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  • 1
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    Role of BAX in the apoptotic response to anticancer agents (2000)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2000-11-04
    Description: To assess the role of BAX in drug-induced apoptosis in human colorectal cancer cells, we generated cells that lack functional BAX genes. Such cells were partially resistant to the apoptotic effects of the chemotherapeutic agent 5-fluorouracil, but apoptosis was not abolished. In contrast, the absence of BAX completely abolished the apoptotic response to the chemopreventive agent sulindac and other nonsteroidal anti-inflammatory drugs (NSAIDs). NSAIDs inhibited the expression of the antiapoptotic protein Bcl-XL, resulting in an altered ratio of BAX to Bcl-XL and subsequent mitochondria-mediated cell death. These results establish an unambiguous role for BAX in apoptotic processes in human epithelial cancers and may have implications for cancer chemoprevention strategies.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Zhang, L -- Yu, J -- Park, B H -- Kinzler, K W -- Vogelstein, B -- CA 43460/CA/NCI NIH HHS/ -- CA 57345/CA/NCI NIH HHS/ -- CA 62924/CA/NCI NIH HHS/ -- etc. -- New York, N.Y. -- Science. 2000 Nov 3;290(5493):989-92.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Howard Hughes Medical Institute, Oncology Center, and Program in Human Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/11062132" target="_blank"〉PubMed〈/a〉
    Keywords: Anti-Inflammatory Agents, Non-Steroidal/*pharmacology ; Anticarcinogenic Agents/pharmacology ; Antimetabolites, Antineoplastic/*pharmacology ; *Apoptosis ; Colorectal Neoplasms/genetics/metabolism/*pathology ; Fluorouracil/*pharmacology ; Genes, p53 ; Humans ; Indomethacin/pharmacology ; Intracellular Membranes/drug effects/physiology ; Membrane Potentials/drug effects ; Mitochondria/drug effects/physiology ; Mutation ; Proto-Oncogene Proteins/genetics/*metabolism ; Proto-Oncogene Proteins c-bcl-2/metabolism ; Proto-Oncogenes ; Sulindac/pharmacology ; Tumor Cells, Cultured ; Tumor Suppressor Protein p53/metabolism ; bcl-2-Associated X Protein ; bcl-X Protein
    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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  • 2
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    International network of cancer genome projects (2010)
    Nature Publishing Group (NPG)
    Details
    Publication Date: 2010-04-16
    Description: The International Cancer Genome Consortium (ICGC) was launched to coordinate large-scale cancer genome studies in tumours from 50 different cancer types and/or subtypes that are of clinical and societal importance across the globe. Systematic studies of more than 25,000 cancer genomes at the genomic, epigenomic and transcriptomic levels will reveal the repertoire of oncogenic mutations, uncover traces of the mutagenic influences, define clinically relevant subtypes for prognosis and therapeutic management, and enable the development of new cancer therapies.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2902243/" 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/PMC2902243/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉International Cancer Genome Consortium -- Hudson, Thomas J -- Anderson, Warwick -- Artez, Axel -- Barker, Anna D -- Bell, Cindy -- Bernabe, Rosa R -- Bhan, M K -- Calvo, Fabien -- Eerola, Iiro -- Gerhard, Daniela S -- Guttmacher, Alan -- Guyer, Mark -- Hemsley, Fiona M -- Jennings, Jennifer L -- Kerr, David -- Klatt, Peter -- Kolar, Patrik -- Kusada, Jun -- Lane, David P -- Laplace, Frank -- Youyong, Lu -- Nettekoven, Gerd -- Ozenberger, Brad -- Peterson, Jane -- Rao, T S -- Remacle, Jacques -- Schafer, Alan J -- Shibata, Tatsuhiro -- Stratton, Michael R -- Vockley, Joseph G -- Watanabe, Koichi -- Yang, Huanming -- Yuen, Matthew M F -- Knoppers, Bartha M -- Bobrow, Martin -- Cambon-Thomsen, Anne -- Dressler, Lynn G -- Dyke, Stephanie O M -- Joly, Yann -- Kato, Kazuto -- Kennedy, Karen L -- Nicolas, Pilar -- Parker, Michael J -- Rial-Sebbag, Emmanuelle -- Romeo-Casabona, Carlos M -- Shaw, Kenna M -- Wallace, Susan -- Wiesner, Georgia L -- Zeps, Nikolajs -- Lichter, Peter -- Biankin, Andrew V -- Chabannon, Christian -- Chin, Lynda -- Clement, Bruno -- de Alava, Enrique -- Degos, Francoise -- Ferguson, Martin L -- Geary, Peter -- Hayes, D Neil -- Johns, Amber L -- Kasprzyk, Arek -- Nakagawa, Hidewaki -- Penny, Robert -- Piris, Miguel A -- Sarin, Rajiv -- Scarpa, Aldo -- van de Vijver, Marc -- Futreal, P Andrew -- Aburatani, Hiroyuki -- Bayes, Monica -- Botwell, David D L -- Campbell, Peter J -- Estivill, Xavier -- Grimmond, Sean M -- Gut, Ivo -- Hirst, Martin -- Lopez-Otin, Carlos -- Majumder, Partha -- Marra, Marco -- McPherson, John D -- Ning, Zemin -- Puente, Xose S -- Ruan, Yijun -- Stunnenberg, Hendrik G -- Swerdlow, Harold -- Velculescu, Victor E -- Wilson, Richard K -- Xue, Hong H -- Yang, Liu -- Spellman, Paul T -- Bader, Gary D -- Boutros, Paul C -- Flicek, Paul -- Getz, Gad -- Guigo, Roderic -- Guo, Guangwu -- Haussler, David -- Heath, Simon -- Hubbard, Tim J -- Jiang, Tao -- Jones, Steven M -- Li, Qibin -- Lopez-Bigas, Nuria -- Luo, Ruibang -- Muthuswamy, Lakshmi -- Ouellette, B F Francis -- Pearson, John V -- Quesada, Victor -- Raphael, Benjamin J -- Sander, Chris -- Speed, Terence P -- Stein, Lincoln D -- Stuart, Joshua M -- Teague, Jon W -- Totoki, Yasushi -- Tsunoda, Tatsuhiko -- Valencia, Alfonso -- Wheeler, David A -- Wu, Honglong -- Zhao, Shancen -- Zhou, Guangyu -- Lathrop, Mark -- Thomas, Gilles -- Yoshida, Teruhiko -- Axton, Myles -- Gunter, Chris -- Miller, Linda J -- Zhang, Junjun -- Haider, Syed A -- Wang, Jianxin -- Yung, Christina K -- Cros, Anthony -- Liang, Yong -- Gnaneshan, Saravanamuttu -- Guberman, Jonathan -- Hsu, Jack -- Chalmers, Don R C -- Hasel, Karl W -- Kaan, Terry S H -- Lowrance, William W -- Masui, Tohru -- Rodriguez, Laura Lyman -- Vergely, Catherine -- Bowtell, David D L -- Cloonan, Nicole -- deFazio, Anna -- Eshleman, James R -- Etemadmoghadam, Dariush -- Gardiner, Brooke B -- Kench, James G -- Sutherland, Robert L -- Tempero, Margaret A -- Waddell, Nicola J -- Wilson, Peter J -- Gallinger, Steve -- Tsao, Ming-Sound -- Shaw, Patricia A -- Petersen, Gloria M -- Mukhopadhyay, Debabrata -- DePinho, Ronald A -- Thayer, Sarah -- Shazand, Kamran -- Beck, Timothy -- Sam, Michelle -- Timms, Lee -- Ballin, Vanessa -- Lu, Youyong -- Ji, Jiafu -- Zhang, Xiuqing -- Chen, Feng -- Hu, Xueda -- Yang, Qi -- Tian, Geng -- Zhang, Lianhai -- Xing, Xiaofang -- Li, Xianghong -- Zhu, Zhenggang -- Yu, Yingyan -- Yu, Jun -- Tost, Jorg -- Brennan, Paul -- Holcatova, Ivana -- Zaridze, David -- Brazma, Alvis -- Egevard, Lars -- Prokhortchouk, Egor -- Banks, Rosamonde Elizabeth -- Uhlen, Mathias -- Viksna, Juris -- Ponten, Fredrik -- Skryabin, Konstantin -- Birney, Ewan -- Borg, Ake -- Borresen-Dale, Anne-Lise -- Caldas, Carlos -- Foekens, John A -- Martin, Sancha -- Reis-Filho, Jorge S -- Richardson, Andrea L -- Sotiriou, Christos -- Thoms, Giles -- van't Veer, Laura -- Birnbaum, Daniel -- Blanche, Helene -- Boucher, Pascal -- Boyault, Sandrine -- Masson-Jacquemier, Jocelyne D -- Pauporte, Iris -- Pivot, Xavier -- Vincent-Salomon, Anne -- Tabone, Eric -- Theillet, Charles -- Treilleux, Isabelle -- Bioulac-Sage, Paulette -- Decaens, Thomas -- Franco, Dominique -- Gut, Marta -- Samuel, Didier -- Zucman-Rossi, Jessica -- Eils, Roland -- Brors, Benedikt -- Korbel, Jan O -- Korshunov, Andrey -- Landgraf, Pablo -- Lehrach, Hans -- Pfister, Stefan -- Radlwimmer, Bernhard -- Reifenberger, Guido -- Taylor, Michael D -- von Kalle, Christof -- Majumder, Partha P -- Pederzoli, Paolo -- Lawlor, Rita A -- Delledonne, Massimo -- Bardelli, Alberto -- Gress, Thomas -- Klimstra, David -- Zamboni, Giuseppe -- Nakamura, Yusuke -- Miyano, Satoru -- Fujimoto, Akihiro -- Campo, Elias -- de Sanjose, Silvia -- Montserrat, Emili -- Gonzalez-Diaz, Marcos -- Jares, Pedro -- Himmelbauer, Heinz -- Bea, Silvia -- Aparicio, Samuel -- Easton, Douglas F -- Collins, Francis S -- Compton, Carolyn C -- Lander, Eric S -- Burke, Wylie -- Green, Anthony R -- Hamilton, Stanley R -- Kallioniemi, Olli P -- Ley, Timothy J -- Liu, Edison T -- Wainwright, Brandon J -- 077198/Wellcome Trust/United Kingdom -- 088340/Wellcome Trust/United Kingdom -- 093867/Wellcome Trust/United Kingdom -- 6613/Cancer Research UK/United Kingdom -- K08 DK071329/DK/NIDDK NIH HHS/ -- K08 DK071329-04/DK/NIDDK NIH HHS/ -- K08 DK071329-05/DK/NIDDK NIH HHS/ -- P01 CA117969/CA/NCI NIH HHS/ -- P01 CA117969-04S1/CA/NCI NIH HHS/ -- P01 CA117969-05/CA/NCI NIH HHS/ -- P50 CA102701/CA/NCI NIH HHS/ -- P50 CA102701-08/CA/NCI NIH HHS/ -- P50 CA127003/CA/NCI NIH HHS/ -- P50 CA127003-04/CA/NCI NIH HHS/ -- P50 CA127003-05/CA/NCI NIH HHS/ -- R01 HG001806-02/HG/NHGRI NIH HHS/ -- England -- Nature. 2010 Apr 15;464(7291):993-8. doi: 10.1038/nature08987.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/20393554" target="_blank"〉PubMed〈/a〉
    Keywords: DNA Methylation ; DNA Mutational Analysis/trends ; Databases, Genetic ; Genes, Neoplasm/genetics ; Genetics, Medical/*organization & administration/trends ; Genome, Human/*genetics ; Genomics/*organization & administration/trends ; Humans ; Intellectual Property ; *International Cooperation ; Mutation ; Neoplasms/classification/*genetics/pathology/therapy
    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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  • 3
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    pH sensing by intracellular Salmonella induces effector translocation (2010)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2010-04-17
    Description: Salmonella enterica is an important intracellular bacterial pathogen of humans and animals. It replicates within host-cell vacuoles by delivering virulence (effector) proteins through a vacuolar membrane pore made by the Salmonella pathogenicity island 2 (SPI-2) type III secretion system (T3SS). T3SS assembly follows vacuole acidification, but when bacteria are grown at low pH, effector secretion is negligible. We found that effector secretion was activated at low pH from mutant strains lacking a complex of SPI-2-encoded proteins SsaM, SpiC, and SsaL. Exposure of wild-type bacteria to pH 7.2 after growth at pH 5.0 caused dissociation and degradation of SsaM/SpiC/SsaL complexes and effector secretion. In infected cells, loss of the pH 7.2 signal through acidification of host-cell cytosol prevented complex degradation and effector translocation. Thus, intravacuolar Salmonella senses host cytosolic pH, resulting in the degradation of regulatory complex proteins and effector translocation.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Yu, Xiu-Jun -- McGourty, Kieran -- Liu, Mei -- Unsworth, Kate E -- Holden, David W -- 074553/Z/04/Z/Wellcome Trust/United Kingdom -- G0800148/Medical Research Council/United Kingdom -- New York, N.Y. -- Science. 2010 May 21;328(5981):1040-3. doi: 10.1126/science.1189000. Epub 2010 Apr 15.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Section of Microbiology, Centre for Molecular Microbiology and Infection, Imperial College London, Armstrong Road, London SW7 2AZ, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/20395475" target="_blank"〉PubMed〈/a〉
