1,016 research outputs found
A Multiwavelength View at the Heart of the Superwind in NGC 253
Here we present new optical data from the Hubble Space Telescope of the NGC
253 central region, which reveal numerous discrete sources in a ring--like
structure. This is combined with data at infrared, millimeter, radio and X-ray
wavelengths to examine the nature of these discrete sources and the nucleus
itself. We find that the majority of optical/IR/mm sources are young star
clusters which trace out a ~50 pc ring, that defines the inner edge of a cold
gas torus. This reservoir of cold gas has probably been created by gas inflow
from a larger scale bar and deposited at the inner Lindblad resonance. The
family of compact radio sources lie interior to the starburst ring, and in
general do not have optical or IR counterparts. They are mostly SNRs. The radio
nucleus, which is probably an AGN, lies near the centre of the ring. The X-ray
emission from the nuclear source is extended in the ROSAT HRI detector
indicating that not all of the X-ray emission can be associated with the AGN.
The lack of X-ray variability and the flat radio spectrum of the nucleus,
argues against an ultraluminous SN as the dominant energetic source at the
galaxy core. The diffuse emission associated with the outflowing superwind is
present in the central region on a size scale consistent with the idea of
collimation by the gas torus.Comment: 26 pages, Latex, 6 figures, 4 tables, submitted to MNRA
Absorption coefficients in light oil scrubbers
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1941.Includes bibliographical references (leaf 91).by Edward Colin Forbes, John Yü-Ling Kao.M.S
HCMV-encoded NK modulators: Lessons from in vitro and in vivo genetic variation
Human cytomegalovirus (HCMV) is under constant selective pressure from the immune system in vivo. Study of HCMV genes that have been lost in the absence of, or genetically altered by, such selection can focus research toward findings of in vivo significance. We have been particularly interested in the most pronounced change in the highly passaged laboratory strains AD169 and Towne—the deletion of 13–15 kb of sequence (designated the UL/b′ region) that encodes up to 22 canonical genes, UL133-UL150. At least 5 genes have been identified in UL/b′ that inhibit NK cell function. UL135 suppresses formation of the immunological synapse (IS) by remodeling the actin cytoskeleton, thereby illustrating target cell cooperation in IS formation. UL141 inhibits expression of two activating ligands (CD155, CD112) for the activating receptor CD226 (DNAM-1), and two receptors (TRAIL-R1, R2) for the apoptosis-inducing TRAIL. UL142, ectopically expressed in isolation, and UL148A, target specific MICA allotypes that are ligands for NKG2D. UL148 impairs expression of CD58 (LFA-3), the co-stimulatory cell adhesion molecule for CD2 found on T and NK cells. Outside UL/b′, studies on natural variants have shown UL18 mutants change affinity for their inhibitory ligand LIR-1, while mutations in UL40's HLA-E binding peptide differentially drive NKG2C+ NK expansions. Research into HCMV genomic stability and its effect on NK function has provided important insights into virus:host interactions, but future studies will require consideration of genetic variability and the effect of genes expressed in the context of infection to fully understand their in vivo impact
The DEEP Groth Strip Galaxy Redshift Survey. III. Redshift Catalog and Properties of Galaxies
The Deep Extragalactic Evolutionary Probe (DEEP) is a series of spectroscopic
surveys of faint galaxies, targeted at the properties and clustering of
galaxies at redshifts z ~ 1. We present the redshift catalog of the DEEP 1 GSS
pilot phase of this project, a Keck/LRIS survey in the HST/WFPC2 Groth Survey
Strip. The redshift catalog and data, including reduced spectra, are publicly
available through a Web-accessible database. The catalog contains 658 secure
galaxy redshifts with a median z=0.65, and shows large-scale structure walls to
z = 1. We find a bimodal distribution in the galaxy color-magnitude diagram
which persists to z = 1. A similar color division has been seen locally by the
SDSS and to z ~ 1 by COMBO-17. For red galaxies, we find a reddening of only
0.11 mag from z ~ 0.8 to now, about half the color evolution measured by
COMBO-17. We measure structural properties of the galaxies from the HST
imaging, and find that the color division corresponds generally to a structural
division. Most red galaxies, ~ 75%, are centrally concentrated, with a red
bulge or spheroid, while blue galaxies usually have exponential profiles.
However, there are two subclasses of red galaxies that are not bulge-dominated:
edge-on disks and a second category which we term diffuse red galaxies
(DIFRGs). The distant edge-on disks are similar in appearance and frequency to
those at low redshift, but analogs of DIFRGs are rare among local red galaxies.
