4,287 research outputs found

    Coupled electromagnetic and thermal analysis of electric machines

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    This paper deals with the design process of electric machines, proposing a design flowchart which couples the electromagnetic and thermal models of the machine, assisted by finite element techniques. The optimization of an electrical machine, in terms of the energy efficiency and cost reduction requirements, benefits from the coupling design of the electromagnetic and thermal models. It allows the maximization of the current density and, consequently, the torque/power density within thermal limits of the active materials. The proposed coupled electromagneticthermal analysis is demonstrated using a single-phase transformer of 1 kVA. Finite element analysis is carried out via ANSYS Workbench, using Maxwell 3D for the electromagnetic design, with resistive and iron losses directly coupled to a steady-state thermal simulation, in order to determine the temperature rise which, in turn, returns to electromagnetic model for material properties update.This work has been supported by FCT – Fundação para a Ciência e Tecnologia within the Project Scope: UIDB/05757/2020.info:eu-repo/semantics/publishedVersio

    Treatment of atherosclerotic renovascular hypertension: review of observational studies and a meta-analysis of randomized clinical trials.

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    open9Atherosclerotic renal artery stenosis can cause ischaemic nephropathy and arterial hypertension. We herein review the observational and randomized clinical trials (RCTs) comparing medical and endovascular treatment for control of hypertension and renal function preservation. Using the Population Intervention Comparison Outcome (PICO) strategy, we identified the relevant studies and performed a novel meta-analysis of all RCTs to determine the efficacy and safety of endovascular treatment when compared with medical therapy. The following outcomes were examined: baseline follow-up difference in mean systolic and diastolic blood pressure (BP), serum creatinine, number of drugs at follow-up, incident events (heart failure, stroke, and worsening renal function), mortality, cumulative relative risk of heart failure, stroke, and worsening renal function. Seven studies comprising a total of 2155 patients (1741 available at follow-up) were considered, including the recently reported CORAL Study. Compared with baseline, diastolic BP fell more at follow-up in patients in the endovascular than in the medical treatment arm (standard difference in means -0.21, 95% confidence interval (CI): -0.342 to -0.078, P = 0.002) despite a greater reduction in the mean number of antihypertensive drugs (standard difference in means -0.201, 95% CI: -0.302 to -0.1, P < 0.001). At variance, follow-up changes (from baseline) of systolic BP, serum creatinine, and incident cardiovascular event rates did not differ between treatment arms. Thus, patients with atherosclerotic renal artery stenosis receiving endovascular treatment required less anti-antihypertensive drugs at follow-up than those medically treated. Notwithstanding this, they evidenced a better control of diastolic BP.openopenCaielli P;Frigo AC;Pengo MF;Rossitto G;Maiolino G;Seccia TM;Calò LA;Miotto D;Rossi GPCaielli, P; Frigo, ANNA CHIARA; Pengo, Mf; Rossitto, G; Maiolino, G; Seccia, TERESA MARIA; Calò, La; Miotto, Diego; Rossi, Gianpaol

    Mycobacterium tuberculosis drug-resistance testing: challenges, recent developments and perspectives

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    Drug-resistance testing, or antimicrobial susceptibility testing (AST), is mandatory for Mycobacterium tuberculosis in cases of failure on standard therapy. We reviewed the different methods and techniques of phenotypic and genotypic approaches. Although multiresistant and extensively drug-resistant (MDR/XDR) tuberculosis is present worldwide, AST for M. tuberculosis (AST-MTB) is still mainly performed according to the resources available rather than the drug-resistance rates. Phenotypic methods, i.e. culture-based AST, are commonly used in high-income countries to confirm susceptibility of new cases of tuberculosis. They are also used to detect resistance in tuberculosis cases with risk factors, in combination with genotypic tests. In low-income countries, genotypic methods screening hot-spot mutations known to confer resistance were found to be easier to perform because they avoid the culture and biosafety constraint. Given that genotypic tests can rapidly detect the prominent mechanisms of resistance, such as the rpoB mutation for rifampicin resistance, we are facing new challenges with the observation of false-resistance (mutations not conferring resistance) and false-susceptibility (mutations different from the common mechanism) results. Phenotypic and genotypic approaches are therefore complementary for obtaining a high sensitivity and specificity for detecting drug resistances and susceptibilities to accurately predict MDR/XDR cure and to gather relevant data for resistance surveillance. Although AST-MTB was established in the 1960s, there is no consensus reference method for MIC determination against which the numerous AST-MTB techniques can be compared. This information is necessary for assessing in vitro activity and setting breakpoints for future anti-tuberculosis agents