    Keywords: Bacterial Processes ; Bacterial Proteins/chemistry/genetics/*metabolism ; Cytosol/chemistry ; Genomic Islands ; HeLa Cells ; Humans ; Hydrogen-Ion Concentration ; Molecular Chaperones/metabolism ; Multiprotein Complexes/metabolism ; Mutation ; Salmonella typhimurium/genetics/growth & development/*metabolism/pathogenicity ; Vacuoles/metabolism/*microbiology ; Virulence Factors/*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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  • 4
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    Structural basis of type II topoisomerase inhibition by the anticancer drug etoposide (2011)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2011-07-23
    Description: Type II topoisomerases (TOP2s) resolve the topological problems of DNA by transiently cleaving both strands of a DNA duplex to form a cleavage complex through which another DNA segment can be transported. Several widely prescribed anticancer drugs increase the population of TOP2 cleavage complex, which leads to TOP2-mediated chromosome DNA breakage and death of cancer cells. We present the crystal structure of a large fragment of human TOP2beta complexed to DNA and to the anticancer drug etoposide to reveal structural details of drug-induced stabilization of a cleavage complex. The interplay between the protein, the DNA, and the drug explains the structure-activity relations of etoposide derivatives and the molecular basis of drug-resistant mutations. The analysis of protein-drug interactions provides information applicable for developing an isoform-specific TOP2-targeting strategy.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Wu, Chyuan-Chuan -- Li, Tsai-Kun -- Farh, Lynn -- Lin, Li-Ying -- Lin, Te-Sheng -- Yu, Yu-Jen -- Yen, Tien-Jui -- Chiang, Chia-Wang -- Chan, Nei-Li -- New York, N.Y. -- Science. 2011 Jul 22;333(6041):459-62. doi: 10.1126/science.1204117.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei City 100, Taiwan.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21778401" target="_blank"〉PubMed〈/a〉
    Keywords: Base Pairing ; Catalytic Domain ; Crystallography, X-Ray ; DNA/*chemistry/metabolism ; DNA Topoisomerases, Type II/*chemistry/genetics/metabolism ; DNA-Binding Proteins/*chemistry/genetics/metabolism ; Drug Resistance, Neoplasm ; Etoposide/analogs & derivatives/*chemistry/metabolism/*pharmacology ; Humans ; Models, Molecular ; Mutant Proteins/chemistry/metabolism ; Mutation ; Protein Multimerization ; Protein Structure, Quaternary ; Protein Structure, Tertiary ; Structure-Activity Relationship ; Topoisomerase II Inhibitors/*chemistry/metabolism/*pharmacology
    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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    Enhanced fitness conferred by naturally occurring variation in the circadian clock (2003)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2003-11-08
    Description: Natural variation in clock parameters is necessary for the circadian clock to contribute to organismal fitness over a broad geographic range. Considerable variation is evident in the period, phase, and amplitude of 150 Arabidopsis accessions, and the period length is correlated with the day length at the latitude of origin, implying the adaptive significance of correctly regulated circadian timing. Quantitative trait loci analysis of recombinant inbred lines indicates that multiple loci interact to determine period, phase, and amplitude. The loss-of-function analysis of each member of the ARABIDOPSIS PSEUDO-RESPONSE REGULATOR family suggests that they are candidates for clock quantitative trait loci.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Michael, Todd P -- Salome, Patrice A -- Yu, Hannah J -- Spencer, Taylor R -- Sharp, Emily L -- McPeek, Mark A -- Alonso, Jose M -- Ecker, Joseph R -- McClung, C Robertson -- New York, N.Y. -- Science. 2003 Nov 7;302(5647):1049-53.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Dartmouth College, Department of Biological Sciences, Hanover, NH 03755, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/14605371" target="_blank"〉PubMed〈/a〉
