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  • ASTROPHYSICS  (16)
  • Analytical Chemistry and Spectroscopy  (6)
  • Molecular Sequence Data  (5)
  • 1
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    Resistance to therapy caused by intragenic deletion in BRCA2 (2008)
    Nature Publishing Group (NPG)
    Details
    Publication Date: 2008-02-12
    Description: Cells with loss of BRCA2 function are defective in homologous recombination (HR) and are highly sensitive to inhibitors of poly(ADP-ribose) polymerase (PARP), which provides the basis for a new therapeutic approach. Here we show that resistance to PARP inhibition can be acquired by deletion of a mutation in BRCA2. We derived PARP-inhibitor-resistant (PIR) clones from the human CAPAN1 pancreatic cancer cell line, which carries the protein-truncating c.6174delT frameshift mutation. PIR clones could form DNA-damage-induced RAD51 nuclear foci and were able to limit genotoxin-induced genomic instability, both hallmarks of a competent HR pathway. New BRCA2 isoforms were expressed in the resistant lines as a result of intragenic deletion of the c.6174delT mutation and restoration of the open reading frame (ORF). Reconstitution of BRCA2-deficient cells with these revertant BRCA2 alleles rescued PARP inhibitor sensitivity and HR deficiency. Most of the deletions in BRCA2 were associated with small tracts of homology, and possibly arose from error-prone repair caused by BRCA2 deficiency. Similar ORF-restoring mutations were present in carboplatin-resistant ovarian tumours from c.6174delT mutation carriers. These observations have implications for understanding drug resistance in BRCA mutation carriers as well as in defining functionally important domains within BRCA2.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Edwards, Stacey L -- Brough, Rachel -- Lord, Christopher J -- Natrajan, Rachael -- Vatcheva, Radost -- Levine, Douglas A -- Boyd, Jeff -- Reis-Filho, Jorge S -- Ashworth, Alan -- A8363/Cancer Research UK/United Kingdom -- England -- Nature. 2008 Feb 28;451(7182):1111-5. doi: 10.1038/nature06548. Epub 2008 Feb 10.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉The Breakthrough Breast Cancer Research Centre, The Institute of Cancer Research, Fulham Road, London SW3 6JB, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18264088" target="_blank"〉PubMed〈/a〉
    Keywords: Aged ; Alleles ; Amino Acid Sequence ; BRCA2 Protein/deficiency/genetics ; Base Sequence ; Carboplatin/pharmacology ; Cell Line, Tumor ; Chromosome Aberrations/chemically induced ; Drug Resistance, Neoplasm/*drug effects/*genetics ; Female ; Fluorobenzenes/pharmacology ; Gene Expression Regulation, Neoplastic ; *Genes, BRCA2 ; Humans ; Middle Aged ; Mitomycin/pharmacology ; Molecular Sequence Data ; Mutation/genetics ; Open Reading Frames/genetics ; Ovarian Neoplasms/drug therapy/genetics ; Pancreatic Neoplasms/drug therapy/genetics/pathology ; Phthalazines/pharmacology ; Poly(ADP-ribose) Polymerase Inhibitors ; Recombination, Genetic/genetics ; Sequence Deletion/*genetics
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Published by Nature Publishing Group (NPG)
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  • 2
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    The genome of the kinetoplastid parasite, Leishmania major (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-07-16