DIFRGs have significant emission lines, indicating that they are reddened
mainly by dust rather than age. The DIFRGs in our sample are all at z>0.64,
suggesting that DIFRGs are more prevalent at high redshifts; they may be
related to the dusty or irregular extremely red objects (EROs) beyond z>1.2
that have been found in deep K-selected surveys. (abridged)Comment: ApJ in press. 24 pages, 17 figures (12 color). The DEEP public
database is available at http://saci.ucolick.org
Editor's choice : European Society for Vascular Surgery (ESVS) 2020 clinical practice guidelines on the management of acute limb ischaemia
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Aptamer-based multiplexed proteomic technology for biomarker discovery
Interrogation of the human proteome in a highly multiplexed and efficient manner remains a coveted and challenging goal in biology. We present a new aptamer-based proteomic technology for biomarker discovery capable of simultaneously measuring thousands of proteins from small sample volumes (15 [mu]L of serum or plasma). Our current assay allows us to measure ~800 proteins with very low limits of detection (1 pM average), 7 logs of overall dynamic range, and 5% average coefficient of variation. This technology is enabled by a new generation of aptamers that contain chemically modified nucleotides, which greatly expand the physicochemical diversity of the large randomized nucleic acid libraries from which the aptamers are selected. Proteins in complex matrices such as plasma are measured with a process that transforms a signature of protein concentrations into a corresponding DNA aptamer concentration signature, which is then quantified with a DNA microarray. In essence, our assay takes advantage of the dual nature of aptamers as both folded binding entities with defined shapes and unique sequences recognizable by specific hybridization probes. To demonstrate the utility of our proteomics biomarker discovery technology, we applied it to a clinical study of chronic kidney disease (CKD). We identified two well known CKD biomarkers as well as an additional 58 potential CKD biomarkers. These results demonstrate the potential utility of our technology to discover unique protein signatures characteristic of various disease states. More generally, we describe a versatile and powerful tool that allows large-scale comparison of proteome profiles among discrete populations. This unbiased and highly multiplexed search engine will enable the discovery of novel biomarkers in a manner that is unencumbered by our incomplete knowledge of biology, thereby helping to advance the next generation of evidence-based medicine
A framework for assistive communications technology in cross-cultural healthcare
Rural and remote Australian Aboriginal communities suffer seriously adverse life expectancy rates, lifestyle disease complications and hospital treatment needs due to type 2 diabetes. In great part this is due to communications barriers arising from the lack of equitable acculturation within patient-practitioner consultations. This research presents a framework foundation for a computerised patient-practitioner lingua franca. Behavioural and design science ontology development delivers an intercultural patient-practitioner type 2 diabetes assistive communications system, known as P-PAC
Progress report no. 3
Statement of responsibility on title-page reads: editors: M.J. Driscoll, D.D. Lanning, I. Kaplan; contributors: S. T. Brewer, G.J. Brown, P. Delaquil, M.J. Driscoll, G.A. Ducat, I.A. Forbes, M. V. Gregory, S.Y. Ho, M.S. Kalra, C.S. Kang, L.T. Kim, D.D. Lanning, J.L. Lazewatsky, T.C. Leung, E.A. Mason, N.R. Ortiz, N.C. Rasmussen, I.C. Rickard, K.D. Roberson, A.T. Supple, A.M. Thompson, and C.P. TzanosIncludes bibliographical referencesProgress report ; June 30, 1972U.S. Atomic Energy Commission contracts: AT(11-1)306
Progress report no. 2
Statement of responsibility on title-page reads: Editors: I.A. Forbes, M.J. Driscoll, N.C. Rasmussen, D.D. Lanning and I. Kaplan; Contributors: S.T. Brewer, G.J. Brown, P.DeLaquil, III, M.J. Driscoll, I.A. Forbes, C.W. Forsberg, E.P. Gyftopoulos, P.L. Hendrick, C.S. Kang, I. Kaplan, J.L. Klucar, D.D. Lanning, T.C. Leung, E.A. Mason, N.R. Ortiz, N.A. Passman, N.C. Rasmussen, I.C. Rickard, V.C. Rogers, G.E. Sullivan, A.T. Supple, and C. P. TzanosIncludes bibliographical referencesProgress report; June 30, 1971U.S. Atomic Energy Commission contract AT(11-1)306
The Illustrated History of the Riverine Force: The Vietnam War, The Illustrated History of Carrier Operations: The Vietnam War, and The Illustrated History of the Marines: The Vietnam War
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