    Keywords: Adaptation, Physiological ; Alleles ; Arabidopsis/genetics/*physiology ; Arabidopsis Proteins/genetics/*physiology ; Biological Clocks ; *Circadian Rhythm ; DNA, Bacterial ; Fourier Analysis ; *Genes, Plant ; *Genetic Variation ; Light ; Mutation ; Plant Leaves/*physiology ; *Quantitative Trait Loci ; Seasons ; Selection, Genetic ; Transcription Factors
    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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    Lightweight Ceramics for Aeroacoustic Applications (1997)
    In:  CASI
    Details
    Publication Date: 2019-06-28
    Description: The use of a HTP (High Temperature Performance) ceramic foam for aeroacoustic applications is investigated. HTP ceramic foam is a composition of silica and alumina fibers developed by LMMS. This foam is a lightweight high-temperature fibrous bulk material with small pore size, ultra high porosity, and good strength. It can be used as a broadband noise absorber at both room and high temperature (up to 1800 F). The investigation included an acoustic assessment as well as material development, and environmental and structural evaluations. The results show that the HTP ceramic foam provides good broadband noise absorbing capability and adequate strength when incorporating the HTP ceramic foam system into a honeycomb sandwich structure. On the other hand, the material is sensitive to Skydrol and requires further improvements. Good progress has been made in the impedance model development. A relationship between HTP foam density, flow resistance, and tortuosity will be established in the near future. Additional effort is needed to investigate the coupling effects between face sheet and HTP foam material.
    Keywords: Acoustics
    Type: NASA-CR-201709 , NAS 1.26:201709
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  • 7
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    Advanced Nacelle Acoustic Lining Concepts Development (2002)
    In:  CASI
    Details
    Publication Date: 2019-07-10
    Description: The work reported in this document consisted of six distinct liner technology development subtasks: 1) Analysis of Model Scale ADP Fan Duct Lining Data (Boeing): An evaluation of an AST Milestone experiment to demonstrate 1995 liner technology superiority relative to that of 1992 was performed on 1:5.9 scale model fan rig (Advanced Ducted Propeller) test data acquired in the NASA Glenn 9 x 15 foot wind tunnel. The goal of 50% improvement was deemed satisfied. 2) Bias Flow Liner Investigation (Boeing, VCES): The ability to control liner impedance by low velocity bias flow through liner was demonstrated. An impedance prediction model to include bias flow was developed. 3) Grazing Flow Impedance Testing (Boeing): Grazing flow impedance tests were conducted for comparison with results achieved at four different laboratories. 4) Micro-Perforate Acoustic Liner Technology (BFG, HAE, NG): Proof of concept testing of a "linear liner." 5) Extended Reaction Liners (Boeing, NG): Bandwidth improvements for non-locally reacting liner were investigated with porous honeycomb core test liners. 6) Development of a Hybrid Active/Passive Lining Concept (HAE): Synergism between active and passive attenuation of noise radiated by a model inlet was demonstrated.