    Description: Leishmania species cause a spectrum of human diseases in tropical and subtropical regions of the world. We have sequenced the 36 chromosomes of the 32.8-megabase haploid genome of Leishmania major (Friedlin strain) and predict 911 RNA genes, 39 pseudogenes, and 8272 protein-coding genes, of which 36% can be ascribed a putative function. These include genes involved in host-pathogen interactions, such as proteolytic enzymes, and extensive machinery for synthesis of complex surface glycoconjugates. The organization of protein-coding genes into long, strand-specific, polycistronic clusters and lack of general transcription factors in the L. major, Trypanosoma brucei, and Trypanosoma cruzi (Tritryp) genomes suggest that the mechanisms regulating RNA polymerase II-directed transcription are distinct from those operating in other eukaryotes, although the trypanosomatids appear capable of chromatin remodeling. Abundant RNA-binding proteins are encoded in the Tritryp genomes, consistent with active posttranscriptional regulation of gene expression.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1470643/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1470643/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Ivens, Alasdair C -- Peacock, Christopher S -- Worthey, Elizabeth A -- Murphy, Lee -- Aggarwal, Gautam -- Berriman, Matthew -- Sisk, Ellen -- Rajandream, Marie-Adele -- Adlem, Ellen -- Aert, Rita -- Anupama, Atashi -- Apostolou, Zina -- Attipoe, Philip -- Bason, Nathalie -- Bauser, Christopher -- Beck, Alfred -- Beverley, Stephen M -- Bianchettin, Gabriella -- Borzym, Katja -- Bothe, Gordana -- Bruschi, Carlo V -- Collins, Matt -- Cadag, Eithon -- Ciarloni, Laura -- Clayton, Christine -- Coulson, Richard M R -- Cronin, Ann -- Cruz, Angela K -- Davies, Robert M -- De Gaudenzi, Javier -- Dobson, Deborah E -- Duesterhoeft, Andreas -- Fazelina, Gholam -- Fosker, Nigel -- Frasch, Alberto Carlos -- Fraser, Audrey -- Fuchs, Monika -- Gabel, Claudia -- Goble, Arlette -- Goffeau, Andre -- Harris, David -- Hertz-Fowler, Christiane -- Hilbert, Helmut -- Horn, David -- Huang, Yiting -- Klages, Sven -- Knights, Andrew -- Kube, Michael -- Larke, Natasha -- Litvin, Lyudmila -- Lord, Angela -- Louie, Tin -- Marra, Marco -- Masuy, David -- Matthews, Keith -- Michaeli, Shulamit -- Mottram, Jeremy C -- Muller-Auer, Silke -- Munden, Heather -- Nelson, Siri -- Norbertczak, Halina -- Oliver, Karen -- O'neil, Susan -- Pentony, Martin -- Pohl, Thomas M -- Price, Claire -- Purnelle, Benedicte -- Quail, Michael A -- Rabbinowitsch, Ester -- Reinhardt, Richard -- Rieger, Michael -- Rinta, Joel -- Robben, Johan -- Robertson, Laura -- Ruiz, Jeronimo C -- Rutter, Simon -- Saunders, David -- Schafer, Melanie -- Schein, Jacquie -- Schwartz, David C -- Seeger, Kathy -- Seyler, Amber -- Sharp, Sarah -- Shin, Heesun -- Sivam, Dhileep -- Squares, Rob -- Squares, Steve -- Tosato, Valentina -- Vogt, Christy -- Volckaert, Guido -- Wambutt, Rolf -- Warren, Tim -- Wedler, Holger -- Woodward, John -- Zhou, Shiguo -- Zimmermann, Wolfgang -- Smith, Deborah F -- Blackwell, Jenefer M -- Stuart, Kenneth D -- Barrell, Bart -- Myler, Peter J -- R01 AI040599/AI/NIAID NIH HHS/ -- R01 AI053667/AI/NIAID NIH HHS/ -- U01 AI040599/AI/NIAID NIH HHS/ -- Wellcome Trust/United Kingdom -- New York, N.Y. -- Science. 2005 Jul 15;309(5733):436-42.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridgeshire CB10 1SA, UK. alicat@sanger.ac.uk〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16020728" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Chromatin/genetics/metabolism ; Gene Expression Regulation ; Genes, Protozoan ; Genes, rRNA ; *Genome, Protozoan ; Glycoconjugates/biosynthesis/metabolism ; Leishmania major/chemistry/*genetics/metabolism ; Leishmaniasis, Cutaneous/parasitology ; Lipid Metabolism ; Membrane Proteins/biosynthesis/chemistry/genetics/metabolism ; Molecular Sequence Data ; Multigene Family ; Protein Biosynthesis ; Protein Processing, Post-Translational ; Protozoan Proteins/biosynthesis/chemistry/genetics/metabolism ; RNA Processing, Post-Transcriptional ; RNA Splicing ; RNA, Protozoan/genetics/metabolism ; *Sequence Analysis, DNA ; Transcription, Genetic
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
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  • 3
