Bibliografie tematiche / Blages

Indice

  1. Articoli di riviste
  2. Tesi
  3. Libri
  4. Capitoli di libri
  5. Atti di convegni
  6. Rapporti di organizzazioni

Letteratura scientifica selezionata sul tema "Blages"

Autore: Grafiati
Pubblicato: 4 giugno 2021
Ultima modifica: 1 febbraio 2022

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili

Scegli il tipo di fonte:

Consulta la lista di attuali articoli, libri, tesi, atti di convegni e altre fonti scientifiche attinenti al tema "Blages".

Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.

Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.

Articoli di riviste sul tema "Blages"

1

Fonseca, Érica L., e Ana Carolina Paulo Vicente. "Polycistronic transcription of fused cassettes and identification of translation initiation signals in an unusual gene cassette array from Pseudomonas aeruginosa". F1000Research 2 (28 marzo 2013): 99. http://dx.doi.org/10.12688/f1000research.2-99.v1.

Testo completo
Abstract (sommario):
The gene cassettes found in class 1 integrons are generally promoterless units composed by an open reading frame (ORF), a short 5’ untranslated region (UTR) and a 3’ recombination site (attC). Fused gene cassettes are generated by partial or total loss of the attC from the first cassette in an array, creating a fusion with the ORF from the next cassette. These structures are rare and little is known about their mechanisms of mobilization and expression. The aim of this study was to evaluate the dynamic of mobilization and transcription of the gcu14-blaGES-1/aacA4 gene cassette array, which harbours a fused gene cassette represented by blaGES-1/aacA4. The cassette array was analyzed by Northern blot and real-time reverse transcription-polymerase chain reaction (RT-PCR) in order to assess the transcription mechanism of blaGES-1/aacA4 fused cassette. Also, inverse polymerase chain reactions (PCR) were performed to detect the free circular forms of gcu14, blaGES-1 and aacA4. The Northern blot and real time RT-PCR revealed a polycistronic transcription, in which the fused cassette blaGES-1/aacA4 is transcribed as a unique gene, while gcu14 (with a canonical attC recombination site) has a monocistronic transcription. The gcu14 cassette, closer to the weak configuration of cassette promoter (Pc), had a higher transcription level than blaGES-1/aacA4, indicating that the cassette position impacts the transcript amounts. The presence of ORF-11 at attI1, immediately preceding gcu14, and of a Shine-Dalgarno sequence upstream blaGES-1/aacA4 composes a scenario for the occurrence of array translation. Inverse PCR generated amplicons corresponding to gcu14, gcu14-aacA4 and gcu14-blaGES-1/aacA4 free circular forms, but not to blaGES-1 and aacA4 alone, indicating that the GES-1 truncated attC is not substrate of integrase activity and that these genes are mobilized together as a unique cassette. This study was original in showing the transcription of fused cassettes and in correlating cassette position with transcription.
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Fonseca, Érica L., e Ana Carolina Paulo Vicente. "Polycistronic transcription of fused cassettes and identification of translation initiation signals in an unusual gene cassette array from Pseudomonas aeruginosa". F1000Research 2 (7 settembre 2015): 99. http://dx.doi.org/10.12688/f1000research.2-99.v2.

Testo completo
Abstract (sommario):
The gene cassettes found in class 1 integrons are generally promoterless units composed by an open reading frame (ORF), a short 5’ untranslated region (UTR) and a 3’ recombination site (attC). Fused gene cassettes are generated by partial or total loss of the attC from the first cassette in an array, creating, in some cases, a fusion with the ORF from the next cassette. These structures are rare and little is known about their mechanisms of mobilization and expression. The aim of this study was to evaluate the dynamic of mobilization and transcription of the gcu14-blaGES-1/aacA4 gene cassette array, which harbours a fused gene cassette represented by blaGES-1/aacA4. The cassette array was analyzed by Northern blot and real-time reverse transcription-polymerase chain reaction (RT-PCR) in order to assess the transcription mechanism of blaGES-1/aacA4 fused cassette. Also, inverse polymerase chain reactions (PCR) were performed to detect the free circular forms of gcu14, blaGES-1 and aacA4. The Northern blot and real time RT-PCR revealed a polycistronic transcription, in which the fused cassette blaGES-1/aacA4 is transcribed as a unique gene, while gcu14 (with a canonical attC recombination site) has a monocistronic transcription. The gcu14 cassette, closer to the weak configuration of cassette promoter (PcW), had a higher transcription level than blaGES-1/aacA4, indicating that the cassette position affects the transcript amounts. The presence of ORF-11 at attI1, immediately preceding gcu14, and of a Shine-Dalgarno sequence upstream blaGES-1/aacA4 composes a scenario for the occurrence of array translation. Inverse PCR generated amplicons corresponding to gcu14, gcu14-aacA4 and gcu14-blaGES-1/aacA4 free circular forms, but not to blaGES-1 and aacA4 alone, indicating that the GES-1 truncated attC is not substrate of integrase activity and that these genes are mobilized together as a unique cassette. This study was original in showing the transcription of fused cassettes and in correlating cassette position with transcription.
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Fonseca, Érica L., e Ana Carolina Paulo Vicente. "Polycistronic transcription of fused cassettes and identification of translation initiation signals in an unusual gene cassette array from Pseudomonas aeruginosa". F1000Research 2 (27 novembre 2015): 99. http://dx.doi.org/10.12688/f1000research.2-99.v3.

Testo completo
Abstract (sommario):
The gene cassettes found in class 1 integrons are generally promoterless units composed by an open reading frame (ORF), a short 5’ untranslated region (UTR) and a 3’ recombination site (attC). Fused gene cassettes are generated by partial or total loss of the attC from the first cassette in an array, creating, in some cases, a fusion with the ORF from the next cassette. These structures are rare and little is known about their mechanisms of mobilization and expression. The aim of this study was to evaluate the dynamic of mobilization and transcription of the gcu14-blaGES-1/aacA4 gene cassette array, which harbours a fused gene cassette represented by blaGES-1/aacA4. The cassette array was analyzed by Northern blot and real-time reverse transcription-polymerase chain reaction (RT-PCR) in order to assess the transcription mechanism of blaGES-1/aacA4 fused cassette. Also, inverse polymerase chain reactions (PCR) were performed to detect the free circular forms of gcu14, blaGES-1 and aacA4. The Northern blot and real time RT-PCR revealed a polycistronic transcription, in which the fused cassette blaGES-1/aacA4 is transcribed as a unique gene, while gcu14 (with a canonical attC recombination site) has a monocistronic transcription. The gcu14 cassette, closer to the weak configuration of cassette promoter (PcW), had a higher transcription level than blaGES-1/aacA4, indicating that the cassette position affects the transcript amounts. The presence of ORF-11 at attI1, immediately preceding gcu14, and of a Shine-Dalgarno sequence upstream blaGES-1/aacA4 composes a scenario for the occurrence of array translation. Inverse PCR generated amplicons corresponding to gcu14, gcu14-aacA4 and gcu14-blaGES-1/aacA4 free circular forms, but not to blaGES-1 and aacA4 alone, indicating that the GES-1 truncated attC is not substrate of integrase activity and that these genes are mobilized together as a unique cassette. This study was original in showing the transcription of fused cassettes and in correlating cassette position with transcription.
Gli stili APA, Harvard, Vancouver, ISO e altri
4

Soares, Cynthia Regina Pedrosa, Felipe Rogerio Ferreira da Silva, Jorge Belém Oliveira Júnior, Paulo Sérgio Ramos de Araújo e Elza Ferreira Firmo. "Epidemiologia molecular de bacilos Gram-negativos multidroga resistente produtores de carbapenemases isoladas de diferentes sítios de infecção". Research, Society and Development 10, n. 9 (26 luglio 2021): e30210918070. http://dx.doi.org/10.33448/rsd-v10i9.18070.

