Harmonic current sideband indicators (HCSBIs) for broken bar detection and diagnostics in cage induction motors

Induction motor bar breakages have been increasingly studied in the last decades because of economic interests in developing techniques that permit on-line, non-invasive, early detection of motor faults in power plants. This work is specifically focused on broken bar detection and fault severity assessment in three phase power cage motors fed by non-sinusoidal voltage sources. In this work some new fault indicators for rotor bar breakages detection in squirrel cage induction motors are proposed, mathematically developed and experimentally proved. They are based on the sidebands of phase current upper harmonics, and they are well suited especially for converter-fed induction motors. The ratios I(7-2s)f/I5f and I(5+2s)f/I7f , I(13-2s)f/I11f and I(11+2s)f/I13f are examples of such new indicators, and they are not dependent on load torque and drive inertia, as classical indicators do. Their frequency-dependence has been also examined both theoretically and experimentally, and it was found less remarkable with respect to other indicators. Moreover, their values increase linearly with the quantity of consecutive broken bars, almost for not too much advanced faults; on 4-poles motors they were found quietly like the per-unit number of broken bars (ratio on total bar number). An original formulation is presented for motor mathematical modeling, based on the Generalized Symmetrical Components Theory, for sidebands amplitude computation. A complete motor model (involving all the elementary machine electrical circuits, as stator belts and rotor mesh loops) has been used for computer simulations; the same model was then transformed by using some complex Fortescue’s matrices to obtain a steady-state linear solution, solvable for stator and rotor currents, in healthy and faulty conditions. By exploiting the model, the formal definition of a set of new broken bar indicators was finally obtained. Machine simulations carried out by running the complete numerical model confirmed the accuracy of the model, and the theoretical previsions. Experimental work was performed by using a square-wave inverter-fed motor with an appositely prepared cage, for easy testing with increasing number of broken bars and without motor dismounting. Moreover, extensive experimentation was carried out on three industrial motors with different power and poles number, with increasing load, frequency and fault gravity for methodology validation. Finally, the ideas exposed in this work led to a patent application, owned by the University of Rome “Sapienza”

Diagnosis of Eccentric Rotor in Synchronous Machines by Analysis of Split-Phase Currents—Part I: Theoretical Analysis

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Avaluació de la capacitat de salt i estat ponderal d’estudiants de dansa clàssica de l’escola del Teatro Colón de Buenos Aires

  Introducció: L’objectiu d’aquest estudi fou avaluar la capacitat de salt, el pes corporal i la talla d’estudiants de l’escola de dansa clàssica del Teatro Colón de Buenos Aires.Material i mètodes: Cinquanta estudiants femenines (10 a 21 anys) i 16 masculins (10 a 26 anys). Variables: estatura (m), pes (kg), índex de massa corporal, alçada (cm) del salt sense contramoviment (SJ), del salt amb contramoviment (CMJ), índex d’elasticitat (IE) (%).Resultats: Pes baix el 38% de les dones i el 6,3% dels homes. A les dones se’ls aplicà el test t per a grups independents segons categories d’edat, entre categories d’estat nutricional, per als salts SJ, CMJ, IE, sense diferències significatives. Es realitzà un ANOVA d’una via entre categories d’edat per a l’SJ, CMJ, IE, sense diferències significatives per a l’SJ (F = 0,8; p = 0,46), CMJ (F = 0,28; p = 0,76), IE (F = 0,61; p = 0,55). En els homes la prova ANOVA d’una via entre categories d’edat mostrà significació en l’SJ (F = 9,97; p = 0,002) i el CMJ (F = 17,58; p = 0,00). Hi hagué diferències entre la categoria 1 amb la 2 i la 3, que tendiren a agrupar-se (test post hoc de Scheffé, p < 0,05). IE: test de Kruskal-Wallis, sense diferències significatives entre categories d’edat (χ2 = 2,17; p = 0,34). Qualitat del salt: 68% dels homes i 42% de les dones assoliren un IE ≥ 6%, cosa que indica bona relació CMJ/SJ.Conclusions: Es suggereixen controls de salut atès l’elevat nombre de ballarines de baix pes. Pel que fa al salt, el grup de dones en podria millorar la capacitat

Osteonecrosis Múltiple inducida por glucocorticoides

La osteonecrosis múltiple es una entidad poco frecuente que se define por el compromiso de al menos tres regiones diferentes. Es indispensable el abordaje multidisciplinario de los pacientes que la padecen tanto para el diagnóstico como el tratamiento oportuno. Presentamos el caso clínico de un paciente joven que presenta una osteonecrosis múltiple con compromiso de ambas caderas, hombros, rodillas, codo derecho y cuello de pie izquierdo. El principal factor de riesgo presente en nuestro caso es el consumo de glucocorticoides

