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  • Articles  (627)
  • Chemical Engineering  (377)
  • Amino Acid Sequence  (250)
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  • 1995-1999  (395)
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  • 1
    Publication Date: 2016-03-05
    Description: The most recent Ebola virus outbreak in West Africa, which was unprecedented in the number of cases and fatalities, geographic distribution, and number of nations affected, highlights the need for safe, effective, and readily available antiviral agents for treatment and prevention of acute Ebola virus (EBOV) disease (EVD) or sequelae. No antiviral therapeutics have yet received regulatory approval or demonstrated clinical efficacy. Here we report the discovery of a novel small molecule GS-5734, a monophosphoramidate prodrug of an adenosine analogue, with antiviral activity against EBOV. GS-5734 exhibits antiviral activity against multiple variants of EBOV and other filoviruses in cell-based assays. The pharmacologically active nucleoside triphosphate (NTP) is efficiently formed in multiple human cell types incubated with GS-5734 in vitro, and the NTP acts as an alternative substrate and RNA-chain terminator in primer-extension assays using a surrogate respiratory syncytial virus RNA polymerase. Intravenous administration of GS-5734 to nonhuman primates resulted in persistent NTP levels in peripheral blood mononuclear cells (half-life, 14 h) and distribution to sanctuary sites for viral replication including testes, eyes, and brain. In a rhesus monkey model of EVD, once-daily intravenous administration of 10 mg kg(-1) GS-5734 for 12 days resulted in profound suppression of EBOV replication and protected 100% of EBOV-infected animals against lethal disease, ameliorating clinical disease signs and pathophysiological markers, even when treatments were initiated three days after virus exposure when systemic viral RNA was detected in two out of six treated animals. These results show the first substantive post-exposure protection by a small-molecule antiviral compound against EBOV in nonhuman primates. The broad-spectrum antiviral activity of GS-5734 in vitro against other pathogenic RNA viruses, including filoviruses, arenaviruses, and coronaviruses, suggests the potential for wider medical use. GS-5734 is amenable to large-scale manufacturing, and clinical studies investigating the drug safety and pharmacokinetics are ongoing.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Warren, Travis K -- Jordan, Robert -- Lo, Michael K -- Ray, Adrian S -- Mackman, Richard L -- Soloveva, Veronica -- Siegel, Dustin -- Perron, Michel -- Bannister, Roy -- Hui, Hon C -- Larson, Nate -- Strickley, Robert -- Wells, Jay -- Stuthman, Kelly S -- Van Tongeren, Sean A -- Garza, Nicole L -- Donnelly, Ginger -- Shurtleff, Amy C -- Retterer, Cary J -- Gharaibeh, Dima -- Zamani, Rouzbeh -- Kenny, Tara -- Eaton, Brett P -- Grimes, Elizabeth -- Welch, Lisa S -- Gomba, Laura -- Wilhelmsen, Catherine L -- Nichols, Donald K -- Nuss, Jonathan E -- Nagle, Elyse R -- Kugelman, Jeffrey R -- Palacios, Gustavo -- Doerffler, Edward -- Neville, Sean -- Carra, Ernest -- Clarke, Michael O -- Zhang, Lijun -- Lew, Willard -- Ross, Bruce -- Wang, Queenie -- Chun, Kwon -- Wolfe, Lydia -- Babusis, Darius -- Park, Yeojin -- Stray, Kirsten M -- Trancheva, Iva -- Feng, Joy Y -- Barauskas, Ona -- Xu, Yili -- Wong, Pamela -- Braun, Molly R -- Flint, Mike -- McMullan, Laura K -- Chen, Shan-Shan -- Fearns, Rachel -- Swaminathan, Swami -- Mayers, Douglas L -- Spiropoulou, Christina F -- Lee, William A -- Nichol, Stuart T -- Cihlar, Tomas -- Bavari, Sina -- R01 AI113321/AI/NIAID NIH HHS/ -- R01AI113321/AI/NIAID NIH HHS/ -- England -- Nature. 2016 Mar 17;531(7594):381-5. doi: 10.1038/nature17180. Epub 2016 Mar 2.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland 21702, USA. ; United States Army Medical Research Institute of Infectious Diseases, Therapeutic Development Center, Frederick, Maryland 21702, USA. ; Gilead Sciences, Foster City, California 94404, USA. ; Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA. ; Boston University School of Medicine, Boston, Massachusetts 02118, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26934220" target="_blank"〉PubMed〈/a〉
    Keywords: Alanine/*analogs & derivatives/pharmacokinetics/pharmacology/therapeutic use ; Amino Acid Sequence ; Animals ; Antiviral Agents/pharmacokinetics/pharmacology/*therapeutic use ; Cell Line, Tumor ; Ebolavirus/drug effects ; Female ; HeLa Cells ; Hemorrhagic Fever, Ebola/*drug therapy/prevention & control ; Humans ; Macaca mulatta/*virology ; Male ; Molecular Sequence Data ; Organ Specificity ; Prodrugs/pharmacokinetics/pharmacology/therapeutic use ; Ribonucleotides/pharmacokinetics/pharmacology/*therapeutic use