Testo completo
Abstract (sommario):
A resistência a carbapenemases em bacilos gram-negativas (BGN) tornou-se um problema mundial, elevando a taxa de morbidade e mortalidade. O método automatizado foi utilizado para identificação e suscetibilidade dos isolados. E o método molecular foi aplicado na detecção de bacilos gram-negativas (BGN) produtoras de carbapenemase. Um total de 205 BGN foram recuperados a partir de diferentes amostras clínicas, resistentes a carbapenemases. Os genes de resistência blaKPC (57,5%), blaVIM (30,2%), blaGES (17%), blaNDM (15%) e blaSPM (2,4%) foram recuperados a partir de isolados clínicos. O gene blaIMP não foi detectado em nenhum dos isolados. É preocupante que Pseudomonas aeruginosa e Acinetobacter baumannii representem a maioria dos isolados (61,6%) recuperados de infecções de diferentes sítios, com alta resistência a carbapenêmicos, carregando simultaneamente os genes blaKPC, blaGES e blaVIM, assim como encontrados também em Enterobactericeae. A carbapenemase mais prevalente foi blaKPC e blaVIM, seguida de blaNDM dentre os isolados multidroga resistentes. Esses resultados são um ameaça à saúde pública, configurando altas taxas de resistência, limitando as opções terapêuticas.
Gli stili APA, Harvard, Vancouver, ISO e altri
5

de Araujo, Carlos Felipe Machado, Dalton Marcondes Silva, Marcos Tavares Carneiro, Sthefanie Ribeiro, Marcela Fontana-Maurell, Patricia Alvarez, Marise Dutra Asensi, Viviane Zahner e Ana Paula D'Alincourt Carvalho-Assef. "Detection of Carbapenemase Genes in Aquatic Environments in Rio de Janeiro, Brazil". Antimicrobial Agents and Chemotherapy 60, n. 7 (2 maggio 2016): 4380–83. http://dx.doi.org/10.1128/aac.02753-15.

Testo completo
Abstract (sommario):
ABSTRACTThis study reveals the presence of different carbapenemase genes (blaKPC,blaNDM,blaGES, andblaOXA48-likegenes) detected directly from water samples and clonal dispersion (by pulsed-field gel electrophoresis [PFGE] and multilocus sequence typing [MLST]) of KPC-2-producingEnterobacteriaceaein two important urban aquatic matrixes from Rio de Janeiro, Brazil, highlighting the role of aquatic environments as gene pools and the possibility of community spreading.
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Chen, Ding-Qiang, Ai-Wu Wu, Ling Yang, Dan-Hong Su, Yong-ping Lin, Yan-Wei Hu, Lei Zheng e Qian Wang. "Emergence and Plasmid Analysis of Klebsiella pneumoniae KP01 CarryingblaGES-5from Guangzhou, China". Antimicrobial Agents and Chemotherapy 60, n. 10 (18 luglio 2016): 6362–64. http://dx.doi.org/10.1128/aac.00764-16.

Testo completo
Abstract (sommario):
ABSTRACTKlebsiella pneumoniaestrain KP01 carryingblaGES-5was identified from a patient in Guangzhou, China. High-throughput sequencing assignedblaGES-5to a 28.5-kb nonconjugative plasmid, pGES-GZ. A 13-kb plasmid backbone sequence on pGES-GZ was found to share high sequence identities with plasmids from Gram-negative nonfermenters. A novel class 1 integron carrying a gene cassette array oforf28-orf28-blaGES-5was identified on pGES-GZ, within whichorf28encoded a hypothetical protein possibly correlated to fosfomycin resistance.
Gli stili APA, Harvard, Vancouver, ISO e altri
7

Manageiro, Vera, Eugénia Ferreira, Joana Almeida, Stephanie Barbosa, Constança Simões, Robert A. Bonomo e Manuela Caniça. "Predominance of KPC-3 in a Survey for Carbapenemase-Producing Enterobacteriaceae in Portugal". Antimicrobial Agents and Chemotherapy 59, n. 6 (16 marzo 2015): 3588–92. http://dx.doi.org/10.1128/aac.05065-14.

Testo completo
Abstract (sommario):
ABSTRACTAmong the 2,105Enterobacteriaceaetested in a survey done in Portugal, 165 were nonsusceptible to carbapenems, from which 35 (26Klebsiella pneumoniae, 3Escherichia coli, 2Enterobacter aerogenes, and 3Enterobacter cloacaeisolates and 1Klebsiella oxytocaisolate) were confirmed to be carbapenemase producers by the presence of 30Tn4401d-blaKPC-3, 4intI3-blaGES-5, and oneintI1-blaVIM-2gene, alone or in combination with otherblagenes. The dissemination ofblaKPC-3gene carried by an IncF plasmid suggests lateral gene transfer as a major mechanism of dissemination.
Gli stili APA, Harvard, Vancouver, ISO e altri
8

Leite, Belize, Magda Antunes de Chaves, Athos Aramis Thopor Nunes, Louise Jank e Gertrudes Corção. "Antibiotic resistance in surface waters from a coastal lagoon of Southern Brazil under the impact of anthropogenic activities". Ambiente e Agua - An Interdisciplinary Journal of Applied Science 14, n. 5 (24 settembre 2019): 1. http://dx.doi.org/10.4136/ambi-agua.2379.

Testo completo
Abstract (sommario):
Wastes arising from human activities can reach water bodies and contribute significantly to the presence of antibiotic resistant bacterial populations in aquatic environments. The objective of this study was to evaluate the cultivable antibiotic resistant bacterial populations from a coastal lagoon impacted by agriculture and urbanization activities. Water samples were collected in low and peak season and characterized regarding physicochemical variables, microbiological indicators and the presence of antimicrobial residues. In order to analyze the presence of resistant bacterial populations, the samples were grown in the presence of nalidixic acid, ceftazidime, imipenem and tetracycline. Genes associated with β-lactamic resistance (blaCTX-M-like, blaGES-like, blaOXA-51, blaOXA-23-like, blaSHV-like, blaTEM-like and blaSPM-1), class I integron and efflux systems (tetA, tetB, acrA, acrB, tolC, adeA, adeB, adeR, adeS, mexB, mexD, mexF and mexY) were analyzed by conventional in vitro amplification. Although antimicrobials residues were below the detection limit, resistant bacteria and resistance determinants - blaGES, class I integron, adeS, acrA, acrB, tolC, mexB, mexF - were present at almost all points, in both seasons and for all antimicrobials assessed. The high numbers of resistant bacteria counts observed after the antibiotic treatment were positively correlated to the urbanization effects on the Lagoon. Some resistant populations were even higher in the low season samples, indicating the importance of a systematic evaluation of antibiotic resistance on water resources.
Gli stili APA, Harvard, Vancouver, ISO e altri
9

Cilveti, Camila, Miryan Rivera, Mercedes Rodríguez Riglos e Iliana Alcocer. "Inhibición de enterobacterias portadoras de carbapenemasas con secreciones peptídicas de anfibios nativos ecuatorianos." Revista Ecuatoriana de Medicina y Ciencias Biológicas 34, n. 1-2 (14 agosto 2017): 85–98. http://dx.doi.org/10.26807/remcb.v34i1-2.237.

