17 research outputs found
A New Approach for Broken Bar Fault Detection in Three-Phase Induction Motor Using Instantaneous Power Monitoring under Low Slip Range
The majority of research is about the detection of broken bar fault in three-phase induction motor at high slip. Thus, it becomes very interesting and demanding to detect faults in case of low slip range. In this study, a novel investigation of broken bar faults using instantaneous power is presented. The method is based on calculations and frequency analysis of partial and total instantaneous power under low slip range. The used model of squirrel cage induction machine takes into account the geometry and winding layout. This model will be used to analyze the impact of broken bar on instantaneous power spectrum. The proposed ideas in this paper are veriïŹed experimentally. The results show that broken bar fault can be more reliably detected under low slip range when using a large frequency area of both partial and total instantaneous power spectrums.DOI:http://dx.doi.org/10.11591/ijece.v4i1.461
EMMPRIN/CD147 is a novel coreceptor of VEGFR-2 mediating its activation by VEGF
EMMPRIN/CD147 is mainly known for its protease inducing function but a role in promoting tumor angiogenesis has also been demonstrated. This study provides evidence that EMMPRIN is a new coreceptor for the VEGFR-2 tyrosine kinase receptor in both endothelial and tumor cells, as it directly interacts with it and regulates its activation by its VEGF ligand, signalling and functional consequences both in vitro and in vivo. Computational docking analyses and mutagenesis studies identified a molecular binding site in the extracellular domain of EMMPRIN located close to the
cell membrane and containing the amino acids 195/199. EMMPRIN is overexpressed in cancer and hence is able to further potentiate VEGFR-2 activation, suggesting that a combinatory therapy of an antiangiogenic drug together with an inhibitor of EMMPRIN/VEGFR-2 interaction may have a greater impact on inhibiting angiogenesis
and malignancy.This work was supported by Institut National de la Santé et de la Recherche Médicale (INSERM), La Ligue Nationale contre le Cancer (LNCC), La Société Française de Dermatologie and Université Paris Diderot. F.K was supported by a PhD fellowship from CancéropÎle-Ile de France and from Fondation ARC pour la Recherche sur le Cancer. L.P.C was supported by a FPU fellowship from
Spanish Ministry of Science. This work was supported by grant BIO2010â22324 from Plan NacionalI+D+iMICINN.
We thank the core facility of the Institut
Universitaire dâHĂ©matologie for confocal microscopy analyses. The core facility is supported by grants from the Association Saint-Louis, Conseil Regional dâIle-de-France, and the MinistĂšre de la Recherche.Peer ReviewedPostprint (published version
Formal Specification of Communication Protocols with Object-Based ECATNets
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Vers une synthÚse modulaire des superviseurs des systÚmes a événements discrets: simulation a l'aide du langage MAUDE
The Propagation Mechanism of Fault Signatures in Squirrel Cage Induction Motor Drives
International audienceThis work presents a new approach for analyzing the propagation mechanism of fault signatures in squirrel cage induction motor drives. The used method is based on the analysis of different currents of solid states converters and the fault signatures are investigated when motor is supplied by the volt-per-hertz control mode. Analytical expressions of currents at different location for broken bar, mixed air-gap eccentricity, unbalanced voltage supply are developed using switching functions of both inverter and diode rectifier. Experimental results are provided throughout the paper, to underpin the theoretical analysis. The results show that capacitor current spectrum can give useful information about the state of squirrel cage induction motor. However, due to the low-pass filter composed by capacitor only the fault signatures at low frequency range can be detected from the rectifier supply line current spectrum
Underlying mechanisms of glucocorticoid-induced beta-cell death and dysfunction: a new role for glycogen synthase kinase 3
International audienceGlucocorticoids (GCs) are widely prescribed for their anti-inflammatory and immunosuppressive properties as a treatment for a variety of diseases. The use of GCs is associated with important side effects, including diabetogenic effects. However, the underlying mechanisms of GC-mediated diabetogenic effects in beta-cells are not well understood. In this study we investigated the role of glycogen synthase kinase 3 (GSK3) in the mediation of beta-cell death and dysfunction induced by GCs. Using genetic and pharmacological approaches we showed that GSK3 is involved in GC-induced beta-cell death and impaired insulin secretion. Further, we unraveled the underlying mechanisms of GC-GSK3 crosstalk. We showed that GSK3 is marginally implicated in the nuclear localization of GC receptor (GR) upon ligand binding. Furthermore, we showed that GSK3 regulates the expression of GR at mRNA and protein levels. Finally, we dissected the proper contribution of each GSK3 isoform and showed that GSK3 beta isoform is sufficient to mediate the pro-apoptotic effects of GCs in beta-cells. Collectively, in this work we identified GSK3 as a viable target to mitigate GC deleterious effects in pancreatic beta-cells