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
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  • 2
    Publication Date: 1995-12-15
    Description: The rice Xa21 gene, which confers resistance to Xanthomonas oryzae pv. oryzae race 6, was isolated by positional cloning. Fifty transgenic rice plants carrying the cloned Xa21 gene display high levels of resistance to the pathogen. The sequence of the predicted protein, which carries both a leucine-rich repeat motif and a serine-threonine kinase-like domain, suggests a role in cell surface recognition of a pathogen ligand and subsequent activation of an intracellular defense response. Characterization of Xa21 should facilitate understanding of plant disease resistance and lead to engineered resistance in rice.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Song, W Y -- Wang, G L -- Chen, L L -- Kim, H S -- Pi, L Y -- Holsten, T -- Gardner, J -- Wang, B -- Zhai, W X -- Zhu, L H -- Fauquet, C -- Ronald, P -- New York, N.Y. -- Science. 1995 Dec 15;270(5243):1804-6.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Plant Pathology, University of California, Davis 95616, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/8525370" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Cloning, Molecular ; *Genes, Plant ; Genetic Linkage ; Molecular Sequence Data ; Oryza/enzymology/*genetics/microbiology ; Plant Diseases ; Plant Proteins/*genetics/metabolism ; Plants, Genetically Modified ; Protein-Serine-Threonine Kinases/*genetics/metabolism ; Receptor Protein-Tyrosine Kinases ; Receptors, Cell Surface/*genetics/metabolism ; Xanthomonas/physiology
    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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  • 3
    Publication Date: 1995-11-17
    Description: Strategies for the treatment of human immunodeficiency virus-type 1 (HIV-1) infection must contend with the obstacle of drug resistance. HIV-1 nucleocapsid protein zinc fingers are prime antiviral targets because they are mutationally intolerant and are required both for acute infection and virion assembly. Nontoxic disulfide-substituted benzamides were identified that attack the zinc fingers, inactivate cell-free virions, inhibit acute and chronic infections, and exhibit broad antiretroviral activity. The compounds were highly synergistic with other antiviral agents, and resistant mutants have not been detected. Zinc finger-reactive compounds may offer an anti-HIV strategy that restricts drug-resistance development.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Rice, W G -- Supko, J G -- Malspeis, L -- Buckheit, R W Jr -- Clanton, D -- Bu, M -- Graham, L -- Schaeffer, C A -- Turpin, J A -- Domagala, J -- Gogliotti, R -- Bader, J P -- Halliday, S M -- Coren, L -- Sowder, R C 2nd -- Arthur, L O -- Henderson, L E -- New York, N.Y. -- Science. 1995 Nov 17;270(5239):1194-7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Laboratory of Antiviral Drug Mechanisms, PRI/DynCorp., National Cancer Institute-Frederick Cancer Research and Development Center, MD 21702, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/7502043" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Animals ; Antiviral Agents/chemistry/pharmacokinetics/*pharmacology ; Benzamides/chemistry/pharmacokinetics/*pharmacology ; Biological Availability ; Capsid/chemistry/*metabolism ; *Capsid Proteins ; Cell Line ; Disulfides/chemistry/pharmacokinetics/*pharmacology ; Drug Resistance, Microbial ; Drug Synergism ; Gene Products, gag/*antagonists & inhibitors/chemistry ; HIV-1/*drug effects/physiology ; Humans ; Male ; Mice ; Molecular Sequence Data ; *Viral Proteins ; Zinc Fingers/*drug effects ; gag Gene Products, Human Immunodeficiency Virus
    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
    Publication Date: 1998-11-06