Trends in Fault Diagnosis for Electrical Machines

[EN] The fault diagnosis of rotating electrical machines has received an intense amount of research interest during the last 30 years. Reducing maintenance costs and preventing unscheduled downtimes, which result in losses of production and financial incomes, are the priorities of electrical drives manufacturers and operators. In fact, both correct diagnosis and early detection of incipient faults lead to fast unscheduled maintenance and short downtime for the process under consideration. They also prevent the harmful and sometimes devastating consequences of faults and failures. This topic has become far more attractive and critical as the population of electric machines has greatly increased in recent years. The total number of operating electrical machines in the world was around 16.1 billion in 2011, with a growth rate of about 50% in the last five years [1].Henao, H.; Capolino, G.; Fernández-Cabanas, M.; Filippetti, F.; Bruzzese, C.; Strangas, E.; Pusca, R.... (2014). Trends in Fault Diagnosis for Electrical Machines. IEEE Industrial Electronics Magazine. 8(2):31-42. doi:10.1109/MIE.2013.2287651S31428

Clinical importance and impact on the households of oseltamivir-resistant seasonal A/H1N1 influenza virus in healthy children in Italy

A resistance of A/H1N1 influenza viruses to oseltamivir has recently emerged in a number of countries. However, the clinical and socioeconomic importance of this resistance has not been precisely defined. As children have the highest incidence of influenza infection and are at high risk of severe disease, the aim of this study was to evaluate the clinical importance and the impact on the households of oseltamivir-resistant seasonal A/H1N1 influenza virus in an otherwise healthy pediatric population. A total of 4,726 healthy children younger than 15 years with influenza-like illness were tested for influenza viruses by real-time polymerase chain reaction in the winters of 2007-2008 and 2008-2009 in Italy. The influenza A virus-positive samples underwent neuraminidase gene analysis using pyrosequencing to identify mutations H275Y and N294 S in A/H1N1, and E119V, R292K, and N294 S in A/H3N2. Among the A/H1N1 subtypes, the H275Y mutation was found in 2/126 samples taken in 2007-2008 (1.6%) and in all 17 samples (100%; p < 0.0001) taken in 2008-2009. No other mutation was identified in any of the A/H1N1 or A/H3N2 influenza viruses. No significant differences were found in terms of clinical importance or impact on the households between the children with oseltamivir-resistant seasonal A/H1N1 influenza virus and those with the wild-type. The spread of H275Y-mutated A/H1N1 seasonal influenza virus is a common phenomenon and the clinical importance and impact on the households of the mutated virus is similar to that of the wild-type in an otherwise healthy pediatric population

Demographic, tumor and clinical features of clinical trials versus clinical practice patients with HER2-positive early breast cancer: results of a prospective study

Several randomized clinical trials (RCTs) have demonstrated the efficacy of trastuzumab-based adjuvant therapy in HER2-positive breast cancer (BC). However, RCT patients may not invariably be representative of patients routinely seen in clinical practice (CP). To address this issue, we compared the clinical and tumor features of RCT and CP patients with HER2-positive BC

Long-term treatment with sulfhydryl angiotensin-converting enzyme inhibition reduces carotid intima-media thickening and improves the nitric oxide/oxidative stress pathways in newly diagnosed patients with mild to moderate primary hypertension.

Aim. Sulfhydryl angiotensin-converting enzyme (ACE) inhibitors exert antiatherosclerotic effects in preclinical models and antioxidant effects in patients. However, whether ACE inhibitors have any clinically significant antiatherogenic effects remains still debated. Objectives. In mildly hypertensive patients, we evaluated the effect of the sulfhydryl ACE inhibitor zofenopril in comparison with the carboxylic ACE inhibitor enalapril on carotid atherosclerosis (intima-media thickness [IMT] and vascular lumen diameter) and systemic oxidative stress (nitrite/nitrate, asymmetrical dimethyl-L-arginine, and isoprostanes). Material and methods. In 2001, we started a small prospective randomized clinical trial on 48 newly diagnosed mildly hypertensive patients with no additional risk factors for atherosclerosis (eg, hyperlipidemia, smoke habit, familiar history of atherosclerosisrelated diseases or diabetes). Patients were randomly assigned either to the enalapril (20 mg/d, n = 24) or the zofenopril group (30 mg/d, n = 24); the planned duration of the trial was 5 years. Carotid IMT and vascular lumen diameter were determined by ultrasonography for all patients at baseline and at 1, 3, and 5 years. Furthermore, nitrite/nitrate, asymmetrical dimethyl-L-arginine, and isoprostane levels were measured. Results. In our conditions, IMT of the right and left common carotid arteries was similar at baseline in both groups (P = NS). Intima-media thickness measurements until 5 years revealed a significant reduction in the zofenopril group but not in the enalapril group (P b .05 vs enalapril-treated group). This effect was coupled with a favorable nitric oxide/oxidative stress profile in the zofenopril group. Conclusion. Long-term treatment with the sulfhydryl ACE inhibitor zofenopril besides its blood pressure–lowering effects may slow the progression of IMT of the carotid artery in newly diagnosed mildly hypertensive patients. (Am Heart J 2008;156:1154.e1-1154.e8.