Testo completo
Abstract (sommario):
La resistencia bacteriana representa un problema para la salud pública, especialmente la producida por enzimas llamadas betalactamasas, que bloquean a un grupo importante de antibióticos, los betalactámicos, utilizados ampliamente para el tratamiento de infecciones en seres humanos. Las enterobacterias productoras de betalactamasas de espectro extendido (BLEEs) son las más preocupantes, pues son un grupo importante dentro de la etiología de las infecciones tanto severas como no severas. Los carbapenemes son antibióticos betalactámicos para el tratamiento de infecciones causadas por enterobacterias BLEE, que están resultando ineficientes por el aparecimiento de cepas resistentes a estos antibióticos. Ante la escasez de otras opciones terapéuticas, el presente estudio tuvo como objetivo caracterizar molecularmente carbapenemasas en enterobacterias y analizar su posible inhibición con secreciones peptídicas de un bufónido nativo ecuatoriano. Se caracterizaron 57 enterobacterias resistentes a carbapenemes de pacientes hospitalizados. Esta población fue caracterizada molecularmente, encontrándose los genes blaKPC, blaGES, blaVIM y blaIMP. Los genes con mayor prevalencia fueron blaKPC y blaGES, seguidos por blaVIM y blaIMP. Todos los aislados fueron inhibidos por el péptido. La concentración inhibitoria mínima fue 250 μg/ml para Klebsiella pneumoniae, Serratia marcescens, Enterobacter aerogenes y E. cloacae, 125 μg/ml para Morganella morganii, 62.5 μg/ml para Klebsiella oxytoca y Serratia rubidaea y 31.3 μg/ml para Escherichia coli. La presencia de genes para betalactamasas en elementos móviles facilita su propagación. Por esta razón la importancia de analizar nuevos compuestos antimicrobianos.
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Pellegrino, Flávia L. P. C., Kátia R. Netto-dos Santos, Lee W. Riley e Beatriz M. Moreira. "blaGES carrying Pseudomonas aeruginosa isolates from a public hospital in Rio de Janeiro, Brazil". Brazilian Journal of Infectious Diseases 10, n. 4 (agosto 2006): 251–53. http://dx.doi.org/10.1590/s1413-86702006000400007.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Più fonti

Tesi sul tema "Blages"

1

Weldhagen, Gerhard Frederick. "Laboratory Detection and Gene Cassette Stability of the Novel Extended-Spectrum Beta-Lactamase, GES-2 from Pseudomonas aeruginosa". Thesis, University of Pretoria, 2004. http://hdl.handle.net/2263/29221.

Testo completo
Abstract (sommario):
Extended-spectrum beta-lactamases (ESBLs) in Pseudomonas aeruginosa tend to be geographically scattered, such as GES-2, which partially compromises the efficacy of imipenem. The G170N mutation, ascribed to a CC to AA base pair substitution on positions 493-494 of the blaGES-2 coding region, distinguishes this ESBL from blaGES-1 and the blaIBC-type genes, making it an ideal target for developing a novel sequence-specific, peptide nucleic acid (PNA)-based, multiplex-PCR detection method. Utilizing two primer pairs in conjunction with a PNA probe, this novel method delivered accurate identification of blaGES-2 compared to standard PCR and gene sequencing techniques, when tested against one hundred (n = 100) P. aeruginosa clinical isolates as well as previously published, well-described control strains. This method has the potential to be used in large-scale, cost-effective screening programmes for specific or geographically restricted ESBLs. To date, in addition to being only described in South Africa, GES-2 is notoriously difficult to identify in P. aeruginosa, using standard methodology. A real-time PCR method using the LightCycler™ was compared to a two-step nested-PCR assay for the detection of blaGES and blaIBC genes from one hundred P. aeruginosa clinical isolates collected over a four-year period from two teaching hospitals in Pretoria, South Africa. Real-time PCR amplification was monitored through hybridisation of fluorescently labelled probes followed by melting curve analysis to detect the relevant G170N mutation occurring in the omega loop region of blaGES-2. Nested-PCR products were subjected to automated DNA sequencing and compared to melting point (Tm) analyses results obtained from the LightCycler assay. Real time and nested-PCR assays detected a blaIBC gene product from 83 and 88 clinical isolates respectively, with the LightCycler thus exhibiting a sensitivity of 94.3% compared to the nested-PCR assay. Comparison of Tm and gene sequencing data however revealed 100% specificity for sequence specific detection of blaGES-2 with the LightCycler. One clinical isolate was found to harbour a blaGES-1 gene, making this the first report of this specific ESBL from South Africa. Selective antibiotic pressure has recently been implicated as a possible driving force behind point mutations observed in blaGES–type genes. This part of the study subjected two well-characterized clinical isolates with class 1 integron-borne blaGES-type genes to five days incubation in the presence of sub-inhibitory concentrations of 15 different antibiotics, including beta-lactams, aminoglycosides and quinolones. Restriction enzyme analysis and DNA sequencing of blaGES-1, blaGES-2 and their immediate upstream genetic environments failed to demonstrate any changes compared to non-exposed controls. Short-term exposure to a sub-inhibitory level of a single antimicrobial agent is thus unlikely to select significant mutations in these beta-lactamase genes or their regulatory mechanisms.
Thesis (PhD (Medical Microbiology))--University of Pretoria, 2006.
Medical Microbiology
unrestricted
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Ruiz, Leonardo Guizilini Plazas [UNESP]. "Resistência aos beta-lactâmicos e detecção dos genes blashv, blatem, blactx-m e blages em Enterobacteriaceae isoladas de efluentes hospitar e comunitário em um município do noroeste paulista". Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/94851.

Testo completo
Abstract (sommario):
Made available in DSpace on 2014-06-11T19:27:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-10-26Bitstream added on 2014-06-13T20:35:44Z : No. of bitstreams: 1 ruiz_lgp_me_sjrp.pdf: 1611382 bytes, checksum: e9dd037c5c8d3c485f14ae8a1628ab2e (MD5)
As Enterobacteriaceae constituem um importante grupo de patógenos humanos, causadores de infecções hospitalares e comunitárias. Nestas bactérias, a produção de beta-lactamases de espectro estendido (ESBL) é um dos principais mecanismos de resistência aos antibióticos, e responsável pela falha da terapia antimicrobiana. Enterobactérias resistentes a antibióticos são encontradas em águas superficiais e apresentam alta prevalência em águas servidas, inclusive pós-tratamento. Esta realidade caracteriza-se como um importante problema de saúde pública, pois estes ambientes atuam como reservatórios de patógenos humanos e de genes de resistência que se disseminam horizontalmente. Crescentes evidências mostram a relação entre a disseminação ambiental de bactérias resistentes e genes de resistência e a evolução da resistência em bactérias de importância clínica. Este estudo investigou a diversidade de enterobactérias produtoras de ESBL e a presença dos genes blaSHV, blaTEM, blaCTX-M e blaGES em amostras de água coletadas de efluentes hospitalar e comunitário em um município localizado na região noroeste do estado de São Paulo. Genes de resistência foram detectados em várias espécies de Enterobacteriaceae apresentando resistência a diversas classes de antimicrobianos. Estes dados indicam a necessidade de adoção de medidas para o controle da disseminação de bactérias resistentes a antimicrobianos e seus genes no meio ambiente.
The Enterobacteriaceae constitutes an important group of human patogens, causing of hospital and communitarian infections. In these bacteria, the production of extended spectrum beta-lactamases (ESBL) is one of the main mechanisms of resistance the antibiotics, responsible for the imperfection of the therapy against infections for gram-negative bacilli. Enterobacteria resistant the antibiotics are found in superficial waters and present high prevalence in served waters, also post-cure. This reality is characterized as an important problem of public health, therefore these environments act as reservoirs of human patogens and genes of resistance that if spread through horizontal transmission. Increasing evidences show the relation between the ambient dissemination of resistant bacteria and genes of resistance and the evolution of the resistance in bacteria of clinical importance. This study it investigated the diversity of producing Enterobacteria of ESBL and the presence of the genes blaSHV, blaTEM, blaCTX-M and blaGES in water samples collected in the system of sewers in a city located in the region the northwest of the state of São Paulo. The respective genes of resistance had been detected in several strains producing of ESBL presenting profile of multiple resistant to the diverse antimicrobials groups, suggesting the necessity of the surveillance and the adoption of measures for the control of the dissemination of the genes of resistance in the environment.
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Ruiz, Leonardo Guizilini Plazas. ""Resistência aos beta-lactâmicos e detecção dos genes blashv, blatem, blactx-m e blages em Enterobacteriaceae isoladas de efluentes hospitar e comunitário em um município do noroeste paulista" /". São José do Rio Preto : [s.n.], 2010. http://hdl.handle.net/11449/94851.