CD147 Promotes Tumor Lymphangiogenesis in Melanoma via PROX-1
International audienceMalignant melanoma is one of the most aggressive skin cancers and is characterized by early lymph node metastasis and the capacity to develop resistance to therapies. Hence, understanding the regulation of lymphangiogenesis through mechanisms contributing to lymphatic vessel formation represents a treatment strategy for metastatic cancer. We have previously shown that CD147, a transmembrane glycoprotein overexpressed in melanoma, regulates the angiogenic process in endothelial cells. In this study, we show a correlation between high CD147 expression levels and the number of lymphatic vessels expressing LYVE-1, Podoplanin, and VEGFR-3 in human melanoma lymph nodes. CD147 upregulates in vitro lymphangiogenesis and its related mediators through the PROX-1 transcription factor. In vivo studies in a melanoma model confirmed that CD147 is involved in metastasis through a similar mechanism as in vitro. This study, demonstrating the paracrine role of CD147 in the lymphangiogenesis process, suggests that CD147 could be a promising target for the inhibition of melanoma-associated lymphangiogenesi
Concomitant alpha7 and beta2 nicotinic AChR subunit deficiency leads to impaired energy homeostasis and increased physical activity in mice
Nicotinic acetylcholine receptors (nAChRs) are pentameric ligand-gated cation channels well characterized in neuronal signal transmission. Moreover, recent studies have revealed nAChR expression in nonneuronal cell types throughout the body, including tissues involved in metabolism. In the present study, we screen gene expression of nAChR subunits in pancreatic islets and adipose tissues. Mice pancreatic islets present predominant expression of α7 and ÎČ2 nAChR subunits but at a lower level than in central structures. Characterization of glucose and energy homeostasis in α7ÎČ2nAChR(-/-) mice revealed no major defect in insulin secretion and sensitivity but decreased glycemia apparently unrelated to gluconeogenesis or glycogenolysis. α7ÎČ2nAChR(-/-) mice presented an increase in lean and bone body mass and a decrease in fat storage with normal body weight. These observations were associated with elevated spontaneous physical activity in α7ÎČ2nAChR(-/-) mice, mainly due to elevation in fine vertical (rearing) activity while their horizontal (ambulatory) activity remained unchanged. In contrast to α7nAChR(-/-) mice presenting glucose intolerance and insulin resistance associated to excessive inflammation of adipose tissue, the present metabolic phenotyping of α7ÎČ2nAChR(-/-) mice revealed a metabolic improvement possibly linked to the increase in spontaneous physical activity related to central ÎČ2nAChR deficiency
alpha3alpha5beta2-Nicotinic acetylcholine receptor contributes to the wound repair of the respiratory epithelium by modulating intracellular calcium in migrating cells
Nicotinic acetylcholine receptors (nAChRs), present in human bronchial epithelial cells (HBECs), have been shown in vitro to modulate cell shape. Because cell spreading and migration are important mechanisms involved in the repair of the bronchial epithelium, we investigated the potential role of nAChRs in the wound repair of the bronchial epithelium. In vivo and in vitro, alpha3alpha5beta2-nAChRs accumulated in migrating HBECs involved in repairing a wound, whereas alpha7-nAChRs were predominantly observed in stationary confluent cells. Wound repair was improved in the presence of nAChR agonists, nicotine, and acetylcholine, and delayed in the presence of alpha3beta2 neuronal nAChR antagonists, mecamylamine, alpha-conotoxin MII, and kappa-bungarotoxin; alpha-bungarotoxin, an antagonist of alpha7-nAChR, had no effect. Addition of nicotine to a repairing wound resulted in a dose-dependent transient increase of intracellular calcium in migrating cells that line the wound edge. Mecamylamine and kappa-bungarotoxin inhibited both the cell-migration speed and the nicotine-induced intracellular calcium increase in wound-repairing migrating cells in vitro. On the contrary alpha-bungarotoxin had no significant effect on migrating cells. These results suggest that alpha3alpha5beta2-nAChRs actively contribute to the wound repair process of the respiratory epithelium by modulating intracellular calcium in wound-repairing migrating cells