Clinical and socioeconomic impact of different types and subtypes of seasonal influenza viruses in children during influenza seasons 2007/2008 and 2008/2009

<p>Abstract</p> <p>Background</p> <p>There are few and debated data regarding possible differences in the clinical presentations of influenza A/H1N1, A/H3N2 and B viruses in children. This study evaluates the clinical presentation and socio-economic impact of laboratory-confirmed influenza A/H1N1, A/H3N2 or B infection in children attending an Emergency Room because of influenza-like illness.</p> <p>Methods</p> <p>Among the 4,726 children involved, 662 had influenza A (143 A/H1N1 and 519 A/H3N2) and 239 influenza B infection detected by means of real-time polymerase chain reaction. Upon enrolment, systematic recordings were made of the patients' demographic characteristics and medical history using standardised written questionnaires. The medical history of the children was re-evaluated 5-7 days after enrolment and until the resolution of their illness by means of interviews and a clinical examination by trained investigators using standardised questionnaires. During this evaluation, information was also obtained regarding illnesses and related morbidity among households.</p> <p>Results</p> <p>Children infected with influenza A/H1N1 were significantly younger (mean age, 2.3 yrs) than children infected with influenza A/H3N2 (mean age, 4.7 yrs; p < 0.05)) or with influenza B (mean age, 5.2 yrs; p < 0.05). Adjusted for age and sex, children with influenza A/H3N2 in comparison with those infected by either A/H1N1 or with B influenza virus were more frequently affected by fever (p < 0.05) and lower respiratory tract involvement (p < 0.05), showed a worse clinical outcome (p < 0.05), required greater drug use (p < 0.05), and suffered a worse socio-economic impact (p < 0.05). Adjusted for age and sex, children with influenza B in comparison with those infected by A/H1N1 influenza virus had significantly higher hospitalization rates (p < 0.05), the households with a disease similar to that of the infected child (p < 0.05) and the need for additional household medical visits (p < 0.05).</p> <p>Conclusions</p> <p>Disease due to influenza A/H3N2 viral subtype is significantly more severe than that due to influenza A/H1N1 subtype and influenza B virus, which indicates that the characteristics of the different viral types and subtypes should be adequately considered by health authorities when planning preventive and therapeutic measures.</p

Elotuzumab plus pomalidomide and dexamethasone in relapsed/refractory multiple myeloma: a multicenter, retrospective real-world experience with 200 cases outside of controlled clinical trials

In the ELOQUENT-3 trial, the combination of elotuzumab, pomalidomide and dexamethasone (EloPd) proved a superior clinical benefit over Pd with a manageable toxicity profile, leading to its approval in relapsed/refractory multiple myeloma (RRMM), who had received at least two prior therapies, including lenalidomide and a proteasome inhibitor (PI). We report here a real-world experience of 200 RRMMs treated with EloPd in 35 Italian centers outside of clinical trials. In our dataset, the median number of prior lines of therapy was 2, with 51% of cases undergoing autologous stem cell transplant (ASCT) and 73% exposed to daratumumab. After a median follow-up of 9 months, 126 patients stopped EloPd, most of them (88.9%) because of disease progression. The overall response rate (ORR) was 55.4%, in line with the pivotal trial results. Regarding adverse events, our cohort experienced a toxicity profile similar to the ELOQUENT-3 trial, with no significant differences between younger (&lt;70 years) and older patients. The median progression-free survival (PFS) was 7 months, shorter than that observed in the ELOQUENT-3, probably due to the different clinical characteristics of the two cohorts. Interestingly, the ISS stage III (HR:2.55) was associated with worse PFS. Finally, our series's median overall survival (OS) was shorter than that observed in the ELOQUENT-3 trial (17.5 versus 29.8 months). In conclusion, our real-world study confirms EloPd as a safe and possible therapeutic choice for RRMM who received at least two prior therapies, including lenalidomide and a PI