Testo completo
Abstract (sommario):
Orientador: Mara Corrêa Lelles Nogueira
Banca: Doroti de Oliveira Garcia
Banca: Fátima Pereira de Souza
Resumo: As Enterobacteriaceae constituem um importante grupo de patógenos humanos, causadores de infecções hospitalares e comunitárias. Nestas bactérias, a produção de beta-lactamases de espectro estendido (ESBL) é um dos principais mecanismos de resistência aos antibióticos, e responsável pela falha da terapia antimicrobiana. Enterobactérias resistentes a antibióticos são encontradas em águas superficiais e apresentam alta prevalência em águas servidas, inclusive pós-tratamento. Esta realidade caracteriza-se como um importante problema de saúde pública, pois estes ambientes atuam como reservatórios de patógenos humanos e de genes de resistência que se disseminam horizontalmente. Crescentes evidências mostram a relação entre a disseminação ambiental de bactérias resistentes e genes de resistência e a evolução da resistência em bactérias de importância clínica. Este estudo investigou a diversidade de enterobactérias produtoras de ESBL e a presença dos genes blaSHV, blaTEM, blaCTX-M e blaGES em amostras de água coletadas de efluentes hospitalar e comunitário em um município localizado na região noroeste do estado de São Paulo. Genes de resistência foram detectados em várias espécies de Enterobacteriaceae apresentando resistência a diversas classes de antimicrobianos. Estes dados indicam a necessidade de adoção de medidas para o controle da disseminação de bactérias resistentes a antimicrobianos e seus genes no meio ambiente.
Abstract: The Enterobacteriaceae constitutes an important group of human patogens, causing of hospital and communitarian infections. In these bacteria, the production of extended spectrum beta-lactamases (ESBL) is one of the main mechanisms of resistance the antibiotics, responsible for the imperfection of the therapy against infections for gram-negative bacilli. Enterobacteria resistant the antibiotics are found in superficial waters and present high prevalence in served waters, also post-cure. This reality is characterized as an important problem of public health, therefore these environments act as reservoirs of human patogens and genes of resistance that if spread through horizontal transmission. Increasing evidences show the relation between the ambient dissemination of resistant bacteria and genes of resistance and the evolution of the resistance in bacteria of clinical importance. This study it investigated the diversity of producing Enterobacteria of ESBL and the presence of the genes blaSHV, blaTEM, blaCTX-M and blaGES in water samples collected in the system of sewers in a city located in the region the northwest of the state of São Paulo. The respective genes of resistance had been detected in several strains producing of ESBL presenting profile of multiple resistant to the diverse antimicrobials groups, suggesting the necessity of the surveillance and the adoption of measures for the control of the dissemination of the genes of resistance in the environment.
Mestre
Gli stili APA, Harvard, Vancouver, ISO e altri
4

Braga, Jisbaque Melo. "Prevalência e sensibilidade antimicrobiana de escherichia coli e klebsiella pneumoniae isoladas de infecções nosocomiais no hospital regional norte em sobral/ce e detecção genética de blatem, blashv blactx-m e blages em espécimes produtores de betalactamase de espectro estendido (esbl)". reponame:Repositório Institucional da UFC, 2016. http://www.repositorio.ufc.br/handle/riufc/22878.