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    Genome of the host-cell transforming parasite Theileria annulata compared with T. parva (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-07-05
    Description: Theileria annulata and T. parva are closely related protozoan parasites that cause lymphoproliferative diseases of cattle. We sequenced the genome of T. annulata and compared it with that of T. parva to understand the mechanisms underlying transformation and tropism. Despite high conservation of gene sequences and synteny, the analysis reveals unequally expanded gene families and species-specific genes. We also identify divergent families of putative secreted polypeptides that may reduce immune recognition, candidate regulators of host-cell transformation, and a Theileria-specific protein domain [frequently associated in Theileria (FAINT)] present in a large number of secreted proteins.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Pain, Arnab -- Renauld, Hubert -- Berriman, Matthew -- Murphy, Lee -- Yeats, Corin A -- Weir, William -- Kerhornou, Arnaud -- Aslett, Martin -- Bishop, Richard -- Bouchier, Christiane -- Cochet, Madeleine -- Coulson, Richard M R -- Cronin, Ann -- de Villiers, Etienne P -- Fraser, Audrey -- Fosker, Nigel -- Gardner, Malcolm -- Goble, Arlette -- Griffiths-Jones, Sam -- Harris, David E -- Katzer, Frank -- Larke, Natasha -- Lord, Angela -- Maser, Pascal -- McKellar, Sue -- Mooney, Paul -- Morton, Fraser -- Nene, Vishvanath -- O'Neil, Susan -- Price, Claire -- Quail, Michael A -- Rabbinowitsch, Ester -- Rawlings, Neil D -- Rutter, Simon -- Saunders, David -- Seeger, Kathy -- Shah, Trushar -- Squares, Robert -- Squares, Steven -- Tivey, Adrian -- Walker, Alan R -- Woodward, John -- Dobbelaere, Dirk A E -- Langsley, Gordon -- Rajandream, Marie-Adele -- McKeever, Declan -- Shiels, Brian -- Tait, Andrew -- Barrell, Bart -- Hall, Neil -- Wellcome Trust/United Kingdom -- New York, N.Y. -- Science. 2005 Jul 1;309(5731):131-3.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK. ap2@sanger.ac.uk〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15994557" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Motifs ; Animals ; Cattle ; Cell Proliferation ; Chromosome Mapping ; Chromosomes/genetics ; Conserved Sequence ; Genes, Protozoan ; *Genome, Protozoan ; Life Cycle Stages ; Lipid Metabolism ; Lymphocytes/cytology/parasitology ; Molecular Sequence Data ; Multigene Family ; Phylogeny ; Protein Sorting Signals/genetics ; Protein Structure, Tertiary ; Proteome ; Protozoan Proteins/chemistry/*genetics/physiology ; Sequence Analysis, DNA ; Species Specificity ; Synteny ; Telomere/genetics ; Theileria annulata/*genetics/growth & development/immunology/pathogenicity ; Theileria parva/*genetics/growth & development/immunology/pathogenicity
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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  • 4
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    Extensive DNA inversions in the B. fragilis genome control variable gene expression (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-03-05
    Description: The obligately anaerobic bacterium Bacteroides fragilis, an opportunistic pathogen and inhabitant of the normal human colonic microbiota, exhibits considerable within-strain phase and antigenic variation of surface components. The complete genome sequence has revealed an unusual breadth (in number and in effect) of DNA inversion events that potentially control expression of many different components, including surface and secreted components, regulatory molecules, and restriction-modification proteins. Invertible promoters of two different types (12 group 1 and 11 group 2) were identified. One group has inversion crossover (fix) sites similar to the hix sites of Salmonella typhimurium. There are also four independent intergenic shufflons that potentially alter the expression and function of varied genes. The composition of the 10 different polysaccharide biosynthesis gene clusters identified (7 with associated invertible promoters) suggests a mechanism of synthesis similar to the O-antigen capsules of Escherichia coli.