Condition Monitoring of Squirrel-Cage Induction Motors Fed by PWM-Based Drives Using a Parameter Estimation Approach

Abstract: A rotor condition monitoring technique is presented in this paper based on a parameter estimation approach. In this technique, the stator currents, voltages and motor speed are used as the input signals, where the outputs will be the rotor\u27s inductance, resistance and consequently rotor time constant. This approach is verified by simulation of two different induction motor cases. These simulations are buttressed by experimental data obtained for a 2-hp induction motor in the case of healthy as well as one, three and five rotor bar breakages. In these tests, the induction motor was energized from a PWM-based drive, in order to demonstrate the capability of using this method for rotor condition monitoring purposes

Study on Prevalence of TTV among Cirrhotic patients due to Hepatitis B & C in Ahwaz University Hospitals during the Years 2004-2005

Background and Aims: Recently, a novel DNA virus was isolated from the serum of a patient with post-transfusion non A-G hepatitis and named TT virus. The aim of this study was to determine the prevalence TT virus among cirrhotic patients due to hepatitis B & C in infection Ahwaz. Methods: The prevalence of TTV infection was studied in 41 patients with liver cirrhosis. TTV DNA was detected by semi-nested PCR. The plasma samples were tested for marker hepatitis B & C by ELISA test. Results: TT virus was detected in 17(41.46%) of the 41 patients with cirrhotic liver disease. There were no significant difference between the subject TTV DNA in relation to sex and age. TTV positivity in cirrhotic patient infected with hepatitis B (52.9%) was higher than in similar patients infected with hepatitis C (47.1%). Conclusion: TTV infection was highly prevalence in patient with cirrhotic hepatitis, especially in those with hepatitis B virus infection

Designing an adaptive fuzzy control for robot manipulators using PSO

This paper presents designing an optimal adaptive controller for tracking control of robot manipulators based on particle swarm optimization (PSO) algorithm. PSO algorithm has been employed to optimize parameters of the controller and hence to minimize the integral square of errors (ISE) as a performance criteria. In this paper, an improved PSO using logic is proposed to increase the convergence speed. In this case, the performance of PSO algorithms such as an improved PSO (IPSO), an improved PSO using fuzzy logic (F-PSO), a linearly decreasing inertia weight of PSO (LWD-PSO) and a nonlinearly decreasing inertia weight of PSO (NDW-PSO) are compared in terms of parameter accuracy and convergence speed. As a result, the simulation results show that the F-PSO approach presents a better performance in the tracking control of robot manipulators than other algorithms

Evaluation of mRNA expression levels of cyp51a and mdr1, candidate genes for voriconazole resistance in Aspergillus flavus

Background: Voriconazole Resistance (VRC-R) in Aspergillus flavus isolates impacts the management of aspergillosis, since azoles are the first choice for prophylaxis and therapy. However, to the best of our knowledge, the mechanisms underlying voriconazole resistance are poorly understood. Objectives: The present study was designed to evaluate mRNA expression levels of cyp51A and mdr1 genes in voriconazole resistant A. flavus by a Real-Time Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) technique. Materials and Methods: Five A. flavus isolates with resistance to VRC were examined by a RT-PCR approach. Results: Four out of five isolates revealed cyp51A and mdr1 mRNA overexpression. Interestingly, the isolate, which was negative for cyp51A and mdr1 mRNA expression showed a high voriconazole Minimum Inhibitory Concentration (MIC). Furthermore, a computational-based analysis predicted that voriconazole resistance could be mediated through cooperation with a network protein interaction. Conclusions: Our experimental and in silico findings may provide new insight in the complex molecular pathways of drug resistance and also could assist design an efficient therapeutic strategy for aspergillosis treatment. © 2015 Ahvaz Jundishapur University of Medical Sciences