Testo completo
Abstract (sommario):
BRAGA, J.M. Prevalência e sensibilidade antimicrobiana de escherichia coli e klebsiella pneumoniae isoladas de infecções nosocomiais no hospital regional norte em sobral/ce e detecção genética de blatem, blashv blactx-m e blages em espécimes produtores de betalactamase de espectro estendido (esbl). 2016. 101f. Dissertação (Mestrado em Ciências da Saúde) – Campus de Sobral, Universidade Federal do Ceará, Sobral, 2016.
Submitted by Mestrado Ciências da Saúde (ppgcsufcsobral@gmail.com) on 2017-05-25T14:15:01Z No. of bitstreams: 1 2016_dis_jmbraga.pdf: 4368780 bytes, checksum: f1881d9ef6d76e8cb665b910b9dcd076 (MD5)
Approved for entry into archive by Djeanne Costa (djeannecosta@gmail.com) on 2017-05-26T18:41:29Z (GMT) No. of bitstreams: 1 2016_dis_jmbraga.pdf: 4368780 bytes, checksum: f1881d9ef6d76e8cb665b910b9dcd076 (MD5)
Made available in DSpace on 2017-05-26T18:41:29Z (GMT). No. of bitstreams: 1 2016_dis_jmbraga.pdf: 4368780 bytes, checksum: f1881d9ef6d76e8cb665b910b9dcd076 (MD5) Previous issue date: 2016-12-01
Escherichia coli and Klebsiella pneumoniae are Gram-negative bacilli account for a significant portion of infections in hospitals. Its importance has increased due to increased production of beta-lactamases of extended spectrum (ESBL). These enzymes are produced by some Gram negative bacilli and mediate resistance to beta-lactams, such as cephalosporins and aztreonam. In these pathogens, the majority of the ESBL identified are TEM, SHV and CTX-M types. This study aimed to analyze the prevalence and antimicrobial susceptibility of E. coli and K. pneumoniae isolated from nosocomial infections in North Regional Hospital in Sobral/CE, Brazil, from March 2015 to March 2016, and to detect blaTEM, blaSHV, blaCTX-M, blaKPC, blaVIM and blaGES genes of isolates which exhibited ESBL phenotype. A total of 245 isolates (132 E. coli and 113 K. pneumoniae) were analyzed. Of these, 145 (59.1%) had ESBL phenotype and 44 were characterized genetically by presence of blaTEM, blaSHV, blaCTX-M, blaKPC, blaVIM and blaGES genes. The rates of E.coli and Klebsiella pneumoniae ESBL producers were 49.2% and 70.8%, respectively. This research revealed that ESBL-producing E. coli strains were more sensitive to meropenem (100%), amikacin (96.9%), colistin (90.8%) and tigecycline (90.8%), and more resistant to ampicillin (100%), ceftriaxone (100%) and cefepime (96.9%). On the other hand, K. pneumoniae ESBL producers were more sensitive to colistin (100%), amikacin (96.2%) and meropenem (93.7%), and more resistant to ceftriaxone (100%), ceftazidime (100%), cefepime (98.7%) and ampicillin (98.7%). The blaCTX-M gene was detected in 14 (31.8%) isolates, blaTEM and blaSHV genes were detected both in 3 specimens (6.8%), the blaGES gene was detected in only one isolate (2.2%), while blaKPC and blaVIM genes were not detected. Our findings show high levels of resistance to beta-lactam antibiotics, as well as increasing linear trend for ESBL production by the studied species. The gene with the highest detection rates among the isolates was blaCTX-M gene, which is certainly the most important ESBL gene today. We detected one strain of Klebsiella pneumoniae harboring blaGES and blaCTX-M genes, being of our knowledge the first report in Brazil, which demonstrates the great potential for worldwide spread of resistance genes between Gram-negative bacillus.
Escherichia coli e Klebsiella pneumoniae são bacilos Gram-negativos responsáveis por uma parcela significante de infecções em ambiente hospitalar. Sua importância aumentou devido ao surgimento de espécimes produtoras de betalactamases de espectro estendido (ESBL). Essas enzimas são produzidas por alguns bacilos Gram-negativos e conferem resistência aos betalactâmicos, como cefalosporinas e aztreonam. Nesses patógenos, a maioria das ESBL identificadas é do tipo TEM, SHV e CTX-M. Este estudo teve como objetivo analisar a prevalência e a sensibilidade antimicrobiana de E.coli e K. pneumoniae isoladas de infecções nosocomiais do Hospital Regional Norte, Sobral/CE, Brasil no período de março de 2015 a março de 2016, assim como realizar a detecção dos genes blaTEM, blaSHV, blaCTX-M, blaKPC, blaVIM e blaGES nos isolados que exibiram fenótipo ESBL. No total, 245 isolados (132 E. coli e 113 K. pneumoniae) foram analisados. Destes, 145 (59,1%) apresentaram fenótipo ESBL e 44 foram caracterizados geneticamente quanto à detecção dos genes blaTEM, blaSHV, blaCTX-M, blaKPC, blaVIM e blaGES. As taxas de produção de ESBL por E.coli e K. pneumoniae foram 49,2% e 70,8%, respectivamente. Essa pesquisa revelou que E.coli produtoras de ESBL foram mais sensíveis ao meropenem (100%), amicacina (96,9%), colistina (90,8%) e tigeciclina (90,8%), e mais resistentes à ampicilina (100%), ceftriaxona (100%) e cefepima (96,9%). Já K. pneumoniae produtoras de ESBL foram mais sensíveis à colistina (100%), amicacina (96,2%) e meropenem (93,7%), e mais resistentes à ceftriaxona (100%), ceftazidima (100%), cefepima (98,7%) e ampicilina (98,7%). O gene blaCTX-M foi detectado em 12 (27,2%) isolados, os genes blaTEM e blaSHV foram detectados em 3 espécimes cada um (6,8%), o gene blaGES foi detectado em apenas um isolado (2,2%), enquanto os genes blaKPC e blaVIM não foram detectados. Nossos achados revelam altos índices de resistência aos betalactâmicos, assim como tendência linear crescente para produção de ESBL pelas espécies estudadas. O gene com maiores taxas de detecção entre os isolados foi o gene blaCTX-M que, certamente, é o gene ESBL mais importante clinicamente na atualidade. Nós detectamos um isolado de Klebsiella pneumoniae contendo o gene blaGES e blaCTX-M, sendo do nosso conhecimento o primeiro relato no Brasil, o que demonstra o grande potencial de disseminação mundial de genes de resistência entre bacilos Gram-negativos.
Gli stili APA, Harvard, Vancouver, ISO e altri
5

Blagoev, Blagoy [Verfasser]. "Arbeitszeitregime im Lock-in? : Eine pfadtheoretische Untersuchung der Persistenz überlanger Arbeitszeiten in einem Beratungsunternehmen / Blagoy Blagoev". Berlin : Freie Universität Berlin, 2016. http://d-nb.info/1099282845/34.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Hettasch, Georg. "Optimization of fir-tree-type turbine blade roots using photoelasticity". Thesis, Stellenbosch : University of Stellenbosch, 1992. http://hdl.handle.net/10019.1/993.

Testo completo
Abstract (sommario):
Thesis (MEng.)-- University of Stellenbosch, 1992. 140 leaves on single pages, preliminary pages i-xi and numbered pages 1-113. Includes bibliography. Digitized at 600 dpi grayscale to pdf format (OCR),using an Bizhub 250 Konica Minolta Scanner and at 300 dpi grayscale to pdf format (OCR), using a Hp Scanjet 8250 Scanner.
Thesis (MEng (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 1992
ENGLISH ABSTRACT: The large variety of turbo-machinery blade root geometries in use in industry prompted the question if a optimum geometry could be found. An optimum blade root was defined as a root with a practical geometry which, when loaded, returns the minimum fillet stress concentration factor. A literature survey on the subject provided guidelines but very little real data to work from. An initial optimization was carried out using a formula developed by Heywood to determine loaded projection fillet stresses. The method was found to produce unsatisfactory results, prompting a photoelastic investigation. This experimental optimization was conducted in two stages. A single tang defined load stage and a single tang in-rotor stage which modeled the practical situation. The defined load stage was undertaken in three phases. The first phase was a preliminary investigation, the second phase was a parameter optimization and the third phase was a geometric optimization based on a material utilization optimization. This material optimization approach produced good results. From these experiments a practical optimum geometry was defined. A mathematical model which predicts the fillet stress concentration factor for a given root geometry is presented. The effect of expanding the single tang optimum to a three tang root was examined.
AFRIKAANSE OPSOMMING: Die groot verskeidenheid lemwortelgeometrieë wat in turbomasjiene gebruik word het die vraag na 'n optimum geometrie laat ontstaan. Vir hierdie ondersoek is 'n optimum geometrie gedefineer as 'n praktiese geometrie wat, as dit belas word, die mimimum vloeistukspanningskonsentrasiefaktor laat ontstaan. 'n Literatuur studie het riglyne aan die navorsing gegee maar het wynig spesifieke en bruikbare data opgelewer. Die eerste optimering is met die Heywood formule, wat vloeistukspannings in belaste projeksies bepaal, aangepak. Die metode het nie bevredigende resultate opgelewer nie. 'n Fotoelastiese ondersoek het die basis vir verdere optimeering gevorm. Hierdie eksperimentele optimering is in twee stappe onderneem. 'n Enkelhaak gedefineerde lasgedeelte en 'n enkelhaak in-rotor gedeelte het die praktiese situasie gemodeleer. Die gedefineerde lasgedeelte is in drie fases opgedeel. Die eerste fase was n voorlopige ondersoek. Die tweede fase was 'n parameter optimering. 'n Geometrie optimering gebasseer op 'n materiaal benuttings minimering het die derde fase uitgemaak. Die materiaal optimerings benadering het goeie resultate opgelewer. Vanuit hierdie eksperimente is 'n optimum praktiese geometrie bepaal. 'n Wiskundige model is ontwikkel, wat die vloeistukspanningskonsentrasiefaktor vir 'n gegewe wortelgeometrie voorspel. Die resultaat van 'n geometriese uitbreiding van die enkelhaaklemwortel na 'n driehaaklemwortel op die spanningsverdeling is ondersoek.
Gli stili APA, Harvard, Vancouver, ISO e altri
7

Bose, Anushika. "Birds & Blades". Doctoral thesis, Humboldt-Universität zu Berlin, 2021. http://dx.doi.org/10.18452/22458.