    Keywords: Acoustics
    Type: NASA/CR-2002-211672 , NAS 1.26:211672
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  • 8
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    Acoustic Treatment Design Scaling Methods (2003)
    In:  CASI
    Details
    Publication Date: 2019-07-13
    Description: The ability to design, build and test miniaturized acoustic treatment panels on scale model fan rigs representative of full scale engines provides not only cost-savings, but also an opportunity to optimize the treatment by allowing multiple tests. To use scale model treatment as a design tool, the impedance of the sub-scale liner must be known with confidence. This study was aimed at developing impedance measurement methods for high frequencies. A normal incidence impedance tube method that extends the upper frequency range to 25,000 Hz. without grazing flow effects was evaluated. The free field method was investigated as a potential high frequency technique. The potential of the two-microphone in-situ impedance measurement method was evaluated in the presence of grazing flow. Difficulties in achieving the high frequency goals were encountered in all methods. Results of developing a time-domain finite difference resonator impedance model indicated that a re-interpretation of the empirical fluid mechanical models used in the frequency domain model for nonlinear resistance and mass reactance may be required. A scale model treatment design that could be tested on the Universal Propulsion Simulator vehicle was proposed.
    Keywords: Acoustics
    Type: NASA/CR-2003-212428/PHASE2 , NAS 1.26:212428/PHASE2
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  • 9
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    Acoustic Treatment Design Scaling Methods (1999)
    In:  CASI
    Details
    Publication Date: 2019-07-10
    Description: Scale model fan rigs that simulate new generation ultra-high-bypass engines at about 1/5-scale are achieving increased importance as development vehicles for the design of low-noise aircraft engines. Testing at small scale allows the tests to be performed in existing anechoic wind tunnels, which provides an accurate simulation of the important effects of aircraft forward motion on the noise generation. The ability to design, build, and test miniaturized acoustic treatment panels on scale model fan rigs representative of the fullscale engine provides not only a cost-savings, but an opportunity to optimize the treatment by allowing tests of different designs. The primary objective of this study was to develop methods that will allow scale model fan rigs to be successfully used as acoustic treatment design tools. The study focuses on finding methods to extend the upper limit of the frequency range of impedance prediction models and acoustic impedance measurement methods for subscale treatment liner designs, and confirm the predictions by correlation with measured data. This phase of the program had as a goal doubling the upper limit of impedance measurement from 6 kHz to 12 kHz. The program utilizes combined analytical and experimental methods to achieve the objectives.
    Keywords: Acoustics
    Type: NASA/CR-1999-209120/VOL1 , NAS 1.26:209120/VOL1
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  • 10
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    Acoustic Treatment Design Scaling Methods (1999)
    In:  CASI
    Details
    Publication Date: 2019-07-10
    Description: The ability to design, build, and test miniaturized acoustic treatment panels on scale-model fan rigs representative of the full-scale engine provides not only a cost-savings, but an opportunity to optimize the treatment by allowing tests of different designs. To be able to use scale model treatment as a full-scale design tool, it is necessary that the designer be able to reliably translate the scale model design and performance to an equivalent full-scale design. The primary objective of the study presented in this volume of the final report was to conduct laboratory tests to evaluate liner acoustic properties and validate advanced treatment impedance models. These laboratory tests include DC flow resistance measurements, normal incidence impedance measurements, DC flow and impedance measurements in the presence of grazing flow, and in-duct liner attenuation as well as modal measurements. Test panels were fabricated at three different scale factors (i.e., full-scale, half-scale, and one-fifth scale) to support laboratory acoustic testing. The panel configurations include single-degree-of-freedom (SDOF) perforated sandwich panels, SDOF linear (wire mesh) liners, and double-degree-of-freedom (DDOF) linear acoustic panels.
    Keywords: Acoustics
    Type: NASA/CR-1999-209120/VOL3 , NAS 1.26:209120/VOL3
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