    Description: Chromosome 2 of Plasmodium falciparum was sequenced; this sequence contains 947,103 base pairs and encodes 210 predicted genes. In comparison with the Saccharomyces cerevisiae genome, chromosome 2 has a lower gene density, introns are more frequent, and proteins are markedly enriched in nonglobular domains. A family of surface proteins, rifins, that may play a role in antigenic variation was identified. The complete sequencing of chromosome 2 has shown that sequencing of the A+T-rich P. falciparum genome is technically feasible.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Gardner, M J -- Tettelin, H -- Carucci, D J -- Cummings, L M -- Aravind, L -- Koonin, E V -- Shallom, S -- Mason, T -- Yu, K -- Fujii, C -- Pederson, J -- Shen, K -- Jing, J -- Aston, C -- Lai, Z -- Schwartz, D C -- Pertea, M -- Salzberg, S -- Zhou, L -- Sutton, G G -- Clayton, R -- White, O -- Smith, H O -- Fraser, C M -- Adams, M D -- Venter, J C -- Hoffman, S L -- R01 AI40125-01/AI/NIAID NIH HHS/ -- New York, N.Y. -- Science. 1998 Nov 6;282(5391):1126-32.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institute for Genomic Research, Rockville, MD 20850, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/9804551" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Animals ; Antigens, Protozoan/chemistry/genetics ; Base Composition ; Chromosomes/*genetics ; Evolution, Molecular ; *Genes, Protozoan ; Genome, Protozoan ; Introns ; Membrane Proteins/chemistry/genetics ; Molecular Sequence Data ; Multigene Family ; Physical Chromosome Mapping ; Plasmodium falciparum/*genetics ; Protozoan Proteins/chemistry/*genetics ; RNA, Protozoan/genetics ; RNA, Transfer, Glu/genetics ; Repetitive Sequences, Nucleic Acid ; Reverse Transcriptase Polymerase Chain Reaction ; Sequence Alignment ; *Sequence Analysis, DNA
    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
    Publication Date: 1996-10-25
    Description: The human genome is thought to harbor 50,000 to 100,000 genes, of which about half have been sampled to date in the form of expressed sequence tags. An international consortium was organized to develop and map gene-based sequence tagged site markers on a set of two radiation hybrid panels and a yeast artificial chromosome library. More than 16,000 human genes have been mapped relative to a framework map that contains about 1000 polymorphic genetic markers. The gene map unifies the existing genetic and physical maps with the nucleotide and protein sequence databases in a fashion that should speed the discovery of genes underlying inherited human disease. The integrated resource is available through a site on the World Wide Web at http://www.ncbi.nlm.nih.gov/SCIENCE96/.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Schuler, G D -- Boguski, M S -- Stewart, E A -- Stein, L D -- Gyapay, G -- Rice, K -- White, R E -- Rodriguez-Tome, P -- Aggarwal, A -- Bajorek, E -- Bentolila, S -- Birren, B B -- Butler, A -- Castle, A B -- Chiannilkulchai, N -- Chu, A -- Clee, C -- Cowles, S -- Day, P J -- Dibling, T -- Drouot, N -- Dunham, I -- Duprat, S -- East, C -- Edwards, C -- Fan, J B -- Fang, N -- Fizames, C -- Garrett, C -- Green, L -- Hadley, D -- Harris, M -- Harrison, P -- Brady, S -- Hicks, A -- Holloway, E -- Hui, L -- Hussain, S -- Louis-Dit-Sully, C -- Ma, J -- MacGilvery, A -- Mader, C -- Maratukulam, A -- Matise, T C -- McKusick, K B -- Morissette, J -- Mungall, A -- Muselet, D -- Nusbaum, H C -- Page, D C -- Peck, A -- Perkins, S -- Piercy, M -- Qin, F -- Quackenbush, J -- Ranby, S -- Reif, T -- Rozen, S -- Sanders, C -- She, X -- Silva, J -- Slonim, D K -- Soderlund, C -- Sun, W L -- Tabar, P -- Thangarajah, T -- Vega-Czarny, N -- Vollrath, D -- Voyticky, S -- Wilmer, T -- Wu, X -- Adams, M D -- Auffray, C -- Walter, N A -- Brandon, R -- Dehejia, A -- Goodfellow, P N -- Houlgatte, R -- Hudson, J R Jr -- Ide, S E -- Iorio, K R -- Lee, W Y -- Seki, N -- Nagase, T -- Ishikawa, K -- Nomura, N -- Phillips, C -- Polymeropoulos, M H -- Sandusky, M -- Schmitt, K -- Berry, R -- Swanson, K -- Torres, R -- Venter, J C -- Sikela, J M -- Beckmann, J S -- Weissenbach, J -- Myers, R M -- Cox, D R -- James, M R -- Bentley, D -- Deloukas, P -- Lander, E S -- Hudson, T J -- HG00098/HG/NHGRI NIH HHS/ -- HG00206/HG/NHGRI NIH HHS/ -- HG00835/HG/NHGRI NIH HHS/ -- Wellcome Trust/United Kingdom -- etc. -- New York, N.Y. -- Science. 1996 Oct 25;274(5287):540-6.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, 8600 Rockville Pike, Bethesda, MD 20894, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/8849440" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Animals ; Base Sequence ; Cell Line ; *Chromosome Mapping ; Chromosomes, Artificial, Yeast ; Computer Communication Networks ; DNA, Complementary/genetics ; Databases, Factual ; Gene Expression ; Genetic Markers ; *Genome, Human ; *Human Genome Project ; Humans ; Multigene Family ; RNA, Messenger/genetics ; Sequence Homology, Nucleic Acid ; Sequence Tagged Sites
    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
    Publication Date: 2015-01-09
