published
- 2006
46. The impact of cheese consumption on markers of cardiovascular risk in rats
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Graeme H. McIntosh, Romain Descamps, Peter Roupas, Peter J. Royle, and Ben Scherer
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chemistry.chemical_classification ,Very low-density lipoprotein ,Low protein ,Triglyceride ,Cholesterol ,Fatty acid ,Biology ,Applied Microbiology and Biotechnology ,chemistry.chemical_compound ,chemistry ,Tallow ,Casein ,Arachidonic acid ,Food science ,Food Science - Abstract
We examined the influence of cheddar cheese compared with beef meat/tallow and casein/canola oil diets on biomarkers of cardiovascular health, using male Sprague Dawley laboratory rats. The total omega 3 ( ω 3 ) fatty acid content of cheese was 50% higher than that of tallow, and 20% higher than that of canola oil diets. Diets were designed to simulate a ‘western style’ diet (high fat/low protein/low calcium). Diets were balanced for energy and major nutrients, and contained 17.6% (w/w) fat and 13.7% protein, except for the 50% cheese diet, which had higher total cholesterol and calcium. We observed significantly lower plasma total cholesterol and non-HDL (LDL, IDL VLDL) cholesterol concentrations (−46%) and higher plasma triglyceride concentrations (+50%) in the 50% cheese diet-fed rats than in the beef meat/tallow-fed rats. The amount of triglyceride in rat livers was about 30% higher in the casein+tallow and beef meat+tallow-fed rats than in the other treatments. Fatty acid content of the liver triglycerides showed lower 18:1 and higher ω 3 fatty acids: 18:3 ( α -linolenic), 20:5 (eicosapentaenoic) and 22:6 (docosahexaenoic) in the cheese-fed than the tallow-fed rats, these concentrations being equivalent to that of the canola oil-fed rats. Liver triglyceride arachidonic acid (20:4) concentration was comparable between the cheese and canola oil sources of fat, but lower in the tallow-fed rats. These concentrations could be interpreted as indicating a good balance between the ω 3 and ω 6 long-chain precursors of eicosanoids responsible for significant biological effects, and representing a healthier fatty acid profile in cheese-fed animals than with the other dietary treatment groups. Other markers examined showed no significant deleterious effects associated with cheese consumption. The evidence in this rat study suggests that the fat derived from cheese could offer some significant benefits to health, as shown by the long-chain ω 3 fatty acid composition of liver triglycerides and their known benefits to health.
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- 2006
47. Growth and development of the knapweed root weevil, Cyphocleonus achates, on a meridic larval diet
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Maureen Knop Wright, James J. Grasela, R.M. Wagner, Arthur H. McIntosh, Cynthia L. Goodman, Bradley Vickers, Sarah J. Phipps, Paula Peters, Steve Saathoff, and Henda Nabli
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Cyphocleonus achates ,Larva ,Centaurea maculosa ,biology ,Weevil ,media_common.quotation_subject ,Biological pest control ,Insect ,biology.organism_classification ,Animal science ,Insect Science ,Curculionidae ,Botany ,Weed ,Agronomy and Crop Science ,media_common - Abstract
Cyphocleonus achates , the knapweed weevil, is an effective biological control agent of the invasive weed, Centaurea maculosa Lam. A meridic diet was developed and tested for the rearing of the larval stage of this insect. Using this diet, C. achates was reared for over three generations, with the adults being offered knapweed plants for feeding and oviposition in greenhouse conditions. Slight or no differences were seen between insects reared on a standard meridic diet formulation and one containing knapweed tissues. The following life history parameters were monitored over the three generations: percent egg hatch (ranging from 42.9 to 59.1%), time to egg hatch (20.0–23.2 days), time to adult emergence (52.0–54.1 days), adult weights 3 days post-eclosion (101.9–117.0 mg), percent adult emergence (48.3–58.6%), and percent mortality/deformity in the different stages (with mortality occurring primarily in the early larval stages). Additionally, a study involving low temperature and short day conditions suggested that C. achates could be maintained for longer periods of time in larval diet cells when placed in growth-retarding conditions, although percent adult emergence was lower. External morphology was also studied in order to distinguish between the sexes to ensure that each adult cage had a similar ratio of females to males. Abdominal features were found to be the most dependable characteristics for use when determining the sex of adult C. achates .