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Cerdeno-Tarraga, Ana M -- Patrick, Sheila -- Crossman, Lisa C -- Blakely, Garry -- Abratt, Val -- Lennard, Nicola -- Poxton, Ian -- Duerden, Brian -- Harris, Barbara -- Quail, Mike A -- Barron, Andrew -- Clark, Louise -- Corton, Craig -- Doggett, Jonathan -- Holden, Matthew T G -- Larke, Natasha -- Line, Alexandra -- Lord, Angela -- Norbertczak, Halina -- Ormond, Doug -- Price, Claire -- Rabbinowitsch, Ester -- Woodward, John -- Barrell, Bart -- Parkhill, Julian -- New York, N.Y. -- Science. 2005 Mar 4;307(5714):1463-5.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15746427" target="_blank"〉PubMed〈/a〉
    Keywords: Bacterial Outer Membrane Proteins/genetics ; Bacteroides fragilis/*genetics/metabolism/pathogenicity ; Base Sequence ; Chromosome Inversion ; DNA, Bacterial/*genetics ; DNA, Intergenic ; *Gene Expression Regulation, Bacterial ; *Genome, Bacterial ; Molecular Sequence Data ; Polysaccharides, Bacterial/biosynthesis/genetics ; Promoter Regions, Genetic ; Recombinases/genetics ; Recombination, Genetic ; Repetitive Sequences, Nucleic Acid ; Transcription, Genetic
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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  • 5
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    The genome of the African trypanosome Trypanosoma brucei (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2005-07-16
    Description: African trypanosomes cause human sleeping sickness and livestock trypanosomiasis in sub-Saharan Africa. We present the sequence and analysis of the 11 megabase-sized chromosomes of Trypanosoma brucei. The 26-megabase genome contains 9068 predicted genes, including approximately 900 pseudogenes and approximately 1700 T. brucei-specific genes. Large subtelomeric arrays contain an archive of 806 variant surface glycoprotein (VSG) genes used by the parasite to evade the mammalian immune system. Most VSG genes are pseudogenes, which may be used to generate expressed mosaic genes by ectopic recombination. Comparisons of the cytoskeleton and endocytic trafficking systems with those of humans and other eukaryotic organisms reveal major differences. A comparison of metabolic pathways encoded by the genomes of T. brucei, T. cruzi, and Leishmania major reveals the least overall metabolic capability in T. brucei and the greatest in L. major. Horizontal transfer of genes of bacterial origin has contributed to some of the metabolic differences in these parasites, and a number of novel potential drug targets have been identified.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Berriman, Matthew -- Ghedin, Elodie -- Hertz-Fowler, Christiane -- Blandin, Gaelle -- Renauld, Hubert -- Bartholomeu, Daniella C -- Lennard, Nicola J -- Caler, Elisabet -- Hamlin, Nancy E -- Haas, Brian -- Bohme, Ulrike -- Hannick, Linda -- Aslett, Martin A -- Shallom, Joshua -- Marcello, Lucio -- Hou, Lihua -- Wickstead, Bill -- Alsmark, U Cecilia M -- Arrowsmith, Claire -- Atkin, Rebecca J -- Barron, Andrew J -- Bringaud, Frederic -- Brooks, Karen -- Carrington, Mark -- Cherevach, Inna -- Chillingworth, Tracey-Jane -- Churcher, Carol -- Clark, Louise N -- Corton, Craig H -- Cronin, Ann -- Davies, Rob M -- Doggett, Jonathon -- Djikeng, Appolinaire -- Feldblyum, Tamara -- Field, Mark C -- Fraser, Audrey -- Goodhead, Ian -- Hance, Zahra -- Harper, David -- Harris, Barbara R -- Hauser, Heidi -- Hostetler, Jessica -- Ivens, Al -- Jagels, Kay -- Johnson, David -- Johnson, Justin -- Jones, Kristine -- Kerhornou, Arnaud X -- Koo, Hean -- Larke, Natasha -- Landfear, Scott -- Larkin, Christopher -- Leech, Vanessa -- Line, Alexandra -- Lord, Angela -- Macleod, Annette -- Mooney, Paul J -- Moule, Sharon -- Martin, David M A -- Morgan, Gareth W -- Mungall, Karen -- Norbertczak, Halina -- Ormond, Doug -- Pai, Grace -- Peacock, Chris S -- Peterson, Jeremy -- Quail, Michael A -- Rabbinowitsch, Ester -- Rajandream, Marie-Adele -- Reitter, Chris -- Salzberg, Steven L -- Sanders, Mandy -- Schobel, Seth -- Sharp, Sarah -- Simmonds, Mark -- Simpson, Anjana J -- Tallon, Luke -- Turner, C Michael R -- Tait, Andrew -- Tivey, Adrian R -- Van Aken, Susan -- Walker, Danielle -- Wanless, David -- Wang, Shiliang -- White, Brian -- White, Owen -- Whitehead, Sally -- Woodward, John -- Wortman, Jennifer -- Adams, Mark D -- Embley, T Martin -- Gull, Keith -- Ullu, Elisabetta -- Barry, J David -- Fairlamb, Alan H -- Opperdoes, Fred -- Barrell, Barclay G -- Donelson, John E -- Hall, Neil -- Fraser, Claire M -- Melville, Sara E -- El-Sayed, Najib M -- AI43062/AI/NIAID NIH HHS/ -- R01 AI043062/AI/NIAID NIH HHS/ -- U01 AI043062/AI/NIAID NIH HHS/ -- Wellcome Trust/United Kingdom -- New York, N.Y. -- Science. 2005 Jul 15;309(5733):416-22.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK. mb4@sanger.ac.uk〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16020726" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acids/metabolism ; Animals ; Antigenic Variation ; Antigens, Protozoan/chemistry/genetics/immunology ; Carbohydrate Metabolism ; Chromosomes/genetics ; Cytoskeleton/chemistry/genetics/physiology ; Ergosterol/biosynthesis ; Genes, Protozoan ; *Genome, Protozoan ; Glutathione/*analogs & derivatives/metabolism ; Glycosylphosphatidylinositols/biosynthesis ; Humans ; Lipid Metabolism ; Molecular Sequence Data ; Protein Transport ; Protozoan Proteins/chemistry/*genetics/metabolism ; Pseudogenes ; Purines/metabolism ; Pyrimidines/biosynthesis ; Recombination, Genetic ; *Sequence Analysis, DNA ; Spermidine/*analogs & derivatives/metabolism ; Trypanosoma brucei brucei/chemistry/*genetics/immunology/metabolism ; Trypanosomiasis, African/parasitology
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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  • 6
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    Nebular properties from far-infrared spectrosopy (1994)
    In:  Other Sources
    Details
    Publication Date: 2011-08-24
    Description: We describe a semiempirical methodology-based on measurements of far-infrared (FIR) lines-that yields information on electron densities in regions where various ionic species exist, effective temperatures (T(sub eff)) for stars ionizing H II regions, and gas-phase heavy element abundances. Although this capability has long been available via optical data, the special features of FIR lines-relative insensitivity to extinction and electron temperature variations-extend the analysis ability. Several line ratios serve as diagnostics of electron density, N(sub e), probing different ionization conditions and different density regimes. The more N(sub e)-diagnostic observations made, the more reliable will be the deciphering of the actual variation in density throughout a nebula. A method to estimate T(sub eff) from the FIR (N III)/(N II) line ratio requires that the nebula be ionization bounded and that substantially all of the flux from the revevant lines be observed. However, to estimate T(sub eff) by a second method that uses the ratio of FIR (S III)/(O III) lines, an ionization-bounded nebula is a sufficient, but not necessary, condition. These restrictions are unnecessary for estimating densities and heavy element abundances. We show that a fairly general determination of metallicity, via the S/H ratio, may be made for H II regions with observations of just two lines-(S III) 19 micron and a hydrogen recombination line (or appropriate substitute). These techniques are applied to recent FIR data for the G333.6-0.2 H II region, including application to the recently measured (N II) 122 and 205 micron lines.