OPTIMIZATION OF A CULTURE MEDIUM FOR BIOMASS AND δ-ENDOTOXIN PRODUCTION BY A RECOMBINANT ESCHERICHIA COLI STRAIN

A recombinant strain of Escherichia coli harboring a plasmid containing the Bacillus thuringiensis δ-endotoxin synthesis gene, was tested for its efficacy to synthesize δ-endotoxin, in a complex medium containing sucrose and yeast extract. Also, the recombinant E. coli strain was tested for its efficacy against the 2nd instars of Spodoptera littoralis. The recombinant strain of E. coli showed a good activity against the 2nd instars of S. littoralis, the mortality was 70 % after 7 days at room temperature. A high cell biomass (8.8gL-1) and δ-endotoxin concentration (6.8 mg L-1), were obtained by the shake flask culture (100 ml medium/250 ml flask, at 200 rpm), of the recombinant E. coli in modified MR medium containing sucrose (20g/L), as carbon source and yeast extract as nitrogen source, in the presence of CaCO3, K2HPO4, MgSO4, FeSO4 and ZnSO4 as mineral salts. The best pH values for cell biomass production and endotoxin production were 7.0 and 7.5, respectively. The corresponding figures for the best temperature were 37oC and 30oC, respectively. The use of some byproducts such as black-strap molasses, corn-steep liquor and cheese whey, as an alternative for carbon and nitrogen sources of medium, were found to enhance the cell growth but showed no effect on endotoxin production

Development of the conditional moment closure method for modelling turbulent combustion

Abstract Objective: The purpose of this study was to evaluate the effects of low-level laser irradiation (LLLI) on the in vitro growth characteristics and in vivo pathogenicity of Candida albicans in a murine model in the absence of a photosensitizer. Background data: C. albicans is an opportunistic commensal organism that causes a wide variety of diseases in human beings, ranging from superficial infections to life-threatening invasive candidiasis. The incidence of C. albicans infection is increasing, because of the greater frequency of acquired immunodeficiency conditions. A high recurrence rate has been reported for vulvovaginal and oral candidiasis, despite the best available treatments. Therefore, the search for new treatment modalities seems quite rational. Methods: Candida culture plates were exposed to common clinical energies of LLLI: 3, 5, 10, and 20 J at 685 nm (BTL Laser 5000, Medicinos Projektai, Czech Republic, Prague, max power output 50 mW) and 3, 5, 10, 30, and 50 J at 830 nm (BTL Laser 5000, Medicinos Projektai, Czech Republic, Prague, max power output 400 mW). Results: Following LLLI with energies >10 J at both 685 and 830 nm wavelengths, statistically significant effects were observed in vitro on the turbidimetric growth kinetics of C. albicans and in vivo on the survival rate of infected mice (p value </=0.05). Therefore, this energy could be considered a threshold for clinical investigation. Conclusions: Translating our data into the clinical setting, it can be proposed that a direct laser-based approach without using a photosensitizing dye can significantly reduce the pathogenicity of Candida albicans. It can also be concluded that laser light at specific wavelengths could be a possible promising novel treatment for superficial and mucocutaneous C. albicans infections

Preparation and Evaluation of a New Lipopolysaccharide-based Conjugate as a Vaccine Candidate for Brucellosis

Objectives: Development of an efficacious vaccine against brucellosis has been a challenge for scientists for many years. At present, there is no licensed vaccine against human brucellosis. To overcome this problem, currently, antigenic determinants of Brucella cell wall such as Lipopolysaccharide (LPS) are considered as potential candidates to develop subunit vaccines. Methods: In this study, Brucella abortus LPS was used for conjugation to Neisseria meningitidis serogroup B outer membrane vesicle (OMV) as carrier protein using carbodiimide and adipic acid-mediated coupling and linking, respectively. Groups of eight BALB/c mice were injected subcutaneously with 10μg LPS alone, combined LPS+OMV and conjugated LPS-OMV on 0 days, 14 days, 28 days and 42 days. Anti-LPS IgG was measured in serum. Results: The yield of LPS to OMV in LPS-OMV conjugate was 46.55, on the basis of carbohydrate content. The ratio for LPS to OMV was 4.07. The LPS-OMV conjugate was the most immunogenic compound that stimulated following the first injection with increased IgG titer of ~5-fold and ~1.3-fold higher than that produced against LPS and LPS in noncovalent complex to OMV (LPS+OMV), respectively. The highest anti-LPS IgG titer was detected 2 weeks after the third injection (Day 42) of LPS-OMV conjugate. The conjugated compound elicited higher titers of IgG than LPS+OMV, that showed a 100-120-fold rise of anti-LPS IgG in mice. Conclusion: These results indicate that our conjugated LPS-OMV can be used as a brucellosis vaccine, but further investigation is required. © 2014