    Desenvolvimento de uma versão adaptada do Boston Naming Test para a língua portuguesa

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    OBJECTIVE: To present the development of an adapted version of the Boston Naming Test for Portuguese speakers, and to investigate the effects of age, education and gender on both the original and the adapted Boston Naming Test in respect of Brazilian Portuguese speakers. METHOD: Eighty items, including the 60 original ones and 20 adapted items were administered to 739 healthy Brazilian subjects aged between 6 and 77 years who received 0 to 17 years of education. RESULTS: The coefficients of the General Linear Model estimation suggested that both age and education were statistically significant to predict total scores. In addition, score variances, justified by such predictors, were 41.20% in the original Boston Naming Test against 25.84% in the adapted Boston Naming Test. These results suggest that the scores from the original BNT are more dependent on age and education than those from the adapted Boston Naming Test. CONCLUSION: These findings demonstrated the suitability of the adapted Boston Naming Test version for the Brazilian population and described provisional norms for the original and adapted Boston Naming Test for Portuguese speakers.OBJETIVO: Apresentar o desenvolvimento de uma versão adaptada do Boston Naming Test para a língua portuguesa e investigar os efeitos da idade, escolaridade e gênero nas versões original e adaptada do Boston Naming Test. MÉTODO: 80 itens foram administrados incluindo os 60 originais e 20 itens adaptados em 739 brasileiros saudáveis com idades entre 6 e 77 anos e escolaridade entre 0 e 17 anos. RESULTADOS: Os coeficientes de estimação do Modelo Linear Geral sugeriram que a idade e escolaridade eram preditores significativos do resultado total. Além disto, as variâncias dos resultados explicadas por estes preditores no Boston Naming Test original era de 41,20%, enquanto que no adaptado era de 25,84%. Estes achados sugerem que os resultados do Boston Naming Test original são mais dependentes de idade e escolaridade do que os do adaptado. CONCLUSÃO: Estes achados demonstram a adequação do Boston Naming Test adaptado para a população brasileira e descrevem normas provisionais da versão original e adaptada do Boston Naming Test para a língua portuguesa

    Treatment of Hepatitis C virus genotype 3 infection with direct-acting antiviral agents

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    Hepatitis C virus (HCV) genotype 3 is responsible for 30.1% of chronic hepatitis C infection cases worldwide. In the era of directacting antivirals, these patients have become one of the most challenging to treat, due to fewer effective drug options, higher risk of developing cirrhosis and hepatocellular carcinoma and lower sustained virological response (SVR) rates. Currently there are 4 recommended drugs for the treatment of HCV genotype 3: pegylated interferon (PegIFN), sofosbuvir (SOF), daclatasvir (DCV) and ribavirin (RBV). Treatment with PegIFN, SOF and RBV for 12 weeks has an overall SVR rate of 83-100%, without significant differences among cirrhotic and non-cirrhotic patients. However, this therapeutic regimen has several contra-indications and can cause significant adverse events, which can reduce adherence and impair SVR rates. SOF plus RBV for 24 weeks is another treatment option, with SVR rates of 82-96% among patients without cirrhosis and 62-92% among those with cirrhosis. Finally, SOF plus DCV provides 94-97% SVR rates in non-cirrhotic patients, but 59-69% in those with cirrhosis. The addition of RBV to the regimen of SOF plus DCV increases the SVR rates in cirrhotic patients above 80%, and extending treatment to 24 weeks raises SVR to 90%. The ideal duration of therapy is still under investigation. For cirrhotic patients, the optimal duration, or even the best regimen, is still uncertain. Further studies are necessary to clarify the best regimen to treat HCV genotype 3 infection491

    Determinazione di un indice sintetico per la valutazione dell’effetto di laminazione

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    Working-Paper 2006-2, Dipartimento di Idraulica, Trasporti ed Infrastrutture Civili, Politecnico di Torino, 200

    Adsorption of C2H2-C2O3 on Si(001)

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    The adsorption of maleic anhydride on the Si(001) surface was investigated using the first-principles pseudopotential formalism. Our results indicate that C2H2-C2O3 adsorbs through a [2+2] cycloaddition of the C-C bond to the dangling bonds of Si-Si dimers, as observed for other small hydrocarbons. According to our calculations, the adsorption of a second maleic anhydride molecule will preferentially occur on first-neighbours Si-Si dimer sites in either the dimer chain our dimer row, i.e. considering a (4×2) reconstruction, C2H2-C2O3 can either form a linear chain or a zig-zag chain, depending on the growth conditions. Although both structures are found to be stable from the energetic point of view, only our STM theoretical images for the linear chain are comparable to available experimental data