- Published
- 2006
48. Weak lensing studies from space with GEMS
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Andy Taylor, Steven V. W. Beckwith, Lutz Wisotzki, Michael L. Brown, Christian Wolf, Sebastián F. Sánchez, Klaus Meisenheimer, Andrea Borch, S. Jogee, Chien Y. Peng, Catherine Heymans, Knud Jahnke, Boris Häußler, Rachel S. Somerville, H. W. Rix, J. A. R. Caldwell, Marco Barden, Eric F. Bell, and Daniel H. McIntosh
- Subjects
Physics ,COSMIC cancer database ,Space and Planetary Science ,Chandra Deep Field South ,Astronomy ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Space (mathematics) ,Advanced Camera for Surveys ,Astrophysics::Galaxy Astrophysics ,Galaxy ,Weak gravitational lensing - Abstract
The Galaxy Evolution from Morphology and SEDs (GEMS) survey is the largest contiguous field ever imaged in colour by HST with the Advanced Camera for Surveys (ACS), spanning some 900 square arcmins in the Chandra deep field south (CDFS). We discuss the power of the ACS for weak lensing studies and present preliminary results from our cosmic shear analysis of GEMS. Selecting a subset of GEMS galaxies which are resolved in deep ground-based R-band imaging of the CDFS from the COMBO-17 survey, we compare the cosmic shear signal determined from the ground and from space. (c) 2005 Published by Elsevier B.V.
- Published
- 2005
49. Patients' Perceptions of General Practitioners Using Computers during the Patient-Doctor Consultation
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Joanne Callen, Meagan Bevis, and Jean H. McIntosh
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,Medical Records Systems, Computerized ,Health records ,Patient satisfaction ,Surveys and Questionnaires ,Computer usage ,Humans ,Medicine ,Physician-Patient Relations ,Adult patients ,Attitude to Computers ,business.industry ,General Medicine ,Middle Aged ,Quarter (United States coin) ,Patient Care Management ,Cross-Sectional Studies ,Patient perceptions ,Patient Satisfaction ,Family medicine ,General practice ,Female ,New South Wales ,Family Practice ,business - Abstract
In this study 85 adult patients attending a Sydney general practice were asked for their views on computer-assisted consultations; 77 (91%) agreed to participate. In general, patients agreed they could still talk easily with their doctor, and felt listened to, while the doctor used the computer (87% & 75% respectively). More than half the patients felt the computer contributed to better treatment, although a quarter believed consultations were prolonged. About half the patients agreed that the doctor did not often explain the role of the computer. Given the national plans for increasing computerisation of health records (Health Connect), this research suggests that more attention should be given to involving patients in e-health developments.
- Published
- 2005
50. Ultraviolet Light from Young Stars in GEMS Quasar Host Galaxies at 1.8 < z < 2.75
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K. Jahnke, S. F. Sanchez, L. Wisotzki, M. Barden, S. V. W. Beckwith, E. F. Bell, A. Borch, J. A. R. Caldwell, B. Haussler, C. Heymans, S. Jogee, D. H. McIntosh, K. Meisenheimer, C. Y. Peng, H.‐W. Rix, R. S. Somerville, and C. Wolf
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Physics ,education.field_of_study ,Population ,Flux ,High resolution ,Astronomy and Astrophysics ,Quasar ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Redshift ,Galaxy ,Stars ,Space and Planetary Science ,education ,Host (network) ,Astrophysics::Galaxy Astrophysics - Abstract
We have performed HST imaging of a sample of 23 high-redshift (1.8
- Published
- 2004
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