    Keywords: ASTROPHYSICS
    Type: The Astrophysical Journal, Part 1 (ISSN 0004-637X); 420; 2; p. 772-782
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  • 7
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    Efficient star formation in the spiral arms of M51 (1990)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Description: The molecular, neutral, and ionized hydrogen distributions in the Sbc galaxy M51 (NGC 5194) are compared. To estimate H2 surface densities observations of the CO (J = 1 - 0) transition were made in 60 positions out to a radius of 155 arcsec. Extinction-corrected H-alpha intensities were used to compute the detailed massive star formation rates (MSFRs) in the disk. Estimates of the gas surface density, the MSFR, and the ratio of these quantities, MSFR/sigma(p), were then examined. The spiral arms were found to exhibit an excess gas density, measuring between 1.4 and 1.6 times the interarm values at 45 arcsec resolution. The total (arm and interarm) gas content and massive star formation rates in concentric annuli in the disk of M51 were computed. The two quantities fall off together with radius, yielding a relatively constant MSFR/sigma(p) with radius. This behavior is not explained by current models of star formation in galactic disks.
    Keywords: ASTROPHYSICS
    Type: Astrophysical Journal, Part 1 (ISSN 0004-637X); 356; 135-148
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  • 8
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    CO observations of infrared bright galaxies - The efficiency of star formation (1986)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Description: CO emission has been detected in each of 14 of the IR-bright galaxies listed in IRAS Circular 15; for the nine galaxies of the largest angular size, the CO emission distributions along the major axis have been mapped. A strong correlation is noted between total CO luminosities and IR ones for galaxies in each of three ranges of dust temperature. The ratio of IR/CO luminosities increases with the ratio of 60/100-micron flux densities, consistent with emission of thermal origin at the characteristic temperature given by the dust temperature. If this luminosity ratio is a measure of the emergent stellar luminosity/unit molecular mass, or the efficiency of star formation, this efficiency varies over almost two orders of magnitude from one galaxy to another.
    Keywords: ASTROPHYSICS
    Type: Astrophysical Journal, Part 1 (ISSN 0004-637X); 304; 443-458
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  • 9
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    Observation of Fe II (26.0 microns) in SN 1987A (1988)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Description: The first observation of the 26-micron line from singly ionized iron in SN 1987A is reported. The total flux is 4.5 + or - 0.9 x 20 to the -18th W/sq cm. The line width (FWHM) is 4000 + or - 600 km/s. The minimum iron mass is found to be about 0.02 solar, indicating that the emission originates in the heavy element mantle and not in the hydrogen-rich envelope. Since this mass is less than estimates based on near-infrared measurements or the optical light curve, the emission is probably optically thick. In this case, the flux measurement together with the observed line width suggest a temperature of 3500 + or - 1500 K for the mantle. The broad line width suggests that mixing of the ejected iron with lighter elements in overlying layers has occurred.
    Keywords: ASTROPHYSICS
    Type: Astrophysical Journal, Part 2 - Letters (ISSN 0004-637X); 330; L39-L41
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  • 10
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    A multiwavelength survey of interacting galaxies (1990)
    In:  CASI
    Details
    Publication Date: 2013-08-31
    Description: Galaxy-galaxy collisions are known to produce drastic changes in morphology and, in many cases, enhance the level of star formation activity in galaxies. In order to better quantify the effects that interactions have on the star formation characteristics of galaxies the authors undertook a multiwavelength survey of a large sample of interacting disk-type galaxies. The sample is optically-selected, the inclusion of systems having been based upon the presence of unusual morphological features--such as tidal tails, plumes, rings, warped disks--suggestive of tidal interaction. The sample is composed of about 115 systems, most of which are spiral-spiral pairs, with a few spiral-elliptical pairs and a few merging systems (see Bushouse 1986 for more details of the sample selection). This sample has now been studied in the optical, infrared, and radio regimes, including optical spectra and H alpha images, near-infrared photometry and imaging, far-infrared photometry, H I 21 cm emission-line measurements, Very Large Array (VLA) 20 cm maps, and CO emission-line measurements. This paper presents an overview and comparison of the results of the optical, infrared and CO surveys. With these data the authors can compare the far-infrared and CO properties of the galaxies with the classic optical and radio indicators of star formation activity and thereby determine what, if any, relationships exist between star formation activity and the far-infrared and CO properties of the galaxies.
    Keywords: ASTROPHYSICS
    Type: NASA, Marshall Space Flight Center, Paired and Interacting Galaxies: International Astronomical Union Colloquium No. 124; p 285-290
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