    Description: The mechanistic target of rapamycin complex 1 (mTORC1) protein kinase is a master growth regulator that responds to multiple environmental cues. Amino acids stimulate, in a Rag-, Ragulator-, and vacuolar adenosine triphosphatase-dependent fashion, the translocation of mTORC1 to the lysosomal surface, where it interacts with its activator Rheb. Here, we identify SLC38A9, an uncharacterized protein with sequence similarity to amino acid transporters, as a lysosomal transmembrane protein that interacts with the Rag guanosine triphosphatases (GTPases) and Ragulator in an amino acid-sensitive fashion. SLC38A9 transports arginine with a high Michaelis constant, and loss of SLC38A9 represses mTORC1 activation by amino acids, particularly arginine. Overexpression of SLC38A9 or just its Ragulator-binding domain makes mTORC1 signaling insensitive to amino acid starvation but not to Rag activity. Thus, SLC38A9 functions upstream of the Rag GTPases and is an excellent candidate for being an arginine sensor for the mTORC1 pathway.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4295826/" 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/PMC4295826/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Wang, Shuyu -- Tsun, Zhi-Yang -- Wolfson, Rachel L -- Shen, Kuang -- Wyant, Gregory A -- Plovanich, Molly E -- Yuan, Elizabeth D -- Jones, Tony D -- Chantranupong, Lynne -- Comb, William -- Wang, Tim -- Bar-Peled, Liron -- Zoncu, Roberto -- Straub, Christoph -- Kim, Choah -- Park, Jiwon -- Sabatini, Bernardo L -- Sabatini, David M -- AI47389/AI/NIAID NIH HHS/ -- F30 CA180754/CA/NCI NIH HHS/ -- F31 AG044064/AG/NIA NIH HHS/ -- F31 CA180271/CA/NCI NIH HHS/ -- R01 CA103866/CA/NCI NIH HHS/ -- R37 AI047389/AI/NIAID NIH HHS/ -- T32 GM007287/GM/NIGMS NIH HHS/ -- T32 GM007753/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- New York, N.Y. -- Science. 2015 Jan 9;347(6218):188-94. doi: 10.1126/science.1257132. Epub 2015 Jan 7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Department of Biology, 9 Cambridge Center, Cambridge, MA 02142, USA. Howard Hughes Medical Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Koch Institute for Integrative Cancer Research, 77 Massachusetts Avenue, Cambridge, MA 02139, USA. Broad Institute of Harvard and Massachusetts Institute of Technology, 7 Cambridge Center, Cambridge, MA 02142, USA. ; Harvard Medical School, 260 Longwood Avenue, Boston, MA 02115, USA. ; Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA. ; Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Department of Biology, 9 Cambridge Center, Cambridge, MA 02142, USA. Howard Hughes Medical Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Koch Institute for Integrative Cancer Research, 77 Massachusetts Avenue, Cambridge, MA 02139, USA. Broad Institute of Harvard and Massachusetts Institute of Technology, 7 Cambridge Center, Cambridge, MA 02142, USA. sabatini@wi.mit.edu.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25567906" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Amino Acid Transport Systems/chemistry/genetics/*metabolism ; Arginine/deficiency/*metabolism ; HEK293 Cells ; Humans ; Lysosomes/*enzymology ; Molecular Sequence Data ; Monomeric GTP-Binding Proteins/*metabolism ; Multiprotein Complexes/*metabolism ; Protein Structure, Tertiary ; Signal Transduction ; TOR Serine-Threonine Kinases/*metabolism
    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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  • 7
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 41 (1995), S. 1413-1425 
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The adsorption of ethane from helium was measured in beds packed with 2.5 μm zeolite crystals and containing either a single hollow fiber or multiple fibers. THe single-fiber experiments indicate that the mass-transfer rate in bends containing zeolite 13X is limited by diffusion across the fiber wall and through macropores. FOr adsorption in single-fiber beds packed with zeolite 4A, mass transfer is limited by micropore diffusion within the particles. Breakthrough curves from beds containign 13X are adequately described with the linear driving force model, while curves from beds containing 4A are consistent with the Rosen model.Breakthrough curves from beds packed with zeolite 13X and containing multiple fibers can be predicted from the experiments with single-fiber beds when the fibers are evenly spaced. When fibers are unevenly spaced, the breakthrough curves are more disperse. Unevenly spaced fibers are the normal case. Even when fibers are evenly spaced, the productivity of hollow-fiber beds is expected to be no greater than that in conventional beds.
