15 research outputs found

    Field verification of lateral-torsional coupling effects on rotor instabilities in centrifugal compressors

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    Lateral and torsional vibration data obtained on a centrifugal compressor train which had shaft instabilities and gear failures is examined. The field data verifies that the stability of centrifugal compressors can be adversely affected by coincidence of torsional natural frequencies with lateral instability frequencies. The data also indicates that excitation energy from gear boxes can reduce stability margins if energy is transmitted either laterally or torsionally to the compressors. The lateral and torsional coupling mechanisms of shaft systems is discussed. The coupling mechanisms in a large industrial compressor train are documented and the potential effect on rotor stability is demonstrated. Guidelines are set forth to eliminate these potential problems by minimizing the interaction of torsional and lateral responses and their effect on rotor stability

    Case Histories Of Specialized Turbomachinery Problems

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    PaperPg. 33-50.Vibration problems in turbomachinery occur due to many factors. Some of the problems could have been prevented if more detailed design analyses were performed. Other times the problems occur due to design extrapolations which are pushing the state of the art. The case histories of excessive vibrations and failures that will be discussed in this presentation are examples of those where additional design analyses would not necessarily have predicted or anticipated the problem that occurred because the analytical models are not sufficient to take into account all the variables

    Discovery and development of extreme selective inhibitors of the ITD and D835Y mutant FLT3 kinases

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    Aberrant activation of FMS-like tyrosine receptor kinase 3 (FLT3) is implicated in the pathogenesis of acute myeloid leukemia (AML) in 20-30% of patients. In this study we identified a highly selective (phenylethenyl)quinazoline compound family as novel potent inhibitors of the FLT3-ITD and FLT3-D835Y kinases. Their prominent effects were confirmed by biochemical and cellular proliferation assays followed by mice xenograft studies. Our modelling experiments and the chemical structures of the compounds predict the possibility of covalent inhibition. The most effective compounds triggered apoptosis in FLT3-ITD AML cells but had either weak or no effect in FLT3-independent leukemic and non-leukemic cell lines. Our results strongly suggest that our compounds may become therapeutics in relapsing and refractory AML disease harboring various ITD and tyrosine kinase domain mutations, by their ability to overcome drug resistance. (C) 2019 Elsevier Masson SAS. All rights reserved

    Effect of hydrolyzed infant formula vs conventional formula on risk of type 1 diabetes the TRIGR randomized clinical trial

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    IMPORTANCE Early exposure to complex dietary proteins may increase the risk of type 117 diabetes in children with genetic disease susceptibility. There are no intact proteins in extensively hydrolyzed formulas. OBJECTIVE To test the hypothesis that weaning to an extensively hydrolyzed formula decreases the cumulative incidence of type 117 diabetes in young children. DESIGN, SETTING, AND PARTICIPANTS An international double-blind randomized clinical trial of 211759 infants with human leukocyte antigen-conferred disease susceptibility and a first-degree relative with type 117 diabetes recruited from May 2002 to January 2007 in 78 study centers in 1175 countries; 11708117 were randomized to be weaned to the extensively hydrolyzed casein formula and 117078 to a conventional formula. The follow-up of the participants ended on February 28, 201177. INTERVENTIONS The participants received either a casein hydrolysate or a conventional adapted cow's milk formula supplemented with 20%of the casein hydrolysate. The minimum duration ofstudy formula exposure was 60 days by6 to 8 months ofage. MAINOUTCOMES ANDMEASURES Primary outcome was type 117 diabetes diagnosed according to World Health Organization criteria. Secondary outcomes included age at diabetes diagnosis and safety (adverse events). RESULTS Among 211759 newborn infants (11702117 female [47.3%]) who were randomized, 117744 (80.8%) completed the trial. The participants were observed for a median of 117117.5 years (quartile [Q] 117-Q3, 1170.2-1172.8). The absolute risk of type 117 diabetes was 8.4% among those randomized tothe casein hydrolysate (n = 9117) vs 7.6% among those randomized to the conventional formula (n = 82) (difference, 0.8% [95% CI, -117.6% to 3.2%]). The hazard ratio for type 117 diabetes adjusted for human leukocyte antigen risk group, duration of breastfeeding, duration of study formula consumption, sex, and region while treating study center as a random effect was 117.117 (95% CI, 0.8 to 117.5; P =.46). The median age at diagnosis of type 117 diabetes was similar in the 2 groups (6.0 years [Q117-Q3, 3.117-8.9] vs 5.8 years [Q117-Q3, 2.6-9.117]; difference, 0.2 years [95% CI, -0.9 to 117.2]). Upper respiratory infections were the most common adverse event reported (frequency, 0.48 events/year in the hydrolysate group and 0.50 events/year in the control group). CONCLUSIONS AND RELEVANCE Among infants at risk for type 117 diabetes, weaning to a hydrolyzed formula compared with a conventional formula did not reduce the cumulative incidence of type 117 diabetes after median follow-up for 117117.5 years. These findings do not support a need to revise the dietary recommendations for infants at risk for type 117 diabetes
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