Testo completo
Abstract (sommario):
Kollisionen von Vögeln mit Windturbinen haben sich zu einer bedenklichen Quelle für die Gefährdung besonders von Populationen seltenerer Vogelarten entwickelt. Allerdings wird im Allgemeinen auch bestätigt, dass die Nutzung der Windenergie unverzichtbar ist. Das Hauptziel dieser Arbeit war es, die Relevanz der Wechselwirkungen zu verstehen, die zwischen technischen Infrastrukturen und den von Kollisionen betroffenen Vogelarten auf der Landschaftsebene stattfinden. Da sowohl von der Landschaft beeinflusst werden. Unter Nutzung der durch gezielte Nachsuche gefundenen Opfer der am häufigsten von Kollisionen betroffenen Artengruppen paradoxerweise as als Proxy für das Vorkommen von Arten, und Durch die Anwendung verschiedener Techniken zur Modellierung der Artenverbreitung (SDMs) die “kollisionsempfindliche Nische “für jede der Vogelgruppen beschrieben. Obwohl die vorhergesagten Gebiete mit potenziellen Kollisionsrisiko insgesamt nur kleine, aber stark verteilt im ungefährdes Bundeslandes hatten. Greifvögel mit die breiteste Nische, die zudem signifikante Überlappungen mit den kollisionsempfindlichen Nischen der anderen Gruppen aufwies. Die niedrig bewerteten Gebiete weiter differenziert, die als tatsächliche „Bereiche ohne Risiko“ interpretiert wurden, für weitere geplante Winkraftanlagen. Zusätzlich die jeweiligen Potentiale und Gefärdungen für Kollisionen auf der Basis der regionalen Dichteverteilungen der Arten in Brandenburg mit Ensemble-Methoden von Boosted Regression Trees wird ebenfalls bewertet. Zusammenfassend, diese Analysen paradigmatisch, sowohl die Gebiete als auch die Entfernungen zu den Grenzlinien der verschiedenen Landnutzungsformen ein höheres Risiko für die Kollision von Individuen der untersuchten Arten mit Windkraftanlagen ergibt ermitteln . Dieser Ansatz kann es möglich machen, zukünftige Windparkerweiterungen in der Landschaft im die möglichst kollisionsfreie und naturverträglicheStandorte in der Landschaft.
Although, it is well recognized that harnessing wind energy is highly indispensable, but collisions of birds at wind turbines has also developed simultaneously, concerning multiple bird species. With wind being strongly affected by the landscape and the behaviour of birds also being strongly influenced by the landscape, the main objective of the thesis was to understand the relevance of interactions between wind energy infrastructures and bird species from an ecological perspective of the landscape. Utilizing the carcass collision datasets of the frequently-hit bird-groups paradoxically as proxies for species presence, collision sensitive ecological distances to different land-use types were ascertained, by employing multiple techniques of species distribution modelling (SDMs), to delineate their respective collision sensitive niche employing the capabilities of machine learning algorithms. The predicted areas were specialized and highly dispersed across the federal state, with raptors showing the broadest niche and significant overlaps with the other groups. Based on estimated collision probabilities of the assessed areas (between 0 and 1), further segregations differentiated only those areas with negligible collision probabilities, <0.05, which were interpreted as the actual "no risk areas, suggesting any further planned additions of wind turbines to be suitably positioned only in these “safer” areas. Additionally, these collision probabilities were translated to strike susceptibilities, by relating them to the regional density distributions of the species as well. Summarizing, these analyses paradigmatically ascertained collision risk areas, and especially the collision sensitive distances from different land-use types to these areas, enabling the accurate guidance of future wind farm expansions in the landscape. Ultimately, formulating novel wind turbine allocation strategies to minimize avian collisions, making them as compatible as possible.
Gli stili APA, Harvard, Vancouver, ISO e altri
8

Drude, Matthias, e Else Lasker-Schüler. "Mein blaues Klavier: (1986)". Matthias Drude, 2018. https://slub.qucosa.de/id/qucosa%3A17093.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
9

Birgmark, Anja. "Wear of Coater Blades". Thesis, Karlstads universitet, Fakulteten för teknik- och naturvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-27183.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Medd, Adam Jon. "Inverse design of turbomachinery blades". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0010/MQ34391.pdf.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Più fonti

Libri sul tema "Blages"

1

Finlay, Ian Hamilton. Blades. Little Sparta, Dunsyre: Wild Hawthorn Press, 1989.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Tyler, Ben. Gay blades. New York: Kensington Books, 2003.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Rubén Blades. New York: Chelsea House, 1992.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
4

Aki, a cura di. Méga blagues. Paris: Gründ, 2014.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
5

Tyler, Ben. Gay blades. New York: Kensington, 2004.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Dunne, Nicola. Pine-blades. [London]: [Dunne], 1994.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
7

McCullough, Kelly. Drawn blades. New York: Ace Books, 2014.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
8

Cutting blades. Long Preston, North Yorkshire: Magna Large Print Books, 2005.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
9

Pereda, Raquel. Blanes Viale. Montevideo, Uruguay: Fundación Banco de Boston, 1990.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Cutting blades. New York: Berkley Prime Crime, 2006.

Cerca il testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Più fonti

Capitoli di libri sul tema "Blages"

1

Renneberg, Reinhard, e Iris Rapoport. "Blaues Blut". In Bio, Biio, Biiio!, 72–74. Berlin, Heidelberg: Springer Berlin Heidelberg, 2018. http://dx.doi.org/10.1007/978-3-662-58188-9_22.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Hau, Erich. "Rotor Blades". In Wind Turbines, 269–304. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-27151-9_8.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Hau, Erich. "Rotor Blades". In Windturbines, 183–209. Berlin, Heidelberg: Springer Berlin Heidelberg, 2000. http://dx.doi.org/10.1007/978-3-662-04257-1_7.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
4

Koch, Grady, e Elias Koch. "Airfoil Blades". In LEGO Wind Energy, 57–65. Berkeley, CA: Apress, 2019. http://dx.doi.org/10.1007/978-1-4842-4439-5_4.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
5

Dannenberg, Lothar. "Rotor Blades". In Understanding Wind Power Technology, 162–201. Chichester, UK: John Wiley & Sons, Ltd, 2014. http://dx.doi.org/10.1002/9781118701492.ch5.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Sluga, Hans. "Wittgensteins Blaues Buch". In The Tasks of Contemporary Philosophy / Die Aufgaben der Philosophie in der Gegenwart, 411–19. Munich: J.F. Bergmann-Verlag, 1986. http://dx.doi.org/10.1007/978-3-662-30341-2_77.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
7

Gooch, Jan W. "Pinch-Off Blades". In Encyclopedic Dictionary of Polymers, 537. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-6247-8_8745.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
8

Goldschmidt, D. "Single-Crystal Blades". In Materials for Advanced Power Engineering 1994, 661–74. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-1048-8_55.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
9

Andriopoulos, Thodoris. "Blaise". In Who Killed Professor X?, 53–58. Basel: Springer Basel, 2014. http://dx.doi.org/10.1007/978-3-0348-0884-2_7.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Aumasson, Jean-Philippe, Willi Meier, Raphael C. W. Phan e Luca Henzen. "BLAKE2". In Information Security and Cryptography, 165–83. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-662-44757-4_9.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri

Atti di convegni sul tema "Blages"

1

Murthy, Raghavendra, e Marc P. Mignolet. "Decreasing Bladed Disk Response With Dampers on a Few Blades: Part II—Nonlinear and Blade-Blade Dampers Applications". In ASME Turbo Expo 2012: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/gt2012-69797.