    The health impact of hazardous waste landfills and illegal dumps contaminated sites: An epidemiological study at ecological level in Italian Region

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    Background and aim: The implementation of idoneous management of hazardous waste, in contrast to illegal practices, is one of the environment and health priorities of the WHO. The aim of the present study, based on a collaborative agreement between the Italian National Health Institute and a Prosecution Office located in Naples North, was to evaluate the health effects of illegal landfills and burning of urban and hazardous waste in the territory of the Prosecution Office. Methods: The municipalities included in the study territory were investigated with respect to the regional population. Regression analyses were performed in the study area between four classes of an environmental municipal indicator of waste risk (MRI) previously defined, computing the relative risks (RRs) in 2–4 MRI classes, with respect to the first MRI class (the least impacted). The prevalence of reproductive outcomes and cause-specific mortality and hospitalization were analyzed in the general population and in the 0–19-year-old population using SAS software. Results: An increase of mortality and hospitalization risk in both the genders of the whole area, with respect to regional population, were found for overall all cancer cases, cancer of the stomach, the liver, the lung and the kidney, and ischemic heart diseases. An increase of mortality for leukemias in the 0-19-year-old population and in hospitalization risk for certain conditions originating in the perinatal period were observed. Correlation between MRI and the risk of mortality from breast tumors in women (MRI class 2: RR = 1.06; MRI class 3: RR = 1.15; MRI class 4: RR = 1.11) and between MRI and the risk of hospitalization from testis tumors (MRI class 2: RR = 1.25; MRI class 3: RR = 1.31; MRI class 4: RR = 1.32) were found. The hospitalization risk from breast tumors and asthma exceeded significantly in both genders of three and four MRI classes. Among the 0-19-year-old population, correlation between MRI and hospitalization from leukemias (MRI class 2: RR = 1.48; MRI class 3: RR = 1.60; MRI class 4: RR = 1.41) and between MRI and the prevalence of preterm birth (MRI class 2: RR = 1.17; MRI class 3: RR = 1.08; MRI class 4: RR = 1.25) were found. Conclusion: A correlation between health outcomes and the environmental pressure by uncontrolled waste sites was found. Notwithstanding the limitation of the study, the results promote implementing the actions of environmental remediation and the prosecution of illegal practices

    Predictors Of Early Treatment Discontinuation And Severe Anemia In A Brazilian Cohort Of Hepatitis C Patients Treated With First-generation Protease Inhibitors

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    The aim of this study was to determine risk factors for adverse events (AE)-related treatment discontinuation and severe anemia among patients with chronic hepatitis C virus (HCV) genotype 1 infection, treated with first-generation protease inhibitor (PI)-based therapy. We included all patients who initiated treatment with PI-based therapy at a Brazilian university hospital between November 2013 and December 2014. We prospectively collected data from medical records using standardized questionnaires and used Epi Info 6.0 for analysis. Severe anemia was defined as hemoglobin <= 8.5 mg/dL. We included 203 patients: 132 treated with telaprevir (TVR) and 71 treated with boceprevir (BOC). AE-related treatment discontinuation rate was 19.2% and anemia was the main reason (38.5%). Risk factors for treatment discontinuation were higher comorbidity index (OR=1.85, CI=1.05-3.25) for BOC, and higher bilirubin count (OR=1.02, CI=1.01-1.04) and lower BMI (OR=0.98, CI=0.96-0.99) for TVR. Severe anemia occurred in 35 (17.2%) patients. Risk factors for this outcome were lower estimated glomerular filtration rate (eGFR; OR=0.95, CI=0.91-0.98) for patients treated with TVR, and higher comorbidity index (OR=2.21, CI=1.04-4.67) and ribavirin dosage (OR=0.84, CI=0.72-0.99) for those treated with BOC. Fifty-five (57.3%) patients treated with TVR and 15 (27.3%) patients treated with BOC achieved sustained virological response (SVR). Among patients who received TVR and interrupted treatment due to AE (n=19), only 26.3% (n=5) achieved SVR (P=0.003). Higher number of comorbidities, lower eGFR and advanced liver disease are associated with severe anemia and early treatment cessation, which may compromise SVR achievement.49
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