13 research outputs found

    Design of outer?rotor permanent?magnet?assisted synchronous reluctance motor for electric vehicles

    No full text
    Today’s automotive industry has focused its studies on electric vehicles (EVs) or hybrid electric vehicles (HEVs) rather than gasoline?powered vehicles. For this reason, more investment has been made in electric motors with high efficiency, high torque density, and high?power factor to be used in both EVs and HEVs. In this study, an outer?rotor permanent?magnet?assisted synchronous reluctance motor (PMaSynRM) with a new rotor topology was designed for use in an EV. The design has a transversally laminated anisotropic (TLA) rotor structure. In addition, neodymiumiron?boron (NdFeB) magnets were used in rotor topology. The stator slots were designed as distributed windings, so torque ripples are minimized. At the same time, the maximum electromagnetic torque was achieved. The analysis of the designed motor was carried out using the finite element method (FEM). Optimal values of motor parameters were obtained by improving the rotor geometry of the three?phase PMaSynRM in order to obtain maximum torque and minimum torque ripple in the design. The motor is in a 48/8 slot/pole combination, a speed of 750 rpm and a power of 1 kW. The simulation results showed that the design achieved maximum torque and minimum torque ripple. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

    25-Gauge transconjunctival sutureless pars plana vitrectomy

    No full text
    PURPOSE. To evaluate the effectiveness, feasibility, and safety of the transconjunctival sutureless vitrectomy (TSV) system for a variety of vitreoretinal diseases. METHODS. In this retrospective study, the authors evaluated 71 eyes of 63 patients who underwent pars plana vitrectomy (PPV) with the 25-gauge TSV system. The indications for surgical intervention were diabetic vitreous hemorrhage (29 eyes), diabetic macular edema (14 eyes), macular epiretinal membrane (13 eyes), endophthalmitis (5 eyes), vitreous opacities secondary to Behçet's disease (4 eyes), vitreous hemorrhage secondary to branch retinal vein occlusion (4 eyes), and vitreous hemorrhage secondary to age-related macular degeneration (2 eyes). Epiretinal membrane and internal limiting membrane removal, endolaser photocoagulation, and air-fluid exchange were performed when required. RESULTS. Mean follow-up was 3.6 months (range 1-8 months). Mean overall visual acuity (VA) was counting fingers (range light perception to 0.4) preoperatively and 0.2 (range 0.1 to 0.8) postoperatively (p=0.000). Statistically significant VA improvement was observed in eyes with vitreous hemorrhage, diabetic macular edema, and macular epiretinal membrane. VA improved postoperatively in all eyes with endophthalmitis and vitreous opacities secondary to Behçet's disease. The surgery was completed without conjunctival and scleral suturing in all eyes. Mean intraocular pressure (IOP) was 17.2 mmHg (range 10-26 mmHg) preoperatively, 12.4 mmHg (range 6-24 mmHg) on the first postoperative day, 16.6 mmHg (range 10-33 mmHg) at 1 week, and 15.4 mmHg (range 10-20 mmHg) at 1 month postoperatively. On the first postoperative day, IOP was below 10 mmHg (between 6 and 9 mmHg) in 12 eyes (16.9%). In these eyes, IOP was normalized within 1 week without affecting the visual outcome. Five eyes (7%) had transient increase of IOP controlled by topical antiglaucomatous medications. Vitreous washout using 25-gauge TSV system was performed in two eyes, in which vitreous hemorrhage recurred. CONCLUSIONS. The TSV system was observed to be feasible, effective, and safe for a variety of vitreoretinal diseases. This minimally invasive and completely sutureless (transconjunctival) technique appears to decrease the convalescence period, operating time, and post-operative inflammatory response, and improve patient comfort. © Wichtig Editore, 2006

    Asthma phenotypes in Turkey: a multicenter cross-sectional study in adult asthmatics; PHENOTURK study

    No full text
    Background and Aims: To evaluate asthma phenotypes in patients with asthma from different regions of Turkey. Methods: A total of 1400 adult asthmatic patients (mean (SD) age: 44.0 (13.9) years, 75% females) from 14 centers across Turkey were included in this study and a standard questionnaire was applied between the time period of February 2011–January 2012. Results: The disease onset ≥ 40 years of age was higher percentage in obese vs. normal/overweight patients and nonallergic vs. allergic patients (P < 0.01). The percentage of patients who had FEV1 values over 80% was higher in allergic than nonallergic and normal/overweight than obese patients (P < 0.01). Uncontrolled asthmatics have more severe disease (P < 0.01). There were more frequent hospital admissions in nonallergic and uncontrolled asthmatics (P < 0.01). Chronic rhino-sinusitis was the leading comorbid disorder in normal/overweight and allergic asthma, while gastroesophageal reflux disorder was more frequent in nonallergic and uncontrolled asthma (P < 0.01). Asthma control rate was the highest (39.0%) in patients from Marmara region among all geographical regions (P < 0.05). Conclusion: In conclusion, our findings revealed existence of clinical/trigger related phenotypes based on BMI, allergic status, control level and geographical region with more frequent respiratory dysfunction and/or adverse health outcomes in uncontrolled, obese and nonallergic phenotypes. © 2015 John Wiley & Sons Lt

    Inappropriate Antimicrobial Use In Turkish Pediatric Hospitals: A Multicenter Point Prevalence Survey

    Get PDF
    Objectives: Although well-defined principles of rational antimicrobial use are available, inappropriate prescribing patterns are reported worldwide. Accurate information on the usage of antimicrobials, including factors associated with and influencing their use, is valuable for improving the quality of prescription practices. Methods: In this cross-sectional point prevalence survey, data on patients hospitalized in 12 different children's hospitals were collected on a single day. Appropriateness of prescription was compared between the types of antimicrobials prescribed, indications, wards, and presence of/consultation with an infectious disease physician (IDP). Results: A total 711 of 1302 (54.6%) patients evaluated were receiving one or more antimicrobial drugs. The antimicrobial prescription rate was highest in pediatric intensive care (75.7%) and lowest in the surgery wards (37.0%). Of the 711 patients receiving antimicrobials, 332 patients (46.7%) were found to be receiving at least one inappropriately prescribed drug. Inappropriate use was most frequent in surgery wards (80.2%), while it was less common in oncology wards (31.8%; p < 0.001). Respiratory tract infection was the most common indication for antimicrobial use (29.4%). Inappropriate use was more common in deep-seated infections (54.7%) and respiratory infections (56.5%). Fluoroquinolones were used inappropriately more than any other drugs (81.8%, p = 0.021). Consultation with an IDP appears to increase appropriate antimicrobial use (p = 0.008). Conclusions: Inappropriate antimicrobial use remains a common problem in Turkish pediatric hospitals. Consultation with an IDP and prescribing antimicrobial drugs according to microbiological test results could decrease the inappropriate use of antimicrobials. (C) 2009 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.WoSScopu
    corecore