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  • 8
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 43 (1997), S. 847-850 
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 3 Ill.
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  • 9
    ISSN: 0272-8397
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: An investigation into the effect of isothermal aging on the development of transverse cracks in cross-ply laminates of two high temperature composite systems was performed. The composite materials investigated were BASF X5260/640-800 and DuPont Avimid K/IM6. Changes in the glass transition temperature, composite weight loss, crack density, and mode I intralaminar fracture toughness were monitored during isothermal aging in air at 177°C for up to 2232 h. The two laminate configurations used in this study include two variations of the generic cross-ply configuration [02/90n]s, in which n equals 1 and 2. The results of this investigation show that a layer of degraded material forms at the surface of the X5260/640-800 bismaleimide laminates and that the thickness of the degraded layer increases with aging time. After 744 h of aging, transverse cracks form in the surface plies and an increasing crack density evolves as aging time is increased; however, transverse cracks do not form in the inner 90° ply groups with aging during the time period investigated. The Avimid K/IM6 thermoplastic polyimide laminates, which show evidence of cracking prior to aging, do not exhibit any significant change in crack density with aging. The results of the aging experiments also show that the bismaleimide system exhibits a weight loss of 1.5% and an increase in glass transition temperature from 250°C to 300°C after 2232 h of aging at 177°C, while the thermoplastic polyimide system shows a weight loss of only 0.05% and an increase in glass transition temperature from 280 to 285°C after 2232 h. Changes in the resistance to crack formation are also seen in these materials during aging. The mode I intralaminar fracture toughness, a measure of resistance to transverse crack formation, shows a 50% decrease after aging for 2232 h for the bismaleimide system, while the behavior exhibited by the thermoplastic polyimide shows little evidence of a reduction.
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  • 10
    Publication Date: 1998-10-23
    Description: Analysis of the 1,042,519-base pair Chlamydia trachomatis genome revealed unexpected features related to the complex biology of chlamydiae. Although chlamydiae lack many biosynthetic capabilities, they retain functions for performing key steps and interconversions of metabolites obtained from their mammalian host cells. Numerous potential virulence-associated proteins also were characterized. Several eukaryotic chromatin-associated domain proteins were identified, suggesting a eukaryotic-like mechanism for chlamydial nucleoid condensation and decondensation. The phylogenetic mosaic of chlamydial genes, including a large number of genes with phylogenetic origins from eukaryotes, implies a complex evolution for adaptation to obligate intracellular parasitism.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Stephens, R S -- Kalman, S -- Lammel, C -- Fan, J -- Marathe, R -- Aravind, L -- Mitchell, W -- Olinger, L -- Tatusov, R L -- Zhao, Q -- Koonin, E V -- Davis, R W -- AI 39258/AI/NIAID NIH HHS/ -- New York, N.Y. -- Science. 1998 Oct 23;282(5389):754-9.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Program in Infectious Diseases, University of California, Berkeley, CA 94720, USA. ctgenome@socrates.berkeley.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/9784136" target="_blank"〉PubMed〈/a〉
    Keywords: Aerobiosis ; Amino Acid Sequence ; Amino Acids/biosynthesis ; Bacterial Outer Membrane Proteins/genetics ; Bacterial Proteins/chemistry/genetics ; Biological Evolution ; Chlamydia trachomatis/classification/*genetics/metabolism/physiology ; DNA Repair ; Energy Metabolism ; Enzymes/chemistry/genetics ; *Genome, Bacterial ; Humans ; Lipids/biosynthesis ; Molecular Sequence Data ; Peptidoglycan/biosynthesis/genetics ; Phylogeny ; Protein Biosynthesis ; Recombination, Genetic ; *Sequence Analysis, DNA ; Transcription, Genetic ; Transformation, Bacterial ; Virulence
    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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