Testo completo
Abstract (sommario):
This two part paper focuses on the optimum placement of a limited number of dampers, i.e. fewer than the number of blades, on a bladed disk to induce the smallest possible amplitude of blade response with or without involuntary, random mistuning. Intentional mistuning is also considered as an option to reduce the amplitude of blade response and the pattern of two blade types (referred to as A and B blades) is then part of the optimization effort in addition to the location of the dampers on the disk. This second part of the investigation focuses on the application of the optimization algorithms developed in Part I to nonlinear dampers, more specifically friction dampers, as well as to the consideration of blade-blade dampers, linear or nonlinear (underplatform dampers). Additionally, the optimization of blade-only and blade-blade linear dampers will be extended to include uncertainty/variability in the damper properties that arise during the manufacturing and/or inservice. It is found that the optimum achieved without considering such uncertainty/variability is robust with respect to it.
Gli stili APA, Harvard, Vancouver, ISO e altri
2

Murthy, Raghavendra, e Marc P. Mignolet. "Decreasing Bladed Disk Response With Dampers on a Few Blades: Part I—Optimization Algorithms and Blade-Only Dampers Applications". In ASME Turbo Expo 2012: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/gt2012-69789.

Testo completo
Abstract (sommario):
This two part paper focuses on the optimum placement of a limited number of dampers, i.e. fewer than the number of blades, on a bladed disk to induce the smallest possible amplitude of blade response with or without involuntary, random mistuning. Intentional mistuning is also considered as an option to reduce the amplitude of blade response and the pattern of two blade types (referred to as A and B blades) is then part of the optimization effort in addition to the location of the dampers on the disk. This first part focuses on the formulation and validation of dedicated algorithms for the selection of the damper locations and, when appropriate, of the intentional mistuning pattern. Given the limited number of dampers, there is a concern that the failure of one or several of them could lead to a sharp rise in blade response and this issue is addressed by including the possibility of damper failure in the optimization process to yield a fail-safe optimized solution. The high efficiency and accuracy of the optimization algorithms is assessed in comparison with computationally very demanding exhaustive search results.
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Kaneko, Y., K. Mori, H. Ohyama e E. Watanabe. "Vibrational Response Analysis of Mistuned Bladed Disk System of Grouped Blades". In ASME 1998 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/98-gt-410.

Testo completo
Abstract (sommario):
For the purpose of the efficient analysis of a mistuned bladed disk system, a new analysis method which applies the substructure synthesis method and the modal analysis method is proposed. Using the proposed method, the vibrational characteristics of the grouped blades structure are studied. From the results, it is found that the grouped blades structure is very sensitive to the mistuning. It is also found that the mixed grouped blades structure (a bladed disk system consisting of some different types of grouped blades relating to the number of blades contained) has an undesirable effect on the forced response. Moreover, by comparing the vibrational characteristics of the integral shroud blades (ISB) structure with those of the grouped blades structure, it is clarified that the reliability of the ISB structure is superior to other structures also from the viewpoint of the mistuning.
Gli stili APA, Harvard, Vancouver, ISO e altri
4

Kaneko, Yasutomo, Kazushi Mori e Hiroharu Ooyama. "Resonant Response and Random Response Analysis of Mistuned Bladed Disk Consisting of Directionally Solidified Blade". In ASME Turbo Expo 2015: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/gt2015-42875.

Testo completo
Abstract (sommario):
Recently, DS (Directionally Solidified) and SC (Single Crystal) alloys have been widely applied for gas turbine blades instead of CC (Conventional Casting) alloys, in order to improve the creep rupture strength. The DS blade consists of several columnar grains of SC, where the growing direction of the columnar crystal is set to the direction of the centrifugal force. Because the elastic constants of the DS blade are anisotropic, the mistuning characteristics of the bladed disk consisting of the DS blades seem to be different from those of the CC blade. In this study, the resonant response and random response analysis of mistuned bladed disks consisting of the DS blades are carried out, considering the deviations of the elastic constants and the crystal angle of the DS blade. The FMM (Fundamental Mistuning Model) and the conventional modal analysis method are used to analyze the vibration response of the mistuned bladed disk. The maximum resonant response and random response of the mistuned bladed disk consisting of the DS blades are estimated by the Monte Carlo simulation combining with the response surface method. These calculated results for the DS blades are compared with those of the CC blades. From these results, it is concluded that the maximum response of the mistuned bladed disk consisting of the DS blades is the nearly same as that of the CC blades. However, in the design of the tuned blade, where the blade resonance should be avoided, it is necessary to consider that the range of the resonant frequency of the DS blade becomes wider than that of the CC blade.
Gli stili APA, Harvard, Vancouver, ISO e altri
5

Salhi, Bendali, Marc Berthillier, Joseph Lardies, Philippe Voinis e Charles Bodel. "A Subspace Method for Modal Identification of Bladed Assemblies Using Blade Tip-Timing Data". In ASME Turbo Expo 2007: Power for Land, Sea, and Air. ASMEDC, 2007. http://dx.doi.org/10.1115/gt2007-28151.

Testo completo
Abstract (sommario):
Unknown excitation forces are applied to bladed disk assemblies, such as turbines blades, leading to forced vibration responses. Non contact measurement of such vibrations using blade tip-timing data has become an industrial standard procedure and current research focuses on analysis methods for interpretation of measured vibrations. Our purpose is to develop a method for identification of the blade’s natural frequencies and damping ratios using blade tip-timing data. The method is based on a subspace analysis. Its performance is compared to the traditional Fast Fourier Transform analysis. A detailed description of these methods and results are presented.
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Avalos, Javier, e Marc P. Mignolet. "On Damping Entire Bladed Disks Through Dampers on Only a Few Blades". In ASME Turbo Expo 2008: Power for Land, Sea, and Air. ASMEDC, 2008. http://dx.doi.org/10.1115/gt2008-51446.

Testo completo
Abstract (sommario):
The focus of this paper is on demonstrating the potential to damp entire bladed disks using dampers on only a fraction of the blades. This problem is first considered without the presence of random mistuning and it is demonstrated that a few dampers at optimized locations can lead to a significant reduction in the forced response of the entire bladed disk. Unfortunately, this optimum design may not be robust with respect to random mistuning and a notable fraction of the reduction in forced response obtained may disappear because of mistuning. To regain the reduction in forced response but with mistuning present, robustness to mistuning is enhanced by using intentional mistuning in addition to dampers. The intentional mistuning strategy selected here is the A/B pattern mistuning in which the blades all belong to either type A or B. An optimization effort is then performed to obtain the best combination of A/B pattern and damper location to minimize the mistuned forced response of the disk. The addition of intentional mistuning in the system is shown to be very efficient and the optimum bladed disk design does indeed exhibit a significant reduction of mistuned forced response as compared to the tuned system. These findings were obtained on both single-degree-of-freedom per blade disk models and a reduced order model of a blisk.
Gli stili APA, Harvard, Vancouver, ISO e altri
7

CHIANG, HSIAO-WEI, e SANFORD FLEETER. "Flutter control of incompressible flow turbomachine blade rows by splitter blades". In 27th Joint Propulsion Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 1991. http://dx.doi.org/10.2514/6.1991-1900.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
8

Georgiades, F., M. Peeters, G. Kerschen, J. C. Golinval e M. Ruzzene. "Localization of Energy in a Perfectly Symmetric Bladed Disk Assembly Due to Nonlinearities". In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-41649.

Testo completo
Abstract (sommario):
Although a bladed disk is typically designed to have identical blades, manufacturing tolerances, wear, and other causes may cause random deviations among the blades. The blade-to-blade discrepancies, denoted as mistuning, lead to vibratory responses mostly concentrated in small regions of the bladed-disk assembly, according to a phenomenon called localization. The resulting spatial confinement of the vibration energy causes the responses of some blades to become dangerously high and increases the amplitude of the bladed-disk assembly’s overall response. The attendant increase in stresses can lead to premature high cycle fatigue (HCF) of the blades. In this study we investigate whether vibration localization in a perfectly symmetric bladed disk assembly may occur in the presence of nonlinearity. To this end, the nonlinear normal modes (NNMs) of a simplified model of a bladed disk assembly are computed. The NNMs are then carefully examined to highlight possible vibration localization phenomena.
Gli stili APA, Harvard, Vancouver, ISO e altri
9

Kharyton, Vsevolod, Jean-Pierre Laine, Fabrice Thouverez e Olexiy Kucher. "Cracked Blade Detection From Bladed Disk Forced Response". In ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-59598.

Testo completo
Abstract (sommario):
The primary task of this study is to offer reliable and accurate model of a bladed disk containing cracked blade. This model allows simulation of bladed disk dynamic behavior for various crack positions and lengths. Due to absence of cyclic symmetry caused by crack presence in the disk, a reduction procedure was implemented to simulate full bladed disk. It is proposed to use crack location as an interface between two substructures for subsequent fixed-interface method application. Harmonic balance method was applied to take into account crack nonlinear behavior under periodically varying loads. The method implementation considers contact interaction between crack sides at the crack being closed. The contact force is calculated using penalty method of contact force calculation. Relative vertical displacements between nodes in contact were used as nonlinear degrees of freedom (DOFs). Developed bladed disk model is able to take into account external excitation forces phase lag caused by difference between number of rotor and stator blades. Also presence of mistuning was considered. It was shown that certain level of mistuning can directly affect cracked blade detectability. Cracked blade dynamic behavior localization plays here very important role. Absence of cracked blade localization results in impossibility to separate cracked blade response at any mistuning level. Validity of zig-zag diagram for structures with disrupted symmetry is shown using developed bladed disk model with presence of certain level of mistuning.
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Kubin, Zdenek, Vaclav Polreich, Vaclav Cerny, Petra Babkova e Lubos Prchlik. "Damping Identification and its Comparison for Various Types of Blade Couplings". In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-95438.

Testo completo
Abstract (sommario):
Regarding steam turbine blade vibrations, damping of blade as well as bladed disc mode shapes is one of the most important parameters in terms of steam turbine operation. A value of the parameter depends on properties of material used for manufacturing and construction elements of the blades and the discs such as blade roots, shrouds, tiebosses (snubbers) and dampers. This article deals with a comparison of damping of mode shapes for particular blade couplings and shows which methods are suitable for determination of the damping in individual cases. The whole identification procedure of the damping together with its specifics is also presented. At first, an identification technique of material damping ratio is introduced and its results are given for different materials. The material damping ratio is assessed as material strain dependent. Subsequently, damping ratio of bladed disc mode shapes under bladed disc rotation is identified taking into account two alternatives. The alternatives differ in such a way that blades have been free for the first time and then coupled with friction dampers. Outcomes presented in the article illustrate good agreement between damping ratio of bladed disc mode shapes with free blades and material used for manufacturing of the blades. On the other hand, damping ratio of bladed disc mode shapes with friction dampers is significantly different and strongly dependent on blade vibration amplitudes as well as nodal diameters of bladed disc mode shapes. Finally, nonlinear behavior of the bladed disc has been revealed along large blade vibration amplitudes and higher nodal diameters of the disc. The non-linear behavior manifests itself in such a way that values of natural frequencies of the disc have become dependent on blade vibration amplitudes.
Gli stili APA, Harvard, Vancouver, ISO e altri

Rapporti di organizzazioni sul tema "Blages"

1

Bir, G., e P. Migliore. Preliminary Structural Design of Composite Blades for Two- and Three-Blade Rotors. Office of Scientific and Technical Information (OSTI), settembre 2004. http://dx.doi.org/10.2172/15009673.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
2

ASHWILL, THOMAS D. Parametric Study for Large Wind Turbine Blades: WindPACT Blade System Design Studies. Office of Scientific and Technical Information (OSTI), agosto 2002. http://dx.doi.org/10.2172/801402.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
3

Desmond, M., S. Hughes e J. Paquette. Structural Testing of the Blade Reliability Collaborative Effect of Defect Wind Turbine Blades. Office of Scientific and Technical Information (OSTI), giugno 2015. http://dx.doi.org/10.2172/1215097.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
4

GRIFFIN, DAYTON A., e THOMAS D. ASHWILL. Blade System Design Studies Volume I: Composite Technologies for Large Wind Turbine Blades. Office of Scientific and Technical Information (OSTI), luglio 2002. http://dx.doi.org/10.2172/800994.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
5

Cao, Yiding. An Innovative Turbine Blade Cooling Technology and Micro/Miniature Heat Pipes for Turbine Blades. Fort Belvoir, VA: Defense Technical Information Center, luglio 2000. http://dx.doi.org/10.21236/ada381455.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
6

Smith, Kevin J., e Dayton A. Griffin. Supersized Wind Turbine Blade Study: R&D Pathways for Supersized Wind Turbine Blades. Office of Scientific and Technical Information (OSTI), marzo 2019. http://dx.doi.org/10.2172/1498695.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
7

Bir, G. S. User's Guide to MBC3: Multi-Blade Coordinate Transformation Code for 3-Bladed Wind Turbine. Office of Scientific and Technical Information (OSTI), settembre 2010. http://dx.doi.org/10.2172/989416.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
8

Zhu, Qi, e Kathryn Rominger. Tensioned Fabric Wind Blades. Office of Scientific and Technical Information (OSTI), gennaio 2015. http://dx.doi.org/10.2172/1171704.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
9

ASHWILL, THOMAS D. Cost Study for Large Wind Turbine Blades. Office of Scientific and Technical Information (OSTI), maggio 2003. http://dx.doi.org/10.2172/811158.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
10

Ho, Chih-Ming. Control of Interactions between Wake and Blades. Fort Belvoir, VA: Defense Technical Information Center, settembre 1997. http://dx.doi.org/10.21236/ada329882.

Testo completo
Gli stili APA, Harvard, Vancouver, ISO e altri
Ti possono interessare anche gli elenchi estesi di opere sul tema "Blages":
Articoli di riviste Tesi Libri
Offriamo sconti su tutti i piani premium per gli autori le cui opere sono incluse in raccolte letterarie tematiche. Contattaci per ottenere un codice promozionale unico!

